Effect in vitro of arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid on the hepatic activation of dietary genotoxins by rat post-mitochondrial fractions

Abstract

The effect of arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid on the conversion of the heterocyclic amine 2-amino-3-methylimidazo[4,5-ƒ]quinoline (IQ) to its genotoxic metabolites was investigated using a modified bacterial mutation assay. The assay used Salmonella typhimurium TA98 as an indicator of the mutagenicity and hepatic post-mitochondrial fractions (S-9) from male Sprague-Dawley rats as the activating system. All three fatty acids inhibited the mutagenicity of IQ without effect on the uptake of the active metabolites and/or on the DNA repair processes within the bacterial cell. The activation of three other food mutagens, 2-amino-3,8-dimethylimidazo[4,5-ƒ]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP) and aflatoxin B 1 (AFB 1) was also inhibited by these fatty acids.