title: ERK/Egr-1 signaling pathway is involved in CysLT2 receptor-mediated IL-8 production in HEK293 cells.
abstract: The CysLT2 receptor is involved in myocardial ischemia/reperfusion injury, differentiation of colorectal cancers, bleomycin-induced pulmonary inflammation and fibrosis. However, the signal transduction of cysteinyl leukotriene receptor 2 (CysLT2) in inflammatory responses remains to be clarified. In HEK293 cells stably expressing hCysLT1, hCysLT2 and rGPR17, we determined the signaling pathways for interleukin-8 (IL-8) production after CysLT2 receptor activation. HEK293 cells were stably transfected with the recombinant plasmids of pcDNA3.1(+)-hCysLT1, pcDNA3.1(+)-hCysLT2 and pcDNA3.1-rGPR17. Leukotriene C4 (LTC4) and LTD4 were used as the agonists to induce IL-8 production and the related changes in signal molecules. We found that LTC4 and LTD4 significantly induced IL-8 promoter activation in the HEK293 cells stably expressing hCysLT2, but not in those expressing hCysLT1 and rGPR17. In hCysLT2-HEK293 cells, LTC4 induced elevation of intracellular calcium, ERK1/2 phosphorylation and Egr-1 expression, and stimulated IL-8 expression and release. These responses were blocked by the selective CysLT2 receptor antagonist HAMI3379. The ERK1/2 inhibitor U0126 inhibited Egr-1 and IL-8 expression as well as IL-8 release, but the JNK and p38 inhibitors did not have the inhibitory effects. Down-regulation of Egr-1 by RNA interference with its siRNA inhibited the LTC4-induced IL-8 expression and release. In conclusion, these findings indicate the ERK-Egr-1 pathway of CysLT2 receptors mediates IL-8 production induced by the pro-inflammatory mediators LTC4 and LTD4.
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China; Department of Pharmacy, Second Affiliated Hospital (Binjiang Branch), School of Medicine, Zhejiang University, 1511 Jianghong Road, Hangzhou 310052, PR China.
authors.forename: Kana
authors.initials: K
authors.lastname: Lin
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China. Electronic address: fshfbzxhq@zju.edu.cn.
authors.forename: Sanhua
authors.initials: S
authors.lastname: Fang
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China; Department of Pharmacy, Second Affiliated Hospital (Binjiang Branch), School of Medicine, Zhejiang University, 1511 Jianghong Road, Hangzhou 310052, PR China.
authors.forename: Beilei
authors.initials: B
authors.lastname: Cai
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China.
authors.forename: Xiayan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China.
authors.forename: Yunbi
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Pharmacology and Institute of Neuroscience, School of Medicine, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China.
authors.forename: Erqing
authors.initials: E
authors.lastname: Wei
mesh_terms: D002070:Butadienes / Q000494:pharmacology; D003509:Cyclohexanecarboxylic Acids / Q000494:pharmacology; D051766:Early Growth Response Protein 1 / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D057809:HEK293 Cells; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000378:metabolism; D017997:Leukotriene C4 / Q000378:metabolism; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors; D009570:Nitriles / Q000494:pharmacology; D010795:Phthalic Acids / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D018077:Receptors, Leukotriene / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C549635:3-(((3-carboxycyclohexyl)amino)carbonyl)-4-(3-(4-(4-(cyclohexyloxy)butoxy)phenyl)propoxy)benzoic acid; D002070:Butadienes; D003509:Cyclohexanecarboxylic Acids; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; D004791:Enzyme Inhibitors; C121670:GPR17 protein, human; D016209:Interleukin-8; D009570:Nitriles; D010795:Phthalic Acids; D043562:Receptors, G-Protein-Coupled; D018077:Receptors, Leukotriene; D014157:Transcription Factors; C113580:U 0126; D017997:Leukotriene C4; C412375:cysteinyl leukotriene receptor 2; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; C083169:leukotriene D4 receptor
keywords: Cysteinyl leukotriene receptor 2; Early growth response-1; Extracellular signal-regulated kinase; Interleukin-8; Signal transduction