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Ergul Erkec O, Yunusoglu O, Huyut Z. Evaluation of repeated ghrelin administration on seizures, oxidative stress and neurochemical parameters in pentyleneterazole induced kindling in rats. Int J Neurosci 2024; 134:420-428. [PMID: 35903909 DOI: 10.1080/00207454.2022.2107516] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 10/16/2022]
Abstract
Introduction: Epileptic seizures are thought to be caused by the impaired balance between excitatory (glutamate) and inhibitor [gamma amino butyric acid (GABA)] neurotransmitters in the brain. Neuropeptides have potent modulator properties on these neurotransmitters.Objective: Ghrelin exerts anticonvulsant effects in an acute pentylenetetrazole (PTZ) model. However, the effect of repeated ghrelin injections in chronic pentylenetetrazole kindling model is not known. In this study, the effects of repeated ghrelin administration on seizure scores, working memory, locomotor activity, oxidative biomarkers, and neurochemical parameters in PTZ kindling in rats was examined.Methods: For this purpose, 35 mg/kg of PTZ was administered intraperitoneally to the experimental groups. The rats also received physiological saline/diazepam or ghrelin before each PTZ injection. After behavioural analysis (Y-maze, rotarod, and locomotor activity tests), biochemical and neurochemical analyses were conducted using ELISA.Results: PTZ administration induced progression in the seizure scores and all of the rats in the PS + PTZ group were kindled with the 20th injection. Ghrelin treatment significantly reduced the seizure scores. The difference among the groups in terms of the Y-maze, locomotor activity, and rotarod tests was nonsignificant. PTZ administration significantly decreased the brain GABA, CAT, and AChE levels, and increased the MDA, NO, and protein carbonyl levels. Repeated ghrelin treatment ameliorated the GABA, AChE, CAT, MDA, NO, and protein carbonyl levels.Conclusion: Taken together, the results indicated that repeated ghrelin treatment had antioxidant, and anticonvulsant activity on PTZ kindling in rats.
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Affiliation(s)
- Ozlem Ergul Erkec
- Department of Physiology, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
| | - Oruc Yunusoglu
- Department of Pharmacology, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
| | - Zubeyir Huyut
- Department of Biochemistry, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
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2
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Löscher W, White HS. Animal Models of Drug-Resistant Epilepsy as Tools for Deciphering the Cellular and Molecular Mechanisms of Pharmacoresistance and Discovering More Effective Treatments. Cells 2023; 12:cells12091233. [PMID: 37174633 PMCID: PMC10177106 DOI: 10.3390/cells12091233] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/28/2023] [Accepted: 04/18/2023] [Indexed: 05/15/2023] Open
Abstract
In the last 30 years, over 20 new anti-seizure medicines (ASMs) have been introduced into the market for the treatment of epilepsy using well-established preclinical seizure and epilepsy models. Despite this success, approximately 20-30% of patients with epilepsy have drug-resistant epilepsy (DRE). The current approach to ASM discovery for DRE relies largely on drug testing in various preclinical model systems that display varying degrees of ASM drug resistance. In recent years, attempts have been made to include more etiologically relevant models in the preclinical evaluation of a new investigational drug. Such models have played an important role in advancing a greater understanding of DRE at a mechanistic level and for hypothesis testing as new experimental evidence becomes available. This review provides a critical discussion of the pharmacology of models of adult focal epilepsy that allow for the selection of ASM responders and nonresponders and those models that display a pharmacoresistance per se to two or more ASMs. In addition, the pharmacology of animal models of major genetic epilepsies is discussed. Importantly, in addition to testing chemical compounds, several of the models discussed here can be used to evaluate other potential therapies for epilepsy such as neurostimulation, dietary treatments, gene therapy, or cell transplantation. This review also discusses the challenges associated with identifying novel therapies in the absence of a greater understanding of the mechanisms that contribute to DRE. Finally, this review discusses the lessons learned from the profile of the recently approved highly efficacious and broad-spectrum ASM cenobamate.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany
- Center for Systems Neuroscience, 30559 Hannover, Germany
| | - H Steve White
- Department of Pharmacy, School of Pharmacy, University of Washington, Seattle, WA 98195, USA
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3
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Charalambous M, Fischer A, Potschka H, Walker MC, Raedt R, Vonck K, Boon P, Lohi H, Löscher W, Worrell G, Leeb T, McEvoy A, Striano P, Kluger G, Galanopoulou AS, Volk HA, Bhatti SFM. Translational veterinary epilepsy: A win-win situation for human and veterinary neurology. Vet J 2023; 293:105956. [PMID: 36791876 DOI: 10.1016/j.tvjl.2023.105956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023]
Abstract
Epilepsy is a challenging multifactorial disorder with a complex genetic background. Our current understanding of the pathophysiology and treatment of epilepsy has substantially increased due to animal model studies, including canine studies, but additional basic and clinical research is required. Drug-resistant epilepsy is an important problem in both dogs and humans, since seizure freedom is not achieved with the available antiseizure medications. The evaluation and exploration of pharmacological and particularly non-pharmacological therapeutic options need to remain a priority in epilepsy research. Combined efforts and sharing knowledge and expertise between human medical and veterinary neurologists are important for improving the treatment outcomes or even curing epilepsy in dogs. Such interactions could offer an exciting approach to translate the knowledge gained from people and rodents to dogs and vice versa. In this article, a panel of experts discusses the similarities and knowledge gaps in human and animal epileptology, with the aim of establishing a common framework and the basis for future translational epilepsy research.
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Affiliation(s)
- Marios Charalambous
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover 30559, Germany.
| | - Andrea Fischer
- Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich 80539, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University, Munich 80539, Germany
| | - Matthew C Walker
- Institute of Neurology, University College London, London WC1N 3JD, UK
| | - Robrecht Raedt
- Department of Neurology, 4brain, Ghent University, Ghent 9000, Belgium
| | - Kristl Vonck
- Department of Neurology, 4brain, Ghent University, Ghent 9000, Belgium
| | - Paul Boon
- Department of Neurology, 4brain, Ghent University, Ghent 9000, Belgium
| | - Hannes Lohi
- Department of Veterinary Biosciences, Department of Medical and Clinical Genetics, and Folkhälsan Research Center, University of Helsinki, Helsinki 00014, Finland
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover 30559, Germany
| | | | - Tosso Leeb
- Institute of Genetics, University of Bern, Bern 3001, Switzerland
| | - Andrew McEvoy
- Institute of Neurology, University College London, London WC1N 3JD, UK
| | - Pasquale Striano
- IRCCS 'G. Gaslini', Genova 16147, Italy; Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
| | - Gerhard Kluger
- Research Institute, Rehabilitation, Transition-Palliation', PMU Salzburg, Salzburg 5020, Austria; Clinic for Neuropediatrics and Neurorehabilitation, Epilepsy Center for Children and Adolescents, Schoen Clinic Vogtareuth, Vogtareuth 83569, Germany
| | - Aristea S Galanopoulou
- Saul R Korey Department of Neurology, Isabelle Rapin Division of Child Neurology, Dominick P. Purpura Department of Neuroscience, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Holger A Volk
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover 30559, Germany
| | - Sofie F M Bhatti
- Faculty of Veterinary Medicine, Small Animal Department, Ghent University, Merelbeke 9820, Belgium
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4
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Löscher W. Dogs as a Natural Animal Model of Epilepsy. Front Vet Sci 2022; 9:928009. [PMID: 35812852 PMCID: PMC9257283 DOI: 10.3389/fvets.2022.928009] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/18/2022] [Indexed: 12/13/2022] Open
Abstract
Epilepsy is a common neurological disease in both humans and domestic dogs, making dogs an ideal translational model of epilepsy. In both species, epilepsy is a complex brain disease characterized by an enduring predisposition to generate spontaneous recurrent epileptic seizures. Furthermore, as in humans, status epilepticus is one of the more common neurological emergencies in dogs with epilepsy. In both species, epilepsy is not a single disease but a group of disorders characterized by a broad array of clinical signs, age of onset, and underlying causes. Brain imaging suggests that the limbic system, including the hippocampus and cingulate gyrus, is often affected in canine epilepsy, which could explain the high incidence of comorbid behavioral problems such as anxiety and cognitive alterations. Resistance to antiseizure medications is a significant problem in both canine and human epilepsy, so dogs can be used to study mechanisms of drug resistance and develop novel therapeutic strategies to benefit both species. Importantly, dogs are large enough to accommodate intracranial EEG and responsive neurostimulation devices designed for humans. Studies in epileptic dogs with such devices have reported ictal and interictal events that are remarkably similar to those occurring in human epilepsy. Continuous (24/7) EEG recordings in a select group of epileptic dogs for >1 year have provided a rich dataset of unprecedented length for studying seizure periodicities and developing new methods for seizure forecasting. The data presented in this review substantiate that canine epilepsy is an excellent translational model for several facets of epilepsy research. Furthermore, several techniques of inducing seizures in laboratory dogs are discussed as related to therapeutic advances. Importantly, the development of vagus nerve stimulation as a novel therapy for drug-resistant epilepsy in people was based on a series of studies in dogs with induced seizures. Dogs with naturally occurring or induced seizures provide excellent large-animal models to bridge the translational gap between rodents and humans in the development of novel therapies. Furthermore, because the dog is not only a preclinical species for human medicine but also a potential patient and pet, research on this species serves both veterinary and human medicine.
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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
- *Correspondence: Wolfgang Löscher
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5
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Ding M, Lang Y, Shu H, Shao J, Cui L. Microbiota-Gut-Brain Axis and Epilepsy: A Review on Mechanisms and Potential Therapeutics. Front Immunol 2021; 12:742449. [PMID: 34707612 PMCID: PMC8542678 DOI: 10.3389/fimmu.2021.742449] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/17/2021] [Indexed: 12/16/2022] Open
Abstract
The gut-brain axis refers to the bidirectional communication between the gut and brain, and regulates intestinal homeostasis and the central nervous system via neural networks and neuroendocrine, immune, and inflammatory pathways. The development of sequencing technology has evidenced the key regulatory role of the gut microbiota in several neurological disorders, including Parkinson's disease, Alzheimer's disease, and multiple sclerosis. Epilepsy is a complex disease with multiple risk factors that affect more than 50 million people worldwide; nearly 30% of patients with epilepsy cannot be controlled with drugs. Interestingly, patients with inflammatory bowel disease are more susceptible to epilepsy, and a ketogenic diet is an effective treatment for patients with intractable epilepsy. Based on these clinical facts, the role of the microbiome and the gut-brain axis in epilepsy cannot be ignored. In this review, we discuss the relationship between the gut microbiota and epilepsy, summarize the possible pathogenic mechanisms of epilepsy from the perspective of the microbiota gut-brain axis, and discuss novel therapies targeting the gut microbiota. A better understanding of the role of the microbiota in the gut-brain axis, especially the intestinal one, would help investigate the mechanism, diagnosis, prognosis evaluation, and treatment of intractable epilepsy.
