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Neumann AM, Britsch S. Molecular Genetics of Acquired Temporal Lobe Epilepsy. Biomolecules 2024; 14:669. [PMID: 38927072 PMCID: PMC11202058 DOI: 10.3390/biom14060669] [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: 05/07/2024] [Revised: 06/02/2024] [Accepted: 06/03/2024] [Indexed: 06/28/2024] Open
Abstract
An epilepsy diagnosis reduces a patient's quality of life tremendously, and it is a fate shared by over 50 million people worldwide. Temporal lobe epilepsy (TLE) is largely considered a nongenetic or acquired form of epilepsy that develops in consequence of neuronal trauma by injury, malformations, inflammation, or a prolonged (febrile) seizure. Although extensive research has been conducted to understand the process of epileptogenesis, a therapeutic approach to stop its manifestation or to reliably cure the disease has yet to be developed. In this review, we briefly summarize the current literature predominately based on data from excitotoxic rodent models on the cellular events proposed to drive epileptogenesis and thoroughly discuss the major molecular pathways involved, with a focus on neurogenesis-related processes and transcription factors. Furthermore, recent investigations emphasized the role of the genetic background for the acquisition of epilepsy, including variants of neurodevelopmental genes. Mutations in associated transcription factors may have the potential to innately increase the vulnerability of the hippocampus to develop epilepsy following an injury-an emerging perspective on the epileptogenic process in acquired forms of epilepsy.
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Affiliation(s)
| | - Stefan Britsch
- Institute of Molecular and Cellular Anatomy, Ulm University, 89081 Ulm, Germany;
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2
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Leitch B. Parvalbumin Interneuron Dysfunction in Neurological Disorders: Focus on Epilepsy and Alzheimer's Disease. Int J Mol Sci 2024; 25:5549. [PMID: 38791587 PMCID: PMC11122153 DOI: 10.3390/ijms25105549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024] Open
Abstract
Parvalbumin expressing (PV+) GABAergic interneurons are fast spiking neurons that provide powerful but relatively short-lived inhibition to principal excitatory cells in the brain. They play a vital role in feedforward and feedback synaptic inhibition, preventing run away excitation in neural networks. Hence, their dysfunction can lead to hyperexcitability and increased susceptibility to seizures. PV+ interneurons are also key players in generating gamma oscillations, which are synchronized neural oscillations associated with various cognitive functions. PV+ interneuron are particularly vulnerable to aging and their degeneration has been associated with cognitive decline and memory impairment in dementia and Alzheimer's disease (AD). Overall, dysfunction of PV+ interneurons disrupts the normal excitatory/inhibitory balance within specific neurocircuits in the brain and thus has been linked to a wide range of neurodevelopmental and neuropsychiatric disorders. This review focuses on the role of dysfunctional PV+ inhibitory interneurons in the generation of epileptic seizures and cognitive impairment and their potential as targets in the design of future therapeutic strategies to treat these disorders. Recent research using cutting-edge optogenetic and chemogenetic technologies has demonstrated that they can be selectively manipulated to control seizures and restore the balance of neural activity in the brains of animal models. This suggests that PV+ interneurons could be important targets in developing future treatments for patients with epilepsy and comorbid disorders, such as AD, where seizures and cognitive decline are directly linked to specific PV+ interneuron deficits.
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Affiliation(s)
- Beulah Leitch
- Department of Anatomy, School of Biomedical Sciences, Brain Health Research Centre, University of Otago, Dunedin 9016, New Zealand
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3
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Bello ST, Xu S, Li X, Ren J, Jendrichovsky P, Jiang F, Xiao Z, Wan X, Chen X, He J. Visually or auditorily induced seizures involve the activation of nonhippocampal brain areas and hippocampal removal does not alleviate seizures in a mouse model of temporal lobe epilepsy. Epilepsia 2024; 65:218-237. [PMID: 38032046 DOI: 10.1111/epi.17816] [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: 11/17/2022] [Revised: 10/28/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023]
Abstract
OBJECTIVE Several studies have attributed epileptic activities in temporal lobe epilepsy (TLE) to the hippocampus; however, the participation of nonhippocampal neuronal networks in the development of TLE is often neglected. Here, we sought to understand how these nonhippocampal networks are involved in the pathology that is associated with TLE disease. METHODS A kainic acid (KA) model of temporal lobe epilepsy was induced by injecting KA into dorsal hippocampus of C57BL/6J mice. Network activation after spontaneous seizure was assessed using c-Fos expression. Protocols to induce seizure using visual or auditory stimulation were developed, and seizure onset zone (SOZ) and frequency of epileptic spikes were evaluated using electrophysiology. The hippocampus was removed to assess seizure recurrence in the absence of hippocampus. RESULTS Our results showed that cortical and hippocampal epileptic networks are activated during spontaneous seizures. Perturbation of these networks using visual or auditory stimulation readily precipitates seizures in TLE mice; the frequency of the light-induced or noise-induced seizures depends on the induction modality adopted during the induction period. Localization of SOZ revealed the existence of cortical and hippocampal SOZ in light-induced and noise-induced seizures, and the development of local and remote epileptic spikes in TLE occurs during the early stage of the disease. Importantly, we further discovered that removal of the hippocampi does not stop seizure activities in TLE mice, revealing that seizures in TLE mice can occur independent of the hippocampus. SIGNIFICANCE This study has shown that the network pathology that evolves in TLE is not localized to the hippocampus; rather, remote brain areas are also recruited. The occurrence of light-induced or noise-induced seizures and epileptic discharges in epileptic mice is a consequence of the activation of nonhippocampal brain areas. This work therefore demonstrates the fundamental role of nonhippocampal epileptic networks in generating epileptic activities with or without the hippocampus in TLE disease.
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Affiliation(s)
- Stephen Temitayo Bello
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biomedical Science, City University of Hong Kong, Kowloon, Hong Kong
- Center for Regenerative Medicine and Health, Hong Kong Institute of Science and Innovation, Chinese Academy of Sciences, New Territories, Hong Kong
| | - Shenghui Xu
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biomedical Science, City University of Hong Kong, Kowloon, Hong Kong
| | - Xiao Li
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
| | - Junming Ren
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
| | - Peter Jendrichovsky
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biomedical Science, City University of Hong Kong, Kowloon, Hong Kong
| | - Feixu Jiang
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
- Center for Regenerative Medicine and Health, Hong Kong Institute of Science and Innovation, Chinese Academy of Sciences, New Territories, Hong Kong
| | - Zhoujian Xiao
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
| | - Xiaoxiao Wan
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
| | - Xi Chen
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
| | - Jufang He
- Department of Neuroscience, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biomedical Science, City University of Hong Kong, Kowloon, Hong Kong
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4
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Weiler M, Stieger KC, Shroff K, Klein JP, Wood WH, Zhang Y, Chandrasekaran P, Lehrmann E, Camandola S, Long JM, Mattson MP, Becker KG, Rapp PR. Transcriptional changes in the rat brain induced by repetitive transcranial magnetic stimulation. Front Hum Neurosci 2023; 17:1215291. [PMID: 38021223 PMCID: PMC10679736 DOI: 10.3389/fnhum.2023.1215291] [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: 05/01/2023] [Accepted: 10/03/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Transcranial Magnetic Stimulation (TMS) is a noninvasive technique that uses pulsed magnetic fields to affect the physiology of the brain and central nervous system. Repetitive TMS (rTMS) has been used to study and treat several neurological conditions, but its complex molecular basis is largely unexplored. Methods Utilizing three experimental rat models (in vitro, ex vivo, and in vivo) and employing genome-wide microarray analysis, our study reveals the extensive impact of rTMS treatment on gene expression patterns. Results These effects are observed across various stimulation protocols, in diverse tissues, and are influenced by time and age. Notably, rTMS-induced alterations in gene expression span a wide range of biological pathways, such as glutamatergic, GABAergic, and anti-inflammatory pathways, ion channels, myelination, mitochondrial energetics, multiple neuron-and synapse-specific genes. Discussion This comprehensive transcriptional analysis induced by rTMS stimulation serves as a foundational characterization for subsequent experimental investigations and the exploration of potential clinical applications.
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Affiliation(s)
- Marina Weiler
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Kevin C. Stieger
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Kavisha Shroff
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Jessie P. Klein
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - William H. Wood
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Yongqing Zhang
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Prabha Chandrasekaran
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Elin Lehrmann
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Simonetta Camandola
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Jeffrey M. Long
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Mark P. Mattson
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Kevin G. Becker
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Peter R. Rapp
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
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5
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Dawood Rahimi M, Taghi Kheirkhah M, Salehi Fadardi J. Efficacy of tDCS in chronic migraine: A multiprotocol randomized controlled trial. Clin Neurophysiol 2023; 150:119-130. [PMID: 37060843 DOI: 10.1016/j.clinph.2023.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 02/19/2023] [Accepted: 03/12/2023] [Indexed: 04/03/2023]
Abstract
OBJECTIVE Given the prevalence and complicated pathophysiology of migraine, unknown or varied mechanisms of action of available monotherapies or add-on therapies, and their broad range of adverse effects, it is imperative to manage migraine symptoms using a non-invasive, multifunctional, and alternate monotherapy with no negative impacts. METHODS We used a single-blind, randomized, sham-controlled design with baseline, post-test, and 24-weeks follow-up measurements to assess the efficacy of transcranial Direct Current Stimulation (tDCS) in chronic migraine. A total of 150 participants were randomly assigned to the five groups (i.e., allocation ratio of 1:1:1:1:1). Each group received tDCS-intervention for 11 consecutive-weeks (25 sessions; each session = two consecutive montages; each montage = a 20 min duration, 2000 μA intensity). RESULTS The multivariate analysis of variance showed significant (p <.05) reductions in chronic migraine symptoms in the four intervention groups. Compared with the sham (η2 < 0.18) and other protocols (two = η2 > 0.42; three = η2 > 0.40; four = η2 > 0.51), protocol one [l. anode at the right ventrolateral prefrontal cortices, cathode at the left dorsomedial and superior frontal gyrus-first montage; anode at the right primary motor area, cathode at the medial crosstalk of hemispheres-second montage] showed a larger effect size (η2 > 0.59) in the present trial. CONCLUSIONS With the applied protocols of the present trial, tDCS can be used as an effective intervention for the prophylactic and therapeutic treatment of chronic migraine. However, while the second protocol was the least effective, the first was the most effective at reducing migraine symptoms. SIGNIFICANCE To our knowledge, the present trial is the first study to cover the gaps of the earlier ones, including the parameters like the site of stimulation, electrode range distribution and field intensity, number of sessions, session design, and sample size.
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6
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Wang S, Kfoury C, Marion A, Lévesque M, Avoli M. Modulation of in vitro epileptiform activity by optogenetic stimulation of parvalbumin-positive interneurons. J Neurophysiol 2022; 128:837-846. [PMID: 36043700 DOI: 10.1152/jn.00192.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
GABAA signaling is surprisingly involved in the initiation of epileptiform activity since increased interneuron firing, presumably leading to excessive GABA release, often precedes ictal discharges. Field potential theta (4-12 Hz) oscillations, which are thought to mirror the synchronization of interneuron networks, also lead to ictogenesis. However, the exact role of parvalbumin-positive (PV) interneurons in generating theta oscillations linked to epileptiform discharges remains unexplored. We analyzed here the field responses recorded in the CA3, entorhinal cortex (EC) and dentate gyrus (DG) during 8 Hz optogenetic stimulation of PV-positive interneurons in brain slices obtained from PV-ChR2 mice during 4-aminopyridine (4AP) application. This optogenetic protocol triggered similar field oscillations in both control conditions and during 4AP application. However, in the presence of 4AP, optogenetic stimuli also induced: (i) interictal discharges that were associated in all regions with 8 Hz field oscillations; and (ii) low-voltage fast onset ictal discharges. Interictal and ictal events occurred more frequently during optogenetic activation than during periods of no stimulation. 4AP also increased synchronicity during PV-interneuron activation in all three regions. In opsin-negative mice, optogenetic stimulation did not change the rate of both types of epileptiform activity. Our findings suggest that PV-interneuron recruitment at theta (8 Hz) frequency contributes to epileptiform synchronization in limbic structures in the in vitro 4AP model.
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Affiliation(s)
- Siyan Wang
- Montreal Neurological Institute and Hospital and Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - Cristen Kfoury
- Montreal Neurological Institute and Hospital and Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.,Department of Physiology, McGill University, Montreal, QC, Canada
| | - Alexis Marion
- Montreal Neurological Institute and Hospital and Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.,Department of Physiology, McGill University, Montreal, QC, Canada
| | - Maxime Lévesque
- Montreal Neurological Institute and Hospital and Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - Massimo Avoli
- Montreal Neurological Institute and Hospital and Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.,Department of Physiology, McGill University, Montreal, QC, Canada
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7
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de Oliveira FR, da Silva NM, Hamoy M, Crespo-López ME, Ferreira IM, da Silva EO, de Matos Macchi B, do Nascimento JLM. The GABAergic System and Endocannabinoids in Epilepsy and Seizures: What Can We Expect from Plant Oils? Molecules 2022; 27:molecules27113595. [PMID: 35684543 PMCID: PMC9182121 DOI: 10.3390/molecules27113595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/27/2022] [Accepted: 05/30/2022] [Indexed: 02/01/2023] Open
Abstract
Seizures and epilepsy are some of the most common serious neurological disorders, with approximately 80% of patients living in developing/underdeveloped countries. However, about one in three patients do not respond to currently available pharmacological treatments, indicating the need for research into new anticonvulsant drugs (ACDs). The GABAergic system is the main inhibitory system of the brain and has a central role in seizures and the screening of new ACD candidates. It has been demonstrated that the action of agents on endocannabinoid receptors modulates the balance between excitatory and inhibitory neurotransmitters; however, studies on the anticonvulsant properties of endocannabinoids from plant oils are relatively scarce. The Amazon region is an important source of plant oils that can be used for the synthesis of new fatty acid amides, which are compounds analogous to endocannabinoids. The synthesis of such compounds represents an important approach for the development of new anticonvulsant therapies.
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Affiliation(s)
- Fábio Rodrigues de Oliveira
- Programa de Pós-Graduação em Neurociências e Biologia Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil; (F.R.d.O.); (N.M.d.S.); (E.O.d.S.)
- Laboratório de Controle de Qualidade e Bromatologia, Curso de Farmácia, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil
| | - Nágila Monteiro da Silva
- Programa de Pós-Graduação em Neurociências e Biologia Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil; (F.R.d.O.); (N.M.d.S.); (E.O.d.S.)
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
| | - Moisés Hamoy
- Laboratório de Farmacologia e Toxicologia de Produtos Naturais, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
- Programa de Pós-Graduação em Farmacologia e Bioquímica, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
| | - Maria Elena Crespo-López
- Programa de Pós-Graduação em Farmacologia e Bioquímica, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil
| | - Irlon Maciel Ferreira
- Programa de Pós-Graduação em Ciências Farmacêuticas, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil;
- Laboratório de Biocatálise e Síntese Orgânica Aplicada, Departamento de Ciências Exatas e Tecnológicas, Universidade Federal do Amapá, Macapá 68902-280, Brazil
| | - Edilene Oliveira da Silva
- Programa de Pós-Graduação em Neurociências e Biologia Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil; (F.R.d.O.); (N.M.d.S.); (E.O.d.S.)
- Laboratorio de Biologia Estrutural, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil
- Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem (INCT-INBEB), Rio de Janeiro 21941-590, Brazil
| | - Barbarella de Matos Macchi
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
- Programa de Pós-Graduação em Farmacologia e Bioquímica, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
| | - José Luiz Martins do Nascimento
- Programa de Pós-Graduação em Neurociências e Biologia Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil; (F.R.d.O.); (N.M.d.S.); (E.O.d.S.)
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
- Programa de Pós-Graduação em Farmacologia e Bioquímica, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém 66075-110, Brazil;
- Programa de Pós-Graduação em Ciências Farmacêuticas, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil;
- Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação (INCT-NIM), Rio de Janeiro 21040-900, Brazil
- Correspondence:
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8
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Peek AL, Leaver AM, Foster S, Puts NA, Oeltzschner G, Henderson L, Galloway G, Ng K, Refshauge K, Rebbeck T. Increase in ACC GABA+ levels correlate with decrease in migraine frequency, intensity and disability over time. J Headache Pain 2021; 22:150. [PMID: 34903165 PMCID: PMC8903525 DOI: 10.1186/s10194-021-01352-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/03/2021] [Indexed: 11/10/2022] Open
Abstract
Background An imbalance between inhibitory and excitatory neurometabolites has been implicated in chronic pain. Prior work identified elevated levels of Gamma-aminobutyric acid + macromolecules (“GABA+”) using magnetic resonance spectroscopy (MRS) in people with migraine. What is not understood is whether this increase in GABA+ is a cause, or consequence of living with, chronic migraine. Therefore, to further elucidate the nature of the elevated GABA+ levels reported in migraine, this study aimed to observe how GABA+ levels change in response to changes in the clinical characteristics of migraine over time. Methods We observed people with chronic migraine (ICHD-3) over 3-months as their treatment was escalated in line with the Australian Pharmaceutical Benefits Scheme (PBS). Participants underwent an MRS scan and completed questionnaires regarding migraine frequency, intensity (HIT-6) and disability (WHODAS) at baseline and following the routine 3 months treatment escalation to provide the potential for some participants to recover. We were therefore able to monitor changes in brain neurochemistry as clinical characteristics potentially changed over time. Results The results, from 18 participants who completed both baseline and follow-up measures, demonstrated that improvements in migraine frequency, intensity and disability were associated with an increase in GABA+ levels in the anterior cingulate cortex (ACC); migraine frequency (r = − 0.51, p = 0.03), intensity (r = − 0.51, p = 0.03) and disability (r = − 0.53, p = 0.02). However, this was not seen in the posterior cingulate gyrus (PCG). An incidental observation found those who happened to have their treatment escalated with CGRP-monoclonal antibodies (CGRP-mAbs) (n = 10) had a greater increase in ACC GABA+ levels (mean difference 0.54 IU IQR [0.02 to 1.05], p = 0.05) and reduction in migraine frequency (mean difference 10.3 IQR [2.52 to 18.07], p = 0.01) compared to those who did not (n = 8). Conclusion The correlation between an increase in ACC GABA+ levels with improvement in clinical characteristics of migraine, suggest previously reported elevated GABA+ levels may not be a cause of migraine, but a protective mechanism attempting to suppress further migraine attacks. Supplementary Information The online version contains supplementary material available at 10.1186/s10194-021-01352-1.
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Affiliation(s)
- Aimie L Peek
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, 2141, Australia. .,NHMRC Centre of Research Excellence in Road Traffic Injury Recovery, Brisbane, Queensland, Australia.
| | - Andrew M Leaver
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, 2141, Australia
| | - Sheryl Foster
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, 2141, Australia.,Department of Radiology, Westmead Hospital, Hawkesbury Road, Westmead, New South Wales, 2145, Australia
| | - Nicolaas A Puts
- Department of Forensic and Neurodevelopmental Sciences, Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology, and Neuroscience, Kings College London, London, UK
| | - Georg Oeltzschner
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, 21205, USA
| | - Luke Henderson
- School of Medical Sciences, Brain and Mind Centre, University of Sydney, Camperdown, Australia
| | - Graham Galloway
- The University of Queensland, St Lucia, Queensland, 4072, Australia.,Translational Research Institute, 37 Kent Street, Woolloongabba, Queensland, 4102, Australia
| | - Karl Ng
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, 2141, Australia.,Department of Neurology, Royal North Shore Hospital, Reserve Road, St Leonards, New South Wales, 2065, Australia
| | - Kathryn Refshauge
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, 2141, Australia
| | - Trudy Rebbeck
- Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, 2141, Australia.,NHMRC Centre of Research Excellence in Road Traffic Injury Recovery, Brisbane, Queensland, Australia
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9
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Cheng L, Xing Y, Zhang H, Liu R, Lai H, Piao Y, Wang W, Yan X, Li X, Wang J, Li D, Loh HH, Yu T, Zhang G, Yang X. Mechanistic Analysis of Micro-Neurocircuits Underlying the Epileptogenic Zone in Focal Cortical Dysplasia Patients. Cereb Cortex 2021; 32:2216-2230. [PMID: 34664065 DOI: 10.1093/cercor/bhab350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 08/22/2021] [Accepted: 08/23/2021] [Indexed: 11/13/2022] Open
Abstract
We aim to explore the microscopic neurophysiology of focal cortical dysplasia (FCD) induced epileptogenesis in specific macroscopic brain regions, therefore mapping a micro-macro neuronal network that potentially indicates the epileptogenic mechanism. Epileptic and relatively non-epileptic temporal neocortex specimens were resected from FCD and mesial temporal lobe epilepsy (mTLE) patients, respectively. Whole-cell patch-clamping was performed on cells from the seizure onset zone (SOZ) and non-SOZ inside the epileptogenic zone (EZ) of FCD patients, as well as the non-epileptic neocortex of mTLE patients. Microscopic data were recorded, including membrane characteristics, spontaneous synaptic activities, and evoked action potentials. Immunohistochemistry was also performed on parvalbumin-positive (PV+) interneurons. We found that SOZ interneurons exhibited abnormal neuronal expression and distribution as well as reduced overall function compared with non-SOZ and mTLE interneurons. The SOZ pyramidal cells experienced higher excitation but lower inhibition than the mTLE controls, whereas the non-SOZ pyramidal cells exhibited intermediate excitability. Action potential properties of both types of neurons also suggested more synchronized neuronal activity inside the EZ, particularly inside the SOZ. Together, our research provides evidence for a potential neurocircuit underlying SOZ epileptogenesis and non-SOZ seizure susceptibility. Further investigation of this microscopic network may promote understanding of the mechanism of FCD-induced epileptogenesis.
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Affiliation(s)
- Lipeng Cheng
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Yue Xing
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Herui Zhang
- Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China
| | - Ru Liu
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Huanling Lai
- Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China
| | - Yueshan Piao
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Wei Wang
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Xiaoming Yan
- Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Xiaonan Li
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Jiaoyang Wang
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Donghong Li
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China.,Department of Neurology, The Third Affiliated Hospital of Sun Yat-sen University, Guangdong 510635, China
| | - Horace H Loh
- Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China
| | - Tao Yu
- Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Guojun Zhang
- Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China.,Functional Neurosurgery Department, Beijing Children's Hospital, Capital Medical University, Beijing 100045, China
| | - Xiaofeng Yang
- Center of Epilepsy, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100069, China.,Fundamental Research Department, Guangzhou Laboratory, Guangzhou 510700, China.,Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
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10
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Pototskiy E, Dellinger JR, Bumgarner S, Patel J, Sherrerd-Smith W, Musto AE. Brain injuries can set up an epileptogenic neuronal network. Neurosci Biobehav Rev 2021; 129:351-366. [PMID: 34384843 DOI: 10.1016/j.neubiorev.2021.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 08/01/2021] [Indexed: 10/20/2022]
Abstract
Development of epilepsy or epileptogenesis promotes recurrent seizures. As of today, there are no effective prophylactic therapies to prevent the onset of epilepsy. Contributing to this deficiency of preventive therapy is the lack of clarity in fundamental neurobiological mechanisms underlying epileptogenesis and lack of reliable biomarkers to identify patients at risk for developing epilepsy. This limits the development of prophylactic therapies in epilepsy. Here, neural network dysfunctions reflected by oscillopathies and microepileptiform activities, including neuronal hyperexcitability and hypersynchrony, drawn from both clinical and experimental epilepsy models, have been reviewed. This review suggests that epileptogenesis reflects a progressive and dynamic dysfunction of specific neuronal networks which recruit further interconnected groups of neurons, with this resultant pathological network mediating seizure occurrence, recurrence, and progression. In the future, combining spatial and temporal resolution of neuronal non-invasive recordings from patients at risk of developing epilepsy, together with analytics and computational tools, may contribute to determining whether the brain is undergoing epileptogenesis in asymptomatic patients following brain injury.
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Affiliation(s)
- Esther Pototskiy
- Department of Anatomy & Pathology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA; College of Sciences, Old Dominion University, Norfolk, Virginia
| | - Joshua Ryan Dellinger
- Department of Anatomy & Pathology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA
| | - Stuart Bumgarner
- Department of Anatomy & Pathology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA
| | - Jay Patel
- Department of Anatomy & Pathology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA
| | - William Sherrerd-Smith
- Department of Anatomy & Pathology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA
| | - Alberto E Musto
- Department of Anatomy & Pathology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA; Department of Neurology, Eastern Virginia Medical School, Department of Pathology, Norfolk, Virginia, USA.
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11
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Righes Marafiga J, Vendramin Pasquetti M, Calcagnotto ME. GABAergic interneurons in epilepsy: More than a simple change in inhibition. Epilepsy Behav 2021; 121:106935. [PMID: 32035792 DOI: 10.1016/j.yebeh.2020.106935] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 12/20/2022]
Abstract
The pathophysiology of epilepsy has been historically grounded on hyperexcitability attributed to the oversimplified imbalance between excitation (E) and inhibition (I) in the brain. The decreased inhibition is mostly attributed to deficits in gamma-aminobutyric acid-containing (GABAergic) interneurons, the main source of inhibition in the central nervous system. However, the cell diversity, the wide range of spatiotemporal connectivity, and the distinct effects of the neurotransmitter GABA especially during development, must be considered to critically revisit the concept of hyperexcitability caused by decreased inhibition as a key characteristic in the development of epilepsy. Here, we will discuss that behind this known mechanism, there is a heterogeneity of GABAergic interneurons with distinct functions and sources, which have specific roles in controlling the neural network activity within the recruited microcircuit and altered network during the epileptogenic process. This article is part of the Special Issue "NEWroscience 2018.
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Affiliation(s)
- Joseane Righes Marafiga
- Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre 90035-003, RS, Brazil; Graduate Program in Biological Science: Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre 90035-003, RS, Brazil
| | - Mayara Vendramin Pasquetti
- Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre 90035-003, RS, Brazil; Graduate Program in Biological Science: Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre 90035-003, RS, Brazil
| | - Maria Elisa Calcagnotto
- Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre 90035-003, RS, Brazil; Graduate Program in Biological Science: Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre 90035-003, RS, Brazil; Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre 90046-900, RS, Brazil.
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12
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Dos Santos RR, Bernardino TC, da Silva MCM, de Oliveira ACP, Drumond LE, Rosa DV, Massensini AR, Moraes MFD, Doretto MC, Romano-Silva MA, Reis HJ. Neurochemical abnormalities in the hippocampus of male rats displaying audiogenic seizures, a genetic model of epilepsy. Neurosci Lett 2021; 761:136123. [PMID: 34293418 DOI: 10.1016/j.neulet.2021.136123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 07/11/2021] [Accepted: 07/16/2021] [Indexed: 11/17/2022]
Abstract
BACKGROUND Epilepsy is a disorder characterized by recurrent seizures that affects 1% of the population. However, the neurochemical alterations observed in epilepsy are not fully understood. There are different animal models of epilepsy, such as genetic or drug induced. In the present study, we utilize Wistar Audiogenic Rats (WAR), a murine strain that develops seizures in response to high intensity audio stimulation, in order to investigate abnormalities in glutamatergic and GABAergic systems. METHODS Synaptosomes and glial plasmalemmal vesicles were prepared from hippocampus and cortex, respectively. Glutamate and GABA release and uptake were assayed by monitoring the fluorescence and using L-[3H]-radiolabeled compounds. Glutamate and calcium concentration in the synaptosomes were also measured. The expression of neuronal calcium sensor 1 (NCS-1) was determined by western blot. RESULTS Glutamate and GABA release evoked by KCl was decreased in WAR compared to control Wistar rats. Calcium independent release was not considerably different in both groups. The total amount of glutamate of synaptosomes, as well as glutamate uptake by synaptosomes and GPV were also decreased in WAR in comparison with the controls. In addition, [Ca2+]i of hippocampal synaptosomes, as well as NCS-1 expression in the hippocampus, were increased in WAR in comparison with controls. CONCLUSION In conclusion, our results suggest that WAR have important alterations in the glutamatergic and GABAergic pathways, as well as an increased expression of NCS-1 in the hippocampus and inferior colliculus. These alterations may be linked to the spreading of hyperexcitability and recruitment of various brain regions.
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Affiliation(s)
- Rodrigo Ribeiro Dos Santos
- Departamento de Saúde Mental, Faculdade de Medicina, Universidade Federal de Minas Gerais. Av Alfredo Balena 190, CEP 30130-100 Belo Horizonte, MG, Brazil; Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Túlio C Bernardino
- Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Maria Carolina Machado da Silva
- Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Antônio C P de Oliveira
- Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Luciana E Drumond
- Núcleo de Neurociências, Departamento de Biofísica e Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Daniela V Rosa
- Departamento de Saúde Mental, Faculdade de Medicina, Universidade Federal de Minas Gerais. Av Alfredo Balena 190, CEP 30130-100 Belo Horizonte, MG, Brazil
| | - André R Massensini
- Núcleo de Neurociências, Departamento de Biofísica e Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Márcio F D Moraes
- Núcleo de Neurociências, Departamento de Biofísica e Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Maria C Doretto
- Núcleo de Neurociências, Departamento de Biofísica e Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil
| | - Marco A Romano-Silva
- Departamento de Saúde Mental, Faculdade de Medicina, Universidade Federal de Minas Gerais. Av Alfredo Balena 190, CEP 30130-100 Belo Horizonte, MG, Brazil
| | - Helton J Reis
- Laboratório de Neurofarmacologia, Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av Antonio Carlos 6627, Campus Pampulha, CEP 30190-901 Belo Horizonte, MG, Brazil.
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13
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do Canto AM, Donatti A, Geraldis JC, Godoi AB, da Rosa DC, Lopes-Cendes I. Neuroproteomics in Epilepsy: What Do We Know so Far? Front Mol Neurosci 2021; 13:604158. [PMID: 33488359 PMCID: PMC7817846 DOI: 10.3389/fnmol.2020.604158] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/09/2020] [Indexed: 12/12/2022] Open
Abstract
Epilepsies are chronic neurological diseases that affect approximately 2% of the world population. In addition to being one of the most frequent neurological disorders, treatment for patients with epilepsy remains a challenge, because a proportion of patients do not respond to the antiseizure medications that are currently available. This results in a severe economic and social burden for patients, families, and the healthcare system. A characteristic common to all forms of epilepsy is the occurrence of epileptic seizures that are caused by abnormal neuronal discharges, leading to a clinical manifestation that is dependent on the affected brain region. It is generally accepted that an imbalance between neuronal excitation and inhibition generates the synchronic electrical activity leading to seizures. However, it is still unclear how a normal neural circuit becomes susceptible to the generation of seizures or how epileptogenesis is induced. Herein, we review the results of recent proteomic studies applied to investigate the underlying mechanisms leading to epilepsies and how these findings may impact research and treatment for these disorders.
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Affiliation(s)
- Amanda M. do Canto
- Department of Medical Genetics and Genomic Medicine, School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, Brazil
| | - Amanda Donatti
- Department of Medical Genetics and Genomic Medicine, School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, Brazil
| | - Jaqueline C. Geraldis
- Department of Medical Genetics and Genomic Medicine, School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, Brazil
| | - Alexandre B. Godoi
- Department of Medical Genetics and Genomic Medicine, School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, Brazil
| | - Douglas C. da Rosa
- Department of Medical Genetics and Genomic Medicine, School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, Brazil
| | - Iscia Lopes-Cendes
- Department of Medical Genetics and Genomic Medicine, School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, Brazil
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14
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Wang Z, Feng Z, Yuan Y, Zheng L. Suppressing synchronous firing of epileptiform activity by high-frequency stimulation of afferent fibers in rat hippocampus. CNS Neurosci Ther 2020; 27:352-362. [PMID: 33325622 PMCID: PMC7871785 DOI: 10.1111/cns.13535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 11/14/2020] [Accepted: 11/14/2020] [Indexed: 12/18/2022] Open
Abstract
Aims Deep brain stimulation (DBS) is a promising technology for treating epilepsy. However, the efficacy and underlying mechanisms of the high‐frequency stimulation (HFS) utilized by DBS to suppress epilepsy remain uncertain. Previous studies have shown that HFS can desynchronize the firing of neurons. In this study, we investigated whether the desynchronization effects of HFS can suppress epileptiform events. Methods HFS trains with seconds of duration (short) and a minute of duration (long) were applied at the afferent fibers (ie, Schaffer collaterals) of the hippocampal CA1 region in anesthetized rats in vivo. The amplitude and the rate of population spikes (PS) appeared in the downstream of stimulation were calculated to evaluate the intensity of synchronized firing of neuronal populations between short and long HFS groups. A test of paired‐pulse depression (PPD) was used to assess the alteration of inhibitory neuronal circuits. Results The sustained stimulation of a 60‐s long HFS suppressed the afterdischarges that were induced by a 5‐s short HFS to impair the local inhibitions. During the sustained HFS, the mean PS amplitude reduced significantly and the burst firing decreased, while the amount of neuronal firing did not change significantly. The paired‐pulse tests showed that with a similar baseline level of small PS2/PS1 ratio indicating a strong PPD, the 5‐s HFS increased the PS2/PS1 ratio to a value that was significantly greater than the corresponding ratio during sustained HFS, indicating that the PPD impaired by a short HFS may be restored by a sustained HFS. Conclusions The sustained HFS can desynchronize the population firing of epileptiform activity and accelerate a recovery of inhibitions to create a balance between the excitation and the inhibition of local neuronal circuits. The study provides new clues for further understanding the mechanism of DBS and for advancing the clinical application of DBS in treating epilepsy.
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Affiliation(s)
- Zhaoxiang Wang
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China
| | - Zhouyan Feng
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China
| | - Yue Yuan
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China
| | - Lvpiao Zheng
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China
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15
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Re CJ, Batterman AI, Gerstner JR, Buono RJ, Ferraro TN. The Molecular Genetic Interaction Between Circadian Rhythms and Susceptibility to Seizures and Epilepsy. Front Neurol 2020; 11:520. [PMID: 32714261 PMCID: PMC7344275 DOI: 10.3389/fneur.2020.00520] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 05/12/2020] [Indexed: 12/19/2022] Open
Abstract
Seizure patterns observed in patients with epilepsy suggest that circadian rhythms and sleep/wake mechanisms play some role in the disease. This review addresses key topics in the relationship between circadian rhythms and seizures in epilepsy. We present basic information on circadian biology, but focus on research studying the influence of both the time of day and the sleep/wake cycle as independent but related factors on the expression of seizures in epilepsy. We review studies investigating how seizures and epilepsy disrupt expression of core clock genes, and how disruption of clock mechanisms impacts seizures and the development of epilepsy. We focus on the overlap between mechanisms of circadian-associated changes in SCN neuronal excitability and mechanisms of epileptogenesis as a means of identifying key pathways and molecules that could represent new targets or strategies for epilepsy therapy. Finally, we review the concept of chronotherapy and provide a perspective regarding its application to patients with epilepsy based on their individual characteristics (i.e., being a “morning person” or a “night owl”). We conclude that better understanding of the relationship between circadian rhythms, neuronal excitability, and seizures will allow both the identification of new therapeutic targets for treating epilepsy as well as more effective treatment regimens using currently available pharmacological and non-pharmacological strategies.
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Affiliation(s)
- Christopher J Re
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Alexander I Batterman
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Jason R Gerstner
- Department of Biomedical Sciences, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| | - Russell J Buono
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Thomas N Ferraro
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
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16
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Expression of TRPC3 in cortical lesions from patients with focal cortical dysplasia. Neurosci Lett 2020; 724:134880. [PMID: 32135163 DOI: 10.1016/j.neulet.2020.134880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/10/2020] [Accepted: 02/29/2020] [Indexed: 11/20/2022]
Abstract
Focal cortical dysplasia (FCD) is one of the main causes of medically intractable epilepsy. Some studies have reported that transient receptor potential canonical channel 3 (TRPC3) may play an important role in the occurrence of seizures. In this study, we investigated the expression patterns of TRPC3 in different types of FCD. Forty-five FCD specimens and 12 control samples from autopsies were used in our study. Western blotting, immunohistochemistry, and immunofluorescence staining were employed to detect protein expression and distribution. The amount of TRPC3 protein was markedly elevated in the FCD group. The immunohistochemistry results revealed that TRPC3 staining was strong in the malformed cells and microcolumns. Most of the TRPC3-positive cells were colabeled with glutamatergic and GABAergic markers. The overexpression and altered cellular distribution of TRPC3 in the FCD samples suggest that TRPC3 may be related to epileptogenesis in FCD.
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17
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Chauvière L. Potential causes of cognitive alterations in temporal lobe epilepsy. Behav Brain Res 2020; 378:112310. [DOI: 10.1016/j.bbr.2019.112310] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 10/15/2019] [Accepted: 10/15/2019] [Indexed: 12/11/2022]
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18
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Butler CR, Boychuk JA, Pomerleau F, Alcala R, Huettl P, Ai Y, Jakobsson J, Whiteheart SW, Gerhardt GA, Smith BN, Slevin JT. Modulation of epileptogenesis: A paradigm for the integration of enzyme-based microelectrode arrays and optogenetics. Epilepsy Res 2019; 159:106244. [PMID: 31816591 DOI: 10.1016/j.eplepsyres.2019.106244] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 10/22/2019] [Accepted: 11/22/2019] [Indexed: 02/03/2023]
Abstract
BACKGROUND Genesis of acquired epilepsy includes transformations spanning genetic-to- network-level modifications, disrupting the regional excitatory/inhibitory balance. Methodology concurrently tracking changes at multiple levels is lacking. Here, viral vectors are used to differentially express two opsin proteins in neuronal populations within dentate gyrus (DG) of hippocampus. When activated, these opsins induced excitatory or inhibitory neural output that differentially affected neural networks and epileptogenesis. In vivo measures included behavioral observation coupled to real-time measures of regional glutamate flux using ceramic-based amperometric microelectrode arrays (MEAs). RESULTS Using MEA technology, phasic increases of extracellular glutamate were recorded immediately upon application of blue light/488 nm to DG of rats previously transfected with an AAV 2/5 vector containing an (excitatory) channelrhodopsin-2 transcript. Rats receiving twice-daily 30-sec light stimulation to DG ipsilateral to viral transfection progressed through Racine seizure stages. AAV 2/5 (inhibitory) halorhodopsin-transfected rats receiving concomitant amygdalar kindling and DG light stimuli were kindled significantly more slowly than non-stimulated controls. In in vitro slice preparations, both excitatory and inhibitory responses were independently evoked in dentate granule cells during appropriate light stimulation. Latency to response and sensitivity of responses suggest a degree of neuron subtype-selective functional expression of the transcripts. CONCLUSIONS This study demonstrates the potential for coupling MEA technology and optogenetics for real-time neurotransmitter release measures and modification of seizure susceptibility in animal models of epileptogenesis. This microelectrode/optogenetic technology could prove useful for characterization of network and system level dysfunction in diseases involving imbalanced excitatory/inhibitory control of neuron populations and guide development of future treatment strategies.
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Affiliation(s)
- Corwin R Butler
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States
| | - Jeffery A Boychuk
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Epilepsy Center, University of Kentucky, Lexington, KY, 40536, United States
| | - Francois Pomerleau
- Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Brain Restoration Center, University of Kentucky, Lexington, KY, 40356, United States
| | - Ramona Alcala
- Department of Neurology, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States
| | - Peter Huettl
- Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Brain Restoration Center, University of Kentucky, Lexington, KY, 40356, United States
| | - Yi Ai
- Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States
| | - Johan Jakobsson
- Wallenburg Neuroscience Center, Lund Stem Cell Center, Lund University, Lund, Sweden
| | - Sidney W Whiteheart
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, United States; Veterans Affairs Medical Center, Lexington, KY, 40536, United States
| | - Greg A Gerhardt
- Epilepsy Center, University of Kentucky, Lexington, KY, 40536, United States; Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky, Lexington, KY, 40536, United States; Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Department of Neurology, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Brain Restoration Center, University of Kentucky, Lexington, KY, 40356, United States
| | - Bret N Smith
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Epilepsy Center, University of Kentucky, Lexington, KY, 40536, United States; Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky, Lexington, KY, 40536, United States; Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States
| | - John T Slevin
- Epilepsy Center, University of Kentucky, Lexington, KY, 40536, United States; Department of Neurology, College of Medicine, University of Kentucky, Lexington, KY, 40536, United States; Veterans Affairs Medical Center, Lexington, KY, 40536, United States; Brain Restoration Center, University of Kentucky, Lexington, KY, 40356, United States.
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19
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Cepeda C, Levinson S, Nariai H, Yazon VW, Tran C, Barry J, Oikonomou KD, Vinters HV, Fallah A, Mathern GW, Wu JY. Pathological high frequency oscillations associate with increased GABA synaptic activity in pediatric epilepsy surgery patients. Neurobiol Dis 2019; 134:104618. [PMID: 31629890 DOI: 10.1016/j.nbd.2019.104618] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/22/2019] [Accepted: 09/19/2019] [Indexed: 11/25/2022] Open
Abstract
Pathological high-frequency oscillations (HFOs), specifically fast ripples (FRs, >250 Hz), are pathognomonic of an active epileptogenic zone. However, the origin of FRs remains unknown. Here we explored the correlation between FRs recorded with intraoperative pre-resection electrocorticography (ECoG) and spontaneous synaptic activity recorded ex vivo from cortical tissue samples resected for the treatment of pharmacoresistant epilepsy. The cohort included 47 children (ages 0.22-9.99 yr) with focal cortical dysplasias (CD types I and II), tuberous sclerosis complex (TSC) and non-CD pathologies. Whole-cell patch clamp recordings were obtained from pyramidal neurons and interneurons in cortical regions that were positive or negative for pathological HFOs, defined as FR band oscillations (250-500 Hz) at ECoG. The frequency of spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and IPSCs, respectively) was compared between HFO+ and HFO- regions. Regardless of pathological substrate, regions positive for FRs displayed significantly increased frequencies of sIPSCs compared with regions negative for FRs. In contrast, the frequency of sEPSCs was similar in both regions. In about one third of cases (n = 17), pacemaker GABA synaptic activity (PGA) was observed. In the vast majority (n = 15), PGA occurred in HFO+ areas. Further, fast-spiking interneurons displayed signs of hyperexcitability exclusively in HFO+ areas. These results indicate that, in pediatric epilepsy patients, increased GABA synaptic activity is associated with interictal FRs in the epileptogenic zone and suggest an active role of GABAergic interneurons in the generation of pathological HFOs. Increased GABA synaptic activity could serve to dampen excessive excitability of cortical pyramidal neurons in the epileptogenic zone, but it could also promote neuronal network synchrony.
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Affiliation(s)
- Carlos Cepeda
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA.
| | - Simon Levinson
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Hiroki Nariai
- Division of Pediatric Neurology, Mattel Children's Hospital, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Vannah-Wila Yazon
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Conny Tran
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Joshua Barry
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Katerina D Oikonomou
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Harry V Vinters
- Section of Neuropathology, Department of Pathology and Laboratory Medicine and Department of Neurology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Aria Fallah
- Department of Neurosurgery, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Gary W Mathern
- IDDRC, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA; Department of Neurosurgery, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Joyce Y Wu
- Division of Pediatric Neurology, Mattel Children's Hospital, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
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20
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McAvoy KM, Rajamohamed Sait H, Marsh G, Peterson M, Reynolds TL, Gagnon J, Geisler S, Leach P, Roberts C, Cahir-McFarland E, Ransohoff RM, Crotti A. Cell-autonomous and non-cell autonomous effects of neuronal BIN1 loss in vivo. PLoS One 2019; 14:e0220125. [PMID: 31408457 PMCID: PMC6692034 DOI: 10.1371/journal.pone.0220125] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 07/09/2019] [Indexed: 01/25/2023] Open
Abstract
BIN1 is the most important risk locus for Late Onset Alzheimer’s Disease (LOAD), after ApoE. BIN1 AD-associated SNPs correlate with Tau deposition as well as with brain atrophy. Furthermore, the level of neuronal-specific BIN1 isoform 1 protein is decreased in sporadic AD cases in parallel with neuronal loss, despite an overall increase in BIN1 total mRNA. To address the relationship between reduction of BIN1 and neuronal cell loss in the context of Tau pathology, we knocked-down endogenous murine Bin1 via stereotaxic injection of AAV-Bin1 shRNA in the hippocampus of mice expressing Tau P301S (PS19). We observed a statistically significant reduction in the number of neurons in the hippocampus of mice injected with AAV-Bin1 shRNA in comparison with mice injected with AAV control. To investigate whether neuronal loss is due to deletion of Bin1 selectively in neurons in presence Tau P301S, we bred Bin1flox/flox with Thy1-Cre and subsequently with PS19 mice. Mice lacking neuronal Bin1 and expressing Tau P301S showed increased mortality, without increased neuropathology, when compared to neuronal Bin1 and Tau P301S-expressing mice. The loss of Bin1 isoform 1 resulted in reduced excitability in primary neurons in vitro, reduced neuronal c-fos expression as well as in altered microglia transcriptome in vivo. Taken together, our data suggest that the contribution of genetic variation in BIN1 locus to AD risk could result from a cell-autonomous reduction of neuronal excitability due to Bin1 decrease, exacerbated by the presence of aggregated Tau, coupled with a non-cell autonomous microglia activation.
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Affiliation(s)
| | | | | | | | | | - Jake Gagnon
- Biogen, Cambridge, MA, United States of America
| | | | | | | | | | - Richard M Ransohoff
- Department of Cell Biology, Harvard Medical School, Boston, MA, United States of America
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21
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Cavarsan CF, Malheiros J, Hamani C, Najm I, Covolan L. Is Mossy Fiber Sprouting a Potential Therapeutic Target for Epilepsy? Front Neurol 2018; 9:1023. [PMID: 30555406 PMCID: PMC6284045 DOI: 10.3389/fneur.2018.01023] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 11/13/2018] [Indexed: 11/13/2022] Open
Abstract
Mesial temporal lobe epilepsy (MTLE) caused by hippocampal sclerosis is one of the most frequent focal epilepsies in adults. It is characterized by focal seizures that begin in the hippocampus, sometimes spread to the insulo-perisylvian regions and may progress to secondary generalized seizures. Morphological alterations in hippocampal sclerosis are well defined. Among them, hippocampal sclerosis is characterized by prominent cell loss in the hilus and CA1, and abnormal mossy fiber sprouting (granular cell axons) into the dentate gyrus inner molecular layer. In this review, we highlight the role of mossy fiber sprouting in seizure generation and hippocampal excitability and discuss the response of alternative treatment strategies in terms of MFS and spontaneous recurrent seizures in models of TLE (temporal lobe epilepsy).
