Influence of dietary fatty acid, vegetable, and vitamin intake on etheno-DNA adducts in white blood cells of healthy female volunteers: A pilot study

Etheno-DNA adducts such as 1,N-6-ethenodeoxyadenosine (epsilon dA) and N-2, 3-ethenodeoxycytidine (epsilon dC) are formed as result of oxidative stress and lipid peroxidation via reactive alkenals (J. Nair et al., Mutat. Res., 424: 59-69, 1999). High <(<omega>)over bar>-6 polyunsaturated fatty acid i ntake markedly increased levels of WBCs in female volunteers on a controlle d diet (J. Nair et al., Cancer Epidemiol. Biomark. Prev., 6: 591-601, 1997) . In healthy female volunteers we investigated possible correlations betwee n dietary fatty acid intake (by questionnaire), concentration of linoleic a cid (LA) and oleic acid (OA) in serum (n = 34), and etheno-DNA adduct level s in WBC (n = 42). Two groups of samples were selected according to dietary intake > 15 g (group A) or <5 g (group B) LA/day. Serum samples were analy zed for free OA and LA by gas chromatography-mass spectroscopy and WBC-DNA for epsilon dA and epsilon dC adducts by immunoaffinity P-32 postlabeling. On a group level, serum LA and OA concentrations were higher in group A tha n group B, whereas the LA/OA ratios were similar. The mean epsilon dA and e psilon dC levels did not significantly differ in groups A and B, but a thir d of the individuals had more than twice the mean adduct levels than the re st. Correlation analyses revealed a significant inverse correlation for eps ilon dA in WBC-DNA and vegetable or vitamin E consumption. We conclude that etheno-DNA adduct levels are not determined by LA intake alone but might d epend on the ratio of <(<omega>)over bar>-6 polyunsaturated fatty acid:othe r fatty acids and of antioxidants consumed in the diet. This pilot study al so indicated a protective effect of dietary vitamin E and vegetables agains t miscoding, lipid peroxidation-induced DNA lesions.