![]() |
|
|




Section of Critical Care Medicine, Childrens Medical Center, and
* Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912; and
Division of Critical Care Medicine, Cincinnati Childrens Hospital Medical Center, and Childrens Hospital Research Foundation, Cincinnati, OH 45229
3To whom correspondence should be addressed. E-mail: dewheeler{at}mcg.edu.
Polyphenolic components of green tea, such as epigallocatechin-3-gallate (EGCG), have potent anti-inflammatory properties. We previously showed that EGCG inhibits tumor necrosis factor-
(TNF-
)mediated activation of the nuclear factor-
B (NF-
B) pathway, partly through inhibition of I
B kinase (IKK). The NF-
B pathway may also be activated in response to interleukin-1ß (IL-1ß) stimulation through a distinct signal transduction pathway. We therefore hypothesized that EGCG inhibits IL-1ß-mediated activation of the NF-
B pathway. Because the gene expression of interleukin-8 (IL-8), the major human neutrophil chemoattractant, is dependent on activation of NF-
B, IL-8 gene expression in human lung epithelial (A549) cells treated with human IL-1ß was used as a model of IL-1ß signal transduction. The EGCG markedly inhibited IL-1ßmediated IL-1ß receptorassociated kinase (IRAK) degradation and the signaling events downstream from IRAK degradation: IKK activation, I
B
degradation, and NF-
B activation. In addition, EGCG inhibited phosphorylation of the p65 subunit of NF-
B. The functional consequence of this inhibition was evident by inhibition of IL-8 gene expression. Therefore, the green tea polyphenol EGCG is a potent inhibitor of IL-1ß signal transduction in vitro. The proximal mechanisms of this effect involve inhibition of IRAK-dependent signaling and phosphorylation of p65.
KEY WORDS: transcription factors inflammation signal transduction chemokines polyphenols
This article has been cited by other articles:
![]() |
K.-C. Choi, M. G. Jung, Y.-H. Lee, J. C. Yoon, S. H. Kwon, H.-B. Kang, M.-J. Kim, J.-H. Cha, Y. J. Kim, W. J. Jun, et al. Epigallocatechin-3-Gallate, a Histone Acetyltransferase Inhibitor, Inhibits EBV-Induced B Lymphocyte Transformation via Suppression of RelA Acetylation Cancer Res., January 15, 2009; 69(2): 583 - 592. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. L. McKay and J. B. Blumberg Roles for Epigallocatechin Gallate in Cardiovascular Disease and Obesity: An Introduction J. Am. Coll. Nutr., August 1, 2007; 26(4): 362S - 365S. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Ishida, C. Kohda, Y. Yanagawa, H. Miyaoka, and T. Shimamura Epigallocatechin gallate suppresses expression of receptor activator of NF-{kappa}B ligand (RANKL) in Staphylococcus aureus infection in osteoblast-like NRG cells J. Med. Microbiol., August 1, 2007; 56(8): 1042 - 1046. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. A. Ruiz, A. Braune, G. Holzlwimmer, L. Quintanilla-Fend, and D. Haller Quercetin Inhibits TNF-Induced NF-{kappa}B Transcription Factor Recruitment to Proinflammatory Gene Promoters in Murine Intestinal Epithelial Cells J. Nutr., May 1, 2007; 137(5): 1208 - 1215. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. A. Davis, J. A. Polagruto, G. Valacchi, A. Phung, K. Soucek, C. L. Keen, and M. E. Gershwin Effect of Apple Extracts on NF-{kappa}B Activation in Human Umbilical Vein Endothelial Cells. Experimental Biology and Medicine, May 1, 2006; 231(5): 594 - 598. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. A. Ruiz and D. Haller Functional Diversity of Flavonoids in the Inhibition of the Proinflammatory NF-{kappa}B, IRF, and Akt Signaling Pathways in Murine Intestinal Epithelial Cells J. Nutr., March 1, 2006; 136(3): 664 - 671. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. K. Andreadi, L. M. Howells, P. A. Atherfold, and M. M. Manson Involvement of Nrf2, p38, B-Raf, and Nuclear Factor-{kappa}B, but Not Phosphatidylinositol 3-Kinase, in Induction of Hemeoxygenase-1 by Dietary Polyphenols Mol. Pharmacol., March 1, 2006; 69(3): 1033 - 1040. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Hsu, D. P. Dickinson, H. Qin, C. Lapp, D. Lapp, J. Borke, D. S. Walsh, W. B. Bollag, H. Stoppler, T. Yamamoto, et al. Inhibition of Autoantigen Expression by (-)-Epigallocatechin-3-gallate (the Major Constituent of Green Tea) in Normal Human Cells J. Pharmacol. Exp. Ther., November 1, 2005; 315(2): 805 - 811. [Abstract] [Full Text] [PDF] |
||||