Plasma Profiling of Intact Isoflavone Metabolites by High-Performance Liquid Chromatography and Mass Spectrometric Identification of Flavone Glycosides Daidzin and Genistin in Human Plasma after Administration of Kinako
- 28 April 2008
- journal article
- Published by American Society for Pharmacology & Experimental Therapeutics (ASPET) in Drug Metabolism and Disposition
- Vol. 36 (8), 1485-1495
- https://doi.org/10.1124/dmd.108.021006
Abstract
The roles of isoflavones in the prevention of several hormone-dependent cancers and osteoporosis are of great interest. Despite many pharmacokinetics studies of the isoflavones, the actual types of conjugates circulating in the body and the position(s) of conjugation sites on the flavone skeleton are still uncertain because, in general, conjugated compounds in biological fluids have been evaluated by measuring the free aglycones obtained after selective enzymatic hydrolysis. Using an high-performance (HPLC)-UV-diode-array detector (DAD) method combined with solid-phase extraction, we have obtained HPLC profiles of isoflavone glycosides [daidzin (Din) and genistin (Gin)] and of intact isoflavone metabolites in human plasma: daidzein, genistein, daizein-7-glucuronide, daidzein-4′-glucuronide, genistein-7-glucuronide, genistein-4′-glucuronide, daidzein-7-sulfate, daidzein-4′-sulfate, genistein-7-sulfate, and genistein-4′-sulfate. We investigated the plasma profile of intact isoflavone metabolites in plasma obtained 1 to-7 h after orally administration of 50 g of kinako (baked soybean powder) to two healthy volunteers. The results of DAD analysis indicated that the main isoflavone metabolite peaks were identified on the HPLC chromatogram. Furthermore, the intact glycosides Din and Gin were detected in 1-h plasma samples by their positive electrospray ionization mass spectra, demonstrating that the glycosides Din and Gin can be absorbed from the gut.Keywords
This publication has 29 references indexed in Scilit:
- Molecular Effects of the Isoflavonoid Genistein in Prostate CancerClinical Prostate Cancer, 2005
- Soybean products and reduction of breast cancer risk: a case–control study in JapanBritish Journal of Cancer, 2005
- Metabolism of the soy isoflavones daidzein, genistein and glycitein in human subjects.: Identification of new metabolites having an intact isoflavonoid skeletonThe Journal of Steroid Biochemistry and Molecular Biology, 2003
- Measurement of intact sulfate and glucuronide phytoestrogen conjugates in human urine using isotope dilution liquid chromatography-tandem mass spectrometry with [13C3]isoflavone internal standardsAnalytical Biochemistry, 2002
- Phyto-oestrogens and cancerThe Lancet Oncology, 2002
- Characterization of Isoflavones and Their Conjugates in Female Rat Urine Using LC/MS/MSJournal of Agricultural and Food Chemistry, 2002
- Dietary flavonoid and isoflavone glycosides are hydrolysed by the lactase site of lactase phlorizin hydrolaseFEBS Letters, 2000
- Mass Spectrometric Identification and High-Performance Liquid Chromatographic Determination of a Flavonoid Glycoside Naringin in Human UrineJournal of Agricultural and Food Chemistry, 1999
- Lignan and isoflavonoid conjugates in human urineThe Journal of Steroid Biochemistry and Molecular Biology, 1995
- Plasma concentrations of phyto-oestrogens in Japanese menThe Lancet, 1993