Costunolide represses hepatic fibrosis through WW domain-containing protein 2-mediated Notch3 degradation
Costunolide represses hepatic fibrosis through WW domain-containing protein 2-mediated Notch3 degradation
复制标题
木香内酯通过含 WW 结构域的蛋白 2 介导的 Notch3 降解抑制肝纤维化
DOI：
10.1111/bph.14873
复制
发表时间：
2019-12-23
影响因子：
7.3
通讯作者：
He, Hong-wei
中科院分区：
文献类型：
--
作者：
Ge, Mao-xu;Liu, Hong-tao;He, Hong-wei
背景与目的本研究探讨了一种天然倍半萜类化合物木香酮（COS）的抗肝纤维化活性及其可能的作用机制。实验方法采用大鼠胆管结扎模型和小鼠四氯化碳（CCl_4）模型，研究COS的体内抗肝纤维化作用。小鼠原代肝星状细胞（pHSC）和人HSC系LX-2也用作体外肝纤维化模型。采用蛋白质印迹和/或实时PCR检测神经原性位点Notch同源蛋白3（Notch 3）-多毛/分裂增强子1（HES 1）通路中纤维化基因和信号蛋白的表达。使用免疫荧光和免疫共沉淀分析Notch 3降解。关键结果在动物中，COS给药减弱了肝脏组织病理学损伤和胶原积累，并减少了纤维化基因的表达。COS时间和剂量依赖性地抑制LX-2细胞和小鼠pHSC中纤维化标志物的水平。机制研究表明COS使Notch 3不稳定，随后抑制Notch 3-HES 1通路，从而抑制HSC活化。此外，COS阻断了含WW结构域的蛋白2（WWP 2）/蛋白磷酸酶1G（PPM 1G）的相互作用，并增强了WWP 2对Notch 3降解的影响。结论COS通过破坏WWP 2/PPM 1G复合物，促进Notch 3降解，抑制Notch 3/HES 1通路，在体内外均发挥抗肝纤维化作用。这表明COS可能是治疗肝纤维化的潜在治疗候选物。
Background and Purpose This study investigates the antifibrotic activities and potential mechanisms of costunolide (COS), a natural sesquiterpene compound. Experimental Approach Rats subjected to bile duct ligation and mice challenged with CCl4 were used to study the antifibrotic effects of COS in vivo. Mouse primary hepatic stellate cells (pHSCs) and human HSC line LX-2 also served as an in vitro liver fibrosis models. The expression of fibrogenic genes and signaling proteins in the neurogenic locus notch homologue protein 3 (Notch3)-hairy/enhancer of split-1 (HES1) pathway was examined using western blot and/or real-time PCR. Notch3 degradation was analysed using immunofluorescence and coimmunoprecipitation. Key Results In animals, COS administration attenuated hepatic histopathological injury and collagen accumulation and reduced the expression of fibrogenic genes. COS time- and dose-dependently suppressed the levels of fibrotic markers in LX-2 cells and mouse pHSCs. Mechanistic studies showed COS destabilized Notch3 and subsequently inhibited the Notch3-HES1 pathway, thus inhibiting HSC activation. Furthermore, COS blocked the WW domain-containing protein 2 (WWP2)/protein phosphatase 1G (PPM1G) interaction and enhanced the effect of WWP2 on Notch3 degradation. Conclusions and Implications COS exerted potent antifibrotic effects in vitro and in vivo by disrupting the WWP2/PPM1G complex, promoting Notch3 degradation and inhibiting the Notch3/HES1 pathway. This indicates that COS may be a potential therapeutic candidate for the treatment of liver fibrosis.