Aβ42, Presenilins, and Alzheimer’s Disease

The significance of amyloid β protein, especially those ending at the 42nd residue (Aβ42), in the pathogenesis of familial Alzheimer’s disease (FAD) linked to the mutations of presenilins, was examined by transfection studies using cultured cells and immunohistochemical analysis of autopsied brains. The levels of Aβ42 secreted from cells transfected with mutant presenilins linked to FAD, as well as the Aβ42 burden in the cortices of patients with presenilin mutation were elevated. Thus, mutations in presenilin genes may enhance the production and deposition of Aβ42 in the brains, thereby leading to Alzheimer’s disease.