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Wang C, Guo X, Long D, Li Y, Yuan C, Ni G, Zhang H, Li X, Yin S, Peng X, Huang W, Chen S, Liu Y, Chen Z. Familial mesial temporal lobe epilepsy phenotype is associated with novel LGI1 variants: A report of two families. Seizure 2024; 120:180-188. [PMID: 39029408 DOI: 10.1016/j.seizure.2024.07.005] [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: 03/12/2024] [Revised: 07/02/2024] [Accepted: 07/02/2024] [Indexed: 07/21/2024] Open
Abstract
OBJECTIVE To expand the clinical phenotype and mutation spectrum of familial mesial temporal lobe epilepsy (FMTLE) and provide a new perspective for exploring the pathological mechanisms of epilepsy caused by leucine-rich glioma inactivated 1 (LGI1) variants. METHODS We reported clinical data from two families with FMTLE and screened patients for variants in the LGI1 gene using Whole-exome sequencing and Sanger sequencing. The clinical features of FMTLE were analysed. The pathogenicity of the causative loci was assessed according to the American College of Medical Genetics and Genomics guidelines, and potential pathogenic mechanisms were predicted through multiple bioinformatics and molecular dynamics software. RESULTS We identified two novel LGI1 truncating variants within two large families with FMTLE: LGI1 (c.1174C>T, p.Q392X) and LGI1 (c.703C>T, p.Q235X). Compared to previous reports, we found that focal to bilateral tonic-clonic seizures are a common type of seizure in FMTLE. The clinical phenotypes of patients with FMTLE caused by LGI1 variants were relatively mild, and all patients responded well to valproic acid. Bioinformatics analyses and molecular dynamics simulations showed that protein structure and interactions were considerably weakened or damaged as a result of both variants. CONCLUSION This study presents the first report identifying LGI1 as a potential novel pathogenic gene within FMTLE families, thereby broadening the mutation spectrum associated with FMTLE. The findings of this study offer novel insights and avenues for understanding the intricate molecular mechanisms underlying LGI1 variants and their correlations with patient phenotypes. This study proposes the possibility of familial focal epilepsy syndromes overlapping.
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Affiliation(s)
- Chengzhe Wang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Xintong Guo
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Dingju Long
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Yinchao Li
- Department of Neurology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518107, PR China
| | - Cai Yuan
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, PR China
| | - Guanzhong Ni
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Heyu Zhang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Xi Li
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China; Department of Neurology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518107, PR China
| | - Sijing Yin
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China; Department of Neurology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518107, PR China
| | - Xinxin Peng
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China; Department of Neurology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518107, PR China
| | - Wenyao Huang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Siqing Chen
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China
| | - Yue Liu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China; Department of Neurology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518107, PR China
| | - Ziyi Chen
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou 510080, PR China.
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Yang Y, Tuo J, Zhang J, Xu Z, Luo Z. Pathogenic genes implicated in sleep-related hypermotor epilepsy: a research progress update. Front Neurol 2024; 15:1416648. [PMID: 38966089 PMCID: PMC11222571 DOI: 10.3389/fneur.2024.1416648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 06/11/2024] [Indexed: 07/06/2024] Open
Abstract
Sleep-related hypermotor epilepsy (SHE) is a focal epilepsy syndrome characterized by a variable age of onset and heterogeneous etiology. Current literature suggests a prevalence rate of approximately 1.8 per 100,000 persons. The discovery of additional pathogenic genes associated with SHE in recent years has significantly expanded the knowledge and understanding of its pathophysiological mechanisms. Identified SHE pathogenic genes include those related to neuronal ligand- and ion-gated channels (CHRNA4, CHRNB2, CHRNA2, GABRG2, and KCNT1), genes upstream of the mammalian target of rapamycin complex 1 signal transduction pathway (DEPDC5, NPRL2, NPRL3, TSC1, and TSC2), and other genes (CRH, CaBP4, STX1B, and PRIMA1). These genes encode proteins associated with ion channels, neurotransmitter receptors, cell signal transduction, and synaptic transmission. Mutations in these genes can result in the dysregulation of encoded cellular functional proteins and downstream neuronal dysfunction, ultimately leading to epileptic seizures. However, the associations between most genes and the SHE phenotype remain unclear. This article presents a literature review on the research progress of SHE-related pathogenic genes to contribute evidence to genotype-phenotype correlations in SHE and establish the necessary theoretical basis for future SHE treatments.
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Affiliation(s)
- Yufang Yang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Jinmei Tuo
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Department of Nursing, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Jun Zhang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Zucai Xu
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Zhong Luo
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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Wang R, Zhu W, Liang G, Xu J, Guo J, Wang L. Animal models for epileptic foci localization, seizure detection, and prediction by electrical impedance tomography. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2022; 13:e1619. [PMID: 36093634 DOI: 10.1002/wcs.1619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/08/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
Surgical resection of lesions and closed-loop suppression are the two main treatment options for patients with refractory epilepsy whose symptoms cannot be managed with medicines. Unfortunately, failures in foci localization and seizure prediction are constraining these treatments. Electrical impedance tomography (EIT), sensitive to impedance changes caused by blood flow or cell swelling, is a potential new way to locate epileptic foci and predict seizures. Animal validation is a necessary research process before EIT can be used in clinical practice, but it is unclear which among the many animal epilepsy models is most suited to this task. The selection of an animal model of epilepsy that is similar to human seizures and can be adapted to EIT is important for the accuracy and reliability of EIT research results. This study provides an overview of the animal models of epilepsy that have been used in research on the use of EIT to locate the foci or predict seizures; discusses the advantages and disadvantages of these models regarding inducement by chemical convulsant and electrical stimulation; and finally proposes optimal animal models of epilepsy to obtain more convincing research results for foci localization and seizure prediction by EIT. The ultimate goal of this study is to facilitate the development of new treatments for patients with refractory epilepsy. This article is categorized under: Neuroscience > Clinical Neuroscience Psychology > Brain Function and Dysfunction.
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Affiliation(s)
- Rong Wang
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Wenjing Zhu
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Guohua Liang
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Jiaming Xu
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Jie Guo
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Lei Wang
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
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Chen Z, Luo S, Liu ZG, Deng YC, He SL, Liu XR, Yi YH, Wang J, Gao LD, Li BM, Wu ZJ, Ye ZL, Liang DH, Bian WJ, Liao WP. CELSR1 variants are associated with partial epilepsy of childhood. Am J Med Genet B Neuropsychiatr Genet 2022; 189:247-256. [PMID: 36453712 DOI: 10.1002/ajmg.b.32916] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 01/25/2022] [Accepted: 07/26/2022] [Indexed: 02/01/2023]
Abstract
CELSR1 gene, encoding cadherin EGF LAG seven-pass G-type receptor 1, is mainly expressed in neural stem cells during the embryonic period. It plays an important role in neurodevelopment. However, the relationship between CELSR1 and disease of the central nervous system has not been defined. In this study, we performed trios-based whole-exome sequencing in a cohort of 356 unrelated cases with partial epilepsy without acquired causes and identified CELSR1 variants in six unrelated cases. The variants included one de novo heterozygous nonsense variant, one de novo heterozygous missense variant, and four compound heterozygous missense variants that had one variant was located in the extracellular region and the other in the cytoplasm. The patients with biallelic variants presented severe epileptic phenotypes, whereas those with heterozygous variants were associated with a mild epileptic phenotype of benign epilepsy with centrotemporal spikes (BECTS). These variants had no or low allele frequency in the gnomAD database. The frequencies of the CELSR1 variants in this cohort were significantly higher than those in the control populations. The evidence from ClinGen Clinical-Validity Framework suggested a strong association between CELSR1 variants and epilepsy. These findings provide evidence that CELSR1 is potentially a candidate pathogenic gene of partial epilepsy of childhood.
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Affiliation(s)
- Zheng Chen
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China.,Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Sheng Luo
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Zhi-Gang Liu
- Department of Pediatrics, Affiliated Foshan Maternity and Child Healthcare Hospital, Southern Medical University, Foshan, China
| | - Yan-Chun Deng
- Department of Neurology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Su-Li He
- Department of Pediatrics, Shantou Chaonan Minsheng Hospital, Shantou, China
| | - Xiao-Rong Liu
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Yong-Hong Yi
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Jie Wang
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Liang-Di Gao
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Bing-Mei Li
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Zhi-Jun Wu
- Department of Neurology, Second Hospital of Lanzhou University, Lanzhou University, Lanzhou, China
| | - Zi-Long Ye
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - De-Hai Liang
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Wen-Jun Bian
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
| | - Wei-Ping Liao
- Institute of Neuroscience, Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, The Ministry of Education of China, Guangzhou, China
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Baudin P, Cousyn L, Navarro V. The LGI1 protein: molecular structure, physiological functions and disruption-related seizures. Cell Mol Life Sci 2021; 79:16. [PMID: 34967933 PMCID: PMC11072701 DOI: 10.1007/s00018-021-04088-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 01/16/2023]
Abstract
Leucine-rich, glioma inactivated 1 (LGI1) is a secreted glycoprotein, mainly expressed in the brain, and involved in central nervous system development and physiology. Mutations of LGI1 have been linked to autosomal dominant lateral temporal lobe epilepsy (ADLTE). Recently auto-antibodies against LGI1 have been described as the basis for an autoimmune encephalitis, associated with specific motor and limbic epileptic seizures. It is the second most common cause of autoimmune encephalitis. This review presents details on the molecular structure, expression and physiological functions of LGI1, and examines how their disruption underlies human pathologies. Knock-down of LGI1 in rodents reveals that this protein is necessary for normal brain development. In mature brains, LGI1 is associated with Kv1 channels and AMPA receptors, via domain-specific interaction with membrane anchoring proteins and contributes to regulation of the expression and function of these channels. Loss of function, due to mutations or autoantibodies, of this key protein in the control of neuronal activity is a common feature in the genesis of epileptic seizures in ADLTE and anti-LGI1 autoimmune encephalitis.
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Affiliation(s)
- Paul Baudin
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
| | - Louis Cousyn
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
- AP-HP, Epilepsy Unit, Pitié-Salpêtrière Hospital, DMU Neurosciences, Paris, France
| | - Vincent Navarro
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France.
- AP-HP, Epilepsy Unit, Pitié-Salpêtrière Hospital, DMU Neurosciences, Paris, France.
- AP-HP, Center of Reference for Rare Epilepsies, Pitié-Salpêtrière Hospital, 47-83 Boulevard de l'Hôpital, 75013, Paris, France.
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6
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Okada M. Can rodent models elucidate the pathomechanisms of genetic epilepsy? Br J Pharmacol 2021; 179:1620-1639. [PMID: 33689168 PMCID: PMC9291625 DOI: 10.1111/bph.15443] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 02/03/2021] [Accepted: 03/04/2021] [Indexed: 12/31/2022] Open
Abstract
Autosomal dominant sleep-related hypermotor epilepsy (ADSHE; previously autosomal dominant nocturnal frontal lobe epilepsy, ADNFLE), originally reported in 1994, was the first distinct genetic epilepsy shown to be caused by CHNRA4 mutation. In the past two decades, we have identified several functional abnormalities of mutant ion channels and their associated transmissions using several experiments involving single-cell and genetic animal (rodent) models. Currently, epileptologists understand that functional abnormalities underlying epileptogenesis/ictogenesis in humans and rodents are more complicated than previously believed and that the function of mutant molecules alone cannot contribute to the development of epileptogenesis/ictogenesis but play important roles in the development of epileptogenesis/ictogenesis through formation of abnormalities in various other transmission systems before epilepsy onset. Based on our recent findings using genetic rat ADSHE models, harbouring Chrna4 mutant, corresponding to human S284L-mutant CRHNA4, this review proposes a hypothesis associated with tripartite synaptic transmission in ADSHE pathomechanisms induced by mutant ACh receptors.
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Affiliation(s)
- Motohiro Okada
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of Medicine, Mie University, Tsu, Japan
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Lack of Association of Generic Brittle Status with Genetics and Physiologic Measures in Patients with Epilepsy. Pharm Res 2020; 37:60. [PMID: 32103380 DOI: 10.1007/s11095-020-2781-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/07/2020] [Indexed: 10/24/2022]
Abstract
PURPOSE A patient was denoted to be generic brittle (GB) if they had a negative opinion about generics (e.g. prior history of a switch problem) or took the innovator brand of their most problematic anti-epileptic drug (AED) when generic was available. The aim of this hypothesis-generating study was to assess possible genetic and physiologic differences between GB and not GB patients with epilepsy. METHODS Patients (n = 148) with epilepsy were previously characterized as being either GB or not GB. Blood was collected from each subject for genotyping and physiologic testing. Genotyping for 24 single nucleotide polymorphisms (SNPs) and two copy number variants (CNVs) was performed across 12 genes in each patient. Forty-four physiologic tests were conducted in each patient. Chi square analysis was performed to assess for associations between genotyping results and GB status, as well as between physiologic test results and GB status. RESULTS No SNP or CNV discriminated GB status in genetic analysis (genotype or allele frequency). Physiologic test results in this study were not associated with GB status. CONCLUSIONS Questions from neurologists and patients about generics is frequently based on applicability of generic drug standards to individual subjects. However, findings here in patients with epilepsy did not uncover genetic or physiologic reasons that explained which patients were GB and which were not GB.
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Dawson RE, Nieto Guil AF, Robertson LJ, Piltz SG, Hughes JN, Thomas PQ. Functional screening of GATOR1 complex variants reveals a role for mTORC1 deregulation in FCD and focal epilepsy. Neurobiol Dis 2019; 134:104640. [PMID: 31639411 DOI: 10.1016/j.nbd.2019.104640] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 10/07/2019] [Accepted: 10/13/2019] [Indexed: 12/20/2022] Open
Abstract
Mutations in the GAP activity toward RAGs 1 (GATOR1) complex genes (DEPDC5, NPRL2 and NPRL3) have been associated with focal epilepsy and focal cortical dysplasia (FCD). GATOR1 functions as an inhibitor of the mTORC1 signalling pathway, indicating that the downstream effects of mTORC1 deregulation underpin the disease. However, the vast majority of putative disease-causing variants have not been functionally assessed for mTORC1 repression activity. Here, we develop a novel in vitro functional assay that enables rapid assessment of GATOR1-gene variants. Surprisingly, of the 17 variants tested, we show that only six showed significantly impaired mTORC1 inhibition. To further investigate variant function in vivo, we generated a conditional Depdc5 mouse which modelled a 'second-hit' mechanism of disease. Generation of Depdc5 null 'clones' in the embryonic brain resulted in mTORC1 hyperactivity and modelled epilepsy and FCD symptoms including large dysmorphic neurons, defective migration and lower seizure thresholds. Using this model, we validated DEPDC5 variant F164del to be loss-of-function. We also show that Q542P is not functionally compromised in vivo, consistent with our in vitro findings. Overall, our data show that mTORC1 deregulation is the central pathological mechanism for GATOR1 variants and also indicates that a significant proportion of putative disease variants are pathologically inert, highlighting the importance of GATOR1 variant functional assessment.
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Affiliation(s)
- Ruby E Dawson
- School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia.
| | - Alvaro F Nieto Guil
- School of Medicine, University of Adelaide, Adelaide, SA 5005, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia.
| | - Louise J Robertson
- School of Medicine, University of Adelaide, Adelaide, SA 5005, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia.
| | - Sandra G Piltz
- School of Medicine, University of Adelaide, Adelaide, SA 5005, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia.
| | - James N Hughes
- School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia.
| | - Paul Q Thomas
- School of Medicine, University of Adelaide, Adelaide, SA 5005, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia; Precision Medicine Theme, South Australia Health and Medical Research Institute, Adelaide, SA 5000, Australia.
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Neale SA, Kambara K, Salt TE, Bertrand D. Receptor variants and the development of centrally acting medications. DIALOGUES IN CLINICAL NEUROSCIENCE 2019. [PMID: 31636489 PMCID: PMC6787545 DOI: 10.31887/dcns.2019.21.2/dbertrand] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The progressive changes in research paradigms observed in the largest
pharmaceutical companies and the burgeoning of biotechnology startups over the
last 10 years have generated a need for outsourcing research facilities. In
parallel, progress made in the fields of genomics, protein expression in
recombinant systems, and electrophysiological recording methods have offered new
possibilities for the development of contract research organizations (CROs).
Successful partnering between pharmaceutical companies and CROs largely depends
upon the competences and scientific quality on offer for the discovery of novel
active molecules and targets. Thus, it is critical to review the knowledge in
the field of neuroscience research, how genetic approaches are augmenting our
knowledge, and how they can be applied in the translation from the
identification of potential molecules up to the first clinical trials. Taking
these together, it is apparent that CROs have an important role to play in the
neuroscience of drug discovery.
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Affiliation(s)
- Stuart A Neale
- Neurexpert Limited, The Core, Science Central, Newcastle Upon Tyne, UK
| | | | - Thomas E Salt
- Neurexpert Limited, The Core, Science Central, Newcastle Upon Tyne, UK; Honorary Professor, University of Newcastle, Newcastle, UK
| | - Daniel Bertrand
- HiQScreen Sàrl, Geneva, Switzerland; Emeritus Professor, Medical Faculty, Geneva, Switzerland
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Indurthi DC, Qudah T, Liao VW, Ahring PK, Lewis TM, Balle T, Chebib M, Absalom NL. Revisiting autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) mutations in the nicotinic acetylcholine receptor reveal an increase in efficacy regardless of stochiometry. Pharmacol Res 2019; 139:215-227. [DOI: 10.1016/j.phrs.2018.11.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 11/21/2018] [Accepted: 11/21/2018] [Indexed: 12/22/2022]
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Zhou K, Cherra SJ, Goncharov A, Jin Y. Asynchronous Cholinergic Drive Correlates with Excitation-Inhibition Imbalance via a Neuronal Ca 2+ Sensor Protein. Cell Rep 2018; 19:1117-1129. [PMID: 28494862 DOI: 10.1016/j.celrep.2017.04.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 03/13/2017] [Accepted: 04/15/2017] [Indexed: 10/19/2022] Open
Abstract
Excitation-inhibition imbalance in neural networks is widely linked to neurological and neuropsychiatric disorders. However, how genetic factors alter neuronal activity, leading to excitation-inhibition imbalance, remains unclear. Here, using the C. elegans locomotor circuit, we examine how altering neuronal activity for varying time periods affects synaptic release pattern and animal behavior. We show that while short-duration activation of excitatory cholinergic neurons elicits a reversible enhancement of presynaptic strength, persistent activation results to asynchronous and reduced cholinergic drive, inducing imbalance between endogenous excitation and inhibition. We find that the neuronal calcium sensor protein NCS-2 is required for asynchronous cholinergic release in an activity-dependent manner and dampens excitability of inhibitory neurons non-cell autonomously. The function of NCS-2 requires its Ca2+ binding and membrane association domains. These results reveal a synaptic mechanism implicating asynchronous release in regulation of excitation-inhibition balance.
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Affiliation(s)
- Keming Zhou
- Division of Biological Sciences, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Salvatore J Cherra
- Division of Biological Sciences, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Alexandr Goncharov
- Division of Biological Sciences, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yishi Jin
- Division of Biological Sciences, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA.
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Minjarez B, Camarena H, Haramati J, Rodríguez-Yañez Y, Mena-Munguía S, Buriticá J, García-Leal O. Behavioral changes in models of chemoconvulsant-induced epilepsy: A review. Neurosci Biobehav Rev 2017; 83:373-380. [DOI: 10.1016/j.neubiorev.2017.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 10/10/2017] [Accepted: 10/17/2017] [Indexed: 11/25/2022]
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Ferri L, Bisulli F, Mai R, Licchetta L, Leta C, Nobili L, Mostacci B, Pippucci T, Tinuper P. A stereo EEG study in a patient with sleep-related hypermotor epilepsy due to DEPDC5 mutation. Seizure 2017; 53:51-54. [PMID: 29125946 DOI: 10.1016/j.seizure.2017.10.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/21/2017] [Accepted: 10/30/2017] [Indexed: 01/23/2023] Open
Abstract
PURPOSE Dishevelled EGL-10 and pleckstrin domain-containing protein 5 (DEPDC5) mutations are found in a wide spectrum of focal epilepsies ranging from epilepsy caused by malformation of cortical development to non-lesional epilepsy, including sleep-related hypermotor epilepsy (SHE). A surgical approach has been anecdotally reported in patients with DEPDC5 mutations, but most of these cases had a lesional etiology. METHODS We describe a stereo-EEG (SEEG) study in a patient with drug-resistant/non-lesional SHE. Patient was screened for known mutations associated with SHE. RESULTS SEEG disclosed bilateral synchronous and independent activity prevailing on the right central-anterior cingulate cortex, without a clear spatially defined epileptogenic zone. Due to the lack of a clear epileptogenic zone, surgery was contraindicated. Years later a DEPDC5 mutation was identified. CONCLUSION We suggest that genetic analysis should be considered before performing SEEG study in a patient with drug resistant non-lesional SHE, in the presence of seizures in wakefulness and unclear anatomo-electroclinical correlation. If DEPDC5 mutations are identified, the presurgical evaluation should be tailored to look for MRI-negative focal cortical dysplasia and a wide epileptogenic network. The appropriate management and potential benefit of surgery for genetic non-lesional epilepsy have yet to be clarified.
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Affiliation(s)
- Lorenzo Ferri
- IRCCS Bologna Institute of Neurological Sciences, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Francesca Bisulli
- IRCCS Bologna Institute of Neurological Sciences, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
| | - Roberto Mai
- "Claudio Munari" Center for Epilepsy Surgery, Niguarda Hospital, Milano, Italy
| | - Laura Licchetta
- IRCCS Bologna Institute of Neurological Sciences, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Chiara Leta
- IRCCS Bologna Institute of Neurological Sciences, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Lino Nobili
- "Claudio Munari" Center for Epilepsy Surgery, Niguarda Hospital, Milano, Italy
| | - Barbara Mostacci
- IRCCS Bologna Institute of Neurological Sciences, Bologna, Italy
| | - Tommaso Pippucci
- Medical Genetics Unit, Sant'Orsola-Malpighi University Hospital, Bologna, Italy
| | - Paolo Tinuper
- IRCCS Bologna Institute of Neurological Sciences, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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14
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McCulloch KA, Qi YB, Takayanagi-Kiya S, Jin Y, Cherra SJ. Novel Mutations in Synaptic Transmission Genes Suppress Neuronal Hyperexcitation in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2017; 7:2055-2063. [PMID: 28468816 PMCID: PMC5499116 DOI: 10.1534/g3.117.042598] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/22/2017] [Indexed: 01/29/2023]
Abstract
Acetylcholine (ACh) receptors (AChR) regulate neural circuit activity in multiple contexts. In humans, mutations in ionotropic acetylcholine receptor (iAChR) genes can cause neurological disorders, including myasthenia gravis and epilepsy. In Caenorhabditis elegans, iAChRs play multiple roles in the locomotor circuit. The cholinergic motor neurons express an ACR-2-containing pentameric AChR (ACR-2R) comprised of ACR-2, ACR-3, ACR-12, UNC-38, and UNC-63 subunits. A gain-of-function mutation in the non-α subunit gene acr-2 [acr-2(gf)] causes defective locomotion as well as spontaneous convulsions. Previous studies of genetic suppressors of acr-2(gf) have provided insights into ACR-2R composition and assembly. Here, to further understand how the ACR-2R regulates neuronal activity, we expanded the suppressor screen for acr-2(gf)-induced convulsions. The majority of these suppressor mutations affect genes that play critical roles in synaptic transmission, including two novel mutations in the vesicular ACh transporter unc-17 In addition, we identified a role for a conserved major facilitator superfamily domain (MFSD) protein, mfsd-6, in regulating neural circuit activity. We further defined a role for the sphingosine (SPH) kinase (Sphk) sphk-1 in cholinergic neuron activity, independent of previously known signaling pathways. Overall, the genes identified in our study suggest that optimal modulation of synaptic activity is balanced by the differential activities of multiple pathways, and the novel alleles provide valuable reagents to further dissect neuronal mechanisms regulating the locomotor circuit.
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Affiliation(s)
- Katherine A McCulloch
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093
| | - Yingchuan B Qi
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093
| | - Seika Takayanagi-Kiya
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093
| | - Yishi Jin
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093
- Howard Hughes Medical Institute, University of California, San Diego, La Jolla, California 92093
| | - Salvatore J Cherra
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093
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15
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Avanzini G, Mantegazza M, Terragni B, Canafoglia L, Scalmani P, Franceschetti S. The impact of genetic and experimental studies on classification and therapy of the epilepsies. Neurosci Lett 2017; 667:17-26. [PMID: 28522348 DOI: 10.1016/j.neulet.2017.05.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/12/2017] [Accepted: 05/13/2017] [Indexed: 10/19/2022]
Abstract
Different types of epilepsy are associated with gene mutations, in which seizures can be the only symptom (genetic epilepsies) or be one of the elements of complex clinical pictures that are often progressive over time (epileptic or epileptogenic encephalopathies). In epileptogenic encephalopathies, epileptic seizures and other neurological and cognitive signs are symptoms of genetically determined neuropathological or neurochemical disorders. In epileptic encephalopathies, epileptic activity itself is thought to contribute to severe cognitive and behavioral impairments above and beyond what might be expected from the underlying pathology alone. The distinction is conceptually clear and clinically relevant, as the different categories have a different prognosis in terms of both epilepsy and associated neurological and cognitive picture, but the boundaries are sometimes difficult to define in the clinical practice. Here we review the genetic epilepsies from the clinician perspective. A monogenic inheritance has been defined only in a minority of idiopathic epilepsies making improper to rename genetic the category of idiopathic epilepsies, until the presumptive multigenic mechanism will be demonstrated. A search for gene mutations must be done in any patient with candidate genetic types of epilepsy or epileptic/epileptogenic encephalopathy (e.g. familial forms) to complete the diagnostic process, define the prognosis and optimize the therapy. Advanced methods are available to express the gene variant in experimental model systems and test its effect on the properties of the affected protein, on neuronal excitability and on phenotypes in model organisms, and may help in identifying treatments with compatible action mechanisms. The influence of genetic studies on epilepsy taxonomy is now a matter of discussion: their impact on the international classification of the epilepsies will hopefully be defined soon.
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Affiliation(s)
- Giuliano Avanzini
- Dept. of Neurophysiology and Diagnostic Epileptology, Foundation IRCCS Neurological Institute C. Besta, 20133 Milan, Italy.
| | - Massimo Mantegazza
- Institute of Molecular and Cellular Pharmacology (IPMC), CNRS UMR7275, 06560, Valbonne-Sophia, Antipolis, France; University Côte d'Azur (UCA), 06560, Valbonne-Sophia, Antipolis, France
| | - Benedetta Terragni
- Dept. of Neurophysiology and Diagnostic Epileptology, Foundation IRCCS Neurological Institute C. Besta, 20133 Milan, Italy
| | - Laura Canafoglia
- Dept. of Neurophysiology and Diagnostic Epileptology, Foundation IRCCS Neurological Institute C. Besta, 20133 Milan, Italy
| | - Paolo Scalmani
- Dept. of Neurophysiology and Diagnostic Epileptology, Foundation IRCCS Neurological Institute C. Besta, 20133 Milan, Italy
| | - Silvana Franceschetti
- Dept. of Neurophysiology and Diagnostic Epileptology, Foundation IRCCS Neurological Institute C. Besta, 20133 Milan, Italy
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16
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Ma Z. Neurophysiological Analysis of the Genesis Mechanism of EEG During the Interictal and Ictal Periods Using a Multiple Neural Masses Model. Int J Neural Syst 2017. [PMID: 28639464 DOI: 10.1142/s0129065717500277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Electroencephalography (EEG) is an important method to investigate the neurophysiological mechanism underlying epileptogenesis to identify new therapies for the treatment of epilepsy. The neurophysiologically based neural mass model (NMM) can build a bridge between signal processing and neurophysiology, which can be used as a platform to explore the neurophysiological mechanism of epileptogenesis. Most EEG signals cannot be regarded as the outputs of a single NMM with identical model parameters. The outputs of NMM are simple because the diversity of neural signals in the same NMM is ignored. To improve the simulation of EEG signals, a multiple NMM is proposed, the output of which is the linear combination of the outputs of all NMMs. The NMM number is not fixed and is minimized under the premise of guaranteeing the fitting effect. Orthogonal matching pursuit is used to solve a constrained [Formula: see text] norm minimization problem for NMM number and the strength of every NMM. The results showed that the NMM number was significantly lower during the ictal period than during the interictal period, and the strength of major NMMs increased. This indicates that neural masses fuse into fewer larger neural masses with greater strength. The distribution of excitatory and inhibitory strength during the ictal and interictal periods was similar, whereas the excitation/inhibition ratio was higher during the ictal period than during the interictal period.
