1
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Johnson JP, Focken T, Karimi Tari P, Dube C, Goodchild SJ, Andrez JC, Bankar G, Burford K, Chang E, Chowdhury S, Christabel J, Dean R, de Boer G, Dehnhardt C, Gong W, Grimwood M, Hussainkhel A, Jia Q, Khakh K, Lee S, Li J, Lin S, Lindgren A, Lofstrand V, Mezeyova J, Nelkenbrecher K, Shuart NG, Sojo L, Sun S, Waldbrook M, Wesolowski S, Wilson M, Xie Z, Zenova A, Zhang W, Scott FL, Cutts AJ, Sherrington RP, Winquist R, Cohen CJ, Empfield JR. The contribution of Na V1.6 to the efficacy of voltage-gated sodium channel inhibitors in wild type and Na V1.6 gain-of-function (GOF) mouse seizure control. Br J Pharmacol 2024. [PMID: 38922847 DOI: 10.1111/bph.16481] [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: 12/21/2023] [Revised: 04/19/2024] [Accepted: 05/15/2024] [Indexed: 06/28/2024] Open
Abstract
BACKGROUND AND PURPOSE Inhibitors of voltage-gated sodium channels (NaVs) are important anti-epileptic drugs, but the contribution of specific channel isoforms is unknown since available inhibitors are non-selective. We aimed to create novel, isoform selective inhibitors of Nav channels as a means of informing the development of improved antiseizure drugs. EXPERIMENTAL APPROACH We created a series of compounds with diverse selectivity profiles enabling block of NaV1.6 alone or together with NaV1.2. These novel NaV inhibitors were evaluated for their ability to inhibit electrically evoked seizures in mice with a heterozygous gain-of-function mutation (N1768D/+) in Scn8a (encoding NaV1.6) and in wild-type mice. KEY RESULTS Pharmacologic inhibition of NaV1.6 in Scn8aN1768D/+ mice prevented seizures evoked by a 6-Hz shock. Inhibitors were also effective in a direct current maximal electroshock seizure assay in wild-type mice. NaV1.6 inhibition correlated with efficacy in both models, even without inhibition of other CNS NaV isoforms. CONCLUSIONS AND IMPLICATIONS Our data suggest NaV1.6 inhibition is a driver of efficacy for NaV inhibitor anti-seizure medicines. Sparing the NaV1.1 channels of inhibitory interneurons did not compromise efficacy. Selective NaV1.6 inhibitors may provide targeted therapies for human Scn8a developmental and epileptic encephalopathies and improved treatments for idiopathic epilepsies.
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Affiliation(s)
- James P Johnson
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Thilo Focken
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Parisa Karimi Tari
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Celine Dube
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Samuel J Goodchild
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | | | - Girish Bankar
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Kristen Burford
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Elaine Chang
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Sultan Chowdhury
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Jessica Christabel
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Richard Dean
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Gina de Boer
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Christoph Dehnhardt
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Wei Gong
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Michael Grimwood
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Angela Hussainkhel
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Qi Jia
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Kuldip Khakh
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Stephanie Lee
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Jenny Li
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Sophia Lin
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Andrea Lindgren
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Verner Lofstrand
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Janette Mezeyova
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Karen Nelkenbrecher
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Noah Gregory Shuart
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Luis Sojo
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Shaoyi Sun
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Matthew Waldbrook
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Steven Wesolowski
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Michael Wilson
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Zhiwei Xie
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Alla Zenova
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Wei Zhang
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | | | - Alison J Cutts
- Scientific Affairs, Xenon Pharmaceuticals, Inc, Burnaby, British Columbia, Canada
| | - Robin P Sherrington
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Raymond Winquist
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Charles J Cohen
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - James R Empfield
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
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2
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Li M, Kuhn B. Protocol for inducing severe Scn2a insufficiency in mice by intracerebroventricular antisense oligonucleotide injection. STAR Protoc 2024; 5:103094. [PMID: 38796847 PMCID: PMC11152730 DOI: 10.1016/j.xpro.2024.103094] [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: 01/31/2024] [Revised: 03/03/2024] [Accepted: 05/08/2024] [Indexed: 05/29/2024] Open
Abstract
SCN2A loss-of-function variants cause a range of neurodevelopmental disorders. Here, we present a protocol to induce severe Scn2a insufficiency in mice. We describe steps for intracerebroventricular (ICV) antisense oligonucleotide (ASO) injection that causes a selective downregulation of Scn2a and ASO-mediated mRNA degradation. We then detail procedures for qPCR and western blot protocol to measure Scn2a mRNA and protein. This protocol can be used as a mouse model for behavioral and in vivo two-photon Ca2+ imaging.
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Affiliation(s)
- Melody Li
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan.
| | - Bernd Kuhn
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan.
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3
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Dhureja M, Chaturvedi P, Choudhary A, Kumar P, Munshi A. Molecular Insights of Drug Resistance in Epilepsy: Multi-omics Unveil. Mol Neurobiol 2024:10.1007/s12035-024-04220-6. [PMID: 38753128 DOI: 10.1007/s12035-024-04220-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 05/03/2024] [Indexed: 06/12/2024]
Abstract
Epilepsy is a devastating neurological disorder mainly associated with impaired synchronic discharge that leads to sensory, motor, and psychomotor impairments. Till now, about 30 anti-seizure medications (ASMs) have been approved for the management of epilepsy, yet one-third of individuals still have uncontrollable epilepsy and develop resistance. Drug resistance epilepsy (DRE) is defined as the condition where two ASMs fail to control the seizure in epileptic patients. The leading cause of the resistance was the extended use of ASMs. According to various studies, alterations in some genes and their expressions, along with specific metabolic impairments, are suggested to be associated with ASMs resistance and DRE pathophysiology. Several factors aid in the pathophysiology of DRE, such as alterations in protein-encoding genes such as neurotransmitter receptors, drug transporters, ion channels, and drug targets. Furthermore, the altered metabolite levels of metabolites implicated in neurotransmitter signaling, energetic pathways, oxidative stress, and neuroinflammatory signaling differentiate the epileptic patient from the DRE patient. Various DRE biomarkers can be identified using the "integrated omics approach," which includes the study of genomics, transcriptomics, and metabolomics. The current review has been compiled to understand the pathophysiological mechanisms of DRE by focusing on genomics, transcriptomics, and metabolomics. An effort has also been made to identify the therapeutic targets based on identifying significant markers by a multi-omics approach. This has the potential to develop novel therapeutic interventions in the future.
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Affiliation(s)
- Maanvi Dhureja
- Department of Pharmacology, Central University of Punjab, Bathinda, India
| | - Pragya Chaturvedi
- Department of Human Genetics and Molecular Medicines, Central University of Punjab, Bathinda, India
| | - Anita Choudhary
- Department of Human Genetics and Molecular Medicines, Central University of Punjab, Bathinda, India
| | - Puneet Kumar
- Department of Pharmacology, Central University of Punjab, Bathinda, India.
| | - Anjana Munshi
- Department of Human Genetics and Molecular Medicines, Central University of Punjab, Bathinda, India.
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4
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Mao M, Mattei C, Rollo B, Byars S, Cuddy C, Berecki G, Heighway J, Pachernegg S, Menheniott T, Apted D, Jia L, Dalby K, Nemiroff A, Mullen S, Reid CA, Maljevic S, Petrou S. Distinctive In Vitro Phenotypes in iPSC-Derived Neurons From Patients With Gain- and Loss-of-Function SCN2A Developmental and Epileptic Encephalopathy. J Neurosci 2024; 44:e0692232023. [PMID: 38148154 PMCID: PMC10883610 DOI: 10.1523/jneurosci.0692-23.2023] [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: 04/17/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 12/28/2023] Open
Abstract
SCN2A encodes NaV1.2, an excitatory neuron voltage-gated sodium channel and a major monogenic cause of neurodevelopmental disorders, including developmental and epileptic encephalopathies (DEE) and autism. Clinical presentation and pharmocosensitivity vary with the nature of SCN2A variant dysfunction and can be divided into gain-of-function (GoF) cases with pre- or peri-natal seizures and loss-of-function (LoF) patients typically having infantile spasms after 6 months of age. We established and assessed patient induced pluripotent stem cell (iPSC) - derived neuronal models for two recurrent SCN2A DEE variants with GoF R1882Q and LoF R853Q associated with early- and late-onset DEE, respectively. Two male patient-derived iPSC isogenic pairs were differentiated using Neurogenin-2 overexpression yielding populations of cortical-like glutamatergic neurons. Functional properties were assessed using patch clamp and multielectrode array recordings and transcriptomic profiles obtained with total mRNA sequencing after 2-4 weeks in culture. At 3 weeks of differentiation, increased neuronal activity at cellular and network levels was observed for R1882Q iPSC-derived neurons. In contrast, R853Q neurons showed only subtle changes in excitability after 4 weeks and an overall reduced network activity after 7 weeks in vitro. Consistent with the reported efficacy in some GoF SCN2A patients, phenytoin (sodium channel blocker) reduced the excitability of neurons to the control levels in R1882Q neuronal cultures. Transcriptomic alterations in neurons were detected for each variant and convergent pathways suggested potential shared mechanisms underlying SCN2A DEE. In summary, patient iPSC-derived neuronal models of SCN2A GoF and LoF pathogenic variants causing DEE show specific functional and transcriptomic in vitro phenotypes.
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Affiliation(s)
- Miaomiao Mao
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Cristiana Mattei
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Ben Rollo
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria 3800, Australia
| | - Sean Byars
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Claire Cuddy
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Geza Berecki
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Jacqueline Heighway
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Svenja Pachernegg
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Victoria 3052, Australia
| | - Trevelyan Menheniott
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Victoria 3052, Australia
| | - Danielle Apted
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Linghan Jia
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Kelley Dalby
- Rogcon Biosciences, Cambridge, MA 02142
- Praxis Precision Medicines, Inc., Cambridge, MA 02142
| | - Alex Nemiroff
- Rogcon Biosciences, Cambridge, MA 02142
- Praxis Precision Medicines, Inc., Cambridge, MA 02142
| | - Saul Mullen
- Austin Health, University of Melbourne, Melbourne, Victoria 3084, Australia
| | - Christopher A Reid
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Snezana Maljevic
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Steven Petrou
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
- Praxis Precision Medicines, Inc., Cambridge, MA 02142
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5
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Gu J, Rollo B, Berecki G, Petrou S, Kwan P, Sumer H, Cromer B. Generation of a stably transfected mouse embryonic stem cell line for inducible differentiation to excitatory neurons. Exp Cell Res 2024; 435:113902. [PMID: 38145818 DOI: 10.1016/j.yexcr.2023.113902] [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: 11/09/2023] [Revised: 12/14/2023] [Accepted: 12/21/2023] [Indexed: 12/27/2023]
Abstract
In vitro differentiation of stem cells into various cell lineages is valuable in developmental studies and an important source of cells for modelling physiology and pathology, particularly for complex tissues such as the brain. Conventional protocols for in vitro neuronal differentiation often suffer from complicated procedures, high variability and low reproducibility. Over the last decade, the identification of cell fate-determining transcription factors has provided new tools for cellular studies in neuroscience and enabled rapid differentiation driven by ectopic transcription factor expression. As a proneural transcription factor, Neurogenin 2 (Ngn2) expression alone is sufficient to trigger rapid and robust neurogenesis from pluripotent cells. Here, we established a stable cell line, by piggyBac (PB) transposition, that conditionally expresses Ngn2 for generation of excitatory neurons from mouse embryonic stem cells (ESCs) using an all-in-one PB construct. Our results indicate that Ngn2-induced excitatory neurons have mature and functional characteristics consistent with previous studies using conventional differentiation methods. This approach provides an all-in-one PB construct for rapid and high copy number gene delivery of dox-inducible transcription factors to induce differentiation. This approach is a valuable in vitro cell model for disease modeling, drug screening and cell therapy.
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Affiliation(s)
- Jinchao Gu
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Australia; Department of Neuroscience, Central Clinical School, Monash University, Alfred Centre, Melbourne, Australia
| | - Ben Rollo
- Department of Neuroscience, Central Clinical School, Monash University, Alfred Centre, Melbourne, Australia
| | - Geza Berecki
- Ion Channels and Human Diseases Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Steven Petrou
- Ion Channels and Human Diseases Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Patrick Kwan
- Department of Neuroscience, Central Clinical School, Monash University, Alfred Centre, Melbourne, Australia
| | - Huseyin Sumer
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Australia.
| | - Brett Cromer
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Australia.
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6
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Hadjipanteli A, Theodosiou A, Papaevripidou I, Evangelidou P, Alexandrou A, Salameh N, Kallikas I, Kakoullis K, Frakala S, Oxinou C, Marnerides A, Kousoulidou L, Anastasiadou VC, Sismani C. Sodium Channel Gene Variants in Fetuses with Abnormal Sonographic Findings: Expanding the Prenatal Phenotypic Spectrum of Sodium Channelopathies. Genes (Basel) 2024; 15:119. [PMID: 38255008 PMCID: PMC10815715 DOI: 10.3390/genes15010119] [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: 12/21/2023] [Revised: 01/08/2024] [Accepted: 01/17/2024] [Indexed: 01/24/2024] Open
Abstract
Voltage-gated sodium channels (VGSCs) are responsible for the initiation and propagation of action potentials in the brain and muscle. Pathogenic variants in genes encoding VGSCs have been associated with severe disorders including epileptic encephalopathies and congenital myopathies. In this study, we identified pathogenic variants in genes encoding the α subunit of VGSCs in the fetuses of two unrelated families with the use of trio-based whole exome sequencing, as part of a larger cohort study. Sanger sequencing was performed for variant confirmation as well as parental phasing. The fetus of the first family carried a known de novo heterozygous missense variant in the SCN2A gene (NM_001040143.2:c.751G>A p.(Val251Ile)) and presented intrauterine growth retardation, hand clenching and ventriculomegaly. Neonatally, the proband also exhibited refractory epilepsy, spasms and MRI abnormalities. The fetus of the second family was a compound heterozygote for two parentally inherited novel missense variants in the SCN4A gene (NM_000334.4:c.4340T>C, p.(Phe1447Ser), NM_000334.4:c.3798G>C, p.(Glu1266Asp)) and presented a severe prenatal phenotype including talipes, fetal hypokinesia, hypoplastic lungs, polyhydramnios, ear abnormalities and others. Both probands died soon after birth. In a subsequent pregnancy of the latter family, the fetus was also a compound heterozygote for the same parentally inherited variants. This pregnancy was terminated due to multiple ultrasound abnormalities similar to the first pregnancy. Our results suggest a potentially crucial role of the VGSC gene family in fetal development and early lethality.
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Affiliation(s)
- Andrea Hadjipanteli
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | - Athina Theodosiou
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | - Ioannis Papaevripidou
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | - Paola Evangelidou
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | - Angelos Alexandrou
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | - Nicole Salameh
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | | | | | | | - Christina Oxinou
- Christina Oxinou Histopathology/Cytology Laboratory, 1065 Nicosia, Cyprus
| | | | - Ludmila Kousoulidou
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
| | | | - Carolina Sismani
- The Cyprus Institute of Neurology and Genetics, Cytogenetics and Genomics, 2371 Nicosia, Cyprus; (A.H.)
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7
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Lauffer MC, van Roon-Mom W, Aartsma-Rus A. Possibilities and limitations of antisense oligonucleotide therapies for the treatment of monogenic disorders. COMMUNICATIONS MEDICINE 2024; 4:6. [PMID: 38182878 PMCID: PMC10770028 DOI: 10.1038/s43856-023-00419-1] [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: 05/10/2023] [Accepted: 11/27/2023] [Indexed: 01/07/2024] Open
Abstract
Antisense oligonucleotides (ASOs) are incredibly versatile molecules that can be designed to specifically target and modify RNA transcripts to slow down or halt rare genetic disease progression. They offer the potential to target groups of patients or can be tailored for individual cases. Nonetheless, not all genetic variants and disorders are amenable to ASO-based treatments, and hence, it is important to consider several factors before embarking on the drug development journey. Here, we discuss which genetic disorders have the potential to benefit from a specific type of ASO approach, based on the pathophysiology of the disease and pathogenic variant type, as well as those disorders that might not be suitable for ASO therapies. We further explore additional aspects, such as the target tissues, intervention time points, and potential clinical benefits, which need to be considered before developing a compound. Overall, we provide an overview of the current potentials and limitations of ASO-based therapeutics for the treatment of monogenic disorders.
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Affiliation(s)
- Marlen C Lauffer
- Dutch Center for RNA Therapeutics, Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Willeke van Roon-Mom
- Dutch Center for RNA Therapeutics, Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Annemieke Aartsma-Rus
- Dutch Center for RNA Therapeutics, Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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8
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Hansen SN, Holm A, Kauppinen S, Klitgaard H. RNA therapeutics for epilepsy: An emerging modality for drug discovery. Epilepsia 2023; 64:3113-3129. [PMID: 37703096 DOI: 10.1111/epi.17772] [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: 06/14/2023] [Revised: 09/04/2023] [Accepted: 09/11/2023] [Indexed: 09/14/2023]
Abstract
Drug discovery in epilepsy began with the finding of potassium bromide by Sir Charles Locock in 1857. The following century witnessed the introduction of phenotypic screening tests for discovering antiseizure medications (ASMs). Despite the high success rate of developing ASMs, they have so far failed in eliminating drug resistance and in delivering disease-modifying treatments. This emphasizes the need for new drug discovery strategies in epilepsy. RNA-based drugs have recently shown promise as a new modality with the potential of providing disease modification and counteracting drug resistance in epilepsy. RNA therapeutics can be directed either toward noncoding RNAs, such as microRNAs, long noncoding RNAs (ncRNAs), and circular RNAs, or toward messenger RNAs. The former show promise in sporadic, nongenetic epilepsies, as interference with ncRNAs allows for modulation of entire disease pathways, whereas the latter seem more promising in monogenic childhood epilepsies. Here, we describe therapeutic strategies for modulating disease-associated RNA molecules and highlight the potential of RNA therapeutics for the treatment of different patient populations such as sporadic, drug-resistant epilepsy, and childhood monogenic epilepsies.
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Affiliation(s)
| | - Anja Holm
- Department of Clinical Medicine, Center for RNA Medicine, Aalborg University, Copenhagen, Denmark
| | - Sakari Kauppinen
- Department of Clinical Medicine, Center for RNA Medicine, Aalborg University, Copenhagen, Denmark
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9
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Canalis E, Mocarska M, Schilling L, Jafar-Nejad P, Carrer M. Antisense oligonucleotides targeting a NOTCH3 mutation in male mice ameliorate the cortical osteopenia of lateral meningocele syndrome. Bone 2023; 177:116898. [PMID: 37704069 PMCID: PMC10591917 DOI: 10.1016/j.bone.2023.116898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/15/2023]
Abstract
Lateral Meningocele Syndrome (LMS) is a monogenic disorder associated with NOTCH3 pathogenic variants that result in the stabilization of NOTCH3 and a gain-of-function. A mouse model (Notch3em1Ecan) harboring a 6691-TAATGA mutation in the Notch3 locus that results in a functional outcome analogous to LMS exhibits cancellous and cortical bone osteopenia. We tested Notch3 antisense oligonucleotides (ASOs) specific to the Notch36691-TAATGA mutation for their effects on Notch3 downregulation and on the osteopenia of Notch3em1Ecan mice. Twenty-four mouse Notch3 mutant ASOs were designed and tested for toxic effects in vivo, and 12 safe ASOs were tested for their impact on the downregulation of Notch36691-TAATGA and Notch3 mRNA in osteoblast cultures from Notch3em1Ecan mice. Three ASOs downregulated Notch3 mutant transcripts specifically and were tested in vivo for their effects on the bone microarchitecture of Notch3em1Ecan mice. All three ASOs were well tolerated. One of these ASOs had more consistent effects in vivo and was studied in detail. The Notch3 mutant ASO downregulated Notch3 mutant transcripts in osteoblasts and bone marrow stromal cells and had no effect on other Notch receptors. The subcutaneous administration of Notch3 mutant ASO at 50 mg/Kg decreased Notch36691-TAATGA mRNA in bone without apparent toxicity; microcomputed tomography demonstrated that the ASO ameliorated the cortical osteopenia of Notch3em1Ecan mice but not the cancellous bone osteopenia. In conclusion, a Notch3 ASO that downregulates Notch3 mutant expression specifically ameliorates the cortical osteopenia in Notch3em1Ecan mice. ASOs may become useful strategies in the management of monogenic disorders affecting the skeleton.
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Affiliation(s)
- Ernesto Canalis
- Department of Orthopaedic Surgery, UConn Health, Farmington, CT, USA; Department of Medicine, UConn Health, Farmington, CT, USA; UConn Musculoskeletal Institute, UConn Health, Farmington, CT, USA.
| | - Magda Mocarska
- UConn Musculoskeletal Institute, UConn Health, Farmington, CT, USA
| | - Lauren Schilling
- UConn Musculoskeletal Institute, UConn Health, Farmington, CT, USA
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10
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Li M, Eltabbal M, Tran HD, Kuhn B. Scn2a insufficiency alters spontaneous neuronal Ca 2+ activity in somatosensory cortex during wakefulness. iScience 2023; 26:108138. [PMID: 37876801 PMCID: PMC10590963 DOI: 10.1016/j.isci.2023.108138] [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: 04/17/2023] [Revised: 07/22/2023] [Accepted: 10/02/2023] [Indexed: 10/26/2023] Open
Abstract
SCN2A protein-truncating variants (PTV) can result in neurological disorders such as autism spectrum disorder and intellectual disability, but they are less likely to cause epilepsy in comparison to missense variants. While in vitro studies showed PTV reduce action potential firing, consequences at in vivo network level remain elusive. Here, we generated a mouse model of Scn2a insufficiency using antisense oligonucleotides (Scn2a ASO mice), which recapitulated key clinical feature of SCN2A PTV disorders. Simultaneous two-photon Ca2+ imaging and electrocorticography (ECoG) in awake mice showed that spontaneous Ca2+ transients in somatosensory cortical neurons, as well as their pairwise co-activities were generally decreased in Scn2a ASO mice during spontaneous awake state and induced seizure state. The reduction of neuronal activities and paired co-activity are mechanisms associated with motor, social and cognitive deficits observed in our mouse model of severe Scn2a insufficiency, indicating these are likely mechanisms driving SCN2A PTV pathology.
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Affiliation(s)
- Melody Li
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Mohamed Eltabbal
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Hoang-Dai Tran
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Bernd Kuhn
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
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11
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Borggraefe I, Wagner M. Precision Therapy in KCNQ2-Related Epilepsy. Neuropediatrics 2023; 54:295-296. [PMID: 37722392 DOI: 10.1055/s-0043-1772667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Affiliation(s)
- Ingo Borggraefe
- Department of Pediatrics, Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, Ludwig Maximilian University Munich, Munich, Germany
- Comprehensive Epilepsy Center for Children and Adolescents, University Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Matias Wagner
- Department of Pediatrics, Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, Ludwig Maximilian University Munich, Munich, Germany
- Institute of Neurogenomics, Helmholtz Centrum, Munich, Germany
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12
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Roshandel D, Sanders EJ, Shakeshaft A, Panjwani N, Lin F, Collingwood A, Hall A, Keenan K, Deneubourg C, Mirabella F, Topp S, Zarubova J, Thomas RH, Talvik I, Syvertsen M, Striano P, Smith AB, Selmer KK, Rubboli G, Orsini A, Ng CC, Møller RS, Lim KS, Hamandi K, Greenberg DA, Gesche J, Gardella E, Fong CY, Beier CP, Andrade DM, Jungbluth H, Richardson MP, Pastore A, Fanto M, Pal DK, Strug LJ. SLCO5A1 and synaptic assembly genes contribute to impulsivity in juvenile myoclonic epilepsy. NPJ Genom Med 2023; 8:28. [PMID: 37770509 PMCID: PMC10539321 DOI: 10.1038/s41525-023-00370-z] [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: 03/27/2023] [Accepted: 08/29/2023] [Indexed: 09/30/2023] Open
Abstract
Elevated impulsivity is a key component of attention-deficit hyperactivity disorder (ADHD), bipolar disorder and juvenile myoclonic epilepsy (JME). We performed a genome-wide association, colocalization, polygenic risk score, and pathway analysis of impulsivity in JME (n = 381). Results were followed up with functional characterisation using a drosophila model. We identified genome-wide associated SNPs at 8q13.3 (P = 7.5 × 10-9) and 10p11.21 (P = 3.6 × 10-8). The 8q13.3 locus colocalizes with SLCO5A1 expression quantitative trait loci in cerebral cortex (P = 9.5 × 10-3). SLCO5A1 codes for an organic anion transporter and upregulates synapse assembly/organisation genes. Pathway analysis demonstrates 12.7-fold enrichment for presynaptic membrane assembly genes (P = 0.0005) and 14.3-fold enrichment for presynaptic organisation genes (P = 0.0005) including NLGN1 and PTPRD. RNAi knockdown of Oatp30B, the Drosophila polypeptide with the highest homology to SLCO5A1, causes over-reactive startling behaviour (P = 8.7 × 10-3) and increased seizure-like events (P = 6.8 × 10-7). Polygenic risk score for ADHD genetically correlates with impulsivity scores in JME (P = 1.60 × 10-3). SLCO5A1 loss-of-function represents an impulsivity and seizure mechanism. Synaptic assembly genes may inform the aetiology of impulsivity in health and disease.
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Affiliation(s)
- Delnaz Roshandel
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Eric J Sanders
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
- Division of Biostatistics, Dalla Lana School of Public Health, The University of Toronto, Toronto, Canada
| | - Amy Shakeshaft
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | - Naim Panjwani
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Fan Lin
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Amber Collingwood
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Anna Hall
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Katherine Keenan
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Celine Deneubourg
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Filippo Mirabella
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Simon Topp
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Jana Zarubova
- Department of Neurology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czech Republic
| | - Rhys H Thomas
- Newcastle upon Tyne NHS Foundation Trust, Newcastle, UK
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | | | - Marte Syvertsen
- Department of Neurology, Drammen Hospital, Vestre Viken Health Trust, Oslo, Norway
| | - Pasquale Striano
- IRCCS Istituto 'G. Gaslini', Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
| | - Anna B Smith
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Kaja K Selmer
- Department of Research and Innovation, Division of Clinical Neuroscience, Oslo University Hospital, Oslo, Norway
- National Centre for Epilepsy, Oslo University Hospital, Oslo, Norway
| | - Guido Rubboli
- Danish Epilepsy Centre, Dianalund, Denmark
- University of Copenhagen, Copenhagen, Denmark
| | - Alessandro Orsini
- Pediatric Neurology, Azienda Ospedaliero-Universitaria Pisana, Pisa University Hospital, Pisa, Italy
| | - Ching Ching Ng
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Rikke S Møller
- Danish Epilepsy Centre, Dianalund, Denmark
- Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Kheng Seang Lim
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khalid Hamandi
- The Welsh Epilepsy Unit, Department of Neurology Cardiff & Vale University Health Board, Cardiff, UK
- Department of Psychological Medicine and Clinical Neuroscience, Cardiff University, Cardiff, UK
| | | | | | - Elena Gardella
- Danish Epilepsy Centre, Dianalund, Denmark
- Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Choong Yi Fong
- Division of Paediatric Neurology, Department of Pediatrics, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Danielle M Andrade
- Adult Epilepsy Genetics Program, Krembil Research Institute, University of Toronto, Toronto, Canada
| | - Heinz Jungbluth
- Randall Centre for Cell and Molecular Biophysics, Muscle Signalling Section, Faculty of Life Sciences and Medicine, King's College London, London, UK
- Department of Paediatric Neurology, Neuromuscular Service, Evelina's Children Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, London, UK
| | - Mark P Richardson
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
- King's College Hospital, London, UK
| | - Annalisa Pastore
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Manolis Fanto
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Deb K Pal
- Department of Basic & Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK.
- King's College Hospital, London, UK.
| | - Lisa J Strug
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada.
- Division of Biostatistics, Dalla Lana School of Public Health, The University of Toronto, Toronto, Canada.
- Departments of Statistical Sciences and Computer Science, The University of Toronto, Toronto, Canada.
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Canada.
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13
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Ovchinnikov DA, Jong S, Cuddy C, Scheffer IE, Maljevic S, Petrou S. Generation of an iPSC line (FINi001-A) from a girl with developmental and epileptic encephalopathy due to a heterozygous gain-of-function p.R1882Q variant in the voltage-gated sodium channel Na v1.2 protein encoded by the SCN2A gene. Stem Cell Res 2023; 71:103179. [PMID: 37597357 DOI: 10.1016/j.scr.2023.103179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/02/2023] [Accepted: 08/06/2023] [Indexed: 08/21/2023] Open
Abstract
A range of epilepsies, including the most severe group of developmental and epileptic encephalopathies (DEEs), are caused by gain-of-function variants in voltage-gated channels. Here we report the generation and characterisation of an iPSC cell line from the fibroblasts of a girl with early infantile DEE carrying heterozygous missense gain-of-function mutation (R1882Q) in Nav1.2(SCN2A) protein, using transient transfection with a single mRNA molecule. The established iPSC line displays typical human primed pluripotent stem cell characteristics: typical colony morphology and robust expression of pluripotency-associated marker genes, ability to give rise to derivatives of all three embryonic germ layers, and normal karyotype without any SNP array-detectable copy number variations. We anticipate that this iPSC line will be useful for the development of neuronal hyperactivity-caused human stem cell-based DEE models, advancing both understanding and potential therapy development for this debilitating condition.
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Affiliation(s)
- D A Ovchinnikov
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne 3010 VIC Australia
| | - S Jong
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne 3010 VIC Australia
| | - C Cuddy
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne 3010 VIC Australia
| | - I E Scheffer
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne 3010 VIC Australia; Departments of Medicine and Paediatrics, The University of Melbourne, Austin Health and Royal Children's Hospital, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - S Maljevic
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne 3010 VIC Australia
| | - S Petrou
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne 3010 VIC Australia; Praxis Precision Medicines, Cambridge, MA, USA.
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14
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Rusina E, Simonti M, Duprat F, Cestèle S, Mantegazza M. Voltage-gated sodium channels in genetic epilepsy: up and down of excitability. J Neurochem 2023. [PMID: 37654020 DOI: 10.1111/jnc.15947] [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: 07/16/2023] [Revised: 08/11/2023] [Accepted: 08/13/2023] [Indexed: 09/02/2023]
Abstract
The past two decades have witnessed a wide range of studies investigating genetic variants of voltage-gated sodium (NaV ) channels, which are involved in a broad spectrum of diseases, including several types of epilepsy. We have reviewed here phenotypes and pathological mechanisms of genetic epilepsies caused by variants in NaV α and β subunits, as well as of some relevant interacting proteins (FGF12/FHF1, PRRT2, and Ankyrin-G). Notably, variants of all these genes can induce either gain- or loss-of-function of NaV leading to either neuronal hyperexcitability or hypoexcitability. We present the results of functional studies obtained with different experimental models, highlighting that they should be interpreted considering the features of the experimental system used. These systems are models, but they have allowed us to better understand pathophysiological issues, ameliorate diagnostics, orientate genetic counseling, and select/develop therapies within a precision medicine framework. These studies have also allowed us to gain insights into the physiological roles of different NaV channels and of the cells that express them. Overall, our review shows the progress that has been made, but also the need for further studies on aspects that have not yet been clarified. Finally, we conclude by highlighting some significant themes of general interest that can be gleaned from the results of the work of the last two decades.
