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Næsgaard JAR, Gjerstad L, Heuser K, Taubøll E. Biological rhythms and epilepsy treatment. Front Neurol 2023; 14:1153975. [PMID: 37638185 PMCID: PMC10453794 DOI: 10.3389/fneur.2023.1153975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 07/31/2023] [Indexed: 08/29/2023] Open
Abstract
Approximately one-third of patients with epilepsy are drug-refractory, necessitating novel treatment approaches. Chronopharmacology, which adjusts pharmacological treatment to physiological variations in seizure susceptibility and drug responsiveness, offers a promising strategy to enhance efficacy and tolerance. This narrative review provides an overview of the biological foundations for rhythms in seizure activity, clinical implications of seizure patterns through case reports, and the potential of chronopharmacological strategies to improve treatment. Biological rhythms, including circadian and infradian rhythms, play an important role in epilepsy. Understanding seizure patterns may help individualize treatment decisions and optimize therapeutic outcomes. Altering drug concentrations based on seizure risk periods, adjusting administration times, and exploring hormone therapy are potential strategies. Large-scale randomized controlled trials are needed to evaluate the efficacy and safety of differential and intermittent treatment approaches. By tailoring treatment to individual seizure patterns and pharmacological properties, chronopharmacology offers a personalized approach to improve outcomes in patients with epilepsy.
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Affiliation(s)
| | - Leif Gjerstad
- Faculty of Medicine, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Neurology, Division of Clinical Neuroscience, ERGO – Epilepsy Research Group of Oslo, Oslo University Hospital, Oslo, Norway
| | - Kjell Heuser
- Department of Neurology, Division of Clinical Neuroscience, ERGO – Epilepsy Research Group of Oslo, Oslo University Hospital, Oslo, Norway
| | - Erik Taubøll
- Faculty of Medicine, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Neurology, Division of Clinical Neuroscience, ERGO – Epilepsy Research Group of Oslo, Oslo University Hospital, Oslo, Norway
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Nobili L, Frauscher B, Eriksson S, Gibbs SA, Halasz P, Lambert I, Manni R, Peter-Derex L, Proserpio P, Provini F, de Weerd A, Parrino L. Sleep and epilepsy: A snapshot of knowledge and future research lines. J Sleep Res 2022; 31:e13622. [PMID: 35487880 PMCID: PMC9540671 DOI: 10.1111/jsr.13622] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 04/12/2022] [Indexed: 11/29/2022]
Abstract
Sleep and epilepsy have a reciprocal relationship, and have been recognized as bedfellows since antiquity. However, research on this topic has made a big step forward only in recent years. In this narrative review we summarize the most stimulating discoveries and insights reached by the "European school." In particular, different aspects concerning the sleep-epilepsy interactions are analysed: (a) the effects of sleep on epilepsy; (b) the effects of epilepsy on sleep structure; (c) the relationship between epilepsy, sleep and epileptogenesis; (d) the impact of epileptic activity during sleep on cognition; (e) the relationship between epilepsy and the circadian rhythm; (f) the history and features of sleep hypermotor epilepsy and its differential diagnosis; (g) the relationship between epilepsy and sleep disorders.
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Affiliation(s)
- Lino Nobili
- Child Neuropsychiatric Unit, Istituto G. Gaslini, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, Genoa, Italy
| | - Birgit Frauscher
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Sofia Eriksson
- Department of Clinical and Experiential Epilepsy, UCL Institute of Neurology, University College London, London, UK
| | - Steve Alex Gibbs
- Department of Neurosciences, Center for Advanced Research in Sleep Medicine, Sacred Heart Hospital, University of Montreal, Montreal, Quebec, Canada
| | - Peter Halasz
- Szentagothai János School of Ph.D Studies, Clinical Neurosciences, Semmelweis University, Budapest, Hungary
| | - Isabelle Lambert
- Aix Marseille Univ, Inserm, INS, Institut de Neurosciences des Systèmes, Marseille, France.,APHM, Timone Hospital, Clinical Neurophysiology, Marseille, France
| | - Raffaele Manni
- Unit of Sleep Medicine and Epilepsy, IRCCS Mondino Foundation, Pavia, Italy
| | - Laure Peter-Derex
- Center for Sleep Medicine and Respiratory Diseases, Lyon University Hospital, Lyon 1 University, Lyon, France.,Lyon Neuroscience Research Center, CNRS UMR 5292/INSERM U1028, Lyon, France
| | - Paola Proserpio
- Department of Neuroscience, Sleep Medicine Centre, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Federica Provini
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy.,IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Al de Weerd
- Stichting Epilepsie Instellingen Nederland, Zwolle, Netherlands
| | - Liborio Parrino
- Department of General and Specialized Medicine, Sleep Disorders Center, University Hospital of Parma, Parma, Italy
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Romero A, Ramos E, López-Muñoz F, Gil-Martín E, Escames G, Reiter RJ. Coronavirus Disease 2019 (COVID-19) and Its Neuroinvasive Capacity: Is It Time for Melatonin? Cell Mol Neurobiol 2022; 42:489-500. [PMID: 32772307 PMCID: PMC7415199 DOI: 10.1007/s10571-020-00938-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/05/2020] [Indexed: 01/08/2023]
Abstract
The world faces an exceptional new public health concern caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), subsequently termed the coronavirus disease 2019 (COVID-19) by the World Health Organization (WHO). Although the clinical symptoms mostly have been characterized, the scientific community still doesn´t know how SARS-CoV-2 successfully reaches and spreads throughout the central nervous system (CNS) inducing brain damage. The recent detection of SARS-CoV-2 in the cerebrospinal fluid (CSF) and in frontal lobe sections from postmortem examination has confirmed the presence of the virus in neural tissue. This finding reveals a new direction in the search for a neurotherapeutic strategy in the COVID-19 patients with underlying diseases. Here, we discuss the COVID-19 outbreak in a neuroinvasiveness context and suggest the therapeutic use of high doses of melatonin, which may favorably modulate the immune response and neuroinflammation caused by SARS-CoV-2. However, clinical trials elucidating the efficacy of melatonin in the prevention and clinical management in the COVID-19 patients should be actively encouraged.
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Affiliation(s)
- Alejandro Romero
- grid.4795.f0000 0001 2157 7667Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Complutense University of Madrid, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - Eva Ramos
- grid.4795.f0000 0001 2157 7667Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Complutense University of Madrid, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - Francisco López-Muñoz
- grid.449750.b0000 0004 1769 4416Faculty of Health Sciences, University Camilo José Cela, C/ Castillo de Alarcón 49, 28692 Villanueva de la Cañada, Madrid, Spain ,grid.144756.50000 0001 1945 5329Neuropsychopharmacology Unit, Hospital 12 de Octubre Research Institute (i+12), Avda. Córdoba, s/n, 28041 Madrid, Spain ,grid.410919.40000 0001 2152 2367Portucalense Institute of Neuropsychology and Cognitive and Behavioural Neurosciences (INPP), Portucalense University, R. Dr. António Bernardino de Almeida 541, 4200-072 Porto, Portugal ,grid.413448.e0000 0000 9314 1427Thematic Network for Cooperative Health Research (RETICS), Addictive Disorders Network, Health Institute Carlos III, MICINN and FEDER, Madrid, Spain
| | - Emilio Gil-Martín
- grid.6312.60000 0001 2097 6738Nutrition and Food Science Group, Department of Biochemistry, Genetics and Immunology, Faculty of Biology, University of Vigo, 36310 Vigo, Spain
| | - Germaine Escames
- grid.4489.10000000121678994Biomedical Research Center, Health Sciences Technology Park, University of Granada, 18016 Granada, Spain ,grid.4489.10000000121678994Department of Physiology, University of Granada, 18016 Granada, Spain ,grid.507088.2Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable, Instituto de Investigación Biosanitaria CIBERFES, IBS. Granada, Granada Hospital Complex, 18016 Granada, Spain
| | - Russel J. Reiter
- grid.267309.90000 0001 0629 5880Department of Cellular and Structural Biology, University of Texas Health Science at San Antonio, San Antonio, TX 78229 USA
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Zhong D, Luo S, Zheng L, Zhang Y, Jin R. Epilepsy Occurrence and Circadian Rhythm: A Bibliometrics Study and Visualization Analysis via CiteSpace. Front Neurol 2020; 11:984. [PMID: 33250835 PMCID: PMC7674827 DOI: 10.3389/fneur.2020.00984] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 07/28/2020] [Indexed: 02/05/2023] Open
Abstract
Objective: This study aimed to review the research status and to demonstrate the hot spots and frontiers of epilepsy and circadian rhythm via CiteSpace. Method: We searched Web of Science (WoS) for studies related to epilepsy and circadian rhythm from inception to 2020. CiteSpace was used to generate network maps about the collaborations between authors, countries, and institutions and reveal hot spots and frontiers of epilepsy and circadian rhythm. Results: A total of 704 studies related to epilepsy and circadian rhythm from the WoS were retrieved. Sanchez-Vazquez FJ was the most prolific author (17 articles). The USA and University of Murcia were the leading country and institution in this field with 219 and 22 publications, respectively. There were active collaborations among the authors, countries, and institutions. Hot topics focused on the interaction between epilepsy and circadian rhythm, as well as possible novel treatments. Conclusions: Based on the results of CiteSpace, the current study suggested active cooperation between authors, countries, and institutions. Major ongoing research trends include the circadian rhythm of epilepsy based on different epileptic focus and the interaction between epilepsy and circadian rhythm, especially through melatonin, sleep–wake cycles, and clock genes, which may implicate possible treatments (such as chronotherapy, neural stem cells transplantation) for epilepsy in the future.
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Affiliation(s)
- Dongling Zhong
- Department of Periodical Press and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China.,School of Health Preservation and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Shanxia Luo
- Mental Health Center, West China University Hospital, Sichuan University, Chengdu, China
| | - Linli Zheng
- Mental Health Center, West China University Hospital, Sichuan University, Chengdu, China
| | - Yonggang Zhang
- Department of Periodical Press and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Rongjiang Jin
- School of Health Preservation and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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Jin B, Aung T, Geng Y, Wang S. Epilepsy and Its Interaction With Sleep and Circadian Rhythm. Front Neurol 2020; 11:327. [PMID: 32457690 PMCID: PMC7225332 DOI: 10.3389/fneur.2020.00327] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 04/03/2020] [Indexed: 12/12/2022] Open
Abstract
Growing evidence shows the bidirectional interactions between sleep, circadian rhythm, and epilepsy. Comprehending how these interact with each other may help to advance our understanding of the pathophysiology of epilepsy and develop new treatment strategies to improve seizure control by reducing the medication side effects and the risks associated with seizures. In this review, we present the overview of different temporal patterns of interictal epileptiform discharges and epileptic seizures over a period of 24 consecutive hours. Furthermore, we discuss the underlying mechanism of the core-clock gene in periodic seizure occurrences. Finally, we outline the role of circadian patterns of seizures on seizure forecasting models and its implication for chronotherapy in epilepsy.
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Affiliation(s)
- Bo Jin
- Department of Neurology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Thandar Aung
- Barrow Neurological Institute, Epilepsy Center, Phoenix, AZ, United States
| | - Yu Geng
- Department of Neurology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Shuang Wang
- Department of Neurology, Epilepsy Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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Adverse Events Associated with Melatonin for the Treatment of Primary or Secondary Sleep Disorders: A Systematic Review. CNS Drugs 2019; 33:1167-1186. [PMID: 31722088 DOI: 10.1007/s40263-019-00680-w] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Melatonin is widely available either on prescription for the treatment of sleep disorders or as an over-the-counter dietary supplement. Melatonin has also recently been licensed in the UK for the short-term treatment of jetlag. Little is known about the potential for adverse events (AEs), in particular AEs resulting from long-term use. Concern has been raised over the possible risks of exposure in certain populations including pre-adolescent children and patients with epilepsy or asthma. OBJECTIVES The aim of this systematic review was to assess the evidence for AEs associated with short-term and longer-term melatonin treatment for sleep disorders. METHODS A literature search of the PubMed/Medline database and Google Scholar was conducted to identify randomised, placebo-controlled trials (RCTs) of exogenous melatonin administered for primary or secondary sleep disorders. Studies were included if they reported on both the types and frequencies of AEs. Studies of pre-term infants, studies of < 1 week in duration or involving single doses of melatonin and studies in languages other than English were excluded. Findings from open-label studies that raised concerns relating to AE reports in patients were also examined. Studies were assessed for quality of reporting against the Consolidated Standards of Reporting Trials (CONSORT) checklist and for risk of bias against the Cochrane Collaboration risk-of-bias criteria. RESULTS 37 RCTs met criteria for inclusion. Daily melatonin doses ranged from 0.15 mg to 12 mg. Subjects were monitored for up to 29 weeks, but most studies were of much shorter duration (4 weeks or less). The most frequently reported AEs were daytime sleepiness (1.66%), headache (0.74%), other sleep-related AEs (0.74%), dizziness (0.74%) and hypothermia (0.62%). Very few AEs considered to be serious or of clinical significance were reported. These included agitation, fatigue, mood swings, nightmares, skin irritation and palpitations. Most AEs either resolved spontaneously within a few days with no adjustment in melatonin, or immediately upon withdrawal of treatment. Melatonin was generally regarded as safe and well tolerated. Many studies predated publication of the CONSORT checklist and consequently did not conform closely to the guidelines. Similarly, only eight studies were judged 'good' overall with respect to the Cochrane risk-of-bias criteria. Of the remaining papers, 16 were considered 'fair' and 13 'poor' but publication of almost half of the papers preceded that of the earliest version of the guidelines. CONCLUSION Few, generally mild to moderate, AEs were associated with exogenous melatonin. No AEs that were life threatening or of major clinical significance were identified. The scarcity of evidence from long-term RCTs, however, limits the conclusions regarding the safety of continuous melatonin therapy over extended periods. There are insufficient robust data to allow a meaningful appraisal of concerns that melatonin may result in more clinically significant adverse effects in potentially at-risk populations. Future studies should be designed to comply with appropriate quality standards for RCTs, which most past studies have not.
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Chen X, Xi Z, Liang H, Sun Y, Zhong Z, Wang B, Bian L, Sun Q. Melatonin Prevents Mice Cortical Astrocytes From Hemin-Induced Toxicity Through Activating PKCα/Nrf2/HO-1 Signaling in vitro. Front Neurosci 2019; 13:760. [PMID: 31404262 PMCID: PMC6669962 DOI: 10.3389/fnins.2019.00760] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/09/2019] [Indexed: 12/30/2022] Open
Abstract
Secondary injuries mediated by oxidative stress lead to deterioration of neurological functions after intracerebral hemorrhage (ICH). Cortical astrocytes are among the most important cells in the central nervous system (CNS), and play key roles in maintaining redox homeostasis by providing oxidative stress defense. Hemin is a product of hemoglobin degradation, which has strong toxicity and can induce reactive oxygen species (ROS). Melatonin (Mel) and its metabolites are well tolerated without toxicity, prevent tissue damage as well as effectively assist in scavenging free radicals. We evaluated the hemin neurotoxicity to astrocytes and the resistance of Mel-treated astrocytes to hemin neurotoxicity. And we found Mel induced PKCα phosphorylation (p-PKC), nuclear translocation of Nrf2 in astrocytes, and upregulation of HO-1, which contributed to the reduction of ROS accumulation and cell apoptosis. Nrf2 and HO1 protein expression upregulated by Mel were decreased after administration of PKC inhibitor, Ro 31-8220 (Ro 31). Luzindole (Luz), a melatonin receptor inhibitor, suppressed p-PKCα, HO-1, and Nrf2 expression upregulated by Mel and increased cell apoptosis rate. The upregulation of HO-1 induced by Mel was depressed by knocking down Nrf2 expression by siRNA, which also decreased the resistance of astrocytes to toxicity of hemin. Mel activates astrocytes through PKCα/Nrf2/HO-1 signaling pathway to acquire resistance to toxicity of hemin and resist from oxidative stress and apoptosis. The positive effect of Mel on PKCα/Nrf2/HO-1 signaling pathway may become a new target for neuroprotection after intracerebral hemorrhage.
