NR1H4 and type 2 diabetes mellitus: In NAFLD patients with T2DM, obeticholic acid (OCA, an FXR agonist) activates FXR to mediate an increase in FGF19, resulting in weight loss and improved insulin sensitivity, accompanied by decreased endogenous BA production and 7a-hydroxy-4-cholesten-3-one (C4, a biomarker for BA synthesis) levels (151).