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The decline of the performance of the human muscle with aging is out of discussion. The rate of decline can be very well drawn from the decline of the world records of the master athletes in various track and field disciplines. Actually all track and field events are power tests and the performance of the athletes can be transformed into dimensionless parameter proportional to the power developed in carrying out the events. These are astonishingly linear in behavior and points to 0 power at 110 years of age.1 For some of them (running events) the processing of the athletic results into power parameters associated with the age of the master athletes is simple; for the throwing events the dimensionless parameters are calculated with a two steps process; for the jumping events the processing is more problematic. In this area we are concentrating our present work because the jumping results (high jump) are not proportional to the power developed: this is proportional to the raising of the center of gravity of the athletes., There is something in our genome that dictates life expectancy and there is nothing that can be done to avoid this; indeed, there is not yet any record of a person who has cheated death. Our physical prowess can vacillate substantially in our lifetime according to our activity levels and nutritional status and we may fight aging, but we will inevitably lose.1 Premature or accelerated aging of muscle may occur as the result of many chronic diseases. One extreme case is provided by irreversible damage of the Conus and Cauda Equina, a spinal cord injury (SCI) sequela in which the human leg muscles may be completely and permanently disconnected from the nervous system with the almost complete disappearance of muscle fibers within 3-5 years from SCI.2 In cases of this extreme example of muscle degeneration, we have used 2D and 3D Muscle Color CT to gather data supporting the idea that electrical stimulation of denervated muscles can retain and even regain muscle.2-5 We show also that, if people are compliant, atrophy can be reversed, but if the home FES is discontinued, muscle degeneration occurs again.3-5 Here we would like to show that it is possible to extend the CM-CT approach to the cases of disuse muscle atrophy in incomplete denervation of muscle tissue, or just in aging.6 The tissue characterization process is based on using CT data and special software tools to segment and analyze the different tissues within a region of interest. In the process of assessing muscle quality in the lower limbs we discriminate the soft tissues dividing them in: subcutaneous fat, intramuscular fat, low density muscle, normal muscle and fibrous-dense connective tissues. The first step in the segmentation process is to establish a threshold, which discriminates the tissue of interest from the rest by grey value (CT number or Hounsfield value in CT modality). The second segmentation tool which typically follows thresholding is region growing. Region growing is an image segmentation approach in which neighboring pixels of the current region’s boundaries are examined and added to the region class if no edges are detected (or more generally some inclusion criteria is met). The Muscle Color Computed Tomography allows to: 1. Quantify the percent contents of the different soft tissues (muscle, fat and other connective tissues, either loose or fibrous) and 2. the volume of anatomically defined muscles (here, rectus femoris or tibialis anterior). The methods are used to measure in a patient (male, 53 years, ASIA 1, that had suffered with a trauma to the spinal cord 15 years before the MC-CT) the residual asymmetric innervation of the leg muscles and the effects on muscles of a 6-week rehabilitation regime that allowed the patient to perform short walks without crouches after years of supported walking and many hours a day of bed resting. Further, a young active male (35 years old) and a typical sedentary senior (male of 72-years) are also analyzed., Even in the absence of overt diseases, our physical capacity decays with age, fluctuating substantially in our lifetime according to activity levels and nutritional status. We may indeed fight aging by appropriate counter-measures, but we will inevitably lose. Further, we have presented evidence that the atrophy which accompanies aging is to some extent related to a background loss of innervation.1 Comparing muscle biopsies of sedentary seniors to those elderly with a lifelong high level of sport activity, we showed that these groups indeed have a different distribution of muscle fiber types and of their diameter. The senior sportsmen have many more slow fiber-type groupings than the sedentary people providing strong evidence of denervation-reinnervation of muscle fibers. It appears that activity maintains the motoneurons and the muscle fibers. Further, comparing muscle morphometry data of groups of sedentary (untrained) subjects to those obtained by the analyses of muscle biopsies from age-matched sedentary seniors at T0 there are no statistical significant differences, but after 9 weeks of training with either electrical stimulation (ES) or leg press (LP), interesting findings were observed.2,3 At T1, that is after 9 weeks of training in ES and LP groups, significant increases in the overall and fast type mean myofiber diameters were observed between the three groups (one way ANOVA p < 0.05). Further, the Bonferroni post-hoc test shows that these differences are statistically significant between the ES (p, Physical activity plays an important role in preventing chronic disease and muscle degeneration in adults and the elderly. Voluntary physical exercise is not always feasible and other therapies should be applied such as Functional Electrical Stimulation (FES) and/or Leg Press (LP) training.1-7 The key process of Calcium (Ca2+) storage uptake and release is essential in muscle adaptation. This study shows the effects of physical training (LP) and FES in situ in human Vastus Lateralis (VL) muscle. Through immunofluorescence analysis of muscle cryo-sections, a huge increment of NFAT positive nuclei, was found after both treatments (from 3% to 60%); moreover after both trainings an increment of P-CamkII was observed by western blotting analysis. These findings indicate that both trainings activate the CaM-dependent phosphatase signaling (known to be involved in muscle plasticity). Muscle total homogenates obtained from biopsies performed before and after completing a nine weeks FES treatment on a group of volunteers and Calsequestrin (CASQ), SERCA, Sarcalumenin, protein expression were determined by Western blot. After FES significant increase of SERCA2 and Sarcalumenin and decrease of CASQ1 were observed, while LP did not show any variations of proteins levels. Immunofluorescence analysis were also performed to localize in situ MHCII/SERCA2 co-expressing muscle fibers, an interesting tool to identify subpopulation of muscle fibers involved in muscle adaptation. The overall results indicate that the applied FES protocol, simulating a motoneuron slow-type firing pattern, potentiates Ca2+ uptake and storage in a peculiar class of skeletal muscle fibers, and further validates, at molecular level, the FES strategy.5-11, Damage to the recurrent laryngeal nerve (RLN) causes: 1. severe dyspnea because of bilateral paralyzed vocal cords and 2. An impaired voice in cases of unilateral damage of vocal cords because of reduced ability to bring the vocal fold on the damaged side to the midline. The same symptom is caused by reduced firing of the recurrent laryngeal nerve in aged related to disuse atrophy. Damage of the facial nerve leads to a loss of muscle tone and the soft tissues of the face. Voluntary motor movement is lost, and mimic muscles can no longer be moved. The inability to close the eyelid indirectly leads to vision disorders and the eye may dry out. Lack of mouth movement limits speaking and eating. Axonal collateral sprouting leads clinically to simultaneous movement of several target muscles (a condition called synkinesis) - involuntary lid closure while moving the mouth, e.g., when eating. Simultaneous movement of antagonist muscles leads to the autoparalytic syndrome: muscle forces cancel each other out and no movement is observed clinically despite innervation. Aging in the facial region typically means a loss of muscle tone, muscle volume and/or a loss or reduction of connective and fat tissue, e.g., below the eyes and/or at the cheek. As a result of the aging muscles, facial muscles and/or other facial tissues may diminish or atrophy. FES may be an effective method of providing training therapy to human subjects weakened or denervated muscles in order to strengthen a weakened voice or face. United States Patent Applications: Applicant: MED-EL Elektromedizinische Geraete GmbH, Innsbruck, AT, One of the main determinants of the overall size of neural implantable pulse generators is usually the size of the battery. Engineers are facing the challenge of designing devices that are small in volume whilst fulfilling their stimulation task as long as possible. Therefore efficient stimulation methods are crucial for their success. Wongsarnpigoon 1 pointed out three different types of stimulation efficiency. A “charge-efficient” stimulation could have the positive effect of reducing tissue damage. As the battery size is directly proportional to the maximal instantaneous power required – a “power-efficient” stimulation could reduce battery-size and therefore the overall size of an implant. An “energy- efficient” stimulation on the other hand, could be advantageous with regard to the battery lifetime. The aim of our project is to compare different rectangular waveforms according to their “energyefficiency”. 5 different rectangular waveforms (monophasic, biphasic, biphasic with interphase gap, asymmetric biphasic, asymmetric biphasic with interphase gap) that have shown potentially useful effects in other studies2-6 have been investigated. Bipolar stainless-steel loop electrodes were placed under the common peroneal nerve of rats under buprenorphine/isofluorane anaesthesia. The isometric force produced by the extensor-digitorum-longus muscle was measured using a load-cell. Our results did not support several of the claims made in the literature. Introducing an interphase-gap generally increased the stimulating currents necessary to reach a certain force-threshold. This was also the case for asymmetric waveforms. The standard symmetric biphasic pulse was the most energy-efficient, out of all tested waveforms. The differences between this experiment and other studies reflect different stimulation methods (mostly monopolar), stimulation patterns (mostly pulse trains) or stimulation sites (e.g. cochlear stimulation, epiretinal stimulation). But they emphasise that the specific relationship between the means of the injection of stimulation energy and the measured outcome need to be considered when efficiency or efficacy of stimulation is discussed. The results from this experiments were used to propose an algorithmic approach for finding stimulation parameters that yield a particular energy-minimum for a certain targeted force-level. These parameters provide a starting point for further parameter fitting sessions in clinical settings where electrical stimulation is applied., According to PubMed roughly 10% of the annually added publications are describing findings from the animal model. Half of these studies are done in mice and rats. It can be assumed that there is a need for implantable electrical stimulators which are flexible, reliable and small enough (~1cm3) that even mice can tolerate it and move freely. The MiniVStim 12A is a battery powered implant with an outer diameter of 15 mm and a volume of 1.2 cm3. It can be preprogramed according to the experimental protocol and controlled by resetting it with a magnet. It can deliver constant current monophasic pulses up to 2 mA and 1 ms pulse width (@ 1 kOhm). MiniVStim 12B has the same mechanical dimensions and electrical characteristics but can be fully programed via a wireless bidirectional data link. Both types of implants are already successfully used in studies. The latest generation of implants is the MiniVStim18B. It is slightly larger (22 mm outer diameter) than the 12B but offers the 8 fold battery life time. Moreover, it can deliver biphasic pulses and extends the stimulation parameter range up to 8 mA at a maximum output voltage of 10 V and pulse width of 5 ms (@ 1 kOhm) for monophasic and 2×5 ms for biphasic pulses. This extended parameter range gives the opportunity to perform long term studies on denervated muscles in small animals., Age related atrophy of the vocalis muscle and its adjacent structures affects the voice and may lead to presbyphonia, a condition affecting more and more people in aging western societies. So far therapy modalities comprised conservative speech therapy as well as phonosurgical approaches. Chronic electrical stimulation of the afferent nerve (recurrent laryngeal nerve, RLN) is a completely new therapeutic option that has not been tested before. 18 male Wistar rats were implanted with a unilateral nerve stimulator. One week after implantation stimulation protocol was initiated over eight weeks, twice daily. Changes were observed on the muscular level histologically (cross section area, number of muscle fibers etc.) as well as on the cellular level (immuno-histochemically and qPCR). All animals tolerated the stimulation procedures well and showed normal feeding. We could not identify differences in cross-section area, number of muscle fibers, or satellite cells. We identified a trend towards increased number of neuro-muscular junctions which failed slightly statistical significance. Our pilot study proved the technical feasibility of the implantation of a RLN pacemaker system in small rodents. We could not identify significant changes after eight weeks of stimulation in any parameter. We assume that this is due to the young age of the test animals. The next step will be to test these protocols in aged rats., Muscle atrophy is a hallmark of the ageing process and as such also affects the larynx, where it constitutes the major cause of presbyphonia, i.e. a considerable glottic gap with massive loss of air during phonation. Patients suffer from a highly hoarse voice and rapid vocal fatigue which leads to social withdrawal. Current treatment options are mainly conservative (e.g. speech therapy) and far from being satisfactory. Thus, novel approaches for promoting hypertrophy of aged laryngeal muscles are in demand. In this respect, electrical stimulation of motor neurons constitutes a promising strategy. Using aged sheep as an animal model, we recently completed a first efficacy study in which chronic electrical stimulation of laryngeal muscles was accomplished via a mini-electrode that targeted the right recurrent laryngeal nerve (RLN; unilateral stimulation). Based on preceding experiments, functional electrical stimulation (FES) implants were programmed to deliver a pattern able to evoke supramaximal muscle stimulation over a period of 29 days. Surgical and post-surgical interventions were well tolerated by all animals, FES implants remained functional throughout the whole study, and only relatively mild increases in the necessary threshold for muscular stimulation were recorded. At the end of the study, vocalis and posterior crico-arytenoid muscles were prepared to obtain samples for molecular and histological analyses. To quantify the expression levels of genes related to distinct muscle fiber types, a real-time PCR (RT-qPCR) analysis pipeline was newly established which will also be central to subsequent studies. First results of the analysis “at transcript level” will be discussed in the talk. Moreover, an outline of the planned further analyses will be presented., Stroke is a leading cause of adult disability and it is constantly increasing due to growing life expectancy and unhealthy lifestyles. Fibrinolysis is the main therapy for ischemic stroke, but it has a narrow therapeutic window. Neuroprotective treatment strategies that may have the potential to reduce damage or to enhance regenerative aspects are under investigations in many experimental models. The aim of this study was to evaluate the neuromodulation effect induced by vagus nerve stimulation (VNS) in an animal model of focal cerebral ischemia, using a novel stimulator device. Ischemia was achieved by transient proximal middle cerebral artery occlusion in XX rats with a nylon monofilament introduced in the internal carotid artery. The vagus nerve stimulator was housed subcutaneously in the abdomen and tunnelled up to the cervical part of the nerve. All rats were clinically examined and half of them were stimulated everyday for 2 weeks. At post-mortem brains were fixed to perform histological, immunohistochemical and molecular analyses. The neurological examination revealed an impairment in all treated rats. The damage seemed to be more consistent in not stimulated rats. Histological examinations did not show classic signs of CNS ischemia, whilst immunohistochemical analyses revealed higher GFAP and IBA1 expression in treated ischemic rats in comparison to sham animals. Molecular microarray analysis revealed differences in mRNA expression in many cellular pathways (neuroactive ligand-receptor interaction for example) between controls and ischaemic groups, although the investigations are still underway. Our preliminary data indicate that 2 weeks of VNS is feasible without any side effects, although the behavioral improvement needs to be studied deeply and with a greater number of animals. To sum up, our brain ischemia animal model should be improved since histological evidence of necrosis has not been achieved yet; however, immunohistochemical and molecular results highlight a putative neuroprotective action of the applied VNS device., Rehabilitation of patients suffering of muscle denervation is still a challenge for clinicians. In past years the treatment consisted essentially in prescription of orthotics and/or walking aids. This approach is still useful but recently, electrical stimulation for denervated muscle showed the possibility to evoke muscular tonic contractions and recover muscle trophism also in long term denervation. This offers the chance to include electrical stimulation in diagnostics, treatment and follow up evaluations of this condition. In this presentation, based on an example case of neuralgic amyotrophy, we discuss the rehabilitative strategies and propose our clinical approach to this kind of patients., The neuralgic amyotrophy (NA) o Parsonage-Turner syndrome is a rare disease of the peripheral nervous system characterized by sudden onset of severe pain in the upper limbs, followed by rapid weakness, atrophy and motor slow remission, which can last months to years. It has an idiopathic and hereditary form. The NA occurs at any age, but is most common in the 3-7 decade of life and among men. Some patients experience a relapsing/remitting course with symptom-free intervals while others have an incomplete recovery with persisting neurologic deficit. In 50% of cases, the NA is associated with a point mutation or duplication of the susceptibility gene on chromosome 17q25.3 SEPT9. Diagnosis is based on typical clinical signs and exclusion of other diseases by laboratory testing, electromyography, imaging of the cervical spine and brachial plexus. Pain control using a combination of long-acting opioids and NSAIDs associated to oral prednisone during the first weeks of an attack and accelerate recovery. Rehabilitation therapy is also important in NA. We present a case of 54 years old man with NA. When he was 49 years old, he started complaining of sudden neck pain radiating to the left shoulder and subsequent weakness of the limb. The patient presented a hypothrophy and hypotonia of flexor-extensor of the left shoulder muscles, associate a lack of tactile sensitivity of the lateral surface of the left arm, consequently the patient decide to suspend the driving. He performed laboratory tests, which were normal, an EMG of the upper limb which confirmed the presence of a peripheral nervous denervation and CT of the neck and chest that was normal. The patient was treated with oral cortisone without benefits. Due to the worsening symptoms immune globulin and cortisone were administered and the patient began physiotherapy which was later associated with muscle electrostimulation (ES), massage and physiotherapy obtaining a reduction in pain after 6-7 months. Patient had initially two and a half hours of ES once per day to muscle affected with exponential monophasic currents by “Siemens Neuroton 626 “device. One year and a half after, the patient was treated with “Miostim” device applying biphasic currents and associating massage, employs assisted exercises, exercises against resistance, and dynamic splints for finger). Currently the patient has only occasionally or no pain. He returned to work and restarted to drive. He has mild weakness bilaterally on extensors of the wrists (4/5), more to the left arm. On the left the patient has also a deficit of the flexor muscles (4/5) and the drt are hyporeflexive. The prognosis of NA is variable: usually patients recover 70-90% of their previous motor function after 1-2 years. In general, the result in our patient is satisfactory. This case shows a successful treatment including physical therapy and ES in patients with NA., The Vienna Strategies for Functional Electrical Stimulation (FES) of human muscles in neuromuscular disorders and aging were inspired by conventional protocols of neuromuscular stimulation (usually called NMES, Neuro Muscular Electrical Stimulation), but succeed to be applied to the extreme case of degenerating muscles due to long term irreversible denervation when some of the dogma of NMES/FES were violated.1-4 Long term denervated muscle undergo several stage of excitatory and contraction disorders that call for specialized stimulation protocols, in particular long stimuli in the range of 100-300 msec, that is hundreds of time long impulses. However, when excitability is recovered, shortening of the impulse allow to reach the most desirable sustained contraction by train of impulses delivered for 1-2 sec at 30Hz and thus Functional movements of the legs. That is achieved only if the inter-pulse OFF time is shortened to 10 msec and the pulse to 30-40 msec. We would like to stress that such a pattern of stimulation is very different from the conventional stimulation pattern of innervated muscle (that is, < 1 millisec at 50-100 Hz) and thus it can be used to demonstrate that the responding muscle are NOT reinnervated. Anyhow, protocols of progressive loading of the muscles can be thereafter prescribed to increase muscle resistance and strength. As to the stimulation of human muscle in aging,5-8 it is here enough to say that the conventional NMES strategies for muscle resistance and strength are applied, but increasing the safety measure to avoid tendon, muscle and joint lesions.

Neuromuscular electrical stimulation (NMES) usually involves the application of intermittent stimuli over the muscle with the aim to produce strong contractions through the activation of intramuscular nerve branches. The main physiological uniqueness of these electrically-evoked contractions is that motor unit recruitment is different from a voluntary action, as it has been shown to be spatially fixed, temporally synchronous, mainly superficial and non-selective.1 Indeed, NMES leads to the activation of both slow and fast motor units even at relatively low force levels. This specific motor units activation pattern has been associated with an exaggerated metabolic demand and a greater muscle fatigue as compared with voluntary exercise performed at the same intensity,1 thereby limiting the widespread utilization of NMES in clinical settings. It has been recently highlighted that NMES can also induce significant muscle damage as illustrated by major histological alterations such as z-lines disruption and macrophage infiltration as well as by the prolonged decrease in voluntary force production capacities.2 In the first part of the presentation, we will provide an overview of the main physiological consequences of the peculiar motor unit recruitment associated with NMES and provide some recommendations for limiting or preventing the corresponding “adverse” effects of NMES. Over the last two decades, chronic NMES application has been used as an effective way of improving muscle strength in both healthy humans and athletes. The magnitude of the strength gains has been related to the level of electrically evoked force. Given that the subject’s tolerance of the electric current determines the force evoked by NMES, there is a large inter-individual variability in NMES response. Of interest, the time course of neuromuscular adaptations to NMES training appears similar to that taking place in response to voluntary strength training programs. Indeed, adaptations within the central nervous system occurred in the early phase of NMES training as illustrated by the increased electromyographic activity and neural activation,3 enhanced V-wave amplitudes,3 and significant cross-education effects.4 These findings clearly indicated that NMES does not actually bypass the central nervous system due to the activation of both muscle and cutaneous afferent fibers. In addition, long-term NMES training programs (i.e., >6-8 weeks) may further induce muscle hypertrophy, improve muscle oxidative capacity and result in a fast-to-slow muscle fiber type transition.5 Surprisingly, the relevance of such phenotypic adaptations for the translation to endurance performance that is particularly important for sport and daily activities remains to be demonstrated. The second part of the presentation will address how and to what extent NMES-induced neural and muscle adaptations might be relevant in a clinical context. We will also suggest potential directions for future implementation of NMES in inactive patients with advanced disease., In people with spinal cord injuries (SCI) autonomic dysfunction is related with several conditions which increase cardiovascular risk: abnormalities in blood pressure, heart rate variability, arrhythmias and an altered cardiovascular response to exercise. If all these factors limit the performance in physical activity in the SCI population, several evidences in literature show that physical inactivity is the main independent risk factor for the development of cardiovascular diseases.1-3 Aims of the study was the monitoring of cardiovascular performance parameters, respiratory parameters and muscular working capacity of a population of disabled athletes with complete spinal cord injury in chronic phase. 29 athletes, performing agonist sport were evaluated. The characteristics of the population are: a complete spinal cord injury classified as ASIA A (13 persons had a neurological level above Th6 and 16 a neurological level below Th6), 25 males and 4 females; age 42.24 ± 12.40 years; BMI 23.20 ± 3.26; time to the lesion (the spinal cord injury) 17.14 ± 12.30 years. Assessments (clinical evaluation, blood tests, spirometric test, incremental test at the crank ergometer with monitoring of cardio-respiratory parameters) were carried out in 2008 (t0) and after 6 year in 2014 (t1). By multiple regression we analyzed at t0 and t1 the contribution on maximum oxygen consumption parameters (VO2max) of variables as age, Body Mas Index (BMI), lesional level, years to the injury and weekly hours of training. At t0 the contribution on VO2max parameters of the other variables taken into account was statistically significant (p = 0.0075) for the lesional level. The correlation between VO2max and the lesional level was confirmed by analysis of variance (ANOVA) (p = 0.096). This means that the lower the lesional level the higher the VO2max in subjects who practice sports. At t1 we achieved a statistically significant correlation between VO2max parameters and weekly training hours (p = 0.0091), therefore in the long term in our subjects an increase in VO2max is related to the increase in weekly training hours. We also checked at t1 a statistically significant correlation between VO2max and BMI, with an increase in VO2 max correlated with a reduction in BMI (p = 0.005) of our athletes. The continued practice of physical activity is critical in improving cardiovascular performance in people with spinal cord injuries, especially in most affected persons. In the SCI population in chronic phase, hours of practice in sports activities and maintaining an adequate BMI are extremely important for saving cardiovascular fitness., Long standing lower motor neuron denervation of skeletal muscle is known to end in fibrotic degeneration of muscle tissue.1 However, long term survival of a subset of skeletal myofibers also occurs.2,3 We performed transverse and longitudinal studies of SCI patients suffering with complete Conus and Cauda Equina Syndrome and of sedentary and active seniors which included analyses of muscle biopsies from the quadriceps muscle. Surprisingly, we discovered that human denervated myofibers survive years of denervation after full and irreversible disconnection from their motor neurons.1 Open is, however, the extent of contribution of muscle fiber regeneration to these observations.4 We found that atrophic myofibers could be rescued by home-based Functional Electrical Stimulation (h-bFES), using purpose developed stimulators and electrodes.5,6 Although denervated myofibers quickly lose the ability to sustain high-frequency contractions, they continue to respond to single, very long impulses (up to 200 millisec) that are able to recover enough muscle excitability to allow for re-emergence of tetanic contractions. A description of the very early changes in humans are hampered by a paucity of patients suffering complete Conus and Cauda Equina Syndrome, but the cohort enrolled in the EU RISE Project has shown that even five years after SCI, severe atrophic myofibers, with a peculiar cluster reorganization of myonuclei,3 are present in human muscles and respond to h-bFES.5,6 Thus, human myofibers survive permanent denervation much longer than generally accepted and they maintain the capacity to respond to h-bFES beyond the stage of simple atrophy. Furthermore, long-term denervation/reinnervation events occur in elderly,7 and is part of the mechanisms responsible for muscle aging and again h-bFES was beneficial in delaying aging decay.8,9 Indeed, physical exercise is known to have beneficial effects on muscle trophism and force production modulating signaling pathways involved in fiber type plasticity, muscle growth and mitochondria respiratory efficiency. It has been shown that the decrease of muscle mass and strength observed in aging is linked to intracellular and extracellular abnormalities, that is, sarcoplasmic reticulum-to-mitochondria malfunctions and extracellular matrix metabolism, respectively. When healthy seniors are exposed to regular neuromuscular ES training for a period of 9 weeks outcomes are an increase in muscle strength and muscle fibers and, most importantly, an increase of fast fibers, the more powerful of skeletal muscle motor units.8,9 Electron microscopy analyses show remodelling of mitochondrial apparatus as a consequence of fusion phenomena that are consistent with adaptation to physical exercise. Altogether the results indicate that the ES-dependent beneficial effects on muscle mass and force are associated with changes in mitochondrial-related proteins involved in Ca2+ homeostasis, providing new targets to develop therapeutic strategies to promote healthy aging., Spinal cord injury causes paralysis and subsequent muscle wasting and loss of muscle function, which are especially severe after complete and permanent damage to lower motor neurons. However, long term survival of a subset of skeletal myofibers also occurs.1 We performed transverse and longitudinal studies of SCI patients suffering with complete Conus and Cauda Equina Syndrome2 and found that atrophic myofibers could be rescued by home-based Functional Electrical Stimulation (h-bFES), using purpose developed stimulators and electrodes.3 The recommended parameters and time intervals are suggestions based on the EU project RISE and our clinical experience.2,3 They should be adapted to personal needs of patients in respect to time span of denervation, and condition of muscle and function. Patient training should start with single twitch stimulation with an impulse duration (ID) of 150ms and an impulse pause (IP) of 500ms for the first 2 months (can be reduced if the time of denervation is under 6 months) and 120ms ID, 400ms IP, after 2 months to excite denervated muscle fibers still hard to activate. After eliciting sufficient muscle reaction the next training phase implements tetanic bursts of a stimulation duration (SD) of 3s and a stimulation pause (SP) of 3s with impulses of 40ms ID and 10ms IP after 2 months of stimulation – in addition to the single twitch program - to increase muscle fiber diameter, muscle mass, density and force with leg extensions (after 2-5 months) with and without additional weights on the subjects ankle. If a good condition is achieved (depending not only from the training also from the time span of denervation) the strength training can be replaced with stand-up, stepping and walking exercises in parallel bars performed with continuous stimulation controlled by an external switch. In conclusion, human myofibers survive permanent denervation much longer than generally accepted1-5, and they maintain the capacity to respond to h-bFES beyond the stage of simple atrophy2,3., The Stimulette den2x is a high performance 2-channel electrotherapy stimulator, specialized to be used for activating flaccid paralyzed denervated muscles. Damages of the lower motor neuron in conus-cauda-lesion or peripheral nerve injury cause dramatic changes in the affected muscle. With adequate stimulation parameters those changes can be stopped or even reversed.1,2 This bridges the time gap until reinnervation occurs in nerve injury. In conus-cauda-lesion, where we usually see severe muscle atrophy, it preserves/recovers muscles mass improving its trophic state, thus helping to prevent pressure sores. In this workshop the changes due to denervation, and the constrains for results of adequate electrical stimulation will be discussed. Furthermore the practical application of the stimulation device Stimulette den2x, now commercially available, will be fully demonstrated with the help of voluntary persons and patients. The EU Project RISE demonstrated that home based FES of denervated muscles is a secure and effective home therapy. Benefits of stimulating denervated muscles are: 1. Recovery of tetanic contractility; 2. Restoration of muscle fibre structure; 3. Recovery of fibre size and muscle mass; 4. Better skin condition; 5. Reduced risk of pressure sores; 6. Improved cosmetic appearance of lower extremities; 7. Increased self-esteem. Furthermore, if standing upright is accomplished: 8. Improved cardiovascular fitness; 9. Unloading of seating surface. The conclusion of the RISE project was that a commercial electrotherapy device for home based FES was a priority. The Stimulette den2x by Dr. Schuhfried is the first device that delivers the needed power and technical requirements to fullfil the clinical requests. The following parameters are programmable: Impulse amplitude: max +/- 300 mA; Impulse waveform: rectangular / ramp shaped (3 different waveforms); Impulse duration ID: 10 ms—200 ms; Impulse pause IP: 1 ms-2 s; Surge duration: 100 ms—11 s; Rise: 5 % - 100 % surge duration; Decay: 5 % – 100 % surge duration; Surge interval: 0 ms—11 s; Treatment duration: 1—59 min; all currents are biphasic. The Switchbox: The Switchbox has been developed to enable flaccid paraplegic patients to practice standing, stepping and a type of „walking“ at the parallel bars. Functional Electrical Stimulation of denervated muscles — a novel therapeutic option after peripheral nerve lesion is a realistic option. In conclusion, the Stimulette den2x represents a major breakthrough in FES., Rehabilitation treatment is still a challenge for clinicians in patient suffering from muscle atrophy following spinal cord Injury and/or peripheral neuropathies. Electrical Stimulation (ES) is a discussed option, but it plays in our opinion an important a role at least to maintain muscle trophism of denervated muscles and recover from atrophic innervated muscles.1-3 In our hospital, functional and electrical stimulation tests are part of the standard evaluation in patients treated with electrical stimulation for denervated muscle after peripheral nerve injury. However, to better explain the effects of ES and verify the efficacy of the treatment, muscle imaging could help clinician for the follow up of this kind of patients. In this presentation we discuss the usefulness and use of different type of muscle imaging (MRI, CT, dynamic echomyography) to assess muscle tissue health in clinical rehabilitation perspectives.4-6 We will present case reports to offer the opportunity to discuss rehabilitative pathwaies for diagnostics and rehabilitation of patients suffering of peripheral denervation, a condition that is still a challenge for clinicians. In particular we would like to evaluate the opportunities of the Quantitative Muscle Color Computed Tomography (QMC-CT), a quantitative imaging analysis introduced by our group to monitor skeletal muscle. Validation of QMC-CT will provide physicians an improved quantitative tool to diagnose the condition of skeletal muscle during rehabilitation of mobility-impaired persons, so that managements can be better prescribed, evaluated and altered where needed., The cellular basis of age-related tissue deterioration remains largely obscure. The ability to activate compensatory mechanisms in response to environmental stress is an important factor for survival and maintenance of cellular functions. Autophagy is activated both under short and prolonged stress and is required to clear the cell of dysfunctional organelles and altered proteins. We report that autophagy in muscles declines with ageing and its inhibition correlates with age-dependent muscle loss and weakness. Specific autophagy inhibition in muscle has a major impact on neuromuscular synaptic function and, consequently, on muscle strength, ultimately affecting the lifespan of animals. Inhibition of autophagy also exacerbates aging phenotypes in muscle, such as mitochondrial dysfunction, oxidative stress, and profound weakness. Mitochondrial dysfunction and oxidative stress directly affect acto-myosin interaction and force generation but show a limited effect on stability of neuromuscular synapses. Mitochondria shape is also a critical factor for sarcopenia and for systemic ageing. Mechanistically, mitochondria control a cascade of signalling events that induce muscle secretion of myokines that cause systemic ageing and premature death.1-4, Physical medicine therapies are first line of intervention, with pharmacologic prior to surgical treatments for several musculoskeletal diseases, such as low back pain. Herbal cataplasms containing a rubefacient substance, (Cayenne pepper, CP) are directly applied to the skin at the site of the painful areas provoking a hyperemic response, that involves both epidermis and muscle tissue nociceptor fibers, with beneficial analgesic effects. Capsaicin is the most abundant capsaicinoid present in the Cayenne pepper and it is an agonist of Transient Receptor Potential Vanilloid 1 (TRPV1). This treatment is generally well tolerated, but data on its possible side effects and secondary targets are missing. We tested 20-min application of 5% Cayenne pepper cataplasm (CPC) on healthy subjects, monitoring its effects on serum levels (before and 0.5, 1, 3, 6, 24 hrs after application) of general Laboratory parameters (hemogram, CRP, sedimentation, CK, albumin, cortisol), pro-and antiinflammatory cytokines (TNF-alpha, IL-1β, IL-6, TGF-β1) biomarkers specific for blood vessels damage (leukotriene B4, E-selectin, P-selectin, VCAM-1), and a panel of selected miRNAs possibly implicated in the cellular processes modulated by Caspaicin topical treatment.1-3 Specifically, we analysed miRNA regulating TRPV1 transcription (miR-199a, and miR-199b), those mediators of inflammation (miR-155, miR-21, miR-146a), intracellular Ca2+ homeostasis (miR-25), endothelial cell damage (miR-126), cardiac and skeletal muscle homeostasis (miR-1, miR-133, and miR-206). No significant changes in the serum levels of tested cyokines or Laboratory parameters have been observed over the analysed time period. Interestingly, changes of the plasma levels of c-miRNA regulating Th1>Th2 inflammatory response and TRPV1 (specific pharmacologic target of Capsaicin) were detected. These results suggest that 5% Munari cataplasm seems to be a safe treatment targeting specific receptor responsible for pain sensation. In addition, circulating miRNAs are novel good candidate biomarkers for testing and monitoring treatment’s effects in patients affected with Low Back Pain. Further studies are needed to investigate the immediate and long-term effects of repeated CPC applications as well as to understand the intersecting underlying mechanisms activated by Capsaicin and other identified factors, in order to further validate them for physical medicine therapies., Endocannabinoids are endogenous lipid mediators with wide range of biological effects similar to those of marijuana. They exert their biological effects via two main G-protein-coupled cannabinoid receptors, the CB1 (cannabinoid receptor 1) and CB2 (cannabinoid receptor 2). Cannabinoid receptors have been localized in the central and peripheral nervous system as well as on cells of the immune system, but recent studies gave evidence for the presence of cannabinoid receptors in different types of tissues.1,2 Their presence was supposed in myofascial tissue, suggesting that the endocannabinoid system may help resolve myofascial trigger points, suppressing proinflammatory cytokines such as IL-1beta e TNF-alpha and increasing anti-inflammatory cytokines.3,4 However, until now the expression of CB1 and CB2 in fasciae and in fascial fibroblasts has not yet been established. In this work small samples of fascia were collected from volunteers patients: for each sample were done a fibroblast cell isolation, immunohistochemical investigation (CB1 and CB2 antibodies) and real time RT-PCR to detect the expression of CB1 and CB2 and evaluation of gene expression of CB1 and CB2 receptors after fibroblasts mechanical stimulation. The immunostaining results demonstrate the expression of CB1 and CB2 on fascial fibroblasts and fascial tissue. In the tissue not all the fibroblasts are positive, whereas the isolated and expanded cells are homogeneous. These results are confirmed by the real time PCR where the specificity of the reaction on fibroblasts and fascial tissue is the same, but the amount of expression in the tissue is lower, for both CB1 and CB2. The mechanical stimulation has shown that there is an increase of CB2 expression on fibroblasts. This is the first demonstration that the fibroblasts of the muscular fasciae express CB1 and CB2. These results could represent a new target for drugs to care fascial fibrosis and inflammation. The presence of the endocannabinoid system in the fascial fibroblasts can also explain the efficacy of cannabis to care myofascial pain and the observation that a mechanical stimulation has given an increase of receptor gene expression could explain the possible stimulation during manipulative treatments and exercises.5 More studies about the interactions between fibroblasts, extracellular matrix and CB1 and CB2 receptors could help to understand the role of these receptors on myofascial pain., Skeletal muscle repair goes through a modulation of several stages, which are mainly accomplished through changes in the activation profile of macrophages. This process results in changes in the phenotype and function of involved cells and macrophages, which play a key role in this progression and are considered the targets for therapeutic intervention.1,2 Mitochondria also exert a crucial modulatory effect on inflammatory macrophages pathways, leading to the production of cytokines (Mitogen Activated Protein Kinases and Nuclear Factor-Kappa β) pathways. When an inflammatory stimulus triggers macrophage activation, the mitochondria amplify these pathways, resulting in increased production of cytokines and inflammatory mediators. Over the last ten years, many studies demonstrate that the employment of the laser therapy modulates many biochemical processes, especially the decrease of muscle injures, the increase in mitochondrial respiration and ATP synthesis, crucial to accelerate the healing process. However, nowadays there is no consensus over the best laser protocol to employ in the clinical practice in order to obtain the most efficient biological response. For this reason, many in vitro studies focus their attention on the highest effect on mitochondria by laser light. Among the most clinical employed wavelengths, it is already known that red and infrared laser lights stimulate photochemical and photophysical events in mitochondria, thus resulting in increased mitochondrial membrane potential and higher enzyme activity in the respiratory chain. It is possible to observe structural changes, such as the formation of giant mitochondria through the merging of membranes of smaller and neighbouring mitochondria, which lead to higher levels of respiration and ATP to cells. It has also been demonstrated that laser therapy improves enzyme activity of the complex IV (cytochrome c oxidase) in skeletal muscle mitochondria. This effect is crucial since the oxidative capacity of muscle fibres is related to the density of mitochondria, able to oxidize glucose, fatty acids and proteins for ATP synthesis during muscle contraction. To optimize muscle recovery, when adding laser therapy to low intensity exercises, it is possible to foster this mechanism working on mitochondrial biogenesis, both to favour aerobic metabolism and to reduce muscle fatigue from metabolic origin.3-6 MTT assay on myocytes assesses an increased mitochondrial activity and cell activation after laser treatment. In addition, it is possible to observe a clear reduction in Tumor Necrosis Factor-a production 24 hours after the irradiation of activated macrophages. So, thanks to laser therapy muscle performance could be increased reducing its fatigue; the most accredited and studied mechanisms to this specific behaviour are: i) enhance mitochondrial activity, ii) phosphocreatine resynthesis and iii) mitochondria lactate oxidation. Although in vitro studies offer the possibility to standardize the obtained results, thanks to their cellular and molecular highly reproducible models, the results of such studies cannot be directly correlated with clinical outcomes. Nevertheless, the knowledge of the effect of laser therapy on the mitochondria contained in different muscle cell types is of paramount importance for the design of in vivo protocols that can exert more effective modulation of the muscle repair process., Chronic low back pain (CLBP) is a disabling condition affecting a majority of people of the western countries. It deeply affects the quality of life as it is often linked to multidimensional disturbances such as poor sleep, mood disorders, chronic fatigue and joint pain. There is no other condition with higher social and economic costs. It has been reported that only a minority of patients with gut inflammation suffers from intestinal symptoms. In a previous paper it was proposed that gastrointestinal disturbances, beyond mechanical issues, could be overlooked in the management of these patients. Dietary changes were successful in the positive resolution of the described clinical case. In this paper we further test this hypothesis. We measured on 5 subjects specific parameters related to gastrointestinal and digestive physiology that have been associated with metabolic and immune related pathological conditions. Specifically we tested the levels of zonuline (related to intestinal permeability) the presence of undigested substances, ph and the colonization of specific bacteria (symbiotic vs pathoghenous). Inflammation in the gut can lead to altered mucosa permeability indeed. The entrance in the blood stream of abnormal molecules activates the immune system in a cascade of events affecting remote systems and possibly the integrity of structures like the neuromuscolar junction or the pathways of energy production. Conditions that are currently managed by orthopaedists, reumatologists or neurologists could benefit from a screening of the gastrointestinal functionality., It is well known that repeated bouts of exercise (i.e. exercise training) lead to an elevated content of mitochondria within muscle. This adaptation confers metabolic advantages during exercise, such as an increase in the aerobic metabolism of lipids, reduced glycogen usage, and diminished lactate production. The molecular basis for this increase in organelle content involves the activation of PGC-1α along with numerous transcription factors which increase the expression of nuclear genes encoding mitochondrial proteins. Among these are Tfam, the transcription factor which mediates mtDNA replication and transcription, in an effort to coordinate the nuclear and mitochondrial genomic responses to the exercise signals. These organelle synthesis processes (termed biogenesis) have been well-studied, and reviewed recently.1 On the other hand, it is also recognized that the steady state mitochondrial content of muscle is determined not only by rates of synthesis, but rather by organelle turnover, represented by a balance between synthesis and degradation. The degradation process is termed mitophagy. In contrast to biogenesis, our understanding of mitophagy in muscle is in its infancy. Mitophagy involves the activation of the general autophagy pathway within the cell, where the ultimate target for degradation is the dysfunctional mitochondrion. Targeting mitochondria involves tagging the organelle for degradation by ubiquitination, followed by its engulfment within an autophagosome for fusion to a lysosome, and subsequent proteolysis. We have previously shown that a single bout of exercise initiates mitophagy flux signaling, measured as the activation of kinases which trigger autophagy, along with localization of LC3-II and p62 on the surface of the organelle. We found that the degree of mitophagy flux enhanced by exercise was PGC-1α-dependent, such that the absence of the coactivator led to reduced mitophagic responses to exercise. Thus, PGC-1α is involved not only in organelle biogenesis, but also in its degradation.2 In contrast to the enhanced mitochondrial content in muscle in response to exercise, aging is a progressive condition in which mitochondrial content and function, along with the level of PGC-1α, are reduced in muscle, contributing to altered metabolism and decrements in muscle mass.3 In addition, while muscle adaptations are certainly possible in response to exercise, the biogenesis adaptations to standardized workloads is not as robust with age, as it is in younger subjects.4 Thus, while previous work has documented blunted stages of biogenesis in aged muscle, no research has documented the degree of change in mitophagy. The prevailing dogma suggests that mitophagy is decreased in aging muscle, however limitations in methodologies preclude this conclusion. Furthermore, how chronic exercise may affect mitophagy in aged muscle remains unexplored. Thus, we have examined the effect of aging and chronic exercise on mitophagy flux using 6 and 36 month old Fisher 344 Brown Norway rats that serve as an excellent model of aging skeletal muscle. To invoke comparable levels of chronic exercise, the animals were implanted with a stimulator to activate the peroneal nerve which innervates the tibialis anterior muscle to induce chronic contractile activity (CCA; 3hrs/day, 9 days). The contralateral limb served as control. Colchicine is a microtubule inhibitor which interferes with the transport of the autophagosome to the lysosome for degradation. Thus, administering this drug for 3 days (0.4 mg/kg/day) allowed us to measure mitophagic flux when levels of p62 and LC3-II are compared to vehicle-treated animals. To evaluate mitophagy, intermyofibrillar mitochondria were isolated from the TA muscle and protein localization was assessed by immunoblotting. As expected, aged animals exhibited reduced mitochondrial content and an attenuated adaptation to CCA in agreement with previous work.4 Colchicine successfully inhibited autophagy in our model and allowed for the quantification of mitophagy flux. In young animals following the mitochondrial adaptations to 9 days of CCA we observed decreased mitophagy,5 consistent with the idea that improved mitochondrial content or function after CCA obligates lower organelle degradation rates. In contract, mitophagy flux was higher in muscle of aged animals,5 in contrast to suggestions from the literature, and the attenuation of mitophagy as a result of CCA was less pronounced. These high rates of mitophagy may contribute to the age-related loss of mitochondrial content, but when combined with a reduced capacity for biogenesis, this pattern of organelle turnover within aged muscle is insufficient to maintain the high quality of mitochondria compared to muscle from younger animals. Our data also fortify the concept that exercise is a useful therapy to modify mitochondrial turnover rates, in an effort to sustain, or enhance, the healthiest mitochondrial pool within skeletal muscle., Preserving mobility is central to maintaining a high quality of life and participation in activities to be fully independent in the community.1 Unfortunately, aging is associated with a progressive decline in mobility, as well as cognitive and physical function, leading to a loss of independence. As diverse as the etiologies of physical disability are, a growing body of evidence strongly implicates chronic low-grade systemic inflammation as playing a significant role in contributing to sarcopenia and associated functional decline.2,3 A variety of endogenous factors (e.g., adiposity) and exogenous factors (e.g., lifestyle habits) appear to contribute to the rise in systemic levels of inflammation seen with aging.4 To date, few therapeutic approaches have been specifically identified to reduce chronic systemic inflammation with the goal of reducing pain levels and improving functional performance in seniors. There are, however, a number of promising approaches that have emerged during the past decade that appear capable of targeting chronic systemic inflammation. Given the increasing number of older adults with elevated levels of systemic inflammation who are at risk for functional decline, new therapies are urgently needed to reduce systemic inflammation levels and improve or maintain functional ability in this high risk population. Thus, the purpose of this presentation is to provide an overview of promising therapeutic approaches, including lifestyle interventions, hormonal replacement, natural compounds, and pharmaceutical agents, to avert levels of chronic systemic inflammation during aging and preserve function in older adults., Iron dyshomeostasis (high cellular and low systemic levels) are strong risk factors in the development of disease, disability and premature death. Systemic iron deficiency (anemia with old age) impairs oxygen carrying capacity, while in contrast increased cellular levels can increase DNA lesions. Disturbances of iron metabolism including uptake, export, and storage have shown to play a causal role in cellular and mitochondrial dysfunctions with age and disease. Iron is found in several forms: heme iron (i.e., haemoglobin, myoglobin) and non-heme iron (i.e., Ferritin). A distinct fraction of chelatable non-heme iron is referred to as the labile iron pool, which comprises less than 5% of total cellular iron. Labile iron consists of Fe2+ and Fe3+ ions associated with a variety of small molecules, including organic anions, polypeptides, and phospholipids. Labile iron can participate in Fenton reactions, producing highly destructive hydroxyl radicals, which are thought to be a major contributor to the formation of DNA mutatons. Cellular iron acquisition occurs through iron import proteins such as transferrin receptor (TfR1), divalent metal transporter-1 (DMT1), and Zip14, whereas cellular iron export is mediated by ferroportin (FPN), the only known iron exporter in mammals. The mitochondria contain mitoferrin (Mt iron importer), iron storage proteins such as frataxin and Mt ferritin (MtF) (which binds with iron), and ABCB7 (a heme export protein), all known to play an important role in the storage and regulation of Mt iron. We and others have found that in animals and humans, labile iron and non-heme iron increases with age and is associated with elevated expression of ferritin. In contrast, transferrin receptor 1 (TfR1; cellular iron import protein) showed a dramatic down regulation with age. In addition, mitochondrial iron levels effect Mt permeability transition pore opening susceptibility (i.e., Ca2+ retention capacity) in mitochondria from old animals. Further studies to better understand iron metabolism with aging are warranted to design interventions to reduce DNA lesions., Depletion of calcium (Ca2+) from intracellular stores triggers store-operated Ca2+ entry (SOCE), a ubiquitous mechanism that allows recovery of Ca2+ ions from the extracellular space. To date, the subcellular location for SOCE in skeletal muscle fibers has not been unequivocally identified. Here we show by electron microscopy (EM) that 1 hour of incremental treadmill running of mice (from 5 m/min to 25 m/min) drives a striking remodeling of the existing sarcotubular system in skeletal fibers leading to formation of previously unidentified junctions between sarcoplasmic reticulum (SR) and transverse-tubules (TTs). In addition, using immunohistochemistry, immunogold labeling for EM, and western blot analyses we demonstrate that these new SR-TT junctions contain the molecular machinery that mediate SOCE: a) stromal interaction molecule-1 (STIM1), which functions as Ca2+ sensor in the SR, and b) Ca2+ permeable Orai1 channels in TTs. Finally, we used a stimulation protocol (30 x 1s-60Hz pulses every 5 seconds) to compare susceptibility to in vitro muscle fatigue of EDL muscles from either control or exercised mice. EDL muscles from exercised mice exhibited an increased capability of maintaining contractile force in presence of 2.5 mM extracellular Ca2+, that was abolished by either the presence of SOCE inhibitors (BTP-2 and 2-APB) or by equimolar replacement of extracellular Ca2+ with Mg2+. We propose that exercised-induced formation of newly formed SR-TT junctions containing STIM1 and Orai1 proteins function as Ca2+ Entry Units (CEUs), structures that provide a pathway to rapidly recover Ca2+ ions from the extracellular space during repetitive muscle activity.., The ERG1 potassium channel is known to participate in repolarization of the cardiac action potential.1 However, we reported detection of this protein in the Gastrocnemius muscle of mice experiencing atrophy as a result of both disuse (i.e., unweighting) and cancer cachexia while it was not detected in the Gastrocnemius muscles of appropriate control animals.2 In subsequent studies, we showed that ERG1 participates in muscle degradation by enhancing ubiquitin proteolysis through increased abundance of the E3 ligase, MuRF1.3,4 However, to our knowledge, ERG1 has not been reported in human skeletal muscle. Here we have used immunohistochemistry and confocal microscopy to image ERG1 protein with a fluorescent marker and report detection of ERG1 immunofluorescence in the Rectus abdominis (RA) muscle of adult humans. Interestingly, we detect statistically greater immunofluorescence (67.0%; p≤0.01) in the RA muscle of people having cancer cachexia (n=6) than in the same muscle of age-matched healthy adults (n=7). We detect ERG1 immunofluorescence at low levels only in the RA muscle of young adults (n=4); however, our results show that the signal trends toward greater fluorescence (11.0%) in the RA muscle of healthy aged adults than in that of the younger ones. Although the difference in ERG1 immunofluorescence in the healthy aged and young adult RA muscle is not statistically significant, Power analysis of the data demonstrates that an increase in sample size to 46 (23 each group) from the current size of 11 people would produce a significant difference in the data. Indeed, our data suggest that ERG1 may be related to the skeletal muscle loss that occurs with cachexia and aging in humans., Tubular aggregates (TAs), ordered arrays of sarcoplasmic reticulum (SR) tubes, form in ageing fast twitch fibers of mice, preferentially in males. TAs are also the main morphological alteration in biopsies from patients affected by TA Myopathy (TAM). TAM has been linked to mutations in the genes encoding for STIM1 and Orai1, the two proteins that mediate store-operated Ca2+ entry (SOCE), a mechanism that allows recovery of extracellular Ca2+ when the SR is depleted. We have previously shown that: i) TAs contain SERCA1 and CASQ1, two proteins involved in reuptake and storage of Ca2+ in the SR; ii) tubes of TAs appear linked by small bridges. Here, we combined different experimental approaches - electron and confocal microscopy (EM and CM), western blots (WB), and ex-vivo stimulation protocol (30 x 1s - 60 Hz pulses every five seconds) performed in inctact EDL muscles - to study localization and function of STIM1 and Orai1 in muscle containing TAs. In EDL muscles from mice of 4 and 24 months of age: i) ageing causes STIM1 and Orai1 to accumulate in TAs; ii) the expression levels of both STIM1 splicing variants increase with age (STIM1S = 0.44±0.03 vs 0.66±0.08 A.U.; STIM1L = 0.38±0.05 vs 0.56±0.05 A.U. respectively for adult and aged mice); iii) EDL muscles from aged mice exhibit a decreased capability to maintain contractile force compared to adult mice (relative force after 10 tetani: 61.6±3.0%, and 52.7±4.3% respectively for adult and aged EDL muscles). Our findings suggest that accumulation of STIM1 and Orai1 in TAs, is dysfunctional as Ca2+ entry during repetitive stimulation is impaired in aged EDL muscles., The sarcomere is a highly organized structure that represents the functional unit of the contractile apparatus of striated muscles. The maintenance of both sarcomere integrity and the correct reciprocal arrangement between myofibrils and organelles, like nuclei and sarcoplasmic reticulum, costameres, etc., represent a crucial requirement that striated fibers must fulfill to efficiently accomplish repeated cycles of contraction and relaxation. Obscurin is a giant sarcomeric protein mainly localized at the M-band and, with minor distribution, at the Z-disk. The structural layout of Obscurin, which is based on the presence of different modular binding, adhesion and signaling motifs, allows the simultaneous interaction with sarcomeric and non-sarcomeric proteins, thus placing Obscurin in a key molecular crossroad to contribute to the overall muscle fiber architecture. Indeed, binding of Obscurin to Titin, Myomesin and OBSl1 provides an important structural support to sarcomere integrity and stability at the level of the M-band. In addition, the ability of Obscurin to interact with distinct members of the ankyrin family contributes to establish multiple molecular contacts between the contractile apparatus and sarcoplasmic reticulum, microtubules and costameres.1 We have recently reported studies with Obscurin KO mice suggesting a role of Obscurin in supporting fiber integrity following heavy exercise.2 These results will be presented and discussed also in relation to the recent identification of mutations in the Obscurin gene in patients with cardiac and skeletal muscle diseases.3, Loss of skeletal muscle mass and force aggravates age-related sarcopenia and numerous pathologies, like cancer and diabetes. The AKT-mTORC1 pathway plays a major role in stimulating adult muscle growth, however, the functional role of its downstream mediators in vivo is unknown. Here we show that simultaneous inhibition of mTOR signaling to both S6K1 and 4E-BP1 is sufficient to reduce AKT-induced muscle growth and render it insensitive to the mTORC1-inhibitor rapamycin. Surprisingly, lack of mTOR signaling to 4E-BP1 only, or deletion of S6K1 alone, is not sufficient to reduce muscle hypertrophy or alter its sensitivity to rapamycin. However, while not required for muscle growth, we report that S6K1 is essential for maintaining muscle structure and force production. Hypertrophy in the absence of S6K1 is characterized by a compromised ribosome biogenesis and the formation of p62-positive protein aggregates. These findings identify S6K1 as a crucial player for maintaining muscle function during hypertrophy., This work outlines the methods and applications of X-ray Computed Tomography imaging to analyze soft tissue and skeletal muscle density and volume in the context of modern challenges in the field of translational myology. The approaches described here use medical imaging processing techniques and computational methods to: quantify muscle morphology, illustrate changes with 3D models, develop numerical profiles specific for each individual, and assess muscle changes due to targeted medical treatment. Applications of these methodologies are employed: to depict subject specific muscle profiling associated with age, to illustrate and quantify muscle degeneration and its partial reversal via Functional Electrical Stimulation (FES), and to highlight recovery following total hip arthroplasty.1-5, The functional recovery from severe atrophy of long-term denervated muscle by h-bFES of DDM is a fact standing on sound foundations.1 Among them, a new quantitative muscle color computed tomography (QMC-CT)2,3 adds to functional evidence and muscle biopsy analyses, the results based on 2D (left panels) and 3D (right panel) clinical imaging analysis. We are extending the methods to managements of severe atrophy in oldest persons, which need simplified methods of evaluation, and safe, easy to performe rehabilitations at home.4 A major problem is to convince subjects to maintain volitional exercise at home. We are confident that strong evidence of structural improvements of muscles could motivate reluctant older persons to take home anti-aging full-body in-bed gym5 and functional electrical stimulation (FES) for mobility compromised elderly persons.4, Myotonic Dystrophy (DM1) is the most common form of adult-onset muscular dystrophy, but is missing circulating biomarkers as well as an effective rehabilitation protocol. In our work we aim to propose a clinical-molecular protocol to monitor rehabilitation therapy versus standard care in this common inherited muscle disorder. For all DM1 patients the maximum standard of care was achieved through special medical attention and locomotor study, cardio-respiratory and nutritional care, interview for psychological problems, quality of life, we investigated the role of serum MicroRNAs as biomarkers of the disease in order to correlate their levels with disease severity, multiorgan involvement and possibly the efficacy of physical rehabilitation program. We aimed to explore the cellular action of micro-RNAs that are non-coding-RNAs modulating gene expression, whose expression is dysregulated in DM1. In order to investigate the micro-RNA origin a initial aim was to measure the levels of muscle-specific myo-miRNAs (miR-1, miR-133a/b, miR-206) in muscle of 12 DM1 patients.1 Muscle fiber morphometry with a new grading of histopathological severity score were used to compare specific myo-miRNA level and fiber atrophy. We found that the levels of miR-1 and miR-133a/b were significantly decreased, while miR-206 was significantly increased as compared to controls. The histopathological score did not significantly correlate with the levels of myo-miRNAs, even if the lowest levels of miRNA-1 and miRNA-133a/b, and the highest levels of miRNA-206 were observed in patients with either severe histopathological scores or long disease duration. The histopathological score was inversely correlated with disease duration. Nowadays DM1 muscle biopsies are scanty, since patients are usually diagnosed by genetic analysis, our study offers a unique opportunity to present miRNA expression profiles in muscle and correlate them to muscle morphology in this rare multisystem disorder. Our molecular and morphologic data suggest a post-transcriptional regulatory action of myo-miRNA in DM1, highlighting their potential role as biomarkers of muscle plasticity. We explored in 10 patients (9 male and 1 female) during our new rehabilitative protocol we developed.2 Serum microRNAs appeared as biomarkers to monitor DM1 patients while in a protocol of aerobic lower extremity Functional Electrical Stimulation lower aerobic rehabilitation.2 We observed improvement of our patients during this exercise protocol and all microRNas decreased during rehabilitation (Figure). This study validate clinical use of microRNAs after the first discovery in MD1.3 In our investigations in muscle and serum, some microRNA (miR-1, miR-133a, miR-133b, miR-206) appeared promising in detecting changes in DM1 in natural history and during rehabilitation to correlate with functional outcomes, we found that reversal of muscle atrophy and onset of muscle regeneration in DM1 might be revealed by decreased microRNA levels. These circulating biomarkers were validated in this study in twelve DM1 cases., Several epidemiological studies have repeatedly shown a statistical association between life-long physical exercise and better preserved cognition later in life. This association was based on self-reports coded as variables which do not retain much quantitative variability. Some studies have used metabolic conversion to give a biological flavour to their findings. A few recent experimental studies have identified physical activity as a protective factor for cognitive decline. The role of physical activity as a protective factor has received more attention than other popular ways of stimulating the brain, e.g. cognitive stimulation. Studies have focused on discovering the biological mechanisms behind this effects and attention has been given to mitochondrial activity and the pathways by which ATP is produced, with a specific focus on aerobic exercise. Research studies have also compared the effects of acute vs chronic exercise. Experimental work has been carried out on acute exercise (i.e. single sessions) to explore the mechanisms involved and shed light on the biological underpinning of the beneficial effects of physical activity on cognition. This research has often involved young adults because of the opportunity to implement better manipulation of variables such as intensity and duration of exercise. Brain activity has been measured with Near Infrared Spectroscopy to study how brain function changes during acute exercise in an attempt to infer the mechanisms behind the long term effect of exercise. Because chronic exercise is associated with long term effects, there is a clinical interest to clarify the mechanisms that are involved in short and long term benefits due to exercise. Many studies have used exercise in combination with mixed interventions (e.g. diet and exercise, or cognitive stimulation and exercise), however. More recent experimental approaches have put forward possible explanations about the basis of the beneficial effects of exercise and suggested that physical activity triggers an improvement of cardiovascular fitness and improvement in cognition, but it is still unknown whether the two are causally linked. The implication is that cognitive benefits are the indirect outcome of cerebrovascular improvements. Other studies have suggested that physical activity increases neuroplastic mechanisms in humans, by fostering hippocampal neurogenesis, by regulating cortisol and BDNF and by enhancing motor-cortical plasticity as elicited by the TMS-based technique “cerebellar inhibition”. A crucial modulating factor appears to be played by individual genetic profiles, such as that for the ApoE gene. There is experimental evidence that suggests that the long term beneficial effects of exercise might be the result of optimisation of prefrontal resources via continuous exercise dependent hypofrontality. Overall, better designed trials with more sophisticated outcome measures are necessary to test experimentally the extent to which physical activity might be an effective form of intervention to prevent cognitive decline in ageing and neurodegeneration. There is, however, some recent evidence that the regular practice of walking improves cognition in Alzheimer’s disease, while strength training is particularly more effective for improving postural and motor function, and reducing the risk of developing Alzheimer’s disease, since it improves muscle mass and strength, shown to be affected in this disease., The neuromuscular system is subject to many kinds of damage, from traumatic nerve injury to slowly progressive neuropathies. The emerging field of electroceuticals aims to intervene by recording, processing and normalising neural activity to enhance the function of failing organ systems. Electrical activation has the potential both to maintain muscle mass and to promote neural growth after peripheral neural trauma.1,2 But interaction with the musculoskeletal system must take into account the changes in that system that affect the requirements for artificial activation. The most obvious example is that denervated muscles require much greater current to flow in their membranes to activate release of calcium and contraction than do innervated muscles, whose activation is based on the electrochemical generation of action potentials in the muscle fibre membrane beneath the motor end plates. Similarly, if we are to use stimulation therapy to treat diabetes by neuronal stimulation, then we must take into account that diabetes is often associated with altered neuronal function. The need to inject current from implanted electrodes brings its own risks of tissue damage, tissue heating, and electrolysis of electrode materials. A target denervated muscle may be situated among other innervated muscles, or adjacent to sensory structures. Thus the selection of electrode material, shape and size is important to the outcome. This presentation will review theoretical and practical design criteria to achieve safe and efficient activation of musculoskeletal structures, with some examples.3, Age related changes of the muscle and its adjacent structures also affect the larynx.1 Muscular atrophy leads to an incomplete closure of the vocal folds, leading to a hoarse and breathy voice. The consequences are reduced quality of life and reduced working capacity of persons who are depending on their voices professionally (teachers, policemen etc.). Chronic electrical stimulation of the afferent nerve (recurrent laryngeal nerve) is a completely new therapeutic option that has not been tested before. In a preliminary study we could show that electrical stimulation of the recurrent laryngeal nerve led to an increase of mean muscle fiber diameter in aged sheep, even with a very conservative pattern of two minutes tetanic contraction daily over a period of 29 days.2 Here we present data of an ongoing sheep trial where the electrode was implanted unilaterally adjacent to the terminal branch of the inferior laryngeal nerve. This surgical approach is already close to a clinical setting in humans., The access to different structures in the larynx - especially to the intrinsic muscles in vivo - is limited. Additionally the volumetric quantification is problematic due to their covering with mucosa. Nevertheless it is necessary to generate accurate models of these structures for the purpose of answering muscle-specific issues. Nowadays this is possible with modern imaging procedures such as micro-CT scanning. This technology has advantages over MRI in terms of better resolution and the samples are not destroyed during the imaging process as in histologic sampling. To differentiate the muscles from soft tissue and cartilage, the samples are fixed and preserved in neutral buffered formalin (NBF) and stained with iodine potassium iodide (I2KI) to enhance contrast in the CT-scan.1 The purpose of this study is to generate 3D-models of the laryngeal frameworks and the intrinsic laryngeal muscles by segmentation and finite-element generation using the 3D-analysis-software Avizo®. This modeling technique will be used in ongoing experiments in the field of muscle stimulation for analysis of the results, especially muscle volumes, surfaces and structure. Additionally, phonation experiments on the same subjects were performed to find out correlations between functional parameters and morphometric measurement parameters.2 Phonation analysis included aerodynamic parameters such as the subglottal pressure or the laryngeal flow resistance and acoustic parameters such as the sound pressure level or the fundamental frequencies. Furthermore, high-speed recordings have been performed to visually assess the vocal fold vibrations.3,4, Vocal fold paralysis is a pathological motion impairment of the vocal fold, mostly caused by damage of the N. vagus or the N. laryngeus. If the vocal fold does not reinnervate, paralysis occurs due to denervation of the M. posticus1 Patients with unilateral vocal cord paralysis suffer from hoarseness due to additional atrophy of the M. vocalis with glottal closure insufficiency during phonation. Today’s standard treatment of unilateral paralysis includes surgical medialization through either injection augmentation or laryngeal framework surgery.2 In combination with voice therapy also electrical stimulation of laryngeal muscles has already been used in order to achieve muscle hypertrophy.3 Furthermore research with functional electrical stimulation of patients with long-term denervated limb muscles showed very promising results.4 The selective stimulation of denervated muscles has been investigated in rabbits with unilateral paresis of the recurrent laryngeal nerve. It could be shown that with triangular ramping and very long pulses (> 200ms) afferent and efferent nerve fibers where not reacting at intensity level that already stimulated denervated muscle, with change in muscle fibers confirmed through histology. 5,6 Combining these facts led to the following investigations: Investigating a screening possibility using surface electrodes onto the neck to selectively stimulate the denervated muscle fibers of the vocalis avoiding pain or excitation of sensory nerve fibers or the activation of innervated muscles was the goal of several test stimulations. First results applying long triangular ramping pulses (>200ms) using surface electrodes are surprising. The position and size of electrodes used in the trials were improved continuously. Success could be reported only in the non-awake patient, whereas reasons have to be identified., Facial nerve paralysis as a peripheral nerve injury results in neuromuscular atrophy or in a combination of muscle atrophy and false reinnervation of facial muscles. The symptoms include significant aesthetic, functional and often life-altering consequences. Several procedures such as nerve grafting, facial reanimation by muscle transfer and rehabilitation physiotherapy have been developed to treat functional and cosmetic aspects of this disease.1 Nerve grafting is a sophisticated surgery, that requires experience but offers promising results. Although cable grafting is state of the art, the method suffers the disadvantage of long nerve regrowth time.2 Facial pacing systems show promising results to treat facial paralysis.3,4Former research showed good results stimulating denervated extremity muscles using functional electrical stimulation (FES).5 Nevertheless this field of research has been neglected so far for facial muscles and is lacking optimal stimulation settings to selectively recruit denervated atrophic or simply age-related atrophic facial muscles under non painful conditions. To analyze first optimal FES setting will be the prerequisite to establish FES as a screening tool to select patients for facial pacing. Several ES devices were considered to investigate optimal stimulation settings in patients with chronic facial palsy. To encourage noninvasive screening methods for facial pacing, surface electrodes were used to estimate the optimal settings for stimulations. The use of surface electrodes need for optimized electrode positioning, which was also investigated. Martin et al.6 showed that recruitment of denervated muscles requires exponentially shaped pulses with long phase durations (>200ms). The outcome of our investigation confirmed these findings as well, showing best performance when recruiting paralyzed facial human muscles with biphasic long-duration impulses. It is crucial to position the surface electrodes appropriately in order to avoid stimulation of neighboring muscles not affected by facial palsy, for instance the masseter muscle. Surface electrodes, combined with the optimal stimulation settings, offer a screening possibility for facial pacing but also a therapeutic option to prevent atrophy. Since muscles affected by age-related atrophy could be recruited too, further research is necessary to show effectiveness of training using the determined exponential patterns., Recent studies have correlated physical activity with a better prognosis in cachectic patients, although the underlying mechanisms are not yet understood. In addition, diets enriched with n-3 polyunsaturated fatty acids (n-3 PUFAs) have been shown to exert a positive effect on diseased muscle. Muscle diseases as different as cachexia and dystrophy are characterized but reduced or absence of dystrophin expression, latent or overt muscle damage and impaired regeneration, thus sharing several patophysiological features, such as muscle wasting, loss of muscle mass and function. With the aim to test in preclinical models and in human patients the efficacy of physical, pharmacological and nutritional interventions against muscle wasting and disease, we exploited two different rodent models of cachexia and muscular dystrophy and validated part of these findings in human patients. Part 1. Cancer cachexia. Since we previously found that satellite cells (SC) impairment, due to Pax7 over-expression, contributes to cachexia,1 we studied the effects of voluntary exercise on these cell in colon carcinoma (C26)-bearing mice. We found that endurance exercise rescues Pax7 expression to physiological levels, suggesting that this could be a mechanism underlying its beneficial effects in this condition.2 Moderate exercise training protocols induced muscle adaptation in both control and C26-bearing mice, which are mediated by PPARgamma in a Hsp60-dependent way.3 Indeed, voluntary exercise prevented loss of muscle mass and function, ultimately increasing survival of C26-bearing mice. We found that the exercise mimetic AICAR, rapamycin and exercise equally affect the autophagic system and counteract cachexia.4 We believe autophagy-triggering drugs may be exploited to treat cachexia, especially in conditions in which exercise cannot be prescribed, since cancer patients show abnormal expression of autophagy markers, suggesting that the autophagic flux is blocked in cachexia, thus contributing to muscle wasting. Part 2. Muscle dystrophy. Since flaxseed is one of the richest sources of the n-3 PUFA acid α-linolenic acid (ALA), we assessed the effects of flaxseed and ALA in models of skeletal muscle degeneration characterized by high levels of Tumor Necrosis Factor-α (TNF) and exhaustion of SC myogenic potential. Our study was carried out on dystrophic hamsters and differentiating C2C12 myoblasts treated with TNF, both in the absence or presence of flaxseed diet or ALA treatment, respectively.5 The flaxseed-enriched diet protected the dystrophic muscle from apoptosis and preserved muscle myogenesis both in vivo and in vitro, indicating that flaxseed may exert potent beneficial effects by preserving skeletal muscle regeneration and homeostasis partly through an ALA-mediated action. In conclusion, physical activity, pharmacological treatment (exercise mimetics such as AICAR) and nutritional supplementation (such as ALA) are beneficial for muscle mass preservation and life span increase in the presence of cancer cachexia or muscle dystrophy and should be considered when planning multimodal therapies for muscle diseases., Cachexia is a multifactorial syndrome characterized by body weight loss, muscle wasting, and metabolic abnormalities, that occurs in 50 to 80% of cancer patients and is considered as a predictor of reduced survival accounting for more than 20% of cancer-related deaths.1 Cachexia was defined also as an energy-wasting syndrome, in which mitochondria play a central role as the main energy source. Indeed, mitochondrial alterations and an upregulation of mitophagy markers have been found in the skeletal muscle of cachectic animals.2 In addition to the effects exerted by the tumor, also anti-cancer treatment may contribute to muscle wasting.3 Some years ago, exercise has been proposed as a therapeutic tool to counteract cachexia and the related metabolic alterations,4 including autophagy dysregulation, mitochondrial dysfunction and oxidative capacity reduction.2,5 The present study aimed at evaluating the effects of moderate exercise training on muscle wasting in C26-bearing mice treated with chemotherapy (oxaliplatin+5-fluorouracil; OXFU), focusing on both alterations of muscle autophagy/mitophagy and mitochondrial function. OXFU administration was able to extend the lifespan of the C26-bearing mice (100% survival at 28 days after tumor implantation), but also resulted in exacerbated cachexia. In C26 OXFU mice, exercise partially protected from muscle mass loss and associated with an improvement of muscle function. Chemotherapy further dysregulated cancer-induced autophagy, increasing the levels of Beclin-1 and LC3I. Exercised C26 OXFU mice showed a lower content of Beclin-1 and of both LC3B isoforms compared to sedentary mice. Focusing on mitochondria, the levels of cytochrome c, used as a measure of mitochondrial content, decreased in sedentary C26 OXFU mice, associated with a reduction of SDH protein levels and enzymatic activity. Sedentary C26 OXFU mice showed also increased levels of Bnip-3 and PINK-1, two proteins involved in mitophagy. In C26 OXFU mice, exercise increased the levels of cytochrome c, PGC1α and both SDH content and activity, decreasing also the levels of PINK-1. The alterations seen in C26 OXFU animals were associated with a strong reduction in protein synthesis, that was not improved by exercise. In conclusion, chemotherapy exacerbated tumor-associated muscle wasting and metabolic alterations. Moderate exercise training was able to partially counteract muscle loss and recover muscle function, increasing mitochondrial content, autophagy and damaged-mitochondria clearance, and rescuing muscle oxidative capacity. Therefore, exercise exerts beneficial effects potentially exploitable in the management of cancer patients receiving chemotherapy., Neutral Lipid Storage Disease with Myopathy (NLSDM) is a very rare disorder characterized by a defect in the degradation of cytoplasmic neutral lipids and their accumulation in the lipid droplets (LDs). This neutral lipid metabolism deficiency is associated with mutations of PNPLA2 gene, which encodes adipose triglyceride lipase (ATGL).1-2 ATGL leads to the breakdown of triacylglycerols (TAGs), releasing free fatty acids. NLSDM patients may develop progressive myopathy (100%), cardiomyopathy (44%), diabetes (24%), hepatomegaly (20%), chronic pancreatitis (14%) and short stature (15%). No specific therapy is available today.3-4 Fibroblasts cell lines from two patients and one healthy subject have been reprogrammed into induced pluripotent stem cells (iPSCs). iPSCs are a new technology which can provide an unlimited number of human disease-affected stem cells from different somatic cell lines.5 The first NLSDM patient was homozygous for the c.541_542delAC PNPLA2 mutation that causes the production of a truncated protein lacking the LD-binding domain.3 The second patient was homozygous for the c.662G>C PNPLA2 mutation, determining the p.R221P amino-acid change; this mutation leads to the production of ATGL protein with decreased lipase activity, but able to bind to LDs.2 After about 4 weeks from the Senday infection, karyogram showed a normal karyotype of controls and NLSDM-iPSCs; moreover genomic sequencing analysis confirmed that NLSDM-iPSC lines still contained the disease-specific mutations of PNPLA2 gene. We tested the pluripotency properties of NLSDM-iPSCs evaluating the expression of TRA-1-81, SSEA4 and OCT4 by immunostaining and of SOX2, NANOG, ZFP42, OCT4, hTERT, LIN28, DPPA2 and TDGF1 by qRT-PCR analysis. NLSDM-iPSCs were also able to differentiate into three-germ layers, as revealed by β-III tubulin (ectoderm), α-smooth muscle actin (mesoderm), and FOXA2 (endoderm) expression. Finally, we demonstrated that NLSDM-iPSCs showed an higher storage of TAGs in comparison with control iPSCs, exactly as it could be observed in NLSDM original fibroblasts when compared with control fibroblasts. Indeed, after 3 days in culture, cells were stained with Nile Red and the LD number and dimension were analysed by immunofluorescence analysis; compared to control cells, the NLSDM-iPSCs had 20 times more LDs and almost 5 larger LDs, similar to fibroblasts obtained from the patients. Moreover, oleic acid pulse-chase experiments were performed to confirm that lipase activity was impaired in NLSDM-iPSCs compared to control cells. Collectively, data from this study consistently show that NLSDM-iPSCs recapitulate the disease phenotype of interest. The perspective to differentiate iPSCs into striatum/cardiac muscle lineages will allow us to define a disease model to investigate the pathogenetic mechanisms and to evaluate specific approaches for new pharmacological treatments., How does one choose a pattern of electrical stimulation for therapeutic effect? Often there is a useful guide from normal physiology, and many therapeutic strategies try to mimic or replace a natural activation pattern. Another strategy is to try to generate a numerical model of the excitable tissue to be stimulated so that trials can be achieved in silico.1 Many optimised activation strategies are based on such simulations. We have tested some of the conclusions of studies that have investigated the charge efficiency of activation.2-7 We have used the simple experimental model of a single motor nerve trunk activated by two electrodes placed near to the nerve (common peroneal in rats). The degree of activation has been monitored indirectly by measuring the isometric force of the edl muscle because it has discrete proximal and distal tendons and can thus be mechanically isolated between a proximal clamp and a distal load sensor. We are in a process of critically analysing this data because some of our initial results appeared surprising. We will present results that compare the actual electrode current against the anticipated current based on the use of a voltage-to-current converter. We will also present further analysis of the linearization method that we used to select optimal parameters for the various pulse shapes that we tested. We find that the opportunities to improve energy efficiency are more relevant to monopolar stimulation with one remote electrode far from the nerve than to bipolar stimulation, in which the current field is created between two electrodes both near to the nerve. Such fine differences are important when designing low energy implanted stimulators such as may be used in retinal stimulation or brain stimulation or activation of fine autonomic nerves., In the development of implantable prosthetic devices, much effort has been put into finding optimal anatomical targets for different nerve stimulation techniques. Little work however, has been done to improve the efficiency of nerve stimulation by using analytically driven designs and configurations of the stimulating electrodes. Namely, an electrode geometry can affect the effective impedance, spatial distribution of the electric field in tissue, and consequently the pattern of neural excitation. One approach to enhance the efficiency of neural stimulation is to increase the irregularity of the surface current profile. In this relation, it has been shown, that adequately optimized electrode geometries and surfaces that increase the variation of current density on the electrode surface enable also an increase of the efficiency of neural stimulation. In this relation, a variety of mechanical adaptations, such as geometry and surface roughness of the electrodes, have been investigated and implemented. The purpose of the study was therefore to assess "in vitro" the electrochemical performance of two stimulating electrodes (WEs) with different surface structures obtained by treating the surface with smooth and rough sand paper. To craft the stimulating electrodes, 0.03-mm-thick cold-rolled platinum foil strips with 99.99 wt.% purity and dynamic annealing in an argon atmosphere were used. The obtained final dimensions of the electrodes exposed to the physiological solution were: width 0.66 mm, length 3 mm and surface area 2 mm2. For adaptations of two investigated WEs via increase their real surface, two differently grained sand papers (Waterproof Silica Carbide Paper FEPA P#500 and FEPA 4000, Struers ApS, Pederstrupvej 84, 2750 Ballerup, Denmark) were used. A surface of the WE1 was enlarged using rough sand paper FEPA P#500 while WE2 was enlarged using fine-grained sand paper FEPA P#4000. For the purpose of spot welding of the stainless-steel wire and the platinum foil, a custom-designed, capacitive-discharge, research-spot-welding device, providing a standard single pulse, was developed. The welding energy for both electrodes is defined experimentally. To analyse any failure and to reveal the microstructure of the weld, and consequently to set up optimum welding conditions, scanning electron microscopy was used. The results provide evidence that the welds between the stainless-steel wire and the platinum foil do not show any typical welding defects, such as oxide films, oxide inclusions, gas bubbles or shrinkage porosity. Obtained results also show that an impedance of WE1 is lower than impedance of WE2. Accordingly, the WE1 is more suitable for safe stimulation than WE2., Transcutaneous spinal cord stimulation (tSCS) has been shown to abbreviate spasticity in lower limbs in people with incomplete spinal cord injury (SCI) people.1,2 Therefore tSCS is a therapy of choice for SCI in our clinic. It is also known that SCI modulates the organisation of the brain in the way that it decreases the areas allocated for the control of the not connected extremity part.3 Therefore we hypothesize that the tSCS treatment can influence the plasticity of the brain as well. In this work the footprint of the tSCS in the EEG is sought in order to verify that the stimulating signals are transmitted to the brain. In this first approach one healthy subject for control and one Cerebral palsy (CP) patient participated. Cortical somatosensory evoked potentials (SEP) where recorded during tibial nerve stimulation and during tSCS. The recording of SEP during tibial nerve is well documented so it serves as a proof of method. Then SEP was also recorded during voluntary ankle dorsiflexion and analyzed for event-related (de-)synchronization (ERD/ERS).4 SEP is clearly to be seen in the sensorimotor cortex during tSCS. It is though different in form from the SEP during tibial nerve stimulation. As expected the ERD/ERS were focused over the Cz electrode as documented in the literature.4 After movement by the CP subject the synchronisation was limited and therefore different to a healthy subject. But no significant changes where found after treatment. As the tSCS modifies the SEP the hypothesis that the treatment could influence the brains plasticity is supported. The difference in SEP between tSCS and tibial nerve stimulation suggests that different fibres in the spinal cord are stimulated. ERD/ERS patterns are changed in CP compared to a healthy subject., Aging of the human skeletal muscles results from decline of both muscles strength and power.1 The athletic world records of the Master athletes at ages ranging between 35 to 100 years are an excellent proof of such decline in all competitions. The world record performances can be transformed into dimensionless parameters proportional to the power developed in the trials. Such parameters range from 1 for the Senior world record (i.e. the maximum human performance) through medium values for the Master athletes to reach 0 for a null performance.1 Therefore, the decline of the power parameter with relation to human aging can be analysed and compared as follow: the trend-lines start to decline very close to the age of 30 years and arrive to 0 around the age of 110 years for each athletic discipline. There are no reasons, for each one of us, to decline differently from the world record-men, provided that each of us remains in a stable fitness condition without disabling pathologies. On the other hand, the methods to evaluate decline in the older olds need to be adapted to the extent of decay (as it is very commonly done in pathology). This is particularly important after 70 years of age and according to sex difference in power. We have adapted clinical methods,2,3 to evaluate dexterity and mobility in normal older olds introducing 5 simplified Tests. Patients are assessed with the Timed Up and Go Test (TUGT), Five Chair Rise Test (5xCRT), and Jug Test (JT).3,4 The Timed Up and Go Test has been validated as a useful indicator of leg muscle performance in numerous populations, including patients with neuromuscular diseases. Additionally, maximal isometric torque of quadriceps muscle on a force measurement chair is determined as [Nm/s] and the time which a subject needs to rise from a chair with arms folded across the chest 5 times (i.e., Five Chair Rise Test, 5xCRT) is measured.3 The “jug test” (floor-to-table jug test, JT) provides information on the behaviour of arm, shoulder and trunk muscles. Specifically, participants move five 1-gallon jugs (≈3.9 kg) from the floor to a normal 75 cm high table level - as quickly as possible.4 This action is quite like the everyday activity of lifting a shopping bag from ground to table. The weight of the jug varies according to age and gender of subjects as indicated in the following template of Functional Test Report. Further, every day mobility is assessed by providing a pedometer (Nakosite, USA). The participants hold it 24 hours a day, for two weeks with break periods of three months. All functional results are correlated to 3D false color computed tomography of skeletal muscles.5, MicroRNAs (miRNAs) are small non-coding RNAs that have been shown to modulate a wide range of biological functions under various pathophysiological conditions. miRNAs are 17-27 nucleotides long molecules that regulate post-transcriptional mRNA expression, typically by binding to the 3’-untranslated region of the complementary mRNA sequence, and resulting in translational repression and gene silencing. Therefore, an increase in a specific miRNA results in a decreased expression of the corresponding protein product. Several studies have shown that there are thousands of different human miRNA sequences that control the expression of 20-30% of protein-coding genes, indicating that miRNAs are “master regulators” of many important biological processes. MiRNAs are known to be secreted by various cell types and, unlike most mRNAs, they are markedly stable in circulating body fluids due to proteic protection from ribonucleases. Because of these properties, miRNAs have recently gained attention for their potential as minimally invasive and cost-effective disease biomarkers. Because of their stability in plasma and serum, they can be reliably detected even at low concentration and used not only as markers of disease, but also of disease staging, and possibly to quantitatively measure the effectiveness of novel drug therapies. These miRNAs (miR-206, miR-133a, miR-133b, miR-1) are called “myo-miRNA” and are considered as markers of muscle regeneration, myogenesis, fiber type differentiation, degeneration, injury and might represent indicators of residual muscle mass consequent to a chronic atrophy of muscle. Myo-miRNAs are variably expressed in several muscle processes, including myogenesis, and muscle regeneration.1-3 We explored their function beside in several conditions with severe muscular atrophy, including Amyotrophic Lateral Sclerosis (ALS). ALS is a rare, progressive, neurodegenerative disorder caused by degeneration of upper and lower motoneurons. The effects of exercise and rehabilitation in patients with ALS are still debated. A moderate and regular exercise is supported in the treatment of many neuromuscular diseases. We previously conducted microRNAs studies in ALS patients and we observed differences in myomiRNAs levels in spinal versus bulbar onset (4). In this study we analysed the role of circulating myomiRNAs after physical rehabilitation. We measured muscle specific microRNAs (miR-1,miR-206,miR-133a,miR-133b) by Real Time PCR in 19 ALS patients (12 male,7 female). We analysed the levels of these microRNAs in serum collected before (T0) and after (T1) a period of 6-8 weeks of rehabilitation. We observed a general down-regulation of all miRNAs studied after rehabilitation. In our population myomiRNAs decreased in a similar manner in male and female patients, therefore no gender effect was found. On the contrary the age of patients under study was found to be relevant: patients under 55 years old have a more marked decrease in myomiRNAs levels than patients with older age. We have found that microRNAs are an important tool to monitor rehabilitation in ALS patients and suggests a positive effect of the treatment. There seems to be a more pronounced decrease in myomiRNA levels in patients with younger age in this motoneuron disease after physical rehabilitation. Further studies are needed to correlate circulating microRNAs with muscle atrophy and to confirm age differences., Within a study which eventually demonstrated the efficacy of peri-patellar injections of high molecular weight Hyaluronic Acid (HA) in the maintenance of the tendon structure during detraining in the rats1,2, a transcriptomic study using Next Generation Sequencing was carried out in rat hearts in order to evaluate training-and detraining-associated adaptations in gene expression. While the comparison between trained and untrained hearts yielded 593 differentially expressed (p≤0.05) genes, as many as 762 genes were found to be differentially expressed in the comparison between the hearts of detrained rats receiving either HA or saline peri-patellar injections. Differentially expressed genes were assigned to functional categories and to KEGG pathways by using the FatiGO software. By and large, gene expression analysis suggested that HA injections at a distant site appear to support the ability of the heart to repair injuries and to enforce differentiative pathways. HA has a well-known role in cardiac differentiation, by activating the ERK 1/2 and pathways3 and modulating the WNT/β-catenin and Smad signaling.4,5 The experimental use of HA in in vivo recovery from ischemia/reperfusion injuries has been so far limited to animal studies, owing to the concept that, in order to be effective, HA-containing hydrogels should be applied on the site of injury, a very delicate and potentially harmful procedure. Should the present transcriptomic study be validated by ongoing proteomic studies, these serendipitous results may pave the way for the validation of HA administration at distant sites and even orally, in the therapy of infarcted patients and even in the prevention of cardiovascular diseases in subjects at risk and in the elderly. This work has been partly supported by a grant awarded by FIDIA, Friedreich’s Ataxia (FRDA, OMIM #229300) is a severe neurodegenerative disease due to an autosomal recessive mutation and characterized by progressive impairment of voluntary movements. In most patients, FRDA is associated with hypertrophic dilated cardiomyopathy, which is the more frequent cause of death. The underlying mutation in FRDA causes a marked reduction of a small protein, frataxin, which is involved in iron handling, mostly, but not exclusively, in mitochondria; its main role is the assistance in the formation of iron-sulphur containing protein complexes. Patients affected by FRDA show iron inclusions in cardiomyocytes and iron aggregates in the cardiac tissue1. We therefore devised to study the iron homeostasis in iPSC-derived cardiomyocytes obtained from a patient affected by FRDA, which were compared to iPSC-derived cardiomyocytes obtained from a healthy subject. Induced Pluripotent Stem Cells were obtained from skin fibroblasts according to the Yamanaka procedure, differentiated following the GiWi protocol2, and thoroughly characterized. The gene expression of Hepcidin, Ferroportin, Transferrin Receptor 1 and Ferritin was studied in basal conditions; their change following an iron load is the object of a study presently being carried out in our lab. Messenger RNA levels for Hepcidin were found to be increased in cardiomyocytes from the FRDA patient, while the amounts of Ferroportin and Transferrin Receptor 1 mRNAs were decreased with respect to cardiomyocytes from a control subject. These data will be discussed in the light of the role played by the proteins coded by the above mentioned genes in iron homeostasis and of their expression in different experimental models. This work has been partly supported by AISA ONLUS (Associazione Italiana per le Sinromi Atassiche), All progressive muscle contractile impairments need permanent managements, including aging-related muscle-strength decline . Frail elderly persons due to advanced age or associated diseases are often hospitalized for long periods of time. There, their already modest amount of daily physical activity is reduced, contributing to limit their independence up to force them to the bed. Immobility is associated with neuromuscular weakness, functional limitations, thromboembolism and high costs.1-3 Beside the eventual pharmacology therapy, a home-based physical exercise approach is helpful. Awaiting development of electroceuticals, as effective as pace-makers or cochlear implants, education of hospitalized patients to take-home physical exercise managements is an effective low cost alternative. Inspired by the proven capability to recover skeletal muscle strength by home-based Functional Electrical Stimulation even in the worse cases of neuromuscular traumatic injuries,3-4 but, guided by common sense, we suggest a brief (15-20 minutes) daily routine of twelve easy-to-be-done physical exercises that are performed in bed (Full-body In-Bed Gym).5 Full-body Inbed Gym is an extension to all body muscles of well-established physiotherapy approaches of in-bed cardio-circulation-ventilation workouts. If sedentary borderline persons challenge, without stress, them-self, in hospital Full-body In-Bed Gym may increase muscle strength, fatigue resistance and independence in daily life activities. In surgical units this will grant standing of patients soon after operation, a mandatory measure to prevent risk of thromboembolism. Full-body In-Bed Gym helps also to mitigate the bad mood that accompanies mobility limitations, strengthening patients’ confidence in recovering partial or total independence. Full-body In-Bed Gym may also mitigate eventual arterial hypertension, a major risk factor in elderly persons. Continued regularly, Full-body In-Bed Gym may help to maintain the independence of frail older people and to reduce the risks of the possible serious consequences of accidental falls. Simplified Functional Tests may be used to follow-up the suggested approaches. Take home messages: It is never too early, it is never too late to start anti-aging Full-body In-Bed Gym and FES to help older olds and change lazy, depressed person into active seniors. There are no needs of personal trainers or demanding devices. Secure to your self, please, a better life-style watching the video of Full-body In-Bed Gym.5 http://www.bio.unipd.it/bam/video/InterviewCarraro-tutorial.mp4, MicroRNAs are small non coding RNAs that are associated to stress granules, mitochondria and other subcellular organelles in muscle. Few studies have explored microRNAs role in muscle atrophy in Amyotrophic lateral sclerosis(ALS). We previously observed that there is different serum microRNA profile in spinal versus bulbar ALS. We have investigated muscle biopsies in a series of ALS cases both sporadic and genetic. We studied, in EI Escorial proven ALS cases muscle biopsies obtained for diagnostic reasons, myomicroRNAs (MiR-1;MiR-206; MiR-133a; MiR-133b; MiR-27a) and inflammatory microRNAs (MiR-155; MiR-146a; MiR-221; MiR-149*) by qRT-PCR.ALS cases were divided according to gender and age of onset. Atrophy factors were calculated in muscle fibers according to Dubowitz. Two cases had mutation of SOD and c9orf. Morphometric analysis of muscle fiber size was done to correlate muscle atrophy with molecular parameters. All microRNAs studied were strongly up-regulated in muscle biopsies of ALS patients versus controls with the exception of miR-149*. Significant overexpression of miRNAs was present in genetic versus sporadic and in male versus female gender. Morphometric analysis confirmed a muscle fibre atrophy in ALS patients compared to controls. Two genetic ALS (SOD, C9ORF) were atrophic with high fiber CSA variability in agreement with the up-regulation we found of myomiRNAs that directly correlates with the degree of atrophy. In conclusion, these results provide evidence on molecular role of microRNAs in correlation to muscle atrophy. In addiction we observed an increased expression of microRNAs in genetic ALS and dysregulation of inflammatory microRNA., We report muscle histopathological, ultrastructural and radiological features of a large Italian-Spanish family with autosomal dominant LGMD, previously mapped to 7q32.2-32.2 (LGMD1F). We collected the DNA, clinical history, muscle biopsies histopathology of one LGMD1F kindship. Biopsy of two affected patients mother and daughter was studied (in the daughter two consecutive biopsies at 9 and 28 years and in the mother at 48 years). In LGMD1F patients the age of onset varied from 2 to 35 years, weakness occurred either in upper or in lower girdle; in 14 cases there was hypotropy both in proximal upper and lower extremities in calf muscles. Muscles MRI showed hyperintensity in proximal limb muscles. The daughter has a severe clinical course and the fiber atrophy was more prominent in the second biopsy at 28 years. The mother has a relatively compromised histopathology and many small muscle fibers, and autophagic changes by acid-phosphates stain. Immunofluorescence against desmin, myotilin, p62 and LC3 showed accumulation of myofibrils, ubiquitin binding proteins aggregates and autophagosomes. Ultrastructural analysis revealed myofibrillar disarray, vacuolar changes, granular material and dense subsarcolemmal bodies deriving from cytoskeleton-myofibrillar proteins. We hypotize that the pathogenetic mechanism in LGMD1F might lead to disarrangement of desmin-associated cytoskeletal network. Transportin-3 (TPNO3), which was found by NGS to be the causative gene in LGMD1F, is suggested to mediate the nuclear inport-export. The non-stop mutation identified in this family encodes for a longer protein which is expected to be unable to move to the nucleus. Clinical phenotype penetrance in this family correlates at 92% with mutation presence. MRI imaging is a powerful tool for the follow up in the evolution of this dominant LGMD and demonstrated atrophy of lower girdle., Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is a master regulator of mitochondrial biogenesis. In skeletal muscle, PGC-1α expression is induced by exercise.1 Along this line, mice overexpressing PGC-1α specifically in the skeletal muscle are characterized by enhanced exercise performance in comparison with wild-type animals; this is mainly due to increased myofiber mitochondrial content that results in markedly improved energy metabolism. In addition to an increased proportion of oxidative fibers vs glycolytic ones,2 the histological analysis of muscle overexpressing PGC-1α revealed a high number of fibers with centrally located nuclei, which is indicative of muscle regeneration. Starting from this unexpected observation, the aim of the study was to investigate the effects on myogenesis exerted by PGC-1α overexpression. Myogenic stem cells are more abundant in transgenic mice compared to wild-type animals. When cultured in differentiating medium, cells isolated from PGC-1α mice form myotubes larger than those generated by cells derived from wild-type animals. To understand if such improved in vitro myogenic capacity also occurs in vivo, both wild-type and PGC-1α transgenic mice received an intramuscular injection of BaCl2 in order to induce muscle regeneration. While 14 days after muscle injury myofiber cross sectional area was not different in wild-type and transgenic mice, at day 8 from BaCl2injection the number of central nuclei was higher in the latter than in the former. On the whole, these results suggest that overexpression of PGC-1α might favor both myogenic differentiation and regeneration when mild damage occurs, such as during exercise, but it is not able to accelerate muscle recovery when acute damage is inflicted, despite the high propension to myogenesis shown in vitro., Skeletal muscle atrophy is the loss of muscle size and strength which occurs with neural and skeletal muscle injuries, prolonged bed rest, space flight, normal aging, and diseases such as sepsis cachexia, diabetes, etc. If unabated, skeletal muscle atrophy can be extremely debilitating, increasing mortality and morbidity in affected people. Current strategies for diagnosis and evaluation of skeletal muscle are not adequate to evaluate fully the condition of this tissue. Thus, proper diagnosis and treatment are often delayed, resulting in unnecessary human discomfort and down time. Quantitative Muscle Color Computed Tomography (QMC-CT) is a highly sensitive quantitative imaging analysis recently introduced by our group to monitor skeletal muscle condition. Despite its powerful potential, this technique is not widely known. Therefore, the objective of this project is to validate QMC-CT as a superior Muscle Imaging technique for evaluating skeletal muscle. This project addresses the “Barriers to Successful Therapy Outcomes” option within the Rehabilitation Focus Area of the DOD Peer Reviewed Orthopaedic Research Program because it will explore the sensitivity of QMC-CT and thus validate its use as an improved method for monitoring skeletal muscle health and recovery. Validation of QMC-CT will provide physicians an improved tool to quantitate skeletal muscle before and during rehabilitation so that therapy for mobility-impaired persons can be better prescribed, evaluated and altered where needed. Benefit to Military Service Members and Veterans: A recent report from the U.S. Army describes injuries as an “epidemic” which has become the “number one health threat” to the U.S. military.1 This document reports that the majority of injuries occurring at Army garrisons were musculoskeletal injuries to the ankle, knee, lower back or shoulders. Further, it has been reported that non-combat injuries have resulted in more medical air evacuations from Iraq and Afghanistan than combat injuries.2 These injuries result in physical discomfort and potential mental duress in addition to some degree of personnel down time. The more serious injuries can result in life long issues. QMC-CT will provide medical personnel with a superior technique for imaging skeletal muscle and surrounding tissues. In the short term, the use of QMC-CT will enhance the speed and accuracy of patient evaluation, thus improving diagnosis, treatment and patient morale. In the long term, the improved initial treatments will reduce patient treatment time, personnel down time and enduring negative injury-related issues. Because the technology has the potential to improve medical treatment in both military and non-military facilities, the method has the potential to improve health care for soldiers, veterans and the population at large., The most severe forms of muscular dystrophies (MD) occur due to mutations in the components of the dystrophin-glycoprotein complex (DGC), a molecular scaffold which is localized to sarcolemma and provides mechanical stability to striated muscle. Studies have shown that loss of DGC proteins results in the activation of several pathological cascades1. Dystrophic muscle is characterized by chronic inflammation, fibrosis and progressive myofiber loss. No effective treatment is currently able to counteract MD pathological cascades. Plant-derived nutritional compounds exhibit ability to modulate several pathological pathways in various degenerative diseases2. Our studies have been demonstrated that a Plant-based diet enriched of flaxseed (FS-diet), is able to stimulate multiple protective and regenerative mechanisms on skeletal muscles of dystrophic hamster, affected by a deletion in the δ-sarcoglycan gene. The FS-diet modulates lipid membrane composition preserving expression of key-role signaling proteins, such as caveolin-3, α-dystroglycan, and sarcoglycans, therefore repairing the sarcolemma damage, which is the primary consequence of gene mutation. The FS-diet prevents inflammation, fibrosis and skeletal muscle degeneration in dystrophic hamster, extending the animals’ lifespan3. The mechanisms involved include modulation of various pathways such as the TNF, PI3K/Akt, TGF-β, and Bax/Bcl-2 signaling pathways. Because flaxseed is one of the richest sources of omega-3 fatty acid, a-linolenic acid (ALA) a further step of “in vitro” experiments were performed on ALA-treated differentiating myoblasts3,4. ALA prevents the TNF-induced inhibition of myogenesis and reduces apoptosis in C2C12 cells by regulating key proteins involved in balancing survival/death in skeletal muscle such as caveolin-3, caspase-3 and Bcl-2. These findings indicate that flaxseed may exert pleiotropic beneficial effects on the dystrophic skeletal muscle partly through an ALA-mediated action. As a nutraceutical that exerts multifaceted effects, the omega-3 fatty acid ALA, as well as others compounds contained in flaxseed, should be clinically developed further for use in the prevention and treatment of the muscular dystrophies., Understanding the underlying mechanisms involved in maintenance, increase and loss of muscle mass remains an interesting and challenging field with potential applications not only in bodybuilding, but also with respect to counteract the decline in muscular function caused by disease or ageing. Muscular activity and loading are essential parameters controlling the equilibrium between protein synthesis and degradation. Various animal models have been used in the past to investigate hypertrophy in rodents by increasing the average loading of particular muscles.1-9 Some models demonstrated the effect of compensatory hypertrophy by removal or denervation of antagonists producing a constant overload.1-3 Others established training modalities including squats,3 weight lifting,4,5 jumping for a food reward, and treadmill or ladder climbing,6 sometimes with added weights,7 to increase the muscular effort. Our recent study tests the effect of programmed resistance training of the tibialis anterior (TA) muscle by means of electrical stimulation, on muscular hypertrophy. In the rat hind limb, the dorsiflexor muscles that lift the foot are supplied by the common peroneal nerve (CPN) whereas the plantarflexor muscles are supplied by the tibial nerve. In preliminary force measurements we investigated the loading experienced by the TA muscle for unloaded concentric contractions and isometric contractions for the fully recruited CPN. Further measurements were performed in which part of the antagonistic plantarflexors was simultaneously activated with the fully recruited TA muscle. This was achieved with a single channel pulse generator by placing the cathode under the CPN and the anode under the tibial nerve, further referred to as “SpillOver” stimulation of the plantarflexors, because the amount of activation of the tibial nerve can be controlled by adjusting stimulus amplitude above the level that produces supramaximal activation of the CPN. The results of these force measurements suggest that unloaded contractions, even with full activation of the CPN might not provide a sufficient stimulus to induce muscular hypertrophy. To test this hypothesis we performed experimental trials on 10 animals comparing the hypertrophic response of unloaded concentrations elicited by stimulation of the CPN (n=5) versus antagonistic co-contraction using the proposed SpillOver stimulation (n=5). A stimulation pattern of one session per day consisting of 5 sets of 10 repetitions at 100Hz (2s ON 2s OFF) and 2.5 minutes between sets, was applied for a duration of 4 weeks by small implantable pulse generators (MiniVStim 12B, Center of Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria). After the experiments the TA muscles were harvested, weighed and snap-frozen for further histometric analysis. The wet weight of the TA muscle showed an increase of +5.4 % ± 2.5 % (MEAN ± SEM) for unloaded contractions while antagonistic co-contraction revealed an increase +13.9 % ± 1.3 %. The average differences of the median fibre cross-sectional-area were +12.8 % ± 6.4 % and +33.3 % ± 16.5 % for unloaded contractions and co-contractions, respectively. We will use this model to investigate further the sensitivity to hypertrophy of the various fibre types and the cellular pathways that are activated in this response.

Physical exercise is known to have beneficial effects on muscle trophism and force production modulating signaling pathways involved in fiber type plasticity, muscle growth and mitochondria respiratory efficiency.1 It has been shown that the decrease of muscle mass and strength observed in aging is linked to intracellular and extracellular abnormalities, that is, sarcoplasmic reticulum-to-mitochondria malfunctions and extracellular matrix metabolism, respectively. Lifelong, high-level physical activity delays the medium and long term effects of aging. Furthermore, when healthy seniors are exposed to regular neuromuscular Functional Electrical Stimulation (FES) training for a period of 9 weeks outcomes are an increase in muscle strength and muscle fiber size and, most importantly, an increase of fast fibers, the more powerful of skeletal muscle motor units. Electron microscopy analysis of aging muscle show remodeling of mitochondrial apparatus as a consequence of fusion phenomena that are consistent with adaptation to physical exercise. Altogether these results indicate that the FES-dependent beneficial effects on muscle force and mass are associated with changes in mitochondrial- and sarcoplasmic reticulum-related proteins involved in Ca2+ homeostasis, providing new targets to develop therapeutic strategies to promote healthy aging., All permanent or progressive muscle contractility impairments (including age-related muscle power decline) need permanent managements. Beside eventual pharmacology therapy, a home-based physical exercise approach is helpful, in particular for bed-rested or bed-ridden patients. Awaiting development of implantable devices for muscle stimulation, i.e., of electroceuticals as effective as pace-makers for cardiac arrhythmias or cochlear implants for hearing loss, education of hospitalized patients to take-home physical exercise managements is an effective low cost alternative. Frail elderly due to advanced age or associated diseases are often hospitalized for long periods of time. There, their already modest amount of daily physical activity is reduced, contributing to limit their independence up to force them to the bed. Inspired by the proven capability to recover skeletal muscle contractility and strength by home-based Functional Electrical Stimulation (h-bFES) even in the worse cases of neuromuscular traumatic injuries,3-5 but, mainly guided by common sense, we suggest a short (15-20 minutes) daily sequence of fifteen easy volitional physical exercises that are performed in bed (In-Bed Gym). If sedentary borderline persons challenge, but not stress, them-self, in a few days in hospital In-Bed Gym may increase muscle strength, fatigue resistance and independence in daily life activities. In surgical units this will grant standing of patients soon after operation, a mandatory measure to prevent thromboembolism risk. In-Bed Gym helps also to mitigate the bad mood that accompanies mobility limitations, strengthening patients’ confidence in recovering partial or total independence Continued regularly, In-Bed Gym may help to maintain the independence of frail older people and to reduce the risk of the possible serious consequences of accidental falls. In-Bed Gym may also mitigate eventual arterial hypertension, a major risk factor in elderly people.7, Disruption of circadian rhythms in humans and rodents has implicated a fundamental role for circadian rhythms in aging and the development of many chronic diseases including diabetes, cardiovascular disease, depression and cancer. The molecular clock mechanism underlies circadian rhythms and is defined by a transcription-translation feedback loop with Bmal1 encoding a core molecular clock transcription factor. Germline Bmal1 knockout (Bmal1 KO) mice have a shortened lifespan, show features of advanced aging and exhibit significant weakness with decreased maximum specific tension at the whole muscle and single fiber levels.1 We tested the role of the molecular clock in adult skeletal muscle by generating mice that allow for the inducible skeletal muscle-specific deletion of Bmal1 (iMSBmal1),2 Here we show that disruption of the molecular clock, specifically in adult skeletal muscle is associated with a muscle phenotype including reductions in specific tension, increased oxidative fiber type, and increased muscle fibrosis similar to that seen in the Bmal1 KO mouse. Remarkably, the phenotype observed in the iMSBmal1-/- mice was not limited to changes in muscle. Similar to the germline Bmal1 KO mice, we observed significant bone and cartilage changes throughout the body suggesting a role for the skeletal muscle molecular clock in both the skeletal muscle niche and the systemic milieu.3 This emerging area of circadian rhythms and the molecular clock in skeletal muscle holds potential to provide significant insight into intrinsic mechanisms of the maintenance of muscle quality and function as well as identifies a novel crosstalk between skeletal muscle, cartilage and bone., Physical activity and circadian rhythms are well-established determinants of human health and disease, but the relationship between muscle activity and the circadian regulation of muscle genes is a relatively new area of research. We compared the circadian transcriptomes of two mouse hind-limb muscles with vastly different circadian activity patterns, the continuously active slow soleus and the sporadically active fast tibialis anterior, in the presence or absence of a functional skeletal muscle clock (skeletal muscle-specific *Bmal1* KO). In addition, we compared the effect of denervation on muscle circadian gene expression. We found that different skeletal muscles exhibit major differences in their circadian transcriptomes, yet clock gene oscillations were essentially identical in fast and slow muscles. Furthermore, denervation caused relatively minor changes in circadian expression of most clock genes, yet major differences in expression level, phase and amplitude of many muscle circadian genes. Our studies suggest that a major physiological role of the skeletal muscle clock is to prepare the muscle for the transition from the light/inactive/fasting phase to the dark/active/feeding phase, in anticipation of periodic fluctuations in fuel supply and demand., Muscle wasting in intensive care unit (ICU) patients may be related to the primary disease, but there is heterogeneity of underlying disease and pharmacological treatment among patients exhibiting similar outcomes. Thus, it is highly likely that a common component of ICU treatment per se is directly involved in the progressive impairment of muscle function and muscle wasting during long-term ICU treatment. The specific mechanisms underlying the muscle wasting and impaired muscle function associated with the ICU intervention are poorly understood in the clinical setting.1 This is in part due to heterogeneity in pharmacological treatment, underlying disease, clinical history etc. There is, accordingly, compelling need for experimental animal models closely mimicking the ICU condition, including long-term exposure to mechanical ventilation and immobilization (lack of weight bearing and activation of contractile proteins, i.e., “mechanical silencing”). In this project, the muscle dysfunction, which by far exceeds the loss in muscle mass in limb and respiratory muscles in patients with CIM2,3 and VIDD,4 have been investigated in detail at the cellular and molecular levels in a rodent experimental ICU model, allowing detailed studies in an immobilized and a mechanically ventilated rat for long durations (up to weeks-months). The long-term scientific goals of the research are to: (a) define the causative agents, (b) develop sensitive, quick and accurate diagnostic tools and monitoring devices, and (c) develop efficient intervention strategies. This project, which focuses on the mechanisms underlying the severely impaired limb and respiratory muscle function (CIM and VIDD) in response to long-term mechanical ventilation and immobilization and the introduction of specific intervention strategies, constitutes a significant component of the attempt to achieve these long-term goals., The diaphragm is the most important inspiratory muscle. It has a thin, dome-shaped structure, and separates the thoracic and abdominal cavities, mechanically interacting with the surrounding organs during its contractile function. Moreover, its muscle fibers have a complicated geometry, connecting to several ribs, lumbar vertebral bodies and to the central tendon. All these peculiar features make it a very challenging organ to be modeled and analyzed by means of finite element methods. We present our work aimed at creating a finite element model of the human diaphragm. A computational model based on a realistic, potentially patient specific, geometry, may help in the understanding of diaphragm related pathologies, such as chronic obstructive pulmonary disease (COPD), mechanical ventilation (MV) induced diaphragm inactivity, amyotrophic lateral sclerosis (ALS) or even for respiratory tumor motion tracking to reduce radiation treatment side effects. On the other side, several diaphragm pathologies are related to relevant modifications of the single fiber properties, such as contractile weakness, atrophy, or reduced cross sectional area. Moreover different fiber isoforms differently affect the whole muscle behavior. In the design of our model, we adopted a bottom-up approach, trying to explain the whole muscle behavior starting from the single fiber characterization. Therefore, we first developed a model for a single fiber based on a three elements Hill’s model which is able to reproduce the classic protocols for the force velocity curve (isometric contraction followed by an isotonic contraction at different external forces) as well as the slack-test protocols (isometric contraction followed by a rapid shortening imposed to the fiber. We then characterized the parameters for both fast and slow human skeletal fibers, based on the original experimental data obtained in our lab, taking into account the effects of temperatures as single fiber mechanics is generally studied at low temperature (12-20°C). The characteristic width of the elements in the mesh of the diaphragm is several tens of microns, which means that each element likely include several slow and fast fibers. Then a characterization of the mixed fiber bundles is needed. We therefore characterized a mesh describing a bundle of fast and slow fibers to reproduce the mixing effect on the force velocity curve. The transversal connections linking each other adjacent fibers were taken into consideration. The mesh for the bundles was based on histological cross sections of diaphragm, which can be found in the literature [1]. Finally, we included our results in a 3-D mesh representing the human diaphragm. The bottom-up approach based on the real behavior of single bundles of fibers, is particularly useful to predict how different pathologies at the fiber level can influence the whole muscle performance., All skeletal muscles undergo an age-dependent loss of mass and functional deterioration. As follow-up of the