Dietary caffeine reduces the genotoxicity of MeIQx in the host‐mediated assay in mice
- 1 January 1995
- journal article
- other
- Published by Taylor & Francis in Nutrition and Cancer
- Vol. 24 (2), 143-150
- https://doi.org/10.1080/01635589509514402
Abstract
The influence of dietary caffeine on the genotoxicity of the cooked food mutagen 2‐amino‐3,8‐dimethylimidazo[4,5‐f]‐quinoxaline (MelQx) was evaluated using the host‐mediated assay in mice. For four weeks, BALBIc mice were fed a purified diet with or without caffeine (0.01% wt/wt in the diet). In the host‐mediated assay, Salmonella typhimurium TA98 was given intravenously immediately before an oral dose of MelQx (1.5 mglkg body wt). After one hour, the mice were killed, the Salmonellae were recovered from the liver, and the number of mutants (his+ revertants) were determined. Consumption of caffeine led to a 47% reduction in the number of mutants induced by MelQx (p < 0.001). Subsequent in vitro experiments using S. typhimurium TA98 revealed that the capacity of hepatic S‐9 fractions from the caffeine‐fed mice to covert MelQx to an active mutagen was reduced by approximately 35%. This effect was not attributable to caffeine in the S‐9 preparation. These data suggest that consumption of caffeine modifies MelQx mutagenicity by altering the spectrum of enzymes involved in its activation.Keywords
This publication has 23 references indexed in Scilit:
- Carcinogenic factors in food with relevance to colon cancer developmentMutation Research, 1993
- Cooking procedures and food mutagens: A literature reviewFood and Chemical Toxicology, 1993
- Modification of in vivo heterocyclic amine genotoxicity by dietary flavonoidsMutagenesis, 1989
- Covalent binding of [2-14C]2-amino-3,8-dimethylimidazo[4,5-f]-quinoxaline (MeIQx) to mouse DNA in vivoCarcinogenesis: Integrative Cancer Research, 1989
- Effect of dietary fibre on the mutagenicity and distribution of 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ)Mutation Research, 1989
- Metabolic activation of a protein pyrolysate promutagen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline by rat liver microsomes and purified cytochrome P-450Carcinogenesis: Integrative Cancer Research, 1988
- Carcinogenicity in rats of a mutagenic compound, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxalineCarcinogenesis: Integrative Cancer Research, 1988
- Carcinogenicity in mice of a mutagenic compound, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) from cooked foodsCarcinogenesis: Integrative Cancer Research, 1987
- Identification of the Mutagens in Cooked BeefEnvironmental Health Perspectives, 1986
- STRUCTURE OF A POTENT MUTAGEN ISOLATED FROM FRIED BEEFChemistry Letters, 1981