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Jiao D, Xu L, Gu Z, Yan H, Shen D, Gu X. Pathogenesis, diagnosis, and treatment of epilepsy: electromagnetic stimulation-mediated neuromodulation therapy and new technologies. Neural Regen Res 2025; 20:917-935. [PMID: 38989927 PMCID: PMC11438347 DOI: 10.4103/nrr.nrr-d-23-01444] [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: 08/28/2023] [Revised: 10/31/2023] [Accepted: 01/18/2024] [Indexed: 07/12/2024] Open
Abstract
Epilepsy is a severe, relapsing, and multifactorial neurological disorder. Studies regarding the accurate diagnosis, prognosis, and in-depth pathogenesis are crucial for the precise and effective treatment of epilepsy. The pathogenesis of epilepsy is complex and involves alterations in variables such as gene expression, protein expression, ion channel activity, energy metabolites, and gut microbiota composition. Satisfactory results are lacking for conventional treatments for epilepsy. Surgical resection of lesions, drug therapy, and non-drug interventions are mainly used in clinical practice to treat pain associated with epilepsy. Non-pharmacological treatments, such as a ketogenic diet, gene therapy for nerve regeneration, and neural regulation, are currently areas of research focus. This review provides a comprehensive overview of the pathogenesis, diagnostic methods, and treatments of epilepsy. It also elaborates on the theoretical basis, treatment modes, and effects of invasive nerve stimulation in neurotherapy, including percutaneous vagus nerve stimulation, deep brain electrical stimulation, repetitive nerve electrical stimulation, in addition to non-invasive transcranial magnetic stimulation and transcranial direct current stimulation. Numerous studies have shown that electromagnetic stimulation-mediated neuromodulation therapy can markedly improve neurological function and reduce the frequency of epileptic seizures. Additionally, many new technologies for the diagnosis and treatment of epilepsy are being explored. However, current research is mainly focused on analyzing patients' clinical manifestations and exploring relevant diagnostic and treatment methods to study the pathogenesis at a molecular level, which has led to a lack of consensus regarding the mechanisms related to the disease.
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Affiliation(s)
- Dian Jiao
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Lai Xu
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Zhen Gu
- Key Laboratory of Advanced Drug Delivery Systems of Zhejiang Province, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Hua Yan
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Dingding Shen
- Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Xiaosong Gu
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
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Jones SP, O'Neill N, Carpenter JC, Muggeo S, Colasante G, Kullmann DM, Lignani G. Early developmental alterations of CA1 pyramidal cells in Dravet syndrome. Neurobiol Dis 2024; 201:106688. [PMID: 39368670 DOI: 10.1016/j.nbd.2024.106688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 08/21/2024] [Accepted: 09/29/2024] [Indexed: 10/07/2024] Open
Abstract
Dravet Syndrome (DS) is most often caused by heterozygous loss-of-function mutations in the voltage-gated sodium channel gene SCN1A (Nav1.1), resulting in severe epilepsy and neurodevelopmental impairment thought to be cause by reduced interneuron excitability. However, recent studies in mouse models suggest that interneuron dysfunction alone does not completely explain all the cellular and network impairments seen in DS. Here, we investigated the development of the intrinsic, synaptic, and network properties of CA1 pyramidal cells in a DS model prior to the appearance of overt seizures. We report that CA1 pyramidal cell development is altered by heterozygous reduction of Scn1a, and propose that this is explained by a period of reduced intrinsic excitability in early postnatal life, during which Scn1a is normally expressed in hippocampal pyramidal cells. We also use a novel ex vivo model of homeostatic plasticity to show an instability in homeostatic response during DS epileptogenesis. This study provides evidence for the early effects of Scn1a haploinsufficiency in pyramidal cells in contributing to the pathophysiology of DS.
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Affiliation(s)
- Steffan P Jones
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK
| | - Nathanael O'Neill
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK
| | - Jenna C Carpenter
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK
| | - Sharon Muggeo
- San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan, Italy
| | - Gaia Colasante
- San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan, Italy
| | - Dimitri M Kullmann
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK
| | - Gabriele Lignani
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK.
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Dong R, Jin R, Zhang H, Zhang H, Xue M, Li Y, Zhang K, Lv Y, Li X, Liu Y, Gai Z. Genotypic and phenotypic characteristics of sodium channel-associated epilepsy in Chinese population. J Hum Genet 2024; 69:441-453. [PMID: 38880818 DOI: 10.1038/s10038-024-01257-2] [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: 12/10/2023] [Revised: 04/27/2024] [Accepted: 04/30/2024] [Indexed: 06/18/2024]
Abstract
Variants in voltage-gated sodium channel (VGSC) genes are implicated in seizures, epilepsy, and neurodevelopmental disorders, constituting a significant aspect of hereditary epilepsy in the Chinese population. Through retrospective analysis utilizing next-generation sequencing (NGS), we examined the genotypes and phenotypes of VGSC-related epilepsy cases from a cohort of 691 epilepsy subjects. Our findings revealed that 5.1% of subjects harbored VGSC variants, specifically 22 with SCN1A, 9 with SCN2A, 1 with SCN8A, and 3 with SCN1B variants; no SCN3A variants were detected. Among these, 14 variants were previously reported, while 21 were newly identified. SCN1A variant carriers predominantly presented with Dravet Syndrome (DS) and Genetic Epilepsy with Febrile Seizures Plus (GEFS + ), featuring a heightened sensitivity to fever-induced seizures. Statistically significant disparities emerged between the SCN1A-DS and SCN1A-GEFS+ groups concerning seizure onset and genetic diagnosis age, incidence of status epilepticus, mental retardation, anti-seizure medication (ASM) responsiveness, and familial history. Notably, subjects with SCN1A variants affecting the protein's pore region experienced more frequent cluster seizures. All SCN2A variants were of de novo origin, and 88.9% of individuals with SCN2A variations exhibited cluster seizures. This research reveals a significant association between variations in VGSC-related genes and the clinical phenotype diversity of epilepsy subjects in China, emphasizing the pivotal role of NGS screening in establishing accurate disease diagnoses and guiding the selection of ASM.
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Affiliation(s)
- Rui Dong
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Ruifeng Jin
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
- Department of neurology, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
| | - Hongwei Zhang
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
- Department of neurology, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
| | - Haiyan Zhang
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Min Xue
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Yue Li
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Kaihui Zhang
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Yuqiang Lv
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
| | - Xiaoying Li
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China.
- Neonatology department, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China.
| | - Yi Liu
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China.
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China.
| | - Zhongtao Gai
- Pediatric Research Institute, Children's Hospital Affiliated to Shandong University (Jinan Children's Hospital), Jinan, China
- Shandong Provincial Clinical Research Center for Children's Health and Disease, Jinan, China
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Shiota Y, Nishiyama T, Yokoyama S, Yoshimura Y, Hasegawa C, Tanaka S, Iwasaki S, Kikuchi M. Association of genetic variants with autism spectrum disorder in Japanese children revealed by targeted sequencing. Front Genet 2024; 15:1352480. [PMID: 39280100 PMCID: PMC11395840 DOI: 10.3389/fgene.2024.1352480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/04/2024] [Indexed: 09/18/2024] Open
Abstract
Introduction Autism spectrum disorders (ASD) represent a heterogeneous group of neurodevelopmental disorders with strong genetic predispositions. Although an increasing number of genetic variants have been implicated in the pathogenesis of ASD, little is known about the relationship between ASD-associated genetic variants and individual ASD traits. Therefore, we aimed to investigate these relationships. Methods Here, we report a case-control association study of 32 Japanese children with ASD (mainly with high-functioning autism [HFA]) and 36 with typical development (TD). We explored previously established ASD-associated genes using a next-generation sequencing panel and determined the association between Social Responsiveness Scale (SRS) T-scores and intelligence quotient (IQ) scores. Results In the genotype-phenotype analyses, 40 variants of five genes (SCN1A, SHANK3, DYRK1A, CADPS, and SCN2A) were associated with ASD/TD phenotypes. In particular, 10 SCN1A variants passed permutation filtering (false discovery rate <0.05). In the quantitative association analyses, 49 variants of 12 genes (CHD8, SCN1A, SLC6A1, KMT5B, CNTNAP2, KCNQ3, SCN2A, ARID1B, SHANK3, DYRK1A, FOXP1, and GRIN2B) and 50 variants of 10 genes (DYRK1A, SCN2A, SLC6A1, ARID1B, CNTNAP2, SHANK3, FOXP1, PTEN, SCN1A, and CHD8) were associated with SRS T- and IQ-scores, respectively. Conclusion Our data suggest that these identified variants are essential for the genetic architecture of HFA.
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Affiliation(s)
- Yuka Shiota
- Japan Society for the Promotion of Science, Tokyo, Japan
- Research Center for Child Mental Development, Kanazawa University, Kanazawa, Japan
| | - Tomoaki Nishiyama
- Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, Japan
| | - Shigeru Yokoyama
- Research Center for Child Mental Development, Kanazawa University, Kanazawa, Japan
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Kanazawa, Japan
| | - Yuko Yoshimura
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Kanazawa, Japan
- Institute of Human and Social Sciences, Kanazawa University, Kanazawa, Japan
| | - Chiaki Hasegawa
- Research Center for Child Mental Development, Kanazawa University, Kanazawa, Japan
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Kanazawa, Japan
| | - Sanae Tanaka
- Research Center for Child Mental Development, Kanazawa University, Kanazawa, Japan
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Kanazawa, Japan
| | - Sumie Iwasaki
- Japan Society for the Promotion of Science, Tokyo, Japan
- Institute of Human and Social Sciences, Kanazawa University, Kanazawa, Japan
| | - Mitsuru Kikuchi
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Kanazawa, Japan
- Department of Psychiatry and Neurobiology, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
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Shpun G, Markus A, Farah N, Zalevsky Z, Mandel Y. Adhesion of retinal cells to gold surfaces by biomimetic molecules. Front Cell Dev Biol 2024; 12:1438716. [PMID: 39263323 PMCID: PMC11387177 DOI: 10.3389/fcell.2024.1438716] [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: 05/26/2024] [Accepted: 08/15/2024] [Indexed: 09/13/2024] Open
Abstract
Background Neural cell-electrode coupling is crucial for effective neural and retinal prostheses. Enhancing this coupling can be achieved through surface modification and geometrical design to increase neuron-electrode proximity. In the current research, we focused on designing and studying various biomolecules as a method to elicit neural cell-electrode adhesion via cell-specific integrin mechanisms. Methods We designed extracellular matrix biomimetic molecules with different head sequences (RGD or YIGSR), structures (linear or cyclic), and spacer lengths (short or long). These molecules, anchored by a thiol (SH) group, were deposited onto gold surfaces at various concentrations. We assessed the modifications using contact angle measurements, fluorescence imaging, and X-ray Photoelectron Spectroscopy (XPS). We then analyzed the adhesion of retinal cells and HEK293 cells to the modified surfaces by measuring cell density, surface area, and focal adhesion spots, and examined changes in adhesion-related gene and integrin expression. Results Results showed that YIGSR biomolecules significantly enhanced retinal cell adhesion, regardless of spacer length. For HEK293 cells, RGD biomolecules were more effective, especially with cyclic RGD and long spacers. Both cell types showed increased expression of specific adhesion integrins and proteins like vinculin and PTK2; these results were in agreement with the adhesion studies, confirming the cell-specific interactions with modified surfaces. Conclusion This study highlights the importance of tailored biomolecules for improving neural cell adhesion to electrodes. By customizing biomolecules to foster specific and effective interactions with adhesion integrins, our study provides valuable insights for enhancing the integration and functionality of retinal prostheses and other neural implants.
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Affiliation(s)
- Gal Shpun
- The Alexander Kofkin Faculty of Engineering, Bar Ilan University, Ramat Gan, Israel
- School of Optometry and Visual Science, Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, Israel
| | - Amos Markus
- School of Optometry and Visual Science, Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, Israel
| | - Nairouz Farah
- School of Optometry and Visual Science, Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, Israel
| | - Zeev Zalevsky
- The Alexander Kofkin Faculty of Engineering, Bar Ilan University, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, Israel
| | - Yossi Mandel
- School of Optometry and Visual Science, Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, Israel
- The Gonda Multidisciplinary Brain Research Centre, Bar-Ilan University, Ramat Gan, Israel
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Kim JH, Bae HG, Wu WC, Nip K, Gould E. SCN2A-linked myelination deficits and synaptic plasticity alterations drive auditory processing disorders in ASD. RESEARCH SQUARE 2024:rs.3.rs-4925935. [PMID: 39257993 PMCID: PMC11384822 DOI: 10.21203/rs.3.rs-4925935/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2024]
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by complex sensory processing deficits. A key unresolved question is how alterations in neural connectivity and communication translate into the behavioral manifestations seen in ASD. Here, we investigate how oligodendrocyte dysfunction alters myelin plasticity and neuronal activity, leading to auditory processing disorder associated with ASD. We focus on the SCN2A gene, an ASD-risk factor, to understand its role in myelination and neural processing within the auditory nervous system. Through transcriptional profiling, we identified alterations in the expression of myelin-associated genes in Scn2a conditional knockout mice, highlighting the cellular consequences engendered by Scn2a deletion in oligodendrocytes. The results reveal a nuanced interplay between oligodendrocytes and axons, where Scn2a deletion causes alterations in the intricate process of myelination. This disruption instigates changes in axonal properties, presynaptic excitability, and synaptic plasticity at the single cell level. Furthermore, oligodendrocyte-specific Scn2a deletion compromises the integrity of neural circuitry within auditory pathways, leading to auditory hypersensitivity. Our findings reveal a novel pathway linking myelin deficits to synaptic activity and sensory abnormalities in ASD.
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Gao Y, Shonai D, Trn M, Zhao J, Soderblom EJ, Garcia-Moreno SA, Gersbach CA, Wetsel WC, Dawson G, Velmeshev D, Jiang YH, Sloofman LG, Buxbaum JD, Soderling SH. Proximity analysis of native proteomes reveals phenotypic modifiers in a mouse model of autism and related neurodevelopmental conditions. Nat Commun 2024; 15:6801. [PMID: 39122707 PMCID: PMC11316102 DOI: 10.1038/s41467-024-51037-x] [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: 02/20/2024] [Accepted: 07/23/2024] [Indexed: 08/12/2024] Open
Abstract
One of the main drivers of autism spectrum disorder is risk alleles within hundreds of genes, which may interact within shared but unknown protein complexes. Here we develop a scalable genome-editing-mediated approach to target 14 high-confidence autism risk genes within the mouse brain for proximity-based endogenous proteomics, achieving the identification of high-specificity spatial proteomes. The resulting native proximity proteomes are enriched for human genes dysregulated in the brain of autistic individuals, and reveal proximity interactions between proteins from high-confidence risk genes with those of lower-confidence that may provide new avenues to prioritize genetic risk. Importantly, the datasets are enriched for shared cellular functions and genetic interactions that may underlie the condition. We test this notion by spatial proteomics and CRISPR-based regulation of expression in two autism models, demonstrating functional interactions that modulate mechanisms of their dysregulation. Together, these results reveal native proteome networks in vivo relevant to autism, providing new inroads for understanding and manipulating the cellular drivers underpinning its etiology.
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Affiliation(s)
- Yudong Gao
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Daichi Shonai
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
| | - Matthew Trn
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, USA
| | - Jieqing Zhao
- Department of Biology, Duke University, Durham, NC, USA
| | - Erik J Soderblom
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, USA
- Proteomics and Metabolomics Shared Resource, Duke University School of Medicine, Durham, NC, USA
| | | | - Charles A Gersbach
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, USA
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
- Center for Advanced Genomic Technologies, Duke University, Durham, NC, USA
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
| | - William C Wetsel
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, USA
- Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA
- Department of Neurobiology, Duke University School of Medicine, Durham, NC, USA
- Mouse Behavioral and Neuroendocrine Analysis Core Facility, Duke University School of Medicine, Durham, NC, USA
| | - Geraldine Dawson
- Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA
| | - Dmitry Velmeshev
- Department of Neurobiology, Duke University School of Medicine, Durham, NC, USA
| | - Yong-Hui Jiang
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut, USA
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Laura G Sloofman
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Joseph D Buxbaum
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Scott H Soderling
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, USA.
- Department of Neurobiology, Duke University School of Medicine, Durham, NC, USA.
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M K, M R, J B, A BI, K IP, R W, E O, A ZK, R S, R P. Neurodevelopmental disorder in a patient with HMBS and SCN3A variants-A possibly blended phenotype further delineating autosomal recessive HMBS related disease. Am J Med Genet A 2024; 194:e63617. [PMID: 38568055 DOI: 10.1002/ajmg.a.63617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 03/04/2024] [Accepted: 03/22/2024] [Indexed: 07/05/2024]
Abstract
Monoallelic pathogenic HMBS variants are a well-established cause of acute intermittent porphyria (AIP), whereas biallelic pathogenic variants may cause HMBS-related leukoencephalopathy which remains a poorly characterized disorder. We describe an 8-year-old girl with hypotonia, hearing impairment, horizontal nystagmus, bilateral strabismus, impaired visual acuity, and optic nerve atrophy. She had no epilepsy but sleep electroencephalogram showed paroxysmal changes in the right hemisphere with secondary generalizations. Brain magnetic resonance imaging was unremarkable apart from a few small white matter hyperintensities. Exome sequencing (ES) initially prioritized a SCN3A c.3822G>A de novo variant whose sole causative role was eventually questioned as not fully compatible with symptoms. ES reanalysis revealed a homozygous c.674G>A HMBS variant. In the monoallelic form this variant is a known cause of AIP, whereas in trans with another HMBS pathogenic variant it was associated with the HMBS-related leukoencephalopathy in four individuals. Despite lack of signs/symptoms of porphyria, literature analysis suggested that HMBS c.674G>A likely contributed to the disease either as the sole cause or together with SCN3A c.3822G>A as a part of blended phenotype. Our report adds to the relatively small number of described cases of HMBS-related leukoencephalopathy and emphasizes that autosomal recessive form of HMBS disease can be present in the absence of porphyria symptoms.
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Affiliation(s)
- Kłaniewska M
- Department of Family and Pediatric Nursing, Wroclaw Medical University, Wroclaw, Poland
| | - Rydzanicz M
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Bladowska J
- Department of Radiology, Wroclaw 4th Military Clinical Hospital, Faculty of Medicine, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Borys-Iwanicka A
- Department of Paediatrics, Gastroenterology and Nutrition, Wroclaw Medical University, Wroclaw, Poland
| | - Iwanicka-Pronicka K
- Department of Medical Genetics, The Children's Memorial Health Institute, Warsaw, Poland
| | - Wasilewski R
- Department of Disorders of Hemostasis and Internal Medicine, Institute of Hematology and Transfusion Medicine, Warsaw, Poland
| | - Odnoczko E
- Laboratory of Genetics in Hemostasis and Porphyria, Department of Hemostasis and Metabolic Disorders, Institute of Hematology and Transfusion Medicine, Warsaw, Poland
| | - Zubkiewicz-Kucharska A
- Department of Pediatrics, Endocrinology, Diabetology and Metabolic Diseases, Medical University of Wroclaw, Wroclaw, Poland
| | - Smigiel R
- Department of Pediatrics, Endocrinology, Diabetology and Metabolic Diseases, Medical University of Wroclaw, Wroclaw, Poland
| | - Ploski R
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
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Wang Y, Yang H, Li N, Wang L, Guo C, Ma W, Liu S, Peng C, Chen J, Song H, Chen H, Ma X, Yi J, Lian J, Kong W, Dong J, Tu X, Shah M, Tian X, Huang Z. A Novel Ubiquitin Ligase Adaptor PTPRN Suppresses Seizure Susceptibility through Endocytosis of Na V1.2 Sodium Channels. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400560. [PMID: 38874331 PMCID: PMC11304301 DOI: 10.1002/advs.202400560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/06/2024] [Indexed: 06/15/2024]
Abstract
Intrinsic plasticity, a fundamental process enabling neurons to modify their intrinsic properties, plays a crucial role in shaping neuronal input-output function and is implicated in various neurological and psychiatric disorders. Despite its importance, the underlying molecular mechanisms of intrinsic plasticity remain poorly understood. In this study, a new ubiquitin ligase adaptor, protein tyrosine phosphatase receptor type N (PTPRN), is identified as a regulator of intrinsic neuronal excitability in the context of temporal lobe epilepsy. PTPRN recruits the NEDD4 Like E3 Ubiquitin Protein Ligase (NEDD4L) to NaV1.2 sodium channels, facilitating NEDD4L-mediated ubiquitination, and endocytosis of NaV1.2. Knockout of PTPRN in hippocampal granule cells leads to augmented NaV1.2-mediated sodium currents and higher intrinsic excitability, resulting in increased seizure susceptibility in transgenic mice. Conversely, adeno-associated virus-mediated delivery of PTPRN in the dentate gyrus region decreases intrinsic excitability and reduces seizure susceptibility. Moreover, the present findings indicate that PTPRN exerts a selective modulation effect on voltage-gated sodium channels. Collectively, PTPRN plays a significant role in regulating intrinsic excitability and seizure susceptibility, suggesting a potential strategy for precise modulation of NaV1.2 channels' function.
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Affiliation(s)
- Yifan Wang
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Hui Yang
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Na Li
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Lili Wang
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Chang Guo
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Weining Ma
- Department of NeurologyShengjing Hospital Affiliated to China Medical UniversityShenyang110022China
| | - Shiqi Liu
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Chao Peng
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Jiexin Chen
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Huifang Song
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Hedan Chen
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Xinyue Ma
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Jingyun Yi
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Jingjing Lian
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Weikaixin Kong
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Jie Dong
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Xinyu Tu
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
| | - Mala Shah
- UCL School of PharmacyUniversity College LondonLondonWC1N 1AXUK
| | - Xin Tian
- Department of NeurologyThe First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqing400016China
| | - Zhuo Huang
- State Key Laboratory of Natural and Biomimetic DrugsDepartment of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking UniversityBeijing100191China
- IDG/McGovern Institute for Brain ResearchPeking UniversityBeijing100871China
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10
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Wu J, Zhang J, Chen X, Wettschurack K, Que Z, Deming BA, Olivero-Acosta MI, Cui N, Eaton M, Zhao Y, Li SM, Suzuki M, Chen I, Xiao T, Halurkar MS, Mandal P, Yuan C, Xu R, Koss WA, Du D, Chen F, Wu LJ, Yang Y. Microglial over-pruning of synapses during development in autism-associated SCN2A-deficient mice and human cerebral organoids. Mol Psychiatry 2024; 29:2424-2437. [PMID: 38499656 DOI: 10.1038/s41380-024-02518-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 02/29/2024] [Accepted: 03/04/2024] [Indexed: 03/20/2024]
Abstract
Autism spectrum disorder (ASD) is a major neurodevelopmental disorder affecting 1 in 36 children in the United States. While neurons have been the focus of understanding ASD, an altered neuro-immune response in the brain may be closely associated with ASD, and a neuro-immune interaction could play a role in the disease progression. As the resident immune cells of the brain, microglia regulate brain development and homeostasis via core functions including phagocytosis of synapses. While ASD has been traditionally considered a polygenic disorder, recent large-scale human genetic studies have identified SCN2A deficiency as a leading monogenic cause of ASD and intellectual disability. We generated a Scn2a-deficient mouse model, which displays major behavioral and neuronal phenotypes. However, the role of microglia in this disease model is unknown. Here, we reported that Scn2a-deficient mice have impaired learning and memory, accompanied by reduced synaptic transmission and lower spine density in neurons of the hippocampus. Microglia in Scn2a-deficient mice are partially activated, exerting excessive phagocytic pruning of post-synapses related to the complement C3 cascades during selective developmental stages. The ablation of microglia using PLX3397 partially restores synaptic transmission and spine density. To extend our findings from rodents to human cells, we established a microglia-incorporated human cerebral organoid model carrying an SCN2A protein-truncating mutation identified in children with ASD. We found that human microglia display increased elimination of post-synapse in cerebral organoids carrying the SCN2A mutation. Our study establishes a key role of microglia in multi-species autism-associated models of SCN2A deficiency from mouse to human cells.
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Affiliation(s)
- Jiaxiang Wu
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Jingliang Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Xiaoling Chen
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Kyle Wettschurack
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Zhefu Que
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Brody A Deming
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Maria I Olivero-Acosta
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Ningren Cui
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Muriel Eaton
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Yuanrui Zhao
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Sophia M Li
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Matthew Suzuki
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Ian Chen
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Tiange Xiao
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Manasi S Halurkar
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Purba Mandal
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Chongli Yuan
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Ranjie Xu
- College of Veterinary Medicine, Purdue University, West Lafayette, IN, 47907, USA
| | - Wendy A Koss
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Dongshu Du
- School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Fuxue Chen
- School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Yang Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA.
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA.
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11
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Berg AT, Thompson CH, Myers LS, Anderson E, Evans L, Kaiser AJE, Paltell K, Nili AN, DeKeyser JML, Abramova TV, Nesbitt G, Egan SM, Vanoye CG, George AL. Expanded clinical phenotype spectrum correlates with variant function in SCN2A-related disorders. Brain 2024; 147:2761-2774. [PMID: 38651838 PMCID: PMC11292900 DOI: 10.1093/brain/awae125] [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: 12/18/2023] [Revised: 03/04/2024] [Accepted: 03/24/2024] [Indexed: 04/25/2024] Open
Abstract
SCN2A-related disorders secondary to altered function in the voltage-gated sodium channel Nav1.2 are rare, with clinically heterogeneous expressions that include epilepsy, autism and multiple severe to profound impairments and other conditions. To advance understanding of the clinical phenotypes and their relationship to channel function, 81 patients (36 female, 44%, median age 5.4 years) with 69 unique SCN2A variants were systematically phenotyped and their Nav1.2 channel function systematically assessed. Participants were recruited through the FamileSCN2A Foundation. Primary phenotype (epilepsy of neonatal onset, n = 27; infant onset, n = 18; and later onset n = 24; and autism without seizures, n = 12) was strongly correlated with a non-seizure severity index (P = 0.002), which was based on presence of severe impairments in gross motor, fine motor, communication abilities, gastrostomy tube dependence and diagnosis of cortical visual impairment and scoliosis. Non-seizure severity was greatest in the neonatal-onset group and least in the autism group (P = 0.002). Children with the lowest severity indices were still severely impaired, as reflected by an average Vineland Adaptive Behavior composite score of 49.5 (>3 standard deviations below the norm-referenced mean of the test). Epileptic spasms were significantly more common in infant-onset (67%) than in neonatal (22%) or later-onset (29%) epilepsy (P = 0.007). Primary phenotype was also strongly correlated with variant function (P < 0.0001); gain-of-function and mixed function variants predominated in neonatal-onset epilepsy, shifting to moderate loss of function in infant-onset epilepsy and to severe and complete loss of function in later-onset epilepsy and autism groups. Exploratory cluster analysis identified five groups, representing: (i) primarily later-onset epilepsy with moderate loss-of-function variants and low severity indices; (ii) mostly infant-onset epilepsy with moderate loss-of-function variants but higher severity indices; and (iii) late-onset and autism only, with the lowest severity indices (mostly zero) and severe/complete loss-of-function variants. Two exclusively neonatal clusters were distinguished from each other largely on non-seizure severity scores and secondarily on variant function. The relationship between primary phenotype and variant function emphasizes the role of developmental factors in the differential clinical expression of SCN2A variants based on their effects on Nav1.2 channel function. The non-seizure severity of SCN2A disorders depends on a combination of the age at seizure onset (primary phenotype) and variant function. As precision therapies for SCN2A-related disorders advance towards clinical trials, knowledge of the relationship between variant function and clinical disease expression will be valuable for identifying appropriate patients for these trials and in selecting efficient clinical outcomes.
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Affiliation(s)
- Anne T Berg
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
- FamilieSCN2A Foundation, Longmeadow, MA 10116, USA
| | - Christopher H Thompson
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | | | - Erica Anderson
- Institute for Innovations in Developmental Sciences, Northwestern University, Chicago, IL 60611, USA
| | - Lindsey Evans
- Department of Psychology, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Ariela J E Kaiser
- Department of Psychology, University of Illinois Chicago, Chicago, IL 60616, USA
| | - Katherine Paltell
- Department of Psychology, University of Illinois Chicago, Chicago, IL 60616, USA
| | - Amanda N Nili
- Department of Medical and Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Jean-Marc L DeKeyser
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Tatiana V Abramova
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | | | - Shawn M Egan
- FamilieSCN2A Foundation, Longmeadow, MA 10116, USA
| | - Carlos G Vanoye
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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12
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Hudac CM, Dommer K, Mahony M, DesChamps TD, Cairney B, Earl R, Kurtz-Nelson EC, Bradshaw J, Bernier RA, Eichler EE, Neuhaus E, Webb SJ, Shic F. Visual and auditory attention in individuals with DYRK1A and SCN2A disruptive variants. Autism Res 2024. [PMID: 39080977 DOI: 10.1002/aur.3202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 07/17/2024] [Indexed: 08/02/2024]
Abstract
This preliminary study sought to assess biomarkers of attention using electroencephalography (EEG) and eye tracking in two ultra-rare monogenic populations associated with autism spectrum disorder (ASD). Relative to idiopathic ASD (n = 12) and neurotypical comparison (n = 49) groups, divergent attention profiles were observed for the monogenic groups, such that individuals with DYRK1A (n = 9) exhibited diminished auditory attention condition differences during an oddball EEG paradigm whereas individuals with SCN2A (n = 5) exhibited diminished visual attention condition differences noted by eye gaze tracking when viewing social interactions. Findings provide initial support for alignment of auditory and visual attention markers in idiopathic ASD and neurotypical development but not monogenic groups. These results support ongoing efforts to develop translational ASD biomarkers within the attention domain.
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Affiliation(s)
- Caitlin M Hudac
- Department of Psychology, University of South Carolina, Columbia, South Carolina, USA
- Center for Autism and Neurodevelopment (CAN) Research Center, University of South Carolina, Columbia, South Carolina, USA
- Institute for Mind and Brain, University of South Carolina, Columbia, South Carolina, USA
| | - Kelsey Dommer
- Center for Child Health, Behavior and Development, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Monique Mahony
- Center for Child Health, Behavior and Development, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Trent D DesChamps
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Brianna Cairney
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Rachel Earl
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | | | - Jessica Bradshaw
- Department of Psychology, University of South Carolina, Columbia, South Carolina, USA
- Center for Autism and Neurodevelopment (CAN) Research Center, University of South Carolina, Columbia, South Carolina, USA
- Institute for Mind and Brain, University of South Carolina, Columbia, South Carolina, USA
| | - Raphael A Bernier
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Evan E Eichler
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, Washington, USA
| | - Emily Neuhaus
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Sara Jane Webb
- Center for Child Health, Behavior and Development, Seattle Children's Research Institute, Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Frederick Shic
- Center for Child Health, Behavior and Development, Seattle Children's Research Institute, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
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13
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Senko K, Saddoris KL, Baus E, Soe K, Vaughn SE. Catatonia responsive to corticosteroids in a patient with an SCN2A variant. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2024:e32101. [PMID: 39056510 DOI: 10.1002/ajmg.c.32101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 07/07/2024] [Accepted: 07/12/2024] [Indexed: 07/28/2024]
Abstract
Variants in SCN2A are a known risk factor for developing autism spectrum disorder (ASD). Catatonia is a complex neuropsychiatric syndrome, which occurs at a higher rate in individuals with ASD. Catatonia has also been associated with COVID-19 infection, though the majority of these cases are associated with increased serum inflammatory markers. We present a case of a 15-year-old female with ASD and corticosteroid responsive stuporous catatonia to explore the relationship between SCN2A variants, ASD, COVID-19 exposure, and treatment refractory catatonia. Despite a lack of significantly elevated serum or CSF inflammatory markers, this patient showed significant improvement following initiation of corticosteroid therapy. This case presents a novel approach to the work-up and treatment of catatonia in individuals with SCN2A variants independent of elevated inflammatory markers.
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Affiliation(s)
- Kimberly Senko
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Child & Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Kelsey L Saddoris
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Child & Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Ella Baus
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Child & Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Katherine Soe
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Child & Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Samuel E Vaughn
- Division of Child & Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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14
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He G, Zheng Y, Chang S, Wang L, Yang X, Hao H, Li J, Zhang X, Tian F, Liang X, Xu H, Wang P, Chen X, Cao Z, Fang S, Gao Z, Liu H. Discovery of Novel Pyrimidine-Based Derivatives as Nav1.2 Inhibitors with Efficacy in Mouse Models of Epilepsy. J Med Chem 2024. [PMID: 39037114 DOI: 10.1021/acs.jmedchem.4c00861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
Dysfunction of voltage-gated sodium channel Nav1.2 causes various epileptic disorders, and inhibition of the channel has emerged as an attractive therapeutic strategy. However, currently available Nav1.2 inhibitors exhibit low potency and limited structural diversity. In this study, a novel series of pyrimidine-based derivatives with Nav1.2 inhibitory activity were designed, synthesized, and evaluated. Compounds 14 and 35 exhibited potent activity against Nav1.2, boasting IC50 values of 120 and 65 nM, respectively. Compound 14 displayed favorable pharmacokinetics (F = 43%) following intraperitoneal injection and excellent brain penetration potency (B/P = 3.6). Compounds 14 and 35 exhibited robust antiepileptic activities in the maximal electroshock test, with ED50 values of 3.2 and 11.1 mg/kg, respectively. Compound 35 also demonstrated potent antiepileptic activity in a 6 Hz (32 mA) model, with an ED50 value of 18.5 mg/kg. Overall, compounds 14 and 35 are promising leads for the development of new small-molecule therapeutics for epilepsy.
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Affiliation(s)
- Guoxue He
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yueming Zheng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shunzhen Chang
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Long Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- Pharmacophenomics Laboratory, Human Phenome Institute, Fudan University, Shanghai 201203, China
| | - Xiaohao Yang
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haishuang Hao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jiyuan Li
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Xian Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Fuyun Tian
- Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xuewu Liang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haiyan Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Pei Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xueqin Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Zeyu Cao
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sui Fang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Zhaobing Gao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hong Liu
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China
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15
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Silva DB, Trinidad M, Ljungdahl A, Revalde JL, Berguig GY, Wallace W, Patrick CS, Bomba L, Arkin M, Dong S, Estrada K, Hutchinson K, LeBowitz JH, Schlessinger A, Johannesen KM, Møller RS, Giacomini KM, Froelich S, Sanders SJ, Wuster A. Haploinsufficiency underlies the neurodevelopmental consequences of SLC6A1 variants. Am J Hum Genet 2024; 111:1222-1238. [PMID: 38781976 PMCID: PMC11179425 DOI: 10.1016/j.ajhg.2024.04.021] [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: 09/19/2023] [Revised: 04/26/2024] [Accepted: 04/26/2024] [Indexed: 05/25/2024] Open
Abstract
Heterozygous variants in SLC6A1, encoding the GAT-1 GABA transporter, are associated with seizures, developmental delay, and autism. The majority of affected individuals carry missense variants, many of which are recurrent germline de novo mutations, raising the possibility of gain-of-function or dominant-negative effects. To understand the functional consequences, we performed an in vitro GABA uptake assay for 213 unique variants, including 24 control variants. De novo variants consistently resulted in a decrease in GABA uptake, in keeping with haploinsufficiency underlying all neurodevelopmental phenotypes. Where present, ClinVar pathogenicity reports correlated well with GABA uptake data; the functional data can inform future reports for the remaining 72% of unscored variants. Surface localization was assessed for 86 variants; two-thirds of loss-of-function missense variants prevented GAT-1 from being present on the membrane while GAT-1 was on the surface but with reduced activity for the remaining third. Surprisingly, recurrent de novo missense variants showed moderate loss-of-function effects that reduced GABA uptake with no evidence for dominant-negative or gain-of-function effects. Using linear regression across multiple missense severity scores to extrapolate the functional data to all potential SLC6A1 missense variants, we observe an abundance of GAT-1 residues that are sensitive to substitution. The extent of this missense vulnerability accounts for the clinically observed missense enrichment; overlap with hypermutable CpG sites accounts for the recurrent missense variants. Strategies to increase the expression of the wild-type SLC6A1 allele are likely to be beneficial across neurodevelopmental disorders, though the developmental stage and extent of required rescue remain unknown.
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Affiliation(s)
- Dina Buitrago Silva
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Marena Trinidad
- BioMarin Pharmaceutical Inc., Novato, CA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Alicia Ljungdahl
- Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford OX3 7TY, UK
| | - Jezrael L Revalde
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
| | | | | | - Cory S Patrick
- Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | | | - Michelle Arkin
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
| | - Shan Dong
- Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | | | - Keino Hutchinson
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | | | - Avner Schlessinger
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Katrine M Johannesen
- Department of Regional Health Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Rikke S Møller
- Department of Regional Health Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark; Department of Epilepsy Genetics and Personalized Medicine, Member of ERN Epicare, Danish Epilepsy Centre, Dianalund, Denmark
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | | | - Stephan J Sanders
- Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford OX3 7TY, UK.
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16
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Quinn S, Zhang N, Fenton TA, Brusel M, Muruganandam P, Peleg Y, Giladi M, Haitin Y, Lerche H, Bassan H, Liu Y, Ben-Shalom R, Rubinstein M. Complex biophysical changes and reduced neuronal firing in an SCN8A variant associated with developmental delay and epilepsy. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167127. [PMID: 38519006 DOI: 10.1016/j.bbadis.2024.167127] [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: 12/17/2023] [Revised: 03/07/2024] [Accepted: 03/12/2024] [Indexed: 03/24/2024]
Abstract
Mutations in the SCN8A gene, encoding the voltage-gated sodium channel NaV1.6, are associated with a range of neurodevelopmental syndromes. The p.(Gly1625Arg) (G1625R) mutation was identified in a patient diagnosed with developmental epileptic encephalopathy (DEE). While most of the characterized DEE-associated SCN8A mutations were shown to cause a gain-of-channel function, we show that the G1625R variant, positioned within the S4 segment of domain IV, results in complex effects. Voltage-clamp analyses of NaV1.6G1625R demonstrated a mixture of gain- and loss-of-function properties, including reduced current amplitudes, increased time constant of fast voltage-dependent inactivation, a depolarizing shift in the voltage dependence of activation and inactivation, and increased channel availability with high-frequency repeated depolarization. Current-clamp analyses in transfected cultured neurons revealed that these biophysical properties caused a marked reduction in the number of action potentials when firing was driven by the transfected mutant NaV1.6. Accordingly, computational modeling of mature cortical neurons demonstrated a mild decrease in neuronal firing when mimicking the patients' heterozygous SCN8A expression. Structural modeling of NaV1.6G1625R suggested the formation of a cation-π interaction between R1625 and F1588 within domain IV. Double-mutant cycle analysis revealed that this interaction affects the voltage dependence of inactivation in NaV1.6G1625R. Together, our studies demonstrate that the G1625R variant leads to a complex combination of gain and loss of function biophysical changes that result in an overall mild reduction in neuronal firing, related to the perturbed interaction network within the voltage sensor domain, necessitating personalized multi-tiered analysis for SCN8A mutations for optimal treatment selection.
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Affiliation(s)
- Shir Quinn
- Goldschleger Eye Research Institute, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Nan Zhang
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
| | - Timothy A Fenton
- Neurology Department, MIND Institute, University of California, Davis, Sacramento, CA, United States
| | - Marina Brusel
- Goldschleger Eye Research Institute, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Preethi Muruganandam
- Neurology Department, MIND Institute, University of California, Davis, Sacramento, CA, United States
| | - Yoav Peleg
- Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Moshe Giladi
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Yoni Haitin
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
| | - Haim Bassan
- Pediatric Neurology and Development Center, Shamir Medical Center (Assaf Harofeh), Zerifin, Israel; Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yuanyuan Liu
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany.
| | - Roy Ben-Shalom
- Neurology Department, MIND Institute, University of California, Davis, Sacramento, CA, United States.
| | - Moran Rubinstein
- Goldschleger Eye Research Institute, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
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17
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Bae HG, Wu WC, Nip K, Gould E, Kim JH. Scn2a deletion disrupts oligodendroglia function: Implication for myelination, neural circuitry, and auditory hypersensitivity in ASD. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.15.589242. [PMID: 38659965 PMCID: PMC11042360 DOI: 10.1101/2024.04.15.589242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Autism spectrum disorder (ASD) is characterized by a complex etiology, with genetic determinants significantly influencing its manifestation. Among these, the Scn2a gene emerges as a pivotal player, crucially involved in both glial and neuronal functionality. This study elucidates the underexplored roles of Scn2a in oligodendrocytes, and its subsequent impact on myelination and auditory neural processes. The results reveal a nuanced interplay between oligodendrocytes and axons, where Scn2a deletion causes alterations in the intricate process of myelination. This disruption, in turn, instigates changes in axonal properties and neuronal activities at the single cell level. Furthermore, oligodendrocyte-specific Scn2a deletion compromises the integrity of neural circuitry within auditory pathways, leading to auditory hypersensitivity-a common sensory abnormality observed in ASD. Through transcriptional profiling, we identified alterations in the expression of myelin-associated genes, highlighting the cellular consequences engendered by Scn2a deletion. In summary, the findings provide unprecedented insights into the pathway from Scn2a deletion in oligodendrocytes to sensory abnormalities in ASD, underscoring the integral role of Scn2a -mediated myelination in auditory responses. This research thereby provides novel insights into the intricate tapestry of genetic and cellular interactions inherent in ASD.
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18
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Eltokhi A, Lundstrom BN, Li J, Zweifel LS, Catterall WA, Gamal El-Din TM. Pathogenic gating pore current conducted by autism-related mutations in the Na V1.2 brain sodium channel. Proc Natl Acad Sci U S A 2024; 121:e2317769121. [PMID: 38564633 PMCID: PMC11009634 DOI: 10.1073/pnas.2317769121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 02/26/2024] [Indexed: 04/04/2024] Open
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by social and communication deficits and repetitive behaviors. The genetic heterogeneity of ASD presents a challenge to the development of an effective treatment targeting the underlying molecular defects. ASD gating charge mutations in the KCNQ/KV7 potassium channel cause gating pore currents (Igp) and impair action potential (AP) firing of dopaminergic neurons in brain slices. Here, we investigated ASD gating charge mutations of the voltage-gated SCN2A/NaV1.2 brain sodium channel, which ranked high among the ion channel genes with mutations in individuals with ASD. Our results show that ASD mutations in the gating charges R2 in Domain-II (R853Q), and R1 (R1626Q) and R2 (R1629H) in Domain-IV of NaV1.2 caused Igp in the resting state of ~0.1% of the amplitude of central pore current. The R1626Q mutant also caused significant changes in the voltage dependence of fast inactivation, and the R1629H mutant conducted proton-selective Igp. These potentially pathogenic Igp were exacerbated by the absence of the extracellular Mg2+ and Ca2+. In silico simulation of the effects of these mutations in a conductance-based single-compartment cortical neuron model suggests that the inward Igp reduces the time to peak for the first AP in a train, increases AP rates during a train of stimuli, and reduces the interstimulus interval between consecutive APs, consistent with increased neural excitability and altered input/output relationships. Understanding this common pathophysiological mechanism among different voltage-gated ion channels at the circuit level will give insights into the underlying mechanisms of ASD.
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Affiliation(s)
- Ahmed Eltokhi
- Department of Pharmacology, University of Washington, Seattle, WA98195
| | - Brian Nils Lundstrom
- Department of Neurology in the Division of Epilepsy, Mayo Clinic, Rochester, MN55905
| | - Jin Li
- Department of Pharmacology, University of Washington, Seattle, WA98195
| | - Larry S. Zweifel
- Department of Pharmacology, University of Washington, Seattle, WA98195
- Department of Psychiatry & Behavioral Sciences, University of Washington, Seattle, WA98195
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19
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Nelson AD, Catalfio AM, Gupta JP, Min L, Caballero-Florán RN, Dean KP, Elvira CC, Derderian KD, Kyoung H, Sahagun A, Sanders SJ, Bender KJ, Jenkins PM. Physical and functional convergence of the autism risk genes Scn2a and Ank2 in neocortical pyramidal cell dendrites. Neuron 2024; 112:1133-1149.e6. [PMID: 38290518 PMCID: PMC11097922 DOI: 10.1016/j.neuron.2024.01.003] [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: 06/08/2022] [Revised: 04/26/2023] [Accepted: 01/03/2024] [Indexed: 02/01/2024]
Abstract
Dysfunction in sodium channels and their ankyrin scaffolding partners have both been implicated in neurodevelopmental disorders, including autism spectrum disorder (ASD). In particular, the genes SCN2A, which encodes the sodium channel NaV1.2, and ANK2, which encodes ankyrin-B, have strong ASD association. Recent studies indicate that ASD-associated haploinsufficiency in Scn2a impairs dendritic excitability and synaptic function in neocortical pyramidal cells, but how NaV1.2 is anchored within dendritic regions is unknown. Here, we show that ankyrin-B is essential for scaffolding NaV1.2 to the dendritic membrane of mouse neocortical neurons and that haploinsufficiency of Ank2 phenocopies intrinsic dendritic excitability and synaptic deficits observed in Scn2a+/- conditions. These results establish a direct, convergent link between two major ASD risk genes and reinforce an emerging framework suggesting that neocortical pyramidal cell dendritic dysfunction can contribute to neurodevelopmental disorder pathophysiology.
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Affiliation(s)
- Andrew D Nelson
- Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA, USA
| | - Amanda M Catalfio
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Julie P Gupta
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Lia Min
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Kendall P Dean
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carina C Elvira
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kimberly D Derderian
- Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA, USA
| | - Henry Kyoung
- Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA, USA
| | - Atehsa Sahagun
- Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA, USA
| | - Stephan J Sanders
- Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Psychiatry, University of California, San Francisco, San Francisco, CA, USA
| | - Kevin J Bender
- Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA, USA.
| | - Paul M Jenkins
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA; Department of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, USA.
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20
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Goodchild SJ, Shuart NG, Williams AD, Ye W, Parrish RR, Soriano M, Thouta S, Mezeyova J, Waldbrook M, Dean R, Focken T, Ghovanloo MR, Ruben PC, Scott F, Cohen CJ, Empfield J, Johnson JP. Molecular Pharmacology of Selective Na V1.6 and Dual Na V1.6/Na V1.2 Channel Inhibitors that Suppress Excitatory Neuronal Activity Ex Vivo. ACS Chem Neurosci 2024; 15:1169-1184. [PMID: 38359277 PMCID: PMC10958515 DOI: 10.1021/acschemneuro.3c00757] [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: 11/21/2023] [Revised: 01/25/2024] [Accepted: 01/30/2024] [Indexed: 02/17/2024] Open
Abstract
Voltage-gated sodium channel (NaV) inhibitors are used to treat neurological disorders of hyperexcitability such as epilepsy. These drugs act by attenuating neuronal action potential firing to reduce excitability in the brain. However, all currently available NaV-targeting antiseizure medications nonselectively inhibit the brain channels NaV1.1, NaV1.2, and NaV1.6, which potentially limits the efficacy and therapeutic safety margins of these drugs. Here, we report on XPC-7724 and XPC-5462, which represent a new class of small molecule NaV-targeting compounds. These compounds specifically target inhibition of the NaV1.6 and NaV1.2 channels, which are abundantly expressed in excitatory pyramidal neurons. They have a > 100-fold molecular selectivity against NaV1.1 channels, which are predominantly expressed in inhibitory neurons. Sparing NaV1.1 preserves the inhibitory activity in the brain. These compounds bind to and stabilize the inactivated state of the channels thereby reducing the activity of excitatory neurons. They have higher potency, with longer residency times and slower off-rates, than the clinically used antiseizure medications carbamazepine and phenytoin. The neuronal selectivity of these compounds is demonstrated in brain slices by inhibition of firing in cortical excitatory pyramidal neurons, without impacting fast spiking inhibitory interneurons. XPC-5462 also suppresses epileptiform activity in an ex vivo brain slice seizure model, whereas XPC-7224 does not, suggesting a possible requirement of Nav1.2 inhibition in 0-Mg2+- or 4-AP-induced brain slice seizure models. The profiles of these compounds will facilitate pharmacological dissection of the physiological roles of NaV1.2 and NaV1.6 in neurons and help define the role of specific channels in disease states. This unique selectivity profile provides a new approach to potentially treat disorders of neuronal hyperexcitability by selectively downregulating excitatory circuits.
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Affiliation(s)
- Samuel J. Goodchild
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Noah Gregory Shuart
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Aaron D. Williams
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Wenlei Ye
- Neurocrine
Biosciences, San Diego, California 92130, United States
| | - R. Ryley Parrish
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Maegan Soriano
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Samrat Thouta
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Janette Mezeyova
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Matthew Waldbrook
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Richard Dean
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Thilo Focken
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - Mohammad-Reza Ghovanloo
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
- Department
of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- Department
of Neurology, Yale University, New Haven, Connecticut 06519, United States
| | - Peter C. Ruben
- Department
of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Fiona Scott
- Neurocrine
Biosciences, San Diego, California 92130, United States
| | - Charles J. Cohen
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - James Empfield
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
| | - JP Johnson
- Department
of Cellular and Molecular Biology, Xenon
Pharmaceuticals, Burnaby, BC V5G 4W8, Canada
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21
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Chen GT, Nair G, Osorio AJ, Holley SM, Ghassemzadeh K, Gonzalez J, Lu C, Sanjana NE, Cepeda C, Geschwind DH. Enhancer-targeted CRISPR-Activation Rescues Haploinsufficient Autism Susceptibility Genes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.13.584921. [PMID: 38559217 PMCID: PMC10980046 DOI: 10.1101/2024.03.13.584921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Autism Spectrum Disorder (ASD) is a highly heritable condition with diverse clinical presentations. Approximately 20% of ASD's genetic susceptibility is imparted by de novo mutations of major effect, most of which cause haploinsufficiency. We mapped enhancers of two high confidence autism genes - CHD8 and SCN2A and used CRISPR-based gene activation (CRISPR-A) in hPSC-derived excitatory neurons and cerebral forebrain organoids to correct the effects of haploinsufficiency, taking advantage of the presence of a wildtype allele of each gene and endogenous gene regulation. We found that CRISPR-A induced a sustained increase in CHD8 and SCN2A expression in treated neurons and organoids, with rescue of gene expression levels and mutation-associated phenotypes, including gene expression and physiology. These data support gene activation via targeting enhancers of haploinsufficient genes, as a therapeutic intervention in ASD and other neurodevelopmental disorders.
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22
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Barlow BSM, Longtin A, Joós B. Impact on backpropagation of the spatial heterogeneity of sodium channel kinetics in the axon initial segment. PLoS Comput Biol 2024; 20:e1011846. [PMID: 38489374 PMCID: PMC10942053 DOI: 10.1371/journal.pcbi.1011846] [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: 09/25/2023] [Accepted: 01/21/2024] [Indexed: 03/17/2024] Open
Abstract
In a variety of neurons, action potentials (APs) initiate at the proximal axon, within a region called the axon initial segment (AIS), which has a high density of voltage-gated sodium channels (NaVs) on its membrane. In pyramidal neurons, the proximal AIS has been reported to exhibit a higher proportion of NaVs with gating properties that are "right-shifted" to more depolarized voltages, compared to the distal AIS. Further, recent experiments have revealed that as neurons develop, the spatial distribution of NaV subtypes along the AIS can change substantially, suggesting that neurons tune their excitability by modifying said distribution. When neurons are stimulated axonally, computational modelling has shown that this spatial separation of gating properties in the AIS enhances the backpropagation of APs into the dendrites. In contrast, in the more natural scenario of somatic stimulation, our simulations show that the same distribution can impede backpropagation, suggesting that the choice of orthodromic versus antidromic stimulation can bias or even invert experimental findings regarding the role of NaV subtypes in the AIS. We implemented a range of hypothetical NaV distributions in the AIS of three multicompartmental pyramidal cell models and investigated the precise kinetic mechanisms underlying such effects, as the spatial distribution of NaV subtypes is varied. With axonal stimulation, proximal NaV availability dominates, such that concentrating right-shifted NaVs in the proximal AIS promotes backpropagation. However, with somatic stimulation, the models are insensitive to availability kinetics. Instead, the higher activation threshold of right-shifted NaVs in the AIS impedes backpropagation. Therefore, recently observed developmental changes to the spatial separation and relative proportions of NaV1.2 and NaV1.6 in the AIS differentially impact activation and availability. The observed effects on backpropagation, and potentially learning via its putative role in synaptic plasticity (e.g. through spike-timing-dependent plasticity), are opposite for orthodromic versus antidromic stimulation, which should inform hypotheses about the impact of the developmentally regulated subcellular localization of these NaV subtypes.
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Affiliation(s)
- Benjamin S. M. Barlow
- Department of Physics, University of Ottawa, STEM Complex, 150 Louis-Pasteur Pvt, Ottawa, Ontario, Canada
| | - André Longtin
- Department of Physics, University of Ottawa, STEM Complex, 150 Louis-Pasteur Pvt, Ottawa, Ontario, Canada
- Center for Neural Dynamics and AI, University of Ottawa, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Béla Joós
- Department of Physics, University of Ottawa, STEM Complex, 150 Louis-Pasteur Pvt, Ottawa, Ontario, Canada
- Center for Neural Dynamics and AI, University of Ottawa, Ottawa, Ontario, Canada
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23
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Clatot J, Goldberg EM. No Pain, No Gain of Function: Epilepsy-Associated Variants in SCN2A Defy Classification. Epilepsy Curr 2024; 24:126-128. [PMID: 39280051 PMCID: PMC11394415 DOI: 10.1177/15357597231225565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/18/2024] Open
Abstract
[Box: see text]
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Affiliation(s)
- Jérôme Clatot
- Division of Neurology, Department of Pediatrics, The Children's Hospital of Philadelphia Epilepsy NeuroGenetics Initiative, The Children's Hospital of Philadelphia
| | - Ethan M Goldberg
- Division of Neurology, Department of Pediatrics, The Children's Hospital of Philadelphia Epilepsy NeuroGenetics Initiative, The Children's Hospital of Philadelphia Department of Neurology, The Perelman School of Medicine at The University of Pennsylvania Department of Neuroscience, The Perelman School of Medicine at The University of Pennsylvania
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24
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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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25
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Brown CO, Uy JA, Murtaza N, Rosa E, Alfonso A, Dave BM, Kilpatrick S, Cheng AA, White SH, Scherer SW, Singh KK. Disruption of the autism-associated gene SCN2A alters synaptic development and neuronal signaling in patient iPSC-glutamatergic neurons. Front Cell Neurosci 2024; 17:1239069. [PMID: 38293651 PMCID: PMC10824931 DOI: 10.3389/fncel.2023.1239069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 12/14/2023] [Indexed: 02/01/2024] Open
Abstract
SCN2A is an autism spectrum disorder (ASD) risk gene and encodes a voltage-gated sodium channel. However, the impact of ASD-associated SCN2A de novo variants on human neuron development is unknown. We studied SCN2A using isogenic SCN2A-/- induced pluripotent stem cells (iPSCs), and patient-derived iPSCs harboring a de novo R607* truncating variant. We used Neurogenin2 to generate excitatory (glutamatergic) neurons and found that SCN2A+/R607* and SCN2A-/- neurons displayed a reduction in synapse formation and excitatory synaptic activity. We found differential impact on actional potential dynamics and neuronal excitability that reveals a loss-of-function effect of the R607* variant. Our study reveals that a de novo truncating SCN2A variant impairs the development of human neuronal function.
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Affiliation(s)
- Chad O. Brown
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Jarryll A. Uy
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Nadeem Murtaza
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Elyse Rosa
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Alexandria Alfonso
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Biren M. Dave
- Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- SickKids Research Institute, The Hospital for Sick Children, Toronto, ON, Canada
| | - Savannah Kilpatrick
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Annie A. Cheng
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Sean H. White
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Stephen W. Scherer
- Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- SickKids Research Institute, The Hospital for Sick Children, Toronto, ON, Canada
| | - Karun K. Singh
- Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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26
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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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27
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Echevarria-Cooper DM, Kearney JA. Evaluating the interplay between estrous cyclicity and flurothyl-induced seizure susceptibility in Scn2a K1422E mice. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000850. [PMID: 38162411 PMCID: PMC10757737 DOI: 10.17912/micropub.biology.000850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 10/30/2023] [Accepted: 12/12/2023] [Indexed: 01/03/2024]
Abstract
Recently, we demonstrated that Scn2a K1422E female mice showed a distinct distribution of flurothyl-induced seizure thresholds. To evaluate whether the estrous cycle contributes to this effect, estrous cycle monitoring was performed in mice that had undergone ovariectomy, sham surgery, or no treatment prior to seizure induction. Ovariectomy did not affect the non-unimodal distribution of flurothyl seizure thresholds observed in Scn2a K1422E females. Additionally, seizure thresholds were not associated with estrous cycle stage in mice that underwent sham surgery or in non-surgerized (intact) mice. Interestingly, intact Scn2a K1422E females showed evidence of disrupted estrous cyclicity, an effect not previously described in a genetic epilepsy model.
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28
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Schamiloglu S, Wu H, Zhou M, Kwan AC, Bender KJ. Dynamic Foraging Behavior Performance Is Not Affected by Scn2a Haploinsufficiency. eNeuro 2023; 10:ENEURO.0367-23.2023. [PMID: 38151324 PMCID: PMC10755640 DOI: 10.1523/eneuro.0367-23.2023] [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: 09/19/2023] [Revised: 10/23/2023] [Accepted: 11/14/2023] [Indexed: 12/29/2023] Open
Abstract
Dysfunction in the gene SCN2A, which encodes the voltage-gated sodium channel Nav1.2, is strongly associated with neurodevelopmental disorders including autism spectrum disorder and intellectual disability (ASD/ID). This dysfunction typically manifests in these disorders as a haploinsufficiency, where loss of one copy of a gene cannot be compensated for by the other allele. Scn2a haploinsufficiency affects a range of cells and circuits across the brain, including associative neocortical circuits that are important for cognitive flexibility and decision-making behaviors. Here, we tested whether Scn2a haploinsufficiency has any effect on a dynamic foraging task that engages such circuits. Scn2a +/- mice and wild-type (WT) littermates were trained on a choice behavior where the probability of reward between two options varied dynamically across trials and where the location of the high reward underwent uncued reversals. Despite impairments in Scn2a-related neuronal excitability, we found that both male and female Scn2a +/- mice performed these tasks as well as wild-type littermates, with no behavioral difference across genotypes in learning or performance parameters. Varying the number of trials between reversals or probabilities of receiving reward did not result in an observable behavioral difference, either. These data suggest that, despite heterozygous loss of Scn2a, mice can perform relatively complex foraging tasks that make use of higher-order neuronal circuits.
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Affiliation(s)
- Selin Schamiloglu
- Neuroscience Graduate Program, University of California, San Francisco, CA 94158
- Center for Integrative Neuroscience, Department of Neurology, University of California, San Francisco, CA 94158
| | - Hao Wu
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06511
| | - Mingkang Zhou
- Neuroscience Graduate Program, University of California, San Francisco, CA 94158
- Center for Integrative Neuroscience, Department of Neurology, University of California, San Francisco, CA 94158
| | - Alex C Kwan
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06511
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
| | - Kevin J Bender
- Center for Integrative Neuroscience, Department of Neurology, University of California, San Francisco, CA 94158
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29
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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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30
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Thompson CH, Potet F, Abramova TV, DeKeyser JM, Ghabra NF, Vanoye CG, Millichap JJ, George AL. Epilepsy-associated SCN2A (NaV1.2) variants exhibit diverse and complex functional properties. J Gen Physiol 2023; 155:e202313375. [PMID: 37578743 PMCID: PMC10424433 DOI: 10.1085/jgp.202313375] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 06/29/2023] [Accepted: 07/25/2023] [Indexed: 08/15/2023] Open
Abstract
Pathogenic variants in voltage-gated sodium (NaV) channel genes including SCN2A, encoding NaV1.2, are discovered frequently in neurodevelopmental disorders with or without epilepsy. SCN2A is also a high-confidence risk gene for autism spectrum disorder (ASD) and nonsyndromic intellectual disability (ID). Previous work to determine the functional consequences of SCN2A variants yielded a paradigm in which predominantly gain-of-function variants cause neonatal-onset epilepsy, whereas loss-of-function variants are associated with ASD and ID. However, this framework was derived from a limited number of studies conducted under heterogeneous experimental conditions, whereas most disease-associated SCN2A variants have not been functionally annotated. We determined the functional properties of SCN2A variants using automated patch-clamp recording to demonstrate the validity of this method and to examine whether a binary classification of variant dysfunction is evident in a larger cohort studied under uniform conditions. We studied 28 disease-associated variants and 4 common variants using two alternatively spliced isoforms of NaV1.2 expressed in HEK293T cells. Automated patch-clamp recording provided a valid high throughput method to ascertain detailed functional properties of NaV1.2 variants with concordant findings for variants that were previously studied using manual patch clamp. Many epilepsy-associated variants in our study exhibited complex patterns of gain- and loss-of-functions that are difficult to classify by a simple binary scheme. The higher throughput achievable with automated patch clamp enables study of variants with greater standardization of recording conditions, freedom from operator bias, and enhanced experimental rigor. This approach offers an enhanced ability to discern relationships between channel dysfunction and neurodevelopmental disorders.
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Affiliation(s)
- Christopher H. Thompson
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Franck Potet
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Tatiana V. Abramova
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Jean-Marc DeKeyser
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Nora F. Ghabra
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Carlos G. Vanoye
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - John J. Millichap
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Alfred L. George
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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31
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Yang Y, Wu J, Zhang J, Chen X, Que Z, Wettschurack K, Deming B, Acosta M, Cui N, Eaton M, Zhao Y, Halurkar M, Purba M, Chen I, Xiao T, Suzuki M, Yuan C, Xu R, Koss W, Du D, Chen F, Wu LJ, Clinic M. Microglial over-pruning of synapses during development in autism-associated SCN2A-deficient mice and human cerebral organoids. RESEARCH SQUARE 2023:rs.3.rs-3270664. [PMID: 37841865 PMCID: PMC10571631 DOI: 10.21203/rs.3.rs-3270664/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
Autism spectrum disorder (ASD) is a major neurodevelopmental disorder affecting 1 in 36 children in the United States. While neurons have been the focus to understand ASD, an altered neuro-immune response in the brain may be closely associated with ASD, and a neuro-immune interaction could play a role in the disease progression. As the resident immune cells of the brain, microglia regulate brain development and homeostasis via core functions including phagocytosis of synapses. While ASD has been traditionally considered a polygenic disorder, recent large-scale human genetic studies have identified SCN2A deficiency as a leading monogenic cause of ASD and intellectual disability. We generated a Scn2a-deficient mouse model, which displays major behavioral and neuronal phenotypes. However, the role of microglia in this disease model is unknown. Here, we reported that Scn2a-deficient mice have impaired learning and memory, accompanied by reduced synaptic transmission and lower spine density in neurons of the hippocampus. Microglia in Scn2a-deficient mice are partially activated, exerting excessive phagocytic pruning of post-synapses related to the complement C3 cascades during selective developmental stages. The ablation of microglia using PLX3397 partially restores synaptic transmission and spine density. To extend our findings from rodents to human cells, we established a microglial-incorporated human cerebral organoid model carrying an SCN2A protein-truncating mutation identified in children with ASD. We found that human microglia display increased elimination of post-synapse in cerebral organoids carrying the SCN2A mutation. Our study establishes a key role of microglia in multi-species autism-associated models of SCN2A deficiency from mouse to human cells.
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Affiliation(s)
- Yang Yang
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Jiaxiang Wu
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Jingliang Zhang
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Xiaoling Chen
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Zhefu Que
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Kyle Wettschurack
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Brody Deming
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Maria Acosta
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Ningren Cui
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Muriel Eaton
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Yuanrui Zhao
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Manasi Halurkar
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Mandal Purba
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
| | - Ian Chen
- Purdue University College of Pharmacy & Purdue Institute for Integrative Neuroscience (PIIN)
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32
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Fréal A, Jamann N, Ten Bos J, Jansen J, Petersen N, Ligthart T, Hoogenraad CC, Kole MH. Sodium channel endocytosis drives axon initial segment plasticity. SCIENCE ADVANCES 2023; 9:eadf3885. [PMID: 37713493 PMCID: PMC10881073 DOI: 10.1126/sciadv.adf3885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 08/15/2023] [Indexed: 09/17/2023]
Abstract
Activity-dependent plasticity of the axon initial segment (AIS) endows neurons with the ability to adapt action potential output to changes in network activity. Action potential initiation at the AIS highly depends on the clustering of voltage-gated sodium channels, but the molecular mechanisms regulating their plasticity remain largely unknown. Here, we developed genetic tools to label endogenous sodium channels and their scaffolding protein, to reveal their nanoscale organization and longitudinally image AIS plasticity in hippocampal neurons in slices and primary cultures. We find that N-methyl-d-aspartate receptor activation causes both long-term synaptic depression and rapid internalization of AIS sodium channels within minutes. The clathrin-mediated endocytosis of sodium channels at the distal AIS increases the threshold for action potential generation. These data reveal a fundamental mechanism for rapid activity-dependent AIS reorganization and suggests that plasticity of intrinsic excitability shares conserved features with synaptic plasticity.
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Affiliation(s)
- Amélie Fréal
- Axonal Signaling Group, Netherlands Institute for Neurosciences (NIN), Royal Netherlands Academy for Arts and Sciences (KNAW), Amsterdam, Netherlands
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Nora Jamann
- Axonal Signaling Group, Netherlands Institute for Neurosciences (NIN), Royal Netherlands Academy for Arts and Sciences (KNAW), Amsterdam, Netherlands
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Jolijn Ten Bos
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Jacqueline Jansen
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Naomi Petersen
- Axonal Signaling Group, Netherlands Institute for Neurosciences (NIN), Royal Netherlands Academy for Arts and Sciences (KNAW), Amsterdam, Netherlands
| | - Thijmen Ligthart
- Axonal Signaling Group, Netherlands Institute for Neurosciences (NIN), Royal Netherlands Academy for Arts and Sciences (KNAW), Amsterdam, Netherlands
| | - Casper C. Hoogenraad
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
- Department of Neuroscience, Genentech Inc, South San Francisco, CA, USA
| | - Maarten H. P. Kole
- Axonal Signaling Group, Netherlands Institute for Neurosciences (NIN), Royal Netherlands Academy for Arts and Sciences (KNAW), Amsterdam, Netherlands
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
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33
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Sznajder L, Khan M, Tadross M, Ciesiołka A, Nutter C, Taylor K, Pearson C, Sobczak K, Lewis M, Swanson M, Yuen R. Autistic traits in myotonic dystrophy type 1 due to MBNL inhibition and RNA mis-splicing. RESEARCH SQUARE 2023:rs.3.rs-3221704. [PMID: 37645891 PMCID: PMC10462192 DOI: 10.21203/rs.3.rs-3221704/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Tandem repeat expansions are enriched in autism spectrum disorder, including CTG expansion in the DMPK gene that underlines myotonic muscular dystrophy type 1. Although the clinical connection of autism to myotonic dystrophy is corroborated, the molecular links remained unknown. Here, we show a mechanistic path of autism via repeat expansion in myotonic dystrophy. We found that inhibition of muscleblind-like (MBNL) splicing factors by expanded CUG RNAs alerts the splicing of autism-risk genes during brain development especially a class of autism-relevant microexons. To provide in vivo evidence that the CTG expansion and MBNL inhibition axis leads to the presentation of autistic traits, we demonstrate that CTG expansion and MBNL-null mouse models recapitulate autism-relevant mis-splicing profiles and demonstrate social deficits. Our findings indicate that DMPK CTG expansion-associated autism arises from developmental mis-splicing. Understanding this pathomechanistic connection provides an opportunity for greater in-depth investigations of mechanistic threads in autism.
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34
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Pablo JLB, Cornett SL, Wang LA, Jo S, Brünger T, Budnik N, Hegde M, DeKeyser JM, Thompson CH, Doench JG, Lal D, George AL, Pan JQ. Scanning mutagenesis of the voltage-gated sodium channel Na V1.2 using base editing. Cell Rep 2023; 42:112563. [PMID: 37267104 PMCID: PMC10592450 DOI: 10.1016/j.celrep.2023.112563] [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: 08/09/2022] [Revised: 03/24/2023] [Accepted: 05/08/2023] [Indexed: 06/04/2023] Open
Abstract
It is challenging to apply traditional mutational scanning to voltage-gated sodium channels (NaVs) and functionally annotate the large number of coding variants in these genes. Using a cytosine base editor and a pooled viability assay, we screen a library of 368 guide RNAs (gRNAs) tiling NaV1.2 to identify more than 100 gRNAs that change NaV1.2 function. We sequence base edits made by a subset of these gRNAs to confirm specific variants that drive changes in channel function. Electrophysiological characterization of these channel variants validates the screen results and provides functional mechanisms of channel perturbation. Most of the changes caused by these gRNAs are classifiable as loss of function along with two missense mutations that lead to gain of function in NaV1.2 channels. This two-tiered strategy to functionally characterize ion channel protein variants at scale identifies a large set of loss-of-function mutations in NaV1.2.
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Affiliation(s)
- Juan Lorenzo B Pablo
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Savannah L Cornett
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Lei A Wang
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Sooyeon Jo
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Tobias Brünger
- Cologne Center for Genomics, University of Cologne, 51149 Cologne, Germany; Genomic Medicine Institute, Lerner Research Institute, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Nikita Budnik
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Mudra Hegde
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jean-Marc DeKeyser
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Christopher H Thompson
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - John G Doench
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Dennis Lal
- Cologne Center for Genomics, University of Cologne, 51149 Cologne, Germany; Genomic Medicine Institute, Lerner Research Institute, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA; Department of Neurology, McGovern Medical School, UTHealth, Houston, TX 77030, USA
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Jen Q Pan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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35
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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: 6] [Impact Index Per Article: 6.0] [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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Stott J, Wright T, Holmes J, Wilson J, Griffiths-Jones S, Foster D, Wright B. A systematic review of non-coding RNA genes with differential expression profiles associated with autism spectrum disorders. PLoS One 2023; 18:e0287131. [PMID: 37319303 PMCID: PMC10270643 DOI: 10.1371/journal.pone.0287131] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 05/30/2023] [Indexed: 06/17/2023] Open
Abstract
AIMS To identify differential expression of shorter non-coding RNA (ncRNA) genes associated with autism spectrum disorders (ASD). BACKGROUND ncRNA are functional molecules that derive from non-translated DNA sequence. The HUGO Gene Nomenclature Committee (HGNC) have approved ncRNA gene classes with alignment to the reference human genome. One subset is microRNA (miRNA), which are highly conserved, short RNA molecules that regulate gene expression by direct post-transcriptional repression of messenger RNA. Several miRNA genes are implicated in the development and regulation of the nervous system. Expression of miRNA genes in ASD cohorts have been examined by multiple research groups. Other shorter classes of ncRNA have been examined less. A comprehensive systematic review examining expression of shorter ncRNA gene classes in ASD is timely to inform the direction of research. METHODS We extracted data from studies examining ncRNA gene expression in ASD compared with non-ASD controls. We included studies on miRNA, piwi-interacting RNA (piRNA), small NF90 (ILF3) associated RNA (snaR), small nuclear RNA (snRNA), small nucleolar RNA (snoRNA), transfer RNA (tRNA), vault RNA (vtRNA) and Y RNA. The following electronic databases were searched: Cochrane Library, EMBASE, PubMed, Web of Science, PsycINFO, ERIC, AMED and CINAHL for papers published from January 2000 to May 2022. Studies were screened by two independent investigators with a third resolving discrepancies. Data was extracted from eligible papers. RESULTS Forty-eight eligible studies were included in our systematic review with the majority examining miRNA gene expression alone. Sixty-four miRNA genes had differential expression in ASD compared to controls as reported in two or more studies, but often in opposing directions. Four miRNA genes had differential expression in the same direction in the same tissue type in at least 3 separate studies. Increased expression was reported in miR-106b-5p, miR-155-5p and miR-146a-5p in blood, post-mortem brain, and across several tissue types, respectively. Decreased expression was reported in miR-328-3p in bloods samples. Seven studies examined differential expression from other classes of ncRNA, including piRNA, snRNA, snoRNA and Y RNA. No individual ncRNA genes were reported in more than one study. Six studies reported differentially expressed snoRNA genes in ASD. A meta-analysis was not possible because of inconsistent methodologies, disparate tissue types examined, and varying forms of data presented. CONCLUSION There is limited but promising evidence associating the expression of certain miRNA genes and ASD, although the studies are of variable methodological quality and the results are largely inconsistent. There is emerging evidence associating differential expression of snoRNA genes in ASD. It is not currently possible to say whether the reports of differential expression in ncRNA may relate to ASD aetiology, a response to shared environmental factors linked to ASD such as sleep and nutrition, other molecular functions, human diversity, or chance findings. To improve our understanding of any potential association, we recommend improved and standardised methodologies and reporting of raw data. Further high-quality research is required to shine a light on possible associations, which may yet yield important information.
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Affiliation(s)
- Jon Stott
- Child Oriented Mental Health Intervention Collaborative (COMIC), University of York in Collaboration with Leeds and York Partnership NHS Foundation Trust, York, United Kingdom
- Tees, Esk & Wear Valleys NHS Foundation Trust, Foss Park Hospital, York, United Kingdom
| | - Thomas Wright
- Manchester Centre for Genomic Medicine, Clinical Genetics Service, Saint Mary’s Hospital, Manchester University NHS Foundation Trust, Manchester, United Kingdom
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Jannah Holmes
- Child Oriented Mental Health Intervention Collaborative (COMIC), University of York in Collaboration with Leeds and York Partnership NHS Foundation Trust, York, United Kingdom
- Hull York Medical School, University of York, Heslington, York, United Kingdom
| | - Julie Wilson
- Department of Mathematics, University of York, Heslington, York, United Kingdom
| | - Sam Griffiths-Jones
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Deborah Foster
- Tees, Esk & Wear Valleys NHS Foundation Trust, Foss Park Hospital, York, United Kingdom
| | - Barry Wright
- Child Oriented Mental Health Intervention Collaborative (COMIC), University of York in Collaboration with Leeds and York Partnership NHS Foundation Trust, York, United Kingdom
- Hull York Medical School, University of York, Heslington, York, United Kingdom
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Echevarria-Cooper DM, Hawkins NA, Kearney JA. Strain-dependent effects on neurobehavioral and seizure phenotypes in Scn2aK1422E mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.06.543929. [PMID: 37333275 PMCID: PMC10274703 DOI: 10.1101/2023.06.06.543929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Pathogenic variants in SCN2A are associated with a range of neurodevelopmental disorders (NDD). Despite being largely monogenic, SCN2A-related NDD show considerable phenotypic variation and complex genotype-phenotype correlations. Genetic modifiers can contribute to variability in disease phenotypes associated with rare driver mutations. Accordingly, different genetic backgrounds across inbred rodent strains have been shown to influence disease-related phenotypes, including those associated with SCN2A-related NDD. Recently, we developed a mouse model of the variant SCN2A-p.K1422E that was maintained as an isogenic line on the C57BL/6J (B6) strain. Our initial characterization of NDD phenotypes in heterozygous Scn2aK1422E mice revealed alterations in anxiety-related behavior and seizure susceptibility. To determine if background strain affects phenotype severity in the Scn2aK1422E mouse model, phenotypes of mice on B6 and [DBA/2J×B6]F1 hybrid (F1D2) strains were compared. Convergent evidence from neurobehavioral assays demonstrated lower anxiety-like behavior in Scn2aK1422E mice compared to wild-type and further suggested that this effect is more pronounced on the B6 background compared to the F1D2 background. Although there were no strain-dependent differences in occurrence of rare spontaneous seizures, response to the chemoconvulsant kainic acid revealed differences in seizure generalization and lethality risk, with variation based on strain and sex. Continued examination of strain-dependent effects in the Scn2aK1422E mouse model could reveal genetic backgrounds with unique susceptibility profiles that would be relevant for future studies on specific traits and enable the identification of highly penetrant phenotypes and modifier genes that could provide clues about the primary pathogenic mechanism of the K1422E variant.
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Affiliation(s)
- Dennis M. Echevarria-Cooper
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Northwestern University Interdepartmental Neuroscience Program, Northwestern University, Chicago, IL 60611, USA
| | - Nicole A. Hawkins
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Jennifer A. Kearney
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Northwestern University Interdepartmental Neuroscience Program, Northwestern University, Chicago, IL 60611, USA
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Dolma S, Joshi A. The Node of Ranvier as an Interface for Axo-Glial Interactions: Perturbation of Axo-Glial Interactions in Various Neurological Disorders. J Neuroimmune Pharmacol 2023; 18:215-234. [PMID: 37285016 DOI: 10.1007/s11481-023-10072-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 05/19/2023] [Indexed: 06/08/2023]
Abstract
The action potential conduction along the axon is highly dependent on the healthy interactions between the axon and myelin-producing glial cells. Myelin, which facilitates action potential, is the protective insulation around the axon formed by Schwann cells and oligodendrocytes in the peripheral (PNS) and central nervous system (CNS), respectively. Myelin is a continuous structure with intermittent gaps called nodes of Ranvier, which are the sites enriched with ion channels, transmembrane, scaffolding, and cytoskeletal proteins. Decades-long extensive research has identified a comprehensive proteome with strictly regularized localization at the node of Ranvier. Concurrently, axon-glia interactions at the node of Ranvier have gathered significant attention as the pathophysiological targets for various neurodegenerative disorders. Numerous studies have shown the alterations in the axon-glia interactions culminating in neurological diseases. In this review, we have provided an update on the molecular composition of the node of Ranvier. Further, we have discussed in detail the consequences of disruption of axon-glia interactions during the pathogenesis of various CNS and PNS disorders.
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Affiliation(s)
- Sonam Dolma
- Department of Pharmacy, Birla Institute of Technology and Sciences- Pilani, Hyderabad campus, Telangana state, India
| | - Abhijeet Joshi
- Department of Pharmacy, Birla Institute of Technology and Sciences- Pilani, Hyderabad campus, Telangana state, India.
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Vien T, Ta M, Kimura L, Onay T, DeCaen P. Primary cilia TRP channel regulates hippocampal excitability. Proc Natl Acad Sci U S A 2023; 120:e2219686120. [PMID: 37216541 PMCID: PMC10235993 DOI: 10.1073/pnas.2219686120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 04/25/2023] [Indexed: 05/24/2023] Open
Abstract
Polycystins (PKD2, PKD2L1, and PKD2L2) are members of the transient receptor potential family, which form ciliary ion channels. Most notably, PKD2 dysregulation in the kidney nephron cilia is associated with polycystic kidney disease, but the function of PKD2L1 in neurons is undefined. In this report, we develop animal models to track the expression and subcellular localization of PKD2L1 in the brain. We discover that PKD2L1 localizes and functions as a Ca2+ channel in the primary cilia of hippocampal neurons that apically radiate from the soma. Loss of PKD2L1 expression ablates primary ciliary maturation and attenuates neuronal high-frequency excitability, which precipitates seizure susceptibility and autism spectrum disorder-like behavior in mice. The disproportionate impairment of interneuron excitability suggests that circuit disinhibition underlies the neurophenotypic features of these mice. Our results identify PKD2L1 channels as regulators of hippocampal excitability and the neuronal primary cilia as organelle mediators of brain electrical signaling.
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Affiliation(s)
- Thuy N. Vien
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - My C. Ta
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Louise F. Kimura
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Tuncer Onay
- Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL60911
| | - Paul G. DeCaen
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
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Echevarria-Cooper DM, Kearney JA. Evaluating the interplay between estrous cyclicity and induced seizure susceptibility in Scn2aK1422E mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.27.538584. [PMID: 37163100 PMCID: PMC10168397 DOI: 10.1101/2023.04.27.538584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Pathogenic variants in SCN2A are associated with a range of neurodevelopmental disorders (NDD). SCN2A-related NDD show wide phenotypic heterogeneity, suggesting that modifying factors must be considered in order to properly elucidate the mechanisms of pathogenic variants. Recently, we characterized neurological phenotypes in a mouse model of the variant SCN2A-p.K1422E. We demonstrated that heterozygous Scn2aK1422E female mice showed a distinct, reproducible distribution of flurothyl-induced seizure thresholds. Women with epilepsy often show a cyclical pattern of altered seizure susceptibility during specific phases of the menstrual cycle which can be attributed to fluctuations in hormones and corresponding changes in neurosteroid levels. Rodent models have been used extensively to examine the relationship between the estrous (menstrual) cycle, steroid hormones, and seizure susceptibility. However, the effects of the estrous cycle on seizure susceptibility have not been evaluated in the context of an epilepsy-associated genetic variant. To determine whether the estrous cycle affects susceptibility to flurothyl-induced seizures in Scn2aK1422E female mice, estrous cycle monitoring was performed in mice that had undergone ovariectomy (OVX), sham surgery, or no treatment prior to seizure induction. Removing the influence of circulating sex hormones via OVX did not affect the non-unimodal distribution of flurothyl seizure thresholds observed in Scn2aK1422E females. Additionally, flurothyl seizure thresholds were not associated with estrous cycle stage in mice that underwent sham surgery or were untreated. These data suggest that variation in Scn2aK1422E flurothyl seizure threshold is not significantly influenced by the estrous cycle and, by extension, fluctuations in ovarian hormones. Interestingly, untreated Scn2aK1422E females showed evidence of disrupted estrous cyclicity, an effect not previously described in a genetic epilepsy model. This unexpected result highlights the importance of considering sex specific effects and the estrous cycle in support of more inclusive biomedical research.
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Affiliation(s)
- Dennis M. Echevarria-Cooper
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Northwestern University Interdepartmental Neuroscience Program, Northwestern University, Chicago, IL 60611, USA
| | - Jennifer A. Kearney
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Northwestern University Interdepartmental Neuroscience Program, Northwestern University, Chicago, IL 60611, USA
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Gupta JP, Jenkins PM. Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel Na V1.2 in neurons. Front Physiol 2023; 14:959660. [PMID: 37064897 PMCID: PMC10098127 DOI: 10.3389/fphys.2023.959660] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 03/21/2023] [Indexed: 04/01/2023] Open
Abstract
Neuronal ankyrin-B is an intracellular scaffolding protein that plays multiple roles in the axon. By contrast, relatively little is known about the function of ankyrin-B in dendrites, where ankyrin-B is also localized in mature neurons. Recently, we showed that ankyrin-B acts as a scaffold for the voltage-gated sodium channel, NaV1.2, in dendrites of neocortical pyramidal neurons. How ankyrin-B is itself targeted to the dendritic membrane is not well understood. Here, we report that ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic localization of NaV1.2. We identify the palmitoyl acyl transferase zDHHC17 as a key mediator of ankyrin-B palmitoylation in heterologous cells and in neurons. Additionally, we find that zDHHC17 regulates ankyrin-B protein levels independently of its S-acylation function through a conserved binding mechanism between the ANK repeat domain of zDHHC17 and the zDHHC ankyrin-repeat binding motif of ankyrin-B. We subsequently identify five cysteines in the N-terminal ankyrin repeat domain of ankyrin-B that are necessary for ankyrin-B palmitoylation. Mutation of these five cysteines to alanines not only abolishes ankyrin-B palmitoylation, but also prevents ankyrin-B from scaffolding NaV1.2 at dendritic membranes of neurons due to ankyrin-B's inability to localize properly at dendrites. Thus, we show palmitoylation is critical for localization and function of ankyrin-B at dendrites. Strikingly, loss of ankyrin-B palmitoylation does not affect ankyrin-B-mediated axonal cargo transport of synaptic vesicle synaptotagmin-1 in neurons. This is the first demonstration of S-palmitoylation of ankyrin-B as an underlying mechanism required for ankyrin-B localization and function in scaffolding NaV1.2 at dendrites.
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Affiliation(s)
- Julie P. Gupta
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Paul M. Jenkins
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, United States
- Department of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, United States
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Thompson CH, Potet F, Abramova TV, DeKeyser JM, Ghabra NF, Vanoye CG, Millichap J, George AL. Epilepsy-associated SCN2A (Na V 1.2) Variants Exhibit Diverse and Complex Functional Properties. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.23.529757. [PMID: 36865317 PMCID: PMC9980081 DOI: 10.1101/2023.02.23.529757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Pathogenic variants in neuronal voltage-gated sodium (Na V ) channel genes including SCN2A , which encodes Na V 1.2, are frequently discovered in neurodevelopmental disorders with and without epilepsy. SCN2A is also a high confidence risk gene for autism spectrum disorder (ASD) and nonsyndromic intellectual disability (ID). Previous work to determine the functional consequences of SCN2A variants yielded a paradigm in which predominantly gain-of-function (GoF) variants cause epilepsy whereas loss-of-function (LoF) variants are associated with ASD and ID. However, this framework is based on a limited number of functional studies conducted under heterogenous experimental conditions whereas most disease-associated SCN2A variants have not been functionally annotated. We determined the functional properties of more than 30 SCN2A variants using automated patch clamp recording to assess the analytical validity of this approach and to examine whether a binary classification of variant dysfunction is evident in a larger cohort studied under uniform conditions. We studied 28 disease-associated variants and 4 common population variants using two distinct alternatively spliced forms of Na V 1.2 that were heterologously expressed in HEK293T cells. Multiple biophysical parameters were assessed on 5,858 individual cells. We found that automated patch clamp recording provided a valid high throughput method to ascertain detailed functional properties of Na V 1.2 variants with concordant findings for a subset of variants that were previously studied using manual patch clamp. Additionally, many epilepsy-associated variants in our study exhibited complex patterns of gain- and loss-of-function properties that are difficult to classify overall by a simple binary scheme. The higher throughput achievable with automated patch clamp enables study of a larger number of variants, greater standardization of recording conditions, freedom from operator bias, and enhanced experimental rigor valuable for accurate assessment of Na V channel variant dysfunction. Together, this approach will enhance our ability to discern relationships between variant channel dysfunction and neurodevelopmental disorders.
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Affiliation(s)
- Christopher H Thompson
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Franck Potet
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Tatiana V Abramova
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Jean-Marc DeKeyser
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Nora F Ghabra
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Carlos G Vanoye
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - John Millichap
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Alfred L George
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
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Ghosh A, Nadella N, Monaghan-Nichols AP, Chu XP. Gene Therapy as an Emerging Treatment for Scn2a Mutation-Induced Autism Spectrum Disorders. FUNDAMENTAL RESEARCH 2023. [DOI: 10.1016/j.fmre.2023.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
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Hu X, Jing M, Wang Y, Liu Y, Hua Y. Functional analysis of a novel de novo SCN2A variant in a patient with seizures refractory to oxcarbazepine. Front Mol Neurosci 2023; 16:1159649. [PMID: 37152433 PMCID: PMC10158977 DOI: 10.3389/fnmol.2023.1159649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 03/29/2023] [Indexed: 05/09/2023] Open
Abstract
Objective We admitted a female patient with infantile onset epilepsy (<3-month-old). The use of oxcarbazepine exacerbated epileptic seizures in the patient. In the present study, we aimed to identify the genetic basis of the infantile onset epilepsy in the patient, and determine the correlations among genotype, phenotype, and clinical drug response. Methods We described the clinical characteristics of an infant with refractory epilepsy. Whole exome sequencing (WES) was used to screen for the pathogenic variant. Whole-cell patch-clamp was performed to determine functional outcomes of the variant. Results WES identified a novel de novo SCN2A variant (c.468 G > C, p.K156N) in the patient. In comparison with wildtype, electrophysiology revealed that SCN2A-K156N variant in transfected cells demonstrated reduced sodium current density, delayed activation and accelerated inactivation process of Na+ channel, all of which suggested a loss-of-function (LOF) of Nav1.2 channel. Conclusion We showed the importance of functional analysis for a SCN2A variant with unknown significance to determine pathogenicity, drug reactions, and genotype-phenotype correlations. For patients suffering from early infantile epilepsies, the use of oxcarbazepine in some SCN2A-related epilepsies requires vigilance to assess the possibility of epilepsy worsening.
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Affiliation(s)
- Xiaoyue Hu
- Department of Neurology, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, China
| | - Miao Jing
- Department of Neurology, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, China
| | - Yanping Wang
- Department of Neurology, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, China
| | - Yanshan Liu
- Department of Pediatric Laboratory, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, China
- *Correspondence: Yanshan Liu,
| | - Ying Hua
- Department of Neurology, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, China
- Ying Hua,
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Structural basis for Na V1.7 inhibition by pore blockers. Nat Struct Mol Biol 2022; 29:1208-1216. [PMID: 36424527 DOI: 10.1038/s41594-022-00860-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 10/11/2022] [Indexed: 11/26/2022]
Abstract
Voltage-gated sodium channel NaV1.7 plays essential roles in pain and odor perception. NaV1.7 variants cause pain disorders. Accordingly, NaV1.7 has elicited extensive attention in developing new analgesics. Here we present cryo-EM structures of human NaV1.7/β1/β2 complexed with inhibitors XEN907, TC-N1752 and NaV1.7-IN2, explaining specific binding sites and modulation mechanism for the pore blockers. These inhibitors bind in the central cavity blocking ion permeation, but engage different parts of the cavity wall. XEN907 directly causes α- to π-helix transition of DIV-S6 helix, which tightens the fast inactivation gate. TC-N1752 induces π-helix transition of DII-S6 helix mediated by a conserved asparagine on DIII-S6, which closes the activation gate. NaV1.7-IN2 serves as a pore blocker without causing conformational change. Electrophysiological results demonstrate that XEN907 and TC-N1752 stabilize NaV1.7 in inactivated state and delay the recovery from inactivation. Our results provide structural framework for NaV1.7 modulation by pore blockers, and important implications for developing subtype-selective analgesics.
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Palmer EE, Sachdev R, Beavis E, Macintosh R, Le Marne FA, Nevin SM, Bye AM, Nunn K. Hope in the uncertainties and certainty for parents of children with rare neurological disorders. Part I (of 3): Uncertainty. J Paediatr Child Health 2022; 58:1718-1721. [PMID: 36069374 DOI: 10.1111/jpc.16165] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 08/01/2022] [Indexed: 12/14/2022]
Abstract
This is the first of three articles exploring the aspects of clinical care for children with rare neurological disorders including uncertainties old and new. The disruptive technologies of genomic sequencing and advanced therapeutics such as gene-based therapies offer parents of children with severe but rare neurological conditions for the first-time unprecedented opportunities for 'precision medicine'. At the same time, the realities of limited genomic diagnostic yields and not infrequent detection of variants of uncertain significance, lack of natural history study data and management guidelines for individually rare neurogenetic conditions, means that high pre-genomic test expectations are all too often replaced by an accumulation of new uncertainties. This can add to the chronic traumatic stress experienced by many families but may also have under-recognised impacts for their clinicians, contributing to 'burn-out' and attendant negative psychosocial impacts. This first article aims to address how clinicians might manage the accumulation of uncertainties to be more helpful to patients and their families. Moreover, it seeks to address how clinicians can move forward providing compassionate care to their patients and a little more consideration for themselves.
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Affiliation(s)
- Elizabeth E Palmer
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Rani Sachdev
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Erin Beavis
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Department of Neurology, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Rebecca Macintosh
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Fleur A Le Marne
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Department of Neurology, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Suzanne M Nevin
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Ann Me Bye
- Discipline of Paediatrics and Child Health, School of Clinical Medicine Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.,Department of Neurology, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia
| | - Kenneth Nunn
- Department of Psychological Medicine, Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Psychological Medicine, University of Sydney, Sydney, New South Wales, Australia
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Thouta S, Waldbrook MG, Lin S, Mahadevan A, Mezeyova J, Soriano M, Versi P, Goodchild SJ, Parrish RR. Pharmacological determination of the fractional block of Nav channels required to impair neuronal excitability and ex vivo seizures. Front Cell Neurosci 2022; 16:964691. [PMID: 36246527 PMCID: PMC9557217 DOI: 10.3389/fncel.2022.964691] [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: 06/09/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
Voltage-gated sodium channels (Nav) are essential for the initiation and propagation of action potentials in neurons. Of the nine human channel subtypes, Nav1.1, Nav1.2 and Nav1.6 are prominently expressed in the adult central nervous system (CNS). All three of these sodium channel subtypes are sensitive to block by the neurotoxin tetrodotoxin (TTX), with TTX being almost equipotent on all three subtypes. In the present study we have used TTX to determine the fractional block of Nav channels required to impair action potential firing in pyramidal neurons and reduce network seizure-like activity. Using automated patch-clamp electrophysiology, we first determined the IC50s of TTX on mouse Nav1.1, Nav1.2 and Nav1.6 channels expressed in HEK cells, demonstrating this to be consistent with previously published data on human orthologs. We then compared this data to the potency of block of Nav current measured in pyramidal neurons from neocortical brain slices. Interestingly, we found that it requires nearly 10-fold greater concentration of TTX over the IC50 to induce significant block of action potentials using a current-step protocol. In contrast, concentrations near the IC50 resulted in a significant reduction in AP firing and increase in rheobase using a ramp protocol. Surprisingly, a 20% reduction in action potential generation observed with 3 nM TTX resulted in significant block of seizure-like activity in the 0 Mg2+ model of epilepsy. Additionally, we found that approximately 50% block in pyramidal cell intrinsic excitability is sufficient to completely block all seizure-like events. Furthermore, we also show that the anticonvulsant drug phenytoin blocked seizure-like events in a manner similar to TTX. These data serve as a critical starting point in understanding how fractional block of Nav channels affect intrinsic neuronal excitability and seizure-like activity. It further suggests that seizures can be controlled without significantly compromising intrinsic neuronal activity and determines the required fold over IC50 for novel and clinically relevant Nav channel blockers to produce efficacy and limit side effects.
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Affiliation(s)
- Samrat Thouta
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Matthew G. Waldbrook
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Sophia Lin
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Arjun Mahadevan
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Janette Mezeyova
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Maegan Soriano
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Pareesa Versi
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Samuel J. Goodchild
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - R. Ryley Parrish
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT, United States
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Modulating effects of FGF12 variants on Na V1.2 and Na V1.6 being associated with developmental and epileptic encephalopathy and Autism spectrum disorder: A case series. EBioMedicine 2022; 83:104234. [PMID: 36029553 PMCID: PMC9429545 DOI: 10.1016/j.ebiom.2022.104234] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 08/05/2022] [Accepted: 08/05/2022] [Indexed: 01/18/2023] Open
Abstract
OBJECTIVE Fibroblast Growth Factor 12 (FGF12) may represent an important modulator of neuronal network activity and has been associated with developmental and epileptic encephalopathy (DEE). We sought to identify the underlying pathomechanism of FGF12-related disorders. METHODS Patients with pathogenic variants in FGF12 were identified through published case reports, GeneMatcher and whole exome sequencing of own case collections. The functional consequences of two missense and two copy number variants (CNVs) were studied by co-expression of wildtype and mutant FGF12 in neuronal-like cells (ND7/23) with the sodium channels NaV1.2 or NaV1.6, including their beta-1 and beta-2 sodium channel subunits (SCN1B and SCN2B). RESULTS Four variants in FGF12 were identified for functional analysis: one novel FGF12 variant in a patient with autism spectrum disorder and three variants from previously published patients affected by DEE. We demonstrate the differential regulating effects of wildtype and mutant FGF12 on NaV1.2 and NaV1.6 channels. Here, FGF12 variants lead to a complex kinetic influence on NaV1.2 and NaV1.6, including loss- as well as gain-of function changes in fast and slow inactivation. INTERPRETATION We could demonstrate the detailed regulating effect of FGF12 on NaV1.2 and NaV1.6 and confirmed the complex effect of FGF12 on neuronal network activity. Our findings expand the phenotypic spectrum related to FGF12 variants and elucidate the underlying pathomechanism. Specific variants in FGF12-associated disorders may be amenable to precision treatment with sodium channel blockers. FUNDING DFG, BMBF, Hartwell Foundation, National Institute for Neurological Disorders and Stroke, IDDRC, ENGIN, NIH, ITMAT, ILAE, RES and GRIN.
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Zhu M, Wang Y, Guan L, Lu C, Sun R, Chen Y, Shi J, Zhu Y, Wang D. A novel chromosome 2q24.3-q32.1 microdeletion in a fetus with multiple malformations. J Clin Lab Anal 2022; 36:e24602. [PMID: 35819063 PMCID: PMC9396185 DOI: 10.1002/jcla.24602] [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: 03/08/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Terminal or interstitial deletion of chromosome 2q is rarely reported but clinically significant, which can result in developmental malformations and psychomotor retardation in humans. In the present study, we analyzed this deletion to comprehensively clarify the relationship between phenotype and microdeletion region. METHODS We collected clinical records of the fetus and summarized patient symptoms. Subsequently, genomic DNA was extracted from fetal tissue or peripheral blood collected from parents. In addition, whole-exome sequencing (WES) and copy number variation sequencing (CNV-seq) were performed. RESULTS The fetus presented a previously unreported interstitial deletion of 2q24.3-q32.1. WES and CNV-seq revealed a de novo 18.46 Mb deletion at 2q24.3-q32.1, a region involving 94 protein-coding genes, including HOXD13, MAP3K20, DLX1, DLX2, SCN2A, and SCN1A. The fetus had upper and lower limb malformations, including camptodactyly and syndactyly, along with congenital cardiac defects. CONCLUSION Herein, we report a fetus with a novel microdeletion of chromosome 2q24.3-q32.1, likely a heterozygous pathogenic variant. Haploinsufficiency of HOXD13 might be related to limb deformity in the fetus.
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Affiliation(s)
- Mianmian Zhu
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yihong Wang
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Lijie Guan
- Department of Ultrasound imaging, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Chaosheng Lu
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Rongyue Sun
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yuan Chen
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jiamin Shi
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yanying Zhu
- Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Dan Wang
- Department of Pediatrics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
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50
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Zybura AS, Sahoo FK, Hudmon A, Cummins TR. CaMKII Inhibition Attenuates Distinct Gain-of-Function Effects Produced by Mutant Nav1.6 Channels and Reduces Neuronal Excitability. Cells 2022; 11:2108. [PMID: 35805192 PMCID: PMC9266207 DOI: 10.3390/cells11132108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/16/2022] [Accepted: 06/27/2022] [Indexed: 11/17/2022] Open
Abstract
Aberrant Nav1.6 activity can induce hyperexcitability associated with epilepsy. Gain-of-function mutations in the SCN8A gene encoding Nav1.6 are linked to epilepsy development; however, the molecular mechanisms mediating these changes are remarkably heterogeneous and may involve post-translational regulation of Nav1.6. Because calcium/calmodulin-dependent protein kinase II (CaMKII) is a powerful modulator of Nav1.6 channels, we investigated whether CaMKII modulates disease-linked Nav1.6 mutants. Whole-cell voltage clamp recordings in ND7/23 cells show that CaMKII inhibition of the epilepsy-related mutation R850Q largely recapitulates the effects previously observed for WT Nav1.6. We also characterized a rare missense variant, R639C, located within a regulatory hotspot for CaMKII modulation of Nav1.6. Prediction software algorithms and electrophysiological recordings revealed gain-of-function effects for R639C mutant channel activity, including increased sodium currents and hyperpolarized activation compared to WT Nav1.6. Importantly, the R639C mutation ablates CaMKII phosphorylation at a key regulatory site, T642, and, in contrast to WT and R850Q channels, displays a distinct response to CaMKII inhibition. Computational simulations demonstrate that modeled neurons harboring the R639C or R850Q mutations are hyperexcitable, and simulating the effects of CaMKII inhibition on Nav1.6 activity in modeled neurons differentially reduced hyperexcitability. Acute CaMKII inhibition may represent a promising mechanism to attenuate gain-of-function effects produced by Nav1.6 mutations.
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Affiliation(s)
- Agnes S. Zybura
- Program in Medical Neuroscience, Paul and Carole Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
| | - Firoj K. Sahoo
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; (F.K.S.); (A.H.)
| | - Andy Hudmon
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; (F.K.S.); (A.H.)
| | - Theodore R. Cummins
- Program in Medical Neuroscience, Paul and Carole Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Biology Department, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202, USA
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