Gardenia jasminoides Ellis. Polysaccharides Alleviated Cholestatic Liver Injury by Increasing the Production of Butyric Acid and FXR Activation

positive areas in the liver, and inhibited liver inflammation in cholestatic mice. Butyric acid was the most notable intestinal bacterial metabolite following GPS intervention. NaB activated the transcriptional activity of FXR in vitro, upregulated hepatic FXR and its downstream efflux transporter expression, and ameliorated disordered BA homeostasis in CLI mice. NaB inhibited the toll-like receptor 4/nuclear factor (TLR4/NF-κB) pathway and reduced inflammation and CLI in mice. An FXR antagonist suppressed the effects. In conclusion, GPS increased butyric acid production, which can activate hepatic FXR, reverse BA homeostasis disorder, and inhibit the TLR4/NF-κB inflammatory pathway, exerting protective effects against CLI.