ABSTRACT
Mesenchymal stem cells (MSCs) have been reported to be an attractive source for the generation of transplantable surrogate ß cells. A murine embryonic mesenchymal progenitor cell line C3H10T1/2 has been recognized as a model for MSCs, because of its multi-lineage differentiation potential. The purpose of this study was to explore whether C3H/10T1/2 cells have the potential to differentiate into insulin-producing cells (IPCs). Here, we investigated and compared the in vitro differentiation of rat MSCs and C3H10T1/2 cells into IPCs. After the cells underwent IPC differentiation, the expression of differentiation markers were detected by immunocytochemistry, reverse transcription-polymerase chain reaction (RT-PCR), quantitative real-time RT-PCR (qRT-PCR) and Western blotting. The insulin secretion was evaluated by enzyme-linked immunosorbent assay (ELISA). Furthermore, these differentiated cells were transplanted into streptozotocin-induced diabetic mice and their biological functions were tested in vivo. This study reports a 2-stage method to generate IPCs from C3H10T1/2 cells. Under specific induction conditions for 7-8 days, C3H10T1/2 cells formed three-dimensional spheroid bodies (SBs) and secreted insulin, while generation of IPCs derived from rat MSCs required a long time (more than 2 weeks). Furthermore, these IPCs derived from C3H10T1/2 cells were injected into diabetic mice and improves basal glucose, body weight and exhibited normal glucose tolerance test. The present study provided a simple and faithful in vitro model for further investigating the mechanism underlying IPC differentiation of MSCs and cell replacement therapy for diabetes.
Subject(s)
Diabetes Mellitus, Experimental/therapy , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/transplantation , Insulin/biosynthesis , Mesenchymal Stem Cells/cytology , Animals , Biomarkers , Blood Glucose/metabolism , Body Weight , Cell Differentiation , Cell- and Tissue-Based Therapy/methods , Cells, Cultured , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Gene Expression , Glucose Tolerance Test , Insulin/metabolism , Insulin Secretion , Insulin-Secreting Cells/metabolism , Male , Mesenchymal Stem Cells/metabolism , Mice , Rats , Rats, Sprague-Dawley , Spheroids, Cellular , StreptozocinABSTRACT
Mesenchymal stem cells (MSCs) are pluripotent progenitors that can differentiate into a variety of cell types. Vascular endothelial growth factor (VEGF) is one of the major factors of initiating and regulating angiogenesis. It has been reported that VEGF can induce MSCs differentiated into endothelial cells (ECs). However, the mechanism that VEGF-induced MSC differentiation is not completely understood. Here, we showed that VEGF induced human and rat bone marrow-derived MSCs differentiation to ECs. Rho family plays an important role in VEGF-induced endothelial cell migration and angiogenesis. Our results indicated that in MSCs, VEGF activated Rho/ROCK signaling pathway and promoted nuclear translocation of myocardin-related transcription factor-A (MRTF-A), which is controlled by Rho/ROCK signaling. In addition, Rho inhibitor C3 transferase, ROCK inhibitor Y27632 or depletion of endogenous MRTF-A abolished the VEGF-induced differentiation of MSCs into ECs. Furthermore, VEGF also enhanced the expression levels of CYR61/CCN1, as a regulator of vascular development and angiogenesis, and knockdown of endogenous MRTF-A reduced VEGF-induced the upregulation of CYR61/CCN1. Report assays with site-direct mutation analysis of CYR61/CCN1 promoter demonstrated that MRTF-A transactivated CYR61/CCN1 promoter mainly depending on CArG box. In this study, we identify the Rho/MRTF-A signaling pathway as a main actor in controlling VEGF-induced differentiation of human and rat bone marrow-derived MSCs into endothelial cells.
