title: Peritoneal dialysis fluid induces p38-dependent inflammation in human mesothelial cells.
abstract: BACKGROUND
  Noninfectious upregulation of proinflammatory pathways in mesothelial cells may represent an integral part of their stress response upon exposure to peritoneal dialysis fluids (PDF).
  
  
  OBJECTIVE
  The aim of this study was to evaluate the role of the stress-inducible mitogen-activated protein kinase (MAPK) p38 in regulation of inflammatory and stress responses in mesothelial cells following in vitro exposure to PDF.
  
  
  METHODS
  Human peritoneal mesothelial cells were exposed to Dianeal PD4 or Physioneal (Baxter AG, Vienna, Austria) containing 1.36% glucose and then allowed to recover. Phosphorylation of p38, induction of heat shock protein-70 (HSP70), release of lactate dehydrogenase (LDH), secretion of interleukin (IL)-8, gene transcription, and mRNA stability were assessed with and without the MAPK p38 inhibitor SB203580.
  
  
  RESULTS
  Exposure to Dianeal resulted in phosphorylation of p38 within 30 minutes (309% of control, p < 0.05) and increased IL-8 release (370% of control, p < 0.05), HSP70 expression (151% of control, p < 0.05), and LDH release (180% of control, p < 0.05). Exposure to Physioneal resulted in attenuated changes in IL-8, HSP70, and LDH. Addition of the p38 inhibitor SB203580 to Dianeal resulted in dampened IL-8 release (-55%; p < 0.05) and basal HSP70 expression, and unchanged LDH release. Effects of p38 on IL-8 were at transcriptional, posttranscriptional, and translational levels.
  
  
  CONCLUSIONS
  These data confirm concordant p38-dependent upregulation of IL-8 and HSP70 following exposure to bioincompatible PDF. The MAPK p38 pathway therefore links proinflammatory processes and the cellular stress response in human peritoneal mesothelial cells.
authors.affiliation: Department of Pediatrics, Medical University, Vienna, Austria.
authors.forename: Andrea
authors.initials: A
authors.lastname: Riesenhuber
authors.forename: Klaus
authors.initials: K
authors.lastname: Kratochwill
authors.forename: Thorsten O
authors.initials: TO
authors.lastname: Bender
authors.forename: Regina
authors.initials: R
authors.lastname: Vargha
authors.forename: David C
authors.initials: DC
authors.lastname: Kasper
authors.forename: Rebecca
authors.initials: R
authors.lastname: Herzog
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Salzer
authors.forename: Christoph
authors.initials: C
authors.lastname: Aufricht
mesh_terms: D002478:Cells, Cultured; D015314:Dialysis Solutions / Q000009:adverse effects*; D004847:Epithelial Cells / Q000187:drug effects*; D006801:Humans; D007249:Inflammation / Q000139:chemically induced*; D010530:Peritoneal Dialysis; D048051:p38 Mitogen-Activated Protein Kinases / Q000187:drug effects* / Q000502:physiology*
chemical_list: D015314:Dialysis Solutions; D048051:p38 Mitogen-Activated Protein Kinases