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Klein P, Kaminski RM, Koepp M, Löscher W. New epilepsy therapies in development. Nat Rev Drug Discov 2024:10.1038/s41573-024-00981-w. [PMID: 39039153 DOI: 10.1038/s41573-024-00981-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2024] [Indexed: 07/24/2024]
Abstract
Epilepsy is a common brain disorder, characterized by spontaneous recurrent seizures, with associated neuropsychiatric and cognitive comorbidities and increased mortality. Although people at risk can often be identified, interventions to prevent the development of the disorder are not available. Moreover, in at least 30% of patients, epilepsy cannot be controlled by current antiseizure medications (ASMs). As a result of considerable progress in epilepsy genetics and the development of novel disease models, drug screening technologies and innovative therapeutic modalities over the past 10 years, more than 200 novel epilepsy therapies are currently in the preclinical or clinical pipeline, including many treatments that act by new mechanisms. Assisted by diagnostic and predictive biomarkers, the treatment of epilepsy is undergoing paradigm shifts from symptom-only ASMs to disease prevention, and from broad trial-and-error treatments for seizures in general to mechanism-based treatments for specific epilepsy syndromes. In this Review, we assess recent progress in ASM development and outline future directions for the development of new therapies for the treatment and prevention of epilepsy.
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Affiliation(s)
- Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, MD, USA.
| | | | - Matthias Koepp
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Wolfgang Löscher
- Translational Neuropharmacology Lab., NIFE, Department of Experimental Otology of the ENT Clinics, Hannover Medical School, Hannover, Germany.
- Center for Systems Neuroscience, Hannover, Germany.
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Cho S, Soumare F, Mumford SL, Rosas PC, Abrieva Z, Davis JM, Hamidovic A. Peripheral Blood Mononuclear Cell Expression of Cation-Chloride Cotransporter (CCC) Genes in Premenstrual Dysphoric Disorder (PMDD) across the Menstrual Cycle-A Preliminary Study. BIOLOGY 2024; 13:377. [PMID: 38927257 PMCID: PMC11201072 DOI: 10.3390/biology13060377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/09/2024] [Accepted: 05/23/2024] [Indexed: 06/28/2024]
Abstract
Premenstrual Dysphoric Disorder (PMDD) is a psychiatric condition characterized by debilitating affective symptomatology in the luteal phase of the menstrual cycle. Based on the previous reports that PMDD may be related to GABAergic cellular dysfunction(s), we assessed whether cation-chloride cotransporter (CCC) gene expression across the menstrual cycle is altered in PMDD. As there are limitations in accessing the human CNS to study CCC-encoding genes, we utilized peripheral blood mononuclear cells (PBMCs) as an alternative model. We first sought to replicate previous reports characterizing CCC gene expression patterns in PBMCs of reproductive age women. We subsequently investigated potential distinct CCC mRNA expression patterns in women with PMDD. We collected blood samples across 8 menstrual cycle visits for PBMC separation/RNA extraction to study mRNA expression of four KCCs (KCC1, KCC2, KCC3, KCC4) and two NKCCs (NKCC1, NKCC2) cotransporters. We mostly replicated the earlier gene expression pattern findings, and found that the expression levels of KCC1 were significantly downregulated during the mid-follicular and periovulatory subphases of the menstrual cycle in women with PMDD. The present study shows that PBMCs is a valid model for studying GABAergic mechanisms underlying PMDD.
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Affiliation(s)
- Soojeong Cho
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA; (S.C.); (F.S.); (P.C.R.)
| | - Fatimata Soumare
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA; (S.C.); (F.S.); (P.C.R.)
| | - Sunni L. Mumford
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA;
| | - Paola C. Rosas
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA; (S.C.); (F.S.); (P.C.R.)
| | - Zarema Abrieva
- Genomics Research Core, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA;
| | - John M. Davis
- Department of Psychiatry, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA;
| | - Ajna Hamidovic
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA; (S.C.); (F.S.); (P.C.R.)
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Zhu S, Shi J, Zhang Y, Chen X, Shi T, Li L. Combination administration of alprazolam and N-Ethylmaleimide synergistically enhances sleep behaviors in mice with no potential CNS side effects. PeerJ 2024; 12:e17342. [PMID: 38737745 PMCID: PMC11086308 DOI: 10.7717/peerj.17342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 04/15/2024] [Indexed: 05/14/2024] Open
Abstract
Background N-Ethylmaleimide (NEM), an agonist of the potassium chloride cotransporters 2 (KCC2) receptor, has been correlated with neurosuppressive outcomes, including decreased pain perception and the prevention of epileptic seizures. Nevertheless, its relationship with sleep-inducing effects remains unreported. Objective The present study aimed to investigate the potential enhancement of NEM on the sleep-inducing properties of alprazolam (Alp). Methods The test of the righting reflex was used to identify the appropriate concentrations of Alp and NEM for inducing sleep-promoting effects in mice. Total sleep duration and sleep quality were evaluated through EEG/EMG analysis. The neural mechanism underlying the sleep-promoting effect was examined through c-fos immunoreactivity in the brain using immunofluorescence. Furthermore, potential CNS-side effects of the combination Alp and NEM were assessed using LABORAS automated home-cage behavioral phenotyping. Results Combination administration of Alp (1.84 mg/kg) and NEM (1.0 mg/kg) significantly decreased sleep latency and increased sleep duration in comparison to administering 1.84 mg/kg Alp alone. This effect was characterized by a notable increase in REM duration. The findings from c-fos immunoreactivity indicated that NEM significantly suppressed neuron activation in brain regions associated with wakefulness. Additionally, combination administration of Alp and NEM showed no effects on mouse neural behaviors during automated home cage monitoring. Conclusions This study is the first to propose and demonstrate a combination therapy involving Alp and NEM that not only enhances the hypnotic effect but also mitigates potential CNS side effects, suggesting its potential application in treating insomnia.
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Affiliation(s)
- Siqing Zhu
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Jingjing Shi
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Yi Zhang
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Xuejun Chen
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Tong Shi
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
| | - Liqin Li
- State Key Laboratory of NBC Protection for Civilian, Beijing, China
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Cho N, Kontou G, Smalley JL, Bope C, Dengler J, Montrose K, Deeb TZ, Brandon NJ, Yamamoto T, Davies PA, Giamas G, Moss SJ. The brain-specific kinase LMTK3 regulates neuronal excitability by decreasing KCC2-dependent neuronal Cl - extrusion. iScience 2024; 27:109512. [PMID: 38715938 PMCID: PMC11075064 DOI: 10.1016/j.isci.2024.109512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/20/2023] [Accepted: 03/13/2024] [Indexed: 05/13/2024] Open
Abstract
LMTK3 is a brain-specific transmembrane serine/threonine protein kinase that acts as a scaffold for protein phosphatase-1 (PP1). Although LMKT3 has been identified as a risk factor for autism and epilepsy, its physiological significance is unknown. Here, we demonstrate that LMTK3 copurifies and binds to KCC2, a neuron-specific K+/Cl- transporter. KCC2 activity is essential for Cl--mediated hyperpolarizing GABAAR receptor currents, the unitary events that underpin fast synaptic inhibition. LMTK3 acts to promote the association of KCC2 with PP1 to promote the dephosphorylation of S940 within its C-terminal cytoplasmic domain, a process the diminishes KCC2 activity. Accordingly, acute inhibition of LMTK3 increases KCC2 activity dependent upon S940 and increases neuronal Cl- extrusion. Consistent with this, LMTK3 inhibition reduced intrinsic neuronal excitability and the severity of seizure-like events in vitro. Thus, LMTK3 may have profound effects on neuronal excitability as an endogenous modulator of KCC2 activity.
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Affiliation(s)
- Noell Cho
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Georgina Kontou
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Joshua L. Smalley
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Christopher Bope
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Jacob Dengler
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Kristopher Montrose
- Cell Signal Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa 904-0495, Japan
| | - Tarek Z. Deeb
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | | | - Tadashi Yamamoto
- Cell Signal Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa 904-0495, Japan
| | - Paul A. Davies
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Georgios Giamas
- Department for Biochemistry and Biomedicine, University of Sussex Brighton, Brighton BN1 9RH, UK
| | - Stephen J. Moss
- Department of Neuroscience, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1 6BT, UK
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Cai J, Wu Z, Wang G, Zhao X, Wang X, Wang BH, Yu J, Liu X, Wang Y. The suppressive effect of the specific KCC2 modulator CLP290 on seizure in mice. Epilepsy Res 2024; 203:107365. [PMID: 38677001 DOI: 10.1016/j.eplepsyres.2024.107365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 04/03/2024] [Accepted: 04/15/2024] [Indexed: 04/29/2024]
Abstract
Epilepsy is a chronic neurological disorder characterized by episodic dysfunction of central nervous system. The most basic mechanism of epilepsy falls to the imbalance between excitation and inhibition. In adults, GABAA receptor (GABAAR) is the main inhibitory receptor to prevent neurons from developing hyperexcitability, while its inhibition relies on the low intracellular chloride anion concentration ([Cl-]i). Neuronal-specific electroneutral K+-Cl- cotransporter (KCC2) can mediate chloride efflux to lower [Cl-]i for GABAAR mediated inhibition. Our previous study has revealed that the coordinated downregulation of KCC2 and GABAAR participates in epilepsy. According to a high-throughout screen for compounds that reduce [Cl-]i, CLP290 turns out to be a specific KCC2 functional modulator. In current study, we first confirmed that CLP290 could dose-dependently suppress convulsant-induced seizures in mice in vivo as well as the epileptiform burst activities in cultured hippocampal neurons in vitro. Then, we discovered that CLP290 functioned through preventing the downregulation of the KCC2 phosphorylation at Ser940 and hence the KCC2 membrane expression during convulsant stimulation, and consequently restored the GABA inhibition. In addition, while CLP290 was given in early epileptogenesis period, it also effectively decreased the spontaneous recurrent seizures. Generally, our current results demonstrated that CLP290, as a specific KCC2 modulator by enhancing KCC2 function, not only inhibits the occurrence of the ictal seizures, but also suppresses the epileptogenic process. Therefore, we believe KCC2 may be a suitable target for future anti-epileptic drug development.
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Affiliation(s)
- Jingyi Cai
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Zhuoyi Wu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Guoxiang Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xiran Zhao
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xiaohan Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Benjamin H Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Jiangning Yu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xu Liu
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Yun Wang
- Department of Neurology, Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
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Keramidis I, McAllister BB, Bourbonnais J, Wang F, Isabel D, Rezaei E, Sansonetti R, Degagne P, Hamel JP, Nazari M, Inayat S, Dudley JC, Barbeau A, Froux L, Paquet ME, Godin AG, Mohajerani MH, De Koninck Y. Restoring neuronal chloride extrusion reverses cognitive decline linked to Alzheimer's disease mutations. Brain 2023; 146:4903-4915. [PMID: 37551444 PMCID: PMC10690023 DOI: 10.1093/brain/awad250] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/23/2023] [Accepted: 07/09/2023] [Indexed: 08/09/2023] Open
Abstract
Disinhibition during early stages of Alzheimer's disease is postulated to cause network dysfunction and hyperexcitability leading to cognitive deficits. However, the underlying molecular mechanism remains unknown. Here we show that, in mouse lines carrying Alzheimer's disease-related mutations, a loss of neuronal membrane potassium-chloride cotransporter KCC2, responsible for maintaining the robustness of GABAA-mediated inhibition, occurs pre-symptomatically in the hippocampus and prefrontal cortex. KCC2 downregulation was inversely correlated with the age-dependent increase in amyloid-β 42 (Aβ42). Acute administration of Aβ42 caused a downregulation of membrane KCC2. Loss of KCC2 resulted in impaired chloride homeostasis. Preventing the decrease in KCC2 using long term treatment with CLP290 protected against deterioration of learning and cortical hyperactivity. In addition, restoring KCC2, using short term CLP290 treatment, following the transporter reduction effectively reversed spatial memory deficits and social dysfunction, linking chloride dysregulation with Alzheimer's disease-related cognitive decline. These results reveal KCC2 hypofunction as a viable target for treatment of Alzheimer's disease-related cognitive decline; they confirm target engagement, where the therapeutic intervention takes place, and its effectiveness.
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Affiliation(s)
- Iason Keramidis
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Graduate Program in Neuroscience, Faculty of Medicine, Université Laval, Québec, QC G1V 0A6, Canada
| | - Brendan B McAllister
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Julien Bourbonnais
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Feng Wang
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Faculty of Dentistry, Université Laval, Québec, QC G1V 0A6, Canada
| | - Dominique Isabel
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Edris Rezaei
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Romain Sansonetti
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Phil Degagne
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Justin P Hamel
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Mojtaba Nazari
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Samsoon Inayat
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Jordan C Dudley
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Annie Barbeau
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Lionel Froux
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Marie-Eve Paquet
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Department of Biochemistry, Microbiology, and Bio-informatics, Université Laval, Québec, QC G1V 0A6, Canada
| | - Antoine G Godin
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Graduate Program in Neuroscience, Faculty of Medicine, Université Laval, Québec, QC G1V 0A6, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada
| | - Majid H Mohajerani
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Yves De Koninck
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Graduate Program in Neuroscience, Faculty of Medicine, Université Laval, Québec, QC G1V 0A6, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada
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van van Hugte EJH, Schubert D, Nadif Kasri N. Excitatory/inhibitory balance in epilepsies and neurodevelopmental disorders: Depolarizing γ-aminobutyric acid as a common mechanism. Epilepsia 2023; 64:1975-1990. [PMID: 37195166 DOI: 10.1111/epi.17651] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 05/13/2023] [Accepted: 05/15/2023] [Indexed: 05/18/2023]
Abstract
Epilepsy is one of the most common neurological disorders. Although many factors contribute to epileptogenesis, seizure generation is mostly linked to hyperexcitability due to alterations in excitatory/inhibitory (E/I) balance. The common hypothesis is that reduced inhibition, increased excitation, or both contribute to the etiology of epilepsy. Increasing evidence shows that this view is oversimplistic, and that increased inhibition through depolarizing γ-aminobutyric acid (GABA) similarly contributes to epileptogenisis. In early development, GABA signaling is depolarizing, inducing outward Cl- currents due to high intracellular Cl- concentrations. During maturation, the mechanisms of GABA action shift from depolarizing to hyperpolarizing, a critical event during brain development. Altered timing of this shift is associated with both neurodevelopmental disorders and epilepsy. Here, we consider the different ways that depolarizing GABA contributes to altered E/I balance and epileptogenesis, and discuss that alterations in depolarizing GABA could be a common denominator underlying seizure generation in neurodevelopmental disorders and epilepsies.
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Affiliation(s)
- Eline J H van van Hugte
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, the Netherlands
- Department of Epileptology, Academic Centre for Epileptology (ACE) Kempenhaeghe, Heeze, the Netherlands
| | - Dirk Schubert
- Department of Cognitive Neuroscience, Radboud University Medical Center, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, the Netherlands
| | - Nael Nadif Kasri
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, the Netherlands
- Department of Epileptology, Academic Centre for Epileptology (ACE) Kempenhaeghe, Heeze, the Netherlands
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Watanabe K, Ishibashi M, Suzuki T, Otsuka A, Yoshimura N, Miyake H, Fukuda A. Therapeutic effects of KCC2 chloride transporter activation on detrusor overactivity in mice with spinal cord injury. Am J Physiol Renal Physiol 2023; 324:F353-F361. [PMID: 36656987 DOI: 10.1152/ajprenal.00271.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
This study aimed to clarify whether downregulation of K+-Cl- cotransporter 2 (KCC2) in the sacral parasympathetic nucleus (SPN) of the lumbosacral spinal cord, from which the efferent pathway innervating the bladder originates, causes cellular hyperexcitability and triggers detrusor overactivity (DO) in spinal cord injury (SCI). SCI was produced by Th8-9 spinal cord transection in female C57BL/6 mice. At 4 wk after SCI, CLP290, a KCC2 activator, was administered, and cystometry was performed. Thereafter, neuronal activity with c-fos staining and KCC2 expression in cholinergic preganglionic parasympathetic neurons in the SPN was examined using immunohistochemistry. Firing properties of neurons in the SPN region were evaluated by extracellular recordings in the spinal cord slice preparations. DO evident as nonvoiding contractions was significantly reduced by CLP290 treatment in SCI mice. The number of c-fos-positive cells and coexpression of c-fos in choline acetyltransferase-positive cells were decreased in the SPN region of the SCI CLP290-treated group versus the SCI vehicle-treated group. KCC2 immunoreactivity was present on the cell membrane of SPN neurons and normalized fluorescence intensity of KCC2 in choline acetyltransferase-positive SPN neurons was decreased in the SCI vehicle-treated group versus the spinal intact vehicle-treated group but recovered in the SCI CLP290-treated group. Extracellular recordings showed that CLP290 suppressed the high-frequency firing activity of SPN neurons in SCI mice. These results indicated that SCI-induced DO is associated with downregulation of KCC2 in preganglionic parasympathetic neurons and that activation of KCC2 transporters can reduce DO, increase KCC2 expression in preganglionic parasympathetic neurons, and decrease neuronal firing of SPN neurons in SCI mice.NEW & NOTEWORTHY This study is the first report to suggest that activation of the Cl- transporter K+-Cl- cotransporter 2 may be a therapeutic modality for the treatment of spinal cord injury-induced detrusor overactivity by targeting bladder efferent pathways.
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Affiliation(s)
- Kyohei Watanabe
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
- Department of Urology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Masaru Ishibashi
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Takahisa Suzuki
- Department of Urology, Kanagawa Rehabilitation Hospital, Atsugi, Japan
- Department of Urology, Yokohama City University, Yokohama, Japan
| | - Atsushi Otsuka
- Department of Urology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Hideaki Miyake
- Department of Urology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
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9
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Cation-Chloride Cotransporters KCC2 and NKCC1 as Therapeutic Targets in Neurological and Neuropsychiatric Disorders. Molecules 2023; 28:molecules28031344. [PMID: 36771011 PMCID: PMC9920462 DOI: 10.3390/molecules28031344] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/21/2023] [Accepted: 01/25/2023] [Indexed: 02/04/2023] Open
Abstract
Neurological diseases including Alzheimer's, Huntington's disease, Parkinson's disease, Down syndrome and epilepsy, and neuropsychiatric disorders such as schizophrenia, are conditions that affect not only individuals but societies on a global scale. Current therapies offer a means for small symptomatic relief, but recently there has been increasing demand for therapeutic alternatives. The γ-aminobutyric acid (GABA)ergic signaling system has been investigated for developing new therapies as it has been noted that any dysfunction or changes to this system can contribute to disease progression. Expression of the K-Cl-2 (KCC2) and N-K-C1-1 (NKCC1) cation-chloride cotransporters (CCCs) has recently been linked to the disruption of GABAergic activity by affecting the polarity of GABAA receptor signaling. KCC2 and NKCC1 play a part in multiple neurological and neuropsychiatric disorders, making them a target of interest for potential therapies. This review explores current research suggesting the pathophysiological role and therapeutic importance of KCC2 and NKCC1 in neuropsychiatric and neurological disorders.
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Sinha AS, Wang T, Watanabe M, Hosoi Y, Sohara E, Akita T, Uchida S, Fukuda A. WNK3 kinase maintains neuronal excitability by reducing inwardly rectifying K+ conductance in layer V pyramidal neurons of mouse medial prefrontal cortex. Front Mol Neurosci 2022; 15:856262. [PMID: 36311015 PMCID: PMC9613442 DOI: 10.3389/fnmol.2022.856262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 09/22/2022] [Indexed: 11/13/2022] Open
Abstract
The with-no-lysine (WNK) family of serine-threonine kinases and its downstream kinases of STE20/SPS1-related proline/alanine-rich kinase (SPAK) and oxidative stress-responsive kinase-1 (OSR1) may regulate intracellular Cl− homeostasis through phosphorylation of cation-Cl− co-transporters. WNK3 is expressed in fetal and postnatal brains, and its expression level increases during development. Its roles in neurons, however, remain uncertain. Using WNK3 knockout (KO) mice, we investigated the role of WNK3 in the regulation of the intracellular Cl− concentration ([Cl−]i) and the excitability of layer V pyramidal neurons in the medial prefrontal cortex (mPFC). Gramicidin-perforated patch-clamp recordings in neurons from acute slice preparation at the postnatal day 21 indicated a significantly depolarized reversal potential for GABAA receptor-mediated currents by 6 mV, corresponding to the higher [Cl−]i level by ~4 mM in KO mice than in wild-type littermates. However, phosphorylation levels of SPAK and OSR1 and those of neuronal Na+-K+-2Cl− co-transporter NKCC1 and K+-Cl− co-transporter KCC2 did not significantly differ between KO and wild-type mice. Meanwhile, the resting membrane potential of neurons was more hyperpolarized by 7 mV, and the minimum stimulus current necessary for firing induction was increased in KO mice. These were due to an increased inwardly rectifying K+ (IRK) conductance, mediated by classical inwardly rectifying (Kir) channels, in KO neurons. The introduction of an active form of WNK3 into the recording neurons reversed these changes. The potential role of KCC2 function in the observed changes of KO neurons was investigated by applying a selective KCC2 activator, CLP290. This reversed the enhanced IRK conductance in KO neurons, indicating that both WNK3 and KCC2 are intimately linked in the regulation of resting K+ conductance. Evaluation of synaptic properties revealed that the frequency of miniature excitatory postsynaptic currents (mEPSCs) was reduced, whereas that of inhibitory currents (mIPSCs) was slightly increased in KO neurons. Together, the impact of these developmental changes on the membrane and synaptic properties was manifested as behavioral deficits in pre-pulse inhibition, a measure of sensorimotor gating involving multiple brain regions including the mPFC, in KO mice. Thus, the basal function of WNK3 would be the maintenance and/or development of both intrinsic and synaptic excitabilities.
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Affiliation(s)
- Adya Saran Sinha
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Tianying Wang
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Miho Watanabe
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Yasushi Hosoi
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Eisei Sohara
- Department of Nephrology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tenpei Akita
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Shinichi Uchida
- Department of Nephrology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
- *Correspondence: Atsuo Fukuda
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11
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Hudson KE, Grau JW. Ionic Plasticity: Common Mechanistic Underpinnings of Pathology in Spinal Cord Injury and the Brain. Cells 2022; 11:cells11182910. [PMID: 36139484 PMCID: PMC9496934 DOI: 10.3390/cells11182910] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 09/12/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
The neurotransmitter GABA is normally characterized as having an inhibitory effect on neural activity in the adult central nervous system (CNS), which quells over-excitation and limits neural plasticity. Spinal cord injury (SCI) can bring about a modification that weakens the inhibitory effect of GABA in the central gray caudal to injury. This change is linked to the downregulation of the potassium/chloride cotransporter (KCC2) and the consequent rise in intracellular Cl- in the postsynaptic neuron. As the intracellular concentration increases, the inward flow of Cl- through an ionotropic GABA-A receptor is reduced, which decreases its hyperpolarizing (inhibitory) effect, a modulatory effect known as ionic plasticity. The loss of GABA-dependent inhibition enables a state of over-excitation within the spinal cord that fosters aberrant motor activity (spasticity) and chronic pain. A downregulation of KCC2 also contributes to the development of a number of brain-dependent pathologies linked to states of neural over-excitation, including epilepsy, addiction, and developmental disorders, along with other diseases such as hypertension, asthma, and irritable bowel syndrome. Pharmacological treatments that target ionic plasticity have been shown to bring therapeutic benefits.
