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Park KI. Understanding epileptogenesis from molecules to network alteration. ENCEPHALITIS 2024; 4:47-54. [PMID: 38886161 PMCID: PMC11237188 DOI: 10.47936/encephalitis.2024.00038] [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: 04/11/2024] [Accepted: 05/14/2024] [Indexed: 06/20/2024] Open
Abstract
Epilepsy is characterized by recurrent seizures. Following an initial insult, a latent period precedes the onset of spontaneous seizures, a process referred to as epileptogenesis. This period plays a critical role in halting the progression toward epilepsy before the onset of abnormal molecular and network alterations. In this study, the fundamental concepts of epileptogenesis as well as the associated molecular and cellular targets are reviewed.
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Affiliation(s)
- Kyung-Il Park
- Department of Neurology, Seoul National University Hospital Healthcare System Gangnam Center, Seoul National University College of Medicine, Seoul, Korea
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2
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Normoyle KP, Lillis KP, Staley KJ. Synthesis and Characterization of a Novel Concentration-Independent Fluorescent Chloride Indicator, ABP-Dextran, Optimized for Extracellular Chloride Measurement. Biomolecules 2024; 14:77. [PMID: 38254677 PMCID: PMC10813347 DOI: 10.3390/biom14010077] [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: 10/16/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/24/2024] Open
Abstract
GABA, the primary inhibitory neurotransmitter, stimulates GABAA receptors (GABAARs) to increase the chloride conductance of the cytosolic membrane. The driving forces for membrane chloride currents are determined by the local differences between intracellular and extracellular chloride concentrations (Cli and Clo, respectively). While several strategies exist for the measurement of Cli, the field lacks tools for non-invasive measurement of Clo. We present the design and development of a fluorescent lifetime imaging (FLIM)-compatible small molecule, N(4-aminobutyl)phenanthridiunium (ABP) with the brightness, spectral features, sensitivity to chloride, and selectivity versus other anions to serve as a useful probe of Clo. ABP can be conjugated to dextran to ensure extracellular compartmentalization, and a second chloride-insensitive counter-label can be added for ratiometric imaging. We validate the utility of this novel sensor series in two sensor concentration-independent modes: FLIM or ratiometric intensity-based imaging.
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Affiliation(s)
- Kieran P. Normoyle
- Massachusetts General Hospital, Department of Neurology, 55 Fruit Street, Boston, MA 02114, USA; (K.P.N.); (K.P.L.)
- Harvard Medical School, Department of Neurology, 77 Louis Pasteur Avenue, Boston, MA 02115, USA
| | - Kyle P. Lillis
- Massachusetts General Hospital, Department of Neurology, 55 Fruit Street, Boston, MA 02114, USA; (K.P.N.); (K.P.L.)
- Harvard Medical School, Department of Neurology, 77 Louis Pasteur Avenue, Boston, MA 02115, USA
| | - Kevin J. Staley
- Massachusetts General Hospital, Department of Neurology, 55 Fruit Street, Boston, MA 02114, USA; (K.P.N.); (K.P.L.)
- Harvard Medical School, Department of Neurology, 77 Louis Pasteur Avenue, Boston, MA 02115, USA
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3
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Morris G, Avoli M, Bernard C, Connor K, de Curtis M, Dulla CG, Jefferys JGR, Psarropoulou C, Staley KJ, Cunningham MO. Can in vitro studies aid in the development and use of antiseizure therapies? A report of the ILAE/AES Joint Translational Task Force. Epilepsia 2023; 64:2571-2585. [PMID: 37642296 DOI: 10.1111/epi.17744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/11/2023] [Accepted: 08/11/2023] [Indexed: 08/31/2023]
Abstract
In vitro preparations (defined here as cultured cells, brain slices, and isolated whole brains) offer a variety of approaches to modeling various aspects of seizures and epilepsy. Such models are particularly amenable to the application of anti-seizure compounds, and consequently are a valuable tool to screen the mechanisms of epileptiform activity, mode of action of known anti-seizure medications (ASMs), and the potential efficacy of putative new anti-seizure compounds. Despite these applications, all disease models are a simplification of reality and are therefore subject to limitations. In this review, we summarize the main types of in vitro models that can be used in epilepsy research, describing key methodologies as well as notable advantages and disadvantages of each. We argue that a well-designed battery of in vitro models can form an effective and potentially high-throughput screening platform to predict the clinical usefulness of ASMs, and that in vitro models are particularly useful for interrogating mechanisms of ASMs. To conclude, we offer several key recommendations that maximize the potential value of in vitro models in ASM screening. This includes the use of multiple in vitro tests that can complement each other, carefully combined with in vivo studies, the use of tissues from chronically epileptic (rather than naïve wild-type) animals, and the integration of human cell/tissue-derived preparations.
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Affiliation(s)
- Gareth Morris
- Division of Neuroscience, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| | - Massimo Avoli
- Montreal Neurological Institute-Hospital and Departments of Neurology & Neurosurgery, McGill University, Montréal, Quebec, Canada
- Department of Physiology, McGill University, Montréal, Quebec, Canada
| | - Christophe Bernard
- Inserm, INS, Institut de Neurosciences des Systèmes, Aix Marseille Univ, Marseille, France
| | - Kate Connor
- Discipline of Physiology, School of Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Marco de Curtis
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Chris G Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - John G R Jefferys
- Department of Physiology, 2nd Medical School, Motol, Charles University, Prague, Czech Republic
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Caterina Psarropoulou
- Laboratory of Animal and Human Physiology, Department of Biological Applications and Technology, Faculty of Health Sciences, University of Ioannina, Ioannina, Greece
| | - Kevin J Staley
- Neurology Department, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Mark O Cunningham
- Discipline of Physiology, School of Medicine, Trinity College Dublin, Dublin 2, Ireland
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4
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Neuberger B, Mello FK, Mallmann MP, da Costa Sobral KG, Fighera MR, Royes LFF, Furian AF, Sampaio TB, Oliveira MS. Beneficial Effects of Rosmarinic Acid In Vitro and In Vivo Models of Epileptiform Activity Induced by Pilocarpine. Brain Sci 2023; 13:brainsci13020289. [PMID: 36831832 PMCID: PMC9954593 DOI: 10.3390/brainsci13020289] [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: 01/10/2023] [Revised: 02/04/2023] [Accepted: 02/06/2023] [Indexed: 02/11/2023] Open
Abstract
Epilepsy is characterized by a predisposition to generate recurrent and spontaneous seizures; it affects millions of people worldwide. Status epilepticus (SE) is a severe type of seizure. In this context, screening potential treatments is very important. In the present study, we evaluated the beneficial effects of rosmarinic acid (RA) in pilocarpine-induced in vitro and in vivo models of epileptiform activity. Using an in vitro model in combined entorhinal cortex-hippocampal from Wistar rats we evaluated the effects of RA (10 µg/mL) on the lactate release and a glucose fluorescent analogue, 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NDBG), after incubation in high potassium aCSF supplemented or not with pilocarpine. In the in vivo model, SE was induced in male C57BL/6 mice by pilocarpine. At 1, 24, and 48 h after the end of SE mice were treated with RA (30 mg/kg/v.o.). We evaluated the neuromotor impairment by neuroscore tests and protein carbonyl levels in the cerebral cortex. In both in vitro models, RA was able to decrease the stimulated lactate release, while no effect on 2-NBDG uptake was found. RA has beneficial effects in models of epileptiform activity in vivo and in vitro. We found that RA treatment attenuated SE-induced neuromotor impairment at the 48 h timepoint. Moreover, post-SE treatment with RA decreased levels of protein carbonyls in the cerebral cortex of mice when compared to their vehicle-treated counterparts. Importantly, RA was effective in a model of SE which is relevant for the human condition. The present data add to the literature on the biological effects of RA, which could be a good candidate for add-on therapy in epilepsy.
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Affiliation(s)
- Bruna Neuberger
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | - Fernanda Kulinski Mello
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | - Michele Pereira Mallmann
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | | | - Michele Rechia Fighera
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
- Graduate Program in Biological Sciences: Toxicological Biochemistry, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | - Luiz Fernando Freire Royes
- Graduate Program in Biological Sciences: Toxicological Biochemistry, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | - Ana Flávia Furian
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
- Graduate Program in Food Science and Technology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | - Tuane Bazanella Sampaio
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
| | - Mauro Schneider Oliveira
- Graduate Program in Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, Brazil
- Correspondence: ; Tel.: +55-55-3220-9378
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5
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Lau LA, Staley KJ, Lillis KP. In vitro ictogenesis is stochastic at the single neuron level. Brain 2022; 145:531-541. [PMID: 34431994 PMCID: PMC9014754 DOI: 10.1093/brain/awab312] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/13/2021] [Accepted: 07/30/2021] [Indexed: 11/14/2022] Open
Abstract
Seizure initiation is the least understood and most disabling element of epilepsy. Studies of ictogenesis require high speed recordings at cellular resolution in the area of seizure onset. However, in vivo seizure onset areas cannot be determined at the level of resolution necessary to enable such studies. To circumvent these challenges, we used novel GCaMP7-based calcium imaging in the organotypic hippocampal slice culture model of post-traumatic epilepsy in mice. Organotypic hippocampal slice cultures generate spontaneous, recurrent seizures in a preparation in which it is feasible to image the activity of the entire network (with no unseen inputs existing). Chronic calcium imaging of the entire hippocampal network, with paired electrophysiology, revealed three patterns of seizure onset: (i) low amplitude fast activity; (ii) sentinel spike; and (iii) spike burst and low amplitude fast activity onset. These patterns recapitulate common features of human seizure onset, including low voltage fast activity and spike discharges. Weeks-long imaging of seizure activity showed a characteristic evolution in onset type and a refinement of the seizure onset zone. Longitudinal tracking of individual neurons revealed that seizure onset is stochastic at the single neuron level, suggesting that seizure initiation activates neurons in non-stereotyped sequences seizure to seizure. This study demonstrates for the first time that transitions to seizure are not initiated by a small number of neuronal 'bad actors' (such as overly connected hub cells), but rather by network changes which enable the onset of pathology among large populations of neurons.
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Affiliation(s)
- Lauren A Lau
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Kevin J Staley
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Kyle P Lillis
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA.,Harvard Medical School, Boston, MA 02115, USA
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6
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Fusco F, Perottoni S, Giordano C, Riva A, Iannone LF, De Caro C, Russo E, Albani D, Striano P. The microbiota‐gut‐brain axis and epilepsy from a multidisciplinary perspective: clinical evidence and technological solutions for improvement of
in vitro
preclinical models. Bioeng Transl Med 2022; 7:e10296. [PMID: 35600638 PMCID: PMC9115712 DOI: 10.1002/btm2.10296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/10/2022] [Accepted: 01/15/2022] [Indexed: 11/09/2022] Open
Affiliation(s)
- Federica Fusco
- Dipartimento di Chimica, materiali e ingegneria chimica "Giulio Natta" Politecnico di Milano Milan Italy
| | - Simone Perottoni
- Dipartimento di Chimica, materiali e ingegneria chimica "Giulio Natta" Politecnico di Milano Milan Italy
| | - Carmen Giordano
- Dipartimento di Chimica, materiali e ingegneria chimica "Giulio Natta" Politecnico di Milano Milan Italy
| | - Antonella Riva
- Paediatric Neurology and Muscular Disease Unit, IRCCS Istituto Giannina Gaslini Genova Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health Università degli Studi di Genova Genova Italy
| | | | - Carmen De Caro
- Science of Health Department Magna Graecia University Catanzaro Italy
| | - Emilio Russo
- Science of Health Department Magna Graecia University Catanzaro Italy
| | - Diego Albani
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS Milan Italy
| | - Pasquale Striano
- Paediatric Neurology and Muscular Disease Unit, IRCCS Istituto Giannina Gaslini Genova Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health Università degli Studi di Genova Genova Italy
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7
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Dulla CG, Pitkänen A. Novel Approaches to Prevent Epileptogenesis After Traumatic Brain Injury. Neurotherapeutics 2021; 18:1582-1601. [PMID: 34595732 PMCID: PMC8608993 DOI: 10.1007/s13311-021-01119-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2021] [Indexed: 02/04/2023] Open
Abstract
Traumatic brain injury (TBI) is defined as an alteration in brain function or other evidence of brain pathology caused by an external force. When epilepsy develops following TBI, it is known as post-traumatic epilepsy (PTE). PTE occurs in a subset of patients suffering from different types and severities of TBI, occurs more commonly following severe injury, and greatly impacts the quality of life for patients recovering from TBI. Similar to other types of epilepsy, PTE is often refractory to drug treatment with standard anti-seizure drugs. No therapeutic approaches have proven successful in the clinic to prevent the development of PTE. Therefore, novel treatment strategies are needed to stop the development of PTE and improve the quality of life for patients after TBI. Interestingly, TBI represents an excellent clinical opportunity for intervention to prevent epileptogenesis as typically the time of initiation of epileptogenesis (i.e., TBI) is known, the population of at-risk patients is large, and animal models for preclinical studies of mechanisms and treatment targets are available. If properly identified and treated, there is a true opportunity to prevent epileptogenesis after TBI and stop seizures from ever happening. With that goal in mind, here we review previous attempts to prevent PTE both in animal studies and in humans, we examine how biomarkers could enable better-targeted therapeutics, and we discuss how genetic variation may predispose individuals to PTE. Finally, we highlight exciting new advances in the field that suggest that there may be novel approaches to prevent PTE that should be considered for further clinical development.
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Affiliation(s)
- Chris G Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA.
| | - Asla Pitkänen
- A. I. Virtanen Institute, University of Eastern Finland, 70 211, Kuopio, Finland.
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Löscher W, Klein P. New approaches for developing multi-targeted drug combinations for disease modification of complex brain disorders. Does epilepsy prevention become a realistic goal? Pharmacol Ther 2021; 229:107934. [PMID: 34216705 DOI: 10.1016/j.pharmthera.2021.107934] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/16/2021] [Accepted: 06/16/2021] [Indexed: 12/14/2022]
Abstract
Over decades, the prevailing standard in drug discovery was the concept of designing highly selective compounds that act on individual drug targets. However, more recently, multi-target and combinatorial drug therapies have become an important treatment modality in complex diseases, including neurodegenerative diseases such as Alzheimer's and Parkinson's disease. The development of such network-based approaches is facilitated by the significant advance in our understanding of the pathophysiological processes in these and other complex brain diseases and the adoption of modern computational approaches in drug discovery and repurposing. However, although drug combination therapy has become an effective means for the symptomatic treatment of many complex diseases, the holy grail of identifying clinically effective disease-modifying treatments for neurodegenerative and other brain diseases remains elusive. Thus, despite extensive research, there remains an urgent need for novel treatments that will modify the progression of the disease or prevent its development in patients at risk. Here we discuss recent approaches with a focus on multi-targeted drug combinations for prevention or modification of epilepsy. Over the last ~10 years, several novel promising multi-targeted therapeutic approaches have been identified in animal models. We envision that synergistic combinations of repurposed drugs as presented in this review will be demonstrated to prevent epilepsy in patients at risk within the next 5-10 years.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| | - Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, MD, USA
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Ghiasvand S, Dussourd CR, Liu J, Song Y, Berdichevsky Y. Variability of seizure-like activity in an in vitro model of epilepsy depends on the electrical recording method. Heliyon 2020; 6:e05587. [PMID: 33299935 PMCID: PMC7702014 DOI: 10.1016/j.heliyon.2020.e05587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/12/2020] [Accepted: 11/19/2020] [Indexed: 11/30/2022] Open
Abstract
Background Hippocampal and cortical slice-based models are widely used to study seizures and epilepsy. Seizure detection and quantification are essential components for studying mechanisms of epilepsy and assessing therapeutic interventions. To obtain meaningful signals and maximize experimental throughput, variability should be minimized. Some electrical recording methods require insertion of an electrode into neuronal tissue, change in slice chemical microenvironment, and transients in temperature and pH. These perturbations can cause acute and long-term alterations of the neuronal network which may be reflected in the variability of the recorded signal. New method In this study we investigated the effect of experimental perturbations in three local field potential (LFP) recording methods including substrate micro-wires (s-MWs), multiple electrode arrays (MEAs), and inserted micro wire electrodes (i-MW). These methods enabled us to isolate effects of different perturbations. We used organotypic hippocampal slices (OHCs) as an in-vitro model of posttraumatic epilepsy. To investigate the effect of the disturbances caused by the recording method on the paroxysmal events, we introduced jitter analysis, which is sensitive to small differences in the seizure spike timing. Results Medium replacement can introduce long-lasting perturbations. Electrode insertion increased variability on a shorter time scale. OHCs also underwent spontaneous state transitions characterized by transient increases in variability. Comparison with existing methods This new method of seizure waveform analysis allows for more sensitive assessment of variability of ictal events than simply measuring seizure frequency and duration. Conclusion We demonstrated that some of the variability in OHC recordings are due to experimental perturbations while some are spontaneous and independent of recording method.
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Affiliation(s)
| | | | - Jing Liu
- Electrical Engineering Lehigh University, United States
| | - Yu Song
- Bioengineering Lehigh University, United States
| | - Yevgeny Berdichevsky
- Bioengineering Lehigh University, United States.,Electrical Engineering Lehigh University, United States
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Hasan MF, Ghiasvand S, Wang H, Miwa JM, Berdichevsky Y. Neural layer self-assembly in geometrically confined rat and human 3D cultures. Biofabrication 2019; 11:045011. [PMID: 31247598 DOI: 10.1088/1758-5090/ab2d3f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Neurological disorders affect millions of Americans and this number is expected to rise with the aging population. Development of drugs to treat these disorders may be facilitated by improved in vitro models that faithfully reproduce salient features of the relevant brain regions. Current 3D culture methods face challenges with reliably reproducing microarchitectural features of brain morphology such as cortical or hippocampal layers. In this work, polydimethylsiloxane (PDMS) mini-wells were used to create low aspect ratio, adherent 3D constructs where neurons self-assemble into layers. Layer self-assembly was determined to depend on the size of the PDMS mini-well. Layer formation occurred in cultures composed of primary rat cortical neurons or human induced pluripotent stem cell-derived neurons and astrocytes and was robust and reproducible. Layered 3D constructs were found to have spontaneous neural activity characterized by long bursts similar to activity in the developing cortex. The responses of layered 3D cultures to drugs were more similar to in vivo data than those of 2D cultures. 3D constructs created with this method may be thus suitable as in vitro models for drug discovery for neurological disorders.
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Affiliation(s)
- Md Fayad Hasan
- Department of Electrical and Computer Engineering, Lehigh University, Bethlehem, PA 18015, United States of America
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11
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Carvill GL, Dulla CG, Lowenstein DH, Brooks-Kayal AR. The path from scientific discovery to cures for epilepsy. Neuropharmacology 2019; 167:107702. [PMID: 31301334 DOI: 10.1016/j.neuropharm.2019.107702] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/05/2019] [Accepted: 07/06/2019] [Indexed: 02/06/2023]
Abstract
The epilepsies are a complex group of disorders that can be caused by a myriad of genetic and acquired factors. As such, identifying interventions that will prevent development of epilepsy, as well as cure the disorder once established, will require a multifaceted approach. Here we discuss the progress in scientific discovery propelling us towards this goal, including identification of genetic risk factors and big data approaches that integrate clinical and molecular 'omics' datasets to identify common pathophysiological signatures and biomarkers. We discuss the many animal and cellular models of epilepsy, what they have taught us about pathophysiology, and the cutting edge cellular, optogenetic, chemogenetic and anti-seizure drug screening approaches that are being used to find new cures in these models. Finally, we reflect on the work that still needs to be done towards identify at-risk individuals early, targeting and stopping epileptogenesis, and optimizing promising treatment approaches. Ultimately, developing and implementing cures for epilepsy will require a coordinated and immense effort from clinicians and basic scientists, as well as industry, and should always be guided by the needs of individuals affected by epilepsy and their families. This article is part of the special issue entitled 'New Epilepsy Therapies for the 21st Century - From Antiseizure Drugs to Prevention, Modification and Cure of Epilepsy'.
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Affiliation(s)
- Gemma L Carvill
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA.
| | - Chris G Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA.
| | - Dan H Lowenstein
- Department of Neurology, University of California, San Francisco, CA, 94941, USA
| | - Amy R Brooks-Kayal
- Department of Pediatrics and Neurology, University of Colorado School of Medicine and Children's Hospital Colorado, Aurora, CO, 80045, USA
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12
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Abstract
This review describes developments in epilepsy research during the last 3 to 4 decades that focused on the dentate gyrus (DG) and its role in temporal lobe epilepsy (TLE). The emphasis is on basic research in laboratory animals and is chronological, starting with hypotheses that attracted a lot of attention in the 1980s. Then experiments are described that addressed the questions, as well as new methods that often made the experiments possible. In addition, where new questions arose and the implications for clinical epilepsy are discussed.
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Affiliation(s)
- Helen E. Scharfman
- Departments of Child & Adolescent Psychiatry, Neuroscience &
Physiology, and Psychiatry, New York University Langone Health, New York, NY, USA
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric
Research, Orangeburg, NY, USA
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13
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Kinase Inhibitors with Antiepileptic Properties Identified with a Novel in Vitro Screening Platform. Int J Mol Sci 2019; 20:ijms20102502. [PMID: 31117204 PMCID: PMC6566965 DOI: 10.3390/ijms20102502] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 05/14/2019] [Accepted: 05/15/2019] [Indexed: 02/06/2023] Open
Abstract
Kinase signaling plays an important role in acquired epilepsy, but only a small percentage of the total kinome has been investigated in this context. A major roadblock that prevents the systematic investigation of the contributions of kinase signaling networks is the slow speed of experiments designed to test the chronic effects of target inhibition in epilepsy models. We developed a novel in vitro screening platform based on microwire recordings from an organotypic hippocampal culture model of acquired epilepsy. This platform enables the direct, parallel determination of the effects of compounds on spontaneous epileptiform activity. The platform also enables repeated recordings from the same culture over two-week long experiments. We screened 45 kinase inhibitors and quantified their effects on seizure duration, the frequency of paroxysmal activity, and electrographic load. We identified several inhibitors with previously unknown antiepileptic properties. We also used kinase inhibition profile cross-referencing to identify kinases that are inhibited by seizure-suppressing compounds, but not by compounds that had no effect on seizures.
