右美托咪定对缺氧复氧诱导心肌细胞凋亡的防护作用及机制  

Protective effect and mechanism of dexmedetomidine of hypoxia/reoxygenation-mediated cardiomyocyte apoptosis

作　　者：车昊[1] 马骏[1] Che Hao;Ma Jun(Anesthesia Center,Beijing Anzhen Hospital,Capital Medical University,Beijing 100029,China)

机构地区：[1]首都医科大学附属北京安贞医院麻醉中心,100029

出　　处：《中国医药》2021年第5期758-762,共5页China Medicine

基　　金：国家自然科学基金(81871592)。

摘　　要：目的探讨右美托咪定(Dex)对缺氧复氧诱导心肌细胞凋亡的防护作用及机制。方法选取大鼠心肌细胞H9c2,根据微小RNA(miR)-340-5p抑制剂及其阴性对照抑制剂转染情况,分为对照组(未处理)、阴性对照抑制剂组和miR-340-5p抑制剂组;根据miR-340-5p抑制剂及其阴性对照抑制剂转染、Dex以及缺氧复氧干预,分为对照组(未处理)、缺氧复氧组、缺氧复氧+Dex组、缺氧复氧+阴性对照抑制剂+Dex组、缺氧复氧+miR-340-5p抑制剂+Dex组;根据miR-340-5p模拟物及其阴性对照模拟物转染、高迁移率族蛋白B1(HMGB1)碱基突变情况,分为HMGB1-wtUTR+阴性对照模拟物组、HMGB1-mutUTR+阴性对照模拟物组、HMGB1-wtUTR+miR-340-5p模拟物组、HMGB1-mutUTR+miR-340-5p模拟物组。采用细胞计数试剂盒8检测细胞增殖水平。采用实时荧光定量聚合酶链反应法检测HMGB1 mRNA、miR-340-5p表达量。采用蛋白质印迹法检测HMGB1、B细胞淋巴瘤2家族蛋白(Bcl-2)、Bcl-2相关X蛋白(Bax)表达量。采用流式细胞术检测细胞凋亡情况。采用双荧光素酶试验验证miR-340-5p与HMGB1的靶向结合。结果缺氧复氧+Dex组miR-340-5p表达量高于缺氧复氧组[(0.80±0.04)比(0.25±0.01)],HMGB1mRNA及其蛋白表达量均低于缺氧复氧组[(1.47±0.13)比(5.02±0.52)、(2.09±0.08)比(4.87±0.16)],差异均有统计学意义(均P<0.05)。缺氧复氧+Dex组细胞增殖水平低于对照组,但高于缺氧复氧组;缺氧复氧+miR-340-5p抑制剂+Dex组细胞增殖水平低于缺氧复氧+阴性对照抑制剂+Dex组;差异均有统计学意义(均P<0.05)。缺氧复氧+miR-340-5p抑制剂+Dex组Bcl-2表达量低于缺氧复氧+阴性对照抑制剂+Dex组,Bax表达量、凋亡率均高于缺氧复氧+阴性对照抑制剂+Dex组,差异均有统计学意义(均P<0.05)。双荧光素酶试验结果显示,HMGB1-wtUTR+阴性对照模拟物组、HMGB1-mutUTR+阴性对照模拟物组、HMGB1-wtUTR+miR-340-5p模拟物组及HMGB1-mutUTR+miR-340-5p模拟物组�Objective To explore the protective effect and mechanism of dexmedetomidine(Dex)on hypoxia/reoxygenation(H/R)-mediated cardiomyocyte apoptosis.Methods Rat cardiomyocytes H9c2 were selected and divided into control group(no intervention),negative-control(NC)inhibitor group and microRNA(miR)-340-5p inhibitor group,according to transfection by miR-340-5p inhibitor or its NC inhibitor.According to miR-340-5p inhibitor or its NC inhibitor transfection,Dex and H/R intervention,H9c2 were divided into control group(no intervention),H/R group,H/R+Dex group,H/R+NC inhibitor+Dex group,H/R+miR-340-5p inhibitor+Dex group.According to miR-340-5p mimic and its NC mimic transfection and high mobility group protein B1(HMGB1)base mutation,H9c2 were divided into HMGB1-wtUTR+NC mimic group,HMGB1-mut UTR+NC mimic group,HMGB1-wtUTR+miR-340-5p mimic group and HMGB1-mutUTR+miR-340-5p mimic group.Cell counting kit-8 was used to detect cells proliferation level,real-time fluorescence quantitative polymerase chain reaction was used to detect expressions of HMGB1 mRNA and miR-340-5p,and western blotting was used to detect the expressions of HMGB1,B cell lymphoma 2(Bcl-2)and Bcl-2-associated X protein(Bax).Flow cytometry was used to detect cell apoptosis.Dual luciferase experiment was used to confirm the direct binding of miR-340-5p to HMGB1.Results The miR-340-5p expression in H/R+Dex group was higher than that in H/R group[(0.80±0.04)vs(0.25±0.01)],and expressions of HMGB1 mRNA and HMGB1 in H/R+Dex group were lower than those in H/R group[(1.47±0.13)vs(5.02±0.52),(2.09±0.08)vs(4.87±0.16)](all P<0.05).Cells proliferation level in H/R+Dex group was lower than that in control group but higher than that in H/R group;that in H/R+miR-340-5p inhibitor+Dex group was lower than that in H/R+NC inhibitor+Dex group(all P<0.05).Bcl-2 expression in H/R+miR-340-5p inhibitor+Dex group was lower than that in H/R+NC inhibitor+Dex group,and Bax expression and apoptosis rate in H/R+miR-340-5p inhibitor+Dex group were higher than those in H/R+NC inhibito

关 键 词：右美托咪定 缺氧复氧损伤 心肌细胞凋亡 微小RNA-340-5p 

分 类 号：R972[医药卫生—药品]