1
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Dagostino R, Gottlieb A. Tissue-specific atlas of trans-models for gene regulation elucidates complex regulation patterns. BMC Genomics 2024; 25:377. [PMID: 38632500 PMCID: PMC11022497 DOI: 10.1186/s12864-024-10317-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 04/16/2024] [Indexed: 04/19/2024] Open
Abstract
BACKGROUND Deciphering gene regulation is essential for understanding the underlying mechanisms of healthy and disease states. While the regulatory networks formed by transcription factors (TFs) and their target genes has been mostly studied with relation to cis effects such as in TF binding sites, we focused on trans effects of TFs on the expression of their transcribed genes and their potential mechanisms. RESULTS We provide a comprehensive tissue-specific atlas, spanning 49 tissues of TF variations affecting gene expression through computational models considering two potential mechanisms, including combinatorial regulation by the expression of the TFs, and by genetic variants within the TF. We demonstrate that similarity between tissues based on our discovered genes corresponds to other types of tissue similarity. The genes affected by complex TF regulation, and their modelled TFs, were highly enriched for pharmacogenomic functions, while the TFs themselves were also enriched in several cancer and metabolic pathways. Additionally, genes that appear in multiple clusters are enriched for regulation of immune system while tissue clusters include cluster-specific genes that are enriched for biological functions and diseases previously associated with the tissues forming the cluster. Finally, our atlas exposes multilevel regulation across multiple tissues, where TFs regulate other TFs through the two tested mechanisms. CONCLUSIONS Our tissue-specific atlas provides hierarchical tissue-specific trans genetic regulations that can be further studied for association with human phenotypes.
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Affiliation(s)
- Robert Dagostino
- McWilliams School of Biomedical Informatics, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Assaf Gottlieb
- McWilliams School of Biomedical Informatics, University of Texas Health Science Center at Houston, Houston, TX, USA.
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2
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Okhuarobo A, Kreifeldt M, Gandhi PJ, Lopez C, Martinez B, Fleck K, Bajo M, Bhattacharyya P, Dopico AM, Roberto M, Roberts AJ, Homanics GE, Contet C. Ethanol's interaction with BK channel α subunit residue K361 does not mediate behavioral responses to alcohol in mice. Mol Psychiatry 2024; 29:529-542. [PMID: 38135755 PMCID: PMC11116116 DOI: 10.1038/s41380-023-02346-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 11/27/2023] [Indexed: 12/24/2023]
Abstract
Large conductance potassium (BK) channels are among the most sensitive molecular targets of ethanol and genetic variations in the channel-forming α subunit have been nominally associated with alcohol use disorders. However, whether the action of ethanol at BK α influences the motivation to drink alcohol remains to be determined. To address this question, we first tested the effect of systemically administered BK channel modulators on voluntary alcohol consumption in C57BL/6J males. Penitrem A (blocker) exerted dose-dependent effects on moderate alcohol intake, while paxilline (blocker) and BMS-204352 (opener) were ineffective. Because pharmacological manipulations are inherently limited by non-specific effects, we then sought to investigate the behavioral relevance of ethanol's direct interaction with BK α by introducing in the mouse genome a point mutation known to render BK channels insensitive to ethanol while preserving their physiological function. The BK α K361N substitution prevented ethanol from reducing spike threshold in medial habenula neurons. However, it did not alter acute responses to ethanol in vivo, including ataxia, sedation, hypothermia, analgesia, and conditioned place preference. Furthermore, the mutation did not have reproducible effects on alcohol consumption in limited, continuous, or intermittent access home cage two-bottle choice paradigms conducted in both males and females. Notably, in contrast to previous observations made in mice missing BK channel auxiliary β subunits, the BK α K361N substitution had no significant impact on ethanol intake escalation induced by chronic intermittent alcohol vapor inhalation. It also did not affect the metabolic and locomotor consequences of chronic alcohol exposure. Altogether, these data suggest that the direct interaction of ethanol with BK α does not mediate the alcohol-related phenotypes examined here in mice.
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Affiliation(s)
- Agbonlahor Okhuarobo
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Max Kreifeldt
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Pauravi J Gandhi
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Catherine Lopez
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Briana Martinez
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Kiera Fleck
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Michal Bajo
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | | | - Alex M Dopico
- University of Tennessee Health Science Center, Department of Pharmacology, Addiction Science, and Toxicology, Memphis, TN, USA
| | - Marisa Roberto
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Amanda J Roberts
- The Scripps Research Institute, Animals Models Core Facility, La Jolla, CA, USA
| | - Gregg E Homanics
- University of Pittsburgh, Department of Anesthesiology and Perioperative Medicine, Pittsburgh, PA, USA
| | - Candice Contet
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA.
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3
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Sun S, Wang H. Clocking Epilepsies: A Chronomodulated Strategy-Based Therapy for Rhythmic Seizures. Int J Mol Sci 2023; 24:ijms24044223. [PMID: 36835631 PMCID: PMC9962262 DOI: 10.3390/ijms24044223] [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: 12/19/2022] [Revised: 02/08/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Epilepsy is a neurological disorder characterized by hypersynchronous recurrent neuronal activities and seizures, as well as loss of muscular control and sometimes awareness. Clinically, seizures have been reported to display daily variations. Conversely, circadian misalignment and circadian clock gene variants contribute to epileptic pathogenesis. Elucidation of the genetic bases of epilepsy is of great importance because the genetic variability of the patients affects the efficacies of antiepileptic drugs (AEDs). For this narrative review, we compiled 661 epilepsy-related genes from the PHGKB and OMIM databases and classified them into 3 groups: driver genes, passenger genes, and undetermined genes. We discuss the potential roles of some epilepsy driver genes based on GO and KEGG analyses, the circadian rhythmicity of human and animal epilepsies, and the mutual effects between epilepsy and sleep. We review the advantages and challenges of rodents and zebrafish as animal models for epileptic studies. Finally, we posit chronomodulated strategy-based chronotherapy for rhythmic epilepsies, integrating several lines of investigation for unraveling circadian mechanisms underpinning epileptogenesis, chronopharmacokinetic and chronopharmacodynamic examinations of AEDs, as well as mathematical/computational modeling to help develop time-of-day-specific AED dosing schedules for rhythmic epilepsy patients.
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Affiliation(s)
- Sha Sun
- Center for Circadian Clocks, Soochow University, Suzhou 215123, China
- School of Biology and Basic Medical Sciences, Suzhou Medical College, Soochow University, Suzhou 215123, China
| | - Han Wang
- Center for Circadian Clocks, Soochow University, Suzhou 215123, China
- School of Biology and Basic Medical Sciences, Suzhou Medical College, Soochow University, Suzhou 215123, China
- Correspondence: or ; Tel.: +86-186-0512-8971
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4
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Ancatén-González C, Segura I, Alvarado-Sánchez R, Chávez AE, Latorre R. Ca 2+- and Voltage-Activated K + (BK) Channels in the Nervous System: One Gene, a Myriad of Physiological Functions. Int J Mol Sci 2023; 24:3407. [PMID: 36834817 PMCID: PMC9967218 DOI: 10.3390/ijms24043407] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 02/11/2023] Open
Abstract
BK channels are large conductance potassium channels characterized by four pore-forming α subunits, often co-assembled with auxiliary β and γ subunits to regulate Ca2+ sensitivity, voltage dependence and gating properties. BK channels are abundantly expressed throughout the brain and in different compartments within a single neuron, including axons, synaptic terminals, dendritic arbors, and spines. Their activation produces a massive efflux of K+ ions that hyperpolarizes the cellular membrane. Together with their ability to detect changes in intracellular Ca2+ concentration, BK channels control neuronal excitability and synaptic communication through diverse mechanisms. Moreover, increasing evidence indicates that dysfunction of BK channel-mediated effects on neuronal excitability and synaptic function has been implicated in several neurological disorders, including epilepsy, fragile X syndrome, mental retardation, and autism, as well as in motor and cognitive behavior. Here, we discuss current evidence highlighting the physiological importance of this ubiquitous channel in regulating brain function and its role in the pathophysiology of different neurological disorders.
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Affiliation(s)
- Carlos Ancatén-González
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
- Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Ignacio Segura
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Rosangelina Alvarado-Sánchez
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
- Doctorado en Ciencias Mención Biofísica y Biología Computacional, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Andrés E. Chávez
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
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5
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Buchin A, de Frates R, Nandi A, Mann R, Chong P, Ng L, Miller J, Hodge R, Kalmbach B, Bose S, Rutishauser U, McConoughey S, Lein E, Berg J, Sorensen S, Gwinn R, Koch C, Ting J, Anastassiou CA. Multi-modal characterization and simulation of human epileptic circuitry. Cell Rep 2022; 41:111873. [PMID: 36577383 PMCID: PMC9841067 DOI: 10.1016/j.celrep.2022.111873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 06/16/2022] [Accepted: 12/02/2022] [Indexed: 12/28/2022] Open
Abstract
Temporal lobe epilepsy is the fourth most common neurological disorder, with about 40% of patients not responding to pharmacological treatment. Increased cellular loss is linked to disease severity and pathological phenotypes such as heightened seizure propensity. While the hippocampus is the target of therapeutic interventions, the impact of the disease at the cellular level remains unclear. Here, we show that hippocampal granule cells change with disease progression as measured in living, resected hippocampal tissue excised from patients with epilepsy. We show that granule cells increase excitability and shorten response latency while also enlarging in cellular volume and spine density. Single-nucleus RNA sequencing combined with simulations ascribes the changes to three conductances: BK, Cav2.2, and Kir2.1. In a network model, we show that these changes related to disease progression bring the circuit into a more excitable state, while reversing them produces a less excitable, "early-disease-like" state.
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Affiliation(s)
- Anatoly Buchin
- Allen Institute for Brain Science, Seattle, WA, USA,Present address: Cajal Neuroscience, Inc., Seattle, WA, USA,Correspondence: (A.B.), (C.A.A.)
| | - Rebecca de Frates
- Allen Institute for Brain Science, Seattle, WA, USA,These authors contributed equally
| | - Anirban Nandi
- Allen Institute for Brain Science, Seattle, WA, USA,These authors contributed equally
| | - Rusty Mann
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Peter Chong
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Lindsay Ng
- Allen Institute for Brain Science, Seattle, WA, USA
| | | | | | - Brian Kalmbach
- Allen Institute for Brain Science, Seattle, WA, USA,University of Washington, Seattle, WA, USA
| | - Soumita Bose
- Allen Institute for Brain Science, Seattle, WA, USA,CiperHealth, San Francisco, CA, USA
| | - Ueli Rutishauser
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA,Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA,Center for Neural Science and Medicine, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Stephen McConoughey
- Allen Institute for Brain Science, Seattle, WA, USA,Present address: Institute for Advanced Clinical Trials for Children, 9200 Corporate Blvd, Suite 350, Rockville, MD 20850, USA
| | - Ed Lein
- Allen Institute for Brain Science, Seattle, WA, USA,University of Washington, Seattle, WA, USA
| | - Jim Berg
- Allen Institute for Brain Science, Seattle, WA, USA
| | | | | | | | - Jonathan Ting
- Allen Institute for Brain Science, Seattle, WA, USA,University of Washington, Seattle, WA, USA
| | - Costas A. Anastassiou
- Allen Institute for Brain Science, Seattle, WA, USA,Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA,Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA,Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA,Center for Neural Science and Medicine, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA,Lead contact,Correspondence: (A.B.), (C.A.A.)
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6
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Park SM, Roache CE, Iffland PH, Moldenhauer HJ, Matychak KK, Plante AE, Lieberman AG, Crino PB, Meredith A. BK channel properties correlate with neurobehavioral severity in three KCNMA1-linked channelopathy mouse models. eLife 2022; 11:e77953. [PMID: 35819138 PMCID: PMC9275823 DOI: 10.7554/elife.77953] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 06/01/2022] [Indexed: 12/14/2022] Open
Abstract
KCNMA1 forms the pore of BK K+ channels, which regulate neuronal and muscle excitability. Recently, genetic screening identified heterozygous KCNMA1 variants in a subset of patients with debilitating paroxysmal non-kinesigenic dyskinesia, presenting with or without epilepsy (PNKD3). However, the relevance of KCNMA1 mutations and the basis for clinical heterogeneity in PNKD3 has not been established. Here, we evaluate the relative severity of three KCNMA1 patient variants in BK channels, neurons, and mice. In heterologous cells, BKN999S and BKD434G channels displayed gain-of-function (GOF) properties, whereas BKH444Q channels showed loss-of-function (LOF) properties. The relative degree of channel activity was BKN999S > BKD434G>WT > BKH444Q. BK currents and action potential firing were increased, and seizure thresholds decreased, in Kcnma1N999S/WT and Kcnma1D434G/WT transgenic mice but not Kcnma1H444Q/WT mice. In a novel behavioral test for paroxysmal dyskinesia, the more severely affected Kcnma1N999S/WT mice became immobile after stress. This was abrogated by acute dextroamphetamine treatment, consistent with PNKD3-affected individuals. Homozygous Kcnma1D434G/D434G mice showed similar immobility, but in contrast, homozygous Kcnma1H444Q/H444Q mice displayed hyperkinetic behavior. These data establish the relative pathogenic potential of patient alleles as N999S>D434G>H444Q and validate Kcnma1N999S/WT mice as a model for PNKD3 with increased seizure propensity.
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Affiliation(s)
- Su Mi Park
- Department of Physiology, University of Maryland School of MedicineBaltimoreUnited States
| | - Cooper E Roache
- Department of Physiology, University of Maryland School of MedicineBaltimoreUnited States
| | - Philip H Iffland
- Department of Neurology, University of Maryland School of MedicineBaltimoreUnited States
| | - Hans J Moldenhauer
- Department of Physiology, University of Maryland School of MedicineBaltimoreUnited States
| | - Katia K Matychak
- Department of Physiology, University of Maryland School of MedicineBaltimoreUnited States
| | - Amber E Plante
- Department of Physiology, University of Maryland School of MedicineBaltimoreUnited States
| | - Abby G Lieberman
- Department of Pharmacology, University of Maryland School of MedicineBaltimoreUnited States
| | - Peter B Crino
- Department of Neurology, University of Maryland School of MedicineBaltimoreUnited States
| | - Andrea Meredith
- Department of Physiology, University of Maryland School of MedicineBaltimoreUnited States
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7
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Kruse M, Whitten RJ. Control of Neuronal Excitability by Cell Surface Receptor Density and Phosphoinositide Metabolism. Front Pharmacol 2021; 12:663840. [PMID: 33967808 PMCID: PMC8097148 DOI: 10.3389/fphar.2021.663840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 03/29/2021] [Indexed: 12/27/2022] Open
Abstract
Phosphoinositides are members of a family of minor phospholipids that make up about 1% of all lipids in most cell types. Despite their low abundance they have been found to be essential regulators of neuronal activities such as action potential firing, release and re-uptake of neurotransmitters, and interaction of cytoskeletal proteins with the plasma membrane. Activation of several different neurotransmitter receptors can deplete phosphoinositide levels by more than 90% in seconds, thereby profoundly altering neuronal behavior; however, despite the physiological importance of this mechanism we still lack a profound quantitative understanding of the connection between phosphoinositide metabolism and neuronal activity. Here, we present a model that describes phosphoinositide metabolism and phosphoinositide-dependent action potential firing in sympathetic neurons. The model allows for a simulation of activation of muscarinic acetylcholine receptors and its effects on phosphoinositide levels and their regulation of action potential firing in these neurons. In this paper, we describe the characteristics of the model, its calibration to experimental data, and use the model to analyze how alterations of surface density of muscarinic acetylcholine receptors or altered activity levels of a key enzyme of phosphoinositide metabolism influence action potential firing of sympathetic neurons. In conclusion, the model provides a comprehensive framework describing the connection between muscarinic acetylcholine signaling, phosphoinositide metabolism, and action potential firing in sympathetic neurons which can be used to study the role of these signaling systems in health and disease.
