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Quercetin pharmacokinetics in humans.
Young J Moon1, Liang Wang, Robert DiCenzo
1Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, State University of New York, Amherst, NY 14260, USA.
Biopharmaceutics & Drug Disposition
|February 5, 2008
Summary
This study reveals quercetin
Area of Science:
- Pharmacology
- Pharmacokinetics
- Natural Products
Background:
- Quercetin, a common flavonoid, has demonstrated various biological activities.
- Understanding its absorption, distribution, metabolism, and excretion (ADME) is crucial for therapeutic applications.
- Enterohepatic recirculation can significantly influence drug bioavailability and efficacy.
Purpose of the Study:
- To investigate the pharmacokinetics of quercetin aglycone and its metabolites in humans.
- To develop a population pharmacokinetic model for quercetin that accounts for enterohepatic recirculation.
- To assess the stability and content of quercetin in a commercial herbal preparation.
Main Methods:
- High-performance liquid chromatography (HPLC) was used to determine quercetin stability and content.
- Blood and urine samples were collected from subjects receiving quercetin 500 mg three times daily.
- Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed to quantify quercetin and its metabolites.
- Noncompartmental analysis and population pharmacokinetic modeling (incorporating enterohepatic recirculation) were performed using WinNonlin.
Main Results:
- Quercetin exhibited high oral clearance (CL/F) of 3.5 x 10(4) L/h and an average terminal half-life of 3.5 hours.
- Plasma concentration-time curves showed characteristic re-entry peaks, indicative of enterohepatic recirculation.
- A one-compartment model incorporating enterohepatic recirculation provided the best fit for the observed plasma data.
Conclusions:
- This study provides the first comprehensive evaluation of quercetin pharmacokinetics and enterohepatic recirculation in humans.
- Population pharmacokinetic models adapted for enterohepatic recirculation are valuable for assessing its impact.
- The findings enhance our understanding of quercetin's behavior in the body, informing future research and clinical use.
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