Effect of long-term vitamin E and selenium supplementation on urine F2-isoprostanes, a biomarker of

BACKGROUND:

Cigarette smoking generates reactive oxidant species and contributes to systemic oxidative stress, which plays a role in the pathophysiology of chronic diseases. Nutrients with antioxidant properties, including vitamin E and selenium, are proposed to reduce systemic oxidative burden and thus to mitigate the negative health effects of reactive oxidant species.
OBJECTIVE:

Our objective was to determine whether long-term supplementation with vitamin E and/or selenium reduces oxidative stress in smokers, as measured by urine 8-iso-prostaglandin F2-alpha (8-iso-PGF2α).
DESIGN:

We measured urine 8-iso-PGF2α with competitive enzyme linked immunoassay (ELISA) in 312 male current smokers after 36 months of intervention in a randomized placebo-controlled trial of vitamin E (400IU/d all rac-α-tocopheryl acetate) and/or selenium (200µg/d L-selenomethionine). We used linear regression to estimate the effect of intervention on urine 8-iso-PGF2α, with adjustments for age and race.
RESULTS:

Compared to placebo, vitamin E alone lowered urine 8-iso-PGF2α by 21% (p=0.02), there was no effect of combined vitamin E and selenium (intervention arm lower by 9%; p=0.37) or selenium alone (intervention arm higher by 8%; p=0.52).
CONCLUSIONS:

Long-term vitamin E supplementation decreases urine 8-iso-PGF2α among male cigarette smokers, but we observed little to no evidence for an effect of selenium supplementation, alone or combined with vitamin E.

Copyright © 2016 Elsevier Inc. All rights reserved.
KEYWORDS:

Alpha-tocopherol; Antioxidant nutrients; Chronic obstructive pulmonary disease; Cigarette smoking; Isoprostanes; Lipid peroxidation; Lung function; Oxidative stress; Randomized controlled trial; Selenium; Vitamin E