Ras-like Gem GTPase induced by Npas4 promotes activity-dependent neuronal tolerance for ischemic stroke

Ischemic stroke, which results in loss of neurological function, initiates a complex cascade of pathological events in the brain, largely driven by excitotoxic Ca2+ influx in neurons. This leads to cortical spreading depolarization, which induces expression of genes involved in both neuronal death and survival; yet, the functions of these genes remain poorly understood. Here, we profiled gene expression changes that are common to ischemia (modeled by middle cerebral artery occlusion [MCAO]) and to experience-dependent activation (modeled by exposure to an enriched environment [EE]), which also induces Ca2+ transients that trigger transcriptional programs. We found that the activity-dependent transcription factor Npas4 was up-regulated under MCAO and EE conditions and that transient activation of cortical neurons in the healthy brain by the EE decreased cell death after stroke. Furthermore, both MCAO in vivo and oxygen-glucose deprivation in vitro revealed that Npas4 is necessary and sufficient for neuroprotection. We also found that this protection involves the inhibition of L-type voltage-gated Ca2+ channels (VGCCs). Next, our systematic search for Npas4-downstream genes identified Gem, which encodes a Ras-related small GTPase that mediates neuroprotective effects of Npas4. Gem suppresses the membrane localization of L-type VGCCs to inhibit excess Ca2+ influx, thereby protecting neurons from excitotoxic death after in vitro and in vivo ischemia. Collectively, our findings indicate that Gem expression via Npas4 is necessary and sufficient to promote neuroprotection in the injured brain. Importantly, Gem is also induced in human cerebral organoids cultured under an ischemic condition, revealing Gem as a new target for drug discovery.

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Neuroprotective Effects of microRNA-140-5p on Ischemic Stroke in Mice via its Regulation on the TLR4/NF-κB Axis

10.21203/rs.3.rs-45332/v1 ◽

2020 ◽

Author(s):

Song Wenjun ◽

Tiancheng Wang ◽

Bei Shi ◽

Zhijun Wu ◽

Wenjie Wang ◽

...

Keyword(s):

Ischemic Stroke ◽

Glucose Deprivation ◽

Artery Occlusion ◽

Luciferase Reporter ◽

Tunel Staining ◽

Related Factors ◽

Neuroprotective Effects ◽

High Level

Abstract Background and aim: Ischemic stroke is one of the main causes of death worldwide and permanent global disability. On the basis of existing literature data, we carried out studies in an effort to explore how miR-140-5p affects ischemic stroke and whether the mechanism relates to toll-like receptor-4 (TLR4) and nuclear factor-kappa B (NF-κB).Methods: Middle cerebral artery occlusion (MCAO) was employed to establish a mouse model of ischemic stroke in vivo, while primary neurons were exposed to oxygen-glucose deprivation (OGD) to set up an ischemic stroke model in vitro. RT-qPCR was performed to detect the miR-140-5p expression and Western blot was employed to detect the expression TLR4, NF-κB, and apoptosis-related factors. Then, based gain-function of experiments using miR-140-5p mimic and TLR4 overexpression plasmid, neurological function score, TTC staining, TUNEL staining, as well as flow cytometry were carried out to evaluate the effects of miR-140-5p and TLR4 on MCAO mice and OGD neurons. Meanwhile, dual-luciferase reporter assay was used to validate the relationship between miR-140-5p and TLR4.Results: miR-140-5p expressed at a low level and TLR4 at a high level in ischemic stroke. It was verified that miR-140-5p targeted TLR4 and downregulated its expression. miR-140-5p overexpression was observed to inhibit the apoptosis of neurons under OGD exposure and restrain the progression of ischemic stroke, while TLR4 overexpression promoted the apoptosis and disease progression. Besides, miR-140-5p overexpression led to a decrease in NF-κB protein level, which was increased by TLR4 overexpression. Conclusion: In conclusion, from our data we conclude that miR-140-5p overexpression may be instrumental for the therapeutic targeting of ischemic stroke by alleviating neuron injury with the involvement of TLR4/NF-κB axis.

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Modulator of apoptosis-1 is a potential therapeutic target in acute ischemic injury

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x18794839 ◽

2018 ◽

Vol 39 (12) ◽

pp. 2406-2418 ◽

Cited By ~ 3

Author(s):

Su Jing Chan ◽

Hui Zhao ◽

Kazuhide Hayakawa ◽

Chou Chai ◽

Chong Teik Tan ◽

...

Keyword(s):

Cortical Neurons ◽

Infarct Volume ◽

Neuronal Loss ◽

Ischemic Injury ◽

Glucose Deprivation ◽

Artery Occlusion ◽

In Vivo Models ◽

The Brain

Modulator of apoptosis 1 (MOAP-1) is a Bax-associating protein highly enriched in the brain. In this study, we examined the role of MOAP-1 in promoting ischemic injuries following a stroke by investigating the consequences of MOAP-1 overexpression or deficiency in in vitro and in vivo models of ischemic stroke. MOAP-1 overexpressing SH-SY5Y cells showed significantly lower cell viability following oxygen and glucose deprivation (OGD) treatment when compared to control cells. Consistently, MOAP-1−/− primary cortical neurons were observed to be more resistant against OGD treatment than the MOAP-1+/+ primary neurons. In the mouse transient middle cerebral artery occlusion (tMCAO) model, ischemia triggered MOAP-1/Bax association, suggested activation of the MOAP-1-dependent apoptotic cascade. MOAP-1−/− mice were found to exhibit reduced neuronal loss and smaller infarct volume 24 h after tMCAO when compared to MOAP-1+/+ mice. Correspondingly, MOAP-1−/− mice also showed better integrity of neurological functions as demonstrated by their performance in the rotarod test. Therefore, both in vitro and in vivo data presented strongly support the conclusion that MOAP-1 is an important apoptotic modulator in ischemic injury. These results may suggest that a reduction of MOAP-1 function in the brain could be a potential therapeutic approach in the treatment of acute stroke.

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A Probable Dual Mode of Action for Both L- and D-Lactate Neuroprotection in Cerebral Ischemia

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2015.115 ◽

2015 ◽

Vol 35 (10) ◽

pp. 1561-1569 ◽

Cited By ~ 37

Author(s):

Ximena Castillo ◽

Katia Rosafio ◽

Matthias T Wyss ◽

Konstantin Drandarov ◽

Alfred Buck ◽

...

Keyword(s):

Alternative Energy ◽

Receptor Agonist ◽

Glucose Deprivation ◽

Artery Occlusion ◽

Receptor Expression ◽

Neuroprotective Effects ◽

Energy Substrate ◽

Deprivation Model

Lactate has been shown to offer neuroprotection in several pathologic conditions. This beneficial effect has been attributed to its use as an alternative energy substrate. However, recent description of the expression of the HCA1 receptor for lactate in the central nervous system calls for reassessment of the mechanism by which lactate exerts its neuroprotective effects. Here, we show that HCA1 receptor expression is enhanced 24 hours after reperfusion in an middle cerebral artery occlusion stroke model, in the ischemic cortex. Interestingly, intravenous injection of L-lactate at reperfusion led to further enhancement of HCA1 receptor expression in the cortex and striatum. Using an in vitro oxygen-glucose deprivation model, we show that the HCA1 receptor agonist 3,5-dihydroxybenzoic acid reduces cell death. We also observed that D-lactate, a reputedly non-metabolizable substrate but partial HCA1 receptor agonist, also provided neuroprotection in both in vitro and in vivo ischemia models. Quite unexpectedly, we show D-lactate to be partly extracted and oxidized by the rodent brain. Finally, pyruvate offered neuroprotection in vitro whereas acetate was ineffective. Our data suggest that L- and D-lactate offer neuroprotection in ischemia most likely by acting as both an HCA1 receptor agonist for non-astrocytic (most likely neuronal) cells as well as an energy substrate.

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Restoration of Polyamine Metabolic Patterns inIn VivoandIn VitroModel of Ischemic Stroke following Human Mesenchymal Stem Cell Treatment

Stem Cells International ◽

10.1155/2016/4612531 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 10

Author(s):

Tae Hwan Shin ◽

Geetika Phukan ◽

Jeom Soon Shim ◽

Duc-Toan Nguyen ◽

Yongman Kim ◽

...

Keyword(s):

Ischemic Stroke ◽

Cell Model ◽

Glucose Deprivation ◽

Human Mesenchymal Stem Cell ◽

Artery Occlusion ◽

Control Group ◽

Stem Cell Treatment ◽

Cerebral Artery Occlusion

We investigated changes in PA levels by the treatment of human bone-marrow-derived mesenchymal stem cells (hBM-MSCs) in ischemic stroke in rat brain model and in cultured neuronal SH-SY5Y cells exposed to oxygen-glucose deprivation (OGD). In ischemic rat model, transient middle cerebral artery occlusion (MCAo) was performed for 2 h, followed by intravenous transplantation of hBM-MSCs or phosphate-buffered saline (PBS) the day following MCAo. Metabolic profiling analysis of PAs was examined in brains from three groups: control rats, PBS-treated MCAo rats (MCAo), and hBM-MSCs-treated MCAo rats (MCAo + hBM-MSCs). In ischemic cell model, SH-SY5Y cells were exposed to OGD for 24 h, treated with hBM-MSCs (OGD + hBM-MSCs) prior to continued aerobic incubation, and then samples were collected after coculture for 72 h. In thein vivoMCAo ischemic model, levels of some PAs in brain samples of the MCAo and MCAo + hBM-MSCs groups were significantly different from those of the control group. In particular, putrescine, cadaverine, and spermidine in brain tissues of the MCAo + hBM-MSCs group were significantly reduced in comparison to those in the MCAo group. In thein vitroOGD system,N1-acetylspermidine, spermidine,N1-acetylspermine, and spermine in cells of the OGD + hBM-MSCs group were significantly reduced compared to those of OGD group.

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GATA3 (GATA-Binding Protein 3)/KMT2A (Lysine-Methyltransferase-2A) Complex by Increasing H3K4-3me (Trimethylated Lysine-4 of Histone-3) Upregulates NCX3 (Na + -Ca 2+ Exchanger 3) Transcription and Contributes to Ischemic Preconditioning Neuroprotection

Stroke ◽

10.1161/strokeaha.121.034637 ◽

2021 ◽

Vol 52 (11) ◽

pp. 3680-3691

Author(s):

Natascia Guida ◽

Luigi Mascolo ◽

Angelo Serani ◽

Ornella Cuomo ◽

Serenella Anzilotti ◽

...

Keyword(s):

Ischemic Preconditioning ◽

Cortical Neurons ◽

Promoter Region ◽

Glucose Deprivation ◽

Artery Occlusion ◽

Histone 3 ◽

Lysine Methyltransferase ◽

Cerebral Artery Occlusion

Background and Purpose: NCX3 (Na + -Ca 2+ exchanger 3) plays a relevant role in stroke; indeed its pharmacological blockade or its genetic ablation exacerbates brain ischemic damage, whereas its upregulation takes part in the neuroprotection elicited by ischemic preconditioning. To identify an effective strategy to induce an overexpression of NCX3, we examined transcription factors and epigenetic mechanisms potentially involved in NCX3 gene regulation. Methods: Brain ischemia and ischemic preconditioning were induced in vitro by exposure of cortical neurons to oxygen and glucose deprivation plus reoxygenation (OGD/Reoxy) and in vivo by transient middle cerebral artery occlusion. Western blot and quantitative real-time polymerase chain reaction were used to evaluate transcripts and proteins of GATA3 (GATA-binding protein 3), KMT2A (lysine-methyltransferase-2A), and NCX3. GATA3 and KMT2A binding on NCX3 gene was evaluated by chromatin immunoprecipitation and Rechromatin immunoprecipitation experiments. Results: Among the putative transcription factors sharing a consensus sequence on the ncx3 brain promoter region, GATA3 was the only able to up-regulate ncx3. Interestingly, GATA3 physically interacted with KMT2A, and their overexpression or knocking-down increased or downregulated NCX3 mRNA and protein, respectively. Notably, site-direct mutagenesis of GATA site on ncx3 brain promoter region counteracted GATA3 and KMT2A binding on NCX3 gene. More importantly, we found that in the perischemic cortical regions of preconditioned rats GATA3 recruited KMT2A and the complex H3K4-3me (trimethylated lysine-4 of histone-3) on ncx3 brain promoter region, thus reducing transient middle cerebral artery occlusion–induced damage. Consistently, in vivo silencing of either GATA3 or KMT2A prevented NCX3 upregulation and consequently the neuroprotective effect of preconditioning stimulus. The involvement of GATA3/KMT2A complex in neuroprotection elicited by ischemic preconditioning was further confirmed by in vitro experiments in which the knocking-down of GATA3 and KMT2A reverted the neuroprotection induced by NCX3 overexpression in cortical neurons exposed to anoxic preconditioning followed by oxygen and glucose deprivation plus reoxygenation. Conclusions: Collectively, our results revealed that GATA3/KMT2A complex epigenetically activates NCX3 gene transcription during ischemic preconditioning.

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MLIF Modulates Microglia Polarization in Ischemic Stroke by Targeting eEF1A1

Frontiers in Pharmacology ◽

10.3389/fphar.2021.725268 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yulan Liu ◽

Shanshan Deng ◽

Zhibing Song ◽

Qian Zhang ◽

Yuchen Guo ◽

...

Keyword(s):

Ischemic Stroke ◽

Macrophage Polarization ◽

Elongation Factor ◽

Glucose Deprivation ◽

Artery Occlusion ◽

Human Neuroblastoma ◽

Associated Proteins ◽

Bv2 Microglia

Monocyte locomotion inhibitory factor (MLIF) is a heat-stable pentapeptide from Entamoeba histolytica. Our previous study found that MLIF protects against ischemic stroke in rats and mice and exerts a neuroprotection effect in human neuroblastoma SH-SY5Y cells. Microglia/macrophage polarization has been proven to be vital in the pathology of ischemic stroke. Nevertheless, whether MLIF is able to modulate microglia/macrophage polarization remains unclear. We performed middle cerebral artery occlusion (MCAO) on C57BL/6J male mice and induced cultured BV2 microglia by oxygen-glucose deprivation (OGD), respectively. Immunfluorescence was utilized to detect the M1/2 markers, such as CD206 and CD16/32. qPCR and ELISA were used to detect the signature gene change of M1/2. The MAPK and NF-κB pathway associated proteins were measured by Western blot. To identify the protein target of MLIF, a pull-down assay was performed. We found that MLIF promoted microglia transferring from a “sick” M1 phenotype to a “healthy” M2 phenotype in vivo or in vitro. Furthermore, we proved that eukaryotic elongation factor 1A1 (eEF1A1) was involved in the modulation of microglia/macrophage polarization. Knocking down eEF1A1 by siRNA exhibited the M1 promotion effect and M2 inhibition effect. Taken together, our results demonstrated MLIF modulated microglia/macrophage polarization by targeting eEF1A1 in ischemic stroke.

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Cerebroprotective effect of xantohumol sensu experimental stroke model: study design and preliminary results

Saratov Medical Journal ◽

10.15275/sarmj.2021.0103 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Aigul Saitgareyeva ◽

Leyla Akhmadeyeva

Keyword(s):

Ischemic Stroke ◽

Cortical Neurons ◽

Glucose Deprivation ◽

Experimental Stroke ◽

Control Group ◽

Stroke Model ◽

Sprague Dawley ◽

Preliminary Results

The objective of our study was to evaluate the cerebroprotective effect of xanthohumol (ХN) on experimental models of acute ischemic stroke in vivo and in vitro. Materials and methods. We used middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation (OGD) as in vivo and in vitro models. Our study subjects were Sprague-Dawley rats, which were randomly assigned to three groups: the control group and two MCAO groups with and without XN. The primary culture of cortical neurons was obtained from newborn rats. We employed the Bederson test and the corner test to evaluate neurological disorders. Results. The preliminary results indicated a possible cerebroprotective effect of XN in an ischemic stroke model. Conclusion. Preventive administration of XN before cerebral ischemia in an experiment can effectively reduce the volume of cerebral infarction and improve neurologic deficit 24 hours after MCAO.

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LINGO-1 shRNA protects the brain against ischemia/reperfusion injury by inhibiting the activation of NF-κB and JAK2/STAT3

Human Cell ◽

10.1007/s13577-021-00527-x ◽

2021 ◽

Author(s):

Jiaying Zhu ◽

Zhu Zhu ◽

Yipin Ren ◽

Yukang Dong ◽

Yaqi Li ◽

...

Keyword(s):

Cerebral Ischemia ◽

Nuclear Translocation ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Glucose Deprivation ◽

Artery Occlusion ◽

Mice Model ◽

Down Regulation

AbstractLINGO-1 may be involved in the pathogenesis of cerebral ischemia. However, its biological function and underlying molecular mechanism in cerebral ischemia remain to be further defined. In our study, middle cerebral artery occlusion/reperfusion (MACO/R) mice model and HT22 cell oxygen–glucose deprivation/reperfusion (OGD/R) were established to simulate the pathological process of cerebral ischemia in vivo and in vitro and to detect the relevant mechanism. We found that LINGO-1 mRNA and protein were upregulated in mice and cell models. Down-regulation LINGO-1 improved the neurological symptoms and reduced pathological changes and the infarct size of the mice after MACO/R. In addition, LINGO-1 interference alleviated apoptosis and promoted cell proliferation in HT22 of OGD/R. Moreover, down-regulation of LINGO-1 proved to inhibit nuclear translocation of p-NF-κB and reduce the expression level of p-JAK2 and p-STAT3. In conclusion, our data suggest that shLINGO-1 attenuated ischemic injury by negatively regulating NF-KB and JAK2/STAT3 pathways, highlighting a novel therapeutic target for ischemic stroke.

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

10.21203/rs.3.rs-297082/v1 ◽

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.

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Privileged Quinolylnitrones for the Combined Therapy of Ischemic Stroke and Alzheimer’s Disease

Pharmaceuticals ◽

10.3390/ph14090861 ◽

2021 ◽

Vol 14 (9) ◽

pp. 861

Author(s):

José M. Alonso ◽

Alejandro Escobar-Peso ◽

Alejandra Palomino-Antolín ◽

Daniel Diez-Iriepa ◽

Mourad Chioua ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Ischemic Stroke ◽

Cortical Neurons ◽

Combined Therapy ◽

Glucose Deprivation ◽

Dual Therapy ◽

Amyloid Peptide ◽

Neuroprotective Effects ◽

Number Of Patients

Cerebrovascular diseases such as ischemic stroke are known to exacerbate dementia caused by neurodegenerative pathologies such as Alzheimer’s disease (AD). Besides, the increasing number of patients surviving stroke makes it necessary to treat the co-occurrence of these two diseases with a single and combined therapy. For the development of new dual therapeutic agents, eight hybrid quinolylnitrones have been designed and synthesized by the juxtaposition of selected pharmacophores from our most advanced lead-compounds for ischemic stroke and AD treatment. Biological analyses looking for efficient neuroprotective effects in suitable phenotypic assays led us to identify MC903 as a new small quinolylnitrone for the potential dual therapy of stroke and AD, showing strong neuroprotection on (i) primary cortical neurons under oxygen–glucose deprivation/normoglycemic reoxygenation as an experimental ischemia model; (ii), neuronal line cells treated with rotenone/oligomycin A, okadaic acid or β-amyloid peptide Aβ25–35, modeling toxic insults found among the effects of AD.

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