BCL2 and Alzheimer disease: Studies have shown that cell death in AD is related to the changes in the expression of anti-apoptotic proteins (Bcl-2, Bcl-xL), which play an anti-apoptotic role by stabilizing the permeability of mitochondrial membrane and preventing the release of mitochondrial cytochrome C. Interestingly, the Pl3K/AKT signaling pathway can regulate the expression of mitochondrial membrane permeability protein Bcl-2, Bax and other proteins (Zeng et al., 2011).