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Affiliation(s)
- Evgeniia Rusina
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
| | - Martina Simonti
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
| | - Fabrice Duprat
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
- Inserm, Valbonne-Sophia Antipolis, France
| | - Sandrine Cestèle
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
| | - Massimo Mantegazza
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
- Inserm, Valbonne-Sophia Antipolis, France
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15
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Abstract
In recent years, there has been a significant increase in preclinical studies to test genetic therapies for epilepsy. Some of these therapies have advanced to clinical trials and are being tested in patients with monogenetic or focal refractory epilepsy. This article provides an overview of the current state of preclinical studies that show potential for clinical translation. Specifically, we focus on genetic therapies that have demonstrated a clear effect on seizures in animal models and have the potential to be translated to clinical settings. Both therapies targeting the cause of the disease and those that treat symptoms are discussed. We believe that the next few years will be crucial in determining the potential of genetic therapies for treating patients with epilepsy.
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Affiliation(s)
- James S. Street
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Yichen Qiu
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Gabriele Lignani
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
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16
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Asadollahi R, Delvendahl I, Muff R, Tan G, Rodríguez DG, Turan S, Russo M, Oneda B, Joset P, Boonsawat P, Masood R, Mocera M, Ivanovski I, Baumer A, Bachmann-Gagescu R, Schlapbach R, Rehrauer H, Steindl K, Begemann A, Reis A, Winkler J, Winner B, Müller M, Rauch A. Pathogenic SCN2A variants cause early-stage dysfunction in patient-derived neurons. Hum Mol Genet 2023; 32:2192-2204. [PMID: 37010102 PMCID: PMC10281746 DOI: 10.1093/hmg/ddad048] [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: 11/14/2022] [Revised: 02/23/2023] [Accepted: 03/19/2023] [Indexed: 04/04/2023] Open
Abstract
Pathogenic heterozygous variants in SCN2A, which encodes the neuronal sodium channel NaV1.2, cause different types of epilepsy or intellectual disability (ID)/autism without seizures. Previous studies using mouse models or heterologous systems suggest that NaV1.2 channel gain-of-function typically causes epilepsy, whereas loss-of-function leads to ID/autism. How altered channel biophysics translate into patient neurons remains unknown. Here, we investigated iPSC-derived early-stage cortical neurons from ID patients harboring diverse pathogenic SCN2A variants [p.(Leu611Valfs*35); p.(Arg937Cys); p.(Trp1716*)] and compared them with neurons from an epileptic encephalopathy (EE) patient [p.(Glu1803Gly)] and controls. ID neurons consistently expressed lower NaV1.2 protein levels. In neurons with the frameshift variant, NaV1.2 mRNA and protein levels were reduced by ~ 50%, suggesting nonsense-mediated decay and haploinsufficiency. In other ID neurons, only protein levels were reduced implying NaV1.2 instability. Electrophysiological analysis revealed decreased sodium current density and impaired action potential (AP) firing in ID neurons, consistent with reduced NaV1.2 levels. In contrast, epilepsy neurons displayed no change in NaV1.2 levels or sodium current density, but impaired sodium channel inactivation. Single-cell transcriptomics identified dysregulation of distinct molecular pathways including inhibition of oxidative phosphorylation in neurons with SCN2A haploinsufficiency and activation of calcium signaling and neurotransmission in epilepsy neurons. Together, our patient iPSC-derived neurons reveal characteristic sodium channel dysfunction consistent with biophysical changes previously observed in heterologous systems. Additionally, our model links the channel dysfunction in ID to reduced NaV1.2 levels and uncovers impaired AP firing in early-stage neurons. The altered molecular pathways may reflect a homeostatic response to NaV1.2 dysfunction and can guide further investigations.
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Affiliation(s)
- R Asadollahi
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
- Faculty of Engineering and Science, University of Greenwich London, Medway Campus, Chatham Maritime ME4 4TB, UK
| | - I Delvendahl
- Department of Molecular Life Sciences, University of Zurich, Zurich 8057, Switzerland
- Neuroscience Center Zurich, University of Zurich, Zurich 8057, Switzerland
| | - R Muff
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - G Tan
- Functional Genomics Center Zurich, ETH Zurich and University of Zurich, Zurich 8057, Switzerland
| | - D G Rodríguez
- Functional Genomics Center Zurich, ETH Zurich and University of Zurich, Zurich 8057, Switzerland
| | - S Turan
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - M Russo
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - B Oneda
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - P Joset
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - P Boonsawat
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - R Masood
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - M Mocera
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - I Ivanovski
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - A Baumer
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - R Bachmann-Gagescu
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - R Schlapbach
- Functional Genomics Center Zurich, ETH Zurich and University of Zurich, Zurich 8057, Switzerland
| | - H Rehrauer
- Functional Genomics Center Zurich, ETH Zurich and University of Zurich, Zurich 8057, Switzerland
| | - K Steindl
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - A Begemann
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
| | - A Reis
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - J Winkler
- Department of Molecular Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
- Center for Rare Diseases Erlangen, University Hospital Erlangen, Erlangen 91054, Germany
| | - B Winner
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
- Center for Rare Diseases Erlangen, University Hospital Erlangen, Erlangen 91054, Germany
| | - M Müller
- Department of Molecular Life Sciences, University of Zurich, Zurich 8057, Switzerland
- Neuroscience Center Zurich, University of Zurich, Zurich 8057, Switzerland
- University of Zurich Clinical Research Priority Program (CRPP) Praeclare – Personalized prenatal and reproductive medicine, Zurich 8006, Switzerland
- University of Zurich Research Priority Program (URPP) AdaBD: Adaptive Brain Circuits in Development and Learning, Zurich 8006, Switzerland
| | - A Rauch
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich 8952, Switzerland
- Neuroscience Center Zurich, University of Zurich, Zurich 8057, Switzerland
- University of Zurich Clinical Research Priority Program (CRPP) Praeclare – Personalized prenatal and reproductive medicine, Zurich 8006, Switzerland
- University of Zurich Research Priority Program (URPP) AdaBD: Adaptive Brain Circuits in Development and Learning, Zurich 8006, Switzerland
- University of Zurich Research Priority Program (URPP) ITINERARE: Innovative Therapies in Rare Diseases, Zurich 8006, Switzerland
- Zurich Center for Integrative Human Physiology, University of Zurich, Zurich 8057, Switzerland
- University Children's Hospital Zurich, University of Zurich, Zurich 8032, Switzerland
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17
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Hopkins CE, McCormick K, Brock T, Wood M, Ruggiero S, Mcbride K, Kim C, Lawson JA, Helbig I, Bainbridge MN. Clinical variants in Caenorhabditis elegans expressing human STXBP1 reveal a novel class of pathogenic variants and classify variants of uncertain significance. GENETICS IN MEDICINE OPEN 2023; 1:100823. [PMID: 38827422 PMCID: PMC11141691 DOI: 10.1016/j.gimo.2023.100823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Purpose Modeling disease variants in animals is useful for drug discovery, understanding disease pathology, and classifying variants of uncertain significance (VUS) as pathogenic or benign. Methods Using Clustered Regularly Interspaced Short Palindromic Repeats, we performed a Whole-gene Humanized Animal Model procedure to replace the coding sequence of the animal model's unc-18 ortholog with the coding sequence for the human STXBP1 gene. Next, we used Clustered Regularly Interspaced Short Palindromic Repeats to introduce precise point variants in the Whole-gene Humanized Animal Model-humanized STXBP1 locus from 3 clinical categories (benign, pathogenic, and VUS). Twenty-six phenotypic features extracted from video recordings were used to train machine learning classifiers on 25 pathogenic and 32 benign variants. Results Using multiple models, we were able to obtain a diagnostic sensitivity near 0.9. Twenty-three VUS were also interrogated and 8 of 23 (34.8%) were observed to be functionally abnormal. Interestingly, unsupervised clustering identified 2 distinct subsets of known pathogenic variants with distinct phenotypic features; both p.Tyr75Cys and p.Arg406Cys cluster away from other variants and show an increase in swim speed compared with hSTXBP1 worms. This leads to the hypothesis that the mechanism of disease for these 2 variants may differ from most STXBP1-mutated patients and may account for some of the clinical heterogeneity observed in the patient population. Conclusion We have demonstrated that automated analysis of a small animal system is an effective, scalable, and fast way to understand functional consequences of variants in STXBP1 and identify variant-specific intensities of aberrant activity suggesting a genotype-to-phenotype correlation is likely to occur in human clinical variations of STXBP1.
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Affiliation(s)
| | | | | | | | - Sarah Ruggiero
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA
- The Epilepsy NeuroGenetics Initiative (ENGIN), Children’s Hospital of Philadelphia, Philadelphia, PA
- Department of Biomedical and Health Informatics (DBHi), Children’s Hospital of Philadelphia, Philadelphia, PA
- University of Pennsylvania, Neuroscience Program, Philadelphia, PA
| | | | | | | | - Ingo Helbig
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA
- The Epilepsy NeuroGenetics Initiative (ENGIN), Children’s Hospital of Philadelphia, Philadelphia, PA
- Department of Biomedical and Health Informatics (DBHi), Children’s Hospital of Philadelphia, Philadelphia, PA
- University of Pennsylvania, Neuroscience Program, Philadelphia, PA
| | - Matthew N. Bainbridge
- Codified Genomics, LLC, Houston, TX
- Rady Children’s Institute for Genomic Medicine, San Diego, CA
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18
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Hatch RJ, Berecki G, Jancovski N, Li M, Rollo B, Jafar-Nejad P, Rigo F, Kaila K, Reid CA, Petrou S. Carbogen-Induced Respiratory Acidosis Blocks Experimental Seizures by a Direct and Specific Inhibition of Na V1.2 Channels in the Axon Initial Segment of Pyramidal Neurons. J Neurosci 2023; 43:1658-1667. [PMID: 36732074 PMCID: PMC10010452 DOI: 10.1523/jneurosci.1387-22.2022] [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: 07/18/2022] [Revised: 11/01/2022] [Accepted: 12/05/2022] [Indexed: 02/04/2023] Open
Abstract
Brain pH is a critical factor for determining neuronal activity, with alkalosis increasing and acidosis reducing excitability. Acid shifts in brain pH through the breathing of carbogen (5% CO2/95% O2) reduces seizure susceptibility in animal models and patients. The molecular mechanisms underlying this seizure protection remain to be fully elucidated. Here, we demonstrate that male and female mice exposed to carbogen are fully protected from thermogenic-triggered seizures. Whole-cell patch-clamp recordings revealed that acid shifts in extracellular pH (pHo) significantly reduce action potential firing in CA1 pyramidal neurons but did not alter firing in hippocampal inhibitory interneurons. In real-time dynamic clamp experiments, acidification reduced simulated action potential firing generated in hybrid model neurons expressing the excitatory neuron predominant NaV1.2 channel. Conversely, acidification had no effect on action potential firing in hybrid model neurons expressing the interneuron predominant NaV1.1 channel. Furthermore, knockdown of Scn2a mRNA in vivo using antisense oligonucleotides reduced the protective effects of carbogen on seizure susceptibility. Both carbogen-mediated seizure protection and the reduction in CA1 pyramidal neuron action potential firing by low pHo were maintained in an Asic1a knock-out mouse ruling out this acid-sensing channel as the underlying molecular target. These data indicate that the acid-mediated reduction in excitatory neuron firing is mediated, at least in part, through the inhibition of NaV1.2 channels, whereas inhibitory neuron firing is unaffected. This reduction in pyramidal neuron excitability is the likely basis of seizure suppression caused by carbogen-mediated acidification.SIGNIFICANCE STATEMENT Brain pH has long been known to modulate neuronal excitability. Here, we confirm that brain acidification reduces seizure susceptibility in a mouse model of thermogenic seizures. Extracellular acidification reduced excitatory pyramidal neuron firing while having no effect on interneuron firing. Acidification also reduced dynamic clamp firing in cells expressing the NaV1.2 channel but not in cells expressing NaV1.1 channels. In vivo knockdown of Scn2a mRNA reduced seizure protection of acidification. In contrast, acid-mediated seizure protection was maintained in the Asic1a knock-out mouse. These data suggest NaV1.2 channel as an important target for acid-mediated seizure protection. Our results have implications on how natural variations in pH can modulate neuronal excitability and highlight potential antiseizure drug development strategies based on the NaV1.2 channel.
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Affiliation(s)
- Robert J Hatch
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Géza Berecki
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Nikola Jancovski
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Melody Li
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Ben Rollo
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | | | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, California 92008
| | - Kai Kaila
- Molecular and Integrative Biosciences and Neuroscience Center, University of Helsinki, 00014 Helsinki, Finland
| | - Christopher A Reid
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Steven Petrou
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria 3052, Australia
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19
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Nott E, Behl KE, Brambilla I, Green TE, Lucente M, Vavassori R, Watson A, Dalla Bernardina B, Hildebrand MS. Rare. The importance of research, analysis, reporting and education in 'solving' the genetic epilepsies: A perspective from the European patient advocacy group for EpiCARE. Eur J Med Genet 2023; 66:104680. [PMID: 36623768 DOI: 10.1016/j.ejmg.2022.104680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 11/14/2022] [Accepted: 12/11/2022] [Indexed: 01/09/2023]
Affiliation(s)
- E Nott
- European Patient Advocacy Group (ePAG) EpiCARE, France; Hope for Hypothalamic Hamartomas and Hope for Hypothalamic Hamartomas-UK, UK.
| | - K E Behl
- Alternating Hemiplegia of Childhood UK (AHCUK) and Alternating Hemiplegia of Childhood Federation of Europe (AHCFE), UK
| | - I Brambilla
- European Patient Advocacy Group (ePAG) EpiCARE, France; Dravet Italia Onlus; Epilepsy Research Centre, Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, 3084, Australia
| | - T E Green
- Epilepsy Research Centre, Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, 3084, Australia; Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, Victoria, 3052, Australia
| | - M Lucente
- European Patient Advocacy Group (ePAG) EpiCARE, France; Associazione Italiana GLUT1 Onlus, Italy
| | - R Vavassori
- European Patient Advocacy Group (ePAG) EpiCARE, France; International Alternating Hemiplegia of Childhood Research Consortium (IAHCRC), USA; Alternating Hemiplegia of Childhood 18+ (AHC18+ e.V.) Association, Germany
| | - A Watson
- European Patient Advocacy Group (ePAG) EpiCARE, France; Ring20 Research and Support UK, UK
| | - B Dalla Bernardina
- Dravet Italia Onlus; Research Center for Pediatric Epilepsies Verona, Department of Surgical Sciences, Dentistry, Gynecology and Pediatrics, University of Verona, Italy
| | - M S Hildebrand
- Hope for Hypothalamic Hamartomas and Hope for Hypothalamic Hamartomas-UK, UK; Epilepsy Research Centre, Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, 3084, Australia; Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, Victoria, 3052, Australia
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20
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Nanomedicine based strategies for oligonucleotide traversion across the blood-brain barrier. J Control Release 2023; 354:554-571. [PMID: 36649742 DOI: 10.1016/j.jconrel.2023.01.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 01/19/2023]
Abstract
Neurological disorders are considered the most prominent cause of disability worldwide. The major hurdle in the management of neurological disorders is the existence of the blood-brain barrier (BBB), which hinders the entry of several therapeutic moieties. In recent years, oligonucleotides have gained tremendous attention for their target specificity, diminished dose and adverse effects, thereby halting disease progression. However, enzymatic degradation, rapid clearance, limited circulation and availability at the bio-active site, etc., limit its clinical translation. Nanomedicine has opened up a breadth of opportunities in the delivery of oligonucleotides across the BBB. This review addresses the pitfalls associated with oligonucleotide delivery in traversing the BBB via nanotherapeutics for the management of brain disorders. Regulatory perspectives pertaining to hastening the clinical translation of oligonucleotide-loaded nanocarriers for brain delivery have been highlighted.
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21
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Müller P, Lerche H. [Gene Therapy for Epilepsy: Clinical Studies are on the Road]. FORTSCHRITTE DER NEUROLOGIE-PSYCHIATRIE 2023; 91:135-140. [PMID: 36716773 DOI: 10.1055/a-1995-5405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
For more than 10 years, research has been conducted on gene therapies for the most severe forms of epilepsy, which until now have proven resistant to treatment. First gene therapies are now in clinical trials for pharmacoresistant focal epilepsies and Dravet syndrome. In this article, we describe how these and many more gene therapies work and what they target.
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Affiliation(s)
- Peter Müller
- Abteilung Neurologie mit Schwerpunkt Epileptologie, Hertie Institute für klinische Hirnforschung, Universität Tübingen
| | - Holger Lerche
- Abteilung Neurologie mit Schwerpunkt Epileptologie, Hertie Institute für klinische Hirnforschung, Universität Tübingen
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22
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Burbano LE, Li M, Jancovski N, Jafar-Nejad P, Richards K, Sedo A, Soriano A, Rollo B, Jia L, Gazina EV, Piltz S, Adikusuma F, Thomas PQ, Kopsidas H, Rigo F, Reid CA, Maljevic S, Petrou S. Antisense oligonucleotide therapy for KCNT1 encephalopathy. JCI Insight 2022; 7:146090. [PMID: 36173683 PMCID: PMC9746904 DOI: 10.1172/jci.insight.146090] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 09/27/2022] [Indexed: 01/12/2023] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are characterized by pharmaco-resistant seizures with concomitant intellectual disability. Epilepsy of infancy with migrating focal seizures (EIMFS) is one of the most severe of these syndromes. De novo variants in ion channels, including gain-of-function variants in KCNT1, which encodes for sodium activated potassium channel protein KNa1.1, have been found to play a major role in the etiology of EIMFS. Here, we test a potential precision therapeutic approach in KCNT1-associated DEE using a gene-silencing antisense oligonucleotide (ASO) approach. We generated a mouse model carrying the KCNT1 p.P924L pathogenic variant; only the homozygous animals presented with the frequent, debilitating seizures and developmental compromise that are seen in patients. After a single intracerebroventricular bolus injection of a Kcnt1 gapmer ASO in symptomatic mice at postnatal day 40, seizure frequency was significantly reduced, behavioral abnormalities improved, and overall survival was extended compared with mice treated with a control ASO (nonhybridizing sequence). ASO administration at neonatal age was also well tolerated and effective in controlling seizures and extending the life span of treated animals. The data presented here provide proof of concept for ASO-based gene silencing as a promising therapeutic approach in KCNT1-associated epilepsies.
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Affiliation(s)
- Lisseth Estefania Burbano
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Melody Li
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Nikola Jancovski
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Kay Richards
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Alicia Sedo
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Ben Rollo
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Linghan Jia
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Elena V. Gazina
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Sandra Piltz
- School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Fatwa Adikusuma
- School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Paul Q. Thomas
- School of Medicine, University of Adelaide, Adelaide, South Australia, Australia.,South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Helen Kopsidas
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, California, USA
| | - Christopher A. Reid
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Snezana Maljevic
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.,Praxis Precision Medicines, Cambridge, Massachusetts, USA
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23
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Chen GT, Geschwind DH. Challenges and opportunities for precision medicine in neurodevelopmental disorders. Adv Drug Deliv Rev 2022; 191:114564. [PMID: 36183905 PMCID: PMC10409256 DOI: 10.1016/j.addr.2022.114564] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 09/20/2022] [Accepted: 09/24/2022] [Indexed: 01/24/2023]
Abstract
Neurodevelopmental Disorders (NDDs) encompass a broad spectrum of disorders, linked because of their origins in brain developmental processes, including diverse conditions across the age span, including autism spectrum disorders (ASD) and schizophrenia (SCZ). Clinical treatment of these disorders has traditionally focused on symptom management, as the severity of developmental disruption varies widely and the precise molecular mechanisms, timing, and progression of these disorders is usually not known. Several hundred genes have been identified as major risk factors for ASD and SCZ, which creates new potential therapeutic avenues, and there is strong evidence that these genes converge upon key molecular pathways, pointing to opportunities for precision medicine. In this review, we focus on forms of ASD and SCZ with known genetic etiologies and discuss advances in research technologies that enable a more systemic understanding of disease progression. We highlight recent advances in targeted clinical treatment and discuss ongoing preclinical efforts as well as new initiatives aimed at developing scalable platforms for NDD precision medicine.
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Affiliation(s)
- George T Chen
- Department of Neurology, David Geffen School of Medicine, UCLA, United States; Center for Autism Research and Treatment, Semel Institute, David Geffen School of Medicine, UCLA, United States
| | - Daniel H Geschwind
- Department of Neurology, David Geffen School of Medicine, UCLA, United States; Center for Autism Research and Treatment, Semel Institute, David Geffen School of Medicine, UCLA, United States; Department of Psychiatry and Biobehavioral Sciences, Semel Institute, David Geffen School of Medicine, UCLA, United States; Department of Human Genetics, David Geffen School of Medicine, UCLA, United States; Institute of Precision Health, UCLA, United States.
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24
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Amanat M, Nemeth CL, Fine AS, Leung DG, Fatemi A. Antisense Oligonucleotide Therapy for the Nervous System: From Bench to Bedside with Emphasis on Pediatric Neurology. Pharmaceutics 2022; 14:2389. [PMID: 36365206 PMCID: PMC9695718 DOI: 10.3390/pharmaceutics14112389] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 10/26/2022] [Accepted: 11/02/2022] [Indexed: 09/05/2023] Open
Abstract
Antisense oligonucleotides (ASOs) are disease-modifying agents affecting protein-coding and noncoding ribonucleic acids. Depending on the chemical modification and the location of hybridization, ASOs are able to reduce the level of toxic proteins, increase the level of functional protein, or modify the structure of impaired protein to improve function. There are multiple challenges in delivering ASOs to their site of action. Chemical modifications in the phosphodiester bond, nucleotide sugar, and nucleobase can increase structural thermodynamic stability and prevent ASO degradation. Furthermore, different particles, including viral vectors, conjugated peptides, conjugated antibodies, and nanocarriers, may improve ASO delivery. To date, six ASOs have been approved by the US Food and Drug Administration (FDA) in three neurological disorders: spinal muscular atrophy, Duchenne muscular dystrophy, and polyneuropathy caused by hereditary transthyretin amyloidosis. Ongoing preclinical and clinical studies are assessing the safety and efficacy of ASOs in multiple genetic and acquired neurological conditions. The current review provides an update on underlying mechanisms, design, chemical modifications, and delivery of ASOs. The administration of FDA-approved ASOs in neurological disorders is described, and current evidence on the safety and efficacy of ASOs in other neurological conditions, including pediatric neurological disorders, is reviewed.
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Affiliation(s)
- Man Amanat
- Moser Center for Leukodystrophies, Kennedy Krieger Institute, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Christina L. Nemeth
- Moser Center for Leukodystrophies, Kennedy Krieger Institute, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Amena Smith Fine
- Moser Center for Leukodystrophies, Kennedy Krieger Institute, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Doris G. Leung
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Center for Genetic Muscle Disorders, Kennedy Krieger Institute, Baltimore, MD 21205, USA
| | - Ali Fatemi
- Moser Center for Leukodystrophies, Kennedy Krieger Institute, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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25
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Brun L, Viemari J, Villard L. Mouse models of Kcnq2 dysfunction. Epilepsia 2022; 63:2813-2826. [PMID: 36047730 PMCID: PMC9828481 DOI: 10.1111/epi.17405] [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: 06/17/2022] [Revised: 08/29/2022] [Accepted: 08/30/2022] [Indexed: 01/12/2023]
Abstract
Variants in the Kv7.2 channel subunit encoded by the KCNQ2 gene cause epileptic disorders ranging from a benign form with self-limited epileptic seizures and normal development to severe forms with intractable epileptic seizures and encephalopathy. The biological mechanisms involved in these neurological diseases are still unclear. The disease remains intractable in patients affected by the severe form. Over the past 20 years, KCNQ2 models have been developed to elucidate pathological mechanisms and to identify new therapeutic targets. The diversity of Kcnq2 mouse models has proven invaluable to access neuronal networks and evaluate the associated cognitive deficits. This review summarizes the available models and their contribution to our current understanding of KCNQ2 epileptic disorders.
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Affiliation(s)
- Lucile Brun
- Aix Marseille Univ, Inserm, MMGMarseilleFrance
| | | | - Laurent Villard
- Aix Marseille Univ, Inserm, MMGMarseilleFrance,Service de Génétique Médicale, AP‐HM, Hôpital de La TimoneMarseilleFrance
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26
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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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27
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Goodspeed K, Bailey RM, Prasad S, Sadhu C, Cardenas JA, Holmay M, Bilder DA, Minassian BA. Gene Therapy: Novel Approaches to Targeting Monogenic Epilepsies. Front Neurol 2022; 13:805007. [PMID: 35847198 PMCID: PMC9284605 DOI: 10.3389/fneur.2022.805007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 04/20/2022] [Indexed: 11/18/2022] Open
Abstract
Genetic epilepsies are a spectrum of disorders characterized by spontaneous and recurrent seizures that can arise from an array of inherited or de novo genetic variants and disrupt normal brain development or neuronal connectivity and function. Genetically determined epilepsies, many of which are due to monogenic pathogenic variants, can result in early mortality and may present in isolation or be accompanied by neurodevelopmental disability. Despite the availability of more than 20 antiseizure medications, many patients with epilepsy fail to achieve seizure control with current therapies. Patients with refractory epilepsy—particularly of childhood onset—experience increased risk for severe disability and premature death. Further, available medications inadequately address the comorbid developmental disability. The advent of next-generation gene sequencing has uncovered genetic etiologies and revolutionized diagnostic practices for many epilepsies. Advances in the field of gene therapy also present the opportunity to address the underlying mechanism of monogenic epilepsies, many of which have only recently been described due to advances in precision medicine and biology. To bring precision medicine and genetic therapies closer to clinical applications, experimental animal models are needed that replicate human disease and reflect the complexities of these disorders. Additionally, identifying and characterizing clinical phenotypes, natural disease course, and meaningful outcome measures from epileptic and neurodevelopmental perspectives are necessary to evaluate therapies in clinical studies. Here, we discuss the range of genetically determined epilepsies, the existing challenges to effective clinical management, and the potential role gene therapy may play in transforming treatment options available for these conditions.
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Affiliation(s)
- Kimberly Goodspeed
- Division of Child Neurology, Department of Pediatrics, University of Texas Southwestern, Dallas, TX, United States
| | - Rachel M. Bailey
- Division of Child Neurology, Department of Pediatrics, University of Texas Southwestern, Dallas, TX, United States
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern, Dallas, TX, United States
| | - Suyash Prasad
- Department of Research and Development, Taysha Gene Therapies, Dallas, TX, United States
| | - Chanchal Sadhu
- Department of Research and Development, Taysha Gene Therapies, Dallas, TX, United States
| | - Jessica A. Cardenas
- Department of Research and Development, Taysha Gene Therapies, Dallas, TX, United States
| | - Mary Holmay
- Department of Research and Development, Taysha Gene Therapies, Dallas, TX, United States
| | - Deborah A. Bilder
- Division of Child and Adolescent Psychiatry, Department of Psychiatry, Huntsman Mental Health Institute, University of Utah, Salt Lake City, UT, United States
| | - Berge A. Minassian
- Division of Child Neurology, Department of Pediatrics, University of Texas Southwestern, Dallas, TX, United States
- *Correspondence: Berge A. Minassian
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28
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Morris G, Langa E, Fearon C, Conboy K, Lau E-How K, Sanz-Rodriguez A, O'Brien DF, Sweeney K, Lacey A, Delanty N, Beausang A, Brett FM, Cryan JB, Cunningham MO, Henshall DC. MicroRNA inhibition using antimiRs in acute human brain tissue sections. Epilepsia 2022; 63:e92-e99. [PMID: 35656590 PMCID: PMC9546319 DOI: 10.1111/epi.17317] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 06/01/2022] [Accepted: 06/01/2022] [Indexed: 11/30/2022]
Abstract
Antisense inhibition of microRNAs is an emerging preclinical approach to pharmacoresistant epilepsy. A leading candidate is an 'antimiR' targeting microRNA-134 (miR-134), but testing to date has used rodent models. Here, we develop an antimiR testing platform in human brain tissue sections. Brain specimens were obtained from patients undergoing resective surgery to treat pharmacoresistant epilepsy. Neocortical specimens were submerged in modified artificial cerebrospinal fluid (ACSF), dissected for clinical neuropathological examination, and unused material transferred for sectioning. Individual sections were incubated in oxygenated ACSF, containing either antimiR-134 or a non-targeting control antimiR, for 24 hours at room temperature. RNA integrity was assessed using BioAnalyzer processing, and individual miRNA levels measured using RT-qPCR. Specimens transported in ACSF could be used for neuropathological diagnosis and had good RNA integrity. AntimiR-134 mediated a dose-dependent knockdown of miR-134, with approximately 75% reduction of miR-134 at 1 µM and 90% reduction at 3 µM. These doses did not have off-target effects on expression of a selection of three other miRNAs. This is the first demonstration of antimiR-134 effects in live human brain tissues. The findings lend further support to the preclinical development of a therapy that targets miR-134 and offer a flexible platform for the pre-clinical testing of antimiRs, and other antisense oligonucleotide therapeutics, in human brain.
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Affiliation(s)
- Gareth Morris
- Neuroscience, Physiology and Pharmacology, University College London, United Kingdom.,Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences
| | - Elena Langa
- Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences
| | - Conor Fearon
- Department of Neuropathology, Beaumont Hospital, Dublin, Ireland.,Dublin Neurological Institute, Mater Misericordiae University Hospital, Eccles Street, Dublin, Ireland
| | - Karen Conboy
- Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences
| | - Kelvin Lau E-How
- Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences
| | - Amaya Sanz-Rodriguez
- Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences
| | | | - Kieron Sweeney
- Department of Neurosurgery, Beaumont Hospital, Dublin, Ireland
| | - Austin Lacey
- FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences.,The National Epilepsy Programme, Beaumont Hospital, Dublin, Ireland.,Discipline of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Norman Delanty
- Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences.,The National Epilepsy Programme, Beaumont Hospital, Dublin, Ireland
| | - Alan Beausang
- Department of Neuropathology, Beaumont Hospital, Dublin, Ireland
| | | | - Jane B Cryan
- Department of Neuropathology, Beaumont Hospital, Dublin, Ireland
| | - Mark O Cunningham
- FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences.,Discipline of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - David C Henshall
- Department of Physiology and Medical Physics, RCSI University of Medicine & Health Sciences, Dublin, Ireland.,FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine & Health Sciences
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McGinn RJ, Von Stein EL, Summers Stromberg JE, Li Y. Precision medicine in epilepsy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 190:147-188. [DOI: 10.1016/bs.pmbts.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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