title: Retinol (vitamin A) as an inhibitor of the mutagenicity of aflatoxin B.
abstract: Vitamin A (retinol) was shown to inhibit the mutagenic activity of aflatoxin B1 (AFB1), when added to the Ames Salmonella/mammalian microsome assay. The inhibition was dose-dependent and not caused by a direct toxic effect on the test bacteria. On the other hand the mutagenicity of diepoxybutane, a mutagen not requiring metabolic activation, was not affected by retinol, indicating that the vitamin does not act as a general scavenger of reactive compounds. The mutagenicity of AFB1 depends on the balance between formation and breakdown of aflatoxin 2,3-epoxide, the presumed ultimate mutagenic/carcinogenic metabolite. Inhibition of AFB1 mutagenicity could thus result from decreased formation or increased breakdown of the 2,3-epoxide.
mesh_terms: D000348:Aflatoxins / Q000037:antagonists & inhibitors*; D000818:Animals; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008297:Male; D009153:Mutagens / Q000037:antagonists & inhibitors*; D051381:Rats; D012486:Salmonella typhimurium / Q000235:genetics; D014801:Vitamin A / Q000494:pharmacology*
chemical_list: D000348:Aflatoxins; D009153:Mutagens; D014801:Vitamin A