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Directing the fate of mesenchymal stem cells (MSCs) to dopaminergic neurons has great importance in both biomedical studies and cell therapy of Parkinson's disease. We recently generated dopamine-secreting cells from human adipose tissue-derived stem cells (hADSCs) by exposing the cells to a growth factor cocktail composed of SHH, bFGF, FGF8 and BDNF in low-serum condition. In the current study, we induced the cells by the same dopaminergic inducing cocktail in serum-free B27-supplemented Neurobasal medium. ADSCs differentiated in both conditions expressed several neuronal and dopaminergic markers. However, there were higher gene expression levels under the serum-free condition. Higher levels of TUJ1 and TH proteins were also detected in the cells exposed to the dopaminergic-inducing cocktail under serum-free Neurobasal condition. TH protein was expressed in about 28% and 60% of the cells differentiated in the low-serum and serum-free Neurobasal media, respectively. Moreover, the cells exposed to the dopaminergic-inducing cocktail in the serum-free Neurobasal condition released a more significant amount of dopamine in response to KCl-induced depolarization. Altogether, these findings show a greater efficiency of the serum-free Neurobasal condition for growth factor-directed differentiation of hADSCs to functional dopamine-secreting cells which may be valuable for transplantation therapy of Parkinson's disease in future.

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Adipose tissue-derived stem cells (ADSCs) are capable of multipotential differentiation and express several angiogenic, anti-apoptotic and immunomodulatory markers. These features make adipose tissue as a promising source of stem cells for regenerative medicine. However, for efficient translational use, culture-induced changes in the gene expression profile and resistance of the ADSCs to ischemic environment should be taken into consideration. We compared the expression of some clinically important markers between the unpassaged and third-passaged ADSCs by RT-PCR, qPCR and flow cytometry. Our results demonstrated that the embryonic stem cell (ESC)-specific markers were expressed in the unpassaged ADSCs but were downregulated after three passages. The expression of stemness-related genes, TGFB and FGF2, was upregulated while FGF4 and LIF were downregulated after three passages. The expression of angiogenic genes in the third-passaged ADSCs was higher than the unpassaged cells. Epithelial-mesenchymal transition (EMT) markers were either expressed in the third-passaged ADSCs or significantly upregulated after three passages. In contrast, cell cycle inhibitors, CDKN1A and TP53, were downregulated with early subcultures. The unpassaged and third-passaged ADSCs showed nearly similar resistance to oxidative stress, hypoxia and serum deprivation. In conclusion, the primary cultures of human adipose tissue contain a subpopulation of cells expressing ESC-specific genes and proteins, but the expression of these pluripotency markers subsides rapidly in standard mesenchymal stem cell culture medium. The expression of angiogenic and EMT markers also varies with early subcultures. Altogether, early-passaged ADSCs may be better choices for transplantation therapy of injured tissues, especially after ischemic conditions.

RESUMEN

Type 2 diabetes mellitus (T2DM) is a multifactorial metabolic disorder which is characterized by chronic hyperglycemia. T2DM is due to the interplay of genetic susceptibility and environmental factors. Zinc is an important element for insulin storage and secretion. Zinc transporters ensure zinc transportation across the biological membranes and enable the cellular flow of zinc into the extracellular matrix or the intracellular vesicles. Solute carrier family 30 member 8 (SLC30A8) gene encodes zinc transporter protein member 8. The rs13266634 C/T polymorphism in SLC30A8 gene has been reported with higher risk of T2DM in literature. Thus, the present study aimed to investigate the association between rs13266634 polymorphism and T2DM in Fars province, Southern Iran and compare the results with other populations. A total of 306 subjects were collected from the outpatients of Shahid Motahhari clinic affiliated to Shiraz University of Medical Sciences, Shiraz, Iran. These subjects were genotyped using polymerase chain reaction-restriction fragment length polymorphism and validated by direct sequencing. The frequency of CC genotype in diabetic and control groups was 90 (59.6%) and 89 (57.4%). The number of CT genotype was 51 (33.8%) in the case and 49 (31.6%) in the control group. The TT genotype was 10 (6.6%) and 17 (11%) in diabetic and non-diabetic subjects, respectively. No significant difference was found between the normal and T2DM subjects regarding the allelic and genotypic distribution (p=0.35, OR=1.19, 95% CI 0.82-1.7) and (p=0.94, OR=1.7, 95% CI 0.7-3.9). No significant difference was found between the normal and diabetic subjects regarding the rs13266634 C/T polymorphism in SLC30A8 gene. In comparison with other ethnic groups, the C allele frequency in our population was very similar to that of the European but higher than that of the Eastern Asian and lower than the African populations.

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