AngⅡ诱导血管内皮细胞衰老及凋亡相关基因的表达  

Senescence of endothelial cells and gene expression associated with apoptosis induced by angiotensinⅡ

作　　者：单海燕[1] 白小涓[1] 张四扬[2] 陈香美[3] 

机构地区：[1]中国医科大学第一附属医院循环内科,辽宁沈阳110001 [2]中国医科大学病理教研室,辽宁沈阳110001 [3]中国人民解放军总院肾病中心,北京100853

出　　处：《中国病理生理杂志》2008年第6期1041-1046,共6页Chinese Journal of Pathophysiology

基　　金：国家973重点基础研究发展规划资助项目(NoG2007CB507405);辽宁省教育厅高等学校科学研究资助项目(No05L470)

摘　　要：目的:探讨血管紧张素Ⅱ(AngⅡ)诱导人脐静脉内皮细胞(HUVECs)衰老及凋亡相关基因Bcl-2、Bax的表达。方法:体外培养人脐静脉内皮细胞,采用四甲基偶氮唑蓝比色法测定内皮细胞存活率,用AngⅡ(10-6mol/L)及valsartan(AngⅡ1型受体特异性拮抗剂)干预,分为实验对照组、AngⅡ诱导组及valsartan组,采用β-半乳糖苷酶染色和流式细胞术鉴定细胞衰老,通过Hoechst33258荧光染色观察细胞形态学变化,并利用免疫细胞化学染色法、RT-PCR法和Western blotting分析各组细胞凋亡相关基因Bcl-2、Bax mRNA及蛋白的表达水平。结果:与对照组相比,10-6mol/LAngⅡ诱导组存活的细胞数为对照组的(81.90±0.04)%;(80.10±6.81)%的细胞呈现β-半乳糖苷酶阳性染色。流式细胞仪检测细胞周期停滞于G0-G1[(91.36±6.45)%],证实细胞衰老;荧光显微镜可见明显的细胞凋亡[(31.84±2.86)%]。与AngⅡ诱导组相比,valsartan组Bcl-2mRNA及蛋白表达水平明显增高(P<0.05),Bax mRNA及蛋白表达水平降低(P<0.05)。结论:AngⅡ可诱导体外培养的HUVECs老化。经AngⅡ诱导的衰老HUVECs发生凋亡,提示细胞凋亡参与了AngⅡ诱导HUVECs细胞的衰老过程。AngⅡ诱导血管内皮细胞衰老的分子机制之一可能与Bcl-2、Bax mRNA及蛋白表达的失衡有关。缬沙坦对血管内皮细胞衰老有一定保护作用。AIM： To study the senescence of human umbilical vein endothelial cells （HUVECs） and Bcl -2, Bax gene expression associated with apoptosis induced by angiotensin H （ Ang H ）. METHODS： HUVECs were cultured in vitro and the cell viability was observed by methyl thiazolyl tetrazolium （MTT）. HUVECs were intervened by Ang H and valsartan （ Ang H type 1 receptor blocking） and divided into 3 groups： the control group, Ang H group （ stimulated with Ang H 10 ^-6mol/L for 48 h）, valsartan group （ valsartan was added to cells 1 h before 10^-6mol/L Ang H treatment）. β-gal staining and cell cycle analysis were used to identify the cell aging status. Morphologic changes and percentage of apoptosis were assayed with Hoechst33258 under fluorescent microscope. The expressions of Bcl - 2 and Bax, and the apeptosis - associated genes were detected by immunocytochemical staining, RT-PCR and Western blotting. RESULTS： The cell viability by Ang H-induced cells was （81.9%±4. 1 ）% , the positive cell number of 13 - gal staining was significantly higher in Ang H - induced cells （80. 10%±6. 81 ）% than that in the control cells. The cell cycle was at Go - G, （91.36%±6.45） %, the apeptotic cells significantly increased （ 31.84±2. 86） % under fluorescent microscope. In valsartan group. Bcl - 2 mRNA and protein expression increased markedly （ P 〈 0.05）. but Bax mRNA and protein expres- sion decreased evidently （ P 〈 0. 05 ） compared to those in the Ang II group. CONCLUSION ： Cell apoptosis is possibly an important factor for endothelial cell senescence and vascular aging induced by Ang II. One of its molecular mechanisms might be associated with decreasing the expression level of Bcl -2 and increasing that of Bax, which regulate the imbalance between mRNA and protein expression of Bcl -2 and Bax. Valsartan improves endothelial cell aging.

关 键 词：血管紧张素II 脐静脉内皮细胞 血管衰老 细胞凋亡 基因 BCL-2 基因 Bax蛋白质 BCL-2 蛋白质 Bax 

分 类 号：R339.38[医药卫生—人体生理学]