title: Markers of cholesterol metabolism in the brain show stronger associations with cerebrovascular disease than Alzheimer's disease.
abstract: Cholesterol metabolism is believed to play a role in the development of Alzheimer's disease (AD). Oxysterol metabolites of cholesterol, 24S-hydroxycholesterol (24-OHC, a brain-derived oxysterol) and 27-hydroxycholesterol (27-OHC, a peripherally derived oxysterol) cross the blood brain barrier and have been associated with AD. We investigated whether oxysterols were associated with markers of cerebrovascular disease prior to the onset of cognitive impairment. Oxysterols were quantified in 105 participants (average age: 80 ± 4 years) from the Pittsburgh Cardiovascular Health Study Cognition Study who remained cognitively normal at blood draw in 2002, had MRI in 1992 and 1998, and annual cognitive assessment for incident AD and mild cognitive impairment made by consensus conference between 1998 and 2010. Higher plasma levels of 24-OHC were associated with age, gender, the presence of high grade white matter hyperintensities, and brain infarcts on prior MRI. Participants with higher plasma 24-OHC and a greater ratio of 24-OHC/27-OHC were also more likely to develop incident cognitive impairment over 8 years of follow-up. Higher levels of 24-OHC suggest increased cholesterol metabolism occurring in the brains of participants with cerebrovascular disease prior to the onset of cognitive impairment. Measurement of oxysterols may provide information about cholesterol metabolism and brain disease over the cognitive impairment process.
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, 130 N. Bellefield Street, Pittsburgh, PA 15213, USA. tmh57@pitt.edu
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Hughes
authors.forename: Lewis H
authors.initials: LH
authors.lastname: Kuller
authors.forename: Oscar L
authors.initials: OL
authors.lastname: Lopez
authors.forename: James T
authors.initials: JT
authors.lastname: Becker
authors.forename: Rhobert W
authors.initials: RW
authors.lastname: Evans
authors.forename: Kim
authors.initials: K
authors.lastname: Sutton-Tyrrell
authors.forename: Caterina
authors.initials: C
authors.lastname: Rosano
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism / Q000473:pathology*; D053327:Apolipoprotein E4; D001921:Brain / Q000378:metabolism / Q000473:pathology*; D002561:Cerebrovascular Disorders / Q000097:blood* / Q000473:pathology*; D003072:Cognition Disorders / Q000209:etiology / Q000378:metabolism; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006888:Hydroxycholesterols / Q000097:blood*; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies
chemical_list: D053327:Apolipoprotein E4; D006888:Hydroxycholesterols; C044563:24-hydroxycholesterol; C076996:27-hydroxycholesterol