title: Metabolism of galangin by rat cytochromes P450: relevance to the genotoxicity of galangin.
abstract: The mutagenicity of flavonols seems to depend on the number and position of hydroxyl groups in the B ring. Galangin is a flavonol that does not have any hydroxyl group in the B ring and has been suggested to be a substrate of cytochromes P450 which, through the hydroxylation of the B ring, could metabolise it to more genotoxic products. The present study was undertaken to test this hypothesis. Using high performance liquid chromatography we show that glangin is sequentially transformed to kaempferol and then to quercetin by a mechanism dependent on cytochrome P450 reactions. The metabolites of galangin are responsible for its mutagenicity in Salmonella typhimurium reversion assay and for the induction of chromosomal aberrations in V79 cells.
authors.affiliation: Department of Genetics, Faculty of Medical Sciences, New University of Lisbon, Portugal.
authors.forename: I D
authors.initials: ID
authors.lastname: Silva
authors.forename: A S
authors.initials: AS
authors.lastname: Rodrigues
authors.forename: J
authors.initials: J
authors.lastname: Gaspar
authors.forename: A
authors.initials: A
authors.lastname: Laires
authors.forename: J
authors.initials: J
authors.lastname: Rueff
mesh_terms: D000818:Animals; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002869:Chromosome Aberrations; D006224:Cricetinae; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005419:Flavonoids / Q000378:metabolism* / Q000633:toxicity; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D009153:Mutagens / Q000378:metabolism* / Q000633:toxicity; D051381:Rats; D017208:Rats, Wistar; D012486:Salmonella typhimurium / Q000378:metabolism
chemical_list: D005419:Flavonoids; D009153:Mutagens; C037032:galangin; D003577:Cytochrome P-450 Enzyme System