OBJECTIVE: This study was to investigate the molecular mechanism underlying the regulatory effect of Pae on hepatic stellate cells (HSCs) activation in liver fibrosis, with a specific focus on the role of Pae in modulating histone methylation modifications.
METHODS: The therapeutic effect of Pae was evaluated by establishing in vivo and in vitro models of carbon tetrachloride (CCl4)-induced mice and transforming growth factor β1 (TGF-β1)-induced LX-2 cells, respectively. Molecular docking, surface plasmon resonance (SPR), chromatin immunoprecipitation-quantitative real time PCR (ChIP-qPCR) and other molecular biological methods were used to clarify the molecular mechanism of Pae regulating HSCs activation.
RESULTS: Our study found that Pae inhibited HSCs activation and histone trimethylation modification in liver of CCl4-induced mice and LX-2 cells. We demonstrated that the inhibitory effect of Pae on the activation of HSCs was dependent on peroxisome proliferator-activated receptor γ (PPARγ) expression and enhancer of zeste homolog 2 (EZH2). Mechanistically, Pae directly binded to EZH2 to effectively suppress its enzymatic activity. This attenuation leaded to the suppression of histone H3K27 trimethylation in the PPARγ promoter region, which induced upregulation of PPARγ expression.
CONCLUSIONS: This investigative not only sheds new light on the precise targets that underlie the remission of hepatic fibrogenesis induced by Pae but also emphasizes the critical significance of EZH2-mediated H3K27 trimethylation in driving the pathogenesis of liver fibrosis.
目的:本研究旨在探讨Pae对肝纤维化中肝星状细胞(HSCs)活化的调控作用的分子机制。特别关注Pae在调节组蛋白甲基化修饰中的作用。
方法:通过建立四氯化碳(CCl4)诱导的小鼠体内和体外模型和转化生长因子β1(TGF-β1)诱导的LX-2细胞,评价Pae的治疗效果。分别。分子对接,表面等离子体共振(SPR),采用染色质免疫沉淀-实时定量PCR(ChIP-qPCR)等分子生物学方法阐明Pae调控HSCs活化的分子机制。
结果:我们的研究发现Pae抑制CCl4诱导的小鼠和LX-2细胞肝脏中的HSCs活化和组蛋白三甲基化修饰。我们证明了Pae对HSC活化的抑制作用取决于过氧化物酶体增殖物激活受体γ(PPARγ)的表达和zeste同源物2(EZH2)的增强子。机械上,Pae直接与EZH2结合以有效抑制其酶活性。这种衰减导致PPARγ启动子区组蛋白H3K27三甲基化的抑制,诱导PPARγ表达上调。
结论:这项研究不仅揭示了Pae诱导的肝纤维化缓解的精确目标,而且强调了EZH2介导的H3K27三甲基化在驱动肝纤维化发病机制中的重要意义。