基于PPARα信号通路调控的水飞蓟宾逆转饮食联合药物诱导的肝损伤的作用机制研究

The high incidence of Non-alcoholic fatty liver disease and the symptoms are hidden, while drug abuse prone to cause drug-induced liver injury, the inherent susceptibility and over-consumption of drugs increases the risk of liver damage in the patients with fatty liver. Current research on the hepatoprotection mechanism of silibinin still restricted in diet, drugs or viruses and other single factor induced liver damage. Our study based on preliminary studies results, first in the animal and cell models of acute/chronic liver injury which induced by high-fat diet and drug, to clarify the contribution of the drug and high fat diet on the liver pathology process, and the reversing effect of Silibinin in hepatic lipid metabolism disorder, inflammatory response and its impact in hepatic drug metabolizing enzyme (CYP450 and UGTs). Secondary, study the regulation effect of silibinin on the quality key genes in PPARα signal pathway involved in lipid metabolism and apoptosis (SREBP-1c, FAS, ACOX1, Bcl-2, Fas, etc.) by animal, cellular and molecular level in-depth study, and combined the inflammatory cytokines and biochemical indicators to reveal the regulatory mechanism of silibinin reversal liver injury induced by drug combination diet. Our research results aim to compensate for the current neglect of multi-factor-induced liver injury and provide scientific basis for the prevention and treatment of such liver disease and the rational use of hepatoprotection drugs.

非酒精性脂肪肝病高发且症状隐蔽，药物滥用易致药物性肝损伤，脂肪肝患者的内在易感性与药物过度消费共同增加了肝损伤风险。当前国内外学者对水飞蓟宾的保肝机制研究多局限于饮食、药物或病毒等单因素所诱导的肝损伤。本课题拟在前期研究基础上，首先在高脂饮食联合药物诱导的急/慢性肝损伤动物和细胞模型中，阐明药物与高脂饮食对肝脏病理进程的贡献度，并明确保肝药水飞蓟宾对肝脂质代谢紊乱、炎症反应的逆转效果及其长期用药对肝药酶（CYP450和UGTs）的影响；其次从整体、细胞、分子水平深入研究水飞蓟宾对PPARα信号通路中涉及脂质代谢和细胞凋亡的关键基因（SREBP-1c，FAS，ACOX1，Bcl-2，Fas等）的调控，并结合炎症因子和生化指标，揭示水飞蓟宾逆转药物联合饮食诱导的肝损伤的调控机制。本课题旨为弥补当前对多因素诱导肝损伤认识的欠缺，并为同类肝脏疾病的防治研究及保肝药的临床合理应用提供科学依据。

非酒精性脂肪肝病高发且症状隐蔽，药物滥用易致药物性肝损伤，nafld患者的内在易感性与药物共同增加了肝损伤风险。本课题基于高脂联合药物诱导的的复合型肝损伤动物/细胞模型，深入研究水飞蓟宾逆转肝损伤的作用机制。本项目取得的研究成果如下：1) 在脂肪酸联合药物诱导的慢性肝损伤中，脂肪酸引起的脂质代谢紊乱、氧化应激为肝细胞损伤的主要因素；2）在脂肪酸联合药物诱导的急性肝损伤中，药物（如，四氯化碳、对乙酰氨基酚）导致的炎症反应及细胞凋亡为肝细胞损伤的主要因素。3）水飞蓟宾有效逆转慢性肝损伤中的脂质代谢紊乱和急性肝损伤中的炎症反应、细胞凋亡。4）依次从动物、细胞和分子水平阐明水飞蓟宾经由PPARα 对其下游靶标中的肝药酶 (CYP2E1、UGT1A6等）、脂质代谢相关蛋白（FASN、ACC、SCD、L-FABP等）和细胞凋亡（BCL2、FAS、CASP8）进行调控。水飞蓟宾上调UGTs的表达和活性，提高机体代谢解毒能力；下调CYP2E1及相关的炎症因子水平，缓解肝细胞的氧化应激损伤；纠正脂质合成蛋白（（FASN、ACC、SCD）、脂质转运蛋白（L-FABP） 的表达紊乱，减轻肝细胞内脂质沉积；上调BCL2的表达，下调FAS、CASP8的表达，抑制肝细胞凋亡。5) 基于血清代谢组学进一步证实高脂联合药物导致的慢性肝损伤造成脂肪酸类、氨基酸类和甘油磷脂类代谢通路紊乱。本课题揭示了多因素致肝损伤中主要致病因素，水飞蓟宾用药期间对肝药酶的影响，为临床相关肝脏疾病的防治及联合用药提供了科学依据。