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Singh V, Auerbach DS. Neurocardiac pathologies associated with potassium channelopathies. Epilepsia 2024. [PMID: 39087855 DOI: 10.1111/epi.18066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 07/10/2024] [Accepted: 07/10/2024] [Indexed: 08/02/2024]
Abstract
Voltage-gated potassium channels are expressed throughout the human body and are essential for physiological functions. These include delayed rectifiers, A-type channels, outward rectifiers, and inward rectifiers. They impact electrical function in the heart (repolarization) and brain (repolarization and stabilization of the resting membrane potential). KCNQx and KCNHx encode Kv7.x and Kv11.x proteins, which form delayed rectifier potassium channels. KCNQx and KCNHx channelopathies are associated with both cardiac and neuronal pathologies. These include electrocardiographic abnormalities, cardiac arrhythmias, sudden cardiac death (SCD), epileptiform discharges, seizures, bipolar disorder, and sudden unexpected death in epilepsy (SUDEP). Due to the ubiquitous expression of KCNQx and KCNHx channels, abnormalities in their function can be particularly harmful, increasing the risk of sudden death. For example, KCNH2 variants have a dual role in both cardiac and neuronal pathologies, whereas KCNQ2 and KCNQ3 variants are associated with severe and refractory epilepsy. Recurrent and uncontrolled seizures lead to secondary abnormalities, which include autonomics, cardiac electrical function, respiratory drive, and neuronal electrical activity. Even with a wide array of anti-seizure therapies available on the market, one-third of the more than 70 million people worldwide with epilepsy have uncontrolled seizures (i.e., intractable/drug-resistant epilepsy), which negatively impact neurodevelopment and quality of life. To capture the current state of the field, this review examines KCNQx and KCNHx expression patterns and electrical function in the brain and heart. In addition, it discusses several KCNQx and KCNHx variants that have been clinically and electrophysiologically characterized. Because these channel variants are associated with multi-system pathologies, such as epileptogenesis, Kv7 channel modulators provide a potential anti-seizure therapy, particularly for people with intractable epilepsy. Ultimately an increased understanding of the role of Kv channels throughout the body will fuel the development of innovative, safe, and effective therapies for people at a high risk of sudden death (SCD and SUDEP).
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Affiliation(s)
- Veronica Singh
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - David S Auerbach
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York, USA
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2
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Wang X, Ma J, Dong Y, Ren X, Li R, Yang G, She G, Tan Y, Chen S. Exploration on the potential efficacy and mechanism of methyl salicylate glycosides in the treatment of schizophrenia based on bioinformatics, molecular docking and dynamics simulation. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2024; 10:64. [PMID: 39019913 PMCID: PMC11255270 DOI: 10.1038/s41537-024-00484-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Accepted: 07/02/2024] [Indexed: 07/19/2024]
Abstract
The etiological and therapeutic complexities of schizophrenia (SCZ) persist, prompting exploration of anti-inflammatory therapy as a potential treatment approach. Methyl salicylate glycosides (MSGs), possessing a structural parent nucleus akin to aspirin, are being investigated for their therapeutic potential in schizophrenia. Utilizing bioinformation mining, network pharmacology, molecular docking and dynamics simulation, the potential value and mechanism of MSGs (including MSTG-A, MSTG-B, and Gaultherin) in the treatment of SCZ, as well as the underlying pathogenesis of the disorder, were examined. 581 differentially expressed genes related to SCZ were identified in patients and healthy individuals, with 349 up-regulated genes and 232 down-regulated genes. 29 core targets were characterized by protein-protein interaction (PPI) network, with the top 10 core targets being BDNF, VEGFA, PVALB, KCNA1, GRIN2A, ATP2B2, KCNA2, APOE, PPARGC1A and SCN1A. The pathogenesis of SCZ primarily involves cAMP signaling, neurodegenerative diseases and other pathways, as well as regulation of ion transmembrane transport. Molecular docking analysis revealed that the three candidates exhibited binding activity with certain targets with binding affinities ranging from -4.7 to -109.2 kcal/mol. MSTG-A, MSTG-B and Gaultherin show promise for use in the treatment of SCZ, potentially through their ability to modulate the expression of multiple genes involved in synaptic structure and function, ion transport, energy metabolism. Molecular dynamics simulation revealed good binding abilities between MSTG-A, MSTG-B, Gaultherin and ATP2B2. It suggests new avenues for further investigation in this area.
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Affiliation(s)
- Xiuhuan Wang
- Peking University HuiLongGuan Clinical Medical School, Beijing HuiLongGuan Hospital, Beijing, 100096, PR China
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, PR China
| | - Jiamu Ma
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, PR China
| | - Ying Dong
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, PR China
| | - Xueyang Ren
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, PR China
| | - Ruoming Li
- Peking University HuiLongGuan Clinical Medical School, Beijing HuiLongGuan Hospital, Beijing, 100096, PR China
| | - Guigang Yang
- Peking University HuiLongGuan Clinical Medical School, Beijing HuiLongGuan Hospital, Beijing, 100096, PR China
| | - Gaimei She
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 102488, PR China.
| | - Yunlong Tan
- Peking University HuiLongGuan Clinical Medical School, Beijing HuiLongGuan Hospital, Beijing, 100096, PR China.
| | - Song Chen
- Peking University HuiLongGuan Clinical Medical School, Beijing HuiLongGuan Hospital, Beijing, 100096, PR China.
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Qin C, Yang X, Zuo Z, Yuan P, Sun F, Luo X, Ye X, Cao Z, Chen Z, Wu Y. Differential potassium channel inhibitory activities of a novel thermostable degradation peptide BmKcug1a-P1 from scorpion medicinal material and its N-terminal truncated/restored peptides. Sci Rep 2024; 14:16092. [PMID: 38997408 PMCID: PMC11245557 DOI: 10.1038/s41598-024-66794-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 07/03/2024] [Indexed: 07/14/2024] Open
Abstract
Thermally stable full-length scorpion toxin peptides and partially degraded peptides with complete disulfide bond pairing are valuable natural peptide resources in traditional Chinese scorpion medicinal material. However, their pharmacological activities are largely unknown. This study discovered BmKcug1a-P1, a novel N-terminal degraded peptide, in this medicinal material. BmKcug1a-P1 inhibited hKv1.2 and hKv1.3 potassium channels with IC50 values of 2.12 ± 0.27 μM and 1.54 ± 0.28 μM, respectively. To investigate the influence of N-terminal amino acid loss on the potassium channel inhibiting activities, three analogs (i.e., full-length BmKcug1a, BmKcug1a-P1-D2 and BmKcug1a-P1-D4) of BmKcug1a-P1 were prepared, and their potassium channel inhibiting activities on hKv1.3 channel were verified by whole-cell patch clamp technique. Interestingly, the potassium channel inhibiting activity of full-length BmKcug1a on the hKv1.3 channel was significantly improved compared to its N-terminal degraded form (BmKcug1a-P1), while the activities of two truncated analogs (i.e., BmKcug1a-P1-D2 and BmKcug1a-P1-D4) were similar to that of BmKcug1a-P1. Extensive alanine-scanning experiments identified the bonding interface (including two key functional residues, Asn30 and Arg34) of BmKcug1a-P1. Structural and functional dissection further elucidated whether N-terminal residues of the peptide are located at the bonding interface is important in determining whether the N-terminus significantly influences the potassium channel inhibiting activity of the peptide. Altogether, this research identified a novel N-terminal degraded active peptide, BmKcug1a-P1, from traditional Chinese scorpion medicinal material and elucidated how the N-terminus of peptides influences their potassium channel inhibiting activity, contributing to the functional identification and molecular truncation optimization of full-length and degraded peptides from traditional Chinese scorpion medicinal material Buthus martensii Karsch.
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Affiliation(s)
- Chenhu Qin
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan, 442000, China
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xuhua Yang
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Zheng Zuo
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Peixin Yuan
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Fang Sun
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan, 442000, China
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xudong Luo
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan, 442000, China
| | - Xiangdong Ye
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan, 442000, China
| | - Zhijian Cao
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Center for BioDrug Research, Wuhan University, Wuhan, 430072, China
| | - Zongyun Chen
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan, 442000, China.
- College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| | - Yingliang Wu
- College of Life Sciences, Wuhan University, Wuhan, 430072, China.
- Center for BioDrug Research, Wuhan University, Wuhan, 430072, China.
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Duma GM, Cuozzo S, Wilson L, Danieli A, Bonanni P, Pellegrino G. Excitation/Inhibition balance relates to cognitive function and gene expression in temporal lobe epilepsy: a high density EEG assessment with aperiodic exponent. Brain Commun 2024; 6:fcae231. [PMID: 39056027 PMCID: PMC11272395 DOI: 10.1093/braincomms/fcae231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 05/22/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Patients with epilepsy are characterized by a dysregulation of excitation/inhibition balance (E/I). The assessment of E/I may inform clinicians during the diagnosis and therapy management, even though it is rarely performed. An accessible measure of the E/I of the brain represents a clinically relevant feature. Here, we exploited the exponent of the aperiodic component of the power spectrum of the electroencephalography (EEG) signal, as a non-invasive and cost-effective proxy of the E/I balance. We recorded resting-state activity with high-density EEG from 67 patients with temporal lobe epilepsy and 35 controls. We extracted the exponent of the aperiodic fit of the power spectrum from source-reconstructed EEG and tested differences between patients with epilepsy and controls. Spearman's correlation was performed between the exponent and clinical variables (age of onset, epilepsy duration and neuropsychology) and cortical expression of epilepsy-related genes derived from the Allen Human Brain Atlas. Patients with temporal lobe epilepsy showed a significantly larger exponent, corresponding to inhibition-directed E/I balance, in bilateral frontal and temporal regions. Lower E/I in the left entorhinal and bilateral dorsolateral prefrontal cortices corresponded to a lower performance of short-term verbal memory. Limited to patients with temporal lobe epilepsy, we detected a significant correlation between the exponent and the cortical expression of GABRA1, GRIN2A, GABRD, GABRG2, KCNA2 and PDYN genes. EEG aperiodic exponent maps the E/I balance non-invasively in patients with epilepsy and reveals a close relationship between altered E/I patterns, cognition and genetics.
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Affiliation(s)
- Gian Marco Duma
- Scientific Institute IRCCS E.Medea, Epilepsy and Clinical Neurophysiology Unit, 31015, Conegliano, Italy
| | - Simone Cuozzo
- Scientific Institute IRCCS E.Medea, Epilepsy and Clinical Neurophysiology Unit, 31015, Conegliano, Italy
| | - Luc Wilson
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Alberto Danieli
- Scientific Institute IRCCS E.Medea, Epilepsy and Clinical Neurophysiology Unit, 31015, Conegliano, Italy
| | - Paolo Bonanni
- Scientific Institute IRCCS E.Medea, Epilepsy and Clinical Neurophysiology Unit, 31015, Conegliano, Italy
| | - Giovanni Pellegrino
- Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London N6A5C1, Canada
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5
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Li K, Savitska D, Garaschuk O. K+ channel-mediated retarded maturation of interneurons and its role in neurodevelopmental disorders. Neural Regen Res 2024; 19:1403-1404. [PMID: 38051868 PMCID: PMC10883523 DOI: 10.4103/1673-5374.386409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 09/06/2023] [Indexed: 12/07/2023] Open
Affiliation(s)
- Kaizhen Li
- Laboratory of Systems Neuroscience, Department of Physiology, University of Bern, Bern, Switzerland
| | - Daria Savitska
- Institute of Physiology, Department of Neurophysiology, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Olga Garaschuk
- Institute of Physiology, Department of Neurophysiology, Eberhard Karls University of Tübingen, Tübingen, Germany
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6
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Shin HJ, Ko A, Kim SH, Lee JS, Kang HC. Unusual Voltage-Gated Sodium and Potassium Channelopathies Related to Epilepsy. J Clin Neurol 2024; 20:402-411. [PMID: 38951973 PMCID: PMC11220354 DOI: 10.3988/jcn.2023.0435] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/03/2024] [Accepted: 01/23/2024] [Indexed: 07/03/2024] Open
Abstract
BACKGROUND AND PURPOSE There is extensive literature on monogenic epilepsies caused by mutations in familiar channelopathy genes such as SCN1A. However, information on other less-common channelopathy genes is scarce. This study aimed to explore the genetic and clinical characteristics of patients diagnosed with unusual voltage-gated sodium and potassium channelopathies related to epilepsy. METHODS This observational, retrospective study analyzed pediatric patients with epilepsy who carried pathogenic variants of unusual voltage-gated sodium and potassium channelopathy genes responsible for seizure-associated phenotypes. Targeted next-generation sequencing (NGS) panel tests were performed between November 2016 and June 2022 at Severance Children's Hospital, Seoul, South Korea. Clinical characteristics and the treatment responses to different types of antiseizure medications were further analyzed according to different types of gene mutation. RESULTS This study included 15 patients with the following unusual voltage-gated sodium and potassium channelopathy genes: SCN3A (n=1), SCN4A (n=1), KCNA1 (n=1), KCNA2 (n=4), KCNB1 (n=6), KCNC1 (n=1), and KCNMA1 (n=1). NGS-based genetic testing identified 13 missense mutations (87%), 1 splice-site variant (7%), and 1 copy-number variant (7%). Developmental and epileptic encephalopathy was diagnosed in nine (60%) patients. Seizure freedom was eventually achieved in eight (53%) patients, whereas seizures persisted in seven (47%) patients. CONCLUSIONS Our findings broaden the genotypic and phenotypic spectra of less-common voltage-gated sodium and potassium channelopathies associated with epilepsy.
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Affiliation(s)
- Hui Jin Shin
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Ara Ko
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Se Hee Kim
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Joon Soo Lee
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Hoon-Chul Kang
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
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7
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Kalm T, Schob C, Völler H, Gardeitchik T, Gilissen C, Pfundt R, Klöckner C, Platzer K, Klabunde-Cherwon A, Ries M, Syrbe S, Beccaria F, Madia F, Scala M, Zara F, Hofstede F, Simon MEH, van Jaarsveld RH, Oegema R, van Gassen KLI, Holwerda SJB, Barakat TS, Bouman A, van Slegtenhorst M, Álvarez S, Fernández-Jaén A, Porta J, Accogli A, Mancardi MM, Striano P, Iacomino M, Chae JH, Jang S, Kim SY, Chitayat D, Mercimek-Andrews S, Depienne C, Kampmeier A, Kuechler A, Surowy H, Bertini ES, Radio FC, Mancini C, Pizzi S, Tartaglia M, Gauthier L, Genevieve D, Tharreau M, Azoulay N, Zaks-Hoffer G, Gilad NK, Orenstein N, Bernard G, Thiffault I, Denecke J, Herget T, Kortüm F, Kubisch C, Bähring R, Kindler S. Etiological involvement of KCND1 variants in an X-linked neurodevelopmental disorder with variable expressivity. Am J Hum Genet 2024; 111:1206-1221. [PMID: 38772379 PMCID: PMC11179411 DOI: 10.1016/j.ajhg.2024.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/25/2024] [Accepted: 04/25/2024] [Indexed: 05/23/2024] Open
Abstract
Utilizing trio whole-exome sequencing and a gene matching approach, we identified a cohort of 18 male individuals from 17 families with hemizygous variants in KCND1, including two de novo missense variants, three maternally inherited protein-truncating variants, and 12 maternally inherited missense variants. Affected subjects present with a neurodevelopmental disorder characterized by diverse neurological abnormalities, mostly delays in different developmental domains, but also distinct neuropsychiatric signs and epilepsy. Heterozygous carrier mothers are clinically unaffected. KCND1 encodes the α-subunit of Kv4.1 voltage-gated potassium channels. All variant-associated amino acid substitutions affect either the cytoplasmic N- or C-terminus of the channel protein except for two occurring in transmembrane segments 1 and 4. Kv4.1 channels were functionally characterized in the absence and presence of auxiliary β subunits. Variant-specific alterations of biophysical channel properties were diverse and varied in magnitude. Genetic data analysis in combination with our functional assessment shows that Kv4.1 channel dysfunction is involved in the pathogenesis of an X-linked neurodevelopmental disorder frequently associated with a variable neuropsychiatric clinical phenotype.
