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Pitsillou E, Logothetis ANO, Liang JJ, El-Osta A, Hung A, AbuMaziad AS, Karagiannis TC. Identification of Potential Modulators of a Pathogenic G Protein-Gated Inwardly Rectifying K + Channel 4 Mutant: In Silico Investigation in the Context of Drug Discovery for Hypertension. Molecules 2023; 28:7946. [PMID: 38138436 PMCID: PMC10745636 DOI: 10.3390/molecules28247946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 11/24/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
Genetic abnormalities have been associated with primary aldosteronism, a major cause of secondary hypertension. This includes mutations in the KCNJ5 gene, which encodes G protein-gated inwardly rectifying K+ channel 4 (GIRK4). For example, the substitution of glycine with glutamic acid gives rise to the pathogenic GIRK4G151E mutation, which alters channel selectivity, making it more permeable to Na+ and Ca2+. While tertiapin and tertiapin-Q are well-known peptide inhibitors of the GIRK4WT channel, clinically, there is a need for the development of selective modulators of mutated channels, including GIRK4G151E. Using in silico methods, including homology modeling, protein-peptide docking, ligand-binding site prediction, and molecular docking, we aimed to explore potential modulators of GIRK4WT and GIRK4G151E. Firstly, protein-peptide docking was performed to characterize the binding site of tertiapin and its derivative to the GIRK4 channels. In accordance with previous studies, the peptide inhibitors preferentially bind to the GIRK4WT channel selectivity filter compared to GIRK4G151E. A ligand-binding site analysis was subsequently performed, resulting in the identification of two potential regions of interest: the central cavity and G-loop gate. Utilizing curated chemical libraries, we screened over 700 small molecules against the central cavity of the GIRK4 channels. Flavonoids, including luteolin-7-O-rutinoside and rutin, and the macrolides rapamycin and troleandomycin bound strongly to the GIRK4 channels. Similarly, xanthophylls, particularly luteoxanthin, bound to the central cavity with a strong preference towards the mutated GIRK4G151E channel compared to GIRK4WT. Overall, our findings suggest potential lead compounds for further investigation, particularly luteoxanthin, that may selectively modulate GIRK4 channels.
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Affiliation(s)
- Eleni Pitsillou
- Epigenomic Medicine Laboratory at prospED Polytechnic, Carlton, VIC 3053, Australia
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia
| | - Alexander N. O. Logothetis
- Epigenomic Medicine Laboratory at prospED Polytechnic, Carlton, VIC 3053, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Julia J. Liang
- Epigenomic Medicine Laboratory at prospED Polytechnic, Carlton, VIC 3053, Australia
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC 3004, Australia
| | - Assam El-Osta
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC 3004, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Sha Tin, Hong Kong SAR, China
- Hong Kong Institute of Diabetes and Obesity, Prince of Wales Hospital, The Chinese University of Hong Kong, 3/F Lui Che Woo Clinical Sciences Building, 30-32 Ngan Shing Street, Sha Tin, Hong Kong SAR, China
- Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Sha Tin, Hong Kong SAR, China
- Biomedical Laboratory Science, Department of Technology, Faculty of Health, University College Copenhagen, 1799 Copenhagen, Denmark
| | - Andrew Hung
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia
| | - Asmaa S. AbuMaziad
- Department of Pediatrics, College of Medicine Tucson, The University of Arizona, Tucson, AZ 85724, USA
| | - Tom C. Karagiannis
- Epigenomic Medicine Laboratory at prospED Polytechnic, Carlton, VIC 3053, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC 3010, Australia
- Epigenetics in Human Health and Disease Program, Baker Heart and Diabetes Institute, 75 Commercial Road, Prahran, VIC 3004, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC 3010, Australia
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2
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Anderson A, Vo BN, de Velasco EMF, Hopkins CR, Weaver CD, Wickman K. Characterization of VU0468554, a New Selective Inhibitor of Cardiac G Protein-Gated Inwardly Rectifying K + Channels. Mol Pharmacol 2021; 100:540-547. [PMID: 34503975 DOI: 10.1124/molpharm.121.000311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 09/01/2021] [Indexed: 11/22/2022] Open
Abstract
G protein-gated inwardly rectifying K+ (GIRK) channels are critical mediators of excitability in the heart and brain. Enhanced GIRK-channel activity has been implicated in the pathogenesis of supraventricular arrhythmias, including atrial fibrillation. The lack of selective pharmacological tools has impeded efforts to investigate the therapeutic potential of cardiac GIRK-channel interventions in arrhythmias. Here, we characterize a recently identified GIRK-channel inhibitor, VU0468554. Using whole-cell electrophysiological approaches and primary cultures of sinoatrial nodal cells and hippocampal neurons, we show that VU0468554 more effectively inhibits the cardiac GIRK channel than the neuronal GIRK channel. Concentration-response experiments suggest that VU0468554 inhibits Gβγ-activated GIRK channels in noncompetitive and potentially uncompetitive fashion. In contrast, VU0468554 competitively inhibits GIRK-channel activation by ML297, a GIRK-channel activator containing the same chemical scaffold as VU0468554. In the isolated heart model, VU0468554 partially reversed carbachol-induced bradycardia in hearts from wild-type mice but not Girk4-/- mice. Collectively, these data suggest that VU0468554 represents a promising new pharmacological tool for targeting cardiac GIRK channels with therapeutic implications for relevant cardiac arrhythmias. SIGNIFICANCE STATEMENT: Although cardiac GIRK-channel inhibition shows promise for the treatment of supraventricular arrhythmias, the absence of subtype-selective channel inhibitors has hindered exploration into this therapeutic strategy. This study utilizes whole-cell patch-clamp electrophysiology to characterize the new GIRK-channel inhibitor VU0468554 in human embryonic kidney 293T cells and primary cultures. We report that VU0468554 exhibits a favorable pharmacodynamic profile for cardiac over neuronal GIRK channels and partially reverses GIRK-mediated bradycardia in the isolated mouse heart model.
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Affiliation(s)
- Allison Anderson
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Baovi N Vo
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Ezequiel Marron Fernandez de Velasco
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Corey R Hopkins
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - C David Weaver
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Kevin Wickman
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
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3
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Sharma S, Lesiak L, Aretz CD, Du Y, Kumar S, Gautam N, Alnouti Y, Dhuria NV, Chhonker YS, Weaver CD, Hopkins CR. Discovery, synthesis and biological characterization of a series of N-(1-(1,1-dioxidotetrahydrothiophen-3-yl)-3-methyl-1 H-pyrazol-5-yl)acetamide ethers as novel GIRK1/2 potassium channel activators. RSC Med Chem 2021; 12:1366-1373. [PMID: 34458739 PMCID: PMC8372201 DOI: 10.1039/d1md00129a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/04/2021] [Indexed: 01/14/2023] Open
Abstract
The present study describes the discovery and characterization of a series of N-(1-(1,1-dioxidotetrahydrothiophen-3-yl)-3-methyl-1H-pyrazol-5-yl)acetamide ethers as G protein-gated inwardly-rectifying potassium (GIRK) channel activators. From our previous lead optimization efforts, we have identified a new ether-based scaffold and paired this with a novel sulfone-based head group to identify a potent and selective GIRK1/2 activator. In addition, we evaluated the compounds in tier 1 DMPK assays and have identified compounds that display nanomolar potency as GIRK1/2 activators with improved metabolic stability over the prototypical urea-based compounds.
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Affiliation(s)
- Swagat Sharma
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Lauren Lesiak
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Christopher D Aretz
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Yu Du
- Department of Pharmacology, Vanderbilt University School of Medicine Nashville TN 37232 USA
| | - Sushil Kumar
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Nagsen Gautam
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Yazen Alnouti
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Nikilesh V Dhuria
- Department of Pharmacy Practice and Science, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Yashpal S Chhonker
- Department of Pharmacy Practice and Science, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
| | - C David Weaver
- Department of Pharmacology, Vanderbilt University School of Medicine Nashville TN 37232 USA
| | - Corey R Hopkins
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center Omaha NE 68198 USA
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4
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Kir Channel Molecular Physiology, Pharmacology, and Therapeutic Implications. Handb Exp Pharmacol 2021; 267:277-356. [PMID: 34345939 DOI: 10.1007/164_2021_501] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
For the past two decades several scholarly reviews have appeared on the inwardly rectifying potassium (Kir) channels. We would like to highlight two efforts in particular, which have provided comprehensive reviews of the literature up to 2010 (Hibino et al., Physiol Rev 90(1):291-366, 2010; Stanfield et al., Rev Physiol Biochem Pharmacol 145:47-179, 2002). In the past decade, great insights into the 3-D atomic resolution structures of Kir channels have begun to provide the molecular basis for their functional properties. More recently, computational studies are beginning to close the time domain gap between in silico dynamic and patch-clamp functional studies. The pharmacology of these channels has also been expanding and the dynamic structural studies provide hope that we are heading toward successful structure-based drug design for this family of K+ channels. In the present review we focus on placing the physiology and pharmacology of this K+ channel family in the context of atomic resolution structures and in providing a glimpse of the promising future of therapeutic opportunities.
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Weaver CD, Denton JS. Next-generation inward rectifier potassium channel modulators: discovery and molecular pharmacology. Am J Physiol Cell Physiol 2021; 320:C1125-C1140. [PMID: 33826405 DOI: 10.1152/ajpcell.00548.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Inward rectifying potassium (Kir) channels play important roles in both excitable and nonexcitable cells of various organ systems and could represent valuable new drug targets for cardiovascular, metabolic, immune, and neurological diseases. In nonexcitable epithelial cells of the kidney tubule, for example, Kir1.1 (KCNJ1) and Kir4.1 (KCNJ10) are linked to sodium reabsorption in the thick ascending limb of Henle's loop and distal convoluted tubule, respectively, and have been explored as novel-mechanism diuretic targets for managing hypertension and edema. G protein-coupled Kir channels (Kir3) channels expressed in the central nervous system are critical effectors of numerous signal transduction pathways underlying analgesia, addiction, and respiratory-depressive effects of opioids. The historical dearth of pharmacological tool compounds for exploring the therapeutic potential of Kir channels has led to a molecular target-based approach using high-throughput screen (HTS) of small-molecule libraries and medicinal chemistry to develop "next-generation" Kir channel modulators that are both potent and specific for their targets. In this article, we review recent efforts focused specifically on discovery and improvement of target-selective molecular probes. The reader is introduced to fluorescence-based thallium flux assays that have enabled much of this work and then provided with an overview of progress made toward developing modulators of Kir1.1 (VU590, VU591), Kir2.x (ML133), Kir3.X (ML297, GAT1508, GiGA1, VU059331), Kir4.1 (VU0134992), and Kir7.1 (ML418). We discuss what is known about the small molecules' molecular mechanisms of action, in vitro and in vivo pharmacology, and then close with our view of what critical work remains to be done.
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Affiliation(s)
- C David Weaver
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee.,Department of Chemistry, Vanderbilt University, Nashville, Tennessee.,Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee
| | - Jerod S Denton
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee.,Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee.,Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee
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6
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Zhao Y, Gameiro-Ros I, Glaaser IW, Slesinger PA. Advances in Targeting GIRK Channels in Disease. Trends Pharmacol Sci 2021; 42:203-215. [PMID: 33468322 DOI: 10.1016/j.tips.2020.12.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/30/2020] [Accepted: 12/11/2020] [Indexed: 12/12/2022]
Abstract
G protein-gated inwardly rectifying potassium (GIRK) channels are essential regulators of cell excitability in the brain. While they are implicated in a variety of neurological diseases in both human and animal model studies, their therapeutic potential has been largely untapped. Here, we review recent advances in the development of small molecule compounds that specifically modulate GIRK channels and compare them with first-generation compounds that exhibit off-target activity. We describe the method of discovery of these small molecule modulators, their chemical features, and their effects in vivo. These studies provide a promising outlook on the future development of subunit-specific GIRK modulators to regulate neuronal excitability in a brain region-specific manner.
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Affiliation(s)
- Yulin Zhao
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Isabel Gameiro-Ros
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ian W Glaaser
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paul A Slesinger
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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7
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Abney KK, Bubser M, Du Y, Kozek KA, Bridges TM, Lindsley CW, Daniels JS, Morrison RD, Wickman K, Hopkins CR, Jones CK, Weaver CD. Analgesic Effects of the GIRK Activator, VU0466551, Alone and in Combination with Morphine in Acute and Persistent Pain Models. ACS Chem Neurosci 2019; 10:1294-1299. [PMID: 30474955 DOI: 10.1021/acschemneuro.8b00370] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
G protein-gated inwardly rectifying potassium (GIRK) channels are potassium-selective ion channels. As their name suggests, GIRK channels are effectors of Gi/o G protein-couple receptors whereby activation of these GPCRs leads to increased GIRK channel activity resulting in decreased cellular excitability. In this way, GIRK channels play diverse roles in physiology as effectors of Gi/o-coupled GPCRs: peacemaking in the heart rate, modulation of hormone secretion in endocrine tissues, as well as numerous CNS functions including learning, memory, and addiction/reward. Notably, GIRK channels are widely expressed along the spinothalamic tract and are positioned to play roles in both ascending and descending pain pathways. More notably, GIRK channel knockout and knock-down studies have found that GIRK channels play a major role in the action of opioid analgesics which act predominantly through Gi/o-coupled, opioid-activated GPCRs (e.g., μ-opioid receptors). Recent advances in GIRK channel pharmacology have led to the development of small molecules that directly and selectively activate GIRK channels. Based on research implicating the involvement of GIRK channels in pain pathways and as effectors of opioid analgesics, we conducted a study to determine whether direct pharmacological activation of GIRK channels could produce analgesic efficacy and/or augment the analgesic efficacy morphine, an opioid receptor agonist capable of activating μ-opioid receptors as well as other opioid receptor subtypes. In the present study, we demonstrate that the small-molecule GIRK activator, VU0466551, has analgesic effects when dosed alone or in combination with submaximally effective doses of morphine.
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Affiliation(s)
- Kristopher K. Abney
- School of Graduate Studies and Research, Meharry Medical College, Nashville, Tennessee 37208, United States
| | - Michael Bubser
- Vanderbilt Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Nashville, Tennessee 37232, United States
| | - Yu Du
- Vanderbilt Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Krystian A. Kozek
- Vanderbilt Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Thomas M. Bridges
- Vanderbilt Center for Neuroscience Drug Discovery, Nashville, Tennessee 37232, United States
| | - Craig W. Lindsley
- Vanderbilt Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Nashville, Tennessee 37232, United States
| | | | | | - Kevin Wickman
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Corey R. Hopkins
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Carrie K. Jones
- Vanderbilt Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Nashville, Tennessee 37232, United States
| | - C. David Weaver
- Vanderbilt Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Vanderbilt Institute of Chemical Biology, Nashville, Tennessee 37232, United States
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8
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Kozek KA, Du Y, Sharma S, Prael FJ, Spitznagel BD, Kharade SV, Denton JS, Hopkins CR, Weaver CD. Discovery and Characterization of VU0529331, a Synthetic Small-Molecule Activator of Homomeric G Protein-Gated, Inwardly Rectifying, Potassium (GIRK) Channels. ACS Chem Neurosci 2019; 10:358-370. [PMID: 30136838 PMCID: PMC6528656 DOI: 10.1021/acschemneuro.8b00287] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
G protein-gated, inwardly rectifying, potassium (GIRK) channels are important regulators of cellular excitability throughout the body. GIRK channels are heterotetrameric and homotetrameric combinations of the Kir3.1-4 (GIRK1-4) subunits. Different subunit combinations are expressed throughout the central nervous system (CNS) and the periphery, and most of these combinations contain a GIRK1 subunit. For example, the predominance of GIRK channels in the CNS are composed of GIRK1 and GIRK2 subunits, while the GIRK channels in cardiac atrial myocytes are made up mostly of GIRK1 and GIRK4 subunits. Although the vast majority of GIRK channels contain a GIRK1 subunit, discrete populations of cells that express non-GIRK1-containing GIRK (non-GIRK1/X) channels do exist. For instance, dopaminergic neurons in the ventral tegmental area of the brain, associated with addiction and reward, do not express the GIRK1 subunit. Targeting these non-GIRK1/X channels with subunit-selective pharmacological probes could lead to important insights into how GIRK channels are involved in reward and addiction. Such insights may, in turn, reveal therapeutic opportunities for the treatment or prevention of addiction. Previously, our laboratory discovered small molecules that can specifically modulate the activity of GIRK1-containing GIRK channels. However, efforts to generate compounds active on non-GIRK1/X channels from these scaffolds have been unsuccessful. Recently, ivermectin was shown to modulate non-GIRK1/X channels, and historically, ivermectin is known to modulate a wide variety of neuronal channels and receptors. Further, ivermectin is a complex natural product, which makes it a challenging starting point for development of more selective, effective, and potent compounds. Thus, while ivermectin provides proof-of-concept as a non-GIRK1/X channel activator, it is of limited utility. Therefore, we sought to discover a synthetic small molecule that would serve as a starting point for the development of non-GIRK1/X channel modulators. To accomplish this, we used a high-throughput thallium flux assay to screen a 100 000-compound library in search of activators of homomeric GIRK2 channels. Using this approach, we discovered VU0529331, the first synthetic small molecule reported to activate non-GIRK1/X channels, to our knowledge. This discovery represents the first step toward developing potent and selective non-GIRK1/X channel probes. Such molecules will help elucidate the role of GIRK channels in addiction, potentially establishing a foundation for future development of therapies utilizing targeted GIRK channel modulation.
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Affiliation(s)
- Krystian A. Kozek
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
- vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
- vanderbilt Medical Scientist Training Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Yu Du
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
- vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Swagat Sharma
- Department of Pharmaceutical Sciences, Center for Drug Discovery, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Francis J. Prael
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
- vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Brittany D. Spitznagel
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
- vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Sujay V. Kharade
- Department of Anesthesiology, Vanderbilt University, Nashville, Tennessee, USA
| | - Jerod S. Denton
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Anesthesiology, Vanderbilt University, Nashville, Tennessee, USA
| | - Corey R. Hopkins
- Department of Pharmaceutical Sciences, Center for Drug Discovery, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - C. David Weaver
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
- vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
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9
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Shaabani A, Nazeri MT, Afshari R. 5-Amino-pyrazoles: potent reagents in organic and medicinal synthesis. Mol Divers 2018; 23:751-807. [PMID: 30552550 DOI: 10.1007/s11030-018-9902-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 12/04/2018] [Indexed: 12/31/2022]
Abstract
5-Amino-pyrazoles have proven to be a class of fascinating and privileged organic tools for the construction of diverse heterocyclic or fused heterocyclic scaffolds. This review presents comprehensively the applications of 5-amino-pyrazoles as versatile synthetic building blocks in the synthesis of remarkable organic molecules with an emphasis on versatile functionalities. Following a brief introduction of synthesis methods, planning strategies to construct organic compounds, particularly diverse heterocyclic scaffolds, such as poly-substituted heterocyclic compounds and fused heterocyclic compounds via 5-amino-pyrazoles, have been summarized. Fused heterocycles are classified as bicyclic, tricyclic, tetracyclic, and spiro-fused pyrazole derivatives. These outstanding compounds synthesized via wide variety of approaches include conventional reactions, one-pot multi-component reactions, cyclocondensation, cascade/tandem protocols, and coupling reactions. 5-Amino-pyrazoles represent a class of promising functional reagents, similar to the biologically active compounds, highlighted with diverse applications especially in the field of pharmaceutics and medicinal chemistry. Notably, this critical review covers the articles published from 1981 to 2018.
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Affiliation(s)
- Ahmad Shaabani
- Faculty of Chemistry, Shahid Beheshti University, G. C., P. O. Box 19396-4716, Tehran, Iran.
| | - Mohammad Taghi Nazeri
- Faculty of Chemistry, Shahid Beheshti University, G. C., P. O. Box 19396-4716, Tehran, Iran
| | - Ronak Afshari
- Faculty of Chemistry, Shahid Beheshti University, G. C., P. O. Box 19396-4716, Tehran, Iran
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10
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Krebs K, Pfeil EM, Simon K, Grundmann M, Häberlein F, Bautista-Aguilera OM, Gütschow M, Weaver CD, Fleischmann BK, Kostenis E. Label-Free Whole Cell Biosensing for High-Throughput Discovery of Activators and Inhibitors Targeting G Protein-Activated Inwardly Rectifying Potassium Channels. ACS OMEGA 2018; 3:14814-14823. [PMID: 30555990 PMCID: PMC6289404 DOI: 10.1021/acsomega.8b02254] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 10/22/2018] [Indexed: 06/09/2023]
Abstract
Dynamic mass redistribution (DMR) and cellular dielectric spectroscopy (CDS) are label-free biosensor technologies that capture real-time integrated cellular responses upon exposure to extra- and intracellular stimuli. They register signaling routes that are accompanied by cell shape changes and/or molecular movement of cells proximal to the biosensor to which they are attached. Here, we report the unexpected observation that robust DMR and CDS signatures are also elicited upon direct stimulation of G protein-activated inwardly rectifying potassium (GIRK) channels, which are involved in the regulation of excitability in the heart and brain. Using ML297, a small-molecule GIRK activator, along with channel blockers and cytoskeletal network inhibitors, we found that GIRK activation exerts its effects on cell shape by a mechanism which depends on actin but not the microtubule network. Because label-free real-time biosensing (i) quantitatively determines concentration dependency of GIRK activators, (ii) accurately assesses the impact of GIRK channel blockers, (iii) is high throughput-compatible, and (iv) visualizes previously unknown cellular consequences downstream of direct GIRK activation, we do not only provide a novel experimental strategy for identification of GIRK ligands but also an entirely new angle to probe GIRK (ligand) biology. We envision that DMR and CDS may add to the repertoire of technologies for systematic exploitation of ion channel function and, in turn, to the identification of novel GIRK ligands in order to treat cardiovascular and neurological disorders.
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Affiliation(s)
- Katrin
M. Krebs
- Molecular,
Cellular and Pharmacobiology Section, Institute for Pharmaceutical
Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
- Research
Training Group 1873, University of Bonn, Bonn, Germany
| | - Eva M. Pfeil
- Molecular,
Cellular and Pharmacobiology Section, Institute for Pharmaceutical
Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
- Research
Training Group 1873, University of Bonn, Bonn, Germany
| | - Katharina Simon
- Molecular,
Cellular and Pharmacobiology Section, Institute for Pharmaceutical
Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
| | - Manuel Grundmann
- Molecular,
Cellular and Pharmacobiology Section, Institute for Pharmaceutical
Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
| | - Felix Häberlein
- Molecular,
Cellular and Pharmacobiology Section, Institute for Pharmaceutical
Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
| | - Oscar M. Bautista-Aguilera
- Pharmaceutical
Chemistry I, Institute of Pharmacy, University
of Bonn, An der Immenburg
4, 53121 Bonn, Germany
| | - Michael Gütschow
- Pharmaceutical
Chemistry I, Institute of Pharmacy, University
of Bonn, An der Immenburg
4, 53121 Bonn, Germany
| | - C. David Weaver
- Vanderbilt
Institute of Chemical Biology, Department of Pharmacology and Department
of Chemistry, Vanderbilt University, Nashville, 37232 Tennessee, United States
| | - Bernd K. Fleischmann
- Institute
of Physiology I, Life and Brain Center, Medical Faculty, University of Bonn, Sigmund-Freud-Straße 25, 53105 Bonn, Germany
| | - Evi Kostenis
- Molecular,
Cellular and Pharmacobiology Section, Institute for Pharmaceutical
Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
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11
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Expression and relevance of the G protein-gated K + channel in the mouse ventricle. Sci Rep 2018; 8:1192. [PMID: 29352184 PMCID: PMC5775354 DOI: 10.1038/s41598-018-19719-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/08/2018] [Indexed: 12/31/2022] Open
Abstract
The atrial G protein-gated inwardly rectifying K+ (GIRK) channel is a critical mediator of parasympathetic influence on cardiac physiology. Here, we probed the details and relevance of the GIRK channel in mouse ventricle. mRNAs for the atrial GIRK channel subunits (GIRK1, GIRK4), M2 muscarinic receptor (M2R), and RGS6, a negative regulator of atrial GIRK-dependent signaling, were detected in mouse ventricle at relatively low levels. The cholinergic agonist carbachol (CCh) activated small GIRK currents in adult wild-type ventricular myocytes that exhibited relatively slow kinetics and low CCh sensitivity; these currents were absent in ventricular myocytes from Girk1-/- or Girk4-/- mice. While loss of GIRK channels attenuated the CCh-induced shortening of action potential duration and suppression of ventricular myocyte excitability, selective ablation of GIRK channels in ventricle had no effect on heart rate, heart rate variability, or electrocardiogram parameters at baseline or after CCh injection. Additionally, loss of ventricular GIRK channels did not impact susceptibility to ventricular arrhythmias. These data suggest that the mouse ventricular GIRK channel is a GIRK1/GIRK4 heteromer, and show that while it contributes to the cholinergic suppression of ventricular myocyte excitability, this influence does not substantially impact cardiac physiology or ventricular arrhythmogenesis in the mouse.
