ANTIOXIDANT STATUS AND DIETARY-LIPID UNSATURATION MODULATE OXIDATIVE DNA-DAMAGE

High performance liquid chromatography with electrochemical detection (HPLC-EC) was used to measure 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker for oxidative DNA damage, in mammary gland isolated from tumor- bearing and tumor-free rats fed diets of varied fatty acid composition and vitamin E and selenium content. A method for tissue preparation a nd analysis is reported and a significant positive correlation shown b etween degree of unsaturation of dietary fatty acids and 8-OHdG concen tration, regardless of antioxidant status. The increase in 8-OHdG conc entration with greater fatty acid unsaturation was more pronounced in the absence of adequate dietary vitamin E and selenium. The implicatio ns of these data for defining the role of dietary lipid in the process of mammary carcinogenesis are discussed.