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Alves M, Gil B, Villegas-Salmerón J, Salari V, Martins-Ferreira R, Arribas Blázquez M, Menéndez Méndez A, Da Rosa Gerbatin R, Smith J, de Diego-Garcia L, Conte G, Sierra-Marquez J, Merino Serrais P, Mitra M, Fernandez Martin A, Wang Y, Kesavan J, Melia C, Parras A, Beamer E, Zimmer B, Heiland M, Cavanagh B, Parcianello Cipolat R, Morgan J, Teng X, Prehn JHM, Fabene PF, Bertini G, Artalejo AR, Ballestar E, Nicke A, Olivos-Oré LA, Connolly NMC, Henshall DC, Engel T. Opposing effects of the purinergic P2X7 receptor on seizures in neurons and microglia in male mice. Brain Behav Immun 2024; 120:121-140. [PMID: 38777288 DOI: 10.1016/j.bbi.2024.05.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 04/28/2024] [Accepted: 05/19/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND The purinergic ATP-gated P2X7 receptor (P2X7R) is increasingly recognized to contribute to pathological neuroinflammation and brain hyperexcitability. P2X7R expression has been shown to be increased in the brain, including both microglia and neurons, in experimental models of epilepsy and patients. To date, the cell type-specific downstream effects of P2X7Rs during seizures remain, however, incompletely understood. METHODS Effects of P2X7R signaling on seizures and epilepsy were analyzed in induced seizure models using male mice including the kainic acid model of status epilepticus and pentylenetetrazole model and in male and female mice in a genetic model of Dravet syndrome. RNA sequencing was used to analyze P2X7R downstream signaling during seizures. To investigate the cell type-specific role of the P2X7R during seizures and epilepsy, we generated mice lacking exon 2 of the P2rx7 gene in either microglia (P2rx7:Cx3cr1-Cre) or neurons (P2rx7:Thy-1-Cre). To investigate the protective potential of overexpressing P2X7R in GABAergic interneurons, P2X7Rs were overexpressed using adeno-associated virus transduction under the mDlx promoter. RESULTS RNA sequencing of hippocampal tissue from wild-type and P2X7R knock-out mice identified both glial and neuronal genes, in particular genes involved in GABAergic signaling, under the control of the P2X7R following seizures. Mice with deleted P2rx7 in microglia displayed less severe acute seizures and developed a milder form of epilepsy, and microglia displayed an anti-inflammatory molecular profile. In contrast, mice lacking P2rx7 in neurons showed a more severe seizure phenotype when compared to epileptic wild-type mice. Analysis of single-cell expression data revealed that human P2RX7 expression is elevated in the hippocampus of patients with temporal lobe epilepsy in excitatory and inhibitory neurons. Functional studies determined that GABAergic interneurons display increased responses to P2X7R activation in experimental epilepsy. Finally, we show that viral transduction of P2X7R in GABAergic interneurons protects against evoked and spontaneous seizures in experimental temporal lobe epilepsy and in mice lacking Scn1a, a model of Dravet syndrome. CONCLUSIONS Our results suggest a dual and opposing action of P2X7R in epilepsy and suggest P2X7R overexpression in GABAergic interneurons as a novel therapeutic strategy for acquired and, possibly, genetic forms of epilepsy.
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Affiliation(s)
- Mariana Alves
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Beatriz Gil
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Javier Villegas-Salmerón
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; The SFI Centre for Research Training in Genomics Data Science, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Valentina Salari
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Medicine, University of Verona, 37134 Verona, Italy
| | - Ricardo Martins-Ferreira
- Epigenetics and Immune Disease Group, Josep Carreras Research Institute (IJC), 08916 Badalona, Barcelona, Spain; Immunogenetics Laboratory, Molecular Pathology and Immunology, Instituto de Ciências Biomédicas Abel Salazar - Universidade do Porto (ICBAS-UP), Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; Autoimmunity and Neuroscience Group, UMIB - Unit for Multidisciplinary Research in Biomedicine, ICBAS - School of Medicine and Biomedical Sciences, University of Porto, Porto, Portugal; ITR - Laboratory for Integrative and Translational Research in Population Health, Porto, Portugal
| | - Marina Arribas Blázquez
- Department of Pharmacology and Toxicology, Veterinary Faculty, Universidad Complutense de Madrid, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - Aida Menéndez Méndez
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; Department of Medicine, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670, Villaviciosa de Odon, Spain
| | - Rogerio Da Rosa Gerbatin
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Jonathon Smith
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Laura de Diego-Garcia
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; Ocupharm Research Group, Faculty of Optics and Optometry, Complutense University of Madrid, Avda. Arcos de Jalon, 118 (28037), Madrid, Spain
| | - Giorgia Conte
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Juan Sierra-Marquez
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany; Laboratorio Cajal de Circuitos Corticales (CTB), Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Campus Montegancedo S/N, Pozuelo de Alarcon, 28223 Madrid, Spain; Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid 28002, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, Madrid 28031, Spain
| | - Paula Merino Serrais
- Laboratorio Cajal de Circuitos Corticales (CTB), Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Campus Montegancedo S/N, Pozuelo de Alarcon, 28223 Madrid, Spain
| | - Meghma Mitra
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Ana Fernandez Martin
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Yitao Wang
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Jaideep Kesavan
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Ciara Melia
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; VivoArchitect, Route de la Corniche 5, 1066 Epalinges, Vaud, Switzerland
| | - Alberto Parras
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland
| | - Edward Beamer
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; School of Science and Technology, Nottingham Trent University, Nottingham, UK
| | - Béla Zimmer
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Mona Heiland
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Brenton Cavanagh
- Cellular and Molecular Imaging Core, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
| | - Rafael Parcianello Cipolat
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - James Morgan
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, M13 9PL, UK
| | - Xinchen Teng
- College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Jochen H M Prehn
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Paolo F Fabene
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Medicine, University of Verona, 37134 Verona, Italy; Section of Anatomy and Histology, Department of Neurosciences, Biomedicine, and Movement Science, Faculty of Medicine, University of Verona, Verona, Italy; Section of Innovation Biomedicine, Department of Engineering for Innovation Medicine, Faculty of Medicine, University of Verona, Verona, Italy
| | - Giuseppe Bertini
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Medicine, University of Verona, 37134 Verona, Italy
| | - Antonio R Artalejo
- Department of Pharmacology and Toxicology, Veterinary Faculty, Universidad Complutense de Madrid, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - Esteban Ballestar
- Epigenetics and Immune Disease Group, Josep Carreras Research Institute (IJC), 08916 Badalona, Barcelona, Spain; Epigenetics in Inflammatory and Metabolic Diseases Laboratory, Health Science Center (HSC), East China Normal University (ECNU), Shanghai 200241, China
| | - Annette Nicke
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Luis A Olivos-Oré
- Department of Pharmacology and Toxicology, Veterinary Faculty, Universidad Complutense de Madrid, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - Niamh M C Connolly
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - David C Henshall
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Tobias Engel
- Department of Physiology & Medical Physics, RCSI University of Medicine & Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.
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Dusing MR, LaSarge CL, Drake AW, Westerkamp GC, McCoy C, Hetzer SM, Kraus KL, Pedapati EV, Danzer SC. Transient Seizure Clusters and Epileptiform Activity Following Widespread Bilateral Hippocampal Interneuron Ablation. eNeuro 2024; 11:ENEURO.0317-23.2024. [PMID: 38575351 PMCID: PMC11036118 DOI: 10.1523/eneuro.0317-23.2024] [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: 08/02/2023] [Revised: 03/28/2024] [Accepted: 03/29/2024] [Indexed: 04/06/2024] Open
Abstract
Interneuron loss is a prominent feature of temporal lobe epilepsy in both animals and humans and is hypothesized to be critical for epileptogenesis. As loss occurs concurrently with numerous other potentially proepileptogenic changes, however, the impact of interneuron loss in isolation remains unclear. For the present study, we developed an intersectional genetic approach to induce bilateral diphtheria toxin-mediated deletion of Vgat-expressing interneurons from dorsal and ventral hippocampus. In a separate group of mice, the same population was targeted for transient neuronal silencing with DREADDs. Interneuron ablation produced dramatic seizure clusters and persistent epileptiform activity. Surprisingly, after 1 week seizure activity declined precipitously and persistent epileptiform activity disappeared. Occasional seizures (≈1/day) persisted to the end of the experiment at 4 weeks. In contrast to the dramatic impact of interneuron ablation, transient silencing produced large numbers of interictal spikes, a significant but modest increase in seizure occurrence and changes in EEG frequency band power. Taken together, findings suggest that the hippocampus regains relative homeostasis-with occasional breakthrough seizures-in the face of an extensive and abrupt loss of interneurons.
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Affiliation(s)
- Mary R Dusing
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
| | - Candi L LaSarge
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, Ohio 45229-3039
| | - Austin W Drake
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, Ohio 45229-3039
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039
| | - Grace C Westerkamp
- Division of Child Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
| | - Carlie McCoy
- Division of Neurosurgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
| | - Shelby M Hetzer
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, Ohio 45229-3039
| | - Kimberly L Kraus
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, Ohio 45229-3039
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039
| | - Ernest V Pedapati
- Division of Child Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
| | - Steve C Danzer
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, Ohio 45229-3039
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039
- Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039
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Stern MA, Cole ER, Gross RE, Berglund K. Seizure event detection using intravital two-photon calcium imaging data. NEUROPHOTONICS 2024; 11:024202. [PMID: 38274784 PMCID: PMC10809036 DOI: 10.1117/1.nph.11.2.024202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 12/20/2023] [Accepted: 12/26/2023] [Indexed: 01/27/2024]
Abstract
Significance Intravital cellular calcium imaging has emerged as a powerful tool to investigate how different types of neurons interact at the microcircuit level to produce seizure activity, with newfound potential to understand epilepsy. Although many methods exist to measure seizure-related activity in traditional electrophysiology, few yet exist for calcium imaging. Aim To demonstrate an automated algorithmic framework to detect seizure-related events using calcium imaging-including the detection of pre-ictal spike events, propagation of the seizure wavefront, and terminal spreading waves for both population-level activity and that of individual cells. Approach We developed an algorithm for precise recruitment detection of population and individual cells during seizure-associated events, which broadly leverages averaged population activity and high-magnitude slope features to detect single-cell pre-ictal spike and seizure recruitment. We applied this method to data recorded using awake in vivo two-photon calcium imaging during pentylenetetrazol-induced seizures in mice. Results We demonstrate that our detected recruitment times are concordant with visually identified labels provided by an expert reviewer and are sufficiently accurate to model the spatiotemporal progression of seizure-associated traveling waves. Conclusions Our algorithm enables accurate cell recruitment detection and will serve as a useful tool for researchers investigating seizure dynamics using calcium imaging.
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Affiliation(s)
- Matthew A. Stern
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, Georgia, United States
| | - Eric R. Cole
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, Georgia, United States
- Emory University, Georgia Institute of Technology, Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Robert E. Gross
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, Georgia, United States
- Emory University, Georgia Institute of Technology, Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Ken Berglund
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, Georgia, United States
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Takahashi K, Rensing NR, Eultgen EM, Wang SH, Nelvagal HR, Le SQ, Roberts MS, Doray B, Han EB, Dickson PI, Wong M, Sands MS, Cooper JD. GABAergic interneurons contribute to the fatal seizure phenotype of CLN2 disease mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.29.587276. [PMID: 38585903 PMCID: PMC10996664 DOI: 10.1101/2024.03.29.587276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
GABAergic interneuron deficits have been implicated in the epileptogenesis of multiple neurological diseases. While epileptic seizures are a key clinical hallmark of CLN2 disease, a childhood-onset neurodegenerative lysosomal storage disorder caused by a deficiency of tripeptidyl peptidase 1 (TPP1), the etiology of these seizures remains elusive. Given that Cln2 R207X/R207X mice display fatal spontaneous seizures and an early loss of several cortical interneuron populations, we hypothesized that those two events might be causally related. To address this hypothesis, we first generated an inducible transgenic mouse expressing lysosomal membrane-tethered TPP1 (TPP1LAMP1) on the Cln2 R207X/R207X genetic background to study the cell-autonomous effects of cell-type-specific TPP1 deficiency. We crossed the TPP1LAMP1 mice with Vgat-Cre mice to introduce interneuron-specific TPP1 deficiency. Vgat-Cre ; TPP1LAMP1 mice displayed storage material accumulation in several interneuron populations both in cortex and striatum, and increased susceptibility to die after PTZ-induced seizures. Secondly, to test the role of GABAergic interneuron activity in seizure progression, we selectively activated these cells in Cln2 R207X/R207X mice using Designer Receptor Exclusively Activated by Designer Drugs (DREADDs) in in Vgat-Cre : Cln2 R207X/R207X mice. EEG monitoring revealed that DREADD-mediated activation of interneurons via chronic deschloroclozapine administration accelerated the onset of spontaneous seizures and seizure-associated death in Vgat-Cre : Cln2 R207X/R207X mice, suggesting that modulating interneuron activity can exert influence over epileptiform abnormalities in CLN2 disease. Taken together, these results provide new mechanistic insights into the underlying etiology of seizures and premature death that characterize CLN2 disease.
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Shimoda Y, Leite M, Graham RT, Marvin JS, Hasseman J, Kolb I, Looger LL, Magloire V, Kullmann DM. Extracellular glutamate and GABA transients at the transition from interictal spiking to seizures. Brain 2024; 147:1011-1024. [PMID: 37787057 PMCID: PMC10907087 DOI: 10.1093/brain/awad336] [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: 05/10/2023] [Revised: 08/29/2023] [Accepted: 09/16/2023] [Indexed: 10/04/2023] Open
Abstract
Focal epilepsy is associated with intermittent brief population discharges (interictal spikes), which resemble sentinel spikes that often occur at the onset of seizures. Why interictal spikes self-terminate whilst seizures persist and propagate is incompletely understood. We used fluorescent glutamate and GABA sensors in an awake rodent model of neocortical seizures to resolve the spatiotemporal evolution of both neurotransmitters in the extracellular space. Interictal spikes were accompanied by brief glutamate transients which were maximal at the initiation site and rapidly propagated centrifugally. GABA transients lasted longer than glutamate transients and were maximal ∼1.5 mm from the focus where they propagated centripetally. Prior to seizure initiation GABA transients were attenuated, whilst glutamate transients increased, consistent with a progressive failure of local inhibitory restraint. As seizures increased in frequency, there was a gradual increase in the spatial extent of spike-associated glutamate transients associated with interictal spikes. Neurotransmitter imaging thus reveals a progressive collapse of an annulus of feed-forward GABA release, allowing seizures to escape from local inhibitory restraint.
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Affiliation(s)
- Yoshiteru Shimoda
- Department of Clinical & Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Marco Leite
- Department of Clinical & Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Robert T Graham
- Department of Clinical & Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Jonathan S Marvin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Jeremy Hasseman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Ilya Kolb
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Loren L Looger
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Vincent Magloire
- Department of Clinical & Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Dimitri M Kullmann
- Department of Clinical & Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
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Tsytsarev V, Sopova JV, Leonova EI, Inyushin M, Markina AA, Chirinskaite AV, Volnova AB. Neurophotonic methods in approach to in vivo animal epileptic models: Advantages and limitations. Epilepsia 2024; 65:600-614. [PMID: 38115808 PMCID: PMC10948300 DOI: 10.1111/epi.17870] [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: 07/18/2023] [Revised: 12/16/2023] [Accepted: 12/18/2023] [Indexed: 12/21/2023]
Abstract
Neurophotonic technology is a rapidly growing group of techniques that are based on the interactions of light with natural or genetically modified cells of the neural system. New optical technologies make it possible to considerably extend the tools of neurophysiological research, from the visualization of functional activity changes to control of brain tissue excitability. This opens new perspectives for studying the mechanisms underlying the development of human neurological diseases. Epilepsy is one of the most common brain disorders; it is characterized by recurrent seizures and affects >1% of the world's population. However, how seizures occur, spread, and terminate in a healthy brain is still unclear. Therefore, it is extremely important to develop appropriate models to accurately explore the causal relationship of epileptic activity. The use of neurophotonic technologies in epilepsy research falls into two broad categories: the visualization of neural epileptic activity, and the direct optical influence on neurons to induce or suppress epileptic activity. An optogenetic variant of the classical kindling model of epileptic seizures, in which activatable cells are genetically defined, is called optokindling. Research is also underway concerning the application of neurophotonic techniques for suppressing epileptic activity, aiming to bring these methods into clinical practice. This review aims to systematize and describe new approaches that use combinations of different neurophotonic methods to work with in vivo models of epilepsy. These approaches overcome many of the shortcomings associated with classical animal models of epilepsy and thus increase the effectiveness of developing new diagnostic methods and antiepileptic therapy.
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Affiliation(s)
- Vassiliy Tsytsarev
- University of Maryland School of Medicine, Department of Neurobiology 20 Penn St, HSF-2, 21201 MD, Baltimore, United States
| | - Julia V. Sopova
- Center of Transgenesis and Genome Editing, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Elena I. Leonova
- Center of Transgenesis and Genome Editing, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Mikhail Inyushin
- School of Medicine, Universidad Central del Caribe, Bayamon, PR 00956, USA
| | - Alisa A. Markina
- Institute of Translational Biomedicine, Saint Petersburg State University, St. Petersburg 199034, Russia
| | - Angelina V. Chirinskaite
- Center of Transgenesis and Genome Editing, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Anna B. Volnova
- Institute of Translational Biomedicine, Saint Petersburg State University, St. Petersburg 199034, Russia
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Stern MA, Dingledine R. One Ring to Bind Them: The Annulus of GABAergic Inhibitory Restraint Fades at Seizure Emergence. Epilepsy Curr 2024; 24:53-55. [PMID: 38327527 PMCID: PMC10846514 DOI: 10.1177/15357597231223586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024] Open
Abstract
Extracellular Glutamate and GABA Transients at the Transition From Interictal Spiking to Seizures Shimoda Y, Leite M, Graham RT, Marvin JS, Hasseman J, Kolb I, Looger LL, Magloire V, Kullmann DM. Brain . 2023: awad336. doi:10.1093/brain/awad336 Focal epilepsy is associated with intermittent brief population discharges (interictal spikes), which resemble sentinel spikes that often occur at the onset of seizures. Why interictal spikes self-terminate whilst seizures persist and propagate is incompletely understood. We used fluorescent glutamate and GABA sensors in an awake rodent model of neocortical seizures to resolve the spatiotemporal evolution of both neurotransmitters in the extracellular space. Interictal spikes were accompanied by brief glutamate transients which were maximal at the initiation site and rapidly propagated centrifugally. GABA transients lasted longer than glutamate transients and were maximal ∼1.5 mm from the focus where they propagated centripetally. Prior to seizure initiation GABA transients were attenuated, whilst glutamate transients increased, consistent with a progressive failure of local inhibitory restraint. As seizures increased in frequency, there was a gradual increase in the spatial extent of spike-associated glutamate transients associated with interictal spikes. Neurotransmitter imaging thus reveals a progressive collapse of an annulus of feed-forward GABA release, allowing seizures to escape from local inhibitory restraint.
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Affiliation(s)
- Matthew A Stern
- Department of Neurosurgery Emory University School of Medicine
| | - Raymond Dingledine
- Department of Pharmacology and Chemical Biology Emory University School of Medicine
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Choi T, Koo M, Joo J, Kim T, Shon YM, Park J. Bidirectional Neuronal Control of Epileptiform Activity by Repetitive Transcranial Focused Ultrasound Stimulations. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2302404. [PMID: 37997163 PMCID: PMC10787102 DOI: 10.1002/advs.202302404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 10/30/2023] [Indexed: 11/25/2023]
Abstract
Repetitive stimulation procedures are used in neuromodulation techniques to induce persistent excitatory or inhibitory brain activity. The directivity of modulation is empirically regulated by modifying the stimulation length, interval, and strength. However, bidirectional neuronal modulations using ultrasound stimulations are rarely reported. This study presents bidirectional control of epileptiform activities with repetitive transcranial-focused ultrasound stimulations in a rat model of drug-induced acute epilepsy. It is found that repeated transmission of elongated (40 s), ultra-low pressure (0.25 MPa) ultrasound can fully suppress epileptic activities in electro-encephalography and cerebral blood volume measurements, while the change in bursting intervals from 40 to 20 s worsens epileptic activities even with the same burst length. Furthermore, the suppression induced by 40 s long bursts is transformed to excitatory states by a subsequent transmission. Bidirectional modulation of epileptic seizures with repeated ultrasound stimulation is achieved by regulating the changes in glutamate and γ-Aminobutyric acid levels, as confirmed by measurements of expressed c-Fos and GAD65 and multitemporal analysis of neurotransmitters in the interstitial fluid obtained via microdialysis.
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Affiliation(s)
- Taewon Choi
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Minseok Koo
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Jaesoon Joo
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, Seoul, 06351, South Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, South Korea
| | - Taekyung Kim
- Biomedical Engineering Research Center, Samsung Medical Center, Seoul, 06351, South Korea
- Department of Medical Device Management and Research, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, Seoul, 06351, South Korea
| | - Young-Min Shon
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, Seoul, 06351, South Korea
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, South Korea
- Biomedical Engineering Research Center, Samsung Medical Center, Seoul, 06351, South Korea
- Department of Medical Device Management and Research, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, Seoul, 06351, South Korea
| | - Jinhyoung Park
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, 16419, South Korea
- Department of Biomedical Engineering, Sungkyunkwan University, Suwon, 16419, South Korea
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9
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Wenzel M, Huberfeld G, Grayden DB, de Curtis M, Trevelyan AJ. A debate on the neuronal origin of focal seizures. Epilepsia 2023; 64 Suppl 3:S37-S48. [PMID: 37183507 DOI: 10.1111/epi.17650] [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: 02/09/2023] [Revised: 04/26/2023] [Accepted: 05/12/2023] [Indexed: 05/16/2023]
Abstract
A critical question regarding how focal seizures start is whether we can identify particular cell classes that drive the pathological process. This was the topic for debate at the recent International Conference for Technology and Analysis of Seizures (ICTALS) meeting (July 2022, Bern, CH) that we summarize here. The debate has been fueled in recent times by the introduction of powerful new ways to manipulate subpopulations of cells in relative isolation, mostly using optogenetics. The motivation for resolving the debate is to identify novel targets for therapeutic interventions through a deeper understanding of the etiology of seizures.
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Affiliation(s)
- Michael Wenzel
- Department of Epileptology, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Gilles Huberfeld
- Neurology Department, Hopital Fondation Adolphe de Rothschild, Paris, France
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL, Paris, France
| | - David B Grayden
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Victoria, Australia
- Department of Medicine, St Vincent's Hospital, The University of Melbourne, Melbourne, Victoria, Australia
- Graeme Clark Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Marco de Curtis
- Epilepsy Unit, Fondazione I.R.C.C.S., Istituto Neurologico Carlo Besta, Milan, Italy
| | - Andrew J Trevelyan
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, UK
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10
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Stern MA, Cole ER, Gross RE, Berglund K. Seizure Event Detection Using Intravital Two-Photon Calcium Imaging Data. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.28.558338. [PMID: 37808822 PMCID: PMC10557641 DOI: 10.1101/2023.09.28.558338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Significance Genetic cellular calcium imaging has emerged as a powerful tool to investigate how different types of neurons interact at the microcircuit level to produce seizure activity, with newfound potential to understand epilepsy. Although many methods exist to measure seizure-related activity in traditional electrophysiology, few yet exist for calcium imaging. Aim To demonstrate an automated algorithmic framework to detect seizure-related events using calcium imaging - including the detection of pre-ictal spike events, propagation of the seizure wavefront, and terminal spreading waves for both population-level activity and that of individual cells. Approach We developed an algorithm for precise recruitment detection of population and individual cells during seizure-associated events, which broadly leverages averaged population activity and high-magnitude slope features to detect single-cell pre-ictal spike and seizure recruitment. We applied this method to data recorded using awake in vivo two-photon calcium imaging during pentylenetetrazol induced seizures in mice. Results We demonstrate that our detected recruitment times are concordant with visually identified labels provided by an expert reviewer and are sufficiently accurate to model the spatiotemporal progression of seizure-associated traveling waves. Conclusions Our algorithm enables accurate cell recruitment detection and will serve as a useful tool for researchers investigating seizure dynamics using calcium imaging.
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Affiliation(s)
- Matthew A. Stern
- Authors Contributed Equally
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, GA, United States
| | - Eric R. Cole
- Authors Contributed Equally
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, GA, United States
- Emory University and Georgia Institute of Technology, Coulter Department of Biomedical Engineering, Atlanta, GA, United States
| | - Robert E. Gross
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, GA, United States
- Emory University and Georgia Institute of Technology, Coulter Department of Biomedical Engineering, Atlanta, GA, United States
| | - Ken Berglund
- Emory University School of Medicine, Department of Neurosurgery, Atlanta, GA, United States
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11
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Zhao J, Yu Y, Han F, Wang Q. Regulating epileptiform discharges by heterogeneous interneurons in thalamocortical model. CHAOS (WOODBURY, N.Y.) 2023; 33:083128. [PMID: 37561121 DOI: 10.1063/5.0163243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 07/25/2023] [Indexed: 08/11/2023]
Abstract
Inhibitory interneurons in the cortex are abundant and have diverse roles, classified as parvalbumin (PV), somatostatin (SOM), and vasoactive intestinal polypeptide (VIP) according to chemically defined categories. Currently, their involvement with seizures has been partially uncovered in physiological terms. Here, we propose a corticothalamic model containing heterogeneous interneurons to study the effects of various interneurons on absence seizure dynamics by means of optogenetic stimulation. First, the important role of feedforward inhibition caused by SRN→PV→PN projections on seizures is verified. Then, we demonstrate that light activation targeting either PV or SOM INs can control seizures. Finally, with different inhibition contributions from PV INs and SOM INs, the possible disinhibitory effect of blue light acting on VIP INs is mainly discussed. The results suggest that depending on the inhibition degree of both types, the disinhibition brought about by the VIP INs will trigger seizures, will control seizures, and will not work or cause the PNs to tend toward a high saturation state with high excitability. The circuit mechanism and the related bifurcation characteristics in various cases are emphatically revealed. In the model presented, in addition to Hopf and saddle-node bifurcations, the system may also undergo period-doubling and torus bifurcations under stimulus action, with more complex dynamics. Our work may provide a theoretical basis for understanding and further exploring the role of heterogeneous interneurons, in particular, the VIP INs, a novel target, in absence seizures.
