of crocin dyes in the acute hepatic damage induced by aflatoxin B1 and dimethyInitrosamine in rats. Carcinogenesis

Chemopreventive agents are compounds that inhibit carcino-genesis when administered prior or subsequent to a course of carcinogen administration. The effects of dietary admin-istration of crocin dyes on the hepatic damage induced by aflatoxin Bt (AFBt) and dimethylnitrosamine (DMN) in rats were investigated. Female Sprague-Dawley rats were treated with different dosages of A F ^ (0.9 or 4.5 mg/kg) or DMN (8 or 20 mg/kg) by i.p. administration, and the different degrees of hepatic damage were revealed by the elevations of levels of serum marker enzymes such as aspartate amino-transferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase and lactic dehydrogenase. Pre-treatment of the animals with crocin dyes 50 mg/kg dai-ly for three consecutive days, the enzyme elevations were significantly suppressed. This suggested that the crocin dyes possessed chemopreventive effects on the early acute hepatic damage induced by AFBj or DMN. Feeding experiments demonstrated that crocin dyes at 0.1 % in the diet could sup-press partially the chronic hepatic damage induced by multi-ple dosages of AFBj or DMN, but at a higher concentration of 1 % crocin dye failed to do so because of their host toxici-ty. Crocin dyes are extracted from the fruits of Gardenia jas-minoides and consist of carotenoids and geniposides as active principles. The protective mechanisms of crocin dyes may be attributed to their carotenoids which are converted meta-bolically to retinoids in rats