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Abstract: It has been revealed that skeletal muscle cells have the potential to generate, sense and respond to biomechanical signals and that, mechanical force is one of the important factors influencing proliferation, differentiation, regeneration and homeostasis of skeletal muscle cells and myoblasts. The aim of this study was to illustrate the effect of cyclic uniaxial strain on myogenic differentiation of adipose-derived stem cells (ASCs). This study was designed to investigate this effect within 3 days in 4 groups: control (untreated), chemical, chemical-mechanical and mechanical based on exposure of ASCs to chemical growth factors for 3 days or to mechanical strain just on the 2nd day. Finally, cell orientation, muscle-related gene expression, myosin protein synthesis and the number of myosin-positive cells were examined to estimate the rate of differentiation. By studying the cells before and after exposure to uniaxial strain, it could be observed that by exerting the load, the cells were organized almost perpendicularly to strain direction. Real-time RT-PCR demonstrated that uniaxial strain had a significant effect on up-regulation of muscle-related genes in chemical–mechanical group (P <0.001) as compared to mechanical or chemical groups. Immunocytochemistry confirmed the myosin-positive cells in treated groups and the numbers of these cells were enumerated by flow cytometry. These data suggest that uniaxial cyclic strain could affect ASCs and cause their myogenic differentiation and that the combination of chemical myogenic differentiation factors with mechanical signals promotes differentiation much more than differentiation by chemical myogenic differentiation factors or mechanical signals alone. [Copyright &y& Elsevier]

[Display omitted] • Transplantation of DPSCs improved motor skills and muscle activity in rat brain lesion. • Transplantation of DPSCs prevented the atrophy of the striatum. • Transplantation of DPSCs impeded gliosis and microgliosis in rats. • Transplantation of DPSC downregulated Caspase-3 in brain lesion. • Transplantation of DPSCs decreased the expression of inflammatory cytokines, TNF and IL-1β, at mRNA level. Stem cell-based therapy has recently offered a promising alternative for the remedy of neurodegenerative disorders like Huntington's disease (HD). Herein, we investigated the potential ameliorative effects of implantation of dental pulp stem cells (DPSCs) in 3-nitropropionic acid (3-NP) rat models of HD. In this regard, human DPSCs were isolated, culture-expanded and implanted in rats lesioned with 3-NP. Post-transplantation examinations revealed that DPSCs were able to survive and augment motor skills and muscle activity. Histological analysis showed DPSCs treatment hampered the shrinkage of the striatum along with the inhibition of gliosis and microgliosis in the striatum of 3-NP rat models. We also detected the downregulation of Caspase-3 and pro-inflammatory cytokines such as TNF and IL-1β upon DPSCs grafting. Overall, these findings imply that the grafting of DPSCs could repair motor-skill impairment and induce neurogenesis, probably through the secretion of neurotrophic factors and the modulation of neuroinflammatory response in HD animal models. [ABSTRACT FROM AUTHOR]

Highlights • Grafted Sertoli cells (SCs) exhibited a decline in apoptosis in a rat model of amyloid beta toxicity. • Implantation of SCs in rats with Aβ1-42 receiving vehicle decreased the amount of gliosis. • We found that implanted SCs can recover hippocampus dependent memory and learning. • Transplanted SCs restored long-term synaptic plasticity in lesioned rats. Abstract Alzheimer's disease (AD) is a degenerative nerve disease which adversely affects memory and learning skills. Currently, there is no disease-modifying therapeutic approach for AD. However, a growing body of literature suggests cell based therapies as a promising remedy for neurological disorders. Among the potential cell sources, testis- derived Sertoli cells (SCs) appear to be an attractive choice due to their immune-privileged capacities. Herein, we investigated the neuro-restorative/protective effects of SC transplants in a rat model of amyloid beta toxicity. To this end, GATA-4 and vimentin positive SCs were transplanted into rats with amyloid beta induced hippocampal lesions. According to our in vivo results, implanted SCs survived, exhibited reduction in both apoptosis as well as astrocytic migration. Additionally, transplantation of SCs restored hippocampus dependent memory and learning, along with the recovery of long-term synaptic plasticity. Taken together, these data indicate that SCs are a valuable source for cell-based therapies particularly aimed at AD. [ABSTRACT FROM AUTHOR]

Abstract: The hippocampus is essentially involved in learning and memory, and is known to be a target for androgen actions. As neuron–astrocyte interactions play a crucial role during development and in the adult brain, it is thought that astrocytes support learning and memory through specific mechanisms. In this study, the effect of testosterone-induced impairment of acquisition and retrieval of long-term memory, on the number of astrocytes was studied. Adult male albino Wistar rats were bilaterally cannulated into the CA1 region and received 80μg/0.5μl of testosterone enanthate dissolved in DMSO as vehicle. In trained groups injection was done 30min before training. Our results showed that pre-training administration of testosterone increased escape latency and the traveled distance, as compared to intact or DMSO administered (sham-operated) counterparts. Testosterone administration also increased the number of astrocytes in rats, compared to sham-operated and intact animals in both trained and non-trained groups. We have also found that spatial learning could increase the number of astrocytes in the hippocampus as a center of long-term learning and memory and recall. It is concluded that, testosterone-induced impairment in learning and memory, causes an increase in the number of astrocytes in the CA1 region of rat hippocampus. [Copyright &y& Elsevier]

• THC administration interrupts long term memory and long term potentiation. • Stereological studies revealed considerable atrophy in hippocampus. • Several signaling cascades related to synaptic regulation were interrupted in hippocampus under THC administration. Tetrahydrocannabinol (THC), a major psychoactive constituent of marijuana, can substantially change the function of several brain areas, leading to behavioral impairment including memory and learning dysfunction. Given the importance of hippocampus as one of the chief parts of the brain involved in memory processing, the present study seeks to investigate structural and histological alterations in hippocampus as well as behavioral defects provoked by THC treatment. Besides, using genome-wide sequencing, we adopted a pathway-based approach to discover dysregulated molecular pathways. Our results demonstrated remarkable hippocampal atrophy, and also interrupted memory function and long term potentiation (LTP) under THC exposure. We also detected several dysregulated signaling pathways involved in synaptic plasticity as well as cell-cell interaction in the hippocampus of THC-treated rats. Overall, the results indicate a potential correlation between disrupted signaling cascades, hippocampal atrophy and memory defects caused by THC treatment. [ABSTRACT FROM AUTHOR]

Recent evidences showed that, noise stress causes abnormal changes in structure and function of central nervous system (CNS). The Current study was conducted to evaluate some stereological parameters of the medial prefrontal cortex (mPFC) of male pups of Wistar rat after prenatal and early postnatal noise stress. 18 pregnant Wistar rats were randomly divided into prenatal noise-exposed (NE) group, postnatal NE group, and controls. Male pups of NE groups were exposed to noise 100 dB at the frequency ranges of 500–8000 Hz, 4 h per day from gestational day one (GD1) to GD21 for the prenatal NE group, and from postnatal day one (PND1) to PND21 in the postnatal NE group. The Control group animals were maintained under standard condition without noise stimulation. Corticosterone level in plasma was measured using ELISA technique. Changes of the neurons and non-neurons cells number and volume of the mPFC were evaluated by stereological analysis. Tunnel assay was also used for detection of apoptotic cells. Increase in plasma corticosterone level, decrease in the number of neurons, and increase in the apoptotic cells number were observed in both NE groups. Decrease in volume of mPFC and also in non-neurons cells number was observed in the prenatal NE group. An increase in the non-neurons number was seen in the postnatal NE group. Data of the current comparative study showed that, noise stress during prenatal and early postnatal periods can induce the abnormal alteration in some stereological parameters of mPFC in male pups of Wistar rat. These negative alterations were more remarkable after prenatal noise stress. [ABSTRACT FROM AUTHOR]

•.Alpha Lipoic Acid has a protective effect on brain cells. • THIM has a toxic effect on the developing brain. • Alpha Lipoic Acid decreaces the glutathione content of prefrontal cortex. • ALA is one of the important antioxidants that can prevent the adverse effects of THIM-containing products. Thimerosal (THIM) is a common preservative used in many pharmaceutical drugs, vaccines, cosmetics and many other products. Today, it was somewhat clear that Thimerosal (THIM) is a neurotoxicant preservative. We aimed to use of a suitable agent for preventing of THIM side effects on brain. Therefore, in this research, the protective effects of Alpha Lipoic Acid (ALA), against THIM-induced brain cell loss, changes in neuroimmune cell and enzymatically contents were examined. Male Wistar rats (n = 60) were randomly distributed into five groups: 1- THIM group; this group received THIM at dose of 300 μg /kg on 7, 9, 11, 15 days after birth 2- ALA group; received ALA (20 mg/kg) in the same order. 3- THIM & ALA group; this group received ALA in the same dose, 30 min before THIM administration.4& 5; Saline and ALA vehicle groups were also included. At 56th postnatal day, samples of the prefrontal cortex were collected and prepared for stereological, immune-histochemical, and enzymatic evaluations. The result showed that ALA, prevents the adverse effects of THIM on brain cell loss, abnormal changes in neuroimmune cells (p < 0.05), prefrontal cortex volume (p < 0.05), and the glutathione content of prefrontal cortex (p < 0.05). In conclusion, neonatal exposure to THIM can induce abnormal alterations in neuroimmune cells and brain cell density as well as prefrontal cortex volume & glutathione content, and ALA can ameliorate these abnormalities. [ABSTRACT FROM AUTHOR]

Melatonin is primarily secreted by the pineal gland in dark. In addition to its role as an internal sleep facilitator, melatonin acts as an antioxidant, anti-inflammatory and neuroprotective agents. melatonin has been introduced as a therapeutic strategy for sleep disorders. Hence, in the present study, we studied the neuroprotective effects of pre- and post-treatment of melatonin in locus coeruleus nucleus (LC) of rapid eye movement (REM) sleep deprived (REM-SD) male adult rats. Adult male rats of control, sham and trial groups were used Exogenous melatonin (ExMe) was intraperitoneally injected in two forms of pre and post treatment. The protein level of cleaved caspase-3, the number and density of tyrosine hydroxylase (TH) positive neurons and the microglia population in LC were studied by western blot and immunohistochemistry respectively. Morphological changes of LC nucleus and its neurons were also studied by using stereological analysis. The number of neurons and volume of LC was reserved in animals that had received post-RSD ExMe. Apoptosis significantly was decreased comparing to RSD and Pre-RSD animals. Melatonin post-treatment of RSD rats also decreased cleavage of caspase-3 and increased reduced glutathione content in LC. Moreover, immunohistochemistry analysis showed an increase in the number of TH positive neurons and a decrease in microglia migration. Based on our findings antioxidant properties of exogenous melatonin could play a critical role in certain types of sleep disorders. [ABSTRACT FROM AUTHOR]