Revealing potential anti-fibrotic mechanism of Ganxianfang formula based on RNA sequence

Background: Ganxianfang (GXF) formula as a traditional Chinese medicine (TCM) is used for liver fibrosis in clinical practice while its mechanism is unclear. The aim of this study is to explore the molecular mechanism of GXF against CCl₄-induced liver fibrosis rats.

Methods: Detected the main compounds of GXF by UPLC-MS/MS. Evaluated the efficacy of GXF (1.58, 3.15, 4.73 g/kg/day) and Fuzheng Huayu (FZHY, positive control, 0.47 g/kg/day) through serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) levels and histopathological changes. Explored the underlying mechanisms by integrating our total liver RNA sequencing (RNA-seq) data with recent liver single-cell sequencing (scRNA-seq) studies. Verified potential pharmacodynamic substances of GXF by hepatic stellate cell (HSC)-T6 line.

Results: Main compounds were identified in GXF by UPLC-MS/MS, including baicalin, wogonoside and matrine etc. With GXF-high dose treatment, the elevation of ALT and AST induced by CCl₄ were significantly reduced, and the protective effect of GXF-high dose treatment was better than FZHY. Liver histopathological changes were alleviated by GXF-high dose treatment, the ISHAK scoring showed the incidence of liver cirrhosis (F5/F6) decreased from 76.5 to 55.6%. The results of liver hydroxyproline content were consistent with the histopathological changes. RNA-seq analysis revealed the differential genes (DEGs) were mainly enriched in ECM-receptor interaction and chemokine signaling pathway. GXF effectively inhibited collagen deposition and significantly downregulated CCL2 to inhibit the recruitment of macrophages in liver tissue. Integrating scRNA-seq data revealed that GXF effectively inhibited the expansion of scar-associated Trem2⁺CD9⁺ macrophages subpopulation and PDGFRα⁺PDGFRβ⁺ scar-producing myofibroblasts in the damaged liver, and remodeled the fibrotic niche via regulation of ligand-receptor interactions including TGFβ/EGFR, PDGFB/PDGFRα, and TNFSF12/TNFRSF12a signaling. In vitro experiments demonstrated that baicalin, matrine and hesperidin in GXF inhibited the activation of hepatic stellate cells.

Conclusions: This study clarified the potential anti-fibrotic effects and molecular mechanism of GXF in CCl₄-induced liver fibrosis rats, which deserves further promotion and application.