摘要
目的 阐明次氯酸修饰白蛋白(HOC1-Alb)诱导血管内皮细胞炎性反应的机制.方法 用体外制备的HOCl-Alb与人脐静脉内皮细胞共同培养;用光泽精增强化学发光法测定NADPH氧化酶活性;用免疫沉淀和Western印迹法测定p47phox磷酸化及p47phox与p22phox结合;用免疫荧光化学染色法观察p47phox膜迁移;分别用RT-PCR和Western印迹法测定细胞间黏附分子1(ICAM-1)mRNA和蛋白表达.为了解NADPH氧化酶在HOCl-Alb上调ICAM-1表达过程中的作用,在HOCl-Alb刺激细胞前,在细胞培养液中预先加入NADPH氧化酶特异性抑制剂夹竹桃麻素(apocynin),观察ICAM-1表达的变化.结果 HOCl-Alb激活NADPH氧化酶具有剂量和时间依赖性,200 mg/L HOCl-Alb刺激15 min使NADPH氧化酶活性增加的量是牛血清白蛋白组的6.16倍(P<0.01),并可诱导p47phox磷酸化和膜迁移,及其与p22phox结合.HOCl-Alb上调ICAM-1表达的作用可被夹竹桃麻素抑制,500μmol/L夹竹桃麻素对HOCl-Alb诱导的ICAM-1表达的抑制率为68.97%(P<0.01).结论 NADPH氧化酶是HOCl-Alb诱导ICAM-1高表达的重要途径,与血管内皮炎性反应关系密切.
Objective To elucidate the mechanism of inflammation in vascular endothelial cells induced by hypochlorite-modified albumin (HOCl-Alb). Methods HOCl-Alb-induced NADPH oxidase activity in human umbilical vein endothelial cells (HUVEC) was measured by lucigenin-enhanced chemiluminescence. Phosphorylation of p47phox and binding of p47phox and p22phox were measured with immunoprecipitation and Western blotting. Membrane translocation of p47phox was measured with immunofluorescence. RT-PCR and Western blotting were used to determine the intercellular adhesion molecule-1 (ICAM-1) mRNA and protein expression in the presence or absence of apocynin, respectively. Results Co-incubation of HUVEC with HOClAlb resulted in the enhancement of NAIDPH oxidase activity in time- and dose-dependent manner.Compared with bovine serum albumin group, exposure of the cells with 200 mg/L HOCl-Alb for 15min resulted in a 6.16-fold increase in NADPH oxidase activity. Phosphorylation and membrane translocation of p47phox and binding of it with p22phox were also induced by HOCl-Alb. ICAM-1expression was up-regulated after exposure to HOCl-Alb and this effect was significantly abolished by apocynin, a specific inhibiter of NADPH oxidase, in dose-dependent manner. Preincubation of the cells with 500 μmol/L apocynin inhibited the expression of ICAM-1 protein induced by HOClAlb by 68.97% (P〈0.01). Conclusion NADPH oxidase plays a central role in HOCl-Albmediated ICAM-1 expression and provides a mechanism for HOCl-Alb-related vascular endothelial inflammation.
出处
《中华肾脏病杂志》
CAS
CSCD
北大核心
2010年第9期683-688,共6页
Chinese Journal of Nephrology
基金
广东省自然科学基金(9451051501002540)
关键词
次氯酸
白蛋白类
糖尿病
内皮功能失常
Hypochlorous acid
Albumins
Diabetes mellitus
Endothelial dysfunction