scholarly journals Sirt1 Mediates Improvement in Cognitive Defects Induced by Focal Cerebral Ischemia Following Hyperbaric Oxygen Preconditioning in Rats

2017 ◽  
pp. 1029-1039 ◽  
Author(s):  
P. DING ◽  
D. REN ◽  
S. HE ◽  
M. HE ◽  
G. ZHANG ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Hyperbaric Oxygen ◽  
Cognitive Deficits ◽  
Focal Cerebral Ischemia ◽  
Ischemia Reperfusion ◽  
Artery Occlusion ◽  
Beneficial Effects ◽  
Mechanistic Basis ◽  
Hyperbaric Oxygen Preconditioning

Hyperbaric oxygen preconditioning (HBO-PC) has been proposed as a safe and practical approach for neuroprotection in ischemic stroke. However, it is not known whether HPO-PC can improve cognitive deficits induced by cerebral ischemia, and the mechanistic basis for any beneficial effects remains unclear. We addressed this in the present study using rats subjected to middle cerebral artery occlusion (MCAO) as an ischemic stroke model following HBO-PC. Cognitive function and expression of phosphorylated neurofilament heavy polypeptide (pNF-H) and doublecortin (DCX) in the hippocampus were evaluated 14 days after reperfusion and after short interfering RNA-mediated knockdown of sirtuin1 (Sirt1). HBO-PC increased pNF-H and DCX expression and mitigated cognitive deficits in MCAO rats. However, these effects were abolished by Sirt1 knockdown. Our results suggest that HBO-PC can protect the brain from injury caused by ischemia-reperfusion and that Sirt1 is a potential molecular target for therapeutic approaches designed to minimize cognitive deficits caused by cerebral ischemia.

scholarly journals Up-regulation of miR-499a-5p decreases cerebral ischemia/reperfusion injury by targeting PDCD4

2021 ◽  
Author(s):  
Weifeng Shan ◽  
Huifeng Ge ◽  
Bingquan Chen ◽  
Linger Huang ◽  
Shaojun Zhu ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Cell Model ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Tunel Staining ◽  
Cerebral Ischemia Reperfusion

Abstract MiR-499a-5p was significantly down-regulated in degenerative tissues and correlated with apoptosis. Nonetheless, the biological function of miR-499a-5p in acute ischemic stroke has been still unclear. In this study, we found the plasma levels of miR-499a-5p were significantly down-regulated in 64 ischemic stroke patients and negatively correlated with the National Institutes of Health Stroke Scale score. Then, we constructed cerebral ischemia/reperfusion (I/R) injury in rats after middle cerebral artery occlusion and subsequent reperfusion and oxygen-glucose deprivation and reoxygenation (OGD/R) treated SH-SY5Y cell model. Transfection with miR-499a-5p mimic was accomplished by intracerebroventricular injection in the in vivo I/R injury model. We further found miR-499a-5p overexpression decreased infarct volumes and cell apoptosis in the in vivo I/R stroke model using TTC and TUNEL staining. PDCD4 was a direct target of miR-499a-5p by luciferase report assay and western blotting. Knockdown of PDCD4 reduced the infarct damage and cortical neuron apoptosis caused by I/R injury. MiR-499a-5p exerted neuroprotective roles mainly through inhibiting PDCD4-mediated apoptosis by CCK-8 assay, LDH release assay and flow cytometry analysis. These findings suggest that miR-499a-5p might represent a novel target that regulates brain injury by inhibiting PDCD4-mediating apoptosis.

VWF-Cleaving Protease ADAMTS13 Reduces Brain Injury Following Ischemic Stroke in Mice: Essential Role for VWF in Stroke

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 259-259
Author(s):  
Bing-Qiao Zhao ◽  
Anil kumar Chauhan ◽  
Ian S. Patten ◽  
Michael Dockal ◽  
Friedrich Scheiflinger ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Essential Role ◽  
Focal Cerebral Ischemia ◽  
Infarct Volume ◽  
Recombinant Tissue Plasminogen Activator ◽  
Protective Role ◽  
Artery Occlusion ◽  
Type I ◽  
Deficient Mice

Abstract Ischemic stroke is the second leading cause of death and disability. The only approved therapy available is recombinant tissue plasminogen activator (tPA), but its use remains limited. Therefore, there is a need for an alternative drug. Platelets and their adhesion receptors play a crucial role in modulating infarct size during ischemic stroke. ADAMTS13 (A Disintegrin-like And Metalloprotease with Thrombospondin type I repeats-13) is a plasma metalloprotease that cleaves von Willebrand factor (VWF) an important adhesion molecule for platelets at sites of vascular injury. In patients, an increase in circulating levels of VWF and a decrease in ADAMTS13 activity are considered risk factors for ischemic stroke. By using genetically-modified mice we have previously shown that ADAMTS13 down regulates both thrombosis and inflammation and recombinant human ADAMTS13 down regulates platelet thrombi in injured arterioles. All these processes were dependent on VWF. We therefore hypothesize that ADAMTS13 has a protective role after ischemic stroke. In this study, we show that VWF deficiency or VWF heterozygosity in mice reduces infarct volume by two-fold after focal cerebral ischemia compared to wild-type (WT) in the middle cerebral artery occlusion (MCAO) stroke model. Furthermore, infusion of recombinant human VWF in WT mice not only accelerates thrombosis in the ferric-chloride injured artery model, but also increases infarct volume compared to vehicle-treated controls. These findings suggest an essential role of VWF in modulating infarction after stroke. We also show that ADAMTS13 deficiency in mice results in approximately 20% larger infarcts after cerebral ischemia compared to WT. The larger infarcts observed in ADAMTS13 deficient mice were due to VWF because mice deficient in both ADAMTS13 and VWF had infarct sizes similar to VWF deficient mice. Importantly, infusion of r-human ADAMTS13 immediately before reperfusion (two hour after occlusion) significantly reduced infarct volume (106.2 ± 9.7 mm3 vs 75.8 ± 6.9 mm3, P<0.05). Of note, we observed that ADAMTS13 protein was induced in the ischemic penumbra region of brain after ischemic stroke. Our findings reveal an important role for VWF in modulating infarct volume after ischemic stroke. In addition, recombinant-ADAMTS13 could become a new therapeutic agent for stroke therapy.

Delayed treatment with magnesium: reduction of brain infarction and improvement of electrophysiological recovery following transient focal cerebral ischemia in rats

2005 ◽  
Vol 102 (6) ◽  
pp. 1085-1093 ◽  
Author(s):  
E-Jian Lee ◽  
Ming-Yang Lee ◽  
Guan-Liang Chang ◽  
Li-Hsuan Chen ◽  
Yu-Ling Hu ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Focal Cerebral Ischemia ◽  
Ischemia Reperfusion ◽  
Brain Infarction ◽  
Artery Occlusion ◽  
Sprague Dawley ◽  
Content Type ◽  
Delayed Treatment ◽  
Cerebral Ischemia Reperfusion ◽  
Fine Print

Object. The authors examined whether delayed treatment with Mg++ would reduce brain infarction and improve electrophysiological and neurobehavioral recovery following cerebral ischemia—reperfusion. Methods. Male Sprague—Dawley rats were subjected to right middle cerebral artery occlusion for 90 minutes followed by 72 hours of reperfusion. Magnesium sulfate (750 µmol/kg) or vehicle was given via intracarotid infusion at the beginning of reperfusion. Neurobehavioral outcome and somatosensory evoked potentials (SSEPs) were examined before and 72 hours after ischemia—reperfusion. Brain infarction was assessed after the rats had died. Before ischemia—reperfusion, stable SSEP waveforms were recorded after individual fore- and hindpaw stimulations. At 72 hours of perfusion the SSEPs recorded from ischemic fore- and hindpaw cortical fields were depressed in vehicle-injected animals and the amplitudes decreased to 19 and 27% of baseline, respectively (p < 0.001). Relative to controls, the amplitudes of SSEPs recorded from both ischemic fore- and hindpaw cortical field in the Mg++-treated animals were significantly improved by 23% (p < 0.005) and 39% (p < 0.001) of baselines, respectively. In addition, Mg++ improved sensory and motor neurobehavioral outcomes by 34% (p < 0.01) and 24% (p < 0.05), respectively, and reduced cortical (p < 0.05) and striatal (p < 0.05) infarct sizes by 42 and 36%, respectively. Conclusions. Administration of Mg++ at the commencement of reperfusion enhances electrophysiological and neurobehavioral recovery and reduces brain infarction after cerebral ischemia—reperfusion. Because Mg++ has already been used clinically, it may be worthwhile to investigate it further to see if it holds potential benefits for patients with ischemic stroke and for those who will undergo carotid endarterectomy.

scholarly journals α2-Adrenoceptors do not Mediate Neuroprotection in Acute Ischemic Stroke in Mice

