1
|
Kwan C, Lévesque C, Bédard D, Frouni I, Yesuf JM, Hamadjida A, Lévesque D, Clarke PB, Huot P. Autoradiographic labelling of 5-HT 3 receptors in the hemi-parkinsonian rat brain. Neurosci Res 2021; 177:135-144. [PMID: 34954302 DOI: 10.1016/j.neures.2021.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/16/2021] [Accepted: 12/21/2021] [Indexed: 11/26/2022]
Abstract
L-3,4-dihydroxyphenylalanine (L-DOPA) is the mainstay treatment for Parkinson's disease, but its effectiveness during early disease is marred by the eventual development of L-DOPA induced dyskinesia. In hemi-parkinsonian rats, the serotonin type 3 (5-HT3) antagonists ondansetron and granisetron alleviated dyskinesia induced by L-DOPA without impeding its anti-parkinsonian action; in parkinsonian marmosets, ondansetron alleviated dyskinesia and enhanced L-DOPA anti-parkinsonian action. Here, we sought to gain insight into the mechanisms governing the anti-dyskinetic action of 5-HT3 antagonists and measured their levels across different brain, using [3H]GR65630 autoradiographic binding. Brain sections were chosen from 6-hydroxydopamine (6-OHDA)-lesioned rats exhibiting abnormal involuntary movements (AIMs), as well as L-DOPA-naïve 6-OHDA and sham-lesioned animals. [3H]GR65630 binding increased in the ipsilateral subthalamic nucleus of 6-OHDA-lesioned rats with mild and severe AIMs, (3-fold changes, P < 0.001). [3H]GR65630 binding also increased in the ipsilateral entopeduncular nucleus and thalamus of 6-OHDA-lesioned rats with severe AIMs (75% and 88%, P < 0.05). AIMs scores negatively correlated with [3H]GR65630 binding in the ipsilateral dorsolateral striatum and contralateral subthalamic nucleus (P < 0.05). These results suggest that alterations in 5-HT3 mediated neurotransmission may contribute to the pathophysiology of L-DOPA induced dyskinesia.
Collapse
Affiliation(s)
- Cynthia Kwan
- Neurodegenerative Disease Group, Montreal Neurological Institute-Hospital (The Neuro), Montreal, QC, Canada
| | | | - Dominique Bédard
- Neurodegenerative Disease Group, Montreal Neurological Institute-Hospital (The Neuro), Montreal, QC, Canada
| | - Imane Frouni
- Neurodegenerative Disease Group, Montreal Neurological Institute-Hospital (The Neuro), Montreal, QC, Canada; Département de pharmacologie et physiologie, Université de Montréal, Montreal, QC, Canada
| | - Jemal M Yesuf
- Neurodegenerative Disease Group, Montreal Neurological Institute-Hospital (The Neuro), Montreal, QC, Canada
| | - Adjia Hamadjida
- Neurodegenerative Disease Group, Montreal Neurological Institute-Hospital (The Neuro), Montreal, QC, Canada
| | - Daniel Lévesque
- Faculté de pharmacie, Université de Montréal, Montreal, QC, Canada
| | - Paul Bs Clarke
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Philippe Huot
- Neurodegenerative Disease Group, Montreal Neurological Institute-Hospital (The Neuro), Montreal, QC, Canada; Département de pharmacologie et physiologie, Université de Montréal, Montreal, QC, Canada; Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada; Movement Disorder Clinic, Division of Neurology, Department of Neuroscience, McGill University Health Centre, Montreal, QC, Canada.
| |
Collapse
|
2
|
Borgarelli C, Klingl YE, Escamilla-Ayala A, Munck S, Van Den Bosch L, De Borggraeve WM, Ismalaj E. Lighting Up the Plasma Membrane: Development and Applications of Fluorescent Ligands for Transmembrane Proteins. Chemistry 2021; 27:8605-8641. [PMID: 33733502 DOI: 10.1002/chem.202100296] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Indexed: 12/16/2022]
Abstract
Despite the fact that transmembrane proteins represent the main therapeutic targets for decades, complete and in-depth knowledge about their biochemical and pharmacological profiling is not fully available. In this regard, target-tailored small-molecule fluorescent ligands are a viable approach to fill in the missing pieces of the puzzle. Such tools, coupled with the ability of high-precision optical techniques to image with an unprecedented resolution at a single-molecule level, helped unraveling many of the conundrums related to plasma proteins' life-cycle and druggability. Herein, we review the recent progress made during the last two decades in fluorescent ligand design and potential applications in fluorescence microscopy of voltage-gated ion channels, ligand-gated ion channels and G-coupled protein receptors.
Collapse
Affiliation(s)
- Carlotta Borgarelli
- Department of Chemistry, Molecular Design and Synthesis, KU Leuven Campus Arenberg Celestijnenlaan 200F -, box 2404, 3001, Leuven, Belgium
| | - Yvonne E Klingl
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Laboratory of Neurobiology, VIB, Center for Brain &, Disease Research, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Abril Escamilla-Ayala
- Center for Brain & Disease Research, & VIB BioImaging Core, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Department of Neurosciences, Leuven Brain Institute, KU Leuven, Campus Gasthuisberg O&N5 - box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Sebastian Munck
- Center for Brain & Disease Research, & VIB BioImaging Core, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Department of Neurosciences, Leuven Brain Institute, KU Leuven, Campus Gasthuisberg O&N5 - box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Laboratory of Neurobiology, VIB, Center for Brain &, Disease Research, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Wim M De Borggraeve
- Department of Chemistry, Molecular Design and Synthesis, KU Leuven Campus Arenberg Celestijnenlaan 200F -, box 2404, 3001, Leuven, Belgium
| | - Ermal Ismalaj
- Department of Chemistry, Molecular Design and Synthesis, KU Leuven Campus Arenberg Celestijnenlaan 200F -, box 2404, 3001, Leuven, Belgium
| |
Collapse
|
3
|
Răducă M, Ene CD, Ionescu S, Florea M, Mădălan AM. Coordination polymers and a dinuclear complex constructed from zinc(II) ions and fluorescein: iodine adsorption and optical properties. J COORD CHEM 2019. [DOI: 10.1080/00958972.2019.1605442] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Mihai Răducă
- Inorganic Chemistry Department, Faculty of Chemistry, University of Bucharest, Bucharest, Romania
| | - Cristian D. Ene
- Inorganic Chemistry Department, Faculty of Chemistry, University of Bucharest, Bucharest, Romania
- Coordination and Supramolecular Chemistry Laboratory, “Ilie Murgulescu” Institute of Physical Chemistry of the Romanian Academy, Bucharest, Romania
| | - Sorana Ionescu
- Department of Physical Chemistry, Faculty of Chemistry, University of Bucharest, Bucharest, Romania
| | - Mihaela Florea
- Inorganic Chemistry Department, Faculty of Chemistry, University of Bucharest, Bucharest, Romania
- National Institute of Material Physics, Magurele, Romania
| | - Augustin M. Mădălan
- Inorganic Chemistry Department, Faculty of Chemistry, University of Bucharest, Bucharest, Romania
| |
Collapse
|
4
|
Otvos RA, Still KBM, Somsen GW, Smit AB, Kool J. Drug Discovery on Natural Products: From Ion Channels to nAChRs, from Nature to Libraries, from Analytics to Assays. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2019; 24:362-385. [PMID: 30682257 PMCID: PMC6484542 DOI: 10.1177/2472555218822098] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 11/16/2018] [Accepted: 12/07/2018] [Indexed: 12/21/2022]
Abstract
Natural extracts are complex mixtures that may be rich in useful bioactive compounds and therefore are attractive sources for new leads in drug discovery. This review describes drug discovery from natural products and in explaining this process puts the focus on ion-channel drug discovery. In particular, the identification of bioactives from natural products targeting nicotinic acetylcholine receptors (nAChRs) and serotonin type 3 receptors (5-HT3Rs) is discussed. The review is divided into three parts: "Targets," "Sources," and "Approaches." The "Targets" part will discuss the importance of ion-channel drug targets in general, and the α7-nAChR and 5-HT3Rs in particular. The "Sources" part will discuss the relevance for drug discovery of finding bioactive compounds from various natural sources such as venoms and plant extracts. The "Approaches" part will give an overview of classical and new analytical approaches that are used for the identification of new bioactive compounds with the focus on targeting ion channels. In addition, a selected overview is given of traditional venom-based drug discovery approaches and of diverse hyphenated analytical systems used for screening complex bioactive mixtures including venoms.
