Plasma levels of nitric oxide related amino acids in demented subjects with Down syndrome are related to neopterin concentrations

• Published in: Amino acids Vol. 38; no. 3; pp. 923 - 928
• Main Authors: Coppus, A. M. W., Fekkes, D., Verhoeven, W. M. A., Tuinier, S., van Duijn, C. M.
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.03.2010; Springer Nature B.V
• Subjects: Abnormalities; Alzheimer disease; Alzheimer Disease - blood; Alzheimer Disease - complications; Alzheimer's disease; Amino acids; Amino Acids - blood; Amino Acids - metabolism; Amino Acids, Aromatic - blood; Amino Acids, Branched-Chain - blood; Analytical Chemistry; arginine; Arginine - blood; Biochemical Engineering; Biochemistry; Biomedical and Life Sciences; Citrulline; Citrulline - blood; Cohort Studies; Control equipment; Correlation; Dementia - blood; Dementia - complications; Dementia - epidemiology; Dementia disorders; Depression - blood; Depression - complications; Depression - drug therapy; Down syndrome; Down Syndrome - blood; Down Syndrome - complications; Down Syndrome - physiopathology; Down's syndrome; elderly; Epilepsy - blood; Epilepsy - complications; Epilepsy - drug therapy; Female; Humans; Immune system; Immune systems; Intellectual Disability - physiopathology; Life Sciences; Male; Medical research; Middle Aged; Neopterin; Neopterin - blood; Neurobiology; Neurodegenerative diseases; Nitric oxide; Nitric Oxide - metabolism; Original; Original Article; Oxidative Stress; pathophysiology; Plasma levels; Proteomics; Severity of Illness Index; Amino acids; Down syndrome; Neopterin; Branched chain amino acids; Nitric oxide
• ISSN: 0939-4451; 1438-2199; 1438-2199
• DOI: 10.1007/s00726-009-0300-5

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 ( ρ  = 0.48, P  = 0.006). The results of this study are suggestive for an increase in oxidative processes in DS subjects with AD.