title: Relative abundance of Alzheimer A beta amyloid peptide variants in Alzheimer disease and normal aging.
abstract: The Alzheimer A beta amyloid peptide (A beta) is the principal proteinaceous component of amyloid associated with Alzheimer disease (AD). We have determined the relative abundance of A beta structural variants present in amyloid from brains of 10 individuals with sporadic AD, 2 individuals with familial AD carrying specific mutations in the Alzheimer amyloid precursor protein gene, and 5 nondemented elderly controls. A procedure of isolation based on the extreme insolubility of A beta amyloid was used. The purified, nondigested A beta was analyzed by N-terminal sequencing and electrospray-ionization mass spectrometry. Three principal A beta variants were detected--A beta-(1-40), A beta-(1-42), and A beta-(11-42)--in all brains analyzed. The predominant variant in sporadic AD was A beta-(1-40), whereas the principal A beta variant in nondemented elderly controls was A beta-(1-42). The ratio A beta-(1-40)/A beta-(1-42) differed by 10-fold between brains from nondemented controls and those with sporadic AD.
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Näslund
authors.forename: A
authors.initials: A
authors.lastname: Schierhorn
authors.forename: U
authors.initials: U
authors.lastname: Hellman
authors.forename: L
authors.initials: L
authors.lastname: Lannfelt
authors.forename: A D
authors.initials: AD
authors.lastname: Roses
authors.forename: L O
authors.initials: LO
authors.lastname: Tjernberg
authors.forename: J
authors.initials: J
authors.lastname: Silberring
authors.forename: S E
authors.initials: SE
authors.lastname: Gandy
authors.forename: B
authors.initials: B
authors.lastname: Winblad
authors.forename: P
authors.initials: P
authors.lastname: Greengard
mesh_terms: D000368:Aged; D000375:Aging; D000544:Alzheimer Disease / Q000235:genetics*; D000595:Amino Acid Sequence; D016229:Amyloid beta-Peptides / Q000235:genetics*; D016564:Amyloid beta-Protein Precursor / Q000235:genetics; D002540:Cerebral Cortex / Q000737:chemistry; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009154:Mutation
chemical_list: D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor