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Locskai LF, Alyenbaawi H, Allison WT. Antiepileptic Drugs as Potential Dementia Prophylactics Following Traumatic Brain Injury. Annu Rev Pharmacol Toxicol 2024; 64:577-598. [PMID: 37788493 DOI: 10.1146/annurev-pharmtox-051921-013930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Seizures and other forms of neurovolatility are emerging as druggable prodromal mechanisms that link traumatic brain injury (TBI) to the progression of later dementias. TBI neurotrauma has both acute and long-term impacts on health, and TBI is a leading risk factor for dementias, including chronic traumatic encephalopathy and Alzheimer's disease. Treatment of TBI already considers acute management of posttraumatic seizures and epilepsy, and impressive efforts have optimized regimens of antiepileptic drugs (AEDs) toward that goal. Here we consider that expanding these management strategies could determine which AED regimens best prevent dementia progression in TBI patients. Challenges with this prophylactic strategy include the potential consequences of prolonged AED treatment and that a large subset of patients are refractory to available AEDs. Addressing these challenges is warranted because the management of seizure activity following TBI offers a rare opportunity to prevent the onset or progression of devastating dementias.
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Affiliation(s)
- Laszlo F Locskai
- Centre for Prions and Protein Folding Diseases and Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada;
| | - Hadeel Alyenbaawi
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al Majmaah, Saudi Arabia
| | - W Ted Allison
- Centre for Prions and Protein Folding Diseases and Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada;
- Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
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2
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Dalla Porta L, Barbero-Castillo A, Sanchez-Sanchez JM, Sanchez-Vives MV. M-current modulation of cortical slow oscillations: Network dynamics and computational modeling. PLoS Comput Biol 2023; 19:e1011246. [PMID: 37405991 DOI: 10.1371/journal.pcbi.1011246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 06/06/2023] [Indexed: 07/07/2023] Open
Abstract
The slow oscillation is a synchronized network activity expressed by the cortical network in slow wave sleep and under anesthesia. Waking up requires a transition from this synchronized brain state to a desynchronized one. Cholinergic innervation is critical for the transition from slow-wave-sleep to wakefulness, and muscarinic action is largely exerted through the muscarinic-sensitive potassium current (M-current) block. We investigated the dynamical impact of blocking the M-current on slow oscillations, both in cortical slices and in a cortical network computational model. Blocking M-current resulted in an elongation of Up states (by four times) and in a significant firing rate increase, reflecting an increased network excitability, albeit no epileptiform discharges occurred. These effects were replicated in a biophysical cortical model, where a parametric reduction of the M-current resulted in a progressive elongation of Up states and firing rate. All neurons, and not only those modeled with M-current, increased their firing rates due to network recurrency. Further increases in excitability induced even longer Up states, approaching the microarousals described in the transition towards wakefulness. Our results bridge an ionic current with network modulation, providing a mechanistic insight into network dynamics of awakening.
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Affiliation(s)
- Leonardo Dalla Porta
- Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | | | - Maria V Sanchez-Vives
- Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- ICREA, Passeig Lluís Companys, Barcelona, Spain
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3
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Chen KJ, Yoshimura R, Edmundo CA, Truong TM, Civelli O, Alachkar A, Abbott GW. Behavioral and neuro-functional consequences of eliminating the KCNQ3 GABA binding site in mice. Front Mol Neurosci 2023; 16:1192628. [PMID: 37305551 PMCID: PMC10248464 DOI: 10.3389/fnmol.2023.1192628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/09/2023] [Indexed: 06/13/2023] Open
Abstract
Voltage-gated potassium (Kv) channels formed by α subunits KCNQ2-5 are important in regulating neuronal excitability. We previously found that GABA directly binds to and activates channels containing KCNQ3, challenging the traditional understanding of inhibitory neurotransmission. To investigate the functional significance and behavioral role of this direct interaction, mice with a mutated KCNQ3 GABA binding site (Kcnq3-W266L) were generated and subjected to behavioral studies. Kcnq3-W266L mice exhibited distinctive behavioral phenotypes, of which reduced nociceptive and stress responses were profound and sex-specific. In female Kcnq3-W266L mice, the phenotype was shifted towards more nociceptive effects, while in male Kcnq3-W266L mice, it was shifted towards the stress response. In addition, female Kcnq3-W266L mice exhibited lower motor activity and reduced working spatial memory. The neuronal activity in the lateral habenula and visual cortex was altered in the female Kcnq3-W266L mice, suggesting that GABAergic activation of KCNQ3 in these regions may play a role in the regulation of the responses. Given the known overlap between the nociceptive and stress brain circuits, our data provide new insights into a sex-dependent role of KCNQ3 in regulating neural circuits involved in nociception and stress, via its GABA binding site. These findings identify new targets for effective treatments for neurological and psychiatric conditions such as pain and anxiety.
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Affiliation(s)
- Kiki J. Chen
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
| | - Ryan Yoshimura
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Clarissa Adriana Edmundo
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
| | - Tri Minh Truong
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
| | - Olivier Civelli
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
| | - Amal Alachkar
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
- UC Irvine Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, United States
- Institute for Genomics and Bioinformatics, School of Information and Computer Sciences, University of California, Irvine, Irvine, CA, United States
| | - Geoffrey W. Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
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4
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Nuñez E, Jones F, Muguruza-Montero A, Urrutia J, Aguado A, Malo C, Bernardo-Seisdedos G, Domene C, Millet O, Gamper N, Villarroel A. Redox regulation of K V7 channels through EF3 hand of calmodulin. eLife 2023; 12:e81961. [PMID: 36803414 PMCID: PMC9988260 DOI: 10.7554/elife.81961] [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: 07/18/2022] [Accepted: 02/10/2023] [Indexed: 02/22/2023] Open
Abstract
Neuronal KV7 channels, important regulators of cell excitability, are among the most sensitive proteins to reactive oxygen species. The S2S3 linker of the voltage sensor was reported as a site-mediating redox modulation of the channels. Recent structural insights reveal potential interactions between this linker and the Ca2+-binding loop of the third EF-hand of calmodulin (CaM), which embraces an antiparallel fork formed by the C-terminal helices A and B, constituting the calcium responsive domain (CRD). We found that precluding Ca2+ binding to the EF3 hand, but not to EF1, EF2, or EF4 hands, abolishes oxidation-induced enhancement of KV7.4 currents. Monitoring FRET (Fluorescence Resonance Energy Transfer) between helices A and B using purified CRDs tagged with fluorescent proteins, we observed that S2S3 peptides cause a reversal of the signal in the presence of Ca2+ but have no effect in the absence of this cation or if the peptide is oxidized. The capacity of loading EF3 with Ca2+ is essential for this reversal of the FRET signal, whereas the consequences of obliterating Ca2+ binding to EF1, EF2, or EF4 are negligible. Furthermore, we show that EF3 is critical for translating Ca2+ signals to reorient the AB fork. Our data are consistent with the proposal that oxidation of cysteine residues in the S2S3 loop relieves KV7 channels from a constitutive inhibition imposed by interactions between the EF3 hand of CaM which is crucial for this signaling.
