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Voldřich J, Matoušová M, Šmídková M, Mertlíková‐Kaiserová H. Fluorescence-Based HTS Assays for Ion Channel Modulation in Drug Discovery Pipelines. ChemMedChem 2024; 19:e202400383. [PMID: 39221492 PMCID: PMC11648840 DOI: 10.1002/cmdc.202400383] [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: 05/20/2024] [Revised: 08/26/2024] [Accepted: 08/28/2024] [Indexed: 09/04/2024]
Abstract
Ion channels represent a druggable family of transmembrane pore-forming proteins with important (patho)physiological functions. While electrophysiological measurement (manual patch clamp) remains the only direct method for detection of ion currents, it is a labor-intensive technique. Although automated patch clamp instruments have become available to date, their high costs limit their use to large pharma companies or commercial screening facilities. Therefore, fluorescence-based assays are particularly important for initial screening of compound libraries. Despite their numerous disadvantages, they are highly amenable to high-throughput screening and in many cases, no sophisticated instrumentation or materials are required. These features predispose them for implementation in early phases of drug discovery pipelines (hit identification), even in an academic environment. This review summarizes the advantages and pitfalls of individual methodological approaches for identification of ion channel modulators employing fluorescent probes (i. e., membrane potential and ion flux assays) with emphasis on practical aspects of their adaptation to high-throughput format.
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Affiliation(s)
- Jan Voldřich
- Institute of Organic Chemistry and BiochemistryAcademy of Sciences of the Czech RepublicFlemingovo nam. 2Prague 6 – Dejvice16610Czech Republic
- University of Chemistry and TechnologyTechnická 5Prague 6 – Dejvice166 28Czech Republic
| | - Marika Matoušová
- Institute of Organic Chemistry and BiochemistryAcademy of Sciences of the Czech RepublicFlemingovo nam. 2Prague 6 – Dejvice16610Czech Republic
| | - Markéta Šmídková
- Institute of Organic Chemistry and BiochemistryAcademy of Sciences of the Czech RepublicFlemingovo nam. 2Prague 6 – Dejvice16610Czech Republic
| | - Helena Mertlíková‐Kaiserová
- Institute of Organic Chemistry and BiochemistryAcademy of Sciences of the Czech RepublicFlemingovo nam. 2Prague 6 – Dejvice16610Czech Republic
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2
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Liu J, Khan MKH, Guo W, Dong F, Ge W, Zhang C, Gong P, Patterson TA, Hong H. Machine learning and deep learning approaches for enhanced prediction of hERG blockade: a comprehensive QSAR modeling study. Expert Opin Drug Metab Toxicol 2024; 20:665-684. [PMID: 38968091 DOI: 10.1080/17425255.2024.2377593] [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: 02/27/2024] [Accepted: 06/26/2024] [Indexed: 07/07/2024]
Abstract
BACKGROUND Cardiotoxicity is a major cause of drug withdrawal. The hERG channel, regulating ion flow, is pivotal for heart and nervous system function. Its blockade is a concern in drug development. Predicting hERG blockade is essential for identifying cardiac safety issues. Various QSAR models exist, but their performance varies. Ongoing improvements show promise, necessitating continued efforts to enhance accuracy using emerging deep learning algorithms in predicting potential hERG blockade. STUDY DESIGN AND METHOD Using a large training dataset, six individual QSAR models were developed. Additionally, three ensemble models were constructed. All models were evaluated using 10-fold cross-validations and two external datasets. RESULTS The 10-fold cross-validations resulted in Mathews correlation coefficient (MCC) values from 0.682 to 0.730, surpassing the best-reported model on the same dataset (0.689). External validations yielded MCC values from 0.520 to 0.715 for the first dataset, exceeding those of previously reported models (0-0.599). For the second dataset, MCC values fell between 0.025 and 0.215, aligning with those of reported models (0.112-0.220). CONCLUSIONS The developed models can assist the pharmaceutical industry and regulatory agencies in predicting hERG blockage activity, thereby enhancing safety assessments and reducing the risk of adverse cardiac events associated with new drug candidates.
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Affiliation(s)
- Jie Liu
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
| | - Md Kamrul Hasan Khan
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
| | - Wenjing Guo
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
| | - Fan Dong
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
| | - Weigong Ge
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
| | - Chaoyang Zhang
- School of Computing Sciences and Computer Engineering, University of Southern Mississippi, Hattiesburg, MS, USA
| | - Ping Gong
- Environmental Laboratory, US Army Engineer Research and Development Center, Vicksburg, MS, USA
| | - Tucker A Patterson
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
| | - Huixiao Hong
- National Center for Toxicological Research, US Food & Drug Administration, Jefferson, AR, USA
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3
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Hsiao Y, Su BH, Tseng YJ. Current development of integrated web servers for preclinical safety and pharmacokinetics assessments in drug development. Brief Bioinform 2020; 22:5881374. [PMID: 32770190 DOI: 10.1093/bib/bbaa160] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/22/2020] [Accepted: 06/24/2020] [Indexed: 12/27/2022] Open
Abstract
In drug development, preclinical safety and pharmacokinetics assessments of candidate drugs to ensure the safety profile are a must. While in vivo and in vitro tests are traditionally used, experimental determinations have disadvantages, as they are usually time-consuming and costly. In silico predictions of these preclinical endpoints have each been developed in the past decades. However, only a few web-based tools have integrated different models to provide a simple one-step platform to help researchers thoroughly evaluate potential drug candidates. To efficiently achieve this approach, a platform for preclinical evaluation must not only predict key ADMET (absorption, distribution, metabolism, excretion and toxicity) properties but also provide some guidance on structural modifications to improve the undesired properties. In this review, we organized and compared several existing integrated web servers that can be adopted in preclinical drug development projects to evaluate the subject of interest. We also introduced our new web server, Virtual Rat, as an alternative choice to profile the properties of drug candidates. In Virtual Rat, we provide not only predictions of important ADMET properties but also possible reasons as to why the model made those structural predictions. Multiple models were implemented into Virtual Rat, including models for predicting human ether-a-go-go-related gene (hERG) inhibition, cytochrome P450 (CYP) inhibition, mutagenicity (Ames test), blood-brain barrier penetration, cytotoxicity and Caco-2 permeability. Virtual Rat is free and has been made publicly available at https://virtualrat.cmdm.tw/.