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Affiliation(s)
- Jinyi Zhao
- Department of Dynamics and Control, Beihang University, Beijing 100191, China
| | - Ying Yu
- School of Engineering Medicine, Beihang University, Beijing 100191, China
| | - Fang Han
- College of Information Science and Technology, Donghua University, Shanghai 201620, China
| | - Qingyun Wang
- Department of Dynamics and Control, Beihang University, Beijing 100191, China
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12
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Giustizieri M, Petrillo S, D’Amico J, Torda C, Quatrana A, Vigevano F, Specchio N, Piemonte F, Cherubini E. The ferroptosis inducer RSL3 triggers interictal epileptiform activity in mice cortical neurons. Front Cell Neurosci 2023; 17:1213732. [PMID: 37396923 PMCID: PMC10311487 DOI: 10.3389/fncel.2023.1213732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 05/31/2023] [Indexed: 07/04/2023] Open
Abstract
Epilepsy is a neurological disorder characterized by recurrent seizures, which result from excessive, synchronous discharges of neurons in different brain areas. In about 30% of cases, epileptic discharges, which vary in their etiology and symptomatology, are difficult to treat with conventional drugs. Ferroptosis is a newly defined iron-dependent programmed cell death, characterized by excessive accumulation of lipid peroxides and reactive oxygen species. Evidence has been provided that ferroptosis is involved in epilepsy, and in particular in those forms resistant to drugs. Here, whole cell patch clamp recordings, in current and voltage clamp configurations, were performed from layer IV principal neurons in cortical slices obtained from adult mouse brain. Application of the ferroptosis inducer RAS-selective lethal 3 (RSL3) induced interictal epileptiform discharges which started at RSL3 concentrations of 2 μM and reached a plateau at 10 μM. This effect was not due to changes in active or passive membrane properties of the cells, but relied on alterations in synaptic transmission. In particular, interictal discharges were dependent on the excessive excitatory drive to layer IV principal cells, as suggested by the increase in frequency and amplitude of spontaneously occurring excitatory glutamatergic currents, possibly dependent on the reduction of inhibitory GABAergic ones. This led to an excitatory/inhibitory unbalance in cortical circuits. Interictal bursts could be prevented or reduced in frequency by the lipophilic antioxidant Vitamin E (30 μM). This study allows identifying new targets of ferroptosis-mediated epileptic discharges opening new avenues for the treatment of drug-resistant forms of epilepsy.
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Affiliation(s)
- Michela Giustizieri
- European Brain Research Institute (EBRI)-Rita Levi-Montalcini Foundation, Rome, Italy
| | - Sara Petrillo
- Muscular and Neurodegenerative Diseases Laboratory, Research Area of Neurological Sciences and Rehabilitation Medicine, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Jessica D’Amico
- Muscular and Neurodegenerative Diseases Laboratory, Research Area of Neurological Sciences and Rehabilitation Medicine, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Caterina Torda
- Muscular and Neurodegenerative Diseases Laboratory, Research Area of Neurological Sciences and Rehabilitation Medicine, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Andrea Quatrana
- Muscular and Neurodegenerative Diseases Laboratory, Research Area of Neurological Sciences and Rehabilitation Medicine, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Federico Vigevano
- Neurology Unit, Research Area of Neurological Sciences and Rehabilitation Medicine, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Nicola Specchio
- Clinical and Experimental Neurology, Bambino Gesù Children’s Hospital, IRCCS, Full Member of European Reference Network on Rare and Complex Epilepsies (EpiCARE), Rome, Italy
| | - Fiorella Piemonte
- Muscular and Neurodegenerative Diseases Laboratory, Research Area of Neurological Sciences and Rehabilitation Medicine, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Enrico Cherubini
- European Brain Research Institute (EBRI)-Rita Levi-Montalcini Foundation, Rome, Italy
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13
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Carvalho-Rosa JD, Rodrigues NC, Silva-Cruz A, Vaz SH, Cunha-Reis D. Epileptiform activity influences theta-burst induced LTP in the adult hippocampus: a role for synaptic lipid raft disruption in early metaplasticity? Front Cell Neurosci 2023; 17:1117697. [PMID: 37228704 PMCID: PMC10203237 DOI: 10.3389/fncel.2023.1117697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 04/13/2023] [Indexed: 05/27/2023] Open
Abstract
Non-epileptic seizures are identified as a common epileptogenic trigger. Early metaplasticity following seizures may contribute to epileptogenesis by abnormally altering synaptic strength and homeostatic plasticity. We now studied how in vitro epileptiform activity (EA) triggers early changes in CA1 long-term potentiation (LTP) induced by theta-burst stimulation (TBS) in rat hippocampal slices and the involvement of lipid rafts in these early metaplasticity events. Two forms of EA were induced: (1) interictal-like EA evoked by Mg2+ withdrawal and K+ elevation to 6 mM in the superfusion medium or (2) ictal-like EA induced by bicuculline (10 μM). Both EA patterns induced and LTP-like effect on CA1 synaptic transmission prior to LTP induction. LTP induced 30 min post EA was impaired, an effect more pronounced after ictal-like EA. LTP recovered to control levels 60 min post interictal-like EA but was still impaired 60 min after ictal-like EA. The synaptic molecular events underlying this altered LTP were investigated 30 min post EA in synaptosomes isolated from these slices. EA enhanced AMPA GluA1 Ser831 phosphorylation but decreased Ser845 phosphorylation and the GluA1/GluA2 ratio. Flotillin-1 and caveolin-1 were markedly decreased concomitantly with a marked increase in gephyrin levels and a less prominent increase in PSD-95. Altogether, EA differentially influences hippocampal CA1 LTP thorough regulation of GluA1/GluA2 levels and AMPA GluA1 phosphorylation suggesting that altered LTP post-seizures is a relevant target for antiepileptogenic therapies. In addition, this metaplasticity is also associated with marked alterations in classic and synaptic lipid raft markers, suggesting these may also constitute promising targets in epileptogenesis prevention.
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Affiliation(s)
- José D. Carvalho-Rosa
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- BioISI–Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Nádia C. Rodrigues
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Armando Silva-Cruz
- BioISI–Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Sandra H. Vaz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
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14
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Kritzer MD, Peterchev AV, Camprodon JA. Electroconvulsive Therapy: Mechanisms of Action, Clinical Considerations, and Future Directions. Harv Rev Psychiatry 2023; 31:101-113. [PMID: 37171471 PMCID: PMC10198476 DOI: 10.1097/hrp.0000000000000365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
LEARNING OBJECTIVES • Outline and discuss the fundamental physiologic, cellular, and molecular mechanisms of ECT to devise strategies to optimize therapeutic outcomes• Summarize the overview of ECT, its efficacy in treating depression, the known effects on cognition, evidence of mechanisms, and future directions. ABSTRACT Electroconvulsive therapy (ECT) is the most effective treatment for a variety of psychiatric illnesses, including treatment-resistant depression, bipolar depression, mania, catatonia, and clozapine-resistant schizophrenia. ECT is a medical and psychiatric procedure whereby electrical current is delivered to the brain under general anesthesia to induce a generalized seizure. ECT has evolved a great deal since the 1930s. Though it has been optimized for safety and to reduce adverse effects on cognition, issues persist. There is a need to understand fundamental physiologic, cellular, and molecular mechanisms of ECT to devise strategies to optimize therapeutic outcomes. Clinical trials that set out to adjust parameters, electrode placement, adjunctive medications, and patient selection are critical steps towards the goal of improving outcomes with ECT. This narrative review provides an overview of ECT, its efficacy in treating depression, its known effects on cognition, evidence of its mechanisms, and future directions.
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Affiliation(s)
- Michael D Kritzer
- From the Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA (Drs. Kritzer, Camprodon); Department of Psychiatry and Behavioral Sciences, Department of Biomedical Engineering, Department of Electrical and Computer Engineering, Department of Neurosurgery, Duke University, Durham, NC (Dr. Peterchev)
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15
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Magloire V, Savtchenko LP, Jensen TP, Sylantyev S, Kopach O, Cole N, Tyurikova O, Kullmann DM, Walker MC, Marvin JS, Looger LL, Hasseman JP, Kolb I, Pavlov I, Rusakov DA. Volume-transmitted GABA waves pace epileptiform rhythms in the hippocampal network. Curr Biol 2023; 33:1249-1264.e7. [PMID: 36921605 PMCID: PMC10615848 DOI: 10.1016/j.cub.2023.02.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 01/05/2023] [Accepted: 02/15/2023] [Indexed: 03/17/2023]
Abstract
Mechanisms that entrain and pace rhythmic epileptiform discharges remain debated. Traditionally, the quest to understand them has focused on interneuronal networks driven by synaptic GABAergic connections. However, synchronized interneuronal discharges could also trigger the transient elevations of extracellular GABA across the tissue volume, thus raising tonic conductance (Gtonic) of synaptic and extrasynaptic GABA receptors in multiple cells. Here, we monitor extracellular GABA in hippocampal slices using patch-clamp GABA "sniffer" and a novel optical GABA sensor, showing that periodic epileptiform discharges are preceded by transient, region-wide waves of extracellular GABA. Neural network simulations that incorporate volume-transmitted GABA signals point to a cycle of GABA-driven network inhibition and disinhibition underpinning this relationship. We test and validate this hypothesis using simultaneous patch-clamp recordings from multiple neurons and selective optogenetic stimulation of fast-spiking interneurons. Critically, reducing GABA uptake in order to decelerate extracellular GABA fluctuations-without affecting synaptic GABAergic transmission or resting GABA levels-slows down rhythmic activity. Our findings thus unveil a key role of extrasynaptic, volume-transmitted GABA in pacing regenerative rhythmic activity in brain networks.
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Affiliation(s)
- Vincent Magloire
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
| | - Leonid P Savtchenko
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
| | - Thomas P Jensen
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Sergyi Sylantyev
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; Rowett Institute, University of Aberdeen, Ashgrove Road West, Aberdeen AB25 2ZD, UK
| | - Olga Kopach
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Nicholas Cole
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Olga Tyurikova
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Dimitri M Kullmann
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Matthew C Walker
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Jonathan S Marvin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Loren L Looger
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA; GENIE Project Team, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Jeremy P Hasseman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; GENIE Project Team, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Ilya Kolb
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; GENIE Project Team, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Ivan Pavlov
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Dmitri A Rusakov
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
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16
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Zaaimi B, Turnbull M, Hazra A, Wang Y, Gandara C, McLeod F, McDermott EE, Escobedo-Cousin E, Idil AS, Bailey RG, Tardio S, Patel A, Ponon N, Gausden J, Walsh D, Hutchings F, Kaiser M, Cunningham MO, Clowry GJ, LeBeau FEN, Constandinou TG, Baker SN, Donaldson N, Degenaar P, O'Neill A, Trevelyan AJ, Jackson A. Closed-loop optogenetic control of the dynamics of neural activity in non-human primates. Nat Biomed Eng 2023; 7:559-575. [PMID: 36266536 PMCID: PMC7614485 DOI: 10.1038/s41551-022-00945-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 08/14/2022] [Indexed: 11/08/2022]
Abstract
Electrical neurostimulation is effective in the treatment of neurological disorders, but associated recording artefacts generally limit its applications to open-loop stimuli. Real-time and continuous closed-loop control of brain activity can, however, be achieved by pairing concurrent electrical recordings and optogenetics. Here we show that closed-loop optogenetic stimulation with excitatory opsins enables the precise manipulation of neural dynamics in brain slices from transgenic mice and in anaesthetized non-human primates. The approach generates oscillations in quiescent tissue, enhances or suppresses endogenous patterns in active tissue and modulates seizure-like bursts elicited by the convulsant 4-aminopyridine. A nonlinear model of the phase-dependent effects of optical stimulation reproduced the modulation of cycles of local-field potentials associated with seizure oscillations, as evidenced by the systematic changes in the variability and entropy of the phase-space trajectories of seizures, which correlated with changes in their duration and intensity. We also show that closed-loop optogenetic neurostimulation could be delivered using intracortical optrodes incorporating light-emitting diodes. Closed-loop optogenetic approaches may be translatable to therapeutic applications in humans.
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Affiliation(s)
- B Zaaimi
- Biosciences Institute, Newcastle University, Newcastle, UK
- School of Life and Health Sciences, Aston University, Birmingham, UK
| | - M Turnbull
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - A Hazra
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - Y Wang
- School of Computing, Newcastle University, Newcastle, UK
| | - C Gandara
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - F McLeod
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - E E McDermott
- Biosciences Institute, Newcastle University, Newcastle, UK
| | | | - A Shah Idil
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - R G Bailey
- School of Engineering, Newcastle University, Newcastle, UK
| | - S Tardio
- School of Engineering, Newcastle University, Newcastle, UK
| | - A Patel
- School of Engineering, Newcastle University, Newcastle, UK
| | - N Ponon
- School of Engineering, Newcastle University, Newcastle, UK
| | - J Gausden
- School of Engineering, Newcastle University, Newcastle, UK
| | - D Walsh
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - F Hutchings
- School of Computing, Newcastle University, Newcastle, UK
| | - M Kaiser
- School of Computing, Newcastle University, Newcastle, UK
- NIHR, Nottingham Biomedical Research Centre, School of Medicine, University of Nottingham, Nottingham, UK
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, UK
- Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - M O Cunningham
- School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - G J Clowry
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - F E N LeBeau
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - T G Constandinou
- Department of Electrical and Electronic Engineering, Imperial College, London, UK
| | - S N Baker
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - N Donaldson
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - P Degenaar
- School of Engineering, Newcastle University, Newcastle, UK
| | - A O'Neill
- School of Engineering, Newcastle University, Newcastle, UK
| | - A J Trevelyan
- Biosciences Institute, Newcastle University, Newcastle, UK
| | - A Jackson
- Biosciences Institute, Newcastle University, Newcastle, UK.
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17
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Vasilopoulos N, Kaplanian A, Vinos M, Katsaiti Y, Christodoulou O, Denaxa M, Skaliora I. The role of selective SATB1 deletion in somatostatin expressing interneurons on endogenous network activity and the transition to epilepsy. J Neurosci Res 2023; 101:424-447. [PMID: 36541427 DOI: 10.1002/jnr.25156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 10/24/2022] [Accepted: 12/03/2022] [Indexed: 12/24/2022]
Abstract
Somatostatin (SST) expressing interneurons are the second most abundant group of inhibitory neurons in the neocortex. They mainly target the apical dendrites of excitatory pyramidal cells and are implicated in feedforward and feedback inhibition. In the present study, we employ a conditional knockout mouse, in which the transcription factor Satb1 is selectively deleted in SST-expressing interneurons resulting to the reduction of their number across the somatosensory barrel field. Our goal was to investigate the effect of the reduced number of Satb1 mutant SST-interneurons on (i) the endogenous cortical network activity (spontaneously recurring Up/Down states), and (ii) the transition to epileptiform activity. By conducting LFP recordings in acute brain slices from young male and female mice, we demonstrate that mutant animals exhibit significant changes in network excitability, reflected in increased Up state occurrence, decreased Up state duration and higher levels of extracellular spiking activity. Epileptiform activity was induced through two distinct and widely used in vitro protocols: the low magnesium and the 4-Aminopyridine (4-AP) model. In the former, slices from mutant animals manifested shorter latency for the expression of stable seizure-like events. In contrast, when epilepsy was induced by 4-AP, no significant differences were reported. We conclude that normal SST-interneuron function has a significant role both in the regulation of the endogenous network activity, and in the transition to seizure-like discharges in a context-dependent manner.
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Affiliation(s)
- Nikos Vasilopoulos
- Centre for Basic Research, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece
| | - Ani Kaplanian
- Centre for Basic Research, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece
| | - Michael Vinos
- Centre for Basic Research, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece.,Department of History and Philosophy of Science, National and Kapodistrian University of Athens (NKUA), Athens, Greece
| | - Yolanda Katsaiti
- Biomedical Sciences Research Center "Alexander Fleming", Vari, Greece.,Department of Biology, National and Kapodistrian University of Athens (NKUA), Athens, Greece
| | - Ourania Christodoulou
- Biomedical Sciences Research Center "Alexander Fleming", Vari, Greece.,Department of Biology, University of Crete, Heraklion, Greece
| | - Myrto Denaxa
- Biomedical Sciences Research Center "Alexander Fleming", Vari, Greece
| | - Irini Skaliora
- Centre for Basic Research, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece.,Department of History and Philosophy of Science, National and Kapodistrian University of Athens (NKUA), Athens, Greece
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18
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Chen W, Man X, Zhang Y, Yao G, Chen J. Medial prefrontal cortex oxytocin mitigates epilepsy and cognitive impairments induced by traumatic brain injury through reducing neuroinflammation in mice. Sci Rep 2023; 13:5214. [PMID: 36997619 PMCID: PMC10063625 DOI: 10.1038/s41598-023-32351-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 03/26/2023] [Indexed: 04/01/2023] Open
Abstract
Traumatic brain injury (TBI) is a major risk factor to develop epilepsy and cognitive impairments. Neuropeptide oxytocin has been previously evidenced to produce antiepileptic effects. However, the involvement of central oxytocin in TBI-induced epileptic status and cognitive dysfunctions is not fully elucidated. In this study, we aim to investigate the role of oxytocin on a TBI model followed by seizure induction to clarify whether the epilepsy and cognitive deficits could be mitigated by oxytocin. TBI was established by weight drop and epileptic behaviors were induced by pentylenetetrazole (PTZ) injection in mice. Moreover, oxytocin was microinjected into the medial prefrontal cortex (mPFC) to observe the effects on the epilepsy and cognition. The blood-brain barrier (BBB) function and the neuroinflammation were measured by Evans Blue staining and enzyme-linked immunosorbent assays, respectively. Mice exposed to TBI demonstrate increased vulnerability to PTZ-mediated seizures and cognitive disturbances with a decrease in peripheral and brain oxytocin levels. Additionally, TBI reduces oxytocin, disrupts the BBB permeability and triggers neuroinflammation in mPFC in PTZ-treated mice. Intra-mPFC oxytocin simultaneously mitigates epilepsy and cognitive impairments. Finally, oxytocin restores BBB integrity and reduces mPFC inflammation in PTZ-treated TBI mice. These findings showed that intra-mPFC oxytocin suppressed the seizure vulnerability and cognitive deficits in TBI mice. The normalization of BBB integrity and inhibition of neuroinflammation may be involved in the antiepileptic and cognition-improved effects of oxytocin, suggesting that targeting inflammatory procedure in mPFC may decrease the risk to develop epilepsy and cognitive impairments in individuals previously experienced TBI.
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Affiliation(s)
- Wen Chen
- Department of Neurology, Central Hospital Affiliated to Shandong First Medical University, 105 Jiefang Rd, Lixia District, Jinan, 250013, Shandong, China.
| | - Xiaoxiao Man
- Department of Neurology, Central Hospital Affiliated to Shandong First Medical University, 105 Jiefang Rd, Lixia District, Jinan, 250013, Shandong, China
| | - Yu Zhang
- Department of Neurology, Central Hospital Affiliated to Shandong First Medical University, 105 Jiefang Rd, Lixia District, Jinan, 250013, Shandong, China
| | - Guangyan Yao
- Department of Neurology, Central Hospital Affiliated to Shandong First Medical University, 105 Jiefang Rd, Lixia District, Jinan, 250013, Shandong, China
| | - Jing Chen
- Department of Neurology, Central Hospital Affiliated to Shandong First Medical University, 105 Jiefang Rd, Lixia District, Jinan, 250013, Shandong, China
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19
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Sack AS. Adult-Born Granule Cells Contribute to Dentate Gyrus Circuit Reorganization after Traumatic Brain Injury. J Neurosci 2023; 43:879-881. [PMID: 36754637 PMCID: PMC9908312 DOI: 10.1523/jneurosci.1994-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 12/10/2022] [Accepted: 12/12/2022] [Indexed: 02/10/2023] Open
Affiliation(s)
- Anne-Sophie Sack
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
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20
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Bryson A, Reid C, Petrou S. Fundamental Neurochemistry Review: GABA A receptor neurotransmission and epilepsy: Principles, disease mechanisms and pharmacotherapy. J Neurochem 2023; 165:6-28. [PMID: 36681890 DOI: 10.1111/jnc.15769] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/12/2022] [Accepted: 01/04/2023] [Indexed: 01/23/2023]
Abstract
Epilepsy is a common neurological disorder associated with alterations of excitation-inhibition balance within brain neuronal networks. GABAA receptor neurotransmission is the most prevalent form of inhibitory neurotransmission and is strongly implicated in both the pathophysiology and treatment of epilepsy, serving as a primary target for antiseizure medications for over a century. It is now established that GABA exerts a multifaceted influence through an array of GABAA receptor subtypes that extends far beyond simply negating excitatory activity. As the role of GABAA neurotransmission within inhibitory circuits is elaborated, this will enable the development of precision therapies that correct the network dysfunction underlying epileptic pathology.
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Affiliation(s)
- Alexander Bryson
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
| | - Christopher Reid
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.,Praxis Precision Medicines, Inc., Cambridge, Massachusetts, USA
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21
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Bryson A, Petrou S. SCN1A channelopathies: Navigating from genotype to neural circuit dysfunction. Front Neurol 2023; 14:1173460. [PMID: 37139072 PMCID: PMC10149698 DOI: 10.3389/fneur.2023.1173460] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 03/28/2023] [Indexed: 05/05/2023] Open
Abstract
The SCN1A gene is strongly associated with epilepsy and plays a central role for supporting cortical excitation-inhibition balance through the expression of NaV1.1 within inhibitory interneurons. The phenotype of SCN1A disorders has been conceptualized as driven primarily by impaired interneuron function that predisposes to disinhibition and cortical hyperexcitability. However, recent studies have identified SCN1A gain-of-function variants associated with epilepsy, and the presence of cellular and synaptic changes in mouse models that point toward homeostatic adaptations and complex network remodeling. These findings highlight the need to understand microcircuit-scale dysfunction in SCN1A disorders to contextualize genetic and cellular disease mechanisms. Targeting the restoration of microcircuit properties may be a fruitful strategy for the development of novel therapies.
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Affiliation(s)
- Alexander Bryson
- Ion Channels and Disease Group, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
- *Correspondence: Alexander Bryson,
| | - Steven Petrou
- Ion Channels and Disease Group, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
- Praxis Precision Medicines, Inc., Cambridge, MA, United States
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22
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Trevelyan AJ, Graham RT, Parrish RR, Codadu NK. Synergistic Positive Feedback Mechanisms Underlying Seizure Initiation. Epilepsy Curr 2023; 23:38-43. [PMID: 36923333 PMCID: PMC10009126 DOI: 10.1177/15357597221127163] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Investigations into seizure initiation, in recent years, have focused almost entirely upon alterations of interneuronal function, chloride homeostasis, and extracellular potassium levels. In contrast, little attention has been directed toward a possible role of dendritic plateau potentials in the actual ictogenic transition, despite a substantial literature dating back 40 years regarding its importance generally in epilepsy. Here, we argue that an increase in dendritic excitability, coordinated across the population of pyramidal cells, is a key stage in ictogenesis.
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Affiliation(s)
- Andrew J. Trevelyan
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, United Kingdom
| | - Robert T. Graham
- Queen Square Institute of Neurology, University College London, United Kingdom
| | - R. Ryley Parrish
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT, USA
| | - Neela K. Codadu
- Queen Square Institute of Neurology, University College London, United Kingdom
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23
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Proskurina EY, Chizhov AV, Zaitsev AV. Optogenetic Low-Frequency Stimulation of Principal Neurons, but Not Parvalbumin-Positive Interneurons, Prevents Generation of Ictal Discharges in Rodent Entorhinal Cortex in an In Vitro 4-Aminopyridine Model. Int J Mol Sci 2022; 24:ijms24010195. [PMID: 36613660 PMCID: PMC9820186 DOI: 10.3390/ijms24010195] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/17/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Low-frequency electrical stimulation is used to treat some drug-resistant forms of epilepsy. Despite the effectiveness of the method in suppressing seizures, there is a considerable risk of side effects. An optogenetic approach allows the targeting of specific populations of neurons, which can increase the effectiveness and safety of low-frequency stimulation. In our study, we tested the efficacy of the suppression of ictal activity in entorhinal cortex slices in a 4-aminopyridine model with three variants of low-frequency light stimulation (LFLS): (1) activation of excitatory and inhibitory neurons (on Thy1-ChR2-YFP mice), (2) activation of inhibitory interneurons only (on PV-Cre mice after virus injection with channelrhodopsin2 gene), and (3) hyperpolarization of excitatory neurons (on Wistar rats after virus injection with archaerhodopsin gene). Only in the first variant did simultaneous LFLS of excitatory and inhibitory neurons replace ictal activity with interictal activity. We suggest that LFLS caused changes in the concentration gradients of K+ and Na+ cations across the neuron membrane, which activated Na-K pumping. According to the mathematical modeling, the increase in Na-K pump activity in neurons induced by LFLS led to an antiepileptic effect. Thus, a less specific and generalized optogenetic effect on entorhinal cortex neurons was more effective in suppressing ictal activity in the 4-aminopyridine model.
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Affiliation(s)
- Elena Y. Proskurina
- Almazov National Medical Research Centre, 2 Akkuratova Street, 197341 St. Petersburg, Russia
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, 44 Toreza Prospekt, 194223 St. Petersburg, Russia
| | - Anton V. Chizhov
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, 44 Toreza Prospekt, 194223 St. Petersburg, Russia
- Computational Physics Laboratory, Ioffe Institute, 26 Polytekhnicheskaya Street, 194021 St. Petersburg, Russia
- MathNeuro Team, Inria Centre at Universite Cote d’Azur, 06902 Sophia Antipolis, France
| | - Aleksey V. Zaitsev
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, 44 Toreza Prospekt, 194223 St. Petersburg, Russia
- Correspondence:
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24
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Zhang H, Shen Z, Zhao Y, Du L, Deng Z. Dynamical Mechanism Analysis of Three Neuroregulatory Strategies on the Modulation of Seizures. Int J Mol Sci 2022; 23:13652. [PMID: 36362443 PMCID: PMC9657301 DOI: 10.3390/ijms232113652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/30/2022] [Accepted: 11/02/2022] [Indexed: 08/11/2023] Open
Abstract
This paper attempts to explore and compare the regulatory mechanisms of optogenetic stimulation (OS), deep brain stimulation (DBS) and electromagnetic induction on epilepsy. Based on the Wilson-Cowan model, we first demonstrate that the external input received by excitatory and inhibitory neural populations can induce rich dynamic bifurcation behaviors such as Hopf bifurcation, and make the system exhibit epileptic and normal states. Then, both OS and DBS are shown to be effective in controlling the epileptic state to a normal low-level state, and the stimulus parameters have a broad effective range. However, electromagnetic induction cannot directly control epilepsy to this desired state, even if it can significantly reduce the oscillation frequency of neural populations. One main difference worth noting is that the high spatiotemporal specificity of OS allows it to target inhibitory neuronal populations, whereas DBS and electromagnetic induction can only stimulate excitatory as well as inhibitory neuronal populations together. Next, the propagation behavior of epilepsy is explored under a typical three-node feedback loop structure. An increase in coupling strength accelerates and exacerbates epileptic activity in other brain regions. Finally, OS and DBS applied to the epileptic focus play similar positive roles in controlling the behavior of the area of seizure propagation, while electromagnetic induction still only achieves unsatisfactory effects. It is hoped that these dynamical results can provide insights into the treatment of epilepsy as well as other neurological disorders.
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Affiliation(s)
- Honghui Zhang
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710072, China
- MIIT Key Laboratory of Dynamics and Control of Complex Systems, Xi’an 710072, China
| | - Zhuan Shen
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710072, China
- MIIT Key Laboratory of Dynamics and Control of Complex Systems, Xi’an 710072, China
| | - Yuzhi Zhao
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710072, China
- MIIT Key Laboratory of Dynamics and Control of Complex Systems, Xi’an 710072, China
| | - Lin Du
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710072, China
- MIIT Key Laboratory of Dynamics and Control of Complex Systems, Xi’an 710072, China
| | - Zichen Deng
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710072, China
- MIIT Key Laboratory of Dynamics and Control of Complex Systems, Xi’an 710072, China
- School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China
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25
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Thouta S, Waldbrook MG, Lin S, Mahadevan A, Mezeyova J, Soriano M, Versi P, Goodchild SJ, Parrish RR. Pharmacological determination of the fractional block of Nav channels required to impair neuronal excitability and ex vivo seizures. Front Cell Neurosci 2022; 16:964691. [PMID: 36246527 PMCID: PMC9557217 DOI: 10.3389/fncel.2022.964691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
Voltage-gated sodium channels (Nav) are essential for the initiation and propagation of action potentials in neurons. Of the nine human channel subtypes, Nav1.1, Nav1.2 and Nav1.6 are prominently expressed in the adult central nervous system (CNS). All three of these sodium channel subtypes are sensitive to block by the neurotoxin tetrodotoxin (TTX), with TTX being almost equipotent on all three subtypes. In the present study we have used TTX to determine the fractional block of Nav channels required to impair action potential firing in pyramidal neurons and reduce network seizure-like activity. Using automated patch-clamp electrophysiology, we first determined the IC50s of TTX on mouse Nav1.1, Nav1.2 and Nav1.6 channels expressed in HEK cells, demonstrating this to be consistent with previously published data on human orthologs. We then compared this data to the potency of block of Nav current measured in pyramidal neurons from neocortical brain slices. Interestingly, we found that it requires nearly 10-fold greater concentration of TTX over the IC50 to induce significant block of action potentials using a current-step protocol. In contrast, concentrations near the IC50 resulted in a significant reduction in AP firing and increase in rheobase using a ramp protocol. Surprisingly, a 20% reduction in action potential generation observed with 3 nM TTX resulted in significant block of seizure-like activity in the 0 Mg2+ model of epilepsy. Additionally, we found that approximately 50% block in pyramidal cell intrinsic excitability is sufficient to completely block all seizure-like events. Furthermore, we also show that the anticonvulsant drug phenytoin blocked seizure-like events in a manner similar to TTX. These data serve as a critical starting point in understanding how fractional block of Nav channels affect intrinsic neuronal excitability and seizure-like activity. It further suggests that seizures can be controlled without significantly compromising intrinsic neuronal activity and determines the required fold over IC50 for novel and clinically relevant Nav channel blockers to produce efficacy and limit side effects.
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Affiliation(s)
- Samrat Thouta
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Matthew G. Waldbrook
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Sophia Lin
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Arjun Mahadevan
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Janette Mezeyova
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Maegan Soriano
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Pareesa Versi
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - Samuel J. Goodchild
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
| | - R. Ryley Parrish
- Department of Cellular and Molecular Biology, Xenon Pharmaceuticals Inc., Burnaby, BC, Canada
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT, United States
- *Correspondence: R. Ryley Parrish,
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26
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Proskurina EY, Zaitsev AV. Regulation of Potassium and Chloride Concentrations in Nervous Tissue as a Method of Anticonvulsant Therapy. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022050015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Abstract
Under some pathological conditions, such as pharmacoresistant
epilepsy, status epilepticus or certain forms of genetic abnormalities,
spiking activity of GABAergic interneurons may enhance excitation
processes in neuronal circuits and provoke the generation of ictal
discharges. As a result, anticonvulsants acting on the GABAergic
system may be ineffective or even increase seizure activity. This
paradoxical effect of the inhibitory system is due to ionic imbalances
in nervous tissue. This review addresses the mechanisms of ictal
discharge initiation in neuronal networks due to the imbalance of
chloride and potassium ions, as well as possible ways to regulate
ionic concentrations. Both the enhancement (or attenuation) of the
activity of certain neuronal ion transporters and ion pumps and
their additional expression via gene therapy can be effective in
suppressing seizure activity caused by ionic imbalances. The Na+–K+-pump,
NKCC1 and KCC2 cotransporters are important for maintaining proper
K+ and Cl– concentrations
in nervous tissue, having been repeatedly considered as pharmacological
targets for antiepileptic exposures. Further progress in this direction
is hampered by the lack of sufficiently selective pharmacological
tools and methods for providing effective drug delivery to the epileptic
focus. The use of the gene therapy techniques, such as overexpressing
of the KCC2 transporter in the epileptic focus, seems to be a more promising
approach. Another possible direction could be the use of optogenetic
tools, namely specially designed light-activated ion pumps or ion
channels. In this case, photon energy can be used to create the
required gradients of chloride and potassium ions, although these
methods also have significant limitations which complicate their
rapid introduction into medicine.
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27
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Chang KJ, Wu HY, Yarmishyn AA, Li CY, Hsiao YJ, Chi YC, Lo TC, Dai HJ, Yang YC, Liu DH, Hwang DK, Chen SJ, Hsu CC, Kao CL. Genetics behind Cerebral Disease with Ocular Comorbidity: Finding Parallels between the Brain and Eye Molecular Pathology. Int J Mol Sci 2022; 23:ijms23179707. [PMID: 36077104 PMCID: PMC9456058 DOI: 10.3390/ijms23179707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/18/2022] [Accepted: 08/22/2022] [Indexed: 11/30/2022] Open
Abstract
Cerebral visual impairments (CVIs) is an umbrella term that categorizes miscellaneous visual defects with parallel genetic brain disorders. While the manifestations of CVIs are diverse and ambiguous, molecular diagnostics stand out as a powerful approach for understanding pathomechanisms in CVIs. Nevertheless, the characterization of CVI disease cohorts has been fragmented and lacks integration. By revisiting the genome-wide and phenome-wide association studies (GWAS and PheWAS), we clustered a handful of renowned CVIs into five ontology groups, namely ciliopathies (Joubert syndrome, Bardet–Biedl syndrome, Alstrom syndrome), demyelination diseases (multiple sclerosis, Alexander disease, Pelizaeus–Merzbacher disease), transcriptional deregulation diseases (Mowat–Wilson disease, Pitt–Hopkins disease, Rett syndrome, Cockayne syndrome, X-linked alpha-thalassaemia mental retardation), compromised peroxisome disorders (Zellweger spectrum disorder, Refsum disease), and channelopathies (neuromyelitis optica spectrum disorder), and reviewed several mutation hotspots currently found to be associated with the CVIs. Moreover, we discussed the common manifestations in the brain and the eye, and collated animal study findings to discuss plausible gene editing strategies for future CVI correction.
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Affiliation(s)
- Kao-Jung Chang
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
| | - Hsin-Yu Wu
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | | | - Cheng-Yi Li
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Yu-Jer Hsiao
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Yi-Chun Chi
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Tzu-Chen Lo
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - He-Jhen Dai
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Yi-Chiang Yang
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Ding-Hao Liu
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - De-Kuang Hwang
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Shih-Jen Chen
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Chih-Chien Hsu
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (C.-C.H.); (C.-L.K.); Tel.: +886-2-287-573-25 (C.-C.H.); +886-2-287-573-63 (C.-L.K.)
| | - Chung-Lan Kao
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Department of Physical Medicine and Rehabilitation, School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Center for Intelligent Drug Systems and Smart Bio-Devices (IDS2B), National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
- Correspondence: (C.-C.H.); (C.-L.K.); Tel.: +886-2-287-573-25 (C.-C.H.); +886-2-287-573-63 (C.-L.K.)
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28
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Newsome SD, Johnson T. Stiff person syndrome spectrum disorders; more than meets the eye. J Neuroimmunol 2022; 369:577915. [PMID: 35717735 PMCID: PMC9274902 DOI: 10.1016/j.jneuroim.2022.577915] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 05/21/2022] [Accepted: 06/07/2022] [Indexed: 10/18/2022]
Abstract
Stiff person syndrome spectrum disorders (SPSD) are a group of rare neuroimmunological disorders that often include painful spasms and rigidity. However, patients have highly heterogeneous signs and symptoms which may reflect different mechanistic disease processes. Understanding subsets of patients based on clinical phenotype may be important for prognosis and guiding treatment. The goal of this review is to provide updates on SPSD and its expanding clinical spectrum, prognostic markers, and treatment considerations. Further, we describe the current understanding in immunopathogenesis and highlight gaps in our knowledge appropriate for future research directions. Examples of revised diagnostic criteria for SPSD based on phenotype are also presented.
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Affiliation(s)
- Scott D Newsome
- Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Tory Johnson
- Johns Hopkins University School of Medicine, Baltimore, MD, USA; Section of Infections of the Nervous System, NINDS, NIH, Bethesda, MD, USA
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29
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Gentiletti D, de Curtis M, Gnatkovsky V, Suffczynski P. Focal seizures are organized by feedback between neural activity and ion concentration changes. eLife 2022; 11:68541. [PMID: 35916367 PMCID: PMC9377802 DOI: 10.7554/elife.68541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/12/2022] [Indexed: 11/13/2022] Open
Abstract
Human and animal EEG data demonstrate that focal seizures start with low-voltage fast activity, evolve into rhythmic burst discharges and are followed by a period of suppressed background activity. This suggests that processes with dynamics in the range of tens of seconds govern focal seizure evolution. We investigate the processes associated with seizure dynamics by complementing the Hodgkin-Huxley mathematical model with the physical laws that dictate ion movement and maintain ionic gradients. Our biophysically realistic computational model closely replicates the electrographic pattern of a typical human focal seizure characterized by low voltage fast activity onset, tonic phase, clonic phase and postictal suppression. Our study demonstrates, for the first time in silico, the potential mechanism of seizure initiation by inhibitory interneurons via the initial build-up of extracellular K+ due to intense interneuronal spiking. The model also identifies ionic mechanisms that may underlie a key feature in seizure dynamics, i.e., progressive slowing down of ictal discharges towards the end of seizure. Our model prediction of specific scaling of inter-burst intervals is confirmed by seizure data recorded in the whole guinea pig brain in vitro and in humans, suggesting that the observed termination pattern may hold across different species. Our results emphasize ionic dynamics as elementary processes behind seizure generation and indicate targets for new therapeutic strategies.
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30
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Kovács Z, Skatchkov SN, Szabó Z, Qahtan S, Méndez-González MP, Malpica-Nieves CJ, Eaton MJ, Kardos J, Héja L. Putrescine Intensifies Glu/GABA Exchange Mechanism and Promotes Early Termination of Seizures. Int J Mol Sci 2022; 23:ijms23158191. [PMID: 35897767 PMCID: PMC9331600 DOI: 10.3390/ijms23158191] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/30/2022] [Accepted: 07/21/2022] [Indexed: 02/01/2023] Open
Abstract
Endogenous anticonvulsant mechanisms represent a reliable and currently underdeveloped strategy against recurrent seizures and may recall novel original therapeutics. Here, we investigated whether the intensification of the astroglial Glu-GABA exchange mechanism by application of the GABA precursor putrescine (PUT) may be effective against convulsive and non-convulsive seizures. We explored the potential of PUT to inhibit spontaneous spike-and-wave discharges (SWDs) in WAG/Rij rats, a genetic model of absence epilepsy. Significant shortening of SWDs in response to intraperitoneally applied PUT has been observed, which could be antagonized by blocking GAT-2/3-mediated astrocytic GABA release with the specific inhibitor SNAP-5114. Direct application of exogenous GABA also reduced SWD duration, suggesting that PUT-triggered astroglial GABA release through GAT-2/3 may be a critical step in limiting seizure duration. PUT application also dose-dependently shortened seizure-like events (SLEs) in the low-[Mg2+] in vitro model of temporal lobe epilepsy. SNAP-5114 reversed the antiepileptic effect of PUT in the in vitro model as well, further confirming that PUT reduces seizure duration by triggering glial GABA release. In accordance, we observed that PUT specifically reduces the frequency of excitatory synaptic potentials, suggesting that it specifically acts at excitatory synapses. We also identified that PUT specifically eliminated the tonic depolarization-induced desynchronization of SLEs. Since PUT is an important source of glial GABA and we previously showed significant GABA release, it is suggested that the astroglial Glu-GABA exchange mechanism plays a key role in limiting ictal discharges, potentially opening up novel pathways to control seizure propagation and generalization.
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Affiliation(s)
- Zsolt Kovács
- Department of Biology, Savaria University Centre, ELTE Eötvös Loránd University, Károlyi Gáspár tér 4, 9700 Szombathely, Hungary;
| | - Serguei N. Skatchkov
- Department of Physiology, Universidad Central del Caribe, Bayamon, PR 00960, USA; (S.N.S.); (C.J.M.-N.)
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, PR 00960, USA; (M.P.M.-G.); (M.J.E.)
| | - Zsolt Szabó
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117 Budapest, Hungary; (Z.S.); (S.Q.); (J.K.)
| | - Saif Qahtan
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117 Budapest, Hungary; (Z.S.); (S.Q.); (J.K.)
- Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
- College of Science, University of Al-Qadisiyah, Al-Diwaniyah 58001, Iraq
| | - Miguel P. Méndez-González
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, PR 00960, USA; (M.P.M.-G.); (M.J.E.)
- Natural Sciences Department, University of Puerto Rico in Aguadilla, Aguadilla, PR 00604, USA
- Department of Science and Technology, Antilles Adventist University, Mayagüez, PR 00681, USA
| | - Christian J. Malpica-Nieves
- Department of Physiology, Universidad Central del Caribe, Bayamon, PR 00960, USA; (S.N.S.); (C.J.M.-N.)
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, PR 00960, USA; (M.P.M.-G.); (M.J.E.)
| | - Misty J. Eaton
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, PR 00960, USA; (M.P.M.-G.); (M.J.E.)
| | - Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117 Budapest, Hungary; (Z.S.); (S.Q.); (J.K.)
| | - László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117 Budapest, Hungary; (Z.S.); (S.Q.); (J.K.)
- Correspondence:
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Lignani G. Unblock the Block! Preventing Inhibitory Failure to Maintain Inhibitory Restraint. Epilepsy Curr 2022; 22:244-245. [PMID: 36187146 PMCID: PMC9483764 DOI: 10.1177/15357597221098808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Mueller JS, Tescarollo FC, Sun H. DREADDs in Epilepsy Research: Network-Based Review. Front Mol Neurosci 2022; 15:863003. [PMID: 35465094 PMCID: PMC9021489 DOI: 10.3389/fnmol.2022.863003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 03/17/2022] [Indexed: 12/12/2022] Open
Abstract
Epilepsy can be interpreted as altered brain rhythms from overexcitation or insufficient inhibition. Chemogenetic tools have revolutionized neuroscience research because they allow “on demand” excitation or inhibition of neurons with high cellular specificity. Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) are the most frequently used chemogenetic techniques in epilepsy research. These engineered muscarinic receptors allow researchers to excite or inhibit targeted neurons with exogenous ligands. As a result, DREADDs have been applied to investigate the underlying cellular and network mechanisms of epilepsy. Here, we review the existing literature that has applied DREADDs to understand the pathophysiology of epilepsy. The aim of this review is to provide a general introduction to DREADDs with a focus on summarizing the current main findings in experimental epilepsy research using these techniques. Furthermore, we explore how DREADDs may be applied therapeutically as highly innovative treatments for epilepsy.
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Silkis IG. Hypothetical Mechanism of Resting Tremor in Parkinson’s Disease. NEUROCHEM J+ 2022. [DOI: 10.1134/s1819712422010111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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Godoy LD, Prizon T, Rossignoli MT, Leite JP, Liberato JL. Parvalbumin Role in Epilepsy and Psychiatric Comorbidities: From Mechanism to Intervention. Front Integr Neurosci 2022; 16:765324. [PMID: 35250498 PMCID: PMC8891758 DOI: 10.3389/fnint.2022.765324] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 01/24/2022] [Indexed: 12/22/2022] Open
Abstract
Parvalbumin is a calcium-binding protein present in inhibitory interneurons that play an essential role in regulating many physiological processes, such as intracellular signaling and synaptic transmission. Changes in parvalbumin expression are deeply related to epilepsy, which is considered one of the most disabling neuropathologies. Epilepsy is a complex multi-factor group of disorders characterized by periods of hypersynchronous activity and hyperexcitability within brain networks. In this scenario, inhibitory neurotransmission dysfunction in modulating excitatory transmission related to the loss of subsets of parvalbumin-expressing inhibitory interneuron may have a prominent role in disrupted excitability. Some studies also reported that parvalbumin-positive interneurons altered function might contribute to psychiatric comorbidities associated with epilepsy, such as depression, anxiety, and psychosis. Understanding the epileptogenic process and comorbidities associated with epilepsy have significantly advanced through preclinical and clinical investigation. In this review, evidence from parvalbumin altered function in epilepsy and associated psychiatric comorbidities were explored with a translational perspective. Some advances in potential therapeutic interventions are highlighted, from current antiepileptic and neuroprotective drugs to cutting edge modulation of parvalbumin subpopulations using optogenetics, designer receptors exclusively activated by designer drugs (DREADD) techniques, transcranial magnetic stimulation, genome engineering, and cell grafting. Creating new perspectives on mechanisms and therapeutic strategies is valuable for understanding the pathophysiology of epilepsy and its psychiatric comorbidities and improving efficiency in clinical intervention.
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Affiliation(s)
- Lívea Dornela Godoy
- Department of Psychology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Tamiris Prizon
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Matheus Teixeira Rossignoli
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - João Pereira Leite
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
- João Pereira Leite,
| | - José Luiz Liberato
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
- *Correspondence: José Luiz Liberato,
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Kadam SD. Symphony Conductors Lose the Baton: Role of Fast-Spiking Interneurons in Orchestrating DS. Epilepsy Curr 2021; 21:192-193. [PMID: 34867101 PMCID: PMC8609584 DOI: 10.1177/15357597211003550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Impaired Theta-Gamma Coupling Indicates Inhibitory Dysfunction and Seizure Risk in a Dravet Syndrome Mouse Model Jansen NA, Perez C, Schenke M, et al. J Neurosci. 2021;41(3):524-537. doi:org/10.1523/JNEUROSCI.2132-20.2020 Dravet syndrome (DS) is an epileptic encephalopathy that still lacks biomarkers for epileptogenesis and its treatment. Dysfunction of NaV1.1 sodium channels, which are chiefly expressed in inhibitory interneurons, explains the epileptic phenotype. Understanding the network effects of these cellular deficits may help predict epileptogenesis. Here, we studied theta–gamma coupling as a potential marker for altered inhibitory functioning and epileptogenesis in a DS mouse model. We found that cortical theta–gamma coupling was reduced in both male and female juvenile DS mice and persisted only if spontaneous seizures occurred. Theta–gamma coupling was partly restored by cannabidiol. Locally disrupting NaV1.1 expression in the hippocampus or cortex yielded early attenuation of theta–gamma coupling, which in the hippocampus associated with fast ripples, and which was replicated in a computational model when voltage-gated sodium currents were impaired in basket cells. Our results indicate attenuated theta–gamma coupling as a promising early indicator of inhibitory dysfunction and seizure risk in DS.
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Human stem cell-derived GABAergic neurons functionally integrate into human neuronal networks. Sci Rep 2021; 11:22050. [PMID: 34764308 PMCID: PMC8585944 DOI: 10.1038/s41598-021-01270-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/26/2021] [Indexed: 02/03/2023] Open
Abstract
Gamma-aminobutyric acid (GABA)-releasing interneurons modulate neuronal network activity in the brain by inhibiting other neurons. The alteration or absence of these cells disrupts the balance between excitatory and inhibitory processes, leading to neurological disorders such as epilepsy. In this regard, cell-based therapy may be an alternative therapeutic approach. We generated light-sensitive human embryonic stem cell (hESC)-derived GABAergic interneurons (hdIN) and tested their functionality. After 35 days in vitro (DIV), hdINs showed electrophysiological properties and spontaneous synaptic currents comparable to mature neurons. In co-culture with human cortical neurons and after transplantation (AT) into human brain tissue resected from patients with drug-resistant epilepsy, light-activated channelrhodopsin-2 (ChR2) expressing hdINs induced postsynaptic currents in human neurons, strongly suggesting functional efferent synapse formation. These results provide a proof-of-concept that hESC-derived neurons can integrate and modulate the activity of a human host neuronal network. Therefore, this study supports the possibility of precise temporal control of network excitability by transplantation of light-sensitive interneurons.
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Cheah CS, Beckman MA, Catterall WA, Oakley JC. Sharp-Wave Ripple Frequency and Interictal Epileptic Discharges Increase in Tandem During Thermal Induction of Seizures in a Mouse Model of Genetic Epilepsy. Front Cell Neurosci 2021; 15:751762. [PMID: 34733140 PMCID: PMC8558377 DOI: 10.3389/fncel.2021.751762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Dravet Syndrome (DS) is a genetic, infantile-onset epilepsy with refractory seizures and severe cognitive impairment. While network level pathophysiology is poorly understood, work in genetic mouse models of DS reveals selective reduction of inhibitory interneuron excitability, a likely mechanism of seizures and comorbidities. Consistent with the critical role of interneurons in timing and recruitment of network activity, hippocampal sharp wave ripples (SPW-R)—interneuron dependent compound brain rhythms essential for spatial learning and memory—are less frequent and ripple frequency is slower in DS mice, both likely to impair cognitive performance. Febrile seizures are characteristic of DS, reflecting a temperature-dependent shift in excitation–inhibition balance. DS interneurons are sensitive to depolarization block and may fall silent with increased excitation precipitating epileptic transformation of ripples. To determine the temperature dependence of SWP-R features and relationship of SPW-R to hippocampal interictal activity, we recorded hippocampal local field potentials in a DS mouse model and wildtype littermate controls while increasing core body temperature. In both genotypes, temperature elevation speeds ripple frequency, although DS ripples remain consistently slower. The rate of SPW-R also increases in both genotypes but subsequently falls in DS mice as interictal epileptic activity simultaneously increases preceding a thermally-evoked seizure. Epileptic events occur intermixed with SPW-R, some during SPW-R burst complexes, and transiently suppress SPW-R occurrence suggesting shared network elements. Together these data demonstrate a temperature dependence of SPW-R rate and ripple frequency and suggest a pathophysiologic mechanism by which elevated temperature transforms a normal brain rhythm into epileptic event.
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Affiliation(s)
- Christine S Cheah
- Department of Neurology, University of Washington, Seattle, WA, United States
| | - Megan A Beckman
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - William A Catterall
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - John C Oakley
- Department of Neurology, University of Washington, Seattle, WA, United States.,Department of Pharmacology, University of Washington, Seattle, WA, United States
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Jablonski J, Hoffmann L, Blümcke I, Fejtová A, Uebe S, Ekici AB, Gnatkovsky V, Kobow K. Experimental Epileptogenesis in a Cell Culture Model of Primary Neurons from Rat Brain: A Temporal Multi-Scale Study. Cells 2021; 10:cells10113004. [PMID: 34831225 PMCID: PMC8616120 DOI: 10.3390/cells10113004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/27/2021] [Accepted: 11/02/2021] [Indexed: 12/24/2022] Open
Abstract
Understanding seizure development requires an integrated knowledge of different scales of organization of epileptic networks. We developed a model of “epilepsy-in-a-dish” based on dissociated primary neuronal cells from neonatal rat hippocampus. We demonstrate how a single application of glutamate stimulated neurons to generate spontaneous synchronous spiking activity with further progression into spontaneous seizure-like events after a distinct latency period. By computational analysis, we compared the observed neuronal activity in vitro with intracranial electroencephalography (EEG) data recorded from epilepsy patients and identified strong similarities, including a related sequence of events with defined onset, progression, and termination. Next, a link between the neurophysiological changes with network composition and cellular structure down to molecular changes was established. Temporal development of epileptiform network activity correlated with increased neurite outgrowth and altered branching, increased ratio of glutamatergic over GABAergic synapses, and loss of calbindin-positive interneurons, as well as genome-wide alterations in DNA methylation. Differentially methylated genes were engaged in various cellular activities related to cellular structure, intracellular signaling, and regulation of gene expression. Our data provide evidence that a single short-term excess of glutamate is sufficient to induce a cascade of events covering different scales from molecule- to network-level, all of which jointly contribute to seizure development.
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Affiliation(s)
- Janos Jablonski
- Department of Neuropathology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.J.); (L.H.); (I.B.)
| | - Lucas Hoffmann
- Department of Neuropathology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.J.); (L.H.); (I.B.)
| | - Ingmar Blümcke
- Department of Neuropathology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.J.); (L.H.); (I.B.)
| | - Anna Fejtová
- Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany;
| | - Steffen Uebe
- NGS Core Unit, Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (S.U.); (A.B.E.)
| | - Arif B. Ekici
- NGS Core Unit, Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (S.U.); (A.B.E.)
| | - Vadym Gnatkovsky
- Department of Epileptology, University Hospital Bonn, 53127 Bonn, Germany;
| | - Katja Kobow
- Department of Neuropathology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.J.); (L.H.); (I.B.)
- Correspondence: ; Tel.: +49-9131-8522859
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Dudok B, Klein PM, Soltesz I. Toward Understanding the Diverse Roles of Perisomatic Interneurons in Epilepsy. Epilepsy Curr 2021; 22:54-60. [PMID: 35233202 PMCID: PMC8832350 DOI: 10.1177/15357597211053687] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Epileptic seizures are associated with excessive neuronal spiking. Perisomatic
γ-aminobutyric acid (GABA)ergic interneurons specifically innervate the subcellular
domains of postsynaptic excitatory cells that are critical for spike generation. With a
revolution in transcriptomics-based cell taxonomy driving the development of novel
transgenic mouse lines, selectively monitoring and modulating previously elusive
interneuron types is becoming increasingly feasible. Emerging evidence suggests that the
three types of hippocampal perisomatic interneurons, axo-axonic cells, along with
parvalbumin- and cholecystokinin-expressing basket cells, each follow unique activity
patterns in vivo, suggesting distinctive roles in regulating epileptic networks.
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Affiliation(s)
- Barna Dudok
- Department of Neurosurgery, Stanford University, Stanford, CA, USA
| | - Peter M. Klein
- Department of Neurosurgery, Stanford University, Stanford, CA, USA
| | - Ivan Soltesz
- Department of Neurosurgery, Stanford University, Stanford, CA, USA
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40
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Tok S, Ahnaou A, Drinkenburg W. Functional Neurophysiological Biomarkers of Early-Stage Alzheimer's Disease: A Perspective of Network Hyperexcitability in Disease Progression. J Alzheimers Dis 2021; 88:809-836. [PMID: 34420957 PMCID: PMC9484128 DOI: 10.3233/jad-210397] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Network hyperexcitability (NH) has recently been suggested as a potential neurophysiological indicator of Alzheimer’s disease (AD), as new, more accurate biomarkers of AD are sought. NH has generated interest as a potential indicator of certain stages in the disease trajectory and even as a disease mechanism by which network dysfunction could be modulated. NH has been demonstrated in several animal models of AD pathology and multiple lines of evidence point to the existence of NH in patients with AD, strongly supporting the physiological and clinical relevance of this readout. Several hypotheses have been put forward to explain the prevalence of NH in animal models through neurophysiological, biochemical, and imaging techniques. However, some of these hypotheses have been built on animal models with limitations and caveats that may have derived NH through other mechanisms or mechanisms without translational validity to sporadic AD patients, potentially leading to an erroneous conclusion of the underlying cause of NH occurring in patients with AD. In this review, we discuss the substantiation for NH in animal models of AD pathology and in human patients, as well as some of the hypotheses considering recently developed animal models that challenge existing hypotheses and mechanisms of NH. In addition, we provide a preclinical perspective on how the development of animal models incorporating AD-specific NH could provide physiologically relevant translational experimental data that may potentially aid the discovery and development of novel therapies for AD.
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Affiliation(s)
- Sean Tok
- Department of Neuroscience, Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium.,Groningen Institute for Evolutionary Life Sciences, Faculty of Science and Engineering, University of Groningen, The Netherlands
| | - Abdallah Ahnaou
- Department of Neuroscience, Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Wilhelmus Drinkenburg
- Department of Neuroscience, Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium.,Groningen Institute for Evolutionary Life Sciences, Faculty of Science and Engineering, University of Groningen, The Netherlands
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Salvati KA, Mason AJ, Gailey CD, Wang EJ, Fu Z, Beenhakker MP. Mice Harboring a Non-Functional CILK1/ICK Allele Fail to Model the Epileptic Phenotype in Patients Carrying Variant CILK1/ICK. Int J Mol Sci 2021; 22:ijms22168875. [PMID: 34445580 PMCID: PMC8396347 DOI: 10.3390/ijms22168875] [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: 08/01/2021] [Revised: 08/15/2021] [Accepted: 08/15/2021] [Indexed: 11/16/2022] Open
Abstract
CILK1 (ciliogenesis associated kinase 1)/ICK (intestinal cell kinase) is a highly conserved protein kinase that regulates primary cilia structure and function. CILK1 mutations cause a wide spectrum of human diseases collectively called ciliopathies. While several CILK1 heterozygous variants have been recently linked to juvenile myoclonic epilepsy (JME), it remains unclear whether these mutations cause seizures. Herein, we investigated whether mice harboring either a heterozygous null Cilk1 (Cilk1+/−) mutation or a heterozygous loss-of-function Cilk1 mutation (Cilk1R272Q/+) have epilepsy. We first evaluated the spontaneous seizure phenotype of Cilk1+/− and Cilk1R272Q/+ mice relative to wildtype littermates. We observed no electrographic differences among the three mouse genotypes during prolonged recordings. We also evaluated electrographic and behavioral responses of mice recovering from isoflurane anesthesia, an approach recently used to measure seizure-like activity. Again, we observed no electrographic or behavioral differences in control versus Cilk1+/− and Cilk1R272Q/+ mice upon isoflurane recovery. These results indicate that mice bearing a non-functional copy of Cilk1 fail to produce electrographic patterns resembling those of JME patients with a variant CILK1 copy. Our findings argue against CILK1 haploinsufficiency being the mechanism that links CILK1 variants to JME.
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Affiliation(s)
- Kathryn A. Salvati
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA; (K.A.S.); (A.J.M.); (C.D.G.); (E.J.W.)
- Department of Neurological Surgery and Weill Institute for Neuroscience, University of California, San Francisco, CA 94143, USA
| | - Ashley J. Mason
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA; (K.A.S.); (A.J.M.); (C.D.G.); (E.J.W.)
| | - Casey D. Gailey
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA; (K.A.S.); (A.J.M.); (C.D.G.); (E.J.W.)
| | - Eric J. Wang
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA; (K.A.S.); (A.J.M.); (C.D.G.); (E.J.W.)
| | - Zheng Fu
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA; (K.A.S.); (A.J.M.); (C.D.G.); (E.J.W.)
- UVA Cancer Center, Cancer Biology Program, University of Virginia, Charlottesville, VA 22908, USA
- Correspondence: (Z.F.); (M.P.B.)
| | - Mark P. Beenhakker
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA; (K.A.S.); (A.J.M.); (C.D.G.); (E.J.W.)
- UVA Brain Institute, University of Virginia, Charlottesville, VA 22908, USA
- Correspondence: (Z.F.); (M.P.B.)
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Smit DJA, Andreassen OA, Boomsma DI, Burwell SJ, Chorlian DB, de Geus EJC, Elvsåshagen T, Gordon RL, Harper J, Hegerl U, Hensch T, Iacono WG, Jawinski P, Jönsson EG, Luykx JJ, Magne CL, Malone SM, Medland SE, Meyers JL, Moberget T, Porjesz B, Sander C, Sisodiya SM, Thompson PM, van Beijsterveldt CEM, van Dellen E, Via M, Wright MJ. Large-scale collaboration in ENIGMA-EEG: A perspective on the meta-analytic approach to link neurological and psychiatric liability genes to electrophysiological brain activity. Brain Behav 2021; 11:e02188. [PMID: 34291596 PMCID: PMC8413828 DOI: 10.1002/brb3.2188] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 03/12/2021] [Accepted: 04/30/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE The ENIGMA-EEG working group was established to enable large-scale international collaborations among cohorts that investigate the genetics of brain function measured with electroencephalography (EEG). In this perspective, we will discuss why analyzing the genetics of functional brain activity may be crucial for understanding how neurological and psychiatric liability genes affect the brain. METHODS We summarize how we have performed our currently largest genome-wide association study of oscillatory brain activity in EEG recordings by meta-analyzing the results across five participating cohorts, resulting in the first genome-wide significant hits for oscillatory brain function located in/near genes that were previously associated with psychiatric disorders. We describe how we have tackled methodological issues surrounding genetic meta-analysis of EEG features. We discuss the importance of harmonizing EEG signal processing, cleaning, and feature extraction. Finally, we explain our selection of EEG features currently being investigated, including the temporal dynamics of oscillations and the connectivity network based on synchronization of oscillations. RESULTS We present data that show how to perform systematic quality control and evaluate how choices in reference electrode and montage affect individual differences in EEG parameters. CONCLUSION The long list of potential challenges to our large-scale meta-analytic approach requires extensive effort and organization between participating cohorts; however, our perspective shows that these challenges are surmountable. Our perspective argues that elucidating the genetic of EEG oscillatory activity is a worthwhile effort in order to elucidate the pathway from gene to disease liability.
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Affiliation(s)
- Dirk J A Smit
- Department of Psychiatry, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Ole A Andreassen
- Norwegian Centre for Mental Disorders Research (NORMENT), Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Dorret I Boomsma
- Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Scott J Burwell
- Department of Psychology, Minnesota Center for Twin and Family Research, University of Minnesota, Minneapolis, MN, USA.,Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA
| | - David B Chorlian
- Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry, Downstate Health Sciences University, Brooklyn, NY, USA
| | - Eco J C de Geus
- Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Torbjørn Elvsåshagen
- Norwegian Centre for Mental Disorders Research (NORMENT), Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,Department of Neurology, Oslo University Hospital, Oslo, Norway
| | - Reyna L Gordon
- Department of Otolaryngology, Vanderbilt University Medical Center, Nashville, TN, USA.,Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA.,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
| | - Jeremy Harper
- Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA
| | - Ulrich Hegerl
- Department of Psychiatry, Psychosomatics, and Psychotherapy, Goethe Universität Frankfurt am Main, Frankfurt, Germany
| | - Tilman Hensch
- Department of Psychiatry and Psychotherapy, University of Leipzig Medical Center, Leipzig, Germany.,LIFE - Leipzig Research Center for Civilization Diseases, Universität Leipzig, Leipzig, Germany.,IU International University, Erfurt, Germany
| | - William G Iacono
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - Philippe Jawinski
- LIFE - Leipzig Research Center for Civilization Diseases, Universität Leipzig, Leipzig, Germany.,Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Erik G Jönsson
- TOP-Norment, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet & Stockholm Health Care Services, Stockholm Region, Stockholm, Sweden
| | - Jurjen J Luykx
- Department of Psychiatry, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.,Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.,Outpatient Second Opinion Clinic, GGNet Mental Health, Apeldoorn, The Netherlands
| | - Cyrille L Magne
- Psychology Department, Middle Tennessee State University, Murfreesboro, TN, USA.,Literacy Studies Ph.D. Program, Middle Tennessee State University, Mufreesboro, TN, USA
| | - Stephen M Malone
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - Sarah E Medland
- QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Jacquelyn L Meyers
- Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry, Downstate Health Sciences University, Brooklyn, NY, USA.,Department of Psychiatry, State University of New York Downstate Health Sciences University, Brooklyn, NY, USA
| | - Torgeir Moberget
- Department of Psychiatry, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Department of Psychology, Faculty of Social Sciences, University of Oslo, Oslo, Norway
| | - Bernice Porjesz
- Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry, Downstate Health Sciences University, Brooklyn, NY, USA
| | - Christian Sander
- Department of Psychiatry and Psychotherapy, University of Leipzig Medical Center, Leipzig, Germany
| | - Sanjay M Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK.,Chalfont Centre for Epilepsy, Chalfont-St-Peter, UK
| | - Paul M Thompson
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Marina del Rey, CA, USA
| | | | - Edwin van Dellen
- Department of Psychiatry, Department of Intensive Care Medicine, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Marc Via
- Brainlab-Cognitive Neuroscience Research Group, Department of Clinical Psychology and Psychobiology, and Institute of Neurosciences (UBNeuro), Universitat de Barcelona, Barcelona, Spain.,Institut de Recerca Sant Joan de Déu (IRSJD), Esplugues de Llobregat, Spain
| | - Margaret J Wright
- Queensland Brain Institute, University of Queensland, Brisbane, QLD, Australia.,Centre for Advanced Imaging, University of Queensland, Brisbane, QLD, Australia
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43
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Schilling S, Chausse B, Dikmen HO, Almouhanna F, Hollnagel JO, Lewen A, Kann O. TLR2- and TLR3-activated microglia induce different levels of neuronal network dysfunction in a context-dependent manner. Brain Behav Immun 2021; 96:80-91. [PMID: 34015428 DOI: 10.1016/j.bbi.2021.05.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 05/11/2021] [Accepted: 05/15/2021] [Indexed: 02/06/2023] Open
Abstract
Recognition of pathogen- or damage-associated molecular patterns (PAMPs, DAMPs) by innate Toll-like receptors (TLRs) is central to the activation of microglia (brain macrophages) in many CNS diseases. Notably, TLR-mediated microglial activation is complex and modulated by additional exogenous and endogenous immunological signals. The impact of different microglial reactive phenotypes on electrical activity and neurotransmission is widely unknown, however. We explored the effects of TLR ligands on microglia and neuronal network function in rat organotypic hippocampal slice cultures (in situ), i.e., postnatal cortical tissue lacking adaptive immunity. Single exposure of slice cultures to TLR2 or TLR3 ligands [PGN, poly(I:C)] for 2-3 days induced moderate microglial activation featuring IL-6 and TNF-α release and only mild alterations of fast neuronal gamma band oscillations (30-70 Hz) that are fundamental to higher cognitive functions, such as perception, memory and behavior. Paired exposure to TLR3/TLR2 or TLR3/TLR4 ligands (LPS) induced nitric oxide (NO) release, enhanced TNF-α release, and associated with advanced network dysfunction, including slowing to the beta frequency band (12-30 Hz) and neural bursts (hyperexcitability). Paired exposure to a TLR ligand and the leukocyte cytokine IFN-γ enhanced NO release and associated with severe network dysfunction, albeit sensitive parvalbumin- and somatostatin-positive inhibitory interneurons were preserved. Notably, the neuronal disturbance was prevented by either microglial depletion or pharmacological inhibition of oxidant-producing enzymes, inducible NO synthase (iNOS) and NADPH oxidase. In conclusion, TLR-activated microglia can induce different levels of neuronal network dysfunction, in which severe dysfunction is mainly caused by reactive oxygen and nitrogen species rather than proinflammatory cytokines. Our findings provide a mechanistic insight into microglial activation and functional neuronal network impairment, with relevance to neuroinflammation and neurodegeneration observed in, e.g., meningoencephalitis, multiple sclerosis and Alzheimer's disease.
