非酒精性脂肪肝病理状态下的药物相互作用及相关机制研究

Liver disease threatened people's life all over the world because of the high fat and high fructose diet which might induce disorders of glucose and lipid metabolism, in accordance with high incidence of non-alcoholic fatty liver diseases (NAFLD). During non-alcoholic fatty liver disease, variations of pathomechanism and drug metabolism enzymes always influence the disposition of drugs in vivo. Since NAFLD are always companied by hyperlipemia, diabetes, or hypertension and so on, medication of NAFLD patients turns out to be complicated. The pharmacokinetic behaviors and drug/drug interactions (DDI) of these conventional drugs are probably different in NAFLD patients compared with healthy people. However, there was little reference pay attention to the influence of fatty liver to medication's pharmacokinetics, let alone the drug/drug interaction under fatty liver condition. ..Based on NAFLD model, this study choose conventional clinical used hepatoprotective agents, drugs of hyperlipemia and hypertension as probes to illustrate the differences of their pharmacokinetics and drug/drug interactions between pathological and healthy status, and further clarify the variation of drug metabolism enzymes in livers by PCR and Western Blot and the variation of endogenous molecules by metabonomics technology. Also, hepatocyte will be exposed to methionine-choline deficient (MCD) culture medium or high fat culture medium to induce cell injury and relative mechanisms of the regulation on drug metabolism enzymes under hepatocyte injury status will be taken out. Finally, the correlation between endogenous regulation and drug metabolism is to be interpreted. Through the pharmacokinetic study of conventional clinical medication, the change law of the dispositions of drugs and drug/drug interactions under liver disease will be clear which might help to supply new ideas for clinical therapeutic guidelines...This study is aimed to inspect and verify the scientific hypothesis that during non-alcoholic fatty liver disease the pharmacokinetics and drug/drug interactions of relative medication drugs will change which can be regulated by hepatoprotective agents. The extents of variations are probably associated with the extents of hepatic phathology/variation of drug metabolism enzymes/variation of endogenous molecules, which will provide theoretical foundation for dosage regiment and reasonable medication clinically.

非酒精性脂肪肝病理状态下，各项病理机制及药物代谢酶的改变，往往会影响药物在体内的处置过程；而脂肪肝常常伴随有高脂血症、糖尿病、高血压等诸多疾病的发生，使得病人的治疗相对复杂，因此，肝脏的不同病理程度和状态往往会影响相关治疗药物在体内的动力学过程，且须充分考虑病理状态下的药物/药物之间的相互作用（DDI）。本项目以非酒精性脂肪肝为基本病理模型，以临床常用的保肝药、高脂血症、高血压的治疗药物为探针，研究他们分别在病理状态和正常状态下的药物/药物相互作用，并通过对药物代谢酶和代谢组学的研究，验证科学假说：非酒精性脂肪肝病理状态会引起相关药物的药代动力学行为的改变和药物/药物相互作用的改变，这种改变可能受到保肝药治疗的调控，且变化程度和规律与肝损程度/药物代谢酶改变/内源性关键分子改变程度相关。通过建立药物的药代动力学行为的改变与病理程度/治疗效果之间的关联，为临床剂量调整和合理用药提供理论依据。

本项目的研究背景立足于当前高脂高糖的饮食习惯下，代谢综合症发病率愈来愈高，以高血糖、高血脂、高血压为代表的三高严重影响人类健康，意味着同时服用多种药物的概率增加。本项目以高脂（高糖）饮食造成非酒精性脂肪肝模型，研究肝脏脂肪变性病理状态下药物代谢酶的改变，以及相应的药物相互作用，并从脂质代谢紊乱的角度阐释内源性物质代谢与外源性药物代谢直接的关联。. 主要研究内容：（1）非酒精性脂肪肝大鼠模型下药物相互作用研究。非酒精性脂肪肝模型大鼠体内洛伐他汀的血浆暴露显著升高，AUC升高到正常对照组的1.53倍，半衰期延长到正常对照组的2.54倍，而姜黄素治疗使AUC和t1/2都有明显降低，这可能跟姜黄素使得模型大鼠肝脏CYP3A2表达量明显增加，向正常对照组恢复有关。我们推测姜黄素调节肝脏CYP3A2表达的作用与其肝保护作用密切相关，且CYP3A2水平的改变是造成洛伐他汀药代动力学行为改变的重要原因。（2）姜黄素对非酒精性脂肪肝小鼠脂质代谢途径及代谢酶的调控作用。姜黄素作用于Nrf2/LXR通路，逆转模型中下调的Nrf2水平，促进FXR脱乙酰化，从而诱导SHP的表达，抑制LXRα依赖的SERBP-1c的基因转录，达到抑制LXR介导的脂肪合成的目的。同时，LXR也直接参与CYP7A1和间接参与CYP3A的表达调控，姜黄素能明显上调模型中两者的表达，这提示姜黄素有协同调节脂质代谢紊乱中胆固醇的代谢CYP7A1和主要的药物代谢酶亚型CYP3A的作用，该作用很可能与途径有关。（3）姜黄素抑制脂肪组织脂解，减少肝脏脂质摄取和胰岛素抵抗。姜黄素能有效抑制棕榈酸或高脂饮食引起的脂肪组织内质网应激，降低白p-IRE1α和p-eIF2α的蛋白表达水平，通过抑制PKA/HSL脂解通路抑制脂肪组织发生脂解，减少FFA和甘油的释放，进而减少脂解产物DAG和TAG转移至肝脏，减少肝脏对DAG和TAG的摄取，抑制PKCε活化，减弱胰岛素导致的Akt磷酸化，从而有效防止肝细胞的胰岛素抵抗，抑制糖异生。. 科学意义：（1）基于代谢综合症多症并发多药并用的特殊性，从脂肪肝病模型出发，研究相关药物的相互作用，提示临床用药时需全面考虑，合理用药；（2）为内源性物质的代谢调控和外源性物质的代谢调控寻找关联点；（3）为姜黄素抑制肝脏胰岛素抵抗提供了新的研究思路。