Epicatechin gallate suppresses oxidative stress-induced MUC5AC overexpression by interaction with epidermal growth factor receptor.
The goal of this study was to investigate the effect of epicatechin gallate (ECG), a component of green tea polyphenols, on the signal pathway for oxidative stress-induced intracellular reactive oxygen species (ROS) generation and MUC5AC overexpression in normal human nasal epithelial (NHNE) cells. Passage-2 NHNE cells were used, and ECG was administered before stimulation with exogenous hydrogen peroxide (H(2)O(2)). MUC5AC gene and protein levels were measured by real-time PCR and dot blot analysis. Western blot analysis and immunocytofluorescence study were performed for detecting the activity of epidermal growth factor receptor (EGFR). Exogenous H(2)O(2) increases intracellular ROS generation, leading to the overexpression of MUC5AC. The phosphorylation and internalization of EGFR were associated with this ROS generation. ECG decreased the phosphorylation and internalization of EGFR at the cell surface of NHNE cells, resulting in the attenuation of exogenous H(2)O(2)-induced intracellular ROS generation and MUC5AC overexpression. ECG may be a therapeutic material against oxidative stress-induced ROS generation and mucus hypersecretion in airways.
Kim
Hyun Jik
HJ
Department of Otolaryngology-Head and Neck Surgery, Chung-Ang University College of Medicine, Seoul, Korea.
Ryu
Ji-Hwan
JH
Kim
Chang-Hoon
CH
Lim
Jun Wan
JW
Moon
Uk Yeol
UY
Lee
Gyu Ho
GH
Lee
Jeung-Gweon
JG
Baek
Seung Joon
SJ
Yoon
Joo-Heon
JH
D000975:Antioxidants / Q000494:pharmacology*; D015153:Blotting, Western; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D049109:Cell Proliferation; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000378:metabolism; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D055271:Mucin 5AC / Q000235:genetics / Q000378:metabolism*; D009297:Nasal Mucosa / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects*; D010766:Phosphorylation / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects
D000975:Antioxidants; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D016877:Oxidants; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D002392:Catechin; C062669:epicatechin gallate; D006861:Hydrogen Peroxide; C512478:EGFR protein, human; D066246:ErbB Receptors