|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
INFLAMMATION/IMMUNITY/MEDIATORS
Centre for Critical Illness Research, Lawson Health Research Institute, London, Ontario, Canada
Submitted 31 July 2007 ; accepted in final form 5 November 2007
Recent studies suggest that exogenously administered CO is beneficial for the resolution of acute inflammation. In this study, we assessed the role of CO liberated from a systemically administered tricarbonyldichlororuthenium-(II)-dimer (CORM-2) on modulation of liver inflammation during sepsis. Polymicrobial sepsis in mice was induced by cecal ligation and perforation (CLP). CORM-2 (8 mg/kg iv) was administered immediately after CLP induction, and neutrophil [polymorphonuclear leukocyte (PMN)] tissue accumulation, activation of transcription factor, NF-
B, and changes in adhesion molecule ICAM-1 expression (inflammation-relevant markers) were assessed in murine liver 24 h later. In addition, the effects and potential mechanisms of CORM-2-released CO in modulation of vascular endothelial cell proinflammatory responses were assessed in vitro. To this end, human umbilical vein endothelial cells (HUVEC) were stimulated with LPS (1 µg/ml) in the presence or absence of CORM-2 (10–100 µM) and production of intracellular reactive oxygen species (ROS), (DHR123 oxidation) and NO (DAF-FM nitrosation) and subsequent activation of NF-
B were assessed 4 h later. In parallel, expression of ICAM-1 and inducible NO synthase (iNOS) proteins along with PMN adhesion to LPS-challenged HUVEC were also assessed. Induction of CLP resulted in increased PMN accumulation, ICAM-1 expression, and activation of NF-
B in the liver of septic mice. These effects were significantly attenuated by systemic administration of CORM-2. In in vitro experiments, CORM-2-released CO attenuated LPS-induced production of ROS and NO, activation of NF-
B, increase in ICAM-1 and iNOS protein expression and PMN adhesion to LPS-stimulated HUVEC. Taken together, these findings indicate that CO released from systemically administered CORM-2 provides anti-inflammatory effects by interfering with NF-
B activation and subsequent downregulation of proadhesive vascular endothelial cell phenotype in the liver of septic mice.
endothelial cells; oxidative stress; nitric oxide; NF-
B
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |