Differentiation of bone marrow mesenchymal stem cells coª²cultured with cardiomyocytes damaged by adyiamycin in vitro

    ZHANG Wei, ZHANG Rongª²Qing, JIA Guoª²Liang, LI Xue

    Department of Cardiovasology, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To study the differentiation of rabbit mesenchymal stem cells (MSCs) coª²cultured with neonatal rat cardiomyocytes damaged by adyiamycin and to find some evidence for cell transplantation for cardiomyopathy diseases. METHODS: Rabbit MSCs were isolated and cultured. After induced by 5ª²azacytidine and labeled by DAPI, MSCs were cocultured with adriamycin pretreated neonatal rat cardiomycytes in two different systems: a coª²culture system in which MSCs were mixed with cardiomyocytes directly (Contact group) and a doubleª²chamber system in which MSCs and cardiomyocytes were separately cultured in upper and lower chamber through Millicell, respectively (Millicell group). MSCs induced only by 5ª²azacytidine were regarded as control. On the 14th, 21st and 28th days, MSCs were identified by means of transmission electron microscopy technique and immunochemistry technique, respectively, and the differentiation rates in different groups were detected by flow cytometry. RESULTS: On the 21st and 28th day, some of the MSCs in the Millicell group and Control group expressed ¦Áª²sarcomeric actin and desmin positively and the positive cells were also found among DAPIª²labeled cells in the Contact group. Typical striation structure, rich glycogen granules and ovumlike centerª²locating neuclei were found in the cytoplasm by transmission electron microscopy. Compared with the other two groups, more doubleª²positive MSCs were found in the Contact group, whose ultrastructure was more mature. CONCLUSION: MSCs can undergo myogenetic differentiation in pathological cardiomyocyteª²microenvironment in vitro and their direct contact with cardiomyocytes is more crucial for the transdifferentiation of MSCs into cardiomyocytes than cytokine. MSCs may be a new cell source of cell transplantation in cardiomyopathy disease therapy. ......