Effect of cardiomyocytes-like cells transplantation on cardiac function of rats with ventricular aneurysm after myocardial infarction

AIM To observe the effect of cardiomyocytes-like cells induced from mesenchymal stem cells (MSCs）transplantation on the cardiac function of rats with functional ventricular aneurysm after myocardial infarction. METHODS Isolated MSCs from rats bone marrow were cultured in cell culture medium with 5-azacytidine (5-Aza) and labeled with 4,6-diamidino-2-phenylindole (DAPI）. Functional ventricular aneurysm model of rat was established by ligating the left enterior descending coronary artery and selected by ultrasonic cardiography (UCG) after 4 weeks. The rats with functional ventricular aneurysm were divided into cardiomyocytes-like cells group and control group then cardiomyocytes-like cells (106-107) or sodium chloride were injected at several different points into the broad area of ventricular aneurysm. In addition, 10 SD rats served as sham operation group (thoracotomy twice without ligation of coronary artery. Four weeks after transplantation, the cardiac function of the rats was measured by UCG and multichannel physiological recorder and the transplanted cardiomyocytes-like cells were detected by fluorescent microscope. RESULTS UCG showed that left ventricular end diastolic dimension (LVEDD) and left ventricular end systolic (LVESD) dimension in the three groups were （8.749±0.091）, （5.109±0.171）; (9.219±0.059), (5.942±0.092） and (6.344±0.296) mm, (3.116±0.275) mm, with sham operation group best（P<0.01） and cardiomyocytes-like cells group better than control group（P<0.05）. Fractional shortening (△FS) and left ventricular ejection fraction (LVEF) in the three groups were (32.70±1.283), (45.78±1.796); (22.80±0.593), (31.92±0.830) and (54.90±2.742)%, (74.12±2.760)%, with sham operation group highest（P<0.01） and cardiomyocytes-like cells group higher than control group（P<0.05）. Multichannel physiological recorder showed that left ventricular developed pressure (LVDP) and (±dp/dtmax) in the three groups were（152.9±0.669), (4 109±33.86), (-3 579±49.09); (122.5±2.639), (3 823±73.50), (-2 828±60.96) and (183.6±2.348) mmHg, (6 695±80.17) mmHg/s, (-6 294±71.39) mmHg/s, with sham operation group best（P<0.01） and cardiomyocytes-like cells group better than control group（P<0.05）. Labeled cardiomyocytes-like cells were found on the broad area of ventricular aneurysm in cardiomyocytes-like cells group. CONCLUSION Cardiomyocytes-like cells transplantation can improve the heart function of rat with functional ventricular aneurysm after myocardial infarction, provide a new therapeutic way and lay fundation for clinical reaserch.