Collapse
Affiliation(s)
- Reka A. Otvos
- The Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Kristina B. M. Still
- The Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Govert W. Somsen
- The Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - August B. Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Jeroen Kool
- The Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
5
|
Jack T, Leuenberger M, Ruepp MD, Vernekar SKV, Thompson AJ, Braga-Lagache S, Heller M, Lochner M. Mapping the Orthosteric Binding Site of the Human 5-HT 3 Receptor Using Photo-cross-linking Antagonists. ACS Chem Neurosci 2019; 10:438-450. [PMID: 30149702 DOI: 10.1021/acschemneuro.8b00327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The serotonin-gated 5-HT3 receptor is a ligand-gated ion channel. Its location at the synapse in the central and peripheral nervous system has rendered it a prime pharmacological target, for example, for antiemetic drugs that bind with high affinity to the neurotransmitter binding site and prevent the opening of the channel. Advances in structural biology techniques have led to a surge of disclosed three-dimensional receptor structures; however, solving ligand-bound high-resolution 5-HT3 receptor structures has not been achieved to date. Ligand binding poses in the orthosteric binding site have been largely predicted from mutagenesis and docking studies. We report the synthesis of a series of photo-cross-linking compounds whose structures are based on the clinically used antiemetic drug granisetron (Kytril). These displaced [3H]granisetron from the orthosteric binding site with low nanomolar affinities and showed specific photo-cross-linking with the human 5-HT3 receptor. Detailed analysis by protein-MS/MS identified a residue (Met-228) near the tip of binding loop C as the covalent modification site.
Collapse
Affiliation(s)
- Thomas Jack
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Michele Leuenberger
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Marc-David Ruepp
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | | | - Andrew J. Thompson
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K
| | - Sophie Braga-Lagache
- Department of BioMedical Research, Mass Spectrometry and Proteomics Laboratory, University of Bern, Inselspital, 3010 Bern, Switzerland
| | - Manfred Heller
- Department of BioMedical Research, Mass Spectrometry and Proteomics Laboratory, University of Bern, Inselspital, 3010 Bern, Switzerland
| | - Martin Lochner
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| |
Collapse
|
6
|
Lee A, Tsekouras K, Calderon C, Bustamante C, Pressé S. Unraveling the Thousand Word Picture: An Introduction to Super-Resolution Data Analysis. Chem Rev 2017; 117:7276-7330. [PMID: 28414216 PMCID: PMC5487374 DOI: 10.1021/acs.chemrev.6b00729] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Super-resolution microscopy provides direct insight into fundamental biological processes occurring at length scales smaller than light's diffraction limit. The analysis of data at such scales has brought statistical and machine learning methods into the mainstream. Here we provide a survey of data analysis methods starting from an overview of basic statistical techniques underlying the analysis of super-resolution and, more broadly, imaging data. We subsequently break down the analysis of super-resolution data into four problems: the localization problem, the counting problem, the linking problem, and what we've termed the interpretation problem.
Collapse
Affiliation(s)
- Antony Lee
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California at Berkeley, Berkeley, California 94720, United States
| | - Konstantinos Tsekouras
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Department of Physics, Arizona State University, Tempe, Arizona 85287, United States
| | | | - Carlos Bustamante
- Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California at Berkeley, Berkeley, California 94720, United States
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, California 94720, United States
- Institute for Quantitative Biosciences-QB3, University of California at Berkeley, Berkeley, California 94720, United States
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, United States
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, United States
- Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, California 94720, United States
- Kavli Energy Nanosciences Institute, University of California at Berkeley, Berkeley, California 94720, United States
| | - Steve Pressé
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Department of Chemistry and Chemical Biology, Indiana University–Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
- Department of Cell and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana 46202, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Department of Physics, Arizona State University, Tempe, Arizona 85287, United States
| |
Collapse
|
7
|
Ruepp MD, Wei H, Leuenberger M, Lochner M, Thompson AJ. The binding orientations of structurally-related ligands can differ; A cautionary note. Neuropharmacology 2017; 119:48-61. [PMID: 28137449 PMCID: PMC5464333 DOI: 10.1016/j.neuropharm.2017.01.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 01/13/2017] [Accepted: 01/24/2017] [Indexed: 11/19/2022]
Abstract
Crystal structures can identify ligand-receptor interactions and assist the development of novel therapeutics, but experimental challenges sometimes necessitate the use of homologous proteins. Tropisetron is an orthosteric ligand at both 5-HT3 and α7 nACh receptors and its binding orientation has been determined in the structural homologue AChBP (pdbid: 2WNC). Co-crystallisation with a structurally-related ligand, granisetron, reveals an almost identical orientation (pdbid; 2YME). However, there is a >1000-fold difference in the affinity of tropisetron at 5-HT3 versus α7 nACh receptors, and α7 nACh receptors do not bind granisetron. These striking pharmacological differences prompt questions about which receptor the crystal structures most closely represent and whether the ligand orientations are correct. Here we probe the binding orientation of tropisetron and granisetron at 5-HT3 receptors by in silico modelling and docking, radioligand binding on cysteine-substituted 5-HT3 receptor mutants transiently expressed in HEK 293 cells, and synthetic modification of the ligands. For 15 of the 23 cysteine substitutions, the effects on tropisetron and granisetron were different. Structure-activity relationships on synthesised derivatives of both ligands were also consistent with different orientations, revealing that contrary to the crystallographic evidence from AChBP, the two ligands adopt different orientations in the 5-HT3 receptor binding site. Our results show that even quite structurally similar molecules can adopt different orientations in the same binding site, and that caution may be needed when using homologous proteins to predict ligand binding. The drugs granisetron and tropisetron are structurally similar. Crystals of them bound to AChBP suggest they have similar binding orientations. At 5-HT3R, the effects of mutagenesis indicate that their orientations differ. SAR on both of these drugs also supports different orientations.
Collapse
Affiliation(s)
- Marc-David Ruepp
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Hao Wei
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Michele Leuenberger
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Martin Lochner
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland.
