Whole blood NAD and NADP concentrations are not depressed in subjects with clinical pellagra

Hdl Handle:
http://hdl.handle.net/10144/129972
Title:
Whole blood NAD and NADP concentrations are not depressed in subjects with clinical pellagra
Authors:
Creeke, P I; Dibari, F; Cheung, E; van den Briel, T; Kyroussis, E; Seal, A J
Journal:
Journal of Nutrition
Abstract:
Population surveys for niacin deficiency are normally based on clinical signs or on biochemical measurements of urinary niacin metabolites. Status may also be determined by measurement of whole blood NAD and NADP concentrations. To compare these methods, whole blood samples and spot urine samples were collected from healthy subjects (n = 2) consuming a western diet, from patients (n = 34) diagnosed with pellagra and attending a pellagra clinic in Kuito (central Angola, where niacin deficiency is endemic), and from female community control subjects (n = 107) who had no clinical signs of pellagra. Whole blood NAD and NADP concentrations were measured by microtiter plate-based enzymatic assays and the niacin urinary metabolites 1-methyl-2-pyridone-5-carboxamide (2-PYR) and 1-methylnicotinamide (1-MN) by HPLC. In healthy volunteers, inter- and intra-day variations for NAD and NADP concentrations were much lower than for the urinary metabolites, suggesting a more stable measure of status. However, whole blood concentrations of NAD and NADP or the NAD:NADP ratio were not significantly depressed in clinical pellagra. In contrast, the concentrations of 2-PYR and 1-MN, expressed relative to either creatinine or osmolality, were lower in pellagra patients and markedly higher following treatment. The use of the combined cut-offs (2-PYR <3.0 micromol/mmol creatinine and 1-MN <1.3 micromol/mmol creatinine) gave a sensitivity of 91% and specificity of 72%. In conclusion, whole blood NAD and NADP concentrations gave an erroneously low estimate of niacin deficiency. In contrast, spot urine sample 2-PYR and 1-MN concentrations, relative to creatinine, were a sensitive and specific measure of deficiency.
Affiliation:
Centre for International Health and Development, Institute of Child Health, London, UK; World Food Programme, Luanda, Angola; World Food Programme, Rome, Italy; Medecins sans Frontieres-Belgium, Kuito, Angola
Issue Date:
1-Sep-2007
URI:
http://hdl.handle.net/10144/129972
PubMed ID:
17709435
Additional Links:
http://jn.nutrition.org/cgi/content/full/137/9/2013
Type:
Article
Language:
en
ISSN:
0022-3166
Appears in Collections:
Nutrition

Full metadata record

DC FieldValue Language
dc.contributor.authorCreeke, P Ien
dc.contributor.authorDibari, Fen
dc.contributor.authorCheung, Een
dc.contributor.authorvan den Briel, Ten
dc.contributor.authorKyroussis, Een
dc.contributor.authorSeal, A Jen
dc.date.accessioned2011-05-23T22:33:48Z-
dc.date.available2011-05-23T22:33:48Z-
dc.date.issued2007-09-01-
dc.identifier.citationJ. Nutr. 2007;137(9):2013-7en
dc.identifier.issn0022-3166-
dc.identifier.pmid17709435-
dc.identifier.urihttp://hdl.handle.net/10144/129972-
dc.description.abstractPopulation surveys for niacin deficiency are normally based on clinical signs or on biochemical measurements of urinary niacin metabolites. Status may also be determined by measurement of whole blood NAD and NADP concentrations. To compare these methods, whole blood samples and spot urine samples were collected from healthy subjects (n = 2) consuming a western diet, from patients (n = 34) diagnosed with pellagra and attending a pellagra clinic in Kuito (central Angola, where niacin deficiency is endemic), and from female community control subjects (n = 107) who had no clinical signs of pellagra. Whole blood NAD and NADP concentrations were measured by microtiter plate-based enzymatic assays and the niacin urinary metabolites 1-methyl-2-pyridone-5-carboxamide (2-PYR) and 1-methylnicotinamide (1-MN) by HPLC. In healthy volunteers, inter- and intra-day variations for NAD and NADP concentrations were much lower than for the urinary metabolites, suggesting a more stable measure of status. However, whole blood concentrations of NAD and NADP or the NAD:NADP ratio were not significantly depressed in clinical pellagra. In contrast, the concentrations of 2-PYR and 1-MN, expressed relative to either creatinine or osmolality, were lower in pellagra patients and markedly higher following treatment. The use of the combined cut-offs (2-PYR <3.0 micromol/mmol creatinine and 1-MN <1.3 micromol/mmol creatinine) gave a sensitivity of 91% and specificity of 72%. In conclusion, whole blood NAD and NADP concentrations gave an erroneously low estimate of niacin deficiency. In contrast, spot urine sample 2-PYR and 1-MN concentrations, relative to creatinine, were a sensitive and specific measure of deficiency.en
dc.language.isoenen
dc.relation.urlhttp://jn.nutrition.org/cgi/content/full/137/9/2013en
dc.rightsArchived with thanks to The Journal of Nutrition and the American Society for Nutritionen
dc.subject.meshAdolescenten
dc.subject.meshAdulten
dc.subject.meshFemaleen
dc.subject.meshHumansen
dc.subject.meshMaleen
dc.subject.meshMiddle Ageden
dc.subject.meshNADen
dc.subject.meshNADPen
dc.subject.meshNiacinamideen
dc.subject.meshPellagraen
dc.subject.meshPyridonesen
dc.subject.meshSensitivity and Specificityen
dc.subject.meshTime Factorsen
dc.titleWhole blood NAD and NADP concentrations are not depressed in subjects with clinical pellagraen
dc.typeArticleen
dc.contributor.departmentCentre for International Health and Development, Institute of Child Health, London, UK; World Food Programme, Luanda, Angola; World Food Programme, Rome, Italy; Medecins sans Frontieres-Belgium, Kuito, Angolaen
dc.identifier.journalJournal of Nutritionen
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