期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2014
卷号：111
期号：46
页码：16526-16531
DOI：10.1073/pnas.1407123111
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceNeutrophil accumulation is fundamental to acute inflammation. In response to tissue injury, circulating neutrophil-platelet aggregates (N-PAs) form for secondary capture. Counterregulation of acute inflammatory processes by specialized proresolving mediators is essential to mitigate collateral injury to healthy bystander tissue. Here, we identified a biosynthetic route in human platelets for the proresolving mediator maresin 1 (MaR1) that is amplified during platelet-neutrophil interactions. In a self-resolving murine model of acute lung injury, N-PAs rapidly formed and a MaR1 counterregulatory circuit was engaged to restrain N-PAs and acute inflammation and restore homeostasis of the injured lung. Unregulated acute inflammation can lead to collateral tissue injury in vital organs, such as the lung during the acute respiratory distress syndrome. In response to tissue injury, circulating platelet-neutrophil aggregates form to augment neutrophil tissue entry. These early cellular events in acute inflammation are pivotal to timely resolution by mechanisms that remain to be elucidated. Here, we identified a previously undescribed biosynthetic route during human platelet-neutrophil interactions for the proresolving mediator maresin 1 (MaR1; 7R,14S-dihydroxy-docosa-4Z,8E,10E,12Z,16Z,19Z-hexaenoic acid). Docosahexaenoic acid was converted by platelet 12-lipoxygenase to 13S,14S-epoxy-maresin, which was further transformed by neutrophils to MaR1. In a murine model of acute respiratory distress syndrome, lipid mediator metabololipidomics uncovered MaR1 generation in vivo in a temporally regulated manner. Early MaR1 production was dependent on platelet-neutrophil interactions, and intravascular MaR1 was organ-protective, leading to decreased lung neutrophils, edema, tissue hypoxia, and prophlogistic mediators. Together, these findings identify a transcellular route for intravascular maresin 1 biosynthesis via platelet-neutrophil interactions that regulates the extent of lung inflammation.