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Affiliation(s)
| | - Frederick Jones
- School of Biomedical Sciences, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
| | | | | | | | | | | | - Carmen Domene
- Department of Chemistry, University of BathBathUnited Kingdom
- Department of Chemistry, University of OxfordOxfordUnited Kingdom
| | - Oscar Millet
- Protein Stability and Inherited Disease Laboratory, CIC bioGUNEDerioSpain
| | - Nikita Gamper
- School of Biomedical Sciences, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
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5
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Musella S, Carotenuto L, Iraci N, Baroli G, Ciaglia T, Nappi P, Basilicata MG, Salviati E, Barrese V, Vestuto V, Pignataro G, Pepe G, Sommella E, Di Sarno V, Manfra M, Campiglia P, Gomez-Monterrey I, Bertamino A, Taglialatela M, Ostacolo C, Miceli F. Beyond Retigabine: Design, Synthesis, and Pharmacological Characterization of a Potent and Chemically Stable Neuronal Kv7 Channel Activator with Anticonvulsant Activity. J Med Chem 2022; 65:11340-11364. [PMID: 35972998 PMCID: PMC9421656 DOI: 10.1021/acs.jmedchem.2c00911] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
![]()
Neuronal Kv7 channels represent important pharmacological
targets
for hyperexcitability disorders including epilepsy. Retigabine is
the prototype Kv7 activator clinically approved for seizure treatment;
however, severe side effects associated with long-term use have led
to its market discontinuation. Building upon the recently described
cryoEM structure of Kv7.2 complexed with retigabine and on previous
structure–activity relationship studies, a small library of
retigabine analogues has been designed, synthesized, and characterized
for their Kv7 opening ability using both fluorescence- and electrophysiology-based
assays. Among all tested compounds, 60 emerged as a potent
and photochemically stable neuronal Kv7 channel activator. Compared
to retigabine, compound 60 displayed a higher brain/plasma
distribution ratio, a longer elimination half-life, and more potent
and effective anticonvulsant effects in an acute seizure model in
mice. Collectively, these data highlight compound 60 as
a promising lead compound for the development of novel Kv7 activators
for the treatment of hyperexcitability diseases.
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Affiliation(s)
- Simona Musella
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Lidia Carotenuto
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Nunzio Iraci
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale Ferdinando Stagno d'Alcontres 31, Messina 98166, Italy
| | - Giulia Baroli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Tania Ciaglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Piera Nappi
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | | | - Emanuela Salviati
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Vincenzo Barrese
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Vincenzo Vestuto
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Giuseppe Pignataro
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Giacomo Pepe
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Eduardo Sommella
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Veronica Di Sarno
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Michele Manfra
- Department of Science, University of Basilicata, Via dell'Ateneo Lucano 10, Potenza 85100, Italy
| | - Pietro Campiglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Isabel Gomez-Monterrey
- Department of Pharmacy, University Federico II of Naples, Via D. Montesano 49, Naples 80131, Italy
| | - Alessia Bertamino
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Maurizio Taglialatela
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Carmine Ostacolo
- Department of Pharmacy, University Federico II of Naples, Via D. Montesano 49, Naples 80131, Italy
| | - Francesco Miceli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
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6
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Abstract
KCNQ2 and KCNQ3 channels are associated with multiple neurodevelopmental disorders and are also therapeutic targets for neurological and neuropsychiatric diseases. For more than two decades, it has been thought that most KCNQ channels in the brain are either KCNQ2/3 or KCNQ3/5 heteromers. Here, we investigated the potential heteromeric compositions of KCNQ2-containing channels. We applied split-intein protein trans-splicing to form KCNQ2/5 tandems and coexpressed these with and without KCNQ3. Unexpectedly, we found that KCNQ2/5 tandems form functional channels independent of KCNQ3 in heterologous cells. Using mass spectrometry, we went on to demonstrate that KCNQ2 associates with KCNQ5 in native channels in the brain, even in the absence of KCNQ3. Additionally, our functional heterologous expression data are consistent with the formation of KCNQ2/3/5 heteromers. Thus, the composition of KCNQ channels is more diverse than has been previously recognized, necessitating a re-examination of the genotype/phenotype relationship of KCNQ2 pathogenic variants.
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7
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Chen J, Ye H, Zhang J, Li A, Ni Y. Pathogenesis of seizures and epilepsy after stroke. ACTA EPILEPTOLOGICA 2022. [DOI: 10.1186/s42494-021-00068-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
AbstractStroke is the most frequent cause of secondary epilepsy in the elderly. The incidence of cerebral stroke is increasing with the extension of life expectancy, and the prevalence of post-stroke epilepsy (PSE) is rising. There are various seizure types after stroke, and the occurrence of epilepsy is closely related to the type and location of stroke. Moreover, the clinical treatment of post-stroke epilepsy is difficult, which increases the risk of disability and death, and affects the prognosis and quality of life of patients. Now seizure and epilepsy after stroke is more and more get the attention of the medical profession, has been more and more researchers have devoted to seizures after stroke and PSE clinical and basic research, and hope to get a scientific and unified guideline, to give timely and effective treatment, but the exact pathophysiologic mechanism has not yet formed a unified conclusion. It has been found that ion channels, neurotransmitters, proliferation of glial cells, genetics and other factors are involved in the occurrence and development of PSE. In this review, we discuss the pathogenesis of early-onset epileptic seizures and late-onset epilepsy after stroke, in order to provide a basis for clinicians to understand the disease, and expect to provide ideas for future exploration.
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8
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Kv7.4 Channels Regulate Potassium Permeability in Neuronal Mitochondria. Biochem Pharmacol 2022; 197:114931. [DOI: 10.1016/j.bcp.2022.114931] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 01/08/2023]
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9
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Aiba I, Noebels JL. Kcnq2/Kv7.2 controls the threshold and bi-hemispheric symmetry of cortical spreading depolarization. Brain 2021; 144:2863-2878. [PMID: 33768249 PMCID: PMC8536937 DOI: 10.1093/brain/awab141] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/22/2021] [Accepted: 03/20/2021] [Indexed: 12/03/2022] Open
Abstract
Spreading depolarization is a slowly propagating wave of massive cellular depolarization associated with acute brain injury and migraine aura. Genetic studies link depolarizing molecular defects in Ca2+ flux, Na+ current in interneurons, and glial Na+-K+ ATPase with spreading depolarization susceptibility, emphasizing the important roles of synaptic activity and extracellular ionic homeostasis in determining spreading depolarization threshold. In contrast, although gene mutations in voltage-gated potassium ion channels that shape intrinsic membrane excitability are frequently associated with epilepsy susceptibility, it is not known whether epileptogenic mutations that regulate membrane repolarization also modify spreading depolarization threshold and propagation. Here we report that the Kcnq2/Kv7.2 potassium channel subunit, frequently mutated in developmental epilepsy, is a spreading depolarization modulatory gene with significant control over the seizure-spreading depolarization transition threshold, bi-hemispheric cortical expression, and diurnal temporal susceptibility. Chronic DC-band cortical EEG recording from behaving conditional Kcnq2 deletion mice (Emx1cre/+::Kcnq2flox/flox) revealed spontaneous cortical seizures and spreading depolarization. In contrast to the related potassium channel deficient model, Kv1.1-KO mice, spontaneous cortical spreading depolarizations in Kcnq2 cKO mice are tightly coupled to the terminal phase of seizures, arise bilaterally, and are observed predominantly during the dark phase. Administration of the non-selective Kv7.2 inhibitor XE991 to Kv1.1-KO mice partly reproduced the Kcnq2 cKO-like spreading depolarization phenotype (tight seizure coupling and bilateral symmetry) in these mice, indicating that Kv7.2 currents can directly and actively modulate spreading depolarization properties. In vitro brain slice studies confirmed that Kcnq2/Kv7.2 depletion or pharmacological inhibition intrinsically lowers the cortical spreading depolarization threshold, whereas pharmacological Kv7.2 activators elevate the threshold to multiple depolarizing and hypometabolic spreading depolarization triggers. Together these results identify Kcnq2/Kv7.2 as a distinctive spreading depolarization regulatory gene, and point to spreading depolarization as a potentially significant pathophysiological component of KCNQ2-linked epileptic encephalopathy syndromes. Our results also implicate KCNQ2/Kv7.2 channel activation as a potential adjunctive therapeutic target to inhibit spreading depolarization incidence.
