Mechanisms Of Cardiomyocytes Differentiation From Human Bone Marrow Mesenchymal Stem Cells In Vitro

Objective: To investigate the mechanisms ofcardiomyocytes(CMs) differentiation in vitro from human bonemarrow mesenchymal stem cells (hBMSCs) induced by5-Azacytidine(5-Aza) in oxidative stress conditions.Methods: hBMSCs were obtained and subsequently cultured invitro with whole bone marrow adherent method, and the fourthto sixth generation of hBMSCs were harvested. Cells weredivided into four groups, control group,5-Aza group, H2O2+5-Azagroup and positive control group. In5-Aza group, hBMSCs weretreated for15days with10μmol/L5-Aza, and in H2O2+5-Azagroup, cells were pretreated with200μM hydrogen peroxidesolution for12hours before5-Aza treatment.Immunocytochemical staining and Flow cytometry of TroponineIwas used to identify cardiomyocyte differentiation. RhoAexpression was detected by RT-PCR.Results: hBMSCs treated with10μmol/L5-Aza expressedcardiac-specific marker TroponineI, however, in H2O2+5-Azagroup, only a few cells were positive for TroponineI. RT-PCRanalysis showed that RhoA expression was higher in5-Aza group,but lower in H2O2+5-Aza group.Conclusion: hBMSCs have the potential to differentiate intoCardio-myocytes.5-Aza may facilitate the cardiomyocytedifferentiation by activating RhoA. The ability of hBMSCs cardiomyocytes differentiation could be inhibited by H2O2, andpossibly inhibited by RhoA pathway.