RETN and cholestasis: Consistently, nine genes in the fatty acid metabolism, phospholipidosis and steatosis pathways including Acot2, Ugt2a1, Cd36 and Retn were upregulated in the cirrhotic liver post SPION injection accompanied with elevated Tgfb1 and sodium bile acid cotransporter (Slc10a1) of the cholestasis pathway28.