title: Age-related increases in brain monoamine oxidase B in living healthy human subjects.
abstract: Several studies of human brain postmortem report that monoamine oxidase B (MAO B) increases with age and it has been proposed that this increase reflects age-associated increases in glial cells. We measured brain MAO B in a group of normal healthy human subjects (n = 21; age range 23-86; 9 females and 12 males; nonsmokers) using [11C]L-deprenyl-D2 and positron emission tomography. Brain glucose metabolism was also measured with 18FDG in 15 of the subjects. MAO B increased (p < 0.004) in all brain regions examined except the cingulate gyrus. In contrast, subjects showed the expected regional age-related decreases in blood flow and metabolism. In the 15 subjects in whom both MAO B and LCMRglu was measured, there was a trend (p < 0.03) toward an inverse association between brain glucose metabolism and MAO B activity in the frontal and parietal cortices. Although the age-related increase in brain MAO B in living subjects is consistent with postmortem reports, the degree of increase is generally lower.
authors.affiliation: Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Fowler
authors.forename: N D
authors.initials: ND
authors.lastname: Volkow
authors.forename: G J
authors.initials: GJ
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Logan
authors.forename: N
authors.initials: N
authors.lastname: Pappas
authors.forename: C
authors.initials: C
authors.lastname: Shea
authors.forename: R
authors.initials: R
authors.lastname: MacGregor
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood / Q000378:metabolism*; D001921:Brain / Q000000981:diagnostic imaging / Q000201:enzymology*; D002531:Cerebellum / Q000000981:diagnostic imaging / Q000201:enzymology; D005260:Female; D019788:Fluorodeoxyglucose F18; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000201:enzymology; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000201:enzymology; D006801:Humans; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000097:blood / Q000378:metabolism*; D014055:Tomography, Emission-Computed
chemical_list: D019788:Fluorodeoxyglucose F18; D008995:Monoamine Oxidase