title: Plasma levels of nitric oxide related amino acids in demented subjects with Down syndrome are related to neopterin concentrations.
abstract: Subjects with Down syndrome (DS) have abnormalities in virtually all aspects of the immune system and almost all will be affected with Alzheimer's disease (AD). It is thought that nitric oxide (NO) is involved in the pathophysiology of AD. In the present study, including a total of 401 elderly DS subjects, the spectrum of plasma amino acids and neopterin was investigated and related to development of AD. Concentrations of nearly all amino acids in DS subjects differed significantly from those of healthy controls. Neopterin was increased in DS subjects, especially in dementia. The production of NO as reflected by an increased citrulline/arginine ratio (Cit/Arg ratio) was enhanced during development of clinical dementia. Neopterin concentrations correlated to the Cit/Arg ratio only in the group of prevalent demented subjects (rho = 0.48, P = 0.006). The results of this study are suggestive for an increase in oxidative processes in DS subjects with AD.
authors.affiliation: Centre for the Intellectually Disabled, Dichterbij, Gennep, The Netherlands. a.coppus@erasmusmc.nl
authors.forename: A M W
authors.initials: AM
authors.lastname: Coppus
authors.forename: D
authors.initials: D
authors.lastname: Fekkes
authors.forename: W M A
authors.initials: WM
authors.lastname: Verhoeven
authors.forename: S
authors.initials: S
authors.lastname: Tuinier
authors.forename: C M
authors.initials: CM
authors.lastname: van Duijn
mesh_terms: D000544:Alzheimer Disease / Q000097:blood / Q000150:complications; D000596:Amino Acids / Q000097:blood* / Q000378:metabolism; D024322:Amino Acids, Aromatic / Q000097:blood; D000597:Amino Acids, Branched-Chain / Q000097:blood; D001120:Arginine / Q000097:blood; D002956:Citrulline / Q000097:blood; D015331:Cohort Studies; D003704:Dementia / Q000097:blood* / Q000150:complications / Q000453:epidemiology; D003863:Depression / Q000097:blood / Q000150:complications / Q000188:drug therapy; D004314:Down Syndrome / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D004827:Epilepsy / Q000097:blood / Q000150:complications / Q000188:drug therapy; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D019798:Neopterin / Q000097:blood*; D009569:Nitric Oxide / Q000378:metabolism*; D018384:Oxidative Stress; D012720:Severity of Illness Index
chemical_list: D000596:Amino Acids; D024322:Amino Acids, Aromatic; D000597:Amino Acids, Branched-Chain; D002956:Citrulline; D009569:Nitric Oxide; D019798:Neopterin; D001120:Arginine