title: Aspirin-triggered lipoxin A4 and lipoxin A4 up-regulate transcriptional corepressor NAB1 in human neutrophils.
abstract: Aspirin-triggered 15-epi-lipoxin A4 (ATL) is an endogenous lipid mediator that mimics the actions of native lipoxin A4, a putative "stop signal" involved in regulating resolution of inflammation. A metabolically more stable analog of ATL, 15-epi-16-(para-fluoro)-phenoxy-lipoxin A4 analog (ATLa), inhibits neutrophil recruitment in vitro and in vivo and displays potent anti-inflammatory actions. ATLa binds with high affinity to the lipoxin A4 receptor, a G protein-coupled receptor on the surface of leukocytes. In this study, we used freshly isolated human neutrophils to examine ATLa's potential for initiating rapid nuclear responses. Using differential display reverse transcription polymerase chain reaction, we identified a subset of genes that was selectively up-regulated upon short exposure of polymorphonuclear leukocytes to ATLa but not to the chemoattractant leukotriene B4 or vehicle alone. We further investigated ATLa regulation of one of the genes, NAB1, a transcriptional corepressor identified previously as a glucocorticoid-responsive gene in hamster smooth muscle cells. Treatment of human neutrophils with pertussis toxin blocked ATLa up-regulation of NAB1. In addition, ATLa stimulated NAB1 gene expression in murine lung vascular smooth muscle in vivo. These findings provide evidence for rapid transcriptional induction of a cassette of genes via an ATLa-stimulated G protein-coupled receptor pathway that is potentially protective and overlaps with the anti-inflammatory glucocorticoid regulatory circuit.
authors.affiliation: Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: F H
authors.initials: FH
authors.lastname: Qiu
authors.forename: P R
authors.initials: PR
authors.lastname: Devchand
authors.forename: K
authors.initials: K
authors.lastname: Wada
authors.forename: C N
authors.initials: CN
authors.lastname: Serhan
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001241:Aspirin / Q000494:pharmacology*; D018076:DNA, Complementary / Q000235:genetics; D019204:GTP-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D007975:Leukotriene B4 / Q000494:pharmacology; D044045:Lipoxins; D008954:Models, Biological; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000502:physiology; D012097:Repressor Proteins / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014158:Transcription, Genetic / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D018076:DNA, Complementary; D006893:Hydroxyeicosatetraenoic Acids; D044045:Lipoxins; C094815:NAB1 protein, human; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D012097:Repressor Proteins; C040527:lipoxin A4; D007975:Leukotriene B4; D019204:GTP-Binding Proteins; D001241:Aspirin