title: Transport of genistein-7-glucoside by human intestinal CACO-2 cells: potential role for MRP2.
abstract: This study demonstrated rapid apical to basolateral absorption of genistein across Caco-2 cell monolayers with a P(app) of 20.0+/-0.8 x 10(-6)cm/sec. In contrast, genistein's main dietary source, genistein-7-glucoside (genistin), was not absorbed. In fact, genistin demonstrated basolateral to apical efflux of 1.28+/-0.10 x 10(-6) cm/sec, which exceeded the flux of the paracellular transport marker mannitol by 6-fold. Although genistin hydrolysis to genistein occurred in the preparation, it did not contribute significantly to these observations. In experiments trying to define the efflux mechanism for genistin, MK-571 reduced the efflux by 87% to 0.19+/-0.02 x 10(-6) cm/sec, implying transport by the polarized efflux pump MRP2.
authors.affiliation: Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston 29425, USA.
authors.forename: U K
authors.initials: UK
authors.lastname: Walle
authors.forename: K L
authors.initials: KL
authors.lastname: French
authors.forename: R A
authors.initials: RA
authors.lastname: Walgren
authors.forename: T
authors.initials: T
authors.lastname: Walle
mesh_terms: D027321:Anion Transport Proteins; D001692:Biological Transport; D018938:Caco-2 Cells; D002352:Carrier Proteins / Q000378:metabolism*; D019008:Drug Resistance, Neoplasm; D019833:Genistein / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007413:Intestinal Mucosa / Q000378:metabolism; D007529:Isoflavones / Q000378:metabolism*
chemical_list: D027321:Anion Transport Proteins; D002352:Carrier Proteins; D007529:Isoflavones; C040641:genistin; D019833:Genistein