scholarly journals Role of long noncoding RNA MEG3/miR-378/GRB2 axis in neuronal autophagy and neurological functional impairment in ischemic stroke

2020 ◽  
Vol 295 (41) ◽  
pp. 14125-14139 ◽  
Author(s):  
Hong-Cheng Luo ◽  
Ting-Zhuang Yi ◽  
Fu-Gao Huang ◽  
Ying Wei ◽  
Xiao-Peng Luo ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Functional Impairment ◽  
Molecular Mechanisms ◽  
Glucose Deprivation ◽  
Oxygen Glucose Deprivation ◽  
Neuronal Autophagy

Autophagy has been shown to maintain neural system homeostasis during stroke. However, the molecular mechanisms underlying neuronal autophagy in ischemic stroke remain poorly understood. This study aims to investigate the regulatory mechanisms of the pathway consisting of MEG3 (maternally expressed gene 3), microRNA-378 (miR-378), and GRB2 (growth factor receptor-bound protein 2) in neuronal autophagy and neurological functional impairment in ischemic stroke. A mouse model of the middle cerebral artery occluded–induced ischemic stroke and an in vitro model of oxygen-glucose deprivation–induced neuronal injury were developed. To understand the role of the MEG3/miR-378/GRB2 axis in the neuronal regulation, the expression of proteins associated with autophagy in neurons was measured by Western blotting analysis, and neuron death was evaluated using a lactate dehydrogenase leakage rate test. First, it was found that the GRB2 gene, up-regulated in middle cerebral artery occluded–operated mice and oxygen-glucose deprivation–exposed neurons, was a target gene of miR-378. Next, miR-378 inhibited neuronal loss and neurological functional impairment in mice, as well as neuronal autophagy and neuronal death by silencing of GRB2. Confirmatory in vitro experiments showed that MEG3 could specifically bind to miR-378 and subsequently up-regulate the expression of GRB2, which in turn suppressed the activation of Akt/mTOR pathway. Taken together, these findings suggested that miR-378 might protect against neuronal autophagy and neurological functional impairment and proposed that a MEG3/miR-378/GRB2 regulatory axis contributed to better understanding of the pathophysiology of ischemic stroke.

Abstract WP430: Endothelial Cell Collection from Ipsilateral Middle Cerebral Artery in Acute Ischemic Stroke

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Sunil A Sheth ◽  
Abhishek Verma ◽  
David S Liebeskind ◽  
Jeffrey L Saver ◽  
Gary Duckwiler ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Endothelial Cell ◽  
Middle Cerebral Artery ◽  
Acute Ischemic Stroke ◽  
Cerebral Artery ◽  
Critical Role ◽  
Early Time ◽  
Stent Retriever ◽  
Positive Controls

Introduction: The cerebrovascular endothelium plays a critical role in the pathogenesis of and response to acute ischemic stroke (AIS). To date, techniques to study its function have relied on animal and in vitro models. A robust method of endothelial cell (EC) capture in patients with AIS at early time points, from within the ischemic region, could greatly advance our understanding of cerebrovascular injury. Method: Patients undergoing thrombectomy for middle cerebral artery occlusion (MCA) within 8 hours of onset were offered enrollment if the pass of their stent-retriever device occurred directly into a distal access catheter in the proximal M1 segment, limiting exposure of the device to only the MCA. After retrieval, ECs adherent to the devices were retrieved and stained for EC (CD31) and leukocyte (CD45) markers. EC identity and yield were confirmed by flow cytometry with simultaneous immuno-fluorescence microscopy. Cultured human ECs were used as positive controls. The EC fraction was defined as CD31 + CD45 - with size and morphological features consistent with the positive controls. Results: ECs from stent-retriever devices (n=3) were collected and pooled. Approximately 8% of the collected cells represented ECs. EC collected from the stent-retrievers demonstrated highly similar shape, morphology and antibody staining patterns compared to the positive controls (Figure). Conclusions: Here we provide the first demonstration of a rapid post-thrombectomy method for reliable harvesting of cerebral ECs in humans. The ability to capture these cells in patients with AIS within hours of symptom onset opens many avenues of exploration for determining the role of ECs in AIS.

scholarly journals Upregulation of miR-216a exerts neuroprotective effects against ischemic injury through negatively regulating JAK2/STAT3-involved apoptosis and inflammatory pathways

2019 ◽  
Vol 130 (3) ◽  
pp. 977-988 ◽  
Author(s):  
Yu Shuang Tian ◽  
Di Zhong ◽  
Qing Qing Liu ◽  
Xiu Li Zhao ◽  
Hong Xue Sun ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Inflammatory Mediators ◽  
Neurological Deficit ◽  
Ischemic Injury ◽  
Glucose Deprivation ◽  
Luciferase Assay ◽  
Oxygen Glucose Deprivation ◽  
Tnf Α

OBJECTIVEIschemic stroke remains a significant cause of death and disability in industrialized nations. Janus tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) of the JAK2/STAT3 pathway play important roles in the downstream signal pathway regulation of ischemic stroke–related inflammatory neuronal damage. Recently, microRNAs (miRNAs) have emerged as major regulators in cerebral ischemic injury; therefore, the authors aimed to investigate the underlying molecular mechanism between miRNAs and ischemic stroke, which may provide potential therapeutic targets for ischemic stroke.METHODSThe JAK2- and JAK3-related miRNA (miR-135, miR-216a, and miR-433) expression levels were detected by real-time quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis in both oxygen-glucose deprivation (OGD)–treated primary cultured neuronal cells and mouse brain with middle cerebral artery occlusion (MCAO)–induced ischemic stroke. The miR-135, miR-216a, and miR-433 were determined by bioinformatics analysis that may target JAK2, and miR-216a was further confirmed by 3′ untranslated region (3′UTR) dual-luciferase assay. The study further detected cell apoptosis, the level of lactate dehydrogenase, and inflammatory mediators (inducible nitric oxide synthase [iNOS], matrix metalloproteinase–9 [MMP-9], tumor necrosis factor–α [TNF-α], and interleukin-1β [IL-1β]) after cells were transfected with miR-NC (miRNA negative control) or miR-216a mimics and subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) damage with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, annexin V–FITC/PI, Western blots, and enzyme-linked immunosorbent assay detection. Furthermore, neurological deficit detection and neurological behavior grading were performed to determine the infarction area and neurological deficits.RESULTSJAK2 showed its highest level while miR-216a showed its lowest level at day 1 after ischemic reperfusion. However, miR-135 and miR-433 had no obvious change during the process. The luciferase assay data further confirmed that miR-216a can directly target the 3′UTR of JAK2, and overexpression of miR-216a repressed JAK2 protein levels in OGD/R-treated neuronal cells as well as in the MCAO model ischemic region. In addition, overexpression of miR-216a mitigated cell apoptosis both in vitro and in vivo, which was consistent with the effect of knockdown of JAK2. Furthermore, the study found that miR-216a obviously inhibited the inflammatory mediators after OGD/R, including inflammatory enzymes (iNOS and MMP-9) and cytokines (TNF-α and IL-1β). Upregulating miR-216a levels reduced ischemic infarction and improved neurological deficit.CONCLUSIONSThese findings suggest that upregulation of miR-216a, which targets JAK2, could induce neuroprotection against ischemic injury in vitro and in vivo, which provides a potential therapeutic target for ischemic stroke.

scholarly journals Silencing of Long Noncoding RNA Nespas Aggravates Microglial Cell Death and Neuroinflammation in Ischemic Stroke

Stroke ◽  
2019 ◽  
Vol 50 (7) ◽  
pp. 1850-1858 ◽  
Author(s):  
Yiming Deng ◽  
Duanduan Chen ◽  
Luyao Wang ◽  
Feng Gao ◽  
Bo Jin ◽  
...  
Keyword(s):  
Cell Death ◽  
Ischemic Stroke ◽  
Middle Cerebral Artery ◽  
Long Noncoding Rna ◽  
Noncoding Rna ◽  
Noncoding Rnas ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Oxygen Glucose Deprivation ◽  
Cerebral Artery Occlusion

Background and Purpose— Ischemic stroke is one of the leading causes of morbidity and mortality worldwide and a major cause of long-term disability. Recently, long noncoding RNAs have been revealed, which are tightly associated with several human diseases. However, the functions of long noncoding RNAs in ischemic stroke still remain largely unknown. In the current study, for the first time, we investigated the role of long noncoding RNA Nespas in ischemic stroke. Methods— We used in vivo models of middle cerebral artery occlusion and in vitro models of oxygen-glucose deprivation to illustrate the effect of long noncoding RNA Nespas on ischemic stroke. Results— We found expression of Nespas was significantly increased in ischemic cerebral tissues and oxygen-glucose deprivation–treated BV2 cells in a time-dependent manner. Silencing of Nespas aggravated middle cerebral artery occlusion operation–induced IR injury and cell death. In addition, proinflammatory cytokine production and NF-κB (nuclear factor-κB) signaling activation were inhibited by Nespas overexpression. TAK1 (transforming growth factor-β–activated kinase 1) was found to directly interact with Nespas, and TAK1 activation was significantly suppressed by Nespas. At last, we found Nespas-inhibited TRIM8 (tripartite motif 8)-induced K63-linked polyubiquitination of TAK1. Conclusions— We showed that Nespas played anti-inflammatory and antiapoptotic roles in cultured microglial cells after oxygen-glucose deprivation stimulation and in mice after ischemic stroke by inhibiting TRIM8-related K63-linked polyubiquitination of TAK1.

Neuroprotective Effects of Propofol in Models of Cerebral Ischemia

2006 ◽  
Vol 104 (1) ◽  
pp. 80-89 ◽  
Author(s):  
Chiara Adembri ◽  
Luna Venturi ◽  
Alessia Tani ◽  
Alberto Chiarugi ◽  
Elena Gramigni ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Mitochondrial Swelling ◽  
Oxygen Glucose Deprivation ◽  
Neuroprotective Effects ◽  
Cerebral Artery Occlusion

Background Propofol (2,6-diisopropylphenol) has been shown to attenuate neuronal injury in a number of experimental conditions, but studies in models of cerebral ischemia have yielded conflicting results. Moreover, the mechanisms involved in its neuroprotective effects are yet unclear. Methods The authors evaluated the neuroprotective effects of propofol in rat organotypic hippocampal slices exposed to oxygen-glucose deprivation, an in vitro model of cerebral ischemia. To investigate its possible mechanism of action, the authors then examined whether propofol could reduce Ca2+-induced rat brain mitochondrial swelling, an index of mitochondrial membrane permeability, as well as the mitochondrial swelling evoked by oxygen-glucose deprivation in CA1 pyramidal cells by transmission electron microscopy. Finally, they evaluated whether propofol could attenuate the infarct size and improve the neurobehavioral outcome in rats subjected to permanent middle cerebral artery occlusion in vivo. Results When present in the incubation medium during oxygen-glucose deprivation and the subsequent 24 h recovery period, propofol (10-100 microM) attenuated CA1 injury in hippocampal slices in vitro. Ca2+-induced brain mitochondrial swelling was prevented by 30-100 microM propofol, and so were the ultrastructural mitochondrial changes in CA1 pyramidal cells exposed to oxygen-glucose deprivation. Twenty-four hours after permanent middle cerebral artery occlusion, propofol (100 mg/kg, intraperitoneal) reduced the infarct size by approximately 30% when administered immediately after and up to 30 min after the occlusion. Finally, propofol administered within 30 min after middle cerebral artery occlusion was unable to affect the global neurobehavioral score but significantly preserved spontaneous activity in ischemic rats. Conclusions These results show that propofol, at clinically relevant concentrations, is neuroprotective in models of cerebral ischemia in vitro and in vivo and that it may act by preventing the increase in neuronal mitochondrial swelling.

scholarly journals Neuroprotective and Angiogenesis Effects of Levetiracetam Following Ischemic Stroke in Rats

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiang Yao ◽  
Wenping Yang ◽  
Zhendong Ren ◽  
Haoran Zhang ◽  
Dafa Shi ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Ischemic Stroke ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Infarct Volume ◽  
Hypoxia Inducible Factor ◽  
Neuronal Cell ◽  
Anti Inflammatory

Objective: The present study explored whether levetiracetam (LEV) could protect against experimental brain ischemia and enhance angiogenesis in rats, and investigated the potential mechanisms in vivo and in vitro.Methods: The middle cerebral artery was occluded for 60 min to induce middle cerebral artery occlusion (MCAO). The Morris water maze was used to measure cognitive ability. The rotation test was used to assess locomotor function. T2-weighted MRI was used to assess infarct volume. The neuronal cells in the cortex area were stained with cresyl purple. The anti-inflammatory effects of LEV on microglia were observed by immunohistochemistry. Enzyme-linked immunosorbent assays (ELISA) were used to measure the production of pro-inflammatory cytokines. Western blotting was used to detect the levels of heat shock protein 70 (HSP70), vascular endothelial growth factor (VEGF), and hypoxia-inducible factor-1α (HIF-1α) in extracts from the ischemic cortex. Flow cytometry was used to observe the effect of LEV on neuronal cell apoptosis.Results: LEV treatment significantly increased the density of the surviving neurons in the cerebral cortex and reduced the infarct size (17.8 ± 3.3% vs. 12.9 ± 1.4%, p < 0.01) after MCAO. Concurrently, the time required to reach the platform for LEV-treated rats was shorter than that in the saline group on day 11 after MCAO (p < 0.01). LEV treatment prolonged the rotarod retention time on day 14 after MCAO (84.5 ± 6.7 s vs. 59.1 ± 6.2 s on day 14 compared with the saline-treated groups, p < 0.01). It also suppressed the activation of microglia and inhibited TNF-α and Il-1β in the ischemic brain (135.6 ± 5.2 pg/ml vs. 255.3 ± 12.5 pg/ml, 18.5 ± 1.3 pg/ml vs. 38.9 ± 2.3 pg/ml on day 14 compared with the saline-treated groups, p < 0.01). LEV treatment resulted in a significant increase in HIF-1α, VEGF, and HSP70 levels in extracts from the ischemic cerebral cortex. At the same time, LEV reduced neuronal cell cytotoxicity and apoptosis induced by an ischemic stroke (p < 0.01).Conclusion: LEV treatment promoted angiogenesis and functional recovery after cerebral ischemia in rats. These effects seem to be mediated through anti-inflammatory and antiapoptotic activities, as well as inducing the expression of HSP70, VEGF, and HIF-1α.

scholarly journals Non-survivor patients with malignant middle cerebral artery infarction showed persistently high serum malondialdehyde levels

BMC Neurology ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Leonardo Lorente ◽  
María M. Martín ◽  
Pedro Abreu-González ◽  
Rafael Sabatel ◽  
Luis Ramos ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Potential Role ◽  
High Serum ◽  
Mortality Prediction ◽  
Middle Cerebral Artery Infarction ◽  
Acute Infarction ◽  
New Findings

Abstract Objective Previously there have been found higher circulating malondialdehyde levels during the first week of ischemic stroke in patients with worst neurological functional outcome, and at moment of ischemic stroke in non-survivor patients. Thus, the aim of our study was to determine the potential role of serum malondialdehyde levels during the first week of a severe cerebral infarction to mortality prediction. Methods This study was observational, prospective, and multicenter. We included patients with a severe malignant middle cerebral artery infarction (MMCAI) defined as patients with computed tomography showing acute infarction in more than of 50% of the territory and Glasgow Coma Scale (GCS) lower than 9. We determined serum concentrations of malondialdehyde on days 1, 4 and 8 of MMCAI. Results Serum malondialdehyde concentrations at days 1 (p < 0.001), 4 (p < 0.001), and 8 (p = 0.001) of MMCAI in non-survivor patients (n = 34) were higher than in survivor patients (n = 34). ROC curve analyses showed that serum malondialdehyde concentrations at days 1, 4, and 8 of MMCAI had an AUC (95% CI) to predict 30-day mortality of 0.77 (0.65–0.86; p < 0.001), 0.82 (0.69–0.91; p < 0.001) and 0.84 (0.70–0.93; p < 0.001) respectively. Conclusions The new findings of our study were that serum malondialdehyde levels during the first week of MMCAI could be used as biomarkers to mortality prediction.

scholarly journals Interleukin 1 alpha administration is neuroprotective and neuro-restorative following experimental ischemic stroke

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Kathleen E. Salmeron ◽  
Michael E. Maniskas ◽  
Danielle N. Edwards ◽  
Raymond Wong ◽  
Ivana Rajkovic ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Side Effects ◽  
Carotid Artery ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Interleukin 1 ◽  
Artery Occlusion ◽  
Cerebral Artery Occlusion

Abstract Background Stroke remains a leading cause of death and disability worldwide despite recent treatment breakthroughs. A primary event in stroke pathogenesis is the development of a potent and deleterious local and peripheral inflammatory response regulated by the pro-inflammatory cytokine interleukin-1 (IL-1). While the role of IL-1β (main released isoform) has been well studied in stroke, the role of the IL-1α isoform remains largely unknown. With increasing utilization of intravenous tissue plasminogen activator (t-PA) or thrombectomy to pharmacologically or mechanically remove ischemic stroke causing blood clots, respectively, there is interest in pairing successful cerebrovascular recanalization with neurotherapeutic pharmacological interventions (Fraser et al., J Cereb Blood Flow Metab 37:3531–3543, 2017; Hill et al., Lancet Neurol 11:942–950, 2012; Amaro et al., Stroke 47:2874–2876, 2016). Methods Transient stroke was induced in mice via one of two methods. One group of mice were subjected to tandem ipsilateral common carotid artery and middle cerebral artery occlusion, while another group underwent the filament-based middle cerebral artery occlusion. We have recently developed an animal model of intra-arterial (IA) drug administration after recanalization (Maniskas et al., J Neurosci Met 240:22–27, 2015). Sub groups of the mice were treated with either saline or Il-1α, wherein the drug was administered either acutely (immediately after surgery) or subacutely (on the third day after stroke). This was followed by behavioral and histological analyses. Results We now show in the above-mentioned mouse stroke models (transient tandem ipsilateral common carotid artery (CCA) and middle cerebral artery occlusion (MCA) occlusion, MCA suture occlusion) that IL-1α is neuroprotective when acutely given either intravenously (IV) or IA at low sub-pathologic doses. Furthermore, while IV administration induces transient hemodynamic side effects without affecting systemic markers of inflammation, IA delivery further improves overall outcomes while eliminating these side effects. Additionally, we show that delayed/subacute IV IL-1α administration ameliorates functional deficit and promotes neurorepair. Conclusions Taken together, our present study suggests for the first time that IL-1α could, unexpectedly, be an effective ischemic stroke therapy with a broad therapeutic window.

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