Chemopreventive properties of chlorophylls towards aflatoxin B1: a review of the antimutagenicity and anticarcinogenicity data in rainbow trout.
The anticarcinogenic activity of chlorophyllin (CHL), a water-soluble derivative of chlorophyll, was first reported in rainbow trout. This review describes certain experiments which set the stage for long-term tumor bioassays, in trout and other species, using CHL and various food-borne carcinogens. Initial work with trout and rat liver enzymes in the Salmonella assay showed that CHL was a potent antimutagen towards heterocyclic amines, polycyclic aromatic hydrocarbons, aflatoxins and other classes of mutagen. Antimutagenic activity was further demonstrated using the corresponding direct-acting mutagens in the absence of an exogenous metabolizing system. Mutagen-inhibitor interaction (molecular complex formation) was identified in spectrophotometry studies, suggesting that CHL acts as an 'interceptor molecule'. In vivo, CHL reduced hepatic AFB1-DNA adducts and hepatocarcinogenesis when the inhibitor and carcinogen were co-administered in the diet. Finally, co-injection of inhibitor and AFB1 into trout embryos established that CHL was more effective than chlorophyll a in reducing AFB1-DNA adducts 2 weeks after injection, and liver tumors after 1 year.
Department of Environmental Biochemistry, University of Hawaii, Honolulu 96822, USA.
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R
Dashwood
T
T
Negishi
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H
Hayatsu
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V
Breinholt
J
J
Hendricks
G
G
Bailey
D016604:Aflatoxin B1 / Q000037:antagonists & inhibitors*; D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D016587:Antimutagenic Agents / Q000494:pharmacology*; D002735:Chlorophyllides / Q000494:pharmacology*; D018736:DNA Adducts; D008114:Liver Neoplasms, Experimental / Q000517:prevention & control; D008958:Models, Molecular; D017686:Oncorhynchus mykiss / Q000196:embryology
D016588:Anticarcinogenic Agents; D016587:Antimutagenic Agents; D002735:Chlorophyllides; D018736:DNA Adducts; D016604:Aflatoxin B1; C007020:chlorophyllin