REGULATION OF ETHANOL-INDUCIBLE CYTOCHROME P450 GENE

乙醇诱导细胞色素 P450 基因的调控

• 批准号: 3801921
• 负责人: B J SONG
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON ALCOHOL ABUSE AND ALCOHOLISM
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3801921
• 关键词: alcoholism /alcohol abuse; aniline; cytochrome P450; enzyme induction /repression; enzyme mechanism; enzyme structure; enzyme substrate; ethanol; free radicals; genetic transcription; human tissue; isozymes; ketone body; laboratory rat; lymphocyte; messenger RNA; posttranslational modifications; tissue /cell culture; western blottings

As a continuous ongoing project, the molecular regulatory mechanism of P450IIE was further investigated. We have previously identified and determined the structures of the ethanol-inducible cytochrome P450 (P450IIE) of both rat and human. We have also demonstrated three distinct types of regulation of P450IIE. The mechanism of P450IIE mRNA stabilization was further studied to identify intermediary metabolites responsible for the mRNA stabilization. The level of two ketone bodies (~-hydroxybutyrate and acetoacetate) positively correlated with the elevated level of P450IIE mRNA. In addition, the molecular mechanism of P450IIE reduction by CCl4, was also examined. Aniline hydroxylase and the amounts of immunoreactive P450IIE were rapidly decreased in a time-dependent manner after CCl4 injection. These declines were not accompanied by the changes in the level of P450IIE mRNA and transcriptional activity, indicating a post-translational inhibition by CCl probably due to specific destruction of P450IIE by locally generated free radical metabolites. In contrast, the amounts of immunoreactive other P450s such as P450IA and P450IIC did not appear to be affected by CCl4, indicating a specific destruction of P450IIE by its substrate. A method for the measurement of P450IIE in easily obtainable human tissues was also established. P450IIE1 expressed in cultured lymphocytes could be easily detected by specific antibody to P450IIE. The induction of lymphocyte P450IIE was observed in both human and rat lymphocytes. The levels of P450IIE in lymphocytes from alcoholic patients at admission and discharge are being studied.

作为一个持续正在进行的项目，分子调节机制 P450IIE进一步研究了。我们以前已经确定了 确定乙醇诱导的细胞色素P450的结构 （p450iie）的大鼠和人。 我们还展示了三个 P450IIE的不同类型。 P450IIE mRNA的机制 进一步研究了稳定以鉴定中间代谢物 负责mRNA稳定。 两个酮体的水平 （〜-羟基丁酸和乙酸乙酸酯）与 P450IIE mRNA的升高水平。另外，分子机制 还检查了CCL4减少P450IIE。 苯胺羟化酶和 在A中，免疫反应性P450IIE的量迅速减少 CCL4注射后的时间依赖性方式。这些下降不是 伴随着P450IIE mRNA和 转录活性，表明CCL的翻译后抑制 可能是由于本地生成的P450IIE的特定破坏 自由基代谢物。相反，免疫反应性的量 其他P450（例如P450IA和P450IIC）似乎没有受到影响 通过CCL4，表明其底物对P450IIE进行了特定的破坏。 一种在易于获得的人类中测量P450IIE的方法 还建立了组织。 P450IIE1在培养中表达 淋巴细胞可以通过对P450IIE的特异性抗体轻松检测。 在人类和 大鼠淋巴细胞。 酒精淋巴细胞中P450IIE的水平 正在研究入院和出院时的患者。