Fig. 5
From: Gut liver brain axis in diseases: the implications for therapeutic interventions
BAs biosynthesis, transport, and FXR-mediated BAs signaling in the gut-liver axis. BAs are synthesized in hepatocytes via CYPs-mediated oxidation of cholesterol to form CA and CDCA, which conjugate taurine, or glycine to form conjugated BAs and are secreted from the liver to the gallbladder and then into the intestine. Subsequently, gut microbes convert the primary BAs into secondary BAs. During gut dysbiosis, the expression of intestinal FXR is downregulated, leads to the increase of BAs synthesis and BAs influx, and the decrease of BAs efflux, and thus promote the progress of liver diseases. FXR also controls BAs detoxification and inflammation formation. Created with BioRender.com
