APP and Alzheimer disease: Targeting BACE-1 or γ-secretase enzymes is identified as the most effective treatment method for AD because Aβ build-up leads to aberrant enzymatic cleavage of APP by β- and γ-secretase enzymes, resulting in the production of Aβ oligomers (Durairajan et al., 2008; Fujiwara et al., 2009).