Iranian

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Background: Mesenchymal stem cells (MSC) are a very promising transplantable stem cell source for a variety of cell replacement therapies. As the main source of MSC is bone marrow (BM), most of studies have been done on BM-derived MSC (BM-MSC). Umbilical cord (UC)-derived MSC (UC-MSC) which are recently introduced, is one of the good alternative source for these cells. The objective of this study was to isolate and characterize UC-MSC from human UC veins and studying of their potential to differentiate into various cell types such as fat, bone, cartilage and neuronal cells.  Methods: In this way, a cell population was isolated from 20 UC veins using a solution of 0.1% collagenase type IV. After identification of isolated cells by immunocytochemical and flow cytometry methods, these cells were exposured with adipogenic, osteogenic, chondrogenic and neurogenic agents. Resulted differentiated cells were detected using specific staining for each lineage and room temperature (RT)-PCR.  Results: Immunophenotypically, this cell population was positive for CD73, CD166, CD105 markers and a-smooth muscle actin and negative for CD31, CD34, CD49d markers, von Willebrand factor and smooth muscle myosin. Exposure of these cells to adipogenic, osteogenic, chondrogenic and neurogenic agents resulted in morphological changes followed by lineage-specific staining for each differentiated cell type. RT-PCR analysis showed that these differentiated cells express fat, bone, cartilage and neuronal markers, respectively.  Conclusion: Altogether, these findings indicate that UC-MSC possess morphological, immunophenotypical and cell differentiation capacities similar to BM-MSC and so they can be used more extensively in cell based therapy protocols and in vitro differentiation study models. 

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Background: The cultured mesenchymal stem cells (MSC) have been used in many clinical trials however, there are still some concerns about the cultural conditions. One concern is related to the use of FBS as a widely used xenogeneic supplement in the culture system. Human platelet-rich plasma (hPRP) is a candidate replacement for FBS. In this study, the effect of hPRP on MSC proliferation and osteogenic differentiation has been evaluated. Methods: Human adipose-derived stem cells (hADSC) were expanded. Cells from the third passage were characterized by flow cytometric analysis and used for in vitro experiments. Resazurin and alizarin red stains were used for cell proliferation and osteogenic differentiation assays, respectively. Results: Treatment with hPRP resulted in a statistically significant increase in cell proliferation compare to the negative control group (P<0.001). Cell proliferation in the 15% hPRP group was also significantly higher than that in the 10% hPRP group (P<0.05). Additionally, it caused less osteogenic differentiation of the hADSC compared to the FBS (P<0.001), but in comparison to negative control, it caused acceptable mineralization (P<0.001). Conclusion: These findings indicate that hPRP not only improves the proliferation but also it can be a suitable substitution in osteogenic differentiation for clinical purposes. However, the clinical application value of hPRP still needs more investigation.

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Background: Retinoic acid as one of the most important regulators for cell differentiation was examined in this study for differentiation of human umbilical mesenchymal cells (hUCM). Methods: After isolation, hUCM were evaluated for mesenchymal stem cell properties by flow cytometry and alkaline phosphatase assay. Also, doubling time of the cells and their differentiation potential into adipogenic and osteogenic cells were tested. hUCM were then cultured with different concentrations of retinoic acid, and on days 1, 7, and 12, the percentage of differentiated cells was determined by immunostaining for nestin, anti-microtubule associated protein 2 (MAP2), glutamic acid decarboxylase (GAD), and gamma-aminobutyric acid (GABA) markers. Results: The isolated cells were negative for the hematopoietic markers and positive for the mesenchymal markers. They showed the population doubling time 60 ± 3 hours and differentiated into osteogenic and adipogenic cells. A descending trend in nestin and an ascending trend in MAP2, GAD, and GABA expression were observed from the first day until the last day between different concentrations of retinoic acid. Conclusion: hUCM cells may have the potential to differentiate into neural cells in the presence of different incubation period and concentration of retinoic acid.

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Background: Hair follicle stem cells (HFSCs) located in the bulge area has shown to be highly proliferative and could differentiate into neurons, glia, smooth muscle cell, and melanocytes in vitro. Simvastatin is an HMG-CoA reductase inhibitor that exerts pleiotropic effects beyond simple low-density lipoprotein lowering and has a similar impact on the differentiation of bone marrow stromal cells and peripheral blood mononuclear cells. The present study examined the hypothesis that the application of simvastatin would induce the HFSCs differentiation into keratinocyte. Methods: The bulge of the hair follicle was anatomized, and HFSCs were cultivated. The flow cytometry and immunocytochemical staining for detection of nestin, CD34, and Kr15 biomarkers were performed before differentiation. In order to hasten the HFSCs differentiation to keratinocyte, HFSCs were treated with 1 µM, 2 µM, and 5 µM of simvastatin daily for a week. After differentiation, the flow cytometry and immunocytochemical staining were performed with Kr15 and Kr10 biomarkers, and the MTT assay was carried out as an index of cell viability and cell growth. Results: Our results showed that bulge of HFSCs were nestin and CD34 positive and Kr15 negative. Simvastatin significantly increased the viability of HFSCs (p < 0.05) at the concentration of 5 µM. In addition, the percentages of keratinocyte-differentiated cells treated with 5 µM of simvastatin showed a significant increase compared to all other treated groups (p < 0.05). Conclusion: Our findings demonstrate that 5 µM of simvastatin could induce HFSCs differentiation into keratinocyte.