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Poitras M, Doiron A, Plamondon H. Selective estrogen receptor activation prior to global cerebral ischemia in female rats impacts microglial activation and anxiety-like behaviors without effects on CA1 neuronal injury. Behav Brain Res 2024; 470:115094. [PMID: 38844057 DOI: 10.1016/j.bbr.2024.115094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 06/03/2024] [Accepted: 06/03/2024] [Indexed: 06/10/2024]
Abstract
Estrogen receptor (ER) activation by 17-ß estradiol (E2) can attenuate neuronal injury and behavioral impairments following global cerebral ischemia (GCI) in rodents. This study sought to further examine the discrete roles of ERs through characterization of the effects of selective ER activation on post-ischemic pro-inflammatory microglial activation, hippocampal neuronal injury, and anxiety-like behaviors. Forty-six ovariectomized (OVX) adult female Wistar rats received daily s.c injections (100 μg/kg/day) of propylpyrazole triol (PPT; ERα agonist), diarylpropionitrile (DPN; ERβ agonist), G-1 (G-protein coupled ER agonist; GPER), E2 (activating all receptors), or vehicle solution (VEH) for 21 days. After final injection, rats underwent GCI via 4-vessel occlusion (n=8 per group) or sham surgery (n=6, vehicle injections). The Open Field Test (OFT), Elevated Plus Maze (EPM), and Hole Board Test (HBT) assessed anxiety-like behaviors. Microglial activation (Iba1, CD68, CD86) in the basolateral amygdala (BLA), CA1 of the hippocampus, and paraventricular nucleus of the hypothalamus (PVN) was determined 8 days post-ischemia. Compared to sham rats, Iba1 activation and CA1 neuronal injury were increased in all ischemic groups except DPN-treated rats, with PPT-treated ischemic rats also showing increased PVN Iba1-ir expression. Behaviorally, VEH ischemic rats showed slightly elevated anxiety in the EPM compared to sham counterparts, with no significant effects of agonists. While no changes were observed in the OFT, emotion regulation via grooming in the HBT was increased in G-1 rats compared to E2 rats. Our findings support selective ER activation to regulate post-ischemic microglial activation and coping strategies in the HBT, despite minimal impact on hippocampal injury.
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Affiliation(s)
- Marilou Poitras
- Cerebro Vascular Accidents and Behavioral Recovery Laboratory, School of Psychology, University of Ottawa, Ottawa, Canada
| | - Alexandra Doiron
- Cerebro Vascular Accidents and Behavioral Recovery Laboratory, School of Psychology, University of Ottawa, Ottawa, Canada
| | - Hélène Plamondon
- Cerebro Vascular Accidents and Behavioral Recovery Laboratory, School of Psychology, University of Ottawa, Ottawa, Canada.
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Nourhashemi M, Mahmoudzadeh M, Heberle C, Wallois F. Preictal neuronal and vascular activity precedes the onset of childhood absence seizure: direct current potential shifts and their correlation with hemodynamic activity. NEUROPHOTONICS 2023; 10:025005. [PMID: 37114185 PMCID: PMC10128878 DOI: 10.1117/1.nph.10.2.025005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
SIGNIFICANCE AIMS The neurovascular mechanisms underlying the initiation of absence seizures and their dynamics are still not well understood. The objective of this study was to better noninvasively characterize the dynamics of the neuronal and vascular network at the transition from the interictal state to the ictal state of absence seizures and back to the interictal state using a combined electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), and diffuse correlation spectroscopy (DCS) approach. The second objective was to develop hypotheses about the neuronal and vascular mechanisms that propel the networks to the 3-Hz spikes and wave discharges (SWDs) observed during absence seizures. APPROACHES We evaluated the simultaneous changes in electrical (neuronal) and optical dynamics [hemodynamic, with changes in (Hb) and cerebral blood flow] of 8 pediatric patients experiencing 25 typical childhood absence seizures during the transition from the interictal state to the absence seizure by simultaneously performing EEG, fNIRS, and DCS. RESULTS Starting from ∼ 20 s before the onset of the SWD, we observed a transient direct current potential shift that correlated with alterations in functional fNIRS and DCS measurements of the cerebral hemodynamics detecting the preictal changes. DISCUSSION Our noninvasive multimodal approach highlights the dynamic interactions between the neuronal and vascular compartments that take place in the neuronal network near the time of the onset of absence seizures in a very specific cerebral hemodynamic environment. These noninvasive approaches contribute to a better understanding of the electrical hemodynamic environment prior to seizure onset. Whether this may ultimately be relevant for diagnostic and therapeutic approaches requires further evaluation.
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Affiliation(s)
- Mina Nourhashemi
- Université de Picardie Jules Verne, Inserm U1105, GRAMFC, CURS, Amiens, France
| | - Mahdi Mahmoudzadeh
- Université de Picardie Jules Verne, Inserm U1105, GRAMFC, CURS, Amiens, France
- Amiens University Hospital, Pediatric Neurophysiology Unit, Amiens, France
| | - Claire Heberle
- Amiens University Hospital, Pediatric Neurophysiology Unit, Amiens, France
| | - Fabrice Wallois
- Université de Picardie Jules Verne, Inserm U1105, GRAMFC, CURS, Amiens, France
- Amiens University Hospital, Pediatric Neurophysiology Unit, Amiens, France
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3
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Zhao T, Zhong R, Zhang X, Li G, Zhou C, Fang S, Ding Y, Lin W. Efavirenz restored NMDA receptor dysfunction and inhibited epileptic seizures in GluN2A/Grin2a mutant mice. Front Neurosci 2023; 17:1086462. [PMID: 36937661 PMCID: PMC10017539 DOI: 10.3389/fnins.2023.1086462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 02/02/2023] [Indexed: 03/06/2023] Open
Abstract
Introduction N-methyl-D-aspartate receptor (NMDAR) is one of the main receptor of the excitatory neurotransmitter glutamate in the brain, which is the key determinant of the excitatory/inhibitory balance of neural network. GluN2A/GRIN2A is one of the subunits of NMDAR and plays an important role in epilepsy. Approximately 78% of patients with GluN2A/Grin2a mutations have epilepsy, and the underlying mechanism of this association is not well characterized. Methods We constructed a mouse model of hyperthermic seizure, and conducted in vitro and in vivo electrophysiological and behavioral studies to clarify the pathogenic characteristics and mechanism of GluN2A/GRIN2A-V685G mutation. In addition, the drug efavirenz (EFV), which is used to treat HIV infection, was administrated to mutant animals to assess whether it can restore the loss of function. Results Mutant mice showed no significant change in the mRNA or protein expressions of NMDAR compared with wild type (WT) mice. Mice with GluN2A/GRIN2A-V685G mutation exhibited shorter latency to seizure, increased frequency of seizure-like events, decreased peak current and current area of NMDAR excitatory postsynaptic current, and decreased event frequency of micro-inhibitory postsynaptic current, compared to WT mice. They also exhibited decreased threshold, increased amplitude, increased input resistance, and increased root number of action potential. EFV administration reversed these changes. The loss-of-function (LoF) mutation of NMDAR changed the excitatory/inhibitory balance of neural network, rendering animal more prone to seizures. Discussion EFV was indicated to hold its potential in the treatment of inherited epilepsy.
