Induction of CYP1A by Green Tea Extract in Human Intestinal Cell Lines

Abstract

In this study the influence of green tea extract (GTE) or its component epigallocatechin gallate (EGCG) on the expression of different cytochrome P450 (CYP) isoenzymes was investigated in the human gastrointestinal epithelial cell lines LS-180 and Caco-2. Additionally, the effect of GTE or EGCG on functional activity of different CYP isoenzymes was investigated in vitro. mRNA expression levels were determined by quantitative RT-PCR and compared with protein levels. In LS-180 cells GTE, but not EGCG, significantly induced CYP1A2 mRNA expression, whereas neither CYP1A1 nor CYP3A4 mRNA expression was modulated by GTE or EGCG. In Caco-2 cells CYP1A1 as well as CYP1A2 mRNA expression was significantly increased in a dose-dependent manner by GTE and EGCG. However, EGCG alone was about 3 - 5-fold less effective than GTE. mRNA expression of CYP1A1 or CYP1A2 induced by the promutagen benzo[a]pyrene was significantly down-regulated by EGCG but not by GTE. CYP1A protein levels in response to GTE in Caco-2 and LS-180 cells confirmed the mRNA expression results. CYP activity was measured with CYP1A2 or CYP3A4 expressed in insect cell membranes using a luminescent method. GTE or EGCG significantly inhibited CYP1A2 and CYP3A4 function in a dose-dependent manner. Therefore, it appears that green tea moderately modulates the expression of drug-metabolizing enzymes but non-specifically inhibits the function of human CYPs. Since CYP enzymes play an important role in detoxification processes, these results might be of relevance for the prediction of the outcome of future clinical studies.

Green tea - Camellia sinensis (L.) O. Kuntze - Theaceae - cytochrome P450 1A - cytochrome P450 3A4

References

• 1 Kaminsky L S, Zhang Q Y. The small intestine as a xenobiotic-metabolizing organ.  Drug Metab Dispos. 2003;  31 1520-5
• 2 Borlak J, Zwadlo C. Expression of drug-metabolizing enzymes, nuclear transcription factors and ABC transporters in Caco-2 cells.  Xenobiotica. 2003;  33 927-43
• 3 Schmiedlin-Ren P, Thummel K E, Fisher J M, Paine M F, Lown K S, Watkins P B. Expression of enzymatically active CYP3A4 by Caco-2 cells grown on extracellular matrix-coated permeable supports in the presence of 1alpha,25-dihydroxyvitamin D3.  Mol Pharmacol. 1997;  51 741-54
• 4 Li W, Harper P A, Tang B K, Okey A B. Regulation of cytochrome P450 enzymes by aryl hydrocarbon receptor in human cells: CYP1A2 expression in the LS180 colon carcinoma cell line after treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin or 3-methylcholanthrene.  Biochem Pharmacol. 1998;  56 599-612
• 5 Schuetz E G, Beck W T, Schuetz J D. Modulators and substrates of P-glycoprotein and cytochrome P4503A co-ordinately up-regulate these proteins in human colon carcinoma cells.  Mol Pharmacol. 1996;  49 311-8
• 6 Hebert M F, Roberts J P, Prueksaritanont T, Benet L Z. Bioavailability of cyclosporine with concomitant rifampin administration is markedly less than predicted by hepatic enzyme induction.  Clin Pharmacol Ther. 1992;  52 453-7
• 7 Thummel K E, O'Shea D, Paine M F, Shen D D, Kunze K L, Perkins J D. et al . Oral first-pass elimination of midazolam involves both gastrointestinal and hepatic CYP3A-mediated metabolism.  Clin Pharmacol Ther. 1996;  59 491-502
• 8 McDonnell W M, Scheiman J M, Traber P G. Induction of cytochrome P450IA genes (CYP1A) by omeprazole in the human alimentary tract.  Gastroenterology. 1992;  103 1509-16
• 9 Lindell M, Karlsson M O, Lennernas H, Pahlman L, Lang M A. Variable expression of CYP and Pgp genes in the human small intestine.  Eur J Clin Invest. 2003;  33 493-9
• 10 Knize M G, Salmon C P, Pais P, Felton J S. Food heating and the formation of heterocyclic aromatic amine and polycyclic aromatic hydrocarbon mutagens/carcinogens.  Adv Exp Med Biol. 1999;  459 179-93
• 11 Gautier J C, Lecoeur S, Cosme J, Perret A, Urban P, Beaune P. et al . Contribution of human cytochrome P450 to benzo[a]pyrene and benzo[a]pyrene-7,8-dihydrodiol metabolism, as predicted from heterologous expression in yeast.  Pharmacogenetics. 1996;  6 489-99
• 12 Weisburger J H, Chung F L. Mechanisms of chronic disease causation by nutritional factors and tobacco products and their prevention by tea polyphenols.  Food Chem Toxicol. 2002;  40 1145-54
• 13 Katiyar S K, Agarwal R, Zaim M T, Mukhtar H. Protection against N-nitrosodiethylamine- and benzo[a]pyrene-induced forestomach and lung tumorigenesis in A/J mice by green tea.  Carcinogenesis. 1993;  14 849-55
• 14 Xu M, Bailey A C, Hernaez J F, Taoka C R, Schut H A, Dashwood R H. Protection by green tea, black tea, and indole-3-carbinol against 2-amino-3-methylimidazo[4,5-f]quinoline-induced DNA adducts and colonic aberrant crypts in the F344 rat.  Carcinogenesis. 1996;  17 1429-34
• 15 Pfrunder A, Gutmann H, Beglinger C, Drewe J. Gene expression of CYP3A4, ABC-transporters (MDR1 and MRP1-MRP5) and hPXR in three different human colon carcinoma cell lines.  J Pharm Pharmacol. 2003;  55 59-66
• 16 Netsch M I, Gutmann H, Luescher S, Brill S, Schmidlin C B, Kreuter M H. et al . Inhibitory activity of a green tea extract and some of its constituents on multidrug resistance-associated protein 2 functionality.  Planta Med. 2005;  71 135-41
• 17 Yang S P, Raner G M. Cytochrome P450 expression and activities in human tongue cells and their modulation by green tea extract.  Toxicol Appl Pharmacol. 2005;  202 140-50
• 18 Watkins P B. The barrier function of CYP3A4 and P-glycoprotein in the small bowel.  Adv Drug Deliv Rev. 1997;  27 161-70
• 19 Allen S W, Mueller L, Williams S N, Quattrochi L C, Raucy J. The use of a high-volume screening procedure to assess the effects of dietary flavonoids on human CYP1A1 expression.  Drug Metab Dispos. 2001;  29 1074-9
• 20 Williams S N, Shih H, Guenette D K, Brackney W, Denison M S, Pickwell G V. et al . Comparative studies on the effects of green tea extracts and individual tea catechins on human CYP1A gene expression.  Chem Biol Interact. 2000;  128 211-29
• 21 Whitlock J r. JP. Induction of cytochrome P4501A1.  Annu Rev Pharmacol Toxicol. 1999;  39 103-25
• 22 Taipalensuu J, Tornblom H, Lindberg G, Einarsson C, Sjöqvist F, Melhus H. et al . Correlation of gene expression of ten drug efflux proteins of the ATP-binding cassette transporter family in normal human jejunum and in human intestinal epithelial Caco-2 cell monolayers.  J Pharmacol Exp Ther. 2001;  299 164-70
• 23 Chen L, Bondoc F Y, Lee M J, Hussin A H, Thomas P E, Yang C S. Caffeine induces cytochrome P4501A2: induction of CYP1A2 by tea in rats.  Drug Metab Dispos. 1996;  24 529-33
• 24 Williams S N, Pickwell G V, Quattrochi L C. A Combination of tea (Camellia sinensis) catechins is required for optimal inhibition of induced CYP1A expression by green tea extract.  J Agric Food Chem. 2003;  51 6627-34
• 25 Maliakal P P, Coville P F, Wanwimolruk S. Tea consumption modulates hepatic drug metabolizing enzymes in Wistar rats.  J Pharm Pharmacol. 2001;  53 569-77
• 26 Nishikawa M, Ariyoshi N, Kotani A, Ishii I, Nakamura H, Nakasa H. et al . Effects of continuous ingestion of green tea or grape seed extracts on the pharmacokinetics of midazolam.  Drug Metab Pharmacokinet. 2004;  19 280-9
• 27 Muto S, Fujita K, Yamazaki Y, Kamataki T. Inhibition by green tea catechins of metabolic activation of procarcinogens by human cytochrome P450.  Mutat Res. 2001;  479 197-206
• 28 Hartter S, Nordmark A, Rose D M, Bertilsson L, Tybring G, Laine K. Effects of caffeine intake on the pharmacokinetics of melatonin, a probe drug for CYP1A2 activity.  Br J Clin Pharmacol. 2003;  56 679-82
• 29 Donovan J L, Chavin K D, Devane C L, Taylor R M, Wang J S, Ruan Y. et al . Green tea (Camellia sinensis) extract does not alter cytochrome P450 3A4 or 2D6 activity in healthy volunteers.  Drug Metab Dispos. 2004;  32 906-8