Abstract
The influx of neutrophils into the lung is a sentinel event in LPS-induced acute lung inflammation. Previous studies have shown that systemic inhibition of p38 decreases LPS-induced neutrophil influx into the alveolar space but has no effect on pulmonary parenchymal neutrophil accumulation or on microvascular leak, indicating other pathways are important in LPS-induced acute lung inflammation. This study examined the role of c-Jun N-terminal kinase in LPS-induced acute lung inflammation. Systemic inhibition of c-Jun N-terminal kinase, with the specificc-Jun N-terminal kinase inhibitor SP600125, decreased the LPS-induced accumulation of neutrophils into the lung parenchyma and alveolar space. In addition, increases in microvascular leak after LPS exposure were diminished by c-jun N-terminal kinase inhibition. To determine mechanisms by which systemic c-Jun N-terminal kinase inhibition decreased pulmonary neutrophil influx, LPS and tumor necrosis factor α (TNF-α-)-induced neutrophil actin assembly and retention were examined. Neutrophil actin assembly was decreased after LPS and TNF-α stimulation with SP600125 pretreatment, as well as LPS-induced neutrophil retention. Finally, c-Jun N-terminal kinase inhibition decreased Cdc42 activation after LPS or TNF-α stimulation, thereby providing one mechanism by which c-Jun N-terminal kinase inhibition decreased actin assembly, and thereby pulmonary neutrophil accumulation.
Original language | English (US) |
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Pages (from-to) | 978-986 |
Number of pages | 9 |
Journal | American journal of respiratory and critical care medicine |
Volume | 171 |
Issue number | 9 |
DOIs | |
State | Published - May 1 2005 |
Keywords
- Inflammation
- Lipopolysaccharide
- Lung
- Neutrophil