title: Quercetin as a shuttle for labile iron.
abstract: The antioxidant activity of flavonoids may involve their ability to complex body iron in non-redox-active forms. In this study, it was found that the catechol flavonoids rutin and quercetin are able to suppress redox-active labile plasma iron (LPI) in both buffered solution and in iron-overloaded sera. Both flavonoids are effective in loading the metal into the iron-transport protein transferrin. Iron derivatives of quercetin and rutin are able to permeate cell membranes, however, only free quercetin is able to gain access to the cytosol and decrease intracellular labile iron pools. These results suggest that the antioxidant activity of quercetin may be dependent on its ability to shuttle labile iron from cell compartments followed by its transfer to transferrin.
authors.affiliation: Instituto de Química, Universidade de São Paulo. Av. Lineu Prestes 748-05508-000 São Paulo, Brazil.
authors.forename: Mayara Marinovic
authors.initials: MM
authors.lastname: Baccan
authors.forename: Orlando
authors.initials: O
authors.lastname: Chiarelli-Neto
authors.forename: Regina Mara Silva
authors.initials: RM
authors.lastname: Pereira
authors.forename: Breno Pannia
authors.initials: BP
authors.lastname: Espósito
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000737:chemistry; D001667:Binding, Competitive; D002417:Cattle; D056831:Coordination Complexes / Q000737:chemistry; D000077543:Deferiprone; D005296:Ferrous Compounds / Q000737:chemistry / Q000494:pharmacology; D005452:Fluoresceins / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D007501:Iron / Q000097:blood* / Q000737:chemistry; D007502:Iron Chelating Agents / Q000737:chemistry / Q000494:pharmacology*; D010084:Oxidation-Reduction; D011728:Pyridones / Q000737:chemistry / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000494:pharmacology; D011794:Quercetin / Q000737:chemistry / Q000494:pharmacology*; D012431:Rutin / Q000737:chemistry / Q000494:pharmacology; D014168:Transferrin / Q000737:chemistry
chemical_list: D000975:Antioxidants; D056831:Coordination Complexes; D005296:Ferrous Compounds; D005452:Fluoresceins; D007502:Iron Chelating Agents; D011728:Pyridones; D000644:Quaternary Ammonium Compounds; D014168:Transferrin; D000077543:Deferiprone; D012431:Rutin; D011794:Quercetin; C038178:ammonium ferrous sulfate; D007501:Iron; D001205:Ascorbic Acid; C007740:fluorexon