title: Mitomycin C treatment significantly reduces central damage of islets in culture.
abstract: OBJECTIVE
  We recently reported that mitomycin C (MMC) treatment and subsequent culture of islets significantly prolongs graft survival in allotransplantation and xenotransplantation models. The present study was performed to determine the changes in morphology and signal transduction in pancreatic islets after MMC treatment.
  
  
  METHODS
  Freshly isolated rat islets were treated with 10 μg/mL MMC for 30 minutes and then cultured for up to 3 days. The samples were processed for immunohistologic studies and electron microscopic examination at various times after treatment. A DNA fragmentation assay was performed to detect apoptotic cell death. Western blotting was performed to determine the effects of MMC on signal transduction.
  
  
  RESULTS
  As early as 4 hours after culture, the islets showed central damage; most cells were necrotic and stained with anti-high mobility group box 1 antibody, and a few were apoptotic. The ratio of the damaged area to the whole area was significantly decreased after MMC treatment. Western blotting showed that MMC treatment increased the levels of activated forms of p53 and p21, whereas levels of the activated forms of Akt and caspase-3 were unchanged.
  
  
  CONCLUSIONS
  Mitomycin C treatment protects islets from the progression of central damage during culture. The p53-p21 pathway might be involved in these effects.
  
  
  BACKGROUND
  MMC - mitomycin C, HMGB1 - high mobility group box 1.
authors.affiliation: Department of Surgery, Fukushima Medical University, Fukushima, Japan.
authors.forename: Takaharu
authors.initials: T
authors.lastname: Saito
authors.forename: Takuro
authors.initials: T
authors.lastname: Saito
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sato
authors.forename: Kazuya
authors.initials: K
authors.lastname: Ise
authors.forename: Takayuki
authors.initials: T
authors.lastname: Anazawa
authors.forename: Ikuro
authors.initials: I
authors.lastname: Oshibe
authors.forename: Junichiro
authors.initials: J
authors.lastname: Haga
authors.forename: Masaya
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Waguri
authors.forename: Mitsukazu
authors.initials: M
authors.lastname: Gotoh
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D019610:Cytoprotection; D005934:Glucagon / Q000378:metabolism; D024243:HMGB1 Protein / Q000378:metabolism; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D046529:Microscopy, Electron, Transmission; D016685:Mitomycin / Q000494:pharmacology*; D009336:Necrosis; D020011:Protective Agents / Q000494:pharmacology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D046509:Tissue Culture Techniques; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: C493958:Cdkn1a protein, rat; D050759:Cyclin-Dependent Kinase Inhibitor p21; D024243:HMGB1 Protein; C104200:Hbp1 protein, rat; D007328:Insulin; D020011:Protective Agents; D016159:Tumor Suppressor Protein p53; D016685:Mitomycin; D005934:Glucagon; D051057:Proto-Oncogene Proteins c-akt; C505410:Casp3 protein, rat; D053148:Caspase 3