Epigallocatechin-3-gallate suppresses NF-kappaB activation and phosphorylation of p38 MAPK and JNK in human astrocytoma U373MG cells.
Epigallocatechin-3-gallate (EGCG) is the major polyphenol component of green tea and is primarily responsible for the green tea effect. EGCG possesses two triphenolic groups in its structure. These groups are reported to be important with respect to anticarcinogenic and antioxidant effects. However, the anti-inflammatory effect of EGCG on Alzheimer's disease (AD) is still not fully understood. In this study, we investigated the effects of EGCG in attenuating the inflammatory response induced by interleukin (IL)-1beta+beta-amyloid (25-35) fragment (Abeta) in human astrocytoma, U373MG cells. EGCG significantly inhibited the IL-1beta+Abeta (25-35)-induced IL-6, IL-8, vascular endothelial growth factor (VEGF) and prostaglandin (PG)E(2) production at 24 h (P<.01). The maximal inhibition rate of IL-6, IL-8, VEGF and PGE(2) production by EGCG was approximately 54.40%, 56.01%, 69.06% and 47.03%, respectively. EGCG also attenuated the expression of cyclooxygenase-2 and activation of nuclear factor-kappaB induced by IL-1beta+Abeta (25-35). We demonstrated that EGCG suppresses IL-1beta+Abeta (25-35)-induced phosphorylation of the mitogen-activated protein kinase p38 and the c-Jun N-terminal kinase. In addition, EGCG induced the expression of mitogen-activated protein kinase phosphatase-1. These results provide new insight into the pharmacological actions of EGCG and its potential therapeutic application to various neurodegenerative diseases such as AD.
Kim
Su-Jin
SJ
Department of Pharmacology, College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul 130-701, Republic of Korea.
Jeong
Hyun-Ja
HJ
Lee
Kang-Min
KM
Myung
Noh-Yil
NY
An
Nyeon-Hyoung
NH
Yang
Woong Mo
WM
Park
Seong Kyu
SK
Lee
Hye-Jung
HJ
Hong
Seung-Heon
SH
Kim
Hyung-Min
HM
Um
Jae-Young
JY
D016229:Amyloid beta-Peptides / Q000235:genetics / Q000378:metabolism; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001254:Astrocytoma; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D006801:Humans; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
D016229:Amyloid beta-Peptides; D000893:Anti-Inflammatory Agents; D053583:Interleukin-1beta; D015850:Interleukin-6; D016209:Interleukin-8; D016328:NF-kappa B; D010446:Peptide Fragments; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C074636:amyloid beta-protein (25-35); D002392:Catechin; C045651:epigallocatechin gallate; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone