Prevention of DNA damage by polyphenol‐rich food

Abstract

Epidemiological and experimental data suggest that an increased intake of plant food rich in polyphenols can reduce the risk of cancers. DNA damage is an important step in the initiation of carcinogenesis. Here we report data on the effect of polyphenol rich food such as apples and apple juice on DNA damage in colon epithelial cells from animal studies and in peripheral blood lymphocytes (PBL) from human intervention studies.1,2‐Dimethylhydrazine‐induced DNA strand breaks in colon epithelial cells in rats were significantly inhibited by consumption of cloudy and clear apple juice. In a human intervention study, consumption of 1 kg apples caused no changes in endogenous DNA strand breaks, in Fpg‐sensitive sites (oxidative purine damage) or in the capacity to protect DNA against damage induced by hydrogen peroxide in PBL. But, a statistically significant decrease in the levels of endonuclease III sensitive sites (oxidative pyrimidine damage) and an increase in capacity to protect DNA against strand breaks induced by iron chloride were identified. In contrast to the effects of apples, a human intervention with 2, 5 or 8 servings of fruit and vegetables/day had no effect on DNA damage in PBL. Thus, we have identified apples as another fruit to add to the already known types of fruit (kiwi) and vegetables (tomato) with antigenotoxic properties and partly characterized their antigenotoxic mechanism in humans.Supported by the Deutsche Forschungsgemeinschaft and the Federal Ministry of Research and Education, Germany