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Johnson JP, Focken T, Karimi Tari P, Dube C, Goodchild SJ, Andrez JC, Bankar G, Burford K, Chang E, Chowdhury S, Christabel J, Dean R, de Boer G, Dehnhardt C, Gong W, Grimwood M, Hussainkhel A, Jia Q, Khakh K, Lee S, Li J, Lin S, Lindgren A, Lofstrand V, Mezeyova J, Nelkenbrecher K, Shuart NG, Sojo L, Sun S, Waldbrook M, Wesolowski S, Wilson M, Xie Z, Zenova A, Zhang W, Scott FL, Cutts AJ, Sherrington RP, Winquist R, Cohen CJ, Empfield JR. The contribution of Na V1.6 to the efficacy of voltage-gated sodium channel inhibitors in wild type and Na V1.6 gain-of-function (GOF) mouse seizure control. Br J Pharmacol 2024. [PMID: 38922847 DOI: 10.1111/bph.16481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 04/19/2024] [Accepted: 05/15/2024] [Indexed: 06/28/2024] Open
Abstract
BACKGROUND AND PURPOSE Inhibitors of voltage-gated sodium channels (NaVs) are important anti-epileptic drugs, but the contribution of specific channel isoforms is unknown since available inhibitors are non-selective. We aimed to create novel, isoform selective inhibitors of Nav channels as a means of informing the development of improved antiseizure drugs. EXPERIMENTAL APPROACH We created a series of compounds with diverse selectivity profiles enabling block of NaV1.6 alone or together with NaV1.2. These novel NaV inhibitors were evaluated for their ability to inhibit electrically evoked seizures in mice with a heterozygous gain-of-function mutation (N1768D/+) in Scn8a (encoding NaV1.6) and in wild-type mice. KEY RESULTS Pharmacologic inhibition of NaV1.6 in Scn8aN1768D/+ mice prevented seizures evoked by a 6-Hz shock. Inhibitors were also effective in a direct current maximal electroshock seizure assay in wild-type mice. NaV1.6 inhibition correlated with efficacy in both models, even without inhibition of other CNS NaV isoforms. CONCLUSIONS AND IMPLICATIONS Our data suggest NaV1.6 inhibition is a driver of efficacy for NaV inhibitor anti-seizure medicines. Sparing the NaV1.1 channels of inhibitory interneurons did not compromise efficacy. Selective NaV1.6 inhibitors may provide targeted therapies for human Scn8a developmental and epileptic encephalopathies and improved treatments for idiopathic epilepsies.
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Affiliation(s)
- James P Johnson
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Thilo Focken
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Parisa Karimi Tari
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Celine Dube
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Samuel J Goodchild
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | | | - Girish Bankar
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Kristen Burford
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Elaine Chang
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Sultan Chowdhury
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Jessica Christabel
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Richard Dean
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Gina de Boer
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Christoph Dehnhardt
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Wei Gong
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Michael Grimwood
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Angela Hussainkhel
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Qi Jia
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Kuldip Khakh
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Stephanie Lee
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Jenny Li
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Sophia Lin
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Andrea Lindgren
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Verner Lofstrand
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Janette Mezeyova
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Karen Nelkenbrecher
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Noah Gregory Shuart
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Luis Sojo
- Department of Compound Properties, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Shaoyi Sun
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Matthew Waldbrook
- Department of In Vivo Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Steven Wesolowski
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Michael Wilson
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Zhiwei Xie
- Department of In Vitro Biology, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Alla Zenova
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Wei Zhang
- Department of Chemistry, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | | | - Alison J Cutts
- Scientific Affairs, Xenon Pharmaceuticals, Inc, Burnaby, British Columbia, Canada
| | - Robin P Sherrington
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Raymond Winquist
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - Charles J Cohen
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
| | - James R Empfield
- Executive Team, Xenon Pharmaceuticals Inc, Burnaby, British Columbia, Canada
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Knowles J. Attentional Deficits and Absence Epilepsy: A Tale of 2 Interneuronopathies. Epilepsy Curr 2024; 24:188-190. [PMID: 38898911 PMCID: PMC11185201 DOI: 10.1177/15357597241251709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/22/2024] [Accepted: 04/08/2024] [Indexed: 06/21/2024] Open
Abstract
Prefrontal PV Interneurons Facilitate Attention and Are Linked to Attentional Dysfunction in a Mouse Model of Absence Epilepsy Ferguson B, Glick C, Huguenard JR. Elife . 2023;12:e78349. doi:10.7554/eLife.78349 Absence seizures are characterized by brief periods of unconsciousness accompanied by lapses in motor function that can occur hundreds of times throughout the day. Outside of these frequent moments of unconsciousness, approximately a third of people living with the disorder experience treatment-resistant attention impairments. Convergent evidence suggests prefrontal cortex (PFC) dysfunction may underlie attention impairments in affected patients. To examine this, we use a combination of slice physiology, fiber photometry, electrocorticography (ECoG), optogenetics, and behavior in the Scn8a+/-mouse model of absence epilepsy. Attention function was measured using a novel visual attention task where a light cue that varied in duration predicted the location of a food reward. In Scn8a+/-mice, we find altered parvalbumin interneuron (PVIN) output in the medial PFC (mPFC) in vitro and PVIN hypoactivity along with reductions in gamma power during cue presentation in vivo. This was associated with poorer attention performance in Scn8a+/-mice that could be rescued by gamma-frequency optogenetic stimulation of PVINs. This highlights cue-related PVIN activity as an important mechanism for attention and suggests PVINs may represent a therapeutic target for cognitive comorbidities in absence epilepsy.
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Dimwamwa ED, Pala A, Chundru V, Wright NC, Stanley GB. Dynamic corticothalamic modulation of the somatosensory thalamocortical circuit during wakefulness. Nat Commun 2024; 15:3529. [PMID: 38664415 PMCID: PMC11045850 DOI: 10.1038/s41467-024-47863-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
The feedback projections from cortical layer 6 (L6CT) to the sensory thalamus have long been implicated in playing a primary role in gating sensory signaling but remain poorly understood. To causally elucidate the full range of effects of these projections, we targeted silicon probe recordings to the whisker thalamocortical circuit of awake mice selectively expressing Channelrhodopsin-2 in L6CT neurons. Through optogenetic manipulation of L6CT neurons, multi-site electrophysiological recordings, and modeling of L6CT circuitry, we establish L6CT neurons as dynamic modulators of ongoing spiking in the ventral posteromedial nucleus of the thalamus (VPm), either suppressing or enhancing VPm spiking depending on L6CT neurons' firing rate and synchrony. Differential effects across the cortical excitatory and inhibitory sub-populations point to an overall influence of L6CT feedback on cortical excitability that could have profound implications for regulating sensory signaling across a range of ethologically relevant conditions.
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Affiliation(s)
- Elaida D Dimwamwa
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Aurélie Pala
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Vivek Chundru
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Nathaniel C Wright
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Garrett B Stanley
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
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Hill SF, Yu W, Ziobro J, Chalasani S, Reger F, Meisler MH. Long-Term Downregulation of the Sodium Channel Gene Scn8a Is Therapeutic in Mouse Models of SCN8A Epilepsy. Ann Neurol 2024; 95:754-759. [PMID: 38113311 PMCID: PMC11170564 DOI: 10.1002/ana.26861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 11/06/2023] [Accepted: 12/14/2023] [Indexed: 12/21/2023]
Abstract
OBJECTIVE De novo mutations of the voltage-gated sodium channel gene SCN8A cause developmental and epileptic encephalopathy (DEE). Most pathogenic variants result in gain-of-function changes in activity of the sodium channel Nav1.6, poorly controlled seizures, and significant comorbidities. In previous work, an antisense oligonucleotide (ASO) reduced Scn8a transcripts and increased lifespan after neonatal administration to a mouse model. Here, we tested long-term ASO treatment initiated after seizure onset, as required for clinical application. METHODS ASO treatment was initiated after observation of a convulsive seizure and repeated at 4 to 6 week intervals for 1 year. We also tested the long-term efficacy of an AAV10-short hairpin RNA (shRNA) virus administered on P1. RESULTS Repeated treatment with the Scn8a ASO initiated after seizure onset provided long-term survival and reduced seizure frequency during a 12 month observation period. A single treatment with viral shRNA was also protective during 12 months of observation. INTERPRETATION Downregulation of Scn8a expression that is initiated after the onset of seizures is effective for long-term treatment in a model of SCN8A-DEE. Repeated ASO administration or a single dose of viral shRNA prevented seizures and extended survival through 12 months of observation. ANN NEUROL 2024;95:754-759.
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Affiliation(s)
- Sophie F Hill
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States
- Department of Human Genetics, University of Michigan, Ann Arbor, MI
| | - Wenxi Yu
- Department of Human Genetics, University of Michigan, Ann Arbor, MI
| | - Julie Ziobro
- Department of Pediatrics, University of Michigan, Ann Arbor, MI
| | - Sanjna Chalasani
- Department of Human Genetics, University of Michigan, Ann Arbor, MI
| | - Faith Reger
- Department of Human Genetics, University of Michigan, Ann Arbor, MI
| | - Miriam H Meisler
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States
- Department of Human Genetics, University of Michigan, Ann Arbor, MI
- Department of Neurology, University of Michigan, Ann Arbor, MI
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5
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Yang Y, Chen Z, Zhou J, Jiang S, Wang G, Wan L, Yu J, Jiang M, Wang Y, Hu J, Liu X, Wang Y. Anti-PD-1 treatment protects against seizure by suppressing sodium channel function. CNS Neurosci Ther 2024; 30:e14504. [PMID: 37904722 PMCID: PMC11017438 DOI: 10.1111/cns.14504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 10/05/2023] [Accepted: 10/06/2023] [Indexed: 11/01/2023] Open
Abstract
AIMS Although programmed cell death protein 1 (PD-1) typically serves as a target for immunotherapies, a few recent studies have found that PD-1 is expressed in the nervous system and that neuronal PD-1 might play a crucial role in regulating neuronal excitability. However, whether brain-localized PD-1 is involved in seizures and epileptogenesis is still unknown and worthy of in-depth exploration. METHODS The existence of PD-1 in human neurons was confirmed by immunohistochemistry, and PD-1 expression levels were measured by real-time quantitative PCR (RT-qPCR) and western blotting. Chemoconvulsants, pentylenetetrazol (PTZ) and cyclothiazide (CTZ), were applied for the establishment of in vivo (rodents) and in vitro (primary hippocampal neurons) models of seizure, respectively. SHR-1210 (a PD-1 monoclonal antibody) and sodium stibogluconate (SSG, a validated inhibitor of SH2-containing protein tyrosine phosphatase-1 [SHP-1]) were administrated to investigate the impact of PD-1 pathway blockade on epileptic behaviors of rodents and epileptiform discharges of neurons. A miRNA strategy was applied to determine the impact of PD-1 knockdown on neuronal excitability. The electrical activities and sodium channel function of neurons were determined by whole-cell patch-clamp recordings. The interaction between PD-1 and α-6 subunit of human voltage-gated sodium channel (Nav1.6) was validated by performing co-immunostaining and co-immunoprecipitation (co-IP) experiments. RESULTS Our results reveal that PD-1 protein and mRNA levels were upregulated in lesion cores compared with perifocal tissues of surgically resected specimens from patients with intractable epilepsy. Furthermore, we show that anti-PD-1 treatment has anti-seizure effects both in vivo and in vitro. Then, we reveal that PD-1 blockade can alter the electrophysiological properties of sodium channels. Moreover, we reveal that PD-1 acts together with downstream SHP-1 to regulate sodium channel function and hence neuronal excitability. Further investigation suggests that there is a direct interaction between neuronal PD-1 and Nav1.6. CONCLUSION Our study reveals that neuronal PD-1 plays an important role in epilepsy and that anti-PD-1 treatment protects against seizures by suppressing sodium channel function, identifying anti-PD-1 treatment as a novel therapeutic strategy for epilepsy.
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Affiliation(s)
- Yuling Yang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
| | - Zhiyun Chen
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
| | - Jing Zhou
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
- Rehabilitation CenterShenzhen Second People's Hospital/The First Affiliated Hospital of Shenzhen University Health Science CenterShenzhenChina
| | - Shize Jiang
- Department of Neurosurgery, Huashan HospitalFudan UniversityShanghaiChina
| | - Guoxiang Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
| | - Li Wan
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
- Rehabilitation CenterShenzhen Second People's Hospital/The First Affiliated Hospital of Shenzhen University Health Science CenterShenzhenChina
| | - Jiangning Yu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
| | - Min Jiang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
| | - Yulong Wang
- Rehabilitation CenterShenzhen Second People's Hospital/The First Affiliated Hospital of Shenzhen University Health Science CenterShenzhenChina
| | - Jie Hu
- Department of Neurosurgery, Huashan HospitalFudan UniversityShanghaiChina
| | - Xu Liu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
| | - Yun Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan HospitalFudan UniversityShanghaiChina
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6
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Dimwamwa E, Pala A, Chundru V, Wright NC, Stanley GB. Dynamic corticothalamic modulation of the somatosensory thalamocortical circuit during wakefulness. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.18.549491. [PMID: 37503253 PMCID: PMC10370106 DOI: 10.1101/2023.07.18.549491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The feedback projections from cortical layer 6 (L6CT) to sensory thalamus have long been implicated in playing a primary role in gating sensory signaling but remain poorly understood. To causally elucidate the full range of effects of these projections, we targeted silicon probe recordings to the whisker thalamocortical circuit of awake mice selectively expressing Channelrhodopsin-2 in L6CT neurons. Through optogenetic manipulation of L6CT neurons, multi-site electrophysiological recordings, and modeling of L6CT circuitry, we establish L6CT neurons as dynamic modulators of ongoing spiking in the ventro-posterior-medial nucleus of thalamus (VPm), either suppressing or enhancing VPm spiking depending on L6CT neurons' firing rate and synchrony. Differential effects across the cortical excitatory and inhibitory sub-populations point to an overall influence of L6CT feedback on cortical excitability that could have profound implications for regulating sensory signaling across a range of ethologically relevant conditions.
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7
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Chau Loo Kung G, Knowles JK, Batra A, Ni L, Rosenberg J, McNab JA. Quantitative MRI reveals widespread, network-specific myelination change during generalized epilepsy progression. Neuroimage 2023; 280:120312. [PMID: 37574120 PMCID: PMC11095339 DOI: 10.1016/j.neuroimage.2023.120312] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/17/2023] [Accepted: 08/04/2023] [Indexed: 08/15/2023] Open
Abstract
Activity-dependent myelination is a fundamental mode of brain plasticity which significantly influences network function. We recently discovered that absence seizures, which occur in multiple forms of generalized epilepsy, can induce activity-dependent myelination, which in turn promotes further progression of epilepsy. Structural alterations of myelin are likely to be widespread, given that absence seizures arise from an extensive thalamocortical network involving frontoparietal regions of the bilateral hemispheres. However, the temporal course and spatial extent of myelin plasticity is unknown, due to limitations of gold-standard histological methods such as electron microscopy (EM). In this study, we leveraged magnetization transfer and diffusion MRI for estimation of g-ratios across major white matter tracts in a mouse model of generalized epilepsy with progressive absence seizures. EM was performed on the same brains after MRI. After seizure progression, we found increased myelination (decreased g-ratios) throughout the anterior portion (genu-to-body) of the corpus callosum but not in the posterior portion (body-splenium) nor in the fornix or the internal capsule. Curves obtained from averaging g-ratio values at every longitudinal point of the corpus callosum were statistically different with p<0.001. Seizure-associated myelin differences found in the corpus callosum body with MRI were statistically significant (p = 0.0027) and were concordant with EM in the same region (p = 0.01). Notably, these differences were not detected by diffusion tensor imaging. This study reveals widespread myelin structural change that is specific to the absence seizure network. Furthermore, our findings demonstrate the potential utility and importance of MRI-based g-ratio estimation to non-invasively detect myelin plasticity.
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Affiliation(s)
- Gustavo Chau Loo Kung
- Bioengineering Department, Stanford University, 443 Via Ortega, Stanford, CA 94305, United States; Radiology Department, Stanford University, 1201 Welch Rd, Stanford, CA 94305, United States.
| | - Juliet K Knowles
- Neurology Department, 1701 Page Mill Road, Palo Alto, CA 94304, United States.
| | - Ankita Batra
- Neurology Department, 1701 Page Mill Road, Palo Alto, CA 94304, United States.
| | - Lijun Ni
- Neurology Department, SIM1 G3035, Stanford, CA 94305, United States.
| | - Jarrett Rosenberg
- Radiology Department, Stanford University, 1201 Welch Rd, Stanford, CA 94305, United States.
| | - Jennifer A McNab
- Radiology Department, Stanford University, 1201 Welch Rd, Stanford, CA 94305, United States.
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8
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Rusina E, Simonti M, Duprat F, Cestèle S, Mantegazza M. Voltage-gated sodium channels in genetic epilepsy: up and down of excitability. J Neurochem 2023. [PMID: 37654020 DOI: 10.1111/jnc.15947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 08/11/2023] [Accepted: 08/13/2023] [Indexed: 09/02/2023]
Abstract
The past two decades have witnessed a wide range of studies investigating genetic variants of voltage-gated sodium (NaV ) channels, which are involved in a broad spectrum of diseases, including several types of epilepsy. We have reviewed here phenotypes and pathological mechanisms of genetic epilepsies caused by variants in NaV α and β subunits, as well as of some relevant interacting proteins (FGF12/FHF1, PRRT2, and Ankyrin-G). Notably, variants of all these genes can induce either gain- or loss-of-function of NaV leading to either neuronal hyperexcitability or hypoexcitability. We present the results of functional studies obtained with different experimental models, highlighting that they should be interpreted considering the features of the experimental system used. These systems are models, but they have allowed us to better understand pathophysiological issues, ameliorate diagnostics, orientate genetic counseling, and select/develop therapies within a precision medicine framework. These studies have also allowed us to gain insights into the physiological roles of different NaV channels and of the cells that express them. Overall, our review shows the progress that has been made, but also the need for further studies on aspects that have not yet been clarified. Finally, we conclude by highlighting some significant themes of general interest that can be gleaned from the results of the work of the last two decades.
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Affiliation(s)
- Evgeniia Rusina
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
| | - Martina Simonti
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
| | - Fabrice Duprat
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
- Inserm, Valbonne-Sophia Antipolis, France
| | - Sandrine Cestèle
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
| | - Massimo Mantegazza
- University Cote d'Azur, Valbonne-Sophia Antipolis, France
- CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne-Sophia Antipolis, France
- Inserm, Valbonne-Sophia Antipolis, France
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9
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Evans SW, Shi DQ, Chavarha M, Plitt MH, Taxidis J, Madruga B, Fan JL, Hwang FJ, van Keulen SC, Suomivuori CM, Pang MM, Su S, Lee S, Hao YA, Zhang G, Jiang D, Pradhan L, Roth RH, Liu Y, Dorian CC, Reese AL, Negrean A, Losonczy A, Makinson CD, Wang S, Clandinin TR, Dror RO, Ding JB, Ji N, Golshani P, Giocomo LM, Bi GQ, Lin MZ. A positively tuned voltage indicator for extended electrical recordings in the brain. Nat Methods 2023; 20:1104-1113. [PMID: 37429962 PMCID: PMC10627146 DOI: 10.1038/s41592-023-01913-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 05/15/2023] [Indexed: 07/12/2023]
Abstract
Genetically encoded voltage indicators (GEVIs) enable optical recording of electrical signals in the brain, providing subthreshold sensitivity and temporal resolution not possible with calcium indicators. However, one- and two-photon voltage imaging over prolonged periods with the same GEVI has not yet been demonstrated. Here, we report engineering of ASAP family GEVIs to enhance photostability by inversion of the fluorescence-voltage relationship. Two of the resulting GEVIs, ASAP4b and ASAP4e, respond to 100-mV depolarizations with ≥180% fluorescence increases, compared with the 50% fluorescence decrease of the parental ASAP3. With standard microscopy equipment, ASAP4e enables single-trial detection of spikes in mice over the course of minutes. Unlike GEVIs previously used for one-photon voltage recordings, ASAP4b and ASAP4e also perform well under two-photon illumination. By imaging voltage and calcium simultaneously, we show that ASAP4b and ASAP4e can identify place cells and detect voltage spikes with better temporal resolution than commonly used calcium indicators. Thus, ASAP4b and ASAP4e extend the capabilities of voltage imaging to standard one- and two-photon microscopes while improving the duration of voltage recordings.
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Affiliation(s)
- S Wenceslao Evans
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Dong-Qing Shi
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Mariya Chavarha
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Mark H Plitt
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Jiannis Taxidis
- Department of Neurology, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Blake Madruga
- Department of Neurology, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
| | - Jiang Lan Fan
- UC Berkeley/UCSF Joint Program in Bioengineering, University of California Berkeley, Berkeley, CA, USA
| | - Fuu-Jiun Hwang
- Department of Neurosurgery, Stanford University Medical Center, Stanford, CA, USA
| | - Siri C van Keulen
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | | | - Michelle M Pang
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Sharon Su
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Sungmoo Lee
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Yukun A Hao
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Guofeng Zhang
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Dongyun Jiang
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Lagnajeet Pradhan
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Richard H Roth
- Department of Neurosurgery, Stanford University Medical Center, Stanford, CA, USA
| | - Yu Liu
- Department of Neurosurgery, Stanford University Medical Center, Stanford, CA, USA
- Department of Ophthalmology, Stanford University Medical Center, Stanford, CA, USA
| | - Conor C Dorian
- Department of Neurology, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
| | - Austin L Reese
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
| | - Adrian Negrean
- Department of Neuroscience, Columbia University, New York, NY, USA
| | - Attila Losonczy
- Department of Neuroscience, Columbia University, New York, NY, USA
- Mortimer B. Zuckerman Mind Brain Behavior Institute, New York, NY, USA
- Kavli Institute for Brain Science, New York, NY, USA
| | - Christopher D Makinson
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
- Department of Neurology, Columbia University, New York, NY, USA
| | - Sui Wang
- Department of Ophthalmology, Stanford University Medical Center, Stanford, CA, USA
| | - Thomas R Clandinin
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Ron O Dror
- Department of Computer Science, Stanford University, Stanford, CA, USA
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, USA
| | - Jun B Ding
- Department of Neurosurgery, Stanford University Medical Center, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University Medical Center, Stanford, CA, USA
| | - Na Ji
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
- Department of Physics, University of California Berkeley, Berkeley, CA, USA
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Peyman Golshani
- Department of Neurology, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
- Semel Institute for Neuroscience and Human Behavior, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
| | - Lisa M Giocomo
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Guo-Qiang Bi
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Interdisciplinary Center for Brain Information, Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Michael Z Lin
- Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA.
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
- Department of Chemical and Systems Biology, Stanford University, Stanford, USA.
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10
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Zhao ET, Hull JM, Mintz Hemed N, Uluşan H, Bartram J, Zhang A, Wang P, Pham A, Ronchi S, Huguenard JR, Hierlemann A, Melosh NA. A CMOS-based highly scalable flexible neural electrode interface. SCIENCE ADVANCES 2023; 9:eadf9524. [PMID: 37285436 PMCID: PMC10246892 DOI: 10.1126/sciadv.adf9524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 05/03/2023] [Indexed: 06/09/2023]
Abstract
Perception, thoughts, and actions are encoded by the coordinated activity of large neuronal populations spread over large areas. However, existing electrophysiological devices are limited by their scalability in capturing this cortex-wide activity. Here, we developed an electrode connector based on an ultra-conformable thin-film electrode array that self-assembles onto silicon microelectrode arrays enabling multithousand channel counts at a millimeter scale. The interconnects are formed using microfabricated electrode pads suspended by thin support arms, termed Flex2Chip. Capillary-assisted assembly drives the pads to deform toward the chip surface, and van der Waals forces maintain this deformation, establishing Ohmic contact. Flex2Chip arrays successfully measured extracellular action potentials ex vivo and resolved micrometer scale seizure propagation trajectories in epileptic mice. We find that seizure dynamics in absence epilepsy in the Scn8a+/- model do not have constant propagation trajectories.
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Affiliation(s)
- Eric T. Zhao
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Jacob M. Hull
- Department of Neurology, Stanford University, Stanford, CA, USA
| | - Nofar Mintz Hemed
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Hasan Uluşan
- Department of Biosystems Engineering, ETH Zürich, Basel, Switzerland
| | - Julian Bartram
- Department of Biosystems Engineering, ETH Zürich, Basel, Switzerland
| | - Anqi Zhang
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Pingyu Wang
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Albert Pham
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Silvia Ronchi
- Department of Biosystems Engineering, ETH Zürich, Basel, Switzerland
| | | | | | - Nicholas A. Melosh
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
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11
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Lindquist BE, Timbie C, Voskobiynyk Y, Paz JT. Thalamocortical circuits in generalized epilepsy: Pathophysiologic mechanisms and therapeutic targets. Neurobiol Dis 2023; 181:106094. [PMID: 36990364 PMCID: PMC10192143 DOI: 10.1016/j.nbd.2023.106094] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/02/2023] [Accepted: 03/19/2023] [Indexed: 03/29/2023] Open
Abstract
Generalized epilepsy affects 24 million people globally; at least 25% of cases remain medically refractory. The thalamus, with widespread connections throughout the brain, plays a critical role in generalized epilepsy. The intrinsic properties of thalamic neurons and the synaptic connections between populations of neurons in the nucleus reticularis thalami and thalamocortical relay nuclei help generate different firing patterns that influence brain states. In particular, transitions from tonic firing to highly synchronized burst firing mode in thalamic neurons can cause seizures that rapidly generalize and cause altered awareness and unconsciousness. Here, we review the most recent advances in our understanding of how thalamic activity is regulated and discuss the gaps in our understanding of the mechanisms of generalized epilepsy syndromes. Elucidating the role of the thalamus in generalized epilepsy syndromes may lead to new opportunities to better treat pharmaco-resistant generalized epilepsy by thalamic modulation and dietary therapy.
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Affiliation(s)
- Britta E Lindquist
- UCSF Department of Neurology, Division of Neurocritical Care, United States of America; UCSF Department of Neurology, Division of Pediatric Epilepsy, United States of America; UCSF Department of Neurology, United States of America
| | - Clare Timbie
- Gladstone Institute of Neurological Disease, United States of America; UCSF Department of Neurology, Division of Pediatric Epilepsy, United States of America; UCSF Department of Neurology, United States of America
| | - Yuliya Voskobiynyk
- Gladstone Institute of Neurological Disease, United States of America; UCSF Department of Neurology, United States of America
| | - Jeanne T Paz
- Gladstone Institute of Neurological Disease, United States of America; UCSF Department of Neurology, United States of America; Kavli Institute for Fundamental Neuroscience, UCSF, United States of America.
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12
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Colombo S, Reddy HP, Petri S, Williams DJ, Shalomov B, Dhindsa RS, Gelfman S, Krizay D, Bera AK, Yang M, Peng Y, Makinson CD, Boland MJ, Frankel WN, Goldstein DB, Dascal N. Epilepsy in a mouse model of GNB1 encephalopathy arises from altered potassium (GIRK) channel signaling and is alleviated by a GIRK inhibitor. Front Cell Neurosci 2023; 17:1175895. [PMID: 37275776 PMCID: PMC10232839 DOI: 10.3389/fncel.2023.1175895] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/12/2023] [Indexed: 06/07/2023] Open
Abstract
De novo mutations in GNB1, encoding the Gβ1 subunit of G proteins, cause a neurodevelopmental disorder with global developmental delay and epilepsy, GNB1 encephalopathy. Here, we show that mice carrying a pathogenic mutation, K78R, recapitulate aspects of the disorder, including developmental delay and generalized seizures. Cultured mutant cortical neurons also display aberrant bursting activity on multi-electrode arrays. Strikingly, the antiepileptic drug ethosuximide (ETX) restores normal neuronal network behavior in vitro and suppresses spike-and-wave discharges (SWD) in vivo. ETX is a known blocker of T-type voltage-gated Ca2+ channels and G protein-coupled potassium (GIRK) channels. Accordingly, we present evidence that K78R results in a gain-of-function (GoF) effect by increasing the activation of GIRK channels in cultured neurons and a heterologous model (Xenopus oocytes)-an effect we show can be potently inhibited by ETX. This work implicates a GoF mechanism for GIRK channels in epilepsy, identifies a new mechanism of action for ETX in preventing seizures, and establishes this mouse model as a pre-clinical tool for translational research with predicative value for GNB1 encephalopathy.
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Affiliation(s)
- Sophie Colombo
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
| | - Haritha P. Reddy
- Department of Physiology and Pharmacology, School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
| | - Sabrina Petri
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
| | - Damian J. Williams
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
| | - Boris Shalomov
- Department of Physiology and Pharmacology, School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ryan S. Dhindsa
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
| | - Sahar Gelfman
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
| | - Daniel Krizay
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
| | - Amal K. Bera
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
| | - Mu Yang
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
- Mouse NeuroBehavior Core Facility, Columbia University Irving Medical Center, New York, NY, United States
| | - Yueqing Peng
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, United States
| | - Christopher D. Makinson
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
- Department of Neuroscience, Columbia University, New York, NY, United States
| | - Michael J. Boland
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
| | - Wayne N. Frankel
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY, United States
| | - David B. Goldstein
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY, United States
| | - Nathan Dascal
- Department of Physiology and Pharmacology, School of Medicine, Tel Aviv University, Tel Aviv, Israel
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13
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Ferguson B, Glick C, Huguenard JR. Prefrontal PV interneurons facilitate attention and are linked to attentional dysfunction in a mouse model of absence epilepsy. eLife 2023; 12:e78349. [PMID: 37014118 PMCID: PMC10072875 DOI: 10.7554/elife.78349] [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: 03/03/2022] [Accepted: 02/07/2023] [Indexed: 04/05/2023] Open
Abstract
Absence seizures are characterized by brief periods of unconsciousness accompanied by lapses in motor function that can occur hundreds of times throughout the day. Outside of these frequent moments of unconsciousness, approximately a third of people living with the disorder experience treatment-resistant attention impairments. Convergent evidence suggests prefrontal cortex (PFC) dysfunction may underlie attention impairments in affected patients. To examine this, we use a combination of slice physiology, fiber photometry, electrocorticography (ECoG), optogenetics, and behavior in the Scn8a+/-mouse model of absence epilepsy. Attention function was measured using a novel visual attention task where a light cue that varied in duration predicted the location of a food reward. In Scn8a+/-mice, we find altered parvalbumin interneuron (PVIN) output in the medial PFC (mPFC) in vitro and PVIN hypoactivity along with reductions in gamma power during cue presentation in vivo. This was associated with poorer attention performance in Scn8a+/-mice that could be rescued by gamma-frequency optogenetic stimulation of PVINs. This highlights cue-related PVIN activity as an important mechanism for attention and suggests PVINs may represent a therapeutic target for cognitive comorbidities in absence epilepsy.
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Affiliation(s)
- Brielle Ferguson
- Department of Neurology and Neurological Sciences, Stanford UniversityStanfordUnited States
- Department of Genetics, Harvard Medical SchoolBostonUnited States
- Program in Neurobiology and Department of Neurology, Boston Children's HospitalBostonUnited States
| | - Cameron Glick
- Department of Neurology and Neurological Sciences, Stanford UniversityStanfordUnited States
| | - John R Huguenard
- Department of Neurology and Neurological Sciences, Stanford UniversityStanfordUnited States
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14
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Thalamic control of sensory processing and spindles in a biophysical somatosensory thalamoreticular circuit model of wakefulness and sleep. Cell Rep 2023; 42:112200. [PMID: 36867532 PMCID: PMC10066598 DOI: 10.1016/j.celrep.2023.112200] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 01/04/2023] [Accepted: 02/15/2023] [Indexed: 03/04/2023] Open
Abstract
Thalamoreticular circuitry plays a key role in arousal, attention, cognition, and sleep spindles, and is linked to several brain disorders. A detailed computational model of mouse somatosensory thalamus and thalamic reticular nucleus has been developed to capture the properties of over 14,000 neurons connected by 6 million synapses. The model recreates the biological connectivity of these neurons, and simulations of the model reproduce multiple experimental findings in different brain states. The model shows that inhibitory rebound produces frequency-selective enhancement of thalamic responses during wakefulness. We find that thalamic interactions are responsible for the characteristic waxing and waning of spindle oscillations. In addition, we find that changes in thalamic excitability control spindle frequency and their incidence. The model is made openly available to provide a new tool for studying the function and dysfunction of the thalamoreticular circuitry in various brain states.
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15
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Structure of human Na V1.6 channel reveals Na + selectivity and pore blockade by 4,9-anhydro-tetrodotoxin. Nat Commun 2023; 14:1030. [PMID: 36823201 PMCID: PMC9950489 DOI: 10.1038/s41467-023-36766-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 02/15/2023] [Indexed: 02/25/2023] Open
Abstract
The sodium channel NaV1.6 is widely expressed in neurons of the central and peripheral nervous systems, which plays a critical role in regulating neuronal excitability. Dysfunction of NaV1.6 has been linked to epileptic encephalopathy, intellectual disability and movement disorders. Here we present cryo-EM structures of human NaV1.6/β1/β2 alone and complexed with a guanidinium neurotoxin 4,9-anhydro-tetrodotoxin (4,9-ah-TTX), revealing molecular mechanism of NaV1.6 inhibition by the blocker. The apo-form structure reveals two potential Na+ binding sites within the selectivity filter, suggesting a possible mechanism for Na+ selectivity and conductance. In the 4,9-ah-TTX bound structure, 4,9-ah-TTX binds to a pocket similar to the tetrodotoxin (TTX) binding site, which occupies the Na+ binding sites and completely blocks the channel. Molecular dynamics simulation results show that subtle conformational differences in the selectivity filter affect the affinity of TTX analogues. Taken together, our results provide important insights into NaV1.6 structure, ion conductance, and inhibition.
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16
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Sun S, Wang H. Clocking Epilepsies: A Chronomodulated Strategy-Based Therapy for Rhythmic Seizures. Int J Mol Sci 2023; 24:ijms24044223. [PMID: 36835631 PMCID: PMC9962262 DOI: 10.3390/ijms24044223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/08/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Epilepsy is a neurological disorder characterized by hypersynchronous recurrent neuronal activities and seizures, as well as loss of muscular control and sometimes awareness. Clinically, seizures have been reported to display daily variations. Conversely, circadian misalignment and circadian clock gene variants contribute to epileptic pathogenesis. Elucidation of the genetic bases of epilepsy is of great importance because the genetic variability of the patients affects the efficacies of antiepileptic drugs (AEDs). For this narrative review, we compiled 661 epilepsy-related genes from the PHGKB and OMIM databases and classified them into 3 groups: driver genes, passenger genes, and undetermined genes. We discuss the potential roles of some epilepsy driver genes based on GO and KEGG analyses, the circadian rhythmicity of human and animal epilepsies, and the mutual effects between epilepsy and sleep. We review the advantages and challenges of rodents and zebrafish as animal models for epileptic studies. Finally, we posit chronomodulated strategy-based chronotherapy for rhythmic epilepsies, integrating several lines of investigation for unraveling circadian mechanisms underpinning epileptogenesis, chronopharmacokinetic and chronopharmacodynamic examinations of AEDs, as well as mathematical/computational modeling to help develop time-of-day-specific AED dosing schedules for rhythmic epilepsy patients.
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Affiliation(s)
- Sha Sun
- Center for Circadian Clocks, Soochow University, Suzhou 215123, China
- School of Biology and Basic Medical Sciences, Suzhou Medical College, Soochow University, Suzhou 215123, China
| | - Han Wang
- Center for Circadian Clocks, Soochow University, Suzhou 215123, China
- School of Biology and Basic Medical Sciences, Suzhou Medical College, Soochow University, Suzhou 215123, China
- Correspondence: or ; Tel.: +86-186-0512-8971
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17
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Zheng B, Liu DD, Theyel BB, Abdulrazeq H, Kimata AR, Lauro PM, Asaad WF. Thalamic neuromodulation in epilepsy: A primer for emerging circuit-based therapies. Expert Rev Neurother 2023; 23:123-140. [PMID: 36731858 DOI: 10.1080/14737175.2023.2176752] [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: 02/04/2023]
Abstract
INTRODUCTION Epilepsy is a common, often debilitating disease of hyperexcitable neural networks. While medically intractable cases may benefit from surgery, there may be no single, well-localized focus for resection or ablation. In such cases, approaching the disease from a network-based perspective may be beneficial. AREAS COVERED Herein, the authors provide a narrative review of normal thalamic anatomy and physiology and propose general strategies for preventing and/or aborting seizures by modulating this structure. Additionally, they make specific recommendations for targeting the thalamus within different contexts, motivated by a more detailed discussion of its distinct nuclei and their respective connectivity. By describing important principles governing thalamic function and its involvement in seizure networks, the authors aim to provide a primer for those now entering this fast-growing field of thalamic neuromodulation for epilepsy. EXPERT OPINION The thalamus is critically involved with the function of many cortical and subcortical areas, suggesting it may serve as a compelling node for preventing or aborting seizures, and so it has increasingly been targeted for the surgical treatment of epilepsy. As various thalamic neuromodulation strategies for seizure control are developed, there is a need to ground such interventions in a mechanistic, circuit-based framework.
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Affiliation(s)
- Bryan Zheng
- The Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neurosurgery, Rhode Island Hospital, Providence, RI, USA
| | - David D Liu
- The Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Brian B Theyel
- Department of Psychiatry, Rhode Island Hospital, Providence, RI, USA.,Department of Neuroscience, Brown University, Providence, RI, USA
| | - Hael Abdulrazeq
- Department of Neurosurgery, Rhode Island Hospital, Providence, RI, USA
| | - Anna R Kimata
- The Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neurosurgery, Rhode Island Hospital, Providence, RI, USA
| | - Peter M Lauro
- The Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neuroscience, Brown University, Providence, RI, USA
| | - Wael F Asaad
- Department of Neurosurgery, Rhode Island Hospital, Providence, RI, USA.,Department of Neuroscience, Brown University, Providence, RI, USA.,The Carney Institute for Brain Science, Brown University, Providence, RI, USA.,The Norman Prince Neurosciences Institute, Rhode Island Hospital, Providence, RI, USA
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18
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Dudarenko MV, Pozdnyakova NG. Perinatal hypoxia and thalamus brain region: increased efficiency of antiepileptic drug levetiracetam to inhibit GABA release from nerve terminals. UKRAINIAN BIOCHEMICAL JOURNAL 2022. [DOI: 10.15407/ubj94.05.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Levetiracetam (LV), 2S-(2-oxo-1-pyrrolidiny1) butanamide, is an antiepileptic drug. The exact mechanisms of anticonvulsant effects of LV remain unclear. In this study, rats (Wistar strain) underwent hypoxia and seizures at the age of 10–12 postnatal days (pd). [3H]GABA release was analysed in isolated from thalamus nerve terminals (synaptosomes) during development at the age of pd 17–19 and pd 24–26 (infantile stage), pd 38–40 (puberty) and pd 66–73 (young adults) in control and after perinatal hypoxia. The extracellular level of [3H]GABA in the preparation of thalamic synaptosomes increased during development at the age of pd 38–40 and pd 66–73 as compared to earlier ones. LV did not influence the extracellular level of [3H]GABA in control and after perinatal hypoxia at all studied ages. Exocytotic [3H]GABA release in control increased at the age of pd 24–26 as compared to pd 17–19. After hypoxia, exocytotic [3H]GABA release from synaptosomes also increased during development. LV elevated [3H]GABA release from thalamic synaptosomes at the age of pd 66–73 after hypoxia and during blockage of GABA uptake by NO-711 only. LV realizes its antiepileptic effects at the presynaptic site through an increase in exocytotic release of [3H]GABA in thalamic synaptosomes after perinatal hypoxia at pd 66–73. LV exhibited a more significant effect in thalamic synaptosomes after perinatal hypoxia than in control ones. The action of LV is age-dependent, and the drug was inert at the infantile stage that can be useful for an LV application strategy in child epilepsy therapy. Keywords: brain development, exocytosis, GABA, levetiracetam, perinatal hypoxia, thalamic synaptosomes
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19
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Abstract
Recent advances in genomics have revealed a wide spectrum of genetic variants associated with neurodevelopmental disorders at an unprecedented scale. An increasing number of studies have consistently identified mutations-both inherited and de novo-impacting the function of specific brain circuits. This suggests that, during brain development, alterations in distinct neural circuits, cell types, or broad regulatory pathways ultimately shaping synapses might be a dysfunctional process underlying these disorders. Here, we review findings from human studies and animal model research to provide a comprehensive description of synaptic and circuit mechanisms implicated in neurodevelopmental disorders. We discuss how specific synaptic connections might be commonly disrupted in different disorders and the alterations in cognition and behaviors emerging from imbalances in neuronal circuits. Moreover, we review new approaches that have been shown to restore or mitigate dysfunctional processes during specific critical windows of brain development. Considering the heterogeneity of neurodevelopmental disorders, we also highlight the recent progress in developing improved clinical biomarkers and strategies that will help to identify novel therapeutic compounds and opportunities for early intervention.
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Affiliation(s)
- David Exposito-Alonso
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom;
- Current affiliation: Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA;
| | - Beatriz Rico
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom;
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20
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Moretti J, Terstege DJ, Poh EZ, Epp JR, Rodger J. Low intensity repetitive transcranial magnetic stimulation modulates brain-wide functional connectivity to promote anti-correlated c-Fos expression. Sci Rep 2022; 12:20571. [PMID: 36446821 PMCID: PMC9708643 DOI: 10.1038/s41598-022-24934-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/22/2022] [Indexed: 11/30/2022] Open
Abstract
Repetitive transcranial magnetic stimulation (rTMS) induces action potentials to induce plastic changes in the brain with increasing evidence for the therapeutic importance of brain-wide functional network effects of rTMS; however, the influence of sub-action potential threshold (low-intensity; LI-) rTMS on neuronal activity is largely unknown. We investigated whether LI-rTMS modulates neuronal activity and functional connectivity and also specifically assessed modulation of parvalbumin interneuron activity. We conducted a brain-wide analysis of c-Fos, a marker for neuronal activity, in mice that received LI-rTMS to visual cortex. Mice received single or multiple sessions of excitatory 10 Hz LI-rTMS with custom rodent coils or were sham controls. We assessed changes to c-Fos positive cell densities and c-Fos/parvalbumin co-expression. Peak c-Fos expression corresponded with activity during rTMS. We also assessed functional connectivity changes using brain-wide c-Fos-based network analysis. LI-rTMS modulated c-Fos expression in cortical and subcortical regions. c-Fos density changes were most prevalent with acute stimulation, however chronic stimulation decreased parvalbumin interneuron activity, most prominently in the amygdala and striatum. LI-rTMS also increased anti-correlated functional connectivity, with the most prominent effects also in the amygdala and striatum following chronic stimulation. LI-rTMS induces changes in c-Fos expression that suggest modulation of neuronal activity and functional connectivity throughout the brain. Our results suggest that LI-rTMS promotes anticorrelated functional connectivity, possibly due to decreased parvalbumin interneuron activation induced by chronic stimulation. These changes may underpin therapeutic rTMS effects, therefore modulation of subcortical activity supports rTMS for treatment of disorders involving subcortical dysregulation.
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Affiliation(s)
- Jessica Moretti
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia.
- Perron Institute for Neurological and Translational Science, Perth, WA, Australia.
| | - Dylan J Terstege
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Eugenia Z Poh
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
- Perron Institute for Neurological and Translational Science, Perth, WA, Australia
- Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
| | - Jonathan R Epp
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Jennifer Rodger
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia.
- Perron Institute for Neurological and Translational Science, Perth, WA, Australia.
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21
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Emx1-Cre Is Expressed in Peripheral Autonomic Ganglia That Regulate Central Cardiorespiratory Functions. eNeuro 2022; 9:ENEURO.0093-22.2022. [PMID: 36192157 PMCID: PMC9581573 DOI: 10.1523/eneuro.0093-22.2022] [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: 02/24/2022] [Revised: 08/02/2022] [Accepted: 08/05/2022] [Indexed: 12/15/2022] Open
Abstract
The Emx1-IRES-Cre transgenic mouse is commonly used to direct genetic recombination in forebrain excitatory neurons. However, the original study reported that Emx1-Cre is also expressed embryonically in peripheral autonomic ganglia, which could potentially affect the interpretation of targeted circuitry contributing to systemic phenotypes. Here, we report that Emx1-Cre is expressed in the afferent vagus nerve system involved in autonomic cardiorespiratory regulatory pathways. Our imaging studies revealed expression of Emx1-Cre driven tdtomato fluorescence in the afferent vagus nerve innervating the dorsal medulla of brainstem, cell bodies in the nodose ganglion, and their potential target structures at the carotid bifurcation such as the carotid sinus and the superior cervical ganglion (SCG). Photostimulation of the afferent terminals in the nucleus tractus solitarius (NTS) in vitro using Emx1-Cre driven ChR2 reliably evoked EPSCs in the postsynaptic neurons with electrophysiological characteristics consistent with the vagus afferent nerves. In addition, optogenetic stimulation targeting the Emx1-Cre expressing structures identified in this study, such as vagus nerve, carotid bifurcation, and the dorsal medulla surface transiently depressed cardiorespiratory rate in urethane anesthetized mice in vivo Together, our study demonstrates that Emx1-IRES-Cre is expressed in the key peripheral autonomic nerve system and can modulate cardiorespiratory function independently of forebrain expression. These results raise caution when interpreting systemic phenotypes of Emx1-IRES-Cre conditional recombinant mice, and also suggest the utility of this line to investigate modulators of the afferent vagal system.
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Miralles R, Patel MK. That’s a Wrap: Could Controlling Activity-Regulated Myelination Prevent Absence Seizures? Epilepsy Curr 2022; 22:395-397. [DOI: 10.1177/15357597221123898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
[Box: see text]
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Affiliation(s)
- Raquel Miralles
- University of Virginia Health System Ringgold Standard Institution–Anesthesiology, Charlottesville, VA, USA
| | - Manoj K. Patel
- University of Virginia Health System Ringgold Standard Institution–Anesthesiology, Charlottesville, VA, USA
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Johannesen KM, Liu Y, Koko M, Gjerulfsen CE, Sonnenberg L, Schubert J, Fenger CD, Eltokhi A, Rannap M, Koch NA, Lauxmann S, Krüger J, Kegele J, Canafoglia L, Franceschetti S, Mayer T, Rebstock J, Zacher P, Ruf S, Alber M, Sterbova K, Lassuthová P, Vlckova M, Lemke JR, Platzer K, Krey I, Heine C, Wieczorek D, Kroell-Seger J, Lund C, Klein KM, Au PYB, Rho JM, Ho AW, Masnada S, Veggiotti P, Giordano L, Accorsi P, Hoei-Hansen CE, Striano P, Zara F, Verhelst H, Verhoeven JS, Braakman HMH, van der Zwaag B, Harder AVE, Brilstra E, Pendziwiat M, Lebon S, Vaccarezza M, Le NM, Christensen J, Grønborg S, Scherer SW, Howe J, Fazeli W, Howell KB, Leventer R, Stutterd C, Walsh S, Gerard M, Gerard B, Matricardi S, Bonardi CM, Sartori S, Berger A, Hoffman-Zacharska D, Mastrangelo M, Darra F, Vøllo A, Motazacker MM, Lakeman P, Nizon M, Betzler C, Altuzarra C, Caume R, Roubertie A, Gélisse P, Marini C, Guerrini R, Bilan F, Tibussek D, Koch-Hogrebe M, Perry MS, Ichikawa S, Dadali E, Sharkov A, Mishina I, Abramov M, Kanivets I, Korostelev S, Kutsev S, Wain KE, Eisenhauer N, Wagner M, Savatt JM, Müller-Schlüter K, Bassan H, Borovikov A, Nassogne MC, Destrée A, Schoonjans AS, Meuwissen M, Buzatu M, Jansen A, Scalais E, Srivastava S, Tan WH, Olson HE, Loddenkemper T, Poduri A, Helbig KL, Helbig I, Fitzgerald MP, Goldberg EM, Roser T, Borggraefe I, Brünger T, May P, Lal D, Lederer D, Rubboli G, Heyne HO, Lesca G, Hedrich UBS, Benda J, Gardella E, Lerche H, Møller RS. Genotype-phenotype correlations in SCN8A-related disorders reveal prognostic and therapeutic implications. Brain 2022; 145:2991-3009. [PMID: 34431999 PMCID: PMC10147326 DOI: 10.1093/brain/awab321] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/24/2021] [Accepted: 07/22/2021] [Indexed: 11/13/2022] Open
Abstract
We report detailed functional analyses and genotype-phenotype correlations in 392 individuals carrying disease-causing variants in SCN8A, encoding the voltage-gated Na+ channel Nav1.6, with the aim of describing clinical phenotypes related to functional effects. Six different clinical subgroups were identified: Group 1, benign familial infantile epilepsy (n = 15, normal cognition, treatable seizures); Group 2, intermediate epilepsy (n = 33, mild intellectual disability, partially pharmaco-responsive); Group 3, developmental and epileptic encephalopathy (n = 177, severe intellectual disability, majority pharmaco-resistant); Group 4, generalized epilepsy (n = 20, mild to moderate intellectual disability, frequently with absence seizures); Group 5, unclassifiable epilepsy (n = 127); and Group 6, neurodevelopmental disorder without epilepsy (n = 20, mild to moderate intellectual disability). Those in Groups 1-3 presented with focal or multifocal seizures (median age of onset: 4 months) and focal epileptiform discharges, whereas the onset of seizures in patients with generalized epilepsy was later (median: 42 months) with generalized epileptiform discharges. We performed functional studies expressing missense variants in ND7/23 neuroblastoma cells and primary neuronal cultures using recombinant tetrodotoxin-insensitive human Nav1.6 channels and whole-cell patch-clamping. Two variants causing developmental and epileptic encephalopathy showed a strong gain-of-function (hyperpolarizing shift of steady-state activation, strongly increased neuronal firing rate) and one variant causing benign familial infantile epilepsy or intermediate epilepsy showed a mild gain-of-function (defective fast inactivation, less increased firing). In contrast, all three variants causing generalized epilepsy induced a loss-of-function (reduced current amplitudes, depolarizing shift of steady-state activation, reduced neuronal firing). Functional effects were known for 170 individuals. All 136 individuals carrying a functionally tested gain-of-function variant had either focal (n = 97, Groups 1-3) or unclassifiable (n = 39) epilepsy, whereas 34 individuals with a loss-of-function variant had either generalized (n = 14), no (n = 11) or unclassifiable (n = 6) epilepsy; only three had developmental and epileptic encephalopathy. Computational modelling in the gain-of-function group revealed a significant correlation between the severity of the electrophysiological and clinical phenotypes. Gain-of-function variant carriers responded significantly better to sodium channel blockers than to other anti-seizure medications, and the same applied for all individuals in Groups 1-3. In conclusion, our data reveal clear genotype-phenotype correlations between age at seizure onset, type of epilepsy and gain- or loss-of-function effects of SCN8A variants. Generalized epilepsy with absence seizures is the main epilepsy phenotype of loss-of-function variant carriers and the extent of the electrophysiological dysfunction of the gain-of-function variants is a main determinant of the severity of the clinical phenotype in focal epilepsies. Our pharmacological data indicate that sodium channel blockers present a treatment option in SCN8A-related focal epilepsy with onset in the first year of life.
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Affiliation(s)
- Katrine M Johannesen
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Center, 4293 Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, 5230 Odense, Denmark
| | - Yuanyuan Liu
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Mahmoud Koko
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Cathrine E Gjerulfsen
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Center, 4293 Dianalund, Denmark
| | - Lukas Sonnenberg
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
- Institute for Neurobiology, University of Tuebingen, 72072 Tuebingen, Germany
| | - Julian Schubert
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Christina D Fenger
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Center, 4293 Dianalund, Denmark
| | - Ahmed Eltokhi
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Maert Rannap
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Nils A Koch
- Institute for Neurobiology, University of Tuebingen, 72072 Tuebingen, Germany
| | - Stephan Lauxmann
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
- Institute for Neurobiology, University of Tuebingen, 72072 Tuebingen, Germany
| | - Johanna Krüger
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Josua Kegele
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Laura Canafoglia
- Department of Diagnostics and Technology, Fondazione IRCCS Istituto Neurologio Carlo Besta, 20125 Milan, Italy
| | - Silvana Franceschetti
- Department of Diagnostics and Technology, Fondazione IRCCS Istituto Neurologio Carlo Besta, 20125 Milan, Italy
| | - Thomas Mayer
- Epilepsy Center Kleinwachau, 01454 Dresden-Radeberg, Germany
| | | | - Pia Zacher
- Epilepsy Center Kleinwachau, 01454 Dresden-Radeberg, Germany
| | - Susanne Ruf
- Department of Pediatric Neurology and Developmental Medicine, University Children’s Hospital, 72072 Tuebingen, Germany
| | - Michael Alber
- Department of Pediatric Neurology and Developmental Medicine, University Children’s Hospital, 72072 Tuebingen, Germany
| | - Katalin Sterbova
- Department of Child Neurology, 2nd Faculty of Medicine, Charles University and University Hospital Motol, 10000 Prague, Czech Republic
| | - Petra Lassuthová
- Department of Child Neurology, 2nd Faculty of Medicine, Charles University and University Hospital Motol, 10000 Prague, Czech Republic
| | - Marketa Vlckova
- Department of Child Neurology, 2nd Faculty of Medicine, Charles University and University Hospital Motol, 10000 Prague, Czech Republic
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, 4275 Leipzig, Germany
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, 4275 Leipzig, Germany
| | - Ilona Krey
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, 4275 Leipzig, Germany
| | - Constanze Heine
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, 4275 Leipzig, Germany
| | - Dagmar Wieczorek
- Institute of Human Genetics, University Clinic, Heinrich-Heine-University, 40210 Düsseldorf, Germany
| | - Judith Kroell-Seger
- Children’s Department, Swiss Epilepsy Centre, Clinic Lengg, 8001 Zurich, Switzerland
| | - Caroline Lund
- National Centre for Rare Epilepsy-Related Disorders, Oslo University Hospital, 0001 Oslo, Norway
| | - Karl Martin Klein
- Departments of Clinical Neurosciences, Medical Genetics and Community Health Sciences, Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2P 0A1, Canada
| | - P Y Billie Au
- Department of Medical Genetics, Alberta Children’s Hospital Research Institute, University of Calgary, AB T6G 2T4, Canada
| | - Jong M Rho
- Section of Pediatric Neurology, Alberta Children’s Hospital, Cumming School of Medicine, University of Calgary, Calgary, AB T2P 0A1, Canada
| | - Alice W Ho
- Section of Pediatric Neurology, Alberta Children’s Hospital, Cumming School of Medicine, University of Calgary, Calgary, AB T2P 0A1, Canada
| | - Silvia Masnada
- Department of Child Neurology, V. Buzzi Children’s Hospital, 20125 Milan, Italy
| | - Pierangelo Veggiotti
- Department of Child Neurology, V. Buzzi Children’s Hospital, 20125 Milan, Italy
- ‘L. Sacco’ Department of Biomedical and Clinical Sciences, University of Milan, 20157 Milan, Italy
| | - Lucio Giordano
- Child Neuropsychiatric Unit, Civilian Hospital, 25100 Brescia, Italy
| | - Patrizia Accorsi
- Child Neuropsychiatric Unit, Civilian Hospital, 25100 Brescia, Italy
| | - Christina E Hoei-Hansen
- Department of Pediatrics, Copenhagen University Hospital Rigshospitalet, 2200 Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16121 Genova, Italy
- IRCCS ‘G. Gaslini’ Institute, 16121 Genoa, Italy
| | | | - Helene Verhelst
- Department of Pediatrics, Division of Pediatric Neurology, Gent University Hospital, 9042 Gent, Belgium
| | - Judith S Verhoeven
- Academic Center for Epileptology, Kempenhaeghe/Maastricht University Medical Center, 5591 Heeze, The Netherlands
| | - Hilde M H Braakman
- Department of Pediatric Neurology, Amalia Children’s Hospital, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Bert van der Zwaag
- Department of Genetics, University Medical Center Utrecht, Utrecht University, 3553 Utrecht, The Netherlands
| | - Aster V E Harder
- Department of Genetics, University Medical Center Utrecht, Utrecht University, 3553 Utrecht, The Netherlands
| | - Eva Brilstra
- Department of Genetics, University Medical Center Utrecht, Utrecht University, 3553 Utrecht, The Netherlands
| | - Manuela Pendziwiat
- Department of Neuropediatrics, Universitätsklinikum Schleswig Holstein Campus Kiel, 24106 Kiel, Germany
| | - Sebastian Lebon
- Pediatric Neurology and Neurorehabilitation Unit, Woman Mother Child Department, Lausanne University Hospital (CHUV), 1000 Lausanne, Switzerland
- University of Lausanne, 1000 Lausanne, Switzerland
| | - Maria Vaccarezza
- Department of Pediatric Neurology, Hospital Italiano de Buenos Aires, C1428 Buenos Aires, Argentina
| | - Ngoc Minh Le
- Center for Pediatric Neurology, Cleveland Clinic, Cleveland, OH 44102, USA
| | - Jakob Christensen
- Department of Neurology, Aarhus University Hospital, 8000 Aarhus, Denmark
| | - Sabine Grønborg
- Center for Rare Diseases, Department of Pediatrics and Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, 2200 Copenhagen, Denmark
| | - Stephen W Scherer
- McLaughlin Centre and Department of Molecular Genetics, University of Toronto, Toronto, ON 66777, Canada
- The Centre for Applied Genomics and Department of Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON 66777, Canada
| | - Jennifer Howe
- Department of Neuropediatrics, University Hospital Bonn, 53229 Bonn, Germany
| | - Walid Fazeli
- Institute for Molecular and Behavioral Neuroscience, University of Cologne, 50667 Cologne, Germany
- Neurology Department, The Royal Children’s Hospital Melbourne, 3002 Melbourne, Australia
| | - Katherine B Howell
- Neurology Department, The Royal Children’s Hospital Melbourne, 3002 Melbourne, Australia
- Murdoch Children’s Research Institute, 3052 Parkville, Australia
- Department of Pediatrics, University of Melbourne, Royal Children’s Hospital, 3052 Parkville, Australia
| | - Richard Leventer
- Neurology Department, The Royal Children’s Hospital Melbourne, 3002 Melbourne, Australia
- Murdoch Children’s Research Institute, 3052 Parkville, Australia
- Department of Pediatrics, University of Melbourne, Royal Children’s Hospital, 3052 Parkville, Australia
| | - Chloe Stutterd
- Murdoch Children’s Research Institute, 3052 Parkville, Australia
- Department of Pediatrics, University of Melbourne, Royal Children’s Hospital, 3052 Parkville, Australia
| | - Sonja Walsh
- Department of Neuropediatrics, Children’s Hospital, University Hospital Carl Gustav Carus, Technical University, 1099 Dresden, Germany
| | - Marion Gerard
- Genetics Department, CHU Côte de Nacre, 14118 Caen, France
| | | | - Sara Matricardi
- Child Neurology and Psychiatry Unit, Children’s Hospital G. Salesi, 60121 Ancona, Italy
| | - Claudia M Bonardi
- Department of Woman’s and Child’s Health, Padova University Hospital, 35100 Padova, Italy
| | - Stefano Sartori
- Child Neurology and Clinical Neurophysiology Unit, Padova University Hospital, 35100 Padova, Italy
| | - Andrea Berger
- Department of Neuropediatrics, Klinikum Weiden, Kliniken Nordoberpfalz AG, 92637 Weiden, Germany
| | | | - Massimo Mastrangelo
- Pediatric Neurology Unit, Vittore Buzzi Hospital, ASST Fatebenefratelli Sacco, 20100 Milan, Italy
| | - Francesca Darra
- Department of Surgical Sciences, Dentistry, Gynecology and Pediatrics, University of Verona, 37121 Verona, Italy
| | - Arve Vøllo
- Department of Pediatrics, Oestfold Hospital, 1712 Graalum, Norway
| | - M Mahdi Motazacker
- Laboratory of Genome Diagnostics, Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, 1019 Amsterdam, Netherlands
| | - Phillis Lakeman
- Department of Clinical Genetics, Amsterdam Reproduction and Development Research Institute, Amsterdam UMC, University of Amsterdam, 1019 Amsterdam, Netherlands
| | - Mathilde Nizon
- Service de Génétique Médicale, CHU Nantes, 44093 Nantes, France
| | - Cornelia Betzler
- Clinic for Neuropediatrics and Neurorehabilitation, Epilepsy Center for Children and Adolescents, Schön Klinik, 83569 Vogtareuth, Germany
- Research Institute ‘Rehabilitation, Transition, Palliation’, PMU Salzburg, 5020 Salzburg, Austria
| | - Cecilia Altuzarra
- Department of Pediatrics, St. Jacques Hospital, 25000 Besançon, France
| | - Roseline Caume
- Clinique de Génétique Guy Fontaine, CHU Lille, 59000, Lille, France
| | - Agathe Roubertie
- Département de Neuropédiatrie, INSERM, CHU Montpellier, 34000 Montpellier, France
| | - Philippe Gélisse
- Département de Neuropédiatrie, INSERM, CHU Montpellier, 34000 Montpellier, France
| | - Carla Marini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children’s Hospital, University of Florence, 50131 Florence, Italy
| | | | - Frederic Bilan
- Service de Génétique, Centre Hospitalier Universitaire de Poitiers, 86021 Poitiers, France
| | - Daniel Tibussek
- Child Neurology, Center for Pediatric and Teenage Health Care, 53757 Sankt Augustin, Germany
| | | | - M Scott Perry
- Justin Neurosciences Center, Cook Children’s Medical Center, Fort Worth, TX 76101, USA
| | - Shoji Ichikawa
- Department of Clinical Diagnostics, Ambry Genetics, Aliso Viejo, CA 92637, USA
| | - Elena Dadali
- Research Centre for Medical Genetics, 115522 Moscow, Russia
- Veltischev Research and Clinical Institute for Pediatrics, Pirogov Russian National Research Medical University, 125412 Moscow, Russia
| | - Artem Sharkov
- Veltischev Research and Clinical Institute for Pediatrics, Pirogov Russian National Research Medical University, 125412 Moscow, Russia
- Genomed Ltd., 100000 Moscow, Russia
| | - Irina Mishina
- Research Centre for Medical Genetics, 115522 Moscow, Russia
| | - Mikhail Abramov
- Veltischev Research and Clinical Institute for Pediatrics, Pirogov Russian National Research Medical University, 125412 Moscow, Russia
| | - Ilya Kanivets
- Svt. Luka’s Institute of Child Neurology & Epilepsy, 100000 Moscow, Russia
- Russian Medical Academy of Continuous Professional Education, 100000 Moscow, Russia
| | - Sergey Korostelev
- Svt. Luka’s Institute of Child Neurology & Epilepsy, 100000 Moscow, Russia
- I.M. Sechenov First Moscow State Medical University, 100000 Moscow, Russia
| | - Sergey Kutsev
- Research Centre for Medical Genetics, 115522 Moscow, Russia
| | - Karen E Wain
- Geisinger Autism & Developmental Medicine Institute, Lewisburg, PA 17837, USA
| | - Nancy Eisenhauer
- Geisinger Autism & Developmental Medicine Institute, Lewisburg, PA 17837, USA
| | - Monisa Wagner
- Geisinger Autism & Developmental Medicine Institute, Lewisburg, PA 17837, USA
| | - Juliann M Savatt
- Geisinger Autism & Developmental Medicine Institute, Lewisburg, PA 17837, USA
| | - Karen Müller-Schlüter
- Epilepsy Center for Children, University Hospital Neuruppin, Brandenburg Medical School, 16816 Neuruppin, Germany
| | - Haim Bassan
- Pediatric Neurology & Development Center, Shamir Medical Center (Assaf Harofe), Be'er Ya'akov, Israel
- Sackler Faculty of Medicine, Tel Aviv University, 5296001 Tel Aviv, Israel
| | | | - Marie Cecile Nassogne
- Pediatric Neurology Unit, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, 1000 Brussels, Belgium
| | - Anne Destrée
- Institute for Pathology and Genetics, 6040 Gosselies, Belgium
| | - An Sofie Schoonjans
- Department of Pediatrics and Pediatric Neurology, Antwerp University Hospital, University of Antwerp, 2650 Edegem, Belgium
| | - Marije Meuwissen
- Pediatric Neurology, Marie Curie Hospital—CHU Charleroi, 6032 Charleroi, Belgium
| | - Marga Buzatu
- Pediatric Neurology, Marie Curie Hospital—CHU Charleroi, 6032 Charleroi, Belgium
| | - Anna Jansen
- Pediatric Neurology Unit, Department of Pediatrics, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Emmanuel Scalais
- Pediatric Neurology Unit, Department of Pediatrics, Centre Hospitalier de Luxembourg, 1313 Luxembourg, Luxembourg
| | - Siddharth Srivastava
- Department of Neurology, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02108, USA
| | - Wen Hann Tan
- Department of Genetics, Boston Children’s Hospital, Boston, MA 02108, USA
| | - Heather E Olson
- Department of Neurology, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02108, USA
- Epilepsy Genetics Program, Boston Children’s Hospital, Boston, MA 02108, USA
| | - Tobias Loddenkemper
- Department of Neurology, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02108, USA
| | - Annapurna Poduri
- Department of Neurology, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02108, USA
- Epilepsy Genetics Program, Boston Children’s Hospital, Boston, MA 02108, USA
| | - Katherine L Helbig
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- The Epilepsy Neurogenetics Initiative (ENGIN), Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Ingo Helbig
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- The Epilepsy Neurogenetics Initiative (ENGIN), Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Biomedical and Health Informatics (DBHi), Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
- Institute of Clinical Molecular Biology, Kiel University, 24105 Kiel, Germany
- Department of Neuropediatrics, Kiel University, 24105 Kiel, Germany
| | - Mark P Fitzgerald
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- The Epilepsy Neurogenetics Initiative (ENGIN), Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Biomedical and Health Informatics (DBHi), Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Institute of Clinical Molecular Biology, Kiel University, 24105 Kiel, Germany
| | - Ethan M Goldberg
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- The Epilepsy Neurogenetics Initiative (ENGIN), Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Timo Roser
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Department of Pediatrics, Dr. von Haunersches Children’s Hospital, Ludwig-Maximilian-University of Munich, 80331 Munich, Germany
| | - Ingo Borggraefe
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Department of Pediatrics, Dr. von Haunersches Children’s Hospital, Ludwig-Maximilian-University of Munich, 80331 Munich, Germany
- Comprehensive Epilepsy Center, Ludwig-Maximilian- University of Munich, 80331 Munich, Germany
| | - Tobias Brünger
- Luxembourg Centre for Systems Biomedicine (LCSB), University Luxembourg, L-4243 Esch-sur-Alzette, Luxembourg
| | - Patrick May
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44102, USA
| | - Dennis Lal
- Luxembourg Centre for Systems Biomedicine (LCSB), University Luxembourg, L-4243 Esch-sur-Alzette, Luxembourg
- Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH 44102, USA
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and M.I.T., Cambridge, MA 02138, USA
- Cologne Center for Genomics (CCG), University of Cologne, 50667 Cologne, Germany
| | - Damien Lederer
- Institute for Pathology and Genetics, 6040 Gosselies, Belgium
| | - Guido Rubboli
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Center, 4293 Dianalund, Denmark
- University of Copenhagen, 2200 Copenhagen, Denmark
| | - Henrike O Heyne
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, 4275 Leipzig, Germany
- Finnish Institute for Molecular Medicine (FIMM), University of Helsinki, 320 Helsinki, Finland
- Program for Medical and Population Genetics/Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02138, USA
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02108, USA
| | - Gaetan Lesca
- Department of Medical Genetics, Groupement Hospitalier Est and ERN EpiCARE, University Hospitals of Lyon (HCL), 69001 Lyon, France
- Institut Neuromyogène, CNRS UMR 5310 - INSERM U1217, Université de Lyon, Université Claude Bernard Lyon 1, 69001 Lyon, France
| | - Ulrike B S Hedrich
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Jan Benda
- Institute for Neurobiology, University of Tuebingen, 72072 Tuebingen, Germany
| | - Elena Gardella
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Center, 4293 Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, 5230 Odense, Denmark
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72072 Tuebingen, Germany
| | - Rikke S Møller
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Center, 4293 Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, 5230 Odense, Denmark
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Osorio-Méndez D, Miller A, Begeman IJ, Kurth A, Hagle R, Rolph D, Dickson AL, Chen CH, Halloran M, Poss KD, Kang J. Voltage-gated sodium channel scn8a is required for innervation and regeneration of amputated adult zebrafish fins. Proc Natl Acad Sci U S A 2022; 119:e2200342119. [PMID: 35867745 PMCID: PMC9282381 DOI: 10.1073/pnas.2200342119] [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: 01/11/2022] [Accepted: 05/10/2022] [Indexed: 01/09/2023] Open
Abstract
Teleost fishes and urodele amphibians can regenerate amputated appendages, whereas this ability is restricted to digit tips in adult mammals. One key component of appendage regeneration is reinnervation of the wound area. However, how innervation is regulated in injured appendages of adult vertebrates has seen limited research attention. From a forward genetics screen for temperature-sensitive defects in zebrafish fin regeneration, we identified a mutation that disrupted regeneration while also inducing paralysis at the restrictive temperature. Genetic mapping and complementation tests identify a mutation in the major neuronal voltage-gated sodium channel (VGSC) gene scn8ab. Conditional disruption of scn8ab impairs early regenerative events, including blastema formation, but does not affect morphogenesis of established regenerates. Whereas scn8ab mutations reduced neural activity as expected, they also disrupted axon regrowth and patterning in fin regenerates, resulting in hypoinnervation. Our findings indicate that the activity of VGSCs plays a proregenerative role by promoting innervation of appendage stumps.
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Affiliation(s)
- Daniel Osorio-Méndez
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705
| | - Andrew Miller
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53705
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705
| | - Ian J. Begeman
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705
| | - Andrew Kurth
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705
| | - Ryan Hagle
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705
| | - Daniela Rolph
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705
| | - Amy L. Dickson
- Duke Regeneration Center, Department of Cell Biology, Duke University Medical Center, Durham, NC 27710
| | - Chen-Hui Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Mary Halloran
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53705
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705
| | - Kenneth D. Poss
- Duke Regeneration Center, Department of Cell Biology, Duke University Medical Center, Durham, NC 27710
| | - Junsu Kang
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705
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25
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Knowles JK, Xu H, Soane C, Batra A, Saucedo T, Frost E, Tam LT, Fraga D, Ni L, Villar K, Talmi S, Huguenard JR, Monje M. Maladaptive myelination promotes generalized epilepsy progression. Nat Neurosci 2022; 25:596-606. [PMID: 35501379 PMCID: PMC9076538 DOI: 10.1038/s41593-022-01052-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 03/14/2022] [Indexed: 12/18/2022]
Abstract
Activity-dependent myelination can fine-tune neural network dynamics. Conversely, aberrant neuronal activity, as occurs in disorders of recurrent seizures (epilepsy), could promote maladaptive myelination, contributing to pathogenesis. In this study, we tested the hypothesis that activity-dependent myelination resulting from absence seizures, which manifest as frequent behavioral arrests with generalized electroencephalography (EEG) spike-wave discharges, promote thalamocortical network hypersynchrony and contribute to epilepsy progression. We found increased oligodendrogenesis and myelination specifically within the seizure network in two models of generalized epilepsy with absence seizures (Wag/Rij rats and Scn8a+/mut mice), evident only after epilepsy onset. Aberrant myelination was prevented by pharmacological seizure inhibition in Wag/Rij rats. Blocking activity-dependent myelination decreased seizure burden over time and reduced ictal synchrony as assessed by EEG coherence. These findings indicate that activity-dependent myelination driven by absence seizures contributes to epilepsy progression; maladaptive myelination may be pathogenic in some forms of epilepsy and other neurological diseases.
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Affiliation(s)
- Juliet K Knowles
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.
| | - Haojun Xu
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.,Ph.D. Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, Tsukuba, Japan
| | - Caroline Soane
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Ankita Batra
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Tristan Saucedo
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Eleanor Frost
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Lydia T Tam
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Danielle Fraga
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Lijun Ni
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Katlin Villar
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Sydney Talmi
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - John R Huguenard
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.
| | - Michelle Monje
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA. .,Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA.
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26
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Mangano GD, Fontana A, Antona V, Salpietro V, Mangano GR, Giuffrè M, Nardello R. Commonalities and distinctions between two neurodevelopmental disorder subtypes associated with SCN2A and SCN8A variants and literature review. Mol Genet Genomic Med 2022; 10:e1911. [PMID: 35348308 PMCID: PMC9034667 DOI: 10.1002/mgg3.1911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/02/2022] [Accepted: 02/07/2022] [Indexed: 01/29/2023] Open
Abstract
This study was aimed to analyze the commonalities and distinctions of voltage‐gated sodium channels, Nav1.2, Nav1.6, in neurodevelopmental disorders. An observational study was performed including two patients with neurodevelopmental disorders. The demographic, electroclinical, genetic, and neuropsychological characteristics were analyzed and compared with each other and then with the subjects carrying the same genetic variants reported in the literature. The clinical features of one of them argued for autism spectrum disorder and developmental delay, the other for intellectual disability, diagnoses confirmed by the neuropsychological assessment. The first patient was a carrier of SCN2A (p.R379H) variant while the second was carrier of SCN8A (p.E936K) variant, both involving the pore loop of the two channels. The results of this study suggest that the neurodevelopmental disorders without overt epilepsy of both patients can be the consequences of loss of function of Nav1.2/Nav1.6 channels. Notably, the SCN2A variant, with an earlier expression timing in brain development, resulted in a more severe phenotype as autism spectrum disorder and developmental delay, while the SCN8A variant, with a later expression timing, resulted in a less severe phenotype as intellectual disability.
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Affiliation(s)
- Giuseppe Donato Mangano
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | - Antonina Fontana
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | - Vincenzo Antona
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | - Vincenzo Salpietro
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK.,Department of Neurosciences Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa; Pediatric Neurology and Muscular Diseases Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Giuseppa Renata Mangano
- Department of Psychology, Educational Sciences and Human Movement, University of Palermo, Palermo, Italy
| | - Mario Giuffrè
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | - Rosaria Nardello
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
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27
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Chang B, Byun J, Kim KK, Lee SE, Lee B, Kim KS, Ryu H, Shin HS, Cheong E. Deletion of Phospholipase C β1 in the Thalamic Reticular Nucleus Induces Absence Seizures. Exp Neurobiol 2022; 31:116-130. [PMID: 35674000 PMCID: PMC9194639 DOI: 10.5607/en22007] [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: 02/24/2022] [Revised: 03/22/2022] [Accepted: 04/05/2022] [Indexed: 11/29/2022] Open
Abstract
Absence seizures are caused by abnormal synchronized oscillations in the thalamocortical (TC) circuit, which result in widespread spike-and-wave discharges (SWDs) on electroencephalography (EEG) as well as impairment of consciousness. Thalamic reticular nucleus (TRN) and TC neurons are known to interact dynamically to generate TC circuitry oscillations during SWDs. Clinical studies have suggested the association of Plcβ1 with early-onset epilepsy, including absence seizures. However, the brain regions and circuit mechanisms related to the generation of absence seizures with Plcβ1 deficiency are unknown. In this study, we found that loss of Plcβ1 in mice caused spontaneous complex-type seizures, including convulsive and absence seizures. Importantly, TRN-specific deletion of Plcβ1 led to the development of only spontaneous SWDs, and no other types of seizures were observed. Ex vivo slice patch recording demonstrated that the number of spikes, an intrinsic TRN neuronal property, was significantly reduced in both tonic and burst firing modes in the absence of Plcβ1. We conclude that the loss of Plcβ1 in the TRN leads to decreased excitability and impairs normal inhibitory neuronal function, thereby disrupting feedforward inhibition of the TC circuitry, which is sufficient to cause hypersynchrony of the TC system and eventually leads to spontaneous absence seizures. Our study not only provides a novel mechanism for the induction of SWDs in Plcβ1-deficient patients but also offers guidance for the development of diagnostic and therapeutic tools for absence epilepsy.
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Affiliation(s)
- Bomi Chang
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea.,Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea.,Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Junweon Byun
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - Ko Keun Kim
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - Seung Eun Lee
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Boyoung Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - Key-Sun Kim
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Hoon Ryu
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Hee-Sup Shin
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Korea
| | - Eunji Cheong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
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28
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Stoler O, Stavsky A, Khrapunsky Y, Melamed I, Stutzmann GE, Gitler D, Sekler I, Fleidervish I. Frequency- and spike-timing-dependent mitochondrial Ca 2+ signaling regulates the metabolic rate and synaptic efficacy in cortical. eLife 2022; 11:74606. [PMID: 35192454 PMCID: PMC8906805 DOI: 10.7554/elife.74606] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 02/20/2022] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial activity is crucial for the plasticity of central synapses, but how the firing pattern of pre- and postsynaptic neurons affects the mitochondria remains elusive. We recorded changes in the fluorescence of cytosolic and mitochondrial Ca2+ indicators in cell bodies, axons, and dendrites of cortical pyramidal neurons in mouse brain slices while evoking pre- and postsynaptic spikes. Postsynaptic spike firing elicited fast mitochondrial Ca2+ responses that were about threefold larger in the somas and apical dendrites than in basal dendrites and axons. The amplitude of these responses and metabolic activity were extremely sensitive to the firing frequency. Furthermore, while an EPSP alone caused no detectable Ca2+ elevation in the dendritic mitochondria, the coincidence of EPSP with a backpropagating spike produced prominent, highly localized mitochondrial Ca2+ hotspots. Our results indicate that mitochondria decode the spike firing frequency and the Hebbian temporal coincidences into the Ca2+ signals, which are further translated into the metabolic output and most probably lead to long-term changes in synaptic efficacy.
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Affiliation(s)
- Ohad Stoler
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Alexandra Stavsky
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Yana Khrapunsky
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Israel Melamed
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Grace E Stutzmann
- Rosalind Franklin University of Medicine and Science, North Chicago, United States
| | - Daniel Gitler
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Israel Sekler
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Ilya Fleidervish
- Depatrment of Physiology and Cell Biology, Ben Gurion University of the Negev, Beer Sheva, Israel
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29
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Xu C, Zhang Y, Gozal D, Carney P. Channelopathy of Dravet Syndrome and Potential Neuroprotective Effects of Cannabidiol. J Cent Nerv Syst Dis 2021; 13:11795735211048045. [PMID: 34992485 PMCID: PMC8724990 DOI: 10.1177/11795735211048045] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Dravet syndrome (DS) is a channelopathy, neurodevelopmental, epileptic encephalopathy characterized by seizures, developmental delay, and cognitive impairment that includes susceptibility to thermally induced seizures, spontaneous seizures, ataxia, circadian rhythm and sleep disorders, autistic-like behaviors, and premature death. More than 80% of DS cases are linked to mutations in genes which encode voltage-gated sodium channel subunits, SCN1A and SCN1B, which encode the Nav1.1α subunit and Nav1.1β1 subunit, respectively. There are other gene mutations encoding potassium, calcium, and hyperpolarization-activated cyclic nucleotide-gated (HCN) channels related to DS. One-third of patients have pharmacoresistance epilepsy. DS is unresponsive to standard therapy. Cannabidiol (CBD), a non-psychoactive phytocannabinoid present in Cannabis, has been introduced for treating DS because of its anticonvulsant properties in animal models and humans, especially in pharmacoresistant patients. However, the etiological channelopathiological mechanism of DS and action mechanism of CBD on the channels are unclear. In this review, we summarize evidence of the direct and indirect action mechanism of sodium, potassium, calcium, and HCN channels in DS, especially sodium subunits. Some channels' loss-of-function or gain-of-function in inhibitory or excitatory neurons determine the balance of excitatory and inhibitory are associated with DS. A great variety of mechanisms of CBD anticonvulsant effects are focused on modulating these channels, especially sodium, calcium, and potassium channels, which will shed light on ionic channelopathy of DS and the precise molecular treatment of DS in the future.
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Affiliation(s)
- Changqing Xu
- Department of Child Health and the Child Health Research Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Yumin Zhang
- Department of Anatomy, Physiology and Genetics; Department of Neuroscience, Uniformed Services University School of Medicine, Bethesda, MD, USA
| | - David Gozal
- Department of Child Health and the Child Health Research Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Paul Carney
- Departments of Child Health and Neurology, School of Medicine, University of Missouri, Columbia, MO, USA
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30
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Liu Y, Koko M, Lerche H. A SCN8A variant associated with severe early onset epilepsy and developmental delay: Loss- or gain-of-function? Epilepsy Res 2021; 178:106824. [PMID: 34847423 DOI: 10.1016/j.eplepsyres.2021.106824] [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: 07/06/2021] [Revised: 11/12/2021] [Accepted: 11/16/2021] [Indexed: 10/19/2022]
Abstract
SCN8A, encoding the voltage-gated sodium channel subunit NaV1.6, has been associated with a wide spectrum of neuropsychiatric disorders. Missense variants in SCN8A which increase the channel activity can cause a severe developmental and epileptic encephalopathy (DEE). One DEE variant (p.(Arg223Gly)) was described to cause a predominant loss-of-function (LOF) mechanism when expressed in neuroblastoma cells, which is not consistent with the genotype-phenotype correlations in this gene. To resolve this discrepancy and understand the pathophysiological mechanism of this variant, we performed comprehensive electrophysiological studies in both neuroblastoma cells and primary hippocampal neuronal cultures. Although we also found that p.(Arg223Gly) significantly decreased Na+ current density and enhanced fast inactivation compared to the wild type (WT) channel in transfected neuroblastoma cells (both LOF mechanisms), it also caused a strong hyperpolarizing shift of steady-state activation and accelerated the recovery from fast inactivation (both gain-of-function (GOF) mechanisms). In cultured neurons transfected with mutant vs. WT NaV1.6 channels, we found more depolarized resting membrane potentials and a decreased rheobase leading to enhanced action potential firing. We conclude that SCN8A p.(Arg223Gly) leads to a net GOF resulting in neuronal hyperexcitability and a higher firing rate, fitting with the central role of GOF mechanisms in DEE.
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Affiliation(s)
- Yuanyuan Liu
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
| | - Mahmoud Koko
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany.
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31
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Somatostatin-Positive Interneurons Contribute to Seizures in SCN8A Epileptic Encephalopathy. J Neurosci 2021; 41:9257-9273. [PMID: 34544834 DOI: 10.1523/jneurosci.0718-21.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SCN8A epileptic encephalopathy is a devastating epilepsy syndrome caused by mutant SCN8A, which encodes the voltage-gated sodium channel NaV1.6. To date, it is unclear if and how inhibitory interneurons, which express NaV1.6, influence disease pathology. Using both sexes of a transgenic mouse model of SCN8A epileptic encephalopathy, we found that selective expression of the R1872W SCN8A mutation in somatostatin (SST) interneurons was sufficient to convey susceptibility to audiogenic seizures. Patch-clamp electrophysiology experiments revealed that SST interneurons from mutant mice were hyperexcitable but hypersensitive to action potential failure via depolarization block under normal and seizure-like conditions. Remarkably, GqDREADD-mediated activation of WT SST interneurons resulted in prolonged electrographic seizures and was accompanied by SST hyperexcitability and depolarization block. Aberrantly large persistent sodium currents, a hallmark of SCN8A mutations, were observed and were found to contribute directly to aberrant SST physiology in computational modeling and pharmacological experiments. These novel findings demonstrate a critical and previously unidentified contribution of SST interneurons to seizure generation not only in SCN8A epileptic encephalopathy, but epilepsy in general.SIGNIFICANCE STATEMENT SCN8A epileptic encephalopathy is a devastating neurological disorder that results from de novo mutations in the sodium channel isoform Nav1.6. Inhibitory neurons express NaV1.6, yet their contribution to seizure generation in SCN8A epileptic encephalopathy has not been determined. We show that mice expressing a human-derived SCN8A variant (R1872W) selectively in somatostatin (SST) interneurons have audiogenic seizures. Physiological recordings from SST interneurons show that SCN8A mutations lead to an elevated persistent sodium current which drives initial hyperexcitability, followed by premature action potential failure because of depolarization block. Furthermore, chemogenetic activation of WT SST interneurons leads to audiogenic seizure activity. These findings provide new insight into the importance of SST inhibitory interneurons in seizure initiation, not only in SCN8A epileptic encephalopathy, but for epilepsy broadly.
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32
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Necula D, Cho FS, He A, Paz JT. Secondary thalamic neuroinflammation after focal cortical stroke and traumatic injury mirrors corticothalamic functional connectivity. J Comp Neurol 2021; 530:998-1019. [PMID: 34633669 PMCID: PMC8957545 DOI: 10.1002/cne.25259] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 10/03/2021] [Accepted: 10/04/2021] [Indexed: 12/29/2022]
Abstract
While cortical injuries, such as traumatic brain injury (TBI) and neocortical stroke, acutely disrupt the neocortex, most of their consequent disabilities reflect secondary injuries that develop over time. Thalamic neuroinflammation has been proposed to be a biomarker of cortical injury and of the long-term cognitive and neurological deficits that follow. However, the extent to which thalamic neuroinflammation depends on the type of cortical injury or its location remains unknown. Using two mouse models of focal neocortical injury that do not directly damage subcortical structures-controlled cortical impact and photothrombotic ischemic stroke-we found that chronic neuroinflammation in the thalamic region mirrors the functional connections with the injured cortex, and that sensory corticothalamic regions may be more likely to sustain long-term damage than nonsensory circuits. Currently, heterogeneous clinical outcomes complicate treatment. Understanding how thalamic inflammation depends on the injury site can aid in predicting features of subsequent deficits and lead to more effective, customized therapies.
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Affiliation(s)
- Deanna Necula
- Gladstone Institute of Neurological Disease, San Francisco, California, USA.,Neuroscience Graduate Program, University of California, San Francisco, California, USA.,Department of Neurology and the Kavli Institute for Fundamental Neuroscience, University of California San Francisco, San Francisco, California, USA
| | - Frances S Cho
- Gladstone Institute of Neurological Disease, San Francisco, California, USA.,Neuroscience Graduate Program, University of California, San Francisco, California, USA.,Department of Neurology and the Kavli Institute for Fundamental Neuroscience, University of California San Francisco, San Francisco, California, USA
| | - Andrea He
- Gladstone Institute of Neurological Disease, San Francisco, California, USA
| | - Jeanne T Paz
- Gladstone Institute of Neurological Disease, San Francisco, California, USA.,Neuroscience Graduate Program, University of California, San Francisco, California, USA.,Department of Neurology and the Kavli Institute for Fundamental Neuroscience, University of California San Francisco, San Francisco, California, USA
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33
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Autistic-like behavior, spontaneous seizures, and increased neuronal excitability in a Scn8a mouse model. Neuropsychopharmacology 2021; 46:2011-2020. [PMID: 33658654 PMCID: PMC8429750 DOI: 10.1038/s41386-021-00985-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 02/05/2023]
Abstract
Patients with SCN8A epileptic encephalopathy exhibit a range of clinical features, including multiple seizure types, movement disorders, and behavioral abnormalities, such as developmental delay, mild-to-severe intellectual disability, and autism. Recently, the de novo heterozygous SCN8A R1620L mutation was identified in an individual with autism, intellectual disability, and behavioral seizures without accompanying electrographic seizure activity. To date, the effects of SCN8A mutations that are primarily associated with behavioral abnormalities have not been studied in a mouse model. To better understand the phenotypic and functional consequences of the R1620L mutation, we used CRISPR/Cas9 technology to generate mice expressing the corresponding SCN8A amino acid substitution. Homozygous mutants exhibit tremors and a maximum lifespan of 22 days, while heterozygous mutants (RL/+) exhibit autistic-like behaviors, such as hyperactivity and learning and social deficits, increased seizure susceptibility, and spontaneous seizures. Current clamp analyses revealed a reduced threshold for firing action potentials in heterozygous CA3 pyramidal neurons and reduced firing frequency, suggesting that the R1620L mutation has both gain- and loss-of-function effects. In vivo calcium imaging using miniscopes in freely moving RL/+ mutants showed hyperexcitability of cortical excitatory neurons that is likely to increase seizure susceptibility. Finally, we found that oxcarbazepine and Huperzine A, a sodium channel blocker and reversible acetylcholinesterase inhibitor, respectively, were capable of conferring robust protection against induced seizures in RL/+ mutants. This mouse line will provide the opportunity to better understand the range of clinical phenotypes associated with SCN8A mutations and to develop new therapeutic approaches.
