Antigenotoxic effect of grape seed procyanidin extract in Fao cells submitted to oxidative stress

The protective effects of grape seed procyanidin extract on the repair of H2O2-induced DNA lesions were tested using Fao cells. Cells were exposed to 600 muM H2O2 for 3 or 21 h. A procyanidin extract from grape seed (PE) was incubated or preincubated (1 h) during the exposure to H2O2. The ability of procyanidins to protect against the genotoxicity of H2O2 was compared with those of the monomeric flavanols (+)-catechin and (-)-epicatechin and the flavonol quercetin. After treatment, DNA damage was monitored using alkaline single-cell gel electrophoresis (the comet assay) (Aherne, S. A.; O'Brien, N. M. Nutr. Cancer 1999, 34, 160-166). At the end of the experiment, PE significantly decreased the damage caused by H2O2. The results also showed that quercetin was the most effective of the flavonoids tested, which is consistent with its powerful antioxidant character. The results indicate that procyanidins are more effective than the corresponding individual monomers, catechin and epicatechin, at preventing DNA lesions in hepatocytes and that this protection is higher after preincubation than after co-incubation.