Ecabet sodium prevents the delay of wound repair in intestinal epithelial cells induced by hydrogen peroxide

Abstract

Recent studies showed that ecabet sodium (ES), a gastro-protective agent, also had a therapeutic effect on inflammation in ulcerative colitis. The aim of this study was to clarify the function of ES in wound repair in intestinal epithelial cells (IECs). The activation of signal proteins (ERK1/2 mitogen-activated protein kinase MAPK, and IkappaB-alpha) in IEC-6 cells after stimulation with 2.5 mg/ml of ES was assessed by Western blot. The induction of transforming growth factor (TGF)-beta1, TGF-alpha, and cyclooxygenase-2 (COX-2) mRNAs after the stimulation of IEC-6 cells with ES was assessed by reverse transcription ploymerase chain reaction (RT-PCR). IEC-6 cells were wounded and cultured for 24 h with various concentrations of ES in the absence or presence of 20 microM H2O2. Epithelial migration or proliferation was assessed by counting migrated or bromodeoxyuridine (BrdU)-positive cells observed across the wound border. We also assessed apoptotic epithelial cells after the culture. ES clearly activated ERK1/2 MAPK and slightly activated IkappaB-alpha. ES also enhanced the expression of TGF-alpha and COX-2 mRNAs. This enhancement was suppressed by a MAPK/Erk kinase (MEK) inhibitor. ES did not enhance epithelial migration in the absence of H2O2. In contrast, ES significantly decreased the number of apoptotic cells and prevented the reduction of epithelial migration (51.1%; P < 0.01) and proliferation (56%; P < 0.01) induced by H2O2. The function of ES was suppressed by a cyclooxygenase-2 (COX-2) inhibitor and by the MEK inhibitor, and partly suppressed by a nuclear factor (NF)-kappaB inhibitor. ES prevents the delay of wound repair in IEC-6 cells induced by H2O2, probably through the activation of ERK1/2 MAPK and the induction of COX-2.