Identification of BA-activated G-protein-coupled receptors (GPCRs), Takeda GPCR 5 (TGR5, also known as GPBAR1) and sphingosine-1 phosphate receptor 2 (S1PR2), has made a significant advance by linking BAs with various metabolic diseases, including NAFLD [17,18,19]. This evidence concerns the gene GPBAR1 and metabolic disease.