VDR and metabolic dysfunction-associated steatotic liver disease: On top of that, hepatocyte VDR levels are induced by several conditions and stimuli: in human HepG2 cells, VDR expression is upregulated by free fatty acids, insulin, lithocholic acid (LCA), and VitD [4,7,8], and in human and mouse livers (e.g., apoE-/- mice on high-fat diet (HFD) or mice on methionine-choline deficient diet) VDR is significantly induced in the settings of non-alcoholic fatty liver disease (NAFLD) [9].