Sodium acetate attenuates hepatic fibrosis by modulating EPHB2-mediated signaling in hepatic stellate cells

Hepatic fibrosis (HF), characterized by excessive extracellular matrix (ECM) deposition, is an essential pathological process in chronic liver diseases, with limited therapeutic options. Short-chain fatty acids (SCFAs), produced by the gut microbiota, have demonstrated the ability to regulate inflammation and fibrotic processes. This study assessed the protective roles of SCFAs, including sodium acetate (NaA), sodium propionate (NaP), and sodium butyrate (NaB), against CCl₄-induced hepatic fibrosis in mice. Administration of SCFAs, particularly NaA and NaB, significantly ameliorated CCl₄-induced liver dysfunction by reducing serum ALT and AST levels, improving histopathological architecture, and attenuating lipid deposition and inflammation through inhibition of NF-κB signaling. NaA led to a substantial reduction in collagen deposition, accompanied by downregulation of Col1a1, Acta2, and Tgf-β1 gene expression. In vitro, NaA also inhibited activation and proliferation of TGF-β1-activated LX2 hepatic stellate cells (HSCs), by downregulating ECM markers (FN1, COL1A1) and modulating the mRNA levels of MMP-9 and TIMP-1. Data-independent acquisition (DIA) -based proteomic analysis identified 25 differentially expressed proteins (DEPs) reversed by NaA treatment, with ephrin receptor B2 (EPHB2) identified as a key target. Combined treatment with NaA and the EPHB2 inhibitor AWL-II-49-7 did not further inhibit LX2 cells activation, but resulted in a greater suppression of EPHB2 protein expression, supporting EPHB2 as a key mediator of the antifibrotic effects of NaA. These findings highlight the anti-fibrotic potential of SCFAs, particularly NaA, through EPHB2-mediated pathways, providing a novel potential therapeutic strategy for HF.