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Chen D, Liu C, Wang F, Li P, Wei Z, Nie D, Liu P, Liu H. Structure-function interrelationships and associated neurotransmitter profiles in drug-naïve benign childhood epilepsy with central-temporal spikes patients. Eur Radiol 2024:10.1007/s00330-024-10954-7. [PMID: 39009880 DOI: 10.1007/s00330-024-10954-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 05/12/2024] [Accepted: 06/27/2024] [Indexed: 07/17/2024]
Abstract
OBJECTIVES To explore the interrelationships between structural and functional changes as well as the potential neurotransmitter profile alterations in drug-naïve benign childhood epilepsy with central-temporal spikes (BECTS) patients. METHODS Structural magnetic resonance imaging (sMRI) and resting-state functional MRI data from 20 drug-naïve BECTS patients and 33 healthy controls (HCs) were acquired. Parallel independent component analysis (P-ICA) was used to identify covarying components among gray matter volume (GMV) maps and fractional amplitude of low-frequency fluctuations (fALFF) maps. Furthermore, we explored the spatial correlations between GMV/fALFF changes derived from P-ICA and neurotransmitter maps in JuSpace toolbox. RESULTS A significantly positive correlation (p < 0.001) was identified between one structural component (GMV_IC6) and one functional component (fALFF_IC4), which showed significant group differences between drug-naïve BECTS patients and HCs (GMV_IC6: p < 0.01; fALFF_IC4: p < 0.001). GMV_IC6 showed increased GMV in the frontal lobe, temporal lobe, thalamus, and precentral gyrus as well as fALFF_IC4 had enhanced fALFF in the cerebellum in drug-naïve BECTS patients compared to HCs. Moreover, significant correlations between GMV alterations in GMV_IC6 and the serotonin (5HT1a: p < 0.001; 5HT2a: p < 0.001), norepinephrine (NAT: p < 0.001) and glutamate systems (mGluR5: p < 0.001) as well as between fALFF alterations in fALFF_IC4 and the norepinephrine system (NAT: p < 0.001) were detected. CONCLUSION The current findings suggest co-altered structural/functional components that reflect the correlation of language and motor networks as well as associated with the serotonergic, noradrenergic, and glutamatergic neurotransmitter systems. CLINICAL RELEVANCE STATEMENT The relationship between anatomical brain structure and intrinsic neural activity was evaluated using a multimodal fusion analysis and neurotransmitters which might provide an important window into the multimodal neural and underlying molecular mechanisms of benign childhood epilepsy with central-temporal spikes. KEY POINTS Structure-function relationships in drug-naïve benign childhood epilepsy with central-temporal spikes (BECTS) patients were explored. The interrelated structure-function components were found and correlated with the serotonin, norepinephrine, and glutamate systems. Co-altered structural/functional components reflect the correlation of language and motor networks and correlate with the specific neurotransmitter systems.
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Affiliation(s)
- Duoli Chen
- School of Life Science and Technology, Xidian University, Xi'an, China
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi'an, China
| | - Chengxiang Liu
- School of Life Science and Technology, Xidian University, Xi'an, China
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi'an, China
| | - Fuqin Wang
- Department of Radiology, The Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Pengyu Li
- School of Life Science and Technology, Xidian University, Xi'an, China
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi'an, China
| | - Zi Wei
- School of Life Science and Technology, Xidian University, Xi'an, China
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi'an, China
| | - Dingxin Nie
- School of Life Science and Technology, Xidian University, Xi'an, China
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi'an, China
| | - Peng Liu
- School of Life Science and Technology, Xidian University, Xi'an, China.
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi'an, China.
| | - Heng Liu
- Department of Radiology, The Affiliated Hospital of Zunyi Medical University, Zunyi, China.
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Dell'isola GB, Verrotti A, Sciaccaluga M, Roberti R, Parnetti L, Russo E, Costa C. Evaluating bexicaserin for the treatment of developmental epileptic encephalopathies. Expert Opin Pharmacother 2024; 25:1121-1130. [PMID: 38916481 DOI: 10.1080/14656566.2024.2373350] [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] [Received: 05/13/2024] [Accepted: 06/24/2024] [Indexed: 06/26/2024]
Abstract
INTRODUCTION Developmental epileptic encephalopathies (DEEs) pose significant challenges due to their refractory nature and limited treatment options. Despite advancements in genetic understanding, effective therapies targeting underlying pathophysiology are lacking. Serotoninergic dysfunction has been implicated in epilepsy, sparking interest in serotonin as a therapeutic target. AREA COVERED This article explores the potential of bexicaserin, a selective 5-HT2C receptor agonist, as an adjunctive antiseizure medication in DEEs. Bexicaserin is thought to modulate GABAergic neurotransmission, suppressing central hyperexcitability. Preclinical studies demonstrate its efficacy across various seizure models. Clinical trials, including the Pacific Study, reveal promising results in reducing motor seizures. However, challenges such as adverse effects and treatment discontinuation underscore the need for further investigation. EXPERT OPINION The efficacy of 5-HT2C serotoninergic agonists, validated in preclinical and clinical studies, highlights serotonin's role in DEEs. Bexicaserin offers new therapeutic possibilities, potentially synergizing with existing antiseizure medications. Polypharmacotherapy, targeting distinct pathways, may enhance therapeutic outcomes. Monitoring pharmacological interactions and addressing central nervous system comorbidities are crucial for optimizing treatment strategies. Further research is needed to elucidate bexicaserin's mechanisms and potential antiepileptogenic effects.
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Affiliation(s)
| | | | - Miriam Sciaccaluga
- Section of Neurology, Laboratory of Experimental Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
- Mauro Baschirotto Rare Disease Foundation BIRD Onlus, Longare, VI, Italy
| | - Roberta Roberti
- Science of Health Department, University Magna Grecia of Catanzaro, Catanzaro, Italy
| | - Lucilla Parnetti
- Section of Neurology, Laboratory of Experimental Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Emilio Russo
- Science of Health Department, University Magna Grecia of Catanzaro, Catanzaro, Italy
| | - Cinzia Costa
- Section of Neurology, Laboratory of Experimental Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
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Tyagi R, Saraf TS, Canal CE. The Psychedelic N, N-Dipropyltryptamine Prevents Seizures in a Mouse Model of Fragile X Syndrome via a Mechanism that Appears Independent of Serotonin and Sigma1 Receptors. ACS Pharmacol Transl Sci 2023; 6:1480-1491. [PMID: 37854624 PMCID: PMC10580393 DOI: 10.1021/acsptsci.3c00137] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Indexed: 10/20/2023]
Abstract
The serotonergic psychedelic psilocybin shows efficacy in treating neuropsychiatric disorders, though the mechanism(s) underlying its therapeutic effects remain unclear. We show that a similar psychedelic tryptamine, N,N-dipropyltryptamine (DPT), completely prevents audiogenic seizures (AGS) in an Fmr1 knockout mouse model of fragile X syndrome at a 10 mg/kg dose but not at lower doses (3 or 5.6 mg/kg). Despite showing in vitro that DPT is a serotonin 5-HT2A, 5-HT1B, and 5-HT1A receptor agonist (with that rank order of functional potency, determined with TRUPATH Gα/βγ biosensors), pretreatment with selective inhibitors of 5-HT2A/2C, 5-HT1B, or 5-HT1A receptors did not block DPT's antiepileptic effects; a pan-serotonin receptor antagonist was also ineffective. Because 5-HT1A receptor activation blocks AGS in Fmr1 knockout mice, we performed a dose-response experiment to evaluate DPT's engagement of 5-HT1A receptors in vivo. DPT elicited 5-HT1A-dependent effects only at doses greater than 10 mg/kg, further supporting that DPT's antiepileptic effects were not 5-HT1A-mediated. We also observed that the selective sigma1 receptor antagonist, NE-100, did not impact DPT's antiepileptic effects, suggesting DPT engagement of sigma1 receptors was not a crucial mechanism. Separately, we observed that DPT and NE-100 at high doses caused convulsions on their own that were qualitatively distinct from AGS. In conclusion, DPT dose-dependently blocked AGS in Fmr1 knockout mice, but neither serotonin nor sigma1 receptor antagonists prevented this action. Thus, DPT might have neurotherapeutic effects independent of its serotonergic psychedelic properties. However, DPT also caused seizures at high doses, showing that DPT has complex dose-dependent in vivo polypharmacology.
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Affiliation(s)
- Richa Tyagi
- Department of Pharmaceutical
Sciences, College of Pharmacy, Mercer University, 3001 Mercer University Drive, Atlanta, Georgia 30341, United States
| | - Tanishka S. Saraf
- Department of Pharmaceutical
Sciences, College of Pharmacy, Mercer University, 3001 Mercer University Drive, Atlanta, Georgia 30341, United States
| | - Clinton E. Canal
- Department of Pharmaceutical
Sciences, College of Pharmacy, Mercer University, 3001 Mercer University Drive, Atlanta, Georgia 30341, United States
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Chauhan A, Singh J, Sangwan N, Singh H, Prakash A, Medhi B, Avti PK. Designing the 5HT 2BR structure and its modulation as a therapeutic target for repurposing approach in drug-resistant epilepsy. Epilepsy Res 2023; 194:107168. [PMID: 37302343 DOI: 10.1016/j.eplepsyres.2023.107168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/24/2023] [Accepted: 05/22/2023] [Indexed: 06/13/2023]
Abstract
The study intends to repurpose FDA drugs and investigate the mechanism of (5HT2BR) activation by comprehending inter-residue interactions. The 5HT2BR is a novel thread, and its role in reducing seizures in Dravet syndrome is emerging. The crystal structure (5HT2BR) is a chimera with mutations; hence 3D-structure is modeled (4IB4: 5HT2BRM). The structure is cross-validated to simulate the human receptor using enrichment analysis (ROC: 0.79) and SAVESv6.0. Virtual screening of 2456 approved drugs yielded the best hits that are subjected to MM/GBSA and molecular dynamic (MD) simulations. The 2 top drugs Cabergoline (-53.44 kcal/mol) and Methylergonovine (-40.42 kcal/mol), display strong binding affinity, and ADMET/SAR analysis also suggests their non-mutagenic or non-carcinogenic nature. Methylergonovine has a weaker binding affinity and lower potency than standards [Ergotamine (agonist) and Methysergide (antagonist)] due to its higher Ki (1.32 M) and Kd (6.44 ×10-8 M) values. Compared to standards, Cabergoline has moderate binding affinity and potency [Ki = 0.85 M and Kd = 5.53 × 10-8 M]. The top 2 drugs primarily interact with conserved residues (ASP135, LEU209, GLY221, ALA225, and THR140) as in agonists, unlike the antagonist. The top 2 drugs, upon binding to the 5HT2BRM, modify the helices VI, V, and III and shift the RMSD 2.48 Å and 3.07 Å. LEU209 forms a latch with residues 207-214 (forms a lid) in the 5HT2BRM receptor, which enhances agonist binding and prevents drug escape. Methylergonovine and Cabergoline interact more stongly with ALA225 than the antagonist. The post-MD analysis of Cabergoline suggests a better MM/GBSA value (-89.21 kcal/mol) than Methylergonovine (-63.54 kcal/mol). In this study, Cabergoline and Methylergonovine's agonistic mechanism and solid binding properties suggest their strong role in regulating the 5HT2BR and might target drug-resistant epilepsy.
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Affiliation(s)
| | | | | | | | - Ajay Prakash
- Department of Pharmacology, PGIMER, Chandigarh, India
| | - Bikash Medhi
- Department of Pharmacology, PGIMER, Chandigarh, India
| | - Pramod K Avti
- Department of Biophysics, PGIMER, Chandigarh, India.
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Chauhan A, Sangwan N, Singh J, Prakash A, Medhi B, Avti PK. Allosteric modulation of conserved motifs and helices in 5HT 2BR: Advances drug discovery and therapeutic approach towards drug resistant epilepsy. J Biomol Struct Dyn 2023; 41:13113-13126. [PMID: 36809314 DOI: 10.1080/07391102.2023.2178508] [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] [Received: 11/03/2022] [Accepted: 01/13/2023] [Indexed: 02/23/2023]
Abstract
The 5HT2BR, class-A GPCR is a new target, and its significance for seizure reduction in Dravet syndrome is just now gaining interest, suggesting its specific role in epileptic seizure management. Homology modeling of human 5HT2BR (P41595), was performed using a template 4IB4, the modeled structure was cross-validated (stereo chemical hindrance, Ramachandran plot, enrichment analysis) to mimic a closer native structure. Virtual screening (8532 compounds), drug-likeliness, mutagenicity, and carcinogenicity profiling prioritized six compounds for molecular dynamics (500 ns), Rgyr, DCCM. The receptor's C-alpha fluctuation upon bound agonist (6.91 Å), known antagonist (7.03 Å), and LAS 52115629 (5.83 Å) binding varies, leading to receptor stabilization. The residues C-alpha side-chain in active site strongly interacts (hydrogen bonds) with bound agonist (100% interaction: ASP135), known antagonist (95%:ASP135), and LAS 52115629 (100%:ASP135). The Rgyr for receptor-ligand complex, LAS 52115629 (25.68 Å), lies close to bound agonist-Ergotamine, and DCCM analysis also shows strong positive correlations for LAS 52115629 as compared to known drugs. LAS 52115629 is less likely to cause toxicity than known drugs. The structural parameters in the modeled receptor's conserved motifs (DRY, PIF, NPY) were altered for receptor activation upon ligand-binding, which otherwise was in the in-activated state. The ligand (LAS 52115629)-binding further alters the helices-III, V, VI (G-protein bound), and VII, which form potential interacting sites with the receptor and are proven necessary for activating the receptor. Therefore, LAS 52115629 can act as a potential 5HT2BR agonist, targeting drug-resistant epilepsy.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Arushi Chauhan
- Department of Biophysics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Namrata Sangwan
- Department of Biophysics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Jitender Singh
- Department of Biophysics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Ajay Prakash
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Bikash Medhi
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Pramod K Avti
- Department of Biophysics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Deidda G, Crunelli V, Di Giovanni G. 5-HT/GABA interaction in epilepsy. PROGRESS IN BRAIN RESEARCH 2021; 259:265-286. [PMID: 33541679 DOI: 10.1016/bs.pbr.2021.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Epilepsy is a neurological condition characterized by synchronous neuronal oscillations (seizures) in the electroencephalogram. Seizures are classified in focal or generalized (depending on the brain territory interested during seizures), and in convulsive and/or not convulsive (depending on the presence or not of involuntary movements). The current pharmacological treatments are mainly based on GABA modulation although different neurotransmitters are also involved in epilepsy, including serotonin. However despite much extensive progress in the understanding of epilepsy mechanisms, still, a percentage of people with epilepsy are pharmaco-resistant calling for the need for new therapeutic targets. Here we review preclinical and human evidence showing that serotonin modulates epilepsy that this likely happens via a major modulation/interaction with GABA.