functional impairment of lower limb muscles, the elderly experience limitations in locomotion and eventually lose the possibility of independent life. Accordingly, an impairment in respiratory function is the expected effect of the age-dependent decline of respiratory muscles. In spite of its essential role in breathing the age-dependent modifications of diaphragm muscle (DIAm), which is the main inspiratory muscle, have received less attention than limb muscles (Greising et al 2013, Elliott et al 2015). In this study we aimed to investigate the age-related changes of the mouse diaphragm and the possible impact of moderate endurance training. The respiratory function in mice is very different compared to humans. Breathing in mice as in other small mammals is characterized by very high frequency (400-500/min) and low tidal volume (, Denervated left emi-diaphragm of adult rats is well known to paradoxically increase in weight during the first ten days after denervation, then it atrophy as any other denervated muscle.1 Increased activity of eIF-2 initiation factor accounts at least in part for the enhancement of protein synthesis in 2-day denervated emi-diaphragm of adult rats.2 Nothing is known about the behavior of the denervated emi-diaphragm in oldest (30-month) rats. We compared in two groups of four animals (3-month adults vs 30-month oldest male rats) the effect on functional and structural properties of 7-day denervation in the diaphragm and in denervated EDL and Soleus leg muscles. At 30-month the body weight of the rats is high significantly heavier than that of the 3-month animals (gr 289+/-44 vs 401+/-38, mean+/-SD, p< 0.001). Despite the increase in body weight the weight of the innervated EDL, and SOL muscles are lower in the oldest rats. Equal or slightly lower are also sizes of muscle fibers in 30-month innervated EDL, SOL and diaphragm. Contrastingly, the response to 7-day denervation is muscle related: EDL and SOL leg muscles show a 15% decrease in muscle fiber size, while the muscle fiber of denervated left emi-diaphragm are indistinguishable from contralateral innervated muscle in 3-month and 30-month rats. Of note is the fact, that in the 7-day denervated left emi-diaphragm of the oldest rats (30-month) slow-type muscle fiber present a 5.7% highly significantly increase in fiber size, and that in two out of the four rats total muscle fiber size analyzed in semi-thin section after fixation for electron microscopy present highly significant increase (+ 14.5 %) when compared with the contralateral innervated emi-diaphragm. On the other hand, muscle fibers of 7-day denervated EDL and SOL of the same rats show the expected decrease in size (-18.7 %). In conclusion, both young and old diaphragms appear to be unresponsive to 7-day denervation atrophy., Neuromuscular Junction (NMJ) is the synapse that connects motor-neuron with skeletal muscle and its stability is critical for muscle contraction. Inherited or acquired conditions that perturb the components of this unit lead to weakness, denervation and, ultimately, paralysis.1,2 The signals that control such complex/critical structure in adulthood are largely unknown. Here we show that a retrograde signal is released from adult skeletal muscles to maintain a stable and functional NMJ. An efficient autophagy system is required for a functional NMJ because it controls MuSK clustering3 Impairment of autophagy or inhibition of MuSK leads to NMJ dismantle and denervation. These results identify MuSK-autophagy axis as a retrograde signal that is required for NMJ maintenance and function in adulthood., Endolysosomal carriers containing nicotinic acetylcholine receptors (CHRN) are either recycled (1) or degraded via autophagy during atrophic conditions (2, 5). However, regulatory processes underlying their processing have remained elusive. We have recently shown that internalized CHRN are accompanied by TRIM63 (MuRF1) and SH3GLB1 (3, 4). Here we further dissected the role of SH3GLB1 in regulating the autophagic flux of CHRN. Upon sciatic denervation, we found a tight regulation of SH3GLB1/phosphorylated-T145 (p-T145) SH3GLB1 protein amounts. While p-T145 SH3GLB1 levels remained constant upon induction of muscle atrophy, the non-phosphorylated SH3GLB1 protein was increased. Overexpression of a T145 phosphomimetic mutant (T145E) of SH3GLB1 slowed down the processing of CHRN endolysosomes while as T145 phosphodeficient mutant (T145A) of SH3GLB1 strongly augmented it. The slow processing of CHRN endolysosomes brought about by T145E was rescued upon co-expression of the early endosomal orchestrator RAB5, suggesting a role of SH3GLB1 in regulating CHRN endocytic trafficking at steps upstream of autophagosome formation., Protein kinase CK2, a pleiotropic serine/threonine kinase, plays an important role in many different biological processes inside of cells.1 Conditional muscle-specific CK2 mutant mice lack grip strength and show muscle fatigability.2 We identified the role of CK2 in skeletal muscle cells as a regulator of neuromuscular junction maintenance by phosphorylation of different protein members of the postsynaptic apparatus.2,3 Moreover, CK2 is involved in ensuring proper mitochondrial homeostasis in skeletal muscle fibers by fine-tuning mitochondrial protein import through the translocase of the mitochondrial outer membrane. In absence of CK2-dependent phosphorylation of a mitochondrial outer membrane translocase protein, muscle fibers undergo accelerated mitophagy, as demonstrated by an up-regulated PINK/Parkin/p62 pathway., Mammalian neuromuscular junctions (NMJs) undergo a postnatal topological transformation from a simple oval plaque to a complex branch-shaped structure often called a “pretzel”. Although abnormalities in NMJ maturation and/or maintenance are frequently observed in neuromuscular disorders, such as congenital myasthenic syndromes (CMSs), the mechanisms that govern synaptic developmental remodeling are poorly understood. It was reported that myotubes, when cultured aneurally on laminin-coated surfaces, form complex postsynaptic machinery, which resembles that at the NMJ. Interestingly, these assemblies of postsynaptic machinery undergo similar stages in developmental remodeling from “plaques” to “pretzels” as those formed in vivo. We have recently demonstrated that podosomes, actin-rich adhesive organelles, promote the remodeling process in cultured myotubes and showed a key role of one podosome component, Amotl2. We now provide evidence that several other known podosome-associated proteins are present at the NMJ in vivo and are located to the sites of synaptic remodeling. Additionally, we identified proteins that interact with Amotl2 in muscle cells. We show that two of them: Rassf8 and Homer1, together with other podosome components, are concentrated at postsynaptic areas of NMJs in the indentations between the AChR-rich branches. Our results provide further support for the hypothesis that podosome-like organelles are involved in synapse remodeling and that Rassf8 and Homer1 may regulate this process. This research was supported by grants 2012/05/E/NZ3/00487, 2013/09/B/NZ3/03524 and 2014/13/B/NZ3/00909 from the National Science Centre (NCN)., The neuromuscular junction is one of the few human tissues capable of complete regeneration after major damages. We have set up a reliable model of acute degeneration of the motor axon terminals followed by complete recovery of function.2 We have found that alarmins released by mitochondria of the degenerating nerve terminal are key factor that act on the perisynaptic cells and muscle fibre.2 These cells are activated and release signals that act retrogradely on the nerve terminal inducing its regeneration. Some of these signals are currently being investigated by imaging and transcriptomics methods., Two fundamental differences exist between voluntary muscle contractions and those induced by electrical stimulation . During voluntary movements motor units are activated asynchronously and a strict hierarchical order of recruitment is always maintained where the smallest motor units are activated first followed by contractions of larger units. Thus during voluntary movement the largest motor units are least active and are used only during maximal effort. This order of recruitment is cancelled when electrical stimulation of the muscle is used; indeed due to the biophysical properties of the axons that innervate the muscle the largest motor units are activated preferentially and therefore the parts of the muscle that are usually used rarely are active most frequently. Thus during electrical stimulation it is the motor units that are normally least active that experience the biggest increase in their use and consequently the biggest change in their characteristic properties. Thus electrical stimulation by bypassing the hierarchical order of recruitment, indeed by reversing it, is able to activate those motor units and muscle fibres that can only be activated during most strenuous exercise. It can therefore exploit the adaptive potential of muscle more efficiently then exercise and maintain much higher levels of activity over time then exercise. This enhanced activity is restricted to specific target muscles and is unlikely to have unwanted systemic effects. Finally, high amounts of activity can be imposed on a muscle from the beginning, since the CNS, cardiovascular and other systems will not interfere or limit the amount of activity carried out by the muscle, as is the case during exercise (see for review Pette and Vrbová, 1999).1 On the other hand, there are several functions that electrical stimulation of individual muscle groups cannot accomplish and that are unique to exercise induced activity. During exercise-induced activity coordinated movement is carried out and it is therefore likely that the individual’s skills in carrying out movement of this kind will improve. Thus, while exercise can improve coordination, electrical stimulation is unlikely to do so. In addition the flexibility of joints and lengthening of muscles can be improved by exercise but not by electrical stimulation. Particular exercise regimes such as Pilates and yoga are particularly effective in achieving these goals. Improvement of the cardiovascular system is also easier achieved by exercise. Nevertheless, it can be argued that having muscles that are less fatiguable than usual, an advantage that is readily achieved by electrical stimulation, enables the individual to exercise more efficiently and achieve all the goals regarding fitness more readily and in a shorter time., Regular exercise and neuromuscular electrical stimulation (NMES) have been used in a variety of settings for different populations. Various modes of exercise (eccentric, concentric, resistance and aerobic) and NMES training regimes (localization, intensity, duration, frequency) exist for healthy subjects and athletes, patients in a variety of rehabilitation and preventive settings, either partially or in totally immobilized subjects. Both standard exercise interventions and NMES have been shown to be effective in preventing the decrease in muscle strength, muscle mass and the loss in oxidative capacity of skeletal muscles following multiple types of surgical (orthopedic) procedures. However, it is still not entirely clear whether biological adaptations are similar and the duration differences in their adaptation duration. We will discuss potential biological differences in adaption at the neuromuscular junction and potential differences in bioenergetics adaptation. Future research needs to determine potential molecular differences and beneficial post adaptation differences., Duchenne muscular dystrophy (DMD) is caused by loss of the force transmitting and membrane complex organizing protein, dystrophin, and is characterized by progressive muscle deterioration with failed regeneration and replacement with a fatty-fibrous matrix.1 Dystrophin replacement therapies to date have shown only limited ability to slow the disease process, and thus therapeutics targeting other aspects of the disease, which can be used in combination, are needed. One potential target is nuclear factor κB (NFkB, which is upregulated in the DMD muscles.2 We examined a novel class of NFkB inhibitors in mdx mouse and golden retriever muscular dystrophy (GRMD) dog models of DMD. These orally bioavailable compounds improved the phenotype of voluntarily run mdx mice, in terms of amount of activity, muscle mass and function, inflammation, and fibrosis. Surprisingly, the muscles were also more resistant to contraction-induced damage, which we demonstrated was significant increases in dysferlin, a protein required for membrane damage repair. We also evaluated the cardiac impact of a phosphodiesterase 5 (PDE5) inhibitor, tadalafil, which has been shown to improve blood flow in exercising skeletal muscles in mdx mice and human DMD patients.3 Cardiomyopathy is a leading cause of mortality among DMD patients and is well modeled by the golden retriever muscular dystrophy (GRMD) dog model of DMD. Prophylactic use of the PDE5 inhibitor, tadalafil, improved GRMD histopathological features of the hearts, decreased levels of the pathogenic cation channel TRPC6, increased phosphorylation of TRPC6, decreased m-calpain levels and indicators of calpain target proteolysis, and elevated levels of the dystrophin ortholog, utrophin. The progressive loss of cardiac function was significantly slowed by these effects. These data demonstrate that prophylactic use of tadalafil delays the onset of dystrophic cardiomyopathy, which is likely attributed to modulation of TRPC6 levels and permeability and inhibition of protease content and activity, which results in higher levels of the protective protein, utrophin. Thus PDE5 inhibition and NF-kB inhibition are potential therapeutics to consider in developing a combinatorial approach to the treatment of DMD., IGF-I and insulin are intrinsically connected through their actions on the IGF-I and insulin receptors to regulate blood glucose (1). Reduced circulating IGF-I can be compensated by heightened insulin, but chronically elevated insulin can lead to insulin resistance and ultimately diabetes . Further, increased circulating or local muscle IGF-I may enhance glucose uptake. If IGF-I from muscle and liver is equivalent, then loss of muscle IGF-I should result in a similar pathologic diabetic state (2). By extension, if muscle IGF-I is elevated, it may serve a protective role in glucose homeostasis, either through increased muscle mass providing a greater glucose sink (3), or through increased hybrid receptor activation by IGF-I (4). To address the impact that these factors have on metabolism, we elevated IGF-I by local AAV-IGF-I injections into both hindlimbs of adult male mice (5), and reduced muscle IGF-I through an inducible muscle specific deletion of Igf1. Mice were subjected to tests for body composition, glucose uptake, and energy expenditure compared to age-matched controls. It was not surprising that the hindlimb injections boosting IGF-I levels only in a small group of muscles did not alter the whole animal body composition. Further, when mice were subjected to treadmill running for 60 minutes, there were no significant changes in blood levels of glucose or lactate pre- or post-exercise. While increased muscle mass did not appear to alter basal glucose uptake, increased IGF-I content altered contraction induced glucose uptake in muscle when normalized to mass. To understand the consequences of diminished muscle IGF-I production, we generated mice with inducible muscle specific IGF-I deletion, with induction in adult mice. In mice with muscle specific deletion of Igf1, glucose levels following uphill treadmill running increased by 10%, in contrast to controls where blood glucose decreased by ~40%, supporting that glucose clearance is mediated in part through muscle IGF-I. Further, a marked impairment of glucose clearance occurred following a simple glucose tolerance test. Based on these results, we assert that the IGF-I produced by the muscle has an endocrine function, and like IGF-I produced by the liver, modulation of muscle levels of IGF-I will lead to changes in glucose homeostasis., Sarcopenia is the age-related loss of muscle mass, strength and function leading to loss of muscle power, which in the end results in frailty and disability. At molecular level, sarcopenia is a complex condition characterized by insufficient antioxidant defense mechanism, increased oxidative stress and altered function of respiratory chain (Fulle S., 2005). It has been hypothesized that the accumulation of oxidative stress is also related to an impaired regeneration cooperating to the atrophic state that characterizes muscle ageing (Beccafico S., 2007). To the purpose, we investigated the myogenic process in satellite cells, the skeletal muscle stem cells, as myoblasts and myotubes collected by human Vastus Lateralis skeletal muscle of young and old subjects through needle-biopsies (Pietrangelo T., 2011). NBT and H2DCF-DA assays were used to measure O2•- and ROS production, respectively. Data revealed that oxidant species are more concentrated in elderly myoblasts compared to young ones. To evaluate if mitochondria are affected by ROS using JC-1 assay we found that in elderly myoblasts mitochondrial transmembrane potential decreases much more than in young ones probably due to their lower endogenous antioxidant abilities. Furthermore, MitoSOX™ Red reagent was used to measure directly O2•- in mitochondria. We found that in elderly myoblasts O2•- production is increased respect to young ones and the result is worsened in myotubes. Gene expression analysis revealed that genes involved in atrophic and ubiquitin-proteasome pathways were upregulation together with the dysregulation of the proliferative one suggesting an alteration at gene expression level in elderly myoblasts vs young ones (Pietrangelo T., 2009). In an attempt to ameliorate muscle regeneration in elderly mitochondrion-specific liposomes carrying antioxidant were synthetized. The toxicity of liposomes were tested on human satellite cells and C2C12 cells, a murine skeletal muscle cell line. Preliminary results demonstrated that liposomes made using DPPC 97.5%/BOLA 2.5% gave the lowest toxicity at 24-48-72 hours. Overall, if we need more data and further analysis, up to day our data suggest that oxidative stress impairs muscle regeneration in elderly subjects., The sarcoplasmic reticulum (SR) is organized in longitudinal and junctional SR (j-SR). In skeletal muscle, this latter domain together with the T-tubules form specific junctions called triads, where proteins regulating the excitation-contraction coupling mechanism assemble. Junctophilins (JPs) are directly involved in the formation and maintenance of triads. Basically, they are anchored to the SR via their C-terminal transmembrane domain (TMD), while their N-terminus contains eight MORN motifs, which associate with the phospholipids of the T-tubules. Nevertheless, how JPs are targeted to triads is not known. The roles of the N-terminal and the C-terminal regions of JP1 in this process were investigated. Expression in primary myotubes and/or muscle fibers of JP1 deletion mutants lacking the TMD resulted in protein distribution at both the surface sarcolemma and the T-tubules, confirming that MORN motifs are involved in JP1 interaction with the sarcolemma, but are not sufficient to restrict its localization at the T-tubules. On the other hand, progressive deletion of the eight MORN motifs or even of the entire cytosolic region, did no affect JP1 localization at triads, indicating that the presence of the TMD is sufficient for JP1 localization at the j-SR. FRAP analysis performed on a GFP-TMD fusion protein expressed in myotubes indicated that this protein has a high mobility, suggesting the absence of strong protein-protein interactions occurring at the j-SR. Further work is needed to better understand the molecular mechanisms driving TMD-mediated JP1 localization at triads., Physical Calsequestrin (CASQ) is the major protein of the sarcoplasmic reticulum of striated muscle that binds Ca2+ with high capacity and moderate affinity. CASQ exist as a monomer and polymers, depending on Ca2+ concentration. CASQ switches from an unfolded state to a folded monomer when the ionic strength increases allowing the formation of front-to-front first and then back-to-back interactions in higher Ca2+ concentrations. Recently we reported one mutation in the skeletal CASQ1 gene in a group of patients with a vacuolar myopathy characterized by the presence of inclusions containing CASQ1 and other SR proteins. The CASQ1 mutation (CASQ1D244G) affects one of the high-affinity Ca2+- binding sites of the protein and alters the kinetics of Ca2+ release in muscle fibers from patients. Expression of the CASQ1D244G in myotubes and in mouse fibers causes the appearance of SR vacuoles containing aggregates of the mutant CASQ1 protein that resemble those observed in patients. Studies of Ca2+ release showed an increase in Ca2+ storage in CASQ1WT COS-7 transfected cells whereas no increase was observed in CASQ1D244G. Moreover both CASQ1WT and CASQ1D244G were expressed in bacteria, purified and analysed for their ability to polymerize at increasing Ca2+ concentrations. The results obtained indicate that the CASQ1D244G protein polymerizes at lower Ca2+ levels and more rapidly than CASQ1WT. These results suggest that the CASQ1D244G mutation interferes with the correct process of Ca2+-dependent protein polymerization causing altered intracellular calcium storage and the formation of protein aggregates., Store-operated Ca2+ entry (SOCE), also referred to as capacitative Ca2+ entry, plays an important role in intracellular Ca2+ regulation. SOCE is a ubiquitous Ca2+ entry mechanism, first described in non-excitable cells, that is triggered by depletion of intracellular Ca2+ stores (endoplasmic/sarcoplasmic reticulum, respectively ER and SR). SOCE is coordinated by the interaction of stromal interaction molecule 1 (STIM1), which acts as the Ca2+ sensor in the ER lumen,1 and Orai1, the Ca2+-permeable channel in the plasma membrane (PM).2 Specific Gap of Knowledge. SOCE is also well-documented in skeletal muscle,3 where it limits muscle fatigue during repetitive fatiguing stimulation.4 Several studies suggest that STIM1-Orai1 coupling occurs within the pre-formed SR-TT junctions of the triad,5 also known as Ca2+ release units (CRUs), the sites of excitation-contraction (EC) coupling. However, the precise subcellular location of STIM1-Orai1 SOCE complexes in skeletal muscle has not yet been unequivocally identified. Recent breakthroughs. Here we show by electron microscopy (EM) that prolonged muscle activity drives the formation of previously unidentified intracellular junctions between the SR and extensions of the TTs membrane. The activity-dependent formation of these unique SR-TT junctions reflects a striking and unexpected remodeling of the existing sarcotubular system at the I-band of the sarcomere. Using immunohistochemistry and immunogold labeling for EM we demonstrate that these junctions contain the molecular machinery known to mediate SOCE: STIM1 in the SR and Orai1 channels, which move into the I band as a result of the elongation of existing TTs. Thus, these newly formed junctions are referred to as Ca2+ Entry Units (CEUs), the first new, molecularly-defined subcellular structure in skeletal muscle in over 30 years. We propose that CEUs: a) play a fundamental role in coordinating STIM1-Orai1 coupling in muscle, b) represent the structural framework for SOCE providing an ideal Ca2+ entry pathway to refill SR stores, and c) plays a key role during repetitive stimulation., Deep brain stimulation (DBS) of the subthalamic nucleus (STN) or globus pallidus internus (GPi) is now an established, safe and effective treatment option for Parkinson’s disease (PD), used by more than 125,000 patients worldwide. Solid scientific evidence indicates that it can significantly alleviate motor disability, levodopa-induced complications and improve a patient’s overall quality of life. The indications for DBS have expanded in recent years, including earlier application in Parkinson patients, use in other motor disorders such as dystonia and essential tremor, and the potential for use in intractable epilepsy and psychiatric disorders, for example. In Parkinson patients DBS produces a marked improvement in motor fluctuations and dyskinesias even if evidence suggests that the reduction in motor disability is greater with medications than with STN-DBS. Benefits associated with DBS persists for many years, although disability still progresses, reflecting degeneration in non-dopaminergic sites. It is noteworthy, however, that the use of DBS is limited not only by several restrictive exclusion criteria, but also by the comparatively high risk of severe complications, such as neuropsychiatric morbidity, intracranial bleeding (which can occur in 2-8% of patients undergoing stereotactic neurosurgery), and in some cases increased mortality., EC coupling in muscle links the transverse(T)-tubule depolarization to release of Ca2+ from the sarcoplasmic reticulum (SR).1-2 These membranes communicate in specialized structures, i.e. calcium release units (CRUs), thanks to a cross-talk between voltage-dependent Ca2+ channels CaV1.1 (or dihydropyridine receptors, DHPRs) in the T-tubule and Ca2+ release channels, or ryanodine receptors type-1 (RYR1), in the SR.3-5 Mutations in the gene encoding for RYR1), the SR Ca2+ release channel, underlie debilitating, life-threatening muscle disorders such as central core disease (CCD) and malignant hyperthermia (MH). To date, MH is only seen as a clinical syndrome in which genetically predisposed individuals respond to volatile anesthetics in the operating room with potentially lethal episodes characterized by elevations in body temperature and rhabdomyolysis of skeletal muscle fibers. However, virtually identical over-heating episodes have been reported in individuals also after exposure to environmental heat, physical exertion, or even during febrile illness. The life-threatening nature of EHS underscore the critical need for a deeper mechanistic understanding of these syndromes and for the development of new and effective treatments. Specific Gaps of Knowledge. A) Mutations in RYR1 have been found in many, but not all, MH cases suggesting the potential involvement of additional genes in the pathogenesis of this syndrome. B) The relationship between classic MH and overheating episodes triggered by different stressors (heat, exertion, fever, etc.) is not yet widely recognized. C) The cascade of molecular mechanisms that from SR Ca2+ leak leads to rhabdomyolysis of muscle fibers are still unclear and needs to be fully elucidated. Recent breakthroughs. In the last years, thanks to the support of Telethon (GGP08153 and GGP13213), we have moved significant steps forward. We have demonstrated in animal models that: A) MH episodes can result not only from mutations in RYR1, but also from mutations in proteins that interact with RYR1 (such as Calsequestrin-1, CASQ1); B) the mechanisms underlying hyperthermic episodes triggered by anesthetics and by heat and exertion are virtually identical, suggesting that these syndromes could be possibly treated/prevented using similar treatments; C) during lethal MH/EHS crises Ca2+ leak from intracellular stores results in a feedforward mechanism mediated by excessive production of oxidative species of oxygen and nitrogen (ROS and RNS), which eventually will lead to depletion of the SR and to massive activation of Store Operated Ca2+ Entry (SOCE)., A crucial system severely affected in different pathological conditions is the antioxidative defense, leading to accumulation of ROS. The discovery that the anti-oxidant status decreases with age and it is affected in several pathological conditions, such as disuses, chronic fatigue syndrome, cancer, muscular dystrophy and amyotrophic lateral sclerosis (ALS), has placed oxidative stress as a central mechanism in the pathogenesis of these diseases. A critical aspect underlying the mechanisms of age-related muscle loss is the reduction in the number of nerve terminals, fragmentation of the neuromuscular junctions (NMJs), and a decrease in neurotransmitter release. However, considering that skeletal muscles in one of the tissues that generate considerable ROS, an important issue to address is whether a selective alteration of oxidative stress balance in skeletal muscle is sufficient to induce these alterations. Preliminary results demonstrate that muscle specific accumulation of oxidative stress induces mitochondria dysfunction/alterations and triggers NMJs dismantlement, associated with higher rate of Acetilcholine Receptor (AchR) turnover and morphological alterations of the pre-synaptic neuromuscular endplate. We also defined the potential molecular mechanisms that mediate the toxic effects of oxidative stress and NMJs dismantlement., Physical exercise is known to have beneficial effects on muscle trophism and force production modulating signaling pathways involved in fiber type and muscle growth also via intracellular Ca2+ and inducing specific mitochondrial adaptations. Several evidences both in vitro and in vivo, have demonstrated that during muscle contraction, Ca2+ concentration in the mitochondrial matrix is increased. Importantly, alterations of mitochondrial Ca2+ homeostasis controlled by mitochondrial calcium uniporter (MCU) has been recently shown to regulate muscle mass in vivo in mice. In skeletal muscle, mitochondria exist as dynamic network that is continuously remodeled through fusion and fission phenomena that are important for maintenance of functional mitochondria. In particular, fission occurs upon the recruitment of dynamin-related protein 1 (DRP1), while fusion is controlled by mitofusins (MFN) 1 and 2 and by optic atrophy 1 (OPA1). OPA1 also regulates mitochondrial adaptations to bioenergetic conditions at the level of inner membrane ultrastructure and remodeling of mitochondrial cristae, controlling muscle atrophy and mitochondria respiratory efficiency. It has been shown that the decrease of muscle mass and strength observed in age-related Sarcopenia is linked to abnormalities of mitochondrial morphology, number and function. In the present study we intended to investigate the effects of 9 weeks strength training by neuromuscular electrical stimulation (ES) in comparison to voluntary leg press (LP) in sedentary 70yrs old subjects on mitochondria dynamics, MCU and mitochondria respiratory chain enzymes modulation. Our results show that ES mediated muscle structural and functional improvements are linked to signaling pathways related to muscle mass regulation and enhanced MCU, and COX IV respiratory chain enzyme. Electron Microscopy ultrastructural analyses showed remodelling of mitochondrial apparatus as a consequence of fusion phenomena that is consistent with adaptation to physical exercise and with increased OPA1 protein expression levels as documented by WB analyses. LP training showed moderate effects both at structural and functional level, with no impact on mitochondrial dynamics, that are consistent with a milder protocol of training in comparison to neuromuscular ES. Altogether these results indicate that the ES-dependent beneficial effects on muscle mass and force are associated with changes in mitochondrial-related proteins involved in Ca2+ homeostasis and mitochondrial shape, providing new targets to develop therapeutic strategies counteracting Sarcopenia and promoting healthy ageing., Skeletal muscle atrophy is a debilitating loss of muscle mass (resulting from decreased myofiber size) and strength that normally occurs during aging, muscle disuse / inactivity, neuropathies / myopathies and with other pathological diseases. The ether-a-gogo related gene (ERG1a) is a K+ channel that is up-regulated in atrophying gastrocnemius muscles of both unweighted and cachectic mice.1 Ectopic expression of mouse erg1a (Merg1a) in mouse muscle increases ubiquitin proteasome activity by up-regulation of at least one known E3 ligase, MuRF1.2 Because Murf1 expression is up-regulated by increased NFκB activity3, we hypothesized that ectopic expression of Merg1a would increase NFκB activity and lead to increased Murf1. To test this, we electro-transferred plasmid encoding an NFκB firefly luciferase (FFL) reporter and a second plasmid encoding Renilla luciferase (Ren) into mouse gastrocnemius muscles. We added a Merg1a plasmid in the left leg while adding a control plasmid in the right. We then harvested muscle on days 0-7 and assayed for both FFL and Ren activities and used the FFL to Ren ratio as a measure of NFκB activity (to correct for differences in transfection efficiency). Surprisingly, the muscles expressing Merg1a showed a decreased NFκB activity when compared to the controls. Thus we hypothesized that there may be a factor present in a physiological model of atrophy that would cause MERG1a to modulate NFκB activity differently. Because sciatic nerve transection does not produce an increase in Merg1a expression, but it increases NFκB activity3, we repeated our electro-transfer with mice and then denervated both legs 18-24 hours later. We harvested muscles at days 0, 2, 4, 7 and 10 post-denervation. The Merg1a treated muscle still experienced a decrease in NFκB activity. Thus, we conclude that ectopic expression of Merg1a modulates NFκB activity in both innervated and denervated skeletal muscle. Future studies will include efforts to determine if this finding is truly physiological and, if so, then by what mechanism does MERG1a affect NFκB activity., Physical activity plays an important role in preventing chronic disease and muscle degeneration in adults and the elderly persons.1 Age-related changes in skeletal muscle innervation, independent of patent peripheral neuropathies, are known to contribute to the decline in quality of life often reported in older population.2 The changes and the mechanism(s) by which they occur are not well understood. We had the opportunity to examine the effects of lifelong high-level physical activity comparing cohorts of young adults and septuagenarians either sedentary or recreational sportsmen, collecting what is, in our opinion, strong evidence that aging atrophy is, at least in part, a result of progressive denervation that can be counter-acted by lifelong high-level exercise.3 We used immunolabeling methods to analyze the fiber type composition of muscle biopsies. Our main results demonstrate that biopsies from: 1. young men seldom contain denervated (0.2±0.5 %), or transforming muscle fibers (0.5±0.6 %); 2. sedentary seniors contain both denervated (2.6±1.9 %), coexpressing myofibers (1.8±1.7 %) and a few reinnervated clustered myofibers of the fast type (3.0±4.7 %); and 3. senior sportsmen present with a larger percentage of healthy, slow myofibers (up to 68.5±14.1 %,) that appear mainly clustered in slow fiber-type groupings (7.9±7.4 %).4,5 Data analysis reveals that there was no difference between the athletic and sedentary senior groups in terms of their very low percentages of muscle fibers co-expressing fast and slow MHCs (0.6±0.6 %), suggesting that lifelong exercise does not induce motor unit transformation. On the other hand the recreational sportsmen had both considerably higher percentages of slow-type myofibers and greater numbers of slow fiber-type groupings, providing sound evidence that lifelong cycles of denervation/reinnervation occurred. It appears that lifelong exercise protects muscle function by saving otherwise lost muscle fibers through reinnervation by different, mainly slow, motor axons.6 On the other hand, volitional exercise is not always feasible or people are reluctant to do it and other strategies should be applied such as Functional Electrical Stimulation (FES).7 This study shows the effects in situ of FES in human Vastus Lateralis (VL) muscle of sedentary elderly people, in particular on the key process of Ca2+ uptake and release and related control mechanisms that are essential in muscle adaptation. Through immunofluorescence analysis of muscle cryosections, a huge increment of NFAT positive nuclei was found after treatment (from 3% to 60%); moreover an increment of P-CamkII was observed by western blotting analysis. These findings indicate that FES activate the CaM-dependent phosphatase signaling (known to be involved in muscle plasticity). Muscle total homogenates were obtained from biopsies performed before and after completing a nine weeks FES treatment on a group of volunteers and Calsequestrin (CASQ), SERCA, Sarcalumenin, protein expression was determined by Western blot. After FES significant increase of SERCA2 and Sarcalumenin and decrease of CASQ1 were observed. Immunofluorescence analysis were also performed to localize in situ MHCII/SERCA2 co-expressing muscle fibers, an interesting tool to identify subpopulation of muscle fibers involved in muscle adaptation. The overall results indicate that the applied FES protocol, simulating a motoneuron slow-type firing pattern, potentiates Ca2+ uptake and storage in skeletal muscle fibers validating at molecular level the FES strategy as a safe and effective rehabilitation strategy in elderly persons., The Tat protein is able to translocate through the plasma membrane and when it is fused with other peptides may act as a protein transduction system. This ability appears particularly interesting to induce tissue-specific differentiation when the Tat protein is associated to transcription factors. In the present work the potential of the complex Tat-MyoD in inducing equine peripheral blood mesenchymal stromal cells (PB-MSCs) towards the myogenic fate, was evaluated. Results showed that the internalization process of Tat-MyoD needs the absence of serum and the nuclear localization of the fused complex is observed after 15 hours of incubation. However, the supplement of Tat-MyoD only was not sufficient to induce myogenesis and, therefore, in order to achieve the myogenic differentiation of PB-MSCs, conditioned medium was added. The latter was obtained coculturing PB-MSCs with C2C12 without a direct contact. These results suggest that TAT-mediated protein transduction system, if supported by conditioned medium, might represents a useful methodology to induce myoblasts differentiation., Both strength and power developed by human skeletal muscles decline with increasing age.1,2 The athletic world records of the Master athletes of age ranging from 35 years to 100 years are an excellent proof of such decline in every track and field competition. The world record performances of running, jumping and throwing events can be transformed into dimensionless parameters proportional to the power developed in the trials. Such parameter ranges from 1 for the Senior world record (i.e. the maximum human performance) to lower values for the Master athletes of increasing age down to 0 for a null performance.3,4 With this procedure the declines of the power parameter with increasing age can be analysed and compared: the trend-lines start to decline very close to the age of 30 years and arrive to 0 around the age of 110 years for every athletic discipline (running, jumping and throwing).5 The comparison of the various trend-lines show significantly different rates of decline. Each declining trend-line reaches a “critical” threshold at different ages for the running, jumping and throwing activities. Such thresholds indicate different age limits for most of everyday tasks: walking, climbing stairs and lifting weights above a table. The decline of the Master world records, transformed into a dimensionless power parameter declining from 1 toward 0 with increasing age is the decline of the power developed by each one of us, starting from 1 in our youthful age and declining toward lower values with increasing age. There are no reason, for each one of us, to decline differently from the world record-men, provided that each of us remains in stable fitness condition without disabling pathologies., We present a case report of atypical amyotrophic neuralgia of the suprascapular nerve with isolated denervation atrophy of rotator cuff muscles and related biomechanics impairments of the shoulder. The patient, lamenting yearly-long unsatisfactory results of standard clinical physiotherapy, after a baseline re-evaluation at our hospital, have been treated for the last seven months with an additional personalized home-based Electrical Stimulation protocol using triangular currents for denervated muscles. At the end of the follow up we observed clinical, radiological (False-color CT)1 and neurophysiological (needle-EMG)2 improvements. The case report provides the opportunity to discuss a rehabilitative pathway for diagnostics and rehabilitation of patients suffering of peripheral denervation, a condition that is still a challenge for clinicians., The Chronic low back pain (CLBP) is a disabling condition affecting a majority of people of the western countries. It also deeply affects the quality of life as it is often linked to multidimensional disturbances such as poor sleep, mood disorders, chronic fatigue and joint pain. There is no condition with higher social and economic expenses. It has been reported that only a minority of patients with gut inflammation suffers from intestinal symptoms. In a previous paper it was proposed that gastrointestinal disturbances, beyond mechanical issues, could be overlooked in the management of these patients. Dietary changes were successful in the positive resolution of the described clinical case. Here we further test this hypothesis. We measured on 5 subjects specific parameters related to gastrointestinal and digestive physiology that have been associated with metabolic and immuno-related pathological conditions. Inflammation in the gut can lead to altered mucosa permeability. The entrance in the blood stream of abnormal molecules activates the immune system in a cascade of events affecting remote systems and possibly the integrity of structures like the neuromuscular junction or the pathways of energy production. Conditions that are currently managed by orthopaedists, reumatologists and neurologists could benefit from a screening of the gastrointestinal functionality., In the last decades, a growing body of literature focused on the use of mechanomyography (MMG) as a means to study non-invasively skeletal muscle mechanical activity. MMG signal is detectable at the skin surface during the dimensional changes of active muscle fibres that generate pressure waves due to voluntary or evoked contractions.1,2 A novel application is the use of an electromyographic (EMG), MMG, and force (F) signals combined approach as a tool to partition the electrochemical and mechanical events underpinning the electromechanical delay during muscle contraction (EMD) and relaxation (R-EMD).3,4 This approach has been utilized to evaluate the changes in the electrochemical and the mechanical components of EMD and R-EMD under several physiological conditions (local fatigue, muscle temperature manipulation and muscle-tendon unit stretching). Under all these circumstances, the approach presented a high reliability and sensitivity. Myotonic dystrophy type 1, the most frequent form of inherited muscular dystrophy5 involves a broad spectrum of systemic complications. The main features at the skeletal muscle level are muscle weakness and grip and percussion myotonia. Distal muscles are generally more compromised than the proximal ones. In clinical settings, muscle weakness and myotonia are usually determined on patients with DM1 qualitatively or semiquantitatively by the Medical Research Council scale, by dynamometry, and/or by physician’s handgrip evaluation. Hence, a valid, non-invasive, and reliable tool to assess the degree of muscle dysfunction in DM1 could be of great interest for clinical trials involving new therapies. Therefore, the aims of the study were: (i) to assess the reliability and sensitivity of the measurement of the electromechanical delay components during both contraction and relaxation in patients with DM1; and (ii) to evaluate and discuss possible differences in delay components’ duration between patients with DM1 and healthy, age-matched controls (HC). EMD and R-EMD electrochemical and mechanical components duration and reliability of the measurements were investigated during skeletal muscle contraction and relaxation in a group of patients with DM1 (n = 13) and in healthy controls (n = 13). EMG, MMG, and F were recorded from the tibialis anterior (distal muscle) and vastus lateralis (proximal muscle) muscles during maximum voluntary and electrically-evoked isometric contractions. The electrochemical and mechanical components of the electromechanical delay during muscle contraction and relaxation were calculated off-line. Maximum strength was significantly lower in DM1 than in controls under both experimental conditions. All electrochemical and mechanical components were significantly longer in DM1 in both muscles. Measurement reliability was very high in both DM1 and controls. The high reliability of the measurements and the differences between DM1 patients and controls suggest that the EMG, MMG, and force combined approach could be utilized as a valid tool to assess the level of neuromuscular dysfunction in this pathology, and to follow the efficacy of pharmacological or nonpharmacological interventions., The optimum metric for assessing changes in skeletal muscle quality remains debated. Identifying a novel quantitative method for muscle assessment in this regard would allow for the generalizability of such studies to clinical practice and therefore aid in the indication of compensatory targets for clinical intervention.1-3 While there is much extant literature reporting the use of average HU values to investigate muscle quality and its utility as a comorbidity index, no studies have yet to utilize the entire radiodensitometric distribution. The increasing prevalence of sarcopenic and cachexic muscular degeneration necessitates the establishment of a robust quantitative muscle assessment methodology. Herein, we hypothesize that rigorously quantifying entire HU distributions can elicit much more information regarding muscle quality than extant methods that, to date, only utilize average HU attenuation values. This study reports the development and use of this method, wherein we assess upper leg muscle quality utilizing nonlinear trimodal regression analysis with radiodensitometric distributions from computed tomography (CT) scans of a healthy young adult, a healthy elderly subject, and an SCI patient with complete lower motor neuron denervation. Results from this assessment highlight the utility of utilizing entire HU attenuation value distributions and identify novel parameters from these analyses that could provide further insight into how muscular degradation can be optimally quantified., During the last decade we contributed to rehabilitation in aging studying effects of physical exercise induced by Functional Electrical Stimulation (FES) in the special case of Spinal Cord Injury patients affected by complete injury of the Conus Cauda, a syndrome in which the denervated leg muscles are fully disconnected from the nervous system. Denervated human muscles become unexcitable with commercial electrical stimulators and undergo ultra structural disorganization within a few months from SCI, while severe atrophy with nuclear clumping and fibro-fatty degeneration appear within 3 and 6 years, respectively.1-4 To counteract these progressive changes a novel therapy concept for paraplegic patients with complete lower motor neuron denervation of the lower extremity was developed in Vienna: home-based functional electrical stimulation of long-term denervated muscles (h-b FES). New electrodes and a safe stimulator for h-b FES have been designed to reverse severe atrophy by delivering high-intensity (up to 2,4 J) and long- duration impulses (up to 150 ms) able to elicit contractions of denervated skeletal muscle fibers in absence of nerves.5,6 Specific clinical assessments and trainings were developed at the Wilhelminenspital Wien, Austria,7 based on sound evidence from animal experiments.8 Main results of the clinical study on patients which completed the 2-year h-b FES training were: 1. significant increase of muscle mass and of myofiber size, with striking improvements of the ultra- structural organization; 2. recovery of tetanic contractility with significant increase in muscle force output during electrical stimulation; 3. capacity to perform FES-assisted stand-up and stepping-in-place exercise.9-12 The study demonstrated that h-b FES of permanent denervated muscle is an effective home therapy that results in rescue of muscle mass, function and perfusion. Additional benefits are improved leg cosmetic appearance and enhanced cushioning effect for seating., Functional recovery after peripheral nerve injury is reduced when axon growth is misdirected to reinnervate muscles other than their original targets.1-3 Here we review the effects of chronic electrical muscle stimulation (EMS) following peripheral nerve injury in rat, canine, and equine models of peripheral nerve injury. Specifically, we examine whether EMS accelerates reinnervation of muscular targets and if these targets are appropriately reinnervated by their original axons following nerve injury. Methods: In the Sprague Dawley rat, the lateral gastrocnemius nerve was transected and immediately repaired. The soleus muscle was implanted with electrodes and connected to a mini stimulator implanted intraabdominally. Muscles were stimulated daily using a 12-hour day time pattern of a 10 second burst of 20 Hz once per hour followed by a 12-hour night time pattern of 20 Hz (10 seconds on, 20 seconds off). This stimulation pattern was delivered for 2 months. Appropriate reinnervation of the soleus muscle was assessed using retrograde labeling of the soleus nerve. Functional recovery was assessed by measuring isometric soleus muscle forces. In the dog, the recurrent laryngeal nerve was transected bilaterally and immediately repaired. Electrodes were implanted to stimulate the posterior cricoid arytenoid (PCA) muscles bilaterally. Muscles were stimulated continuously using either a 10 or 40 Hz pulse train for ninety days. Appropriate reinnervation was measured using electromyography methods. Functional recovery was assessed using a treadmill exercise test and vocal fold movement during hypercapnia. In the horse, the right recurrent laryngeal nerve was injured using a stainless steel probe pre-chilled in liquid nitrogen and placed on the nerve for two minutes. Electrodes were implanted into the right PCA muscle and connected to an implanted stimulator. Muscles were stimulated for one hour once every 12 hours at 22 Hz (3.5 seconds on, 6.5 seconds off) for twenty weeks. Functional recovery was assessed using a treadmill exercise test and examining arytenoid abduction and tracheal inspiratory pressure endoscopically. Results: Retrograde labeling in the rat, demonstrated that EMS of the soleus muscle had no effect on directing the original soleus neurons back to reinnervate the muscle following nerve injury and repair. Muscle twitch forces were significantly greater, however, tetanic forces were not different whether the muscle was stimulated or not. In the dog, progressive addition of samples to the study showed that exercise tolerance and glottal area following hypercapnia was maximal in dogs that received PCA stimulation at 10 Hz.4 EMG measurements in 3 dogs suggest that PCA muscles stimulated at 10 Hz were preferentially reinnervated by their original motoneurons whereas those muscles stimulated at 40 Hz or were unstimulated had random reinnervation. Horses that had the PCA muscle stimulated had improved function as demonstrated by lower negative tracheal inspiratory pressures. These improvements occurred sooner after injury and at lower exercise intensities than horses that did not have the PCA muscle stimulated. However, functional recovery returned to near baseline in all horses suggesting that the original nerve injury was not severe enough. Conclusions: Despite stimulating the soleus muscle in rats using a pattern resembling natural activity before and during the time of reinnervation, EMS did not encourage the original motoneurons that were connected to the stimulated muscle to return. However, in the dog, 10 Hz stimulation promoted selective reinnervation. One limitation in the dog study is the small sample size which needs to be expanded to provide adequate statistical power. In the horse, EMS enhanced the speed of functional recovery despite a nerve injury that was not as severe as one in both dogs and rats. Nevertheless, in all animal models stimulation did not negatively impact functional recovery with muscle forces in the rat being higher with stimulation and dynamic airway measurements being enhanced in both dogs and horses that had their muscles stimulated following nerve injury., The cellular mechanisms underpinning the maintenance, gain and loss of muscle mass are of great interest at present, given the popularity of bodybuilding, the potential for increased muscle metabolism to reduce the damage caused by diabetes and insulin resistance, and the key role of muscle function associated with the decline in mobility and well-being associated with ageing. There are many model systems in which to make