Population nutrikinetics of green tea extract

Scholl, Catharina; Lepper, Anna; Lehr, Thorsten; Hanke, Nina; Schneider, Katharina; Brockmöller, Jürgen; Seufferlein, Thomas; Stingl, Julia C.

doi:10.1371/journal.pone.0193074

Cited by 55 publications

(38 citation statements)

References 47 publications

(72 reference statements)

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“…A recent study suggested that P-gp could involve the absorption and elimination of green tea [ 30 ], and in the current study, repeated dosing of the catechins appeared to reduce the T 1/2 of ECG and EC. Large inter-individual variabilities for PK parameters were observed, and the degree of exposure to the body varied greatly with each catechin, which would be expected due to the differences in absorption and drug transport between individuals.…”

Section: Resultssupporting

confidence: 68%

Quantitative Analysis of Four Catechins from Green Tea Extract in Human Plasma Using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry for Pharmacokinetic Studies

2018

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Green tea is consumed as a beverage worldwide and has beneficial effects, such as a lower risk of cardiovascular disease and cancer. A quantitative analysis of the beneficial components in plasma is important for understanding the potential health benefits of green tea. Four catechins—epigallocatechin-3-gallate (EGCG), epicatechin-3-gallate (ECG), epigallocatechin (EGC), and epicatechin (EC)—which account for the majority of the components of green tea, were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In this study, a validated method was optimized to obtain the blood concentrations after the one-time ingestion of 630 mg green tea extract with digoxin and then after the ingestion of 630 mg green tea repeatedly for 15 days. The calibration curve, including the LLOQ, was constructed over 1–500 ng/mL for EGCG, ECG, and EGC and 0.1–50 ng/mL for EC. The method for inter- and intra-validation was applied, acceptable for both accuracy and precision. We successfully developed an appropriate UPLC-MS/MS method for human plasma with good reproducibility and sensitivity. Thus, this method could be applied for future preclinical and clinical studies on EGCG, ECG, EGC, and EC.

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Section: Resultssupporting

confidence: 68%

Quantitative Analysis of Four Catechins from Green Tea Extract in Human Plasma Using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry for Pharmacokinetic Studies

2018

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“…Furthermore, the same study group showed that methylenetetrahydrofolate reductase and thymidylate synthase genotypes affected the association between green tea consumption and breast cancer risk [ 24 ]. In recent years, several studies on various malignancies have shown the relationship between the anticancer effects of GTPs and genetic polymorphisms [ 96 , 97 ]. With regard to bladder cancer, a study reported that genotype was significantly associated with tea consumption-associated changes in bladder cancer risk [ 47 ].…”

Section: Bladder Cancer and Green Teamentioning

confidence: 99%

Anticancer Effects of Green Tea and the Underlying Molecular Mechanisms in Bladder Cancer

et al. 2018

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Green tea and green tea polyphenols (GTPs) are reported to inhibit carcinogenesis and malignant behavior in several diseases. Various in vivo and in vitro studies have shown that GTPs suppress the incidence and development of bladder cancer. However, at present, opinions concerning the anticancer effects and preventive role of green tea are conflicting. In addition, the detailed molecular mechanisms underlying the anticancer effects of green tea in bladder cancer remain unclear, as these effects are regulated by several cancer-related factors. A detailed understanding of the pathological roles and regulatory mechanisms at the molecular level is necessary for advancing treatment strategies based on green tea consumption for patients with bladder cancer. In this review, we discuss the anticancer effects of GTPs on the basis of data presented in in vitro studies in bladder cancer cell lines and in vivo studies using animal models, as well as new treatment strategies for patients with bladder cancer, based on green tea consumption. Finally, on the basis of the accumulated data and the main findings, we discuss the potential usefulness of green tea as an antibladder cancer agent and the future direction of green tea-based treatment strategies for these patients.

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“…In addition, headache, polyuria and restlessness are well-known side-effects of caffeine, one of the substituents of green tea supplements (140 mg/ day, equivalent to approximately 200 mL of filtered coffee). These green tea related adverse events suggest that green tea was sufficiently absorbed, which is important because of its low oral bioavailability [13,41,42]. To ensure adequate green tea absorption, we administered the daily dose in two dosages and patients with known impaired drug absorption were excluded.…”

Section: Discussionmentioning

confidence: 99%

Influence of green tea consumption on endoxifen steady-state concentration in breast cancer patients treated with tamoxifen

Braal

Hussaarts

Seuren

et al. 2020

Breast Cancer Res Treat

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Background Many cancer patients use additional herbs or supplements in combination with their anti-cancer therapy. Green tea—active ingredient epigallocatechin-3-gallate (EGCG)—is one of the most commonly used dietary supplements among breast cancer patients. EGCG may alter the metabolism of tamoxifen. Therefore, the aim of this study was to investigate the influence of green tea supplements on the pharmacokinetics of endoxifen; the most relevant active metabolite of tamoxifen. Methods In this single-center, randomized cross-over trial, effects of green tea capsules on endoxifen levels were evaluated. Patients treated with tamoxifen for at least 3 months were eligible for this study. After inclusion, patients were consecutively treated with tamoxifen monotherapy for 28 days and in combination with green tea supplements (1 g twice daily; containing 300 mg EGCG) for 14 days (or vice versa). Blood samples were collected on the last day of monotherapy or combination therapy. Area under the curve (AUC0–24h), maximum concentration (Cmax) and minimum concentration (Ctrough) were obtained from individual plasma concentration–time curves. Results No difference was found in geometric mean endoxifen AUC0–24h in the period with green tea versus tamoxifen monotherapy (− 0.4%; 95% CI − 8.6 to 8.5%; p = 0.92). Furthermore, no differences in Cmax (− 2.8%; − 10.6 to 5.6%; p = 0.47) nor Ctrough (1.2%; − 7.3 to 10.5%; p = 0.77) were found. Moreover, no severe toxicity was reported during the whole study period. Conclusions This study demonstrated the absence of a pharmacokinetic interaction between green tea supplements and tamoxifen. Therefore, the use of green tea by patients with tamoxifen does not have to be discouraged.

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Population nutrikinetics of green tea extract

Cited by 55 publications

References 47 publications

Quantitative Analysis of Four Catechins from Green Tea Extract in Human Plasma Using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry for Pharmacokinetic Studies

Quantitative Analysis of Four Catechins from Green Tea Extract in Human Plasma Using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry for Pharmacokinetic Studies

Anticancer Effects of Green Tea and the Underlying Molecular Mechanisms in Bladder Cancer

Influence of green tea consumption on endoxifen steady-state concentration in breast cancer patients treated with tamoxifen

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