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Balikci A, Eryilmaz U, Guler VK, Ilbay G. Tactile stimulation of young WAG/Rij rats prevents development of depression but not absence epilepsy. Front Behav Neurosci 2024; 18:1433431. [PMID: 38993266 PMCID: PMC11236540 DOI: 10.3389/fnbeh.2024.1433431] [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: 05/15/2024] [Accepted: 06/17/2024] [Indexed: 07/13/2024] Open
Abstract
Investigations in Wistar Albino Glaxo from Rijswijk (WAG/Rij) rats that are susceptible to genetic absence epilepsy have demonstrated that environmental modifications affect absence seizures. Previously, we showed that neonatal tactile stimulations produce disease-modifying effect on genetically determined absence epilepsy and associated depression in Wag/Rij rats. The study presented here examined the effect of TS during late ontogenesis (adolescence and young adulthood) on epilepsy and depression outcomes in this genetically epileptic rat strain. On postnatal day (PND) 38, male WAG/Rij rats randomly were assigned to either the tactile stimulation (TS), handled or control group (unhandled) with 8 animals in each group. Following a 7-day adaptation period to their new surroundings, the animals were submitted to tactile stimulation from PND 45 to PND 90, five days per week, for 5 min daily. The tactile-stimulated rat was removed from its cage, placed on the experimenter's lap, and had its neck and back gently stroked by the researcher. The handled rats were taken to another cage and left alone for 5 min daily from PND 45 to PND 90. The control rats were left undisturbed in their home cage, except for regular cage cleaning. After PND 90, all rats were left undisturbed until behavioral testing and EEG recording. When the animals were 7 months old, they were subjected to the sucrose consumption test (SCT) and the forced swimming test (FST). Electroencephalogram (EEG) recordings were made at 8 months of age in order to measure electroencephalographic seizure activity, thus, the spike-wave discharges (SWDs). Tactile-stimulated rats showed increased sucrose consumption and number of approaches to the sucrose solution in the SCT when compared with the handled and control rats. In the FST, rats in TS group showed lower immobility time and greater immobility latency, active swimming time and diving frequency than the handled and control rats. The duration and the number of seizures were not different amongst the groups. The data obtained suggest that TS in young rats is able to prevent depression in WAG/Rij rats.
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Affiliation(s)
- Aymen Balikci
- Department of Physiology, Faculty of Medicine, Kocaeli University, İzmit, Türkiye
| | - Ugur Eryilmaz
- Department of Physiology, Faculty of Medicine, Kocaeli University, İzmit, Türkiye
| | - Vildan Keles Guler
- Department of Physiology, Faculty of Medicine, Kocaeli University, İzmit, Türkiye
| | - Gul Ilbay
- Department of Physiology, Faculty of Medicine, Kocaeli University, İzmit, Türkiye
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Tiryaki ES, Arslan G, Günaydın C, Ayyıldız M, Ağar E. The role of HCN channels on the effects of T-type calcium channels and GABA A receptors in the absence epilepsy model of WAG/Rij rats. Pflugers Arch 2024; 476:337-350. [PMID: 38159130 DOI: 10.1007/s00424-023-02900-1] [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: 10/10/2023] [Revised: 12/07/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Abstract
In this study we used ivabradine (IVA), a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker, to identify its effect on spike-wave discharges (SWDs); and aimed to determine the role of IVA on the effects of T-type calcium channel blocker NNC 55-0396, GABAA receptor agonist muscimol and antagonist bicuculline in male WAG/Rij rats. After tripolar electrodes for electrocorticogram (ECoG) recordings were placed on the WAG/Rij rats' skulls, 5, 10, and 20 mg/kg IVA were intraperitoneally administered for 7 consecutive days and ECoG recordings were obtained on days 0th, 3rd, 6th, and 7th for three hours before and after injections. While acute injection of 5, 10, and 20 mg/kg IVA did not affect the total number and the mean duration of SWDs, subacute administration (7 days) of IVA decreased the SWDs parameters 24 hours after the 7th injection. Interestingly, when IVA was administered again 24 hours after the 6th IVA injection, it increased the SWDs parameters. Western-blot analyses showed that HCN1 and HCN2 expressions decreased and HCN4 increased in the 5-month-old WAG/Rij rats compared to the 1-month-old WAG/Rij and 5-month-old native Wistar rats, while subacute IVA administration increased the levels of HCN1 and HCN2 channels, except HCN4. Subacute administration of IVA reduced the antiepileptic activity of NNC, while the proepileptic activity of muscimol and the antiepileptic activity of bicuculline were abolished. It might be suggested that subacute IVA administration reduces absence seizures by changing the HCN channel expressions in WAG/Rij rats, and this affects the T-type calcium channels and GABAA receptors.
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Affiliation(s)
- Emre Soner Tiryaki
- Department of Physiology, Faculty of Medicine, University of Ondokuz Mayıs, Samsun, Türkiye
| | - Gökhan Arslan
- Department of Physiology, Faculty of Medicine, University of Ondokuz Mayıs, Samsun, Türkiye.
| | - Caner Günaydın
- Department of Pharmacology, Faculty of Medicine, University of Samsun, Samsun, Türkiye
| | - Mustafa Ayyıldız
- Department of Physiology, Faculty of Medicine, University of Ondokuz Mayıs, Samsun, Türkiye
| | - Erdal Ağar
- Department of Physiology, Faculty of Medicine, University of Ondokuz Mayıs, Samsun, Türkiye
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Brigo F, Zelano J, Abraira L, Bentes C, Ekdahl CT, Lattanzi S, Ingvar Lossius M, Redfors P, Rouhl RPW, Russo E, Sander JW, Vogrig A, Wickström R. Proceedings of the "International Congress on Structural Epilepsy & Symptomatic Seizures" (STESS, Gothenburg, Sweden, 29-31 March 2023). Epilepsy Behav 2024; 150:109538. [PMID: 38039602 DOI: 10.1016/j.yebeh.2023.109538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 11/09/2023] [Accepted: 11/09/2023] [Indexed: 12/03/2023]
Affiliation(s)
- Francesco Brigo
- Innovation, Research and Teaching Service (SABES-ASDAA), Teaching Hospital of the Paracelsus Medical Private University (PMU), Bolzano, Italy.
| | - Johan Zelano
- Department of Neurology, Sahlgrenska University Hospital, Gothenburg, Sweden; Institute of Neuroscience and Physiology, Department of Clinical Neuroscience, Sahlgrenska Academy, Gothenburg University, Sweden; Wallenberg Center of Molecular and Translational Medicine, Gothenburg University, Sweden
| | - Laura Abraira
- Neurology Department, Epilepsy Unit, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain; Epilepsy Unit, Neurology Department, Vall d'Hebron University Hospital, Barcelona, Spain; Epilepsy Research Group, Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
| | - Carla Bentes
- Neurophysiological Monitoring Unit - EEG/Sleep Laboratory, Refractory Epilepsy Reference Centre (member of EpiCARE), Centro Hospitalar Universitário Lisboa Norte, Lisbon, Portugal; Centro de Estudos Egas Moniz, Faculty of Medicine, Lisbon University, Lisbon, Portugal
| | - Christine T Ekdahl
- Division of Clinical Neurophysiology and Department of Clinical Sciences, Lund University, Sweden; Lund Epilepsy Center, Department of Clinical Sciences, Lund University, Sweden
| | - Simona Lattanzi
- Neurological Clinic, Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - Morten Ingvar Lossius
- National Centre for Epilepsy, Division of Clinical Neuroscience, Oslo University Hospital, Member of the ERN EpiCARE, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Petra Redfors
- Department of Neurology, Member of the ERN EpiCARE, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Rob P W Rouhl
- Department of Neurology, Maastricht University Medical Centre+, Maastricht, The Netherlands; Academic Centre for Epileptology Kempenhaeghe/MUMC+ Heeze and Maastricht, The Netherlands; School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Emilio Russo
- Science of Health Department, University Magna Grecia of Catanzaro, Italy
| | - Josemir W Sander
- Department of Clinical & Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, UK; Centre for Epilepsy, Chalfont St Peter, Bucks., SL9 0RJ, United Kingdom; Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede 2103 SW, The Netherlands; Neurology Department, West of China Hospital, Sichuan University, Chengdu 610041, China
| | - Alberto Vogrig
- Department of Medicine (DAME), University of Udine, Udine, Italy; Clinical Neurology, Department of Head-Neck and Neuroscience, Azienda Sanitaria Universitaria Friuli Centrale (ASU FC), Udine, Italy
| | - Ronny Wickström
- Neuropediatric Unit, Karolinska University Hospital and Karolinska Institutet, Stockholm, Sweden
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Jiruska P, Freestone D, Gnatkovsky V, Wang Y. An update on the seizures beget seizures theory. Epilepsia 2023; 64 Suppl 3:S13-S24. [PMID: 37466948 DOI: 10.1111/epi.17721] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 07/17/2023] [Accepted: 07/17/2023] [Indexed: 07/20/2023]
Abstract
Seizures beget seizures is a longstanding theory that proposed that seizure activity can impact the structural and functional properties of the brain circuits in ways that contribute to epilepsy progression and the future occurrence of seizures. Originally proposed by Gowers, this theory continues to be quoted in the pathophysiology of epilepsy. We critically review the existing data and observations on the consequences of recurrent seizures on brain networks and highlight a range of factors that speak for and against the theory. The existing literature demonstrates clearly that ictal activity, especially if recurrent, induces molecular, structural, and functional changes including cell loss, connectivity reorganization, changes in neuronal behavior, and metabolic alterations. These changes have the potential to modify the seizure threshold, contribute to disease progression, and recruit wider areas of the epileptic network into epileptic activity. Repeated seizure activity may, thus, act as a pathological positive-feedback mechanism that increases seizure likelihood. On the other hand, the time course of self-limited epilepsies and the presence of seizure remission in two thirds of epilepsy cases and various chronic epilepsy models oppose the theory. Experimental work showed that seizures could induce neural changes that increase the seizure threshold and decrease the risk of a subsequent seizure. Due to the complex nature of epilepsies, it is wrong to consider only seizures as the key factor responsible for disease progression. Epilepsy worsening can be attributed to the various forms of interictal epileptiform activity or underlying disease mechanisms. Although seizure activity can negatively impact brain structure and function, the "seizures beget seizures" theory should not be used dogmatically but with extreme caution.
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Affiliation(s)
- Premysl Jiruska
- Department of Physiology, Second Faculty of Medicine, Charles University, Prague, Czech Republic
| | | | - Vadym Gnatkovsky
- Department of Epileptology, University Hospital Bonn, Bonn, Germany
| | - Yujiang Wang
- Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
- Interdisciplinary Computing and Complex BioSystems Group, School of Computing Science, Newcastle University, Newcastle upon Tyne, UK
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Crunelli V, David F, Morais TP, Lorincz ML. HCN channels and absence seizures. Neurobiol Dis 2023; 181:106107. [PMID: 37001612 DOI: 10.1016/j.nbd.2023.106107] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/20/2023] [Accepted: 03/25/2023] [Indexed: 03/31/2023] Open
Abstract
Hyperpolarization-activation cyclic nucleotide-gated (HCN) channels were for the first time implicated in absence seizures (ASs) when an abnormal Ih (the current generated by these channels) was reported in neocortical layer 5 neurons of a mouse model. Genetic studies of large cohorts of children with Childhood Absence Epilepsy (where ASs are the only clinical symptom) have identified only 3 variants in HCN1 (one of the genes that code for the 4 HCN channel isoforms, HCN1-4), with one (R590Q) mutation leading to loss-of-function. Due to the multi-faceted effects that HCN channels exert on cellular excitability and neuronal network dynamics as well as their modulation by environmental factors, it has been difficult to identify the detailed mechanism by which different HCN isoforms modulate ASs. In this review, we systematically and critically analyze evidence from established AS models and normal non-epileptic animals with area- and time-selective ablation of HCN1, HCN2 and HCN4. Notably, whereas knockout of rat HCN1 and mouse HCN2 leads to the expression of ASs, the pharmacological block of all HCN channel isoforms abolishes genetically determined ASs. These seemingly contradictory results could be reconciled by taking into account the well-known opposite effects of Ih on cellular excitability and network function. Whereas existing evidence from mouse and rat AS models indicates that pan-HCN blockers may provide a novel approach for the treatment of human ASs, the development of HCN isoform-selective drugs would greatly contribute to current research on the role for these channels in ASs generation and maintenance as well as offer new potential clinical applications.
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Affiliation(s)
- Vincenzo Crunelli
- Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, UK.
| | - Francois David
- Integrative Neuroscience and Cognition Center, Paris University, Paris, France
| | - Tatiana P Morais
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, Malta University, Msida, Malta
| | - Magor L Lorincz
- Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, UK; Department of Physiology, Szeged University, Szeged, Hungary.
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Sysoeva MV, Kuznetsova GD, Sysoev IV, Ngomba RT, Vinogradova LV, Grishchenko AA, van Rijn CM, van Luijtelaar G. NETWORK ANALYSIS REVEALS A ROLE OF THE HIPPOCAMPUS IN ABSENCE SEIZURES: THE EFFECTS OF A CANNABINOID AGONIST. Epilepsy Res 2023; 192:107135. [PMID: 37023553 DOI: 10.1016/j.eplepsyres.2023.107135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/27/2023] [Accepted: 03/30/2023] [Indexed: 04/04/2023]
Abstract
The role of the hippocampus (Hp) in absence epileptic networks and the effect of endocannabinoid system on this network remain enigmatic. Here, using adapted nonlinear Granger causality, we compared the differences in network strength in four intervals (baseline or interictal, preictal, ictal and postictal) in two hours before (Epoch 1) and six hours (epochs 2, 3 and 4) after the administration of three different doses of the endocannabinoid agonist WIN55,212-2 (WIN) or solvent. Local field potentials were recorded for eight hours in 23 WAG/Rij rats in the Frontal (FC), Parietal PC), Occipital Cortex (OC) and in the hippocampus (Hp). The four intervals were visually marked by an expert neurophysiologist and the strength of couplings between electrode pairs were calculated in both directions. Ictally, a strong decrease in coupling strength was found between Hp and FC, as well as a large increase bidirectionally between PC and FC and unidirectionally from FC and PC to OC, and from FC to Hp over all epochs. The highest dose of WIN increased the couplings strength from FC to Hp and from OC to PC during 4 and 2 hr respectively in all intervals, and decreased the FC to PC coupling strength postictally in epoch 2. A single rat showed generalized convulsive seizures after the highest dose: this rat shared not only coupling changes with the other rats in the same condition, but showed many more. WIN reduced SWD number in epoch 2 and 3, their mean duration increased in epochs 3 and 4. Conclusions:during SWDs FC and PC are strongly coupled and drive OC, while at the same time the influence of Hp to FC is diminished. The first is in agreement with the cortical focus theory, the latter demonstrates an involvement of the hippocampus in SWD occurrence and that ictally the hippocampal control of the cortico-thalamo-cortical system is lost. WIN causes dramatic network changes which have major consequences for the decrease of SWDs, the occurrence of convulsive seizures, and the normal cortico-cortical and cortico-hippocampal interactions.
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Łukasiuk K, Lasoń W. Emerging Molecular Targets for Anti-Epileptogenic and Epilepsy Modifying Drugs. Int J Mol Sci 2023; 24:ijms24032928. [PMID: 36769250 PMCID: PMC9917847 DOI: 10.3390/ijms24032928] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
The pharmacological treatment of epilepsy is purely symptomatic. Despite many decades of intensive research, causal treatment of this common neurologic disorder is still unavailable. Nevertheless, it is expected that advances in modern neuroscience and molecular biology tools, as well as improved animal models may accelerate designing antiepileptogenic and epilepsy-modifying drugs. Epileptogenesis triggers a vast array of genomic, epigenomic and transcriptomic changes, which ultimately lead to morphological and functional transformation of specific neuronal circuits resulting in the occurrence of spontaneous convulsive or nonconvulsive seizures. Recent decades unraveled molecular processes and biochemical signaling pathways involved in the proepileptic transformation of brain circuits including oxidative stress, apoptosis, neuroinflammatory and neurotrophic factors. The "omics" data derived from both human and animal epileptic tissues, as well as electrophysiological, imaging and neurochemical analysis identified a plethora of possible molecular targets for drugs, which could interfere with various stages of epileptogenetic cascade, including inflammatory processes and neuroplastic changes. In this narrative review, we briefly present contemporary views on the neurobiological background of epileptogenesis and discuss the advantages and disadvantages of some more promising molecular targets for antiepileptogenic pharmacotherapy.
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Affiliation(s)
- Katarzyna Łukasiuk
- The Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Władysław Lasoń
- Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland
- Correspondence:
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Sarkisova KY, Fedosova EA, Shatskova AB, Rudenok MM, Stanishevskaya VA, Slominsky PA. Maternal Methyl-Enriched Diet Increases DNMT1, HCN1, and TH Gene Expression and Suppresses Absence Seizures and Comorbid Depression in Offspring of WAG/Rij Rats. Diagnostics (Basel) 2023; 13:diagnostics13030398. [PMID: 36766503 PMCID: PMC9914012 DOI: 10.3390/diagnostics13030398] [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: 11/13/2022] [Revised: 01/14/2023] [Accepted: 01/18/2023] [Indexed: 01/24/2023] Open
Abstract
The reduced expression of the HCN1 ion channel in the somatosensory cortex (SSC) and mesolimbic dopamine deficiency are thought to be associated with the genesis of spike-wave discharges (SWDs) and comorbid depression in the WAG/Rij rat model of absence epilepsy. This study aimed to investigate whether the maternal methyl-enriched diet (MED), which affects DNA methylation, can alter DNMT1, HCN1, and TH gene expression and modify absence seizures and comorbid depression in WAG/Rij offspring. WAG/Rij mothers were fed MED (choline, betaine, folic acid, vitamin B12, L-methionine, zinc) or a control diet for a week before mating, during pregnancy, and for a week after parturition. MED caused sustained suppression of SWDs and symptoms of comorbid depression in the offspring. Disease-modifying effects of MED were associated with increased expression of the DNMT1 and HCN1 genes in the SSC and hippocampus, as well as DNMT1, HCN1, and TH genes in the nucleus accumbens. No changes in gene expression were detected in the hypothalamus. The results indicate that maternal MED can suppress the genetic absence epilepsy and comorbid depression in offspring. Increased expression of the DNMT1, HCN1, and TH genes is suggested to be a molecular mechanism of this beneficial phenotypic effect.
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Affiliation(s)
- Karine Yu. Sarkisova
- Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova Str. 5A, Moscow 117485, Russia
- Correspondence: ; Tel.: +7-495-789-38-52 (ext. 2140); Fax: +7-499-743-00-56
| | - Ekaterina A. Fedosova
- Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova Str. 5A, Moscow 117485, Russia
| | - Alla B. Shatskova
- Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova Str. 5A, Moscow 117485, Russia
| | - Margarita M. Rudenok
- National Research Center “Kurchatov Institute”—Institute of Molecular Genetics of Russian Academy of Sciences, Kurchatov Square 2, Moscow 123182, Russia
| | - Vera A. Stanishevskaya
- National Research Center “Kurchatov Institute”—Institute of Molecular Genetics of Russian Academy of Sciences, Kurchatov Square 2, Moscow 123182, Russia
| | - Petr A. Slominsky
- National Research Center “Kurchatov Institute”—Institute of Molecular Genetics of Russian Academy of Sciences, Kurchatov Square 2, Moscow 123182, Russia
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Alpha2-Adrenergic Receptors as a Pharmacological Target for Spike-Wave Epilepsy. Int J Mol Sci 2023; 24:ijms24021477. [PMID: 36674992 PMCID: PMC9862736 DOI: 10.3390/ijms24021477] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/30/2022] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
Spike-wave discharges are the hallmark of idiopathic generalized epilepsy. They are caused by a disorder in the thalamocortical network. Commercially available anti-epileptic drugs have pronounced side effects (i.e., sedation and gastroenterological concerns), which might result from a low selectivity to molecular targets. We suggest a specific subtype of adrenergic receptors (ARs) as a promising anti-epileptic molecular target. In rats with a predisposition to absence epilepsy, alpha2 ARs agonists provoke sedation and enhance spike-wave activity during transitions from awake/sedation. A number of studies together with our own observations bring evidence that the sedative and proepileptic effects require different alpha2 ARs subtypes activation. Here we introduce a new concept on target pharmacotherapy of absence epilepsy via alpha2B ARs which are presented almost exclusively in the thalamus. We discuss HCN and calcium channels as the most relevant cellular targets of alpha2 ARs involved in spike-wave activity generation.
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Gabova AV, Sarkisova KY. Maternal Methyl-Enriched Diet Normalizes Characteristics of the Sleep–Wake Cycle and Sleep Spindles in Adult Offspring of WAG/Rij Rats with Genetic Absence Epilepsy. J EVOL BIOCHEM PHYS+ 2023. [DOI: 10.1134/s0022093023010143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
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Coulson B, Hunter I, Doran S, Parkin J, Landgraf M, Baines RA. Critical periods in Drosophila neural network development: Importance to network tuning and therapeutic potential. Front Physiol 2022; 13:1073307. [PMID: 36531164 PMCID: PMC9757492 DOI: 10.3389/fphys.2022.1073307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/23/2022] [Indexed: 02/25/2024] Open
Abstract
Critical periods are phases of heightened plasticity that occur during the development of neural networks. Beginning with pioneering work of Hubel and Wiesel, which identified a critical period for the formation of ocular dominance in mammalian visual network connectivity, critical periods have been identified for many circuits, both sensory and motor, and across phyla, suggesting a universal phenomenon. However, a key unanswered question remains why these forms of plasticity are restricted to specific developmental periods rather than being continuously present. The consequence of this temporal restriction is that activity perturbations during critical periods can have lasting and significant functional consequences for mature neural networks. From a developmental perspective, critical period plasticity might enable reproducibly robust network function to emerge from ensembles of cells, whose properties are necessarily variable and fluctuating. Critical periods also offer significant clinical opportunity. Imposed activity perturbation during these periods has shown remarkable beneficial outcomes in a range of animal models of neurological disease including epilepsy. In this review, we spotlight the recent identification of a locomotor critical period in Drosophila larva and describe how studying this model organism, because of its simplified nervous system and an almost complete wired connectome, offers an attractive prospect of understanding how activity during a critical period impacts a neuronal network.
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Affiliation(s)
- Bramwell Coulson
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Iain Hunter
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Sarah Doran
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Jill Parkin
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Matthias Landgraf
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Richard A. Baines
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
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Sarkisova K, van Luijtelaar G. The impact of early-life environment on absence epilepsy and neuropsychiatric comorbidities. IBRO Neurosci Rep 2022; 13:436-468. [PMID: 36386598 PMCID: PMC9649966 DOI: 10.1016/j.ibneur.2022.10.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/30/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022] Open
Abstract
This review discusses the long-term effects of early-life environment on epileptogenesis, epilepsy, and neuropsychiatric comorbidities with an emphasis on the absence epilepsy. The WAG/Rij rat strain is a well-validated genetic model of absence epilepsy with mild depression-like (dysthymia) comorbidity. Although pathologic phenotype in WAG/Rij rats is genetically determined, convincing evidence presented in this review suggests that the absence epilepsy and depression-like comorbidity in WAG/Rij rats may be governed by early-life events, such as prenatal drug exposure, early-life stress, neonatal maternal separation, neonatal handling, maternal care, environmental enrichment, neonatal sensory impairments, neonatal tactile stimulation, and maternal diet. The data, as presented here, indicate that some early environmental events can promote and accelerate the development of absence seizures and their neuropsychiatric comorbidities, while others may exert anti-epileptogenic and disease-modifying effects. The early environment can lead to phenotypic alterations in offspring due to epigenetic modifications of gene expression, which may have maladaptive consequences or represent a therapeutic value. Targeting DNA methylation with a maternal methyl-enriched diet during the perinatal period appears to be a new preventive epigenetic anti-absence therapy. A number of caveats related to the maternal methyl-enriched diet and prospects for future research are discussed.
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Affiliation(s)
- Karine Sarkisova
- Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova str. 5a, Moscow 117485, Russia
| | - Gilles van Luijtelaar
- Donders Institute for Brain, Cognition, and Behavior, Donders Center for Cognition, Radboud University, Nijmegen, PO Box 9104, 6500 HE Nijmegen, the Netherlands
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Knowles JK, Xu H, Soane C, Batra A, Saucedo T, Frost E, Tam LT, Fraga D, Ni L, Villar K, Talmi S, Huguenard JR, Monje M. Maladaptive myelination promotes generalized epilepsy progression. Nat Neurosci 2022; 25:596-606. [PMID: 35501379 PMCID: PMC9076538 DOI: 10.1038/s41593-022-01052-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 03/14/2022] [Indexed: 12/18/2022]
Abstract
Activity-dependent myelination can fine-tune neural network dynamics. Conversely, aberrant neuronal activity, as occurs in disorders of recurrent seizures (epilepsy), could promote maladaptive myelination, contributing to pathogenesis. In this study, we tested the hypothesis that activity-dependent myelination resulting from absence seizures, which manifest as frequent behavioral arrests with generalized electroencephalography (EEG) spike-wave discharges, promote thalamocortical network hypersynchrony and contribute to epilepsy progression. We found increased oligodendrogenesis and myelination specifically within the seizure network in two models of generalized epilepsy with absence seizures (Wag/Rij rats and Scn8a+/mut mice), evident only after epilepsy onset. Aberrant myelination was prevented by pharmacological seizure inhibition in Wag/Rij rats. Blocking activity-dependent myelination decreased seizure burden over time and reduced ictal synchrony as assessed by EEG coherence. These findings indicate that activity-dependent myelination driven by absence seizures contributes to epilepsy progression; maladaptive myelination may be pathogenic in some forms of epilepsy and other neurological diseases.
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Affiliation(s)
- Juliet K Knowles
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.
| | - Haojun Xu
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.,Ph.D. Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, Tsukuba, Japan
| | - Caroline Soane
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Ankita Batra
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Tristan Saucedo
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Eleanor Frost
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Lydia T Tam
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Danielle Fraga
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Lijun Ni
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Katlin Villar
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - Sydney Talmi
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
| | - John R Huguenard
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.
| | - Michelle Monje
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA. .,Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA.
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14
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Çarçak N, Karanfil C, Akat Ş, Akman Ö, Onat F. The effect of chronic treatment with sodium channel blocker lacosamide on early development of absence seizures in genetic absence epilepsy rats. Epilepsy Res 2022; 182:106896. [DOI: 10.1016/j.eplepsyres.2022.106896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 02/07/2022] [Accepted: 03/04/2022] [Indexed: 11/03/2022]
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15
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Effects of in utero exposure to valproate or levetiracetam on the seizures and newborn histopathology of genetic absence epilepsy rats. Neurosci Lett 2022; 776:136574. [PMID: 35271996 DOI: 10.1016/j.neulet.2022.136574] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 11/22/2022]
Abstract
Valproate (VPA) and levetiracetam (LEV), the two broad spectrum antiseizure drugs with antiabsence effects were previously tested for their antiepileptogenic effects when administered in the early postnatal period and revealed possible modification of the epileptogenic process though the effect being not persistent. The aim of this study was to investigate the effects of in utero exposure to these drugs on the absence epilepsy seizures of Genetic Absence Epilepsy Rats from Strasbourg (GAERS) rats on electroencephalogram (EEG) which are characterised by bilateral, symmetrical, and synchronized spike-and-wave discharges (SWDs). Considering LEV was proposed as a safer drug of choice in pregnancy, its effects on the newborn histopathology of GAERS was also investigated. Adult female GAERS were randomly grouped as VPA-(400 mg/kg/day), LEV- (100 mg/kg/day), and saline-treated. The drugs were injected into the animals intraperitoneally starting before pregnancy until parturition. The lungs, kidneys, and brains of the LEV-exposed newborns were evaluated histologically to be compared with unexposed naïve Wistar and GAERS newborns. Rest of the VPA-, LEV-, and saline-exposed offsprings were taken for EEG recordings on postnatal day 90. VPA or LEV did not show significant effect on mean cumulative duration and mean number of SWDs on EEG. The lungs of the LEV-exposed offsprings showed thickened alveolar epithelium in most regions, suggesting incomplete development of the alveoli. The renal examination revealed dilated Bowman's spaces in some renal corpuscles, which may be interpreted as a deleterious effect of LEV on the kidney. In addition, brain examination of LEV- and saline-exposed groups revealed irregularities in cortical thickness compared to Wistar control group. Lack of significant difference on SWD parameters may indicate that the mechanism responsible for the antiepileptogenic effects of VPA and LEV may not be operating in the prenatal period. The detrimental effect of LEV exposure observed in our study on the lungs and the kidneys of the newborns should be investigated by further studies with advanced molecular and biochemical techniques.
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16
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Fedosova EA, Shatskova AB, Sarkisova KY. Ethosuximide Improves Cognitive Flexibility during Reversal Learning in WAG/Rij Rats with Absence Epilepsy and Comorbid Depression. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022010100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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The role of thalamic nuclei in genetic generalized epilepsies. Epilepsy Res 2022; 182:106918. [DOI: 10.1016/j.eplepsyres.2022.106918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/11/2022] [Accepted: 03/28/2022] [Indexed: 01/10/2023]
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18
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Shao J, Liu Y, Gao D, Tu J, Yang F. Neural Burst Firing and Its Roles in Mental and Neurological Disorders. Front Cell Neurosci 2021; 15:741292. [PMID: 34646123 PMCID: PMC8502892 DOI: 10.3389/fncel.2021.741292] [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: 07/14/2021] [Accepted: 08/26/2021] [Indexed: 11/29/2022] Open
Abstract
Neural firing patterns are critical for specific information coding and transmission, and abnormal firing is implicated in a series of neural pathologies. Recent studies have indicated that enhanced burst firing mediated by T-type voltage-gated calcium channels (T-VGCCs) in specific neuronal subtypes is involved in several mental or neurological disorders such as depression and epilepsy, while suppression of T-VGCCs relieve related symptoms. Burst firing consists of groups of relatively high-frequency spikes separated by quiescence. Neurons in a variety of brain areas, including the thalamus, hypothalamus, cortex, and hippocampus, display burst firing, but the ionic mechanisms that generating burst firing and the related physiological functions vary among regions. In this review, we summarize recent findings on the mechanisms underlying burst firing in various brain areas, as well as the roles of burst firing in several mental and neurological disorders. We also discuss the ion channels and receptors that may regulate burst firing directly or indirectly, with these molecules highlighted as potential intervention targets for the treatment of mental and neurological disorders.
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Affiliation(s)
- Jie Shao
- The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Yunhui Liu
- The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Dashuang Gao
- The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Jie Tu
- The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Fan Yang
- The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.,Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Beijing, China
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19
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Hunter I, Coulson B, Zarin AA, Baines RA. The Drosophila Larval Locomotor Circuit Provides a Model to Understand Neural Circuit Development and Function. Front Neural Circuits 2021; 15:684969. [PMID: 34276315 PMCID: PMC8282269 DOI: 10.3389/fncir.2021.684969] [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: 03/24/2021] [Accepted: 06/09/2021] [Indexed: 11/13/2022] Open
Abstract
It is difficult to answer important questions in neuroscience, such as: "how do neural circuits generate behaviour?," because research is limited by the complexity and inaccessibility of the mammalian nervous system. Invertebrate model organisms offer simpler networks that are easier to manipulate. As a result, much of what we know about the development of neural circuits is derived from work in crustaceans, nematode worms and arguably most of all, the fruit fly, Drosophila melanogaster. This review aims to demonstrate the utility of the Drosophila larval locomotor network as a model circuit, to those who do not usually use the fly in their work. This utility is explored first by discussion of the relatively complete connectome associated with one identified interneuron of the locomotor circuit, A27h, and relating it to similar circuits in mammals. Next, it is developed by examining its application to study two important areas of neuroscience research: critical periods of development and interindividual variability in neural circuits. In summary, this article highlights the potential to use the larval locomotor network as a "generic" model circuit, to provide insight into mammalian circuit development and function.
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Affiliation(s)
- Iain Hunter
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Bramwell Coulson
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Aref Arzan Zarin
- Department of Biology, The Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, United States
| | - Richard A Baines
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
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20
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Di Cicco G, Marzano E, Iacovelli L, Celli R, van Luijtelaar G, Nicoletti F, Ngomba RT, Wall MJ. Group I metabotropic glutamate receptor-mediated long term depression is disrupted in the hippocampus of WAG/Rij rats modelling absence epilepsy. Neuropharmacology 2021; 196:108686. [PMID: 34197893 DOI: 10.1016/j.neuropharm.2021.108686] [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: 02/15/2021] [Revised: 06/16/2021] [Accepted: 06/17/2021] [Indexed: 11/19/2022]
Abstract
Absence epilepsy is frequently associated with cognitive dysfunction, although the underlying mechanisms are not well understood. Here we report that some forms of hippocampal synaptic plasticity are abnormal in symptomatic Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats. Metabotropic Glu 1/5 receptor-mediated long term depression (LTD) at Schaffer collateral CA1 synapses is significantly reduced in symptomatic, 5-6 months old WAG/Rij rats compared to age-matched non epileptic control rats. There were no significant changes in mGlu1/5-dependent LTD in pre-symptomatic, 4-6 weeks old WAG/Rij rats compared to age matched controls. The changes in LTD found in symptomatic WAG/Rij forms are not indicative of general deficits in all forms of synaptic plasticity as long term potentiation (LTP) was unchanged. Immunoblot analysis of hippocampal tissue showed a significant reduction in mGlu5 receptor expression, a trend to an increase in pan Homer protein levels and a decrease in GluA1 receptor expression in the hippocampus of symptomatic WAG/Rij rats vs non-epileptic control rats. There were no changes in mGlu1α receptor or GluA2 protein levels. These findings suggest that abnormalities in hippocampal mGlu5 receptor-dependent synaptic plasticity are associated with the pathological phenotype of WAG/Rij rats. This lays the groundwork for the study of mGlu5 receptors as a candidate drug target for the treatment of cognitive dysfunction linked to absence epilepsy.
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Affiliation(s)
- Gabriele Di Cicco
- Departments of Physiology and Pharmacology, University Sapienza of Rome, Italy
| | - Emanuela Marzano
- Departments of Physiology and Pharmacology, University Sapienza of Rome, Italy
| | - Luisa Iacovelli
- Departments of Physiology and Pharmacology, University Sapienza of Rome, Italy
| | | | | | - Ferdinando Nicoletti
- Departments of Physiology and Pharmacology, University Sapienza of Rome, Italy; IRCCS Neuromed, Pozzilli, Italy
| | - Richard T Ngomba
- University of Lincoln, School of Pharmacy Lincoln, United Kingdom; and, Coventry, UK.
| | - Mark J Wall
- School of Life Sciences, University of Warwick, Coventry, UK.
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21
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Crunelli V, Lőrincz ML, McCafferty C, Lambert RC, Leresche N, Di Giovanni G, David F. Clinical and experimental insight into pathophysiology, comorbidity and therapy of absence seizures. Brain 2020; 143:2341-2368. [PMID: 32437558 PMCID: PMC7447525 DOI: 10.1093/brain/awaa072] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/19/2019] [Accepted: 01/31/2020] [Indexed: 12/24/2022] Open
Abstract
Absence seizures in children and teenagers are generally considered relatively benign because of their non-convulsive nature and the large incidence of remittance in early adulthood. Recent studies, however, show that 30% of children with absence seizures are pharmaco-resistant and 60% are affected by severe neuropsychiatric comorbid conditions, including impairments in attention, cognition, memory and mood. In particular, attention deficits can be detected before the epilepsy diagnosis, may persist even when seizures are pharmacologically controlled and are aggravated by valproic acid monotherapy. New functional MRI-magnetoencephalography and functional MRI-EEG studies provide conclusive evidence that changes in blood oxygenation level-dependent signal amplitude and frequency in children with absence seizures can be detected in specific cortical networks at least 1 min before the start of a seizure, spike-wave discharges are not generalized at seizure onset and abnormal cortical network states remain during interictal periods. From a neurobiological perspective, recent electrical recordings and imaging of large neuronal ensembles with single-cell resolution in non-anaesthetized models show that, in contrast to the predominant opinion, cortical mechanisms, rather than an exclusively thalamic rhythmogenesis, are key in driving seizure ictogenesis and determining spike-wave frequency. Though synchronous ictal firing characterizes cortical and thalamic activity at the population level, individual cortico-thalamic and thalamocortical neurons are sparsely recruited to successive seizures and consecutive paroxysmal cycles within a seizure. New evidence strengthens previous findings on the essential role for basal ganglia networks in absence seizures, in particular the ictal increase in firing of substantia nigra GABAergic neurons. Thus, a key feature of thalamic ictogenesis is the powerful increase in the inhibition of thalamocortical neurons that originates at least from two sources, substantia nigra and thalamic reticular nucleus. This undoubtedly provides a major contribution to the ictal decrease in total firing and the ictal increase of T-type calcium channel-mediated burst firing of thalamocortical neurons, though the latter is not essential for seizure expression. Moreover, in some children and animal models with absence seizures, the ictal increase in thalamic inhibition is enhanced by the loss-of-function of the astrocytic GABA transporter GAT-1 that does not necessarily derive from a mutation in its gene. Together, these novel clinical and experimental findings bring about paradigm-shifting views of our understanding of absence seizures and demand careful choice of initial monotherapy and continuous neuropsychiatric evaluation of affected children. These issues are discussed here to focus future clinical and experimental research and help to identify novel therapeutic targets for treating both absence seizures and their comorbidities.
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Affiliation(s)
- Vincenzo Crunelli
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.,Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff, UK
| | - Magor L Lőrincz
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff, UK.,Department of Physiology, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Physiology, Anatomy and Neuroscience, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Cian McCafferty
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Régis C Lambert
- Sorbonne Université, CNRS, INSERM, Neuroscience Paris Seine and Institut de Biologie Paris Seine (NPS - IBPS), Paris, France
| | - Nathalie Leresche
- Sorbonne Université, CNRS, INSERM, Neuroscience Paris Seine and Institut de Biologie Paris Seine (NPS - IBPS), Paris, France
| | - Giuseppe Di Giovanni
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.,Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff, UK
| | - François David
- Cerebral dynamics, learning and plasticity, Integrative Neuroscience and Cognition Center - UMR 8002, Paris, France
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22
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DEMİRTAŞ ŞAHİN T, UTKAN T, KARSON A, YAZIR Y, KARAOZ E. Genetik absans epilepsili WAG/Rij sıçanlarda kardiyovasküler değişiklikler: Kronik etosüksimid tedavisinin etkileri. CUKUROVA MEDICAL JOURNAL 2020. [DOI: 10.17826/cumj.724491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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23
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Balikci A, Ilbay G, Ates N. Neonatal Tactile Stimulations Affect Genetic Generalized Epilepsy and Comorbid Depression-Like Behaviors. Front Behav Neurosci 2020; 14:132. [PMID: 32792925 PMCID: PMC7390910 DOI: 10.3389/fnbeh.2020.00132] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/02/2020] [Indexed: 12/18/2022] Open
Abstract
Recent studies suggest that development of absence epilepsy and comorbid depression might be prevented by increased maternal care of the offspring, in which tactile stimulation induced by licking/grooming and non-nutritive contact seem to be crucial. In this study, we aimed to evaluate the effect of neonatal tactile stimulations (NTS) on absence epilepsy and depression-like behaviors in adulthood. Wistar Albino Glaxo from Rijswijk (WAG/Rij) rat pups with a genetic predisposition to absence epilepsy were divided into tactile stimulation (TS) group, deep touch pressure (DTP) group, maternal separation (MS) group or control group. Between postnatal day 3 and 21, manipulations (TS, DTP, and MS) were carried out for 15 min and three times a day. Animals were submitted to locomotor activity, sucrose consumption test (SCT) and forced swimming test (FST) at five months of age. At the age of six months, the electroencephalogram (EEG) recordings were conducted in order to quantify the spike-wave discharges (SWDs), which is the hallmark of absence epilepsy. The TS and DTP groups showed less and shorter SWDs in later life in comparison to maternally separated and control rats. SWDs’ number and total duration were significantly reduced in TS and DTP groups whereas mean duration of SWDs was reduced only in DTP group (p < 0.05). TS and DTP also decreased depression-like behaviors measured by SCT and FST in adult animals. In the SCT, number of approaches was significantly higher in TS and DTP groups than the maternally separated and control rats. In the FST, while the immobility latency of TS and DTP groups was significantly higher, only TS group showed significantly decreased immobility and increased swimming time. The results showed that NTS decreases both the number and length of SWDs and the depression-like behaviors in WAG/Rij rats probably by increasing arousal level and causing alterations in the level of some neurotrophic factors as well as in functions of the neural plasticity in the developing rat’s brain.
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Affiliation(s)
- Aymen Balikci
- Department of Physiology, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey
| | - Gul Ilbay
- Department of Physiology, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey
| | - Nurbay Ates
- Department of Physiology, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey
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24
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Fukuyama K, Fukuzawa M, Shiroyama T, Okada M. Pathogenesis and pathophysiology of autosomal dominant sleep-related hypermotor epilepsy with S284L-mutant α4 subunit of nicotinic ACh receptor. Br J Pharmacol 2020; 177:2143-2162. [PMID: 31901135 PMCID: PMC7161548 DOI: 10.1111/bph.14974] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 11/30/2019] [Accepted: 12/19/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND AND PURPOSE The mechanisms causing spontaneous epileptic seizures, including carbamazepine-resistant/zonisamide -sensitive seizures and comorbidity in autosomal dominant sleep-related hypermotor epilepsy (ADSHE) are unclear. This study investigated functional abnormalities in thalamocortical transmission in transgenic rats bearing rat S286L-mutant Chrna4 (S286L-TG) of α4 subunit of the nicotinic ACh receptor (nAChR) that corresponds to the human S284L-mutant CHRNA4. EXPERIMENTAL APPROACH Effects of carbamazepine and zonisamide on epileptic discharges of S286L-TG rat were measured using telemetry electrocorticogram. Transmission abnormalities of L-glutamate and GABA in thalamocortical pathway of S286L-TG rats were investigated using multiprobe microdialysis and ultra-high-performance liquid-chromatography. KEY RESULTS Epileptic discharges in S286L-TG rats were reduced by zonisamide but not by carbamazepine, similar to that of S284L-ADSHE patients. Carbamazepine unaffected functional abnormality in transmission of S286L-TG rats. However, zonisamide was able to compensate for the attenuated S286L-mutant nAChR induced GABA release in frontal-cortex, without affecting attenuated thalamocortical glutamatergic transmission. Excitatory effects of S286L-mutant nAChR on thalamocortical transmission were attenuated compared with those of wild-type nAChR. Loss-of-function of S286L-nAChR enhanced transmission in thalamocortical motor pathway by predominantly attenuating GABAergic transmission. However, it attenuated transmission in thalamocortical cognitive pathway by reducing inhibitory GABAergic and excitatory glutamatergic transmission. CONCLUSION AND IMPLICATIONS Our results suggest that functional abnormalities of S286L-nAChR are associated with intra-frontal and thalamocortical transmission, possibly contributing to the pathogenesis of ADSHE-seizure and comorbidity of S284L-ADSHE. Selective compensation of impaired GABAergic transmission by zonisamide (but not by carbamazepine) in frontal cortex may be involved, at least partially, in carbamazepine-resistant ADSHE-seizure of S284L-ADSHE patients.
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Affiliation(s)
- Kouji Fukuyama
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of MedicineMie UniversityTsuJapan
| | - Masashi Fukuzawa
- Department of Biology, Faculty of Agriculture and Life ScienceHirosaki UniversityHirosakiJapan
| | - Takashi Shiroyama
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of MedicineMie UniversityTsuJapan
| | - Motohiro Okada
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of MedicineMie UniversityTsuJapan
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25
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van Luijtelaar G, van Oijen G. Establishing Drug Effects on Electrocorticographic Activity in a Genetic Absence Epilepsy Model: Advances and Pitfalls. Front Pharmacol 2020; 11:395. [PMID: 32351383 PMCID: PMC7175742 DOI: 10.3389/fphar.2020.00395] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/16/2020] [Indexed: 12/18/2022] Open
Abstract
The genetic rat models such as rats of the WAG/Rij strain and GAERS were developed as models for generalized genetic epilepsy and in particular for childhood absence epilepsy. These animal models were described in the eighties of the previous century and both models have, among others, face, construct and predictive validity. Both models were and are currently used as models to predict the action of antiepileptic medication and other experimental treatments, to elucidate neurobiological mechanisms of spike-wave discharges and epileptogenesis. Although the electroencephalagram (EEG)/electrocorticogram (ECoG) is imperative for establishing absence seizures and to quantify the for absence epilepsy typical spike-wave discharges, monitoring the animals behavior is equally necessary. Here an overview is given regarding the design of drug evaluation studies, which animals to use, classical and new EEG variables, the monitoring and quantification of the behavior of the rats, some pitfalls regarding the interpretation of the data, and some developments in EEG technology.
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Affiliation(s)
| | - Gerard van Oijen
- Donders Centre for Cognition, Radboud University, Nijmegen, Netherlands
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26
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Cassano V, Leo A, Tallarico M, Nesci V, Cimellaro A, Fiorentino TV, Citraro R, Hribal ML, De Sarro G, Perticone F, Sesti G, Russo E, Sciacqua A. Metabolic and Cognitive Effects of Ranolazine in Type 2 Diabetes Mellitus: Data from an in vivo Model. Nutrients 2020; 12:nu12020382. [PMID: 32023991 PMCID: PMC7071286 DOI: 10.3390/nu12020382] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/23/2020] [Accepted: 01/28/2020] [Indexed: 02/06/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a risk factor for cognitive impairment. Ranolazine, an anti-ischemic drug used in the treatment of angina pectoris, has been shown to possess hypoglycemic properties in pre-clinical and clinical studies. The aim of this study was to evaluate the effects of ranolazine on glucose metabolism and cognitive function in a T2DM model of Wistar rats. Diabetes was induced by a high fat diet (HFD) and streptozotocin (STZ). The control group received a normal caloric diet (NCD) and sodium citrate buffer. Metformin, an effective hypoglycemic drug, was employed as a positive control. Animals were divided into the following groups: HFD/STZ + Ranolazine, HFD/STZ + Metformin, HFD/STZ + Vehicle, NCD + Vehicle, NCD + Ranolazine, and NCD + Metformin. Rats received ranolazine (20 mg/kg), metformin (300 mg/kg), or water, for 8 weeks. At the end of the treatments, all animals underwent to an intraperitoneal glucose tolerance test (IPGTT) and behavioral tests, including passive avoidance, novel object recognition, forced swimming, and elevate plus maze tests. Interleukin-6 plasma levels in the six treatment groups were assessed by Elisa assay. Body mass composition was estimated by nuclear magnetic resonance (NMR). Glucose responsiveness significantly improved in the HFD/STZ + Ranolazine (p < 0.0001) and HFD/STZ + Metformin (p = 0.003) groups. There was a moderate effect on blood glucose levels in the NCD + Ranolazine and NCD + Metformin groups. Lean body mass was significantly increased in the HFD/STZ + Ranolazine and HFD/STZ + Metformin animals, compared to HFD/STZ + Vehicle animals. Ranolazine improved learning and long-term memory in HFD/STZ + Ranolazine compared to HFD/STZ + Vehicle (p < 0.001) and ameliorated the pro-inflammatory profile of diabetic mice. These results support the hypothesis of a protective effect of ranolazine against cognitive decline caused by T2DM.
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Affiliation(s)
- Velia Cassano
- Department of Medical and Surgical Sciences, Magna Græcia University, 88100 Catanzaro, Italy
| | - Antonio Leo
- Science of Health Department, Magna Græcia University, 88100 Catanzaro, Italy (V.N.)
| | - Martina Tallarico
- Science of Health Department, Magna Græcia University, 88100 Catanzaro, Italy (V.N.)
| | - Valentina Nesci
- Science of Health Department, Magna Græcia University, 88100 Catanzaro, Italy (V.N.)
| | - Antonio Cimellaro
- Pugliese-Ciaccio, Hospital, Internal Medicine Unit, 88100 Catanzaro, Italy
| | | | - Rita Citraro
- Science of Health Department, Magna Græcia University, 88100 Catanzaro, Italy (V.N.)
| | - Marta Letizia Hribal
- Department of Medical and Surgical Sciences, Magna Græcia University, 88100 Catanzaro, Italy
- Correspondence: ; Tel.: +39-0961-364-7411
| | | | - Francesco Perticone
- Department of Medical and Surgical Sciences, Magna Græcia University, 88100 Catanzaro, Italy
| | - Giorgio Sesti
- Department of Clinical and Molecular Medicine, University of Rome-Sapienza, 00189 Rome, Italy
| | - Emilio Russo
- Science of Health Department, Magna Græcia University, 88100 Catanzaro, Italy (V.N.)
| | - Angela Sciacqua
- Department of Medical and Surgical Sciences, Magna Græcia University, 88100 Catanzaro, Italy
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Gawel K, Turski WA, van der Ent W, Mathai BJ, Kirstein-Smardzewska KJ, Simonsen A, Esguerra CV. Phenotypic Characterization of Larval Zebrafish (Danio rerio) with Partial Knockdown of the cacna1a Gene. Mol Neurobiol 2019; 57:1904-1916. [PMID: 31875924 PMCID: PMC7118054 DOI: 10.1007/s12035-019-01860-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 12/15/2019] [Indexed: 12/18/2022]
Abstract
The CACNA1A gene encodes the pore-forming α1 subunit of voltage-gated P/Q type Ca2+ channels (Cav2.1). Mutations in this gene, among others, have been described in patients and rodents suffering from absence seizures and episodic ataxia type 2 with/without concomitant seizures. In this study, we aimed for the first time to assess phenotypic and behavioral alterations in larval zebrafish with partial cacna1aa knockdown, placing special emphasis on changes in epileptiform-like electrographic discharges in larval brains. Whole-mount in situ hybridization analysis revealed expression of cacna1aa in the optic tectum and medulla oblongata of larval zebrafish at 4 and 5 days post-fertilization. Next, microinjection of two antisense morpholino oligomers (individually or in combination) targeting all splice variants of cacna1aa into fertilized zebrafish eggs resulted in dose-dependent mortality and decreased or absent touch response. Over 90% knockdown of cacna1aa on protein level induced epileptiform-like discharges in the optic tectum of larval zebrafish brains. Incubation of morphants with antiseizure drugs (sodium valproate, ethosuximide, lamotrigine, topiramate) significantly decreased the number and, in some cases, cumulative duration of epileptiform-like discharges. In this context, sodium valproate seemed to be the least effective. Carbamazepine did not affect the number and duration of epileptiform-like discharges. Altogether, our data indicate that cacna1aa loss-of-function zebrafish may be considered a new model of absence epilepsy and may prove useful both for the investigation of Cacna1a-mediated epileptogenesis and for in vivo drug screening.
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Affiliation(s)
- Kinga Gawel
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway.,Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | - Waldemar A Turski
- Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | - Wietske van der Ent
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Benan J Mathai
- Faculty of Medicine, Institute of Basic Medical Sciences and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, 1112 Blindern, 0317, Oslo, Norway
| | - Karolina J Kirstein-Smardzewska
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Anne Simonsen
- Faculty of Medicine, Institute of Basic Medical Sciences and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, 1112 Blindern, 0317, Oslo, Norway
| | - Camila V Esguerra
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway. .,School of Pharmacy, Faculty of Mathematics and Natural Sciences, University of Oslo, Sem Sælandsvei 24, 0371, Oslo, Norway.
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Modifying genetic epilepsies - Results from studies on tuberous sclerosis complex. Neuropharmacology 2019; 166:107908. [PMID: 31962286 DOI: 10.1016/j.neuropharm.2019.107908] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Revised: 12/03/2019] [Accepted: 12/05/2019] [Indexed: 12/12/2022]
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous disorder affecting approximately 1 in 6,000 in general population and represents one of the most common genetic causes of epilepsy. Epilepsy affects 90% of the patients and appears in the first 2 years of life in the majority of them. Early onset of epilepsy in the first year of life is associated with high risk of cognitive decline and neuropsychiatric problems including autism. Recently TSC has been recognized as a model of genetic epilepsies. TSC is a genetic condition with known dysregulated mTOR pathway and is increasingly viewed as a model for human epileptogenesis. Moreover, TSC is characterized by a hyperactivation of mTOR (mammalian target of rapamycin) pathway, and mTOR activation was showed to be implicated in epileptogenesis in many animal models and human epilepsies. Recently published studies documented positive effect of preventive or disease modifying treatment of epilepsy in infants with high risk of epilepsy with significantly lower incidence of epilepsy and better cognitive outcome. Further studies on preventive treatment of epilepsy in other genetic epilepsies of early childhood are considered. 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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Leo A, Caro CD, Nesci V, Palma E, Tallarico M, Iannone M, Constanti A, Sarro GD, Russo E, Citraro R. Antiepileptogenic effects of Ethosuximide and Levetiracetam in WAG/Rij rats are only temporary. Pharmacol Rep 2019; 71:833-838. [PMID: 31386986 DOI: 10.1016/j.pharep.2019.04.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 03/22/2019] [Accepted: 04/23/2019] [Indexed: 11/08/2022]
Abstract
BACKGROUND WAG/Rij rats represent a validated genetic animal model of epileptogenesis, absence epilepsy and depressive-like comorbidity. Some treatments (e.g. ethosuximide), using specific protocols, prevent the development of spontaneous absence seizures. Accordingly, ethosuximide increases remission occurrence in children with childhood absence epilepsy in comparison to valproic acid. Considering that in this animal model, antiepileptogenic effects are, in some cases, not retained over time, we studied whether the antiepileptogenic effects of both ethosuximide and levetiracetam (which also possesses antiepileptogenic effects in this and other animal epilepsy models) would be retained 5 months after drug suspension. METHODS WAG/Rij rats of ˜1 month of age were treated long-term with one of the two drugs at a dose of ˜80 mg/kg/day for 17 consecutive weeks; 1 and 5 months after drug suspension, the development of absence seizures as well as depressive-like behaviour were assessed by EEG recordings and the forced swimming test (FST). RESULTS In agreement with a previous report, both drugs continued to show antiepileptogenic effects 1 month after their discontinuation. Furthermore, ethosuximide improved depressive-like behaviour, whereas in contrast, levetiracetam worsened this symptom. However, none of the drugs maintained their antiepileptogenic effects 5 months after suspension, and in addition, animal behaviour in the FST returned to control conditions. CONCLUSION Overall, these results demonstrate that the antiepileptogenic effects of both ethosuximide and levetiracetam on absence seizure development and associated depressive-like behaviour in this model are only temporary.
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Affiliation(s)
- Antonio Leo
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy
| | - Carmen De Caro
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy
| | - Valentina Nesci
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy
| | - Ernesto Palma
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy
| | - Martina Tallarico
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy; CNR, Institute of Neurological Sciences, Pharmacology Section, Roccelletta di Borgia, Catanzaro, Italy
| | - Michelangelo Iannone
- CNR, Institute of Neurological Sciences, Pharmacology Section, Roccelletta di Borgia, Catanzaro, Italy
| | | | | | - Emilio Russo
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy
| | - Rita Citraro
- University of Catanzaro, School of Medicine, Science of Health Department, Catanzaro, Italy.
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Klein P, Tyrlikova I. No prevention or cure of epilepsy as yet. Neuropharmacology 2019; 168:107762. [PMID: 31499048 DOI: 10.1016/j.neuropharm.2019.107762] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/02/2019] [Accepted: 09/05/2019] [Indexed: 12/29/2022]
Abstract
Approximately 20% of all epilepsy is caused by acute acquired injury such as traumatic brain injury, stroke and CNS infection. The known onset of the injury which triggers the epileptogenic process, early presentation to medical care, and a latency between the injury and the development of clinical epilepsy present an opportunity to intervene with treatment to prevent epilepsy. No such treatment exists and yet there has been remarkably little clinical research during the last 20 years to try to develop such treatment. We review possible reasons for this, possible ways to rectify the situations and note some of the ways currently under way to do so. Resective surgical treatment can achieve "cure" in some patients but is sparsely utilized. In certain "self-limiting" syndromes of childhood and adolescence epilepsy remits spontaneously. In a proportion of patients who become seizure free on medications or with dietary treatment, seizure freedom persists when treatment is discontinued. We discuss these situations which can be considered "cures"; and note that at present we have little understanding of mechanism of such cures, and cannot therefore translate them into a treatment paradigm targeting a "cure" of epilepsy. 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)
- Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, MD, USA.
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31
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Leo A, Citraro R, Tallarico M, Iannone M, Fedosova E, Nesci V, De Sarro G, Sarkisova K, Russo E. Cognitive impairment in the WAG/Rij rat absence model is secondary to absence seizures and depressive-like behavior. Prog Neuropsychopharmacol Biol Psychiatry 2019; 94:109652. [PMID: 31095993 DOI: 10.1016/j.pnpbp.2019.109652] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 04/30/2019] [Accepted: 05/12/2019] [Indexed: 01/06/2023]
Abstract
Neuropsychiatric comorbidities are common in patients with epilepsy, remaining still an urgent unmet clinical need. Therefore, the management of epileptic disorders should not only be restricted to the achievement of seizure-freedom but must also be able to counteract its related comorbidities. Experimental animal models of epilepsy represent a valid tool not only to study epilepsy but also its associated comorbidities. The WAG/Rij rat is a well-established genetically-based model of absence epilepsy with depressive-like comorbidity, in which learning and memory impairment was also recently reported. Aim of this study was to clarify whether this cognitive decline is secondary or not to absence seizures and/or depressive-like behavior. The behavioral performance of untreated and ethosuximide-treated (300 mg/kg/day; 17 days) WAG/Rij rats at 6 and 12 months of age were assessed in several tests: forced swimming test, objects recognition test, social recognition test, Morris water maze and passive avoidance. According to our results, it seems that cognitive impairment in this strain, similarly to depressive-like behavior, is secondary to the occurrence of absence seizures, which might be necessary for the expression of cognitive impairment. Furthermore, our results suggest an age-dependent impairment of cognitive performance in WAG/Rij rats, which could be linked to the age-dependent increase of spike wave discharges. Consistently, it is possible that absence seizures, depressive-like behavior and cognitive deficit may arise independently and separately in lifetime from the same underlying network disease, as previously suggested for the behavioral features associated with other epileptic syndromes.
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Affiliation(s)
- Antonio Leo
- University of Catanzaro, School of Medicine, Science of Health Dept., Catanzaro, Italy
| | - Rita Citraro
- University of Catanzaro, School of Medicine, Science of Health Dept., Catanzaro, Italy.
| | - Martina Tallarico
- University of Catanzaro, School of Medicine, Science of Health Dept., Catanzaro, Italy; CNR, Institute of Neurological Sciences, Pharmacology Section, Roccelletta di Borgia, Catanzaro, Italy
| | - Michelangelo Iannone
- CNR, Institute of Neurological Sciences, Pharmacology Section, Roccelletta di Borgia, Catanzaro, Italy
| | - Ekaterina Fedosova
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, Russia
| | - Valentina Nesci
- University of Catanzaro, School of Medicine, Science of Health Dept., Catanzaro, Italy
| | | | - Karine Sarkisova
- Institute of Higher Nervous Activity and Neurophysiology RAS, Moscow, Russia
| | - Emilio Russo
- University of Catanzaro, School of Medicine, Science of Health Dept., Catanzaro, Italy
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Yu Y, Nguyen DT, Jiang J. G protein-coupled receptors in acquired epilepsy: Druggability and translatability. Prog Neurobiol 2019; 183:101682. [PMID: 31454545 DOI: 10.1016/j.pneurobio.2019.101682] [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: 05/29/2019] [Revised: 07/09/2019] [Accepted: 08/15/2019] [Indexed: 02/06/2023]
Abstract
As the largest family of membrane proteins in the human genome, G protein-coupled receptors (GPCRs) constitute the targets of more than one-third of all modern medicinal drugs. In the central nervous system (CNS), widely distributed GPCRs in neuronal and nonneuronal cells mediate numerous essential physiological functions via regulating neurotransmission at the synapses. Whereas their abnormalities in expression and activity are involved in various neuropathological processes. CNS conditions thus remain highly represented among the indications of GPCR-targeted agents. Mounting evidence from a large number of animal studies suggests that GPCRs play important roles in the regulation of neuronal excitability associated with epilepsy, a common CNS disease afflicting approximately 1-2% of the population. Surprisingly, none of the US Food and Drug Administration (FDA)-approved (>30) antiepileptic drugs (AEDs) suppresses seizures through acting on GPCRs. This disparity raises concerns about the translatability of these preclinical findings and the druggability of GPCRs for seizure disorders. The currently available AEDs intervene seizures predominantly through targeting ion channels and have considerable limitations, as they often cause unbearable adverse effects, fail to control seizures in over 30% of patients, and merely provide symptomatic relief. Thus, identifying novel molecular targets for epilepsy is highly desired. Herein, we focus on recent progresses in understanding the comprehensive roles of several GPCR families in seizure generation and development of acquired epilepsy. We also dissect current hurdles hindering translational efforts in developing GPCRs as antiepileptic and/or antiepileptogenic targets and discuss the counteracting strategies that might lead to a potential cure for this debilitating CNS condition.
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Affiliation(s)
- Ying Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Davis T Nguyen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jianxiong Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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Kobylarek D, Iwanowski P, Lewandowska Z, Limphaibool N, Szafranek S, Labrzycka A, Kozubski W. Advances in the Potential Biomarkers of Epilepsy. Front Neurol 2019; 10:685. [PMID: 31312171 PMCID: PMC6614180 DOI: 10.3389/fneur.2019.00685] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 06/12/2019] [Indexed: 12/11/2022] Open
Abstract
Epilepsy is a group of chronic neurological disorders characterized by recurrent, spontaneous, and unpredictable seizures. It is one of the most common neurological disorders, affecting tens of millions of people worldwide. Comprehensive studies on epilepsy in recent decades have revealed the complexity of epileptogenesis, in which immunological processes, epigenetic modifications, and structural changes in neuronal tissues have been identified as playing a crucial role. This review discusses the recent advances in the biomarkers of epilepsy. We evaluate the possible molecular background underlying the clinical changes observed in recent studies, focusing on therapeutic investigations, and the evidence of their safety and efficacy in the human population. This article reviews the pathophysiology of epilepsy, including recent reports on the effects of oxidative stress and hypoxia, and focuses on specific biomarkers and their clinical implications, along with further perspectives in epilepsy research.
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Affiliation(s)
- Dominik Kobylarek
- Department of Neurology, Poznan University of Medical Sciences, Poznan, Poland
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The effects of lamotrigine and ethosuximide on seizure frequency, neuronal loss, and astrogliosis in a model of temporal-lobe epilepsy. Brain Res 2019; 1712:1-6. [DOI: 10.1016/j.brainres.2019.01.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 01/18/2019] [Accepted: 01/26/2019] [Indexed: 12/28/2022]
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Zobeiri M, Chaudhary R, Blaich A, Rottmann M, Herrmann S, Meuth P, Bista P, Kanyshkova T, Lüttjohann A, Narayanan V, Hundehege P, Meuth SG, Romanelli MN, Urbano FJ, Pape HC, Budde T, Ludwig A. The Hyperpolarization-Activated HCN4 Channel is Important for Proper Maintenance of Oscillatory Activity in the Thalamocortical System. Cereb Cortex 2019; 29:2291-2304. [PMID: 30877792 PMCID: PMC6458902 DOI: 10.1093/cercor/bhz047] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 02/15/2019] [Accepted: 02/21/2019] [Indexed: 11/14/2022] Open
Abstract
Hyperpolarization-activated cation channels are involved, among other functions, in learning and memory, control of synaptic transmission and epileptogenesis. The importance of the HCN1 and HCN2 isoforms for brain function has been demonstrated, while the role of HCN4, the third major neuronal HCN subunit, is not known. Here we show that HCN4 is essential for oscillatory activity in the thalamocortical (TC) network. HCN4 is selectively expressed in various thalamic nuclei, excluding the thalamic reticular nucleus. HCN4-deficient TC neurons revealed a massive reduction of Ih and strongly reduced intrinsic burst firing, whereas the current was normal in cortical pyramidal neurons. In addition, evoked bursting in a thalamic slice preparation was strongly reduced in the mutant mice probes. HCN4-deficiency also significantly slowed down thalamic and cortical oscillations during active wakefulness. Taken together, these results establish that thalamic HCN4 channels are essential for the production of rhythmic intrathalamic oscillations and determine regular TC oscillatory activity during alert states.
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Affiliation(s)
- Mehrnoush Zobeiri
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Rahul Chaudhary
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Anne Blaich
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Matthias Rottmann
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Stefan Herrmann
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Patrick Meuth
- Klinik für Neurologie mit Institut für Translationale Neurologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - Pawan Bista
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Tatyana Kanyshkova
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Annika Lüttjohann
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Venu Narayanan
- Klinik für Neurologie mit Institut für Translationale Neurologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - Petra Hundehege
- Klinik für Neurologie mit Institut für Translationale Neurologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - Sven G Meuth
- Klinik für Neurologie mit Institut für Translationale Neurologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - Maria Novella Romanelli
- Department of Neurosciences, Psychology, Drug Research and Child Health, University of Florence, Via Ugo Schiff 6, Sesto Fiorentino, Italy
| | | | - Hans-Christian Pape
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Thomas Budde
- Institut für Physiologie I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Andreas Ludwig
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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Martínez-Ferrández C, Martínez-Salcedo E, Casas-Fernández C, Alarcón-Martínez H, Ibáñez-Micó S, Domingo-Jiménez R. Long-term prognosis of childhood absence epilepsy. NEUROLOGÍA (ENGLISH EDITION) 2019. [DOI: 10.1016/j.nrleng.2016.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Löscher W. The holy grail of epilepsy prevention: Preclinical approaches to antiepileptogenic treatments. Neuropharmacology 2019; 167:107605. [PMID: 30980836 DOI: 10.1016/j.neuropharm.2019.04.011] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/03/2019] [Accepted: 04/09/2019] [Indexed: 02/06/2023]
Abstract
A variety of acute brain insults can induce epileptogenesis, a complex process that results in acquired epilepsy. Despite advances in understanding mechanisms of epileptogenesis, there is currently no approved treatment that prevents the development or progression of epilepsy in patients at risk. The current concept of epileptogenesis assumes a window of opportunity following acute brain insults that allows intervention with preventive treatment. Recent results suggest that injury-induced epileptogenesis can be a much more rapid process than previously thought, suggesting that the 'therapeutic window' may only be open for a brief period, as in stroke therapy. However, experimental data also suggest a second, possibly delayed process ("secondary epileptogenesis") that influences the progression and refractoriness of the epileptic state over time, allowing interfering with this process even after onset of epilepsy. In this review, both methodological issues in preclinical drug development and novel targets for antiepileptogenesis will be discussed. Several promising drugs that either prevent epilepsy (antiepileptogenesis) or slow epilepsy progression and alleviate cognitive or behavioral comorbidities of epilepsy (disease modification) have been described in recent years, using diverse animal models of acquired epilepsy. Promising agents include TrkB inhibitors, losartan, statins, isoflurane, anti-inflammatory and anti-oxidative drugs, the SV2A modulator levetiracetam, and epigenetic interventions. Research on translational target validity and on prognostic biomarkers that can be used to stratify patients (or experimental animals) at high risk of developing epilepsy will hopefully soon lead to proof-of-concept clinical trials with the most promising drugs, which will be essential to make prevention of epilepsy a reality. 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)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
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Saletti PG, Ali I, Casillas-Espinosa PM, Semple BD, Lisgaras CP, Moshé SL, Galanopoulou AS. In search of antiepileptogenic treatments for post-traumatic epilepsy. Neurobiol Dis 2019; 123:86-99. [PMID: 29936231 PMCID: PMC6309524 DOI: 10.1016/j.nbd.2018.06.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 06/20/2018] [Indexed: 11/28/2022] Open
Abstract
Post-traumatic epilepsy (PTE) is diagnosed in 20% of individuals with acquired epilepsy, and can impact significantly the quality of life due to the seizures and other functional or cognitive and behavioral outcomes of the traumatic brain injury (TBI) and PTE. There is no available antiepileptogenic or disease modifying treatment for PTE. Animal models of TBI and PTE have been developed, offering useful insights on the value of inflammatory, neurodegenerative pathways, hemorrhages and iron accumulation, calcium channels and other target pathways that could be used for treatment development. Most of the existing preclinical studies test efficacy towards pathologies of functional recovery after TBI, while a few studies are emerging testing the effects towards induced or spontaneous seizures. Here we review the existing preclinical trials testing new candidate treatments for TBI sequelae and PTE, and discuss future directions for efforts aiming at developing antiepileptogenic and disease-modifying treatments.
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Affiliation(s)
- Patricia G Saletti
- Saul R. Korey Department of Neurology, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Idrish Ali
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne, Australia; Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, Australia
| | - Pablo M Casillas-Espinosa
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne, Australia; Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, Australia
| | - Bridgette D Semple
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne, Australia; Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, Australia
| | - Christos Panagiotis Lisgaras
- Saul R. Korey Department of Neurology, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Solomon L Moshé
- Saul R. Korey Department of Neurology, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, USA; Dominick P. Purpura Department of Neuroscience, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Einstein/Montefiore Epilepsy Center, Montefiore Medical Center, Bronx, NY, USA; Department of Pediatrics, Albert Einstein College of Medicine, Einstein/Montefiore Epilepsy Center, Montefiore Medical Center, Bronx, NY, USA
| | - Aristea S Galanopoulou
- Saul R. Korey Department of Neurology, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Bronx, NY, USA; Dominick P. Purpura Department of Neuroscience, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine, Einstein/Montefiore Epilepsy Center, Montefiore Medical Center, Bronx, NY, USA.
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Morse E, Giblin K, Chung MH, Dohle C, Berg AT, Blumenfeld H. Historical trend toward improved long-term outcome in childhood absence epilepsy. Epilepsy Res 2019; 152:7-10. [PMID: 30856420 DOI: 10.1016/j.eplepsyres.2019.02.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/19/2019] [Accepted: 02/25/2019] [Indexed: 01/21/2023]
Abstract
We retrospectively analyzed published studies to investigate historical trends in outcome of childhood absence epilepsy (CAE). We included patients based on onset of absence seizures in childhood, 3 Hz bilateral spike-wave discharges on EEG, and availability of seizure-free outcome data. The primary endpoint was seizure-freedom off medications by study publication year. We also analyzed relationships between seizure-freedom and 1. treatment medication, and 2. CAE diagnostic criteria. We included 29 studies published 1945-2013, encompassing 2416 patients. Seizure-freedom off medications was higher for studies after 1985 versus before 1975 (82% versus 35%; p < 0.001). Ethosuximide and valproate were used more commonly after 1985, and patients previously treated with ethosuximide or valproate had higher seizure-freedom off medications than those treated only with other medications (64% versus 32%; χ2>10; p < 0.001). Although differences in diagnostic criteria for early vs. later studies did not reach statistical significance, later studies tended to use normal EEG background (p = 0.09) and absence of comorbid disorders (p = 0.09) as criteria more commonly. These findings demonstrate that seizure-freedom off medications has improved in published CAE studies after 1985. Our results are limited due to retrospective analysis. Further work is needed with prospective, controlled trials to establish factors leading to improved long-term prognosis in CAE.
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Affiliation(s)
- Elliot Morse
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA
| | - Kathryn Giblin
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA
| | - Mi Hae Chung
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA
| | - Carolin Dohle
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA
| | - Anne T Berg
- Department of Pediatric Neurology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
| | - Hal Blumenfeld
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA; Department of Neuroscience, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA; Department of Neurosurgery, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut, 06520, USA.
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Halász P, Bódizs R, Ujma PP, Fabó D, Szűcs A. Strong relationship between NREM sleep, epilepsy and plastic functions - A conceptual review on the neurophysiology background. Epilepsy Res 2019; 150:95-105. [PMID: 30712997 DOI: 10.1016/j.eplepsyres.2018.11.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 10/08/2018] [Accepted: 11/15/2018] [Indexed: 12/15/2022]
Abstract
The aim of this review is to summarize and discuss the strong bond between NREM sleep and epilepsy underlain by the shared link and effect on brain plasticity. Beyond the seizure occurrence rate, sleep relatedness may manifest in the enhancement of interictal epileptic discharges (spikes and pathological ripples). The number of the discharges as well as their propagation increase during NREM sleep, unmasking the epileptic network that is hidden during wakefulness. The interictal epileptic discharges associate with different sleep constituents (sleep slow waves, spindling and high frequency oscillations); known to play essential role in memory and learning. We highlight three major groups of epilepsies, in which sleep-related plastic functions suffer an epileptic derailment. In absence epilepsy mainly involving the thalamo-cortical system, sleep spindles transform to generalized spike-wave activity. In mesio-temporal epilepsy affecting the hippocampal declarative memory system, the sharp wave ripples derail to dysfunctional epileptic oscillations (spikes and pathological ripples). Idiopathic childhood epilepsies affecting the perisylvian network may progress to catastrophic status electricus during NREM sleep. In these major epilepsies, NREM sleep has a pivotal role in the development and course of the disorder. Epilepsy is born in-, and exhibits its pathological properties during NREM sleep. Interictal discharges are important causative agents in this process.
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Affiliation(s)
- Péter Halász
- National Institute of Clinical Neuroscience, Amerikai út 57. Budapest, H-1145, Hungary.
| | - Róbert Bódizs
- Semmelweis University, Institute of Behavioral Sciences, Nagyvárad tér 4, Budapest, H-1089, Hungary
| | - Péter Przemyslaw Ujma
- Semmelweis University, Institute of Behavioral Sciences, Nagyvárad tér 4, Budapest, H-1089, Hungary
| | - Dániel Fabó
- National Institute of Clinical Neuroscience, Amerikai út 57. Budapest, H-1145, Hungary
| | - Anna Szűcs
- National Institute of Clinical Neuroscience, Amerikai út 57. Budapest, H-1145, Hungary
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Pawluski JL, Kuchenbuch M, Hadjadj S, Dieuset G, Costet N, Vercueil L, Biraben A, Martin B. Long-term negative impact of an inappropriate first antiepileptic medication on the efficacy of a second antiepileptic medication in mice. Epilepsia 2018; 59:e109-e113. [PMID: 29901235 DOI: 10.1111/epi.14454] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2018] [Indexed: 11/29/2022]
Abstract
Childhood absence epilepsy (CAE) is one of the most frequent epilepsies in infancy. The first-line recommended therapy for CAE is based on the prescription of the narrow-spectrum ethosuximide and the broad-spectrum valproic acid, which have similar efficacy in the first 12 months. Nevertheless, some antiepileptic drugs (AEDs) may worsen seizure duration and type in this syndrome. In line with this, we have encountered a case of identical twins with CAE and early exposure to different antiseizure drugs leading to divergent outcomes. From this, we hypothesized that the first AED to treat CAE may determine the long-term prognosis, especially in the developing brain, and that some situations leading to drug resistance may be explained by use of an inappropriate first AED. Therefore, we investigated this hypothesis by using a genetic mouse model of absence epilepsy (BS/Orl). Mice received a first appropriate or inappropriate AED followed by the same appropriate AED. Our data demonstrate that an inappropriate first AED has a negative impact on the long-term efficacy of a second appropriate AED. This work supports the necessity to effectively diagnose epileptic syndromes prior to medication use, particularly in children, in order to prevent the deleterious effects of an inappropriate initial AED.
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Affiliation(s)
- Jodi L Pawluski
- Univ Rennes, Inserm, EHESP, Irset (Research Institute for Environmental and Occupational Health), UMR_S 1085, Rennes, France
| | | | - Sarah Hadjadj
- Univ Rennes, CHU Rennes, INSERM, LTSI - UMR 1099, Rennes, France
| | - Gabriel Dieuset
- Univ Rennes, CHU Rennes, INSERM, LTSI - UMR 1099, Rennes, France
| | - Nathalie Costet
- Univ Rennes, CHU Rennes, INSERM, LTSI - UMR 1099, Rennes, France
| | - Laurent Vercueil
- Inserm, GIN, University of Grenoble Alpes, Grenoble, France.,EFSN, CHU Grenoble Alpes, Grenoble, France
| | - Arnaud Biraben
- Univ Rennes, CHU Rennes, INSERM, LTSI - UMR 1099, Rennes, France
| | - Benoît Martin
- Univ Rennes, CHU Rennes, INSERM, LTSI - UMR 1099, Rennes, France
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Russo E, Citraro R. Pharmacology of epileptogenesis and related comorbidities in the WAG/Rij rat model of genetic absence epilepsy. J Neurosci Methods 2018; 310:54-62. [PMID: 29857008 DOI: 10.1016/j.jneumeth.2018.05.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/25/2018] [Accepted: 05/28/2018] [Indexed: 01/23/2023]
Abstract
Animal studies currently represent the best source of information also in the field of epileptogenesis research. Many animal models have been proposed and studied so far both from the pathophysiological and pharmacological point of view. Furthermore, they are widely used for the identification of potentially clinically valuable biomarkers. The WAG/Rij rat model, similarly to other genetic animal strains, represents a suitable animal model of absence epileptogenesis accompanied by depressive-like and cognitive comorbidities. Generally, animal models of epileptogenesis are characterized by an identifiable initial insult (e.g. traumatic brain injury), a latent phase lasting up to the appearance of the first spontaneous seizure and a chronic phase characterized by recurrent spontaneous seizures. In most of genetic models: the initial insult should be defined as the mutation causing epilepsy, which is not clearly defined in the WAG/Rij rat model; the latent phase ends at the appearance of the first spontaneous seizure, which is about 2-3 months of age in WAG/Rij rats and thereafter the chronic phase. WAG/Rij rats also display depressive-like comorbidity around the age of 4 months, which is apparently linked to the development of absence seizures considering both its ontogeny and the fact that drugs affecting absence seizures development also block the development of depressive-like behavior. Finally, WAG/Rij rats also display cognitive impairment in some memory tasks, however, this has not been yet definitively linked to absence seizures development and may represent an epiphenomenon. This review is focused on the effects of pharmacological treatments against epileptogenesis and their effects on comorbidities.
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Affiliation(s)
- Emilio Russo
- Science of Health Department, School of Medicine, University of Catanzaro, Italy.
| | - Rita Citraro
- Science of Health Department, School of Medicine, University of Catanzaro, Italy
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Sarkisova KY, Gabova AV. Maternal care exerts disease-modifying effects on genetic absence epilepsy and comorbid depression. GENES BRAIN AND BEHAVIOR 2018; 17:e12477. [DOI: 10.1111/gbb.12477] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/27/2018] [Accepted: 03/28/2018] [Indexed: 12/31/2022]
Affiliation(s)
- K. Y. Sarkisova
- Institute of Higher Nervous Activity and Neurophysiology Russian Academy of Sciences; Moscow Russia
| | - A. V. Gabova
- Institute of Higher Nervous Activity and Neurophysiology Russian Academy of Sciences; Moscow Russia
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45
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Reid CA, Rollo B, Petrou S, Berkovic SF. Can mutation‐mediated effects occurring early in development cause long‐term seizure susceptibility in genetic generalized epilepsies? Epilepsia 2018; 59:915-922. [DOI: 10.1111/epi.14077] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Christopher Alan Reid
- The Florey Institute for Neuroscience and Mental Health The University of Melbourne Parkville Victoria Australia
| | - Ben Rollo
- The Florey Institute for Neuroscience and Mental Health The University of Melbourne Parkville Victoria Australia
| | - Steven Petrou
- The Florey Institute for Neuroscience and Mental Health The University of Melbourne Parkville Victoria Australia
| | - Samuel F. Berkovic
- Department of Medicine Epilepsy Research Centre Austin Health University of Melbourne Heidelberg Victoria Australia
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Leo A, Citraro R, Amodio N, De Sarro C, Gallo Cantafio ME, Constanti A, De Sarro G, Russo E. Fingolimod Exerts only Temporary Antiepileptogenic Effects but Longer-Lasting Positive Effects on Behavior in the WAG/Rij Rat Absence Epilepsy Model. Neurotherapeutics 2017; 14:1134-1147. [PMID: 28653281 PMCID: PMC5722759 DOI: 10.1007/s13311-017-0550-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
One of the major challenges in the epilepsy field is identifying disease-modifying drugs in order to prevent or delay spontaneous recurrent seizure onset or to cure already established epilepsy. It has been recently reported that fingolimod, currently approved for the treatment of relapsing-remitting multiple sclerosis, has demonstrated antiepileptogenic effects in 2 different preclinical models of acquired epilepsy. However, to date, no data exist regarding the role of fingolimod against genetic epilepsy. Therefore, we have addressed this issue by studying the effects of fingolimod in Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats, a well-established genetic model of absence epilepsy, epileptogenesis, and neuropsychiatric comorbidity. Our results have demonstrated that an early long-term treatment with fingolimod (1 mg/kg/day), started before absence seizure onset, has both antiepileptogenic and antidepressant-like effects in WAG/Rij rats. However, these effects were transitory, as 5 months after treatment discontinuation, both absence seizure and depressive like-behavior returned to control levels. Furthermore, a temporary reduction of mTOR signaling pathway activity, indicated by reduced phosphorylated mammalian target of rapamycin and phosphorylated p70S6k levels, and by increased phosphorylated Akt in WAG/Rij rats of 6 months of age accompanied the transitory antiepileptogenic effects of fingolimod. Surprisingly, fingolimod has demonstrated longer-lasting positive effects on cognitive decline in this strain. This effect was accompanied by an increased acetylation of lysine 8 of histone H4 (at both 6 and 10 months of age). In conclusion, our results support the antiepileptogenic effects of fingolimod. However, the antiepileptogenic effects were transitory. Moreover, fingolimod might also have a positive impact on animal behavior and particularly in protecting the development of memory decline.
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Affiliation(s)
- Antonio Leo
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Rita Citraro
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Nicola Amodio
- Department of Experimental and Clinical Medicine, Magna Graecia University and Translational Medical Oncology Unit, Salvatore Venuta University Campus, Catanzaro, Italy
| | - Caterina De Sarro
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Maria Eugenia Gallo Cantafio
- Department of Experimental and Clinical Medicine, Magna Graecia University and Translational Medical Oncology Unit, Salvatore Venuta University Campus, Catanzaro, Italy
| | | | - Giovambattista De Sarro
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Emilio Russo
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Catanzaro, Italy.
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47
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Velioglu SK, Gedikli O, Yıldırım M, Ayar A. Epilepsy may cause increased pain sensitivity: Evidence from absence epileptic WAG/Rij rats. Epilepsy Behav 2017; 75:146-150. [PMID: 28866333 DOI: 10.1016/j.yebeh.2017.07.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 07/05/2017] [Accepted: 07/05/2017] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The comorbidity of epilepsy and pain disorders as well as effectiveness of certain therapeutic approaches in both conditions attracted attention to epilepsy-pain interactions. This lead to the discovery of significantly shared pathophysiological mechanisms although many aspects remain largely unknown. To test the hypothesis that epilepsy may be associated with altered pain sensitivity, we analyzed interictal pain sensitivity using epilepsy prone WAG/Rij rats, a genetic model exhibiting age-related-onset absence epilepsy. METHODS Two series of experiments were conducted. In experiment I, pain sensitivity of symptomatic WAG/Rij rats were compared with age-matched control Wistar rats. In experiment II, pain sensitivity of WAG/Rij rats were monitored longitudinally when they were presymptomatic (at 2months) and symptomatic (after maturation, at 8months), and compared with age-matched control Wistar rats. Pain sensitivity was assessed by applying heat stimuli to hind paws and measuring the paw-withdrawal latency using thermal plantar analgesia meter in awake and freely moving animals. All pain measurements were made during the interictal period, confirmed by simultaneous electroencephalography through intracranially implanted electrodes. RESULTS In experiment I, the interictal pain withdrawal latency of symptomatic WAG/Rij rats was significantly shorter than control Wistar rats (P<0.01). In experiment II, WAG/Rij rats had significantly shorter latency of withdrawal response than control Wistar rats, both at presymptomatic (P<0.05) and symptomatic stage (P<0.0001). Matured (8months old) control Wistar rats demonstrated significantly increased withdrawal latency compared to the 2months animals (P<0.01), but the WAG/Rij rats did not (P>0.5). CONCLUSION Epileptic WAG/Rij rats present significantly increased pain sensitivity when compared to control Wistar rats, suggesting comorbidity of epilepsy and pain.
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Affiliation(s)
- Sibel K Velioglu
- Karadeniz Technical University, Faculty of Medicine, Neurology Department, Clinical Neurophysiology Unit, Trabzon, Turkey.
| | - Oznur Gedikli
- Karadeniz Technical University, Faculty of Medicine, Physiology Department, Trabzon, Turkey
| | - Mehmet Yıldırım
- University of Health Sciences, Faculty of Medicine, Medical Physiology Department, Istanbul, Turkey
| | - Ahmet Ayar
- Karadeniz Technical University, Faculty of Medicine, Physiology Department, Trabzon, Turkey
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Jarre G, Altwegg-Boussac T, Williams MS, Studer F, Chipaux M, David O, Charpier S, Depaulis A, Mahon S, Guillemain I. Building Up Absence Seizures in the Somatosensory Cortex: From Network to Cellular Epileptogenic Processes. Cereb Cortex 2017; 27:4607-4623. [DOI: 10.1093/cercor/bhx174] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 06/22/2017] [Indexed: 01/14/2023] Open
Affiliation(s)
- Guillaume Jarre
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
- Inserm, U1216, F-38000 Grenoble, France
| | - Tristan Altwegg-Boussac
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Mark S. Williams
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Florian Studer
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
- Inserm, U1216, F-38000 Grenoble, France
| | - Mathilde Chipaux
- Pediatric Neurosurgery Department, Fondation Ophtalmologique A. de Rothschild, 75019 Paris, France
| | - Olivier David
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
- Inserm, U1216, F-38000 Grenoble, France
- CHU de Grenoble, F-38000 Grenoble, France
| | - Stéphane Charpier
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
- UPMC Univ Paris 06, F-75005, Paris, France
| | - Antoine Depaulis
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
- Inserm, U1216, F-38000 Grenoble, France
- CHU de Grenoble, F-38000 Grenoble, France
| | - Séverine Mahon
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Isabelle Guillemain
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
- Inserm, U1216, F-38000 Grenoble, France
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Clossen BL, Reddy DS. Novel therapeutic approaches for disease-modification of epileptogenesis for curing epilepsy. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1519-1538. [PMID: 28179120 PMCID: PMC5474195 DOI: 10.1016/j.bbadis.2017.02.003] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/31/2017] [Accepted: 02/03/2017] [Indexed: 11/16/2022]
Abstract
This article describes the recent advances in epileptogenesis and novel therapeutic approaches for the prevention of epilepsy, with a special emphasis on the pharmacological basis of disease-modification of epileptogenesis for curing epilepsy. Here we assess animal studies and human clinical trials of epilepsy spanning 1982-2016. Epilepsy arises from a number of neuronal factors that trigger epileptogenesis, which is the process by which a brain shifts from a normal physiologic state to an epileptic condition. The events precipitating these changes can be of diverse origin, including traumatic brain injury, cerebrovascular damage, infections, chemical neurotoxicity, and emergency seizure conditions such as status epilepticus. Expectedly, the molecular and system mechanisms responsible for epileptogenesis are not well defined or understood. To date, there is no approved therapy for the prevention of epilepsy. Epigenetic dysregulation, neuroinflammation, and neurodegeneration appear to trigger epileptogenesis. Targeted drugs are being identified that can truly prevent the development of epilepsy in at-risk people. The promising agents include rapamycin, COX-2 inhibitors, TRK inhibitors, epigenetic modulators, JAK-STAT inhibitors, and neurosteroids. Recent evidence suggests that neurosteroids may play a role in modulating epileptogenesis. A number of promising drugs are under investigation for the prevention or modification of epileptogenesis to halt the development of epilepsy. Some drugs in development appear rational for preventing epilepsy because they target the initial trigger or related signaling pathways as the brain becomes progressively more prone to seizures. Additional research into the target validity and clinical investigation is essential to make new frontiers in curing epilepsy.
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Affiliation(s)
- Bryan L Clossen
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX 77807, USA
| | - Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX 77807, USA.
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50
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Martínez-Ferrández C, Martínez-Salcedo E, Casas-Fernández C, Alarcón-Martínez H, Ibáñez-Micó S, Domingo-Jiménez R. Long-term prognosis of childhood absence epilepsy. Neurologia 2017; 34:224-228. [PMID: 28325560 DOI: 10.1016/j.nrl.2016.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 12/19/2016] [Accepted: 12/20/2016] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Childhood absence epilepsy (CAE) is considered easily manageable with medication provided that a strict patient classification system is employed. It accounts for 10% of all childhood epilepsy cases starting before the age of 15 and it is most frequent in school-aged girls. The aim of this study is to analyse long-term outcomes of patients diagnosed with CAE according to the Loiseau and Panayiotopoulos criteria and treated during childhood. METHODS We conducted a retrospective study including 69 patients with CAE who are currently older than 11; data were gathered from medical histories, EEG records, and telephone questionnaires. RESULTS 52 patients met the Loiseau and Panayiotopoulos criteria. Mean age is now 17.16 years. Female-to-male ratio was 1.65:1; mean age at onset was 6 years and 2 months; mean duration of treatment was 3 years and 9 months. A family history of epilepsy was present in 30.8% of the patients and 7.7% had a personal history of febrile convulsions. Absence seizures were simple in 73.5% of the patients and complex in 26.5%. Response rates to first-line treatment were as follows: valproic acid, 46.3%; and valproic acid plus ethosuximide, 90.9%. The rate of response to second-line therapy (ethosuximide or lamotrigine) was 84.2%; 4% of the patients experienced further seizures after treatment discontinuation, 78.8% achieved seizure remission, and 25% needed psychological and academic support. CONCLUSIONS Our data show that epileptic patients should be classified according to strict diagnostic criteria since patients with true CAE have an excellent prognosis. The relapse rate was very low in our sample. Despite the favourable prognosis, psychological and academic support is usually necessary.
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Affiliation(s)
- C Martínez-Ferrández
- Sección Neuropediatría, Pediatría, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España.
| | - E Martínez-Salcedo
- Sección Neuropediatría, Pediatría, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - C Casas-Fernández
- Sección Neuropediatría, Pediatría, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - H Alarcón-Martínez
- Sección Neuropediatría, Pediatría, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - S Ibáñez-Micó
- Sección Neuropediatría, Pediatría, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - R Domingo-Jiménez
- Sección Neuropediatría, Pediatría, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
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