Background and Purpose-FTY720 is a known sphingosine 1-phosphate receptor agonist. In the present study, we investigated the neuroprotective effect of postischemic administration of FTY720 in rats with 2 hours transient middle cerebral artery occlusion (MCAO). Methods-One hundred eleven male rats were randomly assigned to sham-operated and MCAO treated with vehicle, 0.25 mg/kg and 1 mg/kg of FTY720, another selective sphingosine 1-phosphate receptor-1 agonist SEW2871 (5 mg/kg), or 0.25 mg/kg of FTY720 plus a sphingosine 1-phosphate antagonist, VPC23019 (0.5 mg/kg). Drugs were injected intraperitoneally immediately after reperfusion. Neurological score and infarct volume were assessed at 24 and 72 hours after MCAO. Western blotting, immunohistochemistry, and terminal deoxynucleotidyl transferase-mediated uridine 5Ј-triphosphate-biotin nick end-labeling were conducted at 24 hours after MCAO. Results-FTY720 significantly reduced infarct volume and improved neurological score at 24 and 72 hours after MCAO compared with the vehicle group. SEW2871 showed similar neuroprotective effects to FTY720, whereas VPC 20319 abolished the neuroprotective effects of FTY720. FTY720 significantly retained Akt and extracellular signal-regulated kinase phosphorylation and Bcl-2 expression and decreased cleaved caspase-3 expression and terminal deoxynucleotidyl transferase-mediated uridine 5Ј-triphosphate-biotin nick end-labeling-positive neurons at 24 hours after MCAO. VPC23019 blocked the antiapoptotic effects of FTY720. Conclusions-These data suggest that activation of sphingosine 1-phosphate-1 by FTY720 reduces neuronal death after transient MCAO. (Stroke. 2010;41:368-374.)

Background and Purpose-The role of interleukin (IL)-1␤ remains unknown in early brain injury (EBI) after subarachnoid hemorrhage (SAH), although IL-1␤ has been repeatedly reported to increase in the brain and cerebrospinal fluid. The aim of this study is to examine the effects of IL-1␤ inactivation on EBI after SAH in mice. Methods-The endovascular perforation model of SAH was produced and 112 mice were assigned to sham, SAHϩ vehicle, and SAHϩ N-Ac-Tyr-Val-Ala-Asp-chloromethyl ketone (Ac-YVAD-CMK, 6 and 10 mg/kg) groups. Ac-YVAD-CMK, a selective inhibitor of IL-1␤ converting enzyme, or vehicle was administered intraperitoneally 1 hour post-SAH. EBI was assessed in terms of mortality within 24 hours, neurological scores, brain water content at 24 and 72 hours, Evans blue dye extravasation and Western blot for IL-1␤, c-Jun N-Terminal kinase (JNK), matrix metalloproteinase (MMP)-9, and zonula occludens (ZO)-1 at 24 hours after SAH. Results-High-dose (10 mg/kg) but not low-dose (6 mg/kg) treatment group significantly improved neurological scores, mortality, brain water content, and Evans blue dye extravasation compared with the vehicle group. Although both dosages of Ac-YVAD-CMK attenuated the mature IL-1␤ induction, only high-dose treatment group significantly inhibited the phosphorylation of JNK, MMP-9 induction, and ZO-1 degradation. Conclusion-IL-1␤

Objective-Accumulated evidence suggests that the primary cause of poor outcome after subarachnoid hemorrhage (SAH) is not only cerebral arterial narrowing, but also early brain injury (EBI). Our objective was to determine the effect of recombinant osteopontin (r-OPN), a pleiotropic extracellular matrix glycoprotein, on post-SAH EBI in rats. Design-Controlled in vivo laboratory study. Setting-Animal research laboratory.Subjects-One hundred seventy-seven male adult Sprague-Dawley rats, 300-370g.Interventions-The endovascular perforation model of SAH was produced. SAH or shamoperated rats were treated with an equal volume (1μL) of pre-SAH intracerebroventricular administration of two dosages (0.02 and 0.1μg) of r-OPN, albumin or vehicle. Body weight, neurological scores, brain edema and blood-brain barrier (BBB) disruption were evaluated, and Western blot analyses were performed to determine the effect of r-OPN on matrix metalloproteinase (MMP)-9, substrates of MMP-9 (zona occludens [ZO]-1, laminin), tissue inhibitor of MMP (TIMP)-1, inflammation (interleukin-1β), and nuclear factor (NF)-κ B signaling pathways. Measurements and MainResults-Treatment with r-OPN prevented a significant loss in body weight, neurological impairment, brain edema, and BBB disruption after SAH. These effects were associated with the deactivation of NF-κB activity, inhibition of MMP-9 induction, the maintenance of TIMP-1, and the consequent preservation of the cerebral microvessel basal lamina protein laminin, and the tight junction protein ZO-1.Conclusions-These results demonstrate that r-OPN treatment is effective for post-SAH EBI. Aneurysmal subarachnoid hemorrhage (SAH) is a common and devastating neurological disorder (1). Cerebral vasospasm has been believed to be a leading cause of mortality and morbidity (2). Recent randomized clinical trials, however, showed that clazosentan significantly reduced angiographic vasospasm but failed to improve long-term neurological outcome (3,4). This means that the treatment efforts targeting only angiographic vasospasm might not be enough to achieve a better outcome. Thus, new research efforts have focused on clarifying the pathophysiology of early brain injury (EBI) following SAH, and on developing protective strategies against it (5).Osteopontin (OPN) is a secreted extracellular matrix (ECM) glycoprotein that is involved in both physiological and pathological processes in a wide range of tissue (6). The biological functions of OPN are highly variable, and often seemingly contradictory depending on the biological scenario surrounding its induction (7). However, there is compelling evidence that OPN can, in a variety of situations, help cells survive an otherwise lethal insult (8). For example, endogenous OPN induction has consistently been found to have protective effects on ischemic injuries involving the brain and other organs (9,10). Moreover, the administration of recombinant OPN (r-OPN) markedly reduced the infarct size via anti-apoptotic actions in a transient focal cerebral ischemi...

The study of apoptosis in EBI after experimental SAH may give us new therapies for SAH.

Among many proinflammatory cytokines, interleukin-1β (IL-1β) is considered a key mediator of neuronal injury. However, in order to become activated, it must be processed and cleaved by a caspase-1 enzyme. In this study, we tested the neuroprotective effect of Ac-YVAD-CMK, a known selective caspase-1 inhibitor, in a mouse model of intracerebral hemorrhage (ICH). Sixty-six adult male CD-1 mice were subjected to collagenase-induced ICH. Ac-YVAD-CMK or vehicle was administered into the left lateral ventricle 20 min before ICH modeling. Brain edema and neurological functions were assessed at 24 and 72 h after the surgery. Expression of IL-1β, phosphorylated JNK, tight junction protein zona occludens 1 (ZO-1), and matrix metalloproteinase-9 (MMP-9) were measured by Western blot along with MMP-9 activity measured by zymography at 24 h after ICH. At 24 h after ICH, Ac-YVAD-CMK treatment significantly reduced brain edema and improved © Springer Science+Business Media, LLC 2009Correspondence to: Jiping Tang, jtang@llu.edu. NIH Public Access Author ManuscriptTransl Stroke Res. Author manuscript; available in PMC 2011 March 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript neurological functions. The neuroprotection was associated with downregulation of IL-1β, JNK, MMP-9, and an inhibition of ZO-1 degradation in brain. We conclude that Ac-YVAD-CMK protects the brain against ICH-induced injury, and the neuroprotective effect may result from antiinflammation-induced blood-brain barrier protection.

