Abstract 154: Protection from Transient Focal Cerebral Ischemia by Transfusion of Polynitroxylated Pegylated Hemoglobin

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Jian Zhang ◽  
Suyi Cao ◽  
Li Ma ◽  
Carleton J Hsia ◽  
Raymond C Koehler

Polynitroxylation of hemoglobin (Hb) confers superoxide dismutase and catalase mimetic activity and can protect neurons from native Hb and glutamate. Here, we determined if transfusion of polynitroxylated pegylated Hb (PNPH) is protective in the rat filament model of 2 h of middle cerebral artery occlusion (MCAO). Transfusion of 10 ml/kg of PNPH at 20 min of MCAO reduced the median infarct volume in cerebral cortex from 40% (37-47% interquartile range; n=10) in controls to 3% (0-7%; n=10; P<0.001) with PNPH and in striatum from 78% (66-88%) to 34% (0-37%; P<0.001). The therapeutic window was evaluated in a second experiment. Compared to the control median hemispheric infarct volume of 22% (13-34%; n=15), infarct volume was reduced to 7% (3-13%; n=14; P<0.05) when PNPH was transfused at 4 h after MCAO (2 h of reperfusion) but not significantly when transfused at 6 h (8%; 3-35%; n=14) or at 8 h (12%; 10-25%; n=14) after MCAO. To determine whether PNPH might act by promoting vasodilation, pial arteriolar diameter in the distal MCA border region was measured in closed cranial windows during MCAO. With no transfusion, MCAO induced an initial dilation (36±5%; ±SD; n=8) that subsided by 2 h (5±11%). With PNPH transfusion at 20 min of MCAO, the initial dilation (31±8%; n=7) was better maintained at 2 h (21±11%; P<0.02). To determine whether delaying PNPH transfusion until 90 min of MCAO would improve penumbral perfusion, laser-Doppler flow (LDF) was measured in the ischemic border region where the reduction in LDF was less severe than in the core. LDF significantly increased from 48±18% of the pre-ischemic baseline to 67±21% (P<0.005). Thus, PNPH transfusion has a significant therapeutic window for protection from transient MCAO and may act, in part, by stabilizing vascular function and improving collateral blood flow.

1999 ◽  
Vol 19 (7) ◽  
pp. 778-787 ◽  
Author(s):  
Satoshi Kuroda ◽  
Ryoichi Tsuchidate ◽  
Maj-Lis Smith ◽  
Kirk R. Maples ◽  
Bo K. Siesjö

Recent results have demonstrated that the spin trapping agent α-phenyl- N- tert-butyl nitrone (PBN) reduces infarct volume in rats subjected to 2 hours of middle cerebral artery occlusion, even when given 1 to 3 hours after the start of recirculation. In the current study, the authors assessed the effect of NXY-059, a novel nitrone that is more soluble than PBN. Loading doses were given of 0.30, 3.0, or 30 mg · kg−1 followed by 0.30, 3.0, or 30 mg · kg−1 · h−1 for 24 or 48 hours. Dose–response studies showed that when treatment was begun 1 hour after recirculation, 0.30 mg · kg−1 had a small and 30 mg · kg-i a marked effect on infarct volume. At equimolar doses (3.0 mg · kg−1 for NXY-059 and 1.4 mg · kg−1 for PBN), NXY-059 was more efficacious than PBN. Similar results were obtained when a recovery period of 7 days was allowed. The window of therapeutic opportunity for NXY-059 was 3 to 6 hours after the start of recirculation. Studies of the transfer constant of [14C]NXY-059 showed that, in contrast to PBN, this more soluble nitrone penetrates the blood-brain barrier less extensively. This fact, and the pronounced antiischemic effect of NXY-059, suggest that the delayed events leading to infarction may be influenced by reactions occurring at the blood–endothelial interface.


2008 ◽  
Vol 28 (12) ◽  
pp. 1927-1935 ◽  
Author(s):  
Keita Mayanagi ◽  
Prasad V Katakam ◽  
Tamas Gáspár ◽  
Ferenc Domoki ◽  
David W Busija

The purpose of this study was to investigate the short-term effects of rosuvastatin (RSV), a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, on transient, focal cerebral ischemia in C57BL/6J ob/ob mice with insulin resistance (IR). Male ob/ob, lean, or wild-type (WT) mice were treated with RSV (10 mg/kg per day, i.p.) or vehicle for 3 days. Ischemia was induced by 60 mins of middle cerebral artery occlusion (MCAO) and cortical blood flow (CBF) was monitored by laser-Doppler flowmetry. Infarct volumes were measured 24 h after reperfusion. IR mice exhibited a higher infarct volume compared with Lean or WT mice, and RSV reduced infarct volume only in obese mice (40% ± 3% versus 32% ± 3%, P < 0.05). Blood cholesterol and insulin levels were elevated in ob/ob mice but were unaffected by RSV. The CBF reductions during MCAO were similar in all groups and were not affected by RSV. Although RSV did not increase cortical endothelial NO synthase (eNOS) levels in the ob/ob mice, it attenuated the increased cortical expression of intracellular adhesion molecule-1 (ICAM-1) after MCAO from ob/ob mice. Thus, RSV protects against stroke in IR mice by a mechanism independent of effects on the lipid profile, CBF, or eNOS but dependent on suppression of post-MCAO ICAM-1 expression.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Lingguang Liu ◽  
R. T. F. Cheung

Both melatonin and electroacupuncture (EA) have been suggested to be effective treatments against stroke. However, it is unknown whether a combination of these two therapies could be beneficial against transient focal cerebral ischemia. The present study investigated the effects of pretreatment of a combination of melatonin and EA in a rat model of transient middle cerebral artery occlusion (MCAO). After pretreatment of melatonin plus EA (MEA), transient MCAO was induced for 90 minutes in male Sprague-Dawley (SD) rats. The neurological deficit score, brain infarct volume, cerebral edema ratio, neuronal inflammation, and apoptosis were evaluated 24 hours after transient MCAO. The expression of related inflammatory and apoptotic mediators in the brain was also investigated. The results showed that MEA improved neurological outcome, reduced brain infarct volume, and inhibited neuronal inflammation as well as apoptosis 24 hours after transient MCAO. The beneficial effects may derive from downregulation of proinflammatory and proapoptotic mediators and upregulation of antiapoptotic mediators. Thus, these results suggest a preventive effect of pretreatment of MEA on transient focal cerebral ischemia.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Hui Hu ◽  
Xiao ou Sun ◽  
Fang Tian ◽  
Hao Zhang ◽  
Qing Liu ◽  
...  

Previous report has indicated that isosteviol has neuroprotective effects. However, isosteviol was administered preventively before ischemia and the inclusion criteria were limited. In the present study, a more soluble and injectable form of isosteviol sodium (STVNA) was administered intravenously hours after transient or permanent middle cerebral artery occlusion (tMCAO or pMCAO) to investigate its neuroprotective effects in rats. The rats were assessed for neurobehavioral deficits 24 hours after ischemia and sacrificed for infarct volume quantification and histology evaluation. STVNA 10 mg·kg−1can significantly reduce the infarct volumes compared with vehicle in animals subjected to tMCAO and is twice as potent as previously reported. Additionally, the therapeutic window study showed that STVNA could reduce the infarct volume compared with the vehicle group when administered 4 hours after reperfusion. A similar effect was also observed in animals treated 4 hours after pMCAO. Assessment of neurobehavioral deficits after 24 hours showed that STVNA treatment significantly reduced neurobehavioral impairments. The number of restored NeuN-labeled neurons was increased and the number of TUNEL positive cells was reduced in animals that received STVNA treatment compared with vehicle group. All of these findings suggest that STVNA might provide therapeutic benefits against cerebral ischemia-induced injury.


2006 ◽  
Vol 95 (01) ◽  
pp. 166-173 ◽  
Author(s):  
Li Zhang ◽  
Zheng Zhang ◽  
Xianshuang Liu ◽  
Ann Hozeska ◽  
Nancy Stagliano ◽  
...  

SummaryStroke elicits a progressive vascular dysfunction, which contributes to the evolution of brain injury. Thrombolysis with tissue plasminogen activator (tPA) promotes adverse vascular events that limit the therapeutic window of stroke to three hours. Proteasome inhibitors reduce vascular thrombotic and inflammatory events, and consequently protect vascular function. The present study evaluated the neuroprotective effect of bortezomib,a potent and selective inhibitor of the proteasome, alone and in combination with delayed thrombolytic therapy on a rat model of embolic focal cerebral ischemia. Treatment with bortezomib reduces adverse cerebrovascular events including secondary thrombosis,inflammatory responses,and blood brain barrier (BBB) disruption, and hence reduces infarct volume and neurological functional deficit when administrated within 4 h after stroke onset. Combination of bortezomib and tPA extends the thrombolytic window for stroke to6 h, which is associated with the improvement of vascular patency and integrity. Real time RT-PCR of endothelial cells isolated by laser-capture microdissection from brain tissue and Western blot analysis showed that bortezomib upregulates endothelial nitric oxide synthase (eNOS) expression and blocks NF-κB activation. These results demonstrate that bortezomib promotes eNOS dependent vascular protection, and reduces NF-κB dependent vascular disruption, all of which may contribute to neuroprotection after stroke.


2017 ◽  
Vol 12 (6) ◽  
pp. 628-635 ◽  
Author(s):  
Li Zhang ◽  
Michael Chopp ◽  
Mei Lu ◽  
Talan Zhang ◽  
Chao Li ◽  
...  

Background and aims In an effort to characterize the effects of Cerebrolysin for treatment of stroke that are essential for successful clinical translation, we have demonstrated that Cerebrolysin dose dependently enhanced neurological functional recovery in experimental stroke. Here, we conduct a prospective, randomized, placebo-controlled, blinded study to examine the therapeutic window of Cerebrolysin treatment of rats subjected to embolic stroke. Methods Male Wistar rats age 3–4 months (n = 100) were subjected to embolic middle cerebral artery occlusion. Animals were randomized to receive saline or Cerebrolysin daily for 10 consecutive days starting 4, 24, 48, and 72 h after middle cerebral artery occlusion. Neurological outcome was measured weekly with a battery of behavioral tests (adhesive removal test, modified neurological severity score (mNSS), and foot-fault test). Global test was employed to assess Cerebrolysin effect on neurological recovery with estimation of mean difference between Cerebrolysin and control-treated groups and its 95% confidence interval in the intent-to-treat population, where a negative value of the mean difference and 95% confidence interval < 0 indicated a significant treatment effect. All rats were sacrificed 28 days after middle cerebral artery occlusion and infarct volume was measured. Results Cerebrolysin treatment initiated within 48 h after middle cerebral artery occlusion onset significantly improved functional outcome; mean differences and 95% confidence interval were −11.6 (−17.7, −5.4) at 4 h, −7.1 (−13.5, −0.8) at 24 h, −8.4 (−14.2, −8.6) at 48 h, and −4.9 (−11.4, 1.5) at 72 h. There were no differences on infarct volume and mortality rate among groups. Conclusions With a clinically relevant rigorous experimental design, our data demonstrate that Cerebrolysin treatment effectively improves stroke recovery when administered up to 48 h after middle cerebral artery occlusion.


1996 ◽  
Vol 16 (2) ◽  
pp. 221-226 ◽  
Author(s):  
Kazushi Matsushima ◽  
Matthew J. Hogan ◽  
Antoine M. Hakim

The possibility that cortical spreading depression (CSD) may have neuroprotective action during subsequent focal cerebral ischemia was examined in rats. Three days before the imposition of focal cerebral ischemia CSDs were elicited by applying potassium chloride (KCl) for 2 h through a microdialysis probe implanted in the occipital cortex. Control animals were handled identically except that saline was infused instead of KCl. Focal ischemia was produced by the intraluminal suture method and cortical and subcortical infarct volumes were measured 7 days later. Neocortical infarct volume was reduced from 124.8 ± 49.5 mm3 in the controls to 62.9 ± 59.5 mm3 in the animals preconditioned with CSD (p = 0.012). There was no difference between the two groups in the subcortical infarct volume or in CBF, measured by the hydrogen clearance method, during or immediately after the ischemic interval. Our data indicate that preconditioning CSD applied 3 days before middle cerebral artery occlusion may increase the brain's resistance to focal ischemic damage and may be used as a model to explore the neuroprotective molecular responses of neuronal and glial cells.