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Weaver CD. Thallium Flux Assay for Measuring the Activity of Monovalent Cation Channels and Transporters. Methods Mol Biol 2018; 1684:105-114. [PMID: 29058187 DOI: 10.1007/978-1-4939-7362-0_9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Monovalent cation channels are critically important for physiological processes ranging from the control of neuronal excitability to the maintenance of solute balance. Mutations in these channels are associated with a multiplicity of diseases and monovalent cation channel-modulating drugs are used as therapeutics. Techniques that allow the measurement of the activity of these ion channels are useful for exploring their many biological roles as well as enabling the discovery and characterization of ion channel modulators for the purposes of drug discovery. Although there are numerous techniques for measuring the activity of monovalent cation channels, the thallium flux assay technique is a widely used fluorescence-based approach. Described herein is a method for using the thallium-flux technique for detecting and quantifying the activity of small-molecule potassium channel modulators in 384-well plates.
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Affiliation(s)
- C David Weaver
- Department of Pharmacology, Institute of Chemical Biology, Vanderbilt University School of Medicine, 461 Preston Research Bldg., 2222 Piece Ave, Nashville, TN, 37232, USA.
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5
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Aggarwal A, Parai MK, Shetty N, Wallis D, Woolhiser L, Hastings C, Dutta NK, Galaviz S, Dhakal RC, Shrestha R, Wakabayashi S, Walpole C, Matthews D, Floyd D, Scullion P, Riley J, Epemolu O, Norval S, Snavely T, Robertson GT, Rubin EJ, Ioerger TR, Sirgel FA, van der Merwe R, van Helden PD, Keller P, Böttger EC, Karakousis PC, Lenaerts AJ, Sacchettini JC. Development of a Novel Lead that Targets M. tuberculosis Polyketide Synthase 13. Cell 2017; 170:249-259.e25. [PMID: 28669536 PMCID: PMC5509550 DOI: 10.1016/j.cell.2017.06.025] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/03/2017] [Accepted: 06/15/2017] [Indexed: 12/01/2022]
Abstract
Widespread resistance to first-line TB drugs is a major problem that will likely only be resolved through the development of new drugs with novel mechanisms of action. We have used structure-guided methods to develop a lead molecule that targets the thioesterase activity of polyketide synthase Pks13, an essential enzyme that forms mycolic acids, required for the cell wall of Mycobacterium tuberculosis. Our lead, TAM16, is a benzofuran class inhibitor of Pks13 with highly potent in vitro bactericidal activity against drug-susceptible and drug-resistant clinical isolates of M. tuberculosis. In multiple mouse models of TB infection, TAM16 showed in vivo efficacy equal to the first-line TB drug isoniazid, both as a monotherapy and in combination therapy with rifampicin. TAM16 has excellent pharmacological and safety profiles, and the frequency of resistance for TAM16 is ∼100-fold lower than INH, suggesting that it can be developed as a new antitubercular aimed at the acute infection. PAPERCLIP.
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Affiliation(s)
- Anup Aggarwal
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Maloy K Parai
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Nishant Shetty
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Deeann Wallis
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Lisa Woolhiser
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Courtney Hastings
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Noton K Dutta
- Center for Tuberculosis Research, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Stacy Galaviz
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Ramesh C Dhakal
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Rupesh Shrestha
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Shoko Wakabayashi
- Department of Immunology and Infectious Disease, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Chris Walpole
- Structure-guided Drug Discovery Coalition, SGC Toronto, ON, Canada
| | - David Matthews
- Structure-guided Drug Discovery Coalition, SGC Toronto, ON, Canada
| | - David Floyd
- Structure-guided Drug Discovery Coalition, SGC Toronto, ON, Canada
| | - Paul Scullion
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, UK
| | - Jennifer Riley
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, UK
| | - Ola Epemolu
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, UK
| | - Suzanne Norval
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, UK
| | - Thomas Snavely
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Gregory T Robertson
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Eric J Rubin
- Department of Immunology and Infectious Disease, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Thomas R Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, TX, USA
| | - Frik A Sirgel
- NRF Centre of Excellence for Biomedical TB Research and the South African MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Stellenbosch University, Tygerberg, South Africa
| | - Ruben van der Merwe
- NRF Centre of Excellence for Biomedical TB Research and the South African MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Stellenbosch University, Tygerberg, South Africa
| | - Paul D van Helden
- NRF Centre of Excellence for Biomedical TB Research and the South African MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Stellenbosch University, Tygerberg, South Africa
| | - Peter Keller
- Institute of Medical Microbiology, National Center for Mycobacteria, University of Zurich, Zurich, Switzerland
| | - Erik C Böttger
- Institute of Medical Microbiology, National Center for Mycobacteria, University of Zurich, Zurich, Switzerland
| | - Petros C Karakousis
- Center for Tuberculosis Research, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Anne J Lenaerts
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - James C Sacchettini
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA.
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Hampton C, Zhou X, Priest BT, Pai LY, Felix JP, Thomas-Fowlkes B, Liu J, Kohler M, Xiao J, Corona A, Price O, Gill C, Shah K, Rasa C, Tong V, Owens K, Ormes J, Tang H, Roy S, Sullivan KA, Metzger JM, Alonso-Galicia M, Kaczorowski GJ, Pasternak A, Garcia ML. The Renal Outer Medullary Potassium Channel Inhibitor, MK-7145, Lowers Blood Pressure, and Manifests Features of Bartter's Syndrome Type II Phenotype. J Pharmacol Exp Ther 2016; 359:194-206. [PMID: 27432892 DOI: 10.1124/jpet.116.235150] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/14/2016] [Indexed: 03/08/2025] Open
Abstract
The renal outer medullary potassium (ROMK) channel, located at the apical surface of epithelial cells in the thick ascending loop of Henle and cortical collecting duct, contributes to salt reabsorption and potassium secretion, and represents a target for the development of new mechanism of action diuretics. This idea is supported by the phenotype of antenatal Bartter's syndrome type II associated with loss-of-function mutations in the human ROMK channel, as well as, by cardiovascular studies of heterozygous carriers of channel mutations associated with type II Bartter's syndrome. Although the pharmacology of ROMK channels is still being developed, channel inhibitors have been identified and shown to cause natriuresis and diuresis, in the absence of any significant kaliuresis, on acute oral dosing to rats or dogs. Improvements in potency and selectivity have led to the discovery of MK-7145 [5,5'-((1R,1'R)-piperazine-1,4-diylbis(1-hydroxyethane-2,1-diyl))bis(4-methylisobenzofuran-1(3H)-one)], a potential clinical development candidate. In spontaneously hypertensive rats, oral dosing of MK-7145 causes dose-dependent lowering of blood pressure that is maintained during the entire treatment period, and that displays additive/synergistic effects when administered in combination with hydrochlorothiazide or candesartan, respectively. Acute or chronic oral administration of MK-7145 to normotensive dogs led to dose-dependent diuresis and natriuresis, without any significant urinary potassium losses or changes in plasma electrolyte levels. Elevations in bicarbonate and aldosterone were found after 6 days of dosing. These data indicate that pharmacological inhibition of ROMK has potential as a new mechanism for the treatment of hypertension and/or congestive heart failure. In addition, Bartter's syndrome type II features are manifested on exposure to ROMK inhibitors.
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Affiliation(s)
- Caryn Hampton
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Xiaoyan Zhou
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Birgit T Priest
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Lee-Yuh Pai
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - John P Felix
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Brande Thomas-Fowlkes
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Jessica Liu
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Martin Kohler
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Jianying Xiao
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Aaron Corona
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Olga Price
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Charles Gill
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Kashmira Shah
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Cordelia Rasa
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Vince Tong
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Karen Owens
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - James Ormes
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Haifeng Tang
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Sophie Roy
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Kathleen A Sullivan
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Joseph M Metzger
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Magdalena Alonso-Galicia
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Gregory J Kaczorowski
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Alexander Pasternak
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
| | - Maria L Garcia
- Departments of Hypertension (C.H., X.Z., L.-Y.P., J.X., A.C., O.P., C.G., K.S., C.R., S.R., K.A.S., J.M.M., M.A.-G.), Ion Channels (B.T.P., J.P.F., B.T.-F., J.L., M.K., G.J.K., M.L.G.), Drug Metabolism (V.T., K.O., J.O.), and Medicinal Chemistry (H.T., A.P.), Merck Research Laboratories, Kenilworth, New Jersey
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7
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Takemoto Y, Ramirez RJ, Yokokawa M, Kaur K, Ponce-Balbuena D, Sinno MC, Willis BC, Ghanbari H, Ennis SR, Guerrero-Serna G, Henzi BC, Latchamsetty R, Ramos-Mondragon R, Musa H, Martins RP, Pandit SV, Noujaim SF, Crawford T, Jongnarangsin K, Pelosi F, Bogun F, Chugh A, Berenfeld O, Morady F, Oral H, Jalife J. Galectin-3 Regulates Atrial Fibrillation Remodeling and Predicts Catheter Ablation Outcomes. JACC Basic Transl Sci 2016; 1:143-154. [PMID: 27525318 PMCID: PMC4979747 DOI: 10.1016/j.jacbts.2016.03.003] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Atrial fibrillation (AF) usually starts as paroxysmal but can evolve relentlessly to the persistent and permanent forms. However, the mechanisms governing such a transition are unknown. The authors show that intracardiac serum levels of galectin (Gal)-3 are greater in patients with persistent than paroxysmal AF and that Gal-3 independently predicts atrial tachyarrhythmia recurrences after a single ablation procedure. Using a sheep model of persistent AF the authors further demonstrate that upstream therapy targeting Gal-3 diminishes both electrical remodeling and fibrosis by impairing transforming growth factor beta–mediated signaling and reducing myofibroblast activation. Accordingly, Gal-3 inhibition therapy increases the probability of AF termination and reduces the overall burden of AF. Therefore the authors postulate that Gal-3 inhibition is a potential new upstream therapy to prevent AF progression. Intracardiac serum galectin (Gal)-3 levels are shown to be greater in patients with persistent than paroxysmal atrial fibrillation (AF), and the Gal-3 level was an independent predictor of AF recurrences after a single ablation procedure. In a sheep model, the Gal-3 inhibitor GM-CT-01 (GMCT) reduced atrial fibroblast proliferation in vitro. GMCT mitigated atrial dilation, myocyte hypertrophy, fibrosis, and the expected increase in DF during transition to persistent AF. GMCT-treated sheep hearts had longer action potential durations, and fewer rotors and wavebreaks during AF than control. GMCT increased the number of spontaneous AF terminations and reduced overall AF burden.
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Affiliation(s)
- Yoshio Takemoto
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Rafael J Ramirez
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Miki Yokokawa
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Kuljeet Kaur
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Daniela Ponce-Balbuena
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Mohamad C Sinno
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - B Cicero Willis
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Hamid Ghanbari
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Steven R Ennis
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Guadalupe Guerrero-Serna
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Bettina C Henzi
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Rakesh Latchamsetty
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Roberto Ramos-Mondragon
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Hassan Musa
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Raphael P Martins
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Sandeep V Pandit
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Sami F Noujaim
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA
| | - Thomas Crawford
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Krit Jongnarangsin
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Frank Pelosi
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Frank Bogun
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Aman Chugh
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Omer Berenfeld
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
| | - Fred Morady
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - Hakan Oral
- Division of Cardiovascular Medicine, Cardiac Arrhythmia Service, University of Michigan, Ann Arbor, MI
| | - José Jalife
- Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI
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8
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Picones A, Loza-Huerta A, Segura-Chama P, Lara-Figueroa CO. Contribution of Automated Technologies to Ion Channel Drug Discovery. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2016; 104:357-378. [DOI: 10.1016/bs.apcsb.2016.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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9
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Yu HB, Zou BY, Wang XL, Li M. Investigation of miscellaneous hERG inhibition in large diverse compound collection using automated patch-clamp assay. Acta Pharmacol Sin 2016; 37:111-23. [PMID: 26725739 DOI: 10.1038/aps.2015.143] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 12/09/2015] [Indexed: 01/22/2023]
Abstract
AIM hERG potassium channels display miscellaneous interactions with diverse chemical scaffolds. In this study we assessed the hERG inhibition in a large compound library of diverse chemical entities and provided data for better understanding of the mechanisms underlying promiscuity of hERG inhibition. METHODS Approximately 300 000 compounds contained in Molecular Library Small Molecular Repository (MLSMR) library were tested. Compound profiling was conducted on hERG-CHO cells using the automated patch-clamp platform-IonWorks Quattro(™). RESULTS The compound library was tested at 1 and 10 μmol/L. IC50 values were predicted using a modified 4-parameter logistic model. Inhibitor hits were binned into three groups based on their potency: high (IC50<1 μmol/L), intermediate (1 μmol/L< IC50<10 μmol/L), and low (IC50>10 μmol/L) with hit rates of 1.64%, 9.17% and 16.63%, respectively. Six physiochemical properties of each compound were acquired and calculated using ACD software to evaluate the correlation between hERG inhibition and the properties: hERG inhibition was positively correlative to the physiochemical properties ALogP, molecular weight and RTB, and negatively correlative to TPSA. CONCLUSION Based on a large diverse compound collection, this study provides experimental evidence to understand the promiscuity of hERG inhibition. This study further demonstrates that hERG liability compounds tend to be more hydrophobic, high-molecular, flexible and polarizable.
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10
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Du Y, Days E, Romaine I, Abney KK, Kaufmann K, Sulikowski G, Stauffer S, Lindsley CW, Weaver CD. Development and validation of a thallium flux-based functional assay for the sodium channel NaV1.7 and its utility for lead discovery and compound profiling. ACS Chem Neurosci 2015; 6:871-8. [PMID: 25879403 DOI: 10.1021/acschemneuro.5b00004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Ion channels are critical for life, and they are targets of numerous drugs. The sequencing of the human genome has revealed the existence of hundreds of different ion channel subunits capable of forming thousands of ion channels. In the face of this diversity, we only have a few selective small-molecule tools to aid in our understanding of the role specific ion channels in physiology which may in turn help illuminate their therapeutic potential. Although the advent of automated electrophysiology has increased the rate at which we can screen for and characterize ion channel modulators, the technique's high per-measurement cost and moderate throughput compared to other high-throughput screening approaches limit its utility for large-scale high-throughput screening. Therefore, lower cost, more rapid techniques are needed. While ion channel types capable of fluxing calcium are well-served by low cost, very high-throughput fluorescence-based assays, other channel types such as sodium channels remain underserved by present functional assay techniques. In order to address this shortcoming, we have developed a thallium flux-based assay for sodium channels using the NaV1.7 channel as a model target. We show that the assay is able to rapidly and cost-effectively identify NaV1.7 inhibitors thus providing a new method useful for the discovery and profiling of sodium channel modulators.
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Affiliation(s)
| | | | | | - Kris K. Abney
- Meharry Medical
College Program in Pharmacology, Nashville, Tennessee 37208, United States
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11
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Abstract
INTRODUCTION Cardiac K(+) channels play a critical role in maintaining the normal electrical activity of the heart by setting the cell resting membrane potential and by determining the shape and duration of the action potential. Drugs that block the rapid (IKr) and slow (IKs) components of the delayed rectifier K(+) current have been widely used as class III antiarrhythmic agents. In addition, drugs that selectively target the ultra-rapid delayed rectifier current (IKur) and the acetylcholine-gated inward rectifier current (IKAch) have shown efficacy in the treatment of patients with atrial fibrillation. In order to meet the future demand for new antiarrhythmic agents, novel approaches for cardiac K(+) channel drug discovery will need to be developed. Further, K(+) channel screening assays utilizing primary and stem cell-derived cardiomyocytes will be essential for evaluating the cardiotoxicity of potential drug candidates. AREAS COVERED In this review, the author provides a brief background on the structure, function and pharmacology of cardiac voltage-gated and inward rectifier K(+) channels. He then focuses on describing and evaluating current technologies, such as ion flux and membrane potential-sensitive dye assays, used for cardiac K(+) channel drug discovery. EXPERT OPINION Cardiac K(+) channels will continue to represent significant clinical targets for drug discovery. Although fluorescent high-throughput screening (HTS) assays and automated patch clamp systems will remain the workhorse technologies for identifying lead compounds, innovations in the areas of microfluidics, micropatterning and biosensor fabrication will allow further growth of technologies using primary and stem cell-derived cardiomyocytes.
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Affiliation(s)
- Kenneth B Walsh
- University of South Carolina, School of Medicine, Department of Pharmacology, Physiology and Neuroscience , Columbia, SC 29209 , USA +1 803 216 3519 ; +1 803 216 3538 ;
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12
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He S, Lai Z, Ye Z, Dobbelaar P, Shah SK, Truong Q, Du W, Guo L, Liu J, Jian T, Qi H, Bakshi R, Hong Q, Dellureficio J, Reibarkh M, Samuel K, Reddy V, Mitelman S, Tong SX, Chicchi GG, Tsao KL, Trusca D, Wu M, Shao Q, Trujillo M, Fernandez G, Nelson D, Bunting P, Kerr J, Fitzgerald P, Morissette P, Volksdorf S, Eiermann GJ, Li C, Zhang B, Howard A, Zhou YP, Nargund RP, Hagmann WK. Investigation of Cardiovascular Effects of Tetrahydro-β-carboline sstr3 antagonists. ACS Med Chem Lett 2014; 5:748-53. [PMID: 25050159 PMCID: PMC4094257 DOI: 10.1021/ml500028c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 04/21/2014] [Indexed: 11/30/2022] Open
Abstract
Antagonism of somatostatin subtype receptor 3 (sstr3) has emerged as a potential treatment of Type 2 diabetes. Unfortunately, the development of our first preclinical candidate, MK-4256, was discontinued due to a dose-dependent QTc (QT interval corrected for heart rate) prolongation observed in a conscious cardiovascular (CV) dog model. As the fate of the entire program rested on resolving this issue, it was imperative to determine whether the observed QTc prolongation was associated with hERG channel (the protein encoded by the human Ether-à-go-go-Related Gene) binding or was mechanism-based as a result of antagonizing sstr3. We investigated a structural series containing carboxylic acids to reduce the putative hERG off-target activity. A key tool compound, 3A, was identified from this SAR effort. As a potent sstr3 antagonist, 3A was shown to reduce glucose excursion in a mouse oGTT assay. Consistent with its minimal hERG activity from in vitro assays, 3A elicited little to no effect in an anesthetized, vagus-intact CV dog model at high plasma drug levels. These results afforded the critical conclusion that sstr3 antagonism is not responsible for the QTc effects and therefore cleared a path for the program to progress.
