微小RNA-499对脓毒症心功能障碍大鼠肌球蛋白重链的影响  

Effect of microRNA-499 on myosin heavy chain in rats with sepsis and cardiac dysfunction

作　　者：杨永丽 刘海珍 钟准 YANG Yongli;LIU Haizhen;ZHONG Zhun(Dept.of Critical Care Medicine,Hubei No.3 People's Hospital of Jianghan University,Wuhan 430033,Hubei,China;Dept.of Cardiovascular Medicine,Hubei No.3 People's Hospital of Jianghan University,Wuhan 430033,Hubei,China;Dept.of Otorhinolaryngology,Hubei No.3 People's Hospital of Jianghan University,Wuhan 430033,Hubei,China)

机构地区：[1]江汉大学附属湖北省第三人民医院重症医学科,湖北武汉430033 [2]江汉大学附属湖北省第三人民医院心血管内科,湖北武汉430033 [3]江汉大学附属湖北省第三人民医院耳鼻喉科,湖北武汉430033

出　　处：《武汉大学学报（医学版）》2022年第4期618-623,共6页Medical Journal of Wuhan University

基　　金：湖北省卫生健康委科研基金资助项目(编号:WJ2021F130)。

摘　　要：目的:探讨微小RNA-499(miR-499)调节α型和β型肌球蛋白重链(α-MHC、β-MHC)在脓毒症心功能障碍(SMD)中的作用及机制。方法:成年雄性Sprague-Dawley大鼠,体质量约200~250 g,随机分组为假手术组(sham组)、SMD模型组[脂多糖(LPS)组)]和miR-499激动剂组(LPS+anomir组),使用腹腔注射LPS(10 mg/kg)诱发脓毒症心功能不全建立模型,干预组在大鼠造模前连续3 d通过尾静脉给予注射miR-499激动剂(anomir:30 mg/kg)进行干预。采用超声心动仪测量左心室射血分数(EF)和短轴缩短率(FS),采用定量聚合酶链反应(QPCR)检测miR-499、α-MHC、β-MHC基因水平,采用蛋白质免疫印迹试验检测α-MHC、β-MHC的蛋白表达量,采用电化学发光仪及其专用试剂盒测定血浆NT-proBNP浓度。结果:LPS刺激后大鼠血浆和心肌组织中miR-499的表达下调(P<0.01)、α-MHC mRNA及其蛋白的表达水平下降(P<0.001),β-MHC mRNA及其蛋白的表达水平显著升高(P<0.01),左心室射血分数下降(P<0.01),血浆NT-proBNP浓度升高(P<0.001)。通过静脉注射miR-499的模拟物(agomir)过表达miR-499的水平后发现,大鼠β-MHC/α-MHC的失调被逆转,左心室射血分数增高(P<0.01),血浆NT-proBNP浓度下降(P<0.001)。结论:miR-499能通过调节α-MHC、β-MHC的表达水平,改善脓毒症引起的大鼠心功能障碍,靶向miR-499可以成为治疗脓毒症引起的心脏功能障碍的有效途径。Objective:To investigate the mechanism of miR-499 regulatingα-MHC andβ-MHC in septic myocardial dysfunction.Methods:Adult male Sprague Dawley rats weighing 200-250 g were randomly divided into sham operation group(sham group),SMD model group(LPS group),and miR-499 agonist group(LPS+anomir group).The model of septic cardiac insufficiency was induced by intraperitoneal injection of lipopolysaccharide(LPS:10 mg/kg).The intervention group was intervened by injecting miR-499 agonist(anomir:30 mg/kg)through caudal vein for 3 days before modeling.Left ventricular ejection fraction(EF)and fractional shortening(FS)were measured by echocardiography;miR-499,α-MHC,andβ-MHC mRNA levels were detected by Q-PCR;α-MHC andβ-MHC protein expression was detected by Western Blot;The concentration of NT-proBNP in plasma was determined by electrochemiluminescence.Results:After LPS stimulation,the expression of miR-499 in plasma and myocardial tissue decreased(P<0.01),the expression levels ofα-MHC mRNA and protein decreased(P<0.001),the expression levels ofβ-MHC mRNA and protein increased significantly(P<0.01),the left ventricular ejection fraction decreased(P<0.01),and the plasma NT-proBNP concentration increased(P<0.001).Theβ-MHC/α-MHC dysregulation was reversed after the overexpression of miR-499 by the intravenous administration of miR-499 agomir,the left ventricular ejection fraction increased(P<0.01),and the plasma NT-proBNP concentration decreased(P<0.001).Conclusion:miR-499 can improve sepsis induced cardiac dysfunction in rats by regulating the expression levels ofα-MHC andβ-MHC,and targeting miR-499 can be an effective approach for the treatment of sepsis induced cardiac dysfunction.

关 键 词：miR-499 脓毒症 心功能障碍 α-MHC Β-MHC 

分 类 号：R541.9[医药卫生—心血管疾病]