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Affiliation(s)
- Xiao Chen
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhiyu Xi
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Huaibin Liang
- Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yuhao Sun
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhihong Zhong
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Baofeng Wang
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Liuguan Bian
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qingfang Sun
- Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Department of Neurosurgery, Ruijin Hospital Luwan Branch, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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Wang DD, Jin MF, Zhao DJ, Ni H. Reduction of Mitophagy-Related Oxidative Stress and Preservation of Mitochondria Function Using Melatonin Therapy in an HT22 Hippocampal Neuronal Cell Model of Glutamate-Induced Excitotoxicity. Front Endocrinol (Lausanne) 2019; 10:550. [PMID: 31440210 PMCID: PMC6694460 DOI: 10.3389/fendo.2019.00550] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 07/23/2019] [Indexed: 12/26/2022] Open
Abstract
Recent evidence indicates that autophagy-mediated mitochondrial homeostasis is crucial for oxidative stress-related brain damage and repair. The highest concentration of melatonin is in the mitochondria of cells, and melatonin exhibits well-known antioxidant properties. We investigated the impact and mechanism involved in mitochondrial function and the mitochondrial oxidative stress/autophagy regulator parameters of glutamate cytotoxicity in mouse HT22 hippocampal neurons. We tested the hypothesis that melatonin confers neuroprotective effects via protecting against mitochondrial impairment and mitophagy. Cells were divided into four groups: the control group, melatonin alone group, glutamate injury group, and melatonin pretreatment group. We found that glutamate induced significant changes in mitochondrial function/oxidative stress-related parameters. Leptin administration preserved mitochondrial function, and this effect was associated with increased superoxide dismutase, glutathione (GSH), and mitochondrial membrane potential and decreased GSSG (oxidized glutathione) and mitochondrial reactive oxygen species. Melatonin significantly reduced the fluorescence intensity of mitophagy via the Beclin-1/Bcl-2 pathway, which involves Beclin-1 and Bcl-2 proteins. The mitophagy inhibitor CsA corrected these glutamate-induce changes, as measured by the fluorescence intensity of Mitophagy-Tracker Red CMXROS, mitochondrial ROS, and mitochondrial membrane potential changes. These findings indicate that melatonin exerts neuroprotective effects against glutamate-induced excitotoxicity by reducing mitophagy-related oxidative stress and maintaining mitochondrial function.
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Holden K, Hartman AL. d-Leucine: Evaluation in an epilepsy model. Epilepsy Behav 2018; 78:202-209. [PMID: 29122492 PMCID: PMC5756680 DOI: 10.1016/j.yebeh.2017.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 08/25/2017] [Accepted: 09/05/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND Current medicines do not provide sufficient seizure control for nearly one-third of patients with epilepsy. New options are needed to address this treatment gap. We recently found that the atypical amino acid d-leucine protected against acutely-induced seizures in mice, but its effect in chronic seizures has not been explored. We hypothesized that d-leucine would protect against spontaneous recurrent seizures. We also investigated whether mice lacking a previously-described d-leucine receptor (Tas1R2/R3) would be protected against acutely-induced seizures. METHODS Male FVB/NJ mice were subjected to kainic acid-induced status epilepticus and monitored by video-electroencephalography (EEG) (surgically implanted electrodes) for 4weeks before, during, and after treatment with d-leucine. Tas1R2/R3 knockout mice and controls underwent the maximal electroshock threshold (MES-T) and 6-Hz tests. RESULTS There was no difference in number of calendar days with seizures or seizure frequency with d-leucine treatment. In an exploratory analysis, mice treated with d-leucine had a lower number of dark cycles with seizures. Tas1R2/R3 knockout mice had elevated seizure thresholds in the MES-T test but not the 6-Hz test. CONCLUSIONS d-Leucine treatment was ineffective against chronic seizures after kainic acid-induced status epilepticus, but there was some efficacy during the dark cycle. Because d-leucine is highly concentrated in the pineal gland, these data suggest that d-leucine may be useful as a tool for studying circadian patterns in epilepsy. Deletion of the Tas1R2/R3 receptor protected against seizures in the MES-T test and, therefore, may be a novel target for treating seizures.
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Affiliation(s)
- Kylie Holden
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Adam L Hartman
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, United States; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States.
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