title: SAHA Suppresses Peritoneal Fibrosis in Mice.
abstract: OBJECTIVE
  Long-term peritoneal dialysis causes peritoneal fibrosis in submesothelial areas. However, the mechanism of peritoneal fibrosis is unclear. Epigenetics is the mechanism to induce heritable changes without any changes in DNA sequences. Among epigenetic modifications, histone acetylation leads to the transcriptional activation of genes. Recent studies indicate that histone acetylation is involved in the progression of fibrosis. Therefore, we examined the effect of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, on the progression of peritoneal fibrosis in mice.
  
  
  METHODS
  Peritoneal fibrosis was induced by the injection of chlorhexidine gluconate (CG) into the peritoneal cavity of mice every other day for 3 weeks. SAHA, or a dimethylsulfoxide and saline vehicle, was administered subcutaneously every day from the start of the CG injections for 3 weeks. Morphologic peritoneal changes were assessed by Masson's trichrome staining, and fibrosis-associated factors were assessed by immunohistochemistry.
  
  
  RESULTS
  In CG-injected mice, a marked thickening of the submesothelial compact zone was observed. In contrast, the administration of SAHA suppressed the progression of submesothelial thickening and type III collagen accumulation in CG-injected mice. The numbers of fibroblast-specific protein-1-positive cells and α-smooth muscle actin α-positive cells were significantly decreased in the CG + SAHA group compared to that of the CG group. The level of histone acetylation was reduced in the peritoneum of the CG group, whereas it was increased in the CG + SAHA group.
  
  
  CONCLUSIONS
  Our results indicate that SAHA can suppress peritoneal thickening and fibrosis in mice through up-regulation of histone acetylation. These results suggest that SAHA may have therapeutic potential for treating peritoneal fibrosis.
authors.affiliation: Second Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Io
authors.affiliation: Second Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Nishino
authors.affiliation: Second Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Obata
authors.affiliation: Second Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Mineaki
authors.initials: M
authors.lastname: Kitamura
authors.affiliation: Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Koji
authors.affiliation: Second Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kohno
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D018450:Disease Progression; D005462:Fluorine Radioisotopes; D056572:Histone Deacetylase Inhibitors / Q000008:administration & dosage; D006877:Hydroxamic Acids / Q000008:administration & dosage*; D007279:Injections, Subcutaneous; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010530:Peritoneal Dialysis / Q000009:adverse effects*; D056627:Peritoneal Fibrosis / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D000077337:Vorinostat
chemical_list: D005462:Fluorine Radioisotopes; D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; D000077337:Vorinostat
keywords: SAHA; Suberoylanilide hydroxamic acid; chlorhexidine gluconate; histone deacetylase inhibitor; peritoneal fibrosis