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Affiliation(s)
| | | | | | | | - Li Cui
- Department of Neurology, First Hospital of Jilin University, Changchun, China
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6
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Wu J, Wang L, Huang Y, Wu Q, Luo X, Li Y, Ren S, Wu G. Cognitive Impairment and Mossy Fiber Sprouting in a Rat Model of Drug-Resistant Epilepsy Induced by Lithium-Pilocarpine. Curr Neurovasc Res 2021; 18:374-380. [PMID: 34538230 DOI: 10.2174/1567202618666210917155408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 07/23/2021] [Accepted: 07/25/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND The mossy fiber sprouting (MFS) in the dentate gyrus is a common pathological change of epilepsy. Previous studies suggested that it is associated with drug-resistant epilepsy, and mossy cells control spontaneous seizures and spatial memory. METHODS We investigated the correlations among cognitive impairment, MFS, seizure frequency and drug resistance in a rat model of epilepsy induced by lithium-pilocarpine. Phenytoin and phenobarbital were used to screen drug resistance. Cognitive function and MFS were detected through the novel object recognition (NOR) test, Morris water maze (MWM) test and Timm staining. RESULTS The results showed that object memory and spatial memory functions were both significantly impaired in rats with epilepsy, and only spatial memory impairment was more severe in rats with drug-resistant epilepsy. More frequent spontaneous seizures and more obvious MFS were observed in the drug-resistant rats. The seizure frequency was significantly associated with the MWM performance but not with the NOR performance in rats with epilepsy. The degree of MFS was significantly associated with seizure frequency and spatial memory function. CONCLUSION Taken together, these correlations among drug resistance, seizure frequency, spatial memory impairment and MFS suggested the possibility of a common pathological mechanism. More studies are needed to clarify the underlying mechanism behind these correlations and the detailed role of MFS in epilepsy. The mechanism of mossy cell change may be an important target for the treatment of seizures, drug resistance and cognitive dysfunction in patients with epilepsy.
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Affiliation(s)
- Jing Wu
- School of Basic Medical Sciences, Guizhou Medical University, Guiyang. China
| | - Likun Wang
- Department of Emergency, Affiliated Hospital of Guizhou Medical University, Guiyang. China
| | - Yuanxin Huang
- Department of Emergency, Affiliated Hospital of Guizhou Medical University, Guiyang. China
| | - Qian Wu
- School of Clinical Medicine, Guizhou Medical University, Guiyang. China
| | - Xingmei Luo
- Department of Emergency, Affiliated Hospital of Guizhou Medical University, Guiyang. China
| | - Yinghui Li
- School of Basic Medical Sciences, Guizhou Medical University, Guiyang. China
| | - Siying Ren
- Department of Emergency, Affiliated Hospital of Guizhou Medical University, Guiyang. China
| | - Guofeng Wu
- Department of Emergency, Affiliated Hospital of Guizhou Medical University, Guiyang. China
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7
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Tynes VV, Landsberg GM. Nutritional Management of Behavior and Brain Disorders in Dogs and Cats. Vet Clin North Am Small Anim Pract 2021; 51:711-727. [PMID: 33773649 DOI: 10.1016/j.cvsm.2021.01.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
There are several natural products and functional ingredients that, either alone or in combination with other ingredients, have shown evidence for decreasing signs associated with cognitive dysfunction and anxiety in dogs and cats, and in management of seizures in dogs with epilepsy. The evidence supporting the role that a healthy gastrointestinal tract plays in behavior is also growing as more is learned about the gut-brain axis. Nutritional support may play an important role in therapy for certain brain disorders and behavioral problems, in conjunction with other aspects of management. A multimodal approach provides the greatest likelihood of success.
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Affiliation(s)
- Valarie V Tynes
- Ceva Animal Health, LLC 8735 Rosehill Road, Suite 300 Lenexa, KS 66215, USA.
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8
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Fei F, Wang X, Wang Y, Chen Z. Dissecting the role of subiculum in epilepsy: Research update and translational potential. Prog Neurobiol 2021; 201:102029. [PMID: 33636224 DOI: 10.1016/j.pneurobio.2021.102029] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 01/12/2021] [Accepted: 02/21/2021] [Indexed: 11/25/2022]
Abstract
The subiculum serves as the strategic core output of the hippocampus, through which neural activity exits the hippocampal proper and targets the entorhinal cortex and other more distant subcortical and cortical areas. The past decade has witnessed a growing interest in the subiculum, owing to discoveries revealing its critical role in regulating many physiological and pathophysiological processes. Notably, accumulating evidence from both clinical and experimental studies suggests that the subiculum plays a vital role in seizure initiation and propagation, in epilepsy. In this review, we briefly describe the structure and connectivity of the subiculum and then summarize the molecular and cellular mechanisms in the subiculum underlying the epileptic brain, in both epilepsy patients and animal models. Next, we review some translational approaches targeting the malfunctioned subiculum to treat epilepsy. Finally, we pose open questions for future research in the subiculum and their clinical translation challenges.
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Affiliation(s)
- Fan Fei
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Xia Wang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Yi Wang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China; Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhong Chen
- Institute of Pharmacology & Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China; Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China; Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
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9
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Kim SG, Lee JS. Multiscale pore contained carbon nanofiber-based field-effect transistor biosensors for nesfatin-1 detection. J Mater Chem B 2021; 9:6076-6083. [PMID: 34286811 DOI: 10.1039/d1tb00582k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nesfatin-1 (NES1) is a potential biomarker found in serum and saliva that indicates hyperpolarization and depolarization in the hypothalamic ventricle nucleus as well as an increase in epileptic conditions. However, real-time investigations have not been carried out to detect changes in the concentration of NES1. In this study, we develop a multiscale pore contained carbon nanofiber-based field-effect transistor (FET) biosensor to detect NES1. The activated multiscale pore contained carbon nanofiber (a-MPCNF) is generated using a single-nozzle co-electrospinning method and a subsequent steam-activation process to obtain a signal transducer and template for immobilization of bioreceptors. The prepared biosensor exhibits a high sensitivity to NES1. It can detect levels as low as 0.1 fM of NES1, even in the presence of other interfering biomolecules. Furthermore, the a-MPCNF-based FET sensor has significant potential for practical applications in non-invasive real-time diagnosis, as indicated by its sensing performance in artificial saliva.
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Affiliation(s)
- Sung Gun Kim
- Samsung Electronics, San #16 Banwol-Dong, Hwasung, Gyeonggi-Do18448, South Korea
| | - Jun Seop Lee
- Department of Materials Science and Engineering, Gachon University, 1342 Seongnam-Daero, Sujeong-Gu, Seongnam-Si, Gyeonggi-Do 13120, Republic of Korea.
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Löscher W, Potschka H, Sisodiya SM, Vezzani A. Drug Resistance in Epilepsy: Clinical Impact, Potential Mechanisms, and New Innovative Treatment Options. Pharmacol Rev 2020; 72:606-638. [PMID: 32540959 PMCID: PMC7300324 DOI: 10.1124/pr.120.019539] [Citation(s) in RCA: 334] [Impact Index Per Article: 83.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Epilepsy is a chronic neurologic disorder that affects over 70 million people worldwide. Despite the availability of over 20 antiseizure drugs (ASDs) for symptomatic treatment of epileptic seizures, about one-third of patients with epilepsy have seizures refractory to pharmacotherapy. Patients with such drug-resistant epilepsy (DRE) have increased risks of premature death, injuries, psychosocial dysfunction, and a reduced quality of life, so development of more effective therapies is an urgent clinical need. However, the various types of epilepsy and seizures and the complex temporal patterns of refractoriness complicate the issue. Furthermore, the underlying mechanisms of DRE are not fully understood, though recent work has begun to shape our understanding more clearly. Experimental models of DRE offer opportunities to discover, characterize, and challenge putative mechanisms of drug resistance. Furthermore, such preclinical models are important in developing therapies that may overcome drug resistance. Here, we will review the current understanding of the molecular, genetic, and structural mechanisms of ASD resistance and discuss how to overcome this problem. Encouragingly, better elucidation of the pathophysiological mechanisms underpinning epilepsies and drug resistance by concerted preclinical and clinical efforts have recently enabled a revised approach to the development of more promising therapies, including numerous potential etiology-specific drugs (“precision medicine”) for severe pediatric (monogenetic) epilepsies and novel multitargeted ASDs for acquired partial epilepsies, suggesting that the long hoped-for breakthrough in therapy for as-yet ASD-resistant patients is a feasible goal.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany (W.L.); Center for Systems Neuroscience, Hannover, Germany (W.L.); Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University, Munich, Germany (H.P.); Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom (S.S); and Department of Neuroscience, Mario Negri Institute for Pharmacological Research Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Italy (A.V.)
| | - Heidrun Potschka
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany (W.L.); Center for Systems Neuroscience, Hannover, Germany (W.L.); Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University, Munich, Germany (H.P.); Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom (S.S); and Department of Neuroscience, Mario Negri Institute for Pharmacological Research Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Italy (A.V.)
| | - Sanjay M Sisodiya
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany (W.L.); Center for Systems Neuroscience, Hannover, Germany (W.L.); Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University, Munich, Germany (H.P.); Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom (S.S); and Department of Neuroscience, Mario Negri Institute for Pharmacological Research Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Italy (A.V.)
| | - Annamaria Vezzani
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany (W.L.); Center for Systems Neuroscience, Hannover, Germany (W.L.); Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University, Munich, Germany (H.P.); Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom (S.S); and Department of Neuroscience, Mario Negri Institute for Pharmacological Research Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Italy (A.V.)
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Olszewska A, Schmidt MJ, Failing K, Nicpoń J, Podgórski P, Wrzosek MA. Interictal Single-Voxel Proton Magnetic Resonance Spectroscopy of the Temporal Lobe in Dogs With Idiopathic Epilepsy. Front Vet Sci 2020; 7:644. [PMID: 33195502 PMCID: PMC7541947 DOI: 10.3389/fvets.2020.00644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/10/2020] [Indexed: 11/16/2022] Open
Abstract
Proton magnetic resonance spectroscopy (H1-MRS) could provide insight into the metabolic pathophysiology of the temporal lobe of canine brain after seizure. Currently, there is no evidence-based data available on MRS of temporal lobe in dogs with idiopathic epilepsy (IE). The aim of this prospective, cross-sectional study was to evaluate the interictal metabolic activity of the temporal lobe in IE dogs compared to a control group with the use of H1-MRS. Ten healthy dogs and 27 client-owned dogs with IE underwent 1.5-Tesla magnetic resonance imaging (MRI) and single-voxel H1-MRS. The MRS studies were acquired as spin echoes with a repetition time (TR) of 2,000 ms and an echo time (TE) of 144 ms. A cubic voxel (10 ×10 ×10 mm) was positioned bilaterally into the region of the left and right temporal lobe, including a middle part of the hippocampus and the amygdala. The N-acetylaspartate (NAA)-to-creatine (NAA/Cr), NAA-to-choline (NAA/Cho), choline-to-creatine (Cho/Cr), and choline-to-NAA (Cho/NAA) ratios were determined in both hemispheres and compared to controls. No significant differences in all metabolite ratios between epileptic dogs and the control group could be found. A time-dependent decrease in the NAA/Cho ratio as well as an increase in the Cho/NAA ratio was found with proximity in time to the last seizure. We found no correlation between metabolite ratios and age or sex in this animal group. Time span from the last seizure to the acquisition of MRS significantly correlated with NAA/Cho and Cho/NAA ratio. We conclude that without a time relation, metabolite ratios in dogs with IE do not differ from those of the control group.
