免疫性肝损伤过程中细胞色素P450酶系下调的转录水平调节和翻译后蛋白修饰研究

In the process of immunological liver injury, the superfamily of drug metabolizing enzymes has been down-regulation, but whether it is the cause or the result of liver injury is an intense debate now. Bacille Calmette-Guerin (BCG) immune stimulation mouse or rats model was employed in this study by in vivo or invitro, in order to observe the effection of immunity liver injury on CYP450s of protein content , protein expression ,metabolism activity and gene regulation. Furthermore, to observe the effection of nuclear factor-κB（NF-κB）and nuclear receptor(PXR ,AhR) on CYP450s of protein content , expression ,metabolism activity. At the same time to try to find out the effect of whether or not the expression of CYP450s were regulated by nuclear factor kB and nuclear receptor by activation or inhibition NF-κB and PXR. To observe the effects of posttranslational modification on the activity of cytochrome P450s, drugs use as a tool to regulation the modification above-mentioned. This study aimed at questing for CYP450 family regulation availability and transcriptional control and post-translational modification link and target in the conditions of immunity liver injury and providing experiment groundwork for reasonable medication in clinical. This work would provid pharmacology evidence for curing chronicity immunity Hepatic injury .

免疫性肝损伤过程中，细胞色素P450药物代谢酶系（CYP450s）下调，引起药物反应异常和药物相互作用，CYP450s的变化及其调控在损伤机制中起重要作用，但其下调机制尚未明确。本课题采用卡介苗（BCG）诱发小鼠或大鼠产生免疫损伤性损伤，在整体 (in vivo)水平或体外细胞培养(in vitro)水平，深入探讨免疫损伤性过程中核因子（NF-κB）和核受体（孕烷X 受体，PXR；芳香烃受体，AhR）与CYP450s含量、蛋白表达、代谢活力的关系；使用工具药调控核因子与核受体探讨CYP450s转录调节机制；观察免疫性肝损伤过程中CYP450s蛋白磷酸化、硝基化、泛素化等翻译后修饰机制，使用工具药干预上述修饰，观察对CYP450s的影响，探讨可否通过干预转录调节和翻译后修饰机制影响CYP450代谢途径进行调控缓解免疫损伤性肝炎，为肝病的药物提供新的思路和靶点。

免疫性肝损伤过程中，细胞色素P450药物代谢酶系（CYP450s）下调，引起药物反应异常和药物相互作用，CYP450s的变化及其调控在损伤机制中起重要作用，但其下调机制尚未明确。本课题采用卡介苗诱发小鼠或大鼠产生免疫损伤性损伤，在整体 (in vivo)水平或体外细胞培养(in vitro)水平，深入探讨了免疫损伤性过程中核因子（NF-κB）和核受体（孕烷X 受体，PXR；芳香烃受体，AhR）与CYP450s含量、蛋白表达、代谢活力的关系；使用工具药调控核因子与核受体探讨CYP450s转录调节机制；观察了免疫性肝损伤过程中CYP450s蛋白磷酸化、硝基化、泛素化等翻译后修饰机制，使用工具药干预上述修饰，观察对CYP450s的影响，探讨通过干预转录调节和翻译后修饰机制影响CYP450代谢途径进行调控缓解免疫损伤性肝炎，为肝病的药物提供新的思路和靶点。重要结果与关键数据：BCG免疫刺激可致小鼠或大鼠产生以肝脏肿大，炎性细胞大量浸润，肝功能受损为特征的免疫性肝损伤模型，导致四种主要在肝脏表达的CYP450亚型蛋白表达或代谢活性下调。CYP450的转录调节受到NF-κB、PXR表达的调控，免疫损伤性刺激导致NF-κB、PXR蛋白表达增加，PDTC抑制NF-κB活化减缓CYP450酶系下调，LPS抑制PXR转录抑制CYP3A4转录，地塞米松诱导PXR转录增加CYP3A4转录。CYP450翻译后修饰对CYP450活力产生重要的影响，磷酸化降低CYP1A2、CYP2E1、CYP3A4代谢活力；硝基化降低CYP2E1、CYP3A4活力；泛素化抑制CYP2E1、CYP3A4的代谢活力。本研究具有重要的科学意义及其临床价值。从肝脏药物代谢酶系的调控角度研究免疫性肝损伤发病机制，为肝病的药物治疗提供了新的靶点和治疗策略；揭示免疫损伤性肝炎时CYP450酶系转录调节的分子机制；揭示CYP450酶系的翻译后修饰机制。