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Cited by 400Tea Polyphenols and EffectsPhytochemicals and Antioxidant ActivitiesDrug Solubulity and Delivery Systems

The DOI matches its Crossref record; 31 of the 31 references it cites were found in a registry or an index.

Effects of Dosing Condition on the Oral Bioavailability of Green Tea Catechins after Single-Dose Administration of Polyphenon E in Healthy Individuals

Chow, H-H. Sherry, Hakim, Iman A., Vining, Donna R., Crowell, James A., Ranger-Moore, James, Chew, Wade M., Celaya, Catherine A., Rodney, Steven R., Hara, Yukihiko, Alberts, David S.·2005·Clinical Cancer Research
DOI 10.1158/1078-0432.ccr-04-2549
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Abstract

Purpose: Green tea has been shown to exhibit cancer-preventive activities in preclinical studies. Its consumption has been associated with decreased risk of certain types of cancers in humans. The oral bioavailability of the major green tea constituents, green tea catechins, is low, resulting in systemic catechin levels in humans many fold less than the effective concentrations determined in in vitro systems. We conducted this clinical study to test the hypothesis that the oral bioavailability of green tea catechins can be enhanced when consumed in the absence of food. Experimental Designs: Thirty healthy volunteers were randomly assigned to one of the following doses of Polyphenon E (a decaffeinated and defined green tea catechin mixture): 400, 800, or 1,200 mg, based on the epigallocatechin gallate content (10 subjects per dose group). After an overnight fast, study participants took a single dose of Polyphenon E with or without a light breakfast, which consisted of one or two 4-oz muffins and a glass of water. Following a 1-week wash-out period, subjects were crossed over to take the same dose of Polyphenon E under the opposite fasting/fed condition. Tea catechin concentrations in plasma and urine samples collected after dosing were determined by high-pressure liquid chromatography analysis. Results: Consistent with previous reports, epigallocatechin gallate and epicatechin gallate were present in plasma mostly as the free form, whereas epicatechin and epigallocatechin were mostly present as the glucuronide and sulfate conjugates. There was >3.5-fold increase in the average maximum plasma concentration of free epigallocatechin gallate when Polyphenon E was taken in the fasting condition than when taken with food. The dosing condition led to a similar change in plasma-free epigallocatechin and epicatechin gallate levels. Taking Polyphenon E in the fasting state did not have a significant effect on the plasma levels of total (free and conjugated) epigallocatechin, but resulted in lower plasma levels of total epicatechin. Urinary epigallocatechin gallate and epicatechin gallate levels were very low or undetectable following Polyphenon E administration with either dosing condition. Taking Polyphenon E under the fasting state resulted in a significant decrease in the urinary recovery of total epigallocatechin and epicatechin. Polyphenon E administered as a single dose over the dose range studied was generally well-tolerated by the study participants. Mild and transient nausea was noted in some of the study participants and was seen most often at the highest study agent dose (1,200 mg epigallocatechin gallate) and in the fasting condition. Conclusions: We conclude that greater oral bioavailability of free catechins can be achieved by taking the Polyphenon E capsules on an empty stomach after an overnight fast. Polyphenon E up to a dose that contains 800 mg epigallocatechin gallate is well-tolerated when taken under the fasting condition. This dosing condition is also expected to optimize the biological effects of tea catechins.

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Crossref · 10.1158/1078-0432.ccr-04-2549

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Research works printed but not linked: 1

  1. Hong J, Smith TJ, Ho CT, August D, Yang CS. Effects of purified green and black tea polyphenols on cyclooxygenase- and lipoxygenase-dependent metabolism of arachidonic acid in human colon mucosa and colon tumor tissues. Biochem Pharmacol 2001;62:1175–83.

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Metadata

Authors
Chow, H.-H. S., Hakim, I. A., Vining, D. R., Crowell, J. A., Ranger-Moore, J., Chew, W. M., Celaya, C. A., Rodney, S. R., Hara, Y., & Alberts, D. S.
Affiliations
  • University of Arizona (US)
  • National Cancer Institute (US)
  • 1Arizona Cancer Center, The University of Arizona, Tucson, Arizona;
  • 3Mitsui Norin Co., Ltd., Shizuoka, Japan
ORCID
Venue
Clinical Cancer Research
Publisher
American Association for Cancer Research (AACR)
Published
2005-06-15
Volume
11
Issue
12
Pages
4627-4633
ISSN
  • 1078-0432 (ISSN-L)
  • 1557-3265
DOI
10.1158/1078-0432.ccr-04-2549
OpenAlex
W2152835156
Cited by
400
References
31
Citations by year
2026: 10 · 2025: 13 · 2024: 9 · 2023: 15 · 2022: 13 · 2021: 21 · 2020: 10 · 2019: 10 · 2018: 18 · 2017: 17 · 2016: 29 · 2015: 26 · 2014: 21 · 2013: 29 · 2012: 34
FWCI
8.80
Type
journal article
Language
en
Open access
closed
Locations
  • Clinical Cancer Research (publishedVersion)
  • PubMed (publishedVersion)
Funders
National Cancer Institute (N01-CN-25119)
Topics
  • Life Sciences › Agricultural and Biological Sciences › Food Science › Tea Polyphenols and Effects
  • Health Sciences › Medicine › Biochemistry (medical) › Phytochemicals and Antioxidant Activities
  • Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Pharmaceutical Science › Drug Solubulity and Delivery Systems
Keywords
green tea catechins, oral bioavailability, Polyphenon E, epigallocatechin gallate, epicatechin gallate, epigallocatechin, epicatechin, fed versus fasted state, food effect, urinary excretion, dose proportionality, single-dose administration, healthy volunteers, cancer prevention
MeSH terms
Administration, Oral, Adult, Aged, Biological Availability, Catechin, Chromatography, High Pressure Liquid, Dose-Response Relationship, Drug, Female, Flavonoids, Headache, Humans, Male, Metabolic Clearance Rate, Middle Aged, Nausea, Tea, Abdominal Pain, Cross-Over Studies, Area Under Curve

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