title: Cilostazol inhibits HMGB1 release in LPS-activated RAW 264.7 cells and increases the survival of septic mice.
abstract: BACKGROUND
  Inflammation and coagulation play important roles in the pathogenesis of sepsis. Anticoagulants with anti-inflammatory action draw attention as therapeutic agent in sepsis.
  
  
  OBJECTIVE
  Whether cilostazol (6-[4-(1-cyclohexyl-1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2-(1H)-quinolinone), anticoagulant, protects mice against sepsis and underlying mechanism(s) were investigated.
  
  
  METHODS
  Induction of heme oxygenase (HO)-1 protein, phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) luciferase activity, and release of high mobility group box 1 (HMGB1) were analyzed using signal inhibitors and transfection techniques. Survival and organ damage were compared in septic mice with and without cilostazol.
  
  
  RESULTS
  In RAW264.7 cells, cilostazol increased phosphorylation of AMPK which was followed by HO-1 induction. Lipopolysaccharide (LPS)-activated HMGB1 release was reduced by cilostazol which was reversed by both SB203580 and silencing of HO-1 or AMPK RNA. Interestingly, silencing AMPK reduced HO-1 expression, whereas silencing HO-1 did not affect p-AMPK by cilostazol. Both compound C and zinc protoporphyrin IX (ZnPPIX) antagonized inhibitory effect of HMGB1 by cilostazol. Cilostazol inhibited NF-κB luciferase activity which was antagonized by SB203580. Finally, the administration of cilostazol increased the survival of endotoxemic mice but failed to do so when co-treated with rHMGB1. Cilostazol reduced circulating HMGB1, plasminogen activator inhibitor-1 (PAI-1) levels, organ damages and protein expression of PAI-1 in lung tissues of CLP-septic mice, which were antagonized by ZnPPIX.
  
  
  CONCLUSIONS
  These findings suggest that HMGB1 can be a target molecule of cilostazol by 1) AMPK activation, and 2) induction of HO-1 by p38 MAPK and AMPK. Therefore, cilostazol may be useful for treatment of sepsis.
authors.affiliation: Department of Pharmacology, School of Medicine Gyeongsang National University and Institute of Health Sciences, Jinju 660-751, Korea. Electronic address: kcchang@gnu.kr.
authors.forename: Ki Churl
authors.initials: KC
authors.lastname: Chang
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000008:administration & dosage; D000077407:Cilostazol; D004305:Dose-Response Relationship, Drug; D024243:HMGB1 Protein / Q000276:immunology*; D051547:Heme Oxygenase-1 / Q000276:immunology*; D008070:Lipopolysaccharides; D008565:Membrane Proteins / Q000276:immunology*; D051379:Mice; D000067996:RAW 264.7 Cells; D018805:Sepsis / Q000139:chemically induced / Q000188:drug therapy* / Q000276:immunology*; D058258:Serpin E2 / Q000276:immunology*; D015996:Survival Rate; D013777:Tetrazoles / Q000008:administration & dosage*; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D024243:HMGB1 Protein; C582808:HMGB1 protein, mouse; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D058258:Serpin E2; C511869:Serpine2 protein, mouse; D013777:Tetrazoles; D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse; D000077407:Cilostazol
keywords: AMPK; Cilostazol; HMGB1; HO-1; Sepsis