title: Oxidative stress induces unfolding protein response and inflammation in nasal polyposis.
abstract: BACKGROUND
  Nasal polyposis, a chronic inflammatory disease affecting the upper airways, is a valuable and accessible model to investigate the mechanisms underlying chronic inflammation. The main objective of this study was to investigate a potential involvement of the unfolded protein response (UPR) in the context of oxidative stress and inflammation in nasal epithelial cells from nasal polyps (NP).
  
  
  METHODS
  Epithelial cells from NP (n = 20) and normal mucosa (Controls, n = 15) in primary culture were analyzed by global proteomic approach and cell biology techniques for the glucose-regulated protein 78 (GRP78), the spliced X-box-binding protein 1 (sXBP-1), the glucose-regulated protein 94 (GRP94), and the calreticulin (immunoblot, mass spectrometry, immunocytochemistry).
  
  
  RESULTS
  Proteomics analysis of human nasal epithelial cells in culture revealed the activation of the unfolded protein response in NP. Systematic cell biology and biochemical analysis of two markers (GRP78, sXBP-1) in the presence and absence of oxidative stress in NP showed a susceptibility of the unfolded protein response to oxidative stress compared to controls at least partially linked to an abnormal redox state of the protein disulfide-isomerase 4. This unfolded protein response was correlated with mitochondrial depolarization and secretion of interleukin 8 (IL-8) and leukotriene B4 (LTB4) and was prevented by mitochondrial antioxidant.
  
  
  CONCLUSIONS
  We show the existence of UPR in nasal epithelial cells that is linked to oxidative stress leading to IL-8 and LTB4 secretions. These mechanisms may participate in chronic inflammation in nasal polyposis.
authors.affiliation: INSERM, Créteil, France.
authors.forename: L
authors.initials: L
authors.lastname: Jeanson
authors.forename: M
authors.initials: M
authors.lastname: Kelly
authors.forename: A
authors.initials: A
authors.lastname: Coste
authors.forename: I C
authors.initials: IC
authors.lastname: Guerrera
authors.forename: J
authors.initials: J
authors.lastname: Fritsch
authors.forename: T
authors.initials: T
authors.lastname: Nguyen-Khoa
authors.forename: M
authors.initials: M
authors.lastname: Baudouin-Legros
authors.forename: J-F
authors.initials: JF
authors.lastname: Papon
authors.forename: P
authors.initials: P
authors.lastname: Zadigue
authors.forename: V
authors.initials: V
authors.lastname: Prulière-Escabasse
authors.forename: S
authors.initials: S
authors.lastname: Amselem
authors.forename: E
authors.initials: E
authors.lastname: Escudier
authors.forename: A
authors.initials: A
authors.lastname: Edelman
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D002478:Cells, Cultured; D000091342:Endoplasmic Reticulum Chaperone BiP; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D005786:Gene Expression Regulation; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D016209:Interleukin-8 / Q000378:metabolism; D007975:Leukotriene B4 / Q000378:metabolism; D009297:Nasal Mucosa / Q000166:cytology / Q000276:immunology*; D009298:Nasal Polyps / Q000276:immunology / Q000503:physiopathology*; D018384:Oxidative Stress; D020543:Proteome; D040901:Proteomics; D056811:Unfolded Protein Response
chemical_list: D000975:Antioxidants; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D016209:Interleukin-8; D020543:Proteome; D007975:Leukotriene B4