Amino acid metabolic processes in the temporal lobes assessed by proton magnetic resonance spectroscopy (1Η MRS) in children with Down syndrome

Down syndrome (DS), or trisomy 21, is one of the most common autosomal mutations. The overexpression of the β-amyloid precursor protein gene, located on chromosome 21, causes an increased production of the specific amyloid. The current study is a continuation of our earlier investigations relating to the profile of metabolic changes in the frontal lobes of DS patients as assessed by proton magnetic resonance spectroscopy (1H MRS). The aims of the study were the morphological assessment of the brain using magnetic resonance imaging (MRI) and the evaluation of metabolic disorders of the temporal lobes using 1H MRS in DS children. The study group included 20 children with DS aged 3–15 years and treated in the Department of Pediatric Neurology and Rehabilitation, Medical University of Bialystok. The control group included healthy children (n = 20). MRI scans of the heads of DS children were performed using a 1.5 T MR scanner under standard conditions. 1H MRS investigations were also carried out to assess metabolic changes in the temporal lobes. Metabolites, such as N-acetylaspartate (NAA), glutamate-glutamine complex (Glx), choline (Cho), myoinositol (ml) and γ-aminobutyric acid (GABA), were determined in both temporal lobes with reference to the internal marker creatine (Cr). Results were compared with the control group. We found a statistically significant decrease in NAA/Cr, Cho/Cr, ml/Cr and GABA/Cr ratios. The Glx/Cr ratio in both temporal lobes of DS patients did not differ from the control group. Our results indicate metabolic neurotransmitter disorders in the central nervous system in children with DS.