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Yuan Y, Lopez-Santiago L, Denomme N, Chen C, O'Malley HA, Hodges SL, Ji S, Han Z, Christiansen A, Isom LL. Antisense oligonucleotides restore excitability, GABA signalling and sodium current density in a Dravet syndrome model. Brain 2024; 147:1231-1246. [PMID: 37812817 PMCID: PMC10994531 DOI: 10.1093/brain/awad349] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 09/13/2023] [Accepted: 09/27/2023] [Indexed: 10/11/2023] Open
Abstract
Dravet syndrome is an intractable developmental and epileptic encephalopathy caused by de novo variants in SCN1A resulting in haploinsufficiency of the voltage-gated sodium channel Nav1.1. We showed previously that administration of the antisense oligonucleotide STK-001, also called ASO-22, generated using targeted augmentation of nuclear gene output technology to prevent inclusion of the nonsense-mediated decay, or poison, exon 20N in human SCN1A, increased productive Scn1a transcript and Nav1.1 expression and reduced the incidence of electrographic seizures and sudden unexpected death in epilepsy in a mouse model of Dravet syndrome. Here, we investigated the mechanism of action of ASO-84, a surrogate for ASO-22 that also targets splicing of SCN1A exon 20N, in Scn1a+/- Dravet syndrome mouse brain. Scn1a +/- Dravet syndrome and wild-type mice received a single intracerebroventricular injection of antisense oligonucleotide or vehicle at postnatal Day 2. We examined the electrophysiological properties of cortical pyramidal neurons and parvalbumin-positive fast-spiking interneurons in brain slices at postnatal Days 21-25 and measured sodium currents in parvalbumin-positive interneurons acutely dissociated from postnatal Day 21-25 brain slices. We show that, in untreated Dravet syndrome mice, intrinsic cortical pyramidal neuron excitability was unchanged while cortical parvalbumin-positive interneurons showed biphasic excitability with initial hyperexcitability followed by hypoexcitability and depolarization block. Dravet syndrome parvalbumin-positive interneuron sodium current density was decreased compared to wild-type. GABAergic signalling to cortical pyramidal neurons was reduced in Dravet syndrome mice, suggesting decreased GABA release from interneurons. ASO-84 treatment restored action potential firing, sodium current density and GABAergic signalling in Dravet syndrome parvalbumin-positive interneurons. Our work suggests that interneuron excitability is selectively affected by ASO-84. This new work provides critical insights into the mechanism of action of this antisense oligonucleotide and supports the potential of antisense oligonucleotide-mediated upregulation of Nav1.1 as a successful strategy to treat Dravet syndrome.
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Affiliation(s)
- Yukun Yuan
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Luis Lopez-Santiago
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicholas Denomme
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Chunling Chen
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Heather A O'Malley
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Samantha L Hodges
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sophina Ji
- Stoke Therapeutics, Inc., Bedford, MA 01730, USA
| | - Zhou Han
- Stoke Therapeutics, Inc., Bedford, MA 01730, USA
| | | | - Lori L Isom
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
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Proietti J, Fiorini E, Cantalupo G, Fontana E, Lo Barco T, Bonin C, Bernardina BD, Darra F. Refractory tonic-myoclonic status epilepticus with catamenial recurrence in epilepsy with myoclonic atonic seizures: A case report. Heliyon 2024; 10:e24747. [PMID: 38304836 PMCID: PMC10831770 DOI: 10.1016/j.heliyon.2024.e24747] [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: 09/19/2023] [Revised: 12/08/2023] [Accepted: 01/12/2024] [Indexed: 02/03/2024] Open
Abstract
In epilepsy with myoclonic-atonic seizures (EMA), status epilepticus (SE) may occur during the onset phase, uncommonly in post-puberal patients. We report a post-puberal patient with EMA who presented SE with insidious onset and catamenial recurrence. She had a stormy epilepsy onset at 4 years, with tonic seizures, atypical absences, and myoclonic-atonic seizures, in the absence of SE. After the onset phase, sporadic nocturnal tonic seizures persisted and a mild intellectual disability appeared. At the age of 7, after gonadotropin-releasing hormone analog administration due to central precocious puberty, she presented with SE characterized by recurrent atypical absences, tonic seizures, and awareness impairment, which was successfully treated in 4 days. At 11 years, one week before menstruation, the patient presented with analogous SE that lasted 8 days. One week before the subsequent menstruation, she presented again with SE, initially characterized by atypical absences alternating with phases of awareness and motor impairment related to fast low-voltage EEG activity in the central regions; later, tonic and myoclonic seizures occurring even in the awake state increased, and the "atonic-akinetic status" related to fast EEG activity worsened. After conventional antiepileptic drugs had failed to control the seizures, a progestin was added, with subsequent gradual complete recovery.
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Affiliation(s)
- Jacopo Proietti
- UOC Neuropsichiatria Infantile, Dipartimento Materno-Infantile, Azienda Ospedaliero-Universitaria Integrata, Verona, Italy - Full member of ERN EpiCARE
- Innovation biomedicine Section, Department of Engineering for Innovation Medicine, University of Verona, Verona, Italy
- Center for Research on Epilepsies in Pediatric age (CREP), Verona, Italy
| | - Elena Fiorini
- UOC Neuropsichiatria Infantile, Dipartimento Materno-Infantile, Azienda Ospedaliero-Universitaria Integrata, Verona, Italy - Full member of ERN EpiCARE
- Center for Research on Epilepsies in Pediatric age (CREP), Verona, Italy
| | - Gaetano Cantalupo
- UOC Neuropsichiatria Infantile, Dipartimento Materno-Infantile, Azienda Ospedaliero-Universitaria Integrata, Verona, Italy - Full member of ERN EpiCARE
- Innovation biomedicine Section, Department of Engineering for Innovation Medicine, University of Verona, Verona, Italy
- Center for Research on Epilepsies in Pediatric age (CREP), Verona, Italy
| | - Elena Fontana
- UOC Neuropsichiatria Infantile, Dipartimento Materno-Infantile, Azienda Ospedaliero-Universitaria Integrata, Verona, Italy - Full member of ERN EpiCARE
- Center for Research on Epilepsies in Pediatric age (CREP), Verona, Italy
| | - Tommaso Lo Barco
- UOC Neuropsichiatria Infantile, Dipartimento Materno-Infantile, Azienda Ospedaliero-Universitaria Integrata, Verona, Italy - Full member of ERN EpiCARE
- Center for Research on Epilepsies in Pediatric age (CREP), Verona, Italy
| | - Cecilia Bonin
- U.O.C. Ostetricia e Ginecologia B, Dipartimento di Ostetricia e Ginecologia, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | | | - Francesca Darra
- UOC Neuropsichiatria Infantile, Dipartimento Materno-Infantile, Azienda Ospedaliero-Universitaria Integrata, Verona, Italy - Full member of ERN EpiCARE
- Innovation biomedicine Section, Department of Engineering for Innovation Medicine, University of Verona, Verona, Italy
- Center for Research on Epilepsies in Pediatric age (CREP), Verona, Italy
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3
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Chen C, Ziobro J, Robinson-Cooper L, Hodges SL, Chen Y, Edokobi N, Lopez-Santiago L, Habig K, Moore C, Minton J, Bramson S, Scheuing C, Daddo N, Štěrbová K, Weckhuysen S, Parent JM, Isom LL. Epilepsy and sudden unexpected death in epilepsy in a mouse model of human SCN1B-linked developmental and epileptic encephalopathy. Brain Commun 2023; 5:fcad283. [PMID: 38425576 PMCID: PMC10903178 DOI: 10.1093/braincomms/fcad283] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 07/13/2023] [Accepted: 10/18/2023] [Indexed: 03/02/2024] Open
Abstract
Voltage-gated sodium channel β1 subunits are essential proteins that regulate excitability. They modulate sodium and potassium currents, function as cell adhesion molecules and regulate gene transcription following regulated intramembrane proteolysis. Biallelic pathogenic variants in SCN1B, encoding β1, are linked to developmental and epileptic encephalopathy 52, with clinical features overlapping Dravet syndrome. A recessive variant, SCN1B-c.265C>T, predicting SCN1B-p.R89C, was homozygous in two children of a non-consanguineous family. One child was diagnosed with Dravet syndrome, while the other had a milder phenotype. We identified an unrelated biallelic SCN1B-c.265C>T patient with a clinically more severe phenotype than Dravet syndrome. We used CRISPR/Cas9 to knock-in SCN1B-p.R89C to the mouse Scn1b locus (Scn1bR89/C89). We then rederived the line on the C57BL/6J background to allow comparisons between Scn1bR89/R89 and Scn1bC89/C89 littermates with Scn1b+/+ and Scn1b-/- mice, which are congenic on C57BL/6J, to determine whether the SCN1B-c.265C>T variant results in loss-of-function. Scn1bC89/C89 mice have normal body weights and ∼20% premature mortality, compared with severely reduced body weight and 100% mortality in Scn1b-/- mice. β1-p.R89C polypeptides are expressed in brain at comparable levels to wild type. In heterologous cells, β1-p.R89C localizes to the plasma membrane and undergoes regulated intramembrane proteolysis similar to wild type. Heterologous expression of β1-p.R89C results in sodium channel α subunit subtype specific effects on sodium current. mRNA abundance of Scn2a, Scn3a, Scn5a and Scn1b was increased in Scn1bC89/C89 somatosensory cortex, with no changes in Scn1a. In contrast, Scn1b-/- mouse somatosensory cortex is haploinsufficient for Scn1a, suggesting an additive mechanism for the severity of the null model via disrupted regulation of another Dravet syndrome gene. Scn1bC89/C89 mice are more susceptible to hyperthermia-induced seizures at post-natal Day 15 compared with Scn1bR89/R89 littermates. EEG recordings detected epileptic discharges in young adult Scn1bC89/C89 mice that coincided with convulsive seizures and myoclonic jerks. We compared seizure frequency and duration in a subset of adult Scn1bC89/C89 mice that had been exposed to hyperthermia at post-natal Day 15 versus a subset that were not hyperthermia exposed. No differences in spontaneous seizures were detected between groups. For both groups, the spontaneous seizure pattern was diurnal, occurring with higher frequency during the dark cycle. This work suggests that the SCN1B-c.265C>T variant does not result in complete loss-of-function. Scn1bC89/C89 mice more accurately model SCN1B-linked variants with incomplete loss-of-function compared with Scn1b-/- mice, which model complete loss-of-function, and thus add to our understanding of disease mechanisms as well as our ability to develop new therapeutic strategies.
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Affiliation(s)
- Chunling Chen
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Julie Ziobro
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | | | - Samantha L Hodges
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Yan Chen
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Nnamdi Edokobi
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Luis Lopez-Santiago
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Karl Habig
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Chloe Moore
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Joe Minton
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Sabrina Bramson
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Caroline Scheuing
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Noor Daddo
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Katalin Štěrbová
- Department of Pediatric Neurology, Charles University and Motol Hospital, V Úvalu 84, 150 06 Prague 5, Czech Republic
| | - Sarah Weckhuysen
- Applied & Translational Neurogenomics Group, VIB Center for Molecular Neurology, VIB, Universiteitsplein 1 B-2610 Antwerpen, Belgium
- Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Universiteitsplein 1 B-2610 Antwerpen, Belgium
- Department of Neurology, Antwerp University Hospital, Universiteitsplein 1B-2610 Antwerpen, Belgium
- µNEURO Research Centre of Excellence, University of Antwerp, Universiteitsplein 1B-2610 Antwerpen, Belgium
| | - Jack M Parent
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Michigan Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Neurology, VA Ann Arbor Healthcare System, Ann Arbor, MI 48105, USA
| | - Lori L Isom
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Zhao H, Li S, He L, Tang F, Han X, Deng W, Lin Z, Huang R, Li Z. Ameliorating Effect of Umbilical Cord Mesenchymal Stem Cells in a Human Induced Pluripotent Stem Cell Model of Dravet Syndrome. Mol Neurobiol 2021; 59:748-761. [PMID: 34766239 DOI: 10.1007/s12035-021-02633-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 11/02/2021] [Indexed: 01/01/2023]
Abstract
Dravet syndrome (DS) is a form of severe childhood-onset refractory epilepsy typically caused by a heterozygous loss-of-function mutation. DS patient-derived induced pluripotent stem cells (iPSCs) are appropriate human cells for exploring disease mechanisms and testing new therapeutic strategies in vitro. Repeated spontaneous seizures can cause neuroinflammatory reactions and oxidative stress, resulting in neuronal toxicity, neuronal dysfunction, blood-brain barrier disruption, and hippocampal inflammation. Antiepileptic drug therapy does not delay the development of chronic epilepsy. The application of mesenchymal stem cells (MSCs) is one therapeutic strategy for thwarting epilepsy development. This study evaluated the effects of human umbilical cord mesenchymal stem cell-conditioned medium (HUMSC-CM) in a new in vitro model of neurons differentiated from DS patient-derived iPSCs. In the presence of HUMSC-CM, increases in superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2), glutathione peroxidase (GPX), and glutathione (GSH) levels were found to contribute to a reduction in reactive oxygen species (ROS) levels. In parallel, inflammation was rescued in DS patient-derived neuronal cells via increased expression of anti-inflammatory cytokines (TGF-β, IL-6, and IL-10) and significant downregulation of tumor necrosis factor-α and interleukin-1β expression. The intracellular calcium concentration ([Ca2+]i) and malondialdehyde (MDA) and ROS levels were decreased in DS patient-derived cells. In addition, action potential (AP) firing ability was enhanced by HUMSC-CM. In conclusion, HUMSC-CM can effectively eliminate ROS, affect migration and neurogenesis, and promote neurons to enter a highly functional state. Therefore, HUMSC-CM is a promising therapeutic strategy for the clinical treatment of refractory epilepsy such as DS.
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Affiliation(s)
- Huifang Zhao
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Shuai Li
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lang He
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Feng Tang
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaobo Han
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
- Guangzhou Medical University, Guangzhou, 511436, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Weiyue Deng
- Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Zuoxian Lin
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Rongqi Huang
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Zhiyuan Li
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China.
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, 510005, China.
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
- Guangzhou Medical University, Guangzhou, 511436, China.
- Department of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
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Han Z, Chen C, Christiansen A, Ji S, Lin Q, Anumonwo C, Liu C, Leiser SC, Meena, Aznarez I, Liau G, Isom LL. Antisense oligonucleotides increase Scn1a expression and reduce seizures and SUDEP incidence in a mouse model of Dravet syndrome. Sci Transl Med 2021; 12:12/558/eaaz6100. [PMID: 32848094 DOI: 10.1126/scitranslmed.aaz6100] [Citation(s) in RCA: 163] [Impact Index Per Article: 54.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 03/27/2020] [Accepted: 06/03/2020] [Indexed: 12/31/2022]
Abstract
Dravet syndrome (DS) is an intractable developmental and epileptic encephalopathy caused largely by de novo variants in the SCN1A gene, resulting in haploinsufficiency of the voltage-gated sodium channel α subunit NaV1.1. Here, we used Targeted Augmentation of Nuclear Gene Output (TANGO) technology, which modulates naturally occurring, nonproductive splicing events to increase target gene and protein expression and ameliorate disease phenotype in a mouse model. We identified antisense oligonucleotides (ASOs) that specifically increase the expression of productive Scn1a transcript in human cell lines, as well as in mouse brain. We show that a single intracerebroventricular dose of a lead ASO at postnatal day 2 or 14 reduced the incidence of electrographic seizures and sudden unexpected death in epilepsy (SUDEP) in the F1:129S-Scn1a +/- × C57BL/6J mouse model of DS. Increased expression of productive Scn1a transcript and NaV1.1 protein was confirmed in brains of treated mice. Our results suggest that TANGO may provide a unique, gene-specific approach for the treatment of DS.
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Affiliation(s)
- Zhou Han
- Stoke Therapeutics Inc., Bedford, MA 01730, USA
| | - Chunling Chen
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Sophina Ji
- Stoke Therapeutics Inc., Bedford, MA 01730, USA
| | - Qian Lin
- Stoke Therapeutics Inc., Bedford, MA 01730, USA
| | - Charles Anumonwo
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Chante Liu
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Meena
- Stoke Therapeutics Inc., Bedford, MA 01730, USA
| | | | - Gene Liau
- Stoke Therapeutics Inc., Bedford, MA 01730, USA
| | - Lori L Isom
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA.
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Morris G, Reschke CR, Henshall DC. Targeting microRNA-134 for seizure control and disease modification in epilepsy. EBioMedicine 2019; 45:646-654. [PMID: 31300345 PMCID: PMC6642437 DOI: 10.1016/j.ebiom.2019.07.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/03/2019] [Accepted: 07/03/2019] [Indexed: 02/06/2023] Open
Abstract
MicroRNA-134 is a brain-enriched small noncoding RNA that has been implicated in diverse neuronal functions, including regulating network excitability. Increased expression of microRNA-134 has been reported in several experimental epilepsy models and in resected brain tissue from temporal lobe epilepsy patients. Rodent studies have demonstrated that reducing microRNA-134 expression in the brain using antisense oligonucleotides can increase seizure thresholds and attenuate status epilepticus. Critically, inhibition of microRNA-134 after status epilepticus can potently reduce the occurrence of spontaneous recurrent seizures. Altered plasma levels of microRNA-134 have been reported in epilepsy patients, suggesting microRNA-134 may have diagnostic value as a biomarker. This review summarises findings on the cellular functions of microRNA-134, as well as the preclinical evidence supporting anti-seizure and disease-modifying effects of targeting microRNA-134 in epilepsy. Finally, we draw attention to unanswered questions and some of the challenges and opportunities involved in preclinical development of a microRNA-based oligonucleotide treatment for epilepsy.
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Affiliation(s)
- Gareth Morris
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland; FutureNeuro Research Centre, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Cristina R Reschke
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland; FutureNeuro Research Centre, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - David C Henshall
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland; FutureNeuro Research Centre, Royal College of Surgeons in Ireland, Dublin, Ireland.
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Abstract
Selective Nav1.1 Activation Rescues Dravet Syndrome Mice From Seizures and Premature Death Richards KL, Milligan CJ, Richardson RJ, Jancovski N, Grunnet M, Jacobson LH, Undheim EAB, Mobli M, Chow CY, Herzig V, Csoti A, Panyi G, Reid CA, King GF, Petrou S. PNAS. 2018;115:E8077-E8085. Dravet syndrome is a catastrophic, pharmaco-resistant epileptic encephalopathy. Disease onset occurs in the first year of life, followed by developmental delay with cognitive and behavioral dysfunction and substantially elevated risk of premature death. The majority of affected individuals harbor a loss-of-function mutation in one allele of SCN1A, which encodes the voltage-gated sodium channel Nav1.1. Brain Nav1.1 is primarily localized to fast-spiking inhibitory interneurons; thus, the mechanism of epileptogenesis in Dravet syndrome is hypothesized to be reduced inhibitory neurotransmission leading to brain hyperexcitability. We show that selective activation of Nav1.1 by venom peptide Hm1a restores the function of inhibitory interneurons from Dravet syndrome mice without affecting the firing of excitatory neurons. Intracerebroventricular infusion of Hm1a rescues Dravet syndrome mice from seizures and premature death. This precision medicine approach, which specifically targets the molecular deficit in Dravet syndrome, presents an opportunity for treatment of this intractable epilepsy. A Transient Developmental Window of Fast-Spiking Interneuron Dysfunction in a Mouse Model of Dravet Syndrome Favero M, Sotuyo NP, Lopez E, Kearney JA, Goldberg EM. J Neurosci. 2018;38:7912-7927. Dravet syndrome is a severe childhood-onset epilepsy largely due to heterozygous loss-of-function mutation of the gene SCN1A, which encodes the type 1 neuronal voltage-gated sodium (Na+) channel α subunit Nav1.1. Prior studies in mouse models of Dravet syndrome ( Scn1a+/- mice) indicate that, in cerebral cortex, Nav1.1 is predominantly expressed in GABAergic interneurons, in particular in parvalbumin-positive fast-spiking basket cell interneurons (PVINs). This has led to a model of Dravet syndrome pathogenesis in which Nav1.1 mutation leads to preferential dysfunction of interneurons, decreased synaptic inhibition, hyperexcitability, and epilepsy. However, such studies have been implemented at early developmental time points. Here, we performed electrophysiological recordings in acute brain slices prepared from male and female Scn1a+/-mice as well as age-matched wild-type littermate controls and found that, later in development, the excitability of PVINs had normalized. Analysis of action potential waveforms indirectly suggests a reorganization of axonal Na+ channels in PVINs from Scn1a+/- mice, a finding supported by immunohistochemical data showing elongation of the axon initial segment. Our results imply that transient impairment of action potential generation by PVINs may contribute to the initial appearance of epilepsy, but is not the mechanism of ongoing, chronic epilepsy in Dravet syndrome. Significance Statement: Dravet syndrome is characterized by normal early development, temperature-sensitive seizures in infancy, progression to treatment-resistant epilepsy, developmental delay, autism, and sudden unexplained death due to mutation in SCN1A encoding the Na+ channel subunit Nav1.1. Prior work has revealed a preferential impact of Nav1.1 loss on the function of GABAergic inhibitory interneurons. However, such data derive exclusively from recordings of neurons in young Scn1a+/- mice. Here, we show that impaired action potential generation observed in parvalbumin-positive fast-spiking interneurons (PVINs) in Scn1a+/- mice during early development has normalized by postnatal day 35. This work suggests that a transient impairment of PVINs contributes to epilepsy onset, but is not the mechanism of ongoing, chronic epilepsy in Dravet syndrome.
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Johannesen KM, Gardella E, Linnankivi T, Courage C, de Saint Martin A, Lehesjoki AE, Mignot C, Afenjar A, Lesca G, Abi-Warde MT, Chelly J, Piton A, Merritt JL, Rodan LH, Tan WH, Bird LM, Nespeca M, Gleeson JG, Yoo Y, Choi M, Chae JH, Czapansky-Beilman D, Reichert SC, Pendziwiat M, Verhoeven JS, Schelhaas HJ, Devinsky O, Christensen J, Specchio N, Trivisano M, Weber YG, Nava C, Keren B, Doummar D, Schaefer E, Hopkins S, Dubbs H, Shaw JE, Pisani L, Myers CT, Tang S, Tang S, Pal DK, Millichap JJ, Carvill GL, Helbig KL, Mecarelli O, Striano P, Helbig I, Rubboli G, Mefford HC, Møller RS. Defining the phenotypic spectrum of SLC6A1 mutations. Epilepsia 2018; 59:389-402. [PMID: 29315614 DOI: 10.1111/epi.13986] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2017] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Pathogenic SLC6A1 variants were recently described in patients with myoclonic atonic epilepsy (MAE) and intellectual disability (ID). We set out to define the phenotypic spectrum in a larger cohort of SCL6A1-mutated patients. METHODS We collected 24 SLC6A1 probands and 6 affected family members. Four previously published cases were included for further electroclinical description. In total, we reviewed the electroclinical data of 34 subjects. RESULTS Cognitive development was impaired in 33/34 (97%) subjects; 28/34 had mild to moderate ID, with language impairment being the most common feature. Epilepsy was diagnosed in 31/34 cases with mean onset at 3.7 years. Cognitive assessment before epilepsy onset was available in 24/31 subjects and was normal in 25% (6/24), and consistent with mild ID in 46% (11/24) or moderate ID in 17% (4/24). Two patients had speech delay only, and 1 had severe ID. After epilepsy onset, cognition deteriorated in 46% (11/24) of cases. The most common seizure types were absence, myoclonic, and atonic seizures. Sixteen cases fulfilled the diagnostic criteria for MAE. Seven further patients had different forms of generalized epilepsy and 2 had focal epilepsy. Twenty of 31 patients became seizure-free, with valproic acid being the most effective drug. There was no clear-cut correlation between seizure control and cognitive outcome. Electroencephalography (EEG) findings were available in 27/31 patients showing irregular bursts of diffuse 2.5-3.5 Hz spikes/polyspikes-and-slow waves in 25/31. Two patients developed an EEG pattern resembling electrical status epilepticus during sleep. Ataxia was observed in 7/34 cases. We describe 7 truncating and 18 missense variants, including 4 recurrent variants (Gly232Val, Ala288Val, Val342Met, and Gly362Arg). SIGNIFICANCE Most patients carrying pathogenic SLC6A1 variants have an MAE phenotype with language delay and mild/moderate ID before epilepsy onset. However, ID alone or associated with focal epilepsy can also be observed.
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Affiliation(s)
- Katrine M Johannesen
- The Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,Institute for Regional Health Services Research, University of Southern Denmark, Odense, Denmark
| | - Elena Gardella
- The Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,Institute for Regional Health Services Research, University of Southern Denmark, Odense, Denmark
| | - Tarja Linnankivi
- Department of Child Neurology, Children's Hospital, Helsinki University Hospital Helsinki, University of Helsinki, Helsinki, Finland
| | - Carolina Courage
- The Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland.,Research Programs Unit, Molecular Neurology and Neuroscience Center, Helsinki, Finland
| | - Anne de Saint Martin
- Department of Pediatrics, Pediatric Neurology, University Hospital of Strasbourg, Strasbourg, France.,Reference Center for Rare Epilepsies, Strasbourg, France
| | - Anna-Elina Lehesjoki
- The Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland.,Research Programs Unit, Molecular Neurology and Neuroscience Center, Helsinki, Finland
| | - Cyril Mignot
- Department of Genetics, Center for Rare causes of Intellectual Disabilities and UPMC Research Group "Intellectual Disabilities and Autism", Paris, France
| | | | - Gaetan Lesca
- Departments of Genetics, Lyon University Hospitals, Lyon, France.,Claude Bernard Lyon I University, Lyon, France.,Lyon Neuroscience Research Center, CNRS UMRS5292, INSERM U1028, Lyon, France
| | - Marie-Thérèse Abi-Warde
- Department of Pediatrics, Pediatric Neurology, University Hospital of Strasbourg, Strasbourg, France.,Reference Center for Rare Epilepsies, Strasbourg, France
| | - Jamel Chelly
- Department of Translational Medicine and Neurogenetics, Institut Génétique Biologie Moléculaire Cellulaire (IGBMC), Illkirch, France.,Laboratory of Genetic Diagnosis, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Amélie Piton
- Department of Translational Medicine and Neurogenetics, Institut Génétique Biologie Moléculaire Cellulaire (IGBMC), Illkirch, France.,Laboratory of Genetic Diagnosis, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - J Lawrence Merritt
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Lance H Rodan
- Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Wen-Hann Tan
- Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Lynne M Bird
- Division of Genetics, Department of Pediatrics, Rady Children's Hospital San Diego, University of California San Diego, San Diego, CA, USA
| | - Mark Nespeca
- Division of Neurology, Rady Children's Hospital, University of California, San Diego, CA, USA
| | - Joseph G Gleeson
- Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, CA, USA
| | - Yongjin Yoo
- Department of Biomedical Sciences, Seoul National University School of Medicine, Seoul, South Korea
| | - Murim Choi
- Department of Biomedical Sciences, Seoul National University School of Medicine, Seoul, South Korea
| | - Jong-Hee Chae
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University School of Medicine, Seoul, South Korea
| | | | | | - Manuela Pendziwiat
- Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel, Germany
| | - Judith S Verhoeven
- Department of Neurology, Academic Center for Epileptology, Heeze, The Netherlands
| | - Helenius J Schelhaas
- Department of Neurology, Academic Center for Epileptology, Heeze, The Netherlands
| | | | - Jakob Christensen
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - Nicola Specchio
- Neurology Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marina Trivisano
- Neurology Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Yvonne G Weber
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tüebingen, Tüebingen, Germany
| | - Caroline Nava
- Department of Genetics, La Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France.,Sorbonne Universities, UPMC Univ Paris 06, UMR S 1127, Inserm U 1127, CNRS UMR 7225, ICM, Paris, France
| | - Boris Keren
- Department of Genetics, La Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France.,Sorbonne Universities, UPMC Univ Paris 06, UMR S 1127, Inserm U 1127, CNRS UMR 7225, ICM, Paris, France
| | - Diane Doummar
- Assistance Publique-Hôpitaux de Paris, Neuropediatric Services, Hospital Armand Trousseau, Paris, France
| | - Elise Schaefer
- Medical Genetics, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Sarah Hopkins
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Holly Dubbs
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Medical Center, New York, NY, USA
| | - Jessica E Shaw
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Medical Center, New York, NY, USA
| | - Laura Pisani
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Medical Center, New York, NY, USA
| | - Candace T Myers
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Sha Tang
- Division of Clinical Genomics, Ambry Genetics, Aliso Viejo, CA, USA
| | - Shan Tang
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Deb K Pal
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - John J Millichap
- Epilepsy Center and Division of Neurology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Gemma L Carvill
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | | | - Oriano Mecarelli
- Department of Neurology and Psychiatry, Neurophysiopathology and Neuromuscular Diseases, University of Sapeinza, Rome, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, and Maternal and Child Health, University of Genoa 'G. Gaslini" Institute, Genova, Italy
| | - Ingo Helbig
- Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel, Germany.,Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Guido Rubboli
- The Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,University of Copenhagen, Copenhagen, Denmark
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Rikke S Møller
- The Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,Institute for Regional Health Services Research, University of Southern Denmark, Odense, Denmark
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9
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Tran LH, Zupanc ML. Neurocognitive Comorbidities in Pediatric Epilepsy: Lessons in the Laboratory and Clinical Profile. Semin Pediatr Neurol 2017; 24:276-281. [PMID: 29249507 DOI: 10.1016/j.spen.2017.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Children with epilepsy are at risk for a variety of neurocognitive comorbidities. Animal models have increased our understanding about the neurobiological mechanisms underlying the association between seizures and these comorbidities. This article starts with an overview of the current data on animal model research, studying the influence of early-life seizures, followed by a summary of potential cellular and molecular mechanisms by which seizures can affect cognitive development. We then describe specific abnormal neuropsychological profiles that accompany specific pediatric epilepsy syndromes. Finally, we offer a potential guideline to the treatment and management of children with epilepsy and its neurocognitive comorbidities.
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Affiliation(s)
- Lily H Tran
- Department of Pediatrics, Pediatric Comprehensive Epilepsy Program, University of California, Irvine, Children's Hospital of Orange County, Orange, CA.
| | - Mary L Zupanc
- Department of Pediatrics and Neurology, University of California, Irvine, Children's Hospital of Orange County, Orange, CA
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10
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Nickels KC, Wirrell EC. Cognitive and Social Outcomes of Epileptic Encephalopathies. Semin Pediatr Neurol 2017; 24:264-275. [PMID: 29249506 DOI: 10.1016/j.spen.2017.10.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The term "epileptic encephalopathy" denotes a disorder in which seizures or frequent interictal discharges exacerbate neurocognitive dysfunction beyond what would be expected on the basis of underlying etiology. However, many underlying causes of epileptic encephalopathy also result in neurocognitive deficits, and it can be challenging to discern to what extent these deficits can be improved with better seizure control. Additionally, as seizures in these conditions are typically refractory, children are often exposed to high doses of multiple antiepileptic drugs which further exacerbate these comorbidities. This review will summarize the neurocognitive and social outcomes in children with various epileptic encephalopathies. Prompt, accurate diagnosis of epilepsy syndrome and etiology allows selection of optimal therapy to maximize seizure control, limiting the impact of ongoing seizures and frequent epileptiform abnormalities on the developing brain. Furthermore, mandatory screening for comorbidities allows early recognition and focused therapy for these commonly associated conditions to maximize neurocognitive outcome.
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Affiliation(s)
- Katherine C Nickels
- Divisions of Child and Adolescent Neurology and Epilepsy, Mayo Clinic, Rochester, MN
| | - Elaine C Wirrell
- Divisions of Child and Adolescent Neurology and Epilepsy, Mayo Clinic, Rochester, MN.
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11
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Canafoglia L, Ragona F, Panzica F, Piazza E, Freri E, Binelli S, Scaioli V, Avanzini G, Granata T, Franceschetti S. Movement-activated cortical myoclonus in Dravet syndrome. Epilepsy Res 2017; 130:47-52. [PMID: 28126647 DOI: 10.1016/j.eplepsyres.2017.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/04/2017] [Accepted: 01/15/2017] [Indexed: 10/20/2022]
Abstract
PURPOSE we characterized multifocal myoclonus in Dravet syndrome (DS) that was never systematically typified before. METHODS we studied EEG-EMG recordings of 19 consecutive patients, aged 2-29 years, with DS associated with SCN1A gene mutations to detect and evaluate myoclonus based on the spectrum of EMG activity on antagonist muscle pairs and cortico-muscular coherence (CMC). RESULTS multifocal action myoclonus was detected in all patients corresponding to brief EMG bursts, which occurred synchronously on antagonist muscles at a frequency peaking in beta band. There was significant CMC in beta band, and a cortico-muscular transfer time consistent with a cortical origin of the jerks. The somatosensory evoked potentials (SSEPs) were giant in only one patient who also showed exaggerated long-loop reflexes (LLRs). The nine patients who had experienced myoclonic seizures showed greater CMC. CONCLUSIONS The cortical myoclonus consistently observed in patients with DS shows features that are similar to those characterizing progressive myoclonus epilepsy, but differs because it does not have a severely worsening course and is not commonly associated with increased SSEPs or enhanced LLRs. This kind of myoclonus is an intrinsic feature of DS associated with SCN1A mutations, and may be a cause of disability. SIGNIFICANCE We hypothesize that myoclonus is generated in cortical motor areas by hyper-synchronous oscillations, which are possibly due to sodium channel dysfunction.
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Affiliation(s)
- Laura Canafoglia
- Neurophysiopathology and Epilepsy Centre, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
| | - Francesca Ragona
- Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Ferruccio Panzica
- Neurophysiopathology and Epilepsy Centre, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Elena Piazza
- Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Elena Freri
- Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Simona Binelli
- Neurophysiopathology and Epilepsy Centre, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Vidmer Scaioli
- Neurophysiopathology and Epilepsy Centre, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Giuliano Avanzini
- Neurophysiopathology and Epilepsy Centre, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Tiziana Granata
- Child Neurology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Silvana Franceschetti
- Neurophysiopathology and Epilepsy Centre, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
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12
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Shorvon S, Diehl B, Duncan J, Koepp M, Rugg-Gunn F, Sander J, Walker M, Wehner T. Epilepsy and Related Disorders. Neurology 2016. [DOI: 10.1002/9781118486160.ch7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
| | | | | | | | | | | | | | - Tim Wehner
- National Hospital for Neurology & Neurosurgery
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13
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Thomas RH, Zhang LM, Carvill GL, Archer JS, Heavin SB, Mandelstam SA, Craiu D, Berkovic SF, Gill DS, Mefford HC, Scheffer IE. CHD2 myoclonic encephalopathy is frequently associated with self-induced seizures. Neurology 2015; 84:951-8. [PMID: 25672921 DOI: 10.1212/wnl.0000000000001305] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE To delineate the phenotype of early childhood epileptic encephalopathy due to de novo mutations of CHD2, which encodes the chromodomain helicase DNA binding protein 2. METHODS We analyzed the medical history, MRI, and video-EEG recordings of 9 individuals with de novo CHD2 mutations and one with a de novo 15q26 deletion encompassing CHD2. RESULTS Seizures began at a mean of 26 months (12-42) with myoclonic seizures in all 10 cases. Seven exhibited exquisite clinical photosensitivity; 6 self-induced with the television. Absence seizures occurred in 9 patients including typical (4), atypical (2), and absence seizures with eyelid myoclonias (4). Generalized tonic-clonic seizures occurred in 9 of 10 cases with a mean onset of 5.8 years. Convulsive and nonconvulsive status epilepticus were later features (6/10, mean onset 9 years). Tonic (40%) and atonic (30%) seizures also occurred. In 3 cases, an unusual seizure type, the atonic-myoclonic-absence was captured on video. A phenotypic spectrum was identified with 7 cases having moderate to severe intellectual disability and refractory seizures including tonic attacks. Their mean age at onset was 23 months. Three cases had a later age at onset (34 months) with relative preservation of intellect and an initial response to antiepileptic medication. CONCLUSION The phenotypic spectrum of CHD2 encephalopathy has distinctive features of myoclonic epilepsy, marked clinical photosensitivity, atonic-myoclonic-absence, and intellectual disability ranging from mild to severe. Recognition of this genetic entity will permit earlier diagnosis and enable the development of targeted therapies.
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Affiliation(s)
- Rhys H Thomas
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Lin Mei Zhang
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Gemma L Carvill
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - John S Archer
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Sinéad B Heavin
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Simone A Mandelstam
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Dana Craiu
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Samuel F Berkovic
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Deepak S Gill
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Heather C Mefford
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia
| | - Ingrid E Scheffer
- From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
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Lin X, O'Malley H, Chen C, Auerbach D, Foster M, Shekhar A, Zhang M, Coetzee W, Jalife J, Fishman GI, Isom L, Delmar M. Scn1b deletion leads to increased tetrodotoxin-sensitive sodium current, altered intracellular calcium homeostasis and arrhythmias in murine hearts. J Physiol 2014; 593:1389-407. [PMID: 25772295 DOI: 10.1113/jphysiol.2014.277699] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 08/07/2014] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Na(+) current (INa) results from the integrated function of a molecular aggregate (the voltage-gated Na(+) channel complex) that includes the β subunit family. Mutations or rare variants in Scn1b (encoding the β1 and β1B subunits) have been associated with various inherited arrhythmogenic syndromes, including Brugada syndrome and sudden unexpected death in patients with epilepsy. We used Scn1b null mice to understand better the relation between Scn1b expression, and cardiac electrical function. Loss of Scn1b caused, among other effects, increased amplitude of tetrodotoxin-sensitive INa, delayed after-depolarizations, triggered beats, delayed Ca(2+) transients, frequent spontaneous calcium release events and increased susceptibility to polymorphic ventricular arrhythmias. Most alterations in Ca(2+) homeostasis were prevented by 100 nM tetrodotoxin. We propose that life-threatening arrhythmias in patients with mutations in Scn1b, a gene classically defined as ancillary to the Na(+) channel α subunit, can be partly consequent to disrupted intracellular Ca(2+) homeostasis. ABSTRACT Na(+) current (INa) is determined not only by the properties of the pore-forming voltage-gated Na(+) channel (VGSC) α subunit, but also by the integrated function of a molecular aggregate (the VGSC complex) that includes the VGSC β subunit family. Mutations or rare variants in Scn1b (encoding the β1 and β1B subunits) have been associated with various inherited arrhythmogenic syndromes, including cases of Brugada syndrome and sudden unexpected death in patients with epilepsy. Here, we have used Scn1b null mouse models to understand better the relation between Scn1b expression, and cardiac electrical function. Using a combination of macropatch and scanning ion conductance microscopy we show that loss of Scn1b in juvenile null animals resulted in increased tetrodotoxin-sensitive INa but only in the cell midsection, even before full T-tubule formation; the latter occurred concurrent with increased message abundance for the neuronal Scn3a mRNA, suggesting increased abundance of tetrodotoxin-sensitive NaV 1.3 protein and yet its exclusion from the region of the intercalated disc. Ventricular myocytes from cardiac-specific adult Scn1b null animals showed increased Scn3a message, prolonged action potential repolarization, presence of delayed after-depolarizations and triggered beats, delayed Ca(2+) transients and frequent spontaneous Ca(2+) release events and at the whole heart level, increased susceptibility to polymorphic ventricular arrhythmias. Most alterations in Ca(2+) homeostasis were prevented by 100 nM tetrodotoxin. Our results suggest that life-threatening arrhythmias in patients with mutations in Scn1b, a gene classically defined as ancillary to the Na(+) channel α subunit, can be partly consequent to disrupted intracellular Ca(2+) homeostasis in ventricular myocytes.
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Affiliation(s)
- Xianming Lin
- Leon H. Charney Division of Cardiology, New York University School of Medicine, New York, NY, USA
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Inoue T, Ihara Y, Tomonoh Y, Nakamura N, Ninomiya S, Fujita T, Ideguchi H, Yasumoto S, Zhang B, Hirose S. Early onset and focal spike discharges as indicators of poor prognosis for myoclonic-astatic epilepsy. Brain Dev 2014; 36:613-9. [PMID: 24055341 DOI: 10.1016/j.braindev.2013.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 07/19/2013] [Accepted: 08/14/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Myoclonic-astatic epilepsy (MAE) is an epileptic syndrome characterized by unique myoclonus, myoclonic-astatic, or astatic seizures in childhood. MAE prognosis vary from spontaneous remission to intractable seizures with profound mental retardation. AIM Identifying early risk factors may optimize the treatment of children with MAE. Our hypothesis is early onset age and focal spike discharges on EEG indicate a poor MAE prognosis. METHODS Using the medical records of 9 children with MAE, we analyzed their clinical histories, EEG findings, and seizure symptoms. All patients were given follow-up observations/treatments by our department for at least 2 years after MAE onset. RESULTS Five of the patients were given favorable prognoses because their seizures disappeared within 2 years of onset; the other 4 received poor prognoses because their seizures continued more than 2 years. MAE onset in patient with refractory seizures was earlier than that in those with a favorable prognosis (7-24 months vs. 23-38 months). All the patients with refractory seizures showed moderate or severe mental retardation. Among the 5 patients with good prognosis, EEGs showed two with focal spike discharges and three with only generalized spike discharges. In contrast, all cases with a poor prognosis had focal spike discharges. CONCLUSIONS MAE onset in patients with refractory seizures occurs earlier than in those with favorable prognosis. Prognosis was excellent when EEG findings show no focal spike discharges. Both early seizure onset and the focal spike discharges associated with MAE are indicators of poor prognosis.
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Affiliation(s)
- Takahito Inoue
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Yukiko Ihara
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Yuko Tomonoh
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Noriko Nakamura
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Shinya Ninomiya
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Takako Fujita
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Hiroshi Ideguchi
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Sawa Yasumoto
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Bo Zhang
- Department of Biochemistry, School of Medicine, Fukuoka University, Fukuoka, Japan
| | - Shinichi Hirose
- Department of Pediatrics, School of Medicine, Fukuoka University, Fukuoka, Japan.
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Altered cardiac electrophysiology and SUDEP in a model of Dravet syndrome. PLoS One 2013; 8:e77843. [PMID: 24155976 PMCID: PMC3796479 DOI: 10.1371/journal.pone.0077843] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 09/04/2013] [Indexed: 12/04/2022] Open
Abstract
Objective Dravet syndrome is a severe form of intractable pediatric epilepsy with a high incidence of SUDEP: Sudden Unexpected Death in epilepsy. Cardiac arrhythmias are a proposed cause for some cases of SUDEP, yet the susceptibility and potential mechanism of arrhythmogenesis in Dravet syndrome remain unknown. The majority of Dravet syndrome patients have denovo mutations in SCN1A, resulting in haploinsufficiency. We propose that, in addition to neuronal hyperexcitability, SCN1A haploinsufficiency alters cardiac electrical function and produces arrhythmias, providing a potential mechanism for SUDEP. Methods Postnatal day 15-21 heterozygous SCN1A-R1407X knock-in mice, expressing a human Dravet syndrome mutation, were used to investigate a possible cardiac phenotype. A combination of single cell electrophysiology and invivo electrocardiogram (ECG) recordings were performed. Results We observed a 2-fold increase in both transient and persistent Na+ current density in isolated Dravet syndrome ventricular myocytes that resulted from increased activity of a tetrodotoxin-resistant Na+ current, likely Nav1.5. Dravet syndrome myocytes exhibited increased excitability, action potential duration prolongation, and triggered activity. Continuous radiotelemetric ECG recordings showed QT prolongation, ventricular ectopic foci, idioventricular rhythms, beat-to-beat variability, ventricular fibrillation, and focal bradycardia. Spontaneous deaths were recorded in 2 DS mice, and a third became moribund and required euthanasia. Interpretation These data from single cell and whole animal experiments suggest that altered cardiac electrical function in Dravet syndrome may contribute to the susceptibility for arrhythmogenesis and SUDEP. These mechanistic insights may lead to critical risk assessment and intervention in human patients.
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Liu Y, Lopez-Santiago LF, Yuan Y, Jones JM, Zhang H, O’Malley HA, Patino GA, O’Brien JE, Rusconi R, Gupta A, Thompson RC, Natowicz MR, Meisler MH, Isom LL, Parent JM. Dravet syndrome patient-derived neurons suggest a novel epilepsy mechanism. Ann Neurol 2013; 74:128-39. [PMID: 23821540 PMCID: PMC3775921 DOI: 10.1002/ana.23897] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 02/25/2013] [Accepted: 03/01/2013] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Neuronal channelopathies cause brain disorders, including epilepsy, migraine, and ataxia. Despite the development of mouse models, pathophysiological mechanisms for these disorders remain uncertain. One particularly devastating channelopathy is Dravet syndrome (DS), a severe childhood epilepsy typically caused by de novo dominant mutations in the SCN1A gene encoding the voltage-gated sodium channel Na(v) 1.1. Heterologous expression of mutant channels suggests loss of function, raising the quandary of how loss of sodium channels underlying action potentials produces hyperexcitability. Mouse model studies suggest that decreased Na(v) 1.1 function in interneurons causes disinhibition. We aim to determine how mutant SCN1A affects human neurons using the induced pluripotent stem cell (iPSC) method to generate patient-specific neurons. METHODS Here we derive forebrain-like pyramidal- and bipolar-shaped neurons from 2 DS subjects and 3 human controls by iPSC reprogramming of fibroblasts. DS and control iPSC-derived neurons are compared using whole-cell patch clamp recordings. Sodium current density and intrinsic neuronal excitability are examined. RESULTS Neural progenitors from DS and human control iPSCs display a forebrain identity and differentiate into bipolar- and pyramidal-shaped neurons. DS patient-derived neurons show increased sodium currents in both bipolar- and pyramidal-shaped neurons. Consistent with increased sodium currents, both types of patient-derived neurons show spontaneous bursting and other evidence of hyperexcitability. Sodium channel transcripts are not elevated, consistent with a post-translational mechanism. INTERPRETATION These data demonstrate that epilepsy patient-specific iPSC-derived neurons are useful for modeling epileptic-like hyperactivity. Our findings reveal a previously unrecognized cell-autonomous epilepsy mechanism potentially underlying DS, and offer a platform for screening new antiepileptic therapies.
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Affiliation(s)
- Yu Liu
- Department of Neurology, University of Michigan Medical Center, Ann Arbor, MI
| | | | - Yukun Yuan
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, MI
| | - Julie M. Jones
- Department of Human Genetics, University of Michigan Medical Center, Ann Arbor, MI
| | - Helen Zhang
- Department of Neurology, University of Michigan Medical Center, Ann Arbor, MI
| | - Heather A. O’Malley
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, MI
| | - Gustavo A. Patino
- Department of Neurology, University of Michigan Medical Center, Ann Arbor, MI
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, MI
- Neuroscience Graduate Program, University of Michigan Medical Center, Ann Arbor, MI
| | - Janelle E. O’Brien
- Department of Human Genetics, University of Michigan Medical Center, Ann Arbor, MI
| | - Raffaella Rusconi
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, MI
| | - Ajay Gupta
- Neurological, Cleveland Clinic Lerner College of Medicine, Cleveland, OH
| | - Robert C. Thompson
- Department of Psychiatry, University of Michigan Medical Center, Ann Arbor, MI
- Neuroscience Graduate Program, University of Michigan Medical Center, Ann Arbor, MI
| | - Marvin R. Natowicz
- Genomic Medicine, Pediatric and Pathology, Laboratory Medicine Institutes, Cleveland Clinic, Cleveland Clinic Lerner College of Medicine, Cleveland, OH
- Neurological, Cleveland Clinic Lerner College of Medicine, Cleveland, OH
| | - Miriam H. Meisler
- Department of Human Genetics, University of Michigan Medical Center, Ann Arbor, MI
- Neuroscience Graduate Program, University of Michigan Medical Center, Ann Arbor, MI
| | - Lori L. Isom
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, MI
- Neuroscience Graduate Program, University of Michigan Medical Center, Ann Arbor, MI
| | - Jack M. Parent
- Department of Neurology, University of Michigan Medical Center, Ann Arbor, MI
- Neuroscience Graduate Program, University of Michigan Medical Center, Ann Arbor, MI
- VA Ann Arbor Healthcare System, Ann Arbor, MI
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Schmalbach B, Moeller B, von Spiczak S, Muhle H, Stephani U, Lang N. Seizure control in a patient with Dravet syndrome and cystic fibrosis. EPILEPSY & BEHAVIOR CASE REPORTS 2013; 1:42-44. [PMID: 25667824 PMCID: PMC4150651 DOI: 10.1016/j.ebcr.2013.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 02/23/2013] [Indexed: 06/04/2023]
Abstract
Satisfactory treatment of patients with Dravet syndrome (DS) is often difficult. Some success can be achieved with bromides, but cognitive side effects and disturbed vigilance may limit their use. Here, we present the case of a successfully treated patient with DS and remarkable features in the course of his disease: additionally to DS, the patient was diagnosed with cystic fibrosis (CF), another genetic channelopathy. Seizure freedom could be achieved under treatment with potassium bromide at the age of 15, but at the age of 20, adverse events made it necessary to stop bromide treatment. After conversion to valproic acid, the patient remained seizure-free, and neuropsychological tests demonstrated sustained improvement of cognition.
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Affiliation(s)
- Barbara Schmalbach
- Department of Neurology, Christian-Albrechts-University of Kiel, Arnold-Heller-Str. 3, Haus 41, 24105 Kiel, Germany
| | - Bettina Moeller
- Department of Neurology, Christian-Albrechts-University of Kiel, Arnold-Heller-Str. 3, Haus 41, 24105 Kiel, Germany
| | - Sarah von Spiczak
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Arnold-Heller-Str. 3, Haus 9, 24105 Kiel, Germany
| | - Hiltrud Muhle
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Arnold-Heller-Str. 3, Haus 9, 24105 Kiel, Germany
| | - Ulrich Stephani
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Arnold-Heller-Str. 3, Haus 9, 24105 Kiel, Germany
| | - Nicolas Lang
- Department of Neurology, Christian-Albrechts-University of Kiel, Arnold-Heller-Str. 3, Haus 41, 24105 Kiel, Germany
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Abstract
Epileptic myoclonus can be defined as an elementary electroclinical manifestation of epilepsy involving descending neurons, whose spatial (spread) or temporal (self-sustained repetition) amplification can trigger overt epileptic activity and can be classified as cortical (positive and negative), secondarily generalized, thalamo-cortical, and reticular. Cortical epileptic myoclonus represents a fragment of partial or symptomatic generalized epilepsy; thalamo-cortical epileptic myoclonus is a fragment of idiopathic generalized epilepsy. Reflex reticular myoclonus represents the clinical counterpart of fragments of hypersynchronous epileptic activity of neurons in the brainstem reticular formation. Epileptic myoclonus, in the setting of an epilepsy syndrome, can be only one component of a seizure, the only seizure manifestations, one of the multiple seizure types or a more stable condition that is manifested in a nonparoxysmal fashion and mimics a movement disorder. This complex correlation is more obvious in patients with epilepsia partialis continua in which cortical myoclonus and overt focal motor seizures usually start in the same somatic (and cortical) region. In patients with cortical tremor this correlation is less obvious and requires neurophysiological studies to be demonstrated.
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Affiliation(s)
- Renzo Guerrini
- Pediatric Neurology Unit and Laboratories, Children's Hospital A. Meyer - University of Florence, Florence, Italy.
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20
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Epileptic encephalopathies in adults and childhood. EPILEPSY RESEARCH AND TREATMENT 2012; 2012:205131. [PMID: 23056934 PMCID: PMC3465907 DOI: 10.1155/2012/205131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 03/28/2012] [Accepted: 06/10/2012] [Indexed: 02/02/2023]
Abstract
Epileptic encephalopathies are motor-mental retardations or cognitive disorders secondary to epileptic seizures or epileptiform activities. Encephalopaties due to brain damage, medications, or systemic diseases are generally not in the scope of this definition, but they may rarely accompany the condition. Appropriate differential diagnosis of epileptic seizures as well as subclinical electroencephalographic discharges are crucial for management of seizures and epileptiform discharges and relative regression of cognitive deterioration in long-term followup. Proper antiepileptic drug, hormonal treatment, or i.v. immunoglobulin choice play major role in prognosis. In this paper, we evaluated the current treatment approaches by reviewing clinical electrophysiological characteristics of epileptic encephalopathies.
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Sutter R, Kaplan PW. Electroencephalographic criteria for nonconvulsive status epilepticus: synopsis and comprehensive survey. Epilepsia 2012; 53 Suppl 3:1-51. [PMID: 22862158 DOI: 10.1111/j.1528-1167.2012.03593.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
There have been many attempts at defining the electroencephalography (EEG) characteristics of nonconvulsive status epilepticus (NCSE) without a universally accepted definition. This lack of consensus arises because the EEG expression of NCSE does not exist in isolation, but reflects status epilepticus under the variety of pathologic conditions that occur with age, cerebral development, encephalopathy, and epilepsy syndrome. Current NCSE definitions include "boundary conditions," in which electroencephalographic seizure activity occurs without apparent clinical seizures. Furthermore, what appears to one interpreter as status epilepticus, is not to another reader, reflecting the "art" of EEG interpretation. Seizures and epilepsy syndromes have undergone an evolution that has moved beyond a classification of focal or generalized conditions into a syndromic approach. It seems appropriate to make similar changes in the EEG analysis of the syndromes of NCSE. In effect, the literature on epilepsy classification has progressed to incorporate the different NCSE types with clinical descriptions, but the specific EEG evidence for these types is found largely in individual reports, and often by description only. NCSE classification of EEG patterns should derive from the aggregate of published EEG patterns in the respective clinical subtype, supported by an analysis of these EEG studies. The analysis that follows presents clinical descriptions and EEG patterns of NCSE in the neonatal period, infancy, childhood, adulthood, and late adulthood from a syndromic perspective based on age, encephalopathy, cerebral development, etiology, and syndrome. Proceeding from the proposed classification of status epilepticus syndromes in "Status epilepticus: its clinical features and treatment in children and adults" (published in 1994 by Cambridge University Press, New York), we have performed a systematic search for reports presenting EEG patterns of NCSE using the online medical search engine PubMed for 22 different search strategies. EEG patterns were reviewed by two board-certified epileptologists who reached consensus regarding presence of NCSE. From a total of 4,328 search results, 123 cases with corresponding EEG patterns could be allocated to underlying epilepsy syndromes. Typical characteristic, prominent electrographic patterns, and sequential arrangements are elucidated for the different NCSE syndromes. This compendium of patterns by NCSE syndrome classification with illustration of EEGs, and delineation of electroencephalographic features helps define the characteristics and semiologic borderlines among the types of NCSE.