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14
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Liu J, Sternberg AR, Ghiasvand S, Berdichevsky Y. Epilepsy-on-a-Chip System for Antiepileptic Drug Discovery. IEEE Trans Biomed Eng 2019; 66:1231-1241. [PMID: 30235116 PMCID: PMC6585967 DOI: 10.1109/tbme.2018.2871415] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Hippocampal slice cultures spontaneously develop chronic epilepsy several days after slicing and are used as an in vitro model of post-traumatic epilepsy. Here, we describe a hybrid microfluidic-microelectrode array (μflow-MEA) technology that incorporates a microfluidic perfusion network and electrodes into a miniaturized device for hippocampal slice culture based antiepileptic drug discovery. METHODS Field potential simulation was conducted to help optimize the electrode design to detect a seizure-like population activity. Epilepsy-on-a-chip model was validated by chronic electrical recording, neuronal survival quantification, and anticonvulsant test. To demonstrate the application of μflow-MEA in drug discovery, we utilized a two-stage screening platform to identify potential targets for antiepileptic drugs. In Stage I, lactate and lactate dehydrogenase biomarker assays were performed to identify potential drug candidates. In Stage II, candidate compounds were retested with μflow-MEA-based chronic electrical assay to provide electrophysiological confirmation of biomarker results. RESULTS AND CONCLUSION We screened 12 receptor tyrosine kinases inhibitors, and EGFR/ErbB-2 and cFMS inhibitors were identified as novel antiepileptic compounds. SIGNIFICANCE This epilepsy-on-a-chip system provides the means for rapid dissection of complex signaling pathways in epileptogenesis, paving the way for high-throughput antiepileptic drug discovery.
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Affiliation(s)
- Jing Liu
- Department of Electrical and Computer Engineering, Lehigh University, Bethlehem, PA, USA. She is now with University of California, San Francisco, CA, USA
| | - Anna R. Sternberg
- IDEAS Program, Lehigh University, Bethlehem, PA, USA. She is now with Georgetown University, Washington D.C., USA
| | | | - Yevgeny Berdichevsky
- Department of Electrical and Computer Engineering and Department of Bioengineering, Lehigh University, Bethlehem, PA, USA
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Impact of a selective cyclooxygenase-2 inhibitor, celecoxib, on cortical excitability and electrophysiological properties of the brain in healthy volunteers: A randomized, double-blind, placebo-controlled study. PLoS One 2019; 14:e0212689. [PMID: 30794658 PMCID: PMC6386435 DOI: 10.1371/journal.pone.0212689] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/31/2019] [Indexed: 01/12/2023] Open
Abstract
The inflammatory response is considered a defence mechanism against physical or infectious insults and is prevalent within the central nervous system. Seizures also result in a robust inflammatory cascade, leading to enhanced activation of excitatory synaptic networks. Ample evidence based on animal models of epilepsy has demonstrated that celecoxib, a highly selective inhibitor of cyclooxygenase-2, has anticonvulsant effects. We aimed to evaluate the impact of celecoxib on the cortical excitability and electrophysiological properties of the brain in healthy humans. Electroencephalography (EEG) or transmagnetic stimulation (TMS) was used to measure neurophysiological activity. Forty healthy volunteers were randomized to 4 groups (n = 10 in each group): 1) celecoxib and EEG, 2) placebo and EEG, 3) celecoxib and TMS, and 4) placebo and TMS. For the EEG study, resting EEG was performed at baseline just before administering 400 mg of celecoxib or placebo and repeated 4 hours after administration. The subjects took 200 mg of celecoxib or placebo twice a day for 7 subsequent days, and a third EEG was conducted 4 hours after the final dose. Power spectra were compared at each time point. For the TMS study, the resting motor threshold (RMT), motor evoked potential (MEP) peak-to-peak amplitude, and cortical silent period (CSP) were measured at baseline and after taking 200 mg of celecoxib or placebo twice a day for 7 days. Celecoxib did not significantly change brain activity in the EEG study. However, the sum of power recorded from all electrodes tended to increase in the celecoxib group only at 4 hours after administration (p = 0.06). In detail, one dose of celecoxib (400 mg) transiently and significantly increased the alpha band power recorded in the frontal and parietal areas as well as in the whole brain (p = 0.049, 0.017, and 0.014, respectively) and the beta frequency in the central and parietal regions (p = 0.013 and 0.005, respectively), whereas the placebo did not. This effect was abolished after 7 days of treatment. In the TMS study, we found no statistically significant change in the RMT, MEP peak-to-peak amplitude or CSP. This evidence suggests that celecoxib transiently alters the electrophysiological properties of the brain but does not suppress neuronal excitability in healthy humans.
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Dulla CG, Janigro D, Jiruska P, Raimondo JV, Ikeda A, Lin CCK, Goodkin HP, Galanopoulou AS, Bernard C, de Curtis M. How do we use in vitro models to understand epileptiform and ictal activity? A report of the TASK1-WG4 group of the ILAE/AES Joint Translational Task Force. Epilepsia Open 2018; 3:460-473. [PMID: 30525115 PMCID: PMC6276782 DOI: 10.1002/epi4.12277] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2018] [Indexed: 02/06/2023] Open
Abstract
In vitro brain tissue preparations allow the convenient and affordable study of brain networks and have allowed us to garner molecular, cellular, and electrophysiologic insights into brain function with a detail not achievable in vivo. Preparations from both rodent and human postsurgical tissue have been utilized to generate in vitro electrical activity similar to electrographic activity seen in patients with epilepsy. A great deal of knowledge about how brain networks generate various forms of epileptiform activity has been gained, but due to the multiple in vitro models and manipulations used, there is a need for a standardization across studies. Here, we describe epileptiform patterns generated using in vitro brain preparations, focusing on issues and best practices pertaining to recording, reporting, and interpretation of the electrophysiologic patterns observed. We also discuss criteria for defining in vitro seizure‐like patterns (i.e., ictal) and interictal discharges. Unifying terminologies and definitions are proposed. We suggest a set of best practices for reporting in vitro studies to favor both efficient across‐lab comparisons and translation to in vivo models and human studies.
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Affiliation(s)
- Chris G Dulla
- Department of Neuroscience Tufts University School of Medicine Boston Massachusetts U.S.A
| | - Damir Janigro
- Flocel Inc. and Case Western Reserve University Cleveland Ohio U.S.A
| | - Premysl Jiruska
- Department of Developmental Epileptology Institute of Physiology of the Czech Academy of Sciences Prague Czechia
| | - Joseph V Raimondo
- Division of Cell Biology and Neuroscience Institute Department of Human Biology Faculty of Health Sciences University of Cape Town Cape Town South Africa
| | - Akio Ikeda
- Department of Epilepsy, Movement Disorders and Physiology Kyoto University Graduate School of Medicine Kyoto Japan
| | - Chou-Ching K Lin
- Department of Neurology National Cheng Kung University Hospital College of Medicine National Cheng Kung University Tainan Taiwan
| | - Howard P Goodkin
- The Departments of Neurology and Pediatrics University of Virginia Charlottesville Virginia U.S.A
| | - Aristea S Galanopoulou
- Laboratory of Developmental Epilepsy Saul R. Korey Department of Neurology Isabelle Rapin Division of Child Neurology Dominick P. Purpura Department of Neuroscience Albert Einstein College of Medicine, and Einstein/Montefiore Epilepsy Center Montefiore Medical Center Bronx New York U.S.A
| | | | - Marco de Curtis
- Epilepsy Unit Fondazione IRCCS Istituto Neurologico Carlo Besta Milano Italy
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Chong SA, Balosso S, Vandenplas C, Szczesny G, Hanon E, Claes K, Van Damme X, Danis B, Van Eyll J, Wolff C, Vezzani A, Kaminski RM, Niespodziany I. Intrinsic Inflammation Is a Potential Anti-Epileptogenic Target in the Organotypic Hippocampal Slice Model. Neurotherapeutics 2018; 15:470-488. [PMID: 29464573 PMCID: PMC5935638 DOI: 10.1007/s13311-018-0607-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Understanding the mechanisms of epileptogenesis is essential to develop novel drugs that could prevent or modify the disease. Neuroinflammation has been proposed as a promising target for therapeutic interventions to inhibit the epileptogenic process that evolves from traumatic brain injury. However, it remains unclear whether cytokine-related pathways, particularly TNFα signaling, have a critical role in the development of epilepsy. In this study, we investigated the role of innate inflammation in an in vitro model of post-traumatic epileptogenesis. We combined organotypic hippocampal slice cultures, representing an in vitro model of post-traumatic epilepsy, with multi-electrode array recordings to directly monitor the development of epileptiform activity and to examine the concomitant changes in cytokine release, cell death, and glial cell activation. We report that synchronized ictal- and interictal-like activities spontaneously evolve in this culture. Dynamic changes in the release of the pro-inflammatory cytokines IL-1β, TNFα, and IL-6 were observed throughout the culture period (3 to 21 days in vitro) with persistent activation of microglia and astrocytes. We found that neutralizing TNFα with a polyclonal antibody significantly reduced ictal discharges, and this effect lasted for 1 week after antibody washout. Neither phenytoin nor an anti-IL-6 polyclonal antibody was efficacious in inhibiting the development of epileptiform activity. Our data show a sustained effect of the anti-TNFα antibody on the ictal progression in organotypic hippocampal slice cultures supporting the critical role of inflammatory mediators in epilepsy and establishing a proof-of-principle evidence for the utility of this preparation to test the therapeutic effects of anti-inflammatory treatments.
