When the generation of prooxidants greatly exceeds the cell's capacity to protect itself, serious oxidative stress occurs, and the accumulation of oxidative damages result in pathophysiologic conditions such as coronary artery disease, stroke, and cancer. Epidemiological evidences have suggested that diets rich in fruits and vegetables are associated with a reduced risk for these pathological conditions. Anthocyanins are polyphenolic ring-based flavonoids contained in fruits and vegetables of red-blue color. In cherries and plums, anthocyanins make a major contribution to total antioxidant capacity. Recent studies have indicated that anthocyanins may contribute to cancer chemoprevention. In this study, we investigated the effects of a short-term supplementation with cherries and plums on oxidative stress markers which are directly or indirectly related to the cancer initiation, promotion and progression. Healthy volunteers (n=12) received 530 g of fresh cherries and 450 g of plums on daily basis for 2 weeks. Before and after the supplementation, plasma F₂-isoprostane, α-tocopherol, FRAP, and lymphocyte DNA damages were measured. Serum levels of total cholesterol, HDL-cholesterol, LDL-cholesterol and TG were also measured. During the study period, no significant difference was found in the mean dietary intake of energy, carbohydrate, protein, and fat. Results indicated that supplementation significantly increased plasma α-tocopherol concentration and ferric reducing ability of plasma (FRAP). F₂-isoprostane level was decreased by 75%. No significant difference was found in lymphocyte DNA damage. Fruit supplementation also decreased serum total cholesterol concentration. In conclusion, consumption of cherries and plums (10 servings/d) decreases oxidative stress by improving antioxidant status in healthy humans possibly due to high anthocyanin content in these fruits. (Cancer Prev Res 10, 60-66, 2005)

Keywords: Anthocyanin, Plum, Cherries, Oxidative stress, FRAP, DNA damage, α-tocopherol