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Affiliation(s)
- Shuwen He
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Zhong Lai
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Zhixiong Ye
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Peter
H. Dobbelaar
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Shrenik K. Shah
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Quang Truong
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Wu Du
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Liangqin Guo
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Jian Liu
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Tianying Jian
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Hongbo Qi
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Raman
K. Bakshi
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Qingmei Hong
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - James Dellureficio
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Mikhail Reibarkh
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Koppara Samuel
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Vijay
B. Reddy
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Stan Mitelman
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Sharon X. Tong
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Gary G. Chicchi
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Kwei-Lan Tsao
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Dorina Trusca
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Margaret Wu
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Qing Shao
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Maria
E. Trujillo
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Guillermo Fernandez
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Donald Nelson
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Patricia Bunting
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Janet Kerr
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Patrick Fitzgerald
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Pierre Morissette
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Sylvia Volksdorf
- Department
of Safety Assessment, 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - George J. Eiermann
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Cai Li
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Bei Zhang
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Andrew
D. Howard
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Yun-Ping Zhou
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Ravi P. Nargund
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - William K. Hagmann
- Merck Research Laboratories, Departments of Medicinal
Chemistry, Drug Metabolism and Pharmacokinetics, and Diabetes Research, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
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13
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Heijman J, Voigt N, Carlsson LG, Dobrev D. Cardiac safety assays. Curr Opin Pharmacol 2014; 15:16-21. [DOI: 10.1016/j.coph.2013.11.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 11/04/2013] [Accepted: 11/07/2013] [Indexed: 12/22/2022]
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14
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Thiophene carboxamide inhibitors of JAK2 as potential treatments for myleoproliferative neoplasms. Bioorg Med Chem Lett 2014; 24:1968-73. [DOI: 10.1016/j.bmcl.2014.02.064] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 02/20/2014] [Accepted: 02/24/2014] [Indexed: 01/30/2023]
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15
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Garcia ML, Priest BT, Alonso-Galicia M, Zhou X, Felix JP, Brochu RM, Bailey T, Thomas-Fowlkes B, Liu J, Swensen A, Pai LY, Xiao J, Hernandez M, Hoagland K, Owens K, Tang H, de Jesus RK, Roy S, Kaczorowski GJ, Pasternak A. Pharmacologic inhibition of the renal outer medullary potassium channel causes diuresis and natriuresis in the absence of kaliuresis. J Pharmacol Exp Ther 2014; 348:153-64. [PMID: 24142912 DOI: 10.1124/jpet.113.208603] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The renal outer medullary potassium (ROMK) channel, which is located at the apical membrane of epithelial cells lining the thick ascending loop of Henle and cortical collecting duct, plays an important role in kidney physiology by regulating salt reabsorption. Loss-of-function mutations in the human ROMK channel are associated with antenatal type II Bartter's syndrome, an autosomal recessive life-threatening salt-wasting disorder with mild hypokalemia. Similar observations have been reported from studies with ROMK knockout mice and rats. It is noteworthy that heterozygous carriers of Kir1.1 mutations associated with antenatal Bartter's syndrome have reduced blood pressure and a decreased risk of developing hypertension by age 60. Although selective ROMK inhibitors would be expected to represent a new class of diuretics, this hypothesis has not been pharmacologically tested. Compound A [5-(2-(4-(2-(4-(1H-tetrazol-1-yl)phenyl)acetyl)piperazin-1-yl)ethyl)isobenzofuran-1(3H)-one)], a potent ROMK inhibitor with appropriate selectivity and characteristics for in vivo testing, has been identified. Compound A accesses the channel through the cytoplasmic side and binds to residues lining the pore within the transmembrane region below the selectivity filter. In normotensive rats and dogs, short-term oral administration of compound A caused concentration-dependent diuresis and natriuresis that were comparable to hydrochlorothiazide. Unlike hydrochlorothiazide, however, compound A did not cause any significant urinary potassium losses or changes in plasma electrolyte levels. These data indicate that pharmacologic inhibition of ROMK has the potential for affording diuretic/natriuretic efficacy similar to that of clinically used diuretics but without the dose-limiting hypokalemia associated with the use of loop and thiazide-like diuretics.
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Affiliation(s)
- Maria L Garcia
- Departments of Ion Channels (M.L.G., B.T.P., J.P.F., R.M.B., T.B., B.T.-F., J.L., A.S., G.J.K.), Hypertension (M.A.-G., X.Z., L.-Y.P., J.X., M.H., S.R.), Drug Metabolism (K.O.), and Medicinal Chemistry (H.T., R. K.J., A.P.), Merck Research Laboratories, Rahway, New Jersey; and Safety and Exploratory Pharmacology, Merck Research Laboratories, West Point, Pennsylvania (K.H.)
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16
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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: 1.0] [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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17
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Portonovo SA, Salazar CS, Schmidt JJ. hERG drug response measured in droplet bilayers. Biomed Microdevices 2013; 15:255-9. [PMID: 23160842 DOI: 10.1007/s10544-012-9725-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We show measurements of the human cardiac potassium ion channel Kv11.1 (hERG) in droplet bilayers incorporated directly from commercial membrane preparations of HEK293 cells. Although we do not obtain ensemble conductance kinetics and rectification observed in patch clamp measurements of hERG, ensemble currents measured in our system showed inhibition dependent on astemizole and E-4031 concentration, with IC50 values similar to those found with patch clamp. The availability of engineered HEK cells expressing a variety of ion channels, combined with the simplicity of the inhibition measurement, suggest that droplet bilayers may have considerable technological potential for determination of ion channel drug potency.
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Affiliation(s)
- Shiva A Portonovo
- Department of Bioengineering, University of California, Los Angeles, 5121 Engineering V, 420 Westwood Plaza, Los Angeles, CA 90095, USA
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18
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Affiliation(s)
- Jens-Uwe Peters
- F. Hoffmann-La Roche Ltd., pRED, Pharma Research and Early Development, Discovery
Chemistry,
CH-4070 Basel, Switzerland
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19
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Carmosino M, Rizzo F, Torretta S, Procino G, Svelto M. High-throughput fluorescent-based NKCC functional assay in adherent epithelial cells. BMC Cell Biol 2013; 14:16. [PMID: 23506056 PMCID: PMC3618206 DOI: 10.1186/1471-2121-14-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 02/28/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The kidney-specific NKCC cotransporter isoform NKCC2 is involved in the Na(+) reabsorption in the Thich Ascending Limb (TAL) cells and in the regulation of body fluid volume. In contrast, the isoform NKCC1 represents the major pathway for Cl- entry in endothelial cells, playing a crucial role in cell volume regulation and vascular tone. Importantly, both NKCC isoforms are involved in the regulation of blood pressure and represent important potential drug targets for the treatment of hypertension. RESULTS Taking advantage of an existing Thallium (Tl(+))-based kit, we set up a Tl(+) influx-based fluorescent assay, that can accurately and rapidly measure NKCC transporter activity in adherent epithelial cells using the high-throughput Flex station device. We assessed the feasibility of this assay in the renal epithelial LLC-PK1 cells stably transfected with a previously characterized chimeric NKCC2 construct (c-NKCC2). We demonstrated that the assay is highly reproducible, offers high temporal resolution of NKCC-mediated ion flux profiles and, importantly, being a continuous assay, it offers improved sensitivity over previous endpoint NKCC functional assays. CONCLUSIONS So far the screening of NKCC transporters activity has been done by (86)Rb(+) influx assays. Indeed, a fluorescence-based high-throughput screening method for testing NKCC inhibitors would be extremely useful in the development and characterization of new anti-hypertensive drugs.
