Abstract |
Matrix metalloproteinase-9 (MMP-9) plays a deleterious role in cell death after global cerebral ischemia. Preconditioning with hyperbaric oxygen (HBO-PC) reduces neuronal damage in the post-ischemic brain; however, its effect on ischemia-induced increase in MMP-9 activity and expression remains unexplored.We investigated effects of HBO-PC on alterations in MMP-9 activity/tissue expression accompanying neuronal death after transient global cerebral ischemia.Male SD rats (300-350 g), were allocated either to non-ischemic (naive control or sham-operated) or ischemic (four-vessel occlusion, 4VO; 10 min) groups that were HBO-preconditioned (2.5 ATA, 1 h daily for 5 days; the last session 24 h before ischemia) or not. Neurobehavioral deficits were assessed prior to collection of brain tissue for gel zymography (MMP-9) and histology ( MMP-9 immunofluorescence, TUNEL) at 0 (without ischemia), 6, 24, 72 h and 7 days after 4VO.Both, MMP-9 levels and cell death increased in the hippocampus at 72 h after 4VO. HBO-PC suppressed postischemic MMP-9 activity and CA1 cell damage, and improved functional performance. The increase in MMP-9 immunoreactivity in the brain was also detected after HBO-PC alone. HBO-PC suppresses MMP-9 activity and expression in the postischemic hippocampus. The mechanism of HBO preconditioning may depend on the induction of MMP-9 in the preischemic phase and may be in part mediated by exhaustion of MMP-9 stores in cerebral tissues.
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Authors | Robert P Ostrowski, Vikram Jadhav, Wanqiu Chen, John H Zhang |
Journal | Acta neurochirurgica. Supplement
(Acta Neurochir Suppl)
Vol. 106
Pg. 47-9
( 2010)
ISSN: 0065-1419 [Print] Austria |
PMID | 19812919
(Publication Type: Journal Article)
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Chemical References |
- Matrix Metalloproteinase 9
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Topics |
- Animals
- Brain
(blood supply, enzymology, pathology)
- Brain Ischemia
(pathology, physiopathology)
- Cell Death
(physiology)
- Disease Models, Animal
- Down-Regulation
(physiology)
- Hyperbaric Oxygenation
(methods)
- In Situ Nick-End Labeling
(methods)
- Ischemic Preconditioning
(methods)
- Male
- Matrix Metalloproteinase 9
(metabolism)
- Rats
- Rats, Sprague-Dawley
- Time Factors
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