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Affiliation(s)
- Kelsey E. Hudson
- Neuroscience, Texas A&M University, College Station, TX 77843, USA
- Correspondence:
| | - James W. Grau
- Psychological & Brain Sciences, Texas A&M University, College Station, TX 77843, USA
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12
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Medel-Matus JS, Orozco-Suárez S, Escalante RG. Factors not considered in the study of drug-resistant epilepsy: Psychiatric comorbidities, age, and gender. Epilepsia Open 2022. [PMID: 34967149 DOI: 10.1002/epi4.12576.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
Abstract
In basic research and clinical practice, the control of seizures has been the most important goal, but it should not be the only one. There are factors that remain poorly understood in the study of refractory epilepsy such as the age and gender of patients and the presence of psychiatric comorbidities. It is known that in patients with drug-resistant epilepsy (DRE), the comorbidities contribute to the deterioration of the quality of life, increase the severity, and worsen the prognosis of epilepsy. Some studies have demonstrated that patients diagnosed with a co-occurrence of epilepsy and psychiatric disorders are more likely to present refractory seizures and the probability of seizure remission after pharmacotherapy is reduced. The evidence of this association suggests the presence of shared pathogenic mechanisms that may include endocrine disorders, neuroinflammatory processes, disturbances of neurotransmitters, and mechanisms triggered by stress. Additionally, significant demographic, clinical, and electrographic differences have been observed between women and men with epilepsy. Epilepsy affects the female gender in a greater proportion, although there are no studies that report whether refractoriness affects more females. The reasons behind these sex differences are unclear; however, it is likely that sex hormones and sex brain differences related to chromosomal genes play an important role. On the other hand, it has been shown in industrialized countries that prevalence of DRE is higher in the elderly when compared to youngsters. Conversely, this phenomenon is not observed in developing regions, where more cases are found in children and young adults. The correct identification and management of these factors is crucial in order to improve the quality of life of the patients.
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Affiliation(s)
- Jesús Servando Medel-Matus
- Department of Pediatrics, Neurology Division, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
| | - Sandra Orozco-Suárez
- Unit of Medical Research in Neurological Diseases, Specialty Hospital "Dr. Bernardo Sepúlveda", National Medical Center S.XXI, Mexico City, Mexico
| | - Ruby G Escalante
- Department of Pediatrics, Neurology Division, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
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13
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Molecular Mechanisms of Epilepsy: The Role of the Chloride Transporter KCC2. J Mol Neurosci 2022; 72:1500-1515. [PMID: 35819636 DOI: 10.1007/s12031-022-02041-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 06/07/2022] [Indexed: 10/17/2022]
Abstract
Epilepsy is a neurological disease characterized by abnormal or synchronous brain activity causing seizures, which may produce convulsions, minor physical signs, or a combination of symptoms. These disorders affect approximately 65 million people worldwide, from all ages and genders. Seizures apart, epileptic patients present a high risk to develop neuropsychological comorbidities such as cognitive deficits, emotional disturbance, and psychiatric disorders, which severely impair quality of life. Currently, the treatment for epilepsy includes the administration of drugs or surgery, but about 30% of the patients treated with antiepileptic drugs develop time-dependent pharmacoresistence. Therefore, further investigation about epilepsy and its causes is needed to find new pharmacological targets and innovative therapeutic strategies. Pharmacoresistance is associated to changes in neuronal plasticity and alterations of GABAA receptor-mediated neurotransmission. The downregulation of GABA inhibitory activity may arise from a positive shift in GABAA receptor reversal potential, due to an alteration in chloride homeostasis. In this paper, we review the contribution of K+-Cl--cotransporter (KCC2) to the alterations in the Cl- gradient observed in epileptic condition, and how these alterations are coupled to the increase in the excitability.
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14
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Bie B, Wu J, Lin F, Naguib M, Xu J. Suppression of hippocampal GABAergic transmission impairs memory in rodent models of Alzheimer's disease. Eur J Pharmacol 2022; 917:174771. [PMID: 35041847 DOI: 10.1016/j.ejphar.2022.174771] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/12/2022] [Accepted: 01/13/2022] [Indexed: 11/27/2022]
Abstract
Emerging evidence demonstrates the potential involvement of hippocampal GABAergic transmission in the process of memory acquisition and consolidation, while no consistent report is available to address the adaptation of hippocampal GABAergic transmission and its contribution to memory deficiency in the setting of Alzheimer's disease (AD). Brain-derived neurotrophic factor (BDNF) is a key molecule that regulates GABAergic transmission. In the brain, mature BDNF is generated from the proteolytic cleavage of proBDNF, while BDNF and proBDNF have differential effects on central GABAergic transmission. First, the present study reports a remarkable increase of proBDNF/BNDF ratio in the hippocampal CA1 area in rodent models of AD, indicating a potential impaired process of BDNF maturation from proBDNF cleavage. We report a suppressed hippocampal GABAergic strength, potentially resulting from the reduced expression of anion chloride co-transporter KCC2 and subsequent positive shift of GABAergic Cl-equilibrium potential (ECl-), which is attenuated by microinjection of BDNF with proBDNF inhibitor TAT-Pep5. We also show that normalization of proBDNF/BDNF signaling or GABAergic ECl-by intracerebroventricular (i.c.v.) administration of bumetanide remarkably improves the cognitive performance in Morris water maze test and fear conditioning test in rodent models of AD. These results demonstrate a critical role of hippocampal proBDNF/BDNF in regulating GABAergic transmission and contributing to memory dysfunction in rodent models of AD.
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Affiliation(s)
- Bihua Bie
- Department of Pain Management, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Jiang Wu
- Department of Pain Management, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Feng Lin
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Mohamed Naguib
- Department of General Anesthesiology, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Jijun Xu
- Department of Pain Management, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, 44195, USA; Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA.
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15
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Medel-Matus JS, Orozco-Suárez S, Escalante RG. Factors not considered in the study of drug-resistant epilepsy: Psychiatric comorbidities, age and gender. Epilepsia Open 2021; 7 Suppl 1:S81-S93. [PMID: 34967149 PMCID: PMC9340311 DOI: 10.1002/epi4.12576] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 12/20/2021] [Accepted: 12/27/2021] [Indexed: 11/10/2022] Open
Abstract
In basic research and clinical practice, the control of seizures has been the most important goal but it should not be the only one. There are factors that remain poorly understood in the study of refractory epilepsy such as the age and gender of patients and the presence of psychiatric comorbidities. It is known that in patients with drug-resistant epilepsy (DRE), the comorbidities contribute to the deterioration of the quality of life, increase the severity, and worsen the prognosis of epilepsy. Some studies have demonstrated that patients diagnosed with a co-occurrence of epilepsy and psychiatric disorders are more likely to present refractory seizures and the probability of seizure remission after pharmacotherapy is reduced. The evidence of this association suggests the presence of shared pathogenic mechanisms that may include endocrine disorders, neuroinflammatory processes, disturbances of neurotransmitters and mechanisms triggered by stress. Additionally, significant demographic, clinical and electrographic differences have been observed between women and men with epilepsy. Epilepsy affects the female gender in a greater proportion, although there are no studies that report whether refractoriness affects more females. The reasons behind these sex differences are unclear; however, it is likely that sex hormones and sex brain differences related to chromosomal genes play an important role. On the other hand, it has been shown in industrialized countries that prevalence of DRE is higher in the elderly when compared to youngsters. Conversely, this phenomenon is not observed in developing regions, where more cases are found in children and young adults. The correct identification and management of these factors is crucial in order to improve the quality of life of the patients.
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Affiliation(s)
- Jesús Servando Medel-Matus
- Department of Pediatrics, Neurology Division, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, U.S.A
| | - Sandra Orozco-Suárez
- Unit of Medical Research in Neurological Diseases, Specialty Hospital "Dr, Bernardo Sepúlveda", National Medical Center S.XXI, Mexico City, Mexico
| | - Ruby G Escalante
- Department of Pediatrics, Neurology Division, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, U.S.A
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