Transcriptional and posttranscriptional regulation of endothelial nitric oxide synthase expression by hydrogen peroxide
Transcriptional and posttranscriptional regulation of endothelial nitric oxide synthase expression by hydrogen peroxide
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DOI：
10.1161/01.res.86.3.347
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发表时间：
2000-02-18
影响因子：
20.1
通讯作者：
Harrison, DG
中科院分区：
文献类型：
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作者：
Drummond, GR;Cai, H;Harrison, DG
各种刺激，包括剪切应力，周期性应变，氧化低密度脂蛋白，高血糖症和细胞生长，调节内皮型一氧化氮合酶（eNOS）的表达。虽然看似无关，但这些都可能改变细胞的氧化还原状态，表明活性氧中间体可能调节eNOS表达。本研究旨在验证这一假设。将牛主动脉内皮细胞暴露于百草枯（一种产生超氧化物（O-2（-））的化合物）24小时，不会影响eNOS mRNA水平。然而，与百草枯和Cu 2 +/Zn 2+超氧化物歧化酶或超氧化物歧化酶模拟物四（4-苯甲酸）卟啉氯化物共处理增加eNOS mRNA的2.3和2.2倍，分别暗示过氧化氢的作用。直接加入100和150 μ mol/L的H2 O2引起牛主动脉内皮细胞eNOS mRNA的增加，这是依赖于浓度（即，3，1-和5.2倍增加）和时间，并相应地提高eNOS蛋白表达和酶活性。核Run-on和5，6-dichloro-1-beta-D-ribofuranosylbenzimidazole-chase研究表明，H2 O2引起eNOS基因转录增加3.0倍，eNOS mRNA半衰期增加2.8倍。羟自由基清除剂DMSO、甘露醇或N-叔丁基-α-苯基硝酮对H2 O2诱导的eNOS无影响，但抗氧化剂N-乙酰半胱氨酸、依布硒啉和外源性过氧化氢酶可抑制H2 O2诱导的eNOS。与H2 O2不同，剪切应力（15 dyne/cm（2），6小时）对eNOS的4.0倍诱导不受N-乙酰半胱氨酸或外源性过氧化氢酶的抑制。结论：H2 O2通过转录和转录后机制促进eNOS表达。虽然H2 O2不介导剪切依赖性eNOS调节，但它可能参与响应于其他生理和/或病理生理刺激的eNOS表达的调节。
Diverse stimuli, including sheer stress, cyclic strain, oxidized LDL, hyperglycemia, and cell growth, modulate endothelial nitric oxide synthase (eNOS) expression. Although seemingly unrelated, these may all alter cellular redox state, suggesting that reactive oxygen intermediates might modulate eNOS expression. The present study was designed to test this hypothesis. Exposure of bovine aortic endothelial cells for 24 hours to paraquat, a superoxide (O-2(-))-generating compound, did not affect eNOS mRNA levels. However, cotreatment with paraquat and either Cu2+/Zn2+ superoxide dismutase or the superoxide dismutase mimetic tetrakis(4-benzoic acid)porphyrin chloride increased eNOS mRNA by 2.3- and 2.2-fold, respectively, implicating a role for H2O2. Direct addition of 100 and 150 mu mol/L H2O2 caused increases in bovine aortic endothelial cell eNOS mRNA that were dependent on concentration (ie, 3,1- and 5.2-fold increases) and time, and elevated eNOS protein expression and enzyme activity, accordingly. Nuclear run-on and 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole-chase studies showed that H2O2 caused a 3.0-fold increase in eNOS gene transcription and a 2.8-fold increase in eNOS mRNA half-life. Induction of eNOS by H2O2 was not affected by the hydroxyl radical scavenger DMSO, mannitol, or N-tert-butyl-alpha-phenylnitrone, but it was inhibited by the antioxidants N-acetylcysteine, ebselen, and exogenously added catalase, Unlike H2O2, the 4.0-fold induction of eNOS by shear stress (15 dyne/cm(2) for 6 hours) was not inhibited by N-acetylcysteine or exogenous catalase. Ln conclusion, H2O2 increases eNOS expression through transcriptional and post-transcriptional mechanisms. Although H2O2 does not mediate shear-dependent eNOS regulation, it is likely to be involved in regulation of eNOS expression in response to other physiological and/or pathophysiological stimuli.