骨骼肌干细胞移植抑制缺血心肌纤维化的实验研究

Implantation of skeletal muscle stem cells in inhibition of fibroatrophy of ischemic myocardium:an experimental study

目的 观察自体骨骼肌干细胞移植于缺血心肌后对心肌纤维化的抑制作用。方法 取12只成年犬臀大肌 ,分离卫星细胞、培养、传代 ,用 4′,6 二乙酰基 2 苯基吲哚 (DAPI)标记卫星细胞 ;在已建立的犬急性心肌梗死动物模型基础上 ;将DAPI标记的卫星细胞 ,自左冠状动脉前降支灌入缺血心肌中。分别于 2、4、8周后取出心脏 ,对缺血心肌的纤维化程度及植入的卫星细胞进行观察 ,并设对照组。结果 卫星细胞在缺血心肌中可分化成心肌细胞样细胞 ;在卫星细胞移植区域 ,心肌细胞的纤维化被有效抑制 ;对照组缺血心肌发生玻璃样变性 ,心肌细胞基本结构紊乱。结论 自体骨骼肌卫星细胞在缺血心肌中可分化成心肌细胞样细胞 ,并可抑制缺血心肌的纤维化 ;骨骼肌干细胞移植有望为心肌损伤提供一条新的治疗途径。

Objective To investigate the effect of stem cells derived from autogenous skeletal muscle, namely satellite cells, and implanted into ischemic myocardium on inhibition of myocardium fibroatrophy. Methods The left anterodecendant arteries (LAD) of 12 adult dogs were ligated so as to establish animal model of acute myocardiac infarction. Satellite cells isolated from the greatest gluteal muscle of dogs were labeled with 4′ 6-dimidino-2-phenylindone (DAPI), and then infused into the ventricular myocardium of the isogenic dogs through LAD. Specimens of ischemic myocardium were taken 2, 4, and 8 weeks after myoblast implantation. Histologic sections are examined under common light microscope and fluorescent microscope. Twelve dogs were used as controls. Results In the ischemic myocardium where satellite cells had been implanted, fibroaastrophy was efeectively inhibited. The implanted satellite cells had differentiated into fully developed striated muscle cells. Vitreous degeneration and disorder of basic structure could be observed in the ischemic myocardium in the control group. Conclusion The satellite cells from autologous skeletal muscle differentiate into cardiac muscle cell-like cells in the ischemic area and inhibit fibroatrophy of the ischemic myocardium after implantation, thus bringing a hope of a new cure for myocardial damage.