Paper out: Longitudinal increases of brain metabolite levels in 5-10 year old children
In a longitudinal MRS study of 64 South African children aged 5 to 10 years old (29 female; 29 HIV exposed, uninfected), that authors examined the age-related trajectories of creatine (Cr+PCr), N-acetyl-aspartate (NAA), the combined NAA+N-acetyl-aspartyl-glutamate (NAAG), choline (GPC+PCh), glutamate (Glu) and the combined Glu+glutamine (Glu+Gln) in voxels within gray and white matter, as well as subcortically in the basal ganglia (BG). In frontal gray matter, the authors found age-related increases in Cr+PCr, NAA, NAA+NAAG and Glu+Gln levels pointing to synaptic activity likely related to learning. In the BG the authors observed increased levels of Glu, Glu+Gln and NAA+NAAG with age that point to subcortical synaptic reorganization. In white matter, the authors found increased levels of Cr+PCr, NAA, NAA+NAAG, Glu and Glu+Gln with age, implicating these metabolites in ongoing myelination. The authors observed no sex-age or HIV exposure-age interactions, indicating that physiological changes are independent of sex during this time period. The metabolite trajectories presented, therefore, provide a critical benchmark of normal cellular growth for a low socioeconomic pediatric population in the developing world against which pathology and abnormal development may be compared.