title: Hyperbaric oxygenation alters temporal expression pattern of superoxide dismutase 2 after cortical stab injury in rats.
abstract: OBJECTIVE
  To evaluate the effect of hyperbaric oxygen therapy (HBOT) on superoxide dismutase 2 (SOD2) expression pattern after the cortical stab injury (CSI).
  
  
  METHODS
  CSI was performed on 88 male Wistar rats, divided into control, sham, lesioned, and HBO groups. HBOT protocol was the following: pressure applied was 2.5 absolute atmospheres, for 60 minutes, once a day for consecutive 3 or 10 days. The pattern of SOD2 expression and cellular localization was analyzed using real-time polymerase chain reaction, Western blot, and double-label fluorescence immunohistochemistry. Neurons undergoing degeneration were visualized with Fluoro-Jade®B.
  
  
  RESULTS
  CSI induced significant transient increase in SOD2 protein levels at day 3 post injury, which was followed by a reduction toward control levels at post-injury day 10. At the same time points, mRNA levels for SOD2 in the injured cortex were down-regulated. Exposure to HBO for 3 days considerably down-regulated SOD2 protein levels in the injured cortex, while after 10 days of HBOT an up-regulation of SOD2 was observed. HBOT significantly increased mRNA levels for SOD2 at both time points compared to the corresponding L group, but they were still lower than in controls. Double immunofluorescence staining revealed that 3 days after CSI, up-regulation of SOD2 was mostly due to an increased expression in reactive astrocytes surrounding the lesion site. HBOT attenuated SOD2 expression both in neuronal and astroglial cells. Fluoro-Jade®B labeling showed that HBOT significantly decreased the number of degenerating neurons in the injured cortex.
  
  
  CONCLUSIONS
  HBOT alters SOD2 protein and mRNA levels after brain injury in a time-dependent manner.
authors.affiliation: Department of Neurobiology, Institute for Biological Research Sinisa Stankovic, University of Belgrade, Blvd Despota Stefana 142, 11060 Belgrade, Serbia. parabucki@ibiss.bg.ac.rs
authors.forename: Ana B
authors.initials: AB
authors.lastname: Parabucki
authors.forename: Iva D
authors.initials: ID
authors.lastname: Bozić
authors.forename: Ivana M
authors.initials: IM
authors.lastname: Bjelobaba
authors.forename: Irena C
authors.initials: IC
authors.lastname: Lavrnja
authors.forename: Predrag D
authors.initials: PD
authors.lastname: Brkić
authors.forename: Tomislav S
authors.initials: TS
authors.lastname: Jovanović
authors.forename: Danijela Z
authors.initials: DZ
authors.lastname: Savić
authors.forename: Mirjana B
authors.initials: MB
authors.lastname: Stojiljković
authors.forename: Sanja M
authors.initials: SM
authors.lastname: Peković
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001930:Brain Injuries / Q000201:enzymology* / Q000628:therapy; D015536:Down-Regulation; D019084:Fluorescent Antibody Technique, Indirect; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D006931:Hyperbaric Oxygenation; D007150:Immunohistochemistry; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics* / Q000378:metabolism*; D013997:Time Factors; D000099156:Superoxide Dismutase 2
chemical_list: D012333:RNA, Messenger; D013482:Superoxide Dismutase; D000099156:Superoxide Dismutase 2