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12
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Wieting JM, Vadukoot AK, Sharma S, Abney KK, Bridges TM, Daniels JS, Morrison RD, Wickman K, Weaver CD, Hopkins CR. Discovery and Characterization of 1H-Pyrazol-5-yl-2-phenylacetamides as Novel, Non-Urea-Containing GIRK1/2 Potassium Channel Activators. ACS Chem Neurosci 2017; 8:1873-1879. [PMID: 28697302 DOI: 10.1021/acschemneuro.7b00217] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The G protein-gated inwardly-rectifying potassium channels (GIRK, Kir3) are a family of inward-rectifying potassium channels, and there is significant evidence supporting the roles of GIRKs in a number of physiological processes and as potential targets for numerous indications. Previously reported urea containing molecules as GIRK1/2 preferring activators have had significant pharmacokinetic (PK) liabilities. Here we report a novel series of 1H-pyrazolo-5-yl-2-phenylacetamides in an effort to improve upon the PK properties. This series of compounds display nanomolar potency as GIRK1/2 activators with improved brain distribution (rodent Kp > 0.6).
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Affiliation(s)
- Joshua M. Wieting
- Vanderbilt
Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Anish K. Vadukoot
- Department
of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Swagat Sharma
- Department
of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Kristopher K. Abney
- Department
of Neuroscience and Pharmacology, Meharry Medical College, Nashville, Tennessee 37208, United States
| | - Thomas M. Bridges
- Vanderbilt
Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - J. Scott Daniels
- Sano Informed Prescribing, Franklin, Tennessee 37067, United States
| | - Ryan D. Morrison
- Sano Informed Prescribing, Franklin, Tennessee 37067, United States
| | - Kevin Wickman
- Department
of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - C. David Weaver
- Department
of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Vanderbilt
Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Corey R. Hopkins
- Department
of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
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13
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Timmerman JC, Schmitt WW, Widenhoefer RA. Gold-Catalyzed Intermolecular, anti-Markovnikov Hydroarylation of Methylenecyclopropanes with Indoles. Org Lett 2016; 18:4966-4969. [DOI: 10.1021/acs.orglett.6b02431] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jacob C. Timmerman
- French Family Science Center, Duke University, Durham, North Carolina 27708, United States
| | - William W. Schmitt
- French Family Science Center, Duke University, Durham, North Carolina 27708, United States
| | - Ross A. Widenhoefer
- French Family Science Center, Duke University, Durham, North Carolina 27708, United States
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14
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Barber DM, Schönberger M, Burgstaller J, Levitz J, Weaver CD, Isacoff EY, Baier H, Trauner D. Optical control of neuronal activity using a light-operated GIRK channel opener (LOGO). Chem Sci 2015; 7:2347-2352. [PMID: 28090283 PMCID: PMC5234268 DOI: 10.1039/c5sc04084a] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
G-protein coupled inwardly rectifying potassium channels (GIRKs) are ubiquitously expressed throughout the human body and are an integral part of inhibitory signal transduction pathways. Upon binding of Gβγ subunits released from G-protein coupled receptors (GPCRs), GIRK channels open and reduce the activity of excitable cells via hyperpolarization. As such, they play a role in cardiac output, the coordination of movement and cognition. Due to their involvement in a multitude of pathways, the precision control of GIRK channels is an important endeavour. Here, we describe the development of the photoswitchable agonist LOGO (the Light Operated GIRK-channel Opener), which activates GIRK channels in the dark and is rapidly deactivated upon exposure to long wavelength UV irradiation. LOGO is the first K+ channel opener and selectively targets channels that contain the GIRK1 subunit. It can be used to optically silence action potential firing in dissociated hippocampal neurons and LOGO exhibits activity in vivo, controlling the motility of zebrafish larvae in a light dependent fashion. We envisage that LOGO will be a valuable research tool to dissect the function of GIRK channels from other GPCR dependent signalling pathways.
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Affiliation(s)
- David M Barber
- Department of Chemistry and Center for Integrated Protein Science, Ludwig Maximilians University Munich, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Matthias Schönberger
- Department of Chemistry and Center for Integrated Protein Science, Ludwig Maximilians University Munich, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Jessica Burgstaller
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Joshua Levitz
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA
| | - C David Weaver
- Department of Pharmacology and Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
| | - Ehud Y Isacoff
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA; Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Herwig Baier
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Dirk Trauner
- Department of Chemistry and Center for Integrated Protein Science, Ludwig Maximilians University Munich, Butenandtstraße 5-13, 81377 Munich, Germany
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15
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Mayfield J, Blednov YA, Harris RA. Behavioral and Genetic Evidence for GIRK Channels in the CNS: Role in Physiology, Pathophysiology, and Drug Addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 123:279-313. [PMID: 26422988 DOI: 10.1016/bs.irn.2015.05.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
G protein-coupled inwardly rectifying potassium (GIRK) channels are widely expressed throughout the brain and mediate the inhibitory effects of many neurotransmitters. As a result, these channels are important for normal CNS function and have also been implicated in Down syndrome, Parkinson's disease, psychiatric disorders, epilepsy, and drug addiction. Knockout mouse models have provided extensive insight into the significance of GIRK channels under these conditions. This review examines the behavioral and genetic evidence from animal models and genetic association studies in humans linking GIRK channels with CNS disorders. We further explore the possibility that subunit-selective modulators and other advanced research tools will be instrumental in establishing the role of individual GIRK subunits in drug addiction and other relevant CNS diseases and in potentially advancing treatment options for these disorders.
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Affiliation(s)
- Jody Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, USA.
| | - Yuri A Blednov
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, USA
| | - R Adron Harris
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, USA
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16
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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: 2.1] [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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17
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Blichowski M, Shephard A, Armstrong J, Shen L, Cortez MA, Eubanks JH, Snead OC. The GIRK2 subunit is involved in IS-like seizures induced by GABABreceptor agonists. Epilepsia 2015; 56:1081-7. [DOI: 10.1111/epi.13034] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2015] [Indexed: 12/25/2022]
Affiliation(s)
- Monica Blichowski
- Division of Neurology; SickKids Hospital; Toronto Ontario Canada
- Neurosciences and Mental Health Program; Peter Gilgan Centre for Research and Learning; SickKids Hospital; Toronto Ontario Canada
- University of Toronto; Toronto Ontario Canada
| | - Alexander Shephard
- Division of Neurology; SickKids Hospital; Toronto Ontario Canada
- Neurosciences and Mental Health Program; Peter Gilgan Centre for Research and Learning; SickKids Hospital; Toronto Ontario Canada
| | - Jessica Armstrong
- Division of Neurology; SickKids Hospital; Toronto Ontario Canada
- Neurosciences and Mental Health Program; Peter Gilgan Centre for Research and Learning; SickKids Hospital; Toronto Ontario Canada
| | - Liqing Shen
- Neurosciences and Mental Health Program; Peter Gilgan Centre for Research and Learning; SickKids Hospital; Toronto Ontario Canada
| | - Miguel A. Cortez
- Division of Neurology; SickKids Hospital; Toronto Ontario Canada
- Neurosciences and Mental Health Program; Peter Gilgan Centre for Research and Learning; SickKids Hospital; Toronto Ontario Canada
- University of Toronto; Toronto Ontario Canada
- Department of Paediatrics; SickKids Hospital; Toronto Ontario Canada
| | | | - O. Carter Snead
- Division of Neurology; SickKids Hospital; Toronto Ontario Canada
- Neurosciences and Mental Health Program; Peter Gilgan Centre for Research and Learning; SickKids Hospital; Toronto Ontario Canada
- University of Toronto; Toronto Ontario Canada
- Department of Paediatrics; SickKids Hospital; Toronto Ontario Canada
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18
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GIRK Channels: A Potential Link Between Learning and Addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 123:239-77. [PMID: 26422987 DOI: 10.1016/bs.irn.2015.05.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The ability of drug-associated cues to reinitiate drug craving and seeking, even after long periods of abstinence, has led to the hypothesis that addiction represents a form of pathological learning, in which drugs of abuse hijack normal learning and memory processes to support long-term addictive behaviors. In this chapter, we review evidence suggesting that G protein-gated inwardly rectifying potassium (GIRK/Kir3) channels are one mechanism through which numerous drugs of abuse can modulate learning and memory processes. We will examine the role of GIRK channels in two forms of experience-dependent long-term changes in neuronal function: homeostatic plasticity and synaptic plasticity. We will also discuss how drug-induced changes in GIRK-mediated signaling can lead to changes that support the development and maintenance of addiction.
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19
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Wen W, Wu W, Weaver CD, Lindsley CW. Discovery of potent and selective GIRK1/2 modulators via 'molecular switches' within a series of 1-(3-cyclopropyl-1-phenyl-1H-pyrazol-5-yl)ureas. Bioorg Med Chem Lett 2014; 24:5102-6. [PMID: 25264075 DOI: 10.1016/j.bmcl.2014.08.061] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/21/2014] [Accepted: 08/27/2014] [Indexed: 01/14/2023]
Abstract
This Letter describes the on-going SAR efforts based on ML297, a potent, efficacious and selective GIRK1/2 activator (∼ 10-fold vs GIRK1/4 and inactive on GIRK2/3) via an iterative parallel synthesis approach. The chemical optimization at the 3-position of pyrazole within ML297 indicated that various functionalized 3-cyclopropyl moieties modulated GIRK pharmacology between inhibitor/activator within a series of 1-(3-cyclopropyl-1-phenyl-1H-pyrazol-5-yl)ureas. Importantly, novel 'molecular switches' that modulated the mode of pharmacology from inhibitor to activator was discovered on both the 3-cyclopropyl and N-phenyl moiety of the pyrazole core, providing the first highly selective GIRK1/2 activator.
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Affiliation(s)
- Wandong Wen
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Wenjun Wu
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - C David Weaver
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University/Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Specialized Chemistry Center for Probe Development (MLPCN), Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University/Vanderbilt University Medical Center, Nashville, TN 37232, USA.
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20
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Mechanisms underlying the activation of G-protein-gated inwardly rectifying K+ (GIRK) channels by the novel anxiolytic drug, ML297. Proc Natl Acad Sci U S A 2014; 111:10755-60. [PMID: 25002517 DOI: 10.1073/pnas.1405190111] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
ML297 was recently identified as a potent and selective small molecule agonist of G-protein-gated inwardly rectifying K(+) (GIRK/Kir3) channels. Here, we show ML297 selectively activates recombinant neuronal GIRK channels containing the GIRK1 subunit in a manner that requires phosphatidylinositol-4,5-bisphosphate (PIP2), but is otherwise distinct from receptor-induced, G-protein-dependent channel activation. Two amino acids unique to the pore helix (F137) and second membrane-spanning (D173) domain of GIRK1 were identified as necessary and sufficient for the selective activation of GIRK channels by ML297. Further investigation into the behavioral effects of ML297 revealed that in addition to its known antiseizure efficacy, ML297 decreases anxiety-related behavior without sedative or addictive liabilities. Importantly, the anxiolytic effect of ML297 was lost in mice lacking GIRK1. Thus, activation of GIRK1-containing channels by ML297 or derivatives may represent a new approach to the treatment of seizure and/or anxiety disorders.
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21
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Nava-Mesa MO, Jiménez-Díaz L, Yajeya J, Navarro-Lopez JD. GABAergic neurotransmission and new strategies of neuromodulation to compensate synaptic dysfunction in early stages of Alzheimer's disease. Front Cell Neurosci 2014; 8:167. [PMID: 24987334 PMCID: PMC4070063 DOI: 10.3389/fncel.2014.00167] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 06/02/2014] [Indexed: 01/06/2023] Open
Abstract
Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by cognitive decline, brain atrophy due to neuronal and synapse loss, and formation of two pathological lesions: extracellular amyloid plaques, composed largely of amyloid-beta peptide (Aβ), and neurofibrillary tangles formed by intracellular aggregates of hyperphosphorylated tau protein. Lesions mainly accumulate in brain regions that modulate cognitive functions such as the hippocampus, septum or amygdala. These brain structures have dense reciprocal glutamatergic, cholinergic, and GABAergic connections and their relationships directly affect learning and memory processes, so they have been proposed as highly susceptible regions to suffer damage by Aβ during AD course. Last findings support the emerging concept that soluble Aβ peptides, inducing an initial stage of synaptic dysfunction which probably starts 20–30 years before the clinical onset of AD, can perturb the excitatory–inhibitory balance of neural circuitries. In turn, neurotransmission imbalance will result in altered network activity that might be responsible of cognitive deficits in AD. Therefore, Aβ interactions on neurotransmission systems in memory-related brain regions such as amygdaloid complex, medial septum or hippocampus are critical in cognitive functions and appear as a pivotal target for drug design to improve learning and dysfunctions that manifest with age. Since treatments based on glutamatergic and cholinergic pharmacology in AD have shown limited success, therapies combining modulators of different neurotransmission systems including recent findings regarding the GABAergic system, emerge as a more useful tool for the treatment, and overall prevention, of this dementia. In this review, focused on inhibitory systems, we will analyze pharmacological strategies to compensate neurotransmission imbalance that might be considered as potential therapeutic interventions in AD.
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Affiliation(s)
| | - Lydia Jiménez-Díaz
- Neurophysiology and Behavior Lab, Centro Regional de Investigaciones Biomédicas, School of Medicine of Ciudad Real, University of Castilla-La Mancha Ciudad Real, Spain
| | - Javier Yajeya
- Department of Physiology and Pharmacology, University of Salamanca Salamanca, Spain
| | - Juan D Navarro-Lopez
- Neurophysiology and Behavior Lab, Centro Regional de Investigaciones Biomédicas, School of Medicine of Ciudad Real, University of Castilla-La Mancha Ciudad Real, Spain
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22
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Luján R, Marron Fernandez de Velasco E, Aguado C, Wickman K. New insights into the therapeutic potential of Girk channels. Trends Neurosci 2013; 37:20-9. [PMID: 24268819 DOI: 10.1016/j.tins.2013.10.006] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 10/24/2013] [Accepted: 10/25/2013] [Indexed: 01/01/2023]
Abstract
G protein-dependent signaling pathways control the activity of excitable cells of the nervous system and heart, and are the targets of neurotransmitters, clinically relevant drugs, and drugs of abuse. G protein-gated inwardly rectifying potassium (K(+)) (Girk/Kir3) channels are a key effector in inhibitory signaling pathways. Girk-dependent signaling contributes to nociception and analgesia, reward-related behavior, mood, cognition, and heart-rate regulation, and has been linked to epilepsy, Down syndrome, addiction, and arrhythmias. We discuss recent advances in our understanding of Girk channel structure, organization in signaling complexes, and plasticity, as well as progress on the development of subunit-selective Girk modulators. These findings offer new hope for the selective manipulation of Girk channels to treat a variety of debilitating afflictions.
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Affiliation(s)
- Rafael Luján
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/Almansa 14, 02008 Albacete, Spain.
| | | | - Carolina Aguado
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/Almansa 14, 02008 Albacete, Spain
| | - Kevin Wickman
- Department of Pharmacology, University of Minnesota, 321 Church Street South East, Minneapolis, MN 55455, USA.
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