title: Leukotriene D4 up-regulates furin expression through CysLT1 receptor signaling.
abstract: Leukotriene (LT)D(4) is suggested to play a role in airway remodeling, which is characterized by fibrogenesis and airway smooth muscle cell hyperplasia. In this study, we investigated the effects of LTD(4) on the expression of furin, a proprotein convertase involved in the maturation/activation of several substrates implicated in the remodeling processes. HEK293 cells stably transfected with the CysLT1 receptor were used to study the transcriptional regulation of furin by LTD(4). Stimulation of the cells with LTD(4) resulted in a time- and concentration-dependent induction of furin mRNA and protein expression. The study of furin gene (fur) promoters P1, P1A, and P1B revealed a selective transactivation of the P1 promoter by LTD(4). Mutations in the activator protein (AP)-1-binding element of the P1 promoter resulted in the partial loss of transactivation by LTD(4). Binding of AP-1 transcription factor to fur P1 promoter after stimulation with LTD(4) was demonstrated by electrophoretic mobility shift assay, and supershift assays indicated the formation of c-Jun/c-Fos complexes. LTD(4) induced the maturation of the furin substrates membrane-type 1 matrix metalloproteinase and transforming growth factor-beta1, which was inhibited by the furin inhibitor alpha1-PDX. Finally, LTD(4) induced furin gene expression in monocytic THP-1 cells, which was abrogated using a selective CysLT1 receptor antagonist and inhibitors of the mitogen-activated protein kinases MEK-1, p38, and JunK. Our data show for the first time that LTD(4), via the CysLT1 receptor, can transcriptionally activate furin production with consequent maturation of furin substrates relevant to airway remodeling. These findings suggest that CysLT1 is involved in remodeling processes through modulation of furin transcription.
authors.affiliation: Immunology Division, Department of Pediatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Thompson
authors.forename: Stéphanie
authors.initials: S
authors.lastname: McMahon
authors.forename: Ynuk
authors.initials: Y
authors.lastname: Bossé
authors.forename: Claire M
authors.initials: CM
authors.lastname: Dubois
authors.forename: Jana
authors.initials: J
authors.lastname: Stankova
authors.forename: Marek
authors.initials: M
authors.lastname: Rola-Pleszczynski
mesh_terms: D002460:Cell Line; D045683:Furin / Q000096:biosynthesis*; D006801:Humans; D017998:Leukotriene D4 / Q000494:pharmacology* / Q000502:physiology; D053511:Matrix Metalloproteinase 14 / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D011401:Promoter Regions, Genetic; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D018077:Receptors, Leukotriene / Q000502:physiology*; D015398:Signal Transduction; D015533:Transcriptional Activation; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D018077:Receptors, Leukotriene; D053773:Transforming Growth Factor beta1; D017998:Leukotriene D4; D020928:Mitogen-Activated Protein Kinases; D045683:Furin; D053511:Matrix Metalloproteinase 14; C083169:leukotriene D4 receptor