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McKiernan EC, Herrera-Valdez MA, Marrone DF. A biophysical minimal model to investigate age-related changes in CA1 pyramidal cell electrical activity. PLoS One 2024; 19:e0308809. [PMID: 39231135 PMCID: PMC11373847 DOI: 10.1371/journal.pone.0308809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 07/30/2024] [Indexed: 09/06/2024] Open
Abstract
Aging is a physiological process that is still poorly understood, especially with respect to effects on the brain. There are open questions about aging that are difficult to answer with an experimental approach. Underlying challenges include the difficulty of recording in vivo single cell and network activity simultaneously with submillisecond resolution, and brain compensatory mechanisms triggered by genetic, pharmacologic, or behavioral manipulations. Mathematical modeling can help address some of these questions by allowing us to fix parameters that cannot be controlled experimentally and investigate neural activity under different conditions. We present a biophysical minimal model of CA1 pyramidal cells (PCs) based on general expressions for transmembrane ion transport derived from thermodynamical principles. The model allows directly varying the contribution of ion channels by changing their number. By analyzing the dynamics of the model, we find parameter ranges that reproduce the variability in electrical activity seen in PCs. In addition, increasing the L-type Ca2+ channel expression in the model reproduces age-related changes in electrical activity that are qualitatively and quantitatively similar to those observed in PCs from aged animals. We also make predictions about age-related changes in PC bursting activity that, to our knowledge, have not been reported previously. We conclude that the model's biophysical nature, flexibility, and computational simplicity make it a potentially powerful complement to experimental studies of aging.
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Affiliation(s)
- Erin C McKiernan
- Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
| | - Marco A Herrera-Valdez
- Laboratorio de Dinámica, Biofísica y Fisiología de Sistemas, Departamento de Matemáticas, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
| | - Diano F Marrone
- Department of Psychology, Wilfrid Laurier University, Waterloo, ON, Canada
- McKnight Brain Institute, University of Arizona, Tucson, AZ, United States of America
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2
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Mokrov GV. Multitargeting in cardioprotection: An example of biaromatic compounds. Arch Pharm (Weinheim) 2023; 356:e2300196. [PMID: 37345968 DOI: 10.1002/ardp.202300196] [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: 04/05/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/23/2023]
Abstract
A multitarget drug design approach is actively developing in modern medicinal chemistry and pharmacology, especially with regard to multifactorial diseases such as cardiovascular diseases, cancer, and neurodegenerative diseases. A detailed study of many well-known drugs developed within the single-target approach also often reveals additional mechanisms of their real pharmacological action. One of the multitarget drug design approaches can be the identification of the basic pharmacophore models corresponding to a wide range of the required target ligands. Among such models in the group of cardioprotectors is the linked biaromatic system. This review develops the concept of a "basic pharmacophore" using the biaromatic pharmacophore of cardioprotectors as an example. It presents an analysis of possible biological targets for compounds corresponding to the biaromatic pharmacophore and an analysis of the spectrum of biological targets for the five most known and most studied cardioprotective drugs corresponding to this model, and their involvement in the biological effects of these drugs.
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Experimental factors that impact CaV1.2 channel pharmacology-Effects of recording temperature, charge carrier, and quantification of drug effects on the step and ramp currents elicited by the "step-step-ramp" voltage protocol. PLoS One 2022; 17:e0276995. [PMID: 36417390 PMCID: PMC9683570 DOI: 10.1371/journal.pone.0276995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 10/18/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE CaV1.2 channels contribute to action potential upstroke in pacemaker cells, plateau potential in working myocytes, and initiate excitation-contraction coupling. Understanding drug action on CaV1.2 channels may inform potential impact on cardiac function. However, literature shows large degrees of variability between CaV1.2 pharmacology generated by different laboratories, casting doubt regarding the utility of these data to predict or interpret clinical outcomes. This study examined experimental factors that may impact CaV1.2 pharmacology. EXPERIMENTAL APPROACH Whole cell recordings were made on CaV1.2 overexpression cells. Current was evoked using a "step-step-ramp" waveform that elicited a step and a ramp current. Experimental factors examined were: 1) near physiological vs. room temperature for recording, 2) drug inhibition of the step vs. the ramp current, and 3) Ca2+ vs. Ba2+ as the charge carrier. Eight drugs were studied. KEY RESULTS CaV1.2 current exhibited prominent rundown, exquisite temperature sensitivity, and required a high degree of series resistance compensation to optimize voltage control. Temperature-dependent effects were examined for verapamil and methadone. Verapamil's block potency shifted by up to 4X between room to near physiological temperature. Methadone exhibited facilitatory and inhibitory effects at near physiological temperature, and only inhibitory effect at room temperature. Most drugs inhibited the ramp current more potently than the step current-a preference enhanced when Ba2+ was the charge carrier. The slopes of the concentration-inhibition relationships for many drugs were shallow, temperature-dependent, and differed between the step and the ramp current. CONCLUSIONS AND IMPLICATIONS All experimental factors examined affected CaV1.2 pharmacology. In addition, whole cell CaV1.2 current characteristics-rundown, temperature sensitivity, and impact of series resistance-are also factors that can impact pharmacology. Drug effects on CaV1.2 channels appear more complex than simple pore block mechanism. Normalizing laboratory-specific approaches is key to improve inter-laboratory data reproducibility. Releasing original electrophysiology records is essential to promote transparency and enable the independent evaluation of data quality.