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Affiliation(s)
- Isamu Aiba
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jeffrey L Noebels
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
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10
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Wen JY, Zhang J, Chen S, Chen Y, Zhang Y, Ma ZY, Zhang F, Xie WM, Fan YF, Duan JS, Chen ZW. Endothelium-derived hydrogen sulfide acts as a hyperpolarizing factor and exerts neuroprotective effects via activation of large-conductance Ca 2+ -activated K + channels. Br J Pharmacol 2021; 178:4155-4175. [PMID: 34216027 DOI: 10.1111/bph.15607] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/15/2021] [Accepted: 06/18/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Endothelium-derived hyperpolarizing factor (EDHF) has been suggested as a therapeutic target for vascular protection against ischaemic brain injury. However, the molecular entity of EDHF and its action on neurons remains unclear. This study was undertaken to demonstrate whether the hydrogen sulfide (H2 S) acts as EDHF and exerts neuroprotective effect via large-conductance Ca2+ -activated K+ (BKCa /KCa 1.1) channels. EXPERIMENTAL APPROACH The whole-cell patch-clamp technology was used to record the changes of BKCa currents in rat neurons induced by EDHF. The cerebral ischaemia/reperfusion model of mice and oxygen-glucose deprivation/reoxygenation (OGD/R) model of neurons were used to explore the neuroprotection of EDHF by activating BKCa channels in these neurons. KEY RESULTS Increases of BKCa currents and membrane hyperpolarization in hippocampal neurons induced by EDHF could be markedly inhibited by BKCa channel inhibitor iberiotoxin or endothelial H2 S synthase inhibitor propargylglycine. The H2 S donor, NaHS-induced BKCa current and membrane hyperpolarization in neurons were also inhibited by iberiotoxin, suggesting that H2 S acts as EDHF and activates the neuronal BKCa channels. Besides, we found that the protective effect of endothelium-derived H2 S against mice cerebral ischaemia/reperfusion injury was disrupted by iberiotoxin. Importantly, the inhibitory effect of NaHS or BKCa channel opener on OGD/R-induced neuron injury and the increment of intracellular Ca2+ level could be inhibited by iberiotoxin but enhanced by co-application with L-type but not T-type calcium channel inhibitor. CONCLUSION AND IMPLICATIONS Endothelium-derived H2 S acts as EDHF and exerts neuroprotective effects via activating the BKCa channels and then inhibiting the T-type calcium channels in hippocampal neurons.
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Affiliation(s)
- Ji-Yue Wen
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jie Zhang
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Shuo Chen
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Ye Chen
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Yang Zhang
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Zi-Yao Ma
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Fang Zhang
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Wei-Ming Xie
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Yi-Fei Fan
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jing-Si Duan
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhi-Wu Chen
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
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11
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Boscia F, Elkjaer ML, Illes Z, Kukley M. Altered Expression of Ion Channels in White Matter Lesions of Progressive Multiple Sclerosis: What Do We Know About Their Function? Front Cell Neurosci 2021; 15:685703. [PMID: 34276310 PMCID: PMC8282214 DOI: 10.3389/fncel.2021.685703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 05/23/2021] [Indexed: 12/19/2022] Open
Abstract
Despite significant advances in our understanding of the pathophysiology of multiple sclerosis (MS), knowledge about contribution of individual ion channels to axonal impairment and remyelination failure in progressive MS remains incomplete. Ion channel families play a fundamental role in maintaining white matter (WM) integrity and in regulating WM activities in axons, interstitial neurons, glia, and vascular cells. Recently, transcriptomic studies have considerably increased insight into the gene expression changes that occur in diverse WM lesions and the gene expression fingerprint of specific WM cells associated with secondary progressive MS. Here, we review the ion channel genes encoding K+, Ca2+, Na+, and Cl- channels; ryanodine receptors; TRP channels; and others that are significantly and uniquely dysregulated in active, chronic active, inactive, remyelinating WM lesions, and normal-appearing WM of secondary progressive MS brain, based on recently published bulk and single-nuclei RNA-sequencing datasets. We discuss the current state of knowledge about the corresponding ion channels and their implication in the MS brain or in experimental models of MS. This comprehensive review suggests that the intense upregulation of voltage-gated Na+ channel genes in WM lesions with ongoing tissue damage may reflect the imbalance of Na+ homeostasis that is observed in progressive MS brain, while the upregulation of a large number of voltage-gated K+ channel genes may be linked to a protective response to limit neuronal excitability. In addition, the altered chloride homeostasis, revealed by the significant downregulation of voltage-gated Cl- channels in MS lesions, may contribute to an altered inhibitory neurotransmission and increased excitability.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", Naples, Italy
| | - Maria Louise Elkjaer
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Zsolt Illes
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Neurology, Odense University Hospital, Odense, Denmark
| | - Maria Kukley
- Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque Basque Foundation for Science, Bilbao, Spain
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12
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Dwivedi D, Bhalla US. Physiology and Therapeutic Potential of SK, H, and M Medium AfterHyperPolarization Ion Channels. Front Mol Neurosci 2021; 14:658435. [PMID: 34149352 PMCID: PMC8209339 DOI: 10.3389/fnmol.2021.658435] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/13/2021] [Indexed: 12/19/2022] Open
Abstract
SK, HCN, and M channels are medium afterhyperpolarization (mAHP)-mediating ion channels. The three channels co-express in various brain regions, and their collective action strongly influences cellular excitability. However, significant diversity exists in the expression of channel isoforms in distinct brain regions and various subcellular compartments, which contributes to an equally diverse set of specific neuronal functions. The current review emphasizes the collective behavior of the three classes of mAHP channels and discusses how these channels function together although they play specialized roles. We discuss the biophysical properties of these channels, signaling pathways that influence the activity of the three mAHP channels, various chemical modulators that alter channel activity and their therapeutic potential in treating various neurological anomalies. Additionally, we discuss the role of mAHP channels in the pathophysiology of various neurological diseases and how their modulation can alleviate some of the symptoms.
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Affiliation(s)
- Deepanjali Dwivedi
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bengaluru, India.,Department of Neurobiology, Harvard Medical School, Boston, MA, United States.,Stanley Center at the Broad, Cambridge, MA, United States
| | - Upinder S Bhalla
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bengaluru, India
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13
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Borgini M, Mondal P, Liu R, Wipf P. Chemical modulation of Kv7 potassium channels. RSC Med Chem 2021; 12:483-537. [PMID: 34046626 PMCID: PMC8128042 DOI: 10.1039/d0md00328j] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/01/2020] [Indexed: 01/10/2023] Open
Abstract
The rising interest in Kv7 modulators originates from their ability to evoke fundamental electrophysiological perturbations in a tissue-specific manner. A large number of therapeutic applications are, in part, based on the clinical experience with two broad-spectrum Kv7 agonists, flupirtine and retigabine. Since precise molecular structures of human Kv7 channel subtypes in closed and open states have only very recently started to emerge, computational studies have traditionally been used to analyze binding modes and direct the development of more potent and selective Kv7 modulators with improved safety profiles. Herein, the synthetic and medicinal chemistry of small molecule modulators and the representative biological properties are summarized. Furthermore, new therapeutic applications supported by in vitro and in vivo assay data are suggested.
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Affiliation(s)
- Matteo Borgini
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Pravat Mondal
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Ruiting Liu
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
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14
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Varghese N, Lauritano A, Taglialatela M, Tzingounis AV. KCNQ3 is the principal target of retigabine in CA1 and subicular excitatory neurons. J Neurophysiol 2021; 125:1440-1449. [PMID: 33729829 DOI: 10.1152/jn.00564.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Retigabine is a first-in-class potassium channel opener approved for patients with epilepsy. Unfortunately, several side effects have limited its use in clinical practice, overshadowing its beneficial effects. Multiple studies have shown that retigabine acts by enhancing the activity of members of the voltage-gated KCNQ (Kv7) potassium channel family, particularly the neuronal KCNQ channels KCNQ2-KCNQ5. However, it is currently unknown whether retigabine's action in neurons is mediated by all KCNQ neuronal channels or by only a subset. This knowledge is necessary to elucidate retigabine's mechanism of action in the central nervous system and its adverse effects and to design more effective and selective retigabine analogs. In this study, we show that the action of retigabine in excitatory neurons strongly depends on the presence of KCNQ3 channels. Deletion of Kcnq3 severely limited the ability of retigabine to reduce neuronal excitability in mouse CA1 and subiculum excitatory neurons. In addition, we report that in the absence of KCNQ3 channels, retigabine can enhance CA1 pyramidal neuron activity, leading to a greater number of action potentials and reduced spike frequency adaptation; this finding further supports a key role of KCNQ3 channels in mediating the action of retigabine. Our work provides new insight into the action of retigabine in forebrain neurons, clarifying retigabine's action in the nervous system.NEW & NOTEWORTHY Retigabine has risen to prominence as a first-in-class potassium channel opener approved by the Food and Drug Administration, with potential for treating multiple neurological disorders. Here, we demonstrate that KCNQ3 channels are the primary target of retigabine in excitatory neurons, as deleting these channels greatly diminishes the effect of retigabine in pyramidal neurons. Our data provide the first indication that retigabine controls neuronal firing properties primarily through KCNQ3 channels.
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Affiliation(s)
- Nissi Varghese
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut
| | - Anna Lauritano
- Department of Neuroscience, University of Naples Federico II, Naples, Italy
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15
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Zhang D, Men H, Zhang L, Gao X, Wang J, Li L, Zhu Q, Zhang H, Jia Z. Inhibition of M/K v7 Currents Contributes to Chloroquine-Induced Itch in Mice. Front Mol Neurosci 2020; 13:105. [PMID: 32694980 PMCID: PMC7339983 DOI: 10.3389/fnmol.2020.00105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 05/20/2020] [Indexed: 01/31/2023] Open
Abstract
M/Kv7 potassium channels play a key role in regulation of neuronal excitability. Modulation of neuronal excitability of primary sensory neurons determines the itch sensation induced by a variety of itch-causing substances including chloroquine (CQ). In the present study, we demonstrate that suppression of M/Kv7 channel activity contributes to generation of itch in mice. CQ enhances excitability of the primary sensory neurons through inhibiting M/Kv7 potassium currents in a Ca2+ influx-dependent manner. Specific M/Kv7 channel opener retigabine (RTG) or tannic acid (TA) not only reverses the CQ-induced enhancement of neuronal excitability but also suppresses the CQ-induced itch behavior. Systemic application of RTG or TA also significantly inhibits the itch behavior induced by a variety of pruritogens. Taken together, our findings provide novel insight into the molecular basis of CQ-induced itch sensation in mammals that can be applied to the development of strategies to mitigate itch behavior.
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Affiliation(s)
- Dong Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China.,Department of Anesthesiology, Hebei General Hospital, Shijiazhuang, China
| | - Hongchao Men
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China.,Department of Anesthesiology, Hebei General Hospital, Shijiazhuang, China
| | - Ludi Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
| | - Xiangxin Gao
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
| | - Jingjing Wang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
| | - Leying Li
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
| | - Qiaoying Zhu
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
| | - Hailin Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
| | - Zhanfeng Jia
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.,Center for Innovative Drug Research and Evaluation, Institute of Medical Science and Health, Hebei Medical University, Shijiazhuang, China.,The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Shijiazhuang, China.,The Key Laboratory of New Drug Pharmacology and Toxicology, Shijiazhuang, China
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16
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Mondejar-Parreño G, Perez-Vizcaino F, Cogolludo A. Kv7 Channels in Lung Diseases. Front Physiol 2020; 11:634. [PMID: 32676036 PMCID: PMC7333540 DOI: 10.3389/fphys.2020.00634] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/18/2020] [Indexed: 12/23/2022] Open
Abstract
Lung diseases constitute a global health concern causing disability. According to WHO in 2016, respiratory diseases accounted for 24% of world population mortality, the second cause of death after cardiovascular diseases. The Kv7 channels family is a group of voltage-dependent K+ channels (Kv) encoded by KCNQ genes that are involved in various physiological functions in numerous cell types, especially, cardiac myocytes, smooth muscle cells, neurons, and epithelial cells. Kv7 channel α-subunits are regulated by KCNE1–5 ancillary β-subunits, which modulate several characteristics of Kv7 channels such as biophysical properties, cell-location, channel trafficking, and pharmacological sensitivity. Kv7 channels are mainly expressed in two large groups of lung tissues: pulmonary arteries (PAs) and bronchial tubes. In PA, Kv7 channels are expressed in pulmonary artery smooth muscle cells (PASMCs); while in the airway (trachea, bronchus, and bronchioles), Kv7 channels are expressed in airway smooth muscle cells (ASMCs), airway epithelial cells (AEPs), and vagal airway C-fibers (VACFs). The functional role of Kv7 channels may vary depending on the cell type. Several studies have demonstrated that the impairment of Kv7 channel has a strong impact on pulmonary physiology contributing to the pathophysiology of different respiratory diseases such as cystic fibrosis, asthma, chronic obstructive pulmonary disease, chronic coughing, lung cancer, and pulmonary hypertension. Kv7 channels are now recognized as playing relevant physiological roles in many tissues, which have encouraged the search for Kv7 channel modulators with potential therapeutic use in many diseases including those affecting the lung. Modulation of Kv7 channels has been proposed to provide beneficial effects in a number of lung conditions. Therefore, Kv7 channel openers/enhancers or drugs acting partly through these channels have been proposed as bronchodilators, expectorants, antitussives, chemotherapeutics and pulmonary vasodilators.
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Affiliation(s)
- Gema Mondejar-Parreño
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.,Ciber Enfermedades Respiratorias (Ciberes), Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
| | - Francisco Perez-Vizcaino
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.,Ciber Enfermedades Respiratorias (Ciberes), Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
| | - Angel Cogolludo
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.,Ciber Enfermedades Respiratorias (Ciberes), Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
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17
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Vigil FA, Carver CM, Shapiro MS. Pharmacological Manipulation of K v 7 Channels as a New Therapeutic Tool for Multiple Brain Disorders. Front Physiol 2020; 11:688. [PMID: 32636759 PMCID: PMC7317068 DOI: 10.3389/fphys.2020.00688] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 05/27/2020] [Indexed: 12/12/2022] Open
Abstract
K v 7 ("M-type," KCNQ) K+ currents, play dominant roles in controlling neuronal excitability. They act as a "brake" against hyperexcitable states in the central and peripheral nervous systems. Pharmacological augmentation of M current has been developed for controlling epileptic seizures, although current pharmacological tools are uneven in practical usefulness. Lately, however, M-current "opener" compounds have been suggested to be efficacious in preventing brain damage after multiple types of insults/diseases, such as stroke, traumatic brain injury, drug addiction and mood disorders. In this review, we will discuss what is known to date on these efforts and identify gaps in our knowledge regarding the link between M current and therapeutic potential for these disorders. We will outline the preclinical experiments that are yet to be performed to demonstrate the likelihood of success of this approach in human trials. Finally, we also address multiple pharmacological tools available to manipulate different K v 7 subunits and the relevant evidence for translational application in the clinical use for disorders of the central nervous system and multiple types of brain insults. We feel there to be great potential for manipulation of K v 7 channels as a novel therapeutic mode of intervention in the clinic, and that the paucity of existing therapies obligates us to perform further research, so that patients can soon benefit from such therapeutic approaches.
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Affiliation(s)
- Fabio A Vigil
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, United States
| | - Chase M Carver
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, United States
| | - Mark S Shapiro
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, United States
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18
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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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19
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Jaworski T. Control of neuronal excitability by GSK-3beta: Epilepsy and beyond. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118745. [PMID: 32450268 DOI: 10.1016/j.bbamcr.2020.118745] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/07/2020] [Accepted: 05/09/2020] [Indexed: 12/22/2022]
Abstract
Glycogen synthase kinase 3beta (GSK-3β) is an enzyme with a variety of cellular functions in addition to the regulation of glycogen metabolism. In the central nervous system, different intracellular signaling pathways converge on GSK-3β through a cascade of phosphorylation events that ultimately control a broad range of neuronal functions in the development and adulthood. In mice, genetically removing or increasing GSK-3β cause distinct functional and structural neuronal phenotypes and consequently affect cognition. Precise control of GSK-3β activity is important for such processes as neuronal migration, development of neuronal morphology, synaptic plasticity, excitability, and gene expression. Altered GSK-3β activity contributes to aberrant plasticity within neuronal circuits leading to neurological, psychiatric disorders, and neurodegenerative diseases. Therapeutically targeting GSK-3β can restore the aberrant plasticity of neuronal networks at least in animal models of these diseases. Although the complete repertoire of GSK-3β neuronal substrates has not been defined, emerging evidence shows that different ion channels and their accessory proteins controlling excitability, neurotransmitter release, and synaptic transmission are regulated by GSK-3β, thereby supporting mechanisms of synaptic plasticity in cognition. Dysregulation of ion channel function by defective GSK-3β activity sustains abnormal excitability in the development of epilepsy and other GSK-3β-linked human diseases.
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Affiliation(s)
- Tomasz Jaworski
- Laboratory of Animal Models, Nencki Institute of Experimental Biology, Warsaw, Poland.
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20
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Wu Z, Li L, Xie F, Xu G, Dang D, Yang Q. Enhancing KCNQ Channel Activity Improves Neurobehavioral Recovery after Spinal Cord Injury. J Pharmacol Exp Ther 2020; 373:72-80. [PMID: 31969383 DOI: 10.1124/jpet.119.264010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/17/2020] [Indexed: 01/08/2023] Open
Abstract
Spinal cord injury (SCI) usually leads to acute neuronal death and delayed secondary degeneration, resulting in sensory dysfunction, paralysis, and chronic pain. Excessive excitation is one of the critical factors leading to secondary neural damage initiated by various insults. KCNQ/Kv7 channels are highly expressed in spinal neurons and axons and play an important role in controlling their excitability. Enhancing KCNQ channel activity by using its specific opener retigabine could thus be a plausible treatment strategy to reduce the pathology after SCI. We produced contusive SCI at T10 in adult male rats, which then received 10 consecutive days' treatment with retigabine or vehicle starting 3 hours or 3 days after contusion. Two different concentrations and two different delivery methods were applied. Delivery of retigabine via Alzet osmotic pumps, but not intraperitoneal injections 3 hours after contusion, promoted recovery of locomotor function. Remarkably, retigabine delivery in both methods significantly attenuated the development of mechanical stimuli-induced hyperreflexia and spontaneous pain; however, no significant difference in the thermal threshold was observed. Although retigabine delivered 3 days after contusion significantly attenuated the development of mechanical hypersensitivity and spontaneous pain, the locomotor function is not improved by the delayed treatments. Finally, we found that early application of retigabine attenuates the inflammatory activity in the spinal cord and increases the survival of white matter after SCI. Our results suggest that decreasing neuronal excitability by targeting KCNQ/Kv7 channels at acute stage aids the recovery of locomotor function and attenuates the development of neuropathic pain after SCI. SIGNIFICANCE STATEMENT: Several pharmacological interventions have been proposed for spinal cord injury (SCI) treatment, but none have been shown to be both effective and safe in clinical trials. Necrotic neuronal death and chronic pain are often the cost of pathological neural excitation after SCI. We show that early, brief application of retigabine could aid locomotor and sensory neurobehavioral recovery after SCI, supporting the use of this drug in the clinic to promote motor and sensory function in patients with SCI.
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Affiliation(s)
- Zizhen Wu
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland (Z.W.); Department of Integrative Biology and Pharmacology, McGovern Medical School at UT Health, Houston, Texas (L.L., F.X.); Department of Critical Medicine, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China (F.X.); and Department of Neuroscience, Cell Biology and Anatomy at University of Texas Medical Branch, Galveston, Texas (G.X., D.D., Q.Y.)
| | - Lin Li
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland (Z.W.); Department of Integrative Biology and Pharmacology, McGovern Medical School at UT Health, Houston, Texas (L.L., F.X.); Department of Critical Medicine, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China (F.X.); and Department of Neuroscience, Cell Biology and Anatomy at University of Texas Medical Branch, Galveston, Texas (G.X., D.D., Q.Y.)
| | - Fuhua Xie
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland (Z.W.); Department of Integrative Biology and Pharmacology, McGovern Medical School at UT Health, Houston, Texas (L.L., F.X.); Department of Critical Medicine, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China (F.X.); and Department of Neuroscience, Cell Biology and Anatomy at University of Texas Medical Branch, Galveston, Texas (G.X., D.D., Q.Y.)
| | - Guoying Xu
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland (Z.W.); Department of Integrative Biology and Pharmacology, McGovern Medical School at UT Health, Houston, Texas (L.L., F.X.); Department of Critical Medicine, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China (F.X.); and Department of Neuroscience, Cell Biology and Anatomy at University of Texas Medical Branch, Galveston, Texas (G.X., D.D., Q.Y.)
| | - Danny Dang
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland (Z.W.); Department of Integrative Biology and Pharmacology, McGovern Medical School at UT Health, Houston, Texas (L.L., F.X.); Department of Critical Medicine, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China (F.X.); and Department of Neuroscience, Cell Biology and Anatomy at University of Texas Medical Branch, Galveston, Texas (G.X., D.D., Q.Y.)
| | - Qing Yang
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland (Z.W.); Department of Integrative Biology and Pharmacology, McGovern Medical School at UT Health, Houston, Texas (L.L., F.X.); Department of Critical Medicine, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China (F.X.); and Department of Neuroscience, Cell Biology and Anatomy at University of Texas Medical Branch, Galveston, Texas (G.X., D.D., Q.Y.)
