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Sánchez JD, Gómez-Carpintero J, González JF, Menéndez JC. Twenty-first century antiepileptic drugs. An overview of their targets and synthetic approaches. Eur J Med Chem 2024; 272:116476. [PMID: 38759456 DOI: 10.1016/j.ejmech.2024.116476] [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: 02/21/2024] [Revised: 05/01/2024] [Accepted: 05/02/2024] [Indexed: 05/19/2024]
Abstract
The therapeutic use of the traditional drugs against epilepsy has been hindered by their toxicity and low selectivity. These limitations have stimulated the design and development of new generations of antiepileptic drugs. This review explores the molecular targets and synthesis of the antiepileptic drugs that have entered the market in the 21st century, with a focus on manufacturer synthesis.
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Affiliation(s)
- J Domingo Sánchez
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain
| | - Jorge Gómez-Carpintero
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain
| | - Juan F González
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain
| | - J Carlos Menéndez
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain.
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2
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Lai H, Gao M, Yang H. The potassium channels: Neurobiology and pharmacology of tinnitus. J Neurosci Res 2024; 102:e25281. [PMID: 38284861 DOI: 10.1002/jnr.25281] [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: 04/23/2023] [Revised: 10/27/2023] [Accepted: 11/16/2023] [Indexed: 01/30/2024]
Abstract
Tinnitus is a widespread public health issue that imposes a significant social burden. The occurrence and maintenance of tinnitus have been shown to be associated with abnormal neuronal activity in the auditory pathway. Based on this view, neurobiological and pharmacological developments in tinnitus focus on ion channels and synaptic neurotransmitter receptors in neurons in the auditory pathway. With major breakthroughs in the pathophysiology and research methodology of tinnitus in recent years, the role of the largest family of ion channels, potassium ion channels, in modulating the excitability of neurons involved in tinnitus has been increasingly demonstrated. More and more potassium channels involved in the neural mechanism of tinnitus have been discovered, and corresponding drugs have been developed. In this article, we review animal (mouse, rat, hamster, and guinea-pig), human, and genetic studies on the different potassium channels involved in tinnitus, analyze the limitations of current clinical research on potassium channels, and propose future prospects. The aim of this review is to promote the understanding of the role of potassium ion channels in tinnitus and to advance the development of drugs targeting potassium ion channels for tinnitus.
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Affiliation(s)
- Haohong Lai
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Minqian Gao
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Hearing and Speech-Language Science, Guangzhou Xinhua University, Guangzhou, China
| | - Haidi Yang
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Hearing and Speech-Language Science, Guangzhou Xinhua University, Guangzhou, China
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3
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Henton A, Zhao Y, Tzounopoulos T. A Role for KCNQ Channels on Cell Type-Specific Plasticity in Mouse Auditory Cortex after Peripheral Damage. J Neurosci 2023; 43:2277-2290. [PMID: 36813573 PMCID: PMC10072297 DOI: 10.1523/jneurosci.1070-22.2023] [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: 06/03/2022] [Revised: 02/13/2023] [Accepted: 02/15/2023] [Indexed: 02/24/2023] Open
Abstract
Damage to sensory organs triggers compensatory plasticity mechanisms in sensory cortices. These plasticity mechanisms result in restored cortical responses, despite reduced peripheral input, and contribute to the remarkable recovery of perceptual detection thresholds to sensory stimuli. Overall, peripheral damage is associated with a reduction of cortical GABAergic inhibition; however, less is known about changes in intrinsic properties and the underlying biophysical mechanisms. To study these mechanisms, we used a model of noise-induced peripheral damage in male and female mice. We uncovered a rapid, cell type-specific reduction in the intrinsic excitability of parvalbumin-expressing neurons (PVs) in layer (L) 2/3 of auditory cortex. No changes in the intrinsic excitability of either L2/3 somatostatin-expressing or L2/3 principal neurons (PNs) were observed. The decrease in L2/3 PV excitability was observed 1, but not 7, d after noise exposure, and was evidenced by a hyperpolarization of the resting membrane potential, depolarization of the action potential threshold, and reduction in firing frequency in response to depolarizing current. To uncover the underlying biophysical mechanisms, we recorded potassium currents. We found an increase in KCNQ potassium channel activity in L2/3 PVs of auditory cortex 1 d after noise exposure, associated with a hyperpolarizing shift in the minimal voltage activation of KCNQ channels. This increase contributes to the decreased intrinsic excitability of PVs. Our results highlight cell-type- and channel-specific mechanisms of plasticity after noise-induced hearing loss and will aid in understanding the pathologic processes involved in hearing loss and hearing loss-related disorders, such as tinnitus and hyperacusis.SIGNIFICANCE STATEMENT Noise-induced damage to the peripheral auditory system triggers central plasticity that compensates for the reduced peripheral input. The mechanisms of this plasticity are not fully understood. In the auditory cortex, this plasticity likely contributes to the recovery of sound-evoked responses and perceptual hearing thresholds. Importantly, other functional aspects of hearing do not recover, and peripheral damage may also lead to maladaptive plasticity-related disorders, such as tinnitus and hyperacusis. Here, after noise-induced peripheral damage, we highlight a rapid, transient, and cell type-specific reduction in the excitability of layer 2/3 parvalbumin-expressing neurons, which is due, at least in part, to increased KCNQ potassium channel activity. These studies may highlight novel strategies for enhancing perceptual recovery after hearing loss and mitigating hyperacusis and tinnitus.
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Affiliation(s)
- Amanda Henton
- Pittsburgh Hearing Research Center and Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
- Center for Neuroscience, University of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Yanjun Zhao
- Pittsburgh Hearing Research Center and Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Thanos Tzounopoulos
- Pittsburgh Hearing Research Center and Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
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4
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Hernandez CC, Tarfa RA, Miguel I Limcaoco J, Liu R, Mondal P, Hill C, Keith Duncan R, Tzounopoulos T, Stephenson CRJ, O'Meara MJ, Wipf P. Development of an automated screen for Kv7.2 potassium channels and discovery of a new agonist chemotype. Bioorg Med Chem Lett 2022; 71:128841. [PMID: 35671848 PMCID: PMC9469649 DOI: 10.1016/j.bmcl.2022.128841] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/11/2022] [Accepted: 06/01/2022] [Indexed: 01/11/2023]
Abstract
To identify pore domain ligands on Kv7.2 potassium ion channels, we compared wild-type (WT) and W236L mutant Kv7.2 channels in a series of assays with previously validated and novel agonist chemotypes. Positive controls were retigabine, flupirtine, and RL-81; i.e. Kv7.2 channel activators that significantly shift voltage-dependent activation to more negative potentials (ΔV50) at 5 µM. We identified 6 new compounds that exhibited differential enhancing activity between WT and W236L mutant channels. Whole cell patch-clamp electrophysiology studies were conducted to identify Kv7.2. Kv7.2/3, Kv7.4, and Kv7.5 selectivity. Our results validate the SyncroPatch platform and establish new structure activity relationships (SAR). Specifically, in addition to selective Kv7.2, Kv7.2/3, Kv7.4. and Kv7.5 agonists, we identified a novel chemotype, ZK-21, a 4-aminotetrahydroquinoline that is distinct from any of the previously described Kv7 channel modifiers. Using flexible receptor docking, ZK-21 was predicted to be stabilized by W236 and bind perpendicular to retigabine, burying the benzyl carbamate group into a tunnel reaching the core of the pore domain.
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Affiliation(s)
- Ciria C Hernandez
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, United States
| | - Rahilla A Tarfa
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Jose Miguel I Limcaoco
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, United States
| | - Ruiting Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Pravat Mondal
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Clare Hill
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States; Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15213, United States
| | - R Keith Duncan
- Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109, United States
| | - Thanos Tzounopoulos
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Corey R J Stephenson
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, United States
| | - Matthew J O'Meara
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, United States
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States; Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15213, United States; School of Pharmacy, University of Eastern Finland, 70210 Kuopio, Finland
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5
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Musella S, Carotenuto L, Iraci N, Baroli G, Ciaglia T, Nappi P, Basilicata MG, Salviati E, Barrese V, Vestuto V, Pignataro G, Pepe G, Sommella E, Di Sarno V, Manfra M, Campiglia P, Gomez-Monterrey I, Bertamino A, Taglialatela M, Ostacolo C, Miceli F. Beyond Retigabine: Design, Synthesis, and Pharmacological Characterization of a Potent and Chemically Stable Neuronal Kv7 Channel Activator with Anticonvulsant Activity. J Med Chem 2022; 65:11340-11364. [PMID: 35972998 PMCID: PMC9421656 DOI: 10.1021/acs.jmedchem.2c00911] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
![]()
Neuronal Kv7 channels represent important pharmacological
targets
for hyperexcitability disorders including epilepsy. Retigabine is
the prototype Kv7 activator clinically approved for seizure treatment;
however, severe side effects associated with long-term use have led
to its market discontinuation. Building upon the recently described
cryoEM structure of Kv7.2 complexed with retigabine and on previous
structure–activity relationship studies, a small library of
retigabine analogues has been designed, synthesized, and characterized
for their Kv7 opening ability using both fluorescence- and electrophysiology-based
assays. Among all tested compounds, 60 emerged as a potent
and photochemically stable neuronal Kv7 channel activator. Compared
to retigabine, compound 60 displayed a higher brain/plasma
distribution ratio, a longer elimination half-life, and more potent
and effective anticonvulsant effects in an acute seizure model in
mice. Collectively, these data highlight compound 60 as
a promising lead compound for the development of novel Kv7 activators
for the treatment of hyperexcitability diseases.
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Affiliation(s)
- Simona Musella
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Lidia Carotenuto
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Nunzio Iraci
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale Ferdinando Stagno d'Alcontres 31, Messina 98166, Italy
| | - Giulia Baroli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Tania Ciaglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Piera Nappi
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | | | - Emanuela Salviati
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Vincenzo Barrese
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Vincenzo Vestuto
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Giuseppe Pignataro
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Giacomo Pepe
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Eduardo Sommella
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Veronica Di Sarno
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Michele Manfra
- Department of Science, University of Basilicata, Via dell'Ateneo Lucano 10, Potenza 85100, Italy
| | - Pietro Campiglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Isabel Gomez-Monterrey
- Department of Pharmacy, University Federico II of Naples, Via D. Montesano 49, Naples 80131, Italy
| | - Alessia Bertamino
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, Fisciano 84084, Salerno, Italy
| | - Maurizio Taglialatela
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
| | - Carmine Ostacolo
- Department of Pharmacy, University Federico II of Naples, Via D. Montesano 49, Naples 80131, Italy
| | - Francesco Miceli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, Naples 80131, Italy
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6
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Borgini M, Wipf P. Stereoselective synthesis of δ-fluorinated isoleucines exploiting consecutive C(sp3)-H bond activations. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.132876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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7
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Zhang YM, Xu HY, Hu HN, Tian FY, Chen F, Liu HN, Zhan L, Pi XP, Liu J, Gao ZB, Nan FJ. Discovery of HN37 as a Potent and Chemically Stable Antiepileptic Drug Candidate. J Med Chem 2021; 64:5816-5837. [PMID: 33929863 DOI: 10.1021/acs.jmedchem.0c02252] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We previously reported that P-retigabine (P-RTG), a retigabine (RTG) analogue bearing a propargyl group at the nitrogen atom in the linker of RTG, displayed moderate anticonvulsant efficacy. Recently, our further efforts led to the discovery of HN37 (pynegabine), which demonstrated satisfactory chemical stability upon deleting the ortho liable -NH2 group and installing two adjacent methyl groups to the carbamate motif. HN37 exhibited enhanced activation potency toward neuronal Kv7 channels and high in vivo efficacy in a range of pre-clinical seizure models, including the maximal electroshock test and a 6 Hz model of pharmacoresistant limbic seizures. With its improved chemical stability, strong efficacy, and better safety margin, HN37 has progressed to clinical trial in China for epilepsy treatment.
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Affiliation(s)
- Yang-Ming Zhang
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.,Yantai Key Laboratory of Nanomedicine & Advanced Preparations, Yantai Institute of Materia Medica, No. 39, Science and Technology Avenue, High-Tech Industrial Development Zone, Yantai City, Shandong 264000, China
| | - Hai-Yan Xu
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.,School of Chinese Materia Medica, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Qixia District, Nanjing City, Jiangsu 210023, China
| | - Hai-Ning Hu
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Fu-Yun Tian
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Fei Chen
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Hua-Nan Liu
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Li Zhan
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Xiao-Ping Pi
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Jie Liu
- Hainan Haiyao Company Ltd., No. 192, Nanhai Road, Xiuying District, Haikou City, Hainan 570311, China
| | - Zhao-Bing Gao
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.,School of Chinese Materia Medica, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Qixia District, Nanjing City, Jiangsu 210023, China
| | - Fa-Jun Nan
- Chinese National Center for Drug Screening, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.,Yantai Key Laboratory of Nanomedicine & Advanced Preparations, Yantai Institute of Materia Medica, No. 39, Science and Technology Avenue, High-Tech Industrial Development Zone, Yantai City, Shandong 264000, China
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8
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Borgini M, Mondal P, Liu R, Wipf P. Chemical modulation of Kv7 potassium channels. RSC Med Chem 2021; 12:483-537. [PMID: 34046626 PMCID: PMC8128042 DOI: 10.1039/d0md00328j] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/01/2020] [Indexed: 01/10/2023] Open
Abstract
The rising interest in Kv7 modulators originates from their ability to evoke fundamental electrophysiological perturbations in a tissue-specific manner. A large number of therapeutic applications are, in part, based on the clinical experience with two broad-spectrum Kv7 agonists, flupirtine and retigabine. Since precise molecular structures of human Kv7 channel subtypes in closed and open states have only very recently started to emerge, computational studies have traditionally been used to analyze binding modes and direct the development of more potent and selective Kv7 modulators with improved safety profiles. Herein, the synthetic and medicinal chemistry of small molecule modulators and the representative biological properties are summarized. Furthermore, new therapeutic applications supported by in vitro and in vivo assay data are suggested.
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Affiliation(s)
- Matteo Borgini
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Pravat Mondal
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Ruiting Liu
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
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9
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Henton A, Tzounopoulos T. What's the buzz? The neuroscience and the treatment of tinnitus. Physiol Rev 2021; 101:1609-1632. [PMID: 33769102 DOI: 10.1152/physrev.00029.2020] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Tinnitus is a pervasive public health issue that affects ∼15% of the United States population. Similar estimates have also been shown on a global scale, with similar prevalence found in Europe, Asia, and Africa. The severity of tinnitus is heterogeneous, ranging from mildly bothersome to extremely disruptive. In the United States, ∼10-20% of individuals who experience tinnitus report symptoms that severely reduce their quality of life. Due to the huge personal and societal burden, in the last 20 yr a concerted effort on basic and clinical research has significantly advanced our understanding and treatment of this disorder. Yet, neither full understanding, nor cure exists. We know that tinnitus is the persistent involuntary phantom percept of internally generated nonverbal indistinct noises and tones, which in most cases is initiated by acquired hearing loss and maintained only when this loss is coupled with distinct neuronal changes in auditory and extra-auditory brain networks. Yet, the exact mechanisms and patterns of neural activity that are necessary and sufficient for the perceptual generation and maintenance of tinnitus remain incompletely understood. Combinations of animal model and human research will be essential in filling these gaps. Nevertheless, the existing progress in investigating the neurophysiological mechanisms has improved current treatment and highlighted novel targets for drug development and clinical trials. The aim of this review is to thoroughly discuss the current state of human and animal tinnitus research, outline current challenges, and highlight new and exciting research opportunities.
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Affiliation(s)
- A Henton
- Pittsburgh Hearing Research Center and Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania.,Center for Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - T Tzounopoulos
- Pittsburgh Hearing Research Center and Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania.,Center for Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania
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10
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Activation of KCNQ4 as a Therapeutic Strategy to Treat Hearing Loss. Int J Mol Sci 2021; 22:ijms22052510. [PMID: 33801540 PMCID: PMC7958948 DOI: 10.3390/ijms22052510] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 12/14/2022] Open
Abstract
Potassium voltage-gated channel subfamily q member 4 (KCNQ4) is a voltage-gated potassium channel that plays essential roles in maintaining ion homeostasis and regulating hair cell membrane potential. Reduction of the activity of the KCNQ4 channel owing to genetic mutations is responsible for nonsyndromic hearing loss, a typically late-onset, initially high-frequency loss progressing over time. In addition, variants of KCNQ4 have also been associated with noise-induced hearing loss and age-related hearing loss. Therefore, the discovery of small compounds activating or potentiating KCNQ4 is an important strategy for the curative treatment of hearing loss. In this review, we updated the current concept of the physiological role of KCNQ4 in the inner ear and the pathologic mechanism underlying the role of KCNQ4 variants with regard to hearing loss. Finally, we focused on currently developed KCNQ4 activators and their pros and cons, paving the way for the future development of specific KCNQ4 activators as a remedy for hearing loss.
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11
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Marinos L, Kouvaros S, Bizup B, Hambach B, Wipf P, Tzounopoulos T. Transient Delivery of a KCNQ2/3-Specific Channel Activator 1 Week After Noise Trauma Mitigates Noise-Induced Tinnitus. J Assoc Res Otolaryngol 2021; 22:127-139. [PMID: 33575914 DOI: 10.1007/s10162-021-00786-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/06/2021] [Indexed: 12/18/2022] Open
Abstract
Exposure to loud noise can cause hearing loss and tinnitus in mice and humans. In mice, one major underlying mechanism of noise-induced tinnitus is hyperactivity of auditory brainstem neurons, due at least in part, to decreased Kv7.2/3 (KCNQ2/3) potassium channel activity. In our previous studies, we used a reflex-based mouse model of tinnitus and showed that administration of a non-specific KCNQ channel activator, immediately after noise trauma, prevented the development of noise-induced tinnitus, assessed 1 week after trauma. Subsequently, we developed RL-81, a very potent and highly specific activator of KCNQ2/3 channels. Here, to test the timing window within which RL-81 prevents tinnitus in mice, we modified and employed an operant animal model of tinnitus, where mice are trained to move in response to sound but not move in silence. Mice with behavioral evidence of tinnitus are expected to move in silence. We validated this mouse model by testing the effect of salicylate, which is known to induce tinnitus. We found that transient administration of RL-81 1 week after noise exposure did not affect hearing loss but reduced significantly the percentage of mice with behavioral evidence of tinnitus, assessed 2 weeks after noise exposure. Our results indicate that RL-81 is a promising drug candidate for further development for the treatment of noise-induced tinnitus.
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Affiliation(s)
- Laura Marinos
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, 15261, USA
| | - Stylianos Kouvaros
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, 15261, USA
| | - Brandon Bizup
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, 15261, USA
| | - Bryce Hambach
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, 15261, USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Thanos Tzounopoulos
- Department of Otolaryngology, Pittsburgh Hearing Research Center, University of Pittsburgh, Pittsburgh, 15261, USA.
