title: Reduced macrophage selenoprotein expression alters oxidized lipid metabolite biosynthesis from arachidonic and linoleic acid.
abstract: Uncontrolled inflammation is an underlying etiology for multiple diseases and macrophages orchestrate inflammation largely through the production of oxidized fatty acids known as oxylipids. Previous studies showed that selenium (Se) status altered the expression of oxylipids and magnitude of inflammatory responses. Although selenoproteins are thought to mediate many of the biological effects of Se, the direct effect of selenoproteins on the production of oxylipids is unknown. Therefore, the role of decreased selenoprotein activity in modulating the production of biologically active oxylipids from macrophages was investigated. Thioglycollate-elicited peritoneal macrophages were collected from wild-type and myeloid-cell-specific selenoprotein knockout mice to analyze oxylipid production by liquid chromatography/mass spectrometry as well as oxylipid biosynthetic enzyme and inflammatory marker gene expression by quantitative real-time polymerase chain reaction. Decreased selenoprotein activity resulted in the accumulation of reactive oxygen species, enhanced cyclooxygenase and lipoxygenase expression and decreased oxylipids with known anti-inflammatory properties such as arachidonic acid-derived lipoxin A₄ (LXA₄) and linoleic acid-derived 9-​oxo-octadecadienoic acid (9-oxoODE). Treating RAW 264.7 macrophages with LXA₄ or 9-oxoODE diminished oxidant-induced macrophage inflammatory response as indicated by decreased production of TNFα. The results show for the first time that selenoproteins are important for the balanced biosynthesis of pro- and anti-inflammatory oxylipids during inflammation. A better understanding of the Se-dependent control mechanisms governing oxylipid biosynthesis may uncover nutritional intervention strategies to counteract the harmful effects of uncontrolled inflammation due to oxylipids.
authors.affiliation: College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Mattmiller
authors.affiliation: Molecular Biology of Selenium Section, Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Carlson
authors.affiliation: College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Jeff C
authors.initials: JC
authors.lastname: Gandy
authors.affiliation: College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA. Electronic address: Sordillo@msu.edu.
authors.forename: Lorraine M
authors.initials: LM
authors.lastname: Sordillo
mesh_terms: D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D002461:Cell Line, Transformed; D003433:Crosses, Genetic; D015536:Down-Regulation; D018836:Inflammation Mediators / Q000378:metabolism; D019787:Linoleic Acid / Q000378:metabolism*; D008042:Linolenic Acids / Q000378:metabolism; D015227:Lipid Peroxidation; D008054:Lipid Peroxides / Q000378:metabolism*; D044045:Lipoxins / Q000378:metabolism; D058945:Lipoxygenases / Q000235:genetics / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D018384:Oxidative Stress; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism; D051140:Selenoproteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D018836:Inflammation Mediators; D008042:Linolenic Acids; D008054:Lipid Peroxides; D044045:Lipoxins; D051140:Selenoproteins; C040527:lipoxin A4; D016718:Arachidonic Acid; C062143:9-oxo-10,12-octadecadienoic acid; D019787:Linoleic Acid; D058945:Lipoxygenases; D011451:Prostaglandin-Endoperoxide Synthases
keywords: Eicosanoids; Macrophage; Oxylipids; Selenium; Selenoproteins