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Affiliation(s)
- Agnieszka Olszewska
- Department of Veterinary Clinical Science, Small Animal Clinic, Justus-Liebig-University Giessen, Giessen, Germany
| | - Martin Jürgen Schmidt
- Department of Veterinary Clinical Science, Small Animal Clinic, Justus-Liebig-University Giessen, Giessen, Germany
| | - Klaus Failing
- Unit for Biomathematics and Data Processing, Faculty of Veterinary Medicine, Justus Liebig-University Giessen, Giessen, Germany
| | - Józef Nicpoń
- Department of Internal Diseases With a Clinic for Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Wrocław, Poland.,Center of Experimental Diagnostics and Innovative Biomedical Technologies, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Przemysław Podgórski
- Department of General Radiology and Interventional Radiology and Neuroradiology, Wrocław Medical University, Wrocław, Poland
| | - Marcin Adam Wrzosek
- Department of Internal Diseases With a Clinic for Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
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12
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Ahmed Juvale II, Che Has AT. The evolution of the pilocarpine animal model of status epilepticus. Heliyon 2020; 6:e04557. [PMID: 32775726 PMCID: PMC7393986 DOI: 10.1016/j.heliyon.2020.e04557] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/05/2020] [Accepted: 07/22/2020] [Indexed: 02/02/2023] Open
Abstract
The pilocarpine animal model of status epilepticus is a well-established, clinically translatable model that satisfies all of the criteria essential for an animal model of status epilepticus: a latency period followed by spontaneous recurrent seizures, replication of behavioural, electrographic, metabolic, and neuropathological changes, as well as, pharmacoresistance to anti-epileptic drugs similar to that observed in human status epilepticus. However, this model is also characterized by high mortality rates and studies in recent years have also seen difficulties in seizure induction due to pilocarpine resistant animals. This can be attributed to differences in rodent strains, species, gender, and the presence of the multi-transporter, P-glycoprotein at the blood brain barrier. The current paper highlights the various alterations made to the original pilocarpine model over the years to combat both the high mortality and low induction rates. These range from the initial lithium-pilocarpine model to the more recent Reduced Intensity Status Epilepticus (RISE) model, which finally brought the mortality rates down to 1%. These modifications are essential to improve animal welfare and future experimental outcomes.
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Affiliation(s)
- Iman Imtiyaz Ahmed Juvale
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Ahmad Tarmizi Che Has
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia
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Huang Y, Wang L, Ren S, Wu G, Wu J. The Expression of ZnT3 and GFAP Is Potentiated in the Hippocampus of Drug-Resistant Epileptic Rats Induced by Amygdala Kindling. Neuroimmunomodulation 2020; 27:104-112. [PMID: 33161399 DOI: 10.1159/000510399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 07/19/2020] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVE The first-line treatment for epilepsy, a chronic neurological disorder characterized by spontaneous seizures, includes the application of anticonvulsant drug therapy. Only one-third of patients are incapable of complete controlling of their seizures after the administration of ≥2 pharmaceuticals. Here, we aimed to observe the ultrastructure changes and the expression of ZnT3 and GFAP in the hippocampus of drug-resistant epileptic rats. METHODS A total of 50 healthy adult male SD rats were used to generate the model ofepilepsy by amygdala kindling. After the rats were successfully kindled, pharmacoresistant epileptic (PRE) rats were selected according to their response to phenobarbital and phenytoin. The ultrastructure as well as the expression of zinc transporter 3 (ZnT3, a member of a growing family of mammalian zinc transporters) and glial fibrillary acidic protein (GFAP) were compared among PRE, pharmacosensitive epileptic (PRE), and normal (NRC) rats. RESULTS The PRE rats displayed severe synapses, neuronal degeneration, and necrosis. Moreover, the expression of ZnT3 and GFAP was significantly increased in both PRE and PSE rats; compared with NRC rats, the promotion of this expression was more pronounced in the PRE rats. CONCLUSIONS Taken together, obvious synapses, neuronal degeneration, necrosis, mossy fiber sprouting, and astrogliosis were found in the drug-resistant epileptic rat model induced by amygdala kindling.
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Affiliation(s)
- Yuanxin Huang
- Department of Pain, the Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Lin Wang
- Department of Pain, the Affiliated Hospital of Guizhou Medical University, Guiyang, China,
| | - Siying Ren
- Department of Emergency, the Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Guofeng Wu
- Department of Emergency, the Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Jing Wu
- Graduate School of Guizhou Medical University, Guiyang, China
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Gruenbaum SE, Chen EC, Sandhu MRS, Deshpande K, Dhaher R, Hersey D, Eid T. Branched-Chain Amino Acids and Seizures: A Systematic Review of the Literature. CNS Drugs 2019; 33:755-770. [PMID: 31313139 DOI: 10.1007/s40263-019-00650-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Up to 40% of patients with epilepsy experience seizures despite treatment with antiepileptic drugs; however, branched-chain amino acid (BCAA) supplementation has shown promise in treating refractory epilepsy. OBJECTIVES The purpose of this systematic review was to evaluate all published studies that investigated the effects of BCAAs on seizures, emphasizing therapeutic efficacy and possible underlying mechanisms. METHODS On 31 January, 2017, the following databases were searched for relevant studies: MEDLINE (OvidSP), EMBASE (OvidSP), Scopus (Elsevier), the Cochrane Library, and the unindexed material in PubMed (National Library of Medicine/National Institutes of Health). The searches were repeated in all databases on 18 February, 2019. We only included full-length preclinical and clinical studies that were published in the English language that examined the effects of BCAA administration on seizures. RESULTS Eleven of 2045 studies met our inclusion criteria: ten studies were conducted in animal models and one study in human subjects. Seven seizure models were investigated: the strychnine (one study), pentylenetetrazole (two studies), flurothyl (one study), picrotoxin (two studies), genetic absence epilepsy in rats (one study), kainic acid (two studies), and methionine sulfoximine (one study) paradigms. Three studies investigated the effect of a BCAA mixture whereas the other studies explored the effects of individual BCAAs on seizures. In most animal models and in humans, BCAAs had potent anti-seizure effects. However, in the methionine sulfoximine model, long-term BCAA supplementation worsened seizure propagation and caused neuron loss, and in the genetic absence epilepsy in rats model, BCAAs exhibited pro-seizure effects. CONCLUSIONS The contradictory effects of BCAAs on seizure activity likely reflect differences in the complex mechanisms that underlie seizure disorders. Some of these mechanisms are likely mediated by BCAA's effects on glucose, glutamate, glutamine, and ammonia metabolism, activation of the mechanistic target of rapamycin signaling pathway, and their effects on aromatic amino acid transport and neurotransmitter synthesis. We propose that a better understanding of mechanisms by which BCAAs affect seizures and neuronal viability is needed to advance the field of BCAA supplementation in epilepsy.
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Affiliation(s)
- Shaun E Gruenbaum
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Jacksonville, FL, USA.
| | - Eric C Chen
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | | | - Ketaki Deshpande
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Roni Dhaher
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Denise Hersey
- Lewis Science Library, Princeton University, Princeton, NJ, USA
| | - Tore Eid
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
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Wang Y, Chen Z. An update for epilepsy research and antiepileptic drug development: Toward precise circuit therapy. Pharmacol Ther 2019; 201:77-93. [PMID: 31128154 DOI: 10.1016/j.pharmthera.2019.05.010] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 12/14/2022]
Abstract
Epilepsy involves neuronal dysfunction at molecular, cellular, and circuit levels. The understanding of the mechanism of the epilepsies has advanced greatly in the last three decades, especially in terms of their cellular and molecular basis. However, despite the availability of ~30 anti-epileptic drugs (AEDs) with diverse molecular targets, there are still many challenges (e.g. drug resistance, side effects) in pharmacological treatment of epilepsies today. Because molecular mechanisms are integrated at the level of neuronal circuits, we suggest a shift in epilepsy treatment and research strategies from the "molecular" level to the "circuit" level. Recent technological advances have facilitated circuit mechanistic discovery at each level and have paved the way for many opportunities of novel therapeutic strategies and AED development toward precise circuit therapy.
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Affiliation(s)
- Yi Wang
- Institute of Pharmacology and Toxicology, Department of Pharmacology, NHC and CAMS Key Laboratory of Medical Neurobiology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhong Chen
- Institute of Pharmacology and Toxicology, Department of Pharmacology, NHC and CAMS Key Laboratory of Medical Neurobiology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China; Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
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Packer RMA, Hobbs SL, Blackwell EJ. Behavioral Interventions as an Adjunctive Treatment for Canine Epilepsy: A Missing Part of the Epilepsy Management Toolkit? Front Vet Sci 2019; 6:3. [PMID: 30746367 PMCID: PMC6360160 DOI: 10.3389/fvets.2019.00003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/09/2019] [Indexed: 12/14/2022] Open
Abstract
Epilepsy is a common, complex and often challenging neurological disorder to treat in the dog, with 20-30% of dogs resistant to conventional medical therapies, and associated with cognitive and behavioral comorbidities and early death. Behavioral interventions are an emerging area of focus in the adjunctive treatment of drug-resistant human epilepsy patients, with studies indicating positive effects of a variety of interventions including relaxation-based techniques and behavioral therapy interventions. Behavioral interventions have the potential not only to improve seizure control, but also improve behavioral comorbidities and general quality of life in this hard to treat patient group. Despite striking similarities between human and canine epilepsy patients, including the recognition of co-morbid anxiety in epilepsy patients, behavioral interventions have yet to be studied in dogs. This is compounded by several licensed psychopharmaceutical agents for dogs being contra-indicated in epilepsy patients. We present evidence from human studies of the efficacy of behavioral interventions to improve seizure control, psychiatric comorbidities and quality of life, and propose that adapting such interventions for canine patients may be a valuable addition to the epilepsy management toolkit. There is a need for multi-center, double-blinded, placebo-controlled trials to confirm the effects of behavioral interventions on seizure frequency in veterinary medicine. In the absence of such evidence to date, the use of established behavioral medicine techniques to reduce stress and improve the mental health of these often sensitive and challenging patients is advocated, with a greater role for behaviorists in the management of epilepsy patients alongside neurologists and general practitioners.
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Affiliation(s)
| | | | - Emily J Blackwell
- Bristol Veterinary School, University of Bristol, Bristol, United Kingdom
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Brandt C, Seja P, Töllner K, Römermann K, Hampel P, Kalesse M, Kipper A, Feit PW, Lykke K, Toft-Bertelsen TL, Paavilainen P, Spoljaric I, Puskarjov M, MacAulay N, Kaila K, Löscher W. Bumepamine, a brain-permeant benzylamine derivative of bumetanide, does not inhibit NKCC1 but is more potent to enhance phenobarbital's anti-seizure efficacy. Neuropharmacology 2018; 143:186-204. [DOI: 10.1016/j.neuropharm.2018.09.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/30/2018] [Accepted: 09/16/2018] [Indexed: 01/01/2023]
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18
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Jia C, Han S, Wei L, Dang X, Niu Q, Chen M, Cao B, Liu Y, Jiao H. Protective effect of compound Danshen (Salvia miltiorrhiza) dripping pills alone and in combination with carbamazepine on kainic acid-induced temporal lobe epilepsy and cognitive impairment in rats. PHARMACEUTICAL BIOLOGY 2018; 56:217-224. [PMID: 29560767 PMCID: PMC6130614 DOI: 10.1080/13880209.2018.1432665] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
CONTEXT Temporal lobe epilepsy (TLE) is resistant to antiepileptic drugs (AEDs) and is associated with cognitive impairment. The modern Chinese medicine, compound Danshen dripping pills (CDDP), is clinically effective in treating epilepsy and improving cognitive impairment. OBJECTIVE This study evaluated the protective effects of CDDP alone and in combination with carbamazepine (CBZ) on kainic acid-induced TLE and cognitive impairment in rats. MATERIALS AND METHODS Sprague-Dawley rats were randomly divided into five groups: control (sham operated), model, CDDP, CBZ and combined. A TLE model was then created via bilateral intrahippocampal injection of 0.35 μg kainic acid (KA). Rats received CDDP (85 mg/kg), CBZ (100 mg/kg) or combined (85 mg/kg CDDP +100 mg/kg CBZ) via intragastric administration for 90 d, respectively. Seizure intensity, apoptosis and glial cell line-derived neurotrophic factor (GDNF) were measured. Furthermore, the improvement in cognitive impairment and hippocampal neuronal damage was evaluated. RESULTS CDDP combined with CBZ significantly decreased seizure severity and frequency (p < 0.05) and ameliorated cognitive impairment (p < 0.05). The model group showed a significant reduction of neurons and Bcl-2/Bax expression in the hippocampus CA3 area (p < 0.01), the combined groups significantly reversed these change (p < 0.01). GDNF expression in the combined groups showed a clear increase over the model group (p < 0.05). CONCLUSION These findings support the use of CDDP as an adjuvant drug for the treatment of TLE and cognitive deficit. Its mechanism might be related to an anti-apoptosis effect and up-regulation of GDNF.
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MESH Headings
- Animals
- Anticonvulsants/pharmacology
- Apoptosis/drug effects
- Behavior, Animal/drug effects
- CA3 Region, Hippocampal/drug effects
- CA3 Region, Hippocampal/metabolism
- CA3 Region, Hippocampal/pathology
- CA3 Region, Hippocampal/physiopathology
- Camphanes
- Carbamazepine/pharmacology
- Cognition/drug effects
- Cognitive Dysfunction/chemically induced
- Cognitive Dysfunction/physiopathology
- Cognitive Dysfunction/prevention & control
- Cognitive Dysfunction/psychology
- Disease Models, Animal
- Drug Therapy, Combination
- Drugs, Chinese Herbal/pharmacology
- Epilepsy, Temporal Lobe/metabolism
- Epilepsy, Temporal Lobe/pathology
- Epilepsy, Temporal Lobe/physiopathology
- Epilepsy, Temporal Lobe/prevention & control
- Escape Reaction/drug effects
- Glial Cell Line-Derived Neurotrophic Factor/metabolism
- Kainic Acid
- Male
- Maze Learning/drug effects
- Panax notoginseng
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Rats, Sprague-Dawley
- Reaction Time/drug effects
- Salvia miltiorrhiza
- Time Factors
- bcl-2-Associated X Protein/metabolism
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Affiliation(s)
- Chen Jia
- Department of Pharmacy, Lanzhou University Second Hospital, Lanzhou, China
| | - Shanshan Han
- Department of Pharmacy, Huaihe Hospital of Henan University, Kaifeng, China
| | - Liming Wei
- Department of Pharmacy, Lanzhou University Second Hospital, Lanzhou, China
| | - Xiangji Dang
- Department of Pharmacy, Lanzhou University Second Hospital, Lanzhou, China
| | - Qianqian Niu
- College of Pharmacy, Lanzhou University, Lanzhou, China
| | - Mengyu Chen
- College of Pharmacy, Lanzhou University, Lanzhou, China
| | - Boqun Cao
- College of Pharmacy, Lanzhou University, Lanzhou, China
| | - Yuting Liu
- College of Pharmacy, Lanzhou University, Lanzhou, China
| | - Haisheng Jiao
- Department of Pharmacy, Lanzhou University Second Hospital, Lanzhou, China
- CONTACT Haisheng JiaoDepartment of Pharmacy, Lanzhou University Second Hospital, Lanzhou730030, China
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Rigas P, Sigalas C, Nikita M, Kaplanian A, Armaos K, Leontiadis LJ, Zlatanos C, Kapogiannatou A, Peta C, Katri A, Skaliora I. Long-Term Effects of Early Life Seizures on Endogenous Local Network Activity of the Mouse Neocortex. Front Synaptic Neurosci 2018; 10:43. [PMID: 30538627 PMCID: PMC6277496 DOI: 10.3389/fnsyn.2018.00043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 11/06/2018] [Indexed: 12/17/2022] Open
Abstract
Understanding the long term impact of early life seizures (ELS) is of vital importance both for researchers and clinicians. Most experimental studies of how seizures affect the developing brain have drawn their conclusions based on changes detected at the cellular or behavioral level, rather than on intermediate levels of analysis, such as the physiology of neuronal networks. Neurons work as part of networks and network dynamics integrate the function of molecules, cells and synapses in the emergent properties of brain circuits that reflect the balance of excitation and inhibition in the brain. Therefore, studying network dynamics could help bridge the cell-to-behavior gap in our understanding of the neurobiological effects of seizures. To this end we investigated the long-term effects of ELS on local network dynamics in mouse neocortex. By using the pentylenetetrazole (PTZ)-induced animal model of generalized seizures, single or multiple seizures were induced at two different developmental stages (P9-15 or P19-23) in order to examine how seizure severity and brain maturational status interact to affect the brain's vulnerability to ELS. Cortical physiology was assessed by comparing spontaneous network activity (in the form of recurring Up states) in brain slices of adult (>5 mo) mice. In these experiments we examined two distinct cortical regions, the primary motor (M1) and somatosensory (S1) cortex in order to investigate regional differences in vulnerability to ELS. We find that the effects of ELSs vary depending on (i) the severity of the seizures (e.g., single intermittent ELS at P19-23 had no effect on Up state activity, but multiple seizures induced during the same period caused a significant change in the spectral content of spontaneous Up states), (ii) the cortical area examined, and (iii) the developmental stage at which the seizures are administered. These results reveal that even moderate experiences of ELS can have long lasting age- and region-specific effects in local cortical network dynamics.
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Affiliation(s)
- Pavlos Rigas
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | | | - Maria Nikita
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Ani Kaplanian
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | | | | | - Christos Zlatanos
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | | | - Charoula Peta
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Anna Katri
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Irini Skaliora
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
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Campos G, Fortuna A, Falcão A, Alves G. In vitro and in vivo experimental models employed in the discovery and development of antiepileptic drugs for pharmacoresistant epilepsy. Epilepsy Res 2018; 146:63-86. [PMID: 30086482 DOI: 10.1016/j.eplepsyres.2018.07.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 06/16/2018] [Accepted: 07/20/2018] [Indexed: 12/23/2022]
Abstract
Epilepsy is one of the most common chronic, recurrent and progressive neurological diseases. In spite of the large number of antiepileptic drugs currently available for the suppression of seizures, about one-third of patients develop drug-resistant epilepsy, even when they are administered the most appropriate treatment available. Thus, nonclinical models can be valuable tools for the elucidation of the mechanisms underlying the development of pharmacoresistance and also for the development of new therapeutic agents that may be promising therapeutic approaches for this unmet medical need. Up today, several epilepsy and seizure models have been developed, exhibiting similar physiopathological features of human drug-resistant epilepsy; moreover, pharmacological response to antiepileptic drugs clinically available tends to be similar in animal models and humans. Therefore, they should be more intensively used in the preclinical discovery and development of new candidates to antiepileptic drugs. Although useful, in vitro models cannot completely replicate the complexity of a living being and their potential for a systematic use in antiepileptic drug screening is limited. The whole-animal models are the most commonly employed and they can be classified as per se drug-resistant due to an inherent poor drug response or be based on the selection of subgroups of epileptic animals that respond or not to a specific antiepileptic drug. Although more expensive and time-consuming, the latter are chronic models of epilepsy that better exhibit the disease-associated alterations found in human epilepsy. Several antiepileptic drugs in development or already marketed have been already tested and shown to be effective in these models of drug-resistant epilepsy, constituting a new hope for the treatment of drug-resistant epilepsy. This review will provide epilepsy researchers with detailed information on the in vitro and in vivo nonclinical models of interest in drug-resistant epilepsy, which may enable a refined selection of most relevant models for understanding the mechanisms of the disease and developing novel antiepileptic drugs.
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Affiliation(s)
- Gonçalo Campos
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506, Covilhã, Portugal
| | - Ana Fortuna
- CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Portugal; Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548, Coimbra, Portugal
| | - Amílcar Falcão
- CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Portugal; Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548, Coimbra, Portugal
| | - Gilberto Alves
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506, Covilhã, Portugal.
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Salgado PRR, da Fonsêca DV, de Melo CGF, Leite FC, Alves AF, Ferreira PB, Piuvezam MR, de Sousa DP, de Almeida RN. Comparison of behavioral, neuroprotective, and proinflammatory cytokine modulating effects exercised by (+)-cis-EC and (-)-cis-EC stereoisomers in a PTZ-induced kindling test in mice. Fundam Clin Pharmacol 2018; 32:507-515. [PMID: 29577374 DOI: 10.1111/fcp.12366] [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] [Received: 05/21/2017] [Revised: 03/05/2018] [Accepted: 03/20/2018] [Indexed: 01/01/2023]
Abstract
Epoxy-carvone (EC) has chiral centers that allow generation of stereoisomers, including (+)-cis-EC and (-)-cis-EC, whose effects in the kindling tests have never been studied. Accordingly, this study aims to comparatively investigate the effect of stereoisomers (+)-cis-epoxy-carvone and (-)-cis-epoxy-carvone on behavioral changes measured in scores, in the levels of cytokines (IL-1β, IL-6, and TNFα) and neuronal protection in the face of continuous treatment with pentylenetetrazol. Swiss mice were divided into five groups (n = 10), receiving vehicle, (+) - cis-EC, (-) - cis-EC (both at the dose of 30 mg/kg), and diazepam (4 mg/kg). Thirty minutes after the respective treatment was administered to the animals one subconvulsive dose of PTZ (35 mg/kg). Seven subconvulsives treatments were made on alternate days, in which each treatment several parameters were recorded. In the eighth treatment, the animals receiving the highest dose of PTZ (75 mg/kg) and were sacrificed for quantification of cytokines and histopathologic analysis. All drugs were administered by intraperitoneal route. In the kindling test, (+)-cis-EC and (-)-cis-EC reduced the average scores. The stereoisomer (+)-cis-EC decreased levels of proinflammatory cytokines IL-1β, IL-6, and TNFα, whereas comparatively (-)-cis-EC did not reduce IL-1β levels. Histopathological analysis of the mice hippocampi undergoing this methodology showed neural protection for treated with (+)-cis-EC. The results suggest that the anticonvulsant effect of (+)-cis-EC possibly takes place due to reduction of proinflammatory cytokines involved in the epileptogenic process, besides neuronal protection, yet further investigation of the mechanisms involved is required.
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Affiliation(s)
- Paula Regina Rodrigues Salgado
- Programa de Pós-graduação em Desenvolvimento e Inovação Tecnológica em Medicamentos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Diogo Vilar da Fonsêca
- Programa de Pós-graduação em Produtos Naturais e Sintéticos Bioativos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Cynthia Germoglio Farias de Melo
- Programa de Pós-graduação em Produtos Naturais e Sintéticos Bioativos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Fagner Carvalho Leite
- Programa de Pós-graduação em Produtos Naturais e Sintéticos Bioativos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Adriano Francisco Alves
- Programa de Pós-graduação em Produtos Naturais e Sintéticos Bioativos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Paula Benvindo Ferreira
- Programa de Pós-graduação em Produtos Naturais e Sintéticos Bioativos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Márcia Regina Piuvezam
- Programa de Pós-graduação em Desenvolvimento e Inovação Tecnológica em Medicamentos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil.,Departamento de Fisiologia e Patologia, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Damião Pergentino de Sousa
- Programa de Pós-graduação em Desenvolvimento e Inovação Tecnológica em Medicamentos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil.,Departamento de Ciências Farmacêuticas, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
| | - Reinaldo Nóbrega de Almeida
- Programa de Pós-graduação em Desenvolvimento e Inovação Tecnológica em Medicamentos, Instituto de Pesquisa em Fármacos e Medicamentos, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil.,Departamento de Fisiologia e Patologia, Universidade Federal da Paraíba, CP 5009, João Pessoa, CEP 58051-900, Paraíba, Brazil
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22
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Hartmann A, von Klopmann C, Lautenschläger IE, Scholz VB, Schmidt MJ. Quantitative analysis of brain perfusion parameters in dogs with idiopathic epilepsy by use of magnetic resonance imaging. Am J Vet Res 2018; 79:433-442. [DOI: 10.2460/ajvr.79.4.433] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Frank L, Lüpke M, Kostic D, Löscher W, Tipold A. Grey matter volume in healthy and epileptic beagles using voxel-based morphometry - a pilot study. BMC Vet Res 2018; 14:50. [PMID: 29463250 PMCID: PMC5819682 DOI: 10.1186/s12917-018-1373-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Accepted: 02/14/2018] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND One of the most common chronic neurological disorders in dogs is idiopathic epilepsy (IE) diagnosed as epilepsy without structural changes in the brain. In the current study the hypothesis should be proven that subtle grey matter changes occur in epileptic dogs. Therefore, magnetic resonance (MR) images of one dog breed (Beagles) were used to obtain an approximately uniform brain shape. Local differences in grey matter volume (GMV) were compared between 5 healthy Beagles and 10 Beagles with spontaneously recurrent seizures (5 dogs with IE and 5 dogs with structural epilepsy (SE)), using voxel-based morphometry (VBM). T1W images of all dogs were prepared using Amira 6.3.0 for brain extraction, FSL 4.1.8 for registration and SPM12 for realignment. After creation of tissue probability maps of cerebrospinal fluid, grey and white matter from control images to segment all extracted brains, GM templates for each group were constructed to normalize brain images for parametric statistical analysis, which was achieved using SPM12. RESULTS Epileptic Beagles (IE and SE Beagles) displayed statistically significant reduced GMV in olfactory bulb, cingulate gyrus, hippocampus and cortex, especially in temporal and occipital lobes. Beagles with IE showed statistically significant decreased GMV in olfactory bulb, cortex of parietal and temporal lobe, hippocampus and cingulate gyrus, Beagles with SE mild statistically significant GMV reduction in temporal lobe (p < 0.05; family- wise error correction). CONCLUSION These results suggest that, as reported in epileptic humans, focal reduction in GMV also occurs in epileptic dogs. Furthermore, the current study shows that VBM analysis represents an excellent method to detect GMV differences of the brain between a healthy dog group and dogs with epileptic syndrome, when MR images of one breed are used.
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Affiliation(s)
- Lisa Frank
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany.
| | - Matthias Lüpke
- Department of General Radiology and Medical Physics, University of Veterinary Medicine, Hannover, Germany
| | - Draginja Kostic
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
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Seizure liability assessments using the hippocampal tissue slice: Comparison of non-clinical species. J Pharmacol Toxicol Methods 2017; 93:59-68. [PMID: 29155282 DOI: 10.1016/j.vascn.2017.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 09/29/2017] [Accepted: 11/13/2017] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Traditionally, rat hippocampal tissue slice models are used as an in vitro electrophysiology assay to assess seizurogenic potential in early drug development despite non-clinical species-specific differences noted during in vivo seizure studies. METHODS Hippocampal tissue slices were acutely isolated from rats, minipigs, dogs and nonhuman primates (NHP). Population spikes (PS) were evoked through stimulation of the CA3 Schaffer collateral pathway and recorded using in vitro electrophysiological techniques via an extracellular electrode placed within the CA1 stratum pyramidale cell body layer. RESULTS Hippocampal slices, across all species, displayed a concentration-dependent increase in PS area and number with the pro-convulsant pentylenetetrazol (PTZ; 0.1-10mM). Beagle dogs exhibited higher sensitivities to PTZ-induced changes in PS area and number compared to both rats and NHPs which presented nuanced differences in their responsiveness to PTZ modulation. Minipigs were comparatively resistant to PTZ-induced changes in both PS area and number. Rat and NHP hippocampal tissues were further characterized with the pro-convulsant agents 4-aminopyradine (4-AP; 1-100μM) and cefazolin (0.001-10mM). Rats possessed higher sensitivities to 4-AP- and cefazolin-induced changes to both PS area and number whereas NHP displayed greater modulation in PS duration. The anti-convulsant agents, diazepam (10-500μM) and lidocaine (1-500μM), were also tested on either rat and/or NHP tissue with both drugs repressing PS activation at high concentrations. DISCUSSION Hippocampal tissue slices, across all species, possessed distinct sensitivities to pro- and anti-convulsant agents which may benefit the design of non-clinical seizure liability studies and their associated data interpretation.
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Hartmann A, Sager S, Failing K, Sparenberg M, Schmidt MJ. Diffusion-weighted imaging of the brains of dogs with idiopathic epilepsy. BMC Vet Res 2017; 13:338. [PMID: 29141638 PMCID: PMC5688626 DOI: 10.1186/s12917-017-1268-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/10/2017] [Indexed: 02/07/2023] Open
Abstract
Background Idiopathic epilepsy is one of the most common neurological disorders in dogs. Unfortunately, up to 30% of dogs with idiopathic epilepsy show no improvement under antiepileptic drug treatment. Diffusion-weighted imaging is used in human medicine to identify epileptogenic foci in the brain to allow for more invasive treatments such as deep brain stimulation or surgical removal. The aim of this study was to ass the feasibility of interictal diffusion-weighted MRI in dogs and to evaluate the distribution of diffusion in the brains of dogs with idiopathic epilepsy (IE) and to compare these values to previously published values from healthy beagle dogs. Client-owned dogs with the final diagnosis of IE were included in this study. MRI examination was carried out using a 1.0Tesla superconductive magnet. Diffusion-weighted images using a single shot echo planar imaging sequence (SSh-EPI) with a b value of b = 0 s/mm2 and b = 800 s/mm2 were acquired in a dorsal and transverse plane with diffusion gradients in all three planes (x-, y- and z-plane). An ADC (apparent diffusion coefficient) map of the isometric image of each acquired slice was generated. Regions of interest (ROIs) were manually drawn around the caudate nucleus, the thalamus, the piriform lobe including the amygdala, the hippocampus, the semioval center and the temporal cerebral cortex by one of the authors. ROI drawings were repeated 5 times at different time points to assess intra-obersver variability. A multi-way mixed-model analysis of variance (ANOVA) and two-way ANOVA were used during statistical analysis. A p value of p < 0.05 was considered significant. Results Dogs with IE showed a significantly increased ADC in the amygdala within the piriform lobe and in the semioval center (p < 0.05) compared with the healthy control group. Conclusion Changes in the piriform lobe in cases of epilepsy are reported infrequently in human and veterinary medicine. Similar to our results, ADC changes in the interictal phase usually include an increase in ADC due to cell loss and increased intercellular spaces. Diffusion MRI might be a promising technique for the examination of canine epileptic patients lacking other gross neuromorphological abnormalities.
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Affiliation(s)
- Antje Hartmann
- Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Länggassstraße 128, 3012, Bern, Switzerland.
| | - Steffen Sager
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University Giessen, Frankfurter Straße 108, 35392, Giessen, Germany
| | - Klaus Failing
- Unit for Biomathematics and Data Processing Faculty of Veterinary Medicine Justus Liebig-University, Frankfurter Straße 95, 35392, Giessen, Germany
| | - Marion Sparenberg
- Unit for Biomathematics and Data Processing Faculty of Veterinary Medicine Justus Liebig-University, Frankfurter Straße 95, 35392, Giessen, Germany
| | - Martin J Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University Giessen, Frankfurter Straße 108, 35392, Giessen, Germany
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Panomvana D, Methaneethorn J, Vachirayonstien T. Correlation Between Elimination Parameters of Phenytoin and Carbamazepine in Patients with Epilepsy Receiving Both Drugs Concomitantly: A Preliminary Study. Pharmaceut Med 2017. [DOI: 10.1007/s40290-017-0182-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Barker-Haliski ML, Johnson K, Billingsley P, Huff J, Handy LJ, Khaleel R, Lu Z, Mau MJ, Pruess TH, Rueda C, Saunders G, Underwood TK, Vanegas F, Smith MD, West PJ, Wilcox KS. Validation of a Preclinical Drug Screening Platform for Pharmacoresistant Epilepsy. Neurochem Res 2017; 42:1904-1918. [PMID: 28303498 DOI: 10.1007/s11064-017-2227-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/07/2017] [Accepted: 03/09/2017] [Indexed: 12/11/2022]
Abstract
The successful identification of promising investigational therapies for the treatment of epilepsy can be credited to the use of numerous animal models of seizure and epilepsy for over 80 years. In this time, the maximal electroshock test in mice and rats, the subcutaneous pentylenetetrazol test in mice and rats, and more recently the 6 Hz assay in mice, have been utilized as primary models of electrically or chemically-evoked seizures in neurologically intact rodents. In addition, rodent kindling models, in which chronic network hyperexcitability has developed, have been used to identify new agents. It is clear that this traditional screening approach has greatly expanded the number of marketed drugs available to manage the symptomatic seizures associated with epilepsy. In spite of the numerous antiseizure drugs (ASDs) on the market today, the fact remains that nearly 30% of patients are resistant to these currently available medications. To address this unmet medical need, the National Institute of Neurological Disorders and Stroke (NINDS) Epilepsy Therapy Screening Program (ETSP) revised its approach to the early evaluation of investigational agents for the treatment of epilepsy in 2015 to include a focus on preclinical approaches to model pharmacoresistant seizures. This present report highlights the in vivo and in vitro findings associated with the initial pharmacological validation of this testing approach using a number of mechanistically diverse, commercially available antiseizure drugs, as well as several probe compounds that are of potential mechanistic interest to the clinical management of epilepsy.
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Affiliation(s)
| | - Kristina Johnson
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Peggy Billingsley
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Jennifer Huff
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Laura J Handy
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Rizvana Khaleel
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Zhenmei Lu
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Matthew J Mau
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Timothy H Pruess
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Carlos Rueda
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Gerald Saunders
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Tristan K Underwood
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Fabiola Vanegas
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA
| | - Misty D Smith
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA.,Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Peter J West
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA.,Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Karen S Wilcox
- Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, 84112, USA.,Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, 84112, USA
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Chi X, Huang C, Li R, Wang W, Wu M, Li J, Zhou D. Inhibition of mTOR Pathway by Rapamycin Decreases P-glycoprotein Expression and Spontaneous Seizures in Pharmacoresistant Epilepsy. J Mol Neurosci 2017; 61:553-562. [PMID: 28229367 DOI: 10.1007/s12031-017-0897-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 02/08/2017] [Indexed: 02/05/2023]
Abstract
The mammalian target of rapamycin (mTOR) has been demonstrated to mediate multidrug resistance in various tumors by inducing P-glycoprotein (P-gp) overexpression. Here, we investigated the correlation between the mTOR pathway and P-gp expression in pharmacoresistant epilepsy. Temporal cortex specimens were obtained from patients with refractory mesial temporal lobe epilepsy (mTLE) and age-matched controls who underwent surgeries at West China Hospital of Sichuan University between June 2014 and May 2015. We established a rat model of epilepsy kindled by coriaria lactone (CL) and screened pharmacoresistant rats (non-responders) using phenytoin. Non-responders were treated for 4 weeks with vehicle only or with the mTOR pathway inhibitor rapamycin at doses of 1, 3, and 6 mg/kg. Western blotting and immunohistochemistry were used to detect the expression of phospho-S6 (P-S6) and P-gp at different time points (1 h, 8 h, 1 day, 3 days, 1 weeks, 2 weeks, and 4 weeks) after the onset of treatment. Overexpression of P-S6 and P-gp was detected in both refractory mTLE patients and non-responder rats. Rapamycin showed an inhibitory effect on P-S6 and P-gp expression 1 week after treatment in rats. In addition, the expression levels of P-S6 and P-gp in the 6 mg/kg group were significantly lower than those in the 1 mg/kg or the 3 mg/kg group at the same time points (all P < 0.05). Moreover, rapamycin decreased the duration and number of CL-induced seizures, as well as the stage of non-responders (all P < 0.05). The current study indicates that the mTOR signaling pathway plays a critical role in P-gp expression in drug-resistant epilepsy. Inhibition of the mTOR pathway by rapamycin may be a potential therapeutic approach for pharmacoresistant epilepsy.
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Affiliation(s)
- Xiaosa Chi
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Cheng Huang
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Rui Li
- Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Wei Wang
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Mengqian Wu
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Jinmei Li
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Dong Zhou
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China.
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Hussein AM, Abbas KM, Abulseoud OA, El-Hussainy EHMA. Effects of ferulic acid on oxidative stress, heat shock protein 70, connexin 43, and monoamines in the hippocampus of pentylenetetrazole-kindled rats. Can J Physiol Pharmacol 2017; 95:732-742. [PMID: 28177659 DOI: 10.1139/cjpp-2016-0219] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study investigated the effects of ferulic acid (FA) on pentylenetetrazole (PTZ)-induced seizures, oxidative stress markers (malondialdehyde (MDA), catalase, and reduced glutathione (GSH)), connexin (Cx) 43, heat shock protein 70 (Hsp 70), and monoamines (serotonin (5-HT) and norepinephrine (NE)) levels in a rat model of PTZ-induced kindling. Sixty Sprague Dawley rats were divided into 5 equal groups: (a) normal group; (b) FA group: normal rats received FA at a dose of 40 mg/kg daily; (c) PTZ group: normal rats received PTZ at a dose of 50 mg/kg i.p. on alternate days for 15 days; (d) FA-before group: treatment was the same as for the PTZ group, except rats received FA; and (e) FA-after group: rats received FA from sixth dose of PTZ. PTZ caused a significant increase in MDA, Cx43, and Hsp70 along with a significant decrease in GSH, 5-HT, and NE levels and CAT activity in the hippocampus (p < 0.05). Pre- and post-treatment with FA caused significant improvement in behavioral parameters, MDA, CAT, GSH, 5-HT, NE, Cx43 expression, and Hsp70 expression in the hippocampal region (p < 0.05). We conclude that FA has neuroprotective effects in PTZ-induced epilepsy, which might be due to attenuation of oxidative stress and Cx43 expression and upregulation of neuroprotective Hsp70 and neurotransmitters (5-HT and NE).
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Affiliation(s)
- Abdelaziz M Hussein
- a Faculty of Medicine, Mansoura University, El Gomhoria Street, Mansoura, Egypt
| | - Khaled M Abbas
- a Faculty of Medicine, Mansoura University, El Gomhoria Street, Mansoura, Egypt
| | - Osama A Abulseoud
- b Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Biomedical Research Center, 251 Bayview Boulevard, Baltimore, MD 21224, USA
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Nôga DAMF, Brandão LEM, Cagni FC, Silva D, de Azevedo DLO, Araújo A, Dos Santos WF, Miranda A, da Silva RH, Ribeiro AM. Anticonvulsant Effects of Fractions Isolated from Dinoponera quadriceps (Kempt) Ant Venom (Formicidae: Ponerinae). Toxins (Basel) 2016; 9:toxins9010005. [PMID: 28025529 PMCID: PMC5308238 DOI: 10.3390/toxins9010005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 10/24/2016] [Accepted: 11/01/2016] [Indexed: 12/13/2022] Open
Abstract
Natural products, sources of new pharmacological substances, have large chemical diversity and architectural complexity. In this context, some toxins obtained from invertebrate venoms have anticonvulsant effects. Epilepsy is a neurological disorder that affects about 65 million people worldwide, and approximately 30% of cases are resistant to pharmacological treatment. Previous studies from our group show that the denatured venom of the ant Dinoponera quadriceps (Kempt) protects mice against bicuculline (BIC)-induced seizures and death. The aim of this study was to investigate the anticonvulsant activity of compounds isolated from D. quadriceps venom against seizures induced by BIC in mice. Crude venom was fractionated by high-performance liquid chromatography (HPLC) resulting in six fractions referred to as DqTx1-DqTx6. A liquid chromatography-mass spectrometry (LC/MS) analysis revealed a major 431 Da compound in fractions DqTx1 and DqTx2. Fractions DqTx3 and DqTx4 showed a compound of 2451 Da and DqTx5 revealed a 2436 Da compound. Furthermore, the DqTx6 fraction exhibited a major component with a molecular weight of 13,196 Da. Each fraction (1 mg/mL) was microinjected into the lateral ventricle of mice, and the animals were observed in an open field. We did not observe behavioral alterations when the fractions were given alone. Conversely, when the fractions were microinjected 20 min prior to the administration of BIC (21.6 nM), DqTx1, DqTx4, and DqTx6 fractions increased the latency for onset of tonic-clonic seizures. Moreover, all fractions, except DqTx5, increased latency to death. The more relevant result was obtained with the DqTx6 fraction, which protected 62.5% of the animals against tonic-clonic seizures. Furthermore, this fraction protected 100% of the animals from seizure episodes followed by death. Taken together, these findings indicate that compounds from ant venom might be a potential source of new anticonvulsants molecules.
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Affiliation(s)
| | | | - Fernanda Carvalho Cagni
- Physiology Department, University Federal of Rio Grande of Norte, Natal, RN 59078-970, Brazil.
| | - Delano Silva
- Physiology Department, University Federal of Rio Grande of Norte, Natal, RN 59078-970, Brazil.
| | | | - Arrilton Araújo
- Physiology Department, University Federal of Rio Grande of Norte, Natal, RN 59078-970, Brazil.
| | | | - Antonio Miranda
- Biophysics Department, Federal University of São Paulo, São Paulo, SP 04023-062, Brazil.
| | - Regina Helena da Silva
- Pharmacology Department, Federal University of São Paulo, São Paulo, SP 04023-062, Brazil.
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Löscher W, Gillard M, Sands ZA, Kaminski RM, Klitgaard H. Synaptic Vesicle Glycoprotein 2A Ligands in the Treatment of Epilepsy and Beyond. CNS Drugs 2016; 30:1055-1077. [PMID: 27752944 PMCID: PMC5078162 DOI: 10.1007/s40263-016-0384-x] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The synaptic vesicle glycoprotein SV2A belongs to the major facilitator superfamily (MFS) of transporters and is an integral constituent of synaptic vesicle membranes. SV2A has been demonstrated to be involved in vesicle trafficking and exocytosis, processes crucial for neurotransmission. The anti-seizure drug levetiracetam was the first ligand to target SV2A and displays a broad spectrum of anti-seizure activity in various preclinical models. Several lines of preclinical and clinical evidence, including genetics and protein expression changes, support an important role of SV2A in epilepsy pathophysiology. While the functional consequences of SV2A ligand binding are not fully elucidated, studies suggest that subsequent SV2A conformational changes may contribute to seizure protection. Conversely, the recently discovered negative SV2A modulators, such as UCB0255, counteract the anti-seizure effect of levetiracetam and display procognitive properties in preclinical models. More broadly, dysfunction of SV2A may also be involved in Alzheimer's disease and other types of cognitive impairment, suggesting potential novel therapies for levetiracetam and its congeners. Furthermore, emerging data indicate that there may be important roles for two other SV2 isoforms (SV2B and SV2C) in the pathogenesis of epilepsy, as well as other neurodegenerative diseases. Utilization of recently developed SV2A positron emission tomography ligands will strengthen and reinforce the pharmacological evidence that SV2A is a druggable target, and will provide a better understanding of its role in epilepsy and other neurological diseases, aiding in further defining the full therapeutic potential of SV2A modulation.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, 30559, Hannover, Germany.
- Center for Systems Neuroscience, Hannover, Germany.
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Diagnostic techniques to detect the epileptogenic zone: Pathophysiological and presurgical analysis of epilepsy in dogs and cats. Vet J 2016; 215:64-75. [DOI: 10.1016/j.tvjl.2016.03.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 02/24/2016] [Accepted: 03/05/2016] [Indexed: 12/17/2022]
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Study of the anti-seizure effects of low-frequency stimulation following kindling (a review of the cellular mechanism related to the anti-seizure effects of low-frequency electrical stimulation). Neurol Sci 2016; 38:19-26. [DOI: 10.1007/s10072-016-2694-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 08/17/2016] [Indexed: 02/04/2023]
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Brown DC. Resiniferatoxin: The Evolution of the "Molecular Scalpel" for Chronic Pain Relief. Pharmaceuticals (Basel) 2016; 9:ph9030047. [PMID: 27529257 PMCID: PMC5039500 DOI: 10.3390/ph9030047] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/04/2016] [Accepted: 08/09/2016] [Indexed: 11/16/2022] Open
Abstract
Control of chronic pain is frequently inadequate or can be associated with debilitating side effects. Ablation of certain nociceptive neurons, while retaining all other sensory modalities and motor function, represents a new therapeutic approach to controlling severe pain while avoiding off-target side effects. transient receptor potential cation channel subfamily V member 1 (TRPV1) is a calcium permeable nonselective cation channel expressed on the peripheral and central terminals of small-diameter sensory neurons. Highly selective chemoablation of TRPV1-containing peripheral nerve endings, or the entire TRPV1-expressing neuron itself, can be used to control chronic pain. Administration of the potent TRPV1 agonist resiniferatoxin (RTX) to neuronal perikarya or nerve terminals induces calcium cytotoxicity and selective lesioning of the TRPV1-expressing nociceptive primary afferent population. This selective neuroablation has been coined "molecular neurosurgery" and has the advantage of sparing motor, proprioceptive, and other somatosensory functions that are so important for coordinated movement, performing activities of daily living, and maintaining quality of life. This review examines the mechanisms and preclinical data underlying the therapeutic use of RTX and examples of such use for the management of chronic pain in clinical veterinary and human pain states.