2011 ◽  
Vol 31 (10) ◽  
pp. e1-e7 ◽  
Author(s):  
Marc Brede ◽  
Stefan Braeuninger ◽  
Friederike Langhauser ◽  
Lutz Hein ◽  
Norbert Roewer ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Focal Cerebral Ischemia ◽  
Artery Occlusion ◽  
Experimental Stroke ◽  
Blood Pressure Lowering Effect ◽  
Α2 Adrenoceptors ◽  
Arterial Blood ◽  
Neuroprotective Function

We assessed the neuroprotective potential of α2-adrenoceptors in ischemic stroke using mice with targeted deletions of individual α2-adrenoceptor subtypes (α 2A−/−, α 2B−/−, α 2C−/−, α 2A/C−/−). The effects of the α2-adrenoceptor agonist clonidine were studied in parallel. Focal cerebral ischemia was induced with or without clonidine pretreatment by transient middle cerebral artery occlusion. Neurologic outcome and infarct volumes were evaluated on day 1. Cerebral blood flow (CBF) and mean arterial pressure were determined. α2- Adrenoceptor null mice did not display larger infarct volumes compared with wild-type (WT) mice under basal conditions ( P>0.05). In line with this finding, pretreatment with clonidine did not protect from ischemic brain damage in WT mice or α 2A−/−, α 2B−/−, and α 2C−/− mice. Clonidine induced smaller infarct volumes only in α 2A/C−/− mice ( P < 0.05), but this did not translate into improved neurologic function ( P > 0.05). Importantly, while clonidine caused a significant decrease in arterial blood pressure in all groups, it had no blood pressure lowering effect in α 2A/C−/− mice, and this correlated with higher CBF and smaller infarct volumes in this group. In summary, we could not demonstrate a neuroprotective function of α2-adrenoceptors in focal cerebral ischemia. Careful controlling of physiological parameters relevant for stroke outcome is recommended in experimental stroke studies.

scholarly journals Hemorrhagic Transformation and Microvascular Integrity during Focal Cerebral Ischemia/Reperfusion

1996 ◽  
Vol 16 (6) ◽  
pp. 1373-1378 ◽  
Author(s):  
Gerhard F. Hamann ◽  
Yasushi Okada ◽  
Gregory J. del Zoppo
Keyword(s):  
Cerebral Ischemia ◽  
Focal Cerebral Ischemia ◽  
Ischemia Reperfusion ◽  
Hemorrhagic Transformation ◽  
Artery Occlusion ◽  
Time Dependent ◽  
Adolescent Male ◽  
Blood Components ◽  
Cerebral Ischemia Reperfusion ◽  
Cerebral Artery Occlusion

Hemorrhagic transformation after cerebral ischemia is a well known clinical concern. The frequency of intact basal lamina (BL), identified by laminin antigen, in hemorrhagic and nonhemorrhagic zones after middle cerebral artery occlusion (MCA:O) and 3-h MCA:O with reperfusion in adolescent male baboons was assessed. Parenchymal hemoglobin was not detected prior to 24-h reperfusion. A significant decrease in the density of laminin (BL) in hemorrhagic zones (6.2 ± 2.4) compared with nonhemorrhagic ischemic zones (10.5 ± 2.4) (p < 0.05) and nonischemic basal ganglia (17.0 ± 2.7) (p < 0.01) was observed. Time-dependent changes in BL integrity appear linked to the extravasation of blood components.

scholarly journals The KCa3.1 Blocker TRAM-34 Reduces Infarction and Neurological Deficit in a Rat Model of Ischemia/Reperfusion Stroke

2011 ◽  
Vol 31 (12) ◽  
pp. 2363-2374 ◽  
Author(s):  
Yi-Je Chen ◽  
Girija Raman ◽  
Silke Bodendiek ◽  
Martha E O'Donnell ◽  
Heike Wulff
Keyword(s):  
Ischemic Stroke ◽  
Rat Model ◽  
Neurological Deficit ◽  
Ischemia Reperfusion ◽  
Artery Occlusion ◽  
Beneficial Effects ◽  
Inflammatory Damage ◽  
Male Wistar Rats ◽  
Cerebral Artery Occlusion ◽  
The Brain

Microglia and brain infiltrating macrophages significantly contribute to the secondary inflammatory damage in the wake of ischemic stroke. Here, we investigated whether inhibition of KCa3.1 (IKCa1/KCNN4), a calcium-activated K+ channel that is involved in microglia and macrophage activation and expression of which increases on microglia in the infarcted area, has beneficial effects in a rat model of ischemic stroke. Using an HPLC/MS assay, we first confirmed that our small molecule KCa3.1 blocker TRAM-34 effectively penetrates into the brain and achieves micromolar plasma and brain concentrations after intraperitoneal injection. Then, we subjected male Wistar rats to 90 minutes of middle cerebral artery occlusion (MCAO) and administered either vehicle or TRAM-34 (10 or 40 mg/kg intraperitoneally twice daily) for 7 days starting 12 hours after reperfusion. Both compound doses reduced infarct area by ∼50% as determined by hematoxylin & eosin staining on day 7 and the higher dose also significantly improved neurological deficit. We further observed a significant reduction in ED1+-activated microglia and TUNEL-positive neurons as well as increases in NeuN+ neurons in the infarcted hemisphere. Our findings suggest that KCa3.1 blockade constitutes an attractive approach for the treatment of ischemic stroke because it is still effective when initiated 12 hours after the insult.

scholarly journals Effect of combined therapy with hyperbaric oxygen and an antioxidant on infarct volume after permanent focal cerebral ischemia

2007 ◽  
pp. 369-373
Author(s):  
G Acka ◽  
A Sen ◽  
Z Canakci ◽  
S Yildiz ◽  
A Akin ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Hyperbaric Oxygen ◽  
Focal Cerebral Ischemia ◽  
Infarct Volume ◽  
Combined Therapy ◽  
Artery Occlusion ◽  
Control Group ◽  
Male Wistar Rats ◽  
Cerebral Artery Occlusion ◽  
Reduce Infarct Volume

The aim of the present study was to evaluate the efficiency of combination of hyperbaric oxygen (HBO) and an antioxidant on permanent focal cerebral ischemia. Male Wistar rats underwent permanent middle cerebral artery occlusion (MCAO). Then, animals were randomly assigned to one of four groups: the control group (n=9) received no treatment, HBO group (n=9) was treated for 90 min at 2.5 absolute atmosphere for 3 days, the U-74389G group (n=8) received single U-74389G injection (3 mg/kg), the HBO + U-74389G group (n=8) received both HBO and U-74389G treatments. Treatments were initiated within the first 10 min after MCAO. After 3 days, the infarct volumes in rat brains were measured. The infarct ratios were 25.6+/-6.5 % for the control group, 21.9+/-6.4 % for the HBO group, 15.7+/-5.7 % for U-74389G group and 12.5+/-3.8 % for HBO + U74389G group. The infarct volumes were significantly reduced in rats treated with U-74389G (p<0.05) and combination therapy (p<0.05). HBO failed to reduce infarct volume significantly. We concluded that 1) U-74389G is more beneficial than HBO on permanent MCAO in rats, and 2) a combined therapy failed to significantly improve infarct volume more than either single treatment.

Protective Effect of Capparis spinosa Extract Against Focal Cerebral Ischemia-Reperfusion Injury in Rats

2021 ◽  
Vol 21 ◽  
Author(s):  
Hassan Rakhshandeh ◽  
Samira Asgharzade ◽  
Mohammad Bagher Khorrami ◽  
Fatemeh Forouzanfar
Keyword(s):  
Oxidative Stress ◽  
Ischemic Stroke ◽  
Ischemia Reperfusion Injury ◽  
Focal Cerebral Ischemia ◽  
Infarct Volume ◽  
Ischemia Reperfusion ◽  
Public Health Problem ◽  
Artery Occlusion ◽  
Stroke Group ◽  
Capparis Spinosa

Background: Ischemic stroke is a serious public health problem. Despite extensive research focusing on the area, little is known about novel treatments. Objective: In this study, we aimed to investigate the effects of Capparis spinosa (C. spinosa) extract in the middle cerebral artery occlusion (MCAO) model of ischemic stroke. Methods: Wistar rats underwent 30-min MCAO-induced brain ischemia followed by 24 h of reperfusion. C. spinose was administrated orally once a day for 7 days before the induction of MCAO. The neurologic outcome, infarct volume (TTC staining), histological examination, and markers of oxidative stress, including total thiol content and malondialdehyde (MDA) levels, were measured 24 hr. after the termination of MCAO. Results: Pretreatment with C. spinosa, reduced neurological deficit score, histopathological alterations, and infarct volume in treated groups compared to stroke group. Furthermore, pretreatment with C. spinosa extract significantly reduced the level of MDA with concomitant increases in the levels of thiol in the brain tissues compared with the stroke group. Conclusion: Our study demonstrates that C. spinosa extract effectively protects MCAO injury through attenuation of suppressing oxidative stress.

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