Tea polyphenols epigallocatechin gallate

Dong, Z., Ma, W.-Y., Huang, C.,Yang, C. S., 1997, Inhibition of tumor promoter induced activator protein 1 activation and cell transformation by tea polyphenols, (-)-epigallocatechin gallate and theaflavins, Cancer Res. 57 4414-4419. 

PhIP. The inhibition by tea of these two tests, which are indicators of genotoxicity, suggests that naturally occurring plant extracts can modify metabolic activation of HAAs. Tea polyphenols, epigallocatechin gallate from green tea and theaflavin gal-late from black tea, display similar inhibiting action in both tests (see ref. 318). 

Bursill, C. A., Roach, P. D. (2006). Modulation of cholesterol metabolism by the green tea polyphenol (-)-epigallocatechin gallate in cultured human liver (HepG2) cells. J. Agric. Food Chem., 54, 1621-1626. 

FIGURE 8.19 Proposed scavenging mechanism of epigallocatechin gallate to nitrite ions. (From Panzella, L., Manini, P., Napolitano, A., and d Ischia, M. 2005. The acid-promoted reaction of the green tea polyphenol epigallocatechin gallate with nitrite ions. Chem. Res. Toxicol. 18 722-29. With permission.)... 

Liberto M, Cobrinik D (2000) Growth factor-dependent induction of p21(CIPl) by the green tea polyphenol, epigallocatechin gallate. Cancer Lett 154 151-161... 

Tobi SE, Gilbert M, Paul N and McMillan TJ. 2002. The green tea polyphenol, epigallocatechin-3-gallate, protects against the oxidative cellular and genotoxic damage of UVA radiation. Int J Cancer 102(5) 439-444. 

Katiyar, S.K. and Mukhtar, H., Green tea polyphenol (-)-epigallocatechin-3-gallate treatment to mouse skin prevents UVB-induced infiltration of leukocytes, depletion of antigen-presenting cells, and oxidative stress, J Leukoc Biol, 69, 719, 2001. 

Mandel S, Weinreb O, Amit T, Cell signaling pathways in the neuroprotective actions of the green tea polyphenol (—)-epigallocatechin-3-gallate, implications for neurodegenerative diseases, JNeurochem 88 1555—1569, 2004. 

Fang, M.Z., Wang, Y, Ai, N Hou, Z Sun, Y, Lu, H., Welsh, W. and Yang, C.S. (2003) Tea polyphenol (—)-epigallocatechin-3-gallate inhibits DNA methyltransferase and reactivates methylation-silenced genes in cancer cell lines. Cancer Research, 63, 7563-7570. 

Hastak K, Agarwal MK, Mukhtar H, Agarwal ML. 2005. Ablation of either p21 or Bax prevents p53-dependent apoptosis induced by green tea polyphenol epigallocatechin-3-gallate. FASEB J 19 789-791. 

Katiyar SK, Afaq F, Azizuddin K, Mukhtar H. 2001. Inhibition of UVB-induced oxidative stress-mediated phosphorylation of mitogen-activated protein kinase signaling pathways in cultured human epidermal keratinocytes by green tea polyphenol (—)-epigallocatechin-3-gallate. Toxicol Appl Pharmacol 176 110-117. 

Sakata R, Ueno T, Nakamura T, Sakamoto M, Torimura T, Sata M. 2004. Green tea polyphenol epigallocatechin-3-gallate inhibits platelet-derived growth factor-induced proliferation of human hepatic stellate cell line LI90. J Hepatol 40 52-59. 

Kalfon L, Youdim MB, Mandel SA. 2007. Green tea polyphenol (-)-epigallocatechin-3-gallate promotes the rapid protein kinase C- and proteasome-mediated degradation of Bad Implications for neuroprotection. J Neurochem 100 992-1002. 

Levites Y, Weinreb O, Maor G, Youdim MB, Mandel S. 2001. Green tea polyphenol (—)-epigallocatechin-3-gallate prevents N-mcthyl-4-phcnyl-l, 2,3,6-tctrahydropyri-dine-induced dopaminergic neurodegeneration. J Neurochem 78 1073-1082. 

Spinella F, Rosano L, Di Castro V, Decandia S, Albini A, Nicotra MR, Natali PG, Bagnato A. 2006. Green tea polyphenol epigallocatechin-3-gallate inhibits the endothelin axis and downstream signaling pathways in ovarian carcinoma. Mol Cancer Ther 5 1483-1492. 

Levites, Y., Amit, T., Mandel, S., and Youdim, M.B., Neuroprotection and neurorescue against Abeta toxicity and PKC-dependent release of nonamyloidogenic soluble precursor protein by green tea polyphenol (-)-epigallocatechin-3-gallate. FASEB J, May, 17(8), 952-954, 2003. 

Ahmed, S. et al. Green tea polyphenol epigallocatechin-3-gallate (EGCG) differentially inhibits interleukin-1 beta-induced expression of matrix metalloproteinase-1 and -13 in human chondrocytes. J Pharmacol Exp Ther. 308, 767, 2004. 

Similar to the antioxidant properties of other low molecular weight polyphenols, (-)-epigallocatechin gallate, a main component of green teas, has been known to be a potent antioxidant and reduce free radical-induced lipid perox-... 

Yang, R, Oz, H. S., Barve, S., de Villiers, W. J., McClain, C. J., Varilek, G. W. (2001). The green tea polyphenol (-)-epigallocatechin-3-gallate blocks nuclear factor-kappa B activation by inhibiting 1 kappa B kinase activity in the intestinal epithelial cell line IEC-6. Molecular Pharmacology, 60, 528-533. 

Levites, Y, Weinreb, O., Maor, G., Youdim, M.B.H., and Mandel, S. Green tea polyphenol (-)-epigallocatechin-3-gallate prevents N-methyM-phenyl-1,2,3,6- tet-rahydropyridine-induced dopaminergic neurodegeneration, J. Neurochem., 78, 1073-1082, 2001. 

Nomura, M., Ma, W.Y., Chen, N., Bode, A.M., and Dong, Z., Inhibition of 12-0-tetra- decanoylphorbol-13-acetate-induced NFkB activation by tea polyphenols, (-)-epigallocatechin-3-gallate and theaflavins. Carcinogenesis, 21 (10), 1885-1890, 2000. 

Ahmed, S., Rahman, A., Hasnain, A., Lalonde, M., Goldberg, V. M., and Haqqi, T. M. 2002. Green tea polyphenol epigallocatechin-3-gallate inhibits the IL-1 beta-induced activity and expression of cyclooxygenase-2 and nitric oxide synthase-2 in human chondrocytes. Free Radic. Biol. Med. 33 1097-105. 

Tea is the most widely consumed beverage in the world and may be effective in the prevention and treatment of diabetes. Tea polyphenols, also know as catechins, are considered to be the active components responsible for prevention of diabetes. The major polyphenols in green tea include (-)-epigallocatechin gallate (EGCG), (-)-epi-gallocatechin (EGC), (-)-epicatechin-3-gallate (EGG), and (-)-epicatechin (EC). 

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