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Affiliation(s)
- Monica Carmosino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Amendola 165/A, Bari, 70126, Italy
- Department of Sciences, University of Basilicata, Via dell’Ateneo Lucano, Potenza, 85100, Italy
| | - Federica Rizzo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Amendola 165/A, Bari, 70126, Italy
| | - Silvia Torretta
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Amendola 165/A, Bari, 70126, Italy
| | - Giuseppe Procino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Amendola 165/A, Bari, 70126, Italy
| | - Maria Svelto
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Amendola 165/A, Bari, 70126, Italy
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20
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Klein MT, Vinson PN, Niswender CM. Approaches for probing allosteric interactions at 7 transmembrane spanning receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 115:1-59. [PMID: 23415091 PMCID: PMC5482179 DOI: 10.1016/b978-0-12-394587-7.00001-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In recent years, allosteric modulation of 7 transmembrane spanning receptors (7TMRs) has become a highly productive and exciting field of receptor pharmacology and drug discovery efforts. Positive and negative allosteric modulators (PAMs and NAMs, respectively) present a number of pharmacological and therapeutic advantages over conventional orthosteric ligands, including improved receptor-subtype selectivity, a lower propensity to induce receptor desensitization, the preservation of endogenous temporal and spatial activation of receptors, greater chemical flexibility for optimization of drug metabolism and pharmacokinetic parameters, and saturability of effect at target receptors, thus improving safety concerns and risk of overdose. Additionally, the relatively new concept of allosteric modulator-mediated receptor signal bias opens up a number of intriguing possibilities for PAMs, NAMs, and allosteric agonists, including the potential to selectively activate therapeutically beneficial signaling cascades, which could yield a superior tissue selectivity and side effect profile of allosteric modulators. However, there are a number of considerations and caveats that must be addressed when screening for and characterizing the properties of 7TMR allosteric modulators. Mode of pharmacology, methodology used to monitor receptor activity, detection of appropriate downstream analytes, selection of orthosteric probe, and assay time-course must all be considered when implementing any high-throughput screening campaign or when characterizing the properties of active compounds. Yet compared to conventional agonist/antagonist drug discovery programs, these elements of assay design are often a great deal more complicated when working with 7TMRs allosteric modulators. Moreover, for classical pharmacological methodologies and analyses, like radioligand binding and the assessment of compound affinity, the properties of allosteric modulators yield data that are more nuanced than orthosteric ligand-receptor interactions. In this review, we discuss the current methodologies being used to identify and characterize allosteric modulators, lending insight into the approaches that have been most successful in accurately and robustly identifying hit compounds. New label-free technologies capable of detecting phenotypic cellular changes in response to receptor activation are powerful tools well suited for assessing subtle or potentially masked cellular responses to allosteric modulation of 7TMRs. Allosteric modulator-induced receptor signal bias and the assay systems available to probe the various downstream signaling outcomes of receptor activation are also discussed.
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Affiliation(s)
- Michael T Klein
- Department of Pharmacology, Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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21
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Shao PP, Ye F, Chakravarty PK, Varughese DJ, Herrington JB, Dai G, Bugianesi RM, Haedo RJ, Swensen AM, Warren VA, Smith MM, Garcia ML, McManus OB, Lyons KA, Li X, Green M, Jochnowitz N, McGowan E, Mistry S, Sun SY, Abbadie C, Kaczorowski GJ, Duffy JL. Aminopiperidine Sulfonamide Cav2.2 Channel Inhibitors for the Treatment of Chronic Pain. J Med Chem 2012; 55:9847-55. [DOI: 10.1021/jm301056k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pengcheng P. Shao
- Departments of Medicinal Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - Feng Ye
- Departments of Medicinal Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - Prasun K. Chakravarty
- Departments of Medicinal Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - Deepu J. Varughese
- Departments of Medicinal Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - James B. Herrington
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Ge Dai
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Randal M. Bugianesi
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Rodolfo J. Haedo
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Andrew M. Swensen
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Vivien A. Warren
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - McHardy M. Smith
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Maria L. Garcia
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Owen B. McManus
- Ion Channels, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Kathryn A. Lyons
- Drug Metabolism and
Pharmacokinetics, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - Xiaohua Li
- Drug Metabolism and
Pharmacokinetics, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - Mitchell Green
- Drug Metabolism and
Pharmacokinetics, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
| | - Nina Jochnowitz
- Pharmacology, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Erin McGowan
- Pharmacology, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Shruti Mistry
- Pharmacology, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Shu-Yu Sun
- Pharmacology, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | - Catherine Abbadie
- Pharmacology, Merck Research Laboratories, Rahway, New Jersey 07065, United
States
| | | | - Joseph L. Duffy
- Departments of Medicinal Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065,
United States
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22
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Abstract
Lipid bilayers are natural barriers of biological cells and cellular compartments. Membrane proteins integrated in biological membranes enable vital cell functions such as signal transduction and the transport of ions or small molecules. In order to determine the activity of a protein of interest at defined conditions, the membrane protein has to be integrated into artificial lipid bilayers immobilized on a surface. For the fabrication of such biosensors expertise is required in material science, surface and analytical chemistry, molecular biology and biotechnology. Specifically, techniques are needed for structuring surfaces in the micro- and nanometer scale, chemical modification and analysis, lipid bilayer formation, protein expression, purification and solubilization, and most importantly, protein integration into engineered lipid bilayers. Electrochemical and optical methods are suitable to detect membrane activity-related signals. The importance of structural knowledge to understand membrane protein function is obvious. Presently only a few structures of membrane proteins are solved at atomic resolution. Functional assays together with known structures of individual membrane proteins will contribute to a better understanding of vital biological processes occurring at biological membranes. Such assays will be utilized in the discovery of drugs, since membrane proteins are major drug targets.
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23
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Potet F, Lorinc AN, Chaigne S, Hopkins CR, Venkataraman R, Stepanovic SZ, Lewis LM, Days E, Sidorov VY, Engers DW, Zou B, Afshartous D, George AL, Campbell CM, Balser JR, Li M, Baudenbacher FJ, Lindsley CW, Weaver CD, Kupershmidt S. Identification and characterization of a compound that protects cardiac tissue from human Ether-à-go-go-related gene (hERG)-related drug-induced arrhythmias. J Biol Chem 2012; 287:39613-25. [PMID: 23033485 DOI: 10.1074/jbc.m112.380162] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The human Ether-à-go-go-related gene (hERG)-encoded K(+) current, I(Kr) is essential for cardiac repolarization but is also a source of cardiotoxicity because unintended hERG inhibition by diverse pharmaceuticals can cause arrhythmias and sudden cardiac death. We hypothesized that a small molecule that diminishes I(Kr) block by a known hERG antagonist would constitute a first step toward preventing hERG-related arrhythmias and facilitating drug discovery. Using a high-throughput assay, we screened a library of compounds for agents that increase the IC(70) of dofetilide, a well characterized hERG blocker. One compound, VU0405601, with the desired activity was further characterized. In isolated, Langendorff-perfused rabbit hearts, optical mapping revealed that dofetilide-induced arrhythmias were reduced after pretreatment with VU0405601. Patch clamp analysis in stable hERG-HEK cells showed effects on current amplitude, inactivation, and deactivation. VU0405601 increased the IC(50) of dofetilide from 38.7 to 76.3 nM. VU0405601 mitigates the effects of hERG blockers from the extracellular aspect primarily by reducing inactivation, whereas most clinically relevant hERG inhibitors act at an inner pore site. Structure-activity relationships surrounding VU0405601 identified a 3-pyridiyl and a naphthyridine ring system as key structural components important for preventing hERG inhibition by multiple inhibitors. These findings indicate that small molecules can be designed to reduce the sensitivity of hERG to inhibitors.
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Affiliation(s)
- Franck Potet
- Department of Anesthesiology, Vanderbilt University, Nashville, Tennessee 37232, USA
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24
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hERG ion channel pharmacology: cell membrane liposomes in porous-supported lipid bilayers compared with whole-cell patch-clamping. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2012; 41:949-58. [PMID: 22936309 DOI: 10.1007/s00249-012-0852-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 08/02/2012] [Accepted: 08/17/2012] [Indexed: 10/28/2022]
Abstract
The purpose of this study was to obtain functional hERG ion channel protein for use in a non-cell-based ion channel assay. hERG was expressed in Sf9 insect cells. Attempts to solubilise the hERG protein from Sf9 insect cell membranes using non-ionic detergents (NP40 and DDM) were not successful. We therefore generated liposomes from the unpurified membrane fraction and incorporated these into porous Teflon-supported bilayer lipid membranes. Macroscopic potassium currents (1 nA) were recorded that approximated those in whole-cell patch-clamping, but the channels were bidirectional in the bilayer lipid membrane (BLM). Currents were partially inhibited by the hERG blockers E4031, verapamil, and clofilium, indicating that the protein of interest is present at high levels in the BLM relative to endogenous channels. Cell liposomes produced from Sf9 insect cell membranes expressing voltage-gated sodium channels also gave current responses that were activated by veratridine and inhibited by saxitoxin. These results demonstrate that purification of the ion channel of interest is not always necessary for liposomes used in macro-current BLM systems.
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25
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Vandenberg JI, Perry MD, Perrin MJ, Mann SA, Ke Y, Hill AP. hERG K+ Channels: Structure, Function, and Clinical Significance. Physiol Rev 2012; 92:1393-478. [DOI: 10.1152/physrev.00036.2011] [Citation(s) in RCA: 526] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The human ether-a-go-go related gene (hERG) encodes the pore-forming subunit of the rapid component of the delayed rectifier K+ channel, Kv11.1, which are expressed in the heart, various brain regions, smooth muscle cells, endocrine cells, and a wide range of tumor cell lines. However, it is the role that Kv11.1 channels play in the heart that has been best characterized, for two main reasons. First, it is the gene product involved in chromosome 7-associated long QT syndrome (LQTS), an inherited disorder associated with a markedly increased risk of ventricular arrhythmias and sudden cardiac death. Second, blockade of Kv11.1, by a wide range of prescription medications, causes drug-induced QT prolongation with an increase in risk of sudden cardiac arrest. In the first part of this review, the properties of Kv11.1 channels, including biogenesis, trafficking, gating, and pharmacology are discussed, while the second part focuses on the pathophysiology of Kv11.1 channels.
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Affiliation(s)
- Jamie I. Vandenberg
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Matthew D. Perry
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Mark J. Perrin
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Stefan A. Mann
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Ying Ke
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Adam P. Hill
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
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26
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Tang H, Walsh SP, Yan Y, de Jesus RK, Shahripour A, Teumelsan N, Zhu Y, Ha S, Owens KA, Thomas-Fowlkes BS, Felix JP, Liu J, Kohler M, Priest BT, Bailey T, Brochu R, Alonso-Galicia M, Kaczorowski GJ, Roy S, Yang L, Mills SG, Garcia ML, Pasternak A. Discovery of Selective Small Molecule ROMK Inhibitors as Potential New Mechanism Diuretics. ACS Med Chem Lett 2012; 3:367-72. [PMID: 24900480 DOI: 10.1021/ml3000066] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 03/28/2012] [Indexed: 11/28/2022] Open
Abstract
The renal outer medullary potassium channel (ROMK or Kir1.1) is a putative drug target for a novel class of diuretics that could be used for the treatment of hypertension and edematous states such as heart failure. An internal high-throughput screening campaign identified 1,4-bis(4-nitrophenethyl)piperazine (5) as a potent ROMK inhibitor. It is worth noting that this compound was identified as a minor impurity in a screening hit that was responsible for all of the initially observed ROMK activity. Structure-activity studies resulted in analogues with improved rat pharmacokinetic properties and selectivity over the hERG channel, providing tool compounds that can be used for in vivo pharmacological assessment. The featured ROMK inhibitors were also selective against other members of the inward rectifier family of potassium channels.
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Affiliation(s)
- Haifeng Tang
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Shawn P. Walsh
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Yan Yan
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Reynalda K. de Jesus
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Aurash Shahripour
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Nardos Teumelsan
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Yuping Zhu
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Sookhee Ha
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Karen A. Owens
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Brande S. Thomas-Fowlkes
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - John P. Felix
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Jessica Liu
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Martin Kohler
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Birgit T. Priest
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Timothy Bailey
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Richard Brochu
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Magdalena Alonso-Galicia
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Gregory J. Kaczorowski
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Sophie Roy
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Lihu Yang
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Sander G. Mills
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Maria L. Garcia
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
| | - Alexander Pasternak
- Departments of †Medicinal Chemistry, ‡Hypertension, §Ion Channels, ⊥Preclinical DMPK, and ¶Chemistry Modeling, Merck Research Laboratories, Rahway
New Jersey 07065,
United States
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27
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Ponte CG, McManus OB, Schmalhofer WA, Shen DM, Dai G, Stevenson A, Sur S, Shah T, Kiss L, Shu M, Doherty JB, Nargund R, Kaczorowski GJ, Suarez-Kurtz G, Garcia ML. Selective, direct activation of high-conductance, calcium-activated potassium channels causes smooth muscle relaxation. Mol Pharmacol 2012; 81:567-77. [PMID: 22241372 DOI: 10.1124/mol.111.075853] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
High-conductance calcium-activated potassium (Maxi-K) channels are present in smooth muscle where they regulate tone. Activation of Maxi-K channels causes smooth muscle hyperpolarization and shortening of action-potential duration, which would limit calcium entry through voltage-dependent calcium channels leading to relaxation. Although Maxi-K channels appear to indirectly mediate the relaxant effects of a number of agents, activators that bind directly to the channel with appropriate potency and pharmacological properties useful for proof-of-concept studies are not available. Most agents identified to date display significant polypharmacy that severely compromises interpretation of experimental data. In the present study, a high-throughput, functional, cell-based assay for identifying Maxi-K channel agonists was established and used to screen a large sample collection (>1.6 million compounds). On the basis of potency and selectivity, a family of tetrahydroquinolines was further characterized. Medicinal chemistry efforts afforded identification of compound X, from which its two enantiomers, Y and Z, were resolved. In in vitro assays, Z is more potent than Y as a channel activator. The same profile is observed in tissues where the ability of either agent to relax precontracted smooth muscles, via a potassium channel-dependent mechanism, is demonstrated. These data, taken together, suggest that direct activation of Maxi-K channels represents a mechanism to be explored for the potential treatment of a number of diseases associated with smooth muscle hyperexcitability.
