BETA-CAROTENE PARTIALLY PREVENTS THE DAMAGE-INDUCED BY 1,4-DIMETHYLAMINOAZOBENZENE IN MICE

Hepatocarcinogenesis (HC) induced by various carcinogens such as 1,4-d imethylaminoazobenzene (DAB) is a multistep and complex process. The a nticancer efficacy of beta-carotene (beta C) was evaluated by estimati ng some biochemical parameters during the initiation stage of HC. beta C dietary supplementation partially prevented the rise in delta-amino levulinate synthetase activity. P 450 levels were dramatically enhance d in all groups studied. beta C administration did not overcome catala se inactivation due to DAB treatment; however, superoxide dismutase ac tivity levels showed to be less decreased in the DAB + beta C animals in comparison to the DAB group. The great enhancement provoked by DAB of glutathione S-transferase, a proposed marker of HC, was partially r eversed by beta C. In conclusion, heme pathway regulation, drug metabo lism, and natural oxidative defence systems, strikingly modified in DA B fed animals, were partially controlled by provitamin A. The potentia l use of beta C in preventing carcinogenesis is suggested, (C) 1998 Li ppincott Williams & Wilkins.