新型HATs抑制剂EQ-530调控VDAC1位点K224乙酰化修饰抗肝纤维化的机制研究

Abnormal protein acetylation modifications mediated by histone acetyltransferases (HATs) are closely related to liver fibrosis, therefore, HATs may be new important targets for prevention and control of liver fibrosis. By screening a library of 4406 natural compounds, in our previous studies, we found a new HATs inhibitor EQ-530, which can induce HSCs apoptosis in vitro and its effectiveness in improving liver fibrosis was preliminary confirmed in animal models. Although previous studies identified the differentially acetylated proteins, especially VDAC1(K224) and ATF2(K356), before and after the intervention of EQ-530, there are many scientific questions regarding the mechanisms raised: firstly, what are the effects of EQ-530 by regulating acetylation modification of ket proteins on the phenotypes of HSCs? secondly, what is the mechanism suggested by the interactive networks of the differentially modified proteins? thirdly, whether the observed differential acetylation sites observed in HSCs can be regulated by EQ-530 in vivo? We propose to further study the regulatory mechanisms on cells, animal models and clinical samples, through biological information analysis, cell transfection, Co-IP, immunofluorescence and immune electron microscopy, etc., to solve the scientific questions. Our study may also contribute to new molecular targets for the treatment of liver fibrosis and the development of leading compounds.

组蛋白乙酰化酶(HATs)介导的蛋白乙酰化修饰异常与肝纤维化密切相关，HATs可能是肝纤维化防治的新靶点。前期研究筛选4406种天然小分子化合物，发现一种新HATs抑制剂EQ-530，初步证实它能诱导肝星状细胞HSCs凋亡、动物模型上有效改善肝纤维化；双向电泳及蛋白质印迹鉴定到EQ-530干预前后，发生乙酰化修饰的差异蛋白和修饰位点是VDAC1(K224)和ATF2(K356)。而详细机制尚待明确：EQ-530调控关键蛋白乙酰化修饰对HSCs细胞表型和生物学活性的影响？差异蛋白间的相互作用及机制？EQ-530在体内是否调控差异蛋白的乙酰化修饰？为此，我们拟在细胞、动物模型及临床样本上深入研究，通过生物信息学分析、转染野生型和突变型质粒验证，Co-IP、免疫荧光等方法解答以上科学问题，有助于阐明蛋白乙酰化修饰在肝纤维化进程中的调控机制，获得肝纤维化防治新靶点，为开发先导化合物提供实验依据。

肝纤维化是严重的全球性健康难题，目前缺乏有效的治疗方法。组蛋白乙酰化酶(HATs)介导的蛋白乙酰化修饰异常与肝纤维化密切相关，HATs可能是肝纤维化防治的新靶点。前期研究筛选4406种天然小分子化合物，发现一种新HATs抑制剂EQ-530，也即是冬凌草甲素（Oridonin），证实它能诱导肝星状细胞HSCs凋亡、动物模型上有效改善肝纤维化；双向电泳及蛋白质印迹鉴定到Oridonin干预前后，发生乙酰化修饰的差异蛋白和修饰位点。通过系列研究揭示HATS抑制剂Oridonin在肝纤维化及肝衰竭进程中蛋白乙酰化修饰异常所起的关键作用，为肝纤维化及肝衰竭临床治疗提供新的分子靶点; 为开发抗肝纤维化化合物提供理论实验依据和新思路。.前期筛选的抗肝纤维化小分子化合物由于存在水溶性、靶向性不佳的缺点，限制了其运用前景，怎样才能发挥药物体内抗肝纤维化效果，促进临床转化？课题组通过将其装载到exosomes中克服其溶解性和靶向性的难题。此外，也利于发挥小分子化合物和exosomes协同抗肝纤维化的作用。同时能提升对exosomes作为一种普适性药物装载平台的认识。后续课题组拟采用蛋白质组学和转录组学（RNA-seq）多组学联合分析、并结合分子及细胞生物学层面的功能验证实验明确exosomes载药治疗体系改善肝纤维化的分子机制，并利用患者样本评价效应分子在肝纤维化临床运用的可能性。