Down regulation of COX-2 is involved in hyperbaric oxygen treatment in a rat transient focal cerebral ischemia model.
The effect of hyperbaric oxygen (HBO) on cyclooxygenase-2 (COX-2) expression after transient focal ischemia was evaluated. A rat middle cerebral artery occlusion/reperfusion (MCAO) model was produced using the intraluminal filament method. After 2 h of occlusion, 24 h of reperfusion, brains were removed. Three atmospheres absolute HBO for 1 h was administered at 6 h after reperfusion. The infarct volume was evaluated by 2,3,7-triphenyltetrazolium chloride staining. COX-2 mRNA expression was measured by reverse transcription polymerase chain reaction, and COX-2 protein expression was analyzed by Western blot. The results showed that HBO applied at 6 h after reperfusion significantly reduces infarct area as compared with no-treatment group. HBO decreased COX-2 mRNA and protein levels, which were upregulated after ischemia/reperfusion. HBO had no direct effect on COX-2 protein expression in matched normal rats. We conclude that (1) early intervention with HBO within 6 h reduces infarction. (2) The neuroprotective effect of HBO might lead to an inhibition of COX-2 over-expression in cerebral cortex.
Yin
Wei
W
Department of Neurosurgery, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216-4505, USA.
Badr
Ahmed E
AE
Mychaskiw
George
G
Zhang
John H
JH
D000818:Animals; D001921:Brain / Q000201:enzymology; D051546:Cyclooxygenase 2; D004195:Disease Models, Animal; D015971:Gene Expression Regulation, Enzymologic; D006931:Hyperbaric Oxygenation; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism / Q000628:therapy; D002546:Ischemic Attack, Transient / Q000378:metabolism* / Q000628:therapy*; D007527:Isoenzymes / Q000235:genetics*; D008297:Male; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley
D007527:Isoenzymes; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases