Mitogen-activated protein kinases modulate H(2)O(2)-induced apoptosis in primary rat alveolar epithelial cells.

Abstract

Increasing evidence suggests a role for apoptosis in the maintenance of the alveolar epithelium under normal and pathological conditions. However, the signaling pathways modulating alveolar type II (ATII) cell apoptosis remain poorly defined. Here we investigated the role of MAPKs as modulators of oxidant-mediated ATII cell apoptosis using in vitro models of H(2)O(2)-stress. H(2)O(2), delivered either as a bolus or as a flux, lead to time- and concentration-dependent increases in ATII cells apoptosis. Increased apoptosis in primary rat ATII cells was detected at H(2)O(2) concentrations and production rates in the physiological range (1 microM) and peaked at 100 microM H(2)O(2). Immortalized rat lung epithelial cells (RLE), in contrast, required millimolar concentration of H(2)O(2) for maximal responses. H(2)O(2)-induced apoptosis was preceded by rapid activation of all three classes of mitogen-activated protein kinases (MAPKs): ERK, JNK, and p38. Specific inhibition of JNK using antisense oligonucleotides and ERK and p38 using PD98059 or SB202190, respectively, indicated a pro-apoptotic role for JNK pathway and an anti-apoptotic role for ERK- and p38-initiated signaling events. Our data show that the balance between the activation of JNK, ERK, and p38 is a critical determinant of cell fate, suggesting that pharmacological interventions on the MAPK pathways may be useful in the treatment of oxidant-related lung injury.

• Authors: Helotonio Carvalho, Pablo Evelson, Samuel Sigaud, Beatriz González-Flecha
• Journal: Journal of cellular biochemistry (J Cell Biochem) Vol. 92 Issue 3 Pg. 502-13 (Jun 01 2004) ISSN: 0730-2312 [Print] United States
• PMID: 15156562 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
• Copyright: Copyright 2004 Wiley-Liss, Inc.

Chemical References

• Oligonucleotides, Antisense
• Hydrogen Peroxide
• JNK Mitogen-Activated Protein Kinases
• Mitogen-Activated Protein Kinases
• MAP Kinase Kinase 4
• Mitogen-Activated Protein Kinase Kinases

Topics

• Animals
• Apoptosis (drug effects)
• Cells, Cultured
• Dose-Response Relationship, Drug
• Enzyme Activation
• Epithelial Cells (cytology, drug effects, metabolism)
• Hydrogen Peroxide (pharmacology)
• JNK Mitogen-Activated Protein Kinases (antagonists & inhibitors, genetics)
• MAP Kinase Kinase 4
• Mitogen-Activated Protein Kinase Kinases (antagonists & inhibitors, genetics)
• Mitogen-Activated Protein Kinases (antagonists & inhibitors, metabolism)
• Oligonucleotides, Antisense
• Oxidative Stress (drug effects)
• Phosphorylation (drug effects)
• Pulmonary Alveoli (cytology, drug effects, metabolism)
• Rats
• Rats, Sprague-Dawley
• Time Factors