title: Sphingosine 1-phosphate regulates IL-8 expression and secretion via S1PR1 and S1PR2 receptors-mediated signaling in extravillous trophoblast derived HTR-8/SVneo cells.
abstract: BACKGROUND
  Both villous and extravillous trophoblast (EVT) cells produce a wide range of cytokines and also respond to them in autocrine and paracrine manner. Deregulation of cytokine secretion may lead to various pathologic conditions including preeclampsia. IL-8, a pro-inflammatory cytokine, regulates various cellular functions such as neutrophil trafficking, cell adhesion, tumor growth and has a role in placental development. IL-8 also promotes trophoblast cell migration and invasion, and stimulates the secretion of progesterone. The induction and mechanism of IL-8 secretion by EVT is still unknown.
  
  
  METHODS
  IL-8 mRNA expression and secretion was determined using real-time PCR and ELISA respectively. To identify the mechanism of IL-8 expression and secretion, selective antagonists and agonist of S1P receptor subtypes, Rac1 and Rho-kinase inhibitors were used.
  
  
  RESULTS
  We found that S1P induces IL-8 gene expression and protein secretion in EVT derived HTR-8/SVneo cells but not in BeWo cells. SEW2781, the selective agonist of S1PR(1), induced IL-8 gene expression but not protein secretion. The specific S1PR(2) inhibitor JTE-013 could drastically inhibit IL-8 secretion. Furthermore, pre-treatment of cells with the selective S1PR(1)/S1PR(3) antagonist VPC23019 inhibited IL-8 secretion by ∼45%. Selective Rho-kinase inhibitor Y27632 and Rac1 inhibitor NSC23766 could block IL-8 secretion in these cells.
  
  
  CONCLUSIONS
  In this study, we could show for the first time that S1P induces IL-8 mRNA expression and protein secretion in EVT cell line. S1P-induced IL-8 gene expression is mainly regulated via S1PR(1) and its secretion is regulated through S1PR(2) receptor subtype. Rho GTPases signaling is essential for S1P-induced IL-8 secretion.
authors: Department of Obstetrics and Gynecology, University of Greifswald, Ferdinand-Sauerbruchstrasse, D-17489, Greifswald, Germany; Department of Internal Medicine II, Division of Translational Oncology, University Hospital of Würzburg, Versbacher Str. 5, D-97078, Würzburg, Germany.
authors: Daniela
authors: D
authors: Brünnert
authors: Department of Obstetrics and Gynecology, University of Greifswald, Ferdinand-Sauerbruchstrasse, D-17489, Greifswald, Germany.
authors: Svea
authors: S
authors: Piccenini
authors: Department of Obstetrics and Gynecology, University of Greifswald, Ferdinand-Sauerbruchstrasse, D-17489, Greifswald, Germany.
authors: Jens
authors: J
authors: Ehrhardt
authors: Department of Obstetrics and Gynecology, University of Greifswald, Ferdinand-Sauerbruchstrasse, D-17489, Greifswald, Germany.
authors: Marek
authors: M
authors: Zygmunt
authors: Department of Obstetrics and Gynecology, University of Greifswald, Ferdinand-Sauerbruchstrasse, D-17489, Greifswald, Germany; Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Bandar Sindri, Kishangarh, Rajasthan, 305 801, India. Electronic address: Pankaj_bio@curaj.ac.in.
authors: Pankaj
authors: P
authors: Goyal
mesh_terms: D002460:Cell Line; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism*; D008246:Lysophospholipids / Q000502:physiology*; D049349:Receptors, Lysosphingolipid / Q000378:metabolism*; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000502:physiology; D000081025:Sphingosine-1-Phosphate Receptors; D014327:Trophoblasts / Q000378:metabolism*; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D016209:Interleukin-8; D008246:Lysophospholipids; D049349:Receptors, Lysosphingolipid; C477362:S1PR1 protein, human; C477522:S1PR2 protein, human; D000081025:Sphingosine-1-Phosphate Receptors; C060506:sphingosine 1-phosphate; D020741:rho GTP-Binding Proteins; D013110:Sphingosine
keywords: Cytokine secretion; Extravillous trophoblast; HTR-8/SVneo cells; IL-8; Placenta; S1P