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12
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Liu Y, Bian X, Wang K. Pharmacological Activation of Neuronal Voltage-Gated Kv7/KCNQ/M-Channels for Potential Therapy of Epilepsy and Pain. Handb Exp Pharmacol 2021; 267:231-251. [PMID: 33837465 DOI: 10.1007/164_2021_458] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Native M-current is a low-threshold, slowly activating potassium current that exerts an inhibitory control over neuronal excitability. The M-channel is primarily co-assembled by heterotetrameric Kv7.2/KCNQ2 and Kv7.3/KCNQ3 subunits that are specifically expressed in the brain and peripheral nociceptive and visceral sensory neurons in the spinal cord. Reduction of M-channel function leads to neuronal hyperexcitability that defines the fundamental mechanism of neurological disorders such as epilepsy and pain, indicating that pharmacological activation of Kv7/KCNQ/M-channels may serve the basis for the therapy. The well-known KCNQ opener retigabine (ezogabine or Potiga) was approved by FDA in 2011 as an anticonvulsant used for an adjunctive treatment of partial epilepsies. Unfortunately, retigabine was discontinued in 2017 due to its side effects of blue-colored appearance of the skin and eyes after prolonged intake. In addition, flupirtine, a structural derivative of retigabine and a centrally acting non-opioid analgesic, was also withdrawn in 2018 for liver toxicity. Fortunately, these side effects are compound-structures related and can be avoided. Thus, further identification and development of novel potent and selective Kv7 channel openers may lead to an effective therapy with improved safety window for anti-epilepsy and anti-nociception.
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Affiliation(s)
- Yani Liu
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Xiling Bian
- Department of Pharmacology, Peking University School of Pharmaceutical Sciences, Beijing, China
| | - KeWei Wang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China. .,Institute of Innovative Drugs Qingdao University, Qingdao, China.
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13
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Malysz J, Petkov GV. Detrusor Smooth Muscle K V7 Channels: Emerging New Regulators of Urinary Bladder Function. Front Physiol 2020; 11:1004. [PMID: 33041840 PMCID: PMC7526500 DOI: 10.3389/fphys.2020.01004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 07/23/2020] [Indexed: 01/21/2023] Open
Abstract
Relaxation and contraction of the urinary bladder smooth muscle, also known as the detrusor smooth muscle (DSM), facilitate the micturition cycle. DSM contractility depends on cell excitability, which is established by the synchronized activity of multiple diverse ion channels. K+ channels, the largest family of channels, control DSM excitability by maintaining the resting membrane potential and shaping the action potentials that cause the phasic contractions. Among the members of the voltage-gated K+ (KV) channel superfamily, KV type 7 (KV7) channels - KV7.1-KV7.5 members encoded by KCNQ1-KCNQ5 genes - have been recently identified as functional regulators in various cell types including vascular, cardiac, and neuronal cells. Their regulatory roles in DSM, however, are just now emerging and remain to be elucidated. To address this gap, our research group has initiated the systematic investigation of human DSM KV7 channels in collaboration with clinical urologists. In this comprehensive review, we summarize the current understanding of DSM Kv7 channels and highlight recent discoveries in the field. We describe KV7 channel expression profiles at the mRNA and protein levels, and further elaborate on functional effects of KV7 channel selective modulators on DSM excitability, contractility, and intracellular Ca2+ dynamics in animal species along with in vivo studies and the limited data on human DSM. Within each topic, we highlight the main observations, current gaps in knowledge, and most pressing questions and concepts in need of resolution. We emphasize the lack of systematic studies on human DSM KV7 channels that are now actively ongoing in our laboratory.
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Affiliation(s)
- John Malysz
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Georgi V. Petkov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, United States
- Department of Pharmacology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
- Department of Urology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
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14
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Yang Y, Luo G, Li Y, Tong X, He M, Zeng H, Jiang Y, Liu Y, Zheng Y. Nickel-Catalyzed Reductive Coupling for Transforming Unactivated Aryl Electrophiles into β-Fluoroethylarenes. Chem Asian J 2020; 15:156-162. [PMID: 31755237 DOI: 10.1002/asia.201901490] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 11/21/2019] [Indexed: 01/24/2023]
Abstract
We report herein a facile synthetic method for converting unactivated (hetero)aryl electrophiles into β-fluoroethylated (hetero)arenes via nickel-catalyzed reductive cross-couplings. This coupling reaction features the involvement of FCH2 CH2 radical intermediate rather than β-fluoroethyl manganese species which provides effective solutions to the problematic β-fluoride side eliminations. The practical value of this protocol is further demonstrated by the late-stage modification of several complex ArCl or ArOH-derived bioactive molecules.
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Affiliation(s)
- Yi Yang
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Gen Luo
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Youlin Li
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Xia Tong
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Mengmeng He
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Hongyao Zeng
- College of Chemistry, Leshan Normal University, 778 Binghe Road, Leshan, Sichuan, 614000, China
| | - Yan Jiang
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Yingle Liu
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
| | - Yubin Zheng
- College of Chemistry and Environmental Engineering, Sichuan University of Science&Engineering, 180 Xueyuan Street, Huixing Lu, Zigong, Sichuan, 643000, China
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15
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Ostacolo C, Miceli F, Di Sarno V, Nappi P, Iraci N, Soldovieri MV, Ciaglia T, Ambrosino P, Vestuto V, Lauritano A, Musella S, Pepe G, Basilicata MG, Manfra M, Perinelli DR, Novellino E, Bertamino A, Gomez-Monterrey IM, Campiglia P, Taglialatela M. Synthesis and Pharmacological Characterization of Conformationally Restricted Retigabine Analogues as Novel Neuronal Kv7 Channel Activators. J Med Chem 2019; 63:163-185. [DOI: 10.1021/acs.jmedchem.9b00796] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Carmine Ostacolo
- Department of Pharmacy, University Federico II of Naples, Via D. Montesano 49, 80131 Naples, Italy
| | - Francesco Miceli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, 80131 Naples, Italy
| | - Veronica Di Sarno
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | - Piera Nappi
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, 80131 Naples, Italy
| | - Nunzio Iraci
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | - Maria Virginia Soldovieri
- Department of Medicine and Health Science V. Tiberio, University of Molise, Via F. de Sanctis, 86100 Campobasso, Italy
| | - Tania Ciaglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | - Paolo Ambrosino
- Department of Science and Technology (DST), University of Sannio, Via Port’Arsa 11, 82100 Benevento, Italy
| | - Vincenzo Vestuto
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | - Anna Lauritano
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, 80131 Naples, Italy
| | - Simona Musella
- European Biomedical Research Center (EBRIS), Via Salvatore de Renzi, 3, 84125 Salerno, Salerno, Italy
| | - Giacomo Pepe
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | | | - Michele Manfra
- Department of Science, University of Basilicata, Via dell’Ateneo Lucano 10, 85100 Potenza, Italy
| | - Diego Romano Perinelli
- School of Pharmacy, University of Camerino, Via Gentile III da Varano, 62032 Camerino, Macerata, Italy
| | - Ettore Novellino
- Department of Pharmacy, University Federico II of Naples, Via D. Montesano 49, 80131 Naples, Italy
| | - Alessia Bertamino
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | | | - Pietro Campiglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II 132, 84084 Fisciano, Salerno, Italy
| | - Maurizio Taglialatela
- Department of Neuroscience, Reproductive Sciences and Dentistry, University Federico II of Naples, Via Pansini, 5, 80131 Naples, Italy
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