Abstract: Objective The aim of this study is to improve the potential of pancreatic progenitor cells differentiation of human placenta derived mesenchymal stem cells (PMSCs) by miR-124a mediates post-transcriptional regulation of its mRNA targets TGFBR1 and BMPR1B . Methods We used lentiviral vectors to stably and specifically over express miR-124a and inhibited the miR-124a function by its antagomir. In addition, we analyzed the relationship between miR-124a and target genes expression. Real-time PCR, Western blot and immunofluorescent staining were used to test the mRNA and protein expression variation and assess the ability of PMSCs to differentiate into pancreatic progenitor cells. Results Overexpression of miR-124a led to repression of endogenous TGFBR1 and BMPR1B, and inhibition of miR-124a relieved the repression of TGFBR1 and BMPR1B. Overexpression of miR-124a in PMSCs resulted in up-regulated of pancreatic-specific genes (Ngn3, Nkx6.1, PDX-1 and Insulin) (P<0.05)and increased proportions of Insulin and PDX-1 positive events compared to control treated cells. Conclusion miR-124a is involved in pancreatic progenitor cells differentiation of PMSCs partially via suppression of the TGFBR1 and BMPR1B genes. Furthermore, the miR-124a accelerates pancreatic progenitor cells differentiation, possibly mediated by TGF β pathway.

Key words: miR-124a,TGF β R1,pancreatic precursor cell,placenta mesenchymal stem cells,differentiation