ABSTRACT
Although the pathogenesis of AD is complex, there is compelling evidence that the neuritic dystrophy, neurofibrillary tangle formation, microglial reactivity, gliosis and other degenerative changes observed in the brains of AD patients are a result of the cerebral accumulation and deposition of amyloid β (Aβ) peptides.2,3 Aβ peptides are generated by proteolytic processing of the amyloid precursor protein (APP), a type I, single transmembrane glycoprotein, as a result of the action of β-and γ-secretase activities. Alternatively, APP can be cleaved by α-secretase, which precludes the formation of Aβ. The relative utilization of each processing route is controlled by numerous signal transduction pathways.4 Since cerebral accumulation and subsequent deposition of Aβ seem necessary for both disease initiation and its clinical progression, therapies that attenuate
these processes might delay onset and/or retard disease progression.
