title: Evaluation of the oxidative effect of long-term repetitive hyperbaric oxygen exposures on different brain regions of rats.
abstract: Hyperbaric oxygen (HBO(2)) exposure affects both oxidative and antioxidant systems. This effect is positively correlated with the exposure time and duration of the treatment. The present study aims enlightening the relation of HBO(2) with oxidative/antioxidant systems when administered in a prolonged and repetitive manner in brain tissues of rats. Sixty rats were divided into 6 study (n = 8 for each) and 1 control (n = 12) group. Rats in the study groups were daily exposed 90-min HBO(2) sessions at 2.8 ATA for 5, 10, 15, 20, 30 and 40 days. One day after the last session, animals were sacrificed; their whole brain tissue was harvested and dissected into three different regions as the outer grey matter (cortex), the inner white matter and cerebellum. Levels of lipid peroxidation and protein oxidation and activities of superoxide dismutase and glutathione peroxidase were measured in these tissues. Malondialdehyde, carbonylated protein and glutathione peroxidase levels were found to be insignificantly increased at different time-points in the cerebral cortex, inner white matter and cerebellum, respectively. These comparable results provide evidence for the safety of HBO treatments and/or successful adaptive mechanisms at least in the brain tissue of rats, even when administered for longer periods.
authors.affiliation: Department of Undersea and Hyperbaric Medicine, Gulhane Military Medical Academy, 06010 Etlik, Ankara, Turkey. drkemsim@gmail.com
authors.forename: Kemal
authors.initials: K
authors.lastname: Simsek
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ozler
authors.forename: Ali Osman
authors.initials: AO
authors.lastname: Yildirim
authors.forename: Serdar
authors.initials: S
authors.lastname: Sadir
authors.forename: Seref
authors.initials: S
authors.lastname: Demirbas
authors.forename: Muzaffer
authors.initials: M
authors.lastname: Oztosun
authors.forename: Ahmet
authors.initials: A
authors.lastname: Korkmaz
authors.forename: Hakan
authors.initials: H
authors.lastname: Ay
authors.forename: Sukru
authors.initials: S
authors.lastname: Oter
authors.forename: Senol
authors.initials: S
authors.lastname: Yildiz
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism; D006931:Hyperbaric Oxygenation; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D008315:Malondialdehyde; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase