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Background and Objective: Neurotrophic factors are diffusible polypeptides that have critical roles in survival, proliferation and differentiation of stem cells. This study was done to assess the role of neurotrophic factors (CNTF‎, BDNF, ‎GDN‎F, ‎NT-‎3‎) expression and proliferation rate of neural stem cells (NSCs) in coculture with mesenchymal stem cells (MSCs). Materials and Methods: In this experimental study, NSCs and MSCs were isolated from adult Wistar rat. Initially, NSCs was harvested from temporal lobe after mechanical digestion by a sterile flamed Pasteur pipette and enzymatic digestion with trypsin and Dnase. The cell suspension was cultivated in a flask with DMEM/F12 medium supplemented with 10% FBS 100U/ml Penicillin and 100 mg/ml Streptomycin. To obtain MSCs, bone marrow of femur and tibia bones were flashed out and cultured. MSCs and NSCs‎ cocultured by transwell ‎system in DMEM/F12 medium supplemented with 10% FBS 100U/ml Penicillin and 100 mg/ml Streptomycin. Haemocytometer, immunocytochemistry and RT-PCR methods were performed to identify and evaluate cell proliferation, purity levels and neurotrophic factors expression. Results: There ‎is‎ no differences in NTFs profile of ‎neurotrophic‎ factors expression between ‎coculture ‎group‎ ‎and‎ control ‎NSCs, but interactions between MSCs and NSCs significantly promoted NSCs proliferation (P<0.05). Conclusion: This study showed that coculture of NSCs with MSCs might be prfered in cell-therapy than‎ NSCs.‎

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Background and Objective: Research have been focused on the applying the chemical inducer for trans-differentiation the adult BMSCs into neural cell. So that, at the first should investigate the toxcity effect of the chemical inducer on the induced cells. Plasticity and easy accessibility of bone marrow mesenchymal stem cells is a unique charactristic for treatment of neural disorderies. This study was desgined to determine the inductive effect of Deprenyl and Dimethyl sulfoxide on proliferation and survival of the mesenchymal stem cells. Materials and Methods: In this experimental study, BMSCs isolated from the adult rat bone marrow and cultured in αMEM containing 10% FBS. Cell identity for surface antigens was performed in third passage by immunocytochemistry and multipotancy capacity of BMSCs was done by BMSC differentiation into adipocytes and osteocytes. The cells were exposed to chemical agents (a: the αMEM medium supplemented with 2% DMSO, b: the αMEM medium supplemented with 10^-8M Deprenyl) for 24 houres and then transferred to αMEM containing 10% FBS cell survival and proliferation was evaluated after the 24, 48, 72 and 96 houres by MTT [3-(4-5-Dimethylthiazolyl-2-y1)-2,5-diphenyltetrazolium bromid] test. Data were analyzed using SPSS-16, One-Way ANOVA and Tukey tests. Results: In addition to expression the surface antigens and adipogenic and osteogenic differentiation by BMSCs, MTT test results showed that proliferation and survival of induced-deprenyl and DMSO cells within 48, 72 and 96 hours after the induction was increased significantly than negative control group. Conclusion: Deprenyl increases survival and cell proliferation compared to Dimethyl Sulfoxide. It can be used as cell inducer.

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Background and Objective: Epidermis is the outer layer of skin, regenerating continuously. Epidermal stem cells play important roles in tissue regeneration, scar regeneration and neoplasm formation.This study was displayed for the isolation and culture of interfollicular epidermal stem cells from newborn mouse skin without feeder layer. Materials and Methods: This experimental study was displayed on 0-3 old-day newborn NMRI mouse skin 60-70 gr weight. The epidermal keratinocytes were separated mechanically and enzymatically from 0-3 old day newborn mice skin (NMRI strain) and seeded on fibronectin-collagen culture substrates. Putative epidermal stem cells were selected by rapid adherence for 10 minutes on this composite matrix of type 1 collagen and fibronectin and the unattached cells were discarded and attached cells were cultured in essential minimal eagle medium (EMEM) (ca+2-free culture medium containing 0.05 mM Ca+2, 9% FBS, 50% conditioned medium, EGF (epidermal growth factor) and Cholera Toxin. The immunocytochemistry of β1-integrin analysis used to indicate their stemness nature. Results: The results indicated that rapid adherence yields 50% purity. By using this method, the stem cells have been subcultured continuously without any change in the cell properties. The isolated interfollicular epidermal stem cells, expressed epidermal stem cells special marker (β1-integrin) in high levels, which indicates stem cell nature. Conclusion: This new method yields pure viable epidermal stem cells that can be used in regenerative medicine and cell therapy.

