Elevated cerebral glutamate and myo-inositol levels in cognitively normal middle-aged adults with metabolic syndrome.
Metabolic syndrome (MetS) is a cluster of risk factors associated with significant cardiovascular morbidity and mortality and diminished cognitive function. Given that the cerebral mechanisms mediating the relationship between peripheral metabolic dysfunction and cognitive impairment are unknown, we set out to examine the relationship between diagnosis of metabolic syndrome and cerebral metabolism. Thirteen participants with MetS (aged 48 ± 6 years) and 25 healthy adults (aged 51 ± 6 years) underwent neuropsychological assessment, health screen and proton magnetic resonance spectroscopy ((1)H MRS) examining N-acetyl-aspartate (NAA), myo-inositol (mI), creatine (Cr), choline (Cho), and glutamate (Glu) concentrations in occipitoparietal grey matter. Cerebral metabolite ratios (NAA/Cr, Cho/Cr, mI/Cr, and Glu/Cr) of participants with MetS, defined by the International Diabetes Federation criteria, were compared with controls matched for age, education, cognition, and emotional function. There were no significant differences in global cognitive function, memory, language, and psychomotor performance between the groups. Diagnosis of MetS was associated with significantly higher mI/Cr (F(1,36) = 5.02, p = 0.031) and Glu/Cr ratio (F(1,36) = 4.81, p = 0.035). Even in cognitively normal adults, MetS is related to cerebral metabolic disturbances, a possible indication of early brain vulnerability. Longitudinal studies that begin in mid-life can help validate the use of (1)H MRS markers as indicators of long-term cognitive outcomes.
Department of Psychology, The University of Texas at Austin, 1 University Station, A8000, Austin, TX 78712, USA. haley@psy.utexas.edu
Andreana P
AP
Haley
Mitzi M
MM
Gonzales
Takashi
T
Tarumi
Steven C
SC
Miles
Katayoon
K
Goudarzi
Hirofumi
H
Tanaka
D000328:Adult; D001923:Brain Chemistry / Q000502:physiology; D003072:Cognition Disorders / Q000209:etiology / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D006801:Humans; D007294:Inositol / Q000378:metabolism*; D007361:Intelligence Tests; D007802:Language; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008568:Memory / Q000502:physiology; D024821:Metabolic Syndrome / Q000145:classification / Q000378:metabolism* / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010487:Periaqueductal Gray / Q000378:metabolism; D011597:Psychomotor Performance / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D014796:Visual Perception / Q000502:physiology; D014888:Wechsler Scales
D018698:Glutamic Acid; D007294:Inositol