Shear stress inhibits H2O2-induced apoptosis of human endothelial cells by modulation of the glutathione redox cycle and nitric oxide synthase
Shear stress inhibits H2O2-induced apoptosis of human endothelial cells by modulation of the glutathione redox cycle and nitric oxide synthase
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DOI：
10.1161/01.atv.17.12.3588
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发表时间：
1997-12-01
影响因子：
8.7
通讯作者：
Dimmeler, S
中科院分区：
文献类型：
--
作者：
Hermann, C;Zeiher, AM;Dimmeler, S
生理水平的剪切应力可减少内皮细胞的更新，并发挥有效的抗动脉粥样硬化作用。在这里，我们证明了氧化应激诱导的人内皮细胞凋亡受到剪切应力（15 dynes/cm(2)）的抑制。与H2O2 （200 μ mol/L）孵育18小时可诱导人脐静脉内皮细胞凋亡，这可以通过组蛋白相关DNA片段特异性酶联免疫吸附试验和荧光染色细胞核的视觉分析来证明。丁硫氨酸亚砜（BSO）或n - g -单甲基- l-精氨酸（LNMA）抑制谷胱甘肽（GSH）生物合成可部分阻止应激介导的细胞凋亡抑制，而氨三唑对过氧化氢酶的抑制不影响剪切应激的抑制作用。联合抑制NO合成酶和谷胱甘肽的生物合成完全逆转了单纯应激的保护作用。提示NO合成酶和谷胱甘肽氧化还原循环系统参与了应激对细胞凋亡的抑制作用。当肿瘤坏死因子α (TNF α)刺激细胞凋亡时，也获得了类似的结果。为了进一步了解剪切应力对凋亡信号转导的干扰，我们测量了caspase-3样活性，caspase-3是一种半胱氨酸蛋白酶，已被证明在细胞死亡效应途径中起主要作用。事实上，剪切应力阻止了H2O2或TNF α诱导的caspase-3样活性的激活。LNMA和BSO可抑制剪切应力的抑制作用。提示剪切应力减少氧化通量可阻止caspase样蛋白酶的激活，从而抑制人内皮细胞凋亡细胞死亡。
Physiological levels of shear stress reduce endothelial cell turnover and exert a potent antiatherosclerotic effect. Here we demonstrate that oxidative stress-induced apoptosis of human endothelial cells was inhibited by shear stress (15 dynes/cm(2)). incubation with H2O2 (200 mu mol/L) for 18 hours induced apoptosis of human umbilical venous endothelial cells as demonstrated by an enzyme-linked immunosorbent assay specific for histone-associated DNA fragments and visual analysis of fluorescence-stained nuclei. Sheer stress-mediated inhibition of apoptosis was partially prevented by pharmacological inhibition of glutathione (GSH) biosynthesis with buthionine sulfoximine (BSO) or nitric oxide (NO) synthase with N-G-monomethyl-L-arginine (LNMA), whereas inhibition of catalase by aminotriazol did not affect the inhibitory action of shear stress. Combined inhibition of NO synthase and GSH biosynthesis completely reversed the protective effect of sheer stress. suggesting that bath NO synthase and the GSH redox cycle system are involved in the apoptosis-suppressing effect of sheer stress. Similar results were obtained when apoptosis was stimulated by tumor necrosis factor alpha (TNF alpha). To gain further insights into the interference of shear stress with apoptosis signal transduction, we measured caspase-3-like activity, a cysteine protease that has been shown to play a predominant role in the cell death effector pathway. Indeed, shear stress prevented the activation of caspase-3-like activity induced by H2O2 or TNF alpha. The inhibitory effect of shear stress was prevented by LNMA and BSO. suggesting that the reduction of oxidative flux by shear stress prevents the activation of caspase-like proteases and thereby inhibits apoptotic cell death in human endothelial cells.