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Mayo S, Gómez-Manjón I, Marco-Hernández AV, Fernández-Martínez FJ, Camacho A, Martínez F. N-Type Ca Channel in Epileptic Syndromes and Epilepsy: A Systematic Review of Its Genetic Variants. Int J Mol Sci 2023; 24:6100. [PMID: 37047073 PMCID: PMC10094502 DOI: 10.3390/ijms24076100] [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: 02/20/2023] [Revised: 03/20/2023] [Accepted: 03/22/2023] [Indexed: 04/14/2023] Open
Abstract
N-type voltage-gated calcium channel controls the release of neurotransmitters from neurons. The association of other voltage-gated calcium channels with epilepsy is well-known. The association of N-type voltage-gated calcium channels and pain has also been established. However, the relationship between this type of calcium channel and epilepsy has not been specifically reviewed. Therefore, the present review systematically summarizes existing publications regarding the genetic associations between N-type voltage-dependent calcium channel and epilepsy.
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Affiliation(s)
- Sonia Mayo
- Genetics and Inheritance Research Group, Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041 Madrid, Spain
- Department of Genetics, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
| | - Irene Gómez-Manjón
- Genetics and Inheritance Research Group, Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041 Madrid, Spain
- Department of Genetics, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
| | - Ana Victoria Marco-Hernández
- Neuropediatric Unit, Hospital Universitario Doctor Peset, 46017 Valencia, Spain
- Translational Research in Genetics, Instituto de Investigación Sanitaria La Fe, 46026 Valencia, Spain
| | - Francisco Javier Fernández-Martínez
- Genetics and Inheritance Research Group, Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041 Madrid, Spain
- Department of Genetics, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
| | - Ana Camacho
- Division of Pediatric Neurology, Department of Neurology, Hospital Universitario 12 de Octubre, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Francisco Martínez
- Translational Research in Genetics, Instituto de Investigación Sanitaria La Fe, 46026 Valencia, Spain
- Genomic Unit, Instituto de Investigación Sanitaria La Fe, 46026 Valencia, Spain
- Genetics Unit, Hospital Universitario y Politecnico La Fe, 46026 Valencia, Spain
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Zheng JJ, Zhang TY, Liu HT, Huang ZX, Teng JM, Deng JX, Zhong JG, Qian X, Sheng XW, Ding JQ, He SQ, Zhao X, Ji WD, Qi DF, Li W, Zhang M. Cytisine Exerts an Anti-Epileptic Effect via α7nAChRs in a Rat Model of Temporal Lobe Epilepsy. Front Pharmacol 2021; 12:706225. [PMID: 34248648 PMCID: PMC8263902 DOI: 10.3389/fphar.2021.706225] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/09/2021] [Indexed: 11/13/2022] Open
Abstract
Background and Purpose: Temporal lobe epilepsy (TLE) is a common chronic neurological disease that is often invulnerable to anti-epileptic drugs. Increasing data have demonstrated that acetylcholine (ACh) and cholinergic neurotransmission are involved in the pathophysiology of epilepsy. Cytisine, a full agonist of α7 nicotinic acetylcholine receptors (α7nAChRs) and a partial agonist of α4β2nAChRs, has been widely applied for smoking cessation and has shown neuroprotection in neurological diseases. However, whether cytisine plays a role in treating TLE has not yet been determined. Experimental Approach: In this study, cytisine was injected intraperitoneally into pilocarpine-induced epileptic rats for three weeks. Alpha-bungarotoxin (α-bgt), a specific α7nAChR antagonist, was used to evaluate the mechanism of action of cytisine. Rats were assayed for the occurrence of seizures and cognitive function by video surveillance and Morris water maze. Hippocampal injuries and synaptic structure were assessed by Nissl staining and Golgi staining. Furthermore, levels of glutamate, γ-aminobutyric acid (GABA), ACh, and α7nAChRs were measured. Results: Cytisine significantly reduced seizures and hippocampal damage while improving cognition and inhibiting synaptic remodeling in TLE rats. Additionally, cytisine decreased glutamate levels without altering GABA levels, and increased ACh levels and α7nAChR expression in the hippocampi of TLE rats. α-bgt antagonized the above-mentioned effects of cytisine treatment. Conclusion and Implications: Taken together, these findings indicate that cytisine exerted an anti-epileptic and neuroprotective effect in TLE rats via activation of α7nAChRs, which was associated with a decrease in glutamate levels, inhibition of synaptic remodeling, and improvement of cholinergic transmission in the hippocampus. Hence, our findings not only suggest that cytisine represents a promising anti-epileptic drug, but provides evidence of α7nAChRs as a novel therapeutic target for TLE.
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Affiliation(s)
- Jing-Jun Zheng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China.,Department of Pharmacy, Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Teng-Yue Zhang
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Hong-Tao Liu
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Ze-Xin Huang
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jing-Mei Teng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jing-Xian Deng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jia-Gui Zhong
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xu Qian
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Xin-Wen Sheng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Ji-Qiang Ding
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Shu-Qiao He
- Department of Pharmacy, Maoming People's Hospital, Maoming, China
| | - Xin Zhao
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Wei-Dong Ji
- Center for Translational Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - De-Feng Qi
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hop-ital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou, China
| | - Wei Li
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Mei Zhang
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
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Upregulated Connexin 43 Induced by Loss-of-Functional S284L-Mutant α4 Subunit of Nicotinic ACh Receptor Contributes to Pathomechanisms of Autosomal Dominant Sleep-Related Hypermotor Epilepsy. Pharmaceuticals (Basel) 2020; 13:ph13040058. [PMID: 32235384 PMCID: PMC7243124 DOI: 10.3390/ph13040058] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 03/26/2020] [Accepted: 03/27/2020] [Indexed: 01/07/2023] Open
Abstract
To study the pathomechanism and pathophysiology of autosomal dominant sleep-related hypermotor epilepsy (ADSHE), this study determined functional abnormalities of glutamatergic transmission in the thalamocortical motor pathway, from the reticular thalamic nucleus (RTN), motor thalamic nuclei (MoTN) tosecondary motor cortex (M2C) associated with the S286L-mutant α4β2-nicotinic acetylcholine receptor (nAChR) and the connexin43 (Cx43) hemichannel of transgenic rats bearing the rat S286L-mutant Chrna4 gene (S286L-TG), which corresponds to the human S284L-mutant CHRNA4 gene using multiprobe microdialysis, primary cultured astrocytes and a Simple Western system. Expression of Cx43 in the M2C plasma membrane fraction of S286L-TG was upregulated compared with wild-type rats. Subchronic nicotine administration decreased Cx43 expression of wild-type, but did not affect that of S286L-TG; however, zonisamide (ZNS) decreased Cx43 in both wild-type and S286L-TG. Primary cultured astrocytes of wild-type were not affected by subchronic administration of nicotine but was decreased by ZNS. Upregulated Cx43 enhanced glutamatergic transmission during both resting and hyperexcitable stages in S286L-TG. Furthermore, activation of glutamatergic transmission associated with upregulated Cx43 reinforced the prolonged Cx43 hemichannel activation. Subchronic administration of therapeutic-relevant doses of ZNS compensated the upregulation of Cx43 and prolonged reinforced activation of Cx43 hemichannel induced by physiological hyperexcitability during the non-rapid eye movement phase of sleep. The present results support the primary pathomechanisms and secondary pathophysiology of ADSHE seizures of patients with S284L-mutation.
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Fukuyama K, Fukuzawa M, Shiroyama T, Okada M. Pathomechanism of nocturnal paroxysmal dystonia in autosomal dominant sleep-related hypermotor epilepsy with S284L-mutant α4 subunit of nicotinic ACh receptor. Biomed Pharmacother 2020; 126:110070. [PMID: 32169758 DOI: 10.1016/j.biopha.2020.110070] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/29/2020] [Accepted: 03/03/2020] [Indexed: 12/17/2022] Open
Abstract
To study the pathomechanism and pathophysiology of nocturnal paroxysmal dystonia of autosomal dominant sleep-related hypermotor epilepsy (ADSHE), this study determined functional abnormalities in thalamic hyperdirect pathway from reticular thalamic nucleus (RTN), motor thalamic nuclei (MoTN), subthalamic nucleus (STN) to substantia nigra pars reticulata (SNr) of transgenic rats (S286L-TG) bearing S286 L missense mutation of rat Chrna4 gene, which corresponds to the S284 L mutation in the human CHRNA4 gene. The activation of α4β2-nAChR in the RTN increased GABA release in MoTN resulting in reduced glutamatergic transmission in thalamic hyperdirect pathway of wild-type. Contrary to wild-type, activation of S286L-mutant α4β2-nAChR (loss-of-function) in the RTN relatively enhanced glutamatergic transmission in thalamic hyperdirect pathway of S286L-TG via impaired GABAergic inhibition in intra-thalamic (RTN-MoTN) pathway. These functional abnormalities in glutamatergic transmission in hyperdirect pathway contribute to the pathomechanism of electrophysiologically negative nocturnal paroxysmal dystonia of S286L-TG. Therapeutic-relevant concentration of zonisamide (ZNS) inhibited the glutamatergic transmission in the hyperdirect pathway via activation of group II metabotropic glutamate receptor (II-mGluR) in MoTN and STN. The present results suggest that S286L-mutant α4β2-nAChR induces GABAergic disinhibition in intra-thalamic (RTN-MoTN) pathway and hyperactivation of glutamatergic transmission in thalamic hyperdirect pathway (MoTN-STN-SNr), possibly contributing to the pathomechanism of nocturnal paroxysmal dystonia of ADSHE patients with S284L mutant CHRNA4. Inhibition of glutamatergic transmission in thalamic hyperdirect pathway induced by ZNS via activation of II-mGluR may be involved, at least partially, in ZNS-sensitive nocturnal paroxysmal dystonia of ADSHE patients with S284L mutation.
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Affiliation(s)
- Kouji Fukuyama
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of Medicine, Mie University, Tsu, Mie 514-8507, Japan.
| | - Masashi Fukuzawa
- Department of Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki. 036-8560, Japan.
| | - Takashi Shiroyama
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of Medicine, Mie University, Tsu, Mie 514-8507, Japan.
| | - Motohiro Okada
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of Medicine, Mie University, Tsu, Mie 514-8507, Japan.
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Carbamazepine Attenuates Astroglial L-Glutamate Release Induced by Pro-Inflammatory Cytokines via Chronically Activation of Adenosine A 2A Receptor. Int J Mol Sci 2019; 20:ijms20153727. [PMID: 31366130 PMCID: PMC6695599 DOI: 10.3390/ijms20153727] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 12/18/2022] Open
Abstract
Carbamazepine (CBZ) binds adenosine receptors, but detailed effects of CBZ on astroglial transmission associated with adenosine receptor still need to be clarified. To clarify adenosinergic action of CBZ on astroglial transmission, primary cultured astrocytes were acutely or chronically treated with CBZ, proinflammatory cytokines (interferon γ (IFNγ) and tumor necrosis factor α (TNFα)), and adenosine A2A receptor (A2AR) agonist (CGS21680). IFNγ and TNFα increased basal, adenophostin-A (AdA)-evoked, and 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)propanoic acid (AMPA)-evoked astroglial L-glutamate releases. In physiological condition, CGS21680 increased basal astroglial L-glutamate release but glutamate transporter inhibition prevented this CGS21680 action. CBZ did not affect basal release, whereas glutamate transporter inhibition generated CBZ-induced glutamate release. Furthermore, AdA-evoked and AMPA-evoked releases were inhibited by CBZ but were unaffected by CGS21680. Contrary to physiological condition, chronic administrations of IFNγ and TNFα enhanced basal, AdA-, and AMPA-evoked releases, whereas IFNγ and TNFα decreased and increased CGS21680-evoked releases via modulation A2AR expression. Both chronic administration of CGS21680 and CBZ suppressed astroglial L-glutamate release responses induced by chronic cytokine exposer. Especifically, chronic administration of CBZ and CGS21680 prevented the reduction and elevation of A2AR expression by respective IFNγ and TNFα. These findings suggest that A2AR agonistic effects of CBZ contribute to chronic prevention of pathomechanisms developments of several neuropsychiatric disorders associated with proinflammatory cytokines.
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Amantadine Combines Astroglial System Xc - Activation with Glutamate/NMDA Receptor Inhibition. Biomolecules 2019; 9:biom9050191. [PMID: 31108896 PMCID: PMC6572554 DOI: 10.3390/biom9050191] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 05/11/2019] [Accepted: 05/15/2019] [Indexed: 01/06/2023] Open
Abstract
A glutamate/NMDA receptor (NMDA-R) antagonist, amantadine (AMA) exhibits a broad spectrum of clinically important properties, including antiviral, antiparkinsonian, neuroprotective, neuro-reparative and cognitive-enhancing effects. However, both clinical and pre-clinical studies have demonstrated that noncompetitive NMDA-R antagonists induce severe schizophrenia-like cognitive deficits. Therefore, this study aims to clarify the clinical discrepancy between AMA and noncompetitive NMDA-R antagonists by comparing the effects of AMA with those of a noncompetitive NMDA-R antagonist, MK801, on rat tripartite glutamatergic synaptic transmission using microdialysis and primary cultured astrocytes. Microdialysis study demonstrated that the stimulatory effects of AMA on L-glutamate release differed from those of MK801 in the globus pallidus, entorhinal cortex and entopeduncular nucleus. The stimulatory effect of AMA on L-glutamate release was modulated by activation of cystine/glutamate antiporter (Sxc). Primary cultured astrocytes study demonstrated that AMA also enhanced glutathione synthesis via Sxc activation. Furthermore, carbon-monoxide induced damage of the astroglial glutathione synthesis system was repaired by AMA but not MK801. Additionally, glutamate/AMPA receptor (AMPA-R) antagonist, perampanel enhanced the protective effects of AMA. The findings of microdialysis and cultured astrocyte studies suggest that a combination of Sxc activation with inhibitions of ionotropic glutamate receptors contributes to neuroprotective, neuro-reparative and cognitive-enhancing activities that can mitigate several neuropsychiatric disorders.
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Ueno SI, Saiki S, Fujimaki M, Takeshige-Amano H, Hatano T, Oyama G, Ishikawa KI, Yamaguchi A, Nojiri S, Akamatsu W, Hattori N. Zonisamide Administration Improves Fatty Acid β-Oxidation in Parkinson's Disease. Cells 2018; 8:cells8010014. [PMID: 30597973 PMCID: PMC6356654 DOI: 10.3390/cells8010014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/20/2018] [Accepted: 12/25/2018] [Indexed: 12/03/2022] Open
Abstract
Although many experimental studies have shown the favorable effects of zonisamide on mitochondria using models of Parkinson’s disease (PD), the influence of zonisamide on metabolism in PD patients remains unclear. To assess metabolic status under zonisamide treatment in PD, we performed a pilot study using a comprehensive metabolome analysis. Plasma samples were collected for at least one year from 30 patients with PD: 10 without zonisamide medication and 20 with zonisamide medication. We performed comprehensive metabolome analyses of plasma with capillary electrophoresis time-of-flight mass spectrometry and liquid chromatography time-of-flight mass spectrometry. We also measured disease severity using Hoehn and Yahr (H&Y) staging and the Unified Parkinson’s Disease Rating Scale (UPDRS) motor section, and analyzed blood chemistry. In PD with zonisamide treatment, 15 long-chain acylcarnitines (LCACs) tended to be increased, of which four (AC(12:0), AC(12:1)-1, AC(16:1), and AC(16:2)) showed statistical significance. Of these, two LCACs (AC(16:1) and AC(16:2)) were also identified by partial least squares analysis. There was no association of any LCAC with age, disease severity, levodopa daily dose, or levodopa equivalent dose. Because an upregulation of LCACs implies improvement of mitochondrial β-oxidation, zonisamide might be beneficial for mitochondrial β-oxidation, which is suppressed in PD.
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Affiliation(s)
- Shin-Ichi Ueno
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Shinji Saiki
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Motoki Fujimaki
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Haruka Takeshige-Amano
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Taku Hatano
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Genko Oyama
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Kei-Ichi Ishikawa
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
- Center for Genomic and Regenerative Medicine, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Akihiro Yamaguchi
- Center for Genomic and Regenerative Medicine, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Shuko Nojiri
- Medical Technology Innovation Center, Juntendo University, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Wado Akamatsu
- Center for Genomic and Regenerative Medicine, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Nobutaka Hattori
- Department of Neurology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan.
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Eslicarbazepine acetate reduces trigeminal nociception: Possible role of adrenergic, cholinergic and opioid receptors. Life Sci 2018; 214:167-175. [DOI: 10.1016/j.lfs.2018.10.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 10/09/2018] [Accepted: 10/26/2018] [Indexed: 01/31/2023]
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Yabuki Y, Matsuo K, Izumi H, Haga H, Yoshida T, Wakamori M, Kakei A, Sakimura K, Fukuda T, Fukunaga K. Pharmacological properties of SAK3, a novel T-type voltage-gated Ca 2+ channel enhancer. Neuropharmacology 2017; 117:1-13. [PMID: 28093211 DOI: 10.1016/j.neuropharm.2017.01.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 12/27/2016] [Accepted: 01/12/2017] [Indexed: 11/30/2022]
Abstract
T-type voltage-gated Ca2+ channels (T-VGCCs) function in the pathophysiology of epilepsy, pain and sleep. However, their role in cognitive function remains unclear. We previously reported that the cognitive enhancer ST101, which stimulates T-VGCCs in rat cortical slices, was a potential Alzheimer's disease therapeutic. Here, we introduce a more potent T-VGCC enhancer, SAK3 (ethyl 8'-methyl-2',4-dioxo-2-(piperidin-1-yl)-2'H-spiro[cyclopentane-1,3'-imidazo [1,2-a]pyridin]-2-ene-3-carboxylate), and characterize its pharmacological properties in brain. Based on whole cell patch-clamp analysis, SAK3 (0.01-10 nM) significantly enhanced Cav3.1 currents in neuro2A cells ectopically expressing Cav3.1. SAK3 (0.1-10 nM nM) also enhanced Cav3.3 but not Cav3.2 currents in the transfected cells. Notably, Cav3.1 and Cav3.3 T-VGCCs were localized in cholinergic neurve systems in hippocampus and in the medial septum. Indeed, acute oral administration of SAK3 (0.5 mg/kg, p.o.), but not ST101 (0.5 mg/kg, p.o.) significantly enhanced acetylcholine (ACh) release in the hippocampal CA1 region of naïve mice. Moreover, acute SAK3 (0.5 mg/kg, p.o.) administration significantly enhanced hippocampal ACh levels in olfactory-bulbectomized (OBX) mice, rescuing impaired memory-related behaviors. Treatment of OBX mice with the T-VGCC-specific blocker NNC 55-0396 (12.5 mg/kg, i.p.) antagonized both enhanced ACh release and memory improvements elicited by SAK3 administration. We also observed that SAK3-induced ACh releases were significantly blocked in the hippocampus from Cav3.1 knockout (KO) mice. These findings suggest overall that T-VGCCs play a key role in cognition by enhancing hippocampal ACh release and that the cognitive enhancer SAK3 could be a candidate therapeutic in Alzheimer's disease.
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Affiliation(s)
- Yasushi Yabuki
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Kazuya Matsuo
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Hisanao Izumi
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Hidaka Haga
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Takashi Yoshida
- Department of Oral Biology, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Minoru Wakamori
- Department of Oral Biology, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Akikazu Kakei
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, Nagano, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Takaichi Fukuda
- Department of Anatomy and Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kohji Fukunaga
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
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Kim JH, Keum G, Chung H, Nam G. Synthesis and T-type calcium channel-blocking effects of aryl(1,5-disubstituted-pyrazol-3-yl)methyl sulfonamides for neuropathic pain treatment. Eur J Med Chem 2016; 123:665-672. [DOI: 10.1016/j.ejmech.2016.07.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 07/14/2016] [Accepted: 07/18/2016] [Indexed: 11/16/2022]
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11
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Ghasemi M, Hadipour-Niktarash A. Pathologic role of neuronal nicotinic acetylcholine receptors in epileptic disorders: implication for pharmacological interventions. Rev Neurosci 2016; 26:199-223. [PMID: 25565544 DOI: 10.1515/revneuro-2014-0044] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Accepted: 10/16/2014] [Indexed: 12/30/2022]
Abstract
Accumulating evidence suggests that neuronal nicotinic acetylcholine receptors (nAChRs) may play a key role in the pathophysiology of some neurological diseases such as epilepsy. Based on genetic studies in patients with epileptic disorders worldwide and animal models of seizure, it has been demonstrated that nAChR activity is altered in some specific types of epilepsy, including autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) and juvenile myoclonic epilepsy (JME). Neuronal nAChR antagonists also have antiepileptic effects in pre-clinical studies. There is some evidence that conventional antiepileptic drugs may affect neuronal nAChR function. In this review, we re-examine the evidence for the involvement of nAChRs in the pathophysiology of some epileptic disorders, especially ADNFLE and JME, and provide an overview of nAChR antagonists that have been evaluated in animal models of seizure.
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Perkins AE, Fadel JR, Kelly SJ. The effects of postnatal alcohol exposure and galantamine on the context pre-exposure facilitation effect and acetylcholine efflux using in vivo microdialysis. Alcohol 2015; 49:193-205. [PMID: 25837482 DOI: 10.1016/j.alcohol.2015.01.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/05/2015] [Accepted: 01/23/2015] [Indexed: 12/12/2022]
Abstract
Fetal alcohol spectrum disorders (FASD) are characterized by damage to multiple brain regions, including the hippocampus, which is involved in learning and memory. The acetylcholine neurotransmitter system provides major input to the hippocampus and is a possible target of developmental alcohol exposure. Alcohol (3.0 g/kg/day) was administered via intubation to male rat pups (postnatal day [PD] 2-10; ethanol-treated [ET]). Controls received a sham intubation (IC) or no treatment (NC). Acetylcholine efflux was measured using in vivo microdialysis (PD 32-35). ET animals were not different at baseline, but had decreased K(+)/Ca(2+)-induced acetylcholine efflux compared to NC animals and an enhanced acetylcholine response to galantamine (acetylcholinesterase inhibitor; 2.0 mg/kg) compared to both control groups. A separate cohort of animals was tested in the context pre-exposure facilitation effect task (CPFE; PD 30-32) following postnatal alcohol exposure and administration of galantamine (2.0 mg/kg; PD 11-30). Neither chronic galantamine nor postnatal alcohol exposure influenced performance in the CPFE task. Using immunohistochemistry, we found that neither alcohol exposure nor behavioral testing significantly altered the density of vesicular acetylcholine transporter or alpha7 nicotinic acetylcholine receptor in the ventral hippocampus (CA1). In the medial septum, the average number of choline acetyltransferase (ChAT+) cells was increased in ET animals that displayed the context-shock association; there were no changes in IC and NC animals that learned the context-shock association or in any animals that were in the control task that entailed no learning. Taken together, these results indicate that the hippocampal acetylcholine system is significantly disrupted under conditions of pharmacological manipulations (e.g., galantamine) in alcohol-exposed animals. Furthermore, ChAT was up‑regulated in ET animals that learned the CPFE, which may account for their ability to perform this task. In sum, developmental alcohol exposure may disrupt learning and memory in adolescence via a cholinergic mechanism.
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Affiliation(s)
- Amy E Perkins
- Department of Psychology, University of South Carolina, 1512 Pendleton St., Columbia, SC 29208, USA
| | - Jim R Fadel
- Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208, USA
| | - Sandra J Kelly
- Department of Psychology, University of South Carolina, 1512 Pendleton St., Columbia, SC 29208, USA; Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208, USA.
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13
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Powell KL, Cain SM, Snutch TP, O'Brien TJ. Low threshold T-type calcium channels as targets for novel epilepsy treatments. Br J Clin Pharmacol 2015; 77:729-39. [PMID: 23834404 DOI: 10.1111/bcp.12205] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 07/02/2013] [Indexed: 12/21/2022] Open
Abstract
Low voltage-activated T-type calcium channels were originally cloned in the 1990s and much research has since focused on identifying the physiological roles of these channels in health and disease states. T-type calcium channels are expressed widely throughout the brain and peripheral tissues, and thus have been proposed as therapeutic targets for a variety of diseases such as epilepsy, insomnia, pain, cancer and hypertension. This review discusses the literature concerning the role of T-type calcium channels in physiological and pathological processes related to epilepsy. T-type calcium channels have been implicated in pathology of both the genetic and acquired epilepsies and several anti-epileptic drugs (AEDs) in clinical use are known to suppress seizures via inhibition of T-type calcium channels. Despite the fact that more than 15 new AEDs have become clinically available over the past 20 years at least 30% of epilepsy patients still fail to achieve seizure control, and many patients experience unwanted side effects. Furthermore there are no treatments that prevent the development of epilepsy or mitigate the epileptic state once established. Therefore there is an urgent need for the development of new AEDs that are effective in patients with drug resistant epilepsy, are anti-epileptogenic and are better tolerated. We also review the mechanisms of action of the current AEDs with known effects on T-type calcium channels and discuss novel compounds that are being investigated as new treatments for epilepsy.
