title: Peritoneal dialysis fluids can alter HSP expression in human peritoneal mesothelial cells.
abstract: BACKGROUND
  Acute exposure of mesothelial cells to peritoneal dialysis fluid (PDF) has been shown not only to result in injury but also to induce cytoprotective heat shock proteins (HSP). The aim of the present study was to evaluate the expression of HSP in a more chronic in vitro PDF exposure system, searching for a role of glucose degradation products (GDP).
  
  
  METHODS
  Human peritoneal mesothelial cells (HPMC) were chronically incubated in filter- or heat-sterilized PDF (mixed 1:1 with cell culture medium), or in control cell culture medium. After incubation periods of 1, 3 and 10 days, cell extract was assessed for Ezrin, Hsp27 and Hsp72, and supernatant for IL-6 and IL-8. After 24-h exposure to the GDP 3.4-di-deoxyglucosone-3-ene (3.4-DGE), HPMC were assessed for expression of Hsp27 and Hsp72, and for release of LDH, IL-6 and IL-8.
  
  
  RESULTS
  In vitro PDF exposure for more than 1 day resulted in reduced cell mass, lower expression of the epithelial marker Ezrin and depressed cellular levels of both HSP, associated with increased IL-6 and IL-8 release. These effects occurred earlier and stronger with heat-sterilized than with filter-sterilized PDF. Exposure of HPMC to 3.4-DGE resulted in suppression of HSP, and increased release of LDH, IL-6 and IL-8.
  
  
  CONCLUSIONS
  Our data show that GDP (dys)regulate the mesothelial cell stress response. This was associated with reduced cell mass, loss of the epithelial phenotype and sterile cellular inflammation following extended exposure to heat-sterilized PDF. Toxic effects of PDF might thus be extended to reduced mesothelial cell stress responses.
authors: Department of Nephrology and Medical Intensive Care, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum, Berlin, Germany.
authors: Thorsten O
authors: TO
authors: Bender
authors: Michael
authors: M
authors: Böhm
authors: Klaus
authors: K
authors: Kratochwill
authors: Regina
authors: R
authors: Vargha
authors: Andrea
authors: A
authors: Riesenhuber
authors: Janusz
authors: J
authors: Witowski
authors: Achim
authors: A
authors: Jörres
authors: Anders
authors: A
authors: Wieslander
authors: Christoph
authors: C
authors: Aufricht
mesh_terms: D001202:Ascitic Fluid / Q000378:metabolism*; D015153:Blotting, Western; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins / Q000378:metabolism; D015314:Dialysis Solutions / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D004848:Epithelium / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D055551:HSP27 Heat-Shock Proteins / Q000378:metabolism*; D050884:HSP72 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D010530:Peritoneal Dialysis; D000099149:Ezrin
chemical_list: D003598:Cytoskeletal Proteins; D015314:Dialysis Solutions; D005947:Glucose; D055551:HSP27 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D015850:Interleukin-6; D016209:Interleukin-8; D000099149:Ezrin