title: Inhibition of Rho-kinase protects cerebral barrier from ischaemia-evoked injury through modulations of endothelial cell oxidative stress and tight junctions.
abstract: Ischaemic strokes evoke blood-brain barrier (BBB) disruption and oedema formation through a series of mechanisms involving Rho-kinase activation. Using an animal model of human focal cerebral ischaemia, this study assessed and confirmed the therapeutic potential of Rho-kinase inhibition during the acute phase of stroke by displaying significantly improved functional outcome and reduced cerebral lesion and oedema volumes in fasudil- versus vehicle-treated animals. Analyses of ipsilateral and contralateral brain samples obtained from mice treated with vehicle or fasudil at the onset of reperfusion plus 4 h post-ischaemia or 4 h post-ischaemia alone revealed these benefits to be independent of changes in the activity and expressions of oxidative stress- and tight junction-related parameters. However, closer scrutiny of the same parameters in brain microvascular endothelial cells subjected to oxygen-glucose deprivation ± reperfusion revealed marked increases in prooxidant NADPH oxidase enzyme activity, superoxide anion release and in expressions of antioxidant enzyme catalase and tight junction protein claudin-5. Cotreatment of cells with Y-27632 prevented all of these changes and protected in vitro barrier integrity and function. These findings suggest that inhibition of Rho-kinase after acute ischaemic attacks improves cerebral integrity and function through regulation of endothelial cell oxidative stress and reorganization of intercellular junctions. Inhibition of Rho-kinase (ROCK) activity in a mouse model of human ischaemic stroke significantly improved functional outcome while reducing cerebral lesion and oedema volumes compared to vehicle-treated counterparts. Studies conducted with brain microvascular endothelial cells exposed to OGD ± R in the presence of Y-27632 revealed restoration of intercellular junctions and suppression of prooxidant NADPH oxidase activity as important factors in ROCK inhibition-mediated BBB protection.
authors: School of Psychology, University of Leicester, Leicester, UK.
authors: Claire L
authors: CL
authors: Gibson
authors: Kirtiman
authors: K
authors: Srivastava
authors: Nikola
authors: N
authors: Sprigg
authors: Philip M W
authors: PM
authors: Bath
authors: Ulvi
authors: U
authors: Bayraktutan
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000577:Amides / Q000494:pharmacology; D000818:Animals; D001253:Astrocytes / Q000187:drug effects; D001812:Blood-Brain Barrier / Q000187:drug effects*; D015153:Blotting, Western; D001923:Brain Chemistry / Q000187:drug effects; D002545:Brain Ischemia / Q000473:pathology* / Q000517:prevention & control*; D002478:Cells, Cultured; D002544:Cerebral Infarction / Q000473:pathology; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D007839:Functional Laterality / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019255:NADPH Oxidases / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000096:biosynthesis; D018384:Oxidative Stress / Q000187:drug effects*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D011725:Pyridines / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D019108:Tight Junctions / Q000187:drug effects / Q000473:pathology*; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors*
chemical_list: D000577:Amides; D009419:Nerve Tissue Proteins; D047428:Protein Kinase Inhibitors; D011725:Pyridines; D017382:Reactive Oxygen Species; C108830:Y 27632; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D019255:NADPH Oxidases; D054460:rho-Associated Kinases; C049347:fasudil
keywords: Rho-kinase inhibitor; blood-brain barrier; brain microvascular endothelial cells; brain oedema; ischaemic stroke; oxidative stress