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Affiliation(s)
- Kim L Powell
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia
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14
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Current understanding of the mechanism of action of the antiepileptic drug lacosamide. Epilepsy Res 2015; 110:189-205. [DOI: 10.1016/j.eplepsyres.2014.11.021] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 11/18/2014] [Accepted: 11/24/2014] [Indexed: 12/22/2022]
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15
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Arranz-Tagarro JA, de los Ríos C, García AG, Padín JF. Recent patents on calcium channel blockers: emphasis on CNS diseases. Expert Opin Ther Pat 2014; 24:959-77. [DOI: 10.1517/13543776.2014.940892] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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16
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Yamamoto Y, Shioda N, Han F, Moriguchi S, Fukunaga K. Novel cognitive enhancer ST101 enhances acetylcholine release in mouse dorsal hippocampus through T-type voltage-gated calcium channel stimulation. J Pharmacol Sci 2013; 121:212-26. [PMID: 23449490 DOI: 10.1254/jphs.12233fp] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
We recently developed a novel cognitive enhancer, ST101 (spiro[imidazo[1,2-a]pyridine-3,2-indan]-2(3H)-one), that activates T-type voltage-gated calcium channels (VGCCs). Here, we address whether T-type VGCC activation with ST101 mediates its cognitive effects in vivo and the relevance of T-type VGCC activation to acetylcholine (ACh) release in the hippocampus. Acute intraperitoneal administration of ST101 (1 mg/kg, i.p.) improved memory-related behaviors in both olfactory bulbectomized (OBX) and scopolamine-treated mice. Effects of ST101 administration were abolished by both intraperitoneal and intracerebroventricular pre-administration of the T-type VGCC inhibitor mibefradil. Acute administration of ST101 enhanced basal and nicotine-induced ACh release in the dorsal hippocampus in both OBX and sham-treated mice. Enhanced ACh release was abolished by infusion with mibefradil (10 μM) but not with the L-type VGCC inhibitor nifedipine (10 μM). As expected, significantly reduced CaMKIIα, PKCα, and ERK phosphorylation was restored by acute ST101 administration in the OBX mouse hippocampal CA1 region. Enhancement of CaMKIIα and PKCα but not ERK phosphorylation was inhibited by mibefradil (20 mg/kg, i.p.) preadministration. Increased CaMKIIα and PKCα phosphorylation was confirmed by increased phosphorylation of GluR1, synapsin I, and NR1. Taken together, stimulation of T-type VGCCs is critical for the enhanced hippocampal ACh release and improved cognitive function seen following ST101 administration.
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Affiliation(s)
- Yui Yamamoto
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
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17
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Abstract
P/Q-type calcium channels are high-voltage-gated calcium channels contributing to vesicle release at synaptic terminals. A number of neurological diseases have been attributed to malfunctioning of P/Q channels, including ataxia, migraine and Alzheimer's disease. To date, only two specific P/Q-type blockers are known: both are peptides deriving from the spider venom of Agelenopsis aperta, ω-agatoxins. Other peptidic calcium channel blockers with activity at P/Q channels are available, albeit with less selectivity. A number of low molecular weight compounds modulate P/Q-type currents with different characteristics, and some exhibit a peculiar bidirectional pattern of modulation. Interestingly, there are a number of therapeutics in clinical use, which also show P/Q channel activity. Because selectivity as well as the exact mode of action is different between all P/Q-type channel modulators, the interpretation of clinical and experimental data is complicated and needs a comprehensive understanding of their target profile. The situation is further complicated by the fact that information on potency varies vastly in the literature, which may be the result of different experimental systems, conditions or the splice variants of the P/Q channel. This review attempts to provide a comprehensive overview of the compounds available that affect the P/Q-type channel and should help with the interpretation of results of in vitro experiments and animal models. It also aims to explain some clinical observations by implementing current knowledge about P/Q channel modulation of therapeutically used non-selective drugs. Chances and challenges of the development of P/Q channel-selective molecules are discussed.
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Affiliation(s)
- V Nimmrich
- Neuroscience Research, GPRD, Abbott, Ludwigshafen, Germany
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18
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Yürekli VA, Gürler S, Nazıroğlu M, Uğuz AC, Koyuncuoğlu HR. Zonisamide attenuates MPP+-induced oxidative toxicity through modulation of Ca2+ signaling and caspase-3 activity in neuronal PC12 cells. Cell Mol Neurobiol 2012; 33:205-12. [PMID: 23229024 DOI: 10.1007/s10571-012-9886-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 09/10/2012] [Indexed: 12/18/2022]
Abstract
Parkinson's disease is an incurable progressive neurological condition caused by a degeneration of dopamine-producing cells characterized by motor and non-motor symptoms. The major mechanisms of the antiepileptic actions of ZNS are inhibition of voltage-gated Na(+) channel, T-type voltage-sensitive Ca(2+) channel, Ca(2+)-induced Ca(2+) releasing system, and neuronal depolarization-induced glutamate release; and enhancement of release of inhibitory neurotransmitters; however, the detailed mechanism of antiparkinsonian effects of ZNS remains to be clarified. We aimed to investigate to the effect of ZNS on the oxidative stress, cell viability, Ca(2+) signaling, and caspase activity that induced by the MPP(+) model of Parkinson's in neuronal PC12 cells. Neuronal PC12 cells were divided into four groups namely, control, ZNS, MPP(+), and ZNS+MPP(+) groups. The dose and duration of ZNS and MPP(+) were determined according to cell viability (MTT) analysis which used to assess the cell viability. The cells in ZNS, MPP(+), and ZNS+MPP(+) groups were incubated for 5 h with 100 μM ZNS, 10 h with 100 μM MPP(+), and 10 h with ZNS and MPP(+), respectively. Lipid peroxidation and cytosolic free Ca(2+) concentrations were higher in the MPP(+) group than in control although their levels were lower in ZNS and the ZNS+MPP(+) groups than in control. Reduced glutathione and glutathione peroxidase values were lower in the MPP(+) group although they were higher in the ZNS and the ZNS+MPP(+) groups than in control. Caspase-3 activity was lower in the ZNS group than in the MPP(+) group. In conclusion, ZNS induced modulator effects on the oxidative stress, intracellular Ca(2+), and the caspase-3 values in an experimental model of Parkinson disease.
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Affiliation(s)
- Vedat Ali Yürekli
- Department of Neurology, Faculty of Medicine, Süleyman Demirel University, Isparta, Turkey
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19
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Siniscalchi A, Gallelli L, De Sarro G, Malferrari G, Santangelo E. Antiepileptic drugs for central post-stroke pain management. Pharmacol Res 2011; 65:171-5. [PMID: 21925602 DOI: 10.1016/j.phrs.2011.09.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 08/28/2011] [Accepted: 09/05/2011] [Indexed: 12/14/2022]
Abstract
Antiepileptic drugs (AEDs) are commonly prescribed for a wide range of disorders other than epilepsy, including both neurological and psychiatric disorders. AEDs play also a role in pharmacological management of neuropathic pain. Central post-stroke pain (CPSP) is a disabling morbidity occurring in 35% of patients with stroke. The pathophysiology of CPSP is not well known but central disinhibition with increased neuronal excitability has been suggested. AEDs include many different drugs acting on pain through several mechanisms, such as reduction of neuronal hyperexcitability. To our knowledge conclusive evidence has not been published yet. The aim of this review is to delineate efficacy and safety of AEDs in CPSP.
