8-11-14-eicosatrienoic-acid and Burns

Oxylipins modulate the behavior of immune cells in inflammation. Soluble epoxide hydrolase (sEH) converts anti-inflammatory epoxyeicosatrienoic acid (EET) to dihydroxyeicosatrienoic acid (DHET). An sEH-inhibitor, TPPU, has been demonstrated to ameliorate lipopolysaccharide (LPS)- and sepsis-induced inflammation via EETs. The immunomodulatory role of DHET is not well characterized. We hypothesized that TPPU dampens inflammation and that sEH-derived DHET alters neutrophil functionality in burn induced inflammation. Outbred mice were treated with vehicle, TPPU or 14,15-DHET and immediately subjected to either sham or dorsal scald 28% total body surface area burn injury. After 6 and 24 h, interleukin 6 (IL-6) serum levels and neutrophil activation were analyzed. For in vitro analyses, bone marrow derived neutrophil functionality and mRNA expression were examined. In vivo, 14,15-DHET and IL-6 serum concentrations were decreased after burn injury with TPPU administration. In vitro, 14,15-DHET impaired neutrophil chemotaxis, acidification, CXCR1/CXCR2 expression and reactive oxygen species (ROS) production, the latter independent from p38MAPK and PI3K signaling. We conclude that TPPU administration decreases DHET post-burn. Furthermore, DHET downregulates key neutrophil immune functions and mRNA expression. Altogether, these data reveal that TPPU not only increases anti-inflammatory and inflammation resolving EET levels, but also prevents potential impairment of neutrophils by DHET in trauma.

Topics: 8,11,14-Eicosatrienoic Acid; Animals; Anti-Inflammatory Agents; Burns; Cytokines; Epoxide Hydrolases; Female; Lipopolysaccharides; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; NADPH Oxidases; Neutrophils; p38 Mitogen-Activated Protein Kinases; Phagocytosis; Phenylurea Compounds; Phosphatidylinositol 3-Kinases; Piperidines; Reactive Oxygen Species; Receptors, Chemokine; Respiratory Burst; Transcription, Genetic

Topics: 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; 8,11,14-Eicosatrienoic Acid; Animals; Burns; Contact Lenses; Cytochrome P-450 Enzyme System; Disease Models, Animal; Eicosanoids; Eye Injuries; Inflammation; Neovascularization, Physiologic; Rabbits; Wound Healing