Garlic powder and Allyl sulfur compounds enhance the ability of dietary selenite to inhibit 7,12‐dimethylbenz[a]anthracene‐induced mammary DNA adducts

Abstract

These studies examined the ability of garlic powder or allyl sulfur compounds to modify selenite protection against 7,12‐dimethylbenz[a] anthracene (DMBA)‐induced mammary epithelial cell DNA adducts. In Study 1, female rats (n = 5) were fed diets containing sodium selenite at 0.1, 0.5, or 1.0 mg Selkg and garlic powder at 0, 20, or 40 g/kg diet. Total DNA adducts correlated inversely with selenite or garlic powder intake. Garlic powder enhanced the selenite inhibition of mammary DNA adducts. In Study 2, selenite (2.0 mg Selkg diet), garlic powder (20 glkg diet), water‐soluble S‐allyl cysteine (SAC; 5.2 μmol/kg diet), and oil‐soluble diallyl disulfide (DADS; 5.2 μmol/kg diet) inhibited (p < 0.05) total DNA adducts by 45%, 40%, 80%, and 75%, respectively. Combining selenite with garlic powder, SAC, or DADS further inhibited DNA adducts. Selenite, but not garlic powder, SAC, or DADS, enhanced liver glutathione Stransferase and undine diphosphate‐glucurono‐syltransferase activities. Selenite, garlic powder, SAC, or DADS did not affect liver cytochrome P ‐450 1A1 activities. The present studies provide evidence that synergistic protection against the initiation of DMBA carcinogenesis occurs when selenite is supplemented in conjunction with garlic or its allyl sulfur components.