title: Singlet oxygen energy illumination during moderate cold ischemia prolongs the survival of concordant hamster xeno-heart transplants.
abstract: BACKGROUND
  Singlet oxygen energy (SOE) is a potent inhibitor of reactive oxygen species (ROS) in vitro and in vivo in certain dose ranges and can improve the levels of high-energy phosphates (HEP) in concordant hamster xeno-heart transplants. Some data indicate that a certain degree of cold ischemia (CI) might be beneficial to xenotransplants. We investigated if SOE illumination of hamster xeno-hearts during moderate cold ischemia (CI) improved graft survival.
  
  
  METHODS
  Eighteen hearts from Golden Syrian hamsters (70 to 80 g) were subjected to 8 hours of CI in cold (+4 degrees C) saline solution (NaCL, 0.9%) before heterotopic cervical transplantation to Lewis rats (220 g). Among the treatment group (n = 8), SOE was produced by illuminating the hearts for 10 minutes every 30 minutes with photons at lambda 634 nm with the Oxylight equipment. Graft function was evaluated every 6 hours after transplantation with digital exam until cessation of heart beats.
  
  
  RESULTS
  The graft survival of SOE-illuminated ischemic hamster xenografts was 2.34 +/- 0.56 versus 1.15 +/- 0.37 days in the control group (P < .05). All hearts displayed immediate graft function versus 70% in the controls (NS).
  
  
  CONCLUSIONS
  SOE illumination at lambda 634 nm during moderate cold ischemia (+4 degrees C) can improve the survival of concordant hamster xeno-heart transplants. The exact mechanism(s) are currently unknown, but the effect might in part be exerted by a combination of reduced production of ROS and increased oxidative phosphorylation.
authors.affiliation: Department of Surgery and Transplantation, Wallenberg Laboratory for Cardiovascular Research, Göteborg, Sweden.
authors.forename: D J
authors.initials: DJ
authors.lastname: Lukes
authors.forename: U
authors.initials: U
authors.lastname: Skogsberg
authors.forename: A
authors.initials: A
authors.lastname: Nilsson
authors.forename: A
authors.initials: A
authors.lastname: Lundgren
authors.forename: M
authors.initials: M
authors.lastname: Olausson
authors.forename: B
authors.initials: B
authors.lastname: Soussi
mesh_terms: D000818:Animals; D006224:Cricetinae; D006085:Graft Survival / Q000276:immunology*; D016027:Heart Transplantation / Q000276:immunology*; D007511:Ischemia; D008297:Male; D017202:Myocardial Ischemia; D051381:Rats; D011917:Rats, Inbred Lew; D017382:Reactive Oxygen Species / Q000378:metabolism; D026082:Singlet Oxygen / Q000378:metabolism*; D014183:Transplantation, Heterologous / Q000276:immunology*
chemical_list: D017382:Reactive Oxygen Species; D026082:Singlet Oxygen