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21
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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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22
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Alkuraishy HM, Al-Gareeb AI, Waheed HJ. Lipoprotein-Associated Phospholipase A2 is Linked with Poor Cardio-Metabolic Profile in Patients with Ischemic Stroke: A Study of Effects of Statins. J Neurosci Rural Pract 2019; 9:496-503. [PMID: 30271040 PMCID: PMC6126307 DOI: 10.4103/jnrp.jnrp_97_18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Objectives The objective of the study is to investigate the effects of statins on the lipoprotein-associated phospholipase A2 (Lp-PLA2) mass in patients with ischemic stroke. Materials and Methods A total number of 59 patient ages 43-69 years with cerebral stroke compared to 39 healthy controls that matching the age and body weight. The patients were divided into 32 patients on statins therapy assigned as statins users and 27 patients, not on statins therapy assigned as nonstatins users. Anthropometric and biochemical measurements were done including lipid profile and inflammatory biomarkers. Results Stroke patients on statins therapy showed a comparable low of Lp-PLA (29.82 ± 3.19 IU/mL) to nonstatins user stroke patients (15.58 ± 5.73 IU/mL). Lp-PLA2 mass levels were positively correlated with body mass index, blood pressure changes, total cholesterol, triglyceride, and very low-density lipoprotein and stroke risk (SR) percentage. Conclusions Patients on statins with ischemic stroke had low levels of Lp-PLA2 mass levels compared to nonstatins user with ischemic stroke. Lp-PLA2 mass levels were higher in men than women and correlated with lipid profile and SR in patients with ischemic stroke.
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Affiliation(s)
- Hayder M Alkuraishy
- Department of Clinical Pharmacology and Therapeutic, Medical Faculty College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | - Ali I Al-Gareeb
- Department of Clinical Pharmacology and Therapeutic, Medical Faculty College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | - Huda J Waheed
- Department of Clinical Pharmacology and Therapeutic, Medical Faculty College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
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Du X, Gao H, Jaffe D, Zhang H, Gamper N. M-type K + channels in peripheral nociceptive pathways. Br J Pharmacol 2018; 175:2158-2172. [PMID: 28800673 PMCID: PMC5980636 DOI: 10.1111/bph.13978] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 07/17/2017] [Accepted: 08/03/2017] [Indexed: 12/22/2022] Open
Abstract
Pathological pain is a hyperexcitability disorder. Since the excitability of a neuron is set and controlled by a complement of ion channels it expresses, in order to understand and treat pain, we need to develop a mechanistic insight into the key ion channels controlling excitability within the mammalian pain pathways and how these ion channels are regulated and modulated in various physiological and pathophysiological settings. In this review, we will discuss the emerging data on the expression in pain pathways, functional role and modulation of a family of voltage-gated K+ channels called 'M channels' (KCNQ, Kv 7). M channels are increasingly recognized as important players in controlling pain signalling, especially within the peripheral somatosensory system. We will also discuss the therapeutic potential of M channels as analgesic drug targets. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc/.
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Affiliation(s)
- Xiaona Du
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
| | - Haixia Gao
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
- School of Biomedical Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsUK
| | - David Jaffe
- Department of Biology, UTSA Neurosciences InstituteUniversity of Texas at San AntonioSan AntonioTXUSA
| | - Hailin Zhang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
| | - Nikita Gamper
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
- School of Biomedical Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsUK
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24
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Barrese V, Stott JB, Greenwood IA. KCNQ-Encoded Potassium Channels as Therapeutic Targets. Annu Rev Pharmacol Toxicol 2018; 58:625-648. [DOI: 10.1146/annurev-pharmtox-010617-052912] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - Iain A. Greenwood
- Vascular Biology Research Centre, Molecular and Clinical Sciences Institute, St George's, University of London, London, SW17 0RE, United Kingdom;, ,
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25
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Abstract
Oncotic cell death or oncosis represents a major mechanism of cell death in ischaemic stroke, occurring in many central nervous system (CNS) cell types including neurons, glia and vascular endothelial cells. In stroke, energy depletion causes ionic pump failure and disrupts ionic homeostasis. Imbalance between the influx of Na+ and Cl- ions and the efflux of K+ ions through various channel proteins and transporters creates a transmembrane osmotic gradient, with ensuing movement of water into the cells, resulting in cell swelling and oncosis. Oncosis is a key mediator of cerebral oedema in ischaemic stroke, contributing directly through cytotoxic oedema, and indirectly through vasogenic oedema by causing vascular endothelial cell death and disruption of the blood-brain barrier (BBB). Hence, inhibition of uncontrolled ionic flux represents a novel and powerful strategy in achieving neuroprotection in stroke. In this review, we provide an overview of oncotic cell death in the pathology of stroke. Importantly, we summarised the therapeutically significant pathways of water, Na+, Cl- and K+ movement across cell membranes in the CNS and their respective roles in the pathobiology of stroke.
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26
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Photothrombotic Stroke as a Model of Ischemic Stroke. Transl Stroke Res 2017; 9:437-451. [DOI: 10.1007/s12975-017-0593-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/14/2017] [Accepted: 11/24/2017] [Indexed: 12/20/2022]
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27
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Gao F, Wang CT, Chen C, Guo X, Yang LH, Ma XC, Han JF. Effect of Hypokalemia on Functional Outcome at 3 Months Post-Stroke Among First-Ever Acute Ischemic Stroke Patients. Med Sci Monit 2017; 23:2825-2832. [PMID: 28600907 PMCID: PMC5475375 DOI: 10.12659/msm.902464] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Background Hypokalemia has been confirmed to be a predictor of adverse cardiovascular and renal outcomes. There is a paucity of studies focusing on the potential connection between the serum K+ level and the outcome after acute ischemic stroke (AIS). This study investigated whether hypokalemia in the acute stroke stage contributes to worse functional outcome in AIS patients. Material/Methods This retrospective cohort study included consecutive patients with first-ever AIS admitted between June 2015 and March 2016. Patients were divided into 2 groups: hypokalemia (K+ <3.5 mmol/L) and normokalemia (3.5 mmol/L ≤K+ ≤5.5 mmol/L). Primary outcome measure was poor outcome at 3 months (modified Rankin scale >2). Univariate and multivariate logistic regression analyses were used to assess the association between hypokalemia and poor outcome. Receiver operating curve (ROC) analysis was performed to determine the optimal cutoff point of serum K+ level for predicting poor outcome. Results The percent of patients with poor outcome at 3 months was higher in the hypokalemic group (62.9%) than in the normokalemic group (45.5%). Hypokalemic patients tended to have lower fasting glucose at admission, lower Glasgow coma scale score, and longer time from symptom onset to treatment compared with normokalemic patients. Hypokalemia was associated with poor outcome at 3 months after adjusting for potential confounders (odds ratio=2.42, 95% confidence interval=1.21–4.86, P=0.013). ROC analysis showed that the optimal threshold for serum K+ level was 3.7 mmol/L. Conclusions Hypokalemia at the initial admission is associated with poor prognosis at 3 months in first-ever AIS patients.
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Affiliation(s)
- Fan Gao
- Clinical Research Center, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China (mainland)
| | - Cheng-Tai Wang
- Department of Neurology, Baoji City Chinese Medicine Hospital, Baoji, Shaanxi, China (mainland)
| | - Chen Chen
- Department of Neurology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China (mainland)
| | - Xing Guo
- Department of Pharmacy, The First Affiliated Hospital of Xi'an Medical University, Xi'an, Shaanxi, China (mainland)
| | - Li-Hong Yang
- Clinical Research Center, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China (mainland)
| | - Xian-Cang Ma
- Clinical Research Center, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China (mainland).,Department of Psychiatry, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China (mainland)
| | - Jian-Feng Han
- Department of Neurology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China (mainland)
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28
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Targeting a Potassium Channel/Syntaxin Interaction Ameliorates Cell Death in Ischemic Stroke. J Neurosci 2017; 37:5648-5658. [PMID: 28483976 DOI: 10.1523/jneurosci.3811-16.2017] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/25/2017] [Accepted: 05/01/2017] [Indexed: 12/12/2022] Open
Abstract
The voltage-gated K+ channel Kv2.1 has been intimately linked with neuronal apoptosis. After ischemic, oxidative, or inflammatory insults, Kv2.1 mediates a pronounced, delayed enhancement of K+ efflux, generating an optimal intracellular environment for caspase and nuclease activity, key components of programmed cell death. This apoptosis-enabling mechanism is initiated via Zn2+-dependent dual phosphorylation of Kv2.1, increasing the interaction between the channel's intracellular C-terminus domain and the SNARE (soluble N-ethylmaleimide-sensitive factor activating protein receptor) protein syntaxin 1A. Subsequently, an upregulation of de novo channel insertion into the plasma membrane leads to the critical enhancement of K+ efflux in damaged neurons. Here, we investigated whether a strategy designed to interfere with the cell death-facilitating properties of Kv2.1, specifically its interaction with syntaxin 1A, could lead to neuroprotection following ischemic injury in vivo The minimal syntaxin 1A-binding sequence of Kv2.1 C terminus (C1aB) was first identified via a far-Western peptide screen and used to create a protherapeutic product by conjugating C1aB to a cell-penetrating domain. The resulting peptide (TAT-C1aB) suppressed enhanced whole-cell K+ currents produced by a mutated form of Kv2.1 mimicking apoptosis in a mammalian expression system, and protected cortical neurons from slow excitotoxic injury in vitro, without influencing NMDA-induced intracellular calcium responses. Importantly, intraperitoneal administration of TAT-C1aB in mice following transient middle cerebral artery occlusion significantly reduced ischemic stroke damage and improved neurological outcome. These results provide strong evidence that targeting the proapoptotic function of Kv2.1 is an effective and highly promising neuroprotective strategy.SIGNIFICANCE STATEMENT Kv2.1 is a critical regulator of apoptosis in central neurons. It has not been determined, however, whether the cell death-enabling function of this K+ channel can be selectively targeted to improve neuronal survival following injury in vivo The experiments presented here demonstrate that the cell death-specific role of Kv2.1 can be uniquely modulated to provide neuroprotection in an animal model of acute ischemic stroke. We thus reveal a novel therapeutic strategy for neurological disorders that are accompanied by Kv2.1-facilitated forms of cell death.
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29
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Isbrandt D. A mechanistic link between glia and neuronal excitability in acute neuroinflammation. J Physiol 2017; 595:603-604. [PMID: 28145018 DOI: 10.1113/jp273252] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Dirk Isbrandt
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,University of Cologne, Cologne, Germany
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30
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Zhou X, Zhuang F, Li H, Zheng K, Hong Z, Feng W, Zhou W, Chen J. Calmodulin regulates KCNQ2 function in epilepsy. Am J Transl Res 2016; 8:5610-5618. [PMID: 28078031 PMCID: PMC5209511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/08/2016] [Indexed: 06/06/2023]
Abstract
Epilepsy is linked to mutations in KCNQ channels. KCNQ channels including KCNQ2 and KCNQ3 are enriched in neurons, regulating action potential generation and modulation. Here, we showed that properties of KCNQ2 channel in rat hippocampal cultured neurons are regulated by ubiquitous calcium sensor calmodulin. We analyzed calmodulin function on the KCNQ2 channel in both HEK293 cells and neurons. We used shRNAs to suppress expression of calmodulin protein. On the other hand, we used cDNA to over-express calmodulin in HEK293 and neuron cells. In wild type and mis-sense mutations of KCNQ2 proteins, calmodulin over-expression enhanced outward K+ current and decreased neuronal activity. Meanwhile, calmodulin knockdown reduced KCNQ2 current and increased neuronal activity, showing that hippocampal neuronal excitability is regulated by expression level of calmodulin protein. Our data suggest that calmodulin performs a major function in regulating KCNQ2 properties via direct binding to KCNQ2 protein, indicating that calmodulin could be a target of as gene therapy in epilepsy.
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Affiliation(s)
- Xuhong Zhou
- The Second People’s Hospital of Huai’anHuai’an, China
| | - Fei Zhuang
- Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
| | - Hong Li
- Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
| | - Kun Zheng
- Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
| | - Ze Hong
- Department of Pediatrics, Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
| | - Weijing Feng
- Department of Pediatrics, Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
| | - Wendi Zhou
- Department of Pediatrics, Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
| | - Jian Chen
- Department of Pediatrics, Huai’an First People’s Hospital, Nanjing Medical UniversityHuai’an, China
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31
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Wang J, Wu C, Peng J, Patel N, Huang Y, Gao X, Aljarallah S, Eubanks JH, McDonald R, Zhang L. Early-Onset Convulsive Seizures Induced by Brain Hypoxia-Ischemia in Aging Mice: Effects of Anticonvulsive Treatments. PLoS One 2015; 10:e0144113. [PMID: 26630670 PMCID: PMC4668036 DOI: 10.1371/journal.pone.0144113] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 11/15/2015] [Indexed: 12/27/2022] Open
Abstract
Aging is associated with an increased risk of seizures/epilepsy. Stroke (ischemic or hemorrhagic) and cardiac arrest related brain injury are two major causative factors for seizure development in this patient population. With either etiology, seizures are a poor prognostic factor. In spite of this, the underlying pathophysiology of seizure development is not well understood. In addition, a standardized treatment regimen with anticonvulsants and outcome assessments following treatment has yet to be established for these post-ischemic seizures. Previous studies have modeled post-ischemic seizures in adult rodents, but similar studies in aging/aged animals, a group that mirrors a higher risk elderly population, remain sparse. Our study therefore aimed to investigate early-onset seizures in aging animals using a hypoxia-ischemia (HI) model. Male C57 black mice 18-20-month-old underwent a unilateral occlusion of the common carotid artery followed by a systemic hypoxic episode (8% O2 for 30 min). Early-onset seizures were detected using combined behavioral and electroencephalographic (EEG) monitoring. Brain injury was assessed histologically at different times post HI. Convulsive seizures were observed in 65% of aging mice post-HI but not in control aging mice following either sham surgery or hypoxia alone. These seizures typically occurred within hours of HI and behaviorally consisted of jumping, fast running, barrel-rolling, and/or falling (loss of the righting reflex) with limb spasms. No evident discharges during any convulsive seizures were seen on cortical-hippocampal EEG recordings. Seizure development was closely associated with acute mortality and severe brain injury on brain histological analysis. Intra-peritoneal injections of lorazepam and fosphenytoin suppressed seizures and improved survival but only when applied prior to seizure onset and not after. These findings together suggest that seizures are a major contributing factor to acute mortality in aging mice following severe brain ischemia and that early anticonvulsive treatment may prevent seizure genesis and improve overall outcomes.
