Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004352 (autism)
 32,579 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Autism is an early onset developmental disorder with a severe life-long impact on behavior and social functioning that has associated metabolic abnormalities. The urinary metabolic phenotypes of individuals (age range=3-9 years old) diagnosed with autism using the DSM-IV-TR criteria (n = 39; male = 35; female = 4), together with their nonautistic siblings (n = 28; male = 14; female = 14) and age-matched healthy volunteers (n = 34, male = 17; female = 17) have been characterized for the first time using (1)H NMR spectroscopy and pattern recognition methods. Novel findings associated with alterations in nicotinic acid metabolism within autistic individuals showing increased urinary excretion of N-methyl-2-pyridone-5-carboxamide, N-methyl nicotinic acid, and N-methyl nicotinamide indicate a perturbation in the tryptophan-nicotinic acid metabolic pathway. Multivariate statistical analysis indicated urinary patterns of the free amino acids, glutamate and taurine were significantly different between groups with the autistic children showing higher levels of urinary taurine and a lower level of urinary glutamate, indicating perturbation in sulfur and amino acid metabolism in these children. Additionally, metabolic phenotype (metabotype) differences were observed between autistic and control children, which were associated with perturbations in the relative patterns of urinary mammalian-microbial cometabolites including dimethylamine, hippurate, and phenyacetylglutamine. These biochemical changes are consistent with some of the known abnormalities of gut microbiota found in autistic individuals and the associated gastrointestinal dysfunction and may be of value in monitoring the success of therapeutic interventions.
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PMID:Urinary metabolic phenotyping differentiates children with autism from their unaffected siblings and age-matched controls. 2033 4

Methylation, a methyl group-consuming reaction, plays a key role in the degradation (i.e., inactivation) of monoamine neurotransmitters, including catecholamines, serotonin and histamine. Without labile methyl groups, the methylation-mediated degradation cannot take place. Although high niacin (nicotinic acid and nicotinamide) intake, which is very common nowadays, is known to deplete the body's methyl-group pool, its effect on monoamine-neurotransmitter degradation is not well understood. The aim of this article was to investigate the effect of excess nicotinamide on the levels of plasma serotonin and histamine in healthy subjects. Urine and venous blood samples were collected from nine healthy male volunteers before and after oral loading with 100 mg nicotinamide. Plasma N(1)-methylnicotinamide, urinary N(1)-methyl-2-pyridone-5-carboxamide (2-Py), and plasma betaine levels were measured by using high-performance liquid chromatography (HPLC). Plasma concentrations of choline, serotonin and histamine were measured using commercial kits. The results showed that the plasma N(1)-methylnicotinamide level and the urinary excretion of 2-Py significantly increased after oral loading with 100 mg nicotinamide, which was accompanied with a decrease in the methyl-group donor betaine. Compared with those before nicotinamide load, five-hour postload plasma serotonin and histamine levels significantly increased. These results suggest that excess nicotinamide can disturb monoamine-neurotransmitter metabolism. These findings may be of significance in understanding the etiology of monoamine-related mental diseases, such as schizophrenia and autism (a neurodevelopmental disorder).
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PMID:Excess nicotinamide increases plasma serotonin and histamine levels. 2342 11