miR-148b参与心肌梗死后心脏纤维化的作用及机制  

Role and mechanism of miR-148b involved in cardiac fibrosis after myocardial infarction

作　　者：赵娜[1] 李娜[2] 刘小军[1] 徐姣姣[1] 夏东雨 牛小麟[3] 刘仲伟[1] ZHAO Na LI Na LIU Xiao-jun XU Jiao-jiao XIA Dong-yu NIU Xiao-lin LIU Zhong-wei(Department of Cardiology, Shaanxi Provincial People’s Hospital, Xi’an 710068, Shaanxi, China Department of Cardiology, First Affiliated Hospital, Medical College, Xi’an Jiaotong University, Xi’an 710061, Shaanxi, China Department of Cardiology, Second Affiliated Hospital, School of Medicine, Xi’an Jiaotong University, Xi’an 710004, Shaanxi, China)

机构地区：[1]陕西省人民医院心内一科,陕西西安710068 [2]西安交通大学第一附属医院心内科,陕西西安710061 [3]西安交通大学第二附属医院心内科,陕西西安710004

出　　处：《心脏杂志》2017年第2期149-153,共5页Chinese Heart Journal

基　　金：国家自然科学青年基金项目资助(81400181)

摘　　要：目的探讨miR-148b参与大鼠心肌梗死后心脏纤维化的作用及可能机制。方法采用结扎大鼠冠状动脉左前降支方法制作大鼠心肌梗死模型,RT-PCR法评价大鼠心脏miR-148b表达水平;应用生物信息学方法预测miR-148b靶基因;采用Western blot方法评价大鼠心脏同源性磷酸酶-张力蛋白(phosphatase and tensin homologue,PTEN)及α-平滑肌蛋白(α-smooth muscle actin,α-SMA)蛋白表达水平;四甲基偶氮唑盐比色(MTT)法检测心脏成纤维细胞增殖能力;应用天狼猩红染色评价心脏纤维化病理改变。结果大鼠心肌梗死组,梗死周边区纤维化程度显著增加,miR-148b表达显著上调(P<0.01);miR-148b与预测靶基因PTEN mRNA有结合位点;大鼠心肌梗死组,梗死周边区PTEN表达显著下调(P<0.01);在心脏成纤维细胞中过表达miR-148b,PTEN的蛋白表达水平显著下调(P<0.01),α-SMA蛋白表达水平显著上调(P<0.01),细胞增殖能力显著增强(P<0.05);在Ang II诱导心肌纤维化细胞模型中,抑制miR-148b,PTEN蛋白表达水平显著上调(P<0.05),α-SMA蛋白表达水平显著下调(P<0.01),心脏成纤维细胞增殖显著减少(P<0.01)。结论 miR-148b通过PTEN参与心肌梗死后心脏纤维化作用。AIM To explore the role and mechanisms of miR-148b involved in cardiac fibrosis after myocardial infarction. METHODS The myocardial infarction model was induced by ligation of the left anterior descending coronary artery of rats. The target of miR-148b was predicted using bioinformatic methods. The expression level of miR-148b in rat heart tissue was evaluated using real-time PCR. The expression level of PTEN and α-SMA protein in rat heart tissue was evaluated using Western blot. Cardiac fibroblast proliferative ability was assessed using MTT assay and cardiac fibrosis was analyzed using Sirius red staining. RESULTS After myocardial infarction, fibrosis tissue increased and expression of miR-148b was up-regulated significantly in the border zone （P〈0.01）. The binding sites between miR-148b and PTEN mRNA were found. After myocardial infarction, the expression of PTEN was significantly down-regulated in the border zone （P〈0.01）. In the cardiac fibroblasts, miR-148b was overexpressed, PTEN protein expression level was significantly down-regulated （P〈0.01）, α-SMA protein expression level was significantly up-regulated （P〈0.01） and the proliferation of cardiac fibroblasts significantly increased （P〈0.05）. In the cardiac fibroblasts stimulated by AngII, miR-148b was inhibited, PTEN protein expression level was significantly up-regulated （P〈0.05）, α-SMA protein expression level was significantly down-regulated （P〈0.01） and the proliferation of cardiac fibroblasts was significantly decreased （P〈0.01）. CONCLUSION miR-148b is involved in cardiac fibrosis via PTEN after myocardial infarction.

关 键 词：心肌梗死 心脏纤维化 miR-148b PTEN 

分 类 号：R734.2[医药卫生—肿瘤]