HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: fj.08-112201v1 22/10/3595    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Merched, A. J. Articles by Chan, L. PubMed PubMed Citation Articles by Merched, A. J. Articles by Chan, L.

Atherosclerosis: evidence for impairment of resolution of vascular inflammation governed by specific lipid mediators

Aksam J. Merched^*,1, Kerry Ko^*, Katherine H. Gotlinger, Charles N. Serhan and Lawrence Chan^*,

^* Department of Molecular and Cellular Biology and

Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Baylor College of Medicine, and St. Luke’s Episcopal Hospital, Houston, Texas, USA; and

Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA

¹ Correspondence: Department of Molecular and Cellular Biology, Baylor College of Medicine, 1 Baylor Plaza, N520.11, Houston, TX 77030, USA. E-mail: amerched{at}bcm.edu

Atherosclerosis is now recognized as an inflammatory disease involving the vascular wall. Recent results indicate that acute inflammation does not simply passively resolve as previously assumed but is actively terminated by a homeostatic process that is governed by specific lipid-derived mediators initiated by lipoxygenases. Experiments with animals and humans support a proinflammatory role for the 5-lipoxygenase system. In contrast, results from animal experiments show a range of responses with the 12/15-lipoxygenase pathways in atherosclerosis. To date, the only two clinical epidemiology human studies both support an antiatherogenic role for 12/15-lipoxygenase downstream actions. We tested the hypothesis that atherosclerosis results from a failure in the resolution of local inflammation by analyzing apolipoprotein E-deficient mice with 1) global leukocyte 12/15-lipoxygenase deficiency, 2) normal enzyme expression, or 3) macrophage-specific 12/15-lipoxygenase overexpression. Results from these indicate that 12/15-lipoxygenase expression protects mice against atherosclerosis via its role in the local biosynthesis of lipid mediators, including lipoxin A₄, resolvin D1, and protectin D1. These mediators exert potent agonist actions on macrophages and vascular endothelial cells that can control the magnitude of the local inflammatory response. Taken together, these findings suggest that a failure of local endogenous resolution mechanisms may underlie the unremitting inflammation that fuels atherosclerosis.—Merched, A. J., Ko, K., Gotlinger, K. H., Serhan, C. N. Chan, L. Atherosclerosis: evidence for impairment of resolution of vascular inflammation governed by specific lipid mediators.

Key Words: lipoxygenase • innate immunity