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Spinal muscular atrophy (SMA) is a severe neuromuscular disease affecting children, due to mutation/deletion of survival motor neuron 1 (SMN1) gene. The lack of functional protein SMN determines motor neuron (MN) degeneration and skeletal muscle atrophy, leading to premature death due to respiratory failure. Nowadays, the Food and Drug Administration approved the administration of three drugs, aiming at increasing the SMN production: although assuring noteworthy results, all these therapies show some non-negligible limitations, making essential the identification of alternative/synergistic therapeutic strategies. To offer a valuable in vitro experimental model for easily performing preliminary screenings of alternative promising treatments, we optimized an organotypic spinal cord culture (derived from murine spinal cord slices), which well recapitulates the pathogenetic features of SMA. Then, to validate the model, we tested the effects of human Mesenchymal Stem Cells (hMSCs) or murine C2C12 cells (a mouse skeletal myoblast cell line) conditioned media: 1/3 of conditioned medium (obtained from either hMSCs or C2C12 cells) was added to the conventional medium of the organotypic culture and maintained for 7 days. Then the slices were fixed and immunoreacted to evaluate the MN survival. In particular we observed that the C2C12 and hMSCs conditioned media positively influenced the MN soma size and the axonal length respectively, without modulating the glial activation. These data suggest that trophic factors released by MSCs or muscular cells can exert beneficial effects, by acting on different targets, and confirm the reliability of the model. Overall, we propose the organotypic spinal cord culture as an excellent tool to preliminarily screen molecules and drugs before moving to in vivo models, in this way partly reducing the use of animals and the costs.

We present a shape processing framework for visual exploration of cellular nuclear envelopes extracted from histology images. The framework is based on a novel shape descriptor of closed contours relying on a geodesically uniform resampling of discrete curves to allow for discrete differential-geometry-based computation of unsigned curvature at vertices and edges. Our descriptor is, by design, invariant under translation, rotation and parameterization. Moreover, it additionally offers the option for uniform-scale-invariance. The optional scale-invariance is achieved by scaling features to z-scores, while invariance under parameterization shifts is achieved by using elliptic Fourier analysis (EFA) on the resulting curvature vectors. These invariant shape descriptors provide an embedding into a fixed-dimensional feature space that can be utilized for various applications: (i) as input features for deep and shallow learning techniques; (ii) as input for dimension reduction schemes for providing a visual reference for clustering collection of shapes. The capabilities of the proposed framework are demonstrated in the context of visual analysis and unsupervised classification of histology images., Eurographics Workshop on Visual Computing for Biology and Medicine, Joint Session DAGM GCPR - VMV - VCBM, 61, 70, Marco Agus, Khaled Al-Thelaya, Corrado Cali, Marina M. Boido, Yin Yang, Giovanni Pintore, Enrico Gobbetti, and Jens Schneider, CCS Concepts: Applied computing --> Imaging; Computing methodologies --> Shape representations; Cluster analysis

TLQP peptides (TLQPp) act on synaptic strengthening or against neuronal apoptosis but their involvement in Amyotrophic Lateral Sclerosis (ALS) is not well known. We used an ALS animal model (SOD1-G93A) and human tissues (plasma and fibroblasts from both patients and controls), to address the TLQPp expression and their modulation in ALS mechanisms. Mouse motor neuronal cells (NSC-34), were used to study the neuroprotective role of the TLQP-21 against oxidative stress induced by Sodium Arsenite. TLQPp were immunoquantified by ELISA, their cell expression studied by immunofluorescence while cell viability was addressed by MTT assay. In the NSC-34 naïve cells, TLQPp were found within the cytoplasm, axons and growth cones. Upon stress, they appeared immunolocalized exclusively within a cytoplasmatic area, close to the nucleus, (probably the Golgi). Moreover, under stress, TLQPp levels were reduced (42%, p=3.1x10-6), while the exogenous increase of TLQP-21 improved cell viability (13%, p= 0.018). In naïve fibroblasts, TLQPp were also similarly localized in an area, likely the Golgi, of patients and controls while their reduction (31%, p=0.03) was observed in cells with TARDBP-A382T mutation. Stress granules only appeared after SA treatment, and did not contain TLQPp. In plasma, a reduced release of TLQPp was associated with the beginning of the clinical motor symptoms in patients (12%, p=0.026), and with a pre-symptomatic stage in mutant mice (26.3%, p=0.048). Finally, in mouse spinal cord we identified by vescicular acetylcholine transporter (VAChT) antibody, a specific localization of the TLQPp in the motor neurons with a reduction in the pre-symptomatic stage of mutant mice. In conclusion, TLQPp are reduced in the stressed NSC-34 cells, mutant mouse motor neurons as well as in fibroblasts with TARDBP-A382T mutation that also induces production of reactive oxygen specie. Hence, we suggest that their reduction may occur in response to oxidative stress. They could be also considered as early biomarkers, while TLQP-21 acts as neuroprotective factor., Italian Journal of Anatomy and Embryology, Vol. 122, No. 1 (Supplement) 2017

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease leading to motor impairment, muscle atrophy and premature death caused by motoneuron degeneration. It is caused by the deletion/mutation of the telomeric survival motoneuron gene (SMN1), whereas the number of copies of the centromeric gene SMN2, which produces reduced levels of functional protein, is inversely proportional to the severity of disease (from severe to mild). However, the causes of selective motoneuron death still remain elusive. To clarify the time course and the mechanisms of motoneuron (MN) death, we investigated the SMNdelta7 murine model of SMA II (the intermediate SMA form), in which motor dysfunction leads to death at P13. We collected brains and spinal cords from SMA II and wild type embryos/pups at E19, P4, P9 and P13 for neuron counts and immunohistochemistry. Newborns underwent a battery of motor tasks and were assessed daily for body weight and survival. In ChAT-immunoreacted and Nissl-stained spinal sections, stereological counts reported a dramatic reduction in the number of lower (cervical) MNs (almost 40% at P13) in the SMA II mice; in particular MNs innervating proximal muscles seemed the most affected. In addition, we noticed an increased ChAT expression through time, making ChAT-MN count less reliable than Nissl-ones. Moreover, even though most studies mainly report death of lower motoneurons, stereological counts in the motor cortex revealed a specific decrease of layer V cortical pyramidal neurons in SMA II mice compared to WT. Also the corpus callosum thickness appeared halved in the P9 SMA II mice. Finally, immunohistochemistry against cleaved Caspase-3 and LC-3 suggested an involvement of the apoptotic and autophagic modes of cell death, respectively. Therefore, at least in the animal model, SMA affects both upper and lower motoneurons, and SMN1 role in neuronal development and survival should be further investigated. Targeting apoptotic and autophagic pathways can delay the disease progression, as we are currently showing in other studies., Italian Journal of Anatomy and Embryology, Vol 117, No 2 (Supplement) 2012

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects both lower and upper motor neurons (MNs) in the central nervous system. ALS etiology is highly multifactorial and multifarious, and an effective treatment is still lacking. Neuroinflammation is a hallmark of ALS and could be targeted to develop new therapeutic approaches. Interestingly, the transcription factor Nurr1 has been demonstrated to have an important role in the inflammatory process in several neurological disorders, such as Parkinson's disease and multiple sclerosis. In the present paper, we demonstrate for the first time that Nurr1 expression levels are upregulated in the peripheral blood of ALS patients. Moreover, we investigated Nurr1 function in the SOD1-G93A mouse model of ALS. Nurr1 was strongly upregulated in the spinal cord during the asymptomatic and early symptomatic phases of the disease, where it promoted the expression of brain-derived neurotrophic factor mRNA and the repression of NFκB pro-inflammatory targets, such as inducible nitric oxide synthase. Therefore, we hypothesize that Nurr1 is activated in an early phase of the disease as a protective endogenous anti-inflammatory mechanism, although not sufficient to reverse disease progression. On the basis of these observations, Nurr1 could represent a potential biomarker for ALS and a promising target for future therapies., Summary: We hypothesize that the transcription factor Nurr1 is activated in the early phase of the neurodegenerative disease amylotrophic lateral sclerosis (ALS), probably as a neuroprotective endogenous mechanism. Nurr1 might represent a promising target for ALS therapy.

Spinal muscular atrophy (SMA) is a pediatric genetic disease, characterized by motor neuron (MN) death, leading to progressive muscle weakness, respiratory failure, and, in the most severe cases, to death. Abnormalities at the neuromuscular junction (NMJ) have been reported in SMA, including neurofilament (NF) accumulation at presynaptic terminals, immature and smaller than normal endplates, reduced transmitter release, and, finally, muscle denervation. Here we have studied the role of agrin in SMAΔ7 mice, the experimental model of SMAII. We observed a 50% reduction in agrin expression levels in quadriceps of P10 SMA mice compared to age-matched WT controls. To counteract such condition, we treated SMA mice from birth onwards with therapeutic agrin biological NT-1654, an active splice variant of agrin retaining synaptogenic properties, which is also resistant to proteolytic cleavage by neurotrypsin. Mice were analyzed for behavior, muscle and NMJ histology, and survival. Motor behavior was significantly improved and survival was extended by treatment of SMA mice with NT-1654. At P10, H/E-stained sections of the quadriceps, a proximal muscle early involved in SMA, showed that NT-1654 treatment strongly prevented the size decrease of muscle fibers. Studies of NMJ morphology on whole-mount diaphragm preparations revealed that NT-1654-treated SMA mice had more mature NMJs and reduced NF accumulation, compared to vehicle-treated SMA mice. We conclude that increasing agrin function in SMA has beneficial outcomes on muscle fibers and NMJs as the agrin biological NT-1654 restores the crosstalk between muscle and MNs, delaying muscular atrophy, improving motor performance and extending survival.

Spinal muscular atrophy (SMA) is a recessive autosomal neuromuscular disease, due to homozygous mutations or deletions in the telomeric survival motoneuron gene 1 (SMN1). SMA is characterized by motor impairment, muscle atrophy, and premature death following motor neuron (MN) degeneration. Emerging evidence suggests that dysregulation of autophagy contributes to MN degeneration. We here investigated the role of autophagy in the SMNdelta7 mouse model of SMA II (intermediate form of the disease) which leads to motor impairment by postnatal day 5 (P5) and to death by P13. We first showed by immunoblots that Beclin 1 and LC3-II expression levels increased in the lumbar spinal cord of the SMA pups. Electron microscopy and immunofluorescence studies confirmed that autophagic markers were enhanced in the ventral horn of SMA pups. To clarify the role of autophagy, we administered intracerebroventricularly (at P3) either an autophagy inhibitor (3-methyladenine, 3-MA), or an autophagy inducer (rapamycin) in SMA pups. Motor behavior was assessed daily with different tests: tail suspension, righting reflex, and hindlimb suspension tests. 3-MA significantly improved motor performance, extended the lifespan, and delayed MN death in lumbar spinal cord (10372.36 ± 2716 MNs) compared to control-group (5148.38 ± 94 MNs). Inhibition of autophagy by 3-MA suppressed autophagosome formation, reduced the apoptotic activation (cleaved caspase-3 and Bcl2) and the appearance of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive neurons, underlining that apoptosis and autophagy pathways are intricately intertwined. Therefore, autophagy is likely involved in MN death in SMA II, suggesting that it might represent a promising target for delaying the progression of SMA in humans as well. The project was supported by grants of the Associazione Girotondo Onlus (Trivero, Italy), the Smarathon Association (Milan, Italy), and by a grant of the Italian Ministry of Health (Project RF-2009-1475235). AP was the recipient of a fellowship (3 years) from the ‘’Master and Back” project 2009 by the Regione Autonoma della Sardegna (Cagliari, Italy).

Spinal muscular atrophy (SMA) is a severe neuromuscular disease, the most common in infancy, and the third one among young people under 18 years. The major pathological landmark of SMA is a selective degeneration of lower motor neurons, resulting in progressive skeletal muscle denervation, atrophy, and paralysis. Recently, it has been shown that specific or general changes in the activity of ribonucleoprotein containing micro RNAs (miRNAs) play a role in the development of SMA. Additionally miRNA-206 has been shown to be required for efficient regeneration of neuromuscular synapses after acute nerve injury in an ALS mouse model. Therefore, we correlated the morphology and the architecture of the neuromuscular junctions (NMJs) of quadriceps, a muscle affected in the early stage of the disease, with the expression levels of miRNA-206 in a mouse model of intermediate SMA (SMAII), one of the most frequently used experimental model. Our results showed a decrease in the percentage of type II fibers, an increase in atrophic muscle fibers and a remarkable accumulation of neurofilament (NF) in the pre-synaptic terminal of the NMJs in the quadriceps of SMAII mice. Furthermore, molecular investigation showed a direct link between miRNA-206-HDAC4-FGFBP1, and in particular, a strong up-regulation of this pathway in the late phase of the disease. We propose that miRNA-206 is activated as survival endogenous mechanism, although not sufficient to rescue the integrity of motor neurons. We speculate that early modulation of miRNA-206 expression might delay SMA neurodegenerative pathway and that miRNA-206 could be an innovative, still relatively unexplored, therapeutic target for SMA.

Background aims Mesenchymal stromal cells (MSCs), after intraparenchymal, intrathecal and endovenous administration, have been previously tested for cell therapy in amyotrophic lateral sclerosis in the SOD1 (superoxide dismutase 1) mouse. However, every administration route has specific pros and cons. Methods We administrated human MSCs (hMSCs) in the cisterna lumbaris, which is easily accessible and could be used in outpatient surgery, in the SOD1 G93A mouse, at the earliest onset of symptoms. Control animals received saline injections. Motor behavior was checked starting from 2 months of age until the mice were killed. Animals were killed 2 weeks after transplantation; lumbar motoneurons were stereologically counted, astrocytes and microglia were analyzed and quantified after immunohistochemistry and cytokine expression was assayed by means of real-time polymerase chain reaction. Results We provide evidence that this route of administration can exert strongly positive effects. Motoneuron death and motor decay were delayed, astrogliosis was reduced and microglial activation was modulated. In addition, hMSC transplantation prevented the downregulation of the anti-inflammatory interleukin-10, as well as that of vascular endothelial growth factor observed in saline-treated transgenic mice compared with wild type, and resulted in a dramatic increase in the expression of the anti-inflammatory interleukin-13. Conclusions Our results suggest that hMSCs, when intracisternally administered, can exert their paracrine potential, influencing the inflammatory response of the host.

Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients.