缺血再灌注损伤中miR-126的作用及对心肌细胞凋亡的影响  

Role of miR-126 in myocardial ischemia reperfusion injury and its influence on myocardial cell apoptosis

作　　者：郎明健[1] 王越[1] 李志[1] 陈娇[1] 何培根[1] 

机构地区：[1]湖北医药学院附属东风医院心血管内科,十堰442008

出　　处：《重庆医科大学学报》2017年第9期1131-1136,共6页Journal of Chongqing Medical University

基　　金：湖北省自然科学基金重点资助项目(编号:2060402-791)

摘　　要：目的:通过体内外实验探讨微小RNA(miR)-126在心肌缺血再灌注损伤中的作用及机制。方法:体外部分:心肌细胞H9C2分6组,建立心肌细胞模拟缺血/再灌注(simulated ischemia/reperfusion,SI/R)损伤模型,并分别转染miR-126mimic和miR-126inhibitor。qRT-PCR检测心肌细胞miR-126表达,流式细胞术检测细胞凋亡,Western blot检测caspase-3及其裂解片段的蛋白表达。体内部分:雌性Wistar健康大鼠分5组,建立缺血/再灌注损伤(ischemia/reperfusion,I/R)模型,并分别转染含有GFP的空病毒、miR-126mimic以及miR-126inhibitor的慢病毒。测定各组大鼠心肌梗死范围,TUNEL测定心肌细胞凋亡。结果:与对照组相比,心肌细胞H9C2SI/R后miR-126表达(0.32±0.02)明显降低(P=0.000)、细胞凋亡率(3.8±0.6)明显上升(P=0.000);与SI/R相比,采用miR-126mimic上调miR-126表达后细胞凋亡率(5.3±0.8)明显增加(P=0.007),caspase-3表达(0.450±0.003)明显降低(P=0.000),而采用miR-126inhibitor下调miR-126表达后细胞凋亡率(2.9±0.5)明显降低(P=0.000),caspase-3表达(1.80±0.03)明显升高(P=0.002)。与假手术组相比,I/R组和I/R+GFP组心肌梗死范围[(59.4±2.5),(60.2±2.8)]明显增加(P=0.000,P=0.000),而与I/R组相比,I/R+miR-126mimic组心肌梗死范围(69.0±2.4)明显增加(P=0.013),而I/R+miR-126inhibitor组心肌梗死范围(39.5±2.5)明显降低(P=0.000);TUNEL检测结果显示,与假手术组相比,I/R组和I/R+GFP组心肌细胞凋亡率[(33.4±1.7),(33.7±1.8)]明显升高(P=0.000,P=0.000);而与I/R组相比,I/R+miR-126mimic组心肌细胞凋亡率(42.2±2.3)明显增加(P=0.003),而I/R+miR-126inhibitor组心肌细胞凋亡率(25.5±1.5)明显降低(P=0.000)。结论:心肌缺血再灌注损伤会引起miR-126表达降低,而上调miR-126表达会促进心肌细胞凋亡,相反抑制miR-126表达可能有助于预防心肌缺血再灌注引起的心肌细胞凋亡。Objective：To explore the mechanism of miR-126 in myocardial ischemia reperfusion injury. Methods：In vitro,myocardial cells H9C2 were divided into 6 groups,and the myocardial cell simulated ischemia/reperfusion（SI/R）injury model was established,transfecting with the miR-126 mimic and miR-126 inhibitor. The expression of miR-126 was detected with real time-PCR in myocardial cells;apoptosis was detected with flow cytometry;and the expression of caspase-3 and its fragmentation were detected with Western blot. In vivo,healthy female Wistar rats were divided into 5 groups,and ischemia/reperfusion injury model was established.They were respectively disposed with the transfection of empty GFP,miR-126 mimic and miR-126 inhibitor virus. Myocardial infarction range was detected and the myocardial cell apoptosis was detected with TUNEL. Results：Compared with those of control group,the expression of miR-126 in myocardial cell H9C2 after SI/R was significantly reduced and the rate of apoptosis increased significantly. Up-regulation of miR-126 expression by miR-126 mimic could raise apoptosis rate and reduce caspase-3 expression significantly. On the contrary,down-regulation miR-126 expression by miR-126 inhibitor could reduce apoptosis rate and raise caspase-3 expression significantly. Compared with that of control group,myocardial infarction range increased significantly in the I/R group and the I/R ＋GFP group. Compared with that of I/R group,myocardial infarction range in the I/R＋miR-126 mimic group reduced significantly. TUNEL test results showed that compared with that of control group,the myocardial cell apoptosis rate in I/R group and the I/R＋GFP group increased significantly. Compared with that of I/R group,the myocardial cell apoptosis rate in I/R＋miR-126 mimic group increased significantly,while myocardial cell apoptosis rate in the I/R ＋ miR-126 inhibitor group decreased significantly,with statistically significant differences（P〈0.05）.Conclusion：miR-126 is down-regulated in myocardial isch

关 键 词：MIR-126 心肌缺血再灌注损伤 实验研究 

分 类 号：R542.2[医药卫生—心血管疾病]