Laboratory Animal Resources Center, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, No. 100 Minjiang Road, Quzhou 324000, China; Panvascular Diseases Research Center, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou 324000, China.
College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, No. 548 Binwen Road, Hangzhou 310053, China.
Phytomedicine. 2024 Jun;128:155477. doi: 10.1016/j.phymed.2024.155477. Epub 2024 Feb 24.
The alleviating effect of paeoniflorin (Pae) on liver fibrosis has been established; however, the molecular mechanism and specific target(s) underlying this effect remain elusive.
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.
The therapeutic effect of Pae was evaluated by establishing in vivo and in vitro models of carbon tetrachloride (CCl)-induced mice and transforming growth factor β (TGF-β)-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.
Our study found that Pae inhibited HSCs activation and histone trimethylation modification in liver of CCl-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.
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.
白芍总苷（Pae）对肝纤维化的缓解作用已得到证实；然而，其作用的分子机制和特定靶点仍不清楚。
本研究旨在探讨白芍总苷调节肝纤维化中肝星状细胞（HSCs）活化的分子机制，特别关注白芍总苷在调节组蛋白甲基化修饰中的作用。
分别通过建立四氯化碳（CCl）诱导的小鼠和转化生长因子β（TGF-β）诱导的 LX-2 细胞体内和体外模型来评估白芍总苷的治疗效果。采用分子对接、表面等离子体共振（SPR）、染色质免疫沉淀-定量实时 PCR（ChIP-qPCR）等分子生物学方法，阐明白芍总苷调节 HSCs 活化的分子机制。
我们的研究发现，白芍总苷抑制 CCl 诱导的小鼠和 LX-2 细胞肝内 HSCs 活化和组蛋白三甲基化修饰。研究表明，白芍总苷抑制 HSCs 活化的作用依赖于过氧化物酶体增殖物激活受体γ（PPARγ）表达和增强子的锌指蛋白 2（EZH2）。机制上，白芍总苷直接与 EZH2 结合，有效地抑制其酶活性。这种抑制作用导致 PPARγ启动子区域的组蛋白 H3K27 三甲基化减少，从而诱导 PPARγ表达上调。
本研究不仅为白芍总苷缓解肝纤维化的潜在靶点提供了新的见解，还强调了 EZH2 介导的 H3K27 三甲基化在驱动肝纤维化发病机制中的关键作用。
