Differentiation of mesenchymal stem cells from rat bone marrow into cardiomyocyte-like cells in vitro

Objective To explore the optimal condition for the differentiation of rat bone marrow mesenchymal stem cells (MSCs) into cardiomyocyte-like cells in vitro. Methods The MSCs were purified by percoll mediated density gradient centrifugation, and then randomly divided into A, B and C groups treated with 5, 10, 20 μmol/L 5-azacytidine, respectively. MSCs in each group were treated with 5-azacytidine for 12, 24 and 48 h, and then cultured for 28 d before examination. The morphological changes in MSCs were observed with inverted microscope. The expression of α-actin and cTnT was determined by immunohistochemistry and the protein expression of cTnT was determined by Western blotting. Results At day 28 after induction with 5-azacytidine, scattered myogenic structure was observed in the plasma of MSC under electronic microscope. Positive expression of α-actin and cTnT were detected with immunohistochemistry. As compared with 10 μmol/L (48 h) and 20 μmol/L (12, 24 and 48 h) subgroups, there was no significant difference in the expression of cardiac troponin T among 5 μmol/L (48 h) and 10 μmol/L (24 h) groups without effect on the biological characteristics. Conclusion MSCs could be differentiated into cardiomyocyte-like cells by 5-azacytidine in vitro. Induction with 5 μmol/L 5-azacytidine for 48 h or 10 μmol/L of 5-azacytidine for 24 h is the optimal condition for the differentiation of MSCs into cardiomyocyte-like cells in vitro.