Reactive oxygen species (ROS) are essential mediators in epidermal growth factor (EGF)-stimulated corneal epithelial cell proliferation, adhesion, migration, and wound healing.
EGF is an essential growth factor needed for epithelial cell proliferation and wound healing of the cornea, but the molecular mechanism is not understood. Although studies have shown that EGF in some non-phagocytic cells induces ROS generation, little is known about the role of ROS in corneal epithelial cells. Therefore, we examined the potential physiological role of ROS in corneal cell proliferation, adhesion and wound healing using rabbit or human corneal epithelial cells, and pig whole cornea organ culture as models. EGF (5 ng/ml)-induced ROS in serum-starved RCE or HCE cells were captured as DCFH fluorescence and detected by confocal microscopy. The elevation of ROS was eradicated when the cells were pretreated with an antioxidant N-acetylcysteine (NAC) or mannitol, or with inhibitor to NADPH oxidase (DPI), or to lipoxygenase (NDGA). EGF-induced ROS generation correlated with cell growth and activation of Akt and MAPK signaling pathways, while NAC eliminated all these effects. EGF-stimulated cell adhesion or migration in cell culture was greatly suppressed in the presence of NAC while EGF-facilitated epithelial cell wound healing in corneal organ culture was also blocked by NAC. This is the first demonstration of a novel ROS physiological function in corneal wound healing.
Huo
Yanan
Y
Department of Ophthalmology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 3 Qinchun Road East, Hangzhou, 310016 Zhejiang, China.
Qiu
Wen-Ya
WY
Pan
Qing
Q
Yao
Yu-Feng
YF
Xing
Kuiyi
K
Lou
Marjorie F
MF
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003315:Cornea / Q000473:pathology / Q000503:physiopathology; D065306:Corneal Injuries; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D019573:Epithelium, Corneal / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D018613:Microscopy, Confocal / Q000379:methods; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011817:Rabbits; D017382:Reactive Oxygen Species / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D034421:Sus scrofa; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology
D000975:Antioxidants; D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; D004815:Epidermal Growth Factor; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases