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Tanaka M, Vécsei L. A Decade of Dedication: Pioneering Perspectives on Neurological Diseases and Mental Illnesses. Biomedicines 2024; 12:1083. [PMID: 38791045 PMCID: PMC11117868 DOI: 10.3390/biomedicines12051083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 05/11/2024] [Indexed: 05/26/2024] Open
Abstract
Welcome to Biomedicines' 10th Anniversary Special Issue, a journey through the human mind's labyrinth and complex neurological pathways [...].
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Affiliation(s)
- Masaru Tanaka
- HUN-REN-SZTE Neuroscience Research Group, Hungarian Research Network, University of Szeged, Danube Neuroscience Research Laboratory, Tisza Lajos krt. 113, H-6725 Szeged, Hungary;
| | - László Vécsei
- HUN-REN-SZTE Neuroscience Research Group, Hungarian Research Network, University of Szeged, Danube Neuroscience Research Laboratory, Tisza Lajos krt. 113, H-6725 Szeged, Hungary;
- Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary
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2
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Schneider MF, Vogt M, Scheuermann J, Müller V, Fischer-Hentrich AHL, Kremer T, Lugert S, Metzger F, Kudernatsch M, Kluger G, Hartlieb T, Noachtar S, Vollmar C, Kunz M, Tonn JC, Coras R, Blümcke I, Pace C, Heinen F, Klein C, Potschka H, Borggraefe I. Brain expression profiles of two SCN1A antisense RNAs in children and adolescents with epilepsy. Transl Neurosci 2024; 15:20220330. [PMID: 38283997 PMCID: PMC10811528 DOI: 10.1515/tnsci-2022-0330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 01/30/2024] Open
Abstract
Objective Heterozygous mutations within the voltage-gated sodium channel α subunit (SCN1A) are responsible for the majority of cases of Dravet syndrome (DS), a severe developmental and epileptic encephalopathy. Development of novel therapeutic approaches is mandatory in order to directly target the molecular consequences of the genetic defect. The aim of the present study was to investigate whether cis-acting long non-coding RNAs (lncRNAs) of SCN1A are expressed in brain specimens of children and adolescent with epilepsy as these molecules comprise possible targets for precision-based therapy approaches. Methods We investigated SCN1A mRNA expression and expression of two SCN1A related antisense RNAs in brain tissues in different age groups of pediatric non-Dravet patients who underwent surgery for drug resistant epilepsy. The effect of different antisense oligonucleotides (ASOs) directed against SCN1A specific antisense RNAs on SCN1A expression was tested. Results The SCN1A related antisense RNAs SCN1A-dsAS (downstream antisense, RefSeq identifier: NR_110598) and SCN1A-usAS (upstream AS, SCN1A-AS, RefSeq identifier: NR_110260) were widely expressed in the brain of pediatric patients. Expression patterns revealed a negative correlation of SCN1A-dsAS and a positive correlation of lncRNA SCN1A-usAS with SCN1A mRNA expression. Transfection of SK-N-AS cells with an ASO targeted against SCN1A-dsAS was associated with a significant enhancement of SCN1A mRNA expression and reduction in SCN1A-dsAS transcripts. Conclusion These findings support the role of SCN1A-dsAS in the suppression of SCN1A mRNA generation. Considering the haploinsufficiency in genetic SCN1A related DS, SCN1A-dsAS is an interesting target candidate for the development of ASOs (AntagoNATs) based precision medicine therapeutic approaches aiming to enhance SCN1A expression in DS.
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Affiliation(s)
- Marius Frederik Schneider
- Division of Molecular Biology, Biomedical Center Munich, Ludwig Maximilians University, Munich, Germany
- International Max Planck Research School (IMPRS) for Molecular Life Sciences, Planegg-Martinsried, Germany
| | | | - Johanna Scheuermann
- Division of Molecular Biology, Biomedical Center Munich, Ludwig Maximilians University, Munich, Germany
| | - Veronika Müller
- Division of Molecular Biology, Biomedical Center Munich, Ludwig Maximilians University, Munich, Germany
| | | | - Thomas Kremer
- Roche Pharmaceutical Research and Early Development, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Sebastian Lugert
- Roche Pharmaceutical Research and Early Development, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd, Basel, Switzerland
| | | | - Manfred Kudernatsch
- Clinic for Neurosurgery, Schoen-Klinik Vogtareuth, Germany
- Paracelsus Medical University, Salzburg, Austria
| | - Gerhard Kluger
- Paracelsus Medical University, Salzburg, Austria
- Neuropediatric Clinic and Clinic for Neurorehabilitation, Epilepsy Center for Children and Adolescents, Schoen-Klinik Vogtareuth, Germany
| | - Till Hartlieb
- Paracelsus Medical University, Salzburg, Austria
- Neuropediatric Clinic and Clinic for Neurorehabilitation, Epilepsy Center for Children and Adolescents, Schoen-Klinik Vogtareuth, Germany
| | - Soheyl Noachtar
- Department of Neurology, Comprehensive Epilepsy Center, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
| | - Christian Vollmar
- Department of Neurology, Comprehensive Epilepsy Center, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
- Comprehensive Epilepsy Center, Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Department of Pediatrics, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
| | - Mathias Kunz
- Department of Neurosurgery, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
| | - Jörg Christian Tonn
- Department of Neurosurgery, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
| | - Roland Coras
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Claudia Pace
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilians University, Munich, Germany
| | - Florian Heinen
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Department of Pediatrics, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
| | - Christoph Klein
- Department of Pediatrics, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilians University, Munich, Germany
| | - Ingo Borggraefe
- Comprehensive Epilepsy Center, Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Department of Pediatrics, University Hospital of Munich, Ludwig Maximilians University, Munich, Germany
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3
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Dardiotis E, Skouras P, Varvarelis OP, Aloizou AM, Hernández AF, Liampas I, Rikos D, Dastamani M, Golokhvast KS, Bogdanos DP, Tsatsakis A, Siokas V, Mitsias PD, Hadjigeorgiou GM. Pesticides and tremor: An overview of association, mechanisms and confounders. ENVIRONMENTAL RESEARCH 2023; 229:115442. [PMID: 36758916 DOI: 10.1016/j.envres.2023.115442] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 02/06/2023] [Accepted: 02/06/2023] [Indexed: 05/06/2023]
Abstract
Pesticides are a heterogeneous class of chemicals mainly used for the protection of crops from pests. Because of their very widespread use, acute or/and chronic exposure to these chemicals can lead to a plethora of sequelae inflicting diseases, many of which involve the nervous system. Tremor has been associated with pesticide exposure in human and animal studies. This review is aimed at assessing the studies currently available on the association between the various types of pesticides/insecticides and tremor, while also accounting for potential confounding factors. To our knowledge, this is the first coherent review on the subject. After appraising the available evidence, we call for more intensive research on this topic, as well as intonate the need of implementing future preventive measures to protect the exposed populations and to reduce potential disabilities and social drawbacks.
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Affiliation(s)
- Efthimios Dardiotis
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece.
| | - Panagiotis Skouras
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Orfeas-Petros Varvarelis
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Athina-Maria Aloizou
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Antonio F Hernández
- Department of Legal Medicine and Toxicology, University of Granada School of Medicine, Granada, Spain; Health Research Institute of Granada (ibs.GRANADA), Granada, Spain; Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), Madrid, Spain
| | - Ioannis Liampas
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Dimitrios Rikos
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Metaxia Dastamani
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Kirill S Golokhvast
- Siberian Federal Scientific Center of Agrobiotechnology RAS, Krasnoobsk, Russia, 630501
| | - Dimitrios P Bogdanos
- Department of Rheumatology and Clinical Immunology, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Aristidis Tsatsakis
- Center of Toxicology Science & Research, Medical School, University of Crete, 71003, Heraklion, Crete, Greece
| | - Vasileios Siokas
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Panayiotis D Mitsias
- Department of Neurology, School of Medicine, University of Crete, 71003, Heraklion, Greece; Department of Neurology, Henry Ford Hospital, Detroit, MI, USA
| | - Georgios M Hadjigeorgiou
- Department of Neurology, University Hospital of Larissa Greece, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece; Department of Neurology, Medical School, University of Cyprus, Nicosia, Cyprus
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4
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Barker SJ, Raju RM, Milman NEP, Wang J, Davila-Velderrain J, Gunter-Rahman F, Parro CC, Bozzelli PL, Abdurrob F, Abdelaal K, Bennett DA, Kellis M, Tsai LH. MEF2 is a key regulator of cognitive potential and confers resilience to neurodegeneration. Sci Transl Med 2021; 13:eabd7695. [PMID: 34731014 PMCID: PMC9258338 DOI: 10.1126/scitranslmed.abd7695] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Scarlett J Barker
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ravikiran M Raju
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Noah E P Milman
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jun Wang
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jose Davila-Velderrain
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Fatima Gunter-Rahman
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Cameron C Parro
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - P Lorenzo Bozzelli
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Fatema Abdurrob
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Karim Abdelaal
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Manolis Kellis
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Li-Huei Tsai
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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5
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Brenet A, Hassan-Abdi R, Somkhit J, Yanicostas C, Soussi-Yanicostas N. Defective Excitatory/Inhibitory Synaptic Balance and Increased Neuron Apoptosis in a Zebrafish Model of Dravet Syndrome. Cells 2019; 8:cells8101199. [PMID: 31590334 PMCID: PMC6829503 DOI: 10.3390/cells8101199] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/04/2019] [Accepted: 10/03/2019] [Indexed: 12/22/2022] Open
Abstract
Dravet syndrome is a type of severe childhood epilepsy that responds poorly to current anti-epileptic drugs. In recent years, zebrafish disease models with Scn1Lab sodium channel deficiency have been generated to seek novel anti-epileptic drug candidates, some of which are currently undergoing clinical trials. However, the spectrum of neuronal deficits observed following Scn1Lab depletion in zebrafish larvae has not yet been fully explored. To fill this gap and gain a better understanding of the mechanisms underlying neuron hyperexcitation in Scn1Lab-depleted larvae, we analyzed neuron activity in vivo using combined local field potential recording and transient calcium uptake imaging, studied the distribution of excitatory and inhibitory synapses and neurons as well as investigated neuron apoptosis. We found that Scn1Lab-depleted larvae displayed recurrent epileptiform seizure events, associating massive synchronous calcium uptakes and ictal-like local field potential bursts. Scn1Lab-depletion also caused a dramatic shift in the neuronal and synaptic balance toward excitation and increased neuronal death. Our results thus provide in vivo evidence suggesting that Scn1Lab loss of function causes neuron hyperexcitation as the result of disturbed synaptic balance and increased neuronal apoptosis.
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Affiliation(s)
- Alexandre Brenet
- Université de Paris, NeuroDiderot, Inserm, F-75019 Paris, France.
| | | | - Julie Somkhit
- Université de Paris, NeuroDiderot, Inserm, F-75019 Paris, France.
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6
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Iha HA, Kunisawa N, Shimizu S, Onishi M, Nomura Y, Matsubara N, Iwai C, Ogawa M, Hashimura M, Sato K, Kato M, Ohno Y. Mechanism Underlying Organophosphate Paraoxon-Induced Kinetic Tremor. Neurotox Res 2019; 35:575-583. [DOI: 10.1007/s12640-019-0007-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/22/2019] [Accepted: 01/28/2019] [Indexed: 12/18/2022]
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7
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Kunisawa N, Shimizu S, Kato M, Iha HA, Iwai C, Hashimura M, Ogawa M, Kawaji S, Kawakita K, Abe K, Ohno Y. Pharmacological characterization of nicotine-induced tremor: Responses to anti-tremor and anti-epileptic agents. J Pharmacol Sci 2018; 137:162-169. [PMID: 29945769 DOI: 10.1016/j.jphs.2018.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/18/2018] [Accepted: 05/23/2018] [Indexed: 12/19/2022] Open
Abstract
We previously showed that nicotine evoked kinetic tremor by activating the inferior olive, which is implicated in the pathogenesis of essential tremor, via α7 nicotinic acetylcholine receptors. Here, we evaluated the effects of various anti-tremor and anti-epileptic agents on nicotine-induced tremor in mice to clarify the pharmacological characteristics of nicotine tremor. Drugs effective for essential tremor, propranolol, diazepam and phenobarbital, all significantly inhibited kinetic tremor induced by an intraperitoneal (i.p.) injection of nicotine (1 mg/kg). In contrast, none of the medications for Parkinson's disease, l-DOPA, bromocriptine or trihexyphenidyl, affected the nicotine tremor. Among the anti-epileptic agents examined, valproate, carbamazepine and ethosuximide, significantly inhibited nicotine-induced tremor. In addition, a selective T-type Ca2+ channel blocker, TTA-A2, also suppressed the nicotine tremor. However, neither gabapentin, topiramate, zonisamide nor levetiracetam significantly affected nicotine-induced tremor. The present results show that nicotine-induced tremor resembles essential tremor not only on the neural basis, but also in terms of the pharmacological responses to anti-tremor agents, implying that nicotine-induced tremor can serve as a model for essential tremor. In addition, it is suggested that anti-epileptic agents, which have stimulant actions on the GABAergic system or blocking actions on voltage-gated Na+ channels and T-type Ca2+ channels, can alleviate essential tremor.
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Affiliation(s)
- Naofumi Kunisawa
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Saki Shimizu
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Masaki Kato
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Higor A Iha
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Chihiro Iwai
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Mai Hashimura
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Mizuki Ogawa
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Shohei Kawaji
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Kazuma Kawakita
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Keisuke Abe
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Yukihiro Ohno
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
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8
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Auvin S, Jeljeli M, Desnous B, Soussi-Yanicostas N, Dournaud P, Sterkers G. Altered vaccine-induced immunity in children with Dravet syndrome. Epilepsia 2018. [PMID: 29512885 DOI: 10.1111/epi.14038] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Dravet syndrome (DS) is a refractory epileptic syndrome. Vaccination is the trigger of the first seizure in about 50% of cases. Fever remains a trigger of seizures during the course of the disease. We compared ex vivo cytokine responses to a combined aluminium-adjuvanted vaccine of children with DS to sex- and age-matched heathy children. Using ex vivo cytokine responses of peripheral-blood mononuclear cells and monocytes, we found that vaccine responsiveness is biased toward a proinflammatory profile in DS with a M1 phenotype of monocytes. We provide new insight into immune mechanisms associated with DS that might guide research for the development of new immunotherapeutic agents in this epilepsy syndrome.
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Affiliation(s)
- Stéphane Auvin
- PROTECT, INSERM, Paris Diderot University, Sorbonne Paris Cité, Paris, France.,APHP, Pediatric Neurology Department, Robert-Debré University Hospital, Paris, France
| | - Mohamed Jeljeli
- APHP, Clinical Immunology Department, Robert-Debré University Hospital, Paris, France
| | - Béatrice Desnous
- PROTECT, INSERM, Paris Diderot University, Sorbonne Paris Cité, Paris, France.,APHP, Pediatric Neurology Department, Robert-Debré University Hospital, Paris, France
| | | | - Pascal Dournaud
- PROTECT, INSERM, Paris Diderot University, Sorbonne Paris Cité, Paris, France
| | - Ghislaine Sterkers
- APHP, Clinical Immunology Department, Robert-Debré University Hospital, Paris, France
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9
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Dutton SBB, Dutt K, Papale LA, Helmers S, Goldin AL, Escayg A. Early-life febrile seizures worsen adult phenotypes in Scn1a mutants. Exp Neurol 2017; 293:159-171. [PMID: 28373025 DOI: 10.1016/j.expneurol.2017.03.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 02/17/2017] [Accepted: 03/22/2017] [Indexed: 01/27/2023]
Abstract
Mutations in the voltage-gated sodium channel (VGSC) gene SCN1A, encoding the Nav1.1 channel, are responsible for a number of epilepsy disorders including genetic epilepsy with febrile seizures plus (GEFS+) and Dravet syndrome (DS). Patients with SCN1A mutations often experience prolonged early-life febrile seizures (FSs), raising the possibility that these events may influence epileptogenesis and lead to more severe adult phenotypes. To test this hypothesis, we subjected 21-23-day-old mice expressing the human SCN1A GEFS+ mutation R1648H to prolonged hyperthermia, and then examined seizure and behavioral phenotypes during adulthood. We found that early-life FSs resulted in lower latencies to induced seizures, increased severity of spontaneous seizures, hyperactivity, and impairments in social behavior and recognition memory during adulthood. Biophysical analysis of brain slice preparations revealed an increase in epileptiform activity in CA3 pyramidal neurons along with increased action potential firing, providing a mechanistic basis for the observed worsening of adult phenotypes. These findings demonstrate the long-term negative impact of early-life FSs on disease outcomes. This has important implications for the clinical management of this patient population and highlights the need for therapeutic interventions that could ameliorate disease progression.
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Affiliation(s)
- Stacey B B Dutton
- Department of Human Genetics, Emory University, Atlanta, GA 30022, USA; Department of Biology, Agnes Scott College, Atlanta, GA 30030, USA
| | - Karoni Dutt
- Departments of Microbiology & Molecular Genetics and Anatomy & Neurobiology, University of California, Irvine, CA 92697, USA
| | - Ligia A Papale
- Department of Human Genetics, Emory University, Atlanta, GA 30022, USA
| | - Sandra Helmers
- Department of Neurology, Emory University, Atlanta, GA 30022, USA
| | - Alan L Goldin
- Departments of Microbiology & Molecular Genetics and Anatomy & Neurobiology, University of California, Irvine, CA 92697, USA
| | - Andrew Escayg
- Department of Human Genetics, Emory University, Atlanta, GA 30022, USA.
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10
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Iha HA, Kunisawa N, Shimizu S, Tokudome K, Mukai T, Kinboshi M, Ikeda A, Ito H, Serikawa T, Ohno Y. Nicotine Elicits Convulsive Seizures by Activating Amygdalar Neurons. Front Pharmacol 2017; 8:57. [PMID: 28232801 PMCID: PMC5298991 DOI: 10.3389/fphar.2017.00057] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 01/26/2017] [Indexed: 12/14/2022] Open
Abstract
Nicotinic acetylcholine (nACh) receptors are implicated in the pathogenesis of epileptic disorders; however, the mechanisms of nACh receptors in seizure generation remain unknown. Here, we performed behavioral and immunohistochemical studies in mice and rats to clarify the mechanisms underlying nicotine-induced seizures. Treatment of animals with nicotine (1–4 mg/kg, i.p.) produced motor excitement in a dose-dependent manner and elicited convulsive seizures at 3 and 4 mg/kg. The nicotine-induced seizures were abolished by a subtype non-selective nACh antagonist, mecamylamine (MEC). An α7 nACh antagonist, methyllycaconitine, also significantly inhibited nicotine-induced seizures whereas an α4β2 nACh antagonist, dihydro-β-erythroidine, affected only weakly. Topographical analysis of Fos protein expression, a biological marker of neural excitation, revealed that a convulsive dose (4 mg/kg) of nicotine region-specifically activated neurons in the piriform cortex, amygdala, medial habenula, paratenial thalamus, anterior hypothalamus and solitary nucleus among 48 brain regions examined, and this was also suppressed by MEC. In addition, electric lesioning of the amygdala, but not the piriform cortex, medial habenula and thalamus, specifically inhibited nicotine-induced seizures. Furthermore, microinjection of nicotine (100 and 300 μg/side) into the amygdala elicited convulsive seizures in a dose-related manner. The present results suggest that nicotine elicits convulsive seizures by activating amygdalar neurons mainly via α7 nACh receptors.
