RRC ID 77228
Author Teranishi S, Kimura K, Kawamoto K, Nishida T.
Title Protection of human corneal epithelial cells from hypoxia-induced disruption of barrier function by keratinocyte growth factor.
Journal Invest Ophthalmol Vis Sci
Abstract PURPOSE:The possible detrimental effect of hypoxia on the barrier function of corneal epithelial cells and whether keratinocyte growth factor (KGF) might protect against such an effect were investigated.
METHODS:Simian virus 40-transformed human corneal epithelial (HCE) cells were cultured for 4 days to allow the establishment of barrier function. They were then deprived of serum for 24 hours before exposure to 1% (hypoxia) or 21% (normoxia) oxygen for 24 hours. Barrier function was evaluated by measurement of transepithelial electrical resistance (TER). The localization of ZO-1 and occludin was determined by immunofluorescence microscopy, and the expression of these tight junctional proteins as well as the phosphorylation of the mitogen-activated protein kinases ERK, p38, and JNK were examined by immunoblot analysis.
RESULTS:Hypoxia induced a decrease in the TER of HCE cells compared with that of cells maintained under normoxia. The localization of ZO-1 at cell-cell borders was disrupted by hypoxia, whereas the distribution of occludin was not affected. Hypoxia also induced the downregulation of ZO-1 and a decrease in the phosphorylation of ERK without affecting the phosphorylation of p38 or JNK. All these effects of hypoxia were inhibited by KGF. The effects of KGF on TER and ZO-1 localization in cells exposed to hypoxia were inhibited by PD98059, an inhibitor of ERK signaling. Neither hypoxia nor KGF exhibited mitogenic or cytotoxic effects in HCE cells.
CONCLUSIONS:Hypoxia induces disruption of the barrier function of HCE cells by eliciting the redistribution and degradation of ZO-1, and this effect is inhibited by KGF in a manner dependent on ERK activation.
Volume 49(6)
Pages 2432-7
Published 2008-6-1
DOI 10.1167/iovs.07-1464
PII iovs.07-1464
PMID 18362114
MeSH Cell Line, Transformed Cell Membrane Permeability / drug effects Cell Proliferation Cell Transformation, Viral Electric Impedance Epithelium, Corneal / drug effects* Epithelium, Corneal / metabolism* Fibroblast Growth Factor 7 / pharmacology* Humans Hypoxia / metabolism* Immunoblotting JNK Mitogen-Activated Protein Kinases / metabolism Membrane Proteins / metabolism Microscopy, Fluorescence Mitogen-Activated Protein Kinase 1 / metabolism Mitogen-Activated Protein Kinase 3 / metabolism Occludin Phosphoproteins / metabolism Phosphorylation Tight Junctions / drug effects Zonula Occludens-1 Protein p38 Mitogen-Activated Protein Kinases / metabolism
IF 3.47
Human and Animal Cells HCE-T(RCB2280)