Vitamin D supplementation affects bone marrow-derived mesenchymal stem cells differentiation into insulin-producing cells

Background this study was conducted to assess the effects of vitamin D on differentiation of bone marrow- derived mesenchymal stem cells (BM-MSCs) into insulin producing cells (IPCs). Method BM-MSCs were isolated from femur and tibia of rats and incubated in low (LG) or high glucose (HG) (5mM or 25mM), or high glucose DMEM media supplemented with vitamin D (0.2nM) (HGD) for 14 days. Cells viability was analysis by MTT assay. Differentiation of SCs was confirmed using measuring genes expression level of pdx(1) and insulin, and insulin secretion, glucose stimulated insulin secretion, and insulin content by ELISA method. Results Cell viability was significantly higher in HGD than LG (p < 0.05) in day 3, also, in HG and HGD than LG (p < 0.001), and HGD vs. HG (p < 0.001) in day 7. Pdx1 and insulin level was markedly higher in HGD than LG (p < 0.05 and p < 0.01). pdx1 expression was markedly higher in HGD (p < 0.05) than LG, also insulin expression the HG (p < 0.05), and HGD (p < 0.01) groups compared to the LG group. Insulin release at 5mM glucose was notably higher in the HGD group compared to LG (p < 0.05), and at 25mM glucose, both HG and HGD showed significant increases vs. LG (p < 0.05 and p < 0.01, respectively). Insulin content was significantly higher in both 5mM and 25mM glucose for HG and HGD vs. LG (p < 0.01 and p < 0.001, respectively). In conclusion, treatment BM-MSCs with vitamin D could increase their differentiation into IPCs and it can be considered as a potential supplementary agent in enhancing differentiation SCs into insulin generating cells.