scholarly journals Adenosine kinase determines the degree of brain injury after ischemic stroke in mice

2011 ◽  
Vol 31 (7) ◽  
pp. 1648-1659 ◽  
Author(s):  
Hai-Ying Shen ◽  
Theresa A Lusardi ◽  
Rebecca L Williams-Karnesky ◽  
Jing-Quan Lan ◽  
David J Poulsen ◽  
...  

Adenosine kinase (ADK) is the major negative metabolic regulator of the endogenous neuroprotectant and homeostatic bioenergetic network regulator adenosine. We used three independent experimental approaches to determine the role of ADK as a molecular target for predicting the brain's susceptibility to ischemic stroke. First, when subjected to a middle cerebral artery occlusion model of focal cerebral ischemia, transgenic fb-Adk-def mice, which have increased ADK expression in striatum (164%) and reduced ADK expression in cortical forebrain (65%), demonstrate increased striatal infarct volume (126%) but almost complete protection of cortex (27%) compared with wild-type (WT) controls, indicating that cerebral injury levels directly correlate to levels of ADK in the CNS. Second, we demonstrate abrogation of lipopolysaccharide (LPS)-induced ischemic preconditioning in transgenic mice with brain-wide ADK overexpression (Adk-tg), indicating that ADK activity negatively regulates LPS-induced tolerance to stroke. Third, using adeno-associated virus-based vectors that carry Adk-sense or -antisense constructs to overexpress or knockdown ADK in vivo, we demonstrate increased (126%) or decreased (51%) infarct volume, respectively, 4 weeks after injection into the striatum of WT mice. Together, our data define ADK as a possible therapeutic target for modulating the degree of stroke-induced brain injury.

2002 ◽  
Vol 22 (2) ◽  
pp. 161-170 ◽  
Author(s):  
Michiko Nakamura ◽  
Kazuhiko Nakakimura ◽  
Mishiya Matsumoto ◽  
Takefumi Sakabe

Two types of ischemic tolerance in the brain, rapid and delayed, have been reported in terms of the interval between the conditioning and test insults. Although many reports showed that delayed-phase neuroprotection evoked by preconditioning is evident after 1 week or longer, there have been a few investigations about rapidly induced tolerance, and the reported neuroprotective effects become ambiguous 7 days after the insults. The authors examined whether this rapid ischemic tolerance exists after 7 days of reperfusion in a rat focal ischemic model, and investigated modulating effects of the adenosine A1 receptor antagonist DPCPX (8-cyclopentyl-1,3-dipropylxanthine). Preconditioning with 30 minutes of middle cerebral artery occlusion reduced infarct volume 7 days after 180 minutes of subsequent focal ischemia given after 1-hour reperfusion. The rapid preconditioning also improved neurologic outcome. These beneficial effects were attenuated by pretreatment of 0.1 mg/kg DPCPX, which did not influence the infarct volume after conditioning (30 minutes) or test (180 minutes) ischemia when given alone. The results show that preconditioning with a brief focal ischemia induces rapid tolerance to a subsequent severe ischemic insult, the effect of which is still present after 7 days of reperfusion, and that the rapid ischemic tolerance is possibly mediated through an adenosine A1 receptor–related mechanism.


2013 ◽  
Vol 33 (11) ◽  
pp. e1-e7 ◽  
Author(s):  
Brad A Sutherland ◽  
Alastair M Buchan

Recanalization of an occluded vessel with recombinant tissue plasminogen activator is an effective strategy for treating acute ischemic stroke. Recombinant tissue plasminogen activator is administered as alteplase, a formulation containing many excipients including L-arginine, the substrate for nitric oxide production. Most studies fail to compare the effects of alteplase on brain injury to its L-arginine carrier solution. This study aimed to verify the previously reported detrimental effects of alteplase after cerebral ischemia and delineate the contribution of L-arginine. Male Wistar rats, subjected to 90 minutes of intraluminal middle cerebral artery occlusion (MCAO), were administered alteplase, the carrier solution or saline upon reperfusion. Neither alteplase nor the carrier affected cerebral blood flow (CBF) restoration throughout the first 60 minutes of reperfusion. Alteplase treatment was associated with increased mortality after MCAO. Twenty-four hours after MCAO, neurologic function and infarct volume did not differ between rats treated with alteplase, the carrier solution, or saline. Irrespective of treatment group, infarct volume was correlated with CBF during reperfusion, neuroscore, and peri-infarct depolarizations. These results suggest that alteplase treatment, independent of thrombolysis, does not cause increased ischemic injury compared with its appropriate carrier solution, supporting the continued use of alteplase in eligible ischemic stroke patients.


2019 ◽  
Vol 11 (5) ◽  
pp. 983-1000 ◽  
Author(s):  
Shu-Na Wang ◽  
Zhi Wang ◽  
Tian-Ying Xu ◽  
Ming-He Cheng ◽  
Wen-Lin Li ◽  
...  

AbstractStroke is the second leading cause of death and main cause of disability worldwide, but with few effective therapies. Although stem cell-based therapy has been proposed as an exciting regenerative medicine strategy for brain injury, there are limitations. The developed cerebral organoids (COs) represent a promising transplantation source for stroke that remains to be answered. Here, we transplanted COs at 55 days and explored the feasibility in the rat middle cerebral artery occlusion (MCAO) model of stroke. COs transplantation at 6 h or even 24 h after MCAO significantly reduces brain infarct volume and improves neurological motor function. Transplanted COs show the potential of multilineage differentiation to mimic in vivo cortical development, support motor cortex region-specific reconstruction, form neurotransmitter-related neurons, and achieve synaptic connection with host brain via in situ differentiation and cell replacement in stroke. Cells from transplanted COs show extensive migration into different brain regions along corpus callosum. The mechanisms underlying COs transplantation therapy are also associated with enhanced neurogenesis, synaptic reconstruction, axonal regeneration and angiogenesis, and decreased neural apoptosis with more survival neurons after stroke. Moreover, COs transplantation promotes predominantly exogenous neurogenesis in the transplantation periphery of ipsilateral cortex and predominantly endogenous neurogenesis in the hippocampus and subventricular zone. Together, we demonstrate the efficacy and underlying mechanisms of COs transplantation in stroke. This preliminary but promising study provides first-hand preclinical evidence for COs transplantation as a potential and effective intervention for stroke treatment.


2004 ◽  
Vol 24 (6) ◽  
pp. 668-676 ◽  
Author(s):  
Hiroharu Kataoka ◽  
Seong-Woong Kim ◽  
Nikolaus Plesnila

The contribution of leukocyte infiltration to brain damage after permanent focal cerebral ischemia and the underlying molecular mechanisms are still unclear. Therefore, the aim of this study was to establish a mouse model for the visualization of leukocytes in the cerebral microcirculation in vivo and to investigate leukocyte-endothelial interaction (LEI) after permanent middle cerebral artery occlusion (MCAO). Sham-operated 129/Sv mice showed physiologic LEI in pial venules as observed by intravital fluorescent microscopy. Permanent focal cerebral ischemia induced a significant increase of LEI predominantly in pial venules. The number of rolling and adherent leukocytes reached 36.5 ± 13.2/100 μm × min and 22.5 ± 7.9/100 μm × min, respectively at 120 minutes after MCAO ( P = 0.016 vs. control). Of note, rolling and adherent leukocytes were also observed in arterioles of ischemic animals (7.3 ± 3.0/100 μm × min rolling and 3.0 ± 3.6/100 μm × min adherent). Capillary density was not different between groups. These results demonstrate that leukocytes accumulate in the brain not only after transient but also after permanent focal cerebral ischemia and may therefore contribute to brain damage after stroke without reperfusion.


2021 ◽  
Author(s):  
Qi Zhang ◽  
Chang Liu ◽  
Rubing Shi ◽  
Huimin Shan ◽  
Lidong Deng ◽  
...  

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.


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.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 259-259
Author(s):  
Bing-Qiao Zhao ◽  
Anil kumar Chauhan ◽  
Ian S. Patten ◽  
Michael Dockal ◽  
Friedrich Scheiflinger ◽  
...  

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&lt;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.


2017 ◽  
Vol 39 (6) ◽  
pp. 1005-1014 ◽  
Author(s):  
James E Orfila ◽  
Himmat Grewal ◽  
Robert M Dietz ◽  
Frank Strnad ◽  
Takeru Shimizu ◽  
...  

The current study focuses on the ability to improve cognitive function after stroke with interventions administered at delayed/chronic time points. In light of recent studies demonstrating delayed GABA antagonists improve motor function, we utilized electrophysiology, biochemistry and neurobehavioral methods to investigate the role of α5 GABAA receptors on hippocampal plasticity and functional recovery following ischemic stroke. Male C57Bl/6 mice were exposed to 45 min transient middle cerebral artery occlusion and analysis of synaptic and functional deficits performed 7 or 30 days after recovery. Our findings indicate that hippocampal long-term potentiation (LTP) is impaired 7 days after stroke and remain impaired for at least 30 days. We demonstrate that ex vivo administration of L655,708 reversed ischemia-induced plasticity deficits and importantly, in vivo administration at delayed time-points reversed stroke-induced memory deficits. Western blot analysis of hippocampal tissue reveals proteins responsible for GABA synthesis are upregulated (GAD65/67 and MAOB), increasing GABA in hippocampal interneurons 30 days after stroke. Thus, our data indicate that both synaptic plasticity and memory impairments observed after stroke are caused by excessive tonic GABA activity, making inhibition of specific GABA activity at delayed timepoints a potential therapeutic approach to improve functional recovery and reverse cognitive impairments after stroke.


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