the effects of exendine-4 on insulin producing cell differentiation from rat bone marrow-derived mesenchymal stem cells

objective: the aim of this study was to evaluate the effect of exendin-4 (ex-4) on differentiation of insulin-producing cells (ipcs) from rat bone marrow-derived mesenchymal stem cells (rat-bm-mscs). materials and methods: in this experimental study, rat-bm-mscs were cultured and the cells characterized by flow cytometry analysis of cell surface markers. rat-bm-mscs were subsequently treated with induction media with or without ex-4. after induction, the presence of ipcs was demonstrated with dithizone (dtz) staining and gene expression profiles for pancreatic cell differentiation markers (pdx-1, glut-2, insulin) were assessed using reverse transcription polymerase chain reaction (rt-pcr). insulin excreted from differentiated cells was analyzed with radioimmunoassay (ria). the two-tailed student’s t-test was used for comparison of the obtained values. results: the percentage of dtz-positive cells significantly increased in ex-4 treated cells (p<0.05). expression of the islet-associated genes pdx-1, glut-2 and insulin genes in ex-4 treated cells was markedly higher than in the cells exposed to differentiation media without ex-4. ria analysis demonstrated significant release of insulin with the glucose challenge test in ex-4 treated cells compared to ex-4 untreated cells. conclusion: the results of this study have demonstrated that ex-4 can enhance differentiation of ipcs from rat-bm-mscs.