ArticleBioMed research international2014
Quercetin significantly inhibits the metabolism of caffeine, a substrate of cytochrome P450 1A2 unrelated to CYP1A2*1C (-2964G>A) and *1F (734C>A) gene polymorphisms.
Article in BioMed research international, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.
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Who cites it
7 citing papers in PubMed, 12 citations in OpenAlex.
- Beyond Antibiotics: Traditional Chinese Medicine and Flavonoids in the Management of Endometritis.Veterinary sciences · 2026Review
- Tuning the Pharmacokinetic Performance of Quercetin by Cocrystallization.Crystal growth & design · 2023Article
- Article
- Enzyme Activity of Natural Products on Cytochrome P450.Molecules (Basel, Switzerland) · 2022Review
- Assessment of Metabolic Interaction between Repaglinide and Quercetin via Mixed Inhibition in the Liver: In Vitro and In Vivo.Pharmaceutics · 2021Article
- Novel insights on caffeine supplementation, CYP1A2 genotype, physiological responses and exercise performance.European journal of applied physiology · 2021Review
- Effect of Naringenin, Quercetin, and Sesamin on Xenobiotica-Metabolizing CYP1A and CYP3A in Mice Offspring after Maternal Exposure to Persistent Organic Pollutants.BioMed research international · 2017Article
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Authors and funding
8 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundQuercetin is abundant in plants and human diets. Previous studies indicated that quercetin inhibited the activity of CYP1A2, and the combination of quercetin with the substrates of CYP1A2 might produce herb-drug interactions. This research aims to determine the effects of quercetin and the CYP1A2 gene polymorphisms, namely, CYP1A2*1C (-2964G>A) and *1F (734C>A), on the metabolism of caffeine.
methodThe experiment was designed into two treatment phases separated by a 2-week washout period. Six homozygous individuals for the CYP1A2*1C/*1F (GG/AA) genotype and 6 heterozygous individuals for the CYP1A2*1C/*1F (GA/CA) genotype were enrolled in the study. Quercetin capsules (500 mg) were given to each volunteer once daily for 13 consecutive days, and after that, each subject was coadministrated 100 mg caffeine capsules with 500 mg quercetin on the 14th day. Then a series of venous blood samples were collected for HPLC analysis. Correlation was determined between pharmacokinetics of caffeine and paraxanthine with caffeine metabolite ratio.
resultsQuercetin significantly affected the pharmacokinetics of caffeine and its main metabolite paraxanthine, while no differences were found in the pharmacokinetics of caffeine and paraxanthine between GG/AA and GA/CA genotype groups.
conclusionQuercetin significantly inhibits the caffeine metabolism, which is unrelated to CYP1A2*1C (-2964G>A) and *1F (734C>A) gene polymorphisms.
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