The relationship between dose of vitamin E and suppression of oxidative stress in humans

L. Jackson Roberts, John A. Oates, MacRae F. Linton, Sergio Fazio, Beth P. Meador, Myron D. Gross, Yu Shyr, Jason D. Morrow

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    173 Scopus citations

    Abstract

    The oxidation hypothesis of atherogenesis has been the focus of much research over the past 2 decades. However, randomized placebo-controlled trials evaluating the efficacy of vitamin E in preventing cardiovascular events in aggregate have failed to show a beneficial effect. Implicit in these trials is that the dose of vitamin E tested effectively suppressed oxidative stress status but this was never determined. We defined the dose-dependent effects of vitamin E (RRR-α-tocopherol) to suppress plasma concentrations of F2-isoprostanes, a biomarker of free radical-mediated lipid peroxidation, in participants with polygenic hypercholesterolemia and enhanced oxidative stress, a population at risk for cardiovascular events. A time-course study was first performed in participants supplemented with 3200 IU/day of vitamin E for 20 weeks. A dose-ranging study was then performed in participants supplemented with 0, 100, 200, 400, 800, 1600, or 3200 IU/day of vitamin E for 16 weeks. In the time-course study, maximum suppression of plasma F2-isoprostane concentrations did not occur until 16 weeks of supplementation. In the dose-ranging study there was a linear trend between the dosage of vitamin E and percentage reduction in plasma F2-isoprostane concentrations which reached significance at doses of 1600 IU (35 ± 2%, p < 0.035) and 3200 IU (49 ± 10%, p < 0.005). This study provides information on the dosage of vitamin E that decreases systemic oxidant stress in vivo in humans and informs the planning and evaluation of clinical studies that assess the efficacy of vitamin E to mitigate disease.

    Original languageEnglish (US)
    Pages (from-to)1388-1393
    Number of pages6
    JournalFree Radical Biology and Medicine
    Volume43
    Issue number10
    DOIs
    StatePublished - Nov 15 2007

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    Keywords

    • Cardiovascular disease
    • Free radicals
    • Hypercholesterolemia
    • Isoprostane
    • Oxidative stress
    • Vitamin E

    ASJC Scopus subject areas

    • Biochemistry
    • Physiology (medical)

    Cite this

    Roberts, L. J., Oates, J. A., Linton, M. F., Fazio, S., Meador, B. P., Gross, M. D., Shyr, Y., & Morrow, J. D. (2007). The relationship between dose of vitamin E and suppression of oxidative stress in humans. Free Radical Biology and Medicine, 43(10), 1388-1393. https://doi.org/10.1016/j.freeradbiomed.2007.06.019