Background and Purpose-We examined the effects of a caspase-1 inhibitor, N-Ac-Tyr-Val-Ala-Asp-chloromethyl ketone (Ac-YVAD-CMK), on neurogenic pulmonary edema in the endovascular perforation model of subarachnoid hemorrhage (SAH) in mice. Methods-Ninety-seven mice were assigned to sham, SAHϩvehicle, SAHϩAc-YVAD-CMK (6 or 10 mg/kg), and SAHϩZ-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK, 6 mg/kg) groups. Drugs were intraperitoneally injected 1 hour post-SAH. Pulmonary edema measurements, Western blot for interleukin-1␤, interleukin-18, myeloperoxidase, matrix metalloproteinase (MMP)-2, MMP-9, cleaved caspase-3 and zona occludens-1, MMP zymography, terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining, and immunostaining were performed on the lung at 24 hours post-SAH. Results-Ten-but not 6-mg/kg of Ac-YVAD-CMK significantly inhibited a post-SAH increase in the activation of interleukin-1␤ and caspase-3 and the number of terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling-positive pulmonary endothelial cells, preventing neurogenic pulmonary edema. Another antiapoptotic drug, Z-VAD-FMK, also reduced neurogenic pulmonary edema. SAH did not change interleukin-18, myeloperoxidase, MMP-2, MMP-9, zona occludens-1 levels, or MMP activity. Conclusions-We report for the first time that Ac-YVAD-CMK prevents lung cell apoptosis and neurogenic pulmonary edema after SAH in mice.

It has been reported that gap junction contributes to ischemic brain injury and gap junction inhibitors improve neurological outcome in ischemic brain injury models. In the present study, we investigated the effects of gap junction inhibitor, carbenoxolone, on mortality, neurological deficits and brain edema in mice with intracerebral hemorrhage. A total of 80 male CD-1 mice were divided into two parts with two end-points for this study. In part one, animals were divided into four groups: sham, vehicle treatment following intracerebral hemorrhage induction, low-dose carbenoxolone (33 mg/kg) treatment 1 hour after intracerebral hemorrhage induction and high-dose carbenoxolone (100 mg/kg) treatment 1 hour after intracerebral hemorrhage induction groups. Animals were euthanized after 24 hours. In part two, animals were divided into four groups: sham, vehicle treatment 1 hour after intracerebral hemorrhage induction, single high-dose of carbenoxolone treatment at 1 hour after intracerebral hemorrhage induction and three high-doses of carbenoxolone treatment 1, 24 and 48 hours respectively after intracerebral hemorrhage induction. Animals were euthanized after 72 hours. Intracerebral hemorrhage was induced by collagenase injection. Neurological deficits were evaluated using modified Garcia's neurological test, wire hanging and beam balance tests. Brain edema was measured by brain water content. Our results showed that intracerebral hemorrhage produced brain edema and neurological deficits in mice. Carbenoxolone treatment failed to reduce brain edema and neurological deficits. In fact, the high dose of carbenoxolone aggravated neurological deficits and increased mortality 72 hours after the treatment. In conclusion, inhibition of gap junction has no short-term neuroprotective effect on intracerebral hemorrhage-induced brain injury. Further studies are required to assess the long-term effects of gap junction inhibitors in intracerebral hemorrhage models.

The continuation of a review of delayed vasospasm after aneurysmal subarachnoid haemorrhage, originally published in 1994 and partially updated at the ninth vasospasm conference in Turkey, is presented. Further online and physical searches have been made of the relevant literature. The incidence of delayed ischaemic deficit (DID) or symptomatic vasospasm reported in 1994 was 32.5% in over 30,000 reported cases. In recent years, 1994-2009, it was 6,775/23,806, or 28.5%. Many of the recent reports did not specify whether a calcium antagonist was used routinely, and when this was stated (usually nimodipine or nicardipine), DID was noted in 22.0% of 10,739 reported patients. The outcome of delayed ischaemia in the earlier survey was a death rate of 31.6%, with favourable outcomes in 36.2%. In recent reports, though with fewer than 1,000 patients, the outcome is possibly better, with death in 25.6% and good outcome in 54.1%. It thus appears likely that delayed vasospasm is still common but less so, and that the overall outcome has improved. This may be due to the more widespread use of calcium antagonists and more effective fluid management. A number of other mechanical and drug treatments are also mentioned.