cPKCγ-Modulated Autophagy in Neurons Alleviates Ischemic Injury in Brain of Mice with Ischemic Stroke Through Akt-mTOR Pathway

2016 ◽  
Vol 7 (6) ◽  
pp. 497-511 ◽  
Author(s):  
Haiping Wei ◽  
Yun Li ◽  
Song Han ◽  
Shuiqiao Liu ◽  
Nan Zhang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Ischemic Injury ◽  
Mtor Pathway

scholarly journals Urokinase-type plasminogen activator (uPA) protects the tripartite synapse in the ischemic brain via ezrin-mediated formation of peripheral astrocytic processes

2018 ◽  
Vol 39 (11) ◽  
pp. 2157-2171 ◽  
Author(s):  
Ariel Diaz ◽  
Paola Merino ◽  
Luis G Manrique ◽  
Lihong Cheng ◽  
Manuel Yepes
Keyword(s):  
Ischemic Stroke ◽  
Plasminogen Activator ◽  
Harmful Effect ◽  
Ischemic Injury ◽  
Adult Brain ◽  
Subsequent Formation ◽  
Ischemic Brain ◽  
Tripartite Synapse ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator

Cerebral ischemia has a harmful effect on the synapse associated with neurological impairment. The “tripartite synapse” is assembled by the pre- and postsynaptic terminals, embraced by astrocytic elongations known as peripheral astrocytic processes (PAPs). Ischemic stroke induces the detachment of PAPs from the synapse, leading to synaptic dysfunction and neuronal death. Ezrin is a membrane-associated protein, required for the formation of PAPs, that links the cell surface to the actin cytoskeleton. Urokinase-type plasminogen activator (uPA) is a serine proteinase that upon binding to its receptor (uPAR) promotes neurite growth during development. In the adult brain, neurons release uPA and astrocytes recruit uPAR to the plasma membrane during the recovery phase from an ischemic stroke, and uPA/uPAR binding promotes functional improvement following an ischemic injury. We found that uPA induces the synthesis of ezrin in astrocytes, with the subsequent formation of PAPs that enter in direct contact with the synapse. Furthermore, either the release of neuronal uPA or intravenous treatment with recombinant uPA (ruPA) induces the formation of PAPs in the ischemic brain, and the interaction of these PAPs with the pre- and postsynaptic terminals protects the integrity of the “tripartite synapse” from the harmful effects of the ischemic injury.

scholarly journals Glutathione Suppresses Cerebral Infarct Volume and Cell Death after Ischemic Injury: Involvement of FOXO3 Inactivation and Bcl2 Expression

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Juhyun Song ◽  
Joohyun Park ◽  
Yumi Oh ◽  
Jong Eun Lee
Keyword(s):  
Cell Death ◽  
Ischemic Stroke ◽  
Cerebral Infarction ◽  
Infarct Size ◽  
Cell Survival ◽  
Ischemia Reperfusion ◽  
Ischemic Injury ◽  
Cerebral Infarct ◽  
Ros Scavenging ◽  
The Brain

Ischemic stroke interrupts the flow of blood to the brain and subsequently results in cerebral infarction and neuronal cell death, leading to severe pathophysiology. Glutathione (GSH) is an antioxidant with cellular protective functions, including reactive oxygen species (ROS) scavenging in the brain. In addition, GSH is involved in various cellular survival pathways in response to oxidative stress. In the present study, we examined whether GSH reduces cerebral infarct size after middle cerebral artery occlusionin vivoand the signaling mechanisms involved in the promotion of cell survival after GSH treatment under ischemia/reperfusion conditionsin vitro. To determine whether GSH reduces the extent of cerebral infarction, cell death after ischemia, and reperfusion injury, we measured infarct size in ischemic brain tissue and the expression of claudin-5 associated with brain infarct formation. We also examined activation of the PI3K/Akt pathway, inactivation of FOXO3, and expression of Bcl2 to assess the role of GSH in promoting cell survival in response to ischemic injury. Based on our results, we suggest that GSH might improve the pathogenesis of ischemic stroke by attenuating cerebral infarction and cell death.

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.

Localized Brain Tissue Cooling for Use During Intracranial Thrombectomy

2012 ◽  
Author(s):  
Thomas L. Merrill ◽  
Denise R. Merrill ◽  
Jennifer E. Akers
Keyword(s):  
Ischemic Stroke ◽  
Reperfusion Injury ◽  
Brain Tissue ◽  
Ischemic Injury ◽  
Blood Perfusion ◽  
Neuroprotective Agents ◽  
Tissue Necrosis ◽  
Stroke Treatment ◽  
Neurological Outcomes

The primary goal of current ischemic stroke treatment is quickly restoring blood perfusion. Recanalization is linked to improved neurological outcomes [1]. Resulting tissue necrosis, however, following a stroke has two causes: 1) ischemic injury and 2) reperfusion injury. Therefore, development of neuroprotective agents specifically beneficial against reperfusion injury are required.

scholarly journals Borneol for Regulating the Permeability of the Blood-Brain Barrier in Experimental Ischemic Stroke: Preclinical Evidence and Possible Mechanism

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Zi-xian Chen ◽  
Qing-qing Xu ◽  
Chun-shuo Shan ◽  
Yi-hua Shi ◽  
Yong Wang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Blood Brain Barrier ◽  
Ischemic Injury ◽  
Brain Barrier ◽  
Brain Diseases ◽  
Glycoprotein P ◽  
Blood Brain ◽  
Cerebral Ischemic Injury ◽  
Bbb Permeability ◽  
Cerebral Ischemic

Borneol, a natural product in the Asteraceae family, is widely used as an upper ushering drug for various brain diseases in many Chinese herbal formulae. The blood-brain barrier (BBB) plays an essential role in maintaining a stable homeostatic environment, while BBB destruction and the increasing BBB permeability are common pathological processes in many serious central nervous system (CNS) diseases, which is especially an essential pathological basis of cerebral ischemic injury. Here, we aimed to conduct a systematic review to assess preclinical evidence of borneol for experimental ischemic stroke as well as investigate in the possible neuroprotective mechanisms, which mainly focused on regulating the permeability of BBB. Seven databases were searched from their inception to July 2018. The studies of borneol for ischemic stroke in animal models were included. RevMan 5.3 was applied for data analysis. Fifteen studies investigated the effects of borneol in experimental ischemic stroke involving 308 animals were ultimately identified. The present study showed that the administration of borneol exerted a significant decrease of BBB permeability during cerebral ischemic injury according to brain Evans blue content and brain water content compared with controls (P<0.01). In addition, borneol could improve neurological function scores (NFS) and cerebral infarction area. Thus, borneol may be a promising neuroprotective agent for cerebral ischemic injury, largely through alleviating the BBB disruption, reducing oxidative reactions, inhibiting the occurrence of inflammation, inhibiting apoptosis, and improving the activity of lactate dehydrogenase (LDH) as well as P-glycoprotein (P-GP) and NO signaling pathway.

scholarly journals Influence of miR-155 on Cell Apoptosis in Rats with Ischemic Stroke: Role of the Ras Homolog Enriched in Brain (Rheb)/mTOR Pathway

2016 ◽  
Vol 22 ◽  
pp. 5141-5153 ◽  
Author(s):  
Guoping Xing ◽  
Zengxiang Luo ◽  
Chi Zhong ◽  
Xudong Pan ◽  
Xiaowei Xu
Keyword(s):  
Ischemic Stroke ◽  
Cell Apoptosis ◽  
Mtor Pathway

scholarly journals Temporal and Spatial Expression Characteristics of MiR-155 and Rheb/mTOR Signaling Pathway in Ischemia–Reperfusion Injury of Rats

2021 ◽  
Author(s):  
Yu-E Yan ◽  
Xu-Rong Zhu ◽  
Fang He ◽  
Jing Xiong ◽  
Ye Tian ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Ischemia Reperfusion ◽  
Statistical Significance ◽  
Mrna Level ◽  
Intervention Strategy ◽  
Mtor Pathway ◽  
Mrna Levels ◽  
Significant Difference ◽  
Ischemic Core ◽  
Expression Characteristics

Abstract Backgrouds: Stroke is the second most prevalent cause of death and the first cause of longterm disability worldwide. Inhibition of miR-155 was found playing a protective role in ischemic stroke, one possible mechanism was regulating Ras-homolog enriched in brain (Rheb)/mammalian target of rapamycin (mTOR) pathway. For possible specific intervention strategy, further exploring the expression characteristics of miR-155 and mRNAs of the Rheb/mTOR pathway in ischemic stroke is neccesary. Results: Our results demonstrated that the infarction volume decreased with the prolongation of the reperfusion in the MCAO/R model rats (P < 0.05). Meanwhile, the miR155 expression obviously increased in both the ischemic core and the ischemic penumbra (IP) area of the model rats, but this trend weakened as the reperfusion time increased. Besides, the expression of mRNAs of Rheb, mTOR, S6kb1, and 4Ebp1 seemed to increase in both the ischemic core and the IP area of the model rats.Interestingly, the mRNA level of S6kb1 obviously increased of all model groups in both the ischemic core and the IP area (P < 0.05),while the mRNA levels of Rheb, mTOR, and 4Ebp1 increased in the first 24 h and rapidly decreased after 48 h and as a result, a statistically significant difference was found only in the 48-h group (P < 0.05). Conclusion: Along with the shrinked infarct volume, the levels of miR-155 decreased and the S6kb1 mRNA level increased as the leghtening of re-perfusion, as to the mRNA levels of Rheb, mTOR, and 4Ebp1,statistical significance was found only in the 48-h group. Unexpectedly, there was no difference between the ischemic core and the IP area for all the above molecules.Indicating that intervention measures targeting to miR155 should be taken systemicly as early as possible after stroke onset,especially within the early 48 hours.

scholarly journals The TDP43 CFTS Affect Brain Endothelial Cell Functions by Regulating YAP and Tight Junction Proteins in Cerebral Ischemic Injury.

2021 ◽  
Author(s):  
Xiaotian Xu ◽  
Changwen Zhang ◽  
Jianxiong Jiang ◽  
Mei Xin ◽  
Jiukuan Hao
Keyword(s):  
Endothelial Cells ◽  
Ischemic Stroke ◽  
Protein Expression ◽  
Tight Junction ◽  
Signaling Pathway ◽  
Ischemic Injury ◽  
Hippo Signaling ◽  
Brain Endothelial Cells ◽  
Hippo Signaling Pathway ◽  
Cerebral Ischemic

Abstract Background: As important components of the blood-brain barrier (BBB), brain endothelial cells (ECs) interact with pericytes, astrocytes, neurons, microglia and extracellular matrix in the neurovascular unit to maintain central nerve system (CNS) homeostasis and regulate neurological functions. Pathological changes in brain endothelium plays an important role in progression of ischemic stroke. The compromised BBB under ischemic stroke condition causes neuronal damage. However, the pathophysiological mechanisms of BBB in normal and under ischemic stroke condition has not been fully elucidated.Methods: C57bl/6 mice were subjected to 1-hour transient middle cerebral occlusion (tMCAO) model, and collected the brain samples after reperfusion for 24hours, 72hours and 1week. Lentivirus (YAP/TAZ shRNA), adenovirus (YAPS112A), TDP43 siRNA, TDP43-CTFS35 overexpression plasmid, Oxygen-glucose deprivation (OGD), and lipopolysaccharides (LPS) were applied to brain endothelial cells in vitro experiments. Brain endothelial cells (ECs) functions were tested by cell proliferation, migration and cell viability. Hippo signaling pathway was examined by immunofluorescence and western blotting.Results: The present study demonstrates that TDP43 is an essential gene to regulate brain ECs normal function, and knockdown of TDP43 reduces tight junction protein expression and inhibits brain ECs migration. Furthermore, ischemic injury and inflammation induce cytoplasmic TDP43-CTFS35 aggregation brain ECs, which weaken TDP43 full-length’s function leading to impairing tight junction (TJ) protein expression and cell migration. The expression of cytoplasmic TDP43-CTFS35 in brain ECs increased at 24 hours and 72 hours after MCAO, but disappeared at 1 week after MCAO. The expressions of TJ proteins, ZO-1 and claudin-5, and expression of P-YAP are associated with the dynamic changes of TDP43-CTFS35 expression in brain ECs after MCAO. The underlying mechanism of TDP43-CTFS35’s effects on brain ECs is that TDP43-CTFS35 turns off the Hippo signaling pathway by inhibition of PMST1/2 phosphorylation leading to de-phosphorylate YAP, and subsequently causes brain ECs functional changes.Conclusions: The present study provides new insight knowledge regarding the mechanisms of brain vascular ECs regulation and pathological change in the BBB after cerebral ischemic injury.

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