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Affiliation(s)
- Cristiano G Ponte
- Department of Biotechnology, Instituto Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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28
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Electrophysiological study of V535M hERG mutation of LQT2. ACTA ACUST UNITED AC 2011; 31:741-748. [DOI: 10.1007/s11596-011-0670-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Indexed: 10/14/2022]
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29
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Kaczorowski GJ, Garcia ML, Bode J, Hess SD, Patel UA. The importance of being profiled: improving drug candidate safety and efficacy using ion channel profiling. Front Pharmacol 2011; 2:78. [PMID: 22171219 PMCID: PMC3236397 DOI: 10.3389/fphar.2011.00078] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 11/19/2011] [Indexed: 11/13/2022] Open
Abstract
Profiling of putative lead compounds against a representative panel of relevant enzymes, receptors, ion channels, and transporters is a pragmatic approach to establish a preliminary view of potential issues that might later hamper development. An early idea of which off-target activities must be minimized can save valuable time and money during the preclinical lead optimization phase if pivotal questions are asked beyond the usual profiling at hERG. The best data for critical evaluation of activity at ion channels is obtained using functional assays, since binding assays cannot detect all interactions and do not provide information on whether the interaction is that of an agonist, antagonist, or allosteric modulator. For ion channels present in human cardiac muscle, depending on the required throughput, manual-, or automated-patch-clamp methodologies can be easily used to evaluate compounds individually to accurately reveal any potential liabilities. The issue of expanding screening capacity against a cardiac panel has recently been addressed by developing a series of robust, high-throughput, cell-based counter-screening assays employing fluorescence-based readouts. Similar assay development approaches can be used to configure panels of efficacy assays that can be used to assess selectivity within a family of related ion channels, such as Nav1.X channels. This overview discusses the benefits of in vitro assays, specific decision points where profiling can be of immediate benefit, and highlights the development and validation of patch-clamp and fluorescence-based profiling assays for ion channels (for examples of fluorescence-based assays, see Bhave et al., 2010; and for high-throughput patch-clamp assays see Mathes, 2006; Schrøder et al., 2008).
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Fujii M, Ohya S, Yamamura H, Imaizumi Y. [Screening methods for ion-channels drug discovery and new ideas]. Nihon Yakurigaku Zasshi 2011; 138:229-233. [PMID: 22156258 DOI: 10.1254/fpj.138.229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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Raphemot R, Lonergan DF, Nguyen TT, Utley T, Lewis LM, Kadakia R, Weaver CD, Gogliotti R, Hopkins C, Lindsley CW, Denton JS. Discovery, characterization, and structure-activity relationships of an inhibitor of inward rectifier potassium (Kir) channels with preference for Kir2.3, Kir3.x, and Kir7.1. Front Pharmacol 2011; 2:75. [PMID: 22275899 PMCID: PMC3254186 DOI: 10.3389/fphar.2011.00075] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 11/07/2011] [Indexed: 12/03/2022] Open
Abstract
The inward rectifier family of potassium (Kir) channels is comprised of at least 16 family members exhibiting broad and often overlapping cellular, tissue, or organ distributions. The discovery of disease-causing mutations in humans and experiments on knockout mice has underscored the importance of Kir channels in physiology and in some cases raised questions about their potential as drug targets. However, the paucity of potent and selective small-molecule modulators targeting specific family members has with few exceptions mired efforts to understand their physiology and assess their therapeutic potential. A growing body of evidence suggests that G protein-coupled inward rectifier K (GIRK) channels of the Kir3.X subfamily may represent novel targets for the treatment of atrial fibrillation. In an effort to expand the molecular pharmacology of GIRK, we performed a thallium (Tl(+)) flux-based high-throughput screen of a Kir1.1 inhibitor library for modulators of GIRK. One compound, termed VU573, exhibited 10-fold selectivity for GIRK over Kir1.1 (IC(50) = 1.9 and 19 μM, respectively) and was therefore selected for further study. In electrophysiological experiments performed on Xenopus laevis oocytes and mammalian cells, VU573 inhibited Kir3.1/3.2 (neuronal GIRK) and Kir3.1/3.4 (cardiac GIRK) channels with equal potency and preferentially inhibited GIRK, Kir2.3, and Kir7.1 over Kir1.1 and Kir2.1.Tl(+) flux assays were established for Kir2.3 and the M125R pore mutant of Kir7.1 to support medicinal chemistry efforts to develop more potent and selective analogs for these channels. The structure-activity relationships of VU573 revealed few analogs with improved potency, however two compounds retained most of their activity toward GIRK and Kir2.3 and lost activity toward Kir7.1. We anticipate that the VU573 series will be useful for exploring the physiology and structure-function relationships of these Kir channels.
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Affiliation(s)
- Rene Raphemot
- Department of Anesthesiology, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
| | - Daniel F. Lonergan
- Department of Anesthesiology, Vanderbilt University School of MedicineNashville, TN, USA
| | - Thuy T. Nguyen
- Department of Anesthesiology, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
| | - Thomas Utley
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
| | - L. Michelle Lewis
- Vanderbilt Institute of Chemical Biology, Vanderbilt UniversityNashville, TN, USA
| | - Rishin Kadakia
- Department of Anesthesiology, Vanderbilt University School of MedicineNashville, TN, USA
| | - C. David Weaver
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Vanderbilt Institute of Chemical Biology, Vanderbilt UniversityNashville, TN, USA
| | - Rocco Gogliotti
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of MedicineNashville, TN, USA
| | - Corey Hopkins
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Vanderbilt Institute of Chemical Biology, Vanderbilt UniversityNashville, TN, USA
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Chemistry, Vanderbilt UniversityNashville, TN, USA
- Vanderbilt Specialized Chemistry Center for Accelerated Probe Development, Molecular Libraries Probe Production Centers NetworkNashville, TN, USA
| | - Craig W. Lindsley
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Vanderbilt Institute of Chemical Biology, Vanderbilt UniversityNashville, TN, USA
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Chemistry, Vanderbilt UniversityNashville, TN, USA
- Vanderbilt Specialized Chemistry Center for Accelerated Probe Development, Molecular Libraries Probe Production Centers NetworkNashville, TN, USA
| | - Jerod S. Denton
- Department of Anesthesiology, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Vanderbilt Institute of Chemical Biology, Vanderbilt UniversityNashville, TN, USA
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