15-Epi-lipoxin A4 Inhibits Myeloperoxidase Signaling and Enhances Resolution of Acute Lung Injury

作者：Driss El Kebir, Levente József, Wanling Pan, Lili Wang, Nicos A. Petasis, Charles Nicholas Serhan, János G. Filep · 发表于：American Journal of Respiratory and Critical Care Medicine · 年份：2009 · DOI：10.1164/rccm.200810-1601oc · 被引用次数：203 · 研究领域：Neutrophil, Myeloperoxidase and Oxidative Mechanisms、Immune Response and Inflammation、Cell Adhesion Molecules Research

RATIONALE: Apoptosis is essential for removal of neutrophils from inflamed tissues and efficient resolution of inflammation. Myeloperoxidase (MPO), abundantly expressed in neutrophils, not only generates cytotoxic oxidants but also signals through the beta(2) integrin Mac-1 to rescue neutrophils from constitutive apoptosis, thereby prolonging inflammation. OBJECTIVES: Because aspirin-triggered 15-epi-lipoxin A(4) (15-epi-LXA(4)) modulates Mac-1 expression, we investigated the impact of 15-epi-LXA(4) on MPO suppression of neutrophil apoptosis and MPO-mediated neutrophil-dependent acute lung injury. METHODS: Human neutrophils were cultured with MPO with or without 15-epi-LXA(4) to investigate development of apoptosis. Acute lung injury was produced by intratracheal injection of carrageenan plus MPO or intraperitoneal injection of live Escherichia coli in mice, and the animals were treated with 15-epi-LXA(4) at the peak of inflammation. MEASUREMENTS AND MAIN RESULTS: 15-Epi-LXA(4) through down-regulation of Mac-1 expression promoted apoptosis of human neutrophils by attenuating MPO-induced activation of extracellular signal-regulated kinase and Akt-mediated phosphorylation of Bad and by reducing expression of the antiapoptotic protein Mcl-1, thereby aggravating mitochondrial dysfunction. The proapoptotic effect of 15-epi-LXA(4) was dominant over MPO-mediated effects even when it was added at 4 hours post MPO. In mice, treatment with 15-epi-LXA(4) accelerated the resolution of es...