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Affiliation(s)
- Simone Schilling
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Bruno Chausse
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Hasan Onur Dikmen
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Fadi Almouhanna
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Jan-Oliver Hollnagel
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Andrea Lewen
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, D-69120 Heidelberg, Germany.
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44
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Wang X, Zhang Y, Cheng W, Gao Y, Li S. Decreased excitatory drive onto hilar neuronal nitric oxide synthase expressing interneurons in chronic models of epilepsy. Brain Res 2021; 1764:147467. [PMID: 33831408 DOI: 10.1016/j.brainres.2021.147467] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 11/29/2022]
Abstract
Excitation-inhibition imbalance of GABAergic interneurons is predisposed to develop chronic temporal lobe epilepsy (TLE). We have previously shown that virtually every neuronal nitric oxide synthase (nNOS)-positive cell is a GABAergic inhibitory interneuron in the denate gyrus. The present study was designed to quantify the number of nNOS-containing hilar interneurons using stereology in pilocapine- and kainic acid (KA)-exposed transgenic adult mice that expressed GFP under the nNOS promoter. In addition, we studied the properties of miniature excitatory postsynaptic current (mEPSC) and paired-pulse response ratio (PPR) of evoked EPSC in nNOS interneurons using whole cell recording techniques. Results showed that there were fewer nNOS-immunoreactive interneurons of chronically epileptic animals. Importantly, patch-clamp recordings revealed reduction in mEPSC frequency, indicating diminished global excitatory input. In contrast, PPR of evoked EPSC following the granule cell layer stimulation was increased in epileptic animals suggesting reduced neurotransmitter release from granule cell input. In summary, we propose that impaired excitatory drive onto hippocampal nNOS interneurons may be implicated in the development of refractory epilepsy.
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Affiliation(s)
- Xiaona Wang
- Henan Neurodevelopment Engineering Research Center for Children, Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, 33 Longhu Outer Circle Dong Road, Zhengzhou, 450018, Henan, China.
| | - Yaodong Zhang
- Henan Neurodevelopment Engineering Research Center for Children, Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, 33 Longhu Outer Circle Dong Road, Zhengzhou, 450018, Henan, China
| | - Weyland Cheng
- Department of Orthopaedics, Children's Hospital Affiliated to Zhengzhou University, 33 Longhu Outer Circle Dong Road, Zhengzhou 450018, Henan, China
| | - Yinbo Gao
- Henan Neurodevelopment Engineering Research Center for Children, Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, 33 Longhu Outer Circle Dong Road, Zhengzhou, 450018, Henan, China
| | - Shao Li
- Department of Physiology, Liaoning Provincial Key Laboratory of Cerebral Diseases, National-Local Joint Engineering Research Center for Drug-Research and Development (R&D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, Liaoning 116044, China
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45
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An inventory of basic research in temporal lobe epilepsy. Rev Neurol (Paris) 2021; 177:1069-1081. [PMID: 34176659 DOI: 10.1016/j.neurol.2021.02.390] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/26/2021] [Accepted: 02/05/2021] [Indexed: 12/25/2022]
Abstract
Temporal lobe epilepsy is a severe neurological disease, characterized by seizure occurrence and invalidating cognitive co-morbidities, which affects up to 1% of the adults. Roughly one third of the patients are resistant to any conventional pharmacological treatments. The last option in that case is the surgical removal of the epileptic focus, with no guarantee for clinical symptom alleviation. This state of affairs requests the identification of cellular or molecular targets for novel therapeutic approaches with limited side effects. Here we review some generalities about the disease as well as some of the most recent discoveries about the cellular and molecular mechanisms of TLE, and the latest perspectives for novel treatments.
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46
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Cui Y, Zhang S, Liang Y, Wang X, Ferraro TN, Chen Y. Consensus clustering of single-cell RNA-seq data by enhancing network affinity. Brief Bioinform 2021; 22:6308199. [PMID: 34160582 PMCID: PMC8574980 DOI: 10.1093/bib/bbab236] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 05/29/2021] [Accepted: 06/01/2021] [Indexed: 12/18/2022] Open
Abstract
Elucidation of cell subpopulations at high resolution is a key and challenging goal of single-cell ribonucleic acid (RNA) sequencing (scRNA-seq) data analysis. Although unsupervised clustering methods have been proposed for de novo identification of cell populations, their performance and robustness suffer from the high variability, low capture efficiency and high dropout rates which are characteristic of scRNA-seq experiments. Here, we present a novel unsupervised method for Single-cell Clustering by Enhancing Network Affinity (SCENA), which mainly employed three strategies: selecting multiple gene sets, enhancing local affinity among cells and clustering of consensus matrices. Large-scale validations on 13 real scRNA-seq datasets show that SCENA has high accuracy in detecting cell populations and is robust against dropout noise. When we applied SCENA to large-scale scRNA-seq data of mouse brain cells, known cell types were successfully detected, and novel cell types of interneurons were identified with differential expression of gamma-aminobutyric acid receptor subunits and transporters. SCENA is equipped with CPU + GPU (Central Processing Units + Graphics Processing Units) heterogeneous parallel computing to achieve high running speed. The high performance and running speed of SCENA combine into a new and efficient platform for biological discoveries in clustering analysis of large and diverse scRNA-seq datasets.
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Affiliation(s)
- Yaxuan Cui
- College of Computer and Information Engineering, Tianjin Normal University, China
| | - Shaoqiang Zhang
- College of Computer and Information Engineering, Tianjin Normal University, China
| | - Ying Liang
- College of Computer and Information Engineering, Tianjin Normal University, China
| | - Xiangyun Wang
- College of Computer and Information Engineering, Tianjin Normal University, China
| | - Thomas N Ferraro
- Department of Biomedical Sciences at CMSRU, Rowan University, NJ 08028, USA
| | - Yong Chen
- Department of Molecular and Cellular Biosciences at Rowan University, Rowan University, NJ 08028, USA
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47
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Saw G, Tang FR. Epigenetic Regulation of the Hippocampus, with Special Reference to Radiation Exposure. Int J Mol Sci 2020; 21:ijms21249514. [PMID: 33327654 PMCID: PMC7765140 DOI: 10.3390/ijms21249514] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/09/2020] [Accepted: 12/12/2020] [Indexed: 01/28/2023] Open
Abstract
The hippocampus is crucial in learning, memory and emotion processing, and is involved in the development of different neurological and neuropsychological disorders. Several epigenetic factors, including DNA methylation, histone modifications and non-coding RNAs, have been shown to regulate the development and function of the hippocampus, and the alteration of epigenetic regulation may play important roles in the development of neurocognitive and neurodegenerative diseases. This review summarizes the epigenetic modifications of various cell types and processes within the hippocampus and their resulting effects on cognition, memory and overall hippocampal function. In addition, the effects of exposure to radiation that may induce a myriad of epigenetic changes in the hippocampus are reviewed. By assessing and evaluating the current literature, we hope to prompt a more thorough understanding of the molecular mechanisms that underlie radiation-induced epigenetic changes, an area which can be further explored.
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48
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Neuronal Firing and Waveform Alterations through Ictal Recruitment in Humans. J Neurosci 2020; 41:766-779. [PMID: 33229500 DOI: 10.1523/jneurosci.0417-20.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 10/29/2020] [Accepted: 11/11/2020] [Indexed: 01/04/2023] Open
Abstract
Analyzing neuronal activity during human seizures is pivotal to understanding mechanisms of seizure onset and propagation. These analyses, however, invariably using extracellular recordings, are greatly hindered by various phenomena that are well established in animal studies: changes in local ionic concentration, changes in ionic conductance, and intense, hypersynchronous firing. The first two alter the action potential waveform, whereas the third increases the "noise"; all three factors confound attempts to detect and classify single neurons. To address these analytical difficulties, we developed a novel template-matching-based spike sorting method, which enabled identification of 1239 single neurons in 27 patients (13 female) with intractable focal epilepsy, that were tracked throughout multiple seizures. These new analyses showed continued neuronal firing with widespread intense activation and stereotyped action potential alterations in tissue that was invaded by the seizure: neurons displayed increased waveform duration (p < 0.001) and reduced amplitude (p < 0.001), consistent with prior animal studies. By contrast, neurons in "penumbral" regions (those receiving intense local synaptic drive from the seizure but without neuronal evidence of local seizure invasion) showed stable waveforms. All neurons returned to their preictal waveforms after seizure termination. We conclude that the distinction between "core" territories invaded by the seizure versus "penumbral" territories is evident at the level of single neurons. Furthermore, the increased waveform duration and decreased waveform amplitude are neuron-intrinsic hallmarks of seizure invasion that impede traditional spike sorting and could be used as defining characteristics of local recruitment.SIGNIFICANCE STATEMENT Animal studies consistently show marked changes in action potential waveform during epileptic discharges, but acquiring similar evidence in humans has proven difficult. Assessing neuronal involvement in ictal events is pivotal to understanding seizure dynamics and in defining clinical localization of epileptic pathology. Using a novel method to track neuronal firing, we analyzed microelectrode array recordings of spontaneously occurring human seizures, and here report two dichotomous activity patterns. In cortex that is recruited to the seizure, neuronal firing rates increase and waveforms become longer in duration and shorter in amplitude as the neurons are recruited to the seizure, while penumbral tissue shows stable action potentials, in keeping with the "dual territory" model of seizure dynamics.
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49
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Botterill JJ, Lu YL, LaFrancois JJ, Bernstein HL, Alcantara-Gonzalez D, Jain S, Leary P, Scharfman HE. An Excitatory and Epileptogenic Effect of Dentate Gyrus Mossy Cells in a Mouse Model of Epilepsy. Cell Rep 2020; 29:2875-2889.e6. [PMID: 31775052 PMCID: PMC6905501 DOI: 10.1016/j.celrep.2019.10.100] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 09/25/2019] [Accepted: 10/24/2019] [Indexed: 12/20/2022] Open
Abstract
The sparse activity of hippocampal dentate gyrus (DG) granule cells (GCs) is thought to be critical for cognition and behavior, whereas excessive DG activity may contribute to disorders such as temporal lobe epilepsy (TLE). Glutamatergic mossy cells (MCs) of the DG are potentially critical to normal and pathological functions of the DG because they can regulate GC activity through innervation of GCs or indirectly through GABAergic neurons. Here, we test the hypothesis that MC excitation of GCs is normally weak, but under pathological conditions, MC excitation of GCs is dramatically strengthened. We show that selectively inhibiting MCs during severe seizures reduced manifestations of those seizures, hippocampal injury, and chronic epilepsy. In contrast, selectively activating MCs was pro-convulsant. Mechanistic in vitro studies using optogenetics further demonstrated the unanticipated ability of MC axons to excite GCs under pathological conditions. These results demonstrate an excitatory and epileptogenic effect of MCs in the DG.
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Affiliation(s)
- Justin J Botterill
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Yi-Ling Lu
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - John J LaFrancois
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Hannah L Bernstein
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; Department of Neuroscience & Physiology, New York University Langone Health, New York, NY 10016, USA
| | - David Alcantara-Gonzalez
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Swati Jain
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Paige Leary
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Helen E Scharfman
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; Department of Neuroscience & Physiology, New York University Langone Health, New York, NY 10016, USA; Department of Psychiatry, New York University Langone Health, New York, NY 10016, USA.
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50
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Neurostimulation stabilizes spiking neural networks by disrupting seizure-like oscillatory transitions. Sci Rep 2020; 10:15408. [PMID: 32958802 PMCID: PMC7506027 DOI: 10.1038/s41598-020-72335-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 08/26/2020] [Indexed: 12/29/2022] Open
Abstract
An improved understanding of the mechanisms underlying neuromodulatory approaches to mitigate seizure onset is needed to identify clinical targets for the treatment of epilepsy. Using a Wilson–Cowan-motivated network of inhibitory and excitatory populations, we examined the role played by intrinsic and extrinsic stimuli on the network’s predisposition to sudden transitions into oscillatory dynamics, similar to the transition to the seizure state. Our joint computational and mathematical analyses revealed that such stimuli, be they noisy or periodic in nature, exert a stabilizing influence on network responses, disrupting the development of such oscillations. Based on a combination of numerical simulations and mean-field analyses, our results suggest that high variance and/or high frequency stimulation waveforms can prevent multi-stability, a mathematical harbinger of sudden changes in network dynamics. By tuning the neurons’ responses to input, stimuli stabilize network dynamics away from these transitions. Furthermore, our research shows that such stabilization of neural activity occurs through a selective recruitment of inhibitory cells, providing a theoretical undergird for the known key role these cells play in both the healthy and diseased brain. Taken together, these findings provide new vistas on neuromodulatory approaches to stabilize neural microcircuit activity.
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