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Ramirez-Franco J, Debreux K, Sangiardi M, Belghazi M, Kim Y, Lee SH, Lévêque C, Seagar M, El Far O. The downregulation of Kv 1 channels in Lgi1 -/-mice is accompanied by a profound modification of its interactome and a parallel decrease in Kv 2 channels. Neurobiol Dis 2024; 196:106513. [PMID: 38663634 DOI: 10.1016/j.nbd.2024.106513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 03/12/2024] [Accepted: 04/23/2024] [Indexed: 05/03/2024] Open
Abstract
In animal models of LGI1-dependent autosomal dominant lateral temporal lobe epilepsy, Kv1 channels are downregulated, suggesting their crucial involvement in epileptogenesis. The molecular basis of Kv1 channel-downregulation in LGI1 knock-out mice has not been elucidated and how the absence of this extracellular protein induces an important modification in the expression of Kv1 remains unknown. In this study we analyse by immunofluorescence the modifications in neuronal Kv1.1 and Kv1.2 distribution throughout the hippocampal formation of LGI1 knock-out mice. We show that Kv1 downregulation is not restricted to the axonal compartment, but also takes place in the somatodendritic region and is accompanied by a drastic decrease in Kv2 expression levels. Moreover, we find that the downregulation of these Kv channels is associated with a marked increase in bursting patterns. Finally, mass spectrometry uncovered key modifications in the Kv1 interactome that highlight the epileptogenic implication of Kv1 downregulation in LGI1 knock-out animals.
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Affiliation(s)
- Jorge Ramirez-Franco
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, Aix-Marseille Université, 13015 Marseille, France.
| | - Kévin Debreux
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, Aix-Marseille Université, 13015 Marseille, France
| | - Marion Sangiardi
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, Aix-Marseille Université, 13015 Marseille, France
| | - Maya Belghazi
- Marseille Protéomique (MaP), Plateforme Protéomique IMM, CNRS FR3479, Aix-Marseille Université, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Yujin Kim
- Department of Physiology, Cell Physiology Lab, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, South Korea
| | - Suk-Ho Lee
- Department of Physiology, Cell Physiology Lab, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, South Korea
| | - Christian Lévêque
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, Aix-Marseille Université, 13015 Marseille, France
| | - Michael Seagar
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, Aix-Marseille Université, 13015 Marseille, France
| | - Oussama El Far
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, Aix-Marseille Université, 13015 Marseille, France.
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2
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Cuhadar U, Calzado-Reyes L, Pascual-Caro C, Aberra AS, Ritzau-Jost A, Aggarwal A, Ibata K, Podgorski K, Yuzaki M, Geis C, Hallerman S, Hoppa MB, de Juan-Sanz J. Activity-driven synaptic translocation of LGI1 controls excitatory neurotransmission. Cell Rep 2024; 43:114186. [PMID: 38700985 PMCID: PMC11156761 DOI: 10.1016/j.celrep.2024.114186] [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: 06/28/2022] [Revised: 12/14/2023] [Accepted: 04/17/2024] [Indexed: 05/05/2024] Open
Abstract
The fine control of synaptic function requires robust trans-synaptic molecular interactions. However, it remains poorly understood how trans-synaptic bridges change to reflect the functional states of the synapse. Here, we develop optical tools to visualize in firing synapses the molecular behavior of two trans-synaptic proteins, LGI1 and ADAM23, and find that neuronal activity acutely rearranges their abundance at the synaptic cleft. Surprisingly, synaptic LGI1 is primarily not secreted, as described elsewhere, but exo- and endocytosed through its interaction with ADAM23. Activity-driven translocation of LGI1 facilitates the formation of trans-synaptic connections proportionally to the history of activity of the synapse, adjusting excitatory transmission to synaptic firing rates. Accordingly, we find that patient-derived autoantibodies against LGI1 reduce its surface fraction and cause increased glutamate release. Our findings suggest that LGI1 abundance at the synaptic cleft can be acutely remodeled and serves as a critical control point for synaptic function.
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Affiliation(s)
- Ulku Cuhadar
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, 75013 Paris, France
| | - Lorenzo Calzado-Reyes
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, 75013 Paris, France
| | - Carlos Pascual-Caro
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, 75013 Paris, France
| | - Aman S Aberra
- Department of Biology, Dartmouth College, Hanover, NH 03755, USA
| | - Andreas Ritzau-Jost
- Carl-Ludwig-Institute of Physiology, Faculty of Medicine, Leipzig University, 04317 Leipzig, Germany
| | - Abhi Aggarwal
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Keiji Ibata
- Department of Neurophysiology, Keio University, Tokyo 160-8582, Japan
| | | | - Michisuke Yuzaki
- Department of Neurophysiology, Keio University, Tokyo 160-8582, Japan
| | - Christian Geis
- Department of Neurology, Section Translational Neuroimmunology, Jena University Hospital, 07747 Jena, Germany
| | - Stefan Hallerman
- Carl-Ludwig-Institute of Physiology, Faculty of Medicine, Leipzig University, 04317 Leipzig, Germany
| | - Michael B Hoppa
- Department of Biology, Dartmouth College, Hanover, NH 03755, USA
| | - Jaime de Juan-Sanz
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, 75013 Paris, France.
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3
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Miyazaki Y, Otsuka T, Yamagata Y, Endo T, Sanbo M, Sano H, Kobayashi K, Inahashi H, Kornau HC, Schmitz D, Prüss H, Meijer D, Hirabayashi M, Fukata Y, Fukata M. Oligodendrocyte-derived LGI3 and its receptor ADAM23 organize juxtaparanodal Kv1 channel clustering for short-term synaptic plasticity. Cell Rep 2024; 43:113634. [PMID: 38194969 PMCID: PMC10828548 DOI: 10.1016/j.celrep.2023.113634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/31/2023] [Accepted: 12/14/2023] [Indexed: 01/11/2024] Open
Abstract
Neurodevelopmental disorders, such as intellectual disability (ID), epilepsy, and autism, involve altered synaptic transmission and plasticity. Functional characterization of their associated genes is vital for understanding physio-pathological brain functions. LGI3 is a recently recognized ID-associated gene encoding a secretory protein related to an epilepsy-gene product, LGI1. Here, we find that LGI3 is uniquely secreted from oligodendrocytes in the brain and enriched at juxtaparanodes of myelinated axons, forming nanoscale subclusters. Proteomic analysis using epitope-tagged Lgi3 knockin mice shows that LGI3 uses ADAM23 as a receptor and selectively co-assembles with Kv1 channels. A lack of Lgi3 in mice disrupts juxtaparanodal clustering of ADAM23 and Kv1 channels and suppresses Kv1-channel-mediated short-term synaptic plasticity. Collectively, this study identifies an extracellular organizer of juxtaparanodal Kv1 channel clustering for finely tuned synaptic transmission. Given the defective secretion of the LGI3 missense variant, we propose a molecular pathway, the juxtaparanodal LGI3-ADAM23-Kv1 channel, for understanding neurodevelopmental disorders.
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Affiliation(s)
- Yuri Miyazaki
- Division of Neuropharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan; Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Takeshi Otsuka
- Section of Cellular Electrophysiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan
| | - Yoko Yamagata
- Section of Multilayer Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | | | - Makoto Sanbo
- Section of Mammalian Transgenesis, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Hiromi Sano
- Division of Behavioral Neuropharmacology, International Center for Brain Science, Fujita Health University, Toyoake, Aichi 470-1192, Japan
| | - Kenta Kobayashi
- Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan; Section of Viral Vector Development, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | - Hiroki Inahashi
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Hans-Christian Kornau
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Neuroscience Research Center (NWFZ), Cluster NeuroCure, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dietmar Schmitz
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Neuroscience Research Center (NWFZ), Cluster NeuroCure, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Harald Prüss
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany; Helmholtz Innovation Lab BaoBab (Brain Antibody-omics and B-cell Lab), Berlin, Germany; Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dies Meijer
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, UK
| | - Masumi Hirabayashi
- Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan; Section of Mammalian Transgenesis, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Yuko Fukata
- Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Division of Molecular and Cellular Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan.
| | - Masaki Fukata
- Division of Neuropharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan; Division of Membrane Physiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan.
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4
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Extrémet J, Ramirez-Franco J, Fronzaroli-Molinieres L, Boumedine-Guignon N, Ankri N, El Far O, Garrido JJ, Debanne D, Russier M. Rescue of Normal Excitability in LGI1-Deficient Epileptic Neurons. J Neurosci 2023; 43:8596-8606. [PMID: 37863654 PMCID: PMC10727174 DOI: 10.1523/jneurosci.0701-23.2023] [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: 04/19/2023] [Revised: 09/08/2023] [Accepted: 10/14/2023] [Indexed: 10/22/2023] Open
Abstract
Leucine-rich glioma inactivated 1 (LGI1) is a glycoprotein secreted by neurons, the deletion of which leads to autosomal dominant lateral temporal lobe epilepsy. We previously showed that LGI1 deficiency in a mouse model (i.e., knock-out for LGI1 or KO-Lgi1) decreased Kv1.1 channel density at the axon initial segment (AIS) and at presynaptic terminals, thus enhancing both intrinsic excitability and glutamate release. However, it is not known whether normal excitability can be restored in epileptic neurons. Here, we show that the selective expression of LGI1 in KO-Lgi1 neurons from mice of both sexes, using single-cell electroporation, reduces intrinsic excitability and restores both the Kv1.1-mediated D-type current and Kv1.1 channels at the AIS. In addition, we show that the homeostatic-like shortening of the AIS length observed in KO-Lgi1 neurons is prevented in neurons electroporated with the Lgi1 gene. Furthermore, we reveal a spatial gradient of intrinsic excitability that is centered on the electroporated neuron. We conclude that expression of LGI1 restores normal excitability through functional Kv1 channels at the AIS.SIGNIFICANCE STATEMENT The lack of leucine-rich glioma inactivated 1 (LGI1) protein induces severe epileptic seizures that leads to death. Enhanced intrinsic and synaptic excitation in KO-Lgi1 mice is because of the decrease in Kv1.1 channels in CA3 neurons. However, the conditions to restore normal excitability profile in epileptic neurons remain to be defined. We show here that the expression of LGI1 in KO-Lgi1 neurons in single neurons reduces intrinsic excitability, and restores both the Kv1.1-mediated D-type current and Kv1.1 channels at the axon initial segment (AIS). Furthermore, the homeostatic shortening of the AIS length observed in KO-Lgi1 neurons is prevented in neurons in which the Lgi1 gene has been rescued. We conclude that LGI1 constitutes a critical factor to restore normal excitability in epileptic neurons.
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Affiliation(s)
- Johanna Extrémet
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Jorge Ramirez-Franco
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Laure Fronzaroli-Molinieres
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Norah Boumedine-Guignon
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Norbert Ankri
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Oussama El Far
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Juan José Garrido
- Cajal Institute, Consejo Superior de Investigaciones Cientificas, Madrid, 28002, Spain
| | - Dominique Debanne
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
| | - Michaël Russier
- Unité de Neurobiologie des canaux Ioniques et de la Synapse, Unité Mixte de Recherche 1072, Institut National de la Santé et de la Recherche Médicale, Aix-Marseille Université, Marseille, 13015, France
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5
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Kinboshi M, Shimizu S, Tokudome K, Mashimo T, Serikawa T, Ito H, Takahashi R, Ikeda A, Ohno Y. Imbalance of glutamatergic and GABAergic neurotransmission in audiogenic seizure-susceptible L eucine-rich glioma-inactivated 1 ( Lgi1)-mutant rats. Heliyon 2023; 9:e17984. [PMID: 37539249 PMCID: PMC10395352 DOI: 10.1016/j.heliyon.2023.e17984] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 06/26/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023] Open
Abstract
Leucine-rich glioma-inactivated 1 (LGI1) was identified as a causative gene of autosomal dominant lateral temporal lobe epilepsy. We previously reported that Lgi1-mutant rats carrying a missense mutation (L385R) showed audiogenic seizure-susceptibility. To explore the pathophysiological mechanisms underlying Lgi1-related epilepsy, we evaluated changes in glutamate and GABA release in Lgi1-mutant rats. Acoustic priming (AP) for audiogenic seizure-susceptibility was performed by applying intense sound stimulation (130 dB, 10 kHz, 5 min) on postnatal day 16. Extracellular glutamate and GABA levels in the hippocampus CA1 region were evaluated at 8 weeks of age, using in vivo microdialysis techniques. Under naïve conditions without AP, glutamate and GABA release evoked by high-K+ depolarization was more prominent in Lgi1-mutant than in wild-type (WT) rats. The AP treatment on day 16 significantly increased basal glutamate levels and depolarization-induced glutamate release both in Lgi1-mutant and WT rats, yielding greater depolarization-induced glutamate release in Lgi1-mutant rats. On the other hand, the AP treatment enhanced depolarization-induced GABA release only in WT rats, and not in Lgi1-mutant rats, illustrating reduced GABAergic neurotransmission in primed Lgi1-mutant rats. The present results suggest that enhanced glutamatergic and reduced GABAergic neurotransmission are involved in the audiogenic seizure-susceptibility associated with Lgi1-mutation.
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Affiliation(s)
- Masato Kinboshi
- Department of Pharmacology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, 569-1094, Japan
- Department of Neurology, Wakayama Medical University, Wakayama, 641-8509, Japan
- Department of Neurology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Saki Shimizu
- Department of Pharmacology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, 569-1094, Japan
| | - Kentaro Tokudome
- Department of Pharmacology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, 569-1094, Japan
| | - Tomoji Mashimo
- Laboratory Animal Research Center, Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, 108-8639, Japan
| | - Tadao Serikawa
- Department of Pharmacology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, 569-1094, Japan
| | - Hidefumi Ito
- Department of Neurology, Wakayama Medical University, Wakayama, 641-8509, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Akio Ikeda
- Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Yukihiro Ohno
- Department of Pharmacology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, 569-1094, Japan
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6
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Glantschnigg-Eisl U, Klang A, Kneissl S, Lang B, Waters P, Irani SR, Binks SNM, Pakozdy A. A feline model of spontaneously occurring autoimmune limbic encephalitis. Vet J 2023; 296-297:105974. [PMID: 36958405 DOI: 10.1016/j.tvjl.2023.105974] [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: 02/25/2022] [Revised: 03/08/2023] [Accepted: 03/20/2023] [Indexed: 03/25/2023]
Abstract
Autoimmune encephalitis (AE) is an important cause of encephalitis in humans and occurs at a similar rate to infectious encephalitis. It is frequently associated with antibodies against the extracellular domain of neuronal proteins. Among human AE, that with antibodies against leucine-rich glioma-inactivated 1 (LGI1) is one of the most prevalent forms, and was recently described in cats with limbic encephalitis (LE). In this study, we describe a large cohort (n = 32) of cats with AE, tested positive for voltage gated potassium channel (VGKC)-antibodies, of which 26 (81%) harboured LGI1-antibodies. We delineate their clinical and paraclinical features as well as long-term outcomes up to 5 years. Similar to human cases, most cats with LGI1-antibodies had a history of focal seizures (83%), clustering in the majority (88%), with interictal behavioural changes (73%). Among feline AE patients, there was no seizure type or other clinical characteristic that could distinguish LGI1-antibody positive from negative cats, unlike the pathognomic faciobrachial dystonic seizures seen in humans. Although six cats were euthanased in the first year for epilepsy-associated reasons, those attaining at least 1-year survival had good seizure control and quality of life with appropriate veterinary care and medication. Acute-phase immunotherapy (prednisolone) was given to the most severely unwell cases and its effect is retrospectively evaluated in 10 cats. Our data show LGI1-antibodies are an important cause of feline encephalitis, sharing many features with human AE. Further research should examine optimal therapeutic management strategies and the cause of LE in seronegative cats, building on paradigms established in the counterpart human disease.
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Affiliation(s)
- U Glantschnigg-Eisl
- Clinic for Small Animals, Internal Medicine, University of Veterinary Medicine Vienna, Austria.
| | - A Klang
- Institute for Pathology and Forensic Veterinary Medicine, Universitiy of Veterinary Medicine Vienna, Austria
| | - S Kneissl
- Diagnostic Imaging, University of Veterinary Medicine Vienna, Austria
| | - B Lang
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, OX3 9DU, UK
| | - P Waters
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, OX3 9DU, UK
| | - S R Irani
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, OX3 9DU, UK; Department of Neurology, John Radcliffe Hospital, Oxford University Hospitals Foundation Trust, Oxford OX3 9DU, UK
| | - S N M Binks
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, OX3 9DU, UK; Department of Neurology, John Radcliffe Hospital, Oxford University Hospitals Foundation Trust, Oxford OX3 9DU, UK
| | - A Pakozdy
- Clinic for Small Animals, Internal Medicine, University of Veterinary Medicine Vienna, Austria
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7
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Zhou L, Wang K, Xu Y, Dong BB, Wu DC, Wang ZX, Wang XT, Cai XY, Yang JT, Zheng R, Chen W, Shen Y, Wei JS. A patient-derived mutation of epilepsy-linked LGI1 increases seizure susceptibility through regulating K v1.1. Cell Biosci 2023; 13:34. [PMID: 36804022 PMCID: PMC9940402 DOI: 10.1186/s13578-023-00983-y] [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: 12/30/2022] [Accepted: 02/04/2023] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND Autosomal dominant lateral temporal epilepsy (ADLTE) is an inherited syndrome caused by mutations in the leucine-rich glioma inactivated 1 (LGI1) gene. It is known that functional LGI1 is secreted by excitatory neurons, GABAergic interneurons, and astrocytes, and regulates AMPA-type glutamate receptor-mediated synaptic transmission by binding ADAM22 and ADAM23. However, > 40 LGI1 mutations have been reported in familial ADLTE patients, more than half of which are secretion-defective. How these secretion-defective LGI1 mutations lead to epilepsy is unknown. RESULTS We identified a novel secretion-defective LGI1 mutation from a Chinese ADLTE family, LGI1-W183R. We specifically expressed mutant LGI1W183R in excitatory neurons lacking natural LGI1, and found that this mutation downregulated Kv1.1 activity, led to neuronal hyperexcitability and irregular spiking, and increased epilepsy susceptibility in mice. Further analysis revealed that restoring Kv1.1 in excitatory neurons rescued the defect of spiking capacity, improved epilepsy susceptibility, and prolonged the life-span of mice. CONCLUSIONS These results describe a role of secretion-defective LGI1 in maintaining neuronal excitability and reveal a new mechanism in the pathology of LGI1 mutation-related epilepsy.
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Affiliation(s)
- Lin Zhou
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Kang Wang
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310003 China
| | - Yuxiang Xu
- grid.256922.80000 0000 9139 560XSchool of Life Sciences, Henan University, Kaifeng, 475004 China
| | - Bin-Bin Dong
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Deng-Chang Wu
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310003 China
| | - Zhao-Xiang Wang
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Xin-Tai Wang
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Xin-Yu Cai
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Jin-Tao Yang
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Rui Zheng
- grid.13402.340000 0004 1759 700XDepartment of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020 China
| | - Wei Chen
- Department of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020, China.
| | - Ying Shen
- Department of Physiology and Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020, China.
| | - Jian-She Wei
- School of Life Sciences, Henan University, Kaifeng, 475004, China.
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8
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Ramirez-Franco J, Debreux K, Extremet J, Maulet Y, Belghazi M, Villard C, Sangiardi M, Youssouf F, El Far L, Lévêque C, Debarnot C, Marchot P, Paneva S, Debanne D, Russier M, Seagar M, Irani SR, El Far O. Patient-derived antibodies reveal the subcellular distribution and heterogeneous interactome of LGI1. Brain 2022; 145:3843-3858. [PMID: 35727946 DOI: 10.1093/brain/awac218] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/08/2022] [Accepted: 06/10/2022] [Indexed: 11/14/2022] Open
Abstract
Autoantibodies against leucine-rich glioma-inactivated 1 (LGI1) occur in patients with encephalitis who present with frequent focal seizures and a pattern of amnesia consistent with focal hippocampal damage. To investigate whether the cellular and subcellular distribution of LGI1 may explain the localization of these features, and hence gain broader insights into LGI1's neurobiology, we analysed the detailed localization of LGI1 and the diversity of its protein interactome, in mouse brains using patient-derived recombinant monoclonal LGI1 antibodies. Combined immunofluorescence and mass spectrometry analyses showed that LGI1 is enriched in excitatory and inhibitory synaptic contact sites, most densely within CA3 regions of the hippocampus. LGI1 is secreted in both neuronal somatodendritic and axonal compartments, and occurs in oligodendrocytic, neuro-oligodendrocytic and astro-microglial protein complexes. Proteomic data support the presence of LGI1-Kv1-MAGUK complexes, but did not reveal LGI1 complexes with postsynaptic glutamate receptors. Our results extend our understanding of regional, cellular and subcellular LGI1 expression profiles and reveal novel LGI1-associated complexes, thus providing insights into the complex biology of LGI1 and its relationship to seizures and memory loss.
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Affiliation(s)
- Jorge Ramirez-Franco
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Kévin Debreux
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Johanna Extremet
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Yves Maulet
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Maya Belghazi
- Aix-Marseille University, CNRS, Institute of Neurophysiopathology (INP), PINT, PFNT, 13385 cedex 5 Marseille, France
| | - Claude Villard
- Aix-Marseille University, CNRS, Institute of Neurophysiopathology (INP), PINT, PFNT, 13385 cedex 5 Marseille, France
| | - Marion Sangiardi
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Fahamoe Youssouf
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Lara El Far
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Christian Lévêque
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Claire Debarnot
- Laboratoire 'Architecture et Fonction des Macromolécules Biologiques (AFMB)', CNRS, Aix-Marseille Université, 13288 cedex 09 Marseille, France
| | - Pascale Marchot
- Laboratoire 'Architecture et Fonction des Macromolécules Biologiques (AFMB)', CNRS, Aix-Marseille Université, 13288 cedex 09 Marseille, France
| | - Sofija Paneva
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Dominique Debanne
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Michael Russier
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Michael Seagar
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
| | - Sarosh R Irani
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
- Department of Neurology, Oxford University Hospitals, Oxford, UK
| | - Oussama El Far
- INSERM, Aix-Marseille Université (AMU), UMR 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse, 13015 Marseille, France
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9
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Rodent Models of Audiogenic Epilepsy: Genetic Aspects, Advantages, Current Problems and Perspectives. Biomedicines 2022; 10:biomedicines10112934. [PMID: 36428502 PMCID: PMC9687921 DOI: 10.3390/biomedicines10112934] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
Abstract
Animal models of epilepsy are of great importance in epileptology. They are used to study the mechanisms of epileptogenesis, and search for new genes and regulatory pathways involved in the development of epilepsy as well as screening new antiepileptic drugs. Today, many methods of modeling epilepsy in animals are used, including electroconvulsive, pharmacological in intact animals, and genetic, with the predisposition for spontaneous or refractory epileptic seizures. Due to the simplicity of manipulation and universality, genetic models of audiogenic epilepsy in rodents stand out among this diversity. We tried to combine data on the genetics of audiogenic epilepsy in rodents, the relevance of various models of audiogenic epilepsy to certain epileptic syndromes in humans, and the advantages of using of rodent strains predisposed to audiogenic epilepsy in current epileptology.
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10
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Altered Extracellular Matrix as an Alternative Risk Factor for Epileptogenicity in Brain Tumors. Biomedicines 2022; 10:biomedicines10102475. [PMID: 36289737 PMCID: PMC9599244 DOI: 10.3390/biomedicines10102475] [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: 07/29/2022] [Revised: 09/23/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Seizures are one of the most common symptoms of brain tumors. The incidence of seizures differs among brain tumor type, grade, location and size, but paediatric-type diffuse low-grade gliomas/glioneuronal tumors are often highly epileptogenic. The extracellular matrix (ECM) is known to play a role in epileptogenesis and tumorigenesis because it is involved in the (re)modelling of neuronal connections and cell-cell signaling. In this review, we discuss the epileptogenicity of brain tumors with a focus on tumor type, location, genetics and the role of the extracellular matrix. In addition to functional problems, epileptogenic tumors can lead to increased morbidity and mortality, stigmatization and life-long care. The health advantages can be major if the epileptogenic properties of brain tumors are better understood. Surgical resection is the most common treatment of epilepsy-associated tumors, but post-surgery seizure-freedom is not always achieved. Therefore, we also discuss potential novel therapies aiming to restore ECM function.
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11
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Dysregulation of the hippocampal neuronal network by LGI1 auto-antibodies. PLoS One 2022; 17:e0272277. [PMID: 35984846 PMCID: PMC9390894 DOI: 10.1371/journal.pone.0272277] [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] [Received: 02/02/2022] [Accepted: 07/15/2022] [Indexed: 11/19/2022] Open
Abstract
LGI1 is a neuronal secreted protein highly expressed in the hippocampus. Epileptic seizures and LGI1 hypo-functions have been found in both ADLTE, a genetic epileptogenic syndrome and LGI1 limbic encephalitis (LE), an autoimmune disease. Studies, based mainly on transgenic mouse models, investigated the function of LGI1 in the CNS and strangely showed that LGI1 loss of function, led to a decreased AMPA-receptors (AMPA-R) expression. Our project intends at better understanding how an altered function of LGI1 leads to epileptic seizures. To reach our goal, we infused mice with LGI1 IgG purified from the serum of patients diagnozed with LGI1 LE. Super resolution imaging revealed that LGI1 IgG reduced AMPA-R expression at the surface of inhibitory and excitatory neurons only in the dentate gyrus of the hippocampus. Complementary electrophysiological approaches indicated that despite reduced AMPA-R expression, LGI1 IgG increased the global hyperexcitability in the hippocampal neuronal network. Decreased AMPA-R expression at inhibitory neurons and the lack of LGI1 IgG effect in presence of GABA antagonist on excitability, led us to conclude that LGI1 function might be essential for the proper functioning of the overall network and orchestrate the imbalance between inhibition and excitation. Our work suggests that LGI1 IgG reduced the inhibitory network activity more significantly than the excitatory network shedding lights on the essential role of the inhibitory network to trigger epileptic seizures in patients with LGI1 LE.
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12
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Haikazian S, Olson MF. MICAL1 Monooxygenase in Autosomal Dominant Lateral Temporal Epilepsy: Role in Cytoskeletal Regulation and Relation to Cancer. Genes (Basel) 2022; 13:715. [PMID: 35627100 PMCID: PMC9141472 DOI: 10.3390/genes13050715] [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: 03/18/2022] [Revised: 04/11/2022] [Accepted: 04/14/2022] [Indexed: 12/04/2022] Open
Abstract
Autosomal dominant lateral temporal epilepsy (ADLTE) is a genetic focal epilepsy associated with mutations in the LGI1, RELN, and MICAL1 genes. A previous study linking ADLTE with two MICAL1 mutations that resulted in the substitution of a highly conserved glycine residue for serine (G150S) or a frameshift mutation that swapped the last three C-terminal amino acids for 59 extra residues (A1065fs) concluded that the mutations increased enzymatic activity and promoted cell contraction. The roles of the Molecule Interacting with CasL 1 (MICAL1) protein in tightly regulated semaphorin signaling pathways suggest that activating MICAL1 mutations could result in defects in axonal guidance during neuronal development. Further studies would help to illuminate the causal relationships of these point mutations with ADLTE. In this review, we discuss the proposed pathogenesis caused by mutations in these three genes, with a particular emphasis on the G150S point mutation discovered in MICAL1. We also consider whether these types of activating MICAL1 mutations could be linked to cancer.
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Affiliation(s)
| | - Michael F. Olson
- Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3, Canada;
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13
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Teng X, Hu P, Chen Y, Zang Y, Ye X, Ou J, Chen G, Shi YS. A novel
Lgi1
mutation causes white matter abnormalities and impairs motor coordination in mice. FASEB J 2022; 36:e22212. [DOI: 10.1096/fj.202101652r] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/18/2022] [Accepted: 02/03/2022] [Indexed: 12/22/2022]
Affiliation(s)
- Xiao‐Yu Teng
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Ping Hu
- Department of Prenatal Diagnosis State Key Laboratory of Reproductive Medicine Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital Nanjing China
| | - Yangyang Chen
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Yanyu Zang
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Xiaolian Ye
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Jingmin Ou
- Department of General Surgery Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine Shanghai China
| | - Guiquan Chen
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Yun Stone Shi
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
- State Key Laboratory of Pharmaceutical Biotechnology Department of Neurology Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing University Nanjing China
- Institute for Brain Sciences Nanjing University Nanjing China
- Chemistry and Biomedicine Innovation Center Nanjing University Nanjing China
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14
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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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15
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Hu P, Wu D, Zang YY, Wang Y, Zhou YP, Qiao F, Teng XY, Chen J, Li QQ, Sun JH, Liu T, Feng HY, Zhou QG, Shi YS, Xu Z. A novel LGI1 mutation causing autosomal dominant lateral temporal lobe epilepsy confirmed by a precise knock-in mouse model. CNS Neurosci Ther 2021; 28:237-246. [PMID: 34767694 PMCID: PMC8739050 DOI: 10.1111/cns.13761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 10/20/2021] [Accepted: 10/25/2021] [Indexed: 12/30/2022] Open
Abstract
AIMS This study aimed to explore the pathomechanism of a mutation on the leucine-rich glioma inactivated 1 gene (LGI1) identified in a family having autosomal dominant lateral temporal lobe epilepsy (ADLTE), using a precise knock-in mouse model. METHODS AND RESULTS A novel LGI1 mutation, c.152A>G; p. Asp51Gly, was identified by whole exome sequencing in a Chinese family with ADLTE. The pathomechanism of the mutation was explored by generating Lgi1D51G knock-in mice that precisely phenocopied the epileptic symptoms of human patients. The Lgi1D51G / D51G mice showed spontaneous recurrent generalized seizures and premature death. The Lgi1D51G /+ mice had partial epilepsy, with half of them displaying epileptiform discharges on electroencephalography. They also showed enhanced sensitivity to the convulsant agent pentylenetetrazole. Mechanistically, the secretion of Lgi1 was impaired in the brain of the D51G knock-in mice and the protein level was drastically reduced. Moreover, the antiepileptic drugs, carbamazepine, oxcarbazepine, and sodium valproate, could prolong the survival time of Lgi1D51G / D51G mice, and oxcarbazepine appeared to be the most effective. CONCLUSIONS We identified a novel epilepsy-causing mutation of LGI1 in humans. The Lgi1D51G /+ mouse model, precisely phenocopying epileptic symptoms of human patients, could be a useful tool in future studies on the pathogenesis and potential therapies for epilepsy.
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Affiliation(s)
- Ping Hu
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Dan Wu
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Yan-Yu Zang
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Yan Wang
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Ya-Ping Zhou
- School of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Fengchang Qiao
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Xiao-Yu Teng
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Jiang Chen
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Qing-Qing Li
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Jia-Hui Sun
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - TingTing Liu
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Hao-Yang Feng
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Qi-Gang Zhou
- School of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Yun Stone Shi
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China.,Chemistry and Biomedicine Innovation Center, Nanjing University, Nanjing, China.,Institute for Brain Sciences, Nanjing University, Nanjing, China
| | - Zhengfeng Xu
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
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16
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Fels E, Muñiz-Castrillo S, Vogrig A, Joubert B, Honnorat J, Pascual O. Role of LGI1 protein in synaptic transmission: From physiology to pathology. Neurobiol Dis 2021; 160:105537. [PMID: 34695575 DOI: 10.1016/j.nbd.2021.105537] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/20/2021] [Accepted: 10/21/2021] [Indexed: 01/17/2023] Open
Abstract
Leucine-Rich Glioma Inactivated protein 1 (LGI1) is a secreted neuronal protein highly expressed in the central nervous system and high amount are found in the hippocampus. An alteration of its function has been described in few families of patients with autosomal dominant temporal lobe epilepsy (ADLTE) or with autoimmune limbic encephalitis (LE), both characterized by epileptic seizures. Studies have shown that LGI1 plays an essential role during development, but also in neuronal excitability through an action on voltage-gated potassium Kv1.1 channels, and in synaptic transmission by regulating the surface expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPA-R). Over the last decade, a growing number of studies investigating LGI1 functions have been published. They aimed to improve the understanding of LGI1 function in the regulation of neuronal networks using different animal and cellular models. LGI1 appears to be a major actor of synaptic regulation by modulating trans-synaptically pre- and post-synaptic proteins. In this review, we will focus on LGI1 binding partners, "A Disintegrin And Metalloprotease (ADAM) 22 and 23", the complex they form at the synapse, and will discuss the effects of LGI1 on neuronal excitability and synaptic transmission in physiological and pathological conditions. Finally, we will highlight new insights regarding N-terminal Leucine-Rich Repeat (LRR) domain and C-terminal Epitempin repeat (EPTP) domain and their potentially distinct role in LGI1 function.
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Affiliation(s)
- Elodie Fels
- Synaptopathies and Auto-antibodies (SynatAc) Team, Institut NeuroMyoGène, INSERM U1217/CNRS UMR 5310, Universités de Lyon, Université Claude Bernard Lyon 1, Lyon, France; Université Claude Bernard Lyon 1, Universités de Lyon, Lyon, France
| | - Sergio Muñiz-Castrillo
- Synaptopathies and Auto-antibodies (SynatAc) Team, Institut NeuroMyoGène, INSERM U1217/CNRS UMR 5310, Universités de Lyon, Université Claude Bernard Lyon 1, Lyon, France; Université Claude Bernard Lyon 1, Universités de Lyon, Lyon, France; French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique, 59 Boulevard Pinel, 69677 Bron Cedex, France
| | - Alberto Vogrig
- Synaptopathies and Auto-antibodies (SynatAc) Team, Institut NeuroMyoGène, INSERM U1217/CNRS UMR 5310, Universités de Lyon, Université Claude Bernard Lyon 1, Lyon, France; Université Claude Bernard Lyon 1, Universités de Lyon, Lyon, France; French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique, 59 Boulevard Pinel, 69677 Bron Cedex, France
| | - Bastien Joubert
- Université Claude Bernard Lyon 1, Universités de Lyon, Lyon, France; French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique, 59 Boulevard Pinel, 69677 Bron Cedex, France
| | - Jérôme Honnorat
- Synaptopathies and Auto-antibodies (SynatAc) Team, Institut NeuroMyoGène, INSERM U1217/CNRS UMR 5310, Universités de Lyon, Université Claude Bernard Lyon 1, Lyon, France; Université Claude Bernard Lyon 1, Universités de Lyon, Lyon, France; French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique, 59 Boulevard Pinel, 69677 Bron Cedex, France.
| | - Olivier Pascual
- Synaptopathies and Auto-antibodies (SynatAc) Team, Institut NeuroMyoGène, INSERM U1217/CNRS UMR 5310, Universités de Lyon, Université Claude Bernard Lyon 1, Lyon, France; Université Claude Bernard Lyon 1, Universités de Lyon, Lyon, France.
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17
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Fukata Y, Hirano Y, Miyazaki Y, Yokoi N, Fukata M. Trans-synaptic LGI1–ADAM22–MAGUK in AMPA and NMDA receptor regulation. Neuropharmacology 2021; 194:108628. [DOI: 10.1016/j.neuropharm.2021.108628] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 02/06/2023]
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18
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Perveen N, Ashraf W, Alqahtani F, Fawad Rasool M, Samad N, Imran I. Temporal Lobe Epilepsy: What do we understand about protein alterations? Chem Biol Drug Des 2021; 98:377-394. [PMID: 34132061 DOI: 10.1111/cbdd.13858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/22/2021] [Accepted: 04/18/2021] [Indexed: 01/19/2023]
Abstract
During neuronal diseases, neuronal proteins get disturbed due to changes in the connections of neurons. As a result, neuronal proteins get disturbed and cause epilepsy. At the genetic level, many mutations may take place in proteins like axon guidance proteins, leucine-rich glioma inactivated 1 protein, microtubular protein, pore-forming, chromatin remodeling, and chemokine proteins which may lead toward temporal lobe epilepsy. These proteins can be targeted in the future for the treatment purpose of epilepsy. Novel avenues can be developed for therapeutic interventions by these new insights.
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Affiliation(s)
- Nadia Perveen
- Department of Pharmacology, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Waseem Ashraf
- Department of Pharmacology, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Faleh Alqahtani
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Muhammad Fawad Rasool
- Department of Pharmacy Practice, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Noreen Samad
- Department of Biochemistry, Faculty of Science, Bahauddin Zakariya University, Multan, Pakistan
| | - Imran Imran
- Department of Pharmacology, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
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LOTUS, an endogenous Nogo receptor antagonist, is involved in synapse and memory formation. Sci Rep 2021; 11:5085. [PMID: 33658590 PMCID: PMC7930056 DOI: 10.1038/s41598-021-84106-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 02/12/2021] [Indexed: 11/29/2022] Open
Abstract
The Nogo signal is involved in impairment of memory formation. We previously reported the lateral olfactory tract usher substance (LOTUS) as an endogenous antagonist of the Nogo receptor 1 that mediates the inhibition of axon growth and synapse formation. Moreover, we found that LOTUS plays an essential role in neural circuit formation and nerve regeneration. However, the effects of LOTUS on synapse formation and memory function have not been elucidated. Here, we clearly showed the involvement of LOTUS in synapse formation and memory function. The cultured hippocampal neurons derived from lotus gene knockout (LOTUS-KO) mice exhibited a decrease in synaptic density compared with those from wild-type mice. We also found decrease of dendritic spine formation in the adult hippocampus of LOTUS-KO mice. Finally, we demonstrated that LOTUS deficiency impairs memory formation in the social recognition test and the Morris water maze test, indicating that LOTUS is involved in functions of social and spatial learning and memory. These findings suggest that LOTUS affects synapse formation and memory function.
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Gawel K, Langlois M, Martins T, van der Ent W, Tiraboschi E, Jacmin M, Crawford AD, Esguerra CV. Seizing the moment: Zebrafish epilepsy models. Neurosci Biobehav Rev 2020; 116:1-20. [PMID: 32544542 DOI: 10.1016/j.neubiorev.2020.06.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/20/2020] [Accepted: 06/05/2020] [Indexed: 12/14/2022]
Abstract
Zebrafish are now widely accepted as a valuable animal model for a number of different central nervous system (CNS) diseases. They are suitable both for elucidating the origin of these disorders and the sequence of events culminating in their onset, and for use as a high-throughput in vivo drug screening platform. The availability of powerful and effective techniques for genome manipulation allows the rapid modelling of different genetic epilepsies and of conditions with seizures as a core symptom. With this review, we seek to summarize the current knowledge about existing epilepsy/seizures models in zebrafish (both pharmacological and genetic) and compare them with equivalent rodent and human studies. New findings obtained from the zebrafish models are highlighted. We believe that this comprehensive review will highlight the value of zebrafish as a model for investigating different aspects of epilepsy and will help researchers to use these models to their full extent.
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Affiliation(s)
- Kinga Gawel
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway; Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | | | - Teresa Martins
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg
| | - Wietske van der Ent
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Ettore Tiraboschi
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway; Neurophysics Group, Center for Mind/Brain Sciences, University of Trento, Piazza Manifattura 1, Building 14, 38068, Rovereto, TN, Italy
| | - Maxime Jacmin
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg
| | - Alexander D Crawford
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg; Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | - Camila V Esguerra
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway.
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Yamagata A, Fukai S. Insights into the mechanisms of epilepsy from structural biology of LGI1-ADAM22. Cell Mol Life Sci 2020; 77:267-274. [PMID: 31432233 PMCID: PMC11104983 DOI: 10.1007/s00018-019-03269-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/05/2019] [Accepted: 08/09/2019] [Indexed: 01/05/2023]
Abstract
Epilepsy is one of the most common brain disorders, which can be caused by abnormal synaptic transmissions. Many epilepsy-related mutations have been identified in synaptic ion channels, which are main targets for current antiepileptic drugs. One of the novel potential targets for therapy of epilepsy is a class of non-ion channel-type epilepsy-related proteins. The leucine-rich repeat glioma-inactivated protein 1 (LGI1) is a neuronal secreted protein, and has been extensively studied as a product of a causative gene for autosomal dominant lateral temporal lobe epilepsy (ADLTE; also known as autosomal dominant partial epilepsy with auditory features [ADPEAF]). At least 43 mutations of LGI1 have been found in ADLTE families. Additionally, autoantibodies against LGI1 in limbic encephalitis are associated with amnesia, seizures, and cognitive dysfunction. Although the relationship of LGI1 with synaptic transmission and synaptic disorders has been studied genetically, biochemically, and clinically, the structural mechanism of LGI1 remained largely unknown until recently. In this review, we introduce insights into pathogenic mechanisms of LGI1 from recent structural studies on LGI1 and its receptor, ADAM22. We also discuss the mechanism for pathogenesis of autoantibodies against LGI1, and the potential of chemical correctors as novel drugs for epilepsy, with structural aspects of LGI1-ADAM22.
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Affiliation(s)
- Atsushi Yamagata
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan.
- Synchrotron Radiation Research Organization, The University of Tokyo, Tokyo, 113-0032, Japan.
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, 277-8561, Japan.
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Kanagawa, 230-0045, Japan.
| | - Shuya Fukai
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan.
- Synchrotron Radiation Research Organization, The University of Tokyo, Tokyo, 113-0032, Japan.
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, 277-8561, Japan.
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22
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Liu F, Du C, Tian X, Ma Y, Zhao B, Yan Y, Lin Z, Lin P, Zhou R, Wang X. A novel LGI1 missense mutation causes dysfunction in cortical neuronal migration and seizures. Brain Res 2019; 1721:146332. [PMID: 31301272 DOI: 10.1016/j.brainres.2019.146332] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/23/2019] [Accepted: 07/09/2019] [Indexed: 01/17/2023]
Abstract
BACKGROUND To explore the causative genes and pathogenesis of autosomal dominant partial epilepsy with auditory features in a large Chinese family that includes 7 patients over four generations. METHODS We used targeted exome sequencing and Sanger sequencing to validate the mutation. Zebrafish were used to explore the epileptic behavior caused by the mutation. Primary cortical neuronal culturing and in utero electroporation were used to observe the influences of the mutation on neuronal polarity and migration. RESULTS We report the identification of a novel missense mutation, c.128C > G (p. Pro43Arg), in exon 1 of LGI1. The heterozygous missense mutation, which cosegregated with the syndrome, was absent in 300 unrelated and matched-ancestor controls. The mutation inhibited the secretion of LGI1 and could not rescue the hyperactivity caused by lgi1a knockdown in zebrafish. In vitro, mutant LGI1 interrupts normal cell polarity. In agreement with these findings, dysfunctional cortical neuron migration was observed using in utero electroporation technology, which is reminiscent of the subtle structural changes in the lateral temporal region observed in the proband of this family. CONCLUSION Our findings enrich the spectrum of LGI1 mutations and support the pathogenicity of the mutation. Furthermore, additional information regarding the role of LGI1 in the development of temporal lobe epilepsy was elucidated, and a potential relationship was established between cortical neuronal migration dysfunction and autosomal dominant partial epilepsy with auditory features.
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Affiliation(s)
- Feng Liu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Chao Du
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Xin Tian
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Yuanlin Ma
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Bei Zhao
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Yin Yan
- Department of Neurology, The Ninth People's Hospital of Chongqing, Chongqing 400016, China
| | - Zijun Lin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Peijia Lin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Ruijiao Zhou
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China
| | - Xuefeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing 400016, China.
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Inactivation of Lgi1 in murine neuronal precursor cells leads to dysregulation of axon guidance pathways. Genomics 2019; 112:1167-1172. [PMID: 31276752 DOI: 10.1016/j.ygeno.2019.07.001] [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: 01/09/2019] [Revised: 05/22/2019] [Accepted: 07/01/2019] [Indexed: 11/20/2022]
Abstract
LGI1 mutations predispose to a rare epilepsy syndrome and when inactivated in mice leads to early onset seizures and premature death. Histopathology of the mature brain soon after birth shows cortical dysplasia in Lgi1 null mice with hypercellularity in the outer cortical layers. Here we show extensive gene expression changes in neuronal precursor cells from Lgi1 null mice compared with wild type mice. The most significantly dysregulated pathway involves canonical axon guidance signaling with multiple networks involved in cell movement, adhesion and invasion related to actin cytoskeleton reorganization. The Lgi1 null NPCs show increased cell motility in vitro compared with normal counterparts. Dysregulation of genes critical to cell movement/migration and critical transcription factors involved in early neuronal development is a prominent feature. These studies provide a critical mechanistic link to the observation of increased cellularity in the outer layers of the developing cortex in Lgi1 null mice.
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24
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Contreras A, Hines DJ, Hines RM. Molecular Specialization of GABAergic Synapses on the Soma and Axon in Cortical and Hippocampal Circuit Function and Dysfunction. Front Mol Neurosci 2019; 12:154. [PMID: 31297048 PMCID: PMC6607995 DOI: 10.3389/fnmol.2019.00154] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 05/31/2019] [Indexed: 12/24/2022] Open
Abstract
The diversity of inhibitory interneurons allows for the coordination and modulation of excitatory principal cell firing. Interneurons that release GABA (γ-aminobutyric acid) onto the soma and axon exert powerful control by virtue of proximity to the site of action potential generation at the axon initial segment (AIS). Here, we review and examine the cellular and molecular regulation of soma and axon targeting GABAergic synapses in the cortex and hippocampus. We also describe their role in controlling network activity in normal and pathological states. Recent studies have demonstrated a specific role for postsynaptic dystroglycan in the formation and maintenance of cholecystokinin positive basket cell terminals contacting the soma, and postsynaptic collybistin in parvalbumin positive chandelier cell contacts onto the AIS. Unique presynaptic molecular contributors, LGI2 and FGF13, expressed in parvalbumin positive basket cells and chandelier cells, respectively, have also recently been identified. Mutations in the genes encoding proteins critical for somatic and AIS inhibitory synapses have been associated with human disorders of the nervous system. Dystroglycan dysfunction in some congenital muscular dystrophies is associated with developmental brain malformations, intellectual disability, and rare epilepsy. Collybistin dysfunction has been linked to hyperekplexia, epilepsy, intellectual disability, and developmental disorders. Both LGI2 and FGF13 mutations are implicated in syndromes with epilepsy as a component. Advancing our understanding of the powerful roles of somatic and axonic GABAergic contacts in controlling activity patterns in the cortex and hippocampus will provide insight into the pathogenesis of epilepsy and other nervous system disorders.
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Affiliation(s)
- April Contreras
- Department of Psychology, University of Nevada, Las Vegas, Las Vegas, NV, United States
| | - Dustin J Hines
- Department of Psychology, University of Nevada, Las Vegas, Las Vegas, NV, United States
| | - Rochelle M Hines
- Department of Psychology, University of Nevada, Las Vegas, Las Vegas, NV, United States
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25
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Silva J, Qin H, Cowell JK. Selective inactivation of LGI1 in neuronal precursor cells leads to cortical dysplasia in mice. Genesis 2018; 57:e23268. [DOI: 10.1002/dvg.23268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/30/2018] [Accepted: 11/26/2018] [Indexed: 01/23/2023]
Affiliation(s)
- Jeane Silva
- Department of Pathology, Georgia Cancer Center; Augusta University; Augusta Georgia
| | - Haiyan Qin
- Department of Pathology, Georgia Cancer Center; Augusta University; Augusta Georgia
| | - John K Cowell
- Department of Pathology, Georgia Cancer Center; Augusta University; Augusta Georgia
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26
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The Nogo Receptor Ligand LGI1 Regulates Synapse Number and Synaptic Activity in Hippocampal and Cortical Neurons. eNeuro 2018; 5:eN-NWR-0185-18. [PMID: 30225353 PMCID: PMC6140115 DOI: 10.1523/eneuro.0185-18.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/31/2018] [Accepted: 08/14/2018] [Indexed: 12/20/2022] Open
Abstract
Leucine-rich glioma-inactivated protein 1 (LGI1) is a secreted neuronal protein and a Nogo receptor 1 (NgR1) ligand. Mutations in LGI1 in humans causes autosomal dominant lateral temporal lobe epilepsy and homozygous deletion of LGI1 in mice results in severe epileptic seizures that cause early postnatal death. NgR1 plays an important role in the development of CNS synapses and circuitry by limiting plasticity in the adult cortex via the activation of RhoA. These relationships and functions prompted us to examine the effect of LGI1 on synapse formation in vitro and in vivo. We report that application of LGI1 increases synaptic density in neuronal culture and that LGI1 null hippocampus has fewer dendritic mushroom spines than in wild-type (WT) littermates. Further, our electrophysiological investigations demonstrate that LGI1 null hippocampal neurons possess fewer and weaker synapses. RhoA activity is significantly increased in cortical cultures derived from LGI1 null mice and using a reconstituted system; we show directly that LGI1 antagonizes NgR1-tumor necrosis factor receptor orphan Y (TROY) signaling. Our data suggests that LGI1 enhances synapse formation in cortical and hippocampal neurons by reducing NgR1 signaling.
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27
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Xie YJ, Zhou L, Wang Y, Jiang NW, Cao S, Shao CY, Wang XT, Li XY, Shen Y, Zhou L. Leucine-Rich Glioma Inactivated 1 Promotes Oligodendrocyte Differentiation and Myelination via TSC-mTOR Signaling. Front Mol Neurosci 2018; 11:231. [PMID: 30034322 PMCID: PMC6043672 DOI: 10.3389/fnmol.2018.00231] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/12/2018] [Indexed: 12/26/2022] Open
Abstract
Leucine-rich glioma inactivated 1 (Lgi1), a putative tumor suppressor, is tightly associated with autosomal dominant lateral temporal lobe epilepsy (ADLTE). It has been shown that Lgi1 regulates the myelination of Schwann cells in the peripheral nervous system (PNS). However, the function and underlying mechanisms for Lgi1 regulation of oligodendrocyte differentiation and myelination in the central nervous system (CNS) remain elusive. In addition, whether Lgi1 is required for myelin maintenance is unknown. Here, we show that Lgi1 is necessary and sufficient for the differentiation of oligodendrocyte precursor cells and is also required for the maintenance of myelinated fibers. The hypomyelination in Lgi1-/- mice attributes to the inhibition of the biosynthesis of lipids and proteins in oligodendrocytes (OLs). Moreover, we found that Lgi1 deficiency leads to a decrease in expression of tuberous sclerosis complex 1 (TSC1) and activates mammalian target of rapamycin signaling. Together, the present work establishes that Lgi1 is a regulator of oligodendrocyte development and myelination in CNS.
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Affiliation(s)
- Ya-Jun Xie
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Lin Zhou
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Yin Wang
- Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical UniversityYinchuan, China
| | - Nan-Wei Jiang
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of MedicineNingbo, China
| | - Shenglong Cao
- Department of Neurosurgery, Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou, China
| | - Chong-Yu Shao
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Xin-Tai Wang
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Xiang-Yao Li
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Ying Shen
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Liang Zhou
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
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Dazzo E, Pasini E, Furlan S, de Biase D, Martinoni M, Michelucci R, Nobile C. LGI1 tumor tissue expression and serum autoantibodies in patients with primary malignant glioma. Clin Neurol Neurosurg 2018; 170:27-33. [PMID: 29723732 DOI: 10.1016/j.clineuro.2018.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/26/2018] [Accepted: 04/02/2018] [Indexed: 02/05/2023]
Abstract
OBJECTIVES The Leucine-rich glioma inactivated 1 (LGI1) protein is thought to be implicated in malignant progression of glioma tumors, and mutations in the encoding gene, LGI1, cause autosomal dominant lateral temporal epilepsy, a genetic focal epilepsy syndrome. The aim of this study was to investigate the possible involvement of LGI1 in high-grade glioma-associated epilepsy by analyzing its expression in tumor specimens of patients with and without epilepsy and by searching for LGI1 autoantibodies in the sera these patients. PATIENTS AND METHODS We examined tumor tissue samples from 24 patients with high-grade gliomas (12 with and 12 without epilepsy) by immunoblot and detected variable amounts of LGI1 in tumor tissues from 9/24 (37%) patients. RESULTS LGI1 was detected in 7/12 (58%) patients with epilepsy and in 2/12 (16%) patients without epilepsy (p = 0.0894; Fisher's exact test). Moreover, testing blood sera of five patients for antibodies against LGI1 revealed LGI1 autoantibodies in two patients, both suffering from epilepsy and expressing LGI1 in tumor tissue. CONCLUSION Our findings suggest that there may be a preferential expression of LGI1 in high-grade glioma tumors of patients with epilepsy. We also unveil the presence of serum LGI1 autoantibodies in some patients with high-grade gliomas, where they might play an epileptogenic role.
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Affiliation(s)
- Emanuela Dazzo
- CNR-Neuroscience Institute, Section of Padua, Viale G. Colombo 3, 35121 Padova, Italy.
| | - Elena Pasini
- IRCCS-Institute of Neurological Sciences, Unit of Neurology, Bellaria Hospital, Bologna, Italy.
| | - Sandra Furlan
- CNR-Neuroscience Institute, Section of Padua, Viale G. Colombo 3, 35121 Padova, Italy.
| | - Dario de Biase
- Department of Pharmacology and Biotechnology (FaBiT), University of Bologna, Bologna, Italy.
| | - Matteo Martinoni
- IRCCS-Institute of Neurological Sciences, Unit of Neurosurgery, Bellaria Hospital, Bologna, Italy.
| | - Roberto Michelucci
- IRCCS-Institute of Neurological Sciences, Unit of Neurology, Bellaria Hospital, Bologna, Italy.
| | - Carlo Nobile
- CNR-Neuroscience Institute, Section of Padua, Viale G. Colombo 3, 35121 Padova, Italy; Department of Biomedical Sciences, University of Padua, Padova, Italy.
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Zhou L, Zhou L, Su LD, Cao SL, Xie YJ, Wang N, Shao CY, Wang YN, Zhou JH, Cowell JK, Shen Y. Celecoxib Ameliorates Seizure Susceptibility in Autosomal Dominant Lateral Temporal Epilepsy. J Neurosci 2018; 38:3346-3357. [PMID: 29491011 PMCID: PMC5884462 DOI: 10.1523/jneurosci.3245-17.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/24/2018] [Accepted: 02/20/2018] [Indexed: 12/11/2022] Open
Abstract
Autosomal dominant lateral temporal epilepsy (ADLTE) is an inherited syndrome caused by mutations in the leucine-rich glioma inactivated 1 (LGI1) gene. It is known that glutamatergic transmission is altered in LGI1 mutant mice, and seizures can be reduced by restoring LGI1 function. Yet, the mechanism underlying ADLTE is unclear. Here, we propose that seizures in male LGI1-/- mice are due to nonsynaptic epileptiform activity in cortical neurons. We examined the intrinsic excitability of pyramidal neurons in the temporal cortex of male LGI1-/- mice and found that the voltage-gated K+ channel Kv1.2 was significantly downregulated. We also found that cytosolic phospholipase A2 (cPLA2)-cyclooxygenase 2 (Cox2) signaling was enhanced in LGI1-/- mice. Interestingly, Cox2 inhibition effectively restored the dysregulated Kv1.2 and reduced the intrinsic excitability of pyramidal neurons. Moreover, in vivo injection of celecoxib, an FDA-approved nonsteroidal anti-inflammatory drug, rescued the defective Kv1.2 (an ∼1.9-fold increase), thereby alleviating the seizure susceptibility and extending the life of LGI1-/- mice by 5 d. In summary, we conclude that LGI1 deficiency dysregulates cPLA2-Cox2 signaling to cause hyperexcitability of cortical pyramidal neurons, and celecoxib is a potential agent to manage human ADLTE.SIGNIFICANCE STATEMENT Haploinsufficiency of the leucine-rich glioma inactivated 1 (LGI1) gene is the major pathogenic basis for ADLTE, an inherited syndrome with no cure to date. Existing studies suggest that altered glutamatergic transmission in the hippocampus causes this disease, but the data are paradoxical. We demonstrate that the loss of LGI1 decreases Kv1.2 expression, enhances intrinsic excitability, and thereby causes epilepsy. Interestingly, for the first time, we show that an FDA-approved drug, celecoxib, rescues the Kv1.2 defect and alleviates seizure susceptibility in LGI1-/- mice, as well as improving their survival. Thus, we suggest that celecoxib is a promising drug for the treatment of ADLTE patients.
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Affiliation(s)
- Lin Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Liang Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | | | - Sheng-Long Cao
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
- Department of Neurosurgery, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Ya-Jun Xie
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Na Wang
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
- School of Medicine, Zhejiang University City College, Hangzhou 310015, China, and
| | - Chong-Yu Shao
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Ya-Nan Wang
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jia-Huan Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - John K Cowell
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
- GRU Cancer Center, Augusta University, Augusta, Georgia 30912
| | - Ying Shen
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China,
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30
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Dazzo E, Rehberg K, Michelucci R, Passarelli D, Boniver C, Vianello Dri V, Striano P, Striano S, Pasterkamp RJ, Nobile C. Mutations in MICAL-1cause autosomal-dominant lateral temporal epilepsy. Ann Neurol 2018; 83:483-493. [PMID: 29394500 DOI: 10.1002/ana.25167] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 01/30/2018] [Accepted: 01/31/2018] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Autosomal-dominant lateral temporal epilepsy (ADLTE) is a genetic focal epilepsy characterized by auditory symptoms. Two genes, LGI1 and RELN, encoding secreted proteins, are implicated in the etiology of ADLTE, but half of the affected families remain genetically unsolved, and the underlying molecular mechanisms are yet to be clarified. We aimed to identify additional genes causing ADLTE to better understand the genetic basis and molecular pathway underlying this epileptic disorder. METHODS A cohort of Italian ADLTE families was examined by whole exome sequencing combined with genome-wide single-nucleotide polymorphism-array linkage analysis. RESULTS We identified two ADLTE-causing variants in the MICAL-1 gene: a p.Gly150Ser substitution occurring in the enzymatically active monooxygenase (MO) domain and a p.Ala1065fs frameshift indel in the C-terminal domain, which inhibits the oxidoreductase activity of the MO domain. Each variant segregated with ADLTE in a single family. Examination of candidate variants in additional genes excluded their implication in ADLTE. In cell-based assays, both variants significantly increased MICAL-1 oxidoreductase activity and induced cell contraction in COS7 cells, which likely resulted from deregulation of F-actin dynamics. INTERPRETATION MICAL-1 oxidoreductase activity induces disassembly of actin filaments, thereby regulating the organization of the actin cytoskeleton in developing and adult neurons and in other cell types. This suggests that dysregulation of the actin cytoskeleton dynamics is a likely mechanism by which MICAL-1 pathogenic variants lead to ADLTE. Ann Neurol 2018;83:483-493.
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Affiliation(s)
- Emanuela Dazzo
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy
| | - Kati Rehberg
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Roberto Michelucci
- IRCCS-Institute of Neurological Sciences of Bologna, Unit of Neurology, Bellaria Hospital, Bologna, Italy
| | | | - Clementina Boniver
- Clinical Neurophysiology, Department of Pediatrics, University of Padua, Padova, Italy
| | - Valeria Vianello Dri
- APSS Trento, Mental Health Department, Child and Adolescent Neuropsichiatry 1, Trento, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, "G. Gaslini" Institute, Genova, Italy
| | - Salvatore Striano
- Department of Neurological Sciences, Federico II University, Napoli, Italy
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Carlo Nobile
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy.,Department of Biomedical Sciences, University of Padua, Padova, Italy
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Kim SY, Um YH, Lim SC, Jeong JH. Limbic Encephalitis Manifesting as Selective Amnesia and Seizure-like Activity: A Case Report. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE : THE OFFICIAL SCIENTIFIC JOURNAL OF THE KOREAN COLLEGE OF NEUROPSYCHOPHARMACOLOGY 2018; 16:109-113. [PMID: 29397673 PMCID: PMC5810455 DOI: 10.9758/cpn.2018.16.1.109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/18/2016] [Accepted: 07/26/2016] [Indexed: 12/29/2022]
Abstract
Limbic encephalitis (LE) is characterized by short-term memory loss, disorientation, agitation, seizures, and histopathological evidence of medial temporal lobe inflammation. Leucine-rich, glioma inactivated 1 (LGI-1) is an auto-antigen associated with LE. We report a 37-year-old male patient with LGI-1-related LE who presented with recurrent episodes of selective amnesia, seizure-like activity, confusion, and personality change. His symptoms were significantly improved with steroid therapy. Thorough differential diagnosis with consideration for autoimmune encephalitis should be in patients with presentation of symptoms, such as memory impairment, personality change and seizure-like activity, especially when other neurological diagnoses are excluded.
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Affiliation(s)
- So-Yeon Kim
- Department of Psychiatry, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Yoo Hyun Um
- Department of Psychiatry, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Sung Chul Lim
- Department of Neurology, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jong-Hyun Jeong
- Department of Psychiatry, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Dupont S. Epilessie focali strutturali metaboliche o epilessie focali con eziologia identificata. Neurologia 2017. [DOI: 10.1016/s1634-7072(17)85554-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Karlsson TE, Wellfelt K, Olson L. Spatiotemporal and Long Lasting Modulation of 11 Key Nogo Signaling Genes in Response to Strong Neuroexcitation. Front Mol Neurosci 2017; 10:94. [PMID: 28442990 PMCID: PMC5386981 DOI: 10.3389/fnmol.2017.00094] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/20/2017] [Indexed: 12/13/2022] Open
Abstract
Inhibition of nerve growth and plasticity in the CNS is to a large part mediated by Nogo-like signaling, now encompassing a plethora of ligands, receptors, co-receptors and modulators. Here we describe the distribution and levels of mRNA encoding 11 key genes involved in Nogo-like signaling (Nogo-A, Oligodendrocyte-Myelin glycoprotein (OMgp), Nogo receptor 1 (NgR1), NgR2, NgR3, Lingo-1, TNF receptor orphan Y (Troy), Olfactomedin, Lateral olfactory tract usher substance (Lotus) and membrane-type matrix metalloproteinase-3 (MT3-MPP)), as well as BDNF and GAPDH. Expression was analyzed in nine different brain areas before, and at eight time points during the first 3 days after a strong neuroexcitatory stimulation, caused by one kainic acid injection. A temporo-spatial pattern of orderly transcriptional regulations emerges that strengthens the role of Nogo-signaling mechanisms for synaptic plasticity in synchrony with transcriptional increases of BDNF mRNA. For most Nogo-type signaling genes, the largest alterations of mRNA levels occur in the dentate gyrus, with marked alterations also in the CA1 region. Changes occurred somewhat later in several areas of the cerebral cortex. The detailed spatio-temporal pattern of mRNA presence and kainic acid-induced transcriptional response is gene-specific. We reveal that several different gene alterations combine to decrease (and later increase) Nogo-like signaling, as expected to allow structural plasticity responses. Other genes are altered in the opposite direction, suggesting that the system prepares in advance in order to rapidly restore balance. However, the fact that Lingo-1 shows a seemingly opposite, plasticity inhibiting response to kainic acid (strong increase of mRNA in the dentate gyrus), may instead suggest a plasticity-enhancing intracellular function of this presumed NgR1 co-receptor.
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Affiliation(s)
| | - Katrin Wellfelt
- Department of Neuroscience, Karolinska InstitutetStockholm, Sweden
| | - Lars Olson
- Department of Neuroscience, Karolinska InstitutetStockholm, Sweden
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Fukata Y, Yokoi N, Miyazaki Y, Fukata M. The LGI1–ADAM22 protein complex in synaptic transmission and synaptic disorders. Neurosci Res 2017; 116:39-45. [DOI: 10.1016/j.neures.2016.09.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 09/18/2016] [Accepted: 09/22/2016] [Indexed: 12/21/2022]
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Bost C, Pascual O, Honnorat J. Autoimmune encephalitis in psychiatric institutions: current perspectives. Neuropsychiatr Dis Treat 2016; 12:2775-2787. [PMID: 27822050 PMCID: PMC5089825 DOI: 10.2147/ndt.s82380] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Autoimmune encephalitis is a rare and newly described group of diseases involving autoantibodies directed against synaptic and neuronal cell surface antigens. It comprises a wide range of neuropsychiatric symptoms. Sensitive and specific diagnostic tests such as cell-based assay are primordial for the detection of neuronal cell surface antibodies in patients' cerebrospinal fluid or serum and determine the treatment and follow-up of the patients. As neurological symptoms are fairly well described in the literature, this review focuses on the nature of psychiatric symptoms occurring at the onset or during the course of the diseases. In order to help the diagnosis, the main neurological symptoms of the most representative synaptic and neuronal cell surface autoantibodies were detailed. Finally, the exploration of these autoantibodies for almost a decade allowed us to present an overview of autoimmune encephalitis incidence in psychiatric disease and the general guidelines for the management of psychiatric manifestations. For the majority of autoimmune encephalitis, the prognosis depends on the rapidity of the detection, identification, and the management of the disease. Because the presence of pronounced psychiatric symptoms drives patients to psychiatric institutions and can hinder the diagnosis, the aim of this work is to provide clues to help earlier detection by physicians and thus provide better medical care to patients.
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Affiliation(s)
- Chloe Bost
- French Reference Center of Paraneoplastic Neurological Syndrome, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France
- Synatac Team, NeuroMyoGene Institut, INSERM U1217/CNRS UMR5310, Lyon, France
- University Claude Bernard Lyon 1, Lyon, France
| | - Olivier Pascual
- Synatac Team, NeuroMyoGene Institut, INSERM U1217/CNRS UMR5310, Lyon, France
- University Claude Bernard Lyon 1, Lyon, France
| | - Jérôme Honnorat
- French Reference Center of Paraneoplastic Neurological Syndrome, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France
- Synatac Team, NeuroMyoGene Institut, INSERM U1217/CNRS UMR5310, Lyon, France
- University Claude Bernard Lyon 1, Lyon, France
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Dazzo E, Leonardi E, Belluzzi E, Malacrida S, Vitiello L, Greggio E, Tosatto SCE, Nobile C. Secretion-Positive LGI1 Mutations Linked to Lateral Temporal Epilepsy Impair Binding to ADAM22 and ADAM23 Receptors. PLoS Genet 2016; 12:e1006376. [PMID: 27760137 PMCID: PMC5070869 DOI: 10.1371/journal.pgen.1006376] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 09/20/2016] [Indexed: 01/17/2023] Open
Abstract
Autosomal dominant lateral temporal epilepsy (ADTLE) is a focal epilepsy syndrome caused by mutations in the LGI1 gene, which encodes a secreted protein. Most ADLTE-causing mutations inhibit LGI1 protein secretion, and only a few secretion-positive missense mutations have been reported. Here we describe the effects of four disease-causing nonsynonymous LGI1 mutations, T380A, R407C, S473L, and R474Q, on protein secretion and extracellular interactions. Expression of LGI1 mutant proteins in cultured cells shows that these mutations do not inhibit protein secretion. This finding likely results from the lack of effects of these mutations on LGI1 protein folding, as suggested by 3D protein modelling. In addition, immunofluorescence and co-immunoprecipitation experiments reveal that all four mutations significantly impair interaction of LGI1 with the ADAM22 and ADAM23 receptors on the cell surface. These results support the existence of a second mechanism, alternative to inhibition of protein secretion, by which ADLTE-causing LGI1 mutations exert their loss-of-function effect extracellularly, and suggest that interactions of LGI1 with both ADAM22 and ADAM23 play an important role in the molecular mechanisms leading to ADLTE. Temporal lobe epilepsy is the most common form of focal epilepsy. It is frequently associated with structural brain abnormalities, but genetic forms caused by mutations in major genes have also been described. Autosomal dominant lateral temporal epilepsy (ADLTE) is a familial condition characterized by focal seizures with prominent auditory symptoms. ADLTE-causing mutations are found in the LGI1 gene in about 30% of affected families. LGI1 encodes a protein, LGI1, that is secreted by neurons. Most LGI1 mutations suppress protein secretion, thereby preventing protein function in the extracellular environment. In this paper, we examine the effects of four LGI1 mutations and show that they do not inhibit secretion of the LGI1 protein but impair its interaction with the neuronal receptors ADAM22 and ADAM23. In agreement with these findings, a three- dimensional model of the protein predicts that these mutations have no impact on LGI1 structure but instead may affect amino acids that are critical for interactions with ADAM receptors. Our results provide novel evidence for an extracellular mechanism through which mutant LGI1 proteins cause ADLTE and strengthen the importance of LGI1-ADAM22/23 protein complex in the mechanisms underlying ADLTE.
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Affiliation(s)
- Emanuela Dazzo
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy
| | - Emanuela Leonardi
- Department of Woman and Child’s Health, University of Padua, Padova, Italy
| | - Elisa Belluzzi
- Department of Biology, University of Padua, Padova, Italy
| | - Sandro Malacrida
- Department of Biomedical Sciences, University of Padua, Padova, Italy
| | | | - Elisa Greggio
- Department of Biology, University of Padua, Padova, Italy
| | - Silvio C. E. Tosatto
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy
- Department of Biomedical Sciences, University of Padua, Padova, Italy
| | - Carlo Nobile
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy
- Department of Biomedical Sciences, University of Padua, Padova, Italy
- * E-mail:
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Abstract
Autoantibodies targeting proteins at the neuromuscular junction are known to cause several distinct myasthenic syndromes. Recently, autoantibodies targeting neurotransmitter receptors and associated proteins have also emerged as a cause of severe, but potentially treatable, diseases of the CNS. Here, we review the clinical evidence as well as in vitro and in vivo experimental evidence that autoantibodies account for myasthenic syndromes and autoimmune disorders of the CNS by disrupting the functional or structural integrity of synapses. Studying neurological and psychiatric diseases of autoimmune origin may provide new insights into the cellular and circuit mechanisms underlying a broad range of CNS disorders.
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Affiliation(s)
- Sarah J Crisp
- UCL Institute of Neurology, University College London, Queen Square House, Queen Square, London WC1N 3BG, UK
| | - Dimitri M Kullmann
- UCL Institute of Neurology, University College London, Queen Square House, Queen Square, London WC1N 3BG, UK
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Level 6, West Wing, John Radcliffe Hospital, Oxford OX3 9DU, UK
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Screening LGI1 in a cohort of 26 lateral temporal lobe epilepsy patients with auditory aura from Turkey detects a novel de novo mutation. Epilepsy Res 2016; 120:73-8. [DOI: 10.1016/j.eplepsyres.2015.12.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 11/02/2015] [Accepted: 12/09/2015] [Indexed: 11/24/2022]
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39
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Boillot M, Baulac S. Genetic models of focal epilepsies. J Neurosci Methods 2016; 260:132-43. [DOI: 10.1016/j.jneumeth.2015.06.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 01/06/2023]
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Selective Loss of Presynaptic Potassium Channel Clusters at the Cerebellar Basket Cell Terminal Pinceau in Adam11 Mutants Reveals Their Role in Ephaptic Control of Purkinje Cell Firing. J Neurosci 2015; 35:11433-44. [PMID: 26269648 DOI: 10.1523/jneurosci.1346-15.2015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
UNLABELLED A specialized axonal ending, the basket cell "pinceau," encapsulates the Purkinje cell axon initial segment (AIS), exerting final inhibitory control over the integrated outflow of the cerebellar cortex. This nonconventional axo-axonic contact extends beyond the perisomatic chemical GABAergic synaptic boutons to the distal AIS, lacks both sodium channels and local exocytotic machinery, and yet contains a dense cluster of voltage-gated potassium channels whose functional contribution is unknown. Here, we show that ADAM11, a transmembrane noncatalytic disintegrin, is the first reported Kv1-interacting protein essential for localizing Kv1.1 and Kv1.2 subunit complexes to the distal terminal. Selective absence of these channels at the pinceau due to mutation of ADAM11 spares spontaneous GABA release from basket cells at the perisomatic synapse yet eliminates ultrarapid ephaptic inhibitory synchronization of Purkinje cell firing. Our findings identify a critical role for presynaptic K(+) channels at the pinceau in ephaptic control over the speed and stability of spike rate coding at the Purkinje cell AIS in mice. SIGNIFICANCE STATEMENT This study identifies ADAM11 as the first essential molecule for the proper localization of potassium ion channels at presynaptic nerve terminals, where they modulate excitability and the release of neural transmitters. Genetic truncation of the transmembrane disintegrin and metalloproteinase protein ADAM11 resulted in the absence of Kv1 channels that are normally densely clustered at the terminals of basket cell axons in the cerebellar cortex. These specialized terminals are responsible for the release of the neurotransmitter GABA onto Purkinje cells and also display electrical signaling. In the ADAM11 mutant, GABAergic release was not altered, but the ultrarapid electrical signal was absent, demonstrating that the dense presynaptic cluster of Kv1 ion channels at these terminals mediate electrical transmission. Therefore, ADAM11 plays a critical role at this central synapse.
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Koskinen LLE, Seppälä EH, Belanger JM, Arumilli M, Hakosalo O, Jokinen P, Nevalainen EM, Viitmaa R, Jokinen TS, Oberbauer AM, Lohi H. Identification of a common risk haplotype for canine idiopathic epilepsy in the ADAM23 gene. BMC Genomics 2015; 16:465. [PMID: 26084559 PMCID: PMC4470040 DOI: 10.1186/s12864-015-1651-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 05/20/2015] [Indexed: 12/17/2022] Open
Abstract
Background Idiopathic epilepsy is a common neurological disease in human and domestic dogs but relatively few risk genes have been identified to date. The seizure characteristics, including focal and generalised seizures, are similar between the two species, with gene discovery facilitated by the reduced genetic heterogeneity of purebred dogs. We have recently identified a risk locus for idiopathic epilepsy in the Belgian Shepherd breed on a 4.4 megabase region on CFA37. Results We have expanded a previous study replicating the association with a combined analysis of 157 cases and 179 controls in three additional breeds: Schipperke, Finnish Spitz and Beagle (pc = 2.9e–07, pGWAS = 1.74E-02). A targeted resequencing of the 4.4 megabase region in twelve Belgian Shepherd cases and twelve controls with opposite haplotypes identified 37 case-specific variants within the ADAM23 gene. Twenty-seven variants were validated in 285 cases and 355 controls from four breeds, resulting in a strong replication of the ADAM23 locus (praw = 2.76e–15) and the identification of a common 28 kb-risk haplotype in all four breeds. Risk haplotype was present in frequencies of 0.49–0.7 in the breeds, suggesting that ADAM23 is a low penetrance risk gene for canine epilepsy. Conclusions These results implicate ADAM23 in common canine idiopathic epilepsy, although the causative variant remains yet to be identified. ADAM23 plays a role in synaptic transmission and interacts with known epilepsy genes, LGI1 and LGI2, and should be considered as a candidate gene for human epilepsies. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1651-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lotta L E Koskinen
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
| | - Eija H Seppälä
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
| | - Janelle M Belanger
- Department of Animal Science, University of California Davis, Davis, California, USA.
| | - Meharji Arumilli
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
| | - Osmo Hakosalo
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
| | - Päivi Jokinen
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
| | - Elisa M Nevalainen
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
| | - Ranno Viitmaa
- Department of Clinical Veterinary Sciences, University of Helsinki, Helsinki, Finland.
| | - Tarja S Jokinen
- Department of Clinical Veterinary Sciences, University of Helsinki, Helsinki, Finland.
| | - Anita M Oberbauer
- Department of Animal Science, University of California Davis, Davis, California, USA.
| | - Hannes Lohi
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland. .,Department of Veterinary Biosciences and Department of Medical Genetics, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland.
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42
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Dazzo E, Fanciulli M, Serioli E, Minervini G, Pulitano P, Binelli S, Di Bonaventura C, Luisi C, Pasini E, Striano S, Striano P, Coppola G, Chiavegato A, Radovic S, Spadotto A, Uzzau S, La Neve A, Giallonardo AT, Mecarelli O, Tosatto SCE, Ottman R, Michelucci R, Nobile C. Heterozygous reelin mutations cause autosomal-dominant lateral temporal epilepsy. Am J Hum Genet 2015; 96:992-1000. [PMID: 26046367 PMCID: PMC4457960 DOI: 10.1016/j.ajhg.2015.04.020] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/29/2015] [Indexed: 01/28/2023] Open
Abstract
Autosomal-dominant lateral temporal epilepsy (ADLTE) is a genetic epilepsy syndrome clinically characterized by focal seizures with prominent auditory symptoms. ADLTE is genetically heterogeneous, and mutations in LGI1 account for fewer than 50% of affected families. Here, we report the identification of causal mutations in reelin (RELN) in seven ADLTE-affected families without LGI1 mutations. We initially investigated 13 ADLTE-affected families by performing SNP-array linkage analysis and whole-exome sequencing and identified three heterozygous missense mutations co-segregating with the syndrome. Subsequent analysis of 15 small ADLTE-affected families revealed four additional missense mutations. 3D modeling predicted that all mutations have structural effects on protein-domain folding. Overall, RELN mutations occurred in 7/40 (17.5%) ADLTE-affected families. RELN encodes a secreted protein, Reelin, which has important functions in both the developing and adult brain and is also found in the blood serum. We show that ADLTE-related mutations significantly decrease serum levels of Reelin, suggesting an inhibitory effect of mutations on protein secretion. We also show that Reelin and LGI1 co-localize in a subset of rat brain neurons, supporting an involvement of both proteins in a common molecular pathway underlying ADLTE. Homozygous RELN mutations are known to cause lissencephaly with cerebellar hypoplasia. Our findings extend the spectrum of neurological disorders associated with RELN mutations and establish a link between RELN and LGI1, which play key regulatory roles in both the developing and adult brain.
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MESH Headings
- Animals
- Base Sequence
- Cell Adhesion Molecules, Neuronal/blood
- Cell Adhesion Molecules, Neuronal/chemistry
- Cell Adhesion Molecules, Neuronal/genetics
- Cell Adhesion Molecules, Neuronal/metabolism
- Chromosome Mapping
- Epilepsy, Frontal Lobe/genetics
- Epilepsy, Frontal Lobe/pathology
- Exome
- Extracellular Matrix Proteins/blood
- Extracellular Matrix Proteins/chemistry
- Extracellular Matrix Proteins/genetics
- Extracellular Matrix Proteins/metabolism
- Fluorescent Antibody Technique
- Gene Components
- Humans
- Immunoblotting
- Intercellular Signaling Peptides and Proteins
- Models, Molecular
- Molecular Sequence Data
- Mutation, Missense/genetics
- Nerve Tissue Proteins/blood
- Nerve Tissue Proteins/chemistry
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Pedigree
- Polymorphism, Single Nucleotide/genetics
- Protein Conformation
- Protein Folding
- Proteins/metabolism
- Rats
- Reelin Protein
- Sequence Analysis, DNA
- Serine Endopeptidases/blood
- Serine Endopeptidases/chemistry
- Serine Endopeptidases/genetics
- Serine Endopeptidases/metabolism
- Sleep Wake Disorders/genetics
- Sleep Wake Disorders/pathology
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Affiliation(s)
- Emanuela Dazzo
- Section of Padua, Institute of Neuroscience, Consiglio Nazionale delle Ricerche, 35121 Padova, Italy
| | | | - Elena Serioli
- Section of Padua, Institute of Neuroscience, Consiglio Nazionale delle Ricerche, 35121 Padova, Italy
| | - Giovanni Minervini
- Department of Biomedical Sciences, University of Padua, 35121 Padova, Italy
| | - Patrizia Pulitano
- Department of Neurology and Psychiatry, Sapienza University of Rome, 00185 Roma, Italy
| | - Simona Binelli
- Carlo Besta Foundation Neurological Institute, 20133 Milano, Italy
| | - Carlo Di Bonaventura
- Department of Neurology and Psychiatry, Sapienza University of Rome, 00185 Roma, Italy
| | | | - Elena Pasini
- IRCCS-Institute of Neurological Sciences, Bellaria Hospital, 40139 Bologna, Italy
| | - Salvatore Striano
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, School of Medicine, University of Naples Federico II, 80131 Napoli, Italy
| | - Pasquale Striano
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa and Giannina Gaslini Institute, 16148 Genova, Italy
| | - Giangennaro Coppola
- Child and Adolescent Psychiatry, Faculty of Medicine and Surgery, University of Salerno, 84100 Salerno, Italy
| | - Angela Chiavegato
- Section of Padua, Institute of Neuroscience, Consiglio Nazionale delle Ricerche, 35121 Padova, Italy
| | | | | | - Sergio Uzzau
- Porto Conte Ricerche, 07041 Alghero, Sassari, Italy
| | | | | | - Oriano Mecarelli
- Department of Neurology and Psychiatry, Sapienza University of Rome, 00185 Roma, Italy
| | - Silvio C E Tosatto
- Section of Padua, Institute of Neuroscience, Consiglio Nazionale delle Ricerche, 35121 Padova, Italy; Department of Biomedical Sciences, University of Padua, 35121 Padova, Italy
| | - Ruth Ottman
- Departments of Epidemiology and Neurology and the Gertrude H. Sergievsky Center, Columbia University, New York, NY 10032, USA; Division of Epidemiology, New York State Psychiatric Institute, New York, NY 10032, USA
| | - Roberto Michelucci
- IRCCS-Institute of Neurological Sciences, Bellaria Hospital, 40139 Bologna, Italy
| | - Carlo Nobile
- Section of Padua, Institute of Neuroscience, Consiglio Nazionale delle Ricerche, 35121 Padova, Italy; Department of Biomedical Sciences, University of Padua, 35121 Padova, Italy.
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Pakozdy A, Patzl M, Zimmermann L, Jokinen TS, Glantschnigg U, Kelemen A, Hasegawa D. LGI Proteins and Epilepsy in Human and Animals. J Vet Intern Med 2015; 29:997-1005. [PMID: 26032921 PMCID: PMC4895363 DOI: 10.1111/jvim.12610] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 03/23/2015] [Accepted: 04/11/2015] [Indexed: 12/16/2022] Open
Abstract
Leucine‐rich glioma‐inactivated (LGI) protein was first thought to have a suppressor effect in the formation of some cancers. Developments in physiology and medicine made it possible to characterize the function of the LGI protein family and its crucial role in different conditions more precisely. These proteins play an important role in synaptic transmission, and dysfunction may cause hyperexcitability. Genetic mutation of LGI1was confirmed to be the cause of autosomal dominant lateral temporal lobe epilepsy in humans. The LGI2 mutation was identified in benign familial juvenile epilepsy in Lagotto Romagnolo (LR) dogs. Cats with familial spontaneous temporal lobe epilepsy have been reported, and the etiology might be associated with LGI protein family dysfunction. In addition, an autoimmune reaction against LGI1 was detected in humans and cats with limbic encephalitis. These advances prompted a review of LGI protein function and its role in different seizure disorders.
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Affiliation(s)
- A Pakozdy
- University Clinic of Small Animals, University of Veterinary Medicine, Vienna, Austria
| | - M Patzl
- Institute of Immunology, University of Veterinary Medicine, Vienna, Austria
| | - L Zimmermann
- Unit of Physiology and Biophysics, University of Veterinary Medicine, Vienna, Austria
| | - T S Jokinen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - U Glantschnigg
- University Clinic of Small Animals, University of Veterinary Medicine, Vienna, Austria
| | - A Kelemen
- Epilepsy Center, National Institute of Clinical Neurosciences, Budapest, Hungary
| | - D Hasegawa
- Department of Clinical Veterinary Medicine, Nippon Veterinary and Life Science University, Musashinoshi, Tokyo, Japan
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Xie YJ, Zhou L, Jiang N, Zhang N, Zou N, Zhou L, Wang Y, Cowell JK, Shen Y. Essential roles of leucine-rich glioma inactivated 1 in the development of embryonic and postnatal cerebellum. Sci Rep 2015; 5:7827. [PMID: 25591666 PMCID: PMC4296302 DOI: 10.1038/srep07827] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 12/12/2014] [Indexed: 11/24/2022] Open
Abstract
Leucine-rich glioma inactivated 1 (LGI1) is a secreted protein that interacts with ADAM transmembrane proteins, and its mutations are linked to human epilepsy. The function of LGI1 in CNS development remains undefined. Here, we report novel functions of LGI1 in the generation of cerebellar granule precursors (CGPs) and differentiation of radial glial cells (RGCs) in the cerebellum. A reduction in external granule layer thickness and defects in foliation were seen in embryonic and new-born LGI1 knockout (KO) mice. BrdU staining showed an inhibited proliferation of CGPs in KO embryos, which might be explained by the reduced Sonic hedgehog in embryos. In addition, the differentiation of RGCs into Bergmann glias was suppressed in KO mice. Enhanced Jagged1-Notch1 signaling in KO mice via reduced β-secretase proteolysis suggests that altered phenotype of RGCs is due to abnormal Notch1 signaling. Together, our results demonstrate that LGI1 is an essential player in the cerebellar development.
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Affiliation(s)
- Ya-Jun Xie
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Liang Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Nanwei Jiang
- Zhejiang Provincial Key Laboratory of Pathophysiology, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo, China
| | - Nan Zhang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China
| | - Na Zou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Lin Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Yin Wang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China
| | - John K Cowell
- Georgia Regents University, Cancer Center, Augusta, GA, USA
| | - Ying Shen
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
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Dazzo E, Santulli L, Posar A, Fattouch J, Conti S, Lodén-van Straaten M, Mijalkovic J, De Bortoli M, Rosa M, Millino C, Pacchioni B, Di Bonaventura C, Giallonardo AT, Striano S, Striano P, Parmeggiani A, Nobile C. Autosomal dominant lateral temporal epilepsy (ADLTE): novel structural and single-nucleotide LGI1 mutations in families with predominant visual auras. Epilepsy Res 2014; 110:132-8. [PMID: 25616465 DOI: 10.1016/j.eplepsyres.2014.12.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 11/11/2014] [Accepted: 12/01/2014] [Indexed: 01/05/2023]
Abstract
PURPOSE Autosomal dominant lateral temporal epilepsy (ADLTE) is a genetic focal epilepsy syndrome characterized by prominent auditory or aphasic symptoms. Mutations in LGI1 account for less than 50% of ADLTE families. We assessed the impact of LGI1 microrearrangements in a collection of ADLTE families and sporadic lateral temporal epilepsy (LTE) patients, and investigated novel ADLTE and LTE patients. METHODS Twenty-four ADLTE families and 140 sporadic LTE patients with no evidence of point mutations in LGI1 were screened for copy number alterations using multiplex ligation-dependent probe amplification (MLPA). Newly ascertained familial and sporadic LTE patients were clinically investigated, and interictal EEG and MRI findings were obtained; probands were tested for LGI1 mutations by direct exon sequencing or denaturing high performance liquid chromatography. RESULTS We identified a novel microdeletion spanning LGI1 exon 2 in a family with two affected members, both presenting focal seizures with visual symptoms. Also, we identified a novel LGI1 missense mutation (c.1118T > C; p.L373S) in a newly ascertained family with focal seizures with prominent visual auras, and another missense mutation (c.856T > C; p.C286R) in a sporadic patient with auditory seizures. CONCLUSIONS We describe two novel ADLTE families with predominant visual auras segregating pathogenic LGI1 mutations. These findings support the notion that, in addition to auditory symptoms, other types of auras can be found in patients carrying LGI1 mutations. The identification of a novel microdeletion in LGI1, the second so far identified, suggests that LGI1 microrearrangements may not be exceptional.
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Affiliation(s)
- Emanuela Dazzo
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy
| | - Lia Santulli
- Department of Neurological Sciences, Federico II University, Napoli, Italy
| | - Annio Posar
- IRCCS-Neurological Sciences, Bellaria Hospital, Bologna, Italy
| | - Jinane Fattouch
- Department of Neurological Sciences, La Sapienza University, Roma, Italy
| | - Sara Conti
- IRCCS-Neurological Sciences, Bellaria Hospital, Bologna, Italy
| | | | | | | | - Maurizio Rosa
- Department of Biology, University of Padova, Padova, Italy
| | | | | | | | | | - Salvatore Striano
- Department of Neurological Sciences, Federico II University, Napoli, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, Institute "G. Gaslini", University of Genova, Genova, Italy
| | | | - Carlo Nobile
- CNR-Neuroscience Institute, Section of Padua, Padova, Italy.
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Yokoi N, Fukata Y, Kase D, Miyazaki T, Jaegle M, Ohkawa T, Takahashi N, Iwanari H, Mochizuki Y, Hamakubo T, Imoto K, Meijer D, Watanabe M, Fukata M. Chemical corrector treatment ameliorates increased seizure susceptibility in a mouse model of familial epilepsy. Nat Med 2014; 21:19-26. [PMID: 25485908 DOI: 10.1038/nm.3759] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/23/2014] [Indexed: 12/12/2022]
Abstract
Epilepsy is one of the most common and intractable brain disorders. Mutations in the human gene LGI1, encoding a neuronal secreted protein, cause autosomal dominant lateral temporal lobe epilepsy (ADLTE). However, the pathogenic mechanisms of LGI1 mutations remain unclear. We classified 22 reported LGI1 missense mutations as either secretion defective or secretion competent, and we generated and analyzed two mouse models of ADLTE encoding mutant proteins representative of the two groups. The secretion-defective LGI1(E383A) protein was recognized by the ER quality-control machinery and prematurely degraded, whereas the secretable LGI1(S473L) protein abnormally dimerized and was selectively defective in binding to one of its receptors, ADAM22. Both mutations caused a loss of function, compromising intracellular trafficking or ligand activity of LGI1 and converging on reduced synaptic LGI1-ADAM22 interaction. A chemical corrector, 4-phenylbutyrate (4PBA), restored LGI1(E383A) folding and binding to ADAM22 and ameliorated the increased seizure susceptibility of the LGI1(E383A) model mice. This study establishes LGI1-related epilepsy as a conformational disease and suggests new therapeutic options for human epilepsy.
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Affiliation(s)
- Norihiko Yokoi
- 1] Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan. [2] Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
| | - Yuko Fukata
- 1] Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan. [2] Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
| | - Daisuke Kase
- Division of Neural Signaling, Department of Information Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
| | - Taisuke Miyazaki
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Martine Jaegle
- Department of Cell Biology and Genetics, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Toshika Ohkawa
- 1] Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan. [2] Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
| | - Naoki Takahashi
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
| | - Hiroko Iwanari
- Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Yasuhiro Mochizuki
- 1] Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan. [2] Komaba Open Lab, PeptiDream Incorporation, Tokyo, Japan
| | - Takao Hamakubo
- Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Keiji Imoto
- 1] Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan. [2] Division of Neural Signaling, Department of Information Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
| | - Dies Meijer
- 1] Department of Cell Biology and Genetics, Erasmus University Medical Center, Rotterdam, the Netherlands. [2] Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK
| | - Masahiko Watanabe
- 1] Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Japan. [2] Japan Science and Technology Agency, Core Research for Evolutional Science and Technology, Tokyo, Japan
| | - Masaki Fukata
- 1] Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan. [2] Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
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Silva J, Sharma S, Cowell JK. Homozygous Deletion of the LGI1 Gene in Mice Leads to Developmental Abnormalities Resulting in Cortical Dysplasia. Brain Pathol 2014; 25:587-97. [PMID: 25346110 DOI: 10.1111/bpa.12225] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 10/21/2014] [Indexed: 01/02/2023] Open
Abstract
LGI1 mutations lead to an autosomal dominant form of epilepsy. Lgi1 mutant null mice develop seizures and show abnormal neuronal excitability. A fine structure analysis of the cortex in these mice demonstrated a subtle cortical dysplasia, preferentially affecting layers II-IV, associated with increased Foxp2 and Cux1-expressing neurons leading to blurring of the cortical layers. The hypercellularity observed in the null cortex resulted from an admixture of highly branched mature pyramidal neurons with short and poorly aligned axons as revealed by Golgi staining and immature small neurons with branched disoriented dendrites with reduced spine density and undersized, morphologically altered and round-headed spines. In vitro, hippocampal neurons revealed poor neurite outgrowth in null mice as well as reduced synapse formation. Electron microscopy demonstrated reduced spine-localized asymmetric (axospinous) synapses with postsynaptic densities and vesicle-loaded synapses in the mutant null cortex. The overall pathology in the null mice suggested cortical dyslamination most likely because of mislocalization of late-born neurons, with an admixture of those carrying suboptimally developed axons and dendrites with reduced functional synapses with normal neurons. Our study suggests that LGI1 has a role in regulating cortical development, which is increasingly becoming recognized as one of the causes of idiopathic epilepsy.
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Affiliation(s)
- Jeane Silva
- Cancer Center, Georgia Regents University, Augusta, GA
| | - Suash Sharma
- Cancer Center, Georgia Regents University, Augusta, GA.,Department of Pathology, Georgia Regents University, Augusta, GA
| | - John K Cowell
- Cancer Center, Georgia Regents University, Augusta, GA.,Department of Pathology, Georgia Regents University, Augusta, GA
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Boillot M, Huneau C, Marsan E, Lehongre K, Navarro V, Ishida S, Dufresnois B, Ozkaynak E, Garrigue J, Miles R, Martin B, Leguern E, Anderson MP, Baulac S. Glutamatergic neuron-targeted loss of LGI1 epilepsy gene results in seizures. ACTA ACUST UNITED AC 2014; 137:2984-96. [PMID: 25234641 DOI: 10.1093/brain/awu259] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Leucin-rich, glioma inactivated 1 (LGI1) is a secreted protein linked to human seizures of both genetic and autoimmune aetiology. Mutations in the LGI1 gene are responsible for autosomal dominant temporal lobe epilepsy with auditory features, whereas LGI1 autoantibodies are involved in limbic encephalitis, an acquired epileptic disorder associated with cognitive impairment. We and others previously reported that Lgi1-deficient mice have early-onset spontaneous seizures leading to premature death at 2-3 weeks of age. Yet, where and when Lgi1 deficiency causes epilepsy remains unknown. To address these questions, we generated Lgi1 conditional knockout (cKO) mice using a set of universal Cre-driver mouse lines. Selective deletion of Lgi1 was achieved in glutamatergic pyramidal neurons during embryonic (Emx1-Lgi1cKO) or late postnatal (CaMKIIα-Lgi1cKO) developmental stages, or in gamma amino butyric acidergic (GABAergic) parvalbumin interneurons (PV-Lgi1cKO). Emx1-Lgi1cKO mice displayed early-onset and lethal seizures, whereas CaMKIIα-Lgi1cKO mice presented late-onset occasional seizures associated with variable reduced lifespan. In contrast, neither spontaneous seizures nor increased seizure susceptibility to convulsant were observed when Lgi1 was deleted in parvalbumin interneurons. Together, these data showed that LGI1 depletion restricted to pyramidal cells is sufficient to generate seizures, whereas seizure thresholds were unchanged after depletion in gamma amino butyric acidergic parvalbumin interneurons. We suggest that LGI1 secreted from excitatory neurons, but not parvalbumin inhibitory neurons, makes a major contribution to the pathogenesis of LGI1-related epilepsies. Our data further indicate that LGI1 is required from embryogenesis to adulthood to achieve proper circuit functioning.
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Affiliation(s)
- Morgane Boillot
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Clément Huneau
- 5 Université de Rennes 1, LTSI, F-35000, Rennes, France 6 INSERM, U1099, F-35000, Rennes, France
| | - Elise Marsan
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Katia Lehongre
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Vincent Navarro
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France 7 AP-HP, Hôpital de la Pitié-Salpêtrière, Epilepsy Unit, F-75013, Paris, France
| | - Saeko Ishida
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Béatrice Dufresnois
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Ekim Ozkaynak
- 8 Departments of Neurology and Pathology, Beth Israel Deaconess Medical Centre and Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Jérôme Garrigue
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Richard Miles
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Benoit Martin
- 5 Université de Rennes 1, LTSI, F-35000, Rennes, France 6 INSERM, U1099, F-35000, Rennes, France
| | - Eric Leguern
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France 9 AP-HP, Hôpital de la Pitié-Salpêtrière, Département de Génétique et de Cytogénétique, F-75013, Paris, France
| | - Matthew P Anderson
- 8 Departments of Neurology and Pathology, Beth Israel Deaconess Medical Centre and Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Stéphanie Baulac
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
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Olivetti PR, Maheshwari A, Noebels JL. Neonatal estradiol stimulation prevents epilepsy in Arx model of X-linked infantile spasms syndrome. Sci Transl Med 2014; 6:220ra12. [PMID: 24452264 DOI: 10.1126/scitranslmed.3007231] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Infantile spasms are a catastrophic form of pediatric epilepsy with inadequate treatment. In patients, mutation of ARX, a transcription factor selectively expressed in neuronal precursors and adult inhibitory interneurons, impairs cell migration and causes a major inherited subtype of the disease X-linked infantile spasms syndrome. Using an animal model, the Arx((GCG)10+7) mouse, we determined that brief estradiol (E2) administration during early postnatal development prevented spasms in infancy and seizures in adult mutants. E2 was ineffective when delivered after puberty or 30 days after birth. Early E2 treatment altered mRNA levels of three downstream targets of Arx (Shox2, Ebf3, and Lgi1) and restored depleted interneuron populations without increasing GABAergic synaptic density. Postnatal E2 treatment may induce lasting transcriptional changes that lead to enduring disease modification and could potentially serve as a therapy for inherited interneuronopathies.
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Affiliation(s)
- Pedro R Olivetti
- Blue Bird Circle Developmental Neurogenetics Laboratory, Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
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50
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Guerrini R, Marini C, Mantegazza M. Genetic epilepsy syndromes without structural brain abnormalities: clinical features and experimental models. Neurotherapeutics 2014; 11:269-85. [PMID: 24664660 PMCID: PMC3996114 DOI: 10.1007/s13311-014-0267-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Research in genetics of epilepsy represents an area of great interest both for clinical purposes and for understanding the basic mechanisms of epilepsy. Most mutations in epilepsies without structural brain abnormalities have been identified in ion channel genes, but an increasing number of genes involved in a diversity of functional and developmental processes are being recognized through whole exome or genome sequencing. Targeted molecular diagnosis is now available for different forms of epilepsy. The identification of epileptogenic mutations in patients before epilepsy onset and the possibility of developing therapeutic strategies tested in experimental models may facilitate experimental approaches that prevent epilepsy or decrease its severity. Functional analysis is essential for better understanding pathogenic mechanisms and gene interactions. In vitro experimental systems are either cells that usually do not express the protein of interest or neurons in primary cultures. In vivo/ex vivo systems are organisms or preparations obtained from them (e.g., brain slices), which should better model the complexity of brain circuits and actual pathophysiological conditions. Neurons differentiated from induced pluripotent stem cells generated from the skin fibroblasts of patients have recently allowed the study of mutations in human neurons having the genetic background of a given patient. However, there is remarkable complexity underlying epileptogenesis in the clinical dimension, as reflected by the fact that experimental models have not provided yet results having clinical translation and that, with a few exceptions concerning rare conditions, no new curative treatment has emerged from any genetic finding in epilepsy.
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Affiliation(s)
- Renzo Guerrini
- Pediatric Neurology Unit and Laboratories, Children's Hospital A. Meyer-University of Florence, Viale Pieraccini 24, 50139, Florence, Italy,
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