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Affiliation(s)
- Raoul Sutter
- Division of Neurosciences Critical Care, Department of Anesthesiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
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22
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Bergqvist AC. Myoclonic astatic epilepsy and the use of the ketogenic diet. Epilepsy Res 2012; 100:258-60. [DOI: 10.1016/j.eplepsyres.2011.04.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 04/24/2011] [Indexed: 10/18/2022]
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24
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Guzzetta F. Cognitive and behavioral characteristics of children with Dravet syndrome: An overview. Epilepsia 2011; 52 Suppl 2:35-8. [DOI: 10.1111/j.1528-1167.2011.02999.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Lennox-Gastaut syndrome is an epilepsy syndrome that begins in childhood (between 1 and 8 years of age), worsens during latency and persists frequently into adulthood, is refractory to antiepileptic medications, and results in cognitive decline and behavioral problems in affected individuals. Seizure types consist primarily of axial tonic, atonic, and atypical absence; nocturnal tonic seizures are the most common seizure pattern in this population, but often are not one of the initial seizure patterns. Some patients also have myoclonic seizures; this seizure pattern is less frequent than the three preceding types. Although there are some cases that are cryptogenic, most are symptomatic, arising during prenatal and perinatal periods from intrauterine infections, and vascular insults to the brain. Examples of causes of Lennox-Gastaut syndrome include migrational abnormalities of the brain, late effects of CNS infections, certain genetic disorders such as tuberous sclerosis, and inherited metabolic disorders. The difficulty early in the course of Lennox-Gastaut syndrome is distinguishing this diagnosis from severe myoclonic epilepsy of infancy (Dravet syndrome) or from myoclonic-astatic epilepsy (Doose syndrome), as the seizure patterns in these three syndromes may overlap at the onset. EEG is a helpful diagnostic tool in the diagnosis of Lennox-Gastaut syndrome, usually demonstrating high voltage, bifrontal 1.5-2.5 Hz spike and wave complexes interictally, and attenuation with paroxysmal fast activity (10-13 Hz) during the ictal phase. Treatment options for Lennox-Gastaut syndrome have been less than optimal. In recent years, several drugs have been tested and approved for the treatment of this syndrome; these include felbamate, lamotrigine, topiramate, and rufinamide. The long-term outcome does not appear to be any better with the newer antiepileptic drugs than when using earlier prescribed antiepileptic drugs or polytherapy. Treatment options other than antiepileptic drugs include a ketogenic diet, vagus nerve stimulation, and corpus callosotomy. Long-term outcome of these patients relative to seizure control and cognition is poor. Most develop moderate intellectual disability within a few years of onset of the syndrome. Many develop behavioral problems with inattention, hyperactivity, and aggression.
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Affiliation(s)
- Patricia K Crumrine
- University of Pittsburgh School of Medicine, Children's Hospital of Pittsburgh, 45th Street & Penn Ave., Pittsburgh, PA 15201, USA.
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26
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Morse RP. Dravet syndrome: inroads into understanding epileptic encephalopathies. J Pediatr 2011; 158:354-9. [PMID: 21163495 DOI: 10.1016/j.jpeds.2010.10.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 08/17/2010] [Accepted: 10/21/2010] [Indexed: 12/17/2022]
Affiliation(s)
- Richard P Morse
- Section of Neurology and Development, Department of Pediatrics, Children's Hospital at Dartmouth, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA.
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27
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Zhai Q, Gui J, Zhang Y, Qiao H. Children treated for epileptic encephalopathies show improved glucose metabolism. Pediatr Int 2010; 52:883-7. [PMID: 20735805 DOI: 10.1111/j.1442-200x.2010.03232.x] [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] [Indexed: 11/29/2022]
Abstract
Epileptic neurological disorders in infants are often difficult to distinguish, and call for disparate treatments. Positron emission tomography (PET) using an [18F] fluoro-2-deoxyglucose (18FDG) tracer, is a powerful non-invasive technique successful in improving the diagnosis of a number of conditions. Interestingly, this technique has shown that cerebral glucose hypometabolism is present in children with epileptic encephalopathies (EE). Ten children with age-dependent EE were recruited and routine 18FDG PET images were evaluated for their ability to indicate cerebral glucose metabolism both before and after anti-epileptic treatment. We found that there is diffuse glucose hypometabolism in both hemispheres before treatment, indicating EE. Following treatment, the number of epileptic episodes significantly decreased (P < 0.05), while cerebral glucose metabolism improved. Our findings suggest that 18FDG PET can be utilized to monitor cerebral glucose metabolism as a measure of treatment progress in EE.
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Affiliation(s)
- Qiongxiang Zhai
- Department of Pediatrics, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangdong Neuroscience Institute, Guangzhou, China.
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Parisi P, Spalice A, Nicita F, Papetti L, Ursitti F, Verrotti A, Iannetti P, Villa MP. "Epileptic encephalopathy" of infancy and childhood: electro-clinical pictures and recent understandings. Curr Neuropharmacol 2010; 8:409-21. [PMID: 21629447 PMCID: PMC3080596 DOI: 10.2174/157015910793358196] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 03/31/2010] [Accepted: 04/08/2010] [Indexed: 12/04/2022] Open
Abstract
There is growing interest in the diagnosis of cognitive impairment among children with epilepsy. It is well known that status of seizures control has to be carefully investigated because it can be sufficient "per se" to cause progressive mental deterioration conditions. Subclinical electroencephalographic discharges may have subtle effects on cognition, learning and sleep patterns, even in the absence of clinical or sub-clinical seizures. In this respect, electroencephalographic monitoring (long-term and nocturnal recording) and in particular an all night video-polysomnography (V-NPSG) record can be crucial to detect the presence of unrecognized seizures and/or an inter-ictal nocturnal EEG discharge increasing. Epileptic encephalopathies (EE) are a group of conditions in which the higher cognitive functions are deteriorate as a consequence of epileptic activity, which, in fact, consists of frequent seizures and/or florid and prolonged interictal paroxysmal discharges, focal or generalized. AEDs represent the first line in opposing the burden of both, the poor seizures control and the poor interictal discharges control, in the cognitive deterioration of EE affected children. Thus, to improve the long-term cognitive/behavioural prognosis in these refractory epileptic children, it should be taken into account both a good seizures control and a strict sleep control, choosing carefully antiepileptic drugs which are able to control not only seizures clinically recognizable but even the EEG discharges onset and its increasing and spreading during sleep. Here, we review the efficacy and safety of the newer AEDs that, to date, are used in the treatment of EE in infancy and childhood.
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Affiliation(s)
- Pasquale Parisi
- Child Neurology, Headache Paediatric Center, Paediatric Sleep Centre, II Faculty of Medicine, “Sapienza University” c/o Sant’Andrea Hospital, Rome, Italy
| | - Alberto Spalice
- Child Neurology, Paediatric Department, I Faculty of Medicine, “Sapienza University” c/o Policlinico Umberto I, Rome, Italy
| | - Francesco Nicita
- Child Neurology, Paediatric Department, I Faculty of Medicine, “Sapienza University” c/o Policlinico Umberto I, Rome, Italy
| | - Laura Papetti
- Child Neurology, Paediatric Department, I Faculty of Medicine, “Sapienza University” c/o Policlinico Umberto I, Rome, Italy
| | - Fabiana Ursitti
- Child Neurology, Paediatric Department, I Faculty of Medicine, “Sapienza University” c/o Policlinico Umberto I, Rome, Italy
| | - Alberto Verrotti
- Child Neurology, Pediatric Department, University of Chieti, Italy
| | - Paola Iannetti
- Child Neurology, Paediatric Department, I Faculty of Medicine, “Sapienza University” c/o Policlinico Umberto I, Rome, Italy
| | - Maria Pia Villa
- Child Neurology, Headache Paediatric Center, Paediatric Sleep Centre, II Faculty of Medicine, “Sapienza University” c/o Sant’Andrea Hospital, Rome, Italy
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29
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Arzimanoglou A. Dravet syndrome: From electroclinical characteristics to molecular biology. Epilepsia 2009; 50 Suppl 8:3-9. [DOI: 10.1111/j.1528-1167.2009.02228.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Managing severe epilepsy syndromes of early childhood is challenging as the seizures are typically resistant to treatment and may cause disabling mental and behavioral problems in later life. A comprehensive treatment plan includes pharmacologic, nonpharmacologic, and surgical options. This article reviews clinical studies examining the efficacies of antiepileptic medications in reducing seizure frequency in Dravet syndrome, Doose syndrome, and Lennox-Gastaut syndrome. The benefits of the ketogenic diet for children with these severe epilepsies, together with the advantages of vagus nerve stimulation and corpus callosotomy in those patients with Lennox-Gastaut syndrome, are also discussed. Special treatment considerations for each syndrome are also highlighted to improve the management of patients with these syndromes.
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Affiliation(s)
- James W Wheless
- Department of Pediatric Neurology, University of Tennessee Health Science Center, Memphis, Tennessee 38105, USA.
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Abstract
The developing brain is particularly susceptible to seizures. Diffuse central nervous system pathology or injury in early infancy, when the brain is most vulnerable, may lead to catastrophic epilepsies such as Ohtahara's epileptic encephalopathy and early myoclonic epileptic encephalopathy. These epileptic encephalopathies are difficult to treat and have poor prognoses. As the brain undergoes programmed synaptogenesis, apoptosis, and myelination, the epilepsy phenotypes and electroencephalography (EEG) findings change, producing age-dependent epileptic encephalopathies. Specifically, as they grow older, 40% to 60% of infants with infantile spasms and a concomitant hypsarrhythmia on EEG will develop Lennox-Gastaut syndrome with tonic and atonic seizures, associated with a synchronous, generalized 1.5- to 2-Hz spike and slow wave discharges on EEG. In the context of age-dependent epileptic encephalopathies, as an epilepsy syndrome is evolving, it is often difficult to accurately diagnose the specific epilepsy syndrome in a young child who presents with seizures. It is the clinical evolution of the seizure types and the EEG that helps the clinician make an accurate diagnosis. As more is known about the underlying pathophysiology for the various epilepsy syndromes, not only the clinical picture and EEG but also a genetic blood test will be used to accurately diagnose a specific epilepsy syndrome. A case in point would be severe myoclonic epilepsy of infancy (classically known as Dravet syndrome) and severe myoclonic epilepsy of infancy-borderland/ borderline, which are associated with specific mutations in the sodium ion channel gene SCN1A.
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Affiliation(s)
- Mary L Zupanc
- Medical College of Wisconsin, Pediatric Comprehensive Epilepsy Program, Children's Hospital of Wisconsin, Milwaukee, Wisconsin 53201-1997, USA.
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Kilaru S, Bergqvist AGC. Current Treatment of Myoclonic Astatic Epilepsy: Clinical Experience at the Children's Hospital of Philadelphia. Epilepsia 2007; 48:1703-1707. [PMID: 17651420 DOI: 10.1111/j.1528-1167.2007.01186.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE Myoclonic astatic epilepsy (MAE) is a generalized epilepsy of early childhood. Little is known about the use of newer antiepileptic treatments (AET) in MAE. The purpose of this study was to describe the characteristics, treatment, and outcome of a contemporary MAE cohort exposed to the new generation AET. METHODS Charts of subjects with MAE treated between 1998 and 2005 were reviewed. RESULTS Twenty-three subjects (19 boys), with a median (range) follow-up of 38 (2- 86) months were identified. Thirty-nine percent had a family history of epilepsy, and 39% had family history of febrile seizures. Age at seizure onset was a median of 36 (12-24) months. Initial EEG was normal in 30%. When seizures ceased, EEG background and epileptiform abnormalities persisted in 17 and 58%, respectively. On average, each subject was exposed to five AET. The most frequently used AET was valproate (83%). Seizure freedom occurred spontaneously in three subjects, with ethosuximide and levetiracetam in one each, valproate and lamotrigine in two each, topiramate in three and the ketogenic diet (KD) in five subjects. By 36 months after seizure onset, 67% achieved seizure freedom. At the last visit, 43% were developmentally normal, 52% had mild, and 5% had moderate cognitive disabilities. Time to seizure freedom did not correlate with cognitive outcome. CONCLUSIONS The new generation of AET may offer significant benefit to children with MAE. The KD was the most effective AET in this series, and perhaps should be considered earlier in treatment.
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Affiliation(s)
- Sudha Kilaru
- Division of Neurology, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, U.S.A
| | - A G Christina Bergqvist
- Division of Neurology, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, U.S.A
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33
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Filippini M, Boni A, Dazzani G, Guerra A, Gobbi G. Neuropsychological Findings: Myoclonic Astatic Epilepsy (MAE) and Lennox-Gastaut Syndrome (LGS). Epilepsia 2006; 47 Suppl 2:56-9. [PMID: 17105463 DOI: 10.1111/j.1528-1167.2006.00691.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To identify a specific neuropsychological profile associated with myoclonic astatic epilepsy (MAE) and Lennox-Gastaut syndrome (LGS). METHODS Seven patients diagnosed with MAE and four patients diagnosed with LGS were selected from patients referred to our Child Neurology Unit. The patients were assessed both clinically (awake, sleep, Holter EEG, seizures frequency, and semiology) and neuropsychologically (IQ, language, attention, visuospatial and visuomotor abilities, and behavior). One representative case of each syndrome is presented here. RESULTS The clinical picture of the MAE patient resembled that of an MAE condition associated with transitory epileptic encephalopathy. The neuropsychological findings suggest that electroclinical anomalies can temporarily affect cognitive and behavioral functioning. Early effective antiepileptic drug (AED) treatment was found to improve cognitive outcome. In contrast, LGS was associated with mental retardation, which persisted after seizure control. CONCLUSIONS At present, it remains difficult to delineate a precise neuropsychological profile associated with MAE and LGS. The cognitive outcome of MAE is variable and depends on the clinical pattern. With regard to LGS, the hypothesis of a genetic predisposition underlying both the epilepsy and the mental retardation is still valid. Alternatively, exposure to subclinical electrophysiological anomalies during a critical period of cerebral development may be responsible for the mental retardation. At the time the clinical manifestations appear, drug treatment, even if effective, would have only limited impact on cognitive outcome. However, early multidisciplinary intervention may help to improve behavior and communicative abilities, enhancing the quality of life of these children and their families.
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Affiliation(s)
- Melissa Filippini
- Child Neurology Unit, Epilepsy Center, Neuropsychological Laboratory for Children with Epilepsy, Maggiore "C. A. Pizzardi" Hospital, Bologna, Italy.
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Abstract
An increasing number of infantile epilepsy syndromes have been recognized. However, a significant number of infants (children aged 1-24 months) do not fit in any of the currently used subcategories. This article reviews the clinical presentation, electroencephalographic findings, evolution, and management of the following entities: early infantile epileptic encephalopathy, early myoclonic epilepsy, infantile spasms/West syndrome, severe myoclonic epilepsy of infancy, myoclonic-astatic epilepsy, generalized epilepsy with febrile seizures plus, malignant migrating partial seizures of infancy, hemiconvulsions-hemiplegia-epilepsy, benign myoclonic epilepsy, and benign familial/nonfamilial infantile seizures. Issues related to their classification are addressed.
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Affiliation(s)
- Christian M Korff
- Epilepsy Center, Children's Memorial Hospital, Chicago, Illinois 60614-3394, USA
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Abstract
10.5 million children worldwide are estimated to have active epilepsy. Over the past 15 years, syndrome-oriented clinical and EEG diagnosis, and better aetiological diagnosis, especially supported by neuroimaging, has helped to clarify the diversity of epilepsy in children, and has improved management. Perinatal and postinfective encephalopathy, cortical dysplasia, and hippocampal sclerosis account for the most severe symptomatic epilepsies. Ion channel defects can underlie both benign age-related disorders and severe epileptic encephalopathies with a progressive disturbance in cerebral function. However, the reasons for age-related expression in children are not understood. Neither are the mechanisms whereby an epileptic encephalopathy originates. Several new drugs have been recently introduced but have provided limited therapeutic benefits. However, treatment and quality of life have improved because the syndrome-specific efficacy profile of drugs is better known, and there is heightened awareness that compounds with severe cognitive side-effects and heavy polytherapies should be avoided. Epilepsy surgery is an important option for a few well-selected individuals, but should be considered with great caution when there is no apparent underlying brain lesion.
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Affiliation(s)
- Renzo Guerrini
- Department of Child Neurology and Psychiatry, University of Pisa and IRCCS Fondazione Stella Maris, 56018 Calambrone, Pisa, Italy.
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36
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Kim MJ, Kim YO, Kim SH, Choi WY, Byun HS, Kim CJ, Woo YJ. Clinical characteristics and outcomes of status epilepticus as an initial seizure in children. KOREAN JOURNAL OF PEDIATRICS 2006. [DOI: 10.3345/kjp.2006.49.6.659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Mi Jeong Kim
- Department of Pediatrics, College of Medicine, Chonnam National University, Gwangju, Korea
| | - Young Ok Kim
- Department of Pediatrics, College of Medicine, Chonnam National University, Gwangju, Korea
| | - Sun Hee Kim
- Department of Pediatrics, College of Medicine, Chonnam National University, Gwangju, Korea
| | - Woo Yeon Choi
- Department of Pediatrics, College of Medicine, Chonnam National University, Gwangju, Korea
| | - Hyung Suk Byun
- Department of Pediatrics, College of Medicine, Seonam University, Gwangju, Korea
| | - Chan Jong Kim
- Department of Pediatrics, College of Medicine, Chonnam National University, Gwangju, Korea
| | - Young Jong Woo
- Department of Pediatrics, College of Medicine, Chonnam National University, Gwangju, Korea
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37
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Scheffer IE, Harkin LA, Dibbens LM, Mulley JC, Berkovic SF. Neonatal Epilepsy Syndromes and Generalized Epilepsy with Febrile Seizures Plus (GEFS+). Epilepsia 2005; 46 Suppl 10:41-7. [PMID: 16359471 DOI: 10.1111/j.1528-1167.2005.00358.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
MESH Headings
- Child, Preschool
- Epilepsies, Myoclonic/genetics
- Epilepsy, Benign Neonatal/diagnosis
- Epilepsy, Benign Neonatal/genetics
- Epilepsy, Generalized/diagnosis
- Epilepsy, Generalized/genetics
- Female
- Genetic Heterogeneity
- Humans
- Infant
- KCNQ2 Potassium Channel/genetics
- KCNQ3 Potassium Channel/genetics
- Male
- Mutation
- NAV1.1 Voltage-Gated Sodium Channel
- Nerve Tissue Proteins/genetics
- Phenotype
- Receptors, GABA-A/genetics
- Receptors, GABA-B/genetics
- Seizures, Febrile/diagnosis
- Seizures, Febrile/genetics
- Sodium Channels/genetics
- Voltage-Gated Sodium Channel beta-1 Subunit
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Affiliation(s)
- Ingrid E Scheffer
- Department of Medicine (Neurology), The University of Melbourne, Austin Health, Melbourne, Victoria.
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38
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Meisler MH, Kearney JA. Sodium channel mutations in epilepsy and other neurological disorders. J Clin Invest 2005; 115:2010-7. [PMID: 16075041 PMCID: PMC1180547 DOI: 10.1172/jci25466] [Citation(s) in RCA: 357] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Since the first mutations of the neuronal sodium channel SCN1A were identified 5 years ago, more than 150 mutations have been described in patients with epilepsy. Many are sporadic mutations and cause loss of function, which demonstrates haploinsufficiency of SCN1A. Mutations resulting in persistent sodium current are also common. Coding variants of SCN2A, SCN8A, and SCN9A have also been identified in patients with seizures, ataxia, and sensitivity to pain, respectively. The rapid pace of discoveries suggests that sodium channel mutations are significant factors in the etiology of neurological disease and may contribute to psychiatric disorders as well.
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Affiliation(s)
- Miriam H Meisler
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan 48109-0618, USA.
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