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Affiliation(s)
- Dorothy Cimino Brown
- Department of Clinical Studies-Philadelphia, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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The Search for New Screening Models of Pharmacoresistant Epilepsy: Is Induction of Acute Seizures in Epileptic Rodents a Suitable Approach? Neurochem Res 2016; 42:1926-1938. [DOI: 10.1007/s11064-016-2025-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 07/22/2016] [Accepted: 07/29/2016] [Indexed: 10/21/2022]
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Fit for purpose application of currently existing animal models in the discovery of novel epilepsy therapies. Epilepsy Res 2016; 126:157-84. [PMID: 27505294 DOI: 10.1016/j.eplepsyres.2016.05.016] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 03/06/2016] [Accepted: 05/30/2016] [Indexed: 01/10/2023]
Abstract
Animal seizure and epilepsy models continue to play an important role in the early discovery of new therapies for the symptomatic treatment of epilepsy. Since 1937, with the discovery of phenytoin, almost all anti-seizure drugs (ASDs) have been identified by their effects in animal models, and millions of patients world-wide have benefited from the successful translation of animal data into the clinic. However, several unmet clinical needs remain, including resistance to ASDs in about 30% of patients with epilepsy, adverse effects of ASDs that can reduce quality of life, and the lack of treatments that can prevent development of epilepsy in patients at risk following brain injury. The aim of this review is to critically discuss the translational value of currently used animal models of seizures and epilepsy, particularly what animal models can tell us about epilepsy therapies in patients and which limitations exist. Principles of translational medicine will be used for this discussion. An essential requirement for translational medicine to improve success in drug development is the availability of animal models with high predictive validity for a therapeutic drug response. For this requirement, the model, by definition, does not need to be a perfect replication of the clinical condition, but it is important that the validation provided for a given model is fit for purpose. The present review should guide researchers in both academia and industry what can and cannot be expected from animal models in preclinical development of epilepsy therapies, which models are best suited for which purpose, and for which aspects suitable models are as yet not available. Overall further development is needed to improve and validate animal models for the diverse areas in epilepsy research where suitable fit for purpose models are urgently needed in the search for more effective treatments.
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Functionalized nanocarrier combined seizure-specific vector with P-glycoprotein modulation property for antiepileptic drug delivery. Biomaterials 2016; 74:64-76. [DOI: 10.1016/j.biomaterials.2015.09.041] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 09/24/2015] [Accepted: 09/26/2015] [Indexed: 01/07/2023]
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Davis KA, Ung H, Wulsin D, Wagenaar J, Fox E, Patterson N, Vite C, Worrell G, Litt B. Mining continuous intracranial EEG in focal canine epilepsy: Relating interictal bursts to seizure onsets. Epilepsia 2016; 57:89-98. [PMID: 26608448 PMCID: PMC4770560 DOI: 10.1111/epi.13249] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2015] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Brain regions are localized for resection during epilepsy surgery based on rare seizures observed during a short period of intracranial electroencephalography (iEEG) monitoring. Interictal epileptiform bursts, which are more prevalent than seizures, may provide complementary information to aid in epilepsy evaluation. In this study, we leverage a long-term iEEG dataset from canines with naturally occurring epilepsy to investigate interictal bursts and their electrographic relationship to seizures. METHODS Four dogs were included in this study, each monitored previously with continuous iEEG for periods of 475.7, 329.9, 45.8, and 451.8 days, respectively, for a total of >11,000 h. Seizures and bursts were detected and validated by two board-certified epileptologists. A published Bayesian model was applied to analyze the dynamics of interictal epileptic bursts on EEG and compare them to seizures. RESULTS In three dogs, bursts were stereotyped and found to be statistically similar to periods before or near seizure onsets. Seizures from one dog during status epilepticus were markedly different from other seizures in terms of burst similarity. SIGNIFICANCE Shorter epileptic bursts explored in this work have the potential to yield significant information about the distribution of epileptic events. In our data, bursts are at least an order of magnitude more prevalent than seizures and occur much more regularly. Our finding that bursts often display pronounced similarity to seizure onsets suggests that they contain relevant information about the epileptic networks from which they arise and may aide in the clinical evaluation of epilepsy in patients.
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Affiliation(s)
- Kathryn A. Davis
- Department of Neurology, University of Pennsylvania
- Penn Epilepsy Center, University of Pennsylvania
- Penn Center for Neuroengineering and Therapeutics
| | - Hoameng Ung
- Department of Bioengineering, University of Pennsylvania
- Penn Center for Neuroengineering and Therapeutics
| | - Drausin Wulsin
- Department of Bioengineering, University of Pennsylvania
| | | | - Emily Fox
- Department of Statistics, University of Washington
| | - Ned Patterson
- Department of Veterinary Clinical Sciences, University of Minnesota
| | - Charles Vite
- School of Veterinary Medicine, University of Pennsylvania
| | | | - Brian Litt
- Department of Neurology, University of Pennsylvania
- Penn Epilepsy Center, University of Pennsylvania
- Department of Bioengineering, University of Pennsylvania
- Penn Center for Neuroengineering and Therapeutics
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Cortez MA, Kostopoulos GK, Snead OC. Acute and chronic pharmacological models of generalized absence seizures. J Neurosci Methods 2015; 260:175-84. [PMID: 26343323 DOI: 10.1016/j.jneumeth.2015.08.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/28/2015] [Accepted: 08/30/2015] [Indexed: 12/28/2022]
Abstract
This article reviews the contribution of pharmacologically induced acute and chronic animal models to our understanding of epilepsies featuring non-convulsive generalized seizures, the typical and atypical absence seizures. Typical absences comprise about 5% of all epilepsies regardless of age and the atypical ones are even more common. Although absence epilepsy was thought to be relatively benign, children with childhood epilepsy (CAE) turn out to have a high rate of pretreatment attention deficits that persist despite seizure freedom. The phenomenon of the absence seizure has long attracted research interest because of the clear temporal relationship of the conspicuous EEG rhythm of 3 Hz generalized spike and wave discharges (GSWD) and the parallel transient "loss of consciousness" characterizing these seizures which is time-locked with the GSWD. Indeed, clinical epileptologists, basic scientists and neurophysiologists have long recognized in GSWD a unique electrographic and behavioral marker of the genetic predisposition to most types of epilepsy. Interestingly, the subject is still controversial since it has recently been proposed that both classification terms of CAE currently in use: idiopathic and primary generalized, be abandoned - a point of debate. Both issues - underlying mechanisms and focal origin of absence seizures - may be further enlightened by observations in valid animal models.
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Affiliation(s)
- Miguel A Cortez
- Division of Neurology, Neuroscience and Mental Health Program, SickKids Research Institute, Hospital for Sick Children, Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
| | | | - O Carter Snead
- Division of Neurology, Neuroscience and Mental Health Program, SickKids Research Institute, Hospital for Sick Children, Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada.
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Abstract
Despite appropriate antiepileptic drug treatment, approximately one-third of humans and dogs with epilepsy continue experiencing seizures, emphasising the importance for new treatment strategies to improve the quality of life of people or dogs with epilepsy. A 6-month prospective, randomised, double-blinded, placebo-controlled cross-over dietary trial was designed to compare a ketogenic medium-chain TAG diet (MCTD) with a standardised placebo diet in chronically antiepileptic drug-treated dogs with idiopathic epilepsy. Dogs were fed either MCTD or placebo diet for 3 months followed by a subsequent respective switch of diet for a further 3 months. Seizure frequency, clinical and laboratory data were collected and evaluated for twenty-one dogs completing the study. Seizure frequency was significantly lower when dogs were fed the MCTD (2·31/month, 0-9·89/month) in comparison with the placebo diet (2·67/month, 0·33-22·92/month, P=0·020); three dogs achieved seizure freedom, seven additional dogs had ≥50 % reduction in seizure frequency, five had an overall <50 % reduction in seizures (38·87 %, 35·68-43·27 %) and six showed no response. Seizure day frequency were also significantly lower when dogs were fed the MCTD (1·63/month, 0-7·58/month) in comparison with the placebo diet (1·69/month, 0·33-13·82/month, P=0·022). Consumption of the MCTD also resulted in significant elevation of blood β-hydroxybutyrate concentrations in comparison with placebo diet (0·071 (sd 0·035) v. 0·053 (sd 0·028) mmol/l, P=0·028). There were no significant changes in serum concentrations of glucose (P=0·903), phenobarbital (P=0·422), potassium bromide (P=0·404) and weight (P=0·300) between diet groups. In conclusion, the data show antiepileptic properties associated with ketogenic diets and provide evidence for the efficacy of the MCTD used in this study as a therapeutic option for epilepsy treatment.
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Nôga DAMF, Cagni FC, Santos JR, Silva D, Azevedo DLO, Araújo A, Silva RH, Ribeiro AM. Pro- and Anticonvulsant Effects of the Ant Dinoponera quadriceps (Kempf) Venom in Mice. NEOTROPICAL ENTOMOLOGY 2015; 44:410-417. [PMID: 26045053 DOI: 10.1007/s13744-015-0292-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 03/18/2015] [Indexed: 06/04/2023]
Abstract
Epilepsy affects at least 50 million people worldwide, and the available treatment is associated with various side effects. Approximately 20-30% of the patients develop seizures that persist despite careful monitored treatment with antiepileptic drugs. Thus, there is a clear need for the development of new antiepileptic drugs, and the venoms can be an excellent source of probes. In this context, while there are studies on venoms from snakes, scorpions, and spiders, little is known regarding venom from ants. The aim of this study was to investigate the potential pro- and anticonvulsant effects of the venom from the ant Dinoponera quadriceps (Kempf) in Swiss mice. After the injection of the crude venom (DqTx-5, 50, and 500 mg/mL) in the lateral ventricle of mice, we observed a reduction of exploration and grooming behaviors, as well as an increase in immobility duration. In addition, the crude venom induced procursive behavior and tonic-clonic seizures at the highest concentration. Conversely, the preadministration of the denatured venom (AbDq) at the concentration of 2 mg/mL protected the animals against tonic-clonic seizures (66.7%) and death (100%) induced by administration of bicuculline. Taken together, the findings demonstrate that D. quadriceps venom might be potential source of new pro- and anticonvulsants molecules.
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Affiliation(s)
- D A M F Nôga
- Depto de Fisiologia, Univ Federal do Rio Grande do Norte, Natal, RN, Brasil
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42
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Barker-Haliski M, White HS. Glutamatergic Mechanisms Associated with Seizures and Epilepsy. Cold Spring Harb Perspect Med 2015; 5:a022863. [PMID: 26101204 PMCID: PMC4526718 DOI: 10.1101/cshperspect.a022863] [Citation(s) in RCA: 234] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Epilepsy is broadly characterized by aberrant neuronal excitability. Glutamate is the predominant excitatory neurotransmitter in the adult mammalian brain; thus, much of past epilepsy research has attempted to understand the role of glutamate in seizures and epilepsy. Seizures induce elevations in extracellular glutamate, which then contribute to excitotoxic damage. Chronic seizures can alter neuronal and glial expression of glutamate receptors and uptake transporters, further contributing to epileptogenesis. Evidence points to a shared glutamate pathology for epilepsy and other central nervous system (CNS) disorders, including depression, which is often a comorbidity of epilepsy. Therapies that target glutamatergic neurotransmission are available, but many have met with difficulty because of untoward adverse effects. Better understanding of this system has generated novel therapeutic targets that directly and indirectly modulate glutamatergic signaling. Thus, future efforts to manage the epileptic patient with glutamatergic-centric treatments now hold greater potential.
