缺氧后处理对缺氧复氧心肌线粒体活性氧及细胞凋亡的影响  

Effects of Hypoxia Postconditioning on Mitochondrial Reactive Oxygen Species and Cardiomyocyte Apoptosis Induced by Hypoxia/Reoxygenation

作　　者：涂荣会[1] 钟国强[1] 曾志羽[1] 陈立[1] 何艳[1] 黎庆捷[1] 梁艺 

机构地区：[1]广西医科大学第一附属医院老年心内科,广西南宁市530000

出　　处：《中国动脉硬化杂志》2012年第6期499-502,共4页Chinese Journal of Arteriosclerosis

基　　金：国家自然科学基金(30960131)资助

摘　　要：目的观察缺氧后处理对缺氧复氧心肌线粒体活性氧及细胞膜和线粒体Bcl-2和Bax蛋白表达的影响,探讨其调控心肌细胞凋亡的机制。方法构建大鼠乳鼠心肌细胞缺氧复氧损伤模型,将细胞分为对照组、缺氧/复氧组(缺氧3 h后复氧6 h)、缺氧后处理组(缺氧3 h后行复氧5 min、缺氧5 min,反复3次,再复氧6 h)。应用荧光酶标仪测定线粒体活性氧量,流式细胞仪检测心肌细胞凋亡,Western blot检测细胞膜和线粒体Bcl-2和Bax蛋白的表达。结果缺氧/复氧组和缺氧后处理组心肌细胞线粒体活性氧量较对照组显著升高(P<0.01)。缺氧后处理组心肌细胞线粒体平均荧光强度为30.74±1.88 a.u./μg,显著低于缺氧/复氧组(63.17±2.75 a.u./μg,P<0.01),仍高于对照组(14.41±2.15 a.u./μg)。缺氧/复氧组和缺氧后处理组心肌细胞凋亡率较对照组显著升高(45.86%±3.29%和26.99%±3.35%比5.72%±1.63%,P<0.01),缺氧后处理组低于缺氧/复氧组(P<0.01)。细胞膜和线粒体Bcl-2蛋白在缺氧后处理组显著上调,在缺氧/复氧组显著下调;Bax蛋白在缺氧后处理组显著下调,在缺氧/复氧组显著上调。结论缺氧后处理抑制线粒体活性氧爆发,减轻缺氧/复氧诱导的心肌细胞凋亡,其抗凋亡机制可能与线粒体和细胞膜Bcl-2蛋白表达上调及Bax蛋白表达下调有关。Aim To investigate the effect of hypoxia postconditioning on mitochondrial reactive oxygen species（ROS） and cardiomyocyte apoptosis induced by hypoxia/reoxygenation.Methods The model of cultured cardiomyocytes with hypoxia/reoxygenation（H/R） was established and the cardiomyocytes were divided into 3 groups,including control group,H/R group（hypoxia 3 h and reoxygenation 6 h）,and hypoxia postconditioning（PC） group（3 intermittent cycles of 5 min H/R immediately after hypoxia 3 h,then reoxygenation for 6 h）.Cardiac mitochondria and sarcolemma were isolated by differential centrifugation.ROS was detected with fluorescent probes and cardiomyocyte apoptosis was detected with flow cytometry.The expressions of Bcl-2 and Bax proteins in the cardiac mitochondria and sarcolemma were measured by Western blot.Results Both mitochondrial ROS and the number of apoptotic cardiomyocytes reduced significantly in PC group compared with H/R group.Bcl-2 levels increased while Bax levels decreased in cardiac mitochondria and sarcolemma of PC group.ConclusionPC attenuated ROS and cardiomyocyte apoptosis induced by H/R,which potentially mediated by upregulating the expression of Bcl-2 and downregulating the Bax in mitochondria and sarcolemma.

关 键 词：缺氧后处理 活性氧 缺氧/复氧 细胞凋亡 

分 类 号：R363[医药卫生—病理学]