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4
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Anderson CL, Munawar S, Reilly L, Kamp TJ, January CT, Delisle BP, Eckhardt LL. How Functional Genomics Can Keep Pace With VUS Identification. Front Cardiovasc Med 2022; 9:900431. [PMID: 35859585 PMCID: PMC9291992 DOI: 10.3389/fcvm.2022.900431] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 06/09/2022] [Indexed: 01/03/2023] Open
Abstract
Over the last two decades, an exponentially expanding number of genetic variants have been identified associated with inherited cardiac conditions. These tremendous gains also present challenges in deciphering the clinical relevance of unclassified variants or variants of uncertain significance (VUS). This review provides an overview of the advancements (and challenges) in functional and computational approaches to characterize variants and help keep pace with VUS identification related to inherited heart diseases.
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Affiliation(s)
- Corey L. Anderson
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Saba Munawar
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Louise Reilly
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Timothy J. Kamp
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Craig T. January
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Brian P. Delisle
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Lee L. Eckhardt
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
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5
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Mokrov GV. Linked biaromatic compounds as cardioprotective agents. Arch Pharm (Weinheim) 2021; 355:e2100428. [PMID: 34967027 DOI: 10.1002/ardp.202100428] [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: 10/29/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 11/08/2022]
Abstract
Cardiovascular diseases (CVDs) are widespread in the modern world, and their number is constantly growing. For a long time, CVDs have been the leading cause of morbidity and mortality worldwide. Drugs for the treatment of CVD have been developed almost since the beginning of the 20th century, and a large number of effective cardioprotective agents of various classes have been created. Nevertheless, the need for the design and development of new safe drugs for the treatment of CVD remains. Literature data indicate that a huge number of cardioprotective agents of various generations and mechanisms correspond to a single generalized pharmacophore model containing two aromatic nuclei linked by a linear linker. In this regard, we put forward a concept for the design of a new generation of cardioprotective agents with a multitarget mechanism of action within the indicated pharmacophore model. This review is devoted to a generalization of the currently known compounds with cardioprotective properties and corresponding to the pharmacophore model of biaromatic compounds linked by a linear linker. Particular attention is paid to the history of the creation of these drugs, approaches to their design, and analysis of the structure-action relationship within each class.
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Affiliation(s)
- Grigory V Mokrov
- Department of Medicinal Chemistry, FSBI "Zakusov Institute of Pharmacology", Moscow, Russia
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6
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Adams GL, Pall PS, Grauer SM, Zhou X, Ballard JE, Vavrek M, Kraus RL, Morissette P, Li N, Colarusso S, Bianchi E, Palani A, Klein R, John CT, Wang D, Tudor M, Nolting AF, Biba M, Nowak T, Makarov AA, Reibarkh M, Buevich AV, Zhong W, Regalado EL, Wang X, Gao Q, Shahripour A, Zhu Y, de Simone D, Frattarelli T, Pasquini NM, Magotti P, Iaccarino R, Li Y, Solly K, Lee KJ, Wang W, Chen F, Zeng H, Wang J, Regan H, Amin RP, Regan CP, Burgey CS, Henze DA, Sun C, Tellers DM. Development of ProTx-II Analogues as Highly Selective Peptide Blockers of Na v1.7 for the Treatment of Pain. J Med Chem 2021; 65:485-496. [PMID: 34931831 DOI: 10.1021/acs.jmedchem.1c01570] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Inhibitor cystine knot peptides, derived from venom, have evolved to block ion channel function but are often toxic when dosed at pharmacologically relevant levels in vivo. The article describes the design of analogues of ProTx-II that safely display systemic in vivo blocking of Nav1.7, resulting in a latency of response to thermal stimuli in rodents. The new designs achieve a better in vivo profile by improving ion channel selectivity and limiting the ability of the peptides to cause mast cell degranulation. The design rationale, structural modeling, in vitro profiles, and rat tail flick outcomes are disclosed and discussed.
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Affiliation(s)
- Gregory L Adams
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Parul S Pall
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Steven M Grauer
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Xiaoping Zhou
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | | | - Marissa Vavrek
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Richard L Kraus
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | | | - Nianyu Li
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Stefania Colarusso
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Elisabetta Bianchi
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Anandan Palani
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Rebecca Klein
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | | | - Deping Wang
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Matthew Tudor
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Andrew F Nolting
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Mirlinda Biba
- Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Timothy Nowak
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | | | | | | | - Wendy Zhong
- Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | | | - Xiao Wang
- Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Qi Gao
- Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | | | - Yuping Zhu
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Daniele de Simone
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Tommaso Frattarelli
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Nicolo' Maria Pasquini
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Paola Magotti
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Roberto Iaccarino
- Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
| | - Yuxing Li
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Kelli Solly
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Keun-Joong Lee
- Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Weixun Wang
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Feifei Chen
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Haoyu Zeng
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Jixin Wang
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Hilary Regan
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Rupesh P Amin
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | | | | | - Darrell A Henze
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Chengzao Sun
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - David M Tellers
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
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7
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Kowalska M, Fijałkowski Ł, Kubacka M, Sałat K, Grześk G, Nowaczyk J, Nowaczyk A. Antiepileptic Drug Tiagabine Does Not Directly Target Key Cardiac Ion Channels Kv11.1, Nav1.5 and Cav1.2. Molecules 2021; 26:3522. [PMID: 34207748 PMCID: PMC8226520 DOI: 10.3390/molecules26123522] [Citation(s) in RCA: 2] [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: 04/22/2021] [Revised: 06/01/2021] [Accepted: 06/08/2021] [Indexed: 01/08/2023] Open
Abstract
Tiagabine is an antiepileptic drug used for the treatment of partial seizures in humans. Recently, this drug has been found useful in several non-epileptic conditions, including anxiety, chronic pain and sleep disorders. Since tachycardia-an impairment of cardiac rhythm due to cardiac ion channel dysfunction-is one of the most commonly reported non-neurological adverse effects of this drug, in the present paper we have undertaken pharmacological and numerical studies to assess a potential cardiovascular risk associated with the use of tiagabine. A chemical interaction of tiagabine with a model of human voltage-gated ion channels (VGICs) is described using the molecular docking method. The obtained in silico results imply that the adverse effects reported so far in the clinical cardiological of tiagabine could not be directly attributed to its interactions with VGICs. This is also confirmed by the results from the isolated organ studies (i.e., calcium entry blocking properties test) and in vivo (electrocardiogram study) assays of the present research. It was found that tachycardia and other tiagabine-induced cardiac complications are not due to a direct effect of this drug on ventricular depolarization and repolarization.
