Sirt1/HMGB1在非酒精性脂肪性肝病发生发展中的关键作用及丹参酚酸B的调控机制研究

It has been proposed that excessive inflammation promotes nonalcoholic steatohepatitis to liver fibrosis, cirrhosis, the end stages and even hepatocarcinoma, is an important contributing factor in the progression of nonalcoholic fatty liver disease (NAFLD). HMGB1 may play a pivotal role in the inflammatory response in NAFLD which may be modulated by Sirt1, however it still lack direct evidences. In our previous study, it was firstly found that salvianolic acid B (Sal B) has the therapeutic effect on NASH and the mechanism may be related to activate Sirt1and inhibit HMGB1 which relieved the inflammation. Therefore, on the basis of preliminary data, this research project is performed to prove the key role of Sirt1/HMGB1 in NAFLD progression with NAFLD rats induced by high-fat fed and LO2, LX-2 and Kupffer cells induced by free fatty acid. We will apply the various techniques such as blocking agents, siRNA, over expression, co-immuno-precipitation to investigate the molecular mechanism of Sal B against NAFLD through this pathway. This study will provide some new ideas and targets for prevention and treatment NAFLD, meanwhile it will accumulate the experimental data for Sal B against NAFLD.

过度的炎症反应推动着非酒精性脂肪性肝病（NAFLD）的发生发展，促使非酒精性脂肪性肝炎向肝纤维化、肝硬化和终末肝病甚至肝癌转化。HMGB1在NAFLD炎症中发挥重要作用，该作用可能受Sirt1调节，但尚无直接证据。我们前期研究首次发现丹参酚酸B（Sal B）有抗NAFLD作用，结果表明Sal B上调Sirt1表达，抑制肝损伤时HMGB1升高，缓解炎症。因此，本项目拟在此基础上：通过高脂诱导大鼠NAFLD模型和脂肪酸诱导LO2、LX-2及大鼠原代Kupffer细胞脂质损伤模型，应用阻断剂、siRNA、过表达、免疫共沉淀等技术，阐明Sirt1/HMGB1在NAFLD发生发展中发挥关键作用；明确Sal B通过激活Sirt1，调节HMGB1活性，发挥抗NAFLD作用的分子机制。此研究将为NAFLD的防治提供新思路和新靶点，为Sal B用于防治NAFLD提供实验依据，具有重要的科学与社会意义。

非酒精性脂肪性肝病（NAFLD）在发病率极高，但是NAFLD发生发展的详细机制目前仍然知之甚少，因此尚缺乏有效的治疗手段。过度的炎症反应推动着非酒精性脂肪性肝病（NAFLD）的发生发展，促使非酒精性脂肪性肝炎向肝纤维化、肝硬化和终末肝病甚至肝癌转化。HMGB1在NAFL D炎症中发挥重要作用，该作用可能受Sirt1调节，但尚无直接证据。我们前期研究首次发现丹参酚酸B有抗NAFLD作用，进一步研究发现丹酚酸B上调Sirt1表达，抑制肝损伤时HMGB1升高，缓解炎症。本项目在此基础上：通过高脂诱导大鼠和小鼠NAFLD模型和脂肪酸诱导人肝癌细胞HepG2和小鼠正常肝细胞AML12脂质损伤模型，应用阻断剂、siRNA、过表达、免疫共沉淀等技术，阐明Sirt1/HMGB1在NAFLD发生发展中发挥关键作用；明确丹酚酸B通过激活Sirt1，抑制HMGB1的核质易位与释放有关。进一步发现，丹酚酸B对高脂饮食诱导的小鼠以及PA诱导小鼠正常细胞中对脂质损伤也就有对抗作用。进一步研究发现，丹酚酸B可通过miR-212-3p调节SIRT1通路，且对肝细胞线粒体功能具有明显保护作用。此研究将为NAFLD的防治提供新思路和新靶点，为丹酚酸B用于防治NAFLD提供实验依据，具有重要的科学与社会意义。.该研究成果获得大连市科技进步一等奖1项，发表SCI论文4篇，培养硕士研究生3名，参加国内外学术交流各1次。.本研究在国内外首次报道丹酚酸B对高脂性脂肪性肝炎的保护作用，其作用机制与SIRT1通路密切相关。同时该成果极大拓展了传统中药丹参制剂的临床应用范围，特别是将原来仅用于心血管系统的药物用于保肝治疗。