缺氧预处理携带肝细胞生长因子的骨髓干细胞对急性心梗大鼠心功能的影响

The effect of hypoxia preconditioning MSC cells with HGF gene on the change of the heart function in AMI rats

目的 探讨缺氧预处理携带肝细胞生长因子（HGF）基因的骨髓间充质干细胞（MSCs）对急性心梗大鼠心功能及心肌胶原合成的影响.方法 通过结扎冠状动脉左前降支制作SD大鼠急性心肌梗死模型.随机分为5组：对照组、假手术组、心梗组、MSCs组和MSCs-HGF组.移植后4周心彩超测定大鼠心功能;HE染色观察心肌组织结构;天狼星红染色测心肌组织胶原;PCR法测心肌HGFmRNA表达;免疫印迹检测心肌HGF蛋白表达;ELISA法测心肌组织胶原Ⅰ、Ⅲ含量.结果 与心梗组相比,MSCs-HGF组左室射血分数（LVEF）明显好转[（75.42±7.82）％比（66.36±8.55）％,P＜0.01].PCR与Western-bloting结果示,MSCs-HGF组心肌组织HGF mRNA及蛋白表达显著增加,其他各组均未见到表达;HE染色显示心梗组心肌细胞减少,可见大量增生组织;MSCs-HGF组心肌细胞较为完整,间隙仅见少量增生组织.天狼星红染色显示心梗组有大量红染纤维,MSCs-HGF组仅可见细束状红染纤维.ELISA结果显示,与心梗组相比,MSCs-HGF组心肌组织胶原Ⅰ含量[（450±12）pg/ml比（523± 13）pg/ml,P＜0.05]、组织胶原Ⅲ含量[（870±14）pg/ml比（1080±25）pg/ml,P＜0.05]均明显著降低.结论 缺氧预处理携带HGF基因的MSCs改善心梗大鼠心功能可能与其抑制心梗后心肌纤维化有关.

Objective To observe the effect of hypoxia preconditioning MSC cells with hepatocyte growth factor （HGF） gene on the change of the heart structure and function and collagen synthesis in AMI rats.Methods Acute myocardial infarction （AMI） model was established by ligating left anterior descending coronary artery.40 Rats were randomly divived into 5 groups （8 rats per group）：control group,sham-operated group,AMI group,MSCs group,MSCs-HGF group.Echocardiography was performed to measure left ventricular ejection fractions （EF）.Cardiac hemodynamics was evaluated with left cardiac catherization.Hematoxylin-eosin （HE） and Situs red staining were used to determine myocardial structure and collagen deposition.RT-PCR was performed to determine the expression of HGF mRNA.The level of HGF protein was estimated by Western-blotting.Enzyme Linked Immunosorbent Assay（ELISA） was used to assay the levels of collagen Ⅰ,Ⅲ.Results Compared with AMI groups：the left ventricular ejection fraction（EF） were significantly increased in MSCs-HGF group[（75.42±7.82）% vs AMI groups（66.36±8.55）%,P〈0.01];Real-time PCR and Western-bloting shown：the levels of HGF mRNA and protein were remarkable elevated in MSCs-HGF group compared with those in MSCs group （P〈0.01）.There were no the expression of HGF mRNA and protein in control,sham,AMI and MSCs group.HE staining shown that in AMI rats myocardial cells lowed,disordered,A large number of fibrous tissue deposition,in MSCs HGF group only A small amount of fibrous tissue deposition.Myocardial tissue Sirius red staining,in AMI group a large number of beam and plate red dye of myocardial tissue,in MSCs-HGF group wispy bouquet of red dye of myocardial tissue.ELISA analysis shown the level of collagen Ⅰ,Ⅲ in heart tissue were greatly increased in AMI group while those were significantly decreased in MSCs-HGF group[collagen Ⅰ （450±12）pg/ml vs AMI groups（523±13）pg/ml,P〈0.05;collagen Ⅲ （870± 14）pg/ml vs AMI groups（1080±25）pg/ml,P〈0.05].Conclusion Hypoxia pretreated MSC ceils with HGF gene improves cardiac function possibly through inhibiting myocardial fibrosis in AIM rats.