Age-related increases in brain monoamine oxidase B in living healthy human subjects

Neurobiol Aging. 1997 Jul-Aug;18(4):431-5. doi: 10.1016/s0197-4580(97)00037-7.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Age Distribution
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging / blood
  • Aging / metabolism*
  • Brain / diagnostic imaging
  • Brain / enzymology*
  • Cerebellum / diagnostic imaging
  • Cerebellum / enzymology
  • Female
  • Fluorodeoxyglucose F18
  • Frontal Lobe / diagnostic imaging
  • Frontal Lobe / enzymology
  • Gyrus Cinguli / diagnostic imaging
  • Gyrus Cinguli / enzymology
  • Humans
  • Male
  • Mathematics
  • Middle Aged
  • Monoamine Oxidase / blood
  • Monoamine Oxidase / metabolism*
  • Tomography, Emission-Computed


  • Fluorodeoxyglucose F18
  • Monoamine Oxidase