Inhibitory effects of coffee on the genotoxicity of carcinogens in mice.

The mouse bone marrow micronucleus test was carried out to evaluate the possible inhibitory effects of 3 doses (125, 250 and 500 mg/kg) of standard instant coffee on the in vivo genotoxicity of 7,12-dimethylbenz[a]anthracene (DMBA), benzo[a]pyrene (BP), aflatoxin B1 (AFB1) and urethane (UR). Coffee was orally administered twice, 2 and 20 h before the carcinogens were injected intraperitoneally. From the results obtained, it was evident that the administration of 250 and 500 mg coffee/kg body weight could significantly inhibit the in vivo genotoxicity of these carcinogens. A linear dose response was observed for the inhibitory effect of coffee. Furthermore, inhibition of genotoxicity by coffee was observed in bone marrow cells which were sampled at 6-h intervals (48, 54, 60, 66 and 72 h) from the time of peak induction of micronuclei by DMBA.