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Affiliation(s)
- Melissa Barker-Haliski
- Anticonvulsant Drug Development Program, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah 84108
| | - H Steve White
- Anticonvulsant Drug Development Program, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah 84108
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Barker-Haliski ML, Friedman D, French JA, White HS. Disease Modification in Epilepsy: From Animal Models to Clinical Applications. Drugs 2015; 75:749-67. [DOI: 10.1007/s40265-015-0395-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Depaulis A, Hamelin S. Animal models for mesiotemporal lobe epilepsy: The end of a misunderstanding? Rev Neurol (Paris) 2015; 171:217-26. [DOI: 10.1016/j.neurol.2015.01.558] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/20/2015] [Indexed: 01/24/2023]
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Li X, Zhang M, Xiang C, Li BC, Li P. Antiepileptic C21 steroids from the roots of Cynanchum otophyllum. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2015; 17:724-732. [PMID: 25579837 DOI: 10.1080/10286020.2014.1001380] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In order to discover more natural products possessing potentially antiepileptic activities, three C21 steroids, including a new one, characterized as caudatin-3-O-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside (1), and two known analogs, otophylloside B (2) and caudatin-3-O-β-D-oleandropyranosyl-(1 → 4)-β-D-oleandropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside (3), were isolated from the chloroform extract of the roots of Cynanchum otophyllum and evaluated for their antiepileptic activities by pentylenetrazole (PTZ)-induced zebrafish larval locomotor assay. The results showed that all of them had marked activities of suppressing PTZ-induced seizure behaviors in larval zebrafish at the dose of 10 μg/ml.
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Affiliation(s)
- Xiang Li
- a Faculty of Life Science and Technology, Kunming University of Science and Technology , Kunming 650500 , China
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Saha L, Bhandari S, Bhatia A, Banerjee D, Chakrabarti A. Anti-kindling Effect of Bezafibrate, a Peroxisome Proliferator-activated Receptors Alpha Agonist, in Pentylenetetrazole Induced Kindling Seizure Model. J Epilepsy Res 2014; 4:45-54. [PMID: 25625088 PMCID: PMC4295053 DOI: 10.14581/jer.14011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 11/17/2014] [Indexed: 12/25/2022] Open
Abstract
Background and Purpose: Studies in the animals suggested that Peroxisome proliferators activated receptors (PPARs) may be involved in seizure control and selective agonists of PPAR α or PPAR γ raise seizure thresholds. The present study was contemplated with the aim of evaluating the anti kindling effects and the mechanism of bezafibrate, a Peroxisome proliferator-activated receptors α (PPAR-α) agonist in pentylenetetrazole (PTZ) induced kindling model of seizures in rats. Methods: In a PTZ kindled Wistar rat model, different doses of bezafibrate (100 mg/kg, 200 mg/kg and 300 mg/kg) were administered intraperitoneally 30 minutes before the PTZ injection. The PTZ injection was given on alternate day till the animal became fully kindled or till 10 weeks. The parameters measured were the latency to develop kindling and incidence of kindling, histopathological study of hippocampus, hippocampal lipid peroxidation studies, serum neuron specific enolase, and hippocampal DNA fragmentation study. Results: In this study, bezafibrate significantly reduced the incidence of kindling in PTZ treated rats and exhibited a marked prolongation in the latencies to seizures. In the present study bezafibrate decreased the thiobarbituric acid-reactive substance i.e. Malondialdehyde levels, increased the reduced glutathione levels, catalase and superoxide dismutase activity in the brain. This added to its additional neuroprotective effects. Bezafibrate also reduced the neuronal damage and apoptosis in hippocampal area of the brain. Therefore bezafibrate exerted anticonvulsant properties in PTZ induced kindling model in rats. Conclusions: These findings may provide insights into the understanding of the mechanism of bezafibrate as an anti kindling agent and could offer a useful support to the basic antiepileptic therapy in preventing the development of PTZ induced seizures, suggesting its potential for therapeutic applications in temporal lobe epilepsy.
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Affiliation(s)
- Lekha Saha
- Department of Pharmacology, Postgraduate Institute of Medical Education & Research, Sector 12, Chandigarh
| | - Swati Bhandari
- Department of Pharmacology, Postgraduate Institute of Medical Education & Research, Sector 12, Chandigarh
| | - Alka Bhatia
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute Of Medical Education & Research, Sector 12, Chandigarh, India
| | - Dibyajyoti Banerjee
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute Of Medical Education & Research, Sector 12, Chandigarh, India
| | - Amitava Chakrabarti
- Department of Pharmacology, Postgraduate Institute of Medical Education & Research, Sector 12, Chandigarh
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Lima PAD, Sampaio LPDB, Damasceno NRT. Neurobiochemical mechanisms of a ketogenic diet in refractory epilepsy. Clinics (Sao Paulo) 2014; 69:699-705. [PMID: 25518023 PMCID: PMC4221309 DOI: 10.6061/clinics/2014(10)09] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 05/27/2014] [Indexed: 12/14/2022] Open
Abstract
A ketogenic diet is an important therapy used in the control of drug-refractory seizures. Many studies have shown that children and adolescents following ketogenic diets exhibit an over 50% reduction in seizure frequency, which is considered to be clinically relevant. These benefits are based on a diet containing high fat (approximately 90% fat) for 24 months. This dietary model was proposed in the 1920s and has produced variable clinical responses. Previous studies have shown that the mechanisms underlying seizure control involve ketone bodies, which are produced by fatty acid oxidation. Although the pathways involved in the ketogenic diet are not entirely clear, the main effects of the production of ketone bodies appear to be neurotransmitter modulation and antioxidant effects on the brain. This review highlights the impacts of the ketogenic diet on the modulation of neurotransmitters, levels of biogenic monoamines and protective antioxidant mechanisms of neurons. In addition, future perspectives are proposed.
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Affiliation(s)
- Patricia Azevedo de Lima
- Post-Graduate Program in Applied Human Nutrition, Universidade de São Paulo, São Paulo, SP, Brazil
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48
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Merbl Y, Sommer A, Chai O, Aroch I, Zimmerman G, Friedman A, Soreq H, Shamir M. Tumor necrosis factor-α and interleukin-6 concentrations in cerebrospinal fluid of dogs after seizures. J Vet Intern Med 2014; 28:1775-81. [PMID: 25308784 PMCID: PMC4895630 DOI: 10.1111/jvim.12462] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 06/06/2014] [Accepted: 08/21/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Idiopathic and acquired epilepsy are common in dogs. Up to 30% of these dogs are refractory to pharmacological treatment. Accumulating experimental evidence indicates that brain immune response and presence of inflammatory mediators decrease the threshold for individual seizures and contribute to epileptogenesis. HYPOTHESIS Dogs with seizures have higher cerebrospinal interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations compared to dogs with no seizures. METHODS A prospective double blinded study; cerebrospinal fluid (CSF) and serum IL-6, TNF-α and total protein (TP) concentrations were measured by a blinded investigator for the study group and CSF IL-6 and TNF-α levels and TP concentrations were measured in the control group (CG). ANIMALS Dogs presented with seizures that had enough CSF collected to allow analysis were included in the study group. Twelve apparently healthy, quarantined, stray dogs served as control (CG). RESULTS Cerebrospinal fluid TNF-α and IL-6 concentrations were significantly higher (P = .011, P = .039) in dogs with seizures (0 ± 70.66, 0.65 ± 10.93 pg/mL) compared to the CG (0 ± 19, 0.73 ± 0.55 pg/mL). When assessing cytokine concentrations of specifically the idiopathic epilepsy (IE) dogs compared to the CG, only TNF-α concentrations (8.66 ± 62, 0 ± 19 pg/mL) were significantly higher (P = .01). CSF TP concentrations were not significantly higher in the study dogs compared to the CG. CONCLUSIONS AND CLINICAL IMPORTANCE Higher TNF-α and IL-6 concentration in the CSF of dogs with naturally occurring seizures. The higher supports the hypothesis that inflammatory processes through certain mediators play a role in the pathogenesis of seizures in dogs.
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Affiliation(s)
- Y. Merbl
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - A. Sommer
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - O. Chai
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - I. Aroch
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - G. Zimmerman
- Edmond and Lily Safra Center of Brain ScienceHebrew University of JerusalemJerusalemIsrael
| | - A. Friedman
- Department of Life SciencesBen‐Gurion University of the NegevBeer ShevaIsrael
| | - H. Soreq
- Edmond and Lily Safra Center of Brain ScienceHebrew University of JerusalemJerusalemIsrael
- Department of Biological ChemistryAlexander Silberman Institute of Life SciencesHebrew University of JerusalemJerusalemIsrael
| | - M.H. Shamir
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
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Hippocampal low-frequency stimulation increased SV2A expression and inhibited the seizure degree in pharmacoresistant amygdala-kindling epileptic rats. Epilepsy Res 2014; 108:1483-91. [DOI: 10.1016/j.eplepsyres.2014.07.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 07/21/2014] [Accepted: 07/27/2014] [Indexed: 11/19/2022]
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50
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García-Cabrero AM, Sánchez-Elexpuru G, Serratosa JM, Sánchez MP. Enhanced sensitivity of laforin- and malin-deficient mice to the convulsant agent pentylenetetrazole. Front Neurosci 2014; 8:291. [PMID: 25309313 PMCID: PMC4162417 DOI: 10.3389/fnins.2014.00291] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 08/27/2014] [Indexed: 12/04/2022] Open
Abstract
Lafora disease is a rare form of inherited progressive myoclonus epilepsy caused by mutations in the EPM2A gene encoding laforin, or in the EPM2B gene, which encodes malin. It is characterized by the presence of polyglucosan inclusion bodies (Lafora bodies) in brain and other tissues. Genetically engineered mice lacking expression of either the laforin (Epm2a(-/-) ) or malin (Epm2b(-/-) ) genes display a number of neurological and behavioral abnormalities that resemble those found in patients suffering from Lafora disease; of these, both Epm2a(-/-) and Epm2b(-/-) mice have shown altered motor activity, impaired motor coordination, episodic memory deficits, and different degrees of spontaneous epileptic activity. In this study, we analyze the sensitivity of Epm2a(-/-) and Epm2b(-/-) mice to the convulsant drug pentylenetetrazol (PTZ), an antagonist of the γ-aminobutyric acid type A (GABAA) receptor, commonly used to induce epileptic tonic-clonic seizures in laboratory animals. PTZ-induced epileptic activity, including myoclonic jerks and tonic-clonic seizures, was analyzed in 2 age groups of mice comprising representative samples of young adult and aged mice, after administration of PTZ at sub-convulsive and convulsive doses. Epm2a(-/-) and Epm2b(-/-) mice showed a lower convulsive threshold after PTZ injections at sub-convulsive doses. A lower convulsive threshold and shorter latencies to develop epileptic seizures were observed after PTZ injections at convulsive doses. Different patterns of generalized seizures and of discharges were observed in Epm2a(-/-) and Epm2b(-/-) mice. Epm2a(-/-) and Epm2b(-/-) mice present an increased sensitivity to the convulsant agent PTZ that may reflect different degrees of increased GABAA receptor-mediated hyperexcitability.
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Affiliation(s)
- Ana M. García-Cabrero
- Laboratory of Neurology, IIS-Fundación Jiménez Díaz, Universidad Autónoma de MadridMadrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades RarasMadrid, Spain
| | - Gentzane Sánchez-Elexpuru
- Laboratory of Neurology, IIS-Fundación Jiménez Díaz, Universidad Autónoma de MadridMadrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades RarasMadrid, Spain
| | - José M. Serratosa
- Laboratory of Neurology, IIS-Fundación Jiménez Díaz, Universidad Autónoma de MadridMadrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades RarasMadrid, Spain
| | - Marina P. Sánchez
- Laboratory of Neurology, IIS-Fundación Jiménez Díaz, Universidad Autónoma de MadridMadrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades RarasMadrid, Spain
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