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Affiliation(s)
- Clarissa F Cavarsan
- Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Jackeline Malheiros
- Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Clement Hamani
- Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil.,Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Imad Najm
- Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Luciene Covolan
- Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil.,Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH, United States
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22
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Camporeze B, Manica BA, Bonafé GA, Ferreira JJC, Diniz AL, de Oliveira CTP, Mathias Junior LR, de Aguiar PHP, Ortega MM. Optogenetics: the new molecular approach to control functions of neural cells in epilepsy, depression and tumors of the central nervous system. Am J Cancer Res 2018; 8:1900-1918. [PMID: 30416844 PMCID: PMC6220144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/14/2018] [Indexed: 06/09/2023] Open
Abstract
The optogenetic tools have been described as valuable techniques to study neural activity through light stimulation, as well as potential neuromodulator approaches in the management of several central nervous system (CNS) diseases. Since the first bacteriorhodopsin protein described as a single-component light-activated regulator of transmembrane ion flow description, in 1980's, the focus has been on channel proteins for neurobiology; however, the advances in engineering techniques showed involvement changes in cellular biological behavior in several types of proteins involved in cell cytoskeleton regulation, motility and gene expression. Although the use of this technology has been published in many papers, a question still remains regarding real results and potential clinical applicability in CNS diseases, as well as the publications scarcity that systematically analyses the published results. Lastly, the aim of this review is to discuss the experimental results, molecular mechanisms and potential clinical applications of optogenetic tools in epilepsy and depression treatment, as well as its applicability in the treatment of CNS tumors.
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Affiliation(s)
- Bruno Camporeze
- Postgraduate Program in Health Science, Laboratory of Cellular and Molecular Biology and Bioactive Compounds, São Francisco University (USF)Bragança Paulista-SP, Brazil
- Postgraduate Program in Health Science, Department of Neurosurgery, Institute of Medical Assistance of The State Public Servant (IAMSPE)São Paulo-SP, Brazil
| | - Bruno Alcântara Manica
- Departament of Neurology, Medical School University Pontifical University Catholic of São Paulo (PUCSP)Sorocaba-SP, Brazil
| | - Gabriel Alves Bonafé
- Postgraduate Program in Health Science, Laboratory of Cellular and Molecular Biology and Bioactive Compounds, São Francisco University (USF)Bragança Paulista-SP, Brazil
| | | | - Aurélio Lourenço Diniz
- Departament of Neurology, Medical School University Pontifical University Catholic of São Paulo (PUCSP)Sorocaba-SP, Brazil
| | | | | | - Paulo Henrique Pires de Aguiar
- Postgraduate Program in Health Science, Department of Neurosurgery, Institute of Medical Assistance of The State Public Servant (IAMSPE)São Paulo-SP, Brazil
- Departament of Neurology, Medical School University Pontifical University Catholic of São Paulo (PUCSP)Sorocaba-SP, Brazil
- Departament of Neurosurgery, Hospital Santa PaulaSão Paulo-SP, Brazil
- Department of Research and Innovation, Laboratory of Cellular and Molecular Biology, Medical School of ABC (FMABC)Santo André-SP, Brazil
| | - Manoela Marques Ortega
- Postgraduate Program in Health Science, Laboratory of Cellular and Molecular Biology and Bioactive Compounds, São Francisco University (USF)Bragança Paulista-SP, Brazil
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23
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Symmank J, Bayer C, Schmidt C, Hahn A, Pensold D, Zimmer-Bensch G. DNMT1 modulates interneuron morphology by regulating Pak6 expression through crosstalk with histone modifications. Epigenetics 2018; 13:536-556. [PMID: 29912614 DOI: 10.1080/15592294.2018.1475980] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Epigenetic mechanisms of gene regulation, including DNA methylation and histone modifications, call increasing attention in the context of development and human health. Thereby, interactions between DNA methylating enzymes and histone modifications tremendously multiply the spectrum of potential regulatory functions. Epigenetic networks are critically involved in the establishment and functionality of neuronal circuits that are composed of gamma-aminobutyric acid (GABA)-positive inhibitory interneurons and excitatory principal neurons in the cerebral cortex. We recently reported a crucial role of the DNA methyltransferase 1 (DNMT1) during the migration of immature POA-derived cortical interneurons by promoting the migratory morphology through repression of Pak6. However, the DNMT1-dependent regulation of Pak6 expression appeared to occur independently of direct DNA methylation. Here, we show that in addition to its DNA methylating activity, DNMT1 can act on gene transcription by modulating permissive H3K4 and repressive H3K27 trimethylation in developing inhibitory interneurons, similar to what was found in other cell types. In particular, the transcriptional control of Pak6, interactions of DNMT1 with the Polycomb-repressor complex 2 (PCR2) core enzyme EZH2, mediating repressive H3K27 trimethylations at regulatory regions of the Pak6 gene locus. Similar to what was observed upon Dnmt1 depletion, inhibition of EZH2 caused elevated Pak6 expression levels accompanied by increased morphological complexity, which was rescued by siRNA-mediated downregulation of Pak6 expression. Together, our data emphasise the relevance of DNMT1-dependent crosstalk with histone tail methylation for transcriptional control of genes like Pak6 required for proper cortical interneuron migration.
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Affiliation(s)
- Judit Symmank
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Cathrin Bayer
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Christiane Schmidt
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Anne Hahn
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Daniel Pensold
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Geraldine Zimmer-Bensch
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany.,b Institute for Biology II , Division of Functional Epigenetics in the Animal Model, RWTH Aachen University , Aachen , Germany
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24
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Lucchese G, Stahl B. Peptide Sharing Between Viruses and DLX Proteins: A Potential Cross-Reactivity Pathway to Neuropsychiatric Disorders. Front Neurosci 2018; 12:150. [PMID: 29618965 PMCID: PMC5871705 DOI: 10.3389/fnins.2018.00150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 02/26/2018] [Indexed: 12/24/2022] Open
Abstract
The present study seeks to determine potential associations between viral infections and neuropsychiatric diseases. To address this issue, we investigated the peptide commonalities between viruses that have been related to psychiatric and neurological disorders—such as rubella, human immunodeficiency virus, and herpesviruses—and human distal-less homeobox (DLX) proteins expressed in developing brain—namely, DLX1, DLX2, DLX5, and DLX6. Peptide matching analyses revealed a high degree of pentapeptide sharing. From an immunological perspective, this overlap is relevant because pentapeptides are endowed with immunogenicity and antigenicity—that is, they are immune determinants. Moreover, infection-induced immune cross-reactions might have functional, spatial, and temporal implications related to the functions and expression patterns of DLX1 and DLX5 in the fetal and adult human brain. In sum, our data support the hypothesis that viral infections may be linked to neuropsychiatric diseases through autoimmune cross-reactions caused by molecular mimicry between viral proteins and brain-specific DLX self-antigens.
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Affiliation(s)
- Guglielmo Lucchese
- Brain Language Laboratory, Freie Universität Berlin, Berlin, Germany.,Department of Neurology, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Benjamin Stahl
- Department of Neurology, Universitätsmedizin Greifswald, Greifswald, Germany.,Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.,Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Psychologische Hochschule Berlin, Berlin, Germany
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