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Affiliation(s)
- Martin Kruse
- Department of Biology, Bates College, Lewiston, ME, United States
- Program in Neuroscience, Bates College, Lewiston, ME, United States
| | - Rayne J. Whitten
- Program in Neuroscience, Bates College, Lewiston, ME, United States
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8
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Avchalumov Y, Oliver RJ, Trenet W, Heyer Osorno RE, Sibley BD, Purohit DC, Contet C, Roberto M, Woodward JJ, Mandyam CD. Chronic ethanol exposure differentially alters neuronal function in the medial prefrontal cortex and dentate gyrus. Neuropharmacology 2020; 185:108438. [PMID: 33333103 DOI: 10.1016/j.neuropharm.2020.108438] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 12/06/2020] [Accepted: 12/09/2020] [Indexed: 12/28/2022]
Abstract
Alterations in the function of prefrontal cortex (PFC) and hippocampus have been implicated in underlying the relapse to alcohol seeking behaviors in humans and animal models of moderate to severe alcohol use disorders (AUD). Here we used chronic intermittent ethanol vapor exposure (CIE), 21d protracted abstinence following CIE (21d AB), and re-exposure to one vapor session during protracted abstinence (re-exposure) to evaluate the effects of chronic ethanol exposure on basal synaptic function, neuronal excitability and expression of key synaptic proteins that play a role in neuronal excitability in the medial PFC (mPFC) and dentate gyrus (DG). CIE consistently enhanced excitability of layer 2/3 pyramidal neurons in the mPFC and granule cell neurons in the DG. In the DG, this effect persisted during 21d AB. Re-exposure did not enhance excitability, suggesting resistance to vapor-induced effects. Analysis of action potential kinetics revealed that altered afterhyperpolarization, rise time and decay time constants are associated with the altered excitability during CIE, 21d AB and re-exposure. Molecular adaptations that may underlie increases in neuronal excitability under these different conditions were identified. Quantitative polymerase chain reaction of large-conductance potassium (BK) channel subunit mRNA in PFC and DG tissue homogenates did not show altered expression patterns of BK subunits. Western blotting demonstrates enhanced phosphorylation of Ca2⁺/calmodulin-dependent protein kinase II (CaMKII), and reduced phosphorylation of glutamate receptor GluN2A/2B subunits. These results suggest a novel relationship between activity of CaMKII and GluN receptors in the mPFC and DG, and neuronal excitability in these brain regions in the context of moderate to severe AUD.
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Affiliation(s)
| | | | - Wulfran Trenet
- VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | | | | | | | - Candice Contet
- Departments of Molecular Medicine and Neuroscience, Scripps Research, La Jolla, CA, 92037, USA
| | - Marisa Roberto
- Departments of Molecular Medicine and Neuroscience, Scripps Research, La Jolla, CA, 92037, USA
| | - John J Woodward
- Departments of Neuroscience and Psychiatry and Behavioral Sciences, Charleston Alcohol Research Center, Addiction Sciences Division, Medical University of South Carolina, Charleston, SC, USA
| | - Chitra D Mandyam
- VA San Diego Healthcare System, San Diego, CA, 92161, USA; Departments of Molecular Medicine and Neuroscience, Scripps Research, La Jolla, CA, 92037, USA; Department of Anesthesiology, University of California San Diego, San Diego, CA, 92161, USA.
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9
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Verhoog QP, Holtman L, Aronica E, van Vliet EA. Astrocytes as Guardians of Neuronal Excitability: Mechanisms Underlying Epileptogenesis. Front Neurol 2020; 11:591690. [PMID: 33324329 PMCID: PMC7726323 DOI: 10.3389/fneur.2020.591690] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/26/2020] [Indexed: 12/11/2022] Open
Abstract
Astrocytes are key homeostatic regulators in the central nervous system and play important roles in physiology. After brain damage caused by e.g., status epilepticus, traumatic brain injury, or stroke, astrocytes may adopt a reactive phenotype. This process of reactive astrogliosis is important to restore brain homeostasis. However, persistent reactive astrogliosis can be detrimental for the brain and contributes to the development of epilepsy. In this review, we will focus on physiological functions of astrocytes in the normal brain as well as pathophysiological functions in the epileptogenic brain, with a focus on acquired epilepsy. We will discuss the role of astrocyte-related processes in epileptogenesis, including reactive astrogliosis, disturbances in energy supply and metabolism, gliotransmission, and extracellular ion concentrations, as well as blood-brain barrier dysfunction and dysregulation of blood flow. Since dysfunction of astrocytes can contribute to epilepsy, we will also discuss their role as potential targets for new therapeutic strategies.
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Affiliation(s)
- Quirijn P. Verhoog
- Leiden Academic Center for Drug Research, Leiden University, Leiden, Netherlands
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Linda Holtman
- Leiden Academic Center for Drug Research, Leiden University, Leiden, Netherlands
| | - Eleonora Aronica
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
| | - Erwin A. van Vliet
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
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10
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Yousuf MS, Samtleben S, Lamothe SM, Friedman TN, Catuneanu A, Thorburn K, Desai M, Tenorio G, Schenk GJ, Ballanyi K, Kurata HT, Simmen T, Kerr BJ. Endoplasmic reticulum stress in the dorsal root ganglia regulates large-conductance potassium channels and contributes to pain in a model of multiple sclerosis. FASEB J 2020; 34:12577-12598. [PMID: 32677089 DOI: 10.1096/fj.202001163r] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/25/2020] [Accepted: 07/09/2020] [Indexed: 01/22/2023]
Abstract
Neuropathic pain is a common symptom of multiple sclerosis (MS) and current treatment options are ineffective. In this study, we investigated whether endoplasmic reticulum (ER) stress in dorsal root ganglia (DRG) contributes to pain hypersensitivity in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Inflammatory cells and increased levels of ER stress markers are evident in post-mortem DRGs from MS patients. Similarly, we observed ER stress in the DRG of mice with EAE and relieving ER stress with a chemical chaperone, 4-phenylbutyric acid (4-PBA), reduced pain hypersensitivity. In vitro, 4-PBA and the selective PERK inhibitor, AMG44, normalize cytosolic Ca2+ transients in putative DRG nociceptors. We went on to assess disease-mediated changes in the functional properties of Ca2+ -sensitive BK-type K+ channels in DRG neurons. We found that the conductance-voltage (GV) relationship of BK channels was shifted to a more positive voltage, together with a more depolarized resting membrane potential in EAE cells. Our results suggest that ER stress in sensory neurons of MS patients and mice with EAE is a source of pain and that ER stress modulators can effectively counteract this phenotype.
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Affiliation(s)
- Muhammad Saad Yousuf
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Samira Samtleben
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| | - Shawn M Lamothe
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Timothy N Friedman
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Ana Catuneanu
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Kevin Thorburn
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Mansi Desai
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Gustavo Tenorio
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, AB, Canada
| | - Geert J Schenk
- Department of Anatomy and Neurosciences, Neuroscience Amsterdam, Amsterdam UMC, VU University Medical Center, VUmc MS Center Amsterdam, Amsterdam, The Netherlands
| | - Klaus Ballanyi
- Department of Physiology, University of Alberta, Edmonton, AB, Canada
| | - Harley T Kurata
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Thomas Simmen
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| | - Bradley J Kerr
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Department of Pharmacology, University of Alberta, Edmonton, AB, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, AB, Canada
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11
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Vigil FA, Bozdemir E, Bugay V, Chun SH, Hobbs M, Sanchez I, Hastings SD, Veraza RJ, Holstein DM, Sprague SM, M Carver C, Cavazos JE, Brenner R, Lechleiter JD, Shapiro MS. Prevention of brain damage after traumatic brain injury by pharmacological enhancement of KCNQ (Kv7, "M-type") K + currents in neurons. J Cereb Blood Flow Metab 2020; 40:1256-1273. [PMID: 31272312 PMCID: PMC7238379 DOI: 10.1177/0271678x19857818] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Nearly three million people in the USA suffer traumatic brain injury (TBI) yearly; however, there are no pre- or post-TBI treatment options available. KCNQ2-5 voltage-gated K+ channels underlie the neuronal "M current", which plays a dominant role in the regulation of neuronal excitability. Our strategy towards prevention of TBI-induced brain damage is predicated on the suggested hyper-excitability of neurons induced by TBIs, and the decrease in neuronal excitation upon pharmacological augmentation of M/KCNQ K+ currents. Seizures are very common after a TBI, making further seizures and development of epilepsy disease more likely. Our hypothesis is that TBI-induced hyperexcitability and ischemia/hypoxia lead to metabolic stress, cell death and a maladaptive inflammatory response that causes further downstream morbidity. Using the mouse controlled closed-cortical impact blunt TBI model, we found that systemic administration of the prototype M-channel "opener", retigabine (RTG), 30 min after TBI, reduces the post-TBI cascade of events, including spontaneous seizures, enhanced susceptibility to chemo-convulsants, metabolic stress, inflammatory responses, blood-brain barrier breakdown, and cell death. This work suggests that acutely reducing neuronal excitability and energy demand via M-current enhancement may be a novel model of therapeutic intervention against post-TBI brain damage and dysfunction.