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Affiliation(s)
- Zhen Ma
- 1 Department of Information Engineering, Binzhou University, Binzhou 256600, P. R. China
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17
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Scholl T, Mühlebner A, Ricken G, Gruber V, Fabing A, Samueli S, Gröppel G, Dorfer C, Czech T, Hainfellner JA, Prabowo AS, Reinten RJ, Hoogendijk L, Anink JJ, Aronica E, Feucht M. Impaired oligodendroglial turnover is associated with myelin pathology in focal cortical dysplasia and tuberous sclerosis complex. Brain Pathol 2017; 27:770-780. [PMID: 27750396 PMCID: PMC5697648 DOI: 10.1111/bpa.12452] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 10/06/2016] [Indexed: 12/19/2022] Open
Abstract
Conventional antiepileptic drugs suppress the excessive firing of neurons during seizures. In drug-resistant patients, treatment failure indicates an alternative important epileptogenic trigger. Two epilepsy-associated pathologies show myelin deficiencies in seizure-related brain regions: Focal Cortical Dysplasia IIB (FCD) and cortical tubers in Tuberous Sclerosis Complex (TSC). Studies uncovering white matter-pathology mechanisms are therefore urgently needed to gain more insight into epileptogenesis, the propensity to maintain seizures, and their associated comorbidities such as cognitive defects. We analyzed epilepsy surgery specimens of FCD IIB (n = 22), TSC (n = 8), and other malformations of cortical development MCD (n = 12), and compared them to autopsy and biopsy cases (n = 15). The entire lesional pathology was assessed using digital immunohistochemistry, immunofluorescence and western blotting for oligodendroglial lineage, myelin and mTOR markers, and findings were correlated to clinical parameters. White matter pathology with depleted myelin and oligodendroglia were found in 50% of FCD IIB and 62% of TSC cases. Other MCDs had either a normal content or even showed reactive oligodendrolial hyperplasia. Furthermore, myelin deficiency was associated with increased mTOR expression and the lower amount of oligodendroglia was linked with their precursor cells (PDGFRa). The relative duration of epilepsy (normalized to age) also correlated positively to mTOR activation and negatively to myelination. Decreased content of oligodendroglia and missing precursor cells indicated insufficient oligodendroglial development, probably mediated by mTOR, which may ultimately lead to severe myelin loss. In terms of disease management, an early and targeted treatment could restore normal myelin development and, therefore, alter seizure threshold and improve cognitive outcome.
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Affiliation(s)
- Theresa Scholl
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Angelika Mühlebner
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Gerda Ricken
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Victoria Gruber
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Anna Fabing
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Sharon Samueli
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Gudrun Gröppel
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Christian Dorfer
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Thomas Czech
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | | | - Avanita S Prabowo
- Department of (Neuro) Pathology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Roy J Reinten
- Department of (Neuro) Pathology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Lisette Hoogendijk
- Department of (Neuro) Pathology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Jasper J Anink
- Department of (Neuro) Pathology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Eleonora Aronica
- Department of (Neuro) Pathology, Academic Medical Centre, Amsterdam, The Netherlands.,Swammerdam Institute for Life Sciences, Centre for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
| | - Martha Feucht
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
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18
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Liu JY, Reeves C, Diehl B, Coppola A, Al-Hajri A, Hoskote C, Mughairy SA, Tachrount M, Groves M, Michalak Z, Mills K, McEvoy AW, Miserocchi A, Sisodiya SM, Thom M. Early lipofuscin accumulation in frontal lobe epilepsy. Ann Neurol 2016; 80:882-895. [DOI: 10.1002/ana.24803] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 10/17/2016] [Accepted: 10/17/2016] [Indexed: 02/03/2023]
Affiliation(s)
- Joan Y.W. Liu
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery; London United Kingdom
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
| | - Cheryl Reeves
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery; London United Kingdom
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
| | - Beate Diehl
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
- Department of Clinical Neurophysiology; National Hospital for Neurology and Neurosurgery; London United Kingdom
| | - Antonietta Coppola
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
| | - Aliya Al-Hajri
- The Lysholm Department of Neuroradiology in National Hospital for Neurology and Neurosurgery; London United Kingdom and Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Chandrashekar Hoskote
- The Lysholm Department of Neuroradiology in National Hospital for Neurology and Neurosurgery; London United Kingdom and Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Salim al Mughairy
- The Lysholm Department of Neuroradiology in National Hospital for Neurology and Neurosurgery; London United Kingdom and Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Mohamed Tachrount
- The Lysholm Department of Neuroradiology in National Hospital for Neurology and Neurosurgery; London United Kingdom and Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Michael Groves
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery; London United Kingdom
| | - Zuzanna Michalak
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery; London United Kingdom
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
| | - Kevin Mills
