APP and Alzheimer disease: Research has underscored the role of cholesterol in lipid rafts in bringing APP and BACE1 closer, promoting rapid endocytosis, with the activities of BACE1 and γ-secretase also being influenced by cholesterol levels, indicating the significant impact of cholesterol metabolism on AD development (Allen et al., 2007; Nickels et al., 2019; Fabelo et al., 2014).