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Kuriakose D, Xiao Z. Pathophysiology and Treatment of Stroke: Present Status and Future Perspectives. Int J Mol Sci 2020; 21:E7609. [PMID: 33076218 PMCID: PMC7589849 DOI: 10.3390/ijms21207609] [Citation(s) in RCA: 391] [Impact Index Per Article: 97.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/08/2020] [Accepted: 10/13/2020] [Indexed: 12/14/2022] Open
Abstract
Stroke is the second leading cause of death and a major contributor to disability worldwide. The prevalence of stroke is highest in developing countries, with ischemic stroke being the most common type. Considerable progress has been made in our understanding of the pathophysiology of stroke and the underlying mechanisms leading to ischemic insult. Stroke therapy primarily focuses on restoring blood flow to the brain and treating stroke-induced neurological damage. Lack of success in recent clinical trials has led to significant refinement of animal models, focus-driven study design and use of new technologies in stroke research. Simultaneously, despite progress in stroke management, post-stroke care exerts a substantial impact on families, the healthcare system and the economy. Improvements in pre-clinical and clinical care are likely to underpin successful stroke treatment, recovery, rehabilitation and prevention. In this review, we focus on the pathophysiology of stroke, major advances in the identification of therapeutic targets and recent trends in stroke research.
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Affiliation(s)
| | - Zhicheng Xiao
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, VIC 3800, Australia;
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2
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Vondrakova K, Novotny P, Kubova H, Posusta A, Boron J, Faberova V, Fabene PF, Burchfiel J, Tsenov G. Electrographic seizures induced by activation of ET A and ET B receptors following intrahippocampal infusion of endothelin-1 in immature rats occur by different mechanisms. Exp Neurol 2020; 328:113255. [PMID: 32084451 DOI: 10.1016/j.expneurol.2020.113255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 02/03/2020] [Accepted: 02/18/2020] [Indexed: 11/24/2022]
Abstract
We have demonstrated previously that activation of either the ETA or ETB receptor can induce acute electrographic seizures following the intrahippocampal infusion of endothelin-1 (ET-1) in immature (P12) rats. We also demonstrated that activation of the ETA receptor is associated with marked focal ischemia, while activation of the ETB receptor is not. Exploring the mechanisms underlying seizures induced by these two ET-1 receptor interactions can potentially provide insight into how focal ischemia in immature animals produces seizures and whether ischemiarelated seizures differ from seizures not associated with ischemia. To explore these seizure mechanisms we used microdialysis to determine biomarkers associated with seizures in P12 rats following the intrahippocampal infusion of two different agents: (1) ET-1, which activates both the ETA and ETB receptors and causes focal ischemia and (2) Ala-ET-1, which selectively activates only the ETB receptor and does not cause ischemia. Our results show that seizures associated with combined ETA and ETB receptor activation (and ischemia) have a different temporal distribution and microdialysis profile from seizures associated with ETB activation alone (and without ischemia). Seizures with combined activation peak within the first hour after infusion and the microdialysis profile is characterized by a significant increase in the ratio of glutamic acid to GABA. By contrast, seizures with activation of only the ETB receptor peak in the second hour after infusion and microdialysis shows a significant increase in the ratio of leukotriene B4 to prostaglandin E2. These findings suggest that ischemia-related seizures in immature animals involve an imbalance of excitation and inhibition, while non-ischemiarelated seizures involve an inflammatory process resulting from an excess of leukotrienes.
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Affiliation(s)
- Katerina Vondrakova
- Department of Developmental Epileptology, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Faculty of Science, Charles university in Prague, Albertov 6, 12843 Prague, Czech Republic; National Institute of Mental Health, Topolova 748, 25067 Klecany, Czech Republic
| | - Petr Novotny
- Essence Line, Plzeňská 130/221, 150 00 Prague 5, Czech Republic
| | - Hana Kubova
- Department of Developmental Epileptology, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic
| | - Antonin Posusta
- Department of Developmental Epileptology, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic
| | - Jan Boron
- Essence Line, Plzeňská 130/221, 150 00 Prague 5, Czech Republic
| | - Veronika Faberova
- Department of Developmental Epileptology, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Veterinary Clinic Well-vet, 14100 Prague, Czech Republic
| | - Paolo Francesco Fabene
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada le Grazie 8, 37134 Verona, Italy; INN, Istituto Nazionale delle Neuroscienze, Verona, Italy
| | - James Burchfiel
- Strong Epilepsy Center, Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 673, Rochester, NY 14642, USA
| | - Grygoriy Tsenov
- Department of Developmental Epileptology, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; National Institute of Mental Health, Topolova 748, 25067 Klecany, Czech Republic; Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Strada le Grazie 8, 37134 Verona, Italy.
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Rauti R, Medelin M, Newman L, Vranic S, Reina G, Bianco A, Prato M, Kostarelos K, Ballerini L. Graphene Oxide Flakes Tune Excitatory Neurotransmission in Vivo by Targeting Hippocampal Synapses. NANO LETTERS 2019; 19:2858-2870. [PMID: 30983361 DOI: 10.1021/acs.nanolett.8b04903] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Synapses compute and transmit information to connect neural circuits and are at the basis of brain operations. Alterations in their function contribute to a vast range of neuropsychiatric and neurodegenerative disorders and synapse-based therapeutic intervention, such as selective inhibition of synaptic transmission, may significantly help against serious pathologies. Graphene is a two-dimensional nanomaterial largely exploited in multiple domains of science and technology, including biomedical applications. In hippocampal neurons in culture, small graphene oxide nanosheets (s-GO) selectively depress glutamatergic activity without altering cell viability. Glutamate is the main excitatory neurotransmitter in the central nervous system and growing evidence suggests its involvement in neuropsychiatric disorders. Here we demonstrate that s-GO directly targets the release of presynaptic vesicle. We propose that s-GO flakes reduce the availability of transmitter, via promoting its fast release and subsequent depletion, leading to a decline ofglutamatergic neurotransmission. We injected s-GO in the hippocampus in vivo, and 48 h after surgery ex vivo patch-clamp recordings from brain slices show a significant reduction in glutamatergic synaptic activity in respect to saline injections.
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Affiliation(s)
- Rossana Rauti
- Neuron Physiology and Technology Lab , International School for Advanced Studies (SISSA), Neuroscience , 34136 Trieste Italy
| | - Manuela Medelin
- Neuron Physiology and Technology Lab , International School for Advanced Studies (SISSA), Neuroscience , 34136 Trieste Italy
- Life Science Department , University of Trieste , 34127 Trieste Italy
| | - Leon Newman
- Nanomedicine Lab, Faculty of Biology, Medicine and Health, and National Graphene Institute , University of Manchester , AV Hill Building, Manchester M13 9PL , United Kingdom
| | - Sandra Vranic
- Nanomedicine Lab, Faculty of Biology, Medicine and Health, and National Graphene Institute , University of Manchester , AV Hill Building, Manchester M13 9PL , United Kingdom
| | - Giacomo Reina
- CNRS, Immunology, Immunopathology, and Therapeutic Chemistry , University of Strasbourg , UPR 3572, 67000 Strasbourg , France
| | - Alberto Bianco
- CNRS, Immunology, Immunopathology, and Therapeutic Chemistry , University of Strasbourg , UPR 3572, 67000 Strasbourg , France
| | - Maurizio Prato
- Department of Chemical and Pharmaceutical Sciences , University of Trieste , 34127 Trieste , Italy
- Nanobiotechnology Laboratory , CIC biomaGUNE , 00685 San Sebastiàn , Spain
- Ikerbasque, Basque Foundation for Science , 48013 Bilbao , Spain
| | - Kostas Kostarelos
- Nanomedicine Lab, Faculty of Biology, Medicine and Health, and National Graphene Institute , University of Manchester , AV Hill Building, Manchester M13 9PL , United Kingdom
| | - Laura Ballerini
- Neuron Physiology and Technology Lab , International School for Advanced Studies (SISSA), Neuroscience , 34136 Trieste Italy
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4
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Rodent Models of Developmental Ischemic Stroke for Translational Research: Strengths and Weaknesses. Neural Plast 2019; 2019:5089321. [PMID: 31093271 PMCID: PMC6476045 DOI: 10.1155/2019/5089321] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 12/19/2018] [Accepted: 02/06/2019] [Indexed: 12/25/2022] Open
Abstract
Cerebral ischemia can occur at any stage in life, but clinical consequences greatly differ depending on the developmental stage of the affected brain structures. Timing of the lesion occurrence seems to be critical, as it strongly interferes with neuronal circuit development and determines the way spontaneous plasticity takes place. Translational stroke research requires the use of animal models as they represent a reliable tool to understand the pathogenic mechanisms underlying the generation, progression, and pathological consequences of a stroke. Moreover, in vivo experiments are instrumental to investigate new therapeutic strategies and the best temporal window of intervention. Differently from adults, very few models of the human developmental stroke have been characterized, and most of them have been established in rodents. The models currently used provide a better understanding of the molecular factors involved in the effects of ischemia; however, they still hold many limitations due to matching developmental stages across different species and the complexity of the human disorder that hardly can be described by segregated variables. In this review, we summarize the key factors contributing to neonatal brain vulnerability to ischemic strokes and we provide an overview of the advantages and limitations of the currently available models to recapitulate different aspects of the human developmental stroke.
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Mundugaru R, Sivanesan S, Popa-Wagner A, Udaykumar P, Kirubagaran R, KP G, Vidyadhara D. Pluchea lanceolata protects hippocampal neurons from endothelin-1 induced ischemic injury to ameliorate cognitive deficits. J Chem Neuroanat 2018; 94:75-85. [DOI: 10.1016/j.jchemneu.2018.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/24/2018] [Accepted: 09/27/2018] [Indexed: 12/23/2022]
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Spatial Dynamics of Vascular and Biochemical Injury in Rat Hippocampus Following Striatal Injury and Aβ Toxicity. Mol Neurobiol 2018; 56:2714-2727. [DOI: 10.1007/s12035-018-1225-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 07/05/2018] [Indexed: 01/09/2023]
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7
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Hippocampal infusion of lipopolysaccharide induces immune responses and results in seizures in rats. Neuroreport 2017; 28:200-207. [DOI: 10.1097/wnr.0000000000000744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lopes MW, Sapio MR, Leal RB, Fricker LD. Knockdown of Carboxypeptidase A6 in Zebrafish Larvae Reduces Response to Seizure-Inducing Drugs and Causes Changes in the Level of mRNAs Encoding Signaling Molecules. PLoS One 2016; 11:e0152905. [PMID: 27050163 PMCID: PMC4822968 DOI: 10.1371/journal.pone.0152905] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 03/21/2016] [Indexed: 12/19/2022] Open
Abstract
Carboxypeptidase A6 (CPA6) is an extracellular matrix metallocarboxypeptidase that modulates peptide and protein function by removal of hydrophobic C-terminal amino acids. Mutations in the human CPA6 gene that reduce enzymatic activity in the extracellular matrix are associated with febrile seizures, temporal lobe epilepsy, and juvenile myoclonic epilepsy. The characterization of these human mutations suggests a dominant mode of inheritance by haploinsufficiency through loss of function mutations, however the total number of humans with pathologic mutations in CPA6 identified to date remains small. To better understand the relationship between CPA6 and seizures we investigated the effects of morpholino knockdown of cpa6 mRNA in zebrafish (Danio rerio) larvae. Knockdown of cpa6 mRNA resulted in resistance to the effect of seizure-inducing drugs pentylenetetrazole and pilocarpine on swimming behaviors. Knockdown of cpa6 mRNA also reduced the levels of mRNAs encoding neuropeptide precursors (bdnf, npy, chga, pcsk1nl, tac1, nts, edn1), a neuropeptide processing enzyme (cpe), transcription factor (c-fos), and molecules implicated in glutamatergic signaling (grin1a and slc1a2b). Treatment of zebrafish embryos with 60 mM pilocarpine for 1 hour led to reductions in levels of many of the same mRNAs when measured 1 day after pilocarpine exposure, except for c-fos which was elevated 1 day after pilocarpine treatment. Pilocarpine treatment, like cpa6 knockdown, led to a reduced sensitivity to pentylenetetrazole when tested 1 day after pilocarpine treatment. Taken together, these results add to mounting evidence that peptidergic systems participate in the biological effects of seizure-inducing drugs, and are the first in vivo demonstration of the molecular and behavioral consequences of cpa6 insufficiency.
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Affiliation(s)
- Mark William Lopes
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Matthew R. Sapio
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Rodrigo B. Leal
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Lloyd D. Fricker
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- * E-mail:
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Hypoxanthine Intrastriatal Administration Alters Neuroinflammatory Profile and Redox Status in Striatum of Infant and Young Adult Rats. Mol Neurobiol 2016; 54:2790-2800. [DOI: 10.1007/s12035-016-9866-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/17/2016] [Indexed: 01/26/2023]
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10
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Tsenov G, Vondrakova K, Otahal J, Burchfiel J, Kubova H. Activation of either the ETA or the ETB receptors is involved in the development of electrographic seizures following intrahippocampal infusion of the endothelin-1 in immature rats. Exp Neurol 2014; 265:40-7. [PMID: 25542981 DOI: 10.1016/j.expneurol.2014.12.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Revised: 11/28/2014] [Accepted: 12/17/2014] [Indexed: 10/24/2022]
Abstract
The period around birth is a risky time for stroke in infants, which is associated with two major acute and subacute processes: anatomical damage and seizures. It is unclear as to what extent each of these processes independently contributes to poor outcome. Furthermore, it is unclear whether there is an interaction between the two processes - does seizure activity cause additional brain damage beyond that produced by ischemia and/or does brain damage foster seizures? The model of focal cerebral ischemia induced by the intrahippocampal infusion of endothelin-1 (ET-1) in 12-day-old rat was used to examine the role of the endothelin receptors in the development of focal ischemia, symptomatic acute seizures and neurodegeneration. ET-1 (40pmol/μl) was infused either alone or co-administered with selective antagonists of ETA (BQ123; 70nmol/μl) or ETB receptors (BQ788; 70nmol/1μl). Effects of activation of ETB receptors were studied using selective agonist 4-Ala-ET-1 (40pmol/1μl). Regional cerebral blood flow (rCBF) and tissue oxygenation (pO2) were measured in anesthetized animals with a Doppler-flowmeter and a pO2-sensor, respectively. Seizure development was assessed with video-EEG in freely moving rats. Controls received the corresponding volume of the appropriate vehicle (10mM PBS or 0.01% DMSO-PBS solution; pH7.4). The extent of hippocampal lesion was determined using FluoroJade B staining performed 24h after ET-1 infusion. Infusion of ET-1 or ET-1+ETB receptor antagonist reduced rCBF to ~25% and pO2 to ~10% for about 1.5h, whereas selective ETB agonist, ET-1+ETA antagonist and the PBS vehicle had only negligible effect on the rCBF and pO2 levels. Reduction of rCBF was associated with the development of lesion in the injected hippocampus. In all groups, except sham operated and PBS controls, epileptiform activity was observed after activation of the ETA or the ETB receptors. The data revealed a positive correlation between the severity of morphological damage and all the measured seizure parameters (seizure frequency, average and total seizure duration) in the ET-1 group. In addition, the severity of morphological damage positively correlated with the average seizure duration in animals after infusion of ET-1+ETA receptor antagonist or after infusion of ET-1+ETB receptor antagonist. Our results indicate that the activation of ETA receptors is crucial for ischemia development, however either ETA or ETB receptors mediate the development of seizures following the application of ET-1 in immature rats. The dissociation between the ischemic-producing and seizure-producing processes suggests that damage is not necessary to induce seizures, although it may exacerbate them.
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Affiliation(s)
- Grygoriy Tsenov
- Department of Developmental Epileptology, Institute of Physiology, v.v.i., Academy of Sciences of the Czech Republic, Videnska 1083, Prague CZ-14220, Czech Republic.
| | - Katerina Vondrakova
- Department of Developmental Epileptology, Institute of Physiology, v.v.i., Academy of Sciences of the Czech Republic, Videnska 1083, Prague CZ-14220, Czech Republic
| | - Jakub Otahal
- Department of Developmental Epileptology, Institute of Physiology, v.v.i., Academy of Sciences of the Czech Republic, Videnska 1083, Prague CZ-14220, Czech Republic
| | - James Burchfiel
- Strong Epilepsy Center, Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 673, Rochester, NY 14642, USA
| | - Hana Kubova
- Department of Developmental Epileptology, Institute of Physiology, v.v.i., Academy of Sciences of the Czech Republic, Videnska 1083, Prague CZ-14220, Czech Republic
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Kleteckova L, Tsenov G, Kubova H, Stuchlik A, Vales K. Neuroprotective effect of the 3α5β-pregnanolone glutamate treatment in the model of focal cerebral ischemia in immature rats. Neurosci Lett 2014; 564:11-5. [DOI: 10.1016/j.neulet.2014.01.057] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 01/20/2014] [Accepted: 01/29/2014] [Indexed: 01/17/2023]
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12
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Li K, Yamamoto M, Chan SJ, Chiam MY, Qin W, Wong PTH, Yim EKF, Tang BZ, Liu B. Organic nanoparticles with aggregation-induced emission for tracking bone marrow stromal cells in the rat ischemic stroke model. Chem Commun (Camb) 2014; 50:15136-9. [DOI: 10.1039/c4cc06921h] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fluorescent nanoparticles with aggregation-induced emission were successfully used for tracking bone marrow-derived mesenchymal stromal cells in rats with ischemic stroke.
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Affiliation(s)
- Kai Li
- Institute of Materials Research and Engineering
- A*STAR
- , Singapore 117602
| | - Mie Yamamoto
- Department of Pharmacology
- Center for Translational Medicine
- Yong Loo Lin School of Medicine
- National University Health System
- National University of Singapore
| | - Su Jing Chan
- Department of Pharmacology
- Center for Translational Medicine
- Yong Loo Lin School of Medicine
- National University Health System
- National University of Singapore
| | - Mun Yee Chiam
- Department of Biomedical Engineering
- National University of Singapore
- , Singapore 117575
| | - Wei Qin
- Department of Chemistry
- Division of Biomedical Engineering
- Institute for Advanced Study
- State Key Laboratory of Molecular Neuroscience, and Institute of Molecular Functional Materials
- The Hong Kong University of Science & Technology
| | - Peter Tsun Hon Wong
- Department of Pharmacology
- Center for Translational Medicine
- Yong Loo Lin School of Medicine
- National University Health System
- National University of Singapore
| | - Evelyn King Fai Yim
- Department of Biomedical Engineering
- National University of Singapore
- , Singapore 117575
- Mechanobiology Institute Singapore
- National University of Singapore
| | - Ben Zhong Tang
- Department of Chemistry
- Division of Biomedical Engineering
- Institute for Advanced Study
- State Key Laboratory of Molecular Neuroscience, and Institute of Molecular Functional Materials
- The Hong Kong University of Science & Technology
| | - Bin Liu
- Institute of Materials Research and Engineering
- A*STAR
- , Singapore 117602
- Department of Chemical and Biomolecular Engineering
- National University of Singapore
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KONOPKOVÁ R, VILAGI I, BORBELY S, KUBOVÁ H, OTÁHAL J. Effect of Endothelin-1 on the Excitability of Rat Cortical and Hippocampal Slices In Vitro. Physiol Res 2012; 61:215-9. [DOI: 10.33549/physiolres.932218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Endothelin-1 (ET-1) is a neuroactive protein produced in most brain cell types and participates in regulation of cerebral blood flow and blood pressure. In addition to its vascular effects, ET-1 affects synaptic and nonsynaptic neuronal and glial functions. Direct application of ET-1 to the hippocampus of immature rats results in cerebral ischemia, acute seizures, and epileptogenesis. Here, we investigated whether ET-1 itself modifies the excitability of hippocampal and cortical circuitry and whether acute seizures observed in vivo are due to nonvascular actions of ET-1. We used acute hippocampal and cortical slices that were preincubated with ET-1 (20 µM) for electrophysiological recordings. None of the slices preincubated with ET-1 exhibited spontaneous epileptic activity. The slope of the stimulus intensity-evoked response (input-output) curve and shape of the evoked response did not differ between ET-1-pretreated and control groups, suggesting no changes in excitability after ET-1 treatment. The threshold for eliciting an evoked response was not significantly increased in either hippocampal or cortical regions when pretreated with ET-1. Our data suggest that acute seizures after intrahippocampal application of ET-1 in rats are likely caused by ischemia rather than by a direct action of ET-1 on brain tissue.
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Affiliation(s)
| | | | | | | | - J. OTÁHAL
- Department of Developmental Epileptology, Institute of Physiology of the Academy of Sciences of the Czech Republic, Prague, Czech Republic
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Abstract
The incidence of epilepsy is at its highest in childhood and seizures can persist for a lifetime. As brain tissue from pediatric patients with epilepsy is rarely available, the analysis of molecular and cellular changes during epileptogenesis, which could serve as targets for treatment approaches, has to rely largely on the analysis of tissue from animal models. However, these data have to be analyzed in the context of the developmental stage when the insult occurs. Here we review the current status of the available animal models, the molecular analysis done in these models, as well as treatment attempts to prevent epileptogenesis in the immature brain. Considering that epilepsy is one of the major childhood neurological diseases, it is remarkable how little is known on epileptogenesis in the immature brain at a molecular level. It is a true challenge for the future to expand the armamentarium of clinically relevant animal models, and systematic analysis of molecular and cellular data to enhance the probability of developing syndrome specific antiepileptogenic treatments and biomarkers for acquired pediatric epileptogenesis.
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Faraji J, Sutherland RJ, Metz GA. Stress precipitates functional deficits following striatal silent stroke: A synergistic effect. Exp Neurol 2011; 232:251-60. [DOI: 10.1016/j.expneurol.2011.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2011] [Revised: 09/03/2011] [Accepted: 09/09/2011] [Indexed: 10/17/2022]
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16
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Repeated hypoxic episodes induce seizures and alter hippocampal network activities in mice. Neuroscience 2009; 161:599-613. [DOI: 10.1016/j.neuroscience.2009.03.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 02/08/2009] [Accepted: 03/15/2009] [Indexed: 11/23/2022]
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