Title: Contributions of the three CYP1 monooxygenases to pro-inflammatory and inflammation-resolution lipid mediator pathways.
Authors: Divanovic, Senad; Dalli, Jesmond; Jorge-Nebert, Lucia F; Flick, Leah M; Gálvez-Peralta, Marina; Boespflug, Nicholas D; Stankiewicz, Traci E; Fitzgerald, Jonathan M; Somarathna, Maheshika; Karp, Christopher L; Serhan, Charles N; Nebert, Daniel W
Published In J Immunol, (2013 Sep 15)
Abstract: All three cytochrome P450 1 (CYP1) monooxygenases are believed to participate in lipid mediator biosynthesis and/or their local inactivation; however, distinct metabolic steps are unknown. We used multiple-reaction monitoring and liquid chromatography-UV coupled with tandem mass spectrometry-based lipid-mediator metabololipidomics to identify and quantify three lipid-mediator metabolomes in basal peritoneal and zymosan-stimulated inflammatory exudates, comparing Cyp1a1/1a2/1b1(⁻/⁻) C57BL/6J-background triple-knockout mice with C57BL/6J wild-type mice. Significant differences between untreated triple-knockout and wild-type mice were not found for peritoneal cell number or type or for basal CYP1 activities involving 11 identified metabolic steps. Following zymosan-initiated inflammation, 18 lipid mediators were identified, including members of the eicosanoids and specialized proresolving mediators (i.e., resolvins and protectins). Compared with wild-type mice, Cyp1 triple-knockout mice exhibited increased neutrophil recruitment in zymosan-treated peritoneal exudates. Zymosan stimulation was associated with eight statistically significantly altered metabolic steps: increased arachidonic acid-derived leukotriene B₄ (LTB₄) and decreased 5S-hydroxyeicosatetraenoic acid; decreased docosahexaenoic acid-derived neuroprotectin D1/protectin D1, 17S-hydroxydocosahexaenoic acid, and 14S-hydroxydocosahexaenoic acid; and decreased eicosapentaenoic acid-derived 18R-hydroxyeicosapentaenoic acid (HEPE), 15S-HEPE, and 12S-HEPE. In neutrophils analyzed ex vivo, elevated LTB₄ levels were shown to parallel increased neutrophil numbers, and 20-hydroxy-LTB₄ formation was found to be deficient in Cyp1 triple-knockout mice. Together, these results demonstrate novel contributions of CYP1 enzymes to the local metabolite profile of lipid mediators that regulate neutrophilic inflammation.
PubMed ID: 23956430
MeSH Terms: Animals; Cytochrome P-450 Enzyme System/immunology; Cytochrome P-450 Enzyme System/metabolism*; Humans; Inflammation Mediators/immunology; Inflammation Mediators/metabolism*; Inflammation/immunology; Inflammation/metabolism*; Lipids/immunology; Metabolome; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils/immunology; Neutrophils/metabolism; Signal Transduction/immunology*