INS and diabetes mellitus: Obeticholic acid (OCA, 6α-ethyl-chenodeoxycholic acid) is a semi-synthetic derivative of the primary human bile acid chenodeoxycholic acid, the natural agonist of the farnesoid X receptor that in a 6-week clinical trial was well tolerated, increased insulin sensitivity and reduced markers of liver inflammation and fibrosis in patients with type 2 diabetes mellitus and non-alcoholic fatty liver disease [131].