Modification of lymphocyte DNA damage by carotenoid supplementation in postmenopausal women

Abstract

Background: Oxidative stress has been implicated in the pathogenesis of chronic diseases related to aging such as cancer and cardiovascular disease. Carotenoids could be a part of a protective strategy to minimize oxidative damage in vulnerable populations, such as the elderly. Objective: Our aim was to determine the protective effect of carotenoids against DNA damage. Design: A randomized, double-blind, placebo-controlled intervention study was conducted. Thirty-seven healthy, nonsmoking postmenopausal women aged 50-70 y were randomly assigned to 1 of 5 groups and were instructed to consume a daily dose of mixed carotenoids (β-carotene, lutein, and lycopene; 4 mg each), 12 mg of a single carotenoid (β-carotene, lutein, or lycopene), or placebo for 56 d. Plasma carotenoid concentrations were analyzed by using HPLC, and lymphocyte DNA damage was measured by using a single-cell gel electrophoresis (comet) assay. Results: At day 57, all carotenoid-supplemented groups showed significantly lower endogenous DNA damage than at baseline (P < 0.01), whereas the placebo group did not show any significant change. Significantly less (P < 0.05) endogenous DNA damage was found as early as day 15 in the mixed carotenoid (P < 0.01) and β-carotene (P < 0.05) groups. Conclusions: The results indicate that carotenoid supplementation decreases DNA damage and that a combination of carotenoids (4 mg each of lutein, β-carotene, and lycopene), an intake that can be achieved by diet, or a larger dose (12 mg) of individual carotenoids exerts protection against DNA damage. © 2006 American Society for Nutrition.