Bioavailability and antioxidant effect of epigallocatechin gallate administered in purified form versus as green tea extract in healthy individuals

Henning, Susanne M.; Niu, Yantao; Liu, Yong; Lee, Nicolas H; Hara, Yukihiko; Thames, Gail; Minutti, Rosario R.; Carpenter, Catherine L.; Wang, He-Jing; Heber, David

doi:10.1016/j.jnutbio.2005.03.003

Cited by 145 publications

(95 citation statements)

References 20 publications

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“…The inhibition of SN-38G and NPC formation observed in our study occurred at catechin concentrations (Ն10 M) that are unlikely to be found in the blood of individuals consuming green tea. Despite different modes of consumption, plasma concentrations of EGCG, as well as that of total catechins, do not exceed 2 M on average ( Donovan et al, 2004;Henning et al, 2005). Even though 4 times higher EGCG levels were found in the liver compared with plasma in rats (Schmidt et al, 2005), catechins are highly protein-bound in human plasma (Zhu et al, 2001).…”

Section: Discussionmentioning

confidence: 99%

Effects of Green Tea Compounds on Irinotecan Metabolism

et al. 2006

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ABSTRACT:The effects of green tea compounds on the metabolism of irinotecan have never been investigated. We aimed to study whether catechins [ (ECG), and 44% (EGC) of the hepatocyte preparations. Phenobarbital increased the formation of SN-38G in 100% of the same hepatocyte preparations. In Hep G2 cells, no increase in SN-38G formation was observed. With the exception of ECG in one liver, catechins did not increase UGT1A1 mRNA levels. NPC production was also significantly increased in 40% of the hepatocyte preparations for each catechin. However, the production of 6␤-hydroxytestosterone remained unaffected in other hepatocyte preparations. At pharmacologically relevant concentrations, catechins are unlikely to inhibit the formation of irinotecan inactive metabolites when administered concomitantly. The induction effect of catechins on UGT1A1 seems to be modest and highly variable. Catechins do not induce CYP3A4 activity. The effect of acute and prolonged use of green tea on the pharmacokinetics of irinotecan in patients remains to be evaluated.

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Section: Discussionmentioning

confidence: 99%

Effects of Green Tea Compounds on Irinotecan Metabolism

et al. 2006

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“…moreover, crYr is well tolerated in patients who are intolerant to statin drugs (6), suggesting that the lower amounts of active substances, enhanced action and more complete metabolism in comparison to a drug made from a single constituent may prevent adverse muscle side effects. Our group previously demonstrated similar interactions for phytochemicals in cranberry, pomegranate and green tea (7)(8)(9). in studies demonstrating synergistic interactions of a mixture of herbs against prostate cancer by isobolographic analysis, Rabdosia rubescens extract (rrE) was found to be particularly active among five herbs in a PC-SPES mixture (10).…”

Section: Introductionmentioning

confidence: 85%

Genomic and in vivo evidence of synergy of a herbal extract compared to its most active ingredient: Rabdosia rubescens vs. oridonin

Wong

Zhang

Kesler

et al. 2010

Experimental and Therapeutic Medicine

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Abstract. Rabdosia rubescens is a herbal root extract of traditional Chinese medicine (TCM) used to treat inflammatory diseases and oral cancers. a key principle of tcm is that multiple ingredients in a plant extract are more effective and less toxic than a single purified active ingredient or a purified drug derived from a plant product. Rabdosia rubescens extract (RRE) contains terpenoids and flavonoids, but the most active ingredient within the extract attributed to the inhibition of cancer is the kaurene diterpene, oridonin. in order to research synergy with a complete plant extract, the effects of rrE on the inhibition of prostate cancer cell proliferation were compared to the effects of pure oridonin alone in vitro. three groups of 8 Scid mice bearing human prostate cancer xenografts (lapc-4) were administered either rrE containing 0.02 mg/g oridonin, pure oridonin at a dose of 0.02 mg/g, or pure oridonin at a dose of 0.1 mg/g, by gavage for 5 days/week for 4 weeks. rrE and pure oridonin at 0.1 mg/g inhibited tumor growth to a similar extent, while oridonin at a dose of 0.02 mg/g did not. Therefore, in comparison to RRE, five times more pure oridonin was required to obtain equivalent prostate xenograft growth inhibition. Since the nuclear factor-κB signaling pathway and inflammation are implicated in prostate carcinogenesis, gene microarray analysis was conducted and demonstrated activation of genes by rrE that was not evident with oridonin treatment alone. this study demonstrated that genomic methods and xenograft studies are capable of demonstrating the benefits of the synergy of whole plant extracts rather than active ingredients isolated and purified as drugs. IntroductionBotanical extracts are used for the prevention and treatment of common conditions by 80% of the world's population according to estimates made by the World health Organization (1). drugs are produced from botanical sources by isolation and purification of the most active ingredients, while other substances in the raw fraction are separated. Synergistic interactions of mixtures of bioactive constituents and related substances or analogs in plant extracts have been proposed to occur with the most active ingredient. these interactions help explain the improved effectiveness of extracts containing multiple ingredients compared to drugs developed from single constituents.We previously studied the action and metabolism of chinese red yeast rice (Monascus purpureus Went) (crYr), a dietary supplement containing monacolins, one of which (monacolin K) is identical in structure to the statin drug lovastatin, and to unsaturated fatty acids and phytosterols capable of lowering low-density lipoprotein (ldl) cholesterol in humans (2-5). the apparent bioactivity of crYr containing 6 mg of Monacolin K was equivalent to 20 mg of purified lovastatin. moreover, crYr is well tolerated in patients who are intolerant to statin drugs (6), suggesting that the lower amounts of active substances, enhanced action and more complete metabolism in comparison to a d...

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“…Henning и соавт. [105], приводил к росту сывороточ-ного уровня МК (для экстракта зеленого чая -почти 10%). Справедливости ради стоит отметить, что участники ис-следования получали перед его началом легкий завтрак, состоящий из высокомолекулярных углеводов, что могло отразиться на результатах.…”

Section: мясо и морепродук тыunclassified

Diet in Gout and Hyperuricemia

Желябина¹,

Елисеев²

2017

Naučno-praktičeskaâ revmatologiâ

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The paper reviews the most important works devoted to the study of the impact of individual foods and food components on the risk of gout, its clinical manifestations and the level of uricemia. It considers some mechanisms probably underlying the impact of dietary patterns on the level of uricemia. It is shown that the available data on possible alterations in the diet with their proper application can considerably affect both the incidence of gout and the course of the current disease.

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Bioavailability and antioxidant effect of epigallocatechin gallate administered in purified form versus as green tea extract in healthy individuals

Cited by 145 publications

References 20 publications

Effects of Green Tea Compounds on Irinotecan Metabolism

Effects of Green Tea Compounds on Irinotecan Metabolism

Genomic and in vivo evidence of synergy of a herbal extract compared to its most active ingredient: Rabdosia rubescens vs. oridonin

Diet in Gout and Hyperuricemia

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