title: Pro-oxidant effect of vitamin E in cigarette smokers consuming a high polyunsaturated fat diet.
abstract: Dietary polyunsaturated fats and vitamin E are associated with reduced risk for atherosclerosis, but in smokers, they could promote lipid oxidation. Therefore, we examined the effects of a high polyunsaturated fat diet and vitamin E supplementation on measures of lipid oxidation in cigarette smokers. Ten subjects who smoked >1 pack of cigarettes per day were sequentially fed the following: a baseline diet in which the major fat source was olive oil, a diet in which the major fat source was high-linoleic safflower oil, and finally, the safflower oil diet plus 800 IU vitamin E per day. LDL oxidation lag time and rate and plasma total F(2)-isoprostanes and prostaglandin F(2alpha) (PGF(2alpha)) were determined after 3 weeks on each diet. The safflower oil diet increased total F(2)-isoprostanes from 53.0+/-7.2 to 116.2+/-11.2 nmol/L and PGF(2alpha) from 3.5+/-0.2 to 5.5+/-0.5 nmol/L, without changing LDL oxidation parameters. Addition of vitamin E prolonged mean LDL oxidation lag time but, paradoxically, further increased F(2)-isoprostanes to 188.2+/-10.9 nmol/L and PGF(2alpha) to 7.8+/-0.4 nmol/L. These data suggest that vitamin E may function as a pro-oxidant in cigarette smokers consuming a high polyunsaturated fat diet.
authors.affiliation: Department of Internal Medicine, Section of Gastroenterology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: R B
authors.initials: RB
authors.lastname: Weinberg
authors.forename: B S
authors.initials: BS
authors.lastname: VanderWerken
authors.forename: R A
authors.initials: RA
authors.lastname: Anderson
authors.forename: J E
authors.initials: JE
authors.lastname: Stegner
authors.forename: M J
authors.initials: MJ
authors.lastname: Thomas
mesh_terms: D001161:Arteriosclerosis / Q000209:etiology; D004032:Diet; D019587:Dietary Supplements; D015237:Dinoprost / Q000031:analogs & derivatives / Q000097:blood; D028441:F2-Isoprostanes; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage*; D006801:Humans; D007700:Kinetics; D015227:Lipid Peroxidation; D008077:Lipoproteins, LDL / Q000378:metabolism; D018384:Oxidative Stress; D012907:Smoking / Q000009:adverse effects*; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D028441:F2-Isoprostanes; D005231:Fatty Acids, Unsaturated; D008077:Lipoproteins, LDL; D014810:Vitamin E; D015237:Dinoprost