Iranian

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Background: Bone marrow stromal cells (BMSC) are used as a source for cell therapy in different model for neurological disorder such as stroke and spinal cord injury. However, the transdifferentiation of BMSC into cholinergic phenotype requires more investigation. Methods: BMSC were isolated from adult rats, pre-induced with β-mercaptoethanol (BME) and followed by nerve growth factor (NGF) induction. Neurofilaments of 68 kDa, 160 kDa and 200 kDa (NF-200, NF-160 and NF-68, respectively) immuno-staining were used for evaluating the transdifferentiation of BMSC into neuronal phenotype. The percentage of neurofilaments immuno-reactive cells was applied in order to evaluate the results at the pre-induction and the induction stages. Also, NeuroD and Oct-4 expressions, using RT-PCR, were used in assessing the progression of BMSC into neuronal lineage. Choline acetyltransferase immuno-reactive cells were used for estimating the percentage of cholinergic neuronal phenotype. Immuno-staining with anti-microtubule-associated protein-2 (MAP-2) and anti-synapsin-I antibodies was done in order to evaluate cell tendency for synaptogenesis. Results: The yield of cholinergic neurons with BME as pre-inducer and NGF as inducer was 80%. Also, NF-200, NF-160, NF-68, MAP-2 and synapsin-I were detected in the transdifferentiated cells. RT-PCR showed the expression of NeuroD, while Oct-4 was not detected. Conclusion: BME as pre-inducer and NGF as inducer for BMSC transdifferentiation into cholinergic phenotype are potential sources in traumatic injury therapy in the central nervous system.

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Background: Cell therapy of many neurodegenerative diseases using bone marrow stromal cells (BMSC) requires the differentiation of BMSC into neuronal subtype. However, the transdifferentiation of BMSC into GABAergic phenotype requires more investigation. Methods: In this study, BMSC of adult female rats were pre-induced into neuroblast-like cells using 1 mM β-mercaptoethanol (βME) and 10 M retinoic acid (RA), followed by 40 mM potassium chloride as inducer. The BMSC were evaluated by fibronectin as well as Oct-4. The percentage of nestin, neurofilaments (NF 68, NF 160, and NF 200) and GABA immuno-reactive cells was used to evaluate the GABAergic differentiation at the pre-induction and induction stages. The statistical analysis was carried out using unpaired student's t-test and ANOVA with Tukey's multiple comparison. Results: The BMSC in the fourth passage expressed fibronectin up to 91.24 ± 0.82%. The pre-induced cells after 2 days of RA exposure showed the expression of neuroblastic markers of nestin and NF68 (81.56 ± 2.64% and 82.12 ± 2.65%, respectively). The yield of GABAergic neurons with β-ME for 1 h and RA as pre-inducer for 2 days followed by potassium chloride as inducer (40 mM for 3 days) was 60.64% ± 1.97%. In addition, NF160 and NF200 were detected in the transdifferentiated cells. RT-PCR showed no expression of Oct-4 after the induction and pre-induction stages. Conclusion: GABAergic-like neurons obtained from BMSC can be potentially used in cell transplanting for some neurodegenerative disorders.

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Background: Zinc (Zn) as an important trace element is essential for testicular development and spermatogenesis. Molecular mechanism of Zn action in the reproductive system may be related to metal binding low-molecular weight proteins, metallothioneins (MT). Our objective was to determine the effect of Zn on two important isoforms of MT, MT1M and MT1G genes expression on testicular sertoli cells. Methods: Cultured sertoli TM4 cells were exposed to different concentrations of Zn at different time points. Cellular uptake of Zn was tested using flame atomic absorption spectrometry. The cellular viability and gene expression were assessed by MTT and real-time PCR methods, respectively. Results: The treated cells resulted in higher Zn concentration and cellular viability. The expression of MT1M and MT1G genes in the treated cells were greater than those of the untreated cells (P<0.05). In the high dosage treated group (100 and 500 μM), Zn concentration and expression of MT1M and MT1G genes increased three h after treatment MT1G gene expression increased more at sixth h. At 18th h of treatment, the expression of both genes especially MT1G, increased dramatically while Zn concentration decreased. Conclusion: Since the increase of MT1G mRNA was coincident with cellular Zn level, it seems that MT1G has a more prominent role than MT1M in the homeostasis of Zn. In addition, Zn at dosage of 50 μM (pharmacologic concentration) may protect cells by increasing the expression of MT genes at longer periods.