title: Optimal and stable conditions for the determination of erythrocyte glutathione reductase activation coefficient to evaluate riboflavin status.
abstract: To measure the activation coefficient (AC) of erythrocyte glutathione reductase (GR), suspended whole blood was lysed in a preincubation solution, with or without 100 microM flavin adenine dinucleotide (FAD). Upon addition of the reaction mixture, FAD concentration decreased about 10-fold. No AC values < 1 were obtained in any of the subjects. The range of unstimulated activity per g hemoglobin (Hb) was 5 to 12 U. AC values of healthy subjects (1.3) decreased to about 1.15 after vitamin supplementation of 1 RDA for 3 wk. In healthy young subjects consumption of dietary riboflavin at levels as low as 0.5 mg/d resulted in an AC of 1.6.
authors.affiliation: Department of Biochemistry, Food Sciences and Nutrition, Faculty of Agriculture-Rehovot, Hebrew University of Jerusalem, Israel.
authors.forename: Y
authors.initials: Y
authors.lastname: Dror
authors.forename: F
authors.initials: F
authors.lastname: Stern
authors.forename: M
authors.initials: M
authors.lastname: Komarnitsky
mesh_terms: D000328:Adult; D001793:Blood Preservation; D004789:Enzyme Activation; D004912:Erythrocytes / Q000201:enzymology*; D005182:Flavin-Adenine Dinucleotide / Q000097:blood; D005980:Glutathione Reductase / Q000097:blood*; D006801:Humans; D009249:NADP / Q000097:blood; D009752:Nutritional Status; D012016:Reference Values; D012256:Riboflavin / Q000008:administration & dosage; D012257:Riboflavin Deficiency / Q000175:diagnosis* / Q000201:enzymology; D014815:Vitamins / Q000008:administration & dosage
chemical_list: D014815:Vitamins; D005182:Flavin-Adenine Dinucleotide; D009249:NADP; D005980:Glutathione Reductase; D012256:Riboflavin