Glutathione redox potential in response to differentiation and enzyme inducers
Glutathione redox potential in response to differentiation and enzyme inducers
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DOI：
10.1016/s0891-5849(99)00145-8
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发表时间：
1999-12-01
影响因子：
7.4
通讯作者：
Jones, DP
中科院分区：
文献类型：
--
作者：
Kirlin, WG;Cai, JY;Jones, DP
还原型谷胱甘肽（GSH）/氧化型谷胱甘肽（GSSG）氧化还原状态被认为在解毒基因表达的信号传导中起作用，但在正常条件下在细胞中似乎也受到严格调控。因此，目前尚不清楚的是，在响应生理刺激的变化的幅度是足够的氧化还原信号在非毒理学条件下的作用。本研究的目的是确定2GSH/GSSG氧化还原过程中的分化和解毒酶活性增加的信号在HT 29细胞中的变化。我们测量了GSH，GSSG，细胞体积和细胞pH值，我们用能斯特方程来确定氧化还原电位E-h的变化，响应分化剂，丁酸钠，解毒酶诱导剂，异硫氰酸苄酯的2GSH/GSSG池。丁酸钠引起60 mV氧化（从-260 mV至-200 mV），该氧化足以使蛋白质二硫醇：二硫化物比例发生100倍变化。异硫氰酸苄酯在对照细胞中引起16 mV氧化，但在分化细胞中引起40 mV氧化（至-160 mV）。谷胱甘肽和谷氨酸：半胱氨酸连接酶mRNA的变化与E-h无关;然而，E-h与谷胱甘肽S-转移酶（GST）和烟酰胺腺嘌呤二核苷酸磷酸（NADPH）：醌还原酶活性（N：QR）之间存在相关性。这些结果表明，2GSH/GSSG氧化还原变化响应生理刺激，如分化和酶诱导剂是一个足够的幅度来控制氧化还原敏感蛋白的活性。这表明，2GSH/GSSG氧化还原平衡的生理调节可以为控制细胞表型提供基本参数。(C)1999年，Elsevier Science。
The reduced glutathione (GSH)/oxidized glutathione (GSSG) redox state is thought to function in signaling of detoxification gene expression, but also appears to be tightly regulated in cells under normal conditions. Thus it is not clear that the magnitude of change in response to physiologic stimuli is sufficient for a role in redox signaling under nontoxicologic conditions. The purpose of this study was to determine the change in 2GSH/GSSG redox during signaling of differentiation and increased detoxification enzyme activity in HT29 cells. We measured GSH, GSSG, cell volume, and cell pH, and we used the Nernst equation to determine the changes in redox potential E-h, of the 2GSH/GSSG pool in response to the differentiating agent, sodium butyrate, and the detoxification enzyme inducer, benzyl isothiocyanate. Sodium butyrate caused a 60-mV oxidation (from -260 to -200 mV), an oxidation sufficient for a 100-fold change in protein dithiols:disulfide ratio. Benzyl isothiocyanate caused a 16-mV oxidation in control cells but a 40-mV oxidation (to -160 mV) in differentiated cells. Changes in GSH and mRNA for glutamate:cysteine ligase did not correlate with E-h; however, correlations were seen between E-h and glutathione S-transferase (GST) and nicotinamide adenine dinucleotide phosphate (NADPH):quinone reductase activities (N:QR). These results show that 2GSH/GSSG redox changes in response to physiologic stimuli such as differentiation and enzyme inducers are of a sufficient magnitude to control the activity of redox-sensitive proteins. This suggests that physiologic modulation of the 2GSH/GSSG redox poise could provide a fundamental parameter for the control of cell phenotype. (C) 1999 Elsevier Science.