phosphocreatine and Asperger-Syndrome

People with autistic spectrum disorders (ASD, including Asperger syndrome) may have developmental abnormalities in the amygdala-hippocampal complex (AHC). However, in vivo, age-related comparisons of both volume and neuronal integrity of the AHC have not yet been carried out in people with Asperger syndrome (AS) versus controls. We compared structure and metabolic activity of the right AHC of 22 individuals with AS and 22 healthy controls aged 10-50 years and examined the effects of age between groups. We used structural magnetic resonance imaging (sMRI) to measure the volume of the AHC, and magnetic resonance spectroscopy ((1)H-MRS) to measure concentrations of N-acetyl aspartate (NAA), creatine+phosphocreatine (Cr+PCr), myo-inositol (mI) and choline (Cho). The bulk volume of the amygdala and the hippocampus did not differ significantly between groups, but there was a significant difference in the effect of age on the hippocampus in controls. Compared with controls, young (but not older) people with AS had a significantly higher AHC concentration of NAA and a significantly higher NAA/Cr ratio. People with AS, but not controls, had a significant age-related reduction in NAA and the NAA/Cr ratio. Also, in people with AS, but not controls, there was a significant relationship between concentrations of choline and age so that choline concentrations reduced with age. We therefore suggest that people with AS have significant differences in neuronal and lipid membrane integrity and maturation of the AHC.

Topics: Adolescent; Adult; Age Factors; Aging; Amygdala; Aspartic Acid; Asperger Syndrome; Brain Mapping; Child; Choline; Creatine; Female; Hippocampus; Humans; Image Processing, Computer-Assisted; Inositol; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Male; Middle Aged; Phosphocreatine

Amygdala dysfunction has been proposed as a critical contributor to social impairment in autism spectrum disorders (ASD). The current study investigated biochemical abnormalities in the amygdala in 20 high functioning adults with autistic disorder or Asperger's disorder and 19 typically developing adults matched on age and IQ. Magnetic resonance spectroscopy was used to measure N-acetyl aspartate (NAA), creatine/phosphocreatine (Cre), choline/choline containing compounds (Cho), and Myoinositol (mI) in the right and left amygdala. There were no significant between-group differences in any of the metabolites. However, NAA and Cre levels were significantly correlated to clinical ratings on the Autism Diagnostic Interview-Revised. This suggests that altered metabolite levels in the amygdala may be associated with a more severe early developmental course in ASD.

Topics: Adolescent; Adult; Amygdala; Aspartic Acid; Asperger Syndrome; Autistic Disorder; Brain Mapping; Case-Control Studies; Choline; Creatine; Female; Functional Laterality; Humans; Image Processing, Computer-Assisted; Inositol; Magnetic Resonance Spectroscopy; Male; Phosphocreatine; Prognosis; Severity of Illness Index; Time Factors; Young Adult

Asperger syndrome (AS; an autistic disorder) is associated with impaired social skills and obsessional/repetitive behavior. Patients with autism have significant abnormalities in the frontal lobe and frontoparietal connectivity. Nobody has examined the relationship between abnormalities in the frontal and parietal lobes and clinical symptoms in people with AS.. We used in vivo proton magnetic resonance spectroscopy to examine neuronal integrity of the medial prefrontal and parietal lobes in 14 non-learning-disabled adults with AS and 18 control subjects (of similar sex, age, and IQ). We obtained measures of the prefrontal lobe in 11, the parietal lobe in 13, and both lobes in 10 subjects with AS. We measured concentrations and ratios of N-acetylaspartate (NAA), creatine and phosphocreatine (Cr + PCr), and choline (Cho). Levels of NAA, Cr + PCr, and Cho are indicators of neuronal density and mitochondrial metabolism, phosphate metabolism, and membrane turnover. Frontal metabolite levels were correlated with scores on the Yale-Brown Obsessive Compulsive Scale and the Autism Diagnostic Interview.. Subjects with AS had a significantly higher prefrontal lobe concentration of NAA (z = -3.1; P =.002), Cr + PCr (z = -2.2; P =.03), and Cho (z = -2.9; P =.003). Increased prefrontal NAA concentration was significantly correlated with obsessional behavior (tau = 0.67; P =.005); increased prefrontal concentration of Cho, with social function (tau = 0.72; P =.02). We found no significant differences in parietal lobe metabolite concentrations.. Subjects with AS have abnormalities in neuronal integrity of the prefrontal lobe, which is related to severity of clinical symptoms.

Topics: Adult; Aspartic Acid; Asperger Syndrome; Brain; Choline; Creatine; Humans; Magnetic Resonance Spectroscopy; Male; Obsessive Behavior; Parietal Lobe; Phosphocreatine; Prefrontal Cortex; Psychiatric Status Rating Scales; Severity of Illness Index