Antioxidant micronutrients and biomarkers of oxidative stress and inflammation in
colorectal adenoma patients: results from a randomized, controlled clinical
trial.
Author(s): Hopkins MH, Fedirko V, Jones DP, Terry PD, Bostick RM.
Affiliation(s): Department of Epidemiology, Rollins School of Public Health, Emory University,
Atlanta, GA 30322, USA.
Publication date & source: 2010, Cancer Epidemiol Biomarkers Prev. , 19(3):850-8
Previous epidemiologic observational and experimental studies investigated the
potential of antioxidant micronutrients to modulate cancer risk, but these
studies produced inconsistent results. In this pilot, randomized, double-blind,
placebo-controlled clinical trial (n = 47), we assessed the effects of an
antioxidant micronutrient combination (800 mg dl-alpha-tocopherol acetate, 24 mg
beta-carotene, 1.0 g vitamin C, 200 microg l-selenomethionine, 7.2 mg riboflavin,
80 mg niacin, 60 mg zinc, 5 mg manganese) given daily over 4 months on oxidative
and inflammatory biomarkers in patients with a history of sporadic colorectal
adenoma. Plasma tumor necrosis factor-alpha (TNF-alpha), interleukin-6, and
F2-isoprostane concentrations were measured using ELISAs, and cystine (CySS) was
measured using high-performance liquid chromatography. Plasma TNF-alpha
concentration decreased in the active treatment group by 37% relative to the
placebo group (P = 0.002), and CySS decreased by 19% (P = 0.03); however,
interleukin-6 and F2-isoprostane concentrations decreased in antioxidant-treated
nonsmokers but increased in smokers, although these findings were not
statistically significant. The decreases of TNF-alpha and CySS were more
pronounced in nonsmokers. These data suggest that (a) an antioxidant
micronutrient cocktail can modulate biomarkers of oxidative stress and
inflammation in humans and (b) the effects of antioxidant micronutrient
supplementation on biomarkers of inflammation and oxidative stress may differ
according to smoking status.
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