A signaling molecule binds to the G-protein-coupled bile acid receptor 1 (GPBAR1 or TGR5), which regulates hepatic steatosis and the inflammatory response, and activates the expression of the FXR; this then controls the balance of energy metabolism, controls hepatic steatosis and the inflammatory response, and influences the composition of the intestinal tract. This evidence concerns the gene GPBAR1 and fatty liver disease.