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Title: TNF-{alpha} promotes cell survival through stimulation of K{sup +} channel and NF{kappa}B activity in corneal epithelial cells

Abstract

Tumor necrosis factor (TNF-{alpha}) in various cell types induces either cell death or mitogenesis through different signaling pathways. In the present study, we determined in human corneal epithelial cells how TNF-{alpha} also promotes cell survival. Human corneal epithelial (HCE) cells were cultured in DMEM/F-12 medium containing 10% FBS. TNF-{alpha} stimulation induced activation of a voltage-gated K{sup +} channel detected by measuring single channel activity using patch clamp techniques. The effect of TNF-{alpha} on downstream events included NF{kappa}B nuclear translocation and increases in DNA binding activities, but did not elicit ERK, JNK, or p38 limb signaling activation. TNF-{alpha} induced increases in p21 expression resulting in partial cell cycle attenuation in the G{sub 1} phase. Cell cycle progression was also mapped by flow cytometer analysis. Blockade of TNF-{alpha}-induced K{sup +} channel activity effectively prevented NF{kappa}B nuclear translocation and binding to DNA, diminishing the cell-survival protective effect of TNF-{alpha}. In conclusion, TNF-{alpha} promotes survival of HCE cells through sequential stimulation of K{sup +} channel and NF{kappa}B activities. This response to TNF-{alpha} is dependent on stimulating K{sup +} channel activity because following suppression of K{sup +} channel activity TNF-{alpha} failed to activate NF{kappa}B nuclear translocation and binding to nuclear DNA.

Authors:
 [1];  [2];  [3]
  1. Division of Molecular Medicine, Harbor-UCLA Medical Center, David Geffen School of Medicine, University of California Los Angeles, 1124 W. Carson Street, C-2, Torrance, CA 90502 (United States)
  2. Department of Biological Sciences, SUNY College of Optometry, New York, NY 10010 (United States)
  3. Division of Molecular Medicine, Harbor-UCLA Medical Center, David Geffen School of Medicine, University of California Los Angeles, 1124 W. Carson Street, C-2, Torrance, CA 90502 (United States). E-mail: lluou@ucla.edu
Publication Date:
OSTI Identifier:
20717684
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 311; Journal Issue: 1; Other Information: DOI: 10.1016/j.yexcr.2005.08.020; PII: S0014-4827(05)00386-1; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; APOPTOSIS; CELL CYCLE; DNA; LIMBS; MONOCLINIC LATTICES; POTASSIUM IONS; STIMULATION; TRANSLOCATION

Citation Formats

Wang Ling, Reinach, Peter, and Lu, Luo. TNF-{alpha} promotes cell survival through stimulation of K{sup +} channel and NF{kappa}B activity in corneal epithelial cells. United States: N. p., 2005. Web. doi:10.1016/j.yexcr.2005.08.020.
Wang Ling, Reinach, Peter, & Lu, Luo. TNF-{alpha} promotes cell survival through stimulation of K{sup +} channel and NF{kappa}B activity in corneal epithelial cells. United States. doi:10.1016/j.yexcr.2005.08.020.
Wang Ling, Reinach, Peter, and Lu, Luo. Tue . "TNF-{alpha} promotes cell survival through stimulation of K{sup +} channel and NF{kappa}B activity in corneal epithelial cells". United States. doi:10.1016/j.yexcr.2005.08.020.
@article{osti_20717684,
title = {TNF-{alpha} promotes cell survival through stimulation of K{sup +} channel and NF{kappa}B activity in corneal epithelial cells},
author = {Wang Ling and Reinach, Peter and Lu, Luo},
abstractNote = {Tumor necrosis factor (TNF-{alpha}) in various cell types induces either cell death or mitogenesis through different signaling pathways. In the present study, we determined in human corneal epithelial cells how TNF-{alpha} also promotes cell survival. Human corneal epithelial (HCE) cells were cultured in DMEM/F-12 medium containing 10% FBS. TNF-{alpha} stimulation induced activation of a voltage-gated K{sup +} channel detected by measuring single channel activity using patch clamp techniques. The effect of TNF-{alpha} on downstream events included NF{kappa}B nuclear translocation and increases in DNA binding activities, but did not elicit ERK, JNK, or p38 limb signaling activation. TNF-{alpha} induced increases in p21 expression resulting in partial cell cycle attenuation in the G{sub 1} phase. Cell cycle progression was also mapped by flow cytometer analysis. Blockade of TNF-{alpha}-induced K{sup +} channel activity effectively prevented NF{kappa}B nuclear translocation and binding to DNA, diminishing the cell-survival protective effect of TNF-{alpha}. In conclusion, TNF-{alpha} promotes survival of HCE cells through sequential stimulation of K{sup +} channel and NF{kappa}B activities. This response to TNF-{alpha} is dependent on stimulating K{sup +} channel activity because following suppression of K{sup +} channel activity TNF-{alpha} failed to activate NF{kappa}B nuclear translocation and binding to nuclear DNA.},
doi = {10.1016/j.yexcr.2005.08.020},
journal = {Experimental Cell Research},
number = 1,
volume = 311,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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