微小RNA-21在小鼠慢性病毒性心肌炎心肌纤维化中的作用  

The effect of microRNA-21 on myocardial fibrosis in mice with chronic viral myocarditis

作　　者：薛贻敏 陈明光[1] 陈德伟[1] 伍伟锋[2] 刘艳丽[3] 林风辉[1] Xue Yimin;Chen Mingguang;Chen Dewei;Wu Weifeng;Liu Yanli;Lin Fenghui(Fourth Department of Critical Care Medicine, Fujian Provincial Hospital, Provincial Clinical College of Fujian Medical University, Fuzhou 350001, China)

机构地区：[1]福建医科大学省立临床医学院福建省立医院重症医学四科,福州350001 [2]广西医科大学第一附属医院心内科 [3]广西医科大学第一附属医院老年心内科

出　　处：《中华心血管病杂志》2018年第6期450-457,共8页Chinese Journal of Cardiology

基　　金：国家自然科学基金(81050020);福建省医学创新课题(2016-CX-1)

摘　　要：目的研究微小RNA-21（miR-21）对小鼠慢性病毒性心肌炎（CVMC）心肌纤维化的影响及其可能机制。方法雄性4周龄Balb/c小鼠40只按照随机数字表法分为磷酸盐缓冲液（PBS）组、CVMC组、CVMC＋miR-21抑制剂组和CVMC＋同型对照组，每组各10只。首次注射柯萨奇B3病毒（CVB3）液或PBS定为第0天，研究总时间为42 d。CVMC组、CVMC＋miR-21抑制剂组和CVMC＋同型对照组的小鼠均于第0、14和28天经腹腔注射100TCID50的CVB3液0.1、0.15和0.2 ml/只，同时点PBS组小鼠注射相同剂量的PBS。CVMC＋miR-21抑制剂组和CVMC＋同型对照组小鼠在第14和28天注射病毒液后分别经尾静脉注射miR-21抑制剂0.1 ml/只或同型对照0.1 ml/只。42 d后行超声心动图检查评估小鼠心功能，然后无菌留取小鼠心脏，观察心肌绿色荧光蛋白（GFP）的表达，同时行苏木素伊红及Masson染色观察心肌病理学特征，并计算心肌病理积分（PS）及胶原容积积分（CVF），实时荧光定量逆转录聚合酶链反应测定小鼠心肌中miR-21、Ⅰ型胶原（COL1-A1）及Ⅲ型胶原（COL3-A1）mRNA的表达，Western blot法测定心肌中转化生长因子-β1（TGF-β1）和母亲DPP同源物7（Smad7）蛋白的表达。结果（1）超声心动图检查结果：CVMC组和CVMC＋同型对照组小鼠左心室收缩末期内径（LVESD）、左心室舒张末期内径（LVEDD）均明显高于PBS组（P均〈0.05），左心室射血分数（LVEF）明显低于PBS组（P〈0.05）。CVMC＋miR-21抑制剂组小鼠LVESD、LVEDD均低于CVMC组和CVMC＋同型对照组（P均〈0.05），LVEF明显高于CVMC组和CVMC＋同型对照组（P均〈0.05）。（2）心肌病理学检测结果：CVMC＋miR-21抑制剂组和CVMC＋同型对照组小鼠心肌切片在荧光显微镜下可见GFP表达。CVMC组和CVMC＋同型对照组小鼠心脏肿大僵硬，镜下可见心肌散在坏死灶，周围少量炎性细胞浸润，间质成纤维细胞增生明显，胶�Objective To explore the effect of microRNA-21 （miR-21） on myocardial fibrosis in mice with chronic viral myocarditis （CVMC） and related mechanisms. Methods Forty 4-week-old Balb/c male mice were randomly divided into 4 groups （n=10 each）： phosphate buffer saline （PBS） group, CVMC group, CVMC ＋ miR-21 inhibitor group, CVMC ＋isotype control group. The first injection of Coxsackie virus B3 （CVB3） or PBS was performed on day O, and the total study time was 42 days. Each mouse in CVMC group, CVMC＋miR-21 inhibitor group and CVMC＋isotype control group was intraperitoneally （i.p） injected with 100TCID50 CVB3 0.1, 0.15, and 0.2 ml on day 0, 14, and 28, respectively. The mice in PBS group were i. p injected with the same dose of PBS at the same time point. After the initial infection, each mouse in CVMC＋miR-21 inhibitor group and CVMC＋isotype control group was intravenously injected with 0.1 ml miR-21 inhibitor or 0.1 ml isotype control, on day 14 and 28. Cardiac function was measured on surviving mice of 4 groups by echocardiography on day 42. Then, the hearts were removed aseptically to observe the expressions of green fluorescence protein （GFP）. The myocardial pathological changes were examined with HE, Masson staining and the myocardial pathological scores （PS）, the collagen volume fraction （CVF） were calculated respectively. The levels of miR-21, collagen type I -A1 （COL1-A1） and collagen type m-A1 （COL3-A1） mRNA in heart were detected by quantitative real-time polymerase chain reaction （RT-qPCR）. Furthermore, the expressions of transforming growth factor-J31 （TGF--I） and mothers against decapentaplegic homolog 7（Smad7） in heart were determined with Western blot assay. Results （1） Cardiac function in 4 groups： Compared with PBS group, left ventricular end systolic diameter （LVESD） and left ventricular end diastolic diameter （LVEDD） were markedly increased in CVMC group and CVMC＋isotype control group （all P〈0.05）, whereas the l

关 键 词：心肌炎 心肌纤维化 微小RNA-21 

分 类 号：R542.2[医药卫生—心血管疾病]