Abstract
Reactive oxygen species (ROS) play a crucial role in acute lung injury. Tissue inflammation, the increased vascular permeability, and plasma exudation are cardinal features of acute lung injury. Angiopoietin-1 (Ang1) has potential therapeutic applications in preventing vascular leakage and also has beneficial effects in several inflammatory disorders. Recently developed COMP-Ang1 is more potent than native Ang1 in phosphorylating tyrosine kinase with immunoglobulin and EGF homology domain 2 receptor in endothelial cells. However, there are no data on effects and related molecular mechanisms of COMP- Ang1 on ROS-induced acute lung injury. We used hydrogen peroxide (H2O2)- inhaled mice to evaluate the effect of COMP-Ang1 on pulmonary inflammation, bronchial hyper-responsiveness, and vascular leakage in acute lung injury. The results have revealed that VEGF expression, the levels of IL-4, TNF-α, IL-1β, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 in lungs, the levels of hypoxia-inducible factor-1α (HIF-1α) and NF-κB in nuclear protein extracts, phosphorylation of Akt, and vascular permeability were increased after inhalation of H 2O2 and that the administration of COMP-Ang1 markedly reduced airway hyper-responsiveness, pulmonary inflammation, plasma extravasation, and the increases of cytokines, adhesion molecules, and VEGF in lungs treated with H2O2. We have also found that the activation of HIF-1α and NF-κB and the increase of phosphoinositide 3-kinase activity in lung tissues after H2O2 inhalation were decreased by the administration of COMP-Ang1. These results suggest that COMP-Ang1 ameliorates ROS-induced acute lung injury through attenuating vascular leakage and modulating inflammatory mediators.
Original language | English |
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Pages (from-to) | 320-331 |
Number of pages | 12 |
Journal | Experimental and Molecular Medicine |
Volume | 40 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2008 Jun 30 |
Externally published | Yes |
Keywords
- Angiopoietin-1
- COMP-Ang1 fusion protein
- Capillary permeability
- Hydrogen peroxide
- Lung
- Pneumonia
- Reactive oxygen species
- Vascular endothelial growth factor A
ASJC Scopus subject areas
- Biochemistry
- Molecular Medicine
- Molecular Biology
- Clinical Biochemistry