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Background and Objective: Degeneration of neurons in the central nervous system occurs during aging. Transplantation of neural stem cells (NSCs) can be preventing the degeneration of neurons. In addition to neuronal replacement, with the production of neurotrophic factors, increased survival and proliferation of endogenous cells. This study was done to compare the cell proliferation, neurotrophic factors expression and features of NSCs harvested from different areas of the central nervous system in vitro. Materials and Methods: In this laboratory study NSCs have been harvested from subgranular zone (SGZ), subventricular zone (SVZ) and central canal of spinal cord from adult Wistar rats with mechanical, enzymatical digestion and subsequently was cultured in α-MEM medium supplemented with serum as monolayer or adherent conditions and passaged for 13 times. Immunocytochemistry was used to determine expression of the nestin and GFAP markers. Semi-quantitative RT–PCR was used to confirm genes expression (NGF, CNTF, NT3, NT4/5, GDNF and BDNF). Results: Morphological features of stem cells extracted from different regions of the central nervous system were similar in the culture. Doubling time NSCs in the SVZ (37.45 hr) is shorter than in the SGZ (44.04 hr) and central canal of spinal cord (57.22 hr). The culture conditions as well as monolayer neural stem cells are capable of producing neurospheres. Also, nestin and GFAP markers, expressed by NSCs. Neurotrophic gene expression pattern profiles were similar to each other in stem cells extracted from the SGZ, SVZ and central canal of spinal cord. Conclusion: Neurotrophic gene expression in stem cells extracted from different regions of the central nervous system were similar, but proliferation capacity was higher in NSCs, which have been harvested from the SVZ.

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Background and Objective: Adult neurogenesis occurs in most mammalian species in two main areas of brain: 1- subventricular zone 2- the dentate gyrus of the hippocampus. Many factors such as 17-B estradiol affect neurogenesis in the hippocampus. The aim of this study was to investigate the effect of exogenous 17-B estradiol on neurogenesis and astrocyte functions in the ovariectomized mice.
Methods: In this experimental study; NMRI mice were allocated into five experimental groups including Sham, Control, Treatment with single dose of 17-B estradiol two weeks after ovariectomy (OVX) and were sacrificed 24 hours later, Treatment with single dose of 17-B estradiol two weeks after Ovx and were sacrificed 48 hours later and   Treatment with single dose of Seasame Oil 2 weeks after OVX and were sacrificed after 24 hours. Animals were transcardially perfused with paraformaldehyde. Brains were removed and its sections for cresyl fast violet staining and GFAP immunohistochemistry were prepared. Cells were counted and investigated.
Results: Neuronal density and Proliferation of hippocampal progenitor cells in the CA1 region of 17-B estradiol treated mice significantly increased up to 24 hours (P<0.05). Density of glia and particularly astrocytes in different regions of the hippocampus significantly reduced after treatment with 17-B estradiol (P<0.05).
Conclusion: Density of hippocampal CA1 neurons are influenced by 17-B estradiol. Also, density and morphology of glia cells, especially astrocytes in different regions of the hippocampus are affected by 17-B estradiol.

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Background and Objective: Neurogenesis is the process through which neurons are generated from neural stem cells. This process has been shown to occur in special zones of the adult brain including the subventricular zone (SVZ) of the lateral ventricles and the dentate gyrus of the hippocampus. Gonadal steroids affect different steps of neurogenesis, and cell proliferation seems to be increased by estrogens. This study aimed to investigate the neurogenic changes in the SVZ at different phases of the estrous cycle.
Methods: In this experimental study, 26 NMRI mice were used. The mice were identified by vaginal smear and then divided into 4 groups including proestrus (n=5), estrous (n=7), metestrus (n=7) and diestrous (n=7). Different stages of the estrous cycle were determined by staining vaginal smears. Also, the qualitative assessment of cell proliferation in the SVZ was performed by cresyl fast violet staining and glial fibrillary acidic protein (GFAP) immunohistochemistry at different stages of the estrous cycle.
Results: In microscopic sections stained with cresyl violet, it was observed that cell density in the proestrus stage of the estrous cycle was greater than in any other stages of the estrous cycle. A comparison of sections stained with anti-GFAP showed that the density of astrocytes in proestrus was significantly higher than in other groups.
Conclusion: Proestrus stage of the estrous cycle is associated with increased cell proliferation and density of astrocytes in the SVZ of mice. Neurogenesis is correlated to changes in sex hormonal levels at different phases of the estrus cycle.