title: Cigarette smokers have decreased lymphocyte and platelet alpha-tocopherol levels and increased excretion of the gamma-tocopherol metabolite gamma-carboxyethyl-hydroxychroman (gamma-CEHC).
abstract: Cigarette smoking is associated with increased oxidative stress and increased risk of degenerative disease. As the major lipophilic antioxidant, requirements for vitamin E may be higher in smokers due to increased utilisation. In this observational study we have compared vitamin E status in smokers and non-smokers using a holistic approach by measuring plasma, erythrocyte, lymphocyte and platelet alpha- and gamma-tocopherol, as well as the specific urinary vitamin E metabolites alpha- and gamma-carboxyethyl-hydroxychroman (CEHC). Fifteen smokers (average age 27 years, smoking time 7.5 years) and non-smokers of comparable age, gender and body mass index (BMI) were recruited. Subjects completed a 7-day food diary and on the final day they provided a 24 h urine collection and a 20 ml blood sample for measurement of urinary vitamin E metabolites and total vitamin E in blood components, respectively. No significant differences were found between plasma and erythrocyte alpha- and gamma-tocopherol in smokers and non-smokers. However, smokers had significantly lower alpha-tocopherol (mean+/-SD, 1.34+/-0.31 micromol/g protein compared with 1.94+/-0.54, P = 0.001) and gamma-tocopherol (0.19+/-0.04 micromol/g protein compared with 0.26+/-0.08, P = 0.026) levels in their lymphocytes, as well as significantly lower alpha-tocopherol levels in platelets (1.09+/-0.49 micromol/g protein compared with 1.60+/-0.55, P = 0.014; gamma-tocopherol levels were similar). Interestingly smokers also had significantly higher excretion of the urinary gamma-tocopherol metabolite, gamma-CEHC (0.49+/-0.25mg/g creatinine compared with 0.32+/-0.16, P = 0.036) compared to non-smokers, while their alpha-CEHC (metabolite of alpha-tocopherol) levels were similar. There was no significant difference between plasma ascorbate, urate and F2-isoprostane levels. Therefore in this population of cigarette smokers (mean age 27 years, mean smoking duration 7.5 years), alterations to vitamin E status can be observed even without the more characteristic changes to ascorbate and F2-isoprostanes. We suggest that the measurement of lymphocyte and platelet vitamin E may represent a valuable biomarker of vitamin E status in relation to oxidative stress conditions.
authors.affiliation: Centre for Nutrition and Food Safety, School of Biomedical and Molecular Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK.
authors.forename: Yvonne M
authors.initials: YM
authors.lastname: Jeanes
authors.forename: Wendy L
authors.initials: WL
authors.lastname: Hall
authors.forename: Anna R
authors.initials: AR
authors.lastname: Proteggente
authors.forename: John K
authors.initials: JK
authors.lastname: Lodge
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D001205:Ascorbic Acid / Q000097:blood; D001792:Blood Platelets / Q000378:metabolism*; D002839:Chromans / Q000097:blood* / Q000378:metabolism / Q000652:urine; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000097:blood; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000166:cytology / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011422:Propionates / Q000097:blood* / Q000378:metabolism / Q000652:urine; D012907:Smoking / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D014527:Uric Acid / Q000097:blood; D024502:alpha-Tocopherol / Q000097:blood* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002839:Chromans; D011422:Propionates; C107690:2,7,8-trimethyl-2-(beta-carboxyethyl)-6-hydroxychroman; D014527:Uric Acid; C075750:8-epi-prostaglandin F2alpha; C084852:2,5,7,8-tetramethyl-2-(2'-carboxyethyl)-6-hydroxychroman; D015237:Dinoprost; D024502:alpha-Tocopherol; D001205:Ascorbic Acid