肝细胞生长因子基因转染骨髓间充质干细胞对急性心梗大鼠心肌胶原合成的影响

Effect of hepatocyte growth factor-modified bone marrow mesenchymal stem cells transplantation on myocardial collagen synthesis in rats with acute myocardial infarction

目的探讨肝细胞生长因子(HGF)基因转染骨髓间充质干细胞(MSCs)对急性心梗大鼠心肌胶原合成的影响。方法通过结扎大鼠冠状动脉前降支制作SD大鼠急性心梗模型。40只SD大鼠随机分为对照组、假手术组、心梗组、MSCs组和MSCs-HGF组。所有MSCs移植前进行无血清、无氧条件培养6h;移植后4周HE染色与苦味酸天狼猩红染色观察大鼠心肌组织胶原分布、容积分数,ELISA法测心肌组织胶原Ⅰ、Ⅲ含量。结果 HE染色结果显示心梗组心肌细胞减少,结构紊乱,可见大量增生组织;MSCs-HGF组细胞形态结构较为完整,心肌组织间隙仅见少量增生组织。苦味酸天狼猩红染色显示:心梗组有大量红染纤维,呈束状或片状;MSCs-HGF组仅可见细束状红染纤维。ELISA结果可见:与心梗组相比较,MSCs-HGF组心肌组织胶原Ⅰ、Ⅲ含量均明显减少(P<0.05)。结论 HGF基因转染MSCs可抑制急性心梗大鼠心肌胶原的合成。

Objective To investigate the effect of hepatocyte growth factor（HGF）-modified bone marrow mesenchymal stem cells（MSCs）transplantation on myocardial collagen synthesis in rats with acute myocardial infarction（AMI）.MethodsAMI model was established by ligation of the anterior descending coronary artery in Sprague Dawley（SD）rats.Forty SD rats were randomly divided into controlgroup（Ctrl）,sham operation group（sham）,myocardial infarction group（MI）,MSCs transplantation group（MSCs）and HGF-modified MSCs transplantation group（MSCs-HGF）.Before transplantation,rats in MSC and HGF-MSC groups were cultured under serum-free and oxygen-free conditions for six hours.Four weeks after transplantation,collage distribution and collagen volume fraction of myocardium in rats were determined by hematoxylin and eosin（HE）and piciric acid-sirius red staining.Type I and type Ⅲ collagen contents in myocardium were detected by enzyme-linked immunosorbent assay（ELISA）.Results HE staining revealed that the number of cardiomyocytes in MI group decreased.Disturbed structure and increased tissue proliferation were also observed in MI group.The morphological structure of cardiomyocytes was more intact and less amount of proliferative tissue was observed in the interstitial space of cardiac tissue in MSCs-HGF group.Piciric acid-sirius red staining showed that lots of red fibers which were wispy and lamellated existed in MI group.Only red wispy fibers could be seen in MSCs-HGF group.The results of ELISA demonstrated that type Ⅰ and type Ⅲ collagen contents of cardiac tissue were significantly lower in MSCs-HGF group than those in MI group（P〈0.05）.Conclusion HGF-modified MSCs transplantation can inhibit myocardial collagen synthesis in AMI rats.