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Affiliation(s)
- Seon-Ah Chong
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium.
| | - Silvia Balosso
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | | | - Gregory Szczesny
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Etienne Hanon
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Kasper Claes
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Xavier Van Damme
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Bénédicte Danis
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Jonathan Van Eyll
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Christian Wolff
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Annamaria Vezzani
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | - Rafal M Kaminski
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
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18
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Chong SA, Balosso S, Vandenplas C, Szczesny G, Hanon E, Claes K, Van Damme X, Danis B, Van Eyll J, Wolff C, Vezzani A, Kaminski RM, Niespodziany I. Intrinsic Inflammation Is a Potential Anti-Epileptogenic Target in the Organotypic Hippocampal Slice Model. Neurotherapeutics 2018; 15:470-488. [PMID: 29464573 DOI: 10.1007/s13311-018-0607-6/figures/7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023] Open
Abstract
Understanding the mechanisms of epileptogenesis is essential to develop novel drugs that could prevent or modify the disease. Neuroinflammation has been proposed as a promising target for therapeutic interventions to inhibit the epileptogenic process that evolves from traumatic brain injury. However, it remains unclear whether cytokine-related pathways, particularly TNFα signaling, have a critical role in the development of epilepsy. In this study, we investigated the role of innate inflammation in an in vitro model of post-traumatic epileptogenesis. We combined organotypic hippocampal slice cultures, representing an in vitro model of post-traumatic epilepsy, with multi-electrode array recordings to directly monitor the development of epileptiform activity and to examine the concomitant changes in cytokine release, cell death, and glial cell activation. We report that synchronized ictal- and interictal-like activities spontaneously evolve in this culture. Dynamic changes in the release of the pro-inflammatory cytokines IL-1β, TNFα, and IL-6 were observed throughout the culture period (3 to 21 days in vitro) with persistent activation of microglia and astrocytes. We found that neutralizing TNFα with a polyclonal antibody significantly reduced ictal discharges, and this effect lasted for 1 week after antibody washout. Neither phenytoin nor an anti-IL-6 polyclonal antibody was efficacious in inhibiting the development of epileptiform activity. Our data show a sustained effect of the anti-TNFα antibody on the ictal progression in organotypic hippocampal slice cultures supporting the critical role of inflammatory mediators in epilepsy and establishing a proof-of-principle evidence for the utility of this preparation to test the therapeutic effects of anti-inflammatory treatments.
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Affiliation(s)
- Seon-Ah Chong
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium.
| | - Silvia Balosso
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | | | - Gregory Szczesny
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Etienne Hanon
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Kasper Claes
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Xavier Van Damme
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Bénédicte Danis
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Jonathan Van Eyll
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Christian Wolff
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Annamaria Vezzani
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | - Rafal M Kaminski
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
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Strengthening the Case for Epilepsy Drug Development: Bridging Experiences from the Alzheimer’s Disease Field—An Opinion. Neurochem Res 2017; 42:2099-2115. [DOI: 10.1007/s11064-017-2300-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/08/2017] [Accepted: 05/09/2017] [Indexed: 11/29/2022]
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