Contributions of the three CYP1 monooxygenases to pro-inflammatory and inflammation-resolution lipid mediator pathways

J Immunol. 2013 Sep 15;191(6):3347-57. doi: 10.4049/jimmunol.1300699. Epub 2013 Aug 16.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cytochrome P-450 Enzyme System / immunology
  • Cytochrome P-450 Enzyme System / metabolism*
  • Humans
  • Inflammation / immunology
  • Inflammation / metabolism*
  • Inflammation Mediators / immunology
  • Inflammation Mediators / metabolism*
  • Lipids / immunology
  • Metabolome
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Neutrophils / immunology
  • Neutrophils / metabolism
  • Signal Transduction / immunology*

Substances

  • Inflammation Mediators
  • Lipids
  • Cytochrome P-450 Enzyme System