VEGF protects bovine aortic endothelial cells from TNF-α-and H_2O_2-induced apoptosis via co-modulatory effects on p38- and p42 p44-CCDPK signaling  

VEGF通过对p38和p42/p44 CCDPK信号的共调节作用抑制TNF-α和H_2O_2诱导的牛主动脉内皮细胞凋亡(英文)

作　　者：刘文兰[1] 郭迅[1] 陈清泉 郭兆贵[1] 

机构地区：[1]中南大学湘雅医学院分子药理研究室,长沙中国410078

出　　处：《Acta Pharmacologica Sinica》2002年第1期45-49,共5页中国药理学报（英文版）

摘　　要：To investigate the effect of VEGF on TNF-α-or H2O2 induced apoptosis in cultured bovine aortic endothelial cells (BAEC) and the underlied signal trans-duction mechanisms related to Ca2+ -calmodulin dependent protein kinase (CCDPK). METHODS: BAEC were cultured and passaged in DMEM. Morphologic changes and quantification of apoptotic cells were determined under fluorescence microscope with Hoechst 33258 staining. Cell viability was detected with MTT method. DNA fragmentation was visualized by agarose gel electrophoresis. The expression of phospho-p38 and phospho-p42/p44 CCDPK was measured by Western blotting. RESULTS: TNF-α5000 kU/L and H2O2 300 μmol/L elicited DNA fragmentation in BAEC. Vascular endothelial growth factor (VEGF) 100 μg/L significantly protected BAEC from apoptosis induced by TNF-α or H2O2, as shown in cell viability assay and apoptotic cell counting. DNA fragmentation induced by TNF-αor H2O2 was also reduced by VEGF 100 μg/L. VEGF enhanced TNF-αand H2O2 stimulated expression of phospho-p42/p44 CCDPK, simultaneously inhibited TNF-α-and H2O2-induced activation of phospho-p38 CCDPK. Both the VEGF-induced up-regulation of phospho-p42/p44 CCDPK and its anti-apoptotic action were prevented by the specific p42/p44 CCDPK inhibitor U0126. CONCLUSION: VEGF protects BAEC from apoptosis induced by TNF-αand H2O2, and its co-modulatory effects by activation of p42/p44 CCDPK signaling together with inhibition of p38 CCDPK signaling appear to be an important mechanism for its survival effect on endothelial cells.目的:研究血管内皮细胞生长因子(VEGF)对肿瘤坏死因子(TNF-α)和过氧化氢(H_2O_2)诱导生主动脉内皮细胞(BAEC)凋亡的影响及信号机制.方法:BAEC培养并传代于DMEM.经TNF-α或H^2O_2处理24h后,Hoechst 33258染色,荧光显微镜观察形态学变化及凋亡细胞计数.MTT法测定细胞活性,琼脂糖凝胶电泳分析DNA降解,Western blot法检测磷酸化p^(38)和p^(42)/p^(44) CCDPK表达.结果:TNF-α5000kU/L和H_2O_2 300μmol/L均可诱导BAEC产生DNA断片.VEGF 100 μg/L显著增强TNF-α和H_2O_2诱导的磷酸化p^(42)/p^(44) CCDPK表达,而明显抑制磷酸化 p^(38) CCDPK的活化.对二者所致 BAEC凋亡起明显的抑制作用.P^(42)/p^(44) CCDPK抑制剂U0126可取消 VEGF引起的磷酸化p^(42)/p^(44) CCDPK表达上调和其抗凋亡作用.结论:VEGF通过其共调节作用激活p^(42)/p^(44) CCDPK,抑制p^(38) CCDPK信号途径而对TNF-α和H_2O_2所致凋亡产生的抑制效应,是内皮细胞存活的重要机制.

关 键 词：apoptosis DNA fragmentation Ca2+-calmodulin dependent protein kinase tumor necrosis factor hydrogen peroxide endothelial growth factors Western blotting vascular endothelium cultured cells 

分 类 号：Q51[生物学—生物化学]