Caffeine inhibits hepatic-microsomal activation of some dietary genotoxins.
Hepatic microsomal fractions (microsomes) were prepared from female BALB/c mice. The potential of caffeine to modify the ability of microsomes to convert the heterocyclic aromatic amines MeIQ, Trp-P-2 and MeIQx, to bacterial mutagens (indicator: Salmonella typhimurium TA98) was investigated. Caffeine inhibited mutagenicity and did so by inhibiting microsomal metabolism of the three compounds, rather than by altering uptake of the active mutagens and/or interacting with the DNA repair processes in the bacterial cell. Notional Ki values determined for the three heterocyclic amines were similar, suggesting that caffeine inhibits at a stage common to the metabolism of all three compounds.
Alldrick
A J
AJ
Department of Microbiology, British Industrial Biological Research Association, Carshalton, Surrey, UK.
Rowland
I R
IR
D000818:Animals; D001711:Biotransformation; D002110:Caffeine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D009152:Mutagenicity Tests; D009153:Mutagens / Q000378:metabolism* / Q000494:pharmacology; D012016:Reference Values; D012486:Salmonella typhimurium / Q000187:drug effects
D009153:Mutagens; D002110:Caffeine