BDNF and Alzheimer disease: In an AlCl3-induced AD model, CDCA treatment could ameliorate neurotoxicity and cognitive deterioration via enhanced insulin signaling in rat hippocampus by decreasing the phosphorylation of insulin receptor substrate ser307 (PSER307-IRS1), activating cAMP response element-binding protein (CREB), and enhancing brain-derived neurotrophic factor (BDNF) [111].