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Affiliation(s)
- Gabriele Deidda
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.
| | - Vincenzo Crunelli
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
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Mosińska P, Socała K, Nieoczym D, Laudon M, Storr M, Fichna J, Wlaź P. Anticonvulsant activity of melatonin, but not melatonin receptor agonists Neu-P11 and Neu-P67, in mice. Behav Brain Res 2016; 307:199-207. [DOI: 10.1016/j.bbr.2016.03.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/03/2016] [Accepted: 03/21/2016] [Indexed: 11/26/2022]
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Serotonin receptor antagonists increase fast ripple activity in rats treated with kainic acid. Brain Res Bull 2016; 121:59-67. [DOI: 10.1016/j.brainresbull.2016.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Revised: 11/30/2015] [Accepted: 01/04/2016] [Indexed: 11/22/2022]
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Guiard BP, Di Giovanni G. Central serotonin-2A (5-HT2A) receptor dysfunction in depression and epilepsy: the missing link? Front Pharmacol 2015; 6:46. [PMID: 25852551 PMCID: PMC4362472 DOI: 10.3389/fphar.2015.00046] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 02/24/2015] [Indexed: 11/17/2022] Open
Abstract
5-Hydroxytryptamine 2A receptors (5-HT2A-Rs) are G-protein coupled receptors. In agreement with their location in the brain, they have been implicated not only in various central physiological functions including memory, sleep, nociception, eating and reward behaviors, but also in many neuropsychiatric disorders. Interestingly, a bidirectional link between depression and epilepsy is suspected since patients with depression and especially suicide attempters have an increased seizure risk, while a significant percentage of epileptic patients suffer from depression. Such epidemiological data led us to hypothesize that both pathologies may share common anatomical and neurobiological alteration of the 5-HT2A signaling. After a brief presentation of the pharmacological properties of the 5-HT2A-Rs, this review illustrates how these receptors may directly or indirectly control neuronal excitability in most networks involved in depression and epilepsy through interactions with the monoaminergic, GABAergic and glutamatergic neurotransmissions. It also synthetizes the preclinical and clinical evidence demonstrating the role of these receptors in antidepressant and antiepileptic responses.
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Affiliation(s)
- Bruno P Guiard
- CNRS, Centre de Recherches sur la Cognition Animale, UMR 5169, Toulouse France ; CNRS, Centre de Recherches sur la Cognition Animale Université de Toulouse 3, UMR 5169, Toulouse, France ; INSERM U1178 Team ≪Depression and Antidepressants≫ Faculté de Pharmacie Paris Sud, Châtenay-Malabry, France
| | - Giuseppe Di Giovanni
- Neurophysiology Unit, Laboratory for the Study of Neurological Disorders, Department of Physiology and Biochemistry, University of Malta, Msida Malta ; School of Biosciences, University of Cardiff, Cardiff UK
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Markgraf CG, DeBoer E, Zhai J, Cornelius L, Zhou YY, MacSweeney C. Assessment of seizure liability of Org 306039, a 5-HT2c agonist, using hippocampal brain slice and rodent EEG telemetry. J Pharmacol Toxicol Methods 2014; 70:224-9. [DOI: 10.1016/j.vascn.2014.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 08/07/2014] [Accepted: 08/08/2014] [Indexed: 11/25/2022]
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Sapa J, Zygmunt M, Kulig K, Malawska B, Dudek M, Filipek B, Bednarski M, Kusak A, Nowak G. Evaluation of anticonvulsant activity of novel pyrrolidin-2-one derivatives. Pharmacol Rep 2014; 66:708-11. [DOI: 10.1016/j.pharep.2014.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 02/11/2014] [Accepted: 02/14/2014] [Indexed: 11/25/2022]
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Gunkara OT, Sucu BO, Guleli M, Ocal N. Synthesis of New Tandospirone Analogues Carrying 1-(3-(Trifluoromethyl)phenyl)piperazine. SYNTHETIC COMMUN 2014. [DOI: 10.1080/00397911.2013.865236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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The role of different serotonin receptor subtypes in seizure susceptibility. Exp Brain Res 2013; 232:347-67. [PMID: 24232860 DOI: 10.1007/s00221-013-3757-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Accepted: 10/27/2013] [Indexed: 10/26/2022]
Abstract
5-Hydroxytryptamine (5-HT) has the most diverse set of receptors in comparison with any other neurotransmitter or hormone in the body. To date, seven families of 5-HT receptors have been characterized. A great number of studies have been published regarding the role of 5-HT and its receptors in seizures. However, with a few exceptions, the net effect of activating or inhibiting each 5-HT receptor subtype on the development or severity of seizures remains controversial. Additionally, the results of studies, which have used knockout animals to investigate the role of 5-HT receptors in seizures, have sometimes been contradictory to those which have used pharmacological tools. The present study aims to review the available data regarding the influence of each receptor subtype on seizure development and, when possible, reconcile between the apparently different results obtained in these studies.
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Design, synthesis, and anticonvulsant screening of some substituted piperazine and aniline derivatives of 5-phenyl-oxazolidin-2,4-diones and 5,5-diphenylimidazolidin-2,4 diones. Med Chem Res 2011. [DOI: 10.1007/s00044-011-9805-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Dhanawat M, Das N, Shrivastava SK. Design, synthesis, anticonvulsant screening and 5HT 1A/2A receptor affinity of N(3)-substituted 2,4-imidazolidinediones and oxazolidinediones. Drug Discov Ther 2011; 5:227-37. [DOI: 10.5582/ddt.2011.v5.5.227] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Meenakshi Dhanawat
- Department of Pharmaceutics, Institute of Technology, Banaras Hindu University
| | - Nirupam Das
- Department of Pharmaceutics, Institute of Technology, Banaras Hindu University
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Abstract
In recent years, there has been increasing evidence that serotonergic neurotransmission modulates a wide variety of experimentally induced seizures. Generally, agents that elevate extracellular serotonin (5-HT) levels, such as 5-hydroxytryptophan and serotonin reuptake blockers, inhibit both focal and generalized seizures, although exceptions have been described, too. Conversely, depletion of brain 5-HT lowers the threshold to audiogenically, chemically and electrically evoked convulsions. Furthermore, it has been shown that several anti-epileptic drugs increase endogenous extracellular 5-HT concentration. 5-HT receptors are expressed in almost all networks involved in epilepsies. Currently, the role of at least 5-HT(1A), 5-HT(2C), 5-HT(3) and 5-HT(7) receptor subtypes in epileptogenesis and/or propagation has been described. Mutant mice lacking 5-HT(1A) or 5-HT(2C) receptors show increased seizure activity and/or lower threshold. In general, hyperpolarization of glutamatergic neurons by 5-HT(1A) receptors and depolarization of GABAergic neurons by 5-HT(2C) receptors as well as antagonists of 5-HT(3) and 5-HT(7) receptors decrease the excitability in most, but not all, networks involved in epilepsies. Imaging data and analysis of resected tissue of epileptic patients, and studies in animal models all provide evidence that endogenous 5-HT, the activity of its receptors, and pharmaceuticals with serotonin agonist and/or antagonist properties play a significant role in the pathogenesis of epilepsies.
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Affiliation(s)
- Gyorgy Bagdy
- Laboratory of Neurochemistry and Experimental Medicine, National Institute of Psychiatry and Neurology, Budapest, Hungary.
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Wesołowska A, Nikiforuk A, Chojnacka-Wójcik E. Anticonvulsant effect of the selective 5-HT1B receptor agonist CP 94253 in mice. Eur J Pharmacol 2006; 541:57-63. [PMID: 16765343 DOI: 10.1016/j.ejphar.2006.04.049] [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: 02/13/2006] [Revised: 04/27/2006] [Accepted: 04/28/2006] [Indexed: 11/25/2022]
Abstract
The effect of the selective 5-hydroxytryptamine1B (5-HT1B) receptor agonist 5-propoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-pyrrolo[3,2-b]pyridine (CP 94253) and the 5-HT1A/1B/1D receptor agonist 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridyl)-1H-indole (RU 24969) in maximal electroshock- and pentylenetetrazol-induced seizures in mice was examined. CP 94253 (10-40 mg/kg) afforded no protection against maximal electroshock-evoked convulsions, but produced anticonvulsant action in the pentylenetetrazol-induced seizures (ED50 = 29 mg/kg). The anticonvulsant effect of CP 94253 was abolished by the selective 5-HT1B receptor antagonist N-[3-(2-dimethylamino)ethoxy-4-methoxyphenyl]-2'-methyl-4'-(5-methyl-1,2,4-oxadiazol-3-yl)-(1,1'-biphenyl)-4-carboxamide (SB 216641; 20 mg/kg) but it was maintained following the p-chlorophenylalanine (p-CPA; 3 x 300 mg/kg)-induced 5-HT depletion. Interestingly, CP 94253 potentiated the anticonvulsant activity of diazepam in the pentylenetetrazol test; on the other hand, the benzodiazepine receptor antagonist, flumazenil (10 mg/kg), did not modify the anticonvulsant effect of CP 94253. RU 24969 (5 mg/kg) evoked no effect in the maximal electroshock model, but it produced anticonvulsant activity in the pentylenetetrazol assay, the latter effect being attenuated by the selective 5-HT1A receptor antagonist N-(2-[4-(2-methoxyphenyl)piperazin-1-yl]ethyl)-N-(2-pyridyl)-cyclohexanecarboxamide (WAY 100635; 0.3 mg/kg) and SB 216641 (10-20 mg/kg). The obtained results suggest that CP 94253 exerts anticonvulsant activity on pentylenetetrazol-induced seizures in mice, as a consequence of stimulation of 5-HT1B receptors (probably located postsynaptically and/or as heteroreceptors); the antiseizure activity of RU 24969 seems to depend on the stimulation of both 5-HT1A and 5-HT1B receptors.
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Affiliation(s)
- Anna Wesołowska
- Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, Kraków, PL 31-343, Poland
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Obniska J, Kołaczkowski M, Bojarski AJ, Duszyńska B. Synthesis, anticonvulsant activity and 5-HT1A, 5-HT2A receptor affinity of new N-[(4-arylpiperazin-1-yl)-alkyl] derivatives of 2-azaspiro[4.4]nonane and [4.5]decane-1,3-dione. Eur J Med Chem 2006; 41:874-81. [PMID: 16600439 DOI: 10.1016/j.ejmech.2006.03.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 03/03/2006] [Accepted: 03/06/2006] [Indexed: 11/17/2022]
Abstract
The synthesis, physicochemical and pharmacological properties of new N-[(4-arylpiperazin-1-yl)-alkyl]-2-azaspiro[4.4]nonane- (8a-c, 10a-d) and [4.5]decane-1,3-dione (9a-c, 11a-d) derivatives were described. The antiepileptic effects of those compounds were examined by a maximal electroshock (MES) and a pentylenetetrazole (sc. PTZ) tests, and their neurotoxicity was determined using a rota-rod test. Compounds 8c, 9c, 10c, d, 11c, d with a CF(3) group at the 3-position of the 4-arylpiperazine fragment exhibited anti-seizure properties in the MES model; in contrast, their 2-CH(3) and 2-OCH(3) analogues were inactive in both the tests used. Moreover, since the investigated compounds belong to the class of long-chain arylpiperazines, their serotonin 5-HT(1A) and 5-HT(2A) receptor affinity was determined. The relationship between the length of alkylene spacer and 5-HT(1A)/5-HT(2A) receptor activity was observed. Compounds with an ethylene and a propylene bridge (10a-d and 11a-d) were 3-80-fold more potent (K(i) ranged from 3.1 to 94 nM for 5-HT(1A) and 32-465 nM for 5-HT(2A)) than their methylene analogues (8a-c and 9a-c; K(i) ranged from 81 to 370 nM for 5-HT(1A) and 126-1370 nM for 5-HT(2A)). The highest 5-HT(1A) receptor affinity was displayed by 2-OCH(3) and 3-CF(3) phenyl derivatives (10b, 11b: K(i)=6.8 and 5.7 nM, respectively, and 10c, 11c: K(i)=6.0 and 3.1 nM, respectively), while in the case of 5-HT(2A) receptor the highest affinity was observed for the 3-CF(3) phenyl derivatives 10c, d, 11c, d (K(i) ranged from 32 to 86 nM).
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Affiliation(s)
- J Obniska
- Department of Pharmaceutical Chemistry, Jagiellonian University Medical College, Kraków, Poland.