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Affiliation(s)
- Teng Zhao
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Rui Zhong
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Xinyue Zhang
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Guangjian Li
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Chunkui Zhou
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Shaokuan Fang
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
- Shaokuan Fang,
| | - Ying Ding
- Department of Radiology, The First Hospital of Jilin University, Changchun, China
- Ying Ding,
| | - Weihong Lin
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
- *Correspondence: Weihong Lin,
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Lee DA, Lee J, Park KM. Glymphatic system impairment in patients with status epilepticus. Neuroradiology 2022; 64:2335-2342. [PMID: 35835880 DOI: 10.1007/s00234-022-03018-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/08/2022] [Indexed: 12/01/2022]
Abstract
OBJECTIVE The aim of this study was to compare the function of the glymphatic system in patients with status epilepticus (SE) with that in healthy controls by diffusion tensor image analysis along the perivascular space (DTI-ALPS) method. We also investigated the association between glymphatic system function and the clinical characteristics of SE. METHODS We retrospectively enrolled 28 patients with SE and 31 healthy controls matched for age and sex. All study participants underwent diffusion tensor imaging using the same 3-T MRI scanner, and the DTI-ALPS index was calculated. We compared the DTI-ALPS index between the SE group and the control group. We also evaluated the associations of the DTI-ALPS index with etiology and type of SE, age, putative duration of seizure, time interval until MRI, seizure-related changes on diffusion-weighted imaging, and any previous structural lesions. RESULTS The DTI-ALPS index was significantly lower in the SE group than in the control group (1.462 ± 0.297 vs. 1.632 ± 0.270, p = 0.026) and was negatively correlated with age (r = - 0.280, p = 0.032) in the SE group. However, there were no significant between-group differences in the DTI-ALPS index according to other clinical factors. SIGNIFICANCE The finding of a significantly lower DTI-ALPS index in the SE group suggests that the glymphatic system is impaired in patients with SE. DTI-ALPS is a useful tool for evaluation of the function of the glymphatic system in these patients.
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Affiliation(s)
- Dong Ah Lee
- Department of Neurology, Haeundae Paik Hospital, Inje University College of Medicine, Haeundae-ro 875, Haeundae-gu, Busan, 48108, Korea
| | - Joonwon Lee
- Department of Neurology, Haeundae Paik Hospital, Inje University College of Medicine, Haeundae-ro 875, Haeundae-gu, Busan, 48108, Korea
| | - Kang Min Park
- Department of Neurology, Haeundae Paik Hospital, Inje University College of Medicine, Haeundae-ro 875, Haeundae-gu, Busan, 48108, Korea.
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5
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Bauer PR, Tolner EA, Keezer MR, Ferrari MD, Sander JW. Headache in people with epilepsy. Nat Rev Neurol 2021; 17:529-544. [PMID: 34312533 DOI: 10.1038/s41582-021-00516-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2021] [Indexed: 02/06/2023]
Abstract
Epidemiological estimates indicate that individuals with epilepsy are more likely to experience headaches, including migraine, than individuals without epilepsy. Headaches can be temporally unrelated to seizures, or can occur before, during or after an episode; seizures and migraine attacks are mostly not temporally linked. The pathophysiological links between headaches (including migraine) and epilepsy are complex and have not yet been fully elucidated. Correct diagnoses and appropriate treatment of headaches in individuals with epilepsy is essential, as headaches can contribute substantially to disease burden. Here, we review the insights that have been made into the associations between headache and epilepsy over the past 5 years, including information on the pathophysiological mechanisms and genetic variants that link the two disorders. We also discuss the current best practice for the management of headaches co-occurring with epilepsy and highlight future challenges for this area of research.
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Affiliation(s)
- Prisca R Bauer
- Department of Psychosomatic Medicine and Psychotherapy, University Medical Center Freiburg, Freiburg, Germany.
| | - Else A Tolner
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.,Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Mark R Keezer
- Research Centre of the Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada.,School of Public Health, Université de Montréal, Montreal, Quebec, Canada.,Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands
| | - Michel D Ferrari
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Josemir W Sander
- Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands.,NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London, UK.,Chalfont Centre for Epilepsy, Chalfont St Peter, UK
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Hill AS, Jain P, Folan NE, Ben-Shahar Y. The Drosophila ERG channel seizure plays a role in the neuronal homeostatic stress response. PLoS Genet 2019; 15:e1008288. [PMID: 31393878 PMCID: PMC6687100 DOI: 10.1371/journal.pgen.1008288] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 07/04/2019] [Indexed: 11/24/2022] Open
Abstract
Neuronal physiology is particularly sensitive to acute stressors that affect excitability, many of which can trigger seizures and epilepsies. Although intrinsic neuronal homeostasis plays an important role in maintaining overall nervous system robustness and its resistance to stressors, the specific genetic and molecular mechanisms that underlie these processes are not well understood. Here we used a reverse genetic approach in Drosophila to test the hypothesis that specific voltage-gated ion channels contribute to neuronal homeostasis, robustness, and stress resistance. We found that the activity of the voltage-gated potassium channel seizure (sei), an ortholog of the mammalian ERG channel family, is essential for protecting flies from acute heat-induced seizures. Although sei is broadly expressed in the nervous system, our data indicate that its impact on the organismal robustness to acute environmental stress is primarily mediated via its action in excitatory neurons, the octopaminergic system, as well as neuropile ensheathing and perineurial glia. Furthermore, our studies suggest that human mutations in the human ERG channel (hERG), which have been primarily implicated in the cardiac Long QT Syndrome (LQTS), may also contribute to the high incidence of seizures in LQTS patients via a cardiovascular-independent neurogenic pathway.
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Affiliation(s)
- Alexis S. Hill
- Department of Biology, College of the Holy Cross, Worcester, Massachusetts, United States of America
| | - Poorva Jain
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Nicole E. Folan
- Department of Biology, College of the Holy Cross, Worcester, Massachusetts, United States of America
| | - Yehuda Ben-Shahar
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, United States of America
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7
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Héja L, Simon Á, Szabó Z, Kardos J. Feedback adaptation of synaptic excitability via Glu:Na + symport driven astrocytic GABA and Gln release. Neuropharmacology 2019; 161:107629. [PMID: 31103619 DOI: 10.1016/j.neuropharm.2019.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/30/2019] [Accepted: 05/07/2019] [Indexed: 02/08/2023]
Abstract
Glutamatergic transmission composed of the arriving of action potential at the axon terminal, fast vesicular Glu release, postsynaptic Glu receptor activation, astrocytic Glu clearance and Glu→Gln shuttle is an abundantly investigated phenomenon. Despite its essential role, however, much less is known about the consequences of the mechanistic connotations of Glu:Na+ symport. Due to the coupled Na+ transport, Glu uptake results in significantly elevated intracellular astrocytic [Na+] that markedly alters the driving force of other Na+-coupled astrocytic transporters. The resulting GABA and Gln release by reverse transport through the respective GAT-3 and SNAT3 transporters help to re-establish the physiological Na+ homeostasis without ATP dissipation and consequently leads to enhanced tonic inhibition and replenishment of axonal glutamate pool. Here, we place this emerging astrocytic adjustment of synaptic excitability into the centre of future perspectives. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
- László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Ágnes Simon
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Zsolt Szabó
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary.
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8
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Loewen JL, Albertini G, Dahle EJ, Sato H, Smolders IJ, Massie A, Wilcox KS. Genetic and pharmacological manipulation of glial glutamate transporters does not alter infection-induced seizure activity. Exp Neurol 2019; 318:50-60. [PMID: 31022385 DOI: 10.1016/j.expneurol.2019.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 03/19/2019] [Accepted: 04/20/2019] [Indexed: 12/11/2022]
Abstract
The contribution of glial transporters to glutamate movement across the membrane has been identified as a potential target for anti-seizure therapies. Two such glutamate transporters, GLT-1 and system xc-, are expressed on glial cells, and modulation of their expression and function have been identified as a means by which seizures, neuronal injury, and gliosis can be reduced in models of brain injury. While GLT-1 is responsible for the majority of glutamate uptake in the brain, system xc- releases glutamate in the extracellular cleft in exchange for cystine and represents as such the major source of hippocampal extracellular glutamate. Using the Theiler's Murine Encephalomyelitis Virus (TMEV) model of viral-induced epilepsy, we have taken two well-studied approaches, one pharmacological, one genetic, to investigate the potential role(s) of GLT-1 and system xc- in TMEV-induced pathology. Our findings suggest that the methods we utilized to modulate these glial transporters, while effective in other models, are not sufficient to reduce the number or severity of behavioral seizures in TMEV-infected mice. However, genetic knockout of xCT, the specific subunit of system xc-, may have cellular effects, as we observed a slight decrease in neuronal injury caused by TMEV and an increase in astrogliosis in the CA1 region of the hippocampus. Furthermore, xCT knockout caused an increase in GLT-1 expression selectively in the cortex. These findings have significant implications for both the characterization of the TMEV model as well as for future efforts to discover novel and effective anti-seizure drugs.
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Affiliation(s)
- Jaycie L Loewen
- Department of Pharmacology and Toxicology, University of Utah, USA; Interdepartmental Program in Neuroscience, University of Utah, USA
| | - Giulia Albertini
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Belgium
| | - E Jill Dahle
- Department of Pharmacology and Toxicology, University of Utah, USA
| | - Hideyo Sato
- Department of Medical Technology, Niigata University, Japan
| | - Ilse J Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Belgium
| | - Ann Massie
- Department of Pharmaceutical Biotechnology and Molecular Biology, C4N, Vrije Universiteit Brussel, Belgium
| | - Karen S Wilcox
- Department of Pharmacology and Toxicology, University of Utah, USA; Interdepartmental Program in Neuroscience, University of Utah, USA.
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9
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Vargas-Sánchez K, Mogilevskaya M, Rodríguez-Pérez J, Rubiano MG, Javela JJ, González-Reyes RE. Astroglial role in the pathophysiology of status epilepticus: an overview. Oncotarget 2018; 9:26954-26976. [PMID: 29928494 PMCID: PMC6003549 DOI: 10.18632/oncotarget.25485] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 05/09/2018] [Indexed: 12/11/2022] Open
Abstract
Status epilepticus is a medical emergency with elevated morbidity and mortality rates, and represents a leading cause of epilepsy-related deaths. Though status epilepticus can occur at any age, it manifests more likely in children and elderly people. Despite the common prevalence of epileptic disorders, a complete explanation for the mechanisms leading to development of self-limited or long lasting seizures (as in status epilepticus) are still lacking. Apart from neurons, research evidence suggests the involvement of immune and glial cells in epileptogenesis. Among glial cells, astrocytes represent an ideal target for the study of the pathophysiology of status epilepticus, due to their key role in homeostatic balance of the central nervous system. During status epilepticus, astroglial cells are activated by the presence of cytokines, damage associated molecular patterns and reactive oxygen species. The persistent activation of astrocytes leads to a decrease in glutamate clearance with a corresponding accumulation in the synaptic extracellular space, increasing the chance of neuronal excitotoxicity. Moreover, major alterations in astrocytic gap junction coupling, inflammation and receptor expression, facilitate the generation of seizures. Astrocytes are also involved in dysregulation of inhibitory transmission in the central nervous system and directly participate in ionic homeostatic alterations during status epilepticus. In the present review, we focus on the functional and structural changes in astrocytic activity that participate in the development and maintenance of status epilepticus, with special attention on concurrent inflammatory alterations. We also include potential astrocytic treatment targets for status epilepticus.
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Affiliation(s)
- Karina Vargas-Sánchez
- Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | | | - John Rodríguez-Pérez
- Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | - María G Rubiano
- Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | - José J Javela
- Grupo de Clínica y Salud Mental, Programa de Psicología, Universidad Católica de Pereira, Pereira, Colombia
| | - Rodrigo E González-Reyes
- Universidad del Rosario, Escuela de Medicina y Ciencias de la Salud, GI en Neurociencias-NeURos, Bogotá, Colombia
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10
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Walrave L, Pierre A, Albertini G, Aourz N, De Bundel D, Van Eeckhaut A, Vinken M, Giaume C, Leybaert L, Smolders I. Inhibition of astroglial connexin43 hemichannels with TAT-Gap19 exerts anticonvulsant effects in rodents. Glia 2018; 66:1788-1804. [PMID: 29683209 DOI: 10.1002/glia.23341] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 04/04/2018] [Accepted: 04/04/2018] [Indexed: 12/14/2022]
Abstract
Accumulating evidence shows a key function for astrocytic connexin43 (Cx43) signaling in epilepsy. However, the lack of experimental distinction between Cx43 gap junction channels (GJCs) and hemichannels (HCs) has impeded the identification of the exact contribution of either channel configurations to epilepsy. We therefore investigated whether TAT-Gap19, a Cx mimetic peptide that inhibits Cx43 HCs but not the corresponding Cx43 GJCs, influences experimentally induced seizures in rodents. Dye uptake experiments in acute hippocampal slices of mice demonstrated that astroglial Cx43 HCs open in response to the chemoconvulsant pilocarpine and this was inhibited by TAT-Gap19. In vivo, pilocarpine-induced seizures as well as the accompanying increase in D-serine microdialysate levels were suppressed by Cx43 HC inhibition. Moreover, the anticonvulsant action of TAT-Gap19 was reversed by exogenous D-serine administration, suggesting that Cx43 HC inhibition protects against seizures by lowering extracellular D-serine levels. The anticonvulsive properties of Cx43 HC inhibition were further confirmed in electrical seizure mouse models, i.e. an acute 6 Hertz (Hz) model of refractory seizures and a chronic 6 Hz corneal kindling model. Collectively, these results indicate that Cx43 HCs play a role in seizures and underscore their potential as a novel and druggable target in epilepsy treatment.
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Affiliation(s)
- Laura Walrave
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Anouk Pierre
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Giulia Albertini
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Najat Aourz
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Dimitri De Bundel
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Ann Van Eeckhaut
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Christian Giaume
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Paris, 75005, France
| | - Luc Leybaert
- Physiology group, Department of Basic Medical Sciences, Ghent University, De Pintelaan 185, Ghent, 9000, Belgium
| | - Ilse Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
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11
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Salman MM, Sheilabi MA, Bhattacharyya D, Kitchen P, Conner AC, Bill RM, Woodroofe MN, Conner MT, Princivalle AP. Transcriptome analysis suggests a role for the differential expression of cerebral aquaporins and the MAPK signalling pathway in human temporal lobe epilepsy. Eur J Neurosci 2017; 46:2121-2132. [PMID: 28715131 DOI: 10.1111/ejn.13652] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/10/2017] [Accepted: 07/11/2017] [Indexed: 01/12/2023]
Abstract
Epilepsies are common disorders of the central nervous system (CNS), affecting up to 2% of the global population. Pharmaco-resistance is a major clinical challenge affecting about 30% of temporal lobe epilepsy (TLE) patients. Water homeostasis has been shown crucial for regulation of neuronal excitability. The control of water movement is achieved through a family of small integral membrane channel proteins called aquaporins (AQPs). Despite the fact that changes in water homeostasis occur in sclerotic hippocampi of people with TLE, the expression of AQPs in the epileptic brain is not fully characterised. This study uses microarray and ELISA methods to analyse the mRNA and protein expression of the human cerebral AQPs in sclerotic hippocampi (TLE-HS) and adjacent neocortex tissue (TLE-NC) of TLE patients. The expression of AQP1 and AQP4 transcripts was significantly increased, while that of the AQP9 transcript was significantly reduced in TLE-HS compared to TLE-NC. AQP4 protein expression was also increased while expression of AQP1 protein remained unchanged, and AQP9 was undetected. Microarray data analysis identified 3333 differentially regulated genes and suggested the involvement of the MAPK signalling pathway in TLE pathogenesis. Proteome array data validated the translational profile for 26 genes and within the MAPK pathway (e.g. p38, JNK) that were identified as differentially expressed from microarray analysis. ELISA data showed that p38 and JNK inhibitors decrease AQP4 protein levels in cultured human primary cortical astrocytes. Elucidating the mechanism of selective regulation of different AQPs and associated regulatory proteins may provide a new therapeutic approach to epilepsy treatment.
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Affiliation(s)
- Mootaz M Salman
- Biomolecular Sciences Research Centre (BMRC), Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK
| | - Mariam A Sheilabi
- Biomolecular Sciences Research Centre (BMRC), Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK
| | | | - Philip Kitchen
- School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK
| | - Alex C Conner
- School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK
| | - Roslyn M Bill
- School of Life and Health Sciences, Aston University, Birmingham, UK
| | - M Nicola Woodroofe
- Biomolecular Sciences Research Centre (BMRC), Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK
| | - Matthew T Conner
- Biomolecular Sciences Research Centre (BMRC), Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK.,Research Institute of Health Sciences, School of Sciences, University of Wolverhampton, Wolverhampton, UK
| | - Alessandra P Princivalle
- Biomolecular Sciences Research Centre (BMRC), Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK
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12
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Lisovska N, Daribayev Z, Lisovskyy Y, Kussainova K, Austin L, Bulekbayeva S. Pathogenesis of cerebral palsy through the prism of immune regulation of nervous tissue homeostasis: literature review. Childs Nerv Syst 2016; 32:2111-2117. [PMID: 27638717 DOI: 10.1007/s00381-016-3245-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 09/02/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND The cerebral palsy is highly actual issue of pediatrics, causing significant neurological disability. Though the great progress in the neuroscience has been recently achieved, the pathogenesis of cerebral palsy is still poorly understood. METHODS In this work, we reviewed available experimental and clinical data concerning the role of immune cells in pathogenesis of cerebral palsy. Maintaining of homeostasis in nervous tissue and its transformation in case of periventricular leukomalacia were analyzed. RESULTS The reviewed data demonstrate involvement of immune regulatory cells in the formation of nervous tissue imbalance and chronicity of inborn brain damage. The supported opinion, that periventricular leukomalacia is not a static phenomenon, but developing process, encourages our optimism about the possibility of its correction. CONCLUSIONS The further studies of changes of the nervous and immune systems in cerebral palsy are needed to create fundamentally new directions of the specific therapy and individual schemes of rehabilitation.
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Affiliation(s)
- Natalya Lisovska
- Republican Children's Rehabilitation Center, Turan str., 36, Astana, Kazakhstan, 010000.
| | - Zholtay Daribayev
- Republican Children's Rehabilitation Center, Turan str., 36, Astana, Kazakhstan, 010000
| | - Yevgeny Lisovskyy
- Republican Children's Rehabilitation Center, Turan str., 36, Astana, Kazakhstan, 010000
| | - Kenzhe Kussainova
- Republican Children's Rehabilitation Center, Turan str., 36, Astana, Kazakhstan, 010000
| | - Lana Austin
- Department of Pediatrics, Parirenyatwa Group of hospitals, Harare, Zimbabwe
| | - Sholpan Bulekbayeva
- Republican Children's Rehabilitation Center, Turan str., 36, Astana, Kazakhstan, 010000
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13
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Blood-brain barrier, bulk flow, and interstitial clearance in epilepsy. J Neurosci Methods 2015; 260:118-24. [PMID: 26093166 DOI: 10.1016/j.jneumeth.2015.06.011] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 06/10/2015] [Accepted: 06/11/2015] [Indexed: 11/21/2022]
Abstract
Understanding the pathophysiology of epilepsy implies elucidating the neurovascular modifications occurring before or at time of seizures. Cerebrovascular dysfunction provokes or sustains seizures and loss of selective blood-brain barrier (BBB) permeability is a modulator of seizure threshold. However, cerebrovascular pathology in epilepsy extends beyond BBB "leakage" to encompass vascular and parenchymal events. Whenever abnormal accumulation of protein is observed surrounding brain blood vessels, BBB disruption (BBBD) was invoked. Recent clinical and laboratory findings challenged an exclusive role of BBBD in perivascular accumulation of serum-derived products. The circulation of interstitial fluid (ISF) and its bulk flow have emerged as candidate mechanisms which play a role in clearance of CNS waste. Although controversy exists, changes of ISF flow may contribute to CNS disorders through a mechanism encompassing incomplete parenchymal clearance and accompanying accumulation of toxic byproducts. We summarize the evidence in favor and against ISF bulk flow and propose a scenario where abnormal ISF in the epileptic brain allows accumulation of brain protein, sustaining pathophysiology and altering the pharmacology of antiepileptic drugs. We also describe the methods routinely used to dissect out the contribution of BBB-dependent, vascular or paracellular mechanisms to altered neuronal excitability.
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14
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Gulyaeva NV. Neuronal plasticity and epilepsy: modern concepts and mechanisms of epilepsy and depression comorbidity. Zh Nevrol Psikhiatr Im S S Korsakova 2015; 115:148-153. [DOI: 10.17116/jnevro2015115112148-153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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15
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Paiva WS, Mello LE. Posttraumatic epilepsy: current and emerging treatment options. Neuropsychiatr Dis Treat 2014; 10:2159-61. [PMID: 25419140 PMCID: PMC4235475 DOI: 10.2147/ndt.s73929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
| | - Luiz Eugênio Mello
- Department of Physiology, Federal University of São Paulo, São Paulo, Brazil
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