Plasma amyloid β-peptide 1-42 and incipient Alzheimer's disease

Abstract

Mutations in the amyloid precursor protein and presenilin 1 and 2 genes result in elevated plasma levels of the amyloid β-peptide species terminating at amino acid residue 42 (Aβ1-42). In a longitudinal study of unrelated elderly individuals, those who subsequently developed Alzheimer's disease had higher plasma levels of Aβ1-42 at entry than did those who remained free of dementia. The results indicate that elevated plasma levels of the released Aβ peptide Aβ1-42 may be detected several years before the onset of symptoms, supporting that extracellular Aβ1-42 plays an important role in the pathogenesis of late-onset Alzheimer's disease.