Oxidative DNA damage: Induction by fructose, in vitro, and its enhancement by hydrogen peroxide

Sucrose and high-fructose corn syrup comprise nearly equal amounts of glucose and fructose. With the use of high-fructose corn syrup in the food industry, consumption of fructose, which may be a tumor promoter, has increased dramatically. We examined fructose-induced oxidative DNA damage in the presence of Cu(II), with or without the addition of H₂O₂. With isolated DNA, fructose induced Cu(II)-mediated DNA damage, including formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), to a greater extent than did glucose, and H₂O₂ enhanced the damage. In cultured human cells, 8-oxodG formation increased significantly following treatment with fructose and the H₂O₂-generating enzyme glucose oxidase. Fructose may play an important role in oxidative DNA damage, suggesting a possible mechanism for involvement of fructose in carcinogenesis.