In Vitro Differentiation of Human Bone Marrow-Derived Mesenchymal Stem Cells into Cardiomyocyte-like Cells

Objective: Human mesenchymal stem cells (MSCs) have been recognized as potential candidates for cell therapy. In the present study, the ability of human bone marrow mesen- chymal stem cells (hBMSCs) to differentiate into cells with characteristics of cardiomyo- cytes in vitro was investigated. Materials and Methods: hBMSCs cultured in enriched medium were treated with oxy- tocin and 5-azacytidin. The differentiation of hBMSCs into cells that expressed cardiac- specific genes such as ?3-actinin, alpha - myosin heavy chain (?-MHC), beta - myosin heavy chain (B-MHC), myosin light chain isoform 2a (MLC2a), myosin light chain isoform 2v (MLC2v), artial natriuretic factor (ANF), GATA4 and oxytocin receptor (OTR) was in- vestigated by reverse transcription-polymerase chain reaction (RT-PCR). Protein expres- sions of B-actinin and troponin I-C in the cells were analyzed through immunofluores- cence staining. Results: MSCs are spindle-shaped with irregular processes. Cells treated with oxytocin and 5-azacytidin connected with adjoining cells to form myotube-like structures. Expres- sions of a number of cardiac-specific genes were detected by RT-PCR. Immunofluores- cence staining analysis showed that the differentiated cells stained positively for B-actinin and troponin I-C protein. Conclusion: These results indicate that adult hBMSCs can differentiate into cardiomyo- cytes in vitro by treatment with oxytocin and 5-azacytidin, and can be considered as a source of cells for cellular cardiomyoplasty.