Glucuronides of tea catechins: enzymology of biosynthesis and biological activities
- PMID: 12642472
- DOI: 10.1124/dmd.31.4.452
Glucuronides of tea catechins: enzymology of biosynthesis and biological activities
Abstract
(-)-Epigallocatechin gallate (EGCG) and (-)-epigallocatechin (EGC) are major green tea catechins with antioxidant and anticancer activities. In this study, we characterized the glucuronidation of EGCG and EGC in human, mouse, and rat microsomes and by nine different human UGT 1A and 2B isozymes expressed in insect cells. Six EGCG and EGC glucuronides were biosynthesized, and their structures were identified for the first time. (-)-EGCG-4"-O-glucuronide was the major EGCG glucuronide formed in all incubations. The catalytic efficiency (V(max)/K(m)) for (-)-EGCG-4"-O-glucuronide formation followed the order: mouse intestine > mouse liver > human liver > rat liver >> rat small intestine. The UGT-catalyzed glucuronidation of EGC was much lower than that of EGCG. The V(max)/K(m) for (-)-EGC-3'-O-glucuronide followed the following order: mouse liver > human liver > rat liver > rat and mouse small intestine. Human UGT1A1, 1A8, and 1A9 had high activities with EGCG. UGT1A8, an intestine-specific UGT, had the highest V(max)/K(m) for EGCG but low activity with EGC. Mice appeared to be more similar to humans than rats to humans in the glucuronidation of EGCG and EGC. Some of these catechin glucuronides retained the activities of their parent compounds in radical scavenging and in inhibiting the release of arachidonic acid from HT-29 human colon cancer cells. These results provide foundations for understanding the biotransformation and biological activities of tea catechins.
Similar articles
-
Green Tea Suppresses Brain Aging.Molecules. 2021 Aug 12;26(16):4897. doi: 10.3390/molecules26164897. Molecules. 2021. PMID: 34443485 Free PMC article. Review.
-
Metabolism of green tea catechins: an overview.Curr Drug Metab. 2006 Oct;7(7):755-809. doi: 10.2174/138920006778520552. Curr Drug Metab. 2006. PMID: 17073579 Review.
-
Glucuronidation of the green tea catechins, (-)-epigallocatechin-3-gallate and (-)-epicatechin-3-gallate, by rat hepatic and intestinal microsomes.Free Radic Res. 2004 Sep;38(9):1025-31. doi: 10.1080/10715760410001728424. Free Radic Res. 2004. PMID: 15621722
-
Enzymology of methylation of tea catechins and inhibition of catechol-O-methyltransferase by (-)-epigallocatechin gallate.Drug Metab Dispos. 2003 May;31(5):572-9. doi: 10.1124/dmd.31.5.572. Drug Metab Dispos. 2003. PMID: 12695345
-
Glucuronidation and sulfation of the tea flavonoid (-)-epicatechin by the human and rat enzymes.Drug Metab Dispos. 2002 Aug;30(8):897-903. doi: 10.1124/dmd.30.8.897. Drug Metab Dispos. 2002. PMID: 12124307
Cited by
-
Combination of tea catechins and ornithine effectively activates the urea cycle: an in vitro and human pilot study.Eur J Appl Physiol. 2024 Mar;124(3):827-836. doi: 10.1007/s00421-023-05310-4. Epub 2023 Sep 14. Eur J Appl Physiol. 2024. PMID: 37707596
-
Co-consuming green tea with raloxifene decreases raloxifene systemic exposure in healthy adult participants.Clin Transl Sci. 2023 Oct;16(10):1779-1790. doi: 10.1111/cts.13578. Epub 2023 Aug 28. Clin Transl Sci. 2023. PMID: 37639334 Free PMC article.
-
Recent progress in DNA methyltransferase inhibitors as anticancer agents.Front Pharmacol. 2022 Dec 16;13:1072651. doi: 10.3389/fphar.2022.1072651. eCollection 2022. Front Pharmacol. 2022. PMID: 37077808 Free PMC article. Review.
-
Catechin Bioavailability Following Consumption of a Green Tea Extract Confection Is Reduced in Obese Persons without Affecting Gut Microbial-Derived Valerolactones.Antioxidants (Basel). 2022 Dec 18;11(12):2490. doi: 10.3390/antiox11122490. Antioxidants (Basel). 2022. PMID: 36552698 Free PMC article.
-
The Effects of Antioxidant Nutraceuticals on Cellular Sulfur Metabolism and Signaling.Antioxid Redox Signal. 2023 Jan;38(1-3):68-94. doi: 10.1089/ars.2022.0077. Epub 2022 Dec 20. Antioxid Redox Signal. 2023. PMID: 35819295 Free PMC article. Review.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources