骨髓间充质干细胞移植对大鼠心肌梗死后心室重构的影响

Effects of mesenchymal stem cells transplantation on post-infarction ventricular remodeling in rats

目的探讨骨髓间充质干细胞(mesenchymalstemcells,MSCs)移植对大鼠心肌梗死后心室重构和心功能的影响。方法取大鼠的骨髓,体外分离、扩增培养MSCs,BrdU标记。在结扎冠脉后1～2h将细胞直接注射到大鼠心脏梗死边缘区。6周后,采用超声心动图和解剖直测法获得大鼠心功能、心室重构和病理资料。结果与对照组比较,细胞移植组左室舒张末期和收缩末期内径缩短,左室前壁增厚,重量指数减小,长径增加,短轴周长缩短(P<0.05)。组织病理发现细胞移植组心梗区心肌数目增加,胶原形成明显减少,血管周围胶原沉积减少,血管密度上调,并在心梗区见到BrdU阳性细胞。结论骨髓间充质干细胞可以在心梗区定植,促进心肌和血管生成,减少胶原形成,从而延缓心肌梗死后心室重构,改善心功能。

Objective To investigate the feasibility and efficiency of mesenchymal stem cells transplantation on ventricular remodeling and heart function after myocardial infarction in rats. Methods MSCs were acquired from the bone marrow of adult rats. They were isolated, purified and cultured in ex vivo before transplantation. At 1 to 2 hours after left coronary artery ligation, the cultured cells, marked with BrdU, were directly injected into the border of cardiac infarction in rats. At 6 weeks after transplantation, the rat＇s heart function, ventricular remodeling and pathological Changes were measured by echocardiography, dissection, and immunohistochemistry, respectively. Results After transplantaed with MSCs LV end-diastolic diameter, horizontal circumference of mior axis and LV end-systolic diameter were shorter, LV walls was thickened, weight index was decreased, （ P 〈 0.05 ）, as compared with the control. MSCs transplantation prevented cardiac dilatation and reduced collagen content. The numbers of blood vessels and cardiomyocytes were increased at the margin of infarction site in the animals transplanted with MSCs. BrdU-labelled MSCs with oval nucleus were widely distributed. Conclusion MSCs could survive in host infarcted hearts. MSCs transplantation had benificial effects on remodeling processes and improved cardiac function, which was possibily related with the reduction of the amount of the collagen, and with myogenesis and angiogenesis.