experimental investigations of muscle hypertrophy in rodents.1-9 It is generally considered that increased average force generation (loading) is important, although hypertrophy can be achieved in some muscles by pharmaceutical agonism of the androgen receptor family, or by genetic manipulation of, for example, the response to IGF. Models have included removal1,2,3 or denervation of agonists to generate constant overload, various training modalities such as squats,3 lifting,4,5 or jumping for a food reward, and treadmill or ladder climbing exercise,6 sometimes with added weight7 to increase the muscular effort. We have designed a hypertrophy model using programmed exercise by stimulating agonists and antagonists simultaneously. In the rat hind limb, the dorsiflexor muscles that lift the foot are supplied by the common peroneal nerve whereas the plantarflexor muscles are supplied by the tibial nerve. The plantarflexors are the larger and stronger group so it is possible to generate loaded contractions of the dorsiflexors by activating them fully at the same time as a partial activation of the plantarflexors. We have achieved this with a single channel implant by careful positioning of the electrodes with the cathode under the common peroneal nerve and the anode near to the tibial nerve as it runs on the proximal posterior surface of the gastrocnemius muscle. The key to success in this model is the ability to adjust remotely the stimulating current and to choose a stimulation pattern that generates high force contractions with minimal disturbance to the subject. Using the new miniVStim device developed between Vienna and Liverpool we are able to programme an ‘adaptation’ pattern so that the subject is accustomed to the sensation of muscle activation at a low level before the loaded contractions are made. With stimulation in one session per day of 5 sets of 10 repetitions at 100Hz (2s ON 2s OFF) and 2.5 minutes between sets, we have achieved hypertrophy of the tibialis anterior muscle giving an increase in wet weight of between 11,5 and 13,7% in 5 rats over 4 weeks. We will use this model to investigate further the sensitivity to hypertrophy of the various fibre types and the cellular pathways that are activated in this response., One of the main determinants of the size of neural implantable pulse generators is the size of the battery. The challenge for engineers is to design devices that are small in volume whilst fulfilling their stimulation task as long as possible. Efficient stimulation methods are crucial for their success. Wongsarnpigoon pointed out three different types of efficiency relating to nerve activation.1 A “charge-efficient” stimulation has the positive effect of reducing tissue damage. As the battery size is proportional to the maximal instantaneous power required, “power-efficient” stimulation could reduce battery-size and therefore the overall size of an implant. An “energy- efficient” stimulation on the other hand, increases the battery lifetime. We have compared different waveforms according to their “energy-efficiency”. Six different waveforms have been investigated (rectangular monophasic, rectangular biphasic, rectangular biphasic with interphase gap, gaussian biphasic, exponential biphasic, asymmetric rectangular biphasic with interphase gap) to clarify some of the potentially useful efficiencies noted in other studies.2-7 Another interesting aspect that has been investigated in our latest experiments, is a comparison between monopolar and bipolar stimulation, and some investigation of the transition between the monopolar and the bipolar configuration in terms of stimulation efficiency. For bipolar stimulation, two stainless-steel loop electrodes were placed under the common peroneal nerve of rats under buprenorphine/isofluorane anaesthesia. In the monopolar situation the anodal electrode was a hypodermic needle placed under the skin more than 50mm away from the cathode. The cathode was the same in both cases. The isometric force produced at optimal length by the extensor-digitorum-longus muscle was measured using a load-cell. Our results showed a noticeable difference between monopolar and bipolar stimulation. Monopolar stimulation showed generally higher energy levels than bipolar stimulation to activate the motor neurones of the common peroneal neve. While the introduction of an interphase-gap increased the threshold current, where the force was 10% of the control-force, in the bipolar case, a reduction was observed in the monopolar situation. In previous bipolar experiments we found an increased energy requirement for threshold activation with asymmetric waveforms while the monopolar stimulation again showed a reduction. The results show similar effects as described in literature when using monopolar stimulation. Nevertheless we achieved different results for the bipolar stimulation regime. It is therefore important to bear these differences in mind, when designing electrodes and patterns of stimulation to improve stimulation efficiency., According to PubMed roughly 10% of the annually added publications in the Life Sciences describe findings obtained from animal models. Since half of these studies are done in mice and rats it can be assumed that there is a need for implantable electrical stimulators which are flexible, reliable and small enough (~1 cm3) that implantation is possible in mice. It is important that animals do not have to be isolated during stimulation periods and that they can run freely. MiniVStim 12A is a battery powered implantable electrical stimulator able to deliver constant current monophasic, rectangular pulses up to 2mA and 1ms pulse width (@1kOhm). It is easy to use because the required stimulation pattern is preprogramed during manufacturing. On, off or different stimulation patterns can be cyclically activated with a strong magnet, also through the skin. This implant has an outer diameter of 15 mm and a volume of 1.2 cm3. MiniVStim 12B has the same mechanical dimensions but can be fully programed via a transcutaneous bidirectional data link. Both types of implants are already successfully used in studies.1 The latest generation of implants is represented by the new MiniVStim18B. It is slightly larger (22mm outer diameter, 5.3 cm3) than its predecessors but offers an 8 fold longer battery life. Additionally, it can deliver biphasic constant current pulses and extends the stimulation parameter range up to 8mA at a maximum output voltage of 10V and with a pulse width of 5ms (@1kOhm) for monophasic and 2x5ms for biphasic pulses. Lifetime is strongly dependent on the chosen stimulation pattern. For example, monophasic stimulation with a duty cycle of 20% (20% on, 80% off time) and 2mA, 100Hz, 250µs pulse width, 1kOhm load, leads to a battery lifetime of 300 days and when stimulating with 8mA life time comes to 70 days. Under the same circumstances except choosing stimulation frequency of 10Hz a lifetime of 1000 days and 450 days could be expected. The very low standby current consumption (, Muscle atrophy as part of the ageing process also affects the larynx, where it constitutes the major cause of presbyphonia. Current treatment options are mainly conservative or phonosurgically based and are far from being satisfactory. Electrical stimulation of motor neurons constitutes a promising strategy. Materials and Methods: Using aged sheep as an animal model electrical chronic stimulation of laryngeal muscles was achieved via a mini-electrode that targeted the right recurrent laryngeal nerve (RLN; unilateral stimulation). Functional electrical stimulation (FES) implants were programmed to deliver a pattern able to evoke supramaximal muscle stimulation over a period of 29 days. At the end of the study, vocalis and posterior crico-arytenoid muscles were excised and analyzed molecularly and histologically. To quantify the expression levels of genes related to distinct muscle fiber types, a real-time PCR (RT-qPCR) analysis pipeline was newly established. Results: First results showed a shift towards larger muscle fiber diameters of the stimulated side, compared to the unstimulated control side. Based on this, chronic electrical stimulation of the RLN can induce hypertrophy of the vocalis muscle even after a relatively short stimulation period of 29 days. Upcoming trials will focus on longer stimulation periods as well as more intense stimulation algorithms., Vocal fold paralysis is a pathological motion impairment of one vocal fold, mostly caused by laryngeal nerve damage. If the vocal fold does not reinnervate a flaccid paralysis occurs due to denervation of the vocalis muscle and its atrophy.1 Patients with unilateral vocal cord paralysis suffer from hoarse and weak voice since there is always a remaining glottic gap during phonation. Today’s standard treatment of unilateral paralysis includes surgical medialization through either injection augmentation or laryngoplastic framework surgery.2 We want to investigate whether it is possible to selectively stimulate the denervated muscle fibers of the vocalis without causing pain or excitation of sensory nerve fibers or activation of innervated muscles in the neck region. The goal is 1. a verivication of functionality for screening and 2. a strengthening and increase in total volume of the target muscle on order to improve voice quality in patients with unilateral paralysis. In combination with voice therapy also electrical stimulation of laryngeal muscles has alraedy been used in order to achieve hypertrophy.3 Furthermore research with functional electrical stimulation of patients with long time denervated limb muscles showed very promising results.4 The selective stimulation of denervated muscles has been investigated in rabbits with unilateral paresis of the recurrent laryngeal nerve. It could be shown that with triangular ramping and very long pulses (> 200ms) the afferent nerve fibers where not stimulated but only denervated muscle, with change in muscle fibers confirmed through histology.5,6 It is to be investigated if these findings can be repeated with surface electrodes positioned in the neck area and successful stimulation of the denervated vocalis muscle can be performed without causing pain and excessive contraction of neighboring neck muscles rendering treatment impossible. The optimal stimulation parameters for this application and ideal position of the surface electrodes have yet to be investigated., Facial nerve paralysis as a peripheral nerve injury results in neuromuscular atrophy. The symptoms include significant aesthetic, functional and often life-altering consequences. Several procedures such as Nerve Grafting, Facial Reanimation and Rehabilitation have been developed to treat functional and cosmetic aspects of this disease.[1] Nerve grafting is a sophisticated surgery, which requires experience but offers promising results. Although cable grafting is state of the art, the method suffers the disadvantage of long nerve regrowth time. [2]Facial Pacing systems too show promising results to treat facial paralysis. [3] [4] Former research showed good results stimulating denervated extremity muscles using FES.[5] Nevertheless this field of research is still lacking optimal stimulation settings to selectively recruit denervated atrophic or simply age-related atrophic facial muscles under non painful conditions. Methods: Several Devices are considered to investigate optimal stimulation settings. To encourage noninvasive screening methods for facial pacing, surface electrodes are used to estimate the optimal settings for stimulations. The use of surface electrodes causes the need for optimized electrode positioning, which is also investigated. Results: Martin et al. [6] showed that recruitment of denervated muscles requires exponentially shaped pulses with long phase durations(>200ms). The outcome of our investigation confirms these findings as well, showing best performance when recruiting paralyzed facial human muscles with biphasic long-duration impulses. It is crucial to position the surface electrodes appropriately in order to avoid stimulation of innervated muscles, for instance the masseter muscle. Conclusions: Surface electrodes, combined with the optimal stimulation settings, offer a screening possibility for facial pacing. Since muscles affected by age-related atrophy could be recruited too, further research is necessary to show effectiveness of training using the determined exponential patterns., Artificial stimulation of the vagus nerve, the main nerve of the parasympathetic nervous system, gained importance in the last years. Due to the modulatory interaction with the autonomous nervous system, the stimulation re-establishes the sympathovagal balance, counteracts over-inflammation responses or improves peripheral perfusion.1-3 Thus, the clinical applications have a wide range from depression to acute/chronic pain or cardiovascular dysfunction up to various neurological disorders.3-7 Neuromodulation is mediated via either implanted cervical, transcutaneous cervical/auricular or percutaneous auricular stimulation devices. While implanted stimulation devices are interrelated with high risks/costs and transcutaneous devices lack precision and require strong stimuli during their operation, percutaneous devices seem to avoid these drawbacks.8 Current percutaneous stimulators use needle electrodes in the auricle to stimulate afferent nerve fibers by the use of simple monophasic or biphasic stimulation patterns with the need for an additional reference electrode.5 No adaptation of the stimuli is possible to account for the specific pathology to be treated as well as the current physiological state of the patient.8 Our group has developed a multi-punctual percutaneous stimulator which operates three independent stimulation channels without any additional reference electrode.8 Stimulation patterns, with specific triphasic pulses, seem to reduce adaptation processes and to establish a pathology specific efficient stimulation. The pattern can be advantageously adapted throughout the stimulation duration to account for the current treatment state and physiological state of the patient [9]. Specific and precise positioning of needles - based on electrical and optical approaches10 - close to auricular nerves is performed, which is of high importance for efficient nerve stimulation. Preliminary studies of our group show positive effects of this percutaneous stimulation on heart rate variability, cerebral/peripheral blood perfusion, pain, sleep, diabetic food syndrome and cervical dystonia.1,6,8,9,11,12, Use of electrical stimulation (ES) of skeletal muscle as a tool to restore normal control of movement and ability to perform motor tasks has lately received increasing attention. Its capability to elicit muscle tissue contractions through the delivery of current impulses is commonly exploited in clinical settings,1 when damage to the nervous system, either central or peripheral, produces rapid denervation of muscle, resulting in weakness or paralysis. Possible mechanisms of muscle fibre recruitment have previously been studied using stereotyped electrical pulses delivered at variable pulse frequency, width and current amplitude.2 However, these protocols often exhibit several significant limitations, resulting in an overall decreased efficiency of contraction, ultimately leading to the development of muscular fatigue, as well as the elicitation of unpleasant symptoms. In the present study, the influence that different parameters of ES protocols exert on the efficacy of skeletal muscle cell contractions was investigated in skeletal myotubes in culture. The efficiency of a “noisy” stimulus waveform, derived from human muscle electromyogram (EMG) recordings, used as templates for the delivery of ES, was compared with conventional stereotyped 1 Hz and 40 Hz electrical stimulation delivery.3 EMG traces obtained by recording human gastrocnemius medialis muscle activity during sessions of real overground locomotion, were used to design the “noisy” stimulation pattern (EMGstim). ES protocol efficiency in inducing contractile activity of cultured skeletal muscle cells was compared by measuring intracellular Ca2+ dynamics and patch-clamp electrophysiological recordings. Collected data demonstrated that EMGstim was more efficient in inducing myotube cell action potential firing, [Ca2+]i changes and contractions, when compared with more conventional electrical stimulation using stereotyped rectangular pulses. Furthermore, it was demonstrated that EMGstim strength was also considerably lower than the minimum current amplitude required to induce contractions via canonical stimulation protocols. These results demonstrate the peculiar properties of the “noisy” EMGstim pattern to enhance the efficiency of muscle cell recruitment, minimizing charge transfer and therefore preventing possible tissue damage. We suggest this could represent a promising new approach for the optimization of ES protocols and for future design of electrical devices to stimulate the rehabilitation/recovery of weakened or injured muscles in human patients., Spinal cord injury is a traumatic injury of descending spinal cord tracts that alters the spinal neural circuitry.1-3 Spasticity is a common result of spinal cord injury (SCI) and can restrict daily living activities, cause pain and fatigue and, therefore, decrease the quality of life for SCI individuals.4-5 The aim of this study is to evaluate the effects of transcutaneous spinal cord stimulation (tSCS) on individuals with post-traumatic SCI for the alleviation of lower limb spasticity. Methods: In total, 8 subjects, 5 males and 3 females, aged between 31 – 63 years old (M = 49,9; SD = 11,5) were studied, with complete- and incomplete SCI. The evaluation of the effects of tSCS was done by means of electrophysiological evaluation and evaluation of residual motor control functions. The protocol consisted of four stages: first assessment/evaluation (control data), application of 30-min tSCS, a second assessment immediately after the treatment and a third assessment two hours after stimulation. The assessments consist of the evaluation of the spasticity level through the Ashworth scale, clonus beet quantification, 10-m walking test (if possible), electrophysiological evaluation (Brain Motor Control Assessment, BMCA [1]) and the Wartenberg pendulum test (WPT).6 Results: The index of spasticity R2n, derived from the WPT is the primary variable and the results of the WPT show increase in muscle tone in four subjects while the others presented average index values ≥ 1, indicating non-spastic conditions. During the BMCA, there was a significant difference of the normalized EMG activity of all muscles before the stimulation and immediately after stimulation for all participants, which indicates amelioration of intrinsic phasic and extrinsic spasticity. Enhancement of motor control was also observed. Conclusion: The similarity of the effects of tSCS with those induced by epidural SCS, strongly suggests that both techniques are able to activate similar neural structures. From our results we can see that the application of low-intensity tSCS for 30 minutes leads to the alleviation of lower limb spasticity regardless of the clinical profile of the subjects and enhancement of voluntary motor control in the motor incomplete SCI subjects., Whether via sarcopenia, cachexia, or sequela of trauma, the degeneration of muscle has been consistently identified as an independent risk factor for mortality.1 Many recent investigations have realized the quantitative potential of CT image analysis to describe skeletal muscle volume and quality.2-4 However, the optimum metric for assessing these data remains debated. Identifying a novel quantitative method for muscle assessment in this regard would allow for the generalizability of such studies to clinical practice and therefore aid in the indication of compensatory targets for clinical intervention. While there is much extant literature reporting the use of average HU values to investigate muscle quality and its utility as a comorbidity index, standardized methods for this analysis have yet to be defined, and no existing studies have explored the utility of an entire radiodensitometric distribution. Herein, we hypothesize that rigorously quantifying entire HU distributions can elicit much more information regarding muscle quality than extant methods that, to date, only utilize average HU attenuation values. This study reports the development and use of this method, wherein we assess upper leg muscle quality utilizing nonlinear trimodal regression analysis with radiodensitometric distributions from computed tomography (CT) scans of a healthy young adult, a healthy elderly subject, and a spinal cord injury patient exhibiting complete lower motor neuron denervation. Results from this assessment highlight the utility of entire HU attenuation value distributions and identify novel parameters from these analyses that could provide further insight into how muscle degeneration can be optimally quantified., Physical activity plays an important role in preventing muscle atrophy and chronic diseases in adults and the elderly. Voluntary physical exercise is not always feasible and other therapies should be applied such as electrical stimulation (ES).1 The process of calcium storage, uptake and release (EC-coupling) and, in a broader framework, Ca2+ cycling is essential in activity-induced muscle adaptation.2 De-codification of Ca signals is accomplished by an heterogeneous class of decoders such as transcription factors (i. e NFATc1, PGC1α) kinases (CaMks) and phosphatases (Calcineurin).3,4 We investigated the effects of either passive ES (acute or long-lasting) or voluntary physical exercise (leg press, LP), on expression of Ca2+ handling proteins of the sarcoplasmic reticulum and on the activation of key Ca2+ signal decoders in human vastus lateralis (VL) of elderly sedentary persons. Muscle sections and total homogenates were obtained from biopsies performed before and seven days after nine weeks of ES, before and 30 minutes after one session of ES and before and seven days after LP volitional exercise on a group of volunteers.1,5 Expression of Sarcalumenin, SERCA and p-CaMKII were evaluated by western blot while NFATc1/PGC1α nuclear translocation and muscle remodeling were determined by immunofluoresence. Evidence of kinase and phosphatase activation after both ES and LP were obtained. NFATc1 translocation to nuclei 30 minutes after one ES session training was obtained, after 9 weeks of ES NFATc1 translocation lasted at least 7 days. Moreover, mixed SERCA 2/MHCII fibers and Ca2+ handling proteins Sarcalumenin and SERCA 2 increased after ES. Conclusions. These results show that ES influences expression of muscle components deputed to Ca2+ cycling and promotes fiber remodeling essential to improve muscle performance in old sedentary people. This work identifies a set of molecules which are modifiable by ES, easy to measure and gender and age independent suitable as biomarkers for skeletal muscle response to neurorehabilitation., Most organisms experience changes in regenerative abilities through their lifespan. The principles that underlie the decline in regenerative abilities through lifespan are currently being unraveled. However, it is already clear that both cell-intrinsic (such as cellular senescence) as well as cell-extrinsic (such as alterations in the regenerative environment) factors play significant roles. During aging, numerous tissues exhibit a progressive decline in homeostasis and regeneration that results in tissue malfunction, pathology and degeneration. With age, both stem and progenitor cells undergo a series of alterations including loss of self-renewal capacities, altered proliferative activity, declines in functionality and potency. These changes have been shown to contribute to the dysfunction and degeneration of a number of tissues and systems including most epithelia and endothelia, blood, skeletal and cardiac muscle, bone, cartilage, the peripheral and central nervous system (CNS), and organs such as the pancreas, liver, kidney and lungs. The regenerative capacity in the skeletal muscle system experiences a marked decline with age in many organisms, as reflected by a decrease in the generation of muscle fibres and an increase in fibrotic tissue upon muscle injury. In humans, this is an underlying cause of sarcopenia, the loss of muscle mass that accompanies late aging. The decline in muscle regenerative potential is largely attributed to changes in satellite cells, the muscle stem cells, which undergo age-related declines in proliferative and myogenic capacities. Indeed, satellite cell numbers decline gradually in mammalian muscles with advancing age. Age-specific changes have also been reported for mesenchymal stem cells (MSCs), stromal cells that can differentiate into multiple cell types such as osteoblasts, chondrocytes, and adipocytes. Alterations include a loss in chondrogenic potential leading to impaired chondrocyte formation, which results in decreased cartilage repair in aged mammals. Furthermore, studies in human-derived bone marrow MSCs revealed age-dependent decreases in their capacity to differentiate to osteoblasts, which are related to increases in the level of MSCs senescence and apoptosis upon aging. Together, these alterations contribute to conditions such as osteoporosis and reduced bone repair capacity that are characteristic of human aging. A number of cellular and molecular mechanisms have been associated with the decline in regenerative abilities observed during aging in humans. These include intrinsic factors such as genomic instability (including telomere attrition), mitochondrial dysfunction, epigenetic changes, loss of proteostasis and metabolic alterations, as well as cell-extrinsic factors such as disruption of the regeneration niche and alterations in systemic signals. Though most of these factors can contribute to age-related impairment in regenerative capacity, a consensus on their relative importance in this process is currently lacking. Furthermore, emerging evidence suggests a high degree of interconnectivity between them, stressing the importance of identifying the common denominators. The advances in our understanding of the factors that modulate the decline in regenerative abilities have pinpointed areas of potential clinical relevance. In this view examining the influence of systemic factors on aged progenitor cells from tissues activated during neurorehabilitation training may prove to be clinically relevant. Our activity will be focused on the study of 3 different markers present in blood and tissue biopsies, such as long and small noncoding RNAs,1-3 growth factors,4-6 and transcription factors, such as NFAT.7,8