scholarly journals Blockade of P2X7 Receptors or Pannexin-1 Channels Similarly Attenuates Postischemic Damage

2015 ◽  
Vol 35 (5) ◽  
pp. 843-850 ◽  
Author(s):  
Abraham Cisneros-Mejorado ◽  
Miroslav Gottlieb ◽  
Fabio Cavaliere ◽  
Tim Magnus ◽  
Friederich Koch-Nolte ◽  
...  
Keyword(s):  
Knockout Mice ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
Brain Slices ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Organotypic Cultures ◽  
P2x7 Receptors ◽  
Pannexin 1

The role of P2X7 receptors and pannexin-1 channels in ischemic damage remains controversial. Here, we analyzed their contribution to postanoxic depolarization after ischemia in cultured neurons and in brain slices. We observed that pharmacological blockade of P2X7 receptors or pannexin-1 channels delayed the onset of postanoxic currents and reduced their slope, and that simultaneous inhibition did not further enhance the effects of blocking either one. These results were confirmed in acute cortical slices from P2X7 and pannexin-1 knockout mice. Oxygen-glucose deprivation in cortical organotypic cultures caused neuronal death that was reduced with P2X7 and pannexin-1 blockers as well as in organotypic cultures derived from mice lacking P2X7 and pannexin 1. Subsequently, we used transient middle cerebral artery occlusion to monitor the neuroprotective effect of those drugs in vivo. We found that P2X7 and pannexin-1 antagonists, and their ablation in knockout mice, substantially attenuated the motor symptoms and reduced the infarct volume to ~50% of that in vehicle-treated or wild-type animals. These results show that P2X7 receptors and pannexin-1 channels are major mediators of postanoxic depolarization in neurons and of brain damage after ischemia, and that they operate in the same deleterious signaling cascade leading to neuronal and tissue demise.

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

2018 ◽  
Vol 39 (12) ◽  
pp. 2406-2418 ◽  
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.

scholarly journals Neuroprotective effect of Danshensu derivatives as anti-ischaemia agents on SH-SY5Y cells and rat brain

2013 ◽  
Vol 33 (4) ◽  
Author(s):  
Sunisa Seetapun ◽  
Jia Yaoling ◽  
Yang Wang ◽  
Yi Zhun Zhu
Keyword(s):  
Rat Brain ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
In Vitro Study ◽  
Artery Occlusion ◽  
Neuroprotective Effects ◽  
Inhibit Lipid Peroxidation ◽  
Cysteine Derivative

Novel Danshensu derivatives (3–8) were designed and synthesized to improve bioactivity based on the strategy of ‘medicinal chemical hybridization’. Our previous studies indicated that these compounds exhibited noticeable cardioprotective activities. Here, we investigate whether these novel Danshensu derivatives exert neuroprotective activities. An in vitro study revealed that these compounds could increase cell viability and reduce LDH (lactate dehydrogenase) leakage. Moreover, Danshensu-cysteine derivative compounds 6 and 8 could significantly inhibit lipid peroxidation of cell membrane and regulate the expression of apoptosis-related protein (Bcl-2, Bax and caspase 3). An in vivo study demonstrated that treatment with compound 6 at 30 mg/kg markedly decreased the infarct volume of MCAO (middle cerebral artery occlusion) insulted rat brain. Furthermore, treatment with compound 6 showed the antioxidant capacity by increasing the activity of SOD (superoxide dismutase) and GPx (glutathione peroxidase) and decreasing the level of MDA (malondialdehyde) and the ROS (reactive oxygen species) production significantly. These results suggested that these novel conjugates exert significant neuroprotective effects as anti-ischaemia agents and those with high potential merit further investigation.

scholarly journals Proof of concept and feasibility studies examining the influence of combination ribose, adenine and allopurinol treatment on stroke outcome in the rat

2017 ◽  
Vol 1 ◽  
pp. 239821281771711 ◽  
Author(s):  
Kiterie M.E. Faller ◽  
Joshua Leach ◽  
Pamela Johnston ◽  
William M. Holmes ◽  
I. Mhairi Macrae ◽  
...  
Keyword(s):  
Cerebral Ischaemia ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
Brain Slices ◽  
Oxidase Inhibitor ◽  
Lesion Volume ◽  
Ischaemic Injury ◽  
Xanthine Oxidase Inhibitor ◽  
Atp Levels

Background: Cerebral ischaemia results in a rapid and profound depletion of adenosine triphosphate (ATP), the energy currency of the cell. This depletion leads to disruption of cellular homeostasis and cell death. Early replenishment of ATP levels might therefore have a neuroprotective effect in the injured brain. We have previously shown that the ATP precursors, D-ribose and adenine (RibAde), restored the reduced ATP levels in rat brain slices to values similar to those measured in the intact rodent brain. The aim of this study was to assess whether RibAde, either alone or in combination with the xanthine oxidase inhibitor allopurinol (RibAdeAll; to further increase the availability of ATP precursors), could improve outcome in an in vivo rodent model of transient cerebral ischaemia. Methods: After 60 min occlusion of the middle cerebral artery, and upon reperfusion, rats were administered saline, RibAde, or RibAdeAll for 6 h. Baseline lesion volume was determined by diffusion-weighted MRI prior to reperfusion and final infarct volume determined by T2-weighted MRI at Day 7. Neurological function was assessed at Days 1, 3 and 7. Results: Ischaemic lesion volume decreased between Days 1 and 7: a 50% reduction was observed for the RibAdeAll group, 38% for the RibAde group and 18% in the animals that received saline. Reductions in lesion size in treatment groups were accompanied by a trend for faster functional recovery. Conclusion: These data support the potential use of ribose, adenine and allopurinol in the treatment of cerebral ischaemic injury, especially since all compounds have been used in man.

scholarly journals Sirt1 Mediates Hyperbaric Oxygen Preconditioning-Induced Ischemic Tolerance in Rat Brain

2013 ◽  
Vol 33 (3) ◽  
pp. 396-406 ◽  
Author(s):  
Wenjun Yan ◽  
Zongping Fang ◽  
Qianzi Yang ◽  
Hailong Dong ◽  
Yan Lu ◽  
...  
Keyword(s):  
Hyperbaric Oxygen ◽  
Cortical Neurons ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
Ischemia Reperfusion ◽  
B Cell Lymphoma ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Class Iii ◽  
Hyperbaric Oxygen Preconditioning

Our previous studies have shown that hyperbaric oxygen preconditioning (HBO-PC) induces tolerance to cerebral ischemia/reperfusion (I/R). This study aimed to investigate whether SirT1, a class III histone deacetylase, is involved in neuroprotection elicited by HBO-PC in animal and cell culture models of ischemia. Rats were subjected to middle cerebral artery occlusion for 120 minutes after HBO-PC (once a day for 5 days). Primary cultured cortical neurons were exposed to 2 hours of HBO-PC after 2 hours of oxygen–glucose deprivation (OGD). We showed that HBO-PC increased SirT1 protein and mRNA expression, promoted neurobehavioral score, reduced infarct volume, and improved morphology at 24 hours and 7 days after cerebral I/R. Neuroprotection of HBO-PC was attenuated by SirT1 inhibitor EX527 and SirT1 knockdown by short interfering RNA (siRNA), whereas it was mimicked by SirT1 activator resveratrol. Furthermore, HBO-PC enhanced SirT1 expression and cell viability and reduced lactate dehydrogenase release 24 hours after OGD/re-oxygenation. The neuroprotective effect of HBO-PC was emulated through upregulating SirT1 and, reversely, attenuated through downregulating SirT1. The modulation of SirT1 was made by adenovirus infection carrying SirT1 or SirT1 siRNA. Besides, SirT1 increased B-cell lymphoma 2 (Bcl-2) expression and decrease cleaved caspase 3. These results indicate that SirT1 mediates HBO-PC-induced tolerance to cerebral I/R through inhibition of apoptosis.

scholarly journals Prunus cerasoides Extract and Its Component Compounds Upregulate Neuronal Neuroglobin Levels, Mediate Antioxidant Effects, and Ameliorate Functional Losses in the Mouse Model of Cerebral Ischemia

Antioxidants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 99
Author(s):  
So-Dam Kim ◽  
Minha Kim ◽  
Hong-Hua Wu ◽  
Byung Kwan Jin ◽  
Myung-Shin Jeon ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Mouse Model ◽  
Infarct Volume ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Novel Approach ◽  
Vehicle Treatment ◽  
Prunus Cerasoides

Prunus cerasoides (PC) has been reported to have antimicrobial and anti-inflammatory properties, but its potential as a neuroprotective agent in a mouse model of cerebral ischemia has not been explored. Considering neuroglobin (Ngb), an endogenous neuroprotective factor, as a novel approach to neuroprotection, in this study, Ngb promoter activity, Ngb expression changes, and antioxidant protection by PC extract (PCE) and PC component compounds (PCCs) were analyzed in oxygen–glucose deprivation (OGD)-treated neurons. In vivo analysis involved transient middle cerebral artery occlusion (tMCAO) in mice with pre- and post-treatment exposure to PCE. Following ischemic stroke induction, neurological behavior scores were obtained, and cellular function-related signals were evaluated in the ischemic infarct areas. In addition to PCE, certain component compounds from PCE also significantly increased Ngb levels and attenuated the intracellular ROS production and cytotoxicity seen with OGD in primary neurons. Administration of PCE reduced the infarct volume and improved neurological deficit scores in ischemic stroke mice compared with the vehicle treatment. Increased Ngb levels in infarct penumbra with PCE treatment were also accompanied by decreased markers of apoptosis (activated p38 and cleaved caspase-3). Our findings point to the benefits of Ngb-mediated neuroprotection via PCE and its antioxidant activity in an ischemic stroke model.

RTN1-C mediates cerebral ischemia/reperfusion injury via modulating autophagy

2020 ◽  
Author(s):  
Jun Ling ◽  
Haijian Cai ◽  
Muya Lin ◽  
Shunli Qi ◽  
Jian Du ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Infarct Volume ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Neurological Deficits ◽  
Cerebral Ischemia Reperfusion

Abstract It has been widely accepted that autophagic cell death exacerbates the progression of cerebral ischemia/reperfusion (I/R). Our previous study revealed that overexpression of reticulon protein 1-C (RTN1-C) is involved in cerebral I/R injury. However, the underlying mechanisms have not been studied intensively. This study was designed to evaluate the effect of RTN1-C on autophagy under cerebral I/R. Using an in vitro oxygen-glucose deprivation followed by reoxygenation and a transient middle cerebral artery occlusion model in rats, we found that the expression of RTN1-C protein was significantly upregulated. We also revealed that RTN1-C knockdown suppressed overactivated autophagy both in vivo and in vitro, as indicated by decreased expressions of autophagic proteins. The number of Beclin-1/propidium iodide-positive cells was significantly less in the LV-shRTN1-C group than in the LV-shNC group. In addition, rapamycin, an activator of autophagy, aggravated cerebral I/R injury. RTN1-C knockdown reduced brain infarct volume, improved neurological deficits, and attenuated cell vulnerability to cerebral I/R injury after rapamycin treatment. Taken together, our findings demonstrated that the modulation of autophagy from RTN1-C may play vital roles in cerebral I/R injury, providing a potential therapeutic treatment for ischemic brain injury.

scholarly journals Ischemia-induced brain damage is enhanced in human renin and angiotensinogen double-transgenic mice

2009 ◽  
Vol 297 (5) ◽  
pp. R1526-R1531 ◽  
Author(s):  
Shuzhen Chen ◽  
Guangze Li ◽  
Wenfeng Zhang ◽  
Jinju Wang ◽  
Curt D. Sigmund ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Injury ◽  
Infarct Volume ◽  
Brain Slices ◽  
Glucose Deprivation ◽  
Optical Signal ◽  
Artery Occlusion ◽  
Neurological Deficits ◽  
Ang Ii ◽  
Cerebral Artery Occlusion

To investigate the role of brain angiotensin II (ANG II) in the pathogenesis of injury following ischemic stroke, mice overexpressing renin and angiotensinogen (R+A+) and their wild-type control animals (R−A−) were used for experimental ischemia studies. Focal brain ischemia was induced by middle cerebral artery occlusion (MCAO). The severity of ischemic injury was determined by measuring neurological deficits and histological damage at 24 and 48 h after MCAO, respectively. To exclude the influence of blood pressure and local collateral blood flow, brain slices were used for oxygen and glucose deprivation (OGD) studies. The severity of OGD-induced damage was determined by measuring indicators of tissue swelling and cell death, the intensity of the intrinsic optical signal (IOS), and the number of propidium iodide (PI) staining cells, respectively. Results showed 1) R+A+ mice showed higher neurological deficit score (3.8 ± 0.5 and 2.5 ± 0.3 for R+A+ and R−A−, respectively, P < 0.01) and larger infarct volume (22.2 ± 1.6% and 14.1 ± 1.2% for R+A+ and R−A−, respectively, P < 0.01); 2) The R+A+ brain slices showed more severe tissue swelling and cell death in the cortex (IOS: 140 ± 6% and 114 ± 10%; PI: 139 ± 20 cells/field and 39 ± 9 cells/field for R+A+ and R−A−, respectively, P < 0.01); 3) treatment with losartan (20 μmol/l) abolished OGD-induced exaggeration of cell injury seen in R+A+ mice. The data indicate that activation of ANG II/AT1 signaling is harmful to brain exposed to ischemia.

scholarly journals PHLPP1 Gene Deletion Protects the Brain from Ischemic Injury

2012 ◽  
Vol 33 (2) ◽  
pp. 196-204 ◽  
Author(s):  
Bo Chen ◽  
Jessica A Van Winkle ◽  
Patrick D Lyden ◽  
Joan H Brown ◽  
Nicole H Purcell
Keyword(s):  
Protein Phosphatase ◽  
Infarct Volume ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Ph Domain ◽  
Akt Activation ◽  
Cerebral Artery Occlusion ◽  
The Brain ◽  
Leucine Rich Repeat Protein

A recently discovered protein phosphatase PHLPP (PH domain Leucine-rich repeat Protein Phosphatase) has been shown to dephosphorylate Akt on its hydrophobic motif (Ser473) thereby decreasing Akt kinase activity. We generated PHLPP1 knockout (KO) mice and used them to explore the ability of enhanced in vivo Akt signaling to protect the brain against ischemic insult. Brains from KO mice subjected to middle cerebral artery occlusion (MCAO) for 2 hours showed significantly greater increases in Akt activity and less neurovascular damage after reperfusion than wild-type (WT) mice. Remarkably, infarct volume in the PHLPP1 KO was significantly reduced compared with WT (12.7 ± 2.7% versus 22.9 ± 3.1%) and this was prevented by Akt inhibition. Astrocytes from KO mice and neurons in which PHLPP1 was downregulated showed enhanced Akt activation and diminished cell death in response to oxygen-glucose deprivation. Thus, deletion of PHLPP1 can enhance Akt activation in neurons and astrocytes, and can significantly increase cell survival and diminish infarct size after MCAO. Inhibition of PHLPP could be a therapeutic approach to minimize damage after focal ischemia.

Resveratrol Reduces Matrix Metalloproteinase-2 Activity Induced by Oxygen-Glucose Deprivation and Reoxygenation in Human Cerebral Microvascular Endothelial Cells

2012 ◽  
Vol 82 (4) ◽  
pp. 267-274 ◽  
Author(s):  
Zahide Cavdar ◽  
Mehtap Y. Egrilmez ◽  
Zekiye S. Altun ◽  
Nur Arslan ◽  
Nilgun Yener ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Neuroprotective Effect ◽  
Ischemia Reperfusion ◽  
Neurovascular Unit ◽  
Glucose Deprivation ◽  
Matrix Metalloproteinase 2 ◽  
Microvascular Endothelial Cells ◽  
Oxygen Glucose Deprivation ◽  
Microvascular Endothelial

The main pathophysiology in cerebral ischemia is the structural alteration in the neurovascular unit, coinciding with neurovascular matrix degradation. Among the human matrix metalloproteinases (MMPs), MMP-2 and -9, known as gelatinases, are the key enzymes for degrading type IV collagen, which is the major component of the basal membrane that surrounds the cerebral blood vessel. In the present study, we investigated the effects of resveratrol on cytotoxicity, reactive oxygen species (ROS), and gelatinases (MMP-2 and -9) in human cerebral microvascular endothelial cells exposed to 6 hours of oxygen-glucose deprivation and a subsequent 24 hours of reoxygenation with glucose (OGD/R), to mimic ischemia/reperfusion in vivo. Lactate dehydrogenase increased significantly, in comparison to that in the normoxia group. ROS was markedly increased in the OGD/R group, compared to normoxia. Correspondingly, ROS was significantly reduced with 50 μM of resveratrol. The proMMP-2 activity in the OGD/R group showed a statistically significant increase from the control cells. Resveratrol preconditioning decreased significantly the proMMP-2 in the cells exposed to OGD/R in comparison to that in the OGD/R group. Our results indicate that resveratrol regulates MMP-2 activity induced by OGD/R via its antioxidant effect, implying a possible mechanism related to the neuroprotective effect of resveratrol.

scholarly journals The hypoxia sensitive metal transcription factor MTF-1 activates NCX1 brain promoter and participates in remote postconditioning neuroprotection in stroke

2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Valeria Valsecchi ◽  
Giusy Laudati ◽  
Ornella Cuomo ◽  
Rossana Sirabella ◽  
Lucio Annunziato ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Brain Ischemia ◽  
Femoral Artery ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
Artery Occlusion ◽  
Sodium Calcium Exchanger ◽  
Protein Levels ◽  
Relevant Role ◽  
Remote Postconditioning

AbstractRemote limb ischemic postconditioning (RLIP) is an experimental strategy in which short femoral artery ischemia reduces brain damage induced by a previous harmful ischemic insult. Ionic homeostasis maintenance in the CNS seems to play a relevant role in mediating RLIP neuroprotection and among the effectors, the sodium-calcium exchanger 1 (NCX1) may give an important contribution, being expressed in all CNS cells involved in brain ischemic pathophysiology. The aim of this work was to investigate whether the metal responsive transcription factor 1 (MTF-1), an important hypoxia sensitive transcription factor, may (i) interact and regulate NCX1, and (ii) play a role in the neuroprotective effect mediated by RLIP through NCX1 activation. Here we demonstrated that in brain ischemia induced by transient middle cerebral occlusion (tMCAO), MTF-1 is triggered by a subsequent temporary femoral artery occlusion (FAO) and represents a mediator of endogenous neuroprotection. More importantly, we showed that MTF-1 translocates to the nucleus where it binds the metal responsive element (MRE) located at −23/−17 bp of Ncx1 brain promoter thus activating its transcription and inducing an upregulation of NCX1 that has been demonstrated to be neuroprotective. Furthermore, RLIP restored MTF-1 and NCX1 protein levels in the ischemic rat brain cortex and the silencing of MTF-1 prevented the increase of NCX1 observed in RLIP protected rats, thus demonstrating a direct regulation of NCX1 by MTF-1 in the ischemic cortex of rat exposed to tMCAO followed by FAO. Moreover, silencing of MTF-1 significantly reduced the neuroprotective effect elicited by RLIP as demonstrated by the enlargement of brain infarct volume observed in rats subjected to RLIP and treated with MTF-1 silencing. Overall, MTF-dependent activation of NCX1 and their upregulation elicited by RLIP, besides unraveling a new molecular pathway of neuroprotection during brain ischemia, might represent an additional mechanism to intervene in stroke pathophysiology.

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