| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Circulation. 2003;108:2387.)
© 2003 American Heart Association, Inc.
Basic Science Reports |
From the Departments of Pathology (S.T.T., L.L., S.M.F., J.W.B.), Medicine (Molecular Cardiology) (W.M., K.M., S.M.F., R.N.K.), Cell Biology (K.M., R.N.K.), and Microbiology and Immunology (J.W.B.), Albert Einstein College of Medicine, Bronx, NY.
Correspondence to Richard N. Kitsis, Departments of Medicine (Molecular Cardiology) and Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461. E-mail kitsis{at}aecom.yu.edu
Received October 10, 2002; de novo received June 6, 2003; accepted July 9, 2003.
Background The timely reperfusion of ischemic myocardium limits infarction, but components of reperfusion, such as inflammation, may be injurious. The chemokine receptor CXCR2 mediates neutrophil chemotaxis. CXCR2 activation also inhibits hypoxia-induced death of isolated cardiac myocytes. This study assesses whether CXCR2 mediates protection in the intact heart and, if so, the magnitude of this protection relative to CXCR2-mediated chemotaxis of potentially damaging inflammatory cells.
Methods and Results After ischemia-reperfusion in vivo, CXCR2-/- mice exhibited infarcts that were 50.5% smaller (P<0.05) with 44.3% fewer inflammatory cells (P<0.05) than wild type mice. These data suggest that in this model, CXCR2-mediated chemotaxis may be important in myocardial cell death. To isolate the role of CXCR2 specifically on blood cells, adoptive transfer experiments were performed. After ischemia-reperfusion, infarcts were 53.4% smaller (P<0.05) and contained 65.0% fewer inflammatory cells (P<0.05) in lethally irradiated wild type mice reconstituted with CXCR2-/- compared with wild type bone marrow. Thus, CXCR2 on blood cells is important in myocardial damage, most likely because of CXCR2-mediated chemotaxis. To unmask whether CXCR2 mediates direct myocardial protection in the intact heart, wild type and CXCR2-/- hearts were studied in the absence of blood using Langendorff preparations. In this case, infarcts were 19.7% larger in CXCR2-/- than wild type hearts (P<0.05), revealing a novel CXCR2-mediated cardioprotective effect.
Conclusions CXCR2 exerts opposing effects on myocardial viability during ischemia-reperfusion with recruitment of damaging inflammatory cells predominant over direct tissue protection.
Key Words: ischemia reperfusion chemokines leukocytes
This article has been cited by other articles:
![]() |
W. A. Altemeier, X. Zhu, W. R. Berrington, J. M. Harlan, and W. C. Liles Fas (CD95) induces macrophage proinflammatory chemokine production via a MyD88-dependent, caspase-independent pathway J. Leukoc. Biol., September 1, 2007; 82(3): 721 - 728. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. W. Ashton, S. Mukherjee, F. Nagajyothi, H. Huang, V. L. Braunstein, M. S. Desruisseaux, S. M. Factor, L. Lopez, J. W. Berman, M. Wittner, et al. Thromboxane A2 is a key regulator of pathogenesis during Trypanosoma cruzi infection J. Exp. Med., April 16, 2007; 204(4): 929 - 940. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Zhai, X.-d. Shen, W. W. Hancock, F. Gao, B. Qiao, C. Lassman, J. A. Belperio, R. M. Strieter, R. W. Busuttil, and J. W. Kupiec-Weglinski CXCR3+CD4+ T Cells Mediate Innate Immune Function in the Pathophysiology of Liver Ischemia/Reperfusion Injury J. Immunol., May 15, 2006; 176(10): 6313 - 6322. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. L. Riddle, R. A. Schwartzman, M. Bond, and P. A. Insel Multi-Tasking RGS Proteins in the Heart: The Next Therapeutic Target? Circ. Res., March 4, 2005; 96(4): 401 - 411. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. A. Bursill, R. P. Choudhury, Z. Ali, D. R. Greaves, and K. M. Channon Broad-Spectrum CC-Chemokine Blockade by Gene Transfer Inhibits Macrophage Recruitment and Atherosclerotic Plaque Formation in Apolipoprotein E-Knockout Mice Circulation, October 19, 2004; 110(16): 2460 - 2466. [Abstract] [Full Text] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2003 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |