title: Age-related increase of resting metabolic rate in the human brain.
abstract: With age, many aspects of the brain structure undergo a pronounced decline, yet individuals generally function well until advanced old age. There appear to be several compensatory mechanisms in brain aging, but their precise nature is not well characterized. Here we provide evidence that the brain of older adults expends more energy when compared to younger adults, as manifested by an age-related increase (P=0.03) in cerebral metabolic rate of oxygen (CMRO2) (N=118, men=56, ages 18 to 74). We further showed that, before the mean menopausal age of 51years old, female and male groups have similar rates of CMRO2 increase (P=0.015) and there was no interaction between age and sex effects (P=0.85). However, when using data from the entire age range, women have a slower rate of CMRO2 change when compared to men (P<0.001 for age×sex interaction term). Thus, menopause and estrogen level may have played a role in this sex difference. Our data also revealed a possible circadian rhythm of CMRO2 in that brain metabolic rate is greater at noon than in the morning (P=0.02). This study reveals a potential neurobiological mechanism for age-related compensation in brain function and also suggests a sex-difference in its temporal pattern.
authors.affiliation: Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Shin-Lei
authors.initials: SL
authors.lastname: Peng
authors.affiliation: Clinical Neuroscience Research Unit, Department of Psychiatry, University of Vermont College of Medicine, Burlington, VT 05401, USA.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Dumas
authors.affiliation: Center for Vital Longevity, UT Dallas, Dallas, TX 75235, USA; Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Denise C
authors.initials: DC
authors.lastname: Park
authors.affiliation: Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Peiying
authors.initials: P
authors.lastname: Liu
authors.affiliation: Center for Brain Health, School of Behavioral and Brain Sciences, UT Dallas, Dallas, TX 75235, USA.
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Filbey
authors.affiliation: Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
authors.forename: Carrie J
authors.initials: CJ
authors.lastname: McAdams
authors.affiliation: Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Psychology, Southern Methodist University, Dallas, TX 75275, USA.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Pinkham
authors.affiliation: Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA; VA North Texas Health Care System, Dallas, TX 75216, USA.
authors.forename: Bryon
authors.initials: B
authors.lastname: Adinoff
authors.affiliation: Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX 75231, USA.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA. Electronic address: Hanzhang.lu@utsouthwestern.edu.
authors.forename: Hanzhang
authors.initials: H
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001481:Basal Metabolism; D001921:Brain / Q000098:blood supply / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism*; D012737:Sex Factors; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Blood oxygenation; Cerebral blood flow; Cerebral metabolism; MRI; TRUST