title: Preconditioning with hyperbaric oxygen induces tolerance against renal ischemia-reperfusion injury via increased expression of heme oxygenase-1.
abstract: OBJECTIVE
  Renal ischemia/reperfusion (I/R) injury occurs in both native and transplanted kidneys. Hyperbaric oxygen (HBO) has been shown to prevent I/R injury in different tissues. The aim of this study was to evaluate the effect of HBO on renal I/R injury in rats.
  
  
  METHODS
  Male Sprague-Dawley rats were randomly assigned to three groups. The sham group (n = 8) received right nephrectomy. The I/R (n = 8) and HBO + I/R groups (n = 8) received 45 min left renal ischemia followed by 24 h of reperfusion after right nephrectomy. The HBO + I/R group (n = 8) received 100% oxygen at 2.5 atmosphere absolute (ATA), for 1 h at every 12 h interval for 2 d. Reperfusion was performed 24 h later after the last HBO exposure.
  
  
  RESULTS
  In HBO + I/R group, blood urea nitrogen (BUN) and creatinine levels decreased significantly compared with the sham and I/R groups (P < 0.01). Activities of superoxide dismutase (SOD) were increased in renal tissue in the HBO + I/R groups. The content of malondialdehyde (MDA) were decreased in the HBO + I/R groups. Kidney samples from HBO + I/R group rats revealed markedly reduced histological damage under histopathological examination. The animals treated with HBO showed significantly elevated heme oxygenase-1 (HO-1) protein and mRNA levels expression compared with I/R group (P < 0.05).
  
  
  CONCLUSIONS
  Hyperbaric oxygen preconditioning (HBO-PC) can protect renal I/R injury against oxidative stress, and the up-regulation of HO-1 expression plays an essential role in HBO induced preconditioning effect.
authors.affiliation: Department of Urology, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu Province, China. fnmong@hotmail.com
authors.forename: Xiaozhou
authors.initials: X
authors.lastname: He
authors.forename: Xianlin
authors.initials: X
authors.lastname: Xu
authors.forename: Min
authors.initials: M
authors.lastname: Fan
authors.forename: Xiao
authors.initials: X
authors.lastname: Chen
authors.forename: Xuejun
authors.initials: X
authors.lastname: Sun
authors.forename: Guanghua
authors.initials: G
authors.lastname: Luo
authors.forename: Lujun
authors.initials: L
authors.lastname: Chen
authors.forename: Qinfeng
authors.initials: Q
authors.lastname: Mu
authors.forename: Yuehua
authors.initials: Y
authors.lastname: Feng
authors.forename: Qingyan
authors.initials: Q
authors.lastname: Mao
authors.forename: Zhifu
authors.initials: Z
authors.lastname: Chao
mesh_terms: D000818:Animals; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism*; D006931:Hyperbaric Oxygenation / Q000379:methods*; D019194:Ischemic Preconditioning / Q000379:methods*; D007674:Kidney Diseases / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D007677:Kidney Function Tests; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D013482:Superoxide Dismutase / Q000378:metabolism; D015854:Up-Regulation / Q000502:physiology
chemical_list: D008315:Malondialdehyde; D006419:Heme Oxygenase (Decyclizing); C491523:Hmox1 protein, rat; D013482:Superoxide Dismutase