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Stean TO, Atkins AR, Heidbreder CA, Quinn LP, Trail BK, Upton N. Postsynaptic 5-HT1B receptors modulate electroshock-induced generalised seizures in rats. Br J Pharmacol 2005; 144:628-35. [PMID: 15678098 PMCID: PMC1576040 DOI: 10.1038/sj.bjp.0706027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. Although an important regulatory role for serotonin (5-HT) in seizure activation and propagation is well established, relatively little is known of the function of specific 5-HT receptor subtypes on seizure modulation. 2. The aim of the present study was to investigate the role of 5-HT(1A, 1B and 1D) receptors in modulating generalised seizures in the rat maximal electroshock seizure threshold (MEST) test. 3. The mixed 5-HT receptor agonists SKF 99101 (5-20 mg kg(-1) i.p.) and RU 24969 (1-5 mg kg(-1) i.p.), 0.5 h pretest, both produced marked dose-related increases in seizure threshold. These agents share high affinity for 5-HT(1A, 1B and 1D) receptors. 4. Antiseizure effects induced by submaximal doses of these agonists were maintained following p-chlorophenylalanine (150 mg kg(-1) i.p. x 3 days)-induced 5-HT depletion. 5. The anticonvulsant action of both SKF 99101 (15 mg kg(-1) i.p.) and RU 24969 (2.5 mg kg(-1) i.p.) was dose-dependently abolished by the selective 5-HT1B receptor antagonist SB-224289 (0.1-3 mg kg(-1) p.o., 3 h pretest) but was unaffected by the selective 5-HT1A receptor antagonist WAY 100635 (0.01-0.3 mg kg(-1) s.c., 1 h pretest). This indicates that 5-HT1B receptors are primarily involved in mediating the anticonvulsant properties of these agents. 6. In addition, the ability of the 5-HT(1B/1D) receptor antagonist GR 127935 (0.3-3 mg kg(-1) s.c., 60 min pretest) to dose-dependently inhibit SKF 99101-induced elevation of seizure threshold also suggests possible downstream involvement of 5-HT1D receptors in the action of this agonist, although confirmation awaits the identification of a selective 5-HT1D receptor antagonist. 7. Overall, these data demonstrate that stimulation of postsynaptic 5-HT1B receptors inhibits electroshock-induced seizure spread in rats.
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Affiliation(s)
- Tania O Stean
- Neurology & GI-CEDD, GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW.
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21
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Jakus R, Graf M, Juhasz G, Gerber K, Levay G, Halasz P, Bagdy G. 5-HT2C receptors inhibit and 5-HT1A receptors activate the generation of spike–wave discharges in a genetic rat model of absence epilepsy. Exp Neurol 2003; 184:964-72. [PMID: 14769389 DOI: 10.1016/s0014-4886(03)00352-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2003] [Revised: 07/10/2003] [Accepted: 07/11/2003] [Indexed: 11/21/2022]
Abstract
The present study was conducted to investigate the role of 5-HT(2C) and 5-HT(1A) receptors in the generation of spike-wave discharges (SWD) in the genetic absence epilepsy model Wistar Albino Glaxo rats from Rijswijk, Netherlands (WAG/Rij rats). We have determined the effects of the 5-HT(2C) receptor preferring agonist m-chlorophenyl-piperazine (m-CPP), the selective 5-HT(2C) receptor antagonist SB-242084, the selective 5-HT(1A) receptor antagonist WAY-100635, two selective serotonin re-uptake inhibitors (SSRI, fluoxetine and citalopram) and their combinations in this model. The 5-HT(2C) agonist m-CPP caused marked, dose-dependent decreases in the cumulative duration and number of SWD administered either intraperitoneally (0.9 and 2.5 mg/kg) or intracerebroventricularly (0.05 and 0.1 mg/kg). Treatment with SB-242084 (0.2 mg/kg, ip) alone failed to cause any significant change in SWD compared to vehicle. Pretreatment with SB-242084 (0.2 mg/kg, ip) eliminated the effects of m-CPP on SWD. Fluoxetine (5.0 mg/kg, ip) alone caused moderate increase in SWD. After pretreatment with SB-242084, the effect of fluoxetine was significantly enhanced. The combination of SB-242084 and citalopram (2.5 mg/kg, ip) caused a similar effect, namely an increase in SWD. In contrast, pretreatment with WAY-100635 significantly attenuated the effect of fluoxetine. In conclusion, these results indicate that the increase in endogenous 5-HT produces a dual effect on SWD; the inhibition of epileptiform activity is mediated by 5-HT(2C), the activation by 5-HT(1A) receptors.