| | | |
Collapse
|
8
|
Mu L, Müller Herde A, Rüefli PM, Sladojevich F, Milicevic Sephton S, Krämer SD, Thompson AJ, Schibli R, Ametamey SM, Lochner M. Synthesis and Pharmacological Evaluation of [ 11C]Granisetron and [ 18F]Fluoropalonosetron as PET Probes for 5-HT 3 Receptor Imaging. ACS Chem Neurosci 2016; 7:1552-1564. [PMID: 27571447 DOI: 10.1021/acschemneuro.6b00192] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Serotonin-gated ionotropic 5-HT3 receptors are the major pharmacological targets for antiemetic compounds. Furthermore, they have become a focus for the treatment of irritable bowel syndrome (IBS) and there is some evidence that pharmacological modulation of 5-HT3 receptors might alleviate symptoms of other neurological disorders. Highly selective, high-affinity antagonists, such as granisetron (Kytril) and palonosetron (Aloxi), belong to a family of drugs (the "setrons") that are well established for clinical use. To enable us to better understand the actions of these drugs in vivo, we report the synthesis of 8-fluoropalonosetron (15) that has a binding affinity (Ki = 0.26 ± 0.05 nM) similar to the parent drug (Ki = 0.21 ± 0.03 nM). We radiolabeled 15 by nucleophilic 18F-fluorination of an unsymmetrical diaryliodonium palonosetron precursor and achieved the radiosynthesis of 1-(methyl-11C)-N-granisetron ([11C]2) through N-alkylation with [11C]CH3I, respectively. Both compounds [18F]15 (chemical and radiochemical purity >95%, specific activity 41 GBq/μmol) and [11C]2 (chemical and radiochemical purity ≥99%, specific activity 170 GBq/μmol) were evaluated for their utility as positron emission tomography (PET) probes. Using mouse and rat brain slices, in vitro autoradiography with both [18F]15 and [11C]2 revealed a heterogeneous and displaceable binding in cortical and hippocampal regions that are known to express 5-HT3 receptors at significant levels. Subsequent PET experiments suggested that [18F]15 and [11C]2 are of limited utility for the PET imaging of brain 5-HT3 receptors in vivo.
Collapse
Affiliation(s)
- Linjing Mu
- Department
of Nuclear Medicine, University Hospital Zürich, Rämistrasse
100, 8091 Zürich, Switzerland
| | - Adrienne Müller Herde
- Center for Radiopharmaceutical
Sciences of ETH, PSI and USZ, Vladimir-Prelog-Weg
4, 8093 Zürich, Switzerland
| | - Pascal M. Rüefli
- Department
of Chemistry and Biochemistry, University of Bern, Freiestrasse
3, 3012 Bern, Switzerland
| | - Filippo Sladojevich
- Center for Radiopharmaceutical
Sciences of ETH, PSI and USZ, Vladimir-Prelog-Weg
4, 8093 Zürich, Switzerland
| | - Selena Milicevic Sephton
- Center for Radiopharmaceutical
Sciences of ETH, PSI and USZ, Vladimir-Prelog-Weg
4, 8093 Zürich, Switzerland
| | - Stefanie D. Krämer
- Center for Radiopharmaceutical
Sciences of ETH, PSI and USZ, Vladimir-Prelog-Weg
4, 8093 Zürich, Switzerland
| | - Andrew J. Thompson
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Roger Schibli
- Center for Radiopharmaceutical
Sciences of ETH, PSI and USZ, Vladimir-Prelog-Weg
4, 8093 Zürich, Switzerland
| | - Simon M. Ametamey
- Center for Radiopharmaceutical
Sciences of ETH, PSI and USZ, Vladimir-Prelog-Weg
4, 8093 Zürich, Switzerland
| | - Martin Lochner
- Department
of Chemistry and Biochemistry, University of Bern, Freiestrasse
3, 3012 Bern, Switzerland
| |
Collapse
|
9
|
Lochner M, Thompson AJ. The muscarinic antagonists scopolamine and atropine are competitive antagonists at 5-HT3 receptors. Neuropharmacology 2016; 108:220-8. [PMID: 27108935 PMCID: PMC4920643 DOI: 10.1016/j.neuropharm.2016.04.027] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 03/09/2016] [Accepted: 04/20/2016] [Indexed: 11/30/2022]
Abstract
Scopolamine is a high affinity muscarinic antagonist that is used for the prevention of post-operative nausea and vomiting. 5-HT3 receptor antagonists are used for the same purpose and are structurally related to scopolamine. To examine whether 5-HT3 receptors are affected by scopolamine we examined the effects of this drug on the electrophysiological and ligand binding properties of 5-HT3A receptors expressed in Xenopus oocytes and HEK293 cells, respectively. 5-HT3 receptor-responses were reversibly inhibited by scopolamine with an IC50 of 2.09 μM. Competitive antagonism was shown by Schild plot (pA2 = 5.02) and by competition with the 5-HT3 receptor antagonists [(3)H]granisetron (Ki = 6.76 μM) and G-FL (Ki = 4.90 μM). The related molecule, atropine, similarly inhibited 5-HT evoked responses in oocytes with an IC50 of 1.74 μM, and competed with G-FL with a Ki of 7.94 μM. The reverse experiment revealed that granisetron also competitively bound to muscarinic receptors (Ki = 6.5 μM). In behavioural studies scopolamine is used to block muscarinic receptors and induce a cognitive deficit, and centrally administered concentrations can exceed the IC50 values found here. It is therefore possible that 5-HT3 receptors are also inhibited. Studies that utilise higher concentrations of scopolamine should be mindful of these potential off-target effects.
