银杏叶提取物对TNF-α诱导的牛主动脉内皮细胞血凝素样氧化低密度脂蛋白受体表达的影响及其机制

Extract of Ginkgo Biloba decreased expression of lectin-like oxidized low density lipoprotein receptor-1 induced by TNF-α in bovine aortic endothelial cells

目的:研究银杏叶提取物(EGB)对肿瘤坏死因子-α(TNF-α)诱导的牛主动脉内皮细胞(BAECs)血凝素样氧化低密度脂蛋白受体-1(LOX-1)表达的影响及其机制。方法:分离培养BAECs,应用TNF-α诱导BAECs表达LOX-1,给予EGB刺激,采用RT-PCR以及W estern b lotting的方法检测BAECs LOX-1表达的改变,同时用W estern b lotting检测内皮型一氧化氮合酶(eNOS)蛋白表达的变化,检测细胞培养液中亚硝酸盐(NO2-/NO3-)的含量。结果:TNF-α显著上调LOX-1的表达(P<0.05),EGB显著抑制TNF-α诱导的LOX-1的表达(P<0.05),而一氧化氮合酶抑制剂可显著抑制EGB的效应(P<0.05);TNF-α显著下调eNOS的表达(P<0.05),EGB显著促进eNOS蛋白的表达(P<0.05);TNF-α明显降低亚硝酸盐(NO2-/NO3-)的含量(P<0.05),EGB显著抑制TNF-α诱导的亚硝酸盐(NO2-/NO3-)含量的降低(P<0.05)。结论:EGB显著抑制TNF-α诱导的LOX-1的表达,其作用由EGB上调的NO介导。

AIM：To investigate the effects of extract of Ginkgo biloba（EGB） on the expression of lectin-like oxidized low-density lipoprotein receptor-1（LOX-1） induced by tumor necrosis factor a（TNF-α） in bovine aortic endothelial cells（BAECs）.METHODS： The BAECs were incubated with TNF-α,followed by EGB treatment.The effect of EGB on LOX-1 expression was investigated by RT-PCR and Western blotting.The content of endothelial nitric oxide synthase（eNOS） was determined by Western blotting.Potential involvement of signaling pathways of the effects was explored by using related inhibitors of the signal molecules.The concentration of NO-2/NO-3 was also tested.RESULTS： Increased LOX-1 expression was induced by TNF-α.EGB markedly prevented the increase of LOX-1 expression induced by TNF-α（P0.05）,and this effect was inhibited by inhibitor of NOS（P0.05）.EGB significantly prevented the decrease of eNOS expression induced by TNF-α（P0.05）.EGB also significantly prevented the decrease of NO-2/NO-3 production induced by TNF-α（P0.05）.CONCLUSION： EGB markedly prevents the increase of LOX-1 expression induced by TNF-α and the effect is mediated by eNOS.