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MESH Headings
- Action Potentials/drug effects
- Action Potentials/physiology
- Aminopyridines/pharmacology
- Animals
- Citalopram/pharmacology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Electroencephalography
- Electromyography
- Epilepsy, Absence/physiopathology
- Fluoxetine/pharmacology
- Indoles/pharmacology
- Injections, Intraperitoneal
- Injections, Intraventricular
- Male
- Piperazines/administration & dosage
- Piperazines/pharmacology
- Pyridines/pharmacology
- Rats
- Rats, Wistar
- Receptor, Serotonin, 5-HT1A/metabolism
- Receptor, Serotonin, 5-HT2C/metabolism
- Serotonin Antagonists/pharmacology
- Serotonin Receptor Agonists/administration & dosage
- Serotonin Receptor Agonists/pharmacology
- Selective Serotonin Reuptake Inhibitors/pharmacology
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Affiliation(s)
- Rita Jakus
- Laboratory of Neurochemistry and Experimental Medicine, Department of Vascular Neurology, Semmelweis University, Budapest, Hungary
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Applegate CD, Tecott LH. Global increases in seizure susceptibility in mice lacking 5-HT2C receptors: a behavioral analysis. Exp Neurol 1998; 154:522-30. [PMID: 9878187 DOI: 10.1006/exnr.1998.6901] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies have shown that mice bearing a targeted disruption of the 5-HT2C receptor gene exhibit an epilepsy syndrome associated with sporadic spontaneous seizures that occasionally result in death. In this study, we have defined the seizure susceptibility profiles of these 5-HT2C receptor mutant mice backcrossed onto a C57BL/6 background. Wild-type and mutant animals were either electrically kindled from the olfactory bulb, exposed to corneal electroshock, or tested with the chemoconvulsant, flurothyl. In all paradigms, mice lacking the 5-HT2C receptor were significantly more seizure susceptible than wild-type controls. Results indicate that mutants have lower focal seizure thresholds, increased focal seizure excitability, and facilitated propagation within the forebrain seizure system. Mutants also exhibit lower generalized seizure thresholds for the expression of both generalized clonic and generalized tonic seizures. Importantly, the 5-HT receptor antagonist, mesulergine (2 or 4 mg/kg), administered prior to electroshock testing, recapitulated the mutant phenotype in wild-type mice. Together, these data strongly implicate a role for serotonin and 5-HT2C receptors in the modulation of neuronal network excitability and seizure propagation globally, throughout the CNS.
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MESH Headings
- Animals
- Behavior, Animal/physiology
- Brain Chemistry/drug effects
- Brain Chemistry/physiology
- Convulsants/pharmacology
- Cornea
- Disease Susceptibility
- Dopamine Agonists/pharmacology
- Electroshock
- Epilepsies, Myoclonic/chemically induced
- Epilepsies, Myoclonic/genetics
- Epilepsy/chemically induced
- Epilepsy/genetics
- Ergolines/pharmacology
- Flurothyl/pharmacology
- Kindling, Neurologic/drug effects
- Kindling, Neurologic/genetics
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Mice, Knockout
- Receptor, Serotonin, 5-HT2C
- Receptors, Serotonin/genetics
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Affiliation(s)
- C D Applegate
- Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, New York, 14642, USA.
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Upton N, Stean T, Middlemiss D, Blackburn T, Kennett G. Studies on the role of 5-HT2C and 5-HT2B receptors in regulating generalised seizure threshold in rodents. Eur J Pharmacol 1998; 359:33-40. [PMID: 9831290 DOI: 10.1016/s0014-2999(98)00621-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The present studies were conducted to investigate the role of 5-HT2C and 5-HT2B receptors in the generation of pentylenetetrazol and electroshock-evoked seizures. The 5-HT2C/2B receptor-preferring agonist 1-(m-chlorophenyl)-piperazine (mCPP; 2.5-7 mg/kg i.p.) weakly elevated seizure threshold in the mouse (but not the rat) electroshock test and also provided appreciable protection against pentylenetetrazol-induced myoclonic and/or tonic seizures in mice and rats, an action that was inhibited by the 5-HT2C/2B receptor antagonist 5-methyl-1-(3-pyridylcarbomoyl)-1,2,3,5-tetrahydropyrrolo[2, 3-f]indole (SB-206553; 10-20 mg/kg p.o.). In contrast, the 5-HT2B receptor agonist 1-[5-(2-thienylmethoxy)-1H-3-indoyl]propan-2-amine hydrochloride (BW-723C86; 3-30 mg/kg s.c.) had no effect on the threshold for generalised seizures in any of the models employed. These results indicate that the observed anticonvulsant effects of mCPP are likely to be mediated by activation of 5-HT2C receptors. However, blockade of these receptors in mice (or rats) by SB-206553 (5-20 mg/kg p.o.) did not result in the reduced seizure threshold characteristic of mutant mice deficient of 5-HT2C receptors, suggesting that in normal adult animals this receptor subtype may usually be subjected to only a low level of 5-hydroxytryptamine tone.
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Affiliation(s)
- N Upton
- Neurosciences Department, SmithKline Beecham Pharmaceuticals, New Frontiers Science Park, Harlow, Essex, UK
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