title: Edited Magnetic Resonance Spectroscopy Detects an Age-Related Decline in Nonhuman Primate Brain GABA Levels.
abstract: Recent research had shown a correlation between aging and decreasing Gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the brain. However, how GABA level varies with age in the medial portion of the brain has not yet been studied. The purpose of this study was to investigate the GABA level variation with age focusing on the posterior cingulate cortex, which is the "core hub" of the default mode network. In this study, 14 monkeys between 4 and 21 years were recruited, and MEGA-PRESS MRS was performed to measure GABA levels, in order to explore a potential link between aging and GABA. Our results showed that a correlation between age and GABA+/Creatine ratio was at the edge of significance (r= -0.523,p= 0.081). There was also a near-significant trend between gray matter/white matter ratio and the GABA+/Creatine ratio (r= -0.518,p= 0.0848). Meanwhile, the correlation between age and grey matter showed no significance (r= -0.028,p= 0.93). Therefore, age and gray matter/white matter ratio account for different part ofR-squared (adjustedR-squared = 0.5187) as independent variables for predicting GABA levels. AdjustedR-squared is about 0.5 for two independent variables. These findings suggest that there is internal neurochemical variation of GABA levels in the nonhuman primates associated with normal aging and structural brain decline.
authors.affiliation: Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA.
authors.forename: Xuanzi
authors.identifier: 0000-0002-2017-9226
authors.initials: X
authors.lastname: He
authors.affiliation: Department of Anatomy and Neurobiology, Boston University School of Medicine, 620 Albany St., Boston, MA 02118, USA.
authors.forename: Bang-Bon
authors.identifier: 0000-0001-7423-5572
authors.initials: BB
authors.lastname: Koo
authors.affiliation: Department of Anatomy and Neurobiology, Boston University School of Medicine, 620 Albany St., Boston, MA 02118, USA.
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Killiany