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34
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Spratt PWE, Alexander RPD, Ben-Shalom R, Sahagun A, Kyoung H, Keeshen CM, Sanders SJ, Bender KJ. Paradoxical hyperexcitability from Na V1.2 sodium channel loss in neocortical pyramidal cells. Cell Rep 2021; 36:109483. [PMID: 34348157 PMCID: PMC8719649 DOI: 10.1016/j.celrep.2021.109483] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/17/2021] [Accepted: 07/13/2021] [Indexed: 12/17/2022] Open
Abstract
Loss-of-function variants in the gene SCN2A, which encodes the sodium channel NaV1.2, are strongly associated with autism spectrum disorder and intellectual disability. An estimated 20%-30% of children with these variants also suffer from epilepsy, with altered neuronal activity originating in neocortex, a region where NaV1.2 channels are expressed predominantly in excitatory pyramidal cells. This is paradoxical, as sodium channel loss in excitatory cells would be expected to dampen neocortical activity rather than promote seizure. Here, we examined pyramidal neurons lacking NaV1.2 channels and found that they were intrinsically hyperexcitable, firing high-frequency bursts of action potentials (APs) despite decrements in AP size and speed. Compartmental modeling and dynamic-clamp recordings revealed that NaV1.2 loss prevented potassium channels from properly repolarizing neurons between APs, increasing overall excitability by allowing neurons to reach threshold for subsequent APs more rapidly. This cell-intrinsic mechanism may, therefore, account for why SCN2A loss-of-function can paradoxically promote seizure.
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Affiliation(s)
- Perry W E Spratt
- Neuroscience Graduate Program, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Ryan P D Alexander
- Department of Neurology, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Roy Ben-Shalom
- Department of Neurology, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Atehsa Sahagun
- Department of Neurology, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Henry Kyoung
- Department of Neurology, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Caroline M Keeshen
- Department of Neurology, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Stephan J Sanders
- Department of Psychiatry, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Kevin J Bender
- Neuroscience Graduate Program, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Department of Neurology, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA.
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35
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Zhang J, Chen X, Eaton M, Wu J, Ma Z, Lai S, Park A, Ahmad TS, Que Z, Lee JH, Xiao T, Li Y, Wang Y, Olivero-Acosta MI, Schaber JA, Jayant K, Yuan C, Huang Z, Lanman NA, Skarnes WC, Yang Y. Severe deficiency of the voltage-gated sodium channel Na V1.2 elevates neuronal excitability in adult mice. Cell Rep 2021; 36:109495. [PMID: 34348148 PMCID: PMC8382316 DOI: 10.1016/j.celrep.2021.109495] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/30/2021] [Accepted: 07/14/2021] [Indexed: 12/13/2022] Open
Abstract
Scn2a encodes the voltage-gated sodium channel NaV1.2, a main mediator of neuronal action potential firing. The current paradigm suggests that NaV1.2 gain-of-function variants enhance neuronal excitability, resulting in epilepsy, whereas NaV1.2 deficiency impairs neuronal excitability, contributing to autism. However, this paradigm does not explain why ∼20%-30% of individuals with NaV1.2 deficiency still develop seizures. Here, we report the counterintuitive finding that severe NaV1.2 deficiency results in increased neuronal excitability. Using a NaV1.2-deficient mouse model, we show enhanced intrinsic excitability of principal neurons in the prefrontal cortex and striatum, brain regions known to be involved in Scn2a-related seizures. This increased excitability is autonomous and reversible by genetic restoration of Scn2a expression in adult mice. RNA sequencing reveals downregulation of multiple potassium channels, including KV1.1. Correspondingly, KV channel openers alleviate the hyperexcitability of NaV1.2-deficient neurons. This unexpected neuronal hyperexcitability may serve as a cellular basis underlying NaV1.2 deficiency-related seizures.
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Affiliation(s)
- Jingliang Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Xiaoling Chen
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Muriel Eaton
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Jiaxiang Wu
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Zhixiong Ma
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Shirong Lai
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Anthony Park
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Talha S Ahmad
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Zhefu Que
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Ji Hea Lee
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Tiange Xiao
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Yuansong Li
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Yujia Wang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - Maria I Olivero-Acosta
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
| | - James A Schaber
- Bioscience Imaging Facility, Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907, USA
| | - Krishna Jayant
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Chongli Yuan
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Zhuo Huang
- Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Nadia A Lanman
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN 47907, USA; Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA
| | - William C Skarnes
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Yang Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA.
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36
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Welch WP, Hect JL, Abel TJ. Case Report: Responsive Neurostimulation of the Centromedian Thalamic Nucleus for the Detection and Treatment of Seizures in Pediatric Primary Generalized Epilepsy. Front Neurol 2021; 12:656585. [PMID: 33995254 PMCID: PMC8113700 DOI: 10.3389/fneur.2021.656585] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
Up to 20% of pediatric patients with primary generalized epilepsy (PGE) will not respond effectively to medication for seizure control. Responsive neurostimulation (RNS) is a promising therapy for pediatric patients with drug-resistant epilepsy and has been shown to be an effective therapy for reducing seizure frequency and severity in adult patients. RNS of the centromedian nucleus of the thalamus may help to prevent loss of awareness during seizure activity in PGE patients with absence seizures. Here we present a 16-year-old male, with drug-resistant PGE with absence seizures, characterized by 3 Hz spike-and-slow-wave discharges on EEG, who achieved a 75% reduction in seizure frequency following bilateral RNS of the centromedian nuclei. At 6-months post-implant, this patient reported complete resolution of the baseline daily absence seizure activity, and decrease from 3-4 generalized convulsive seizures per month to 1 per month. RNS recordings showed well-formed 3 Hz spike-wave discharges in bilateral CM nuclei, further supporting the notion that clinically relevant ictal discharges in PGE can be detected in CM. This report demonstrates that CM RNS can detect PGE-related seizures in the CM nucleus and deliver therapeutic stimulation.
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Affiliation(s)
- William P Welch
- Division of Pediatric Neurology, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jasmine L Hect
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Taylor J Abel
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA, United States
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37
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Mantegazza M, Cestèle S, Catterall WA. Sodium channelopathies of skeletal muscle and brain. Physiol Rev 2021; 101:1633-1689. [PMID: 33769100 DOI: 10.1152/physrev.00025.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Voltage-gated sodium channels initiate action potentials in nerve, skeletal muscle, and other electrically excitable cells. Mutations in them cause a wide range of diseases. These channelopathy mutations affect every aspect of sodium channel function, including voltage sensing, voltage-dependent activation, ion conductance, fast and slow inactivation, and both biosynthesis and assembly. Mutations that cause different forms of periodic paralysis in skeletal muscle were discovered first and have provided a template for understanding structure, function, and pathophysiology at the molecular level. More recent work has revealed multiple sodium channelopathies in the brain. Here we review the well-characterized genetics and pathophysiology of the periodic paralyses of skeletal muscle and then use this information as a foundation for advancing our understanding of mutations in the structurally homologous α-subunits of brain sodium channels that cause epilepsy, migraine, autism, and related comorbidities. We include studies based on molecular and structural biology, cell biology and physiology, pharmacology, and mouse genetics. Our review reveals unexpected connections among these different types of sodium channelopathies.
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Affiliation(s)
- Massimo Mantegazza
- Université Cote d'Azur, Valbonne-Sophia Antipolis, France.,CNRS UMR7275, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne-Sophia Antipolis, France.,INSERM, Valbonne-Sophia Antipolis, France
| | - Sandrine Cestèle
- Université Cote d'Azur, Valbonne-Sophia Antipolis, France.,CNRS UMR7275, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne-Sophia Antipolis, France
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38
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O'Reilly C, Iavarone E, Yi J, Hill SL. Rodent somatosensory thalamocortical circuitry: Neurons, synapses, and connectivity. Neurosci Biobehav Rev 2021; 126:213-235. [PMID: 33766672 DOI: 10.1016/j.neubiorev.2021.03.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 02/15/2021] [Accepted: 03/14/2021] [Indexed: 01/21/2023]
Abstract
As our understanding of the thalamocortical system deepens, the questions we face become more complex. Their investigation requires the adoption of novel experimental approaches complemented with increasingly sophisticated computational modeling. In this review, we take stock of current data and knowledge about the circuitry of the somatosensory thalamocortical loop in rodents, discussing common principles across modalities and species whenever appropriate. We review the different levels of organization, including the cells, synapses, neuroanatomy, and network connectivity. We provide a complete overview of this system that should be accessible for newcomers to this field while nevertheless being comprehensive enough to serve as a reference for seasoned neuroscientists and computational modelers studying the thalamocortical system. We further highlight key gaps in data and knowledge that constitute pressing targets for future experimental work. Filling these gaps would provide invaluable information for systematically unveiling how this system supports behavioral and cognitive processes.
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Affiliation(s)
- Christian O'Reilly
- Azrieli Centre for Autism Research, Montreal Neurological Institute, McGill University, Montreal, Canada; Ronin Institute, Montclair, NJ, USA; Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland.
| | - Elisabetta Iavarone
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Jane Yi
- Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Sean L Hill
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland; Department of Psychiatry, University of Toronto, Toronto, Canada; Centre for Addiction and Mental Health, Toronto, Canada.
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39
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Abstract
The voltage-gated sodium channel α-subunit genes comprise a highly conserved gene family. Mutations of three of these genes, SCN1A, SCN2A and SCN8A, are responsible for a significant burden of neurological disease. Recent progress in identification and functional characterization of patient variants is generating new insights and novel approaches to therapy for these devastating disorders. Here we review the basic elements of sodium channel function that are used to characterize patient variants. We summarize a large body of work using global and conditional mouse mutants to characterize the in vivo roles of these channels. We provide an overview of the neurological disorders associated with mutations of the human genes and examples of the effects of patient mutations on channel function. Finally, we highlight therapeutic interventions that are emerging from new insights into mechanisms of sodium channelopathies.
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40
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Raiders S, Han T, Scott-Hewitt N, Kucenas S, Lew D, Logan MA, Singhvi A. Engulfed by Glia: Glial Pruning in Development, Function, and Injury across Species. J Neurosci 2021; 41:823-833. [PMID: 33468571 PMCID: PMC7880271 DOI: 10.1523/jneurosci.1660-20.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/20/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023] Open
Abstract
Phagocytic activity of glial cells is essential for proper nervous system sculpting, maintenance of circuitry, and long-term brain health. Glial engulfment of apoptotic cells and superfluous connections ensures that neuronal connections are appropriately refined, while clearance of damaged projections and neurotoxic proteins in the mature brain protects against inflammatory insults. Comparative work across species and cell types in recent years highlights the striking conservation of pathways that govern glial engulfment. Many signaling cascades used during developmental pruning are re-employed in the mature brain to "fine tune" synaptic architecture and even clear neuronal debris following traumatic events. Moreover, the neuron-glia signaling events required to trigger and perform phagocytic responses are impressively conserved between invertebrates and vertebrates. This review offers a compare-and-contrast portrayal of recent findings that underscore the value of investigating glial engulfment mechanisms in a wide range of species and contexts.
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Affiliation(s)
- Stephan Raiders
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, Washington 98195
| | - Taeho Han
- UCSF Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California 94158
| | - Nicole Scott-Hewitt
- F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Boston, Massachusetts 02115
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142
| | - Sarah Kucenas
- Department of Biology, University of Virginia, Charlottesville, Virginia 22904
| | - Deborah Lew
- Department of Biological Sciences, Fordham University, Bronx, New York 10458
| | - Mary A Logan
- Jungers Center, Department of Neurology, Oregon Health and Science University, Portland, Oregon 97239
| | - Aakanksha Singhvi
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, Washington 98195
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41
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Wang W, Frankel WN. Overlaps, gaps, and complexities of mouse models of Developmental and Epileptic Encephalopathy. Neurobiol Dis 2021; 148:105220. [PMID: 33301879 PMCID: PMC8547712 DOI: 10.1016/j.nbd.2020.105220] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/17/2020] [Accepted: 12/04/2020] [Indexed: 11/28/2022] Open
Abstract
Mouse models have made innumerable contributions to understanding the genetic basis of neurological disease and pathogenic mechanisms and to therapy development. Here we consider the current state of mouse genetic models of Developmental and Epileptic Encephalopathy (DEE), representing a set of rare but devastating and largely intractable childhood epilepsies. By examining the range of mouse lines available in this rapidly moving field and by detailing both expected and unusual features in representative examples, we highlight lessons learned in an effort to maximize the full potential of this powerful resource for preclinical studies.
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Affiliation(s)
- Wanqi Wang
- Department of Genetics & Development, Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States of America.
| | - Wayne N Frankel
- Department of Genetics & Development, Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, United States of America.
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42
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Generation of human striatal organoids and cortico-striatal assembloids from human pluripotent stem cells. Nat Biotechnol 2020; 38:1421-1430. [PMID: 33273741 PMCID: PMC9042317 DOI: 10.1038/s41587-020-00763-w] [Citation(s) in RCA: 179] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 11/02/2020] [Indexed: 12/11/2022]
Abstract
Cortico-striatal projections are critical components of forebrain circuitry that regulate motivated behaviors. To enable the study of the human cortico-striatal pathway and how its dysfunction leads to neuropsychiatric disease, we developed a method to convert human pluripotent stem cells into region-specific brain organoids that resemble the developing human striatum and include electrically active medium spiny neurons. We then assembled these organoids with cerebral cortical organoids in three-dimensional cultures to form cortico-striatal assembloids. Using viral tracing and functional assays in intact or sliced assembloids, we show that cortical neurons send axonal projections into striatal organoids and form synaptic connections. Medium spiny neurons mature electrophysiologically following assembly and display calcium activity after optogenetic stimulation of cortical neurons. Moreover, we derive cortico-striatal assembloids from patients with a neurodevelopmental disorder caused by a deletion on chromosome 22q13.3 and capture disease-associated defects in calcium activity, showing that this approach will allow investigation of the development and functional assembly of cortico-striatal connectivity using patient-derived cells.
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43
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Huguenard JR. Perspective: Is Cortical Hyperexcitability the Only Path to Generalized Absence Epilepsy? Epilepsy Curr 2020; 20:59S-61S. [PMID: 33287573 PMCID: PMC7726732 DOI: 10.1177/1535759720959325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- John R Huguenard
- Department of Neurology and Neurological Sciences, 10624Stanford University, Neurosciences Building, 290 Jane Stanford Way, Stanford, CA 94305, USA
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44
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Menezes LFS, Sabiá Júnior EF, Tibery DV, Carneiro LDA, Schwartz EF. Epilepsy-Related Voltage-Gated Sodium Channelopathies: A Review. Front Pharmacol 2020; 11:1276. [PMID: 33013363 PMCID: PMC7461817 DOI: 10.3389/fphar.2020.01276] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/31/2020] [Indexed: 12/29/2022] Open
Abstract
Epilepsy is a disease characterized by abnormal brain activity and a predisposition to generate epileptic seizures, leading to neurobiological, cognitive, psychological, social, and economic impacts for the patient. There are several known causes for epilepsy; one of them is the malfunction of ion channels, resulting from mutations. Voltage-gated sodium channels (NaV) play an essential role in the generation and propagation of action potential, and malfunction caused by mutations can induce irregular neuronal activity. That said, several genetic variations in NaV channels have been described and associated with epilepsy. These mutations can affect channel kinetics, modifying channel activation, inactivation, recovery from inactivation, and/or the current window. Among the NaV subtypes related to epilepsy, NaV1.1 is doubtless the most relevant, with more than 1500 mutations described. Truncation and missense mutations are the most observed alterations. In addition, several studies have already related mutated NaV channels with the electrophysiological functioning of the channel, aiming to correlate with the epilepsy phenotype. The present review provides an overview of studies on epilepsy-associated mutated human NaV1.1, NaV1.2, NaV1.3, NaV1.6, and NaV1.7.
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Affiliation(s)
- Luis Felipe Santos Menezes
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Elias Ferreira Sabiá Júnior
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Diogo Vieira Tibery
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Lilian Dos Anjos Carneiro
- Faculdade de Medicina, Centro Universitário Euro Americano, Brasília, Brazil.,Faculdade de Medicina, Centro Universitário do Planalto Central, Brasília, Brazil
| | - Elisabeth Ferroni Schwartz
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
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45
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D'Adamo MC, Liantonio A, Conte E, Pessia M, Imbrici P. Ion Channels Involvement in Neurodevelopmental Disorders. Neuroscience 2020; 440:337-359. [PMID: 32473276 DOI: 10.1016/j.neuroscience.2020.05.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/16/2020] [Accepted: 05/19/2020] [Indexed: 12/14/2022]
Abstract
Inherited and sporadic mutations in genes encoding for brain ion channels, affecting membrane expression or biophysical properties, have been associated with neurodevelopmental disorders characterized by epilepsy, cognitive and behavioral deficits with significant phenotypic and genetic heterogeneity. Over the years, the screening of a growing number of patients and the functional characterization of newly identified mutations in ion channels genes allowed to recognize new phenotypes and to widen the clinical spectrum of known diseases. Furthermore, advancements in understanding disease pathogenesis at atomic level or using patient-derived iPSCs and animal models have been pivotal to orient therapeutic intervention and to put the basis for the development of novel pharmacological options for drug-resistant disorders. In this review we will discuss major improvements and critical issues concerning neurodevelopmental disorders caused by dysfunctions in brain sodium, potassium, calcium, chloride and ligand-gated ion channels.
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Affiliation(s)
- Maria Cristina D'Adamo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Malta
| | | | - Elena Conte
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", Italy
| | - Mauro Pessia
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Malta; Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Paola Imbrici
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", Italy.
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46
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Xiao G, Song Y, Zhang Y, Xing Y, Xu S, Lu Z, Wang M, Cai X. Cellular-Scale Microelectrode Arrays to Monitor Movement-Related Neuron Activities in the Epileptic Hippocampus of Awake Mice. IEEE Trans Biomed Eng 2020; 68:19-25. [PMID: 32356734 DOI: 10.1109/tbme.2020.2990356] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Epilepsy affects 50 million people worldwide and its pathogenesis is still unknown. In particular, the movement-related neural activities involving glutamate (Glu) and electrophysiological signals at cellular level remains unclear. METHODS A cellular-scale implantable microelectrode array (MEA) was fabricated to detect the movement-related neural activities involving Glu concentration and electrophysiological signals. Platinum and reduced graphene oxide nanocomposites were deposited to enhance the surface area. Glu oxidase (Gluox) were coated to effectively recognize Glu molecule. RESULTS Neural activities in the hippocampus of normal and epileptic mice is different, and the changes are closely connected with movement. Glu concentration and spike firing rate in the epileptic mice were much higher than those in the normal ones. And the neural activities with significant synchronization were detected in the epileptic mice even without seizure occurrence. Meanwhile, the spikes fire more intensively and Glu level became much higher during the movement of the mice compared to the stationary state. CONCLUSION The existing abnormality of neural activities in the epileptic mice are potential factors to induce a seizure. Movement may impact the neural activities and the duration of seizure. SIGNIFICANCE The MEA can monitor changes of movement, Glu and neuron discharges synchronously and provides us an effective technology to understand the neuronal disease.
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47
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Ritter-Makinson S, Clemente-Perez A, Higashikubo B, Cho FS, Holden SS, Bennett E, Chkhaidze A, Eelkman Rooda OHJ, Cornet MC, Hoebeek FE, Yamakawa K, Cilio MR, Delord B, Paz JT. Augmented Reticular Thalamic Bursting and Seizures in Scn1a-Dravet Syndrome. Cell Rep 2020; 26:54-64.e6. [PMID: 30605686 PMCID: PMC6555418 DOI: 10.1016/j.celrep.2018.12.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/07/2018] [Accepted: 12/03/2018] [Indexed: 11/26/2022] Open
Abstract
Loss of function in the Scn1a gene leads to a severe epileptic encephalopathy called Dravet syndrome (DS). Reduced excitability in cortical inhibitory neurons is thought to be the major cause of DS seizures. Here, in contrast, we show enhanced excitability in thalamic inhibitory neurons that promotes the non-convulsive seizures that are a prominent yet poorly understood feature of DS. In a mouse model of DS with a loss of function in Scn1a, reticular thalamic cells exhibited abnormally long bursts of firing caused by the downregulation of calcium-activated potassium SK channels. Our study supports a mechanism in which loss of SK activity causes the reticular thalamic neurons to become hyperexcitable and promote non-convulsive seizures in DS. We propose that reduced excitability of inhibitory neurons is not global in DS and that non-GABAergic mechanisms such as SK channels may be important targets for treatment. In a mouse model of Dravet syndrome (DS) resulting from voltage-gated sodium channel deficiency, Ritter-Makinson et al. find that inhibitory neurons of the reticular thalamic nucleus are paradoxically hyperexcitable due to compensatory reductions in a potassium SK current. Boosting this SK current treats nonconvulsive seizures in DS mice.
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Affiliation(s)
- Stefanie Ritter-Makinson
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Alexandra Clemente-Perez
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA; Neurosciences Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Bryan Higashikubo
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Frances S Cho
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA; Neurosciences Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Stephanie S Holden
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA; Neurosciences Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Eric Bennett
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Ana Chkhaidze
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Oscar H J Eelkman Rooda
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands; Department of Neurosurgery, Erasmus MC, Rotterdam, the Netherlands
| | - Marie-Coralie Cornet
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Pediatrics, Catholic University of Louvain, Louvain, Belgium
| | - Freek E Hoebeek
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands; Department of Neurosurgery, Erasmus MC, Rotterdam, the Netherlands; NIDOD Institute, Wilhelmina Children's Hospital, University Medical Center Utrecht and Brain Center Rudolf Magnus, Utrecht, the Netherlands
| | - Kazuhiro Yamakawa
- Laboratory for Neurogenetics, RIKEN Brain Science Institute, Wako, Japan
| | - Maria Roberta Cilio
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Bruno Delord
- Institut des Systèmes Intelligents et de Robotique (ISIR), Sorbonne University, 4 Place Jussieu, 75005 Paris, France
| | - Jeanne T Paz
- Gladstone Institute of Neurological Disease, San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA; Neurosciences Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA.
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Spike-and-Wave Discharges Are Not Pathological Sleep Spindles, Network-Level Aspects of Age-Dependent Absence Seizure Development in Rats. eNeuro 2020; 7:ENEURO.0253-19.2019. [PMID: 31862790 PMCID: PMC6944477 DOI: 10.1523/eneuro.0253-19.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 11/04/2019] [Accepted: 12/11/2019] [Indexed: 12/28/2022] Open
Abstract
Spike-and-wave discharges (SWDs) of absence epilepsy are considered as pathologic alterations of sleep spindles; however, their network-level relationship has never been convincingly revealed. In order to observe the development and generalization of the thalamocortical SWDs and the concomitant alterations of sleep related oscillations, we performed local field potential (LFP) and single unit recordings in rats for three months during their maturation. We found that while SWDs and spindles look similar in young, they become different with maturation and shift to appear in different brain states. Thus, despite being generated by the same network, they are likely two distinct manifestations of the thalamocortical activity. We show that while spindles are already mainly global oscillations, SWDs appear mainly only focally in young. They become capable to generalize later with maturation, when the out-of-focus brain regions develop a decreased inhibitory/excitatory balance. These results suggest that a hyperexcitable focus is not sufficient alone to drive generalized absence seizures. Importantly, we also found the gradual age dependent disappearance of sleep spindles coinciding with the simultaneous gradual emergence of spike and waves, which both could be reversed by the proper dosing of ethosuximide (ETX). Based on these observations we conclude that the absence seizure development might be a multi-step process, which might involve the functional impairment of cortical interneurons and network-level changes that negatively affect sleep quality.
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Pan Y, Cummins TR. Distinct functional alterations in SCN8A epilepsy mutant channels. J Physiol 2020; 598:381-401. [PMID: 31715021 PMCID: PMC7216308 DOI: 10.1113/jp278952] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 11/12/2019] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS Mutations in the SCN8A gene cause early infantile epileptic encephalopathy. We characterize a new epilepsy-related SCN8A mutation, R850Q, in the human SCN8A channel and present gain-of-function properties of the mutant channel. Systematic comparison of R850Q with three other SCN8A epilepsy mutations, T761I, R1617Q and R1872Q, identifies one common dysfunction in resurgent current, although these mutations alter distinct properties of the channel. Computational simulations in two different neuron models predict an increased excitability of neurons carrying these mutations, which explains the over-excitation that underlies seizure activities in patients. These data provide further insight into the mechanism of SCN8A-related epilepsy and reveal subtle but potentially important distinction of functional characterization performed in the human vs. rodent channels. ABSTRACT SCN8A is a novel causal gene for early infantile epileptic encephalopathy. It is well accepted that gain-of-function mutations in SCN8A underlie the disorder, although the remarkable heterogeneity of its clinical presentation and poor treatment response demand a better understanding of the disease mechanisms. Here, we characterize a new epilepsy-related SCN8A mutation, R850Q, in human Nav1.6. We show that it is a gain-of-function mutation, with a hyperpolarizing shift in voltage dependence of activation, a two-fold increase of persistent current and a slowed decay of resurgent current. We systematically compare its biophysics with three other SCN8A epilepsy mutations, T767I, R1617Q and R1872Q, in the human Nav1.6 channel. Although all of these mutations are gain-of-function, the mutations affect different aspects of channel properties. One commonality that we discovered is an alteration of resurgent current kinetics, although the mechanisms by which resurgent currents are augmented remain unclear for all of the mutations. Computational simulations predict an increased excitability of neurons carrying these mutations with differential enhancement by open channel blockade.
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Affiliation(s)
- Yanling Pan
- Program in Medical Neuroscience, Paul and Carole Stark Neurosciences Research Institute, Indiana University School of Medicine, IN, USA
| | - Theodore R Cummins
- Paul and Carole Stark Neurosciences Research Institute, Indiana University School of Medicine, IN, USA
- Department of Biology, School of Science, IUPUI, IN, USA
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50
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Schreiber JM, Tochen L, Brown M, Evans S, Ball LJ, Bumbut A, Thewamit R, Whitehead MT, Black C, Boutzoukas E, Fanto E, Suslovic W, Berl M, Hammer M, Gaillard WD. A multi-disciplinary clinic for SCN8A-related epilepsy. Epilepsy Res 2019; 159:106261. [PMID: 31887642 DOI: 10.1016/j.eplepsyres.2019.106261] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/02/2019] [Accepted: 12/21/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVE We endeavored to evaluate a cohort of patients diagnosed with SCN8A-related epilepsy in a multi-disciplinary clinic and to create a bio-repository. METHODS We recruited patients with epilepsy due to SCN8A variants at Children's National Medical Center, through family organizations, or SCN8A.net. Study procedures included medical record review, review of EEG and MRI data, clinical evaluation, the Vineland Adaptive Behavior Scales, Third Edition (VABS-3), DNA extraction, and preparation of peripheral blood mononuclear cells. RESULTS Seventeen patients (9 months - 19 years) completed the study. Age at seizure onset was 1 day to 4 years old (median age 4 months). Epilepsy phenotype ranged from mild epilepsy to severe developmental and epileptic encephalopathy. Medications targeting the voltage-gated sodium channel were most often effective, while levetiracetam resulted in worsening seizures and/or developmental regression in 7/16 (p < 0.05). VABS-3 scores were below age expectations for most children; older children had lower scores. Neurological examination revealed hypotonia (13), spastic quadriparesis (1), ataxia (9), dyskinesia (2)/ dystonia (7), and four non-ambulatory. CONCLUSIONS This is the first report of a large series of patients with epilepsy due to SCN8A variants evaluated in a single multi-disciplinary clinic. By utilizing a more comprehensive and consistent evaluation, we clarify specific seizure and epilepsy types, describe a distinct epilepsy phenotype in a patient with a nonsense variant, delineate patterns of developmental delay, language, and swallow function (specifically anomic aphasia and flaccid dysarthria), identify and characterize movement disorders, report common findings on physical exam, and demonstrate clinical worsening with levetiracetam.
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Affiliation(s)
- John M Schreiber
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Laura Tochen
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Mackenzie Brown
- Children's National Medical Center, Department of Physical Medicine and Rehabilitation, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Sarah Evans
- Children's National Medical Center, Department of Physical Medicine and Rehabilitation, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Laura J Ball
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA; The George Washington University Hospital, 900 23rd St NW, Washington, DC, 20037, USA.
| | - Adrian Bumbut
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Rapeepat Thewamit
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA; Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
| | - Matthew T Whitehead
- Children's National Medical Center, Department of Neuroradiology, 111 Michigan Ave NW, Washington, DC, 20010, USA; Neuroradiology, The George Washington University Hospital, 900 23rd St NW, Washington, DC, 20037, USA.
| | - Chelsea Black
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Emanuel Boutzoukas
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Eleanor Fanto
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - William Suslovic
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Madison Berl
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Michael Hammer
- University of Arizona, Keating Building 111, Department of Anthropology, PO Box 210030, Tucson, AZ, 85721, USA.
| | - William D Gaillard
- Children's National Medical Center, Department of Neurology, 111 Michigan Ave NW, Washington, DC, 20010, USA.
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