Kiwifruit Protects Against Oxidative DNA Damage in Human Cells and In Vitro

Abstract

Antioxidant micronutrients may account for the beneficial effects of fruits on human health. A direct demonstration that consumption of fruit decreases oxidative DNA damage in human cells would support this hypothesis. Kiwifruit was taken as an example of a food with putative antioxidant properties, and its effectiveness at decreasing oxidative DNA damage was assessed in ex vivo as well as in vitro tests. The comet assay (single-cell gel electrophoresis) was used to measure DNA damage in lymphocytes collected during a human supplementation trial with a single 0.5-liter drink of kiwifruit juice (with water as a control). The comet assay was also modified to assess the antioxidant effect of kiwifruit in vitro by measuring the ability of an extract to interfere with oxidative damage to DNA induced by H2 O2. Ex vivo, consumption of kiwifruit led to an increased resistance of DNA to oxidative damage induced by H2 O2 in isolated lymphocytes, in comparison with lymphocytes collected after a control drink of wate...