缺氧后处理与氧自由基清除剂预处理对心肌细胞膜和线粒体Bcl-2和Bax表达的影响  

Effect of postconditioning and free radical scavengers on expression of Bcl-2 and Bax proteins in cardiomyocytes and mitochondria

作　　者：涂荣会[1] 钟国强[1] 曾志羽[1] 陈立[2] 何艳[2] 黎庆捷[2] 梁艺 

机构地区：[1]广西医科大学第一附属医院心血管病研究所老年心内科,南宁530000 [2]广西医科大学第一附属医院心血管病研究所心内科,南宁530000

出　　处：《中华老年心脑血管病杂志》2012年第3期294-297,共4页Chinese Journal of Geriatric Heart,Brain and Vessel Diseases

基　　金：国家自然科学基金(30960131)

摘　　要：目的观察缺氧后处理与氧自由基清除剂超氧化物歧化酶(SOD)联合过氧化氢酶(CAT)预处理,对心肌细胞膜和线粒体Bcl-2、Bax蛋白表达的影响,探讨两者调控心肌细胞凋亡的机制。方法建立乳鼠心肌细胞缺氧/复氧损伤模型,分对照组、缺氧/复氧组、缺氧后处理组及缺氧/复氧+SOD+CAT组。应用荧光探针测定心肌细胞线粒体活性氧水平,Hoechst染色及流式细胞仪检测心肌细胞凋亡,Wesiern blot法检测心肌细胞膜和线粒体Bcl-2、Bax蛋白表达。结果与对照组比较,缺氧/复氧组、缺氧后处理组、缺氧/复氧+SOD+CAT组细胞线粒体活性氧及细胞凋亡率明显升高(P<0.01);与缺氧/复氧组比较,缺氧后处理组、缺氧/复氧+SOD+CAT组细胞线粒体活性氧及细胞凋亡率明显降低(P<0.01);缺氧后处理组及缺氧/复氧+SOD+CAT组细胞膜和线粒体Bcl-2蛋白明显上调,Bax蛋白明显下调。结论缺氧后处理及氧自由基清除剂预处理抑制线粒体活性氧爆发,减轻缺氧/复氧再灌注心肌细胞凋亡,其抗凋亡可能机制与细胞膜和线粒体Bcl-2蛋白表达上调及Bax蛋白表达下调有关。Objective To observe the effect of postconditioning and free radical scavengers,superoxide dismutase（SOD）and catalase（CAT）,on expression of Bcl-2 and Bax proteins in cardiomyocytes and mitochondria,and study the machinism of Bcl-2 and Bax underlying apoptosis of cardiomyocytes. Methods A hypoxia（H）/reoxygenation（R） model of suckling mouse cardiomyocytes was established. The suckling mouse cardiomyocytes were divided into control group, H/R group, postconditioning（PC） and H/R＋SOD＋CAT group. Mitochondrial reactive oxygen species（ROS） in cardiomyocytes and mitochondria were detected with fluorescence probes. Apoptosis of cardio- myocyte was assayed by flow cytometry with Hoechst 33342 staining. Expressions of Bcl-2 and Bax proteins in cardiomyocytes and mitochondria were detected by Western blot. Results The number of mitochondrial ROS and apoptotic cardiomyocytes was significantly less in PC group and H/R＋SOD＋CAT group than in H/R group[28.59±2.93 and 28.43±1.76 vs 58. 19±3.29,（26.99±3.35）% and （26.45±5.08）% vs （45.86±3.29）%,P〈0.01]. The Bcl-2 expression level was higher while the Bax expression level was lower in PC group and H/R-＋-SOD＋ CAT group than in H/R group. Conclusion Postconditioning and free radical scavengers reduce hypoxia while reoxygenation induces apoptosis of cardiomyocytes by upregulating the Bcl-2 expression and down-regulating the Bax expression in cardiomyocytes and mitochondria.

关 键 词：肌细胞 心脏 缺氧 活性氧 自由基清除剂 细胞膜 线粒体 心脏 超氧化物歧化酶 细胞凋亡 

分 类 号：R363[医药卫生—病理学]