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Affiliation(s)
- Magdalena Kowalska
- Department of Organic Chemistry, Faculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 87-100 Toruń, Poland; (M.K.); (Ł.F.)
| | - Łukasz Fijałkowski
- Department of Organic Chemistry, Faculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 87-100 Toruń, Poland; (M.K.); (Ł.F.)
| | - Monika Kubacka
- Department of Pharmacodynamics, Chair of Pharmacodynamics, Jagiellonian University Medical College, 9 Medyczna St., 30-688 Krakow, Poland; (M.K.); (K.S.)
| | - Kinga Sałat
- Department of Pharmacodynamics, Chair of Pharmacodynamics, Jagiellonian University Medical College, 9 Medyczna St., 30-688 Krakow, Poland; (M.K.); (K.S.)
| | - Grzegorz Grześk
- Department of Cardiology and Clinical Pharmacology, Faculty of Health Sciences, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 75 Ujejskiego St., 85-168 Bydgoszcz, Poland;
| | - Jacek Nowaczyk
- Physical Chemistry and Chemistry of Polymers, Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarina St., 87-100 Toruń, Poland;
| | - Alicja Nowaczyk
- Department of Organic Chemistry, Faculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 87-100 Toruń, Poland; (M.K.); (Ł.F.)
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8
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Tang F, Yan YM, Yan HL, Wang LX, Hu CJ, Wang HL, Ao H, Peng C, Tan YZ. Chuanxiongdiolides R4 and R5, phthalide dimers with a complex polycyclic skeleton from the aerial parts of Ligusticum chuanxiong and their vasodilator activity. Bioorg Chem 2021; 107:104523. [PMID: 33339668 DOI: 10.1016/j.bioorg.2020.104523] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 11/17/2022]
Abstract
Chuanxiongdiolides R4-R6 (1-3), three novel phthalide dimers featuring two classes of unreported monomeric units (ligustilide/senkyunolide A and ligustilide/neocnidilide) with an unprecedented linkage style (3a,7'/7a,7'a), were isolated from the aerial parts of Ligusticum chuanxiong, together with three pairs of enantiomeric phthalide dimers [(-)/(+)-4a/4b, 5a/5b, and 6a/6b]. The bioassays revealed that compounds 1, 3, 4, 5, and 6 showed significant vasodilation effects, and the mechanism may be attributed to Cav1.2 activation blockade. Based on the established compounds library, the structure activity relationship of the phthalides was proposed. Our findings afford possible leads for developing new vasodilator against cardiovascular and cerebrovascular diseases such as hypertension and ischemic stroke.
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Affiliation(s)
- Fei Tang
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China
| | - Yong-Ming Yan
- School of Pharmaceutical Sciences, Shenzhen University Health Science Center, Shenzhen 518060, People's Republic of China
| | - Hong-Ling Yan
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China
| | - Li-Xia Wang
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China
| | - Chang-Jiang Hu
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China; Key Laboratory of Quality Control and Efficacy Evaluation of Traditional Chinese Medicine Formula Granules, Sichuan New Green Medicine Science and Technology Development Co. Ltd., Pengzhou 611930, People's Republic of China
| | - Hong-Liang Wang
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China
| | - Hui Ao
- Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China.
| | - Cheng Peng
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China.
| | - Yu-Zhu Tan
- State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, People's Republic of China.
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9
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Kowalska M, Nowaczyk J, Nowaczyk A. K V11.1, Na V1.5, and Ca V1.2 Transporter Proteins as Antitarget for Drug Cardiotoxicity. Int J Mol Sci 2020; 21:E8099. [PMID: 33143033 PMCID: PMC7663169 DOI: 10.3390/ijms21218099] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/24/2020] [Accepted: 10/27/2020] [Indexed: 02/07/2023] Open
Abstract
Safety assessment of pharmaceuticals is a rapidly developing area of pharmacy and medicine. The new advanced guidelines for testing the toxicity of compounds require specialized tools that provide information on the tested drug in a quick and reliable way. Ion channels represent the third-largest target. As mentioned in the literature, ion channels are an indispensable part of the heart's work. In this paper the most important information concerning the guidelines for cardiotoxicity testing and the way the tests are conducted has been collected. Attention has been focused on the role of selected ion channels in this process.
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Affiliation(s)
- Magdalena Kowalska
- Department of Organic Chemistry, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-094 Bydgoszcz, Poland;
| | - Jacek Nowaczyk
- Faculty of Chemistry, Nicolaus Copernicus University, 87-100 Toruń, Poland;
| | - Alicja Nowaczyk
- Department of Organic Chemistry, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 85-094 Bydgoszcz, Poland;
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10
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Morissette P, Polak S, Chain A, Zhai J, Imredy JP, Wildey MJ, Travis J, Fitzgerald K, Fanelli P, Passini E, Rodriguez B, Sannajust F, Regan C. Combining an in silico proarrhythmic risk assay with a tPKPD model to predict QTc interval prolongation in the anesthetized guinea pig assay. Toxicol Appl Pharmacol 2020; 390:114883. [PMID: 31981640 PMCID: PMC7322544 DOI: 10.1016/j.taap.2020.114883] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 01/03/2020] [Accepted: 01/14/2020] [Indexed: 12/12/2022]
Abstract
Human-based in silico models are emerging as important tools to study the effects of integrating inward and outward ion channel currents to predict clinical proarrhythmic risk. The aims of this study were 2-fold: 1) Evaluate the capacity of an in silico model to predict QTc interval prolongation in the in vivo anesthetized cardiovascular guinea pig (CVGP) assay for new chemical entities (NCEs) and; 2) Determine if a translational pharmacokinetic/pharmacodynamic (tPKPD) model can improve the predictive capacity. In silico simulations for NCEs were performed using a population of human ventricular action potential (AP) models. PatchXpress® (PX) or high throughput screening (HTS) ion channel data from respectively n = 73 and n = 51 NCEs were used as inputs for the in silico population. These NCEs were also tested in the CVGP (n = 73). An M5 pruned decision tree-based regression tPKPD model was used to evaluate the concentration at which an NCE is liable to prolong the QTc interval in the CVGP. In silico results successfully predicted the QTc interval prolongation outcome observed in the CVGP with an accuracy/specificity of 85%/73% and 75%/77%, when using PX and HTS ion channel data, respectively. Considering the tPKPD predicted concentration resulting in QTc prolongation (EC5%) increased accuracy/specificity to 97%/95% using PX and 88%/97% when using HTS. Our results support that human-based in silico simulations in combination with tPKPD modeling can provide correlative results with a commonly used early in vivo safety assay, suggesting a path toward more rapid NCE assessment with reduced resources, cycle time, and animal use. Cardiac electrophysiological in silico model predicts QTc interval prolongation in the guinea pig. PKPD model predicts relevant QTc interval prolongation concentration in guinea pig. Combining the models improves the accuracy of predicting guinea pig QTc effects. Combining models accelerates assessment of QTc with lower resources and animal use.
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Affiliation(s)
- Pierre Morissette
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA.
| | - Sebastian Polak
- Certara UK Limited, Simcyp Division, Sheffield, UK; Jagiellonian University Medical College, Faculty of Pharmacy, Krakow, Poland
| | - Anne Chain
- Pharmacokinetics, Pharmacodynamics and Drug Metabolism (PPDM), Merck & Co., Inc., Rahway, NJ, USA
| | - Jin Zhai
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
| | - John P Imredy
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
| | - Mary Jo Wildey
- Pharmacology, Screening and Informatics, Merck & Co., Kenilworth, NJ, USA
| | - Jeffrey Travis
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
| | - Kevin Fitzgerald
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
| | - Patrick Fanelli
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
| | - Elisa Passini
- Computational Cardiovascular Science Group, Department of Computer Science, BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Blanca Rodriguez
- Computational Cardiovascular Science Group, Department of Computer Science, BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Frederick Sannajust
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
| | - Christopher Regan
- Safety Assessment & Laboratory Animal Resources (SALAR), Merck & Co., Inc., West Point, PA, USA
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11
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Zeng H, Wang J, Clouse H, Lagrutta A, Sannajust F. Human-induced pluripotent stem cell-derived cardiomyocytes have limited I Ks for repolarization reserve as revealed by specific KCNQ1/KCNE1 blocker. JRSM Cardiovasc Dis 2019; 8:2048004019854919. [PMID: 31217965 PMCID: PMC6558757 DOI: 10.1177/2048004019854919] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 05/06/2019] [Accepted: 05/11/2019] [Indexed: 01/18/2023] Open
Abstract
Objective We investigated if there is IKs, and if there is repolarization
reserve by IKs in human-induced pluripotent stem cell-derived
cardiomyocytes (hiPSC-CMs). Design We used a specific KCNQ1/KCNE1 channel blocker, L-000768673, with an
IC50 of 9 nM, and four hERG-specific blockers, astemizole,
cisapride, dofetilide, and E-4031 to investigate the issue. Results L-000768673 concentration-dependently prolonged feature point duration
(FPD)―a surrogate signal of action potential duration―from 1 to 30 nM
without pacing or paced at 1.2 Hz, resulting from IKs blockade in
hiPSC-CMs. At higher concentrations, the effect of L-000768673 on
IKs was mitigated by its effect on ICa-L,
resulting in shortened FPD, reduced impedance amplitude, and increased
beating rate at 1 µM and above, recapitulating the self-limiting properties
of L-000768673 on action potentials. All four hERG-specific blockers
prolonged FPD as expected. Co-application of L-000768673 at sub-threshold
(0.1 and 0.3 nM) and threshold (1 nM) concentrations failed to
synergistically enhance the effects of hERG blockers on FPD prolongation,
rather it showed additive effects, inconsistent with the repolarization
reserve role of IKs in mature human myocytes that enhanced
IKr response, implying a difference between hiPSC-CMs used in
this study and mature human cardiomyocytes. Conclusion There was IKs current in hiPSC-CMs, and blockade of IKs
current caused prolongation of action potential of hiPSC-CMs. However, we
could not demonstrate any synergistic effects on action potential duration
prolongation of hiPSC-CMs by blocking hERG current and IKs
current simultaneously, implying little or no repolarization reserve by
IKs current in hiPSC-CMs used in this study.
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Affiliation(s)
- Haoyu Zeng
- Merck & Co., Inc., Safety and Exploratory Pharmacology, West Point, PA, USA
| | - Jixin Wang
- Merck & Co., Inc., Safety and Exploratory Pharmacology, West Point, PA, USA
| | - Holly Clouse
- Merck & Co., Inc., Safety and Exploratory Pharmacology, West Point, PA, USA
| | - Armando Lagrutta
- Merck & Co., Inc., Safety and Exploratory Pharmacology, West Point, PA, USA
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12
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Optogenetic Control of Voltage-Gated Calcium Channels. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201713080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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13
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Ma G, Liu J, Ke Y, Liu X, Li M, Wang F, Han G, Huang Y, Wang Y, Zhou Y. Optogenetic Control of Voltage-Gated Calcium Channels. Angew Chem Int Ed Engl 2018; 57:7019-7022. [PMID: 29569306 PMCID: PMC6032918 DOI: 10.1002/anie.201713080] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Indexed: 11/11/2022]
Abstract
Voltage‐gated Ca2+ (CaV) channels mediate Ca2+ entry into excitable cells to regulate a myriad of cellular events following membrane depolarization. We report the engineering of RGK GTPases, a class of genetically encoded CaV channel modulators, to enable photo‐tunable modulation of CaV channel activity in excitable mammalian cells. This optogenetic tool (designated optoRGK) tailored for CaV channels could find broad applications in interrogating a wide range of CaV‐mediated physiological processes.
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Affiliation(s)
- Guolin Ma
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, 2121 W Holcombe Blvd, Houston, TX, 77030, USA
| | - Jindou Liu
- Beijing Key Laboratory of Gene Resource and Molecular, Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yuepeng Ke
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, 2121 W Holcombe Blvd, Houston, TX, 77030, USA
| | - Xin Liu
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, 2121 W Holcombe Blvd, Houston, TX, 77030, USA
| | - Minyong Li
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, School of Pharmacy, Shandong University, Jinan, Shandong, 250012, China
| | - Fen Wang
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, 2121 W Holcombe Blvd, Houston, TX, 77030, USA
| | - Gang Han
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Yun Huang
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, 2121 W Holcombe Blvd, Houston, TX, 77030, USA
| | - Youjun Wang
- Beijing Key Laboratory of Gene Resource and Molecular, Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yubin Zhou
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, 2121 W Holcombe Blvd, Houston, TX, 77030, USA.,Department of Medical Physiology, College of Medicine, Texas A&M University, Temple, TX, 76504, USA
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14
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Comprehensive in vitro Proarrhythmia Assay (C i PA): Pending issues for successful validation and implementation. J Pharmacol Toxicol Methods 2016; 81:21-36. [DOI: 10.1016/j.vascn.2016.05.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 05/21/2016] [Accepted: 05/23/2016] [Indexed: 12/29/2022]
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15
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Lagrutta A, Zeng H, Imredy J, Balasubramanian B, Dech S, Lis E, Wang J, Zhai J, DeGeorge J, Sannajust F. Interaction between amiodarone and hepatitis-C virus nucleotide inhibitors in human induced pluripotent stem cell-derived cardiomyocytes and HEK-293 Cav1.2 over-expressing cells. Toxicol Appl Pharmacol 2016; 308:66-76. [PMID: 27520758 DOI: 10.1016/j.taap.2016.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/20/2016] [Accepted: 08/08/2016] [Indexed: 12/16/2022]
Abstract
Several clinical cases of severe bradyarrhythmias have been reported upon co-administration of the Hepatitis-C NS5B Nucleotide Polymerase Inhibitor (HCV-NI) direct-acting antiviral agent, sofosbuvir (SOF), and the Class-III anti-arrhythmic amiodarone (AMIO). We model the cardiac drug-drug interaction (DDI) between AMIO and SOF, and between AMIO and a closely-related SOF analog, MNI-1 (Merck Nucleotide Inhibitor #1), in functional assays of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), to provide mechanistic insights into recently reported clinical cases. AMIO co-applied with SOF or MNI-1 increased beating rate or field potential (FP) rate and decreased impedance (IMP) and Ca(2+) transient amplitudes in hiPSC-CM syncytia. This action resembled that of Ca(2+) channel blockers (CCBs) in the model, but CCBs did not substitute for AMIO in the DDI. AMIO analog dronedarone (DRON) did not substitute for, but competed with AMIO in the DDI. Ryanodine and thapsigargin, decreasing intracellular Ca(2+) stores, and SEA-0400, a Na(+)/Ca(2+) exchanger-1 (NCX1) inhibitor, partially antagonized or suppressed DDI effects. Other agents affecting FP rate only exerted additive or subtractive effects, commensurate with their individual effects. We also describe an interaction between AMIO and MNI-1 on Cav1.2 ion channels in an over-expressing HEK-293 cell line. MNI-1 enhanced Cav1.2 channel inhibition by AMIO, but did not affect inhibition of Cav1.2 by DRON, verapamil, nifedipine, or diltiazem. Our data in hiPSC-CMs indicate that HCV-NI agents such as SOF and MNI-1 interact with key intracellular Ca(2+)-handling mechanisms. Additional study in a Cav1.2 HEK-293 cell-line suggests that HCV-NIs potentiate the inhibitory action of AMIO on L-type Ca(2+) channels.
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Affiliation(s)
- Armando Lagrutta
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA.
| | - Haoyu Zeng
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - John Imredy
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Bharathi Balasubramanian
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Spencer Dech
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Edward Lis
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Jixin Wang
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Jin Zhai
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Joseph DeGeorge
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
| | - Frederick Sannajust
- Merck Research Laboratories, SALAR Division, Safety & Exploratory Pharmacology (SEP) Department, West Point, PA, USA
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16
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Abstract
Aldosterone-producing adenomas (APAs) vary in phenotype and genotype. Zona
glomerulosa (ZG)-like APAs frequently have mutations of an L-type calcium channel
(LTCC) CaV1.3. Using a novel antagonist of CaV1.3, compound
8, we investigated the role of CaV1.3 on steroidogenesis in
the human adrenocortical cell line, H295R, and in primary human adrenal cells. This
investigational drug was compared with the common antihypertensive drug nifedipine,
which has 4.5-fold selectivity for the vascular LTCC, CaV1.2, over
CaV1.3. In H295R cells transfected with wild-type or mutant
CaV1.3 channels, the latter produced more aldosterone than wild-type,
which was ameliorated by 100 μM of compound 8. In primary
adrenal and non-transfected H295R cells, compound 8 decreased aldosterone
production similar to high concentration of nifedipine (100 μM).
