1
|
Hardy D, Buhler E, Suchkov D, Vinck A, Fortoul A, Watrin F, Represa A, Minlebaev M, Manent JB. Early suppression of excitability in subcortical band heterotopia modifies epileptogenesis in rats. Neurobiol Dis 2023; 177:106002. [PMID: 36649744 DOI: 10.1016/j.nbd.2023.106002] [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: 10/10/2022] [Revised: 01/04/2023] [Accepted: 01/13/2023] [Indexed: 01/15/2023] Open
Abstract
Malformations of cortical development represent a major cause of epilepsy in childhood. However, the pathological substrate and dynamic changes leading to the development and progression of epilepsy remain unclear. Here, we characterized an etiology-relevant rat model of subcortical band heterotopia (SBH), a diffuse type of cortical malformation associated with drug-resistant seizures in humans. We used longitudinal electrographic recordings to monitor the age-dependent evolution of epileptiform discharges during the course of epileptogenesis in this model. We found both quantitative and qualitative age-related changes in seizures properties and patterns, accompanying a gradual progression towards a fully developed seizure pattern seen in adulthood. We also dissected the relative contribution of the band heterotopia and the overlying cortex to the development and age-dependent progression of epilepsy using timed and spatially targeted manipulation of neuronal excitability. We found that an early suppression of neuronal excitability in SBH slows down epileptogenesis in juvenile rats, whereas epileptogenesis is paradoxically exacerbated when excitability is suppressed in the overlying cortex. However, in rats with active epilepsy, similar manipulations of excitability have no effect on chronic spontaneous seizures. Together, our data support the notion that complex developmental alterations occurring in both the SBH and the overlying cortex concur to creating pathogenic circuits prone to generate seizures. Our study also suggests that early and targeted interventions could potentially influence the course of these altered developmental trajectories, and favorably modify epileptogenesis in malformations of cortical development.
Collapse
Affiliation(s)
- Delphine Hardy
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Emmanuelle Buhler
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Dmitrii Suchkov
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Antonin Vinck
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Aurélien Fortoul
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Françoise Watrin
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Alfonso Represa
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Marat Minlebaev
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France
| | - Jean-Bernard Manent
- INMED, INSERM, Aix-Marseille University, Turing Centre for Living Systems, Marseille, France.
| |
Collapse
|
2
|
Markus F, Kannengießer A, Näder P, Atigbire P, Scholten A, Vössing C, Bültmann E, Korenke GC, Owczarek-Lipska M, Neidhardt J. A novel missense variant in the EML1 gene associated with bilateral ribbon-like subcortical heterotopia leads to ciliary defects. J Hum Genet 2021; 66:1159-1167. [PMID: 34211111 PMCID: PMC8612930 DOI: 10.1038/s10038-021-00947-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 02/06/2023]
Abstract
Heterotopia is a brain malformation caused by a failed migration of cortical neurons during development. Clinical symptoms of heterotopia vary in severity of intellectual disability and may be associated with epileptic disorders. Abnormal neuronal migration is known to be associated with mutations in the doublecortin gene (DCX), the platelet-activating factor acetylhydrolase gene (PAFAH1B1), or tubulin alpha-1A gene (TUBA1A). Recently, a new gene encoding echinoderm microtubule-associated protein-like 1 (EML1) was reported to cause a particular form of subcortical heterotopia, the ribbon-like subcortical heterotopia (RSH). EML1 mutations are inherited in an autosomal recessive manner. Only six unrelated EML1-associated heterotopia-affected families were reported so far. The EML1 protein is a member of the microtubule-associated proteins family, playing an important role in microtubule assembly and stabilization as well as in mitotic spindle formation in interphase. Herein, we present a novel homozygous missense variant in EML1 (NM_004434.2: c.692G>A, NP_004425.2: p.Gly231Asp) identified in a male RSH-affected patient. Our clinical and molecular findings confirm the genotype-phenotype associations of EML1 mutations and RSH. Analyses of patient-derived fibroblasts showed the significantly reduced length of primary cilia. In addition, our results presented, that the mutated EML1 protein did not change binding capacities with tubulin. The data described herein will expand the mutation spectrum of the EML1 gene and provide further insight into molecular and cellular bases of the pathogenic mechanisms underlying RSH.
