MAPT and Alzheimer disease: Inhibition of CYP46A1 activity in the APP23 AD mouse model limits cholesterol export from the brain and increases levels of hyperphosphorylated Tau (pTau) (44), while overexpression of CYP46A1 (to induce export of brain cholesterol) in THY-Tau22 mice rescues Tau-mediated memory impairment (38).