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{alpha}-Tocopherol disappearance is faster in cigarette smokers and is inversely related to their ascorbic acid status.
- Source :
-
The American journal of clinical nutrition [Am J Clin Nutr] 2005 Jan; Vol. 81 (1), pp. 95-103. - Publication Year :
- 2005
-
Abstract
- Background: Cigarette smokers have enhanced oxidative stress from cigarette smoke exposure and from their increased inflammatory responses.<br />Objective: The objective of this study was to determine whether cigarette smoking increases plasma alpha-tocopherol disappearance in otherwise healthy humans.<br />Design: Smokers and nonsmokers (n = 10/group) were supplemented with deuterium-labeled alpha-tocopheryl acetates (75 mg each of d(3)-RRR-alpha-tocopheryl acetate and d(6)-all-rac-alpha-tocopherols acetate) for 6 evenings (days -6 to -1). Plasma alpha-tocopherols, ascorbic acid, uric acid, and F(2alpha)-isoprostanes were measured in blood samples collected on days -6 through 17. The urinary alpha-tocopherol metabolite, alpha-carboxy-ethyl-hydroxy-chroman (alpha-CEHC), was measured on days -6, 0, and 17 in 24-h urine samples.<br />Results: F(2alpha)-isoprostanes were, on average, approximately 40% higher in smokers than in nonsmokers. On day 0, plasma labeled and unlabeled alpha-tocopherol concentrations were not significantly different between groups. Smoking resulted in faster fractional disappearance of plasma alpha-tocopherol (0.215 +/- 0.011 compared with 0.191 +/- 0.009 pools/d; P < 0.05). Fractional disappearance rates of alpha-tocopherol correlated with plasma ascorbic acid concentrations in smokers (P = 0.021) but not in nonsmokers despite plasma ascorbic acid concentrations that were not significantly different between groups. By day 17, cigarette smoking resulted in lower plasma alpha-tocopherol concentrations and urinary excretion of labeled and unlabeled alpha-CEHC (P < 0.05).<br />Conclusions: Cigarette smoking increased alpha-tocopherol disappearance. Greater rates of alpha-tocopherol disappearance in smokers appear to be related to increased oxidative stress accompanied by lower plasma ascorbic acid concentrations. Thus, smokers have an increased requirement for both alpha-tocopherol and ascorbic acid.
Details
- Language :
- English
- ISSN :
- 0002-9165
- Volume :
- 81
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- The American journal of clinical nutrition
- Publication Type :
- Academic Journal
- Accession number :
- 15640466
- Full Text :
- https://doi.org/10.1093/ajcn/81.1.95