Abstract 3773: The Impact Of Reperfusion On Vasogenic Edema Following Middle Cerebral Artery Occlusion In Experimental Ischemia

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Gregory Christoforidis ◽  
Cameron Rink ◽  
Nitn Garg ◽  
Shahid Khan ◽  
Chandan Sen
Keyword(s):  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Infarct Volume ◽  
Vasogenic Edema ◽  
Canine Model ◽  
Artery Occlusion ◽  
Permanent Occlusion ◽  
Linear Fit ◽  
Cerebral Artery Occlusion ◽  
The Impact

Objective: In order to assess the impact of reperfusion on the degree of subsequent cerebral edema following cerebral ischemia, this work sought to compare 24 hour infarct volume progression between permanent and transient middle cerebral artery occlusion (MCAO) in a canine model. Methods: Using a previously published endovascular transient MCAO method, 5 mongrel canines underwent 1-hour transient MCAO and 5 underwent permanent MCAO. Model parameters were altered to result in varying infarct volumes. Magnetic resonanace imaging (MRI) (3T Achieva, Philips) was performed one hour and 24 hours following reperfusion as well as 60 minutes following permanent occlusion. Infarct volumes were calculated using a previously published threshold technique by two observers using 1 hour mean diffusivity (MD) maps and 24hour FLAIR MRI. Reproducibility was assessed using Bland-Altman statistic. Average infarct volumes between the observers were calculated. Bivariate linear fit analysis were used to assess the correlation between immediate and 24 hours infarct volume determinations. Results: R square (r2) for linear fit was 0.964 (p=0.0005) for permanent occlusion and 0.971 (p= 0.0022) for transient occlusion ( figure 1 ). The infarct volumes measured at 1 hour increased by a factor of 1.42 relative to 24 hour infarct volumes for permanent occlusion and 2.05 for transient occlusion. Bland-Altman statistic indicates that reproducibility using the MD maps (15.9%) and FLAIR images (13.3%) is not substantially different. None of the animals demonstrated hemorrhagic conversion by 24 hours. Conclusion: MD maps generated one hour post reperfusion following transient and permanent MCAO in a canine model can serve as a reliable assessment for infarct volume determination. Increase in infarct volume at 24 hours, presumably due to vasogenic edema, was greater in reperfused infarctions than with permanent occlusion. Figure 1: Bivariate linear fit analysis comparing immediate and 24-hour infarct volume calculations for permanent and transient occlusions.

scholarly journals Treadmill Training Effects on Neurological Outcome After Middle Cerebral Artery Occlusion in Rats

2003 ◽  
Vol 30 (3) ◽  
pp. 252-258 ◽  
Author(s):  
Yea-Ru Yang ◽  
Ray-Yau Wang ◽  
Paulus Shyi-Gang Wang ◽  
Shang-Ming Yu
Keyword(s):  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Neurological Outcome ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Treadmill Training ◽  
Neurological Score ◽  
Cerebral Artery Occlusion ◽  
The Impact

Background:Treadmill training is used for promoting rhythmical vigorous walking and for task-related training in patients with stroke. The neurological impact of treadmill training has not been established. The present investigation is aimed at (1) examining neurological changes over a four-week period after middle cerebral artery occlusion (MCAO) in rats and (2) assessing the impact of one-week, two-week and four-week treadmill training in MCAO rats.Methods:Male Sprague-Dawley rats were subjected to 60-minute right MCAO. All rats were randomly assigned to one of seven groups. Infarct volume and neurological score were measured.Results:Rats sacrificed 24 hours post MCAO had the largest infarct volumes (171.4 ± 14.4 mm3) and the highest neurological score (median: 2, range: 1-3). We noted that without treadmill training, infarct sizes and neurological score diminished with time. Treadmill training for at least one week further reduced infarct volume and significantly improved neurologic function in MCAO rats.Conclusion:Treadmill training after focal cerebral ischemia significantly improves neurological outcome in MCAO rats. Treadmill training may be beneficial for ischemic brain recovery.

MitoKATP opener, diazoxide, reduces neuronal damage after middle cerebral artery occlusion in the rat

2002 ◽  
Vol 283 (3) ◽  
pp. H1005-H1011 ◽  
Author(s):  
Katsuyoshi Shimizu ◽  
Zsombor Lacza ◽  
Nishadi Rajapakse ◽  
Takashi Horiguchi ◽  
James Snipes ◽  
...  
Keyword(s):  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Ischemia Reperfusion Injury ◽  
Neuronal Damage ◽  
Infarct Volume ◽  
Ischemia Reperfusion ◽  
Artery Occlusion ◽  
Sham Treatment ◽  
Cerebral Artery Occlusion

We investigated effects of diazoxide, a selective opener of mitochondrial ATP-sensitive K+ (mitoKATP) channels, against brain damage after middle cerebral artery occlusion (MCAO) in male Wistar rats. Diazoxide (0.4 or 2 mM in 30 μl saline) or saline (sham) was infused into the right lateral ventricle 15 min before MCAO. Neurological score was improved 24 h later in the animals treated with 2 mM diazoxide (13.8 ± 0.7, n = 13) compared with sham treatment (9.5 ± 0.2, n = 6, P < 0.01). The total percent infarct volume (MCAO vs. contralateral side) of sham treatment animals was 43.6 ± 3.6% ( n = 12). Treatment with 2 mM diazoxide reduced the infarct volume to 20.9 ± 4.8% ( n = 13, P < 0.05). Effects of diazoxide were prominent in the cerebral cortex. The protective effect of diazoxide was completely prevented by the pretreatment with 5-hydroxydecanoate (100 mM in 10 μl saline), a selective blocker of mitoKATP channels ( n = 6). These results indicate that selective opening of the mitoKATP channel has neuroprotective effects against ischemia-reperfusion injury in the rat brain.

Abstract 11511: Genetic Variation in Retinal Vascular Patterning Predicts Variation in Pial Collateral Extent and Infarct Volume After Middle Cerebral Artery Occlusion

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Pranay Prabhakar ◽  
Hua Zhang ◽  
De Chen ◽  
Stephen Lockett ◽  
James E Faber
Keyword(s):  
Genetic Variation ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Genetic Background ◽  
Infarct Volume ◽  
Indirect Evidence ◽  
Artery Occlusion ◽  
Stroke Severity ◽  
Cerebral Artery Occlusion

Introduction: The presence of a native (pre-existing) collateral circulation in tissues lessens injury in stroke and other occlusive diseases. However, differences in genetic background are accompanied by wide variation in the number and diameter (extent) of native collaterals in mice, resulting in large variation in protection. Indirect evidence suggests a similar wide variation also exists in humans. However, methods of measurement in humans are indirect, invasive and not widely available. Hypothesis: We sought to determine if differences in genetic background in mice result in variation in branch-patterning of the retinal circulation, and if these differences predict differences in collateral extent and, in turn, differences in severity of ischemic stroke. Methods: Patterning metrics were obtained for the retinal arterial trees of 10 mouse strains (n=8 per strain) that differ widely in collateral extent in brain and other tissues. We also obtained pial collateral number and diameter, and infarct volume 24h after permanent middle cerebral artery occlusion. Forward- and reverse-stepwise multivariate regression analysis was conducted and model performance assessed using K-fold cross-validation. Results: Twenty-one metrics varied significantly with genetic strain (p<0.01). Ten metrics (eg, vessel caliber, bifurcation angle, lacunarity, optimality, branch length) strongly predicted collateral number and diameter across 7 regression models. The best models closely predicted (p<0.0001) collateral number (K-fold R 2 =0.83-0.98), diameter (0.73-0.88) and infarct volume (0.85-0.87). Conclusions: Differences in retinal tree patterning are specified by genetic background and closely predict genetic variation in pial collateral extent and, in turn, stroke severity. If these findings can be confirmed in humans, and given that genetic variation in cerebral collaterals extends to other tissues at least in mice, a similar “retinal predictor index” could be developed as a biomarker for collateral extent in brain and other tissues. This could aid prediction of the risk-severity of tissue injury in occlusive disease as well as stratification of patients for treatment options and enrollment in clinical studies.

Blocking A1 astrocyte conversion with semaglutide attenuates blood-brain barrier disruption in mice after middle cerebral artery occlusion

2021 ◽  
Author(s):  
Qi Zhang ◽  
Chang Liu ◽  
Rubing Shi ◽  
Huimin Shan ◽  
Lidong Deng ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Middle Cerebral Artery ◽  
Signaling Pathways ◽  
Middle Cerebral Artery Occlusion ◽  
Blood Brain Barrier ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Rna Seq ◽  
Neurobehavioral Outcomes ◽  
Cerebral Artery Occlusion

