title: Effects of ozone oxidative preconditioning on liver regeneration after partial hepatectomy in rats.
abstract: OBJECTIVE
  Similar protective effect of ischemic and ozone oxidative preconditioning (OzoneOP) in hepatic ischemia-reperfusion (I/R) injury was demonstrated, providing evidences that both preconditioning settings shared similar biochemical mechanisms of protection. We investigated the effects of OzoneOP on liver regeneration after 70% partial hepatectomy (PHx) in rats.
  
  
  METHODS
  Rats were divided into three groups: PHx, I/R + PHx, and OzoneOP + I/R + PHx groups. Ozone (intraperitoneal, 1.2 mg/kg) was given to rats subjected to I/R and 70% hepatectomy daily five times before operation. At 24 hr and 48 hr after resection, samples were collected for the measurement of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6). Moreover, liver regeneration rate, proliferating cell nuclear antigen (PCNA) labeling index, mitotic index, and histopathological examination were evaluated.
  
  
  RESULTS
  OzoneOP reduced liver injury determined by liver histology and serum transaminases. There was a rise in serum TNF-α and IL-6 levels in the I/R + PHx group whereas OzoneOP significantly decreased the rise in the level of TNF-α but not IL-6 on the 24 hr and 48 hr of reperfusion. Moreover, liver regeneration in OzoneOP + PHx group, as assessed by the regenerated liver weight, mitotic, and PCNA-labeling index, was significantly improved when compared to I/R + PHx group.
  
  
  CONCLUSIONS
  These results suggest that OzoneOP ameliorates the hepatic injury associated with I/R and has a stimulatory effect on liver cell regeneration that may make it valuable as a hepatoprotective modality.
authors.affiliation: Department of General Surgery, School of Medicine, Bulent Ecevit University , Kozlu, Zonguldak , Turkey.
authors.forename: Fatma Ayca
authors.initials: FA
authors.lastname: Gultekin
authors.forename: Guldeniz Karadeniz
authors.initials: GK
authors.lastname: Cakmak
authors.forename: Ummuhani Ozel
authors.initials: UO
authors.lastname: Turkcu
authors.forename: Gamze
authors.initials: G
authors.lastname: Yurdakan
authors.forename: F Ebru Ofluoglu
authors.initials: FE
authors.lastname: Demir
authors.forename: Mustafa
authors.initials: M
authors.lastname: Comert
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D005260:Female; D006498:Hepatectomy; D015850:Interleukin-6 / Q000097:blood; D019194:Ischemic Preconditioning / Q000379:methods*; D008099:Liver / Q000473:pathology; D008115:Liver Regeneration / Q000187:drug effects*; D010126:Ozone / Q000494:pharmacology*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000473:pathology / Q000517:prevention & control*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015850:Interleukin-6; D018809:Proliferating Cell Nuclear Antigen; D014409:Tumor Necrosis Factor-alpha; D010126:Ozone; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase