Expression and Distribution Pattern of Pnn in Ischemic Cerebral Cortex and Cultured Neural Cells Exposed to Oxygen-Glucose Deprivation

Pinin (Pnn), a multifunctional protein, participates in embryonic development as well as in cellular apoptosis, proliferation, and migration through regulating mRNA alternative splicing and gene transcription. Previous studies have shown that Pnn plays important roles in neural system development and the expression level of Pnn in astrocytes is altered by ischemic stress and associated with cellular apoptosis. In the present study, we further utilized primary cultured rat neurons and astrocytes with oxygen-glucose deprivation (OGD) and a mouse model with middle cerebral artery occlusion (MCAO)-induced ischemic stroke to examine the effect of ischemic stress on Pnn expression and distribution in different types of neural cells. Under normoxia, Pnn is mainly localized in the nuclear speckle of primary cultured neurons. The expression level of Pnn was increased after the OGD treatment and then decreased in the reoxygenation period. Moreover, the cytoplasmic expression of Pnn was observed in neurons with OGD and reoxygenation (OGD/R). Unlike that in neurons, the Pnn expression in astrocytes was decreased after OGD treatment and then gradually increased during the reoxygenation period. Of interest, the nuclear–cytoplasmic translocation of Pnn was not observed in astrocytes with OGD/R. In the MCAO mouse model, the neuronal expression of Pnn in the peri-ischemic region was reduced by three days post induction of ischemic stroke. However, the Pnn expression in astrocytes was not altered. Moreover, the nuclear speckle distribution of Pnn in neurons was also diminished following ischemic stroke. In conclusion, the Pnn expression and distribution after OGD and during reoxygenation showed distinct manners in neurons and astrocytes, implying that Pnn may play different roles in different types of neural cells in the stress response to ischemic injury.

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GRP78 Promotes Neural Stem Cell Antiapoptosis and Survival in Response to Oxygen-Glucose Deprivation (OGD)/Reoxygenation through PI3K/Akt, ERK1/2, and NF-κB/p65 Pathways

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/3541807 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Qian Liu ◽

Yun Li ◽

Lin Zhou ◽

Yunzi Li ◽

Pengfei Xu ◽

...

Keyword(s):

Ischemic Stroke ◽

Ischemia Reperfusion ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Neural Cells ◽

Cellular Apoptosis ◽

Signalling Transduction ◽

The One ◽

New Evidence

When brain injury happens, endogenous neural stem cells (NSCs) located in the adult subventricular zone (SVZ) and subgranular zone (SGZ) are attacked by ischemia/reperfusion to undergo cellular apoptosis and death before being induced to migrate to the lesion point and differentiate into mature neural cells for damaged cell replacement. Although promoting antiapoptosis and NSC survival are critical to neuroregeneration, the mechanism has yet been elucidated clearly. Here in this study, we established an in vitro oxygen-glucose deprivation (OGD)/reoxygenation model on NSCs and detected glucose-regulated protein 78 (GRP78) involved in apoptosis, while in the absence of GRP78 by siRNA transfection, OGD/reoxygenation triggered PI3K/Akt, ERK1/2, and NF-κB/p65 activation, and induced NSC apoptosis was attenuated. Further investigation, respectively, with the inhibitor of PI3K/Akt or ERK1/2 demonstrated a blockage on GRP78 upregulation, while the inhibition of NF-κB rarely affected GRP78 induction by OGD/reoxygenation. The results indicated the bidirectional regulations of GRP78-PI3K/Akt and GRP78-ERK1/2 and the one-way signalling transduction through GRP78 to NF-κB/p65 on NSC survival from OGD/reoxygenation. In conclusion, we found that GRP78 mediated the signalling cross talk through PI3K/Akt, ERK1/2, and NF-κB/p65, which leads to antiapoptosis and NSC survival from ischemic stroke. Our finding gives a new evidence of GRP78 in NSCs as well as a new piece of signalling mechanism elucidation to NSC survival from ischemic stroke.

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Scoparone protects neuronal cells from oxygen glucose deprivation/reoxygenation injury

RSC Advances ◽

10.1039/c8ra09867k ◽

2019 ◽

Vol 9 (4) ◽

pp. 2302-2308 ◽

Cited By ~ 2

Author(s):

Chunfang Wu ◽

Ting Li ◽

Baihui Zhu ◽

Ruiming Zhu ◽

Youran Zhang ◽

...

Keyword(s):

Ischemic Stroke ◽

Causes Of Death ◽

Neuronal Cells ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

The World ◽

Reoxygenation Injury

Ischemic stroke is one of the leading causes of death and disability in the world.

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

Journal of Neurosurgery ◽

10.3171/2017.5.jns163165 ◽

2019 ◽

Vol 130 (3) ◽

pp. 977-988 ◽

Cited By ~ 10

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.

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

Stroke ◽

10.1161/strokeaha.118.023376 ◽

2019 ◽

Vol 50 (7) ◽

pp. 1850-1858 ◽

Cited By ~ 14

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.

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Effects of estradiol on ischemic factor-induced astrocyte swelling and AQP4 protein abundance

AJP Cell Physiology ◽

10.1152/ajpcell.00399.2010 ◽

2011 ◽

Vol 301 (1) ◽

pp. C204-C212 ◽

Cited By ~ 33

Author(s):

Jennifer M. Rutkowsky ◽

Breanna K. Wallace ◽

Phyllis M. Wise ◽

Martha E. O'Donnell

Keyword(s):

Ischemic Stroke ◽

Cell Volume ◽

Cerebral Edema ◽

Glucose Deprivation ◽

Aquaporin 4 ◽

Oxygen Glucose Deprivation ◽

Protein Abundance ◽

Astrocyte Swelling ◽

Aqp4 Protein ◽

Stimulation Of

In the early hours of ischemic stroke, cerebral edema forms as Na, Cl, and water are secreted across the blood-brain barrier (BBB) and astrocytes swell. We have shown previously that ischemic factors, including hypoxia, aglycemia, and arginine vasopressin (AVP), stimulate BBB Na-K-Cl cotransporter (NKCC) and Na/H exchanger (NHE) activities and that inhibiting NKCC and/or NHE by intravenous bumetanide and/or HOE-642 reduces edema and infarct in a rat model of ischemic stroke. Estradiol also reduces edema and infarct in this model and abolishes ischemic factor stimulation of BBB NKCC and NHE. There is evidence that NKCC and NHE also participate in ischemia-induced swelling of astrocytes. However, little is known about estradiol effects on astrocyte cell volume. In this study, we evaluated the effects of AVP (100 nM), hypoxia (7.5% O2), aglycemia, hypoxia (2%)/aglycemia [oxygen glucose deprivation (OGD)], and estradiol (1–100 nM) on astrocyte cell volume using 3- O-methyl-d-[3H]glucose equilibration methods. We found that AVP, hypoxia, aglycemia, and OGD (30 min to 5 h) each significantly increased astrocyte cell volume, and that estradiol (30–180 min) abolished swelling induced by AVP or hypoxia, but not by aglycemia or OGD. Bumetanide and/or HOE-642 also abolished swelling induced by AVP but not aglycemia. Abundance of aquaporin-4, known to participate in ischemia-induced astrocyte swelling, was significantly reduced following 7-day but not 2- or 3-h estradiol exposures. Our findings suggest that hypoxia, aglycemia, and AVP each contribute to ischemia-induced astrocyte swelling, and that the edema-attenuating effects of estradiol include reduction of hypoxia- and AVP-induced astrocyte swelling and also reduction of aquaporin-4 abundance.

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Relaxin Peptide Hormones Are Protective During the Early Stages of Ischemic Stroke in Male Rats

Endocrinology ◽

10.1210/en.2014-1676 ◽

2014 ◽

Vol 156 (2) ◽

pp. 638-646 ◽

Cited By ~ 9

Author(s):

Lindsay H. Bergeron ◽

Jordan M. Willcox ◽

Faisal J. Alibhai ◽

Barry J. Connell ◽

Tarek M. Saleh ◽

...

Keyword(s):

Nitric Oxide ◽

Ischemic Stroke ◽

Nitric Oxide Synthase ◽

Infarct Size ◽

Endothelial Nitric Oxide Synthase ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Protective Mechanisms ◽

Oxide Synthase ◽

Endothelial Nitric Oxide

The pregnancy hormone relaxin protects tissue from ischemic damage. The ability of relaxin-3, a relaxin paralog, to do so has not been explored. The cerebral expression levels of these peptides and their receptors make them logical targets for study in the ischemic brain. We assessed relaxin peptide-mediated protection, relative relaxin family peptide receptor (RXFP) involvement, and protective mechanisms. Sprague-Dawley rats receiving permanent (pMCAO) or transient middle cerebral artery occlusions (tMCAO) were treated with relaxin peptides, and brains were collected for infarct analysis. Activation of the endothelial nitric oxide synthase pathway was evaluated as a potential protective mechanism. Primary cortical rat astrocytes were exposed to oxygen glucose deprivation and treated with relaxin peptides, and viability was examined. Receptor involvement was explored using RXFP3 antagonist or agonist treatment and real-time PCR. Relaxin and relaxin-3 reduced infarct size after pMCAO. Both peptides activated endothelial nitric oxide synthase. Because relaxin-3 has not previously been associated with this pathway and displays promiscuous RXFP binding, we explored the receptor contribution. Expression of rxfp1 was greater than that of rxfp3 in rat brain, although peptide binding at either receptor resulted in similar overall protection after pMCAO. Only RXFP3 activation reduced infarct size after tMCAO. In astrocytes, rxfp3 gene expression was greater than that of rxfp1. Selective activation of RXFP3 maintained astrocyte viability after oxygen glucose deprivation. Relaxin peptides are protective during the early stages of ischemic stroke. Differential responses among treatments and models suggest that RXFP1 and RXFP3 initiate different protective mechanisms. This preliminary work is a pivotal first step in identifying the clinical implications of relaxin peptides in ischemic stroke.

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Exacerbation of oxygen–glucose deprivation-induced blood–brain barrier disruption: potential pathogenic role of interleukin-9 in ischemic stroke

Clinical Science ◽

10.1042/cs20170984 ◽

2017 ◽

Vol 131 (13) ◽

pp. 1499-1513 ◽

Cited By ~ 5

Author(s):

Sha Tan ◽

Yilong Shan ◽

Yuge Wang ◽

Yinyao Lin ◽

Siyuan Liao ◽

...

Keyword(s):

T Cells ◽

Ischemic Stroke ◽

Blood Brain Barrier ◽

Mononuclear Cells ◽

Biological Effects ◽

Glucose Deprivation ◽

Brain Barrier ◽

Oxygen Glucose Deprivation ◽

Expression Levels ◽

Blood Brain

Interleukin (IL)-9 exerts a variety of functions in autoimmune diseases. However, its role in ischemic brain injury remains unknown. The present study explored the biological effects of IL-9 in ischemic stroke (IS). We recruited 42 patients newly diagnosed with IS and 22 age- and sex-matched healthy controls. The expression levels of IL-9 and percentages of IL-9-producing T cells, including CD3+CD4+IL-9+ and CD3+CD8+IL-9+ cells, were determined in peripheral blood mononuclear cells (PBMCs) obtained from patients and control individuals. We also investigated the effects of IL-9 on the blood–brain barrier (BBB) following oxygen–glucose deprivation (OGD) and the potential downstream signaling pathways. We found that patients with IS had higher IL-9 expression levels and increased percentages of IL-9-producing T cells in their PBMCs. The percentages of CD3+CD4+IL-9+ and CD3+CD8+IL-9+ T cells were positively correlated with the severity of illness. In in vitro experiments using bEnd.3 cells, exogenously administered IL-9 exacerbated the loss of tight junction proteins (TJPs) in cells subjected to OGD plus reoxygenation (RO). This effect was mediated via activation of IL-9 receptors, which increased the level of endothelial nitric oxide synthase (eNOS), as well as through up-regulated phosphorylation of signal transducer and activator of transcription 1 and 3 and down-regulated phosphorylated protein kinase B/phosphorylated phosphatidylinositol 3-kinase signaling. These results indicate that IL-9 has a destructive effect on the BBB following OGD, at least in part by inducing eNOS production, and raise the possibility of targetting IL-9 for therapeutic intervention in IS.

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Methylglyoxal Scavengers Attenuate Angiogenesis Dysfunction Induced by Methylglyoxal and Oxygen-Glucose Deprivation

Oxidative Medicine and Cellular Longevity ◽

10.1155/2022/8854457 ◽

2022 ◽

Vol 2022 ◽

pp. 1-18

Author(s):

Wei Chen ◽

Wenhui Huang ◽

Yu Yang ◽

Keshen Li

Keyword(s):

Endothelial Cells ◽

Chorioallantoic Membrane ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Ros Generation ◽

Advanced Glycation ◽

Related Factors ◽

Cellular Apoptosis

Cerebral endothelial cells play an essential role in brain angiogenesis, and their function has been found to be impaired in diabetes. Methylglyoxal (MG) is a highly reactive dicarbonyl metabolite of glucose formed mainly during glycolysis, and its levels can be elevated in hyperglycemic conditions. MG is a potent precursor of AGEs (advanced glycation end-products). In this study, we investigated if MG can induce angiogenesis dysfunction and whether MG scavengers can ameliorate angiogenesis dysfunction induced by MG. Here, we used cultured human brain microvascular endothelial cells (HBMECs) treated with MG and oxygen-glucose deprivation (OGD) to mimic diabetic stroke in vitro. We also used the MG challenged chicken embryo chorioallantoic membrane (CAM) to study angiogenesis in vivo. Interestingly, administration of MG significantly impaired cell proliferation, cell migration, and tube formation and decreased protein expression of angiogenesis-related factors, which was rescued by three different MG scavengers, glyoxalase 1 (GLO1), aminoguanidine (AG), and N-acetyl cysteine (NAC). In cultured CAM, MG exposure significantly reduced angiogenesis and the angiogenesis-related dysfunction could be attenuated by pretreatment with AG or NAC. Treatment of cultured HBMECs with MG plus OGD increased cellular apoptosis significantly, which could be prevented by exposure to GLO1, AG, or NAC. We also noted that administration of MG increased cellular oxidative stress as measured by reactive oxygen species (ROS) generation, enhanced AGE accumulation, and receptor for advanced glycation end-product (RAGE) expression in the cultured HBMECs, which were partially reversed by GLO1, AG, or NAC. Taken together, our findings demonstrated that GLO1, AG, or NAC administration can ameliorate MG-induced angiogenesis dysfunction, and this can be mainly attributed to attenuated ROS production, reduced cellular apoptosis, and increased levels of angiogenic factors. Overall, this study suggested that GLO1, AG, or NAC may be promising candidate compounds for the treatment of angiogenesis dysfunction caused by hyperglycemia in diabetic ischemic stroke.

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Inhibition of N-myc Downstream–regulated Gene-2 Is Involved in an Astrocyte-specific Neuroprotection Induced by Sevoflurane Preconditioning

Anesthesiology ◽

10.1097/aln.0000000000000314 ◽

2014 ◽

Vol 121 (3) ◽

pp. 549-562 ◽

Cited By ~ 22

Author(s):

Xin Li ◽

Peng Luo ◽

Feng Wang ◽

Qianzi Yang ◽

Yan Li ◽

...

Keyword(s):

Nuclear Translocation ◽

Glucose Deprivation ◽

Terminal Deoxynucleotidyl Transferase ◽

Oxygen Glucose Deprivation ◽

Ndrg2 Expression ◽

Sevoflurane Preconditioning ◽

Cellular Apoptosis ◽

Cerebral Ischemic ◽

Interfering Rna

Abstract Background: Mechanism of sevoflurane preconditioning–induced cerebral ischemic tolerance is unclear. This study investigates the role of N-myc downstream–regulated gene-2 (NDRG2) in the neuroprotection of sevoflurane preconditioning in ischemic model both in vivo and in vitro. Methods: At 2 h after sevoflurane (2%) preconditioning for 1 h, rats were subjected to middle cerebral artery occlusion for 120 min. Neurobehavioral scores (n = 10), infarct volumes (n = 10), cellular apoptosis (n = 6), and NDRG2 expression (n = 6) were determined at 24 h after reperfusion. In vitro, cultural astrocytes were exposed to oxygen–glucose deprivation for 4 h. Cellular viability, cytotoxicity, apoptosis, and NDRG2 expression (n = 6) were evaluated in the presence or absence of NDRG2-specific small interfering RNA or NDRG2 overexpression plasmid. Results: Sevoflurane preconditioning decreased apoptosis (terminal deoxynucleotidyl transferase–mediated 2’-deoxyuridine 5’-triphosphate nick-end labeling–positive cells reduced to 31.2 ± 5.3% and cleaved Caspase-3 reduced to 1.42 ± 0.21 fold) and inhibited NDRG2 expression (1.28 ± 0.15 fold) and nuclear translocation (2.21 ± 0.29 fold) in ischemic penumbra. Similar effects were observed in cultural astrocytes exposed to oxygen–glucose deprivation. NDRG2 knockdown by small interfering RNA attenuated oxygen–glucose deprivation–induced injury (cell viability increased to 80.5 ± 4.1%; lactate dehydrogenase release reduced to 30.5 ± 4.0%) and cellular apoptosis (cleaved Caspase-3 reduced to 1.55 ± 0.21 fold; terminal deoxynucleotidyl transferase–mediated 2’-deoxyuridine 5’-triphosphate nick-end labeling–positive cells reduced to 18.2 ± 4.3%), whereas NDRG2 overexpression reversed the protective effects of sevoflurane preconditioning. All the data are presented as mean ± SD. Conclusion: Sevoflurane preconditioning inhibits NDRG2 up-regulation and nuclear translocation in astrocytes to induce cerebral ischemic tolerance via antiapoptosis, which represents one new mechanism of sevoflurane preconditioning and provides a novel target for neuroprotection.

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EphrinB2-EphB2 signaling for dendrite protection after neuronal ischemia in vivo and oxygen-glucose deprivation in vitro

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x20973119 ◽

2020 ◽

pp. 0271678X2097311

Author(s):

Zhanyang Yu ◽

Wenlu Li ◽

Jing Lan ◽

Kazuhide Hayakawa ◽

Xunming Ji ◽

...

Keyword(s):

Cerebral Ischemia ◽

Mouse Model ◽

Therapeutic Potential ◽

Focal Cerebral Ischemia ◽

Ischemic Injury ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Neuron Soma

In order to rescue neuronal function, neuroprotection should be required not only for the neuron soma but also the dendrites. Here, we propose the hypothesis that ephrin-B2-EphB2 signaling may be involved in dendritic degeneration after ischemic injury. A mouse model of focal cerebral ischemia with middle cerebral artery occlusion (MCAO) method was used for EphB2 signaling test in vivo. Primary cortical neuron culture and oxygen-glucose deprivation were used to assess EphB2 signaling in vitro. siRNA and soluble ephrin-B2 ectodomain were used to block ephrin-B2-Ephb2 signaling. In the mouse model of focal cerebral ischemia and in neurons subjected to oxygen-glucose deprivation, clustering of ephrin-B2 with its receptor EphB2 was detected. Phosphorylation of EphB2 suggested activation of this signaling pathway. RNA silencing of EphB2 prevented neuronal death and preserved dendritic length. To assess therapeutic potential, we compared the soluble EphB2 ectodomain with the NMDA antagonist MK801 in neurons after oxygen-glucose deprivation. Both agents equally reduced lactate dehydrogenase release as a general marker of neurotoxicity. However, only soluble EphB2 ectodomain protected the dendrites. These findings provide a proof of concept that ephrin-B2-EphB2 signaling may represent a novel therapeutic target to protect both the neuron soma as well as dendrites against ischemic injury.

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