Collapse
Affiliation(s)
- Fenja Markus
- grid.5560.60000 0001 1009 3608Junior Research Group, Genetics of Childhood Brain Malformations, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany ,grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Annika Kannengießer
- grid.5560.60000 0001 1009 3608Junior Research Group, Genetics of Childhood Brain Malformations, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany ,grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Patricia Näder
- grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Paul Atigbire
- grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Alexander Scholten
- grid.5560.60000 0001 1009 3608Division of Biochemistry, Biochemistry of signal transduction/neurosensory processes, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Christine Vössing
- grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Eva Bültmann
- grid.10423.340000 0000 9529 9877Institute of Diagnostic and Interventional Neuroradiology, Hannover Medical School, Hannover, Germany
| | - G. Christoph Korenke
- grid.419838.f0000 0000 9806 6518Department of Neuropediatrics, University Children’s Hospital, Klinikum Oldenburg, Oldenburg, Germany
| | - Marta Owczarek-Lipska
- grid.5560.60000 0001 1009 3608Junior Research Group, Genetics of Childhood Brain Malformations, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany ,grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany ,grid.5560.60000 0001 1009 3608Research Center Neurosensory Science, University of Oldenburg, Oldenburg, Germany
| | - John Neidhardt
- grid.5560.60000 0001 1009 3608Human Genetics, Faculty VI-School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany ,grid.5560.60000 0001 1009 3608Research Center Neurosensory Science, University of Oldenburg, Oldenburg, Germany
| |
Collapse
|
3
|
Martineau FS, Sahu S, Plantier V, Buhler E, Schaller F, Fournier L, Chazal G, Kawasaki H, Represa A, Watrin F, Manent JB. Correct Laminar Positioning in the Neocortex Influences Proper Dendritic and Synaptic Development. Cereb Cortex 2019; 28:2976-2990. [PMID: 29788228 PMCID: PMC6041803 DOI: 10.1093/cercor/bhy113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Indexed: 01/28/2023] Open
Abstract
The neocortex is a 6-layered laminated structure with a precise anatomical and functional organization ensuring proper function. Laminar positioning of cortical neurons, as determined by termination of neuronal migration, is a key determinant of their ability to assemble into functional circuits. However, the exact contribution of laminar placement to dendrite morphogenesis and synapse formation remains unclear. Here we manipulated the laminar position of cortical neurons by knocking down doublecortin (Dcx), a crucial effector of migration, and show that misplaced neurons fail to properly form dendrites, spines, and functional glutamatergic and GABAergic synapses. We further show that knocking down Dcx in properly positioned neurons induces similar but milder defects, suggesting that the laminar misplacement is the primary cause of altered neuronal development. Thus, the specific laminar environment of their fated layers is crucial for the maturation of cortical neurons, and influences their functional integration into developing cortical circuits.
Collapse
Affiliation(s)
| | - Surajit Sahu
- INMED, Aix-Marseille University, INSERM U901, Marseille, France
| | | | | | | | | | | | - Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Ishikawa, Japan
| | - Alfonso Represa
- INMED, Aix-Marseille University, INSERM U901, Marseille, France
| | | | | |
Collapse
|
4
|
Martineau FS, Fournier L, Buhler E, Watrin F, Sargolini F, Manent JB, Poucet B, Represa A. Spared cognitive and behavioral functions prior to epilepsy onset in a rat model of subcortical band heterotopia. Brain Res 2019; 1711:146-155. [PMID: 30689978 DOI: 10.1016/j.brainres.2019.01.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/23/2019] [Accepted: 01/24/2019] [Indexed: 11/17/2022]
Abstract
Subcortical band heterotopia (SBH), also known as doublecortex syndrome, is a malformation of cortical development resulting from mutations in the doublecortin gene (DCX). It is characterized by a lack of migration of cortical neurons that accumulate in the white matter forming a heterotopic band. Patients with SBH may present mild to moderate intellectual disability as well as epilepsy. The SBH condition can be modeled in rats by in utero knockdown (KD) of Dcx. The affected cells form an SBH reminiscent of that observed in human patients and the animals develop a chronic epileptic condition in adulthood. Here, we investigated if the presence of a SBH is sufficient to induce cognitive impairment in juvenile Dcx-KD rats, before the onset of epilepsy. Using a wide range of behavioral tests, we found that the presence of SBH did not appear to affect motor control or somatosensory processing. In addition, cognitive abilities such as learning, short-term and long-term memory, were normal in pre-epileptic Dcx-KD rats. We suggest that the SBH presence is not sufficient to impair these behavioral functions.
Collapse
Affiliation(s)
| | - Lauriane Fournier
- INMED, Aix-Marseille University, INSERM U1249, Marseille 13273 CEDEX 09, France
| | - Emmanuelle Buhler
- INMED, Aix-Marseille University, INSERM U1249, Marseille 13273 CEDEX 09, France
| | - Françoise Watrin
- INMED, Aix-Marseille University, INSERM U1249, Marseille 13273 CEDEX 09, France
| | - Francesca Sargolini
- LNC - Fédération de recherche 3C, Aix-Marseille University, CNRS UMR7291, Marseille 13331 CEDEX 03, France
| | - Jean-Bernard Manent
- INMED, Aix-Marseille University, INSERM U1249, Marseille 13273 CEDEX 09, France
| | - Bruno Poucet
- LNC - Fédération de recherche 3C, Aix-Marseille University, CNRS UMR7291, Marseille 13331 CEDEX 03, France
| | - Alfonso Represa
- INMED, Aix-Marseille University, INSERM U1249, Marseille 13273 CEDEX 09, France.
| |
Collapse
|
5
|
Sprugnoli G, Vatti G, Rossi S, Cerase A, Renieri A, Mencarelli MA, Zara F, Rossi A, Santarnecchi E. Functional Connectivity and Genetic Profile of a "Double-Cortex"-Like Malformation. Front Integr Neurosci 2018; 12:22. [PMID: 29946244 PMCID: PMC6005822 DOI: 10.3389/fnint.2018.00022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/22/2018] [Indexed: 11/13/2022] Open
Abstract
Laminar heterotopia is a rare condition consisting in an extra layer of gray matter under properly migrated cortex; it configures an atypical presentation of periventricular nodular heterotopia (PNH) or a double cortex (DC) syndrome. We conducted an original functional MRI (fMRI) analysis in a drug-resistant epilepsy patient with “double-cortex”-like malformation to reveal her functional connectivity (FC) as well as a wide genetic analysis to identify possible genetic substrates. Heterotopias were segmented into region of interests (ROIs), whose voxel-wise FC was compared to that of (i) its normally migrated counterpart, (ii) its contralateral homologous, and (iii) those of 30 age-matched healthy controls. Extensive genetic analysis was conducted to screen cortical malformations-associated genes. Compared to healthy controls, both laminar heterotopias and the overlying cortex showed significant reduction of FC with the contralateral hemisphere. Two heterozygous variants of uncertain clinical significance were found, involving autosomal recessive disease-causing genes, FAT4 and COL18A1. This first FC analysis of a unique case of “double-cortex”-like malformation revealed a hemispheric connectivity segregation both in the laminar cortex as in the correctly migrated one, with a new pattern of genes’ mutations. Our study suggests the altered FC could have an electrophysiological and functional impact on large-scale brain networks, and the involvement of not yet identified genes in “double-cortex”-like malformation with a possible role of rare variants in recessive genes as pathogenic cofactors.
Collapse
Affiliation(s)
- Giulia Sprugnoli
- Department of Medicine, Surgery and Neuroscience, Brain Investigation & Neuromodulation Laboratory, University of Siena, Siena, Italy.,Department of Medicine, Surgery and Neuroscience, Neurology and Clinical Neurophysiology Section, University of Siena, Siena, Italy
| | - Giampaolo Vatti
- Department of Medicine, Surgery and Neuroscience, Neurology and Clinical Neurophysiology Section, University of Siena, Siena, Italy
| | - Simone Rossi
- Department of Medicine, Surgery and Neuroscience, Brain Investigation & Neuromodulation Laboratory, University of Siena, Siena, Italy.,Department of Medicine, Surgery and Neuroscience, Neurology and Clinical Neurophysiology Section, University of Siena, Siena, Italy
| | - Alfonso Cerase
- Department of Medicine, Surgery and Neuroscience, Section of Neuroradiology, University of Siena, Siena, Italy
| | - Alessandra Renieri
- Department of Medicine, Surgery and Neuroscience, Section of Medical Genetics, University of Siena, Siena, Italy
| | - Maria A Mencarelli
- Department of Medicine, Surgery and Neuroscience, Section of Medical Genetics, University of Siena, Siena, Italy
| | - Federico Zara
- Laboratory of Neurogenetics and Neuroscience, Istituto Giannina Gaslini, Genoa, Italy
| | - Alessandro Rossi
- Department of Medicine, Surgery and Neuroscience, Brain Investigation & Neuromodulation Laboratory, University of Siena, Siena, Italy.,Department of Medicine, Surgery and Neuroscience, Neurology and Clinical Neurophysiology Section, University of Siena, Siena, Italy
| | - Emiliano Santarnecchi
- Department of Medicine, Surgery and Neuroscience, Brain Investigation & Neuromodulation Laboratory, University of Siena, Siena, Italy.,Department of Medicine, Surgery and Neuroscience, Neurology and Clinical Neurophysiology Section, University of Siena, Siena, Italy.,Department of Cognitive Neurology, Beth Israel Deaconess Medical Center, Berenson-Allen Center for Noninvasive Brain Stimulation, Harvard Medical School, Boston, MA, United States
| |
Collapse
|
6
|
Teplyshova AM, Gaskin VV, Kustov GV, Gudkova AA, Luzin RV, Trifonov IS, Lebedeva AV. [Subcortical laminar heterotopia 'double cortex syndrome']. Zh Nevrol Psikhiatr Im S S Korsakova 2017; 117:75-79. [PMID: 29213043 DOI: 10.17116/jnevro20171179275-79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This article presents a clinical case of a 29-year-old patient with 'Double cortex syndrome' with epilepsy, intellectual and mental disorders. Subcortical band heterotopia is a rare disorder of neuronal migration. Such patients typically present with epilepsy and variable degrees of mental retardation and behavioral and intellectual disturbances. The main diagnostic method is magnetic resonance imaging (MRI).
Collapse
Affiliation(s)
- A M Teplyshova
- Moscow Research and Clinical Center for Neuropsychiatry, Moscow, Russia
| | - V V Gaskin
- Moscow Research and Clinical Center for Neuropsychiatry, Moscow, Russia
| | - G V Kustov
- Moscow Research and Clinical Center for Neuropsychiatry, Moscow, Russia
| | - A A Gudkova
- Moscow Research and Clinical Center for Neuropsychiatry, Moscow, Russia; Pirogov Russian National Research Medical University, Moscow, Russia
| | - R V Luzin
- Moscow Research and Clinical Center for Neuropsychiatry, Moscow, Russia, Pirogov Russian National Research Medical University, Moscow, Russia, Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russia
| | - I S Trifonov
- Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russia
| | - A V Lebedeva
- Moscow Research and Clinical Center for Neuropsychiatry, Moscow, Russia; Pirogov Russian National Research Medical University, Moscow, Russia
| |
Collapse
|
7
|
Petit LF, Jalabert M, Buhler E, Malvache A, Peret A, Chauvin Y, Watrin F, Represa A, Manent JB. Normotopic cortex is the major contributor to epilepsy in experimental double cortex. Ann Neurol 2014; 76:428-42. [PMID: 25074818 DOI: 10.1002/ana.24237] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 07/08/2014] [Accepted: 07/21/2014] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Subcortical band heterotopia (SBH) is a cortical malformation formed when neocortical neurons prematurely stop their migration in the white matter, forming a heterotopic band below the normotopic cortex, and is generally associated with intractable epilepsy. Although it is clear that the band heterotopia and the overlying cortex both contribute to creating an abnormal circuit prone to generate epileptic discharges, it is less understood which part of this circuitry is the most critical. Here, we sought to identify the origin of epileptiform activity in a targeted genetic model of SBH in rats. METHODS Rats with SBH (Dcx-KD rats) were generated by knocking down the Dcx gene using shRNA vectors transfected into neocortical progenitors of rat embryos. Origin, spatial extent, and laminar profile of bicuculline-induced interictal-like activity on neocortical slices were analyzed by using extracellular recordings from 60-channel microelectrode arrays. Susceptibility to pentylenetetrazole-induced seizures was assessed by electrocorticography in head-restrained nonanesthetized rats. RESULTS We show that the band heterotopia does not constitute a primary origin for interictal-like epileptiform activity in vitro and is dispensable for generating induced seizures in vivo. Furthermore, we report that most interictal-like discharges originating in the overlying cortex secondarily propagate to the band heterotopia. Importantly, we found that in vivo suppression of neuronal excitability in SBH does not alter the higher propensity of Dcx-KD rats to display seizures. INTERPRETATION These results suggest a major role of the normotopic cortex over the band heterotopia in generating interictal epileptiform activity and seizures in brains with SBH.
Collapse
Affiliation(s)
- Ludovic Franck Petit
- Institut de Neurobiologie de la Méditerranée/Institut National de la Santé et de la Recherche Médicale U901, Marseille, France; Aix-Marseille University, Marseille, France
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Lapray D, Popova IY, Kindler J, Jorquera I, Becq H, Manent JB, Luhmann HJ, Represa A. Spontaneous Epileptic Manifestations in a DCX Knockdown Model of Human Double Cortex. Cereb Cortex 2010; 20:2694-701. [DOI: 10.1093/cercor/bhq014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|