Significant Contribution of Aortogenic Mechanism in Ischemic Stroke: In Vivo Observation of Aortic Plaque Rupture Dynamics by Angioscopy

2021 ◽  
Author(s):  
Yoshiharu Higuchi ◽  
Atsushi Hirayama ◽  
Yuma Hamanaka ◽  
Tomoaki Kobayashi ◽  
Yohei Sotomi ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Significant Contribution ◽  
Plaque Rupture ◽  
Aortic Plaque ◽  
Rupture Dynamics

scholarly journals Development of a photochemical thrombosis investigation system to obtain a rabbit ischemic stroke model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yoonhee Kim ◽  
Yoon Bum Lee ◽  
Seung Kuk Bae ◽  
Sung Suk Oh ◽  
Jong-ryul Choi
Keyword(s):  
Ischemic Stroke ◽  
Brain Damage ◽  
Rabbit Model ◽  
Specific Area ◽  
Brain Atlas ◽  
Rabbit Brain ◽  
Stroke Model ◽  
Triphenyltetrazolium Chloride ◽  
Induction System

AbstractPhotochemical thrombosis is a method for the induction of ischemic stroke in the cerebral cortex. It can generate localized ischemic infarcts in the desired region; therefore, it has been actively employed in establishing an ischemic stroke animal model and in vivo assays of diagnostic and therapeutic techniques for stroke. To establish a rabbit ischemic stroke model and overcome the shortcoming of previous studies that were difficult to build a standardized photothrombotic rabbit model, we developed a photochemical thrombosis induction system that can produce consistent brain damage on a specific area. To verify the generation of photothrombotic brain damage using the system, longitudinal magnetic resonance imaging, 2,3,5-triphenyltetrazolium chloride staining, and histological staining were applied. These analytical methods have a high correlation for ischemic infarction and are appropriate for analyzing photothrombotic brain damage in the rabbit brain. The results indicated that the photothrombosis induction system has a main advantage of being accurately controlled a targeted region of photothrombosis and can produce cerebral hemisphere lesions on the target region of the rabbit brain. In conjugation with brain atlas, it can induce photochemical ischemic stroke locally in the part of the brain that is responsible for a particular brain function and the system can be used to develop animal models with degraded specific functions. Also, the photochemical thrombosis induction system and a standardized rabbit ischemic stroke model that uses this system have the potential to be used for verifications of biomedical techniques for ischemic stroke at a preclinical stage in parallel with further performance improvements.

scholarly journals Nanoparticle Delivered Anti-miR-141-3p for Stroke Therapy

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1011
Author(s):  
Karishma Dhuri ◽  
Rutesh N. Vyas ◽  
Leslie Blumenfeld ◽  
Rajkumar Verma ◽  
Raman Bahal
Keyword(s):  
Ischemic Stroke ◽  
Nucleic Acid ◽  
Double Emulsion ◽  
Artery Occlusion ◽  
Brain Parenchyma ◽  
Confocal Imaging ◽  
In Vivo Studies ◽  
Stroke Therapy ◽  
Systemic Delivery

Ischemic stroke and factors modifying ischemic stroke responses, such as social isolation, contribute to long-term disability worldwide. Several studies demonstrated that the aberrant levels of microRNAs contribute to ischemic stroke injury. In prior studies, we established that miR-141-3p increases after ischemic stroke and post-stroke isolation. Herein, we explored two different anti-miR oligonucleotides; peptide nucleic acid (PNAs) and phosphorothioates (PS) for ischemic stroke therapy. We used US FDA approved biocompatible poly (lactic-co-glycolic acid) (PLGA)-based nanoparticle formulations for delivery. The PNA and PS anti-miRs were encapsulated in PLGA nanoparticles by double emulsion solvent evaporation technique. All the formulated nanoparticles showed uniform morphology, size, distribution, and surface charge density. Nanoparticles also exhibited a controlled nucleic acid release profile for 48 h. Further, we performed in vivo studies in the mouse model of ischemic stroke. Ischemic stroke was induced by transient (60 min) occlusion of middle cerebral artery occlusion followed by a reperfusion for 48 or 72 h. We assessed the blood-brain barrier permeability of PLGA NPs containing fluorophore (TAMRA) anti-miR probe after systemic delivery. Confocal imaging shows uptake of fluorophore tagged anti-miR in the brain parenchyma. Next, we evaluated the therapeutic efficacy after systemic delivery of nanoparticles containing PNA and PS anti-miR-141-3p in mice after stroke. Post-treatment differentially reduced both miR-141-3p levels in brain tissue and infarct injury. We noted PNA-based anti-miR showed superior efficacy compared to PS-based anti-miR. Herein, we successfully established that nanoparticles encapsulating PNA or PS-based anti-miRs-141-3p probes could be used as a potential treatment for ischemic stroke.

Abstract 110: Carotid Plaque Instability is Associated with an Increase in the Serum Ratio of circularRNA-284 to microRNA-221

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Hernan Bazan ◽  
Ashton Brooks ◽  
Daniel Lightell ◽  
T. Cooper Woods
Keyword(s):  
Ischemic Stroke ◽  
Sensitivity And Specificity ◽  
Carotid Plaque ◽  
Plaque Rupture ◽  
Serum Levels ◽  
Circular Rna ◽  
Cerebrovascular Event ◽  
Asymptomatic Group ◽  
Plaque Instability ◽  
Non Coding Rnas

Introduction: Atherosclerotic cap thinning and plaque instability occur as a result of a decrease in vascular smooth muscle cell proliferation, which is partly regulated by alterations in the expression of non-coding RNAs in the arterial wall. We recently reported that miR-221 expression in the carotid plaque shoulder is reduced immediately following a carotid-related ischemic cerebrovascular event and returns to normal levels after seven days. We hypothesized that changes in the expression of non-coding RNAs within carotid plaques are reflected in the serum of asymptomatic and acutely symptomatic patients with carotid disease. Methods: Serum levels of microRNA (miR) -221 and a circular RNA with potential binding sites for miR-221 (circR-284), were measured using real-time polymerase chain reaction in 41 patients undergoing carotid endarterectomy. Patients were grouped into those who were asymptomatic and those with an acute ischemic cerebrovascular event within the previous 5 days (urgent). Results: miR-221 was significantly lower (0.25 ± 0.11 vs. 1.00 ± 0.31, p = 0.01) while circR-284 was significantly elevated (2.96 ± 1.16 vs. 1.00 ± 0.37, p = 0.06) in the serum of the urgent compared to the asymptomatic group. Serum levels of these RNAs alone did not exhibit favorable sensitivity and specificity for use as a biomarker indicative of carotid-related ischemic stroke. The ratio of serum circR-284:miR-221, however, was significantly elevated in the urgent group [11.7 ± 0.48 vs. 1.0 ± 0.6, p = 0.0002 (Figure, A)]. Furthermore, receiver operator curve analysis of circR-284:miR-221 ratio demonstrated favorable sensitivity and specificity (Figure, B) for detecting carotid plaque rupture and ischemic stroke. Conclusions: Increases in the ratio of serum circR-284:miR-221 has potential as a diagnostic biomarker of carotid-related ischemic stroke. This data also supports the use and development of functionally related pairs of circulating non-coding RNAs as biomarkers.

scholarly journals Cilengitide Inhibits Neovascularization in a Rabbit Abdominal Aortic Plaque Model by Impairing the VEGF Signaling

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Fawang Zhu ◽  
Shuai Yuan ◽  
Jing Li ◽  
Yun Mou ◽  
Zhiqiang Hu ◽  
...  
Keyword(s):  
Umbilical Vein ◽  
Tube Formation ◽  
Control Group ◽  
In Vitro Experiments ◽  
Aortic Plaque ◽  
Abdominal Aortic ◽  
Aortic Plaques ◽  
Different Doses

Background. Cilengitide is a selective αvβ3 and αvβ5 integrin inhibitor. We sought to investigate the effect of cilengitide on the neovascularization of abdominal aortic plaques in rabbits and explore its underlying antiangiogenic mechanism on human umbilical vein endothelial cells (HUVECs). Materials and Methods. For the in vivo experiment, the abdominal aortic plaque model of rabbits was established and injected with different doses of cilengitide or saline for 14 consecutive days. Conventional ultrasound (CUS) and contrast-enhanced ultrasound (CEUS) were applied to measure the vascular structure and blood flow parameters. CD31 immunofluorescence staining was performed for examining neovascularization. Relative expressions of vascular endothelial growth factor (VEGF) and integrin of the plaque were determined. For in vitro experiments, HUVECs were tested for proliferation, migration, apoptosis, and tube formation in the presence of different doses of cilengitide. Relative expressions of VEGF, integrin, and Ras/ERK/AKT signaling pathways were determined for the exploration of underlying mechanism. Results. CEUS showed modestly increased size and eccentricity index (EI) of plaques in the control group. Different degrees of reduced size and EI of plaques were observed in two cilengitide treatment groups. The expressions of VEGF and integrin in the plaque were inhibited after 14 days of cilengitide treatment. The neovascularization and apoptosis of the abdominal aorta were also significantly alleviated by cilengitide treatment. For in vitro experiments, cilengitide treatment was found to inhibit the proliferation, migration, and tube formation of HUVECs. However, cilengitide did not induce the apoptosis of HUVECs. A higher dose of cilengitide inhibited the mRNA expression of VEGF-A, β3, and β5, but not αV. Lastly, cilengitide treatment significantly inhibited the Ras/ERK/AKT pathway in the HUVECs. Conclusions. This study showed that cilengitide effectively inhibited the growth of plaque size by inhibiting the angiogenesis of the abdominal aortic plaques and blocking the VEGF-mediated angiogenic effect on HUVECs.

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.

scholarly journals Discovery of Potential Anti-Ischemic Stroke Agents Through Inhibiting Sulfonylurea Receptor 1 (SUR1): A Pharmacophore-based Screening, Docking, and Molecular Dynamic Simulation

2021 ◽  
Vol 12 (5) ◽  
pp. 6915-6932
Keyword(s):  
Ischemic Stroke ◽  
Molecular Dynamic Simulation ◽  
Molecular Dynamic ◽  
Dynamic Simulation ◽  
Sulfonylurea Receptor ◽  
Brain Membrane ◽  
Simulation Based ◽  
Intact Brain ◽  
Docking Energy

Stroke is the leading cause of disability and death worldwide. Inhibition of sulfonylurea 1 receptor (SUR1) using glibenclamide previously has been studied in CNS ischemic tissues and faster recovery from stroke injury in different animal models of stroke. Unfortunately, glibenclamide cannot enter the brain through an intact brain membrane (BBB) due to its ionization at physiological pH. Therefore, it was hypothesized that compounds with structural properties similar to glibenclamide but with the ability to penetrate through BBB would be superior to glibenclamide in ischemic stroke. Docking energy and interactions of glibenclamide with SUR1 active site were assessed using AutoDock Vina. NCI databases search engines with limitations for penetration to CNS were used to find the best compounds with desired properties. Then two selected compounds were assessed with dynamic molecular studies. Two compounds called CID-415537 and CID-419074 with docking energies of -10.3 kcal/mol and -11 kcal/mol were identified. CID-415537 was selected as the best compound due to its proper interactions with SUR1 amino acids and stability in molecular dynamic simulation. Based on this study, compound CID-415537 would be a good candidate for a SUR1 inhibitor in ischemic stroke. However, further in vivo investigations are required to confirm these findings.

scholarly journals Identifying stroke therapeutics from preclinical models: A protocol for a novel application of network meta-analysis

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 11 ◽  
Author(s):  
Manoj M. Lalu ◽  
Dean A. Fergusson ◽  
Wei Cheng ◽  
Marc T. Avey ◽  
Dale Corbett ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Burden Of Illness ◽  
Evidence Synthesis ◽  
Meta Analysis ◽  
Synthesis Methods ◽  
Preclinical Models ◽  
Ovid Medline ◽  
Scientific Meetings ◽  
Ischemia Testing

Introduction: Globally, stroke is the second leading cause of death. Despite the burden of illness and death, few acute interventions are available to patients with ischemic stroke. Over 1,000 potential neuroprotective therapeutics have been evaluated in preclinical models. It is important to use robust evidence synthesis methods to appropriately assess which therapies should be translated to the clinical setting for evaluation in human studies. This protocol details planned methods to conduct a systematic review to identify and appraise eligible studies and to use a network meta-analysis to synthesize available evidence to answer the following questions: in preclinical in vivo models of focal ischemic stroke, what are the relative benefits of competing therapies tested in combination with the gold standard treatment alteplase in (i) reducing cerebral infarction size, and (ii) improving neurobehavioural outcomes? Methods: We will search Ovid Medline and Embase for articles on the effects of combination therapies with alteplase. Controlled comparison studies of preclinical in vivo models of experimentally induced focal ischemia testing the efficacy of therapies with alteplase versus alteplase alone will be identified. Outcomes to be extracted include infarct size (primary outcome) and neurobehavioural measures. Risk of bias and construct validity will be assessed using tools appropriate for preclinical studies. Here we describe steps undertaken to perform preclinical network meta-analysis to synthesise all evidence for each outcome and obtain a comprehensive ranking of all treatments. This will be a novel use of this evidence synthesis approach in stroke medicine to assess pre-clinical therapeutics. Combining all evidence to simultaneously compare mutliple therapuetics tested preclinically may provide a rationale for the clinical translation of therapeutics for patients with ischemic stroke.  Dissemination: Review findings will be submitted to a peer-reviewed journal and presented at relevant scientific meetings to promote knowledge transfer. Registration: PROSPERO number to be submitted following peer review.

scholarly journals Non-Invasive Multimodality Imaging Directly Shows TRPM4 Inhibition Ameliorates Stroke Reperfusion Injury

2018 ◽  
Vol 10 (1) ◽  
pp. 91-103 ◽  
Author(s):  
Bo Chen ◽  
Gandi Ng ◽  
Yahui Gao ◽  
See Wee Low ◽  
Edwin Sandanaraj ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Transient Receptor Potential ◽  
Multimodality Imaging ◽  
Infarct Volume ◽  
Triphenyltetrazolium Chloride ◽  
In Vivo Evaluation ◽  
Transient Receptor Potential Melastatin ◽  
Imaging Results ◽  
Trpm4 Channel

Abstract The transient receptor potential melastatin 4 (TRPM4) channel has been suggested to play a key role in the treatment of ischemic stroke. However, in vivo evaluation of TRPM4 channel, in particular by direct channel suppression, is lacking. In this study, we used multimodal imaging to assess edema formation and quantify the amount of metabolically functional brain salvaged after a rat model of stroke reperfusion. TRPM4 upregulation in endothelium emerges as early as 2 h post-stroke induction. Expression of TRPM4 channel was suppressed directly in vivo by treatment with siRNA; scrambled siRNA was used as a control. T2-weighted MRI suggests that TRPM4 inhibition successfully reduces edema by 30% and concomitantly salvages functionally active brain, measured by 18F-FDG-PET. These in vivo imaging results correlate well with post-mortem 2,3,5-triphenyltetrazolium chloride (TTC) staining which exhibits a 34.9% reduction in infarct volume after siRNA treatment. Furthermore, in a permanent stroke model, large areas of brain tissue displayed both edema and significant reductions in metabolic activity which was not shown in transient models with or without TRPM4 inhibition, indicating that tissue salvaged by TRPM4 inhibition during stroke reperfusion may survive. Evans Blue extravasation and hemoglobin quantification in the ipsilateral hemisphere were greatly reduced, suggesting that TRPM4 inhibition can improve BBB integrity after ischemic stroke reperfusion. Our results support the use of TRPM4 blocker for early stroke reperfusion.

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