Inducing Human Bone Marrow-derived Mesenchymal Stem Cells To Differentiate Into Cardiomyogenic Cells In Vitro

Objective: To study the condition of human bone marrow-derived mesenchymal stem cells (hBMSCs) induced to differentiate into cardiomyocytes in vitro.Methods: hBMSCs were derived from adult bone deserted in operation. To estabilish c-kit~+ of hBMSCs that have potential to differentiate specially towards cardiomyocytes, the c-kit~+ hBMSCs cell clones were selected. These cells were incubated in low glucose DMEM medium with 20% FBS, then they were induced to differentiation. the c-kit~+ cells were exposured in 10μmol/l 5-azacytidine,100mg/l traditional chinese medicine and 10μmol/l 5-azacytidine adds 100mg/l traditional chinese medicine respectively for 24 hours, then incubated in low glucose DMEM medium contain 10% FBS. Cells were harvested at 21 days. To identified the differentitated cardiomyocytes, cardiac specific proteins :Desmin and cTnT were assayed with immunocytochemistry and cardiac specific gene :ANP and BNP were detected with RT-PCR.Results: There were multiple hBMSCs clones in human bone marrow and fibroblast-like cell clones were c-kit~+.After they were induced by 5-azacytidine and traditional chinese medicine ,parts of the cells grew to puncheon-like and parallel during the second week.The cell conjunction and myotube-like structures were found during the third week. The cross-striations were observed in parts of the inducing cells.Desmin positive cells were 65.3±4.7 % in 5-azacytidine, 62.3±3.9 % in traditional chinese medicine and 68.5±2.1% in 5-azacytidine adds traditional chinese medicine respectively. The cTnT positive cells were 62.2±4.1% in 5-azacytidine, 63.8±3.4% in traditional chinese medicine and 66.0±6.2% in 5-azacytidine adds traditional chinese medicine respectively. ANP and BNP were observed in the inducing cells.Conclusion: The c-kit~+ hBMSCs clones can be differentiated specially towards cardiomyocytes after induction with 5-azacytidine and traditional chinese medicine in vitro. The differentiated cells demonstrated the structural and functional characteristics of the immature cardiomyocytes. Not only selecting the c-kit~+ hBMSCs have specific differentiate towards cardiomyocytes but also increasing the positive percentage in this way.