| Green tea (Camellia sinensis) extract does not alter cytochrome p450 3A4 or 2D6 activity in healthy volunteers. | |
| | |
MedLine Citation:
|
PMID: 15319329 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Green tea extract is a widely used dietary supplement. The objective of this study was to assess the influence of a decaffeinated green tea (DGT; Camellia sinensis) extract on the activity of the drug-metabolizing enzymes cytochrome P-450 2D6 and 3A4. Probe drugs dextromethorphan (30 mg, CYP2D6 activity) and alprazolam (ALPZ; 2 mg, CYP3A4 activity) were administered orally to healthy volunteers (n = 11) at baseline, and again after treatment with four DGT capsules/day for 14 days. Each DGT capsule contained 211 +/- 25 mg of green tea catechins and <1 mg of caffeine. Dextromethorphan metabolic ratios (DMRs) and alprazolam pharmacokinetics were determined at baseline and after DGT treatment. There were no significant differences in ALPZ pharmacokinetics at baseline and after DGT treatment (all P values >/= 0.05; maximum concentration in plasma, 33 +/- 8 versus 34 +/- 13 ng/ml; time to reach maximum concentration in plasma, 1.4 +/- 1.2 versus 1.4 +/- 1.2 h; area under the plasma concentration versus time curve, 480 +/- 119 versus 510 +/- 107 h. ng. ml(-1); half-life of elimination, 12.3 +/- 1.7 versus 13.1 +/- 3.4 h). The DMR was 0.053 +/- 0.045 at baseline and 0.041 +/- 0.032 after DGT supplementation (P > 0.05). The plasma concentration of the green tea flavonoid, (-)-epigallocatechin gallate, reached 1.3 +/- 1.8 microM 2 h after DGT treatment. Our results indicate that DGT is unlikely to alter the disposition of medications primarily dependent on the CYP2D6 or CYP3A4 pathways of metabolism. |
| | |
Authors:
|
Jennifer L Donovan; Kenneth D Chavin; C Lindsay Devane; Robin M Taylor; Jun-Sheng Wang; Ying Ruan; John S Markowitz |
Related Documents
:
|
15337259 - Treatment with subthreshold doses of caffeine plus trihexyphenidyl fully restores locom... 7323439 - Metabolism of theophylline to caffeine in adults. 1273209 - Sensory, perceptual, motor and cognitive functioning and subjective reports following o... 16349909 - Adenosine triphosphate content of selenastrum capricornutum. 8390689 - Effects of s-2-(3-methylaminopropylamino)ethyl phosphorothioic acid (wr-3689), alone or... 3199059 - Increases in plasma concentrations of steroids in the rat after the administration of c... 9462549 - Antidiuretic effect of desmopressin given in hemostatic dosages to healthy volunteers. 17728109 - Nitric oxide involvement in the antidepressant-like effects of acute lithium administra... 1287969 - The immune response of sheep to subclinical chronic exposure to the herbicide bentazon tp. |
Publication Detail:
|
Type: Comparative Study; Journal Article; Research Support, N.I.H., Extramural; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
|
Title: Drug metabolism and disposition: the biological fate of chemicals Volume: 32 ISSN: 0090-9556 ISO Abbreviation: Drug Metab. Dispos. Publication Date: 2004 Sep |
Date Detail:
|
Created Date: 2004-08-20 Completed Date: 2005-06-23 Revised Date: 2008-11-21 |
Medline Journal Info:
|
Nlm Unique ID: 9421550 Medline TA: Drug Metab Dispos Country: United States |
Other Details:
|
Languages: eng Pagination: 906-8 Citation Subset: IM |
Affiliation:
|
Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston 29425, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Administration, Oral Adult Alprazolam / administration & dosage, blood, pharmacokinetics Camellia sinensis / chemistry* Capsules Catechin / analogs & derivatives*, blood, chemistry, pharmacology* Cytochrome P-450 CYP2D6 / physiology* Cytochrome P-450 CYP3A Cytochrome P-450 Enzyme System / physiology* Dextromethorphan / administration & dosage, blood, pharmacokinetics Dietary Supplements / analysis Drug Administration Schedule Female Half-Life Humans Male Plant Extracts / chemistry, metabolism, pharmacology* Plant Leaves / chemistry Time Factors |
| Grant Support | |
ID/Acronym/Agency:
|
M01 RR01070-18/RR/NCRR NIH HHS; R21 AT00511/AT/NCCAM NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Capsules; 0/Plant Extracts; 125-71-3/Dextromethorphan; 154-23-4/Catechin; 28981-97-7/Alprazolam; 9035-51-2/Cytochrome P-450 Enzyme System; 989-51-5/epigallocatechin gallate; EC 1.14.13.67/CYP3A4 protein, human; EC 1.14.14.1/CYP3A protein, human; EC 1.14.14.1/Cytochrome P-450 CYP2D6; EC 1.14.14.1/Cytochrome P-450 CYP3A |
| Comments/Corrections | |
Erratum In:
|
Drug Metab Dispos. 2004 Nov;32(11):1331 |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Altered pharmacokinetics of omeprazole in cystic fibrosis knockout mice relative to wild-type mice.
Next Document: Differences in the pharmacokinetics of peroxisome proliferator-activated receptor agonists in geneti...