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Affiliation(s)
- Tassja Kalm
- Institute for Cellular and Integrative Physiology, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Claudia Schob
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Hanna Völler
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Thatjana Gardeitchik
- Department of Human Genetics, Radboud University Medical Center, Nijmegen 6525 GA, the Netherlands
| | - Christian Gilissen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen 6525 GA, the Netherlands
| | - Rolph Pfundt
- Department of Human Genetics, Radboud University Medical Center, Nijmegen 6525 GA, the Netherlands
| | - Chiara Klöckner
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Annick Klabunde-Cherwon
- Division of Pediatric Epileptology, Centre for Paediatric and Adolescent Medicine, University Hospital Heidelberg, 69120 Heidelberg, Germany
| | - Markus Ries
- Division of Pediatric Epileptology, Centre for Paediatric and Adolescent Medicine, University Hospital Heidelberg, 69120 Heidelberg, Germany
| | - Steffen Syrbe
- Division of Pediatric Epileptology, Centre for Paediatric and Adolescent Medicine, University Hospital Heidelberg, 69120 Heidelberg, Germany
| | - Francesca Beccaria
- Epilepsy Center, Department of Child Neuropsychiatry, Territorial Social-Health Agency, 46100 Mantova, Italy
| | - Francesca Madia
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Marcello Scala
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16145 Genoa, Italy
| | - Federico Zara
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16145 Genoa, Italy
| | - Floris Hofstede
- Department of General Pediatrics, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Marleen E H Simon
- Department of Clinical Genetics, University Medical Center Utrecht, Utrecht 3584 EA, the Netherlands
| | - Richard H van Jaarsveld
- Department of Clinical Genetics, University Medical Center Utrecht, Utrecht 3584 EA, the Netherlands
| | - Renske Oegema
- Department of Clinical Genetics, University Medical Center Utrecht, Utrecht 3584 EA, the Netherlands
| | - Koen L I van Gassen
- Department of Clinical Genetics, University Medical Center Utrecht, Utrecht 3584 EA, the Netherlands
| | - Sjoerd J B Holwerda
- Department of Clinical Genetics, University Medical Center Utrecht, Utrecht 3584 EA, the Netherlands
| | - Tahsin Stefan Barakat
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam 3000 CA, the Netherlands; ENCORE Expertise Center for Neurodevelopmental Disorders, Erasmus MC University Medical Center, Rotterdam 3000 CA, the Netherlands; Discovery Unit, Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Arjan Bouman
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Marjon van Slegtenhorst
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Sara Álvarez
- Genomics and Medicine, NIMGenetics, 28108 Madrid, Spain
| | - Alberto Fernández-Jaén
- Pediatric Neurology Department, Quironsalud University Hospital Madrid, School of Medicine, European University of Madrid, 28224 Madrid, Spain
| | - Javier Porta
- Genomics, Genologica Medica, 29016 Málaga, Spain
| | - Andrea Accogli
- Division of Medical Genetics, Department of Specialized Medicine, Montreal Children's Hospital, McGill University Health Centre, QC H4A 3J1 Montreal, Canada; Department of Human Genetics, McGill University, QC H4A 3J1 Montreal, Canada
| | | | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16145 Genoa, Italy; Pediatric Neurology and Neuromuscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Michele Iacomino
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Jong-Hee Chae
- Department of Pediatrics, Seoul National University College of Medicine, Seoul 110-744, Republic of Korea; Department of Genomic Medicine, Rare Disease Center, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - SeSong Jang
- Department of Pediatrics, Seoul National University College of Medicine, Seoul 110-744, Republic of Korea
| | - Soo Y Kim
- Department of Genomic Medicine, Rare Disease Center, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - David Chitayat
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto ON M5G 1E2 Toronto, Canada; Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for SickKids, University of Toronto, M5G 1X8 Toronto, Canada
| | - Saadet Mercimek-Andrews
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for SickKids, University of Toronto, M5G 1X8 Toronto, Canada; Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, AB T6G 2H7 Edmonton, Canada
| | - Christel Depienne
- Institute of Human Genetics, University Hospital Essen, University Duisburg-Essen, 45122 Essen, Germany
| | - Antje Kampmeier
- Institute of Human Genetics, University Hospital Essen, University Duisburg-Essen, 45122 Essen, Germany
| | - Alma Kuechler
- Institute of Human Genetics, University Hospital Essen, University Duisburg-Essen, 45122 Essen, Germany
| | - Harald Surowy
- Institute of Human Genetics, University Hospital Essen, University Duisburg-Essen, 45122 Essen, Germany
| | | | | | - Cecilia Mancini
- Molecular Genetics and Functional Genomics, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Simone Pizzi
- Molecular Genetics and Functional Genomics, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Marco Tartaglia
- Molecular Genetics and Functional Genomics, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Lucas Gauthier
- Department of Molecular Genetics and Cytogenomics, Rare and Autoinflammatory Diseases Unit, University Hospital of Montpellier, 34295 Montpellier, France
| | - David Genevieve
- Montpellier University, Inserm U1183, Montpellier, France; Department of Clinical Genetics, University Hospital of Montpellier, 34295 Montpellier, France
| | - Mylène Tharreau
- Department of Molecular Genetics and Cytogenomics, Rare and Autoinflammatory Diseases Unit, University Hospital of Montpellier, 34295 Montpellier, France
| | - Noy Azoulay
- The Genetic Institute of Maccabi Health Services, Rehovot 7610000, Israel; Raphael Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva 49100, Israel
| | - Gal Zaks-Hoffer
- Raphael Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva 49100, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Nesia K Gilad
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petah Tikvah 4920235, Israel
| | - Naama Orenstein
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petah Tikvah 4920235, Israel
| | - Geneviève Bernard
- Division of Medical Genetics, Department of Specialized Medicine, Montreal Children's Hospital, McGill University Health Centre, QC H4A 3J1 Montreal, Canada; Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University, Montreal, Canada; Child Health and Human Development Program, Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Isabelle Thiffault
- Genomic Medicine Center, Department of Pediatrics, Children's Mercy Kansas City, Kansas City, MO, USA; UKMC School of Medicine, University of Missouri Kansas City, Kansas City, MO, USA; Department of Pathology and Laboratory Medicine, Children's Mercy Kansas City, Kansas City, MO, USA
| | - Jonas Denecke
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Theresia Herget
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Fanny Kortüm
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Christian Kubisch
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Robert Bähring
- Institute for Cellular and Integrative Physiology, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Stefan Kindler
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
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Zhao T, Wang L, Chen F. Potassium channel-related epilepsy: Pathogenesis and clinical features. Epilepsia Open 2024; 9:891-905. [PMID: 38560778 PMCID: PMC11145612 DOI: 10.1002/epi4.12934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 03/11/2024] [Accepted: 03/17/2024] [Indexed: 04/04/2024] Open
Abstract
Variants in potassium channel-related genes are one of the most important mechanisms underlying abnormal neuronal excitation and disturbances in the cellular resting membrane potential. These variants can cause different forms of epilepsy, which can seriously affect the physical and mental health of patients, especially those with refractory epilepsy or status epilepticus, which are common among pediatric patients and are potentially life-threatening. Variants in potassium ion channel-related genes have been reported in few studies; however, to our knowledge, no systematic review has been published. This study aimed to summarize the epilepsy phenotypes, functional studies, and pharmacological advances associated with different potassium channel gene variants to assist clinical practitioners and drug development teams to develop evidence-based medicine and guide research strategies. PubMed and Google Scholar were searched for relevant literature on potassium channel-related epilepsy reported in the past 5-10 years. Various common potassium ion channel gene variants can lead to heterogeneous epilepsy phenotypes, and functional effects can result from gene deletions and compound effects. Administration of select anti-seizure medications is the primary treatment for this type of epilepsy. Most patients are refractory to anti-seizure medications, and some novel anti-seizure medications have been found to improve seizures. Use of targeted drugs to correct aberrant channel function based on the type of potassium channel gene variant can be used as an evidence-based pathway to achieve precise and individualized treatment for children with epilepsy. PLAIN LANGUAGE SUMMARY: In this article, the pathogenesis and clinical characteristics of epilepsy caused by different types of potassium channel gene variants are reviewed in the light of the latest research literature at home and abroad, with the expectation of providing a certain theoretical basis for the diagnosis and treatment of children with this type of disease.
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Affiliation(s)
- Tong Zhao
- Hebei Children's HospitalShijiazhuangHebeiChina
| | - Le Wang
- Hebei Children's HospitalShijiazhuangHebeiChina
| | - Fang Chen
- Hebei Children's HospitalShijiazhuangHebeiChina
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9
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Ng ACH, Chahine M, Scantlebury MH, Appendino JP. Channelopathies in epilepsy: an overview of clinical presentations, pathogenic mechanisms, and therapeutic insights. J Neurol 2024; 271:3063-3094. [PMID: 38607431 DOI: 10.1007/s00415-024-12352-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 03/24/2024] [Accepted: 03/25/2024] [Indexed: 04/13/2024]
Abstract
Pathogenic variants in genes encoding ion channels are causal for various pediatric and adult neurological conditions. In particular, several epilepsy syndromes have been identified to be caused by specific channelopathies. These encompass a spectrum from self-limited epilepsies to developmental and epileptic encephalopathies spanning genetic and acquired causes. Several of these channelopathies have exquisite responses to specific antiseizure medications (ASMs), while others ASMs may prove ineffective or even worsen seizures. Some channelopathies demonstrate phenotypic pleiotropy and can cause other neurological conditions outside of epilepsy. This review aims to provide a comprehensive exploration of the pathophysiology of seizure generation, ion channels implicated in epilepsy, and several genetic epilepsies due to ion channel dysfunction. We outline the clinical presentation, pathogenesis, and the current state of basic science and clinical research for these channelopathies. In addition, we briefly look at potential precision therapy approaches emerging for these disorders.
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Affiliation(s)
- Andy Cheuk-Him Ng
- Clinical Neuroscience and Pediatric Neurology, Department of Pediatrics, Cumming School of Medicine, Alberta Children's Hospital, University of Calgary, 28 Oki Drive NW, Calgary, AB, T3B 6A8, Canada
- Division of Neurology, Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta and Stollery Children's Hospital, Edmonton, AB, Canada
| | - Mohamed Chahine
- Department of Medicine, Faculty of Medicine, Université Laval, Quebec City, QC, Canada
- CERVO, Brain Research Centre, Quebec City, Canada
| | - Morris H Scantlebury
- Clinical Neuroscience and Pediatric Neurology, Department of Pediatrics, Cumming School of Medicine, Alberta Children's Hospital, University of Calgary, 28 Oki Drive NW, Calgary, AB, T3B 6A8, Canada
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, Calgary, Canada
| | - Juan P Appendino
- Clinical Neuroscience and Pediatric Neurology, Department of Pediatrics, Cumming School of Medicine, Alberta Children's Hospital, University of Calgary, 28 Oki Drive NW, Calgary, AB, T3B 6A8, Canada.
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10
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Rinaldi B, Bayat A, Zachariassen LG, Sun JH, Ge YH, Zhao D, Bonde K, Madsen LH, Awad IAA, Bagiran D, Sbeih A, Shah SM, El-Sayed S, Lyngby SM, Pedersen MG, Stenum-Berg C, Walker LC, Krey I, Delahaye-Duriez A, Emrick LT, Sully K, Murali CN, Burrage LC, Plaud Gonzalez JA, Parnes M, Friedman J, Isidor B, Lefranc J, Redon S, Heron D, Mignot C, Keren B, Fradin M, Dubourg C, Mercier S, Besnard T, Cogne B, Deb W, Rivier C, Milani D, Bedeschi MF, Di Napoli C, Grilli F, Marchisio P, Koudijs S, Veenma D, Argilli E, Lynch SA, Au PYB, Ayala Valenzuela FE, Brown C, Masser-Frye D, Jones M, Patron Romero L, Li WL, Thorpe E, Hecher L, Johannsen J, Denecke J, McNiven V, Szuto A, Wakeling E, Cruz V, Sency V, Wang H, Piard J, Kortüm F, Herget T, Bierhals T, Condell A, Ben-Zeev B, Kaur S, Christodoulou J, Piton A, Zweier C, Kraus C, Micalizzi A, Trivisano M, Specchio N, Lesca G, Møller RS, Tümer Z, Musgaard M, Gerard B, Lemke JR, Shi YS, Kristensen AS. Gain-of-function and loss-of-function variants in GRIA3 lead to distinct neurodevelopmental phenotypes. Brain 2024; 147:1837-1855. [PMID: 38038360 PMCID: PMC11068105 DOI: 10.1093/brain/awad403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 10/17/2023] [Accepted: 11/09/2023] [Indexed: 12/02/2023] Open
Abstract
AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptors (AMPARs) mediate fast excitatory neurotransmission in the brain. AMPARs form by homo- or heteromeric assembly of subunits encoded by the GRIA1-GRIA4 genes, of which only GRIA3 is X-chromosomal. Increasing numbers of GRIA3 missense variants are reported in patients with neurodevelopmental disorders (NDD), but only a few have been examined functionally. Here, we evaluated the impact on AMPAR function of one frameshift and 43 rare missense GRIA3 variants identified in patients with NDD by electrophysiological assays. Thirty-one variants alter receptor function and show loss-of-function or gain-of-function properties, whereas 13 appeared neutral. We collected detailed clinical data from 25 patients (from 23 families) harbouring 17 of these variants. All patients had global developmental impairment, mostly moderate (9/25) or severe (12/25). Twelve patients had seizures, including focal motor (6/12), unknown onset motor (4/12), focal impaired awareness (1/12), (atypical) absence (2/12), myoclonic (5/12) and generalized tonic-clonic (1/12) or atonic (1/12) seizures. The epilepsy syndrome was classified as developmental and epileptic encephalopathy in eight patients, developmental encephalopathy without seizures in 13 patients, and intellectual disability with epilepsy in four patients. Limb muscular hypotonia was reported in 13/25, and hypertonia in 10/25. Movement disorders were reported in 14/25, with hyperekplexia or non-epileptic erratic myoclonus being the most prevalent feature (8/25). Correlating receptor functional phenotype with clinical features revealed clinical features for GRIA3-associated NDDs and distinct NDD phenotypes for loss-of-function and gain-of-function variants. Gain-of-function variants were associated with more severe outcomes: patients were younger at the time of seizure onset (median age: 1 month), hypertonic and more often had movement disorders, including hyperekplexia. Patients with loss-of-function variants were older at the time of seizure onset (median age: 16 months), hypotonic and had sleeping disturbances. Loss-of-function and gain-of-function variants were disease-causing in both sexes but affected males often carried de novo or hemizygous loss-of-function variants inherited from healthy mothers, whereas affected females had mostly de novo heterozygous gain-of-function variants.
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Affiliation(s)
- Berardo Rinaldi
- Medical Genetics Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Allan Bayat
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
- Department of Epilepsy Genetics and Personalized Medicine, Danish Epilepsy Centre, Dianalund 4293, Denmark
- Department of Regional Health Research, University of Southern Denmark, Odense 5230Denmark
| | - Linda G Zachariassen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Jia-Hui Sun
- State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Department of Neurology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing 210032, China
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310030, China
| | - Yu-Han Ge
- State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Department of Neurology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing 210032, China
- Ministry of Education Key Laboratory of Model Animal for Disease Study, National Resource Center for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing 210032, China
| | - Dan Zhao
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Kristine Bonde
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Laura H Madsen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | | | - Duygu Bagiran
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Amal Sbeih
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Syeda Maidah Shah
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Shaymaa El-Sayed
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Signe M Lyngby
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Miriam G Pedersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Charlotte Stenum-Berg
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Louise Claudia Walker
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1H 8M5, Canada
| | - Ilona Krey
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig 04103, Germany
| | - Andrée Delahaye-Duriez
- Unité fonctionnelle de médecine génomique et génétique clinique, Hôpital Jean Verdier, Assistance Publique des Hôpitaux de Paris, Bondy 93140, France
- NeuroDiderot, UMR 1141, Inserm, Université Paris Cité, Paris 75019, France
- UFR SMBH, Université Sorbonne Paris Nord, Bobigny 93000, France
| | - Lisa T Emrick
- Division of Neurology and Developmental Neurosciences, Department of Pediatrics, Baylor College of Medicine, Texas Children’s Hospital, Houston, TX 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Krystal Sully
- Division of Neurology and Developmental Neurosciences, Department of Pediatrics, Baylor College of Medicine, Texas Children’s Hospital, Houston, TX 77030, USA
| | - Chaya N Murali
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lindsay C Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Julie Ana Plaud Gonzalez
- Division of Neurology and Developmental Neurosciences, Department of Pediatrics, Baylor College of Medicine, Texas Children’s Hospital, Houston, TX 77030, USA
| | - Mered Parnes
- Division of Neurology and Developmental Neurosciences, Department of Pediatrics, Baylor College of Medicine, Texas Children’s Hospital, Houston, TX 77030, USA
- Pediatric Movement Disorders Clinic, Texas Children’s Hospital and Baylor College of Medicine, Houston, TX 77030, USA
| | - Jennifer Friedman
- Rady Children’s Institute for Genomic Medicine, San Diego, CA 92123, USA
- Department of Neurosciences, University of California San Diego, San Diego, CA 92123, USA
- Department of Pediatrics, University of California San Diego, San Diego, CA 92123, USA
| | - Bertrand Isidor
- Nantes Université, CHU Nantes, Service de Génétique Médicale, Nantes 44000, France
| | - Jérémie Lefranc
- Pediatric Neurophysiology Department, CHU de Brest, Brest 29200, France
| | - Sylvia Redon
- Service de Génétique Médicale, CHU de Brest, Brest 29200, France
- Université de Brest, CHU de Brest, UMR 1078, Brest F29200, France
| | - Delphine Heron
- APHP Sorbonne Université, Département de Génétique, Hôpital Armand Trousseau and Groupe Hospitalier Pitié-Salpêtrière, Paris 75013, France
- Centre de Référence Déficiences Intellectuelles de Causes Rares, Paris 75013, France
| | - Cyril Mignot
- APHP Sorbonne Université, Département de Génétique, Hôpital Armand Trousseau and Groupe Hospitalier Pitié-Salpêtrière, Paris 75013, France
- Centre de Référence Déficiences Intellectuelles de Causes Rares, Paris 75013, France
| | - Boris Keren
- Genetic Department, APHP, Sorbonne Université, Pitié-Salpêtrière Hospital, Paris 75013, France
| | - Mélanie Fradin
- Service de Génétique Médicale, Hôpital Sud, CHU de Rennes, Rennes 35200, France
| | - Christele Dubourg
- Service de Génétique Moléculaire et Génomique, CHU de Rennes, Rennes 35200, France
- Université de Rennes, CNRS, Institut de Genetique et Developpement de Rennes, UMR 6290, Rennes 35200, France
| | - Sandra Mercier
- Nantes Université, CHU Nantes, Service de Génétique Médicale, Nantes 44000, France
- Nantes Université, CHU Nantes, CNRS, INSERM, l’institut du thorax, Nantes 44000, France
| | - Thomas Besnard
- Nantes Université, CHU Nantes, Service de Génétique Médicale, Nantes 44000, France
- Nantes Université, CHU Nantes, CNRS, INSERM, l’institut du thorax, Nantes 44000, France
| | - Benjamin Cogne
- Nantes Université, CHU Nantes, Service de Génétique Médicale, Nantes 44000, France
- Nantes Université, CHU Nantes, CNRS, INSERM, l’institut du thorax, Nantes 44000, France
| | - Wallid Deb
- Nantes Université, CHU Nantes, Service de Génétique Médicale, Nantes 44000, France
- Nantes Université, CHU Nantes, CNRS, INSERM, l’institut du thorax, Nantes 44000, France
| | - Clotilde Rivier
- Department of Paediatrics, Villefranche-sur-Saône Hospital, Villefranche-sur-Saône 69655, France
| | - Donatella Milani
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Maria Francesca Bedeschi
- Medical Genetics Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Claudia Di Napoli
- Medical Genetics Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Federico Grilli
- Medical Genetics Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Paola Marchisio
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pediatria Pneumoinfettivologia, Milan 20122, Italy
- University of Milan, Milan 20122, Italy
| | - Suzanna Koudijs
- Department of Neurology, ENCORE, Erasmus Medical Center-Sophia Children’s Hospital, Rotterdam 3015, The Netherlands
| | - Danielle Veenma
- Department of Pediatrics, ENCORE, Erasmus Medical Center-Sophia Children’s Hospital, Rotterdam 3015, The Netherlands
| | - Emanuela Argilli
- Institute of Human Genetics, University of California, San Francisco, CA 94143, USA
- Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA 94143, USA
| | - Sally Ann Lynch
- Department of Clinical Genetics, Children’s Health Ireland Crumlin, Dublin D12 N512, Ireland
| | - Ping Yee Billie Au
- Department of Medical Genetics, Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | | | | | - Diane Masser-Frye
- Division of Genetics, Department of Pediatrics, UC San Diego School of Medicine, Rady Children’s Hospital, San Diego, CA 92123, USA
| | - Marilyn Jones
- Division of Genetics, Department of Pediatrics, UC San Diego School of Medicine, Rady Children’s Hospital, San Diego, CA 92123, USA
| | - Leslie Patron Romero
- Facultad de Medicina y Psicología, Universidad Autónoma de Baja California, Tijuana 22010, Mexico
| | | | | | - Laura Hecher
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg 20215, Germany
| | - Jessika Johannsen
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg 20215, Germany
| | - Jonas Denecke
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg 20215, Germany
| | - Vanda McNiven
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1E8, Canada
- Fred A Litwin Family Centre in Genetic Medicine, University Health Network and Mount Sinai Hospital, Toronto, ON M5G 2C4, Canada
| | - Anna Szuto
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1E8, Canada
- Department of Paediatrics, Hospital for Sick Children and University of Toronto, Toronto, ON M5G 1E8, Canada
| | - Emma Wakeling
- North East Thames Regional Genetics Service, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Vincent Cruz
- DDC Clinic Center for Special Needs Children, Middlefield, OH 44062, USA
| | - Valerie Sency
- DDC Clinic Center for Special Needs Children, Middlefield, OH 44062, USA
| | - Heng Wang
- DDC Clinic Center for Special Needs Children, Middlefield, OH 44062, USA
| | - Juliette Piard
- Centre de Génétique Humaine, Centre Hospitalier Universitaire, Université de Franche-Comté, Besançon 25000, France
- UMR 1231 GAD, Inserm, Université de Bourgogne Franche-Comté, Dijon 21000, France
| | - Fanny Kortüm
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany
| | - Theresia Herget
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany
| | - Tatjana Bierhals
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany
| | - Angelo Condell
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria 3052, Australia
| | - Bruria Ben-Zeev
- Pediatric Neurology Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Ramat Gan 52621, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv 4R73+8Q, Israel
| | - Simranpreet Kaur
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria 3052, Australia
- Department of Paediatrics, Melbourne Medical School, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - John Christodoulou
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Melbourne, Victoria 3052, Australia
- Department of Paediatrics, Melbourne Medical School, University of Melbourne, Melbourne, Victoria 3052, Australia
- Discipline of Genetic Medicine, Sydney Medical School, University of Sydney, Sydney, New South Wales 2050, Australia
- Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NewSouth Wales 2050, Australia
| | - Amelie Piton
- Hôpitaux Universitaires de Strasbourg, Laboratoire de Diagnostic Génétique, Strasbourg 67000, France
| | - Christiane Zweier
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
- Department of Human Genetics, Inselspital Bern, University of Bern, Bern 3010, Switzerland
| | - Cornelia Kraus
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - Alessia Micalizzi
- Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, Rome 00165, Italy
| | - Marina Trivisano
- Neurology, Epilepsy and Movement Disorders, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome 00165, Italy
| | - Nicola Specchio
- Neurology, Epilepsy and Movement Disorders, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome 00165, Italy
| | - Gaetan Lesca
- Department of Medical Genetics, University Hospital of Lyon and Claude Bernard Lyon I University, Lyon 69100, France
- Pathophysiology and Genetics of Neuron and Muscle (PNMG), UCBL, CNRS UMR5261 - INSERM U1315, Lyon 69100, France
| | - Rikke S Møller
- Department of Epilepsy Genetics and Personalized Medicine, Danish Epilepsy Centre, Dianalund 4293, Denmark
- Department of Regional Health Research, University of Southern Denmark, Odense 5230Denmark
| | - Zeynep Tümer
- Kennedy Center, Department of Clinical Genetics, Copenhagen University Hospital, Rigshospitalet, Copenhagen 2100, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - Maria Musgaard
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1H 8M5, Canada
| | - Benedicte Gerard
- Laboratoires de diagnostic genetique, Institut de genetique Medicale d'Alsace, Hopitaux Universitaires de Strasbourg, Strasbourg 67000, France
| | - Johannes R Lemke
- Center for Rare Diseases, University of Leipzig Medical Center, Leipzig 04103, Germany
| | - Yun Stone Shi
- State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Department of Neurology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing 210032, China
- Ministry of Education Key Laboratory of Model Animal for Disease Study, National Resource Center for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing 210032, China
- Guangdong Institute of Intelligence Science and Technology, Zhuhai 519031, China
| | - Anders S Kristensen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
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11
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Talucci I, Arlt FA, Kreissner KO, Nasouti M, Wiessler AL, Miske R, Mindorf S, Dettmann I, Moniri M, Bayer M, Broegger Christensen P, Ayzenberg I, Kraft A, Endres M, Komorowski L, Villmann C, Doppler K, Prüss H, Maric HM. Molecular dissection of an immunodominant epitope in K v1.2-exclusive autoimmunity. Front Immunol 2024; 15:1329013. [PMID: 38665908 PMCID: PMC11043588 DOI: 10.3389/fimmu.2024.1329013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/22/2024] [Indexed: 04/28/2024] Open
Abstract
Introduction Subgroups of autoantibodies directed against voltage-gated potassium channel (Kv) complex components have been associated with immunotherapy-responsive clinical syndromes. The high prevalence and the role of autoantibodies directly binding Kv remain, however, controversial. Our objective was to determine Kv autoantibody binding requirements and to clarify their contribution to the observed immune response. Methods Binding epitopes were studied in sera (n = 36) and cerebrospinal fluid (CSF) (n = 12) from a patient cohort positive for Kv1.2 but negative for 32 common neurological autoantigens and controls (sera n = 18 and CSF n = 5) by phospho and deep mutational scans. Autoantibody specificity and contribution to the observed immune response were resolved on recombinant cells, cerebellum slices, and nerve fibers. Results 83% of the patients (30/36) within the studied cohort shared one out of the two major binding epitopes with Kv1.2-3 reactivity. Eleven percent (4/36) of the serum samples showed no binding. Fingerprinting resolved close to identical sequence requirements for both shared epitopes. Kv autoantibody response is directed against juxtaparanodal regions in peripheral nerves and the axon initial segment in central nervous system neurons and exclusively mediated by the shared epitopes. Discussion Systematic mapping revealed two shared autoimmune responses, with one dominant Kv1.2-3 autoantibody epitope being unexpectedly prevalent. The conservation of the molecular binding requirements among these patients indicates a uniform autoantibody repertoire with monospecific reactivity. The enhanced sensitivity of the epitope-based (10/12) compared with that of the cell-based detection (7/12) highlights its use for detection. The determined immunodominant epitope is also the primary immune response visible in tissue, suggesting a diagnostic significance and a specific value for routine screening.
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Affiliation(s)
- Ivan Talucci
- Rudolf Virchow Center for Integrative and Translational Bioimaging; University of Würzburg, Würzburg, Germany
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Friederike A. Arlt
- Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | - Kai O. Kreissner
- Rudolf Virchow Center for Integrative and Translational Bioimaging; University of Würzburg, Würzburg, Germany
| | - Mahoor Nasouti
- Rudolf Virchow Center for Integrative and Translational Bioimaging; University of Würzburg, Würzburg, Germany
- Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Anna-Lena Wiessler
- Institute for Clinical Neurobiology, University of Wuerzburg, Würzburg, Germany
| | - Ramona Miske
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Swantje Mindorf
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Inga Dettmann
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Mehrnaz Moniri
- Rudolf Virchow Center for Integrative and Translational Bioimaging; University of Würzburg, Würzburg, Germany
| | - Markus Bayer
- Rudolf Virchow Center for Integrative and Translational Bioimaging; University of Würzburg, Würzburg, Germany
| | | | - Ilya Ayzenberg
- Department of Neurology, St. Josef-Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Andrea Kraft
- Department of Neurology, Hospital Martha-Maria, Halle, Germany
| | - Matthias Endres
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
- Klinik und Hochschulambulanz für Neurologie, Charité-Universitätsmedizin, Berlin, Germany
- Center for Stroke Research, Berlin, Germany
- German Centre for Cardiovascular Research (DZHK), Berlin, Germany
- German Center for Mental Health (DZPG), Berlin, Germany
| | - Lars Komorowski
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Carmen Villmann
- Institute for Clinical Neurobiology, University of Wuerzburg, Würzburg, Germany
| | - Kathrin Doppler
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Harald Prüss
- Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | - Hans M. Maric
- Rudolf Virchow Center for Integrative and Translational Bioimaging; University of Würzburg, Würzburg, Germany
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12
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Kassabian B, Levy AM, Gardella E, Aledo-Serrano A, Ananth AL, Brea-Fernández AJ, Caumes R, Chatron N, Dainelli A, De Wachter M, Denommé-Pichon AS, Dye TJ, Fazzi E, Felt R, Fernández-Jaén A, Fernández-Prieto M, Gantz E, Gasperowicz P, Gil-Nagel A, Gómez-Andrés D, Greiner HM, Guerrini R, Haanpää MK, Helin M, Hoyer J, Hurst ACE, Kallish S, Karkare SN, Khan A, Kleinendorst L, Koch J, Kothare SV, Koudijs SM, Lagae L, Lakeman P, Leppig KA, Lesca G, Lopergolo D, Lusk L, Mackenzie A, Mei D, Møller RS, Pereira EM, Platzer K, Quelin C, Revah-Politi A, Rheims S, Rodríguez-Palmero A, Rossi A, Santorelli F, Seinfeld S, Sell E, Stephenson D, Szczaluba K, Trinka E, Umair M, Van Esch H, van Haelst MM, Veenma DCM, Weber S, Weckhuysen S, Zacher P, Tümer Z, Rubboli G. Developmental epileptic encephalopathy in DLG4-related synaptopathy. Epilepsia 2024; 65:1029-1045. [PMID: 38135915 DOI: 10.1111/epi.17876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 12/05/2023] [Accepted: 12/20/2023] [Indexed: 12/24/2023]
Abstract
OBJECTIVE The postsynaptic density protein of excitatory neurons PSD-95 is encoded by discs large MAGUK scaffold protein 4 (DLG4), de novo pathogenic variants of which lead to DLG4-related synaptopathy. The major clinical features are developmental delay, intellectual disability (ID), hypotonia, sleep disturbances, movement disorders, and epilepsy. Even though epilepsy is present in 50% of the individuals, it has not been investigated in detail. We describe here the phenotypic spectrum of epilepsy and associated comorbidities in patients with DLG4-related synaptopathy. METHODS We included 35 individuals with a DLG4 variant and epilepsy as part of a multicenter study. The DLG4 variants were detected by the referring laboratories. The degree of ID, hypotonia, developmental delay, and motor disturbances were evaluated by the referring clinician. Data on awake and sleep electroencephalography (EEG) and/or video-polygraphy and brain magnetic resonance imaging were collected. Antiseizure medication response was retrospectively assessed by the referring clinician. RESULTS A large variety of seizure types was reported, although focal seizures were the most common. Encephalopathy related to status epilepticus during slow-wave sleep (ESES)/developmental epileptic encephalopathy with spike-wave activation during sleep (DEE-SWAS) was diagnosed in >25% of the individuals. All but one individual presented with neurodevelopmental delay. Regression in verbal and/or motor domains was observed in all individuals who suffered from ESES/DEE-SWAS, as well as some who did not. We could not identify a clear genotype-phenotype relationship even between individuals with the same DLG4 variants. SIGNIFICANCE Our study shows that a subgroup of individuals with DLG4-related synaptopathy have DEE, and approximately one fourth of them have ESES/DEE-SWAS. Our study confirms DEE as part of the DLG4-related phenotypic spectrum. Occurrence of ESES/DEE-SWAS in DLG4-related synaptopathy requires proper investigation with sleep EEG.
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Affiliation(s)
- Benedetta Kassabian
- Department of Epilepsy Genetics and Precision Medicine, Danish Epilepsy Center Filadelfia, member of the European Reference Network EpiCARE, Dianalund, Denmark
- Neurology Unit, Department of Neurosciences, University of Padua, Padua, Italy
| | - Amanda M Levy
- Department of Clinical Genetics, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Elena Gardella
- Department of Epilepsy Genetics and Precision Medicine, Danish Epilepsy Center Filadelfia, member of the European Reference Network EpiCARE, Dianalund, Denmark
- Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Angel Aledo-Serrano
- Epilepsy and Neurogenetics Unit, Vithas la Milagrosa University Hospital, Vithas Hospital Group, Madrid, Spain
| | - Amitha L Ananth
- Division of Pediatric Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Alejandro J Brea-Fernández
- Grupo de Genómica y Bioinformática, Centro Singular de Investigación en Medicina Molecular y Enfermedades Crónicas (CiMUS), Centro de Investigación Biomédica en Red de Enfermedades Raras del Instituto de Salud Carlos III (CIBERER-ISCIII), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
- Grupo de Genética, Fundación Pública Galega de Medicina Xenómica, Instituto de Investigación Biomédica de Santiago (IDIS), Santiago de Compostela, Spain
| | | | - Nicolas Chatron
- Service de Genetique, Hospices Civils de Lyon, Bron, France
- Institute NeuroMyoGène, Laboratoire Physiopathologie et Génétique du Neurone et du Muscle, Centre National de la recherche scientifique (CNRS) Unité mixte de recherche (UMR) 5261- L'Institut national de la santé et de la recherche médicale (INSERM) U1315, Université de Lyon-Université Claude Bernard Lyon 1, Lyon, France
| | - Alice Dainelli
- Neuroscience Department, Meyer Children's Hospital IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico), member of the European Reference Network EpiCARE, Florence, Italy
| | - Matthias De Wachter
- Department of Pediatric Neurology, Antwerp University Hospital, University of Antwerp, Edegem, Belgium
| | - Anne-Sophie Denommé-Pichon
- Functional Unit for Diagnostic Innovation in Rare Diseases, Fédération Hospitalo-Universitaire Médecine TRANSLationnelle et Anomalies du Développement (FHU-TRANSLAD), Dijon Bourgogne University Hospital, Dijon, France
- L'Institut national de la santé et de la recherche médicale (INSERM) Unité mixte de recherche (UMR) 1231, Génétique des Anomalies du Développement (GAD), Fédération Hospitalo-Universitaire Médecine TRANSLationnelle et Anomalies du Développement (FHU-TRANSLAD), University of Burgundy, Dijon, France
| | - Thomas J Dye
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Elisa Fazzi
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
- Unit of Child Neurology and Psychiatry, Azienda Socio Sanitaria Territoriale (ASST) Spedali Civili of Brescia, Brescia, Italy
| | - Roxanne Felt
- Department of Neurology, Kaiser Permanente Bellevue Medical Center, Bellevue, Washington, USA
| | - Alberto Fernández-Jaén
- Department of Pediatric Neurology, Neurogenetics Section, Hospital Universitario Quirónsalud, Madrid, Spain
- Facultad de Medicina, Universidad Europea, Madrid, Spain
| | - Montse Fernández-Prieto
- Grupo de Genómica y Bioinformática, Centro Singular de Investigación en Medicina Molecular y Enfermedades Crónicas (CiMUS), Centro de Investigación Biomédica en Red de Enfermedades Raras del Instituto de Salud Carlos III (CIBERER-ISCIII), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
- Grupo de Genética, Fundación Pública Galega de Medicina Xenómica, Instituto de Investigación Biomédica de Santiago (IDIS), Santiago de Compostela, Spain
| | - Emily Gantz
- Division of Pediatric Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Piotr Gasperowicz
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Antonio Gil-Nagel
- Neurology Department, Epilepsy Program, Ruber Internacional Hospital, Madrid, Spain
| | - David Gómez-Andrés
- Child Neurology Unit, Hospital Universitari Vall d'Hebron, Vall d'Hebron Research Institute, Barcelona, Spain
| | - Hansel M Greiner
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Renzo Guerrini
- Neuroscience Department, Meyer Children's Hospital IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico), member of the European Reference Network EpiCARE, Florence, Italy
| | - Maria K Haanpää
- Department of Genomics, Turku University Hospital, Turku, Finland
| | - Minttu Helin
- Department of Pediatric Neurology, Turku University Hospital, Turku, Finland
| | - Juliane Hoyer
- Friedrich-Alexander-Universität Erlangen Nürnberg, Institute of Human Genetics, Erlangen, Germany
| | - Anna C E Hurst
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Staci Kallish
- Division of Translational Medicine and Human Genetics, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Shefali N Karkare
- Division of Pediatric Neurology, Department of Pediatrics, Cohen Children's Medical Center, New Hyde Park, New York, USA
| | - Amjad Khan
- Department of Zoology, Faculty of Biological Sciences, University of Lakki Marwat, Lakki Marwat, Pakistan
- Institute for Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Lotte Kleinendorst
- Department of Human Genetics, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, the Netherlands
- Emma Center for Personalized Medicine, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, the Netherlands
| | - Johannes Koch
- University Children's Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Sanjeev V Kothare
- Division of Pediatric Neurology, Department of Pediatrics, Cohen Children's Medical Center, New Hyde Park, New York, USA
| | - Suzanna M Koudijs
- Department of Neurology, Erasmus Medical Center (MC) Sophia Children's Hospital, Rotterdam, the Netherlands
- Erfelijke Neuro-Cognitieve Ontwikkelingsstoornissen, Rotterdam, Erasmus Medical Center (ENCORE)-GRIN Expertise Center, Rotterdam, the Netherlands
| | - Lieven Lagae
- Department of Development and Regeneration, Section Paediatric Neurology, member of the European Reference Network EpiCARE, University Hospitals Leuven, Leuven, Belgium
| | - Phillis Lakeman
- Department of Human Genetics, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, the Netherlands
| | - Kathleen A Leppig
- Genetic Services, Kaiser Permanente of Washington, Seattle, Washington, USA
| | - Gaetan Lesca
- Service de Genetique, Hospices Civils de Lyon, Bron, France
- Institute NeuroMyoGène, Laboratoire Physiopathologie et Génétique du Neurone et du Muscle, Centre National de la recherche scientifique (CNRS) Unité mixte de recherche (UMR) 5261- L'Institut national de la santé et de la recherche médicale (INSERM) U1315, Université de Lyon-Université Claude Bernard Lyon 1, Lyon, France
| | - Diego Lopergolo
- Department of Medicine, Surgery, and Neurosciences, University of Siena, Siena, Italy
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Stella Maris Foundation, Pisa, Italy
| | - Laina Lusk
- Division of Neurology, Epilepsy Neurogenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Alex Mackenzie
- Research Institute, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Davide Mei
- Neuroscience Department, Meyer Children's Hospital IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico), member of the European Reference Network EpiCARE, Florence, Italy
| | - Rikke S Møller
- Department of Epilepsy Genetics and Precision Medicine, Danish Epilepsy Center Filadelfia, member of the European Reference Network EpiCARE, Dianalund, Denmark
- Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Elaine M Pereira
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons and New York-Presbyterian Morgan Stanley Children's Hospital, New York, New York, USA
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Chloe Quelin
- Department of Medical Genetics, CHU de Rennes, Rennes, France
| | - Anya Revah-Politi
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - Sylvain Rheims
- Department of Functional Neurology and Epileptology, member of the European Reference Network EpiCARE, Hospices Civils de Lyon and Lyon 1 University, Lyon, France
| | - Agustí Rodríguez-Palmero
- Paediatric Neurology Unit, Department of Pediatrics, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain
- Grupo de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
| | - Andrea Rossi
- Unit of Child Neurology and Psychiatry, Azienda Socio Sanitaria Territoriale (ASST) Spedali Civili of Brescia, Brescia, Italy
| | - Filippo Santorelli
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Stella Maris Foundation, Pisa, Italy
| | - Syndi Seinfeld
- Department of Pediatric Neurology, Neuroscience Center, Joe DiMaggio Children's Hospital, Hollywood, Florida, USA
| | - Erick Sell
- Division of Neurology, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Donna Stephenson
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Krzysztof Szczaluba
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
- Center of Excellence for Rare and Undiagnosed Diseases, Medical University of Warsaw, Warsaw, Poland
| | - Eugen Trinka
- Department of Neurology, Neurointensive Care and Neurorehabilitation, Christian Doppler University Hospital, member of the European Reference Network EpiCARE, Paracelsus Medical University, Center for Cognitive Neuroscience, Salzburg, Austria
- Neuroscience Institute, Christian Doppler University Hospital, member of the European Reference Network EpiCARE, Paracelsus Medical University, Center for Cognitive Neuroscience, Salzburg, Austria
| | - Muhammad Umair
- Medical Genomics Research Department, King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- Department of Life Sciences, School of Science, University of Management and Technology, Lahore, Pakistan
| | - Hilde Van Esch
- Center for Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - Mieke M van Haelst
- Department of Human Genetics, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, the Netherlands
- Emma Center for Personalized Medicine, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, the Netherlands
| | - Danielle C M Veenma
- Erfelijke Neuro-Cognitieve Ontwikkelingsstoornissen, Rotterdam, Erasmus Medical Center (ENCORE)-GRIN Expertise Center, Rotterdam, the Netherlands
- Department of Pediatrics, Erasmus Medical Center (MC)-Sophia Hospital, Rotterdam, the Netherlands
| | - Sacha Weber
- Service de Génétique, Centre Hospitalier Universitaire (CHU) de Caen-Normandie, Caen, France
- Service de Neurologie, Centre Hospitalier Universitaire (CHU) de Caen-Normandie, Caen, France
| | - Sarah Weckhuysen
- Applied and Translational Neurogenomics Group, Vlaams Instituut voor Biotechnologie (VIB) Center for Molecular Neurology, Antwerp, Belgium
- Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Pia Zacher
- Center for Adults with Disability (MZEB), Epilepsy Center Kleinwachau, Radeberg, Germany
| | - Zeynep Tümer
- Department of Clinical Genetics, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Guido Rubboli
- Department of Epilepsy Genetics and Precision Medicine, Danish Epilepsy Center Filadelfia, member of the European Reference Network EpiCARE, Dianalund, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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13
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DeKorver NW, Zhao W, Butler MR, Di Luca DG, Gurnett C, Nascimento F. An adult with KCNA2-related epilepsy and ataxia. Epileptic Disord 2024; 26:264-266. [PMID: 38366944 DOI: 10.1002/epd2.20205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/19/2024]
Abstract
Content available: Video
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Affiliation(s)
- Nicholas W DeKorver
- Washington University in St Louis Ringgold standard institution - Neurology, St Louis, Missouri, USA
| | - Wei Zhao
- Washington University in St Louis Ringgold standard institution - Neurology, St Louis, Missouri, USA
| | - Michael R Butler
- Washington University in St Louis Ringgold standard institution - Neurology, St Louis, Missouri, USA
| | - Daniel G Di Luca
- Washington University in St Louis Ringgold standard institution - Neurology, St Louis, Missouri, USA
| | - Christina Gurnett
- Washington University in St Louis Ringgold standard institution - Neurology, St Louis, Missouri, USA
| | - Fabio Nascimento
- Washington University in St Louis Ringgold standard institution - Neurology, St Louis, Missouri, USA
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14
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Xie C, Kessi M, Yin F, Peng J. Roles of KCNA2 in Neurological Diseases: from Physiology to Pathology. Mol Neurobiol 2024:10.1007/s12035-024-04120-9. [PMID: 38517617 DOI: 10.1007/s12035-024-04120-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 03/10/2024] [Indexed: 03/24/2024]
Abstract
Potassium voltage-gated channel subfamily a member 2 (Kv1.2, encoded by KCNA2) is highly expressed in the central and peripheral nervous systems. Based on the patch clamp studies, gain-of function (GOF), loss-of-function (LOF), and a mixed type (GOF/LOF) variants can cause different conditions/disorders. KCNA2-related neurological diseases include epilepsy, intellectual disability (ID), attention deficit/hyperactive disorder (ADHD), autism spectrum disorder (ASD), pain as well as autoimmune and movement disorders. Currently, the molecular mechanisms for the reported variants in causing diverse disorders are unknown. Consequently, this review brings up to date the related information regarding the structure and function of Kv1.2 channel, expression patterns, neuronal localizations, and tetramerization as well as important cell and animal models. In addition, it provides updates on human genetic variants, genotype-phenotype correlations especially highlighting the deep insight into clinical prognosis of KCNA2-related developmental and epileptic encephalopathy, mechanisms, and the potential treatment targets for all KCNA2-related neurological disorders.
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Affiliation(s)
- Changning Xie
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Hunan, Changsha, 410008, China
| | - Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Hunan, Changsha, 410008, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Hunan, Changsha, 410008, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Hunan, Changsha, 410008, China.
- Hunan Intellectual and Development Disabilities Research Center, Hunan, Changsha, 410008, China.
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15
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Nikitin ES, Postnikova TY, Proskurina EY, Borodinova AA, Ivanova V, Roshchin MV, Smirnova MP, Kelmanson I, Belousov VV, Balaban PM, Zaitsev AV. Overexpression of KCNN4 channels in principal neurons produces an anti-seizure effect without reducing their coding ability. Gene Ther 2024; 31:144-153. [PMID: 37968509 DOI: 10.1038/s41434-023-00427-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 10/13/2023] [Accepted: 10/24/2023] [Indexed: 11/17/2023]
Abstract
Gene therapy offers a potential alternative to the surgical treatment of epilepsy, which affects millions of people and is pharmacoresistant in ~30% of cases. Aimed at reducing the excitability of principal neurons, the engineered expression of K+ channels has been proposed as a treatment due to the outstanding ability of K+ channels to hyperpolarize neurons. However, the effects of K+ channel overexpression on cell physiology remain to be investigated. Here we report an adeno-associated virus (AAV) vector designed to reduce epileptiform activity specifically in excitatory pyramidal neurons by expressing the human Ca2+-gated K+ channel KCNN4 (KCa3.1). Electrophysiological and pharmacological experiments in acute brain slices showed that KCNN4-transduced cells exhibited a Ca2+-dependent slow afterhyperpolarization that significantly decreased the ability of KCNN4-positive neurons to generate high-frequency spike trains without affecting their lower-frequency coding ability and action potential shapes. Antiepileptic activity tests showed potent suppression of pharmacologically induced seizures in vitro at both single cell and local field potential levels with decreased spiking during ictal discharges. Taken together, our findings strongly suggest that the AAV-based expression of the KCNN4 channel in excitatory neurons is a promising therapeutic intervention as gene therapy for epilepsy.
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Affiliation(s)
- Evgeny S Nikitin
- Institute of Higher Nervous Activity and Neurophysiology, RAS, 117485, Moscow, Russia.
| | - Tatiana Y Postnikova
- Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, Saint Petersburg, Russia
| | - Elena Y Proskurina
- Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, Saint Petersburg, Russia
| | | | - Violetta Ivanova
- Institute of Higher Nervous Activity and Neurophysiology, RAS, 117485, Moscow, Russia
| | - Matvey V Roshchin
- Institute of Higher Nervous Activity and Neurophysiology, RAS, 117485, Moscow, Russia
| | - Maria P Smirnova
- Institute of Higher Nervous Activity and Neurophysiology, RAS, 117485, Moscow, Russia
| | - Ilya Kelmanson
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, 117997, Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997, Moscow, Russia
| | - Vsevolod V Belousov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, 117997, Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997, Moscow, Russia
- Federal Center of Brain Research and Neurotechnologies, Federal Medical Biological Agency, 117997, Moscow, Russia
- Life Improvement by Future Technologies (LIFT) Center, 143025, Moscow, Russia
| | - Pavel M Balaban
- Institute of Higher Nervous Activity and Neurophysiology, RAS, 117485, Moscow, Russia
| | - Aleksey V Zaitsev
- Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, Saint Petersburg, Russia.
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16
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Arlt FA, Miske R, Machule ML, Broegger Christensen P, Mindorf S, Teegen B, Borowski K, Buthut M, Rößling R, Sánchez-Sendín E, van Hoof S, Cordero-Gómez C, Bünger I, Radbruch H, Kraft A, Ayzenberg I, Klausewitz J, Hansen N, Timäus C, Körtvelyessy P, Postert T, Baur-Seack K, Rost C, Brunkhorst R, Doppler K, Haigis N, Hamann G, Kunze A, Stützer A, Maschke M, Melzer N, Rosenow F, Siebenbrodt K, Stenør C, Dichgans M, Georgakis MK, Fang R, Petzold GC, Görtler M, Zerr I, Wunderlich S, Mihaljevic I, Turko P, Schmidt Ettrup M, Buchholz E, Foverskov Rasmussen H, Nasouti M, Talucci I, Maric HM, Heinemann SH, Endres M, Komorowski L, Prüss H. KCNA2 IgG autoimmunity in neuropsychiatric diseases. Brain Behav Immun 2024; 117:399-411. [PMID: 38309639 DOI: 10.1016/j.bbi.2024.01.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/04/2024] [Accepted: 01/25/2024] [Indexed: 02/05/2024] Open
Abstract
BACKGROUND Autoantibodies against the potassium voltage-gated channel subfamily A member 2 (KCNA2) have been described in a few cases of neuropsychiatric disorders, but their diagnostic and pathophysiological role is currently unknown, imposing challenges to medical practice. DESIGN / METHODS We retrospectively collected comprehensive clinical and paraclinical data of 35 patients with KCNA2 IgG autoantibodies detected in cell-based and tissue-based assays. Patients' sera and cerebrospinal fluid (CSF) were used for characterization of the antigen, clinical-serological correlations, and determination of IgG subclasses. RESULTS KCNA2 autoantibody-positive patients (n = 35, median age at disease onset of 65 years, range of 16-83 years, 74 % male) mostly presented with cognitive impairment and/or epileptic seizures but also ataxia, gait disorder and personality changes. Serum autoantibodies belonged to IgG3 and IgG1 subclasses and titers ranged from 1:32 to 1:10,000. KCNA2 IgG was found in the CSF of 8/21 (38 %) patients and in the serum of 4/96 (4.2 %) healthy blood donors. KCNA2 autoantibodies bound to characteristic anatomical areas in the cerebellum and hippocampus of mammalian brain and juxtaparanodal regions of peripheral nerves but reacted exclusively with intracellular epitopes. A subset of four KCNA2 autoantibody-positive patients responded markedly to immunotherapy alongside with conversion to seronegativity, in particular those presenting an autoimmune encephalitis phenotype and receiving early immunotherapy. An available brain biopsy showed strong immune cell invasion. KCNA2 autoantibodies occurred in less than 10 % in association with an underlying tumor. CONCLUSION Our data suggest that KCNA2 autoimmunity is clinically heterogeneous. Future studies should determine whether KCNA2 autoantibodies are directly pathogenic or develop secondarily. Early immunotherapy should be considered, in particular if autoantibodies occur in CSF or if clinical or diagnostic findings suggest ongoing inflammation. Suspicious clinical phenotypes include autoimmune encephalitis, atypical dementia, new-onset epilepsy and unexplained epileptic seizures.
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Affiliation(s)
- Friederike A Arlt
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Ramona Miske
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Marie-Luise Machule
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | | | - Swantje Mindorf
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Bianca Teegen
- Clinical immunological Laboratory Prof. Stöcker, Groß Grönau, Germany
| | - Kathrin Borowski
- Clinical immunological Laboratory Prof. Stöcker, Groß Grönau, Germany
| | - Maria Buthut
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany; Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Rosa Rößling
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Elisa Sánchez-Sendín
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Scott van Hoof
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - César Cordero-Gómez
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Isabel Bünger
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Helena Radbruch
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Andrea Kraft
- Department of Neurology, Hospital Martha-Maria, Halle, Germany
| | - Ilya Ayzenberg
- Department of Neurology, St Josef-Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jaqueline Klausewitz
- Department of Neurology, St Josef-Hospital, Ruhr University Bochum, Bochum, Germany
| | - Niels Hansen
- Department of Psychiatry and Psychotherapy, University Göttingen Medical Center, Göttingen, Germany
| | - Charles Timäus
- Department of Psychiatry and Psychotherapy, University Göttingen Medical Center, Göttingen, Germany
| | - Peter Körtvelyessy
- Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Magdeburg, Germany
| | - Thomas Postert
- Department of Neurology, St. Vincenz-Krankenhaus Paderborn, Paderborn, Germany
| | - Kirsten Baur-Seack
- Department of Neurology, St. Vincenz-Krankenhaus Paderborn, Paderborn, Germany
| | - Constanze Rost
- Department of Neurology, St. Vincenz-Krankenhaus Paderborn, Paderborn, Germany
| | - Robert Brunkhorst
- Department of Neurology, University Hospital Aachen, Aachen, Germany
| | - Kathrin Doppler
- Department of Neurology, University of Würzburg, Würzburg, Germany
| | - Niklas Haigis
- Department of Child and Adolescent Psychiatry, Centre for Psychosocial Medicine, University of Heidelberg, Heidelberg, Germany
| | - Gerhard Hamann
- Department of Neurology and Neurological Rehabilitation, BKH Günzburg, Günzburg, Germany
| | - Albrecht Kunze
- Department of Neurology, Zentralklinik Bad Berka, Bad Berka, Germany
| | - Alexandra Stützer
- Department of Neurology, Zentralklinik Bad Berka, Bad Berka, Germany
| | - Matthias Maschke
- Department of Neurology, Campus Trier, University of Mainz, Trier, Germany
| | - Nico Melzer
- Department of Neurology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Felix Rosenow
- Epilepsy Center Frankfurt Rhine-Main, Department of Neurology, Goethe University Frankfurt, Frankfurt on the Main, Germany; LOEWE Center for Personalized Translational Epilepsy Research (CePTER), Goethe University, Frankfurt, Germany
| | - Kai Siebenbrodt
- Epilepsy Center Frankfurt Rhine-Main, Department of Neurology, Goethe University Frankfurt, Frankfurt on the Main, Germany; LOEWE Center for Personalized Translational Epilepsy Research (CePTER), Goethe University, Frankfurt, Germany
| | - Christian Stenør
- Department of Neurology, Copenhagen University Hospital, Herlev-Gentofte, Denmark
| | - Martin Dichgans
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany; German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
| | - Marios K Georgakis
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Rong Fang
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Gabor C Petzold
- German Center for Neurodegenerative Diseases (DZNE) Bonn, Bonn, Germany; Division of Vascular Neurology, Department of Neurology, University Hospital Bonn, Bonn, Germany
| | - Michael Görtler
- German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Magdeburg, Germany; Department of Neurology, University Hospital, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Inga Zerr
- German Center for Neurodegenerative Diseases (DZNE) Göttingen, Göttingen, Germany; Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Silke Wunderlich
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich, Germany
| | | | - Paul Turko
- Institute for Integrative Neuroanatomy, Charité-Universitätsmedizin, Berlin, Germany
| | | | - Emilie Buchholz
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Helle Foverskov Rasmussen
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Mahoor Nasouti
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany
| | - Ivan Talucci
- Department of Neurology, University of Würzburg, Würzburg, Germany; Rudolf Virchow Center, Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Hans M Maric
- Rudolf Virchow Center, Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Stefan H Heinemann
- Friedrich Schiller University and Jena University Hospital, Center for Molecular Biomedicine, Department of Biophysics, Jena, Germany
| | - Matthias Endres
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany; Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Lars Komorowski
- Institute for Experimental Immunology, affiliated to EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany
| | - Harald Prüss
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, Berlin, Germany.
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Soldovieri MV, Ambrosino P, Mosca I, Servettini I, Pietrunti F, Belperio G, Syrbe S, Taglialatela M, Lemke JR. De novo variants in KCNA3 cause developmental and epileptic encephalopathy. Ann Neurol 2024; 95:365-376. [PMID: 37964487 DOI: 10.1002/ana.26826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 10/06/2023] [Accepted: 10/23/2023] [Indexed: 11/16/2023]
Abstract
OBJECTIVE Variants in several potassium channel genes, including KCNA1 and KCNA2, cause Developmental and Epileptic Encephalopathies (DEEs). We investigated whether variants in KCNA3, another mammalian homologue of the Drosophila shaker family and encoding for Kv1.3 subunits, can cause DEE. METHODS Genetic analysis of study individuals was performed by routine exome or genome sequencing, usually of parent-offspring trios. Phenotyping was performed via a standard clinical questionnaire. Currents from wild-type and/or mutant Kv1.3 subunits were investigated by whole-cell patch-clamp upon their heterologous expression. RESULTS Fourteen individuals, each carrying a de novo heterozygous missense variant in KCNA3, were identified. Most (12/14; 86%) had DEE with marked speech delay with or without motor delay, intellectual disability, epilepsy, and autism spectrum disorder. Functional analysis of Kv1.3 channels carrying each variant revealed heterogeneous functional changes, ranging from "pure" loss-of-function (LoF) effects due to faster inactivation kinetics, depolarized voltage-dependence of activation, slower activation kinetics, increased current inactivation, reduced or absent currents with or without dominant-negative effects, to "mixed" loss- and gain-of-function (GoF) effects. Compared to controls, Kv1.3 currents in lymphoblasts from 1 of the proband displayed functional changes similar to those observed upon heterologous expression of channels carrying the same variant. The antidepressant drug fluoxetine inhibited with similar potency the currents from wild-type and 1 of the Kv1.3 GoF variant. INTERPRETATION We describe a novel association of de novo missense variants in KCNA3 with a human DEE, and provide evidence that fluoxetine might represent a potential targeted treatment for individuals carrying variants with significant GoF effects. ANN NEUROL 2024;95:365-376.
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Affiliation(s)
| | - Paolo Ambrosino
- Department of Science and Technology, University of Sannio, Benevento, Italy
| | - Ilaria Mosca
- Department of Medicine and Health Science "V. Tiberio", University of Molise, Campobasso, Italy
| | - Ilenio Servettini
- Department of Medicine and Health Science "V. Tiberio", University of Molise, Campobasso, Italy
| | - Francesca Pietrunti
- Department of Medicine and Health Science "V. Tiberio", University of Molise, Campobasso, Italy
| | - Giorgio Belperio
- Department of Science and Technology, University of Sannio, Benevento, Italy
| | - Steffen Syrbe
- Center for Pediatrics and Adolescent Medicine, Division of Pediatric Epileptology, University Hospital Heidelberg, Heidelberg, Germany
| | - Maurizio Taglialatela
- Department of Neuroscience, Division of Pharmacology, University of Naples "Federico II", Naples, Italy
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
- Center for Rare Diseases, University of Leipzig Medical Center, Leipzig, Germany
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18
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Miyazaki Y, Otsuka T, Yamagata Y, Endo T, Sanbo M, Sano H, Kobayashi K, Inahashi H, Kornau HC, Schmitz D, Prüss H, Meijer D, Hirabayashi M, Fukata Y, Fukata M. Oligodendrocyte-derived LGI3 and its receptor ADAM23 organize juxtaparanodal Kv1 channel clustering for short-term synaptic plasticity. Cell Rep 2024; 43:113634. [PMID: 38194969 PMCID: PMC10828548 DOI: 10.1016/j.celrep.2023.113634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/31/2023] [Accepted: 12/14/2023] [Indexed: 01/11/2024] Open
Abstract
Neurodevelopmental disorders, such as intellectual disability (ID), epilepsy, and autism, involve altered synaptic transmission and plasticity. Functional characterization of their associated genes is vital for understanding physio-pathological brain functions. LGI3 is a recently recognized ID-associated gene encoding a secretory protein related to an epilepsy-gene product, LGI1. Here, we find that LGI3 is uniquely secreted from oligodendrocytes in the brain and enriched at juxtaparanodes of myelinated axons, forming nanoscale subclusters. Proteomic analysis using epitope-tagged Lgi3 knockin mice shows that LGI3 uses ADAM23 as a receptor and selectively co-assembles with Kv1 channels. A lack of Lgi3 in mice disrupts juxtaparanodal clustering of ADAM23 and Kv1 channels and suppresses Kv1-channel-mediated short-term synaptic plasticity. Collectively, this study identifies an extracellular organizer of juxtaparanodal Kv1 channel clustering for finely tuned synaptic transmission. Given the defective secretion of the LGI3 missense variant, we propose a molecular pathway, the juxtaparanodal LGI3-ADAM23-Kv1 channel, for understanding neurodevelopmental disorders.
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Affiliation(s)
- Yuri Miyazaki
- Division of Neuropharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan; Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Takeshi Otsuka
- Section of Cellular Electrophysiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan
| | - Yoko Yamagata
- Section of Multilayer Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | | | - Makoto Sanbo
- Section of Mammalian Transgenesis, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Hiromi Sano
- Division of Behavioral Neuropharmacology, International Center for Brain Science, Fujita Health University, Toyoake, Aichi 470-1192, Japan
| | - Kenta Kobayashi
- Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan; Section of Viral Vector Development, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | - Hiroki Inahashi
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Hans-Christian Kornau
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Neuroscience Research Center (NWFZ), Cluster NeuroCure, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dietmar Schmitz
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Neuroscience Research Center (NWFZ), Cluster NeuroCure, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Harald Prüss
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Helmholtz Innovation Lab BaoBab (Brain Antibody-omics and B-cell Lab), Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dies Meijer
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, UK
| | - Masumi Hirabayashi
- Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan; Section of Mammalian Transgenesis, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Yuko Fukata
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Division of Molecular and Cellular Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
| | - Masaki Fukata
- Division of Neuropharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan; Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan.
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19
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Boleti APDA, Cardoso PHDO, Frihling BEF, de Moraes LFRN, Nunes EAC, Mukoyama LTH, Nunes EAC, Carvalho CME, Macedo MLR, Migliolo L. Pathophysiology to Risk Factor and Therapeutics to Treatment Strategies on Epilepsy. Brain Sci 2024; 14:71. [PMID: 38248286 PMCID: PMC10813806 DOI: 10.3390/brainsci14010071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 12/30/2023] [Accepted: 01/06/2024] [Indexed: 01/23/2024] Open
Abstract
Epilepsy represents a condition in which abnormal neuronal discharges or the hyperexcitability of neurons occur with synchronicity, presenting a significant public health challenge. Prognostic factors, such as etiology, electroencephalogram (EEG) abnormalities, the type and number of seizures before treatment, as well as the initial unsatisfactory effects of medications, are important considerations. Although there are several third-generation antiepileptic drugs currently available, their multiple side effects can negatively affect patient quality of life. The inheritance and etiology of epilepsy are complex, involving multiple underlying genetic and epigenetic mechanisms. Different neurotransmitters play crucial roles in maintaining the normal physiology of different neurons. Dysregulations in neurotransmission, due to abnormal transmitter levels or changes in their receptors, can result in seizures. In this review, we address the roles played by various neurotransmitters and their receptors in the pathophysiology of epilepsy. Furthermore, we extensively explore the neurological mechanisms involved in the development and progression of epilepsy, along with its risk factors. Furthermore, we highlight the new therapeutic targets, along with pharmacological and non-pharmacological strategies currently employed in the treatment of epileptic syndromes, including drug interventions employed in clinical trials related to epilepsy.
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Affiliation(s)
- Ana Paula de Araújo Boleti
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
- Laboratório de Purificação de Proteínas e Suas Funções Biológicas, Unidade de Tecnologia de Alimentos e da Saúde Pública, Universidade Federal de Mato Grosso do Sul, Campo Grande 79070-900, Brazil;
| | - Pedro Henrique de Oliveira Cardoso
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
| | - Breno Emanuel Farias Frihling
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
| | - Luiz Filipe Ramalho Nunes de Moraes
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
| | - Ellynes Amancio Correia Nunes
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
- Programa de Pós-graduação em Bioquímica, Universidade Federal do Rio Grande do Norte, Natal 59078-970, Brazil
| | - Lincoln Takashi Hota Mukoyama
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
| | - Ellydberto Amancio Correia Nunes
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
- Programa de Pós-graduação em Bioquímica, Universidade Federal do Rio Grande do Norte, Natal 59078-970, Brazil
| | - Cristiano Marcelo Espinola Carvalho
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
| | - Maria Lígia Rodrigues Macedo
- Laboratório de Purificação de Proteínas e Suas Funções Biológicas, Unidade de Tecnologia de Alimentos e da Saúde Pública, Universidade Federal de Mato Grosso do Sul, Campo Grande 79070-900, Brazil;
| | - Ludovico Migliolo
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, Brazil; (A.P.d.A.B.); (P.H.d.O.C.); (B.E.F.F.); (L.F.R.N.d.M.); (E.A.C.N.); (L.T.H.M.); (E.A.C.N.); (C.M.E.C.)
- Programa de Pós-graduação em Bioquímica, Universidade Federal do Rio Grande do Norte, Natal 59078-970, Brazil
- Programa de Pós-graduação em Biologia Celular e Molecular, Universidade Federal da Paraíba, João Pessoa 58051-900, Brazil
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20
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Khan R, Chaturvedi P, Sahu P, Ludhiadch A, Singh P, Singh G, Munshi A. Role of Potassium Ion Channels in Epilepsy: Focus on Current Therapeutic Strategies. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2024; 23:67-87. [PMID: 36578258 DOI: 10.2174/1871527322666221227112621] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 11/10/2022] [Accepted: 11/12/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND Epilepsy is one of the prevalent neurological disorders characterized by disrupted synchronization between inhibitory and excitatory neurons. Disturbed membrane potential due to abnormal regulation of neurotransmitters and ion transport across the neural cell membrane significantly contributes to the pathophysiology of epilepsy. Potassium ion channels (KCN) regulate the resting membrane potential and are involved in neuronal excitability. Genetic alterations in the potassium ion channels (KCN) have been reported to result in the enhancement of the release of neurotransmitters, the excitability of neurons, and abnormal rapid firing rate, which lead to epileptic phenotypes, making these ion channels a potential therapeutic target for epilepsy. The aim of this study is to explore the variations reported in different classes of potassium ion channels (KCN) in epilepsy patients, their functional evaluation, and therapeutic strategies to treat epilepsy targeting KCN. METHODOLOGY A review of all the relevant literature was carried out to compile this article. RESULTS A large number of variations have been reported in different genes encoding various classes of KCN. These genetic alterations in KCN have been shown to be responsible for disrupted firing properties of neurons. Antiepileptic drugs (AEDs) are the main therapeutic strategy to treat epilepsy. Some patients do not respond favorably to the AEDs treatment, resulting in pharmacoresistant epilepsy. CONCLUSION Further to address the challenges faced in treating epilepsy, recent approaches like optogenetics, chemogenetics, and genome editing, such as clustered regularly interspaced short palindromic repeats (CRISPR), are emerging as target-specific therapeutic strategies.
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Affiliation(s)
- Rahul Khan
- Department of Human Genetics and Molecular Medicine Central University of Punjab, Bathinda 151401, India
| | - Pragya Chaturvedi
- Department of Human Genetics and Molecular Medicine Central University of Punjab, Bathinda 151401, India
| | - Prachi Sahu
- Department of Human Genetics and Molecular Medicine Central University of Punjab, Bathinda 151401, India
| | - Abhilash Ludhiadch
- Department of Human Genetics and Molecular Medicine Central University of Punjab, Bathinda 151401, India
| | - Paramdeep Singh
- Department of Radiology, All India Institute of Medical Sciences, Bathinda, Punjab, 151001 India
| | - Gagandeep Singh
- Department of Neurology, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
| | - Anjana Munshi
- Department of Human Genetics and Molecular Medicine Central University of Punjab, Bathinda 151401, India
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21
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Mínguez-Viñas T, Prakash V, Wang K, Lindström SH, Pozzi S, Scott SA, Spiteri E, Stevenson DA, Ashley EA, Gunnarsson C, Pantazis A. Two epilepsy-associated variants in KCNA2 (K V 1.2) at position H310 oppositely affect channel functional expression. J Physiol 2023; 601:5367-5389. [PMID: 37883018 DOI: 10.1113/jp285052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 10/11/2023] [Indexed: 10/27/2023] Open
Abstract
Two KCNA2 variants (p.H310Y and p.H310R) were discovered in paediatric patients with epilepsy and developmental delay. KCNA2 encodes KV 1.2-channel subunits, which regulate neuronal excitability. Both gain and loss of KV 1.2 function cause epilepsy, precluding the prediction of variant effects; and while H310 is conserved throughout the KV -channel superfamily, it is largely understudied. We investigated both variants in heterologously expressed, human KV 1.2 channels by immunocytochemistry, electrophysiology and voltage-clamp fluorometry. Despite affecting the same channel, at the same position, and being associated with severe neurological disease, the two variants had diametrically opposite effects on KV 1.2 functional expression. The p.H310Y variant produced 'dual gain of function', increasing both cell-surface trafficking and activity, delaying channel closure. We found that the latter is due to the formation of a hydrogen bond that stabilizes the active state of the voltage-sensor domain. Additionally, H310Y abolished 'ball and chain' inactivation of KV 1.2 by KV β1 subunits, enhancing gain of function. In contrast, p.H310R caused 'dual loss of function', diminishing surface levels by multiple impediments to trafficking and inhibiting voltage-dependent channel opening. We discuss the implications for KV -channel biogenesis and function, an emergent hotspot for disease-associated variants, and mechanisms of epileptogenesis. KEY POINTS: KCNA2 encodes the subunits of KV 1.2 voltage-activated, K+ -selective ion channels, which regulate electrical signalling in neurons. We characterize two KCNA2 variants from patients with developmental delay and epilepsy. Both variants affect position H310, highly conserved in KV channels. The p.H310Y variant caused 'dual gain of function', increasing both KV 1.2-channel activity and the number of KV 1.2 subunits on the cell surface. H310Y abolished 'ball and chain' (N-type) inactivation of KV 1.2 by KV β1 subunits, enhancing the gain-of-function phenotype. The p.H310R variant caused 'dual loss of function', diminishing the presence of KV 1.2 subunits on the cell surface and inhibiting voltage-dependent channel opening. As H310Y stabilizes the voltage-sensor active conformation and abolishes N-type inactivation, it can serve as an investigative tool for functional and pharmacological studies.
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Affiliation(s)
- Teresa Mínguez-Viñas
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Varsha Prakash
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Kaiqian Wang
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Sarah H Lindström
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Serena Pozzi
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Stuart A Scott
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - Elizabeth Spiteri
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - David A Stevenson
- Division of Medical Genetics, Stanford University, Palo Alto, California, USA
| | - Euan A Ashley
- Division of Medical Genetics, Stanford University, Palo Alto, California, USA
| | - Cecilia Gunnarsson
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Department of Clinical Genetics, Linköping University, Linköping, Sweden
- Centre for Rare Diseases in South East Region of Sweden, Linköping University, Linköping, Sweden
| | - Antonios Pantazis
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Wallenberg Center for Molecular Medicine, Linköping University, Linköping, Sweden
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22
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Marchesi VT. Impaired electrical activity of the brain explains the onset of dementia in aging people. FASEB J 2023; 37:e23249. [PMID: 37823210 DOI: 10.1096/fj.202301255rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/13/2023]
Abstract
Aging brains that share many cognitive deficits with the early stages of Alzheimer's-type dementias are not caused by toxic protein deposits but by somatic mutations that impair synaptic signaling. These mutant proteins that contribute to neuronal action potentials could be biomarkers of functional defects that offer new approaches to diagnosis and treatment.
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23
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Shakeel K, Olamendi-Portugal T, Naseem MU, Becerril B, Zamudio FZ, Delgado-Prudencio G, Possani LD, Panyi G. Of Seven New K + Channel Inhibitor Peptides of Centruroides bonito, α-KTx 2.24 Has a Picomolar Affinity for Kv1.2. Toxins (Basel) 2023; 15:506. [PMID: 37624263 PMCID: PMC10467108 DOI: 10.3390/toxins15080506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 08/07/2023] [Accepted: 08/11/2023] [Indexed: 08/26/2023] Open
Abstract
Seven new peptides denominated CboK1 to CboK7 were isolated from the venom of the Mexican scorpion Centruroides bonito and their primary structures were determined. The molecular weights ranged between 3760.4 Da and 4357.9 Da, containing 32 to 39 amino acid residues with three putative disulfide bridges. The comparison of amino acid sequences with known potassium scorpion toxins (KTx) and phylogenetic analysis revealed that CboK1 (α-KTx 10.5) and CboK2 (α-KTx 10.6) belong to the α-KTx 10.x subfamily, whereas CboK3 (α-KTx 2.22), CboK4 (α-KTx 2.23), CboK6 (α-KTx 2.21), and CboK7 (α-KTx 2.24) bear > 95% amino acid similarity with members of the α-KTx 2.x subfamily, and CboK5 is identical to Ce3 toxin (α-KTx 2.10). Electrophysiological assays demonstrated that except CboK1, all six other peptides blocked the Kv1.2 channel with Kd values in the picomolar range (24-763 pM) and inhibited the Kv1.3 channel with comparatively less potency (Kd values between 20-171 nM). CboK3 and CboK4 inhibited less than 10% and CboK7 inhibited about 42% of Kv1.1 currents at 100 nM concentration. Among all, CboK7 showed out-standing affinity for Kv1.2 (Kd = 24 pM), as well as high selectivity over Kv1.3 (850-fold) and Kv1.1 (~6000-fold). These characteristics of CboK7 may provide a framework for developing tools to treat Kv1.2-related channelopathies.
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Affiliation(s)
- Kashmala Shakeel
- Department of Biophysics and Cell Biology, Faculty of Medicine, Research Center for Molecular Medicine, University of Debrecen, Egyetem ter. 1, 4032 Debrecen, Hungary; (K.S.); (M.U.N.)
| | - Timoteo Olamendi-Portugal
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnologia, Universidad Nacional Autónoma de México, Av. Universidad 2001, Cuernavaca 62210, Mexico; (T.O.-P.); (B.B.); (F.Z.Z.); (G.D.-P.)
| | - Muhammad Umair Naseem
- Department of Biophysics and Cell Biology, Faculty of Medicine, Research Center for Molecular Medicine, University of Debrecen, Egyetem ter. 1, 4032 Debrecen, Hungary; (K.S.); (M.U.N.)
| | - Baltazar Becerril
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnologia, Universidad Nacional Autónoma de México, Av. Universidad 2001, Cuernavaca 62210, Mexico; (T.O.-P.); (B.B.); (F.Z.Z.); (G.D.-P.)
| | - Fernando Z. Zamudio
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnologia, Universidad Nacional Autónoma de México, Av. Universidad 2001, Cuernavaca 62210, Mexico; (T.O.-P.); (B.B.); (F.Z.Z.); (G.D.-P.)
| | - Gustavo Delgado-Prudencio
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnologia, Universidad Nacional Autónoma de México, Av. Universidad 2001, Cuernavaca 62210, Mexico; (T.O.-P.); (B.B.); (F.Z.Z.); (G.D.-P.)
| | - Lourival Domingos Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnologia, Universidad Nacional Autónoma de México, Av. Universidad 2001, Cuernavaca 62210, Mexico; (T.O.-P.); (B.B.); (F.Z.Z.); (G.D.-P.)
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, Research Center for Molecular Medicine, University of Debrecen, Egyetem ter. 1, 4032 Debrecen, Hungary; (K.S.); (M.U.N.)
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24
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Zhao X, Ding W, Wang H, Wang Y, Liu Y, Li Y, Liu C. Permeability enhancement of Kv1.2 potassium channel by a terahertz electromagnetic field. J Chem Phys 2023; 159:045101. [PMID: 37486058 DOI: 10.1063/5.0143648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 07/03/2023] [Indexed: 07/25/2023] Open
Abstract
As biomolecules vibrate and rotate in the terahertz band, the biological effects of terahertz electromagnetic fields have drawn considerable attention from the physiological and medical communities. Ion channels are the basis of biological electrical signals, so studying the effect of terahertz electromagnetic fields on ion channels is significant. In this paper, the effect of a terahertz electromagnetic field with three different frequencies, 6, 15, and 25 THz, on the Kv1.2 potassium ion channel was investigated by molecular dynamics simulations. The results show that an electromagnetic field with a 15 THz frequency can significantly enhance the permeability of the Kv1.2 potassium ion channel, which is 1.7 times higher than without an applied electric field. By analyzing the behavior of water molecules, it is found that the electromagnetic field with the 15 THz frequency shortens the duration of frozen and relaxation processes when potassium ions pass through the channel, increases the proportion of the direct knock-on mode, and, thus, enhances the permeability of the Kv1.2 potassium ion channel.
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Affiliation(s)
- Xiaofei Zhao
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Wen Ding
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Hongguang Wang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Yize Wang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Yanjiang Liu
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Yongdong Li
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Chunliang Liu
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
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25
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Freibauer AE, RamachandranNair R, Jain P, Jones KC, Whitney R. The genetic landscape of developmental and epileptic encephalopathy with spike-and-wave activation in sleep. Seizure 2023; 110:119-125. [PMID: 37352690 DOI: 10.1016/j.seizure.2023.06.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/13/2023] [Accepted: 06/19/2023] [Indexed: 06/25/2023] Open
Abstract
OBJECTIVE Epileptic Encephalopathy / Developmental Epileptic Encephalopathy with spike-and-wave activation in sleep (EE/DEE-SWAS) is defined as an epilepsy syndrome characterized by neurodevelopmental regression temporally related to the emergence of significant activation of spike-wave discharges in EEG during sleep. The availability of genetic testing has made it evident that monogenic and chromosomal abnormalities play an aetiological role in the development of EE/DEE-SWAS. We sought to review the literature to better understand the genetic landscape of EE/DEE-SWAS. METHODS In this systematic review, we reviewed cases of EE/DEE-SWAS associated with a genetic aetiology, collecting information related to the underlying aetiology, onset, management, and EEG patterns. RESULTS One hundred and seventy-two cases of EE/DEE-SWAS were identified. Genetic causes of note included pathogenic variants in GRIN2A, ZEB2, CNKSR2 and chromosome 17q21.31 deletions, each of which demonstrated unique clinical characteristics, EEG patterns, and age of onset. Factors identified to raise suspicion of a potential genetic aetiology included the presentation of DEE-SWAS and onset of SWAS under the age of five years. Treatment of EE/DEE-SWAS due to genetic causes was diverse, including a combination of anti-seizure medications, steroids, and other clinical strategies, with no clear consensus on a preferred or superior treatment. Data collected was significantly heterogeneous, with a lack of consistent use of neuropsychology testing, EEG patterns, or use of established clinical definitions. CONCLUSIONS Uniformity concerning the new definition of EE/DEE-SWAS, guidelines for management and more frequent genetic screening will be needed to guide best practices for the treatment of patients with EE/DEE-SWAS.
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Affiliation(s)
- Alexander E Freibauer
- Division of Neurology, Department of Paediatrics, McMaster University, Hamilton, ON, Canada
| | | | - Puneet Jain
- Epilepsy Program, Division of Neurology, Department of Paediatrics, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Kevin C Jones
- Division of Neurology, Department of Paediatrics, McMaster University, Hamilton, ON, Canada
| | - Robyn Whitney
- Division of Neurology, Department of Paediatrics, McMaster University, Hamilton, ON, Canada.
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26
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Ding W, Zhao X, Wang H, Wang Y, Liu Y, Gong L, Lin S, Liu C, Li Y. Effect of Terahertz Electromagnetic Field on the Permeability of Potassium Channel Kv1.2. Int J Mol Sci 2023; 24:10271. [PMID: 37373419 DOI: 10.3390/ijms241210271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/10/2023] [Accepted: 06/15/2023] [Indexed: 06/29/2023] Open
Abstract
In this paper, the influence of external terahertz electromagnetic fields with different frequencies of 4 THz, 10 THz, 15 THz, and 20 THz on the permeability of the Kv1.2 voltage-gated potassium ion channel on the nerve cell membrane was studied using the combined model of the "Constant Electric Field-Ion Imbalance" method by molecular dynamics. We found that although the applied terahertz electric field does not produce strong resonance with the -C=O groups of the conservative sequence T-V-G-Y-G amino acid residue of the selective filter (SF) of the channel, it would affect the stability of the electrostatic bond between potassium ions and the carbonyl group of T-V-G-Y-G of SF, and it would affect the stability of the hydrogen bond between water molecules and oxygen atoms of the hydroxyl group of the 374THR side chain at the SF entrance, changing the potential and occupied states of ions in the SF and the occurrence probability of the permeation mode of ions and resulting in the change in the permeability of the channel. Compared with no external electric field, when the external electric field with 15 THz frequency is applied, the lifetime of the hydrogen bond is reduced by 29%, the probability of the "soft knock on" mode is decreased by 46.9%, and the ion flux of the channel is activated by 67.7%. Our research results support the view that compared to "direct knock-on", "soft knock-on" is a slower permeation mode.
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Affiliation(s)
- Wen Ding
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xiaofei Zhao
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Hongguang Wang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yize Wang
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yanjiang Liu
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Lirong Gong
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Shu Lin
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Chunliang Liu
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yongdong Li
- Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
- School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China
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27
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Seiffert S, Pendziwiat M, Hedrich UBS, Helbig I, Weber Y, Schwarz N. KCNC2 variants of uncertain significance are also associated to various forms of epilepsy. Front Neurol 2023; 14:1212079. [PMID: 37360341 PMCID: PMC10289024 DOI: 10.3389/fneur.2023.1212079] [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: 04/25/2023] [Accepted: 05/25/2023] [Indexed: 06/28/2023] Open
Abstract
Recently, de novo variants in KCNC2, coding for the potassium channel subunit KV3.2, have been described as causative for various forms of epilepsy including genetic generalized epilepsy (GGE) and developmental and epileptic encephalopathy (DEE). Here, we report the functional characteristics of three additional KCNC2 variants of uncertain significance and one variant classified as pathogenic. Electrophysiological studies were performed in Xenopus laevis oocytes. The data presented here support that KCNC2 variants with uncertain significance may also be causative for various forms of epilepsy, as they show changes in the current amplitude and activation and deactivation kinetics of the channel, depending on the variant. In addition, we investigated the effect of valproic acid on KV3.2, as several patients carrying pathogenic variants in the KCNC2 gene achieved significant seizure reduction or seizure freedom with this drug. However, in our electrophysiological investigations, no change on the behavior of KV3.2 channels could be observed, suggesting that the therapeutic effect of VPA may be explained by other mechanisms.
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Affiliation(s)
- Simone Seiffert
- Department of Human Genetics, University Hospital Ulm, Ulm, Germany
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Manuela Pendziwiat
- Institute of Clinical Molecular Biology, Christian-Albrechts-University of Kiel, Kiel, Germany
- Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Christian-Albrechts-University, Kiel, Germany
| | - Ulrike B. S. Hedrich
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Ingo Helbig
- Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Christian-Albrechts-University, Kiel, Germany
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
- The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Department of Biomedical and Health Informatics (DBHi), Children’s Hospital of Philadelphia, Philadelphia, PA, United States
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Yvonne Weber
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Epileptology and Neurology, University of Aachen, Aachen, Germany
| | - Niklas Schwarz
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
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28
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Huang H, Shakkottai VG. Targeting Ion Channels and Purkinje Neuron Intrinsic Membrane Excitability as a Therapeutic Strategy for Cerebellar Ataxia. Life (Basel) 2023; 13:1350. [PMID: 37374132 DOI: 10.3390/life13061350] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/03/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
In degenerative neurological disorders such as Parkinson's disease, a convergence of widely varying insults results in a loss of dopaminergic neurons and, thus, the motor symptoms of the disease. Dopamine replacement therapy with agents such as levodopa is a mainstay of therapy. Cerebellar ataxias, a heterogeneous group of currently untreatable conditions, have not been identified to have a shared physiology that is a target of therapy. In this review, we propose that perturbations in cerebellar Purkinje neuron intrinsic membrane excitability, a result of ion channel dysregulation, is a common pathophysiologic mechanism that drives motor impairment and vulnerability to degeneration in cerebellar ataxias of widely differing genetic etiologies. We further propose that treatments aimed at restoring Purkinje neuron intrinsic membrane excitability have the potential to be a shared therapy in cerebellar ataxia akin to levodopa for Parkinson's disease.
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Affiliation(s)
- Haoran Huang
- Medical Scientist Training Program, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - Vikram G Shakkottai
- Department of Neurology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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29
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Koch NA, Sonnenberg L, Hedrich UBS, Lauxmann S, Benda J. Loss or gain of function? Effects of ion channel mutations on neuronal firing depend on the neuron type. Front Neurol 2023; 14:1194811. [PMID: 37292138 PMCID: PMC10244640 DOI: 10.3389/fneur.2023.1194811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/03/2023] [Indexed: 06/10/2023] Open
Abstract
Introduction Clinically relevant mutations to voltage-gated ion channels, called channelopathies, alter ion channel function, properties of ionic currents, and neuronal firing. The effects of ion channel mutations are routinely assessed and characterized as loss of function (LOF) or gain of function (GOF) at the level of ionic currents. However, emerging personalized medicine approaches based on LOF/GOF characterization have limited therapeutic success. Potential reasons are among others that the translation from this binary characterization to neuronal firing is currently not well-understood-especially when considering different neuronal cell types. In this study, we investigate the impact of neuronal cell type on the firing outcome of ion channel mutations. Methods To this end, we simulated a diverse collection of single-compartment, conductance-based neuron models that differed in their composition of ionic currents. We systematically analyzed the effects of changes in ion current properties on firing in different neuronal types. Additionally, we simulated the effects of known mutations in KCNA1 gene encoding the KV1.1 potassium channel subtype associated with episodic ataxia type 1 (EA1). Results These simulations revealed that the outcome of a given change in ion channel properties on neuronal excitability depends on neuron type, i.e., the properties and expression levels of the unaffected ionic currents. Discussion Consequently, neuron-type specific effects are vital to a full understanding of the effects of channelopathies on neuronal excitability and are an important step toward improving the efficacy and precision of personalized medicine approaches.
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Affiliation(s)
- Nils A. Koch
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, Tübingen, Germany
| | - Lukas Sonnenberg
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, Tübingen, Germany
| | - Ulrike B. S. Hedrich
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Stephan Lauxmann
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, University of Tübingen, Tübingen, Germany
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Jan Benda
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, Tübingen, Germany
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30
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Paulhus K, Glasscock E. Novel Genetic Variants Expand the Functional, Molecular, and Pathological Diversity of KCNA1 Channelopathy. Int J Mol Sci 2023; 24:8826. [PMID: 37240170 PMCID: PMC10219020 DOI: 10.3390/ijms24108826] [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: 04/26/2023] [Revised: 05/11/2023] [Accepted: 05/13/2023] [Indexed: 05/28/2023] Open
Abstract
The KCNA1 gene encodes Kv1.1 voltage-gated potassium channel α subunits, which are crucial for maintaining healthy neuronal firing and preventing hyperexcitability. Mutations in the KCNA1 gene can cause several neurological diseases and symptoms, such as episodic ataxia type 1 (EA1) and epilepsy, which may occur alone or in combination, making it challenging to establish simple genotype-phenotype correlations. Previous analyses of human KCNA1 variants have shown that epilepsy-linked mutations tend to cluster in regions critical for the channel's pore, whereas EA1-associated mutations are evenly distributed across the length of the protein. In this review, we examine 17 recently discovered pathogenic or likely pathogenic KCNA1 variants to gain new insights into the molecular genetic basis of KCNA1 channelopathy. We provide the first systematic breakdown of disease rates for KCNA1 variants in different protein domains, uncovering potential location biases that influence genotype-phenotype correlations. Our examination of the new mutations strengthens the proposed link between the pore region and epilepsy and reveals new connections between epilepsy-related variants, genetic modifiers, and respiratory dysfunction. Additionally, the new variants include the first two gain-of-function mutations ever discovered for KCNA1, the first frameshift mutation, and the first mutations located in the cytoplasmic N-terminal domain, broadening the functional and molecular scope of KCNA1 channelopathy. Moreover, the recently identified variants highlight emerging links between KCNA1 and musculoskeletal abnormalities and nystagmus, conditions not typically associated with KCNA1. These findings improve our understanding of KCNA1 channelopathy and promise to enhance personalized diagnosis and treatment for individuals with KCNA1-linked disorders.
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Affiliation(s)
| | - Edward Glasscock
- Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, USA;
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31
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Qin C, Yang X, Zhang Y, Deng G, Huang X, Zuo Z, Sun F, Cao Z, Chen Z, Wu Y. Functional Characterization of a New Degradation Peptide BmTX4-P1 from Traditional Chinese Scorpion Medicinal Material. Toxins (Basel) 2023; 15:toxins15050340. [PMID: 37235373 DOI: 10.3390/toxins15050340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/28/2023] [Accepted: 04/29/2023] [Indexed: 05/28/2023] Open
Abstract
Thermally processed Buthus martensii Karsch scorpion is an important traditional Chinese medical material that has been widely used to treat various diseases in China for over one thousand years. Our recent work showed that thermally processed Buthus martensii Karsch scorpions contain many degraded peptides; however, the pharmacological activities of these peptides remain to be studied. Here, a new degraded peptide, BmTX4-P1, was identified from processed Buthus martensii Karsch scorpions. Compared with the venom-derived wild-type toxin peptide BmTX4, BmTX4-P1 missed some amino acids at the N-terminal and C-terminal regions, while containing six conserved cysteine residues, which could be used to form disulfide bond-stabilized α-helical and β-sheet motifs. Two methods (chemical synthesis and recombinant expression) were used to obtain the BmTX4-P1 peptide, named sBmTX4-P1 and rBmTX4-P1. Electrophysiological experimental results showed that sBmTX4-P1 and rBmTX4-P1 exhibited similar activities to inhibit the currents of hKv1.2 and hKv1.3 channels. In addition, the experimental electrophysiological results of recombinant mutant peptides of BmTX4-P1 indicated that the two residues of BmTX4-P1 (Lys22 and Tyr31) were the key residues for its potassium channel inhibitory activity. In addition to identifying a new degraded peptide, BmTX4-P1, from traditional Chinese scorpion medicinal material with high inhibitory activities against the hKv1.2 and hKv1.3 channels, this study also provided a useful method to obtain the detailed degraded peptides from processed Buthus martensii Karsch scorpions. Thus, the study laid a solid foundation for further research on the medicinal function of these degraded peptides.
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Affiliation(s)
- Chenhu Qin
- College of Life Sciences, Wuhan University, Wuhan 430072, China
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan 442000, China
| | - Xuhua Yang
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Yuanyuan Zhang
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Gang Deng
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Xin Huang
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Zheng Zuo
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Fang Sun
- College of Life Sciences, Wuhan University, Wuhan 430072, China
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan 442000, China
| | - Zhijian Cao
- College of Life Sciences, Wuhan University, Wuhan 430072, China
- Center for BioDrug Research, Wuhan University, Wuhan 430072, China
| | - Zongyun Chen
- College of Life Sciences, Wuhan University, Wuhan 430072, China
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Hubei University of Medicine, Shiyan 442000, China
| | - Yingliang Wu
- College of Life Sciences, Wuhan University, Wuhan 430072, China
- Center for BioDrug Research, Wuhan University, Wuhan 430072, China
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Chen S, Neale BM, Berkovic SF. Shared and distinct ultra-rare genetic risk for diverse epilepsies: A whole-exome sequencing study of 54,423 individuals across multiple genetic ancestries. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.02.22.23286310. [PMID: 36865150 PMCID: PMC9980234 DOI: 10.1101/2023.02.22.23286310] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Identifying genetic risk factors for highly heterogeneous disorders like epilepsy remains challenging. Here, we present the largest whole-exome sequencing study of epilepsy to date to investigate rare variants that confer risk for a spectrum of epilepsy syndromes. With an unprecedented sample size of >54,000 human exomes, composed of 20,979 deep-phenotyped patients with epilepsy and 33,444 controls, we replicate previous gene findings at exome-wide significance; using a hypothesis-free approach, we identify potential novel associations. Most discoveries are specific to a particular subtype of epilepsy, highlighting distinct genetic contributions to different epilepsies. Combining evidence from rare single nucleotide/short indel-, copy number-, and common variants, we find convergence of different genetic risk factors at the level of individual genes. Further comparing to other exome-sequencing studies, we implicate shared rare variant risk between epilepsy and other neurodevelopmental disorders. Our study also demonstrates the value of collaborative sequencing and deep-phenotyping efforts, which will continue to unravel the complex genetic architecture underlying the heterogeneity of epilepsy.
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Affiliation(s)
- Siwei Chen
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Benjamin M Neale
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Samuel F Berkovic
- Epilepsy Research Centre, University of Melbourne, Austin Health, Heidelberg 3084, Australia
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Müller P, Takacs DS, Hedrich UBS, Coorg R, Masters L, Glinton KE, Dai H, Cokley JA, Riviello JJ, Lerche H, Cooper EC. KCNA1 gain-of-function epileptic encephalopathy treated with 4-aminopyridine. Ann Clin Transl Neurol 2023; 10:656-663. [PMID: 36793218 PMCID: PMC10109319 DOI: 10.1002/acn3.51742] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/31/2023] [Indexed: 02/17/2023] Open
Abstract
Precision medicine for Mendelian epilepsy is rapidly developing. We describe an early infant with severely pharmacoresistant multifocal epilepsy. Exome sequencing revealed the de novo variant p.(Leu296Phe) in the gene KCNA1, encoding the voltage-gated K+ channel subunit KV 1.1. So far, loss-of-function variants in KCNA1 have been associated with episodic ataxia type 1 or epilepsy. Functional studies of the mutated subunit in oocytes revealed a gain-of-function caused by a hyperpolarizing shift of voltage dependence. Leu296Phe channels are sensitive to block by 4-aminopyridine. Clinical use of 4-aminopyridine was associated with reduced seizure burden, enabled simplification of co-medication and prevented rehospitalization.
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Affiliation(s)
- Peter Müller
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, 72076, Germany
| | - Danielle S Takacs
- Division of Neurology and Developmental Neuroscience, Epilepsy and Neurophysiology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA.,Department of Neurology, Baylor College of Medicine, Houston, Texas, USA
| | - Ulrike B S Hedrich
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, 72076, Germany
| | - Rohini Coorg
- Division of Neurology and Developmental Neuroscience, Epilepsy and Neurophysiology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA.,Department of Neurology, Baylor College of Medicine, Houston, Texas, USA
| | - Laura Masters
- Division of Neurology and Developmental Neuroscience, Epilepsy and Neurophysiology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA.,Department of Neurology, Baylor College of Medicine, Houston, Texas, USA
| | - Kevin E Glinton
- Division of Genetics, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Hongzheng Dai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Baylor Genetics, Houston, Texas, USA
| | - Jon A Cokley
- Division of Neurology and Developmental Neuroscience, Epilepsy and Neurophysiology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - James J Riviello
- Division of Neurology and Developmental Neuroscience, Epilepsy and Neurophysiology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA.,Department of Neurology, Baylor College of Medicine, Houston, Texas, USA
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, 72076, Germany
| | - Edward C Cooper
- Department of Neurology, Baylor College of Medicine, Houston, Texas, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
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Salpietro V, Galassi Deforie V, Efthymiou S, O'Connor E, Marcé‐Grau A, Maroofian R, Striano P, Zara F, Morrow MM, Reich A, Blevins A, Sala‐Coromina J, Accogli A, Fortuna S, Alesandrini M, Au PYB, Singhal NS, Cogne B, Isidor B, Hanna MG, Macaya A, Kullmann DM, Houlden H, Männikkö R. De novo KCNA6 variants with attenuated K V 1.6 channel deactivation in patients with epilepsy. Epilepsia 2023; 64:443-455. [PMID: 36318112 PMCID: PMC10108282 DOI: 10.1111/epi.17455] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/31/2022] [Accepted: 10/31/2022] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Mutations in the genes encoding neuronal ion channels are a common cause of Mendelian neurological diseases. We sought to identify novel de novo sequence variants in cases with early infantile epileptic phenotypes and neurodevelopmental anomalies. METHODS Following clinical diagnosis, we performed whole exome sequencing of the index cases and their parents. Identified channel variants were expressed in Xenopus oocytes and their functional properties assessed using two-electrode voltage clamp. RESULTS We identified novel de novo variants in KCNA6 in four unrelated individuals variably affected with neurodevelopmental disorders and seizures with onset in the first year of life. Three of the four identified mutations affect the pore-lining S6 α-helix of KV 1.6. A prominent finding of functional characterization in Xenopus oocytes was that the channel variants showed only minor effects on channel activation but slowed channel closure and shifted the voltage dependence of deactivation in a hyperpolarizing direction. Channels with a mutation affecting the S6 helix display dominant effects on channel deactivation when co-expressed with wild-type KV 1.6 or KV 1.1 subunits. SIGNIFICANCE This is the first report of de novo nonsynonymous variants in KCNA6 associated with neurological or any clinical features. Channel variants showed a consistent effect on channel deactivation, slowing the rate of channel closure following normal activation. This specific gain-of-function feature is likely to underlie the neurological phenotype in our patients. Our data highlight KCNA6 as a novel channelopathy gene associated with early infantile epileptic phenotypes and neurodevelopmental anomalies.
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Affiliation(s)
- Vincenzo Salpietro
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
- Department of Biotechnological and Applied Clinical Sciences (DISCAB)University of L'AquilaL'AquilaItaly
| | | | - Stephanie Efthymiou
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
| | - Emer O'Connor
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
| | - Anna Marcé‐Grau
- Department of Paediatric Neurology, University Hospital Vall d'HebronUniversitat Autònoma de BarcelonaBarcelonaSpain
| | - Reza Maroofian
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI)University of Genoa16124 GenoaItaly
- Unit of Pediatric NeurologyIRCCS, Istituto “Giannina Gaslini”Genoa 16123Italy
| | - Federico Zara
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI)University of Genoa16124 GenoaItaly
- Medical Genetics UnitIRCCS, Istituto “Giannina Gaslini”Genoa 16123Italy
| | | | | | | | | | - Júlia Sala‐Coromina
- Department of Paediatric Neurology, University Hospital Vall d'HebronUniversitat Autònoma de BarcelonaBarcelonaSpain
| | - Andrea Accogli
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI)University of Genoa16124 GenoaItaly
- Medical Genetics UnitIRCCS, Istituto “Giannina Gaslini”Genoa 16123Italy
| | | | - Marie Alesandrini
- Neuropediatrics UnitCentre Hospitalier Universitaire NantesNantesFrance
| | - P. Y. Billie Au
- Department of Medical Genetics, Alberta Children's Hospital Research Institute, Cumming School of MedicineUniversity of CalgaryAlbertaCalgaryCanada
| | - Nilika Shah Singhal
- Departments of Neurology and Pediatrics, UCSF Benioff Children's HospitalUniversity of CaliforniaCaliforniaSan FranciscoUSA
| | - Benjamin Cogne
- Centre Hospitalier Universitaire NantesService de Génétique MédicaleNantesFrance
- Université de Nantes, CNRS, INSERML'Institut du ThoraxNantesFrance
| | - Bertrand Isidor
- Centre Hospitalier Universitaire NantesService de Génétique MédicaleNantesFrance
- Université de Nantes, CNRS, INSERML'Institut du ThoraxNantesFrance
| | - Michael G. Hanna
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
- Queen Square Centre for Neuromuscular DiseasesNational Hospital for Neurology and NeurosurgeryLondonUK
| | - Alfons Macaya
- Department of Paediatric Neurology, University Hospital Vall d'HebronUniversitat Autònoma de BarcelonaBarcelonaSpain
| | - Dimitri M. Kullmann
- Department of Clinical and Experimental EpilepsyUCL Institute of Neurology, University College LondonLondonUK
| | - Henry Houlden
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
| | - Roope Männikkö
- Department of Neuromuscular DiseaseUCL Institute of Neurology, University College LondonLondonUK
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35
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Nugent FS, Kirkwood A, Lupica CR, Sjöström PJ. Editorial: The synaptic basis of neuropathology. Front Synaptic Neurosci 2022; 14:1043480. [PMID: 36311440 PMCID: PMC9608123 DOI: 10.3389/fnsyn.2022.1043480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 09/29/2022] [Indexed: 01/27/2023] Open
Affiliation(s)
- Fereshteh S. Nugent
- F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, MD, United States
| | - Alfredo Kirkwood
- Department of Neuroscience, Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, United States
| | - Carl R. Lupica
- National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, United States,*Correspondence: Carl R. Lupica
| | - P. Jesper Sjöström
- Brain Repair and Integrative Neuroscience Program, Department of Medicine, Department of Neurology and Neurosurgery, Centre for Research in Neuroscience, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, QC, Canada,P. Jesper Sjöström
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36
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Gao K, Lin Z, Wen S, Jiang Y. Potassium channels and epilepsy. Acta Neurol Scand 2022; 146:699-707. [PMID: 36225112 DOI: 10.1111/ane.13695] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 08/16/2022] [Indexed: 01/10/2023]
Abstract
With the development and application of next-generation sequencing technology, the aetiological diagnosis of genetic epilepsy is rapidly becoming easier and less expensive. Additionally, there is a growing body of research into precision therapy based on genetic diagnosis. The numerous genes in the potassium ion channel family constitute the largest family of ion channels: this family is divided into different subtypes. Potassium ion channels play a crucial role in the electrical activity of neurons and are directly involved in the mechanism of epileptic seizures. In China, scientific research on genetic diagnosis and studies of precision therapy for genetic epilepsy are progressing rapidly. Many cases of epilepsy caused by mutation of potassium channel genes have been identified, and several potassium channel gene targets and drug candidates have been discovered. The purpose of this review is to briefly summarize the progress of research on the precise diagnosis and treatment of potassium ion channel-related genetic epilepsy, especially the research conducted in China. Here in, we review several large cohort studies on the genetic diagnosis of epilepsy in China in recent years, summarized the proportion of potassium channel genes. We focus on the progress of precison therapy on some hot epilepsy related potassium channel genes: KCNA1, KCNA2, KCNB1, KCNC1, KCND2, KCNQ2, KCNQ3, KCNMA1, and KCNT1.
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Affiliation(s)
- Kai Gao
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China.,Children Epilepsy Center, Peking University First Hospital, Beijing, China.,Key Laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Zehong Lin
- Department of Neurology, Affiliated Children's Hospital of Capital Institute of Pediatrics, Beijing, China
| | - Sijia Wen
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China.,Children Epilepsy Center, Peking University First Hospital, Beijing, China
| | - Yuwu Jiang
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China.,Children Epilepsy Center, Peking University First Hospital, Beijing, China.,Key Laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China.,Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing, China
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37
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Knowles JK, Helbig I, Metcalf CS, Lubbers LS, Isom LL, Demarest S, Goldberg EM, George AL, Lerche H, Weckhuysen S, Whittemore V, Berkovic SF, Lowenstein DH. Precision medicine for genetic epilepsy on the horizon: Recent advances, present challenges, and suggestions for continued progress. Epilepsia 2022; 63:2461-2475. [PMID: 35716052 PMCID: PMC9561034 DOI: 10.1111/epi.17332] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 06/14/2022] [Accepted: 06/14/2022] [Indexed: 01/18/2023]
Abstract
The genetic basis of many epilepsies is increasingly understood, giving rise to the possibility of precision treatments tailored to specific genetic etiologies. Despite this, current medical therapy for most epilepsies remains imprecise, aimed primarily at empirical seizure reduction rather than targeting specific disease processes. Intellectual and technological leaps in diagnosis over the past 10 years have not yet translated to routine changes in clinical practice. However, the epilepsy community is poised to make impressive gains in precision therapy, with continued innovation in gene discovery, diagnostic ability, and bioinformatics; increased access to genetic testing and counseling; fuller understanding of natural histories; agility and rigor in preclinical research, including strategic use of emerging model systems; and engagement of an evolving group of stakeholders (including patient advocates, governmental resources, and clinicians and scientists in academia and industry). In each of these areas, we highlight notable examples of recent progress, new or persistent challenges, and future directions. The future of precision medicine for genetic epilepsy looks bright if key opportunities on the horizon can be pursued with strategic and coordinated effort.
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Affiliation(s)
- Juliet K. Knowles
- Department of Neurology, Division of Child Neurology, Stanford University School of Medicine, Stanford, California, USA
| | - Ingo Helbig
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Biomedical and Health Informatics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Institute of Clinical Molecular Biology, University of Kiel, Kiel, Germany
- Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel, Germany
| | - Cameron S. Metcalf
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
| | - Laura S. Lubbers
- Citizens United for Research in Epilepsy, Chicago, Illinois, USA
| | - Lori L. Isom
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Scott Demarest
- Department of Pediatrics and Neurology, University of Colorado, School of Medicine, Aurora, Colorado, USA
| | - Ethan M. Goldberg
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Alfred L. George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Sarah Weckhuysen
- Division of Neurology, University Hospital Antwerp, Antwerp, Belgium
- Applied and Translational Neurogenomics Group, Vlaams Instituut voor Biotechnologie Center for Molecular Neurology, Antwerp, Belgium
- Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium
- μNEURO Research Center of Excellence, University of Antwerp, Antwerp, Belgium
| | - Vicky Whittemore
- Division of Neuroscience, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Rockville, Maryland, USA
| | - Samuel F. Berkovic
- Epilepsy Research Centre, Department of Medicine, Austin Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Daniel H. Lowenstein
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
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38
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van der Knoop MM, Maroofian R, Fukata Y, van Ierland Y, Karimiani EG, Lehesjoki AE, Muona M, Paetau A, Miyazaki Y, Hirano Y, Selim L, de França M, Fock RA, Beetz C, Ruivenkamp CAL, Eaton AJ, Morneau-Jacob FD, Sagi-Dain L, Shemer-Meiri L, Peleg A, Haddad-Halloun J, Kamphuis DJ, Peeters-Scholte CMPCD, Kurul SH, Horvath R, Lochmüller H, Murphy D, Waldmüller S, Spranger S, Overberg D, Muir AM, Rad A, Vona B, Abdulwahad F, Maddirevula S, Povolotskaya IS, Voinova VY, Gowda VK, Srinivasan VM, Alkuraya FS, Mefford HC, Alfadhel M, Haack TB, Striano P, Severino M, Fukata M, Hilhorst-Hofstee Y, Houlden H. Biallelic ADAM22 pathogenic variants cause progressive encephalopathy and infantile-onset refractory epilepsy. Brain 2022; 145:2301-2312. [PMID: 35373813 PMCID: PMC9337806 DOI: 10.1093/brain/awac116] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/31/2022] [Accepted: 03/04/2022] [Indexed: 12/03/2022] Open
Abstract
Pathogenic variants in A Disintegrin And Metalloproteinase (ADAM) 22, the postsynaptic cell membrane receptor for the glycoprotein leucine-rich repeat glioma-inactivated protein 1 (LGI1), have been recently associated with recessive developmental and epileptic encephalopathy. However, so far, only two affected individuals have been described and many features of this disorder are unknown. We refine the phenotype and report 19 additional individuals harbouring compound heterozygous or homozygous inactivating ADAM22 variants, of whom 18 had clinical data available. Additionally, we provide follow-up data from two previously reported cases. All affected individuals exhibited infantile-onset, treatment-resistant epilepsy. Additional clinical features included moderate to profound global developmental delay/intellectual disability (20/20), hypotonia (12/20) and delayed motor development (19/20). Brain MRI findings included cerebral atrophy (13/20), supported by post-mortem histological examination in patient-derived brain tissue, cerebellar vermis atrophy (5/20), and callosal hypoplasia (4/20). Functional studies in transfected cell lines confirmed the deleteriousness of all identified variants and indicated at least three distinct pathological mechanisms: (i) defective cell membrane expression; (ii) impaired LGI1-binding; and/or (iii) impaired interaction with the postsynaptic density protein PSD-95. We reveal novel clinical and molecular hallmarks of ADAM22 deficiency and provide knowledge that might inform clinical management and early diagnostics.
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Affiliation(s)
- Marieke M van der Knoop
- Department of Child Neurology, Sophia Children’s Hospital, Erasmus University Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Reza Maroofian
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Yuko Fukata
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8585, Japan
| | - Yvette van Ierland
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Ehsan G Karimiani
- Next Generation Genetic Polyclinic, Razavi International Hospital, Mashhad, Iran
- Genetics Research Centre, Molecular and Clinical Sciences Institute, St. George’s University, London SW17 0RE, UK
| | - Anna Elina Lehesjoki
- Folkhälsan Research Center, Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki 00290, Finland
| | - Mikko Muona
- Folkhälsan Research Center, Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki 00290, Finland
- Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Finland,00100 Helsinki, Finland
- Blueprint Genetics, 02150 Espoo, Finland
| | - Anders Paetau
- Department of Pathology, Medicum, University of Helsinki, 00100 Helsinki, Finland
| | - Yuri Miyazaki
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8585, Japan
| | - Yoko Hirano
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Bunkyo, Tokyo 113-8655, Japan
| | - Laila Selim
- Division of Neurology and Metabolism, Kasr Al Ainy School of Medicine, Cairo University Children Hospital, Cairo, Egypt
| | - Marina de França
- Department of Morphology and Genetics, Clinical Center of Medical Genetics Federal, University of São Paulo, São Paulo, Brazil
| | - Rodrigo Ambrosio Fock
- Department of Morphology and Genetics, Clinical Center of Medical Genetics Federal, University of São Paulo, São Paulo, Brazil
| | | | - Claudia A L Ruivenkamp
- Department of Clinical Genetics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | - Alison J Eaton
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | | | - Lena Sagi-Dain
- Affiliated to the Ruth and Bruce Rappaport Faculty of Medicine Technion-Israel Institute of Technology, Genetics Institute, Carmel Medical Center,Haifa, Israel
| | | | - Amir Peleg
- Affiliated to the Ruth and Bruce Rappaport Faculty of Medicine Technion-Israel Institute of Technology, Genetics Institute, Carmel Medical Center,Haifa, Israel
| | - Jumana Haddad-Halloun
- Department of Biology, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Daan J Kamphuis
- Department of Neurology, Reinier de Graaf Hospital, 2625 AD Delft, The Netherlands
| | | | - Semra Hiz Kurul
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
- Izmir International Biomedicine and Genome Institute, Dokuz Eylul University, Izmir, Turkey
- Department of Paediatric Neurology, School of Medicine, Dokuz Eylul University, Izmir, Turkey
| | - Rita Horvath
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Hanns Lochmüller
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada
- Department of Neuropediatrics and Muscle Disorders, Medical Center–University of Freiburg, Faculty of Medicine, Freiburg, Germany
- Division of Neurology, Department of Medicine, The Ottawa Hospital; and Brain and Mind Research Institute, University of Ottawa, Ottawa, Canada
| | - David Murphy
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Stephan Waldmüller
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen 72076, Germany
| | | | - David Overberg
- Department of Pediatrics, Klinikum Bremen-Mitte, Bremen 28205, Germany
| | - Alison M Muir
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Seattle Children’s Hospital, Seattle, WA 98195, USA
| | - Aboulfazl Rad
- Department of Otolaryngology - Head and Neck Surgery, Tübingen Hearing Research Centre, Eberhard Karls University Tübingen, Tübingen 72076, Germany
| | - Barbara Vona
- Department of Otolaryngology - Head and Neck Surgery, Tübingen Hearing Research Centre, Eberhard Karls University Tübingen, Tübingen 72076, Germany
| | - Firdous Abdulwahad
- Department of Translational Genomics, King Faisal Specialist Hospital and Research Center, Riyadh 11564, Saudi Arabia
| | - Sateesh Maddirevula
- Department of Translational Genomics, King Faisal Specialist Hospital and Research Center, Riyadh 11564, Saudi Arabia
| | - Inna S Povolotskaya
- Veltischev Research and Clinical Institute for Pediatrics of the Pirogov Russian National Research Medical University of the Russian Ministry of Health, Moscow, Russia
| | - Victoria Y Voinova
- Veltischev Research and Clinical Institute for Pediatrics of the Pirogov Russian National Research Medical University of the Russian Ministry of Health, Moscow, Russia
- Mental Health Research Center, Moscow 107076, Russia
| | - Vykuntaraju K Gowda
- Department of Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, India
| | | | - Fowzan S Alkuraya
- Department of Translational Genomics, King Faisal Specialist Hospital and Research Center, Riyadh 11564, Saudi Arabia
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Seattle Children’s Hospital, Seattle, WA 98195, USA
| | - Majid Alfadhel
- Genetics and Precision Medicine Department, King Abdullah Specialized Children's Hospital (KASCH), King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (MNG-HA), Riyadh, Saudi Arabia
- Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud Bin Abdulaziz University for Health Sciences, King AbdulAziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen 72076, Germany
- Centre for Rare Diseases, University of Tübingen, Tübingen 72076, Germany
| | - Pasquale Striano
- IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
| | | | - Masaki Fukata
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8585, Japan
| | - Yvonne Hilhorst-Hofstee
- Department of Clinical Genetics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | - Henry Houlden
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
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39
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Soldovieri MV, Taglialatela M. The long and winding road to personalized medicine in KCNMA1-linked channelopathies revealed by novel variants associated with the Liang-Wang syndrome. Acta Physiol (Oxf) 2022; 235:e13854. [PMID: 35730691 DOI: 10.1111/apha.13854] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 06/17/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Maria Virginia Soldovieri
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy
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40
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Bavan S, Goodkin HP, Papazian DM. Altered Closed State Inactivation Gating in Kv4.2 Channels Results in Developmental and Epileptic Encephalopathies in Human Patients. Hum Mutat 2022; 43:1286-1298. [PMID: 35510384 DOI: 10.1002/humu.24396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 04/27/2022] [Accepted: 05/01/2022] [Indexed: 11/06/2022]
Abstract
Kv4.2 subunits, encoded by KCND2, serve as the pore-forming components of voltage-gated, inactivating ISA K+ channels expressed in the brain. ISA channels inactivate without opening in response to subthreshold excitatory input, temporarily increasing neuronal excitability, the back propagation of action potentials, and Ca2+ influx into dendrites, thereby regulating mechanisms of spike timing-dependent synaptic plasticity. As previously described, a de novo variant in Kv4.2, p.Val404Met, is associated with an infant-onset developmental and epileptic encephalopathy (DEE) in monozygotic twin boys. The p.Val404Met variant enhances inactivation directly from closed states, but dramatically impairs inactivation after channel opening. We now report the identification of a closely related, novel, de novo variant in Kv4.2, p.Val402Leu, in a boy with an early-onset pharmacoresistant epilepsy that evolved to an epileptic aphasia syndrome (Continuous Spike Wave during Sleep Syndrome). Like p.Val404Met, the p.Val402Leu variant increases the rate of inactivation from closed states, but significantly slows inactivation after the pore opens. Although quantitatively the p.Val402Leu mutation alters channel kinetics less dramatically than p.Val404Met, our results strongly support the conclusion that p.Val402Leu and p.Val404Met cause the clinical features seen in the affected individuals and underscore the importance of closed state inactivation in ISA channels in normal brain development and function. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Selvan Bavan
- Department of Physiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095-1571.,Labcorp Drug Development, Huntingdon, PE28 4HS, UK
| | - Howard P Goodkin
- Departments of Neurology and Pediatrics, University of Virginia School of Medicine, Charlottesville, VA, 22903
| | - Diane M Papazian
- Department of Physiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095-1571
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41
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Lange LM, Gonzalez-Latapi P, Rajalingam R, Tijssen MAJ, Ebrahimi-Fakhari D, Gabbert C, Ganos C, Ghosh R, Kumar KR, Lang AE, Rossi M, van der Veen S, van de Warrenburg B, Warner T, Lohmann K, Klein C, Marras C. Nomenclature of Genetic Movement Disorders: Recommendations of the International Parkinson and Movement Disorder Society Task Force - An Update. Mov Disord 2022; 37:905-935. [PMID: 35481685 DOI: 10.1002/mds.28982] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/28/2022] [Accepted: 02/14/2022] [Indexed: 12/13/2022] Open
Abstract
In 2016, the Movement Disorder Society Task Force for the Nomenclature of Genetic Movement Disorders presented a new system for naming genetically determined movement disorders and provided a criterion-based list of confirmed monogenic movement disorders. Since then, a substantial number of novel disease-causing genes have been described, which warrant classification using this system. In addition, with this update, we further refined the system and propose dissolving the imaging-based categories of Primary Familial Brain Calcification and Neurodegeneration with Brain Iron Accumulation and reclassifying these genetic conditions according to their predominant phenotype. We also introduce the novel category of Mixed Movement Disorders (MxMD), which includes conditions linked to multiple equally prominent movement disorder phenotypes. In this article, we present updated lists of newly confirmed monogenic causes of movement disorders. We found a total of 89 different newly identified genes that warrant a prefix based on our criteria; 6 genes for parkinsonism, 21 for dystonia, 38 for dominant and recessive ataxia, 5 for chorea, 7 for myoclonus, 13 for spastic paraplegia, 3 for paroxysmal movement disorders, and 6 for mixed movement disorder phenotypes; 10 genes were linked to combined phenotypes and have been assigned two new prefixes. The updated lists represent a resource for clinicians and researchers alike and they have also been published on the website of the Task Force for the Nomenclature of Genetic Movement Disorders on the homepage of the International Parkinson and Movement Disorder Society (https://www.movementdisorders.org/MDS/About/Committees--Other-Groups/MDS-Task-Forces/Task-Force-on-Nomenclature-in-Movement-Disorders.htm). © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.
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Affiliation(s)
- Lara M Lange
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Paulina Gonzalez-Latapi
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada.,Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Rajasumi Rajalingam
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Marina A J Tijssen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Carolin Gabbert
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christos Ganos
- Department of Neurology, Charité University Hospital Berlin, Berlin, Germany
| | - Rhia Ghosh
- Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Kishore R Kumar
- Molecular Medicine Laboratory and Department of Neurology, Concord Repatriation General Hospital, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Anthony E Lang
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Malco Rossi
- Movement Disorders Section, Neuroscience Department, Raul Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina
| | - Sterre van der Veen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bart van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Center of Expertise for Parkinson and Movement Disorders, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom Warner
- Department of Clinical & Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Katja Lohmann
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Connie Marras
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
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42
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Nilsson M, Lindström SH, Kaneko M, Wang K, Minguez-Viñas T, Angelini M, Steccanella F, Holder D, Ottolia M, Olcese R, Pantazis A. An epilepsy-associated K V1.2 charge-transfer-center mutation impairs K V1.2 and K V1.4 trafficking. Proc Natl Acad Sci U S A 2022; 119:e2113675119. [PMID: 35439054 PMCID: PMC9169947 DOI: 10.1073/pnas.2113675119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 02/25/2022] [Indexed: 12/19/2022] Open
Abstract
We report on a heterozygous KCNA2 variant in a child with epilepsy. KCNA2 encodes KV1.2 subunits, which form homotetrameric potassium channels and participate in heterotetrameric channel complexes with other KV1-family subunits, regulating neuronal excitability. The mutation causes substitution F233S at the KV1.2 charge transfer center of the voltage-sensing domain. Immunocytochemical trafficking assays showed that KV1.2(F233S) subunits are trafficking deficient and reduce the surface expression of wild-type KV1.2 and KV1.4: a dominant-negative phenotype extending beyond KCNA2, likely profoundly perturbing electrical signaling. Yet some KV1.2(F233S) trafficking was rescued by wild-type KV1.2 and KV1.4 subunits, likely in permissible heterotetrameric stoichiometries: electrophysiological studies utilizing applied transcriptomics and concatemer constructs support that up to one or two KV1.2(F233S) subunits can participate in trafficking-capable heterotetramers with wild-type KV1.2 or KV1.4, respectively, and that both early and late events along the biosynthesis and secretion pathway impair trafficking. These studies suggested that F233S causes a depolarizing shift of ∼48 mV on KV1.2 voltage dependence. Optical tracking of the KV1.2(F233S) voltage-sensing domain (rescued by wild-type KV1.2 or KV1.4) revealed that it operates with modestly perturbed voltage dependence and retains pore coupling, evidenced by off-charge immobilization. The equivalent mutation in the Shaker K+ channel (F290S) was reported to modestly affect trafficking and strongly affect function: an ∼80-mV depolarizing shift, disrupted voltage sensor activation and pore coupling. Our work exposes the multigenic, molecular etiology of a variant associated with epilepsy and reveals that charge-transfer-center disruption has different effects in KV1.2 and Shaker, the archetypes for potassium channel structure and function.
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Affiliation(s)
- Michelle Nilsson
- Division of Neurobiology, Department of Biomedical and Clinical Sciences (BKV), Linköping University, 581 83 Linköping, Sweden
| | - Sarah H. Lindström
- Division of Neurobiology, Department of Biomedical and Clinical Sciences (BKV), Linköping University, 581 83 Linköping, Sweden
| | - Maki Kaneko
- Center for Personalized Medicine, Children's Hospital Los Angeles, Los Angeles, CA 90027
- Division of Genomic Medicine, Department of Pathology, Children's Hospital Los Angeles, Los Angeles, CA 90027
| | - Kaiqian Wang
- Division of Neurobiology, Department of Biomedical and Clinical Sciences (BKV), Linköping University, 581 83 Linköping, Sweden
| | - Teresa Minguez-Viñas
- Division of Neurobiology, Department of Biomedical and Clinical Sciences (BKV), Linköping University, 581 83 Linköping, Sweden
| | - Marina Angelini
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Federica Steccanella
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Deborah Holder
- Comprehensive Epilepsy Program, Children's Hospital Los Angeles, Los Angeles, CA 90027
| | - Michela Ottolia
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- UCLA Cardiovascular Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Riccardo Olcese
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- UCLA Cardiovascular Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- Brain Research Institute, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Antonios Pantazis
- Division of Neurobiology, Department of Biomedical and Clinical Sciences (BKV), Linköping University, 581 83 Linköping, Sweden
- Wallenberg Center for Molecular Medicine, Linköping University, 581 83 Linköping, Sweden
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43
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Absalom NL, Liao VWY, Johannesen KMH, Gardella E, Jacobs J, Lesca G, Gokce-Samar Z, Arzimanoglou A, Zeidler S, Striano P, Meyer P, Benkel-Herrenbrueck I, Mero IL, Rummel J, Chebib M, Møller RS, Ahring PK. Gain-of-function and loss-of-function GABRB3 variants lead to distinct clinical phenotypes in patients with developmental and epileptic encephalopathies. Nat Commun 2022; 13:1822. [PMID: 35383156 PMCID: PMC8983652 DOI: 10.1038/s41467-022-29280-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 03/08/2022] [Indexed: 12/23/2022] Open
Abstract
Many patients with developmental and epileptic encephalopathies present with variants in genes coding for GABAA receptors. These variants are presumed to cause loss-of-function receptors leading to reduced neuronal GABAergic activity. Yet, patients with GABAA receptor variants have diverse clinical phenotypes and many are refractory to treatment despite the availability of drugs that enhance GABAergic activity. Here we show that 44 pathogenic GABRB3 missense variants segregate into gain-of-function and loss-of-function groups and respective patients display distinct clinical phenotypes. The gain-of-function cohort (n = 27 patients) presented with a younger age of seizure onset, higher risk of severe intellectual disability, focal seizures at onset, hypotonia, and lower likelihood of seizure freedom in response to treatment. Febrile seizures at onset are exclusive to the loss-of-function cohort (n = 47 patients). Overall, patients with GABRB3 variants that increase GABAergic activity have more severe developmental and epileptic encephalopathies. This paradoxical finding challenges our current understanding of the GABAergic system in epilepsy and how patients should be treated.
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Affiliation(s)
- Nathan L Absalom
- Brain and Mind Centre, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,School of Science, Western Sydney University, Sydney, NSW, Australia
| | - Vivian W Y Liao
- Brain and Mind Centre, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Katrine M H Johannesen
- Department of Epilepsy Genetics and Personalized Treatment, Member of the ERN EpiCARE, The Danish Epilepsy Centre, Dianalund, Denmark.,Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Elena Gardella
- Department of Epilepsy Genetics and Personalized Treatment, Member of the ERN EpiCARE, The Danish Epilepsy Centre, Dianalund, Denmark.,Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Julia Jacobs
- Department of Neuropediatrics and Muscle Disorders, Medical Center-University of Freiburg, Freiburg, Germany.,Department of Paediatrics and Department of Neuroscience, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Gaetan Lesca
- Department of Medical Genetics, Member of the ERN EpiCARE, University Hospitals of Lyon (HCL), Lyon, France.,Institut Neuromyogène, CNRS UMR 5310 - INSERM U1217, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Zeynep Gokce-Samar
- Department of Paediatric Clinical Epileptology, Sleep Disorders and Functional Neurology, Member of the ERN EpiCARE, University Hospitals of Lyon (HCL), Lyon, France
| | - Alexis Arzimanoglou
- Department of Paediatric Clinical Epileptology, Sleep Disorders and Functional Neurology, Member of the ERN EpiCARE, University Hospitals of Lyon (HCL), Lyon, France
| | - Shimriet Zeidler
- Department of Clinical Genetics, Erasmus MC, Rotterdam, The Netherlands
| | - Pasquale Striano
- IRCCS Institute "Giannina Gaslini", Genova, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
| | - Pierre Meyer
- Pediatric Neurology Department, Phymedexp, Montpellier University, Inserm, CRNS, Montpellier University Hospital, Montpellier, France
| | - Ira Benkel-Herrenbrueck
- Sana-Krankenhaus Düsseldorf-Gerresheim, Academic Teaching Hospital der Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Inger-Lise Mero
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Jutta Rummel
- Department of Neurohabilitation, Oslo University Hospital, Oslo, Norway
| | - Mary Chebib
- Brain and Mind Centre, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Rikke S Møller
- Department of Epilepsy Genetics and Personalized Treatment, Member of the ERN EpiCARE, The Danish Epilepsy Centre, Dianalund, Denmark. .,Department of Regional Health Research, University of Southern Denmark, Odense, Denmark.
| | - Philip K Ahring
- Brain and Mind Centre, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.
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44
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Wang H, Zhu Y, Cao D, Chen H, Ding X, Zeng Q, Zou H, Liao J. Successful medical treatment of west syndrome with a KCNA2 variant: a case report. ACTA EPILEPTOLOGICA 2022. [DOI: 10.1186/s42494-021-00069-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
West syndrome is a devastating disorder characterized by a triad of epileptic spasms, abnormal electroencephalography (EEG), and developmental arrest or psychomotor delay. In addition to early diagnosis, knowing the etiology of the condition is also important for its treatment. Among various etiologies, the genetic factors, especially mutations of ion channel genes, are very common and strongly linked to West syndrome.
Case presentation
A boy who had epileptic spasms from the age of 4 months was diagnosed with West syndrome based on the clinical manifestation and EEG results in Shenzhen Children’s Hospital in June 2019. Trios whole-exome sequencing (WES) test and protein structural model prediction were performed. We also reviewed the clinical and genetic features of this syndrome and the mechanisms of action of topiramate (TPM) by literature search in databases of Online Mendelian Inheritance in Man, Clinical Genome Resource, PubMed, Chinese National Knowledge Infrastructure and Wanfang database using keywords “KCNA2” “West syndrome” and “Topiramate” by December 2020. The relationship between the effect of TPM and the pathogenesis of the KCNA2 variant was also assessed. The WES test revealed c.244C > T/p. Arg82Cys varaint of KCNA2 (NM_004974.3) in this patient, and Sanger sequencing identified this was a de novo mutation. As far as we know, this is the first report of the c.244C > T/p. Arg82Cys variant in KCNA2, which was likely a pathogenic mutation. The seizures were successfully controlled for 10 months by TPM after failure of sodium valproate, large doses of vitamin B6, and adrenocorticotropic hormone. We speculate that the therapeutic effect of TPM in this patient is partially due to the inhibition of carbonic anhydrase.
Conclusions
Mutations in the KCNA2 gene should be considered for patients with West syndrome. The TPM treatment is probably effective for KCNA2-associated disorders.
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45
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Perilli L, Mastromoro G, Murciano M, Amedeo I, Avenoso F, Pizzuti A, Guido CA, Spalice A. Myoclonic Epilepsy: Case Report of a Mild Phenotype in a Pediatric Patient Expanding Clinical Spectrum of KCNA2 Pathogenic Variants. Front Neurol 2022; 12:806516. [PMID: 35178022 PMCID: PMC8844549 DOI: 10.3389/fneur.2021.806516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/31/2021] [Indexed: 11/24/2022] Open
Abstract
We report on the rare case of a male toddler presenting with myoclonic epilepsy characterized by daily episodes of upward movements of the eyebrows, and myoclonic jerks of both head and upper limbs. In addition, the child showed speech delay, tremors, and lack of motor coordination. Next Generation Sequencing analysis (NGS) performed in trio revealed in the proband the c.889C>T de novo missense variant in the KCNA2 gene in heterozygous state. This is the first case of myoclonic epilepsy in a toddler due to a c.889C>T KCNA2 missense variant. The patient was treated with valproic acid and ethosuximide with a good clinical response. At 6 years old, follow-up revealed that the proband was seizure-free with tremors and clumsiness in movements. According to the literature, this case supports the correlation between myoclonic epilepsy and KCNA2 alterations. This evidence suggests that performing genomic testing including the KCNA2 gene in preschool patients affected by myoclonic epilepsy, especially when associated with delayed neurodevelopment. Our goal is to expand the phenotypical spectrum of this rare condition and adding clinical features following a genotype-first approach.
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Affiliation(s)
- Lorenzo Perilli
- Department of Mother and Child and Urological Sciences, Sapienza University of Rome, Rome, Italy
| | - Gioia Mastromoro
- Faculty of Medicine and Dentistry, Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Manuel Murciano
- Department of Mother and Child and Urological Sciences, Sapienza University of Rome, Rome, Italy.,Department of Emergency Pediatrics, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Ilaria Amedeo
- Department of Mother and Child and Urological Sciences, Sapienza University of Rome, Rome, Italy
| | - Federica Avenoso
- Department of Mother and Child and Urological Sciences, Sapienza University of Rome, Rome, Italy
| | - Antonio Pizzuti
- Faculty of Medicine and Dentistry, Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Cristiana Alessia Guido
- Department of Mother and Child and Urological Sciences, Sapienza University of Rome, Rome, Italy
| | - Alberto Spalice
- Department of Mother and Child and Urological Sciences, Sapienza University of Rome, Rome, Italy
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46
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Genetic paroxysmal neurological disorders featuring episodic ataxia and epilepsy. Eur J Med Genet 2022; 65:104450. [DOI: 10.1016/j.ejmg.2022.104450] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/02/2022] [Accepted: 02/06/2022] [Indexed: 01/25/2023]
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47
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Saini L, Singanamalla B, Natarajan R, Madaan P. Role of genotype–phenotype correlation in prognostication of a child with a novel potassium channelopathy. J Pediatr Neurosci 2022. [DOI: 10.4103/jpn.jpn_294_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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48
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Kingdom R, Wright CF. Incomplete Penetrance and Variable Expressivity: From Clinical Studies to Population Cohorts. Front Genet 2022; 13:920390. [PMID: 35983412 PMCID: PMC9380816 DOI: 10.3389/fgene.2022.920390] [Citation(s) in RCA: 63] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 06/09/2022] [Indexed: 12/20/2022] Open
Abstract
The same genetic variant found in different individuals can cause a range of diverse phenotypes, from no discernible clinical phenotype to severe disease, even among related individuals. Such variants can be said to display incomplete penetrance, a binary phenomenon where the genotype either causes the expected clinical phenotype or it does not, or they can be said to display variable expressivity, in which the same genotype can cause a wide range of clinical symptoms across a spectrum. Both incomplete penetrance and variable expressivity are thought to be caused by a range of factors, including common variants, variants in regulatory regions, epigenetics, environmental factors, and lifestyle. Many thousands of genetic variants have been identified as the cause of monogenic disorders, mostly determined through small clinical studies, and thus, the penetrance and expressivity of these variants may be overestimated when compared to their effect on the general population. With the wealth of population cohort data currently available, the penetrance and expressivity of such genetic variants can be investigated across a much wider contingent, potentially helping to reclassify variants that were previously thought to be completely penetrant. Research into the penetrance and expressivity of such genetic variants is important for clinical classification, both for determining causative mechanisms of disease in the affected population and for providing accurate risk information through genetic counseling. A genotype-based definition of the causes of rare diseases incorporating information from population cohorts and clinical studies is critical for our understanding of incomplete penetrance and variable expressivity. This review examines our current knowledge of the penetrance and expressivity of genetic variants in rare disease and across populations, as well as looking into the potential causes of the variation seen, including genetic modifiers, mosaicism, and polygenic factors, among others. We also considered the challenges that come with investigating penetrance and expressivity.
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Affiliation(s)
- Rebecca Kingdom
- Institute of Biomedical and Clinical Science, Royal Devon & Exeter Hospital, University of Exeter Medical School, Exeter, United Kingdom
| | - Caroline F Wright
- Institute of Biomedical and Clinical Science, Royal Devon & Exeter Hospital, University of Exeter Medical School, Exeter, United Kingdom
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49
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Costa F, Guardiani C, Giacomello A. Exploring K v 1.2 Channel Inactivation Through MD Simulations and Network Analysis. Front Mol Biosci 2021; 8:784276. [PMID: 34988118 PMCID: PMC8721119 DOI: 10.3389/fmolb.2021.784276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 11/12/2021] [Indexed: 12/12/2022] Open
Abstract
The KCNA2 gene encodes the K v 1.2 channel, a mammalian Shaker-like voltage-gated K+ channel, whose defections are linked to neuronal deficiency and childhood epilepsy. Despite the important role in the kinetic behavior of the channel, the inactivation remained hereby elusive. Here, we studied the K v 1.2 inactivation via a combined simulation/network theoretical approach that revealed two distinct pathways coupling the Voltage Sensor Domain and the Pore Domain to the Selectivity Filter. Additionally, we mutated some residues implicated in these paths and we explained microscopically their function in the inactivation mechanism by computing a contact map. Interestingly, some pathological residues shown to impair the inactivation lay on the paths. In summary, the presented results suggest two pathways as the possible molecular basis of the inactivation mechanism in the K v 1.2 channel. These pathways are consistent with earlier mutational studies and known mutations involved in neuronal channelopathies.
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Affiliation(s)
| | | | - Alberto Giacomello
- Dipartimento di Ingegneria Meccanica e Aerospaziale, Sapienza Università di Roma, Rome, Italy
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50
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Miceli F, Guerrini R, Nappi M, Soldovieri MV, Cellini E, Gurnett CA, Parmeggiani L, Mei D, Taglialatela M. Distinct epilepsy phenotypes and response to drugs in KCNA1 gain- and loss-of function variants. Epilepsia 2021; 63:e7-e14. [PMID: 34778950 PMCID: PMC9299230 DOI: 10.1111/epi.17118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/01/2021] [Accepted: 10/22/2021] [Indexed: 11/29/2022]
Abstract
A wide phenotypic spectrum of neurological diseases is associated with KCNA1 (Kv1.1) variants. To investigate the molecular basis of such a heterogeneous clinical presentation and identify the possible correlation with in vitro phenotypes, we compared the functional consequences of three heterozygous de novo variants (p.P403S, p.P405L, and p.P405S) in Kv1.1 pore region found in four patients with severe developmental and epileptic encephalopathy (DEE), with those of a de novo variant in the voltage sensor (p.A261T) identified in two patients with mild, carbamazepine-responsive, focal epilepsy. Patch-clamp electrophysiology was used to investigate the functional properties of mutant Kv1.1 subunits, both expressed as homomers and heteromers with wild-type Kv1.1 subunits. KCNA1 pore mutations markedly decreased (p. P405S) or fully suppressed (p. P403S, p. P405L) Kv1.1-mediated currents, exerting loss-of-function (LoF) effects. By contrast, channels carrying the p.A261T variant exhibited a hyperpolarizing shift of the activation process, consistent with a gain-of-function (GoF) effect. The present results unveil a novel correlation between in vitro phenotype (GoF vs LoF) and clinical course (mild vs severe) in KCNA1-related phenotypes. The excellent clinical response to carbamazepine observed in the patients carrying the A261T variant suggests an exquisite sensitivity of KCNA1 GoF to sodium channel inhibition that should be further explored.
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Affiliation(s)
- Francesco Miceli
- Department of Neuroscience, University of Naples "Federico II", Naples, Italy
| | - Renzo Guerrini
- Neuroscience Department, A. Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Mario Nappi
- Department of Neuroscience, University of Naples "Federico II", Naples, Italy
| | | | - Elena Cellini
- Neuroscience Department, A. Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Christina A Gurnett
- Department of Neurology, Washington University in St. Louis, St. Louis, Missouri, USA
| | | | - Davide Mei
- Neuroscience Department, A. Meyer Children's Hospital, University of Florence, Florence, Italy
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