Germacrone improves liver fibrosis by regulating the PI3K/AKT/mTOR signalling pathway

Abstract Liver fibrosis is a primary threat to public health, owing to limited therapeutic options. Germacrone (GM) has been shown to exert various curative effects against human diseases, including liver injury. The aim of this study was to investigate the pharmacological effects of GM in the pathophysiology of hepatic fibrosis and determine its potential mechanisms of action. A liver fibrosis rat model was established via carbon tetrachloride (CCl 4 ) treatment, and LX‐2 cells were stimulated with TGF‐β1. The effects of GM on liver fibrosis and its relationship with the phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signalling pathway were investigated. In the CCl 4 fibrosis‐induced rat model, GM improved histological damage, inhibited the activity of hepatic α‐smooth muscle actin and improved serum alanine aminotransferase and aspartate aminotransferase levels in a dose‐dependent manner. GM potently inhibited hepatic stellate cells (HSCs) growth and epithelial–mesenchymal transition (EMT) progression, as reflected by the altered expression of proliferative (Ki‐67, PCNA and cleaved caspase‐3) and EMT‐related (E‐cadherin and vimentin) proteins. In TGF‐β1‐stimulated LX‐2 cells, GM significantly inhibited the survival and activation of HSCs and induced cell apoptosis. GM also suppressed the migration ability and reversed the EMT process in HSCs. Following GM treatment, the phosphorylation of the PI3K, AKT and mTOR proteins was reduced in the liver of CCl 4 ‐treated rats and TGF‐β1‐stimulated LX‐2 cells, indicating that GM may attenuate hepatic fibrosis via the PI3K/AKT/mTOR signalling pathway. These outcomes highlight the anti‐fibrotic effects of GM and suggest that it is a potential therapeutic agent for the treatment of liver fibrosis.