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Affiliation(s)
- Fabio A Vigil
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Eda Bozdemir
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Vladislav Bugay
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Sang H Chun
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - MaryAnn Hobbs
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Isamar Sanchez
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Shayne D Hastings
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Rafael J Veraza
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Deborah M Holstein
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Shane M Sprague
- Department of Neurosurgery, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Chase M Carver
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Jose E Cavazos
- Department of Neurology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Robert Brenner
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - James D Lechleiter
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Mark S Shapiro
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
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12
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Zhu J, Tsai NP. Ubiquitination and E3 Ubiquitin Ligases in Rare Neurological Diseases with Comorbid Epilepsy. Neuroscience 2020; 428:90-99. [DOI: 10.1016/j.neuroscience.2019.12.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/19/2022]
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13
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Carver CM, Hastings SD, Cook ME, Shapiro MS. Functional responses of the hippocampus to hyperexcitability depend on directed, neuron-specific KCNQ2 K + channel plasticity. Hippocampus 2019; 30:435-455. [PMID: 31621989 DOI: 10.1002/hipo.23163] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/24/2019] [Accepted: 08/30/2019] [Indexed: 12/14/2022]
Abstract
M-type (KCNQ2/3) K+ channels play dominant roles in regulation of active and passive neuronal discharge properties such as resting membrane potential, spike-frequency adaptation, and hyper-excitatory states. However, plasticity of M-channel expression and function in nongenetic forms of epileptogenesis are still not well understood. Using transgenic mice with an EGFP reporter to detect expression maps of KCNQ2 mRNA, we assayed hyperexcitability-induced alterations in KCNQ2 transcription across subregions of the hippocampus. Pilocarpine and pentylenetetrazol chemoconvulsant models of seizure induction were used, and brain tissue examined 48 hr later. We observed increases in KCNQ2 mRNA in CA1 and CA3 pyramidal neurons after chemoconvulsant-induced hyperexcitability at 48 hr, but no significant change was observed in dentate gyrus (DG) granule cells. Using chromogenic in situ hybridization assays, changes to KCNQ3 transcription were not detected after hyper-excitation challenge, but the results for KCNQ2 paralleled those using the KCNQ2-mRNA reporter mice. In mice 7 days after pilocarpine challenge, levels of KCNQ2 mRNA were similar in all regions to those from control mice. In brain-slice electrophysiology recordings, CA1 pyramidal neurons demonstrated increased M-current amplitudes 48 hr after hyperexcitability; however, there were no significant changes to DG granule cell M-current amplitude. Traumatic brain injury induced significantly greater KCNQ2 expression in the hippocampal hemisphere that was ipsilateral to the trauma. In vivo, after a secondary challenge with subconvulsant dose of pentylenetetrazole, control mice were susceptible to tonic-clonic seizures, whereas mice administered the M-channel opener retigabine were protected from such seizures. This study demonstrates that increased excitatory activity promotes KCNQ2 upregulation in the hippocampus in a cell-type specific manner. Such novel ion channel expressional plasticity may serve as a compensatory mechanism after a hyperexcitable event, at least in the short term. The upregulation described could be potentially leveraged in anticonvulsant enhancement of KCNQ2 channels as therapeutic target for preventing onset of epileptogenic seizures.
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Affiliation(s)
- Chase M Carver
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, Texas
| | - Shayne D Hastings
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, Texas
| | - Mileah E Cook
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, Texas
| | - Mark S Shapiro
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, Texas
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14
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Bailey CS, Moldenhauer HJ, Park SM, Keros S, Meredith AL. KCNMA1-linked channelopathy. J Gen Physiol 2019; 151:1173-1189. [PMID: 31427379 PMCID: PMC6785733 DOI: 10.1085/jgp.201912457] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/13/2019] [Indexed: 12/20/2022] Open
Abstract
Bailey et al. review a new neurological channelopathy associated with KCNMA1, encoding the BK voltage- and Ca2+-activated K+ channel. KCNMA1 encodes the pore-forming α subunit of the “Big K+” (BK) large conductance calcium and voltage-activated K+ channel. BK channels are widely distributed across tissues, including both excitable and nonexcitable cells. Expression levels are highest in brain and muscle, where BK channels are critical regulators of neuronal excitability and muscle contractility. A global deletion in mouse (KCNMA1−/−) is viable but exhibits pathophysiology in many organ systems. Yet despite the important roles in animal models, the consequences of dysfunctional BK channels in humans are not well characterized. Here, we summarize 16 rare KCNMA1 mutations identified in 37 patients dating back to 2005, with an array of clinically defined pathological phenotypes collectively referred to as “KCNMA1-linked channelopathy.” These mutations encompass gain-of-function (GOF) and loss-of-function (LOF) alterations in BK channel activity, as well as several variants of unknown significance (VUS). Human KCNMA1 mutations are primarily associated with neurological conditions, including seizures, movement disorders, developmental delay, and intellectual disability. Due to the recent identification of additional patients, the spectrum of symptoms associated with KCNMA1 mutations has expanded but remains primarily defined by brain and muscle dysfunction. Emerging evidence suggests the functional BK channel alterations produced by different KCNMA1 alleles may associate with semi-distinct patient symptoms, such as paroxysmal nonkinesigenic dyskinesia (PNKD) with GOF and ataxia with LOF. However, due to the de novo origins for the majority of KCNMA1 mutations identified to date and the phenotypic variability exhibited by patients, additional evidence is required to establish causality in most cases. The symptomatic picture developing from patients with KCNMA1-linked channelopathy highlights the importance of better understanding the roles BK channels play in regulating cell excitability. Establishing causality between KCNMA1-linked BK channel dysfunction and specific patient symptoms may reveal new treatment approaches with the potential to increase therapeutic efficacy over current standard regimens.
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Affiliation(s)
- Cole S Bailey
- Dept. of Physiology, University of Maryland School of Medicine, Baltimore, MD
| | - Hans J Moldenhauer
- Dept. of Physiology, University of Maryland School of Medicine, Baltimore, MD
| | - Su Mi Park
- Dept. of Physiology, University of Maryland School of Medicine, Baltimore, MD
| | - Sotirios Keros
- Department of Pediatrics, University of South Dakota Sanford School of Medicine, Sioux Falls, SD
| | - Andrea L Meredith
- Dept. of Physiology, University of Maryland School of Medicine, Baltimore, MD
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15
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Tabatabaee S, Baker D, Selwood DL, Whalley BJ, Stephens GJ. The Cannabinoid-Like Compound, VSN16R, Acts on Large Conductance, Ca 2+-Activated K + Channels to Modulate Hippocampal CA1 Pyramidal Neuron Firing. Pharmaceuticals (Basel) 2019; 12:E104. [PMID: 31277369 PMCID: PMC6789497 DOI: 10.3390/ph12030104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/17/2019] [Accepted: 06/20/2019] [Indexed: 12/15/2022] Open
Abstract
Large conductance, Ca2+-activated K+ (BKCa) channels are widely expressed in the central nervous system, where they regulate action potential duration, firing frequency and consequential neurotransmitter release. Moreover, drug action on, mutations to, or changes in expression levels of BKCa can modulate neuronal hyperexcitability. Amongst other potential mechanisms of action, cannabinoid compounds have recently been reported to activate BKCa channels. Here, we examined the effects of the cannabinoid-like compound (R,Z)-3-(6-(dimethylamino)-6-oxohex-1-en-1-yl)-N-(1-hydroxypropan-2-yl) benzamide (VSN16R) at CA1 pyramidal neurons in hippocampal ex vivo brain slices using current clamp electrophysiology. We also investigated effects of the BKCa channel blockers iberiotoxin (IBTX) and the novel 7-pra-martentoxin (7-Pra-MarTx) on VSN16R action. VSN16R (100 μM) increased first and second fast after-hyperpolarization (fAHP) amplitude, decreased first and second inter spike interval (ISI) and shortened first action potential (AP) width under high frequency stimulation protocols in mouse hippocampal pyramidal neurons. IBTX (100 nM) decreased first fAHP amplitude, increased second ISI and broadened first and second AP width under high frequency stimulation protocols; IBTX also broadened first and second AP width under low frequency stimulation protocols. IBTX blocked effects of VSN16R on fAHP amplitude and ISI. 7-Pra-MarTx (100 nM) had no significant effects on fAHP amplitude and ISI but, unlike IBTX, shortened first and second AP width under high frequency stimulation protocols; 7-Pra-MarTx also shortened second AP width under low frequency stimulation protocols. However, in the presence of 7-Pra-MarTx, VSN16R retained some effects on AP waveform under high frequency stimulation protocols; moreover, VSN16R effects were revealed under low frequency stimulation protocols. These findings demonstrate that VSN16R has effects in native hippocampal neurons consistent with its causing an increase in initial firing frequency via activation of IBTX-sensitive BKCa channels. The differential pharmacological effects described suggest that VSN16R may differentially target BKCa channel subtypes.
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Affiliation(s)
| | - David Baker
- Centre for Neuroscience and Trauma, Blizard Institute, Queen Mary University of London, London E1 4AT, UK
| | - David L Selwood
- Department of Medicinal Chemistry, UCL Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | | | - Gary J Stephens
- Reading School of Pharmacy, University of Reading, Reading RG6 6AP, UK.
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16
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Liu NN, Xie H, Xiang-Wei WS, Gao K, Wang TS, Jiang YW. The absence of NIPA2 enhances neural excitability through BK (big potassium) channels. CNS Neurosci Ther 2019; 25:865-875. [PMID: 30895737 PMCID: PMC6630003 DOI: 10.1111/cns.13119] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/18/2019] [Accepted: 02/19/2019] [Indexed: 11/30/2022] Open
Abstract
AIM To reveal the pathogenesis and find the precision treatment for the childhood absence epilepsy (CAE) patients with NIPA2 mutations. METHODS We performed whole-cell patch-clamp recordings to measure the electrophysiological properties of layer V neocortical somatosensory pyramidal neurons in wild-type (WT) and NIPA2-knockout mice. RESULTS We identified that layer V neocortical somatosensory pyramidal neurons isolated from the NIPA2-knockout mice displayed higher frequency of spontaneous and evoked action potential, broader half-width of evoked action potential, and smaller currents of BK channels than those from the WT mice. NS11021, a specific BK channel opener, reduced neuronal excitability in the NIPA2-knockout mice. Paxilline, a selective BK channel blocker, treated WT neurons and could simulate the situation of NIPA2-knockout group, thereby suggesting that the absence of NIPA2 enhanced the excitability of neocortical somatosensory pyramidal neurons by decreasing the currents of BK channels. Zonisamide, an anti-epilepsy drug, reduced action potential firing in NIPA2-knockout mice through increasing BK channel currents. CONCLUSION The results indicate that the absence of NIPA2 enhances neural excitability through BK channels. Zonisamide is probably a potential treatment for NIPA2 mutation-induced epilepsy, which may provide a basis for the development of new treatment strategies for epilepsy.