2016 ◽  
Vol 39 (4) ◽  
pp. 1339-1346 ◽  
Author(s):  
Lichun Pei ◽  
Songyan Meng ◽  
Weigang Yu ◽  
Qiujun Wang ◽  
Fangfang Song ◽  
...  

Background: Peroxisome proliferator-activated receptor gamma (PPARγ) plays a critical role in protecting against distinct brain damages, including ischemia. Our previous data have shown that the protein level of PPARγ is increased in the cortex after middle cerebral artery occlusion (MCAO); PPARγ up-regulation contributes to PPARγ activation and is effective in reducing ischemic damage to brain. However, the regulatory mechanism of PPARγ after focal cerebral ischemia in rats is still unclear. In this study, we evaluated the effect of microRNA on PPARγ in rats subjected to MCAO. Methods: Focal cerebral ischemia was established by surgical middle cerebral artery occlusion; the protein level of PPARγ was detected by Western blotting; the level of microRNA-383 (miR-383) was quantified by real-time PCR; the neurological outcomes were defined by infarct volume and neurological deficits. Luciferase assay was used to identify the luciferase activities of PPARγ and miR-383. Results: We showed here that miR-383 level was down-regulated in the ischemic hemisphere of rats 24h after MCAO. Overexpression of miR-383 by miR-383 agomir increased infarct volume and aggravated neurological damage. Administration of miR-383 antagomir had the opposite effects. Furthermore, we found that PPARγ protein was down-regulated by miR-383 overexpression, and up-regulated by miR-383 inhibition both in rat model of MCAO and in primary culture cells. Finally, we found that miR-383 suppressed the luciferase activity of the vector carrying the 3'UTR of PPARγ, whereas mutation of the binding sites relived the repressive effect of miR-383. Conclusion: Our study demonstrated that miR-383 may play a key role in focal cerebral ischemia by regulating PPARγ expression at the post-transcriptional level, and miR-383 may be a potential therapeutic target for stroke.


1996 ◽  
Vol 16 (1) ◽  
pp. 107-113 ◽  
Author(s):  
I. Margaill ◽  
S. Parmentier ◽  
J. Callebert ◽  
M. Allix ◽  
R. G. Boulu ◽  
...  

The present study investigates the role of N-methyl-D-aspartate (NMDA) receptors in a model of transient focal cerebral ischemia in normotensive rats. The left middle cerebral artery and both common carotid arteries were occluded for 60 min. Preliminary studies indicated that this gave reproducible infarctions of the cortex and striatum. These infarctions were the result of severe ischemia followed by complete reperfusion after clamp removal, as showed by striatal tissue Po2 monitoring. Microdialysis indicated that glutamate concentration increased immediately after occlusion and returned to the baseline value 40 min after clamp removal. MK-801 (1 mg kg−1 i.v.), an antagonist of the NMDA glutamatergic receptor, reduced the cortical infarct volume by 29% (p < 0.001) and the striatal infarct volume by 14% (p < 0.05) when given just prior to ischemia, but had no neuroprotective activity when given 30 min after the onset of ischemia. This short therapeutic window for MK-801 suggests that NMDA receptors play only a transient role in reversible focal ischemia in rats.


1991 ◽  
Vol 11 (6) ◽  
pp. 1025-1030 ◽  
Author(s):  
Yoshio Izumi ◽  
Simon Roussel ◽  
Elisabeth Pinard ◽  
Jacques Seylaz

The effects of magnesium, an endogenous inhibitor of calcium entry into neurons, upon ischemic brain damage were investigated using a well-characterized model of focal cerebral ischemia in rats. Infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride transcardiac perfusion 48 h after middle cerebral artery (MCA) occlusion. The area of ischemic damage was quantified by image analysis in coronal sections taken every 0.5 mm. MgCl2 (1 mmol/kg) was injected intraperitoneally just after MCA occlusion and again 1 h later. Posttreatment with MgCl2 (16 control and 16 treated rats) significantly reduced the cortical infarct volume. Compensation for the hyperglycemic effect of MgCl2 with insulin (17 rats) further reduced the infarct volume in the neocortex. No systemic effects of either treatment could account for the observed neuroprotection.


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