Inhibition of IL-8 production by green tea polyphenols in human nasal fibroblasts and A549 epithelial cells.
The attraction of leukocytes to tissues is essential in order for inflammation and the host response to infection to occur. Airway inflammation is a very common cause illness with a substantial impact on health care. Neutrophils play an essential role in the host defense and in inflammation, but the latter may trigger and sustain the pathogenesis of a range of acute and chronic diseases. Infiltration of neutrophils occurs as a response to chemoattractant molecules by resident tissue cells. The recruitment of neutrophils in airway inflammation may account for the generation of IL-8. To evaluate the effectiveness of green tea polyphenols in the modulation of airway inflammation through the blocking of neutrophil chemokine production, nasal mucosal fibroblasts and A549 bronchial epithelial cells were analyzed for the production of IL-8. Both nasal mucosal fibroblasts and bronchial epithelial cells produced significant amounts of IL-8 through stimulation of IL-1beta. Tea polyphenols were very effective in the inhibition of IL-8 production. Among the polyphenols tested, EGCG and ECG showed strong inhibitory activity in dose-dependent manners. EGC and EC showed moderate inhibition at 48 h culture, whereas (-)catechin was not effective. Production of IL-8 after stimulation by proinflammatory cytokines in both nasal fibroblasts and bronchial epithelial cells was significantly blocked by pretreatment with green tea polyphenols.
Kim
In-Bae
IB
Department of Microbiology, College of Medicine, Kyung Hee University, Dongdaemun-gu, Seoul, Korea.
Kim
Dong-Young
DY
Lee
Su-Jin
SJ
Sun
Min-Jung
MJ
Lee
Myung-Sook
MS
Li
Hua
H
Cho
Jeong-Je
JJ
Park
Cheung-Seog
CS
D015153:Blotting, Western; D001980:Bronchi / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D028241:Camellia sinensis / Q000737:chemistry*; D002460:Cell Line; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000187:drug effects* / Q000276:immunology; D005347:Fibroblasts / Q000187:drug effects* / Q000276:immunology; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D053583:Interleukin-1beta / Q000276:immunology; D016209:Interleukin-8 / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000276:immunology; D009297:Nasal Mucosa / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology*; D059808:Polyphenols; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
D005419:Flavonoids; D053583:Interleukin-1beta; D016209:Interleukin-8; D010636:Phenols; D059808:Polyphenols; D014409:Tumor Necrosis Factor-alpha