Inhibitory effect of wheat bran feruloyl oligosaccharides on oxidative DNA damage in human lymphocytes

The present work assessed the protective effect of feruloyl oligosaccharides (FOs), the ferulic acid ester of oligosaccharides from wheat bran, against oxidative DNA damage in normal human peripheral blood lymphocytes induced by hydrogen peroxide (H2O2). The DNA damage was measured by using the single cell gel electrophoresis assay (comet assay). Lymphocytes were subjected to DNA damage by exposure to a range of H2O2 concentrations (10-200 mu mol/l). H2O2, at a concentration of 200 mu mol/l, resulted in nearly all cells being highly damaged. FOs showed no cytotoxicity and genotoxicity to normal human lymphocytes at the tested concentrations (10500 mu mol/l). In addition, DNA damage in human lymphocytes induced by 100 mu mol/l H2O2 was inhibited by FOs in a concentration-dependent fashion with 91.1% inhibition of lymphocyte DNA damage at 500 mu mol/l as compared with the control. The results suggest that water-soluble Fos from wheat bran are able to enhance the ability of human lymphocytes to resist H2O2 induced oxidative damage. (c) 2007 Elsevier Ltd. All rights reserved.