Glutathione depletion induces apoptosis of rat hepatocytes through activation of protein kinase C novel isoforms and dependent increase in AP-1 nuclear binding
- 作者：Domenicotti ; Cinzia ; Paola ; Dimitri ; Vitali ; Antonella ; Nitti ; Mariapaola ; d’ ; Abramo ; Cristina ; et. al.
- 关键词：Oxidative stress ; Glutathione ; Protein kinase C isoforms ; Nuclear transcription factors ; Apoptosis ; Free radicals ; PKC ; protein kinase C ; GSH ; reduced glutathione ; AP-1 ; activator protein-1 ; BSO ; L-buthionine-S ; R-sulfoximine ; DEM ; maleic acid diethylester
- 刊名：Free Radical Biology and Medicine
- 出版年：2000
- 期刊代码：105_08915849
- 类别：med
- 出版时间：December 15, 2000
- 卷：29
- 期：1
- 页码：1280-1290
- 文件大小：919 K
摘要
Treatment of isolated rat hepatocytes with the glutathione depleting agents L-buthionine-S,R-sulfoximine or diethylmaleate reproduced various cellular conditions of glutathione depletion, from moderate to severe, similar to those occurring in a wide spectrum of human liver diseases. To evaluate molecular changes and possible cellular dysfunction and damage consequent to a pathophysiologic level of GSH depletion, the effects of this condition on protein kinase C (PKC) isoforms were investigated, since these are involved in the intracellular specific regulatory processes and are potentially sensitive to redox changes. Moreover, a moderate perturbation of cellular redox state was found to activate novel PKC isoforms, and a clear relationship was shown between novel kinase activation and nuclear binding of the redox-sensitive transcription factor, activator protein-1 (AP-1). Apoptotic death of a significant number of cells, confirmed in terms of internucleosomal DNA fragmentation was a possible effect of these molecular reactions, and was triggered by a condition of glutathione depletion usually detected in human liver diseases. Finally, the inhibition of novel PKC enzymatic activity in cells co-treated with rottlerin, a selective novel kinase inhibitor, prevented glutathione-dependent novel PKC up-regulation, markedly moderated AP-1 activation, and protected cells against apoptotic death. Taken together, these findings indicate the existence of an apoptotic pathway dependent on glutathione depletion, which occurs through the up-regulation of novel PKCs and AP-1.