Lysimachiae Herba Modulates FXR to Alleviate Cholestatic Liver Injury: Insights from Serum Pharmacochemistry and...

Cholestatic liver injury (CLI) is a complex condition for which current treatment options remain limited. Lysimachiae Herba (LH), a traditional Chinese medicine with hepatoprotective properties, has not yet been fully characterized in terms of its active constituents and underlying mechanisms in CLI. This study was designed to systematically determine the chemical composition of LH, characterize its absorbed constituents in vivo, and elucidate its therapeutic mechanisms against CLI. UPLC-Q-TOF-MS/MS was employed to analyze the chemical composition of LH and its absorbed components in rat serum. Key targets and signaling pathways were predicted using network pharmacology and molecular docking, followed by experimental validation in an ANIT-induced CLI mouse model and LCA-treated HepG₂ cells through biochemical assays, histological examination, transcriptomic analysis, qRT-PCR, Western blotting, and immunofluorescence analysis. A total of 129 compounds were tentatively identified in LH, among which 26 were detected in the bloodstream. Network analysis and molecular docking suggested that LH regulates bile acid homeostasis predominantly by the FXR signaling pathway. Both in vivo and in vitro experiments provided convergent evidence that LH modulates the FXR-related bile acid regulatory network, enhances bile acid efflux transporter expression, and alleviates CLI. In conclusion, this study systematically elucidates the chemical composition, absorbed constituents, and pharmacological mechanisms of LH in CLI, highlighting the involvement of FXR-related bile acid regulation as an important mechanism and providing a scientific basis for the potential development of LH for cholestatic liver injury.