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Affiliation(s)
- A Siniscalchi
- Department of Neuroscience, Neurology Division, Annunziata Hospital, Cosenza, Italy
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20
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Rösler TW, Arias-Carrión O, Höglinger GU. Zonisamide: aspects in neuroprotection. Exp Neurol 2010; 224:336-9. [PMID: 20450911 DOI: 10.1016/j.expneurol.2010.04.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 04/27/2010] [Accepted: 04/28/2010] [Indexed: 12/22/2022]
Abstract
Zonisamide is widely used as an antiepileptic drug. Two studies published recently in Experimental Neurology focus on the drug's neuroprotective effect. In the present commentary, we discuss the significance of their findings and aspects of zonisamide in neuroprotection.
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Affiliation(s)
- Thomas W Rösler
- Department of Neurology, Philipps-University, Marburg, Germany
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21
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Siebel AM, Rico EP, Capiotti KM, Piato AL, Cusinato CT, Franco TMA, Bogo MR, Bonan CD. In vitro effects of antiepileptic drugs on acetylcholinesterase and ectonucleotidase activities in zebrafish (Danio rerio) brain. Toxicol In Vitro 2010; 24:1279-84. [PMID: 20362660 DOI: 10.1016/j.tiv.2010.03.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 03/23/2010] [Accepted: 03/28/2010] [Indexed: 01/07/2023]
Abstract
Carbamazepine (CBZ), phenytoin (PHT), and gabapentine (GBP) are classical antiepileptic drugs (AEDs) that act through a variety of mechanisms. We have tested the in vitro effects of CBZ, PHT, and GBP at different concentrations on ectonucleotidase and acetylcholinesterase activities in zebrafish brain. CBZ inhibited ATP hydrolysis at 1000 microM (32%) whereas acetylcholine hydrolysis decreased at 500 microM (25.2%) and 1000 microM (38.7%). PHT increased AMP hydrolysis both at 500 microM (65%) and 1000 microM (64.8%). GBP did not promote any significant changes on ectonucleotidase and acetylcholinesterase activities. These results have shown that CBZ can reduce NTPDase (nucleoside triphosphate diphosphohydrolase) and PHT enhance ecto 5'-nucleotidase activities. Therefore, it is possible to suggest that the AEDs induced-effects on ectonucleotidases are related to enzyme anchorage form. Our findings have also shown that high CBZ concentrations inhibit acetylcholinesterase activity, which can induce an increase of acetylcholine levels. Taken together, these results showed a complex interaction among AEDs, purinergic, and cholinergic systems, providing a better understanding of the AEDs pharmacodynamics.
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Affiliation(s)
- A M Siebel
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Programa de Pós-Graduação em Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul. Avenida Ipiranga, 6681, 90619-900 Porto Alegre, RS, Brazil
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22
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Voltage-gated calcium channels in the etiopathogenesis and treatment of absence epilepsy. ACTA ACUST UNITED AC 2010; 62:245-71. [DOI: 10.1016/j.brainresrev.2009.12.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 12/10/2009] [Accepted: 12/11/2009] [Indexed: 12/21/2022]
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23
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Matar N, Jin W, Wrubel H, Hescheler J, Schneider T, Weiergräber M. Zonisamide block of cloned human T-type voltage-gated calcium channels. Epilepsy Res 2009; 83:224-34. [DOI: 10.1016/j.eplepsyres.2008.11.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Revised: 11/07/2008] [Accepted: 11/11/2008] [Indexed: 01/01/2023]
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24
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Abstract
Antiepileptic drugs (AEDs) suppress seizures by selectively modifying the excitability of neurons and blocking seizure firing with minimal disturbance of nonepileptic activity. All AEDs have been shown to work by at least one of 3 main mechanisms of action: through modulation of voltage-gated ion channels, enhancement of synaptic inhibition, and inhibition of synaptic excitation. Zonisamide is a novel AED that has a broad combination of complementary mechanisms of action, which may offer a clinical advantage over other antiepileptic agents. By altering the fast inactivation threshold of voltage-dependent sodium channels, zonisamide reduces sustained high-frequency repetitive firing of action potentials. Zonisamide also inhibits low-threshold T-type calcium channels in neurons, which may prevent the spread of seizure discharge across cells. In addition, zonisamide is a weak inhibitor of carbonic anhydrase. However, this mechanism is not believed to contribute to the antiepileptic activity of zonisamide. Although zonisamide also seems to alter dopamine, serotonin, and acetylcholine metabolism, it is not clear to what extent these effects on neurotransmitters are involved in the clinical actions of the drug. In addition to these actions, recent evidence suggests that zonisamide may exert neuroprotective actions, independent of its antiepileptic activity. These potential effects may be important in preventing neuronal damage caused by recurrent seizures. Therefore, it seems that the multiple pharmacological actions of zonisamide may contribute to the seizure reductions observed in a wide range of epilepsies and may help to preserve efficacy in individual patients despite possible changes in electrophysiological status.
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Affiliation(s)
- Victor Biton
- Arkansas Epilepsy Program, Little Rock, AR, USA.
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25
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Novelli A, Groppetti A, Rossoni G, Manfredi B, Ferrero-Gutiérrez A, Pérez-Gómez A, Desogus CM, Fernández-Sánchez MT. Nefopam is more potent than carbamazepine for neuroprotection against veratridine in vitro and has anticonvulsant properties against both electrical and chemical stimulation. Amino Acids 2006; 32:323-32. [PMID: 17021653 DOI: 10.1007/s00726-006-0419-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Accepted: 08/09/2006] [Indexed: 11/26/2022]
Abstract
Nefopam (NEF) is a known analgesic that has recently been shown to be effective in controlling both neuropathic pain and convulsions in rodents. In this study we compared nefopam to carbamazepine (CBZ), a reference antiepileptic drug (AED), for their ability to protect cerebellar neuronal cultures from neurodegeneration induced by veratridine (VTD). Furthermore, we tested nefopam for protection against both, maximal electroshock-induced seizures (MES), and isoniazid-induced seizures in mice. Both NEF and CBZ were effective in preventing both signs of excitotoxicity and neurodegeneration following exposure of cultures to 5 microM veratridine for 30 min and 24 h, respectively. Concentrations providing full neuroprotection were 500 microM CBZ and 50 microM NEF, while the concentration providing 50% neuroprotection was 200 microM for CBZ and 20 microM for NEF. Neither NEF nor CBZ reduced excitotoxicity following direct exposure of cultures to glutamate, but CBZ failed to reduce increases in intracellular calcium following stimulation of L-type voltage sensitive calcium channels. In vivo, NEF (20 mg/kg i.p.) significantly reduced MES and fully prevented MES-induced terminal clonus (TC). In comparison, NEF was significantly more effective than CBZ in preventing MES, although both drugs were equally effective against MES-induced TC. Furthermore, nefopam provided protection against isoniazid-induced seizures at doses similar to those protecting against MES.
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Affiliation(s)
- A Novelli
- Department of Psychology/Psychobiology, University of Oviedo, Oviedo, Spain.
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26
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Snutch TP, David LS. T-type calcium channels: an emerging therapeutic target for the treatment of pain. Drug Dev Res 2006. [DOI: 10.1002/ddr.20103] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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27
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Okada M, Yoshida S, Zhu G, Hirose S, Kaneko S. Biphasic actions of topiramate on monoamine exocytosis associated with both soluble N-ethylmaleimide-sensitive factor attachment protein receptors and Ca(2+)-induced Ca(2+)-releasing systems. Neuroscience 2005; 134:233-46. [PMID: 15961239 DOI: 10.1016/j.neuroscience.2005.03.045] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2005] [Revised: 03/26/2005] [Accepted: 03/30/2005] [Indexed: 11/25/2022]
Abstract
To explore the pharmacological mechanisms of topiramate (TPM), we determined the effects of TPM on monoamine (dopamine and serotonin) exocytosis associated with N-ethylmaleimide-sensitive factor attachment protein receptors and Ca(2+)-induced Ca(2+)-releasing systems, including inositol-triphosphate receptor and ryanodine receptor in freely moving rat pre-frontal cortex using in vivo microdialysis. During resting stage, Ca(2+) output from endoplasmic reticulum Ca(2+) store via inositol-triphosphate receptor regulates syntaxin-associated monoamine exocytosis mechanism, whereas during neuronal hyperexcitable stage, Ca(2+) output via ryanodine receptor regulates synaptobrevin-associated monoamine exocytosis mechanism. Basal monoamine releases were increased and decreased by therapeutically relevant and supratherapeutic concentration of TPM, respectively. The therapeutic-relevant concentration of TPM increased Ca(2+)-evoked release concentration-dependently; however, its stimulatory effect was attenuated in the supratherapeutic range. The K(+)-evoked releases were reduced by TPM concentration-dependently (from therapeutic to supratherapeutic ranges). The therapeutic-relevant concentration of TPM-induced elevation of basal release was reduced by cleavage with syntaxin and inhibition of inositol-triphosphate receptor predominantly, by cleavage with SNAP-25 and synaptobrevin weakly, but not by ryanodine receptor inhibitor. The therapeutic-relevant concentration of TPM-induced elevation of Ca(2+)-evoked release was reduced by cleavage with syntaxin and inositol-triphosphate receptor inhibitor selectively. The therapeutic-relevant concentration of TPM-induced reduction of K(+)-evoked monoamine release was abolished by cleavage with synaptobrevin, but was not affected by cleavage with SNAP-25 or synaptobrevin. The stimulatory effect of ryanodine receptor agonist on K(+)-evoked monoamine release was reduced by TPM, whereas that of inositol-triphosphate receptor agonist was not affected by TPM. Therefore, these results indicate that the combination of the effects of TPM on exocytosis mechanisms associated with SNARE and Ca(2+)-induced Ca(2+)-releasing systems, enhancement of inositol-triphosphate receptor/syntaxin and inhibition of ryanodine receptor/synaptobrevin in pre-frontal cortex, may be involved in clinical actions of TPM.
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Affiliation(s)
- M Okada
- Department of Neuropsychiatry, School of Medicine, Hirosaki University, Hirosaki 036-8562, Japan.
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28
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Yoshida S, Okada M, Zhu G, Kaneko S. Effects of zonisamide on neurotransmitter exocytosis associated with ryanodine receptors. Epilepsy Res 2005; 67:153-62. [PMID: 16289509 DOI: 10.1016/j.eplepsyres.2005.10.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 09/30/2005] [Accepted: 10/02/2005] [Indexed: 11/16/2022]
Abstract
To clarify the antiepileptic and neuroprotective actions of zonisamide (ZNS), we determined acute effects of ZNS on exocytosis of GABA and glutamate associated with ryanodine-receptor (Ryr) in rat hippocampus using microdialysis. ZNS increased basal GABA release concentration-dependently without affecting basal glutamate release; however, K(+)-evoked glutamate and GABA releases were reduced by ZNS concentration-dependently. Inhibition of Ryr reduced K(+)-evoked GABA and glutamate releases without affecting their basal releases. Ryanodine affected GABA and glutamate releases biphasic concentration-dependently: lower concentration of ryanodine increased both basal and K(+)-evoked releases of GABA and glutamate, whereas higher concentration reduced them. The therapeutically relevant concentration of ZNS inhibited ryanodine-induced GABA and glutamate releases, and abolished the inflection point in concentration-response curve for ryanodine on neurotransmitter exocytosis. These data suggest that ZNS elevates seizure threshold via enhancement of GABAergic transmission during resting stage. ZNS inhibits propagation of epileptic hyperexcitability and Ryr-associated neuronal damage during neuronal hyperexcitable stage. These demonstrations indicate that the indirect inhibition of Ryr activities by ZNS during neuronal hyperexcitability appear to be involved in the mechanisms of action of antiepileptic and neuroprotective actions of ZNS.
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Affiliation(s)
- Shukuko Yoshida
- Department of Neuropsychiatry, Hirosaki University, Hirosaki 036-8562, Japan
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29
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Huang CW, Ueno S, Okada M, Kaneko S. Zonisamide at clinically relevant concentrations inhibits field EPSP but not presynaptic fiber volley in rat frontal cortex. Epilepsy Res 2005; 67:51-60. [PMID: 16188429 DOI: 10.1016/j.eplepsyres.2005.08.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2005] [Revised: 08/08/2005] [Accepted: 08/10/2005] [Indexed: 11/16/2022]
Abstract
We investigated the effect of Zonisamide (ZNS), a newer anti-epileptic drug, on field potentials and neuropropagation in rat frontal cortex, with the aid of the 64-channel multi-electrode dish (MED64) system. The amplitude and propagation of field potentials were expressed dimensionally in the MED64 system. ZNS (3-100 microM) inhibited the amplitude and propagation of field excitatory postsynaptic potentials (fEPSP) in a concentration dependent manner. In contrast, ZNS could not suppress the amplitude and propagation of the presynaptic fiber volley (PrV) at clinically relevant concentrations (10-30 microM). Stimulating dependency with reduction fEPSP was seen in the presence of ZNS at clinically relevant concentrations, but not with PrV. The reduction of fEPSP amplitude was not accompanied by a change in paired-pulse facilitation. These data suggest that at clinically relevant concentrations of ZNS, the suppression of neuronal propagation is at least partially due to the postsynaptic mechanism, probably through alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors.
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Affiliation(s)
- Chin-Wei Huang
- Department of Neurology, Institute of Clinical Medicine, National Cheng-Kung University Medical Center, No. 1, University Road, Tainan, Taiwan.
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30
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Large CH, Webster EL, Goff DC. The potential role of lamotrigine in schizophrenia. Psychopharmacology (Berl) 2005; 181:415-36. [PMID: 16001126 DOI: 10.1007/s00213-005-0020-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2004] [Accepted: 03/29/2005] [Indexed: 12/16/2022]
Abstract
RATIONALE Atypical antipsychotic drugs are the drugs of choice for the treatment of schizophrenia. However, despite advances, no treatments have been established for patients who fail to improve with the most effective of these, clozapine. The inhibition of dopamine transmission through blockade of dopamine D2 receptors is considered to be essential for antipsychotic efficacy, but it is postulated that modulation of glutamate transmission may be equally important. In support of this, symptoms similar to schizophrenia can be induced in healthy volunteers using N-methyl-D-aspartate (NMDA) antagonist drugs that are also known to enhance glutamate transmission. Furthermore, lamotrigine, which can modulate glutamate release, may add to or synergise with atypical antipsychotic drugs, some of which may themselves modulate glutamate transmission. OBJECTIVES We examine the evidence for the efficacy of lamotrigine. We consider how this fits with a glutamate neuron dysregulation hypothesis of the disorder. We discuss mechanisms by which lamotrigine might influence neuronal activity and glutamate transmission, and possible ways in which the drug might interact with antipsychotic medications. RESULTS Data from four clinical studies support the efficacy of adjunctive lamotrigine in the treatment of schizophrenia. In addition, and consistent with a glutamate neuron dysregulation hypothesis of schizophrenia, lamotrigine can prevent the psychotic symptoms or behavioural disruption induced by NMDA receptor antagonists in healthy volunteers or rodents. CONCLUSIONS The efficacy of lamotrigine is most likely explained within the framework of a glutamate neuron dysregulation hypothesis, and may arise primarily through the drugs ability to influence glutamate transmission and neural activity in the cortex. The drug is likely to act through inhibition of voltage-gated sodium channels, though other molecular interactions cannot be ruled out. Lamotrigine may add to or synergise with some atypical antipsychotic drugs acting on glutamate transmission; alternatively, they may act independently on glutamate and dopamine systems to bring about a combined therapeutic effect. We propose new strategies for the treatment of schizophrenia using a combination of anti-dopaminergic and anti-glutamatergic drugs.
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Affiliation(s)
- Charles H Large
- Department of Neuropharmacology, Psychiatry CEDD, GlaxoSmithKline SpA, Via Fleming 4, 37135, Verona, Italy.
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Zhu G, Okada M, Uchiyama D, Ohkubo T, Yoshida S, Kaneko S. Hyperactivity of Endoplasmic Reticulum Associated Exocytosis Mechanism Contributes to Acute Phencyclidine Intoxication. J Pharmacol Sci 2004; 95:214-27. [PMID: 15215646 DOI: 10.1254/jphs.fp0040044] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Phencyclidine (PCP) produces schizophrenia-like psychosis and acute PCP-intoxications; however, whether glutamate/NMDA-receptor blockade by PCP modulates or not these mechanisms has remained to be clarified. To clarify this mechanism, we determined interaction among voltage-gated Na(+)-channel inhibitor, tetrodotoxin (TTX), Golgi-disturbing-agent, brefeldin-A (BFA), and PCP on releases of glutamate, GABA, and monoamine in prefrontal-cortex (pFC), using microdialysis. PCP increased basal monoamine release, whereas it decreased basal GABA release, without affecting glutamate release. PCP increased K(+)-evoked monoamine release, whereas it decreased K(+)-evoked glutamate and GABA releases. TTX reduced basal monoamine and GABA releases without affecting glutamate release, whereas BFA did not affect them. Interestingly, BFA and TTX inhibited PCP-associated basal monoamine release and abolished PCP-induced reduction of basal GABA release without affecting glutamate release. BFA and TTX reduced K(+)-evoked releases of all neurotransmitters. BFA inhibited PCP-associated K(+)-evoked monoamine release, but TTX did not affect them. PCP-induced reduction of K(+)-evoked GABA and glutamate releases was abolished by TTX and BFA. These results indicate that PCP reduces GABAergic transmission via NMDA-receptor blockade and activates intracellular endoplasmic-reticulum-associated signal-transduction, resulting in enhancement of monoaminergic transmission in pFC. Thus, these PCP properties support the hypothesis that mechanisms of the neurological symptoms of acute PCP-intoxication, convulsion, and rhabdomyolysis may be involved in both reduction of GABAergic-transmission and activation of endoplasmic-reticulum-associated signal-transduction induced by PCP.
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Affiliation(s)
- Gang Zhu
- Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki, Japan
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Okada M, Zhu G, Yoshida S, Kanai K, Hirose S, Kaneko S. Exocytosis mechanism as a new targeting site for mechanisms of action of antiepileptic drugs. Life Sci 2002; 72:465-73. [PMID: 12467887 DOI: 10.1016/s0024-3205(02)02283-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Carbamazepine (CBZ) and zonisamide (ZNS) are effective antiepileptic drugs (AEDs) for the treatment of epilepsy and mood disorder. One of the mechanisms of action of CBZ and ZNS is inactivation of voltage-gated Na+ channel (VGSC). However, the major mechanism(s) of action of these AEDs is not clear yet. We have been exploring novel targeting mechanisms for the antiepileptic actions of CBZ and ZNS during the past ten years. In this report, we describe our hypothesis regarding the new targeting mechanisms for the antiepileptic action of AEDs. We determined an interaction between these AEDs and inhibitors of both voltage-sensitive Ca2+ channels (VSCCs) and soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) on neurotransmitter exocytosis using microdialysis. Perfusion with therapeutic concentrations of CBZ and ZNS increased basal neurotransmitter release. This stimulatory action was predominantly inhibited by inhibitors of N-type VSCC and syntaxin. CBZ and ZNS increased Ca2+-evoked release, an action selectively inhibited by inhibitors of N-type VSCC and syntaxin. CBZ and ZNS reduced K+-evoked release, an action predominantly inhibited by inhibitors of P-type VSCCs and synaptobrevin. These actions of CBZ and ZNS on neurotransmitter exocytosis could be observed under the condition of inhibition of VGSC using perfusion with tetrodotoxin. Our findings enhance our understanding of the mechanisms of action of CBZ and ZNS as AEDs, which possibly reduce P-type VSCCs/synaptobrevin-related exocytosis mechanisms during the depolarization stage, and simultaneously enhance N-type VSCCs/syntaxin-related exocytosis mechanisms at the resting stage.
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Affiliation(s)
- Motohiro Okada
- Department of Neuropsychiatry, Hirosaki University, 036-8562, Hirosaki, Japan.
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