Hyperbaric oxygen preconditioning reduces ischemia-reperfusion injury by inhibition of apoptosis via mitochondrial pathway in rat brain.
This study examined the hypothesis that apoptotic inhibition via mitochondrial pathway was involved in hyperbaric oxygen preconditioning (HBO-PC)-induced neuroprotection on ischemia-reperfusion injury in rat brain. Male Sprague-Dawley rats (250 approximately 280 g, n=144) were divided into control, middle cerebral artery occlusion (MCAO) for 90 min, and HBO-PC plus MCAO groups. HBO-PC was conducted four times by giving 100% oxygen at 2.5 atm absolute (ATA), for 1 h at 12 h intervals for 2 days. At 24 h after the last HBO-PC, MCAO was performed and at 24 h after MCAO, neurological function, brain water content, infarct volume, and cell death were evaluated. Enzymatic activity of capase-3 and -9, and expression of cytochrome c, Bcl-2 and Bax proteins were performed in the samples from hippocampus, ischemic penumbra and core of the brain cortex, respectively. HBO-PC reduced brain edema, decreased infarction volume, and improved neurological recovery. HBO-PC reduced cytoplasm cytochrome c levels, decreased caspase enzyme activity, upregulated the ratio of Bcl-2 and Bax expression, and abated the apoptosis of ischemic tissue. HBO-PC protects brain tissues from ischemia-reperfusion injury by suppressing mitochondrial apoptotic pathways.
Li
J-S
JS
Department of Neurology, Changhai Hospital, 168 Changhai Road, Shanghai, PR China.
Zhang
W
W
Kang
Z-M
ZM
Ding
S-J
SJ
Liu
W-W
WW
Zhang
J H
JH
Guan
Y-T
YT
Sun
X-J
XJ
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology; D045304:Cytochromes c / Q000378:metabolism; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology; D006931:Hyperbaric Oxygenation; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008928:Mitochondria / Q000502:physiology*; D009043:Motor Activity / Q000502:physiology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000473:pathology / Q000517:prevention & control / Q000628:therapy*; D014867:Water / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
C494828:Bax protein, rat; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D014867:Water; D045304:Cytochromes c; C505410:Casp3 protein, rat; C506435:Casp9 protein, rat; D053148:Caspase 3; D053453:Caspase 9