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Affiliation(s)
- Na-Na Liu
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China
| | - Han Xie
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China
| | - Wen-Shu Xiang-Wei
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China
| | - Kai Gao
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China
| | - Tian-Shuang Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China
| | - Yu-Wu Jiang
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Beijing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases, Beijing, China
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17
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Kshatri AS, Gonzalez-Hernandez A, Giraldez T. Physiological Roles and Therapeutic Potential of Ca 2+ Activated Potassium Channels in the Nervous System. Front Mol Neurosci 2018; 11:258. [PMID: 30104956 PMCID: PMC6077210 DOI: 10.3389/fnmol.2018.00258] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 07/06/2018] [Indexed: 12/21/2022] Open
Abstract
Within the potassium ion channel family, calcium activated potassium (KCa) channels are unique in their ability to couple intracellular Ca2+ signals to membrane potential variations. KCa channels are diversely distributed throughout the central nervous system and play fundamental roles ranging from regulating neuronal excitability to controlling neurotransmitter release. The physiological versatility of KCa channels is enhanced by alternative splicing and co-assembly with auxiliary subunits, leading to fundamental differences in distribution, subunit composition and pharmacological profiles. Thus, understanding specific KCa channels’ mechanisms in neuronal function is challenging. Based on their single channel conductance, KCa channels are divided into three subtypes: small (SK, 4–14 pS), intermediate (IK, 32–39 pS) and big potassium (BK, 200–300 pS) channels. This review describes the biophysical characteristics of these KCa channels, as well as their physiological roles and pathological implications. In addition, we also discuss the current pharmacological strategies and challenges to target KCa channels for the treatment of various neurological and psychiatric disorders.
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Affiliation(s)
- Aravind S Kshatri
- Department of Basic Medical Sciences, Medical School, Universidad de La Laguna, Tenerife, Spain.,Instituto de Tecnologias Biomedicas, Universidad de La Laguna, Tenerife, Spain
| | - Alberto Gonzalez-Hernandez
- Department of Basic Medical Sciences, Medical School, Universidad de La Laguna, Tenerife, Spain.,Instituto de Tecnologias Biomedicas, Universidad de La Laguna, Tenerife, Spain
| | - Teresa Giraldez
- Department of Basic Medical Sciences, Medical School, Universidad de La Laguna, Tenerife, Spain.,Instituto de Tecnologias Biomedicas, Universidad de La Laguna, Tenerife, Spain
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18
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Kelly SP, Risley MG, Miranda LE, Dawson-Scully K. Contribution of a natural polymorphism in protein kinase G modulates electroconvulsive seizure recovery in Drosophila melanogaster. ACTA ACUST UNITED AC 2018; 221:jeb.179747. [PMID: 29798846 DOI: 10.1242/jeb.179747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/21/2018] [Indexed: 11/20/2022]
Abstract
Drosophila melanogaster is a well-characterized model for neurological disorders and is widely used for investigating causes of altered neuronal excitability leading to seizure-like behavior. One method used to analyze behavioral output of neuronal perturbance is recording the time to locomotor recovery from an electroconvulsive shock. Based on this behavior, we sought to quantify seizure susceptibility in larval D. melanogaster with differences in the enzymatic activity levels of a major protein, cGMP-dependent protein kinase (PKG). PKG, encoded by foraging, has two natural allelic variants and has previously been implicated in several important physiological characteristics including: foraging patterns, learning and memory, and environmental stress tolerance. The well-established NO/cGMP/PKG signaling pathway found in the fly, which potentially targets downstream K+ channel(s), ultimately impacts membrane excitability, leading to our hypothesis: altering PKG enzymatic activity modulates time to recovery from an electroconvulsive seizure. Our results show that by both genetically and pharmacologically increasing PKG enzymatic activity, we can decrease the locomotor recovery time from an electroconvulsive seizure in larval D. melanogaster.
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Affiliation(s)
- Stephanie P Kelly
- Florida Atlantic University, Department of Biological Sciences, Boca Raton, FL 33431, USA
| | - Monica G Risley
- Florida Atlantic University, Department of Biological Sciences, Boca Raton, FL 33431, USA.,International Max-Planck Research School (IMPRS) for Brain and Behavior, Boca Raton, FL 33431, USA
| | - Leonor E Miranda
- Florida Atlantic University, Department of Biological Sciences, Boca Raton, FL 33431, USA
| | - Ken Dawson-Scully
- Florida Atlantic University, Department of Biological Sciences, Boca Raton, FL 33431, USA
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