These authors contributed equally to this work.
Vascular deconjugation of quercetin glucuronide: The flavonoid paradox revealed?
Article first published online: 7 OCT 2011
Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Molecular Nutrition & Food Research
Volume 55, Issue 12, pages 1780–1790, December 2011
How to Cite
Menendez, C., Dueñas, M., Galindo, P., González-Manzano, S., Jimenez, R., Moreno, L., Zarzuelo, M. J., Rodríguez-Gómez, I., Duarte, J., Santos-Buelga, C. and Perez-Vizcaino, F. (2011), Vascular deconjugation of quercetin glucuronide: The flavonoid paradox revealed?. Mol. Nutr. Food Res., 55: 1780–1790. doi: 10.1002/mnfr.201100378
- Issue published online: 2 DEC 2011
- Article first published online: 7 OCT 2011
- Manuscript Accepted: 9 AUG 2011
- Manuscript Revised: 27 JUL 2011
- Manuscript Received: 6 JUN 2011
- Spanish Ministerio de Ciencia e Innovación. Grant Numbers: AGL2007-66108, SAF2008-03948, AGL2009-12001, SAF2010-22066
- Consolider-Ingenio 2010 Programme. Grant Number: CSD2007-00063
- Junta de Andalucia (Proyecto de Excelencia. Grant Number: P06-CTS-01555
- Ministerio de Sanidad y Consumo, Instituto de Salud Carlos III. Grant Number: Red HERACLES RD06/0009
- Juan de la Cierva and Marie Curie
- Formación del Personal Investigador
- Blood pressure;
Scope: The dietary flavonoid quercetin exerts protective cardiovascular effects. Because quercetin is rapidly metabolized into less active or inactive glucuronidated metabolites and the plasma concentrations of free quercetin are very low, a huge amount of scientific data generated along decades with the unconjugated compounds in vitro has been questioned. We aimed to determine whether glucuronidated quercetin can deconjugate in situ and whether deconjugation leads to a biological effect.
Methods and results: Quercetin and quercetin-3-O-glucuronide (Q3GA) were perfused through the isolated rat mesenteric vascular bed. Quercetin was rapidly metabolized in the mesentery. In contrast, the decay of Q3GA was slower and was accompanied by a progressive increase of quercetin in the perfusate and in the tissue over 6 h, which was prevented by the β-glucuronidase inhibitor saccharolactone. Incubation of mesenteric arterial rings mounted in a wire myograph with Q3GA for ≥1 h resulted in a significant inhibition of the contractile response which was also prevented by saccharolactone. Moreover, the intravenous administration of Q3GA resulted in a slow onset and sustained blood pressure lowering effect, demonstrating for the first time that Q3GA has effects in vivo.
Conclusion: We propose that Q3GA behaves as a quercetin carrier in plasma, which deconjugates in situ releasing the aglycone which is the final effector.