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Affiliation(s)
- Higor A Iha
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Naofumi Kunisawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Saki Shimizu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Kentaro Tokudome
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Takahiro Mukai
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Masato Kinboshi
- Laboratory of Pharmacology, Osaka University of Pharmaceutical SciencesOsaka, Japan; Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto UniversityKyoto, Japan; Department of Neurology, Graduate School of Medicine, Wakayama Medical UniversityWakayama, Japan
| | - Akio Ikeda
- Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto University Kyoto, Japan
| | - Hidefumi Ito
- Department of Neurology, Graduate School of Medicine, Wakayama Medical University Wakayama, Japan
| | - Tadao Serikawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Yukihiro Ohno
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
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11
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Kunisawa N, Iha HA, Shimizu S, Tokudome K, Mukai T, Kinboshi M, Serikawa T, Ohno Y. Nicotine evokes kinetic tremor by activating the inferior olive via α7 nicotinic acetylcholine receptors. Behav Brain Res 2016; 314:173-80. [DOI: 10.1016/j.bbr.2016.08.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/02/2016] [Accepted: 08/06/2016] [Indexed: 10/21/2022]
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Tokudome K, Okumura T, Terada R, Shimizu S, Kunisawa N, Mashimo T, Serikawa T, Sasa M, Ohno Y. A Missense Mutation of the Gene Encoding Synaptic Vesicle Glycoprotein 2A (SV2A) Confers Seizure Susceptibility by Disrupting Amygdalar Synaptic GABA Release. Front Pharmacol 2016; 7:210. [PMID: 27471467 PMCID: PMC4943941 DOI: 10.3389/fphar.2016.00210] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 06/30/2016] [Indexed: 12/14/2022] Open
Abstract
Synaptic vesicle glycoprotein 2A (SV2A) is specifically expressed in the membranes of synaptic vesicles and modulates action potential-dependent neurotransmitter release. To explore the role of SV2A in the pathogenesis of epileptic disorders, we recently generated a novel rat model (Sv2aL174Q rat) carrying a missense mutation of the Sv2a gene and showed that the Sv2aL174Q rats were hypersensitive to kindling development (Tokudome et al., 2016). Here, we further conducted behavioral and neurochemical studies to clarify the pathophysiological mechanisms underlying the seizure vulnerability in Sv2aL174Q rats. Sv2aL174Q rats were highly susceptible to pentylenetetrazole (PTZ)-induced seizures, yielding a significantly higher seizure scores and seizure incidence than the control animals. Brain mapping analysis of Fos expression, a biological marker of neural excitation, revealed that the seizure threshold level of PTZ region-specifically elevated Fos expression in the amygdala in Sv2aL174Q rats. In vivo microdialysis study showed that the Sv2aL174Q mutation preferentially reduced high K+ (depolarization)-evoked GABA release, but not glutamate release, in the amygdala. In addition, specific control of GABA release by SV2A was supported by its predominant expression in GABAergic neurons, which were co-stained with antibodies against SV2A and glutamate decarboxylase 1. The present results suggest that dysfunction of SV2A by the missense mutation elevates seizure susceptibility in rats by preferentially disrupting synaptic GABA release in the amygdala, illustrating the crucial role of amygdalar SV2A-GABAergic system in epileptogenesis.
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Affiliation(s)
- Kentaro Tokudome
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Takahiro Okumura
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Ryo Terada
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Saki Shimizu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Naofumi Kunisawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Tomoji Mashimo
- Institute of Laboratory Animals, Graduate School of Medicine, Kyoto UniversityKyoto, Japan; Institute of Experimental Animal Sciences, Graduate School of Medicine, Osaka UniversityOsaka, Japan
| | - Tadao Serikawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical SciencesOsaka, Japan; Institute of Laboratory Animals, Graduate School of Medicine, Kyoto UniversityKyoto, Japan
| | | | - Yukihiro Ohno
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
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Synaptic vesicle glycoprotein 2A (SV2A) regulates kindling epileptogenesis via GABAergic neurotransmission. Sci Rep 2016; 6:27420. [PMID: 27265781 PMCID: PMC4893657 DOI: 10.1038/srep27420] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/18/2016] [Indexed: 02/08/2023] Open
Abstract
Synaptic vesicle glycoprotein 2A (SV2A) is a prototype synaptic vesicle protein regulating action potential-dependent neurotransmitters release. SV2A also serves as a specific binding site for certain antiepileptics and is implicated in the treatment of epilepsy. Here, to elucidate the role of SV2A in modulating epileptogenesis, we generated a novel rat model (Sv2aL174Q rat) carrying a Sv2a-targeted missense mutation (L174Q) and analyzed its susceptibilities to kindling development. Although animals homozygous for the Sv2aL174Q mutation exhibited normal appearance and development, they are susceptible to pentylenetetrazole (PTZ) seizures. In addition, development of kindling associated with repeated PTZ treatments or focal stimulation of the amygdala was markedly facilitated by the Sv2aL174Q mutation. Neurochemical studies revealed that the Sv2aL174Q mutation specifically reduced depolarization-induced GABA, but not glutamate, release in the hippocampus without affecting basal release or the SV2A expression level in GABAergic neurons. In addition, the Sv2aL174Q mutation selectively reduced the synaptotagmin1 (Syt1) level among the exocytosis-related proteins examined. The present results demonstrate that dysfunction of SV2A due to the Sv2aL174Q mutation impairs the synaptic GABA release by reducing the Syt1 level and facilitates the kindling development, illustrating the crucial role of SV2A-GABA system in modulating kindling epileptogenesis.
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Ohno Y, Shimizu S, Tatara A, Imaoku T, Ishii T, Sasa M, Serikawa T, Kuramoto T. Hcn1 is a tremorgenic genetic component in a rat model of essential tremor. PLoS One 2015; 10:e0123529. [PMID: 25970616 PMCID: PMC4430019 DOI: 10.1371/journal.pone.0123529] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 02/18/2015] [Indexed: 01/12/2023] Open
Abstract
Genetic factors are thought to play a major role in the etiology of essential tremor (ET); however, few genetic changes that induce ET have been identified to date. In the present study, to find genes responsible for the development of ET, we employed a rat model system consisting of a tremulous mutant strain, TRM/Kyo (TRM), and its substrain TRMR/Kyo (TRMR). The TRM rat is homozygous for the tremor (tm) mutation and shows spontaneous tremors resembling human ET. The TRMR rat also carries a homozygous tm mutation but shows no tremor, leading us to hypothesize that TRM rats carry one or more genes implicated in the development of ET in addition to the tm mutation. We used a positional cloning approach and found a missense mutation (c. 1061 C>T, p. A354V) in the hyperpolarization-activated cyclic nucleotide-gated 1 channel (Hcn1) gene. The A354V HCN1 failed to conduct hyperpolarization-activated currents in vitro, implicating it as a loss-of-function mutation. Blocking HCN1 channels with ZD7288 in vivo evoked kinetic tremors in nontremulous TRMR rats. We also found neuronal activation of the inferior olive (IO) in both ZD7288-treated TRMR and non-treated TRM rats and a reduced incidence of tremor in the IO-lesioned TRM rats, suggesting a critical role of the IO in tremorgenesis. A rat strain carrying the A354V mutation alone on a genetic background identical to that of the TRM rats showed no tremor. Together, these data indicate that body tremors emerge when the two mutant loci, tm and Hcn1A354V, are combined in a rat model of ET. In this model, HCN1 channels play an important role in the tremorgenesis of ET. We propose that oligogenic, most probably digenic, inheritance is responsible for the genetic heterogeneity of ET.
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Affiliation(s)
- Yukihiro Ohno
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, 569–1094, Japan
| | - Saki Shimizu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, 569–1094, Japan
| | - Ayaka Tatara
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, 569–1094, Japan
| | - Takuji Imaoku
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, 569–1094, Japan
| | - Takahiro Ishii
- Department of Physiology and Neurobiology, Graduate School of Medicine, Kyoto University, Kyoto, 606–8501, Japan
| | | | - Tadao Serikawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, 569–1094, Japan
- Institute of Laboratory Animals, Graduate School of Medicine, Kyoto University, Kyoto, 606–8501, Japan
| | - Takashi Kuramoto
- Institute of Laboratory Animals, Graduate School of Medicine, Kyoto University, Kyoto, 606–8501, Japan
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Functional and structural deficits of the dentate gyrus network coincide with emerging spontaneous seizures in an Scn1a mutant Dravet Syndrome model during development. Neurobiol Dis 2015; 77:35-48. [PMID: 25725421 DOI: 10.1016/j.nbd.2015.02.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 01/03/2015] [Accepted: 02/16/2015] [Indexed: 12/27/2022] Open
Abstract
Dravet syndrome (DS) is characterized by severe infant-onset myoclonic epilepsy along with delayed psychomotor development and heightened premature mortality. A primary monogenic cause is mutation of the SCN1A gene, which encodes the voltage-gated sodium channel subunit Nav1.1. The nature and timing of changes caused by SCN1A mutation in the hippocampal dentate gyrus (DG) network, a core area for gating major excitatory input to hippocampus and a classic epileptogenic zone, are not well known. In particularly, it is still not clear whether the developmental deficit of this epileptogenic neural network temporally matches with the progress of seizure development. Here, we investigated the emerging functional and structural deficits of the DG network in a novel mouse model (Scn1a(E1099X/+)) that mimics the genetic deficit of human DS. Scn1a(E1099X/+) (Het) mice, similarly to human DS patients, exhibited early spontaneous seizures and were more susceptible to hyperthermia-induced seizures starting at postnatal week (PW) 3, with seizures peaking at PW4. During the same period, the Het DG exhibited a greater reduction of Nav1.1-expressing GABAergic neurons compared to other hippocampal areas. Het DG GABAergic neurons showed altered action potential kinetics, reduced excitability, and generated fewer spontaneous inhibitory inputs into DG granule cells. The effect of reduced inhibitory input to DG granule cells was exacerbated by heightened spontaneous excitatory transmission and elevated excitatory release probability in these cells. In addition to electrophysiological deficit, we observed emerging morphological abnormalities of DG granule cells. Het granule cells exhibited progressively reduced dendritic arborization and excessive spines, which coincided with imbalanced network activity and the developmental onset of spontaneous seizures. Taken together, our results establish the existence of significant structural and functional developmental deficits of the DG network and the temporal correlation between emergence of these deficits and the onset of seizures in Het animals. Most importantly, our results uncover the developmental deficits of neural connectivity in Het mice. Such structural abnormalities likely further exacerbate network instability and compromise higher-order cognitive processing later in development, and thus highlight the multifaceted impacts of Scn1a deficiency on neural development.
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Serikawa T, Mashimo T, Kuramoro T, Voigt B, Ohno Y, Sasa M. Advances on genetic rat models of epilepsy. Exp Anim 2014; 64:1-7. [PMID: 25312505 PMCID: PMC4329510 DOI: 10.1538/expanim.14-0066] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Considering the suitability of laboratory rats in epilepsy research, we and other groups
have been developing genetic models of epilepsy in this species. After epileptic rats or
seizure-susceptible rats were sporadically found in outbred stocks, the epileptic traits
were usually genetically-fixed by selective breeding. So far, the absence seizure models
GAERS and WAG/Rij, audiogenic seizure models GEPR-3 and GEPR-9, generalized tonic-clonic
seizure models IER, NER and WER, and Canavan-disease related epileptic models TRM and SER
have been established. Dissection of the genetic bases including causative genes in these
epileptic rat models would be a significant step toward understanding epileptogenesis.
N-ethyl-N-nitrosourea (ENU) mutagenesis provides a systematic approach which allowed us to
develop two novel epileptic rat models: heat-induced seizure susceptible (Hiss) rats with
an Scn1a missense mutation and autosomal dominant lateral temporal epilepsy (ADLTE) model
rats with an Lgi1 missense mutation. In addition, we have established episodic ataxia type
1 (EA1) model rats with a Kcna1 missense mutation derived from the ENU-induced rat mutant
stock, and identified a Cacna1a missense mutation in a N-Methyl-N-nitrosourea
(MNU)-induced mutant rat strain GRY, resulting in the discovery of episodic ataxia type 2
(EA2) model rats. Thus, epileptic rat models have been established on the two paths:
‘phenotype to gene’ and ‘gene to phenotype’. In the near future, development of novel
epileptic rat models will be extensively promoted by the use of sophisticated genome
editing technologies.
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Affiliation(s)
- Tadao Serikawa
- Graduate School of Medicine, Kyoto University, Sakyo-ku 606-8501; Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki 569-1094, Japan
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Expressional Analysis of Inwardly Rectifying Kir4.1 Channels in Groggy Rats, a Rat Model of Absence Seizures. ARCHIVES OF NEUROSCIENCE 2014. [DOI: 10.5812/archneurosci.18651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Preferential suppression of limbic Fos expression by intermittent hypoxia in obese diabetic mice. Neurosci Res 2013; 77:202-7. [DOI: 10.1016/j.neures.2013.09.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 09/18/2013] [Accepted: 09/30/2013] [Indexed: 12/20/2022]
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Harada Y, Nagao Y, Shimizu S, Serikawa T, Terada R, Fujimoto M, Okuda A, Mukai T, Sasa M, Kurachi Y, Ohno Y. Expressional analysis of inwardly rectifying Kir4.1 channels in Noda epileptic rat (NER). Brain Res 2013; 1517:141-9. [PMID: 23603404 DOI: 10.1016/j.brainres.2013.04.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 03/31/2013] [Accepted: 04/09/2013] [Indexed: 11/30/2022]
Abstract
The inwardly rectifying potassium channel subunit Kir4.1 is expressed in brain astrocytes and involved in spatial K(+) buffering, regulating neural activity. To explore the pathophysiological alterations of Kir4.1 channels in epileptic disorders, we analyzed interictal expressional levels of Kir4.1 in the Noda epileptic rat (NER), a hereditary animal model for generalized tonic-clonic (GTC) seizures. Western blot analysis showed that Kir4.1 expression in NERs was significantly reduced in the occipito-temporal cortical region and thalamus. However, the expression of Kir5.1, another Kir subunit mediating spatial K(+) buffering, remained unaltered in any brain regions examined. Immunohistochemical analysis revealed that Kir4.1 was primarily expressed in glial fibrillary acidic protein (GFAP)-positive astrocytes (somata) and foot processes clustered around neurons proved with anti-neuronal nuclear antigen (NeuN) antibody. In NERs, Kir4.1 expression in astrocytic processes was region-selectively diminished in the amygdaloid nuclei (i.e., medial amygdaloid nucleus and basomedial amygdaloid nucleus) while Kir4.1 expression in astrocytic somata was unchanged. Furthermore, the amygdala regions with reduced Kir4.1 expression showed a marked elevation of Fos protein expression following GTC seizures. The present results suggest that reduced activity of astrocytic Kir4.1 channels in the amygdala is involved in limbic hyperexcitability in NERs.
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Affiliation(s)
- Yuya Harada
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, Takatsuki, Osaka 569-1094, Japan
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Neuronal injury and cytogenesis after simple febrile seizures in the hippocampal dentate gyrus of juvenile rat. Childs Nerv Syst 2012; 28:1931-6. [PMID: 22661146 DOI: 10.1007/s00381-012-1817-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 05/18/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE Although simple febrile seizures are frequently described as harmless, there is evidence which suggests that hippocampal damage may occur after simple febrile seizures. This study aimed to investigate possible neuronal damages as well as alterations in cytogenesis in the hippocampal dentate gyrus following simple febrile seizures. METHODS Simple febrile seizure was modeled by hyperthermia-induced seizures in 22-day-old male rats. The brains were removed 2 or 15 days after hyperthermia in all rats with (n=20) and without (n=10) occurrence of seizures as well as in control animals (n=10). The sections were stained with hematoxylin and eosin to estimate the surface numerical density of dark neurons. Ki-67 immunohistochemistry was performed to evaluate changes of cytogenesis following simple febrile seizures. RESULTS Hyperthermia induced behavioral seizure activities in 67 % of the rats. The numerical densities of dark neurons as well as the mean Ki-67 index (the fraction of Ki-67-positive cells) were significantly increased in dentate gyrus after induction of seizures by hyperthermia compared to both controls and rats without seizure after hyperthermia. Both the seizure duration and intensity were correlated significantly with numerical densities of dark neurons (but not with Ki-67 index). CONCLUSION The data indicate that simple febrile seizures can cause neuronal damages and enhancement of cytogenesis in the hippocampal dentate gyrus, which were still visible for at least 2 weeks. These findings also suggest the correlation of febrile seizure intensity and duration with neuronal damage.
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Ohno Y, Okano M, Masui A, Imaki J, Egawa M, Yoshihara C, Tatara A, Mizuguchi Y, Sasa M, Shimizu S. Region-specific elevation of D1 receptor-mediated neurotransmission in the nucleus accumbens of SHR, a rat model of attention deficit/hyperactivity disorder. Neuropharmacology 2012; 63:547-54. [DOI: 10.1016/j.neuropharm.2012.04.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 04/21/2012] [Accepted: 04/28/2012] [Indexed: 11/16/2022]
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Ohno Y, Okumura T, Terada R, Ishihara S, Serikawa T, Sasa M. Kindling-associated SV2A expression in hilar GABAergic interneurons of the mouse dentate gyrus. Neurosci Lett 2012; 510:93-8. [DOI: 10.1016/j.neulet.2012.01.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 12/25/2011] [Accepted: 01/04/2012] [Indexed: 01/14/2023]
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Desnous B, Goujon E, Bellavoine V, Merdariu D, Auvin S. Perceptions of fever and fever management practices in parents of children with Dravet syndrome. Epilepsy Behav 2011; 21:446-8. [PMID: 21703932 DOI: 10.1016/j.yebeh.2011.05.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Revised: 04/01/2011] [Accepted: 05/06/2011] [Indexed: 12/01/2022]
Abstract
OBJECTIVE The first seizure in Dravet syndrome is often considered a febrile seizure (FS), but shortly thereafter, both FSs and seizures without fever occur, leading to diagnosis. Fever remains a factor that easily precipitates seizures. We studied the perception and management of fever of parents of children with Dravet syndrome. METHODS We conducted this survey using an anonymous, self-administered questionnaire. RESULTS A total of 20 parents returned the questionnaire. Fever remains a trigger of seizures in 90% of patients. All parents have an accurate knowledge of fever and its management. The familial and socioprofessional impact of fever attacks appears to be very strong. CONCLUSION Fever represents a significant concern of parents of children with Dravet syndrome. The level of parental anxiety is high in case of fever. The anxiety seems related to fear of seizure recurrence leading to significant modification of parental behavior.
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