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Affiliation(s)
- Justin Wang
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Chiping Wu
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Jessie Peng
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Nisarg Patel
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Yayi Huang
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Xiaoxing Gao
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Salman Aljarallah
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
- Neurology Unit, Department of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - James H. Eubanks
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Surgery (Neurosurgery), University of Toronto, Toronto, Ontario, Canada
| | - Robert McDonald
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Liang Zhang
- Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
- Departments of Medicine (Neurology), University of Toronto, Toronto, Ontario, Canada
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32
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Sucher NJ, Carles MC. A pharmacological basis of herbal medicines for epilepsy. Epilepsy Behav 2015; 52:308-18. [PMID: 26074183 DOI: 10.1016/j.yebeh.2015.05.012] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 05/06/2015] [Indexed: 01/25/2023]
Abstract
Epilepsy is the most common chronic neurological disease, affecting about 1% of the world's population during their lifetime. Most people with epilepsy can attain a seizure-free life upon treatment with antiepileptic drugs (AEDs). Unfortunately, seizures in up to 30% do not respond to treatment. It is estimated that 90% of people with epilepsy live in developing countries, and most of them receive no drug treatment for the disease. This treatment gap has motivated investigations into the effects of plants that have been used by traditional healers all over the world to treat seizures. Extracts of hundreds of plants have been shown to exhibit anticonvulsant activity in phenotypic screens performed in experimental animals. Some of those extracts appear to exhibit anticonvulsant efficacy similar to that of synthetic AEDs. Dozens of plant-derived chemical compounds have similarly been shown to act as anticonvulsants in various in vivo and in vitro assays. To a significant degree, anticonvulsant effects of plant extracts can be attributed to widely distributed flavonoids, (furano)coumarins, phenylpropanoids, and terpenoids. Flavonoids and coumarins have been shown to interact with the benzodiazepine site of the GABAA receptor and various voltage-gated ion channels, which are targets of synthetic AEDs. Modulation of the activity of ligand-gated and voltage-gated ion channels provides an explanatory basis of the anticonvulsant effects of plant secondary metabolites. Many complex extracts and single plant-derived compounds exhibit antiinflammatory, neuroprotective, and cognition-enhancing activities that may be beneficial in the treatment of epilepsy. Thus, botanicals provide a base for target-oriented antiepileptic drug discovery and development. In the future, preclinical work should focus on the characterization of the effects of plant extracts and plant-derived compounds on well-defined targets rather than on phenotypic screening using in vivo animal models of acute seizures. At the same time, available data provide ample justification for clinical studies with selected standardized botanical extracts and plant-derived compounds. This article is part of a Special Issue entitled "Botanicals for Epilepsy".
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Affiliation(s)
- Nikolaus J Sucher
- Science Department, Roxbury Community College, MA, USA; FLAS, Northern Essex Community College, MA, USA; Biology Department, Salem State University, MA, USA.
| | - Maria C Carles
- Science Department, Roxbury Community College, MA, USA; FLAS, Northern Essex Community College, MA, USA; Biology Department, Salem State University, MA, USA
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An automated task for the training and assessment of distal forelimb function in a mouse model of ischemic stroke. J Neurosci Methods 2015; 258:16-23. [PMID: 26484787 DOI: 10.1016/j.jneumeth.2015.10.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/02/2015] [Accepted: 10/09/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND Behavioral models relevant to stroke research seek to capture important aspects of motor skills typically impaired in human patients, such as coordination of distal musculature. Such models may focus on mice since many genetic tools are available for use only in that species and since the training and behavioral demands of mice can differ from rats even for superficially similar behavioral readouts. However, current mouse assays are time consuming to train and score, especially in a manner producing continuous quantification. An automated assay of mouse forelimb function may provide advantages for quantification and speed, and may be useful for many applications including stroke research. NEW METHOD We present an automated assay of distal forelimb function. In this task, mice reach forward, grip and pull an isometric handle with a prescribed force. The apparatus partially automates the training process so that mice can be trained quickly and simultaneously. RESULTS Using this apparatus, it is possible to measure long-lasting impairment in success rate, force pulled, latency to pull, and latency to success up to 22 weeks following photothrombotic cortical strokes in mice. COMPARISON WITH EXISTING METHOD(S) This assessment measures forelimb function as do pellet reach tasks, but it utilizes a different motion and provides automatic measures that can ease and augment the research process. CONCLUSIONS This high-throughput behavioral assay can detect long-lasting motor impairments, eliminates the need for subjective scoring, and produces a rich, continuous data set from which many aspects of the reach and grasp motion can be automatically extracted.
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Barrese V, Taglialatela M, Greenwood IA, Davidson C. Protective role of Kv7 channels in oxygen and glucose deprivation-induced damage in rat caudate brain slices. J Cereb Blood Flow Metab 2015; 35:1593-600. [PMID: 25966943 PMCID: PMC4640310 DOI: 10.1038/jcbfm.2015.83] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 03/09/2015] [Accepted: 04/09/2015] [Indexed: 11/09/2022]
Abstract
Ischemic stroke can cause striatal dopamine efflux that contributes to cell death. Since Kv7 potassium channels regulate dopamine release, we investigated the effects of their pharmacological modulation on dopamine efflux, measured by fast cyclic voltammetry (FCV), and neurotoxicity, in Wistar rat caudate brain slices undergoing oxygen and glucose deprivation (OGD). The Kv7 activators retigabine and ICA27243 delayed the onset, and decreased the peak level of dopamine efflux induced by OGD; and also decreased OGD-induced damage measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining. Retigabine also reduced OGD-induced necrotic cell death evaluated by lactate dehydrogenase activity assay. The Kv7 blocker linopirdine increased OGD-evoked dopamine efflux and OGD-induced damage, and attenuated the effects of retigabine. Quantitative-PCR experiments showed that OGD caused an ~6-fold decrease in Kv7.2 transcript, while levels of mRNAs encoding for other Kv7 subunits were unaffected; western blot experiments showed a parallel reduction in Kv7.2 protein levels. Retigabine also decreased the peak level of dopamine efflux induced by L-glutamate, and attenuated the loss of TTC staining induced by the excitotoxin. These results suggest a role for Kv7.2 in modulating ischemia-evoked caudate damage.
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Affiliation(s)
- Vincenzo Barrese
- Division of Biomedical Sciences, St George's University of London, London, UK.,Department of Neuroscience Reproductive Sciences and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Maurizio Taglialatela
- Department of Neuroscience Reproductive Sciences and Odontostomatology, University of Naples Federico II, Naples, Italy.,Department of Medicine and Health Science, University of Molise, Campobasso, Italy
| | - Iain A Greenwood
- Division of Biomedical Sciences, St George's University of London, London, UK
| | - Colin Davidson
- Division of Biomedical Sciences, St George's University of London, London, UK
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