Repairing effect of sarcoblasts from mesenchymal stem cells induced by MyoD transfection on muscle injury / 解放军医学杂志

ABSTRACT

Objective To observe the repairing effects of myoblasts from mesenchymal stem cells induced by MyoD transfection on muscle injury, and to explore its mechanism. Methods One hundred and sixty male SCID mice were randomly assigned into 4 groups [normal group, control group with injury, implantation with mesenchymal stem cells (MSCs) group, and implantation with myoblasts group]. MSCs were transfected by pIRES2-EGFP-MyoD and differentiated into myoblasts. Myoblasts and MSCs were injected respectively into the muscular tissue injuried by cardiotoxin. The repairing effect in injuried muscles, which were injected with myoblasts and MSCs, was observed 1, 2, 4 and 6 weeks after the injection. Results The muscular tissue injury model was successfully reproduced. Both MSCs and myoblasts showed obvious repairing effects on the injured muscular tissue, and the strength of muscular tissue in myoblasts group was stronger than that in MSCs group. Western blot assay showed that MyoD expression in myoblasts group was much higher than that in both MSCs and control groups, the expressions of JNK1 and ERK2 were up-regulated in myoblasts group, and the p38 expression was down regulated significantly in the 1st week, but no significant difference was found when compared with those of the normal group at the 6th week. Conclusion Myoblasts transdifferentiated from MSCs induced by MyoD can repair the injuried muscular tissue effectively. JNK1, p38 and ERK2 play important roles in the repairing process.