Brain levels of sex steroid hormones in men and women during normal aging and in Alzheimer's disease.
We examined the relationships between normal aging, Alzheimer's disease (AD), and brain levels of sex steroid hormones in men and women. In postmortem brain tissue from neuropathologically normal, postmenopausal women, we found no age-related changes in brain levels of either androgens or estrogens. In comparing women with and without AD at different ages, brain levels of estrogens and androgens were lower in AD cases aged 80 years and older but not significantly different in the 60-79 year age range. In male brains, we observed that normal aging was associated with significant decreases in androgens but not estrogens. Further, in men aged 60-79 years, brain levels of testosterone but not estrogens were lower in cases with mild neuropathological changes as well as those with advanced AD neuropathology. In male cases over age 80, brain levels hormones did not significantly vary by neuropathological status. To begin investigating the relationships between hormone levels and indices of AD neuropathology, we measured brain levels of soluble β-amyloid (Aβ). In male cases with mild neuropathological changes, we found an inverse relationship between brain levels of testosterone and soluble Aβ. Collectively, these findings demonstrate sex-specific relationships between normal, age-related depletion of androgens and estrogens in men and women, which may be relevant to development of AD.
Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA.
Emily R
ER
Rosario
Lilly
L
Chang
Elizabeth H
EH
Head
Frank Z
FZ
Stanczyk
Christian J
CJ
Pike
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism* / Q000473:pathology; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000728:Androgens / Q000378:metabolism*; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D004967:Estrogens / Q000378:metabolism*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay
D016229:Amyloid beta-Peptides; D000728:Androgens; D004967:Estrogens