- Biological Mass Spectrometry Centre, Institute of Child Health; University College London; London United Kingdom
| | - Andrew W. McEvoy
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
- Victor Horsley Department of Neurosurgery; National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Anna Miserocchi
- Victor Horsley Department of Neurosurgery; National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Sanjay M. Sisodiya
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
- Epilepsy Society, Chesham Lane; Chalfont St Peter United Kingdom
| | - Maria Thom
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery; London United Kingdom
- Department of Clinical and Experimental Epilepsy; UCL Institute of Neurology; London United Kingdom
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19
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Herrera JA, Ward CS, Wehrens XH, Neul JL. Methyl-CpG binding-protein 2 function in cholinergic neurons mediates cardiac arrhythmogenesis. Hum Mol Genet 2016; 25:4983-4995. [PMID: 28159985 PMCID: PMC6078594 DOI: 10.1093/hmg/ddw326] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/20/2016] [Accepted: 09/21/2016] [Indexed: 01/22/2023] Open
Abstract
Sudden unexpected death occurs in one quarter of deaths in Rett Syndrome (RTT), a neurodevelopmental disorder caused by mutations in Methyl-CpG-binding protein 2 (MECP2). People with RTT show a variety of autonomic nervous system (ANS) abnormalities and mouse models show similar problems including QTc interval prolongation and hypothermia. To explore the role of cardiac problems in sudden death in RTT, we characterized cardiac rhythm in mice lacking Mecp2 function. Male and female mutant mice exhibited spontaneous cardiac rhythm abnormalities including bradycardic events, sinus pauses, atrioventricular block, premature ventricular contractions, non-sustained ventricular arrhythmias, and increased heart rate variability. Death was associated with spontaneous cardiac arrhythmias and complete conduction block. Atropine treatment reduced cardiac arrhythmias in mutant mice, implicating overactive parasympathetic tone. To explore the role of MeCP2 within the parasympathetic neurons, we selectively removed MeCP2 function from cholinergic neurons (MeCP2 ChAT KO), which recapitulated the cardiac rhythm abnormalities, hypothermia, and early death seen in RTT male mice. Conversely, restoring MeCP2 only in cholinergic neurons rescued these phenotypes. Thus, MeCP2 in cholinergic neurons is necessary and sufficient for autonomic cardiac control, thermoregulation, and survival, and targeting the overactive parasympathetic system may be a useful therapeutic strategy to prevent sudden unexpected death in RTT.
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Affiliation(s)
- José A. Herrera
- Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, USA
- Jan and Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, USA
| | - Christopher S. Ward
- Jan and Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, USA
| | - Xander H.T. Wehrens
- Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, USA
- Cardiovascular Research Institute
- Departments of Medicine
- Molecular Physiology and Biophysics
- Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Jeffrey L. Neul
- Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, USA
- Jan and Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, USA
- Molecular Physiology and Biophysics
- Neuroscience
- Human and Molecular Genetics
- Pediatrics, Baylor College of Medicine, Houston, TX, USA
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20
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LGI1 acts presynaptically to regulate excitatory synaptic transmission during early postnatal development. Sci Rep 2016; 6:21769. [PMID: 26878798 PMCID: PMC4754946 DOI: 10.1038/srep21769] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 02/01/2016] [Indexed: 12/30/2022] Open
Abstract
The secreted leucine-rich glioma inactivated 1 (LGI1) protein is an important actor for human seizures of both genetic and autoimmune etiology: mutations in LGI1 cause inherited temporal lobe epilepsy, while LGI1 is involved in antibody-mediated encephalitis. Remarkably, Lgi1-deficient (Lgi1(-/-)) mice recapitulate the epileptic disorder and display early-onset spontaneous seizures. To understand how Lgi1-deficiency leads to seizures during postnatal development, we here investigated the early functional and structural defects occurring before seizure onset in Lgi1(-/-) mice. We found an increased excitatory synaptic transmission in hippocampal slices from Lgi1(-/-) mice. No structural alteration in the morphology of pyramidal cell dendrites and synapses was observed at this stage, indicating that Lgi1-deficiency is unlikely to trigger early developmental abnormalities. Consistent with the presynaptic subcellular localization of the protein, Lgi1-deficiency caused presynaptic defects, with no alteration in postsynaptic AMPA receptor activity in Lgi1-/- pyramidal cells before seizure onset. Presynaptic dysfunction led to increased synaptic glutamate levels, which were associated with hyperexcitable neuronal networks. Altogether, these data show that Lgi1 acts presynaptically as a negative modulator of excitatory synaptic transmission during early postnatal development. We therefore here reveal that increased presynaptic glutamate release is a key early event resulting from Lgi1-deficiency, which likely contributes to epileptogenesis.
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21
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Ream MA, Patel AD. Obtaining genetic testing in pediatric epilepsy. Epilepsia 2015; 56:1505-14. [DOI: 10.1111/epi.13122] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2015] [Indexed: 12/11/2022]
Affiliation(s)
- Margie A. Ream
- Nationwide Children's Hospital; Columbus Ohio U.S.A
- The Ohio State University College of Medicine; Columbus Ohio U.S.A
| | - Anup D. Patel
- Nationwide Children's Hospital; Columbus Ohio U.S.A
- The Ohio State University College of Medicine; Columbus Ohio U.S.A
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