Abstract Background Astrocytes play an essential role in the modulation of blood-brain barrier function. Neurological diseases induce astrocytes to transform into a neurotoxic A1 phenotype, thus exacerbating brain injury. However, the effect of A1 astrocyte on the function of BBB after stroke is unknown. Method: Adult male ICR mice (n = 78) were subjected to 90-minute transient middle cerebral artery occlusion. Immunohistochemical staining of A1 (C3d) and A2 (S100A10) was performed to characterize phenotypic changes of astrocytes overtime after stroke. Glucagon-like peptide-1 receptor agonist semaglutide was intraperitoneally injected into the mice to inhibit A1 astrocyte. Infarct volume, atrophy volume, neurobehavioral outcomes, and BBB permeability were examined. RNA-seq was adopted to explore the potential targets and signaling pathways of A1 astrocytes induced BBB dysfunction. Results Astrocytes assumed the A2 phenotype at the early stage of ischemic stroke but gradually transformed to the A1 phenotype. Semaglutide treatment reduced M1 microglia polarization and A1 astrocytes conversion after ischemic stroke (p < 0.05). Ischemia induced brain infarct volume, atrophy volume and neuroinflammation were reduced in the semaglutide treated mice. Neurobehavioral outcomes were improved compared to the control mice (p < 0.05). Further study demonstrated that semaglutide treatment reduced the gap formation of tight junction proteins ZO-1, claudin-5 and occludin, as well as IgG leakage following three days of ischemic stroke (p < 0.05). In vitro experiments revealed that A1 astrocyte-conditioned medium disrupted BBB integrity. RNA-seq further showed that A1 astrocytes were enriched in inflammatory factors and chemokines, as well as significantly modulating TNF and chemokine signaling pathways, which are closely related to barrier damage. Conclusion We concluded that astrocytes undergo a conversion from A2 phenotype to A1 phenotype overtime after ischemic stroke. A1 astrocytes aggravated BBB disruption, suggesting that block of A1 astrocytes conversion provides a novel strategy for the treatment of ischemic stroke.

Melatonin and calpeptin synergistically protect against post-reperfusion injury in a rat middle cerebral artery occlusion stroke model

2021 ◽  
Vol 4 (4) ◽  
pp. 592-612
Author(s):  
Ye Feng ◽  
Qian Xu ◽  
Raymond Tak Fai Cheung
Keyword(s):  
Cerebral Ischemia ◽  
Middle Cerebral Artery ◽  
Reperfusion Injury ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Neurological Deficit ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Stroke Model ◽  
Cerebral Artery Occlusion

Cerebral ischemia induces oxidative injury and increases the intracellular calcium ion concentration to activate several calcium-dependent proteases such as calpains. Calpain activation leads to various necrotic and apoptotic processes. Calpeptin is a potent, cell-permeable calpain inhibitor. As a strong antioxidant and free radical scavenger, melatonin shows beneficial effect in rodent models of focal cerebral ischemia when given prior to ischemia or reperfusion. This study was focused on the neuroprotective effects of melatonin and/or calpeptin given after onset of reperfusion. For this purpose, right-sided middle cerebral artery occlusion (MCAO) for 90 minutes followed by 24 or 72 hours of reperfusion was performed in male Sprague Dawley rats, then, melatonin 50 or 150 µg/kg, calpeptin 10, 15 or 50 µg/kg or a combination of melatonin 50 µg/kg plus calpeptin 15 or 50 µg/kg were injected via an intracerebroventricular route at 15 minutes after onset of reperfusion. Melatonin or calpeptin tended to reduce the relative infarct volume and significantly decreased the neurological deficit at 24 hours. The combination achieved a greater protection than each of them alone. Melatonin, calpeptin or the combination all decreased Fluoro-Jade B (FJB)+ degenerative neurons and cleaved/total caspase-3 ratio at 24 hours. These treatments did not significantly impact the density of surviving neurons and ED-1+ macrophage/activated microglia. At the 72-hour-reperfusion, melatonin or the combination decreased the relative infarct volume and neurological deficit. Nevertheless, only the combination reduced FJB+ degenerating neurons at 72 hours. In conclusion, a combination of melatonin and calpeptin exerted synergistic protection against post-reperfusion injury in a rat MCAO stroke model.

Demonstration of therapeutic window of Cerebrolysin in embolic stroke: A prospective, randomized, blinded, and placebo-controlled study

2017 ◽  
Vol 12 (6) ◽  
pp. 628-635 ◽  
Author(s):  
Li Zhang ◽  
Michael Chopp ◽  
Mei Lu ◽  
Talan Zhang ◽  
Chao Li ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Mean Difference ◽  
Embolic Stroke ◽  
Therapeutic Window ◽  
Cerebral Artery Occlusion

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.

scholarly journals Inhibition of MicroRNA-383 Ameliorates Injury After Focal Cerebral Ischemia via Targeting PPARγ

2016 ◽  
Vol 39 (4) ◽  
pp. 1339-1346 ◽  
Author(s):  
Lichun Pei ◽  
Songyan Meng ◽  
Weigang Yu ◽  
Qiujun Wang ◽  
Fangfang Song ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Protein Level ◽  
Focal Cerebral Ischemia ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Luciferase Assay ◽  
Cerebral Artery Occlusion

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.

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