VLDLR在酒精性脂肪肝和肝损伤进展中的作用和机制研究

The morbidity and mortality of alcoholic liver disease (ALD) is comparative, and especially its morbidity in China elevates with time. But the etiology of this disease is elusive. Alcoholic fatty liver and liver injury occur in the early stage of ALD development, in which the course is reversible and the effective intervention is available. The application for the first time focuses on how alcohol consumption alters very low-density lipoprotein receptor (VLDLR) expression pattern (extrahepatic vs. hepatic) in whole body, thereby affecting triglyceride-rich lipoproteins (TRLs) metabolism, leading to fatty liver and liver injury. Firstly, knock out mice and TRLs clearence test are applied to furtherly determine the critical role of VLDLR in the pathogenesis of ALD, and then the preventive and therapeutic potential of VLDLR is validated. In in vitro investigation,VLDLR gene overexpresson, chromatin immunoprecipitation, luciferase activity assay, immunoblotting and real time PCR are applied to determine the mechanism for how VLDLR overexpression induces lipid deposition in hepatocyte and how VLDLR overexpression primes Kupffer cells to LPS stimulation. Ultimately, the underlying mechanisms of hepatic VLDLR overexpression are explored through hypomethylation and oxidative stress. The application aims to explore the etiology of alcoholic fatty liver and liver injury via VLDLR, and to validate its potential intervention for ALD.

酒精性肝病（ALD）发病率和死亡率较高，我国发病率持续呈上升趋势，但病因不清。酒精性脂肪肝和肝损伤处于发病早期，病程可逆，是实施干预的有效时机。本申请首次研究慢性酒精作用如何改变机体极低密度脂蛋白（VLDLR）表达模式（肝内和肝外），影响富含甘油三酯脂蛋白(TRLs)代谢，最终导致脂肪肝和肝损伤。首先应用基因敲除鼠结合TRLs清除实验进一步明确VLDLR在ALD病理生成中的关键作用，并验证VLDLR作为靶点防治ALD的潜力。 然后应用VLDLR 基因过表达、染色质免疫共沉淀、荧光素酶活性测定、免疫印迹和实时定量PCR等方法，明确肝细胞过表达VLDLR诱导脂肪积聚以及库伯细胞过表达VLDLR强化LPS炎症刺激敏感性的相关机制，最终从低甲基化和氧化应激两个角度探寻肝脏VLDLR过表达的相关机制。本申请从VLDLR角度探究酒精性脂肪肝和肝损伤的原因，并探索潜在的干预方式。

酒精性肝病（ALD）发病率和死亡率较高，我国发病率持续呈上升趋势，但病因不清。酒精性脂肪肝和肝损伤处于发病早期，病程可逆，是实施干预的有效时机。本申请首次研究慢性酒精作用通过抗氧化转录因子Nrf2诱导肝脏极低密度脂蛋白（VLDLR）表达增高，最终导致脂肪肝和肝损伤。首先应用基因敲除鼠明确VLDLR和Nrf2在ALD病理生成中的关键作用。然后应用VLDLR基因过表达、免疫印迹和实时定量PCR等方法，明确肝细胞过表达VLDLR和活化Nrf2诱导脂肪积聚和保护肝损伤的相关机制，最终从甲基化和聚腺苷二磷酸核苷化两个角度探寻肝脂肪沉积的相关机制。