Neutralization of IL-18 attenuates lipopolysaccharide-induced myocardial dysfunction.
Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) have been implicated in cardiac dysfunction during endotoxemia. Because IL-18 is a proinflammatory cytokine known to mediate the production of TNF-alpha and IL-1beta and to induce the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), we hypothesized that neutralization of IL-18 would attenuate lipopolysaccharide (LPS)-induced cardiac dysfunction. Mice (C57BL/6) were injected with LPS (0.5 mg/kg ip) or vehicle (normal saline), and left ventricular developed pressure (LVDP) was determined by the Langendorff technique. LVDP was depressed by 38% at 6 h after LPS. LPS-induced myocardial dysfunction was associated with increased myocardial levels of TNF-alpha and IL-1beta as well as increased expression of ICAM-1/VCAM-1. Pretreatment with neutralizing anti-mouse IL-18 antibody attenuated LPS-induced myocardial dysfunction (by 92%) and was associated with reduced myocardial IL-1beta production (65% reduction) and ICAM-1/VCAM-1 expression (50% and 35% reduction, respectively). However, myocardial TNF-alpha levels were not influenced by neutralization of IL-18. In conclusion, neutralization of IL-18 protects against LPS-induced myocardial dysfunction. IL-18 may mediate endotoxemic myocardial dysfunction through induction of and/or synergy with IL-1beta, ICAM-1, and VCAM-1.
Department of Surgery, University of Colorado Health Sciences Center, 4200 E. Ninth Avenue, Box C-320, Denver, CO 80262, USA. christopher.raeburn@uchsc.edu
Christopher D
CD
Raeburn
Charles A
CA
Dinarello
Michael A
MA
Zimmerman
Casey M
CM
Calkins
Benjamin J
BJ
Pomerantz
Robert C
RC
McIntyre
Alden H
AH
Harken
Xianzhong
X
Meng
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology*; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism; D020382:Interleukin-18 / Q000276:immunology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000166:cytology / Q000378:metabolism; D009504:Neutrophils / Q000166:cytology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D000906:Antibodies; D007375:Interleukin-1; D020382:Interleukin-18; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1