Transplanted bone marrow mesenchymal stem cells protects myocardium by regulating 14-3-3 protein in a rat model of diabetic cardiomyopathy.

OBJECTIVE This study examined the mechanism of bone marrow mesenchymal stem cells (BMSCs) up-regulating the expression of 14-3-3 protein, blocking the myocardial apoptosis in diabetic cardiomyopathy and thereby improving cardiac function. METHODS AND RESULTS (1) Rat model of diabetic cardiomyopathy was made by feeding rats with high fat/high sugar diet and intraperitoneal injection of small dose of streptozocin (STZ). The model was successfully established as confirmed by the detection of blood sugar, lipid profile, ultrasonographic and hemodynamic examinations. (2) Bone marrow (BM) liquid was taken from the rat femur and tibia bones. The BMSCs were obtained by culture and were confirmed by phase-contrast microscopy and flow cytometry. The BMSCs were transplanted into the rats and fluorescent microscopy showed that transplantation was successful. (3) TUNNEL, Western blotting revealed that in rats of DCM group, myocardial apoptosis was more severe and expression of capase-3 was significantly up-regulated while in rats receiving transplantation of BMSCs showed opposite changes, with the differences being statistically significant (P < 0.05). (4) Western blotting exhibited that, compared with DCM group, 14-3-3 and p-Ask1 protein was significantly increased while Ask1 was obviously decreased. CONCLUSION Our findings suggested that transplantation of bone marrow mesenchymal stem cells could inhibit the myocardial apoptosis in diabetic cardiomyopathy, possibly by up-regulating the expression of 14-3-3 protein and inhibiting the phosphorylation of Ask1.