Plasma levels of amyloid beta-protein 42 are increased in women with mild cognitive impairment.
BACKGROUND
Accumulation in the brain of small aggregates of amyloid beta-protein 42 (Abeta42) is the major pathogenic event of Alzheimer disease (AD). In familial early-onset AD this event is likely the result of Abeta42 overproduction; in the most common sporadic late-onset form of the disease the mechanisms of Abeta42 accumulation are unknown.


METHODS
To address this issue the authors analyzed plasma levels of Abeta42 in 88 elderly patients with amnestic mild cognitive impairment (MCI), chosen as paradigm of preclinical sporadic AD.


RESULTS
The authors found a significant increase of Abeta42 plasma levels in women with MCI, in comparison to the affected men and 72 cognitively normal age-matched subjects. The levels were independent of variables in education, apolipoprotein E genotype, cholesterol, and creatinine plasma concentrations, as well as hemoglobin content.


CONCLUSIONS
The elevation of Abeta42 plasma levels in women with MCI may represent a biologic explanation for the sex-dependent increased incidence of late-onset AD in women identified by epidemiologic studies.
Assini
A
A
Department of Neurosciences, University of Genoa, Genoa, Italy.
Cammarata
S
S
Vitali
A
A
Colucci
M
M
Giliberto
L
L
Borghi
R
R
Inglese
M L
ML
Volpe
S
S
Ratto
S
S
Dagna-Bricarelli
F
F
Baldo
C
C
Argusti
A
A
Odetti
P
P
Piccini
A
A
Tabaton
M
M
D017668:Age of Onset; D000368:Aged; D000544:Alzheimer Disease / Q000097:blood / Q000453:epidemiology; D016229:Amyloid beta-Peptides / Q000097:blood*; D001057:Apolipoproteins E / Q000235:genetics; D015415:Biomarkers; D002784:Cholesterol / Q000097:blood; D003072:Cognition Disorders / Q000097:blood* / Q000453:epidemiology; D003401:Creatine / Q000097:blood; D004522:Educational Status; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D015994:Incidence; D008297:Male; D008569:Memory Disorders / Q000097:blood / Q000453:epidemiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000097:blood*; D017678:Sex Distribution
D016229:Amyloid beta-Peptides; D001057:Apolipoproteins E; D015415:Biomarkers; D006454:Hemoglobins; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42); D002784:Cholesterol; D003401:Creatine