miR-200b-3p Induces the Formation of Insulin-Producing Cells from Umbilical Cord Mesenchymal Stem Cells by Targeting ZEB2.

Studies have reported that miRNAs regulate β-cell differentiation, pancreatic development, and insulin secretion. However, the biological function of miRNAs during the formation of insulin-producing cells (IPCs) from umbilical cord-derived mesenchymal stem cells (UCMSCs) is poorly understood. Herein, the role and mechanism of miR-200b-3p during UCMSC differentiation into IPCs were investigated. UCMSCs were induced for IPC differentiation. An animal model was established by transplanting UCMSC-derived IPCs into streptozotocin-induced diabetic mice. Cell surface markers of undifferentiated UCMSCs and the expression of proinsulin and Pdx-1 in UCMSC-derived IPCs were measured by flow cytometry analysis. The interaction between miR-200b-3p and zinc finger E-box binding homeobox 2 (ZEB2) 3' untranslated region (UTR) was confirmed by luciferase reporter assay. Insulin secretion in UCMSC-derived IPCs was measured by enzyme-linked immunosorbent assay (ELISA). Islet marker (insulin and Pdx-1) levels were evaluated using immunofluorescence staining. In this study, undifferentiated UCMSCs had MSC phenotype and the potential for osteogenesis and adipogenesis. UCMSC-derived IPCs displayed glucose responsive insulin secretion and expressed insulin, Pdx-1 and proinsulin. miR-200b-3p was overexpressed in UCMSC-derived IPCs. Mechanically, miR-200b-3p targeted ZEB2. ZEB2 knockdown reversed the inhibitory effect of miR-200b-3p downregulation on IPC differentiation from UCMSCs in vitro. Moreover, miR-200b-3p silencing inhibited the anti-hypoglycemic effects and insulinogenesis of UCMSC-derived IPCs grafts in the kidney capsule of diabetic mice. Overall, miR-200b-3p induces the formation of IPCs from UCMSCs by targeting ZEB2.