Selective CaV1.3 blockade may offer a novel way of treating primary
hyperaldosteronism, which avoids the vascular side effects of
CaV1.2-blockade, and provides targeted treatment for ZG-like APAs with
mutations of CaV1.3.
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17
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Zamponi GW. Targeting voltage-gated calcium channels in neurological and psychiatric diseases. Nat Rev Drug Discov 2015; 15:19-34. [DOI: 10.1038/nrd.2015.5] [Citation(s) in RCA: 254] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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18
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Predicting changes in cardiac myocyte contractility during early drug discovery with in vitro assays. Toxicol Appl Pharmacol 2014; 279:87-94. [DOI: 10.1016/j.taap.2014.06.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/12/2014] [Accepted: 06/07/2014] [Indexed: 11/22/2022]
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19
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Kuryshev YA, Brown AM, Duzic E, Kirsch GE. Evaluating state dependence and subtype selectivity of calcium channel modulators in automated electrophysiology assays. Assay Drug Dev Technol 2014; 12:110-9. [PMID: 24579774 PMCID: PMC4657039 DOI: 10.1089/adt.2013.552] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Voltage-gated Ca2+ channels play essential roles in control of neurosecretion and muscle contraction. The pharmacological significance of Cav channels stem from their identification as the molecular targets of calcium blockers used in the treatment of cardiovascular diseases, such as hypertension, angina, and arrhythmia, and neurologic diseases, such as pain and seizure. It has been proposed that state-dependent Cav inhibitors, that is, those that preferentially bind to channels in open or inactivated states, may improve the therapeutic window over relatively state-independent Cav inhibitors. High-throughput fluorescent-based functional assays have been useful in screening chemical libraries to identify Cav inhibitors. However, hit confirmation, mechanism of action, and subtype selectivity are better suited to automated patch clamp assays that have sufficient capacity to handle the volume of compounds identified during screening, even of modest sized libraries (≤500,000 compounds), and the flexible voltage control that allows evaluation of state-dependent drug blocks. IonWorks Barracuda (IWB), the newest generation of IonWorks instruments, provides the opportunity to accelerate the Cav drug discovery studies in an automated patch clamp platform in 384-well format capable of medium throughput screening and profiling studies. We have validated hCav1.2, hCav2.1, hCav2.2, and hCav3.2 channels assays on the IWB platform (population patch clamp mode) and demonstrated that the biophysical characteristics of the channels (activation, inactivation, and steady-state inactivation) obtained with the IWB system are consistent with known subtype-specific characteristics. Using standard reference compounds (nifedipine, BAY K8644, verapamil, mibefradil, and pimozide), we demonstrated subtype-selective and state- and use-dependent characteristics of drug-channel interactions. Here we describe the design and validation of novel robust high-throughput Cav channel assays on the IWB platform. The assays can be used to screen focused compound libraries for state-dependent Cav channel antagonists, to prioritize compounds for potency or to counterscreen for Cav subtype selectivity.
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20
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Townsend C, Brown BS. Predicting drug-induced QT prolongation and torsades de pointes: a review of preclinical endpoint measures. ACTA ACUST UNITED AC 2013; Chapter 10:Unit 10.16. [PMID: 23744708 DOI: 10.1002/0471141755.ph1016s61] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Compound-induced prolongation of the cardiac QT interval is a major concern in drug development and this unit discusses approaches that can predict QT effects prior to undertaking clinical trials. The majority of compounds that prolong the QT interval block the cardiac rapid delayed rectifier potassium current, IKr (hERG). Described in this overview are different ways to measure hERG, from recent advances in automated electrophysiology to the quantification of channel protein trafficking and binding. The contribution of other cardiac ion channels to hERG data interpretation is also discussed. In addition, endpoint measures of the integrated activity of cardiac ion channels at the single-cell, tissue, and whole-animal level, including for example the well-established action potential to the more recent beat-to-beat variability, transmural dispersion of repolarization, and field potential duration, are described in the context of their ability to predict QT prolongation and torsadogenicity in humans.
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Affiliation(s)
- Claire Townsend
- GlaxoSmithKline Biological Reagents and Assay Development, Research Triangle Park, NC, USA
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21
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Morissette P, Nishida M, Trepakova E, Imredy J, Lagrutta A, Chaves A, Hoagland K, Hoe CML, Zrada MM, Travis JJ, Zingaro GJ, Gerenser P, Friedrichs G, Salata JJ. The anesthetized guinea pig: An effective early cardiovascular derisking and lead optimization model. J Pharmacol Toxicol Methods 2013; 68:137-49. [DOI: 10.1016/j.vascn.2013.04.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 04/19/2013] [Accepted: 04/27/2013] [Indexed: 10/26/2022]
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22
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Zhang XF, Zhang D, Surowy CS, Yao B, Jarvis MF, McGaraughty S, Neelands TR. Development and validation of a medium-throughput electrophysiological assay for KCNQ2/3 channel openers using QPatch HT. Assay Drug Dev Technol 2012; 11:17-24. [PMID: 23002961 DOI: 10.1089/adt.2012.446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The KCNQ2/3 channel has emerged as a drug target for a number of neurological disorders including pain and epilepsy. Known KCNQ2/3 openers have effects on two distinct biophysical properties of the channel: (1) a hyperpolarizing shift in the voltage dependence of channel activation (V(1/2)), and (2) an increase in channel open probability or peak whole-cell current. The current high-throughput screening assays for KCNQ2/3 openers measure changes of channel activity at sub-peak conductances and the output measure is a combination of effects on V(1/2) shift and peak current. Here, we describe a medium-throughput electrophysiological assay for screening KCNQ2/3 openers using the QPatch HT platform. We employed a double-pulse protocol that measures the shift in V(1/2) and the change in current amplitude at peak conductance voltage. Retigabine along with novel KCNQ2/3 openers were evaluated in this assay. Three classes of KCNQ2/3 openers were identified based on the hyperpolarizing shift in V(1/2) and the change in peak current. All three classes of compounds caused a hyperpolarizing shift in V(1/2), but they were differentiated by their respective effects on peak current amplitude (increase, decrease, or only modestly affecting peak current amplitude). KCNQ2/3 blockers were also identified with this assay. These compounds blocked currents without affecting voltage-dependent activation. In summary, we have developed a medium-throughput assay that can reliably detect changes in the biophysical properties of the KCNQ2/3 channel, V(1/2), and peak current amplitude, and therefore may serve as a reliable assay to evaluate KCNQ2/3 openers and blockers.
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Affiliation(s)
- Xu-Feng Zhang
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois 60064-6125, USA.
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23
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Abassi YA, Xi B, Li N, Ouyang W, Seiler A, Watzele M, Kettenhofen R, Bohlen H, Ehlich A, Kolossov E, Wang X, Xu X. Dynamic monitoring of beating periodicity of stem cell-derived cardiomyocytes as a predictive tool for preclinical safety assessment. Br J Pharmacol 2012; 165:1424-41. [PMID: 21838757 DOI: 10.1111/j.1476-5381.2011.01623.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Cardiac toxicity is a major concern in drug development and it is imperative that clinical candidates are thoroughly tested for adverse effects earlier in the drug discovery process. In this report, we investigate the utility of an impedance-based microelectronic detection system in conjunction with mouse embryonic stem cell-derived cardiomyocytes for assessment of compound risk in the drug discovery process. EXPERIMENTAL APPROACH Beating of cardiomyocytes was measured by a recently developed microelectronic-based system using impedance readouts. We used mouse stem cell-derived cardiomyocytes to obtain dose-response profiles for over 60 compounds, including ion channel modulators, chronotropic/ionotropic agents, hERG trafficking inhibitors and drugs known to induce Torsades de Pointes arrhythmias. KEY RESULTS This system sensitively and quantitatively detected effects of modulators of cardiac function, including some compounds missed by electrophysiology. Pro-arrhythmic compounds produced characteristic profiles reflecting arrhythmia, which can be used for identification of other pro-arrhythmic compounds. The time series data can be used to identify compounds that induce arrhythmia by complex mechanisms such as inhibition of hERG channels trafficking. Furthermore, the time resolution allows for assessment of compounds that simultaneously affect both beating and viability of cardiomyocytes. CONCLUSIONS AND IMPLICATIONS Microelectronic monitoring of stem cell-derived cardiomyocyte beating provides a high throughput, quantitative and predictive assay system that can be used for assessment of cardiac liability earlier in the drug discovery process. The convergence of stem cell technology with microelectronic monitoring should facilitate cardiac safety assessment.
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24
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Morton MJ, Main MJ. Use of escin as a perforating agent on the IonWorks quattro automated electrophysiology platform. ACTA ACUST UNITED AC 2012; 18:128-34. [PMID: 22923788 DOI: 10.1177/1087057112456599] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The automated electrophysiology platform IonWorks has facilitated the medium-throughput study of ion channel biology and pharmacology. Electrical and chemical access to the cell is by perforated patch, afforded by amphotericin. Permeation of the amphotericin pore is limited to monovalent cations. We describe here the use of the saponin escin as an alternative perforating agent. With respect to the number and robustness of seals formed across a variety of cell and ion channel types, the performance of escin is equal to that of amphotericin. Escin also permits the permeation of larger molecules through its pore. These include nucleotides, important intracellular modulators of ion channel activity that can be used to prevent ion channel rundown of, for instance, Ca(V)1.2. Furthermore, pharmacologic agents such as QX314 can also permeate and be used for mechanistic studies. Escin, in combination with IonWorks, increases the scope of ion channel screening and can facilitate the assay of previously difficult-to-assay targets.
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Affiliation(s)
- Michael J Morton
- Global Ion Channel Initiative, AstraZeneca UK, R&D Alderley Park, Macclesfield, UK.
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25
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Möller C, Witchel H. Automated electrophysiology makes the pace for cardiac ion channel safety screening. Front Pharmacol 2011; 2:73. [PMID: 22131974 PMCID: PMC3222877 DOI: 10.3389/fphar.2011.00073] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 11/06/2011] [Indexed: 01/14/2023] Open
Abstract
The field of automated patch-clamp electrophysiology has emerged from the tension between the pharmaceutical industry’s need for high-throughput compound screening versus its need to be conservative due to regulatory requirements. On the one hand, hERG channel screening was increasingly requested for new chemical entities, as the correlation between blockade of the ion channel coded by hERG and torsades de pointes cardiac arrhythmia gained increasing attention. On the other hand, manual patch-clamping, typically quoted as the “gold-standard” for understanding ion channel function and modulation, was far too slow (and, consequently, too expensive) for keeping pace with the numbers of compounds submitted for hERG channel investigations from pharmaceutical R&D departments. In consequence it became more common for some pharmaceutical companies to outsource safety pharmacological investigations, with a focus on hERG channel interactions. This outsourcing has allowed those pharmaceutical companies to build up operational flexibility and greater independence from internal resources, and allowed them to obtain access to the latest technological developments that emerged in automated patch-clamp electrophysiology – much of which arose in specialized biotech companies. Assays for nearly all major cardiac ion channels are now available by automated patch-clamping using heterologous expression systems, and recently, automated action potential recordings from stem-cell derived cardiomyocytes have been demonstrated. Today, most of the large pharmaceutical companies have acquired automated electrophysiology robots and have established various automated cardiac ion channel safety screening assays on these, in addition to outsourcing parts of their needs for safety screening.
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Affiliation(s)
- Clemens Möller
- InViTe Research Institute, Albstadt-Sigmaringen University Sigmaringen, Germany
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26
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Cao X, Lee YT, Holmqvist M, Lin Y, Ni Y, Mikhailov D, Zhang H, Hogan C, Zhou L, Lu Q, Digan ME, Urban L, Erdemli G. Cardiac ion channel safety profiling on the IonWorks Quattro automated patch clamp system. Assay Drug Dev Technol 2010; 8:766-80. [PMID: 21133679 DOI: 10.1089/adt.2010.0333] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The normal electrophysiologic behavior of the heart is determined by the integrated activity of specific cardiac ionic currents. Mutations in genes encoding the molecular components of individual cardiac ion currents have been shown to result in multiple cardiac arrhythmia syndromes. Presently, 12 genes associated with inherited long QT syndrome (LQTS) have been identified, and the most common mutations are in the hKCNQ1 (LQT1, Jervell and Lange-Nielson syndrome), hKCNH2 (LQT2), and hSCN5A (LQT3, Brugada syndrome) genes. Several drugs have been withdrawn from the market or received black box labeling due to clinical cases of QT interval prolongation, ventricular arrhythmias, and sudden death. Other drugs have been denied regulatory approval owing to their potential for QT interval prolongation. Further, off-target activity of drugs on cardiac ion channels has been shown to be associated with increased mortality in patients with underlying cardiovascular diseases. Since clinical arrhythmia risk is a major cause for compound termination, preclinical profiling for off-target cardiac ion channel interactions early in the drug discovery process has become common practice in the pharmaceutical industry. In the present study, we report assay development for three cardiac ion channels (hKCNQ1/minK, hCa(v)1.2, and hNa(v)1.5) on the IonWorks Quattro™ system. We demonstrate that these assays can be used as reliable pharmacological profiling tools for cardiac ion channel inhibition to assess compounds for cardiac liability during drug discovery.
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Affiliation(s)
- Xueying Cao
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Sciences Inc., Cambridge, Massachusetts 02139, USA
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27
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Penniman JR, Kim DC, Salata JJ, Imredy JP. Assessing use-dependent inhibition of the cardiac Na(+/-) current (I(Na)) in the PatchXpress automated patch clamp. J Pharmacol Toxicol Methods 2010; 62:107-18. [PMID: 20601018 DOI: 10.1016/j.vascn.2010.06.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2010] [Accepted: 06/14/2010] [Indexed: 11/28/2022]
Abstract
INTRODUCTION The cardiac Na+ current (I(Na)) underlies the rapid depolarization of the cardiac myocyte, and block of the current slows cardiac conduction and increases the risk of ventricular arrhythmia. A feature of Na+ channel block termed use-dependence is important to the assessment of blocking potency. We developed a robust automated patch clamp assay to rapidly and routinely assess the use-dependent block of I(Na) by drug candidates. The assay clarifies whether drug candidates block more potently at increased heart rates and provides a quantitative score of use-dependence. METHODS A use-dependent cardiac I(Na) assay was implemented on the PatchXpress 7000A, an automated whole-cell patch clamp device, using a HEK cell line stably expressing the human cardiac Na+ channel, Na(V)1.5. Stable recordings lasting up to 30 minutes were achieved by selection of holding potential (-100 mV) as well as an appropriate osmotic gradient to prevent time-dependent loss of cell capacitance and current. The final protocol allows evaluation of I(Na) inhibition at three pulsing rates at three test concentrations for each recorded cell. RESULTS IC(50) values obtained for three standard I(Na) blockers lidocaine, mexiletine, and flecainide, at pulsing frequencies of 0.2 Hz, 1 Hz, and 3 Hz, were compared to IC(50) values obtained with conventional pipette patch clamp of the Na(V)1.5 cell line and of guinea pig cardiac myocytes using matched voltage protocols and pulsing rates. Absolute potencies were well correlated only under conditions of matched holding potential and fell within an approximately three-fold window. While absolute potencies could vary widely with holding potential, the fold increases in potency with increases in pulsing rates were less prone to variation of the holding potential. DISCUSSION Use-dependence of cardiac Na+ channel block can be rapidly assessed in the PatchXpress platform and quantified at early stages of drug development to guide lead optimization.
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Affiliation(s)
- Jacob R Penniman
- Safety and Exploratory Pharmacology, Safety Assessment, Merck Research Laboratories West Point, PA 19486, USA
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28
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Abstract
For every movement, heartbeat and thought, ion channels need to open and close. It is therefore not surprising that their malfunctioning leads to serious diseases. Currently, only approximately 10% of drugs, with a market value in excess of US$10 billion, act on ion channels. The systematic exploitation of this target class has started, enabled by novel assay technologies and fundamental advances of the structural and mechanistic understanding of channel function. The latter, which was rewarded with the Nobel Prize in 2003, has opened up an avenue for rational drug design. In this review we provide an overview of the current repertoire of screening technologies that has evolved to drive ion channel-targeted drug discovery towards new medicines of the future.
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