Collapse
Affiliation(s)
- Martin Lochner
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, Bern, CH-3012, Switzerland.
| | - Andrew J Thompson
- Department of Pharmacology, Tennis Court Road, Cambridge, CB2 1PD, UK.
| |
Collapse
|
10
|
Lukinavičius G, Reymond L, Umezawa K, Sallin O, D'Este E, Göttfert F, Ta H, Hell SW, Urano Y, Johnsson K. Fluorogenic Probes for Multicolor Imaging in Living Cells. J Am Chem Soc 2016; 138:9365-8. [PMID: 27420907 DOI: 10.1021/jacs.6b04782] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Here we present a far-red, silicon-rhodamine-based fluorophore (SiR700) for live-cell multicolor imaging. SiR700 has excitation and emission maxima at 690 and 715 nm, respectively. SiR700-based probes for F-actin, microtubules, lysosomes, and SNAP-tag are fluorogenic, cell-permeable, and compatible with superresolution microscopy. In conjunction with probes based on the previously introduced carboxy-SiR650, SiR700-based probes permit multicolor live-cell superresolution microscopy in the far-red, thus significantly expanding our capacity for imaging living cells.
Collapse
Affiliation(s)
- Gražvydas Lukinavičius
- Institute of Bioengineering, NCCR in Chemical Biology, Institute of Chemical Sciences and Engineering (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne, Switzerland.,Department of NanoBiophotonics, Max-Planck-Institute for Biophysical Chemistry , Am Fassberg 11, 37077 Göttingen, Germany
| | - Luc Reymond
- Institute of Bioengineering, NCCR in Chemical Biology, Institute of Chemical Sciences and Engineering (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne, Switzerland
| | - Keitaro Umezawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo , 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8654, Japan
| | - Olivier Sallin
- Institute of Bioengineering, NCCR in Chemical Biology, Institute of Chemical Sciences and Engineering (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne, Switzerland
| | - Elisa D'Este
- Department of NanoBiophotonics, Max-Planck-Institute for Biophysical Chemistry , Am Fassberg 11, 37077 Göttingen, Germany
| | - Fabian Göttfert
- Department of NanoBiophotonics, Max-Planck-Institute for Biophysical Chemistry , Am Fassberg 11, 37077 Göttingen, Germany
| | - Haisen Ta
- Department of NanoBiophotonics, Max-Planck-Institute for Biophysical Chemistry , Am Fassberg 11, 37077 Göttingen, Germany
| | - Stefan W Hell
- Department of NanoBiophotonics, Max-Planck-Institute for Biophysical Chemistry , Am Fassberg 11, 37077 Göttingen, Germany
| | - Yasuteru Urano
- Graduate School of Pharmaceutical Sciences, The University of Tokyo , 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8654, Japan
| | - Kai Johnsson
- Institute of Bioengineering, NCCR in Chemical Biology, Institute of Chemical Sciences and Engineering (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne, Switzerland
| |
Collapse
|
11
|
Jarvis GE, Barbosa R, Thompson AJ. Noncompetitive Inhibition of 5-HT3 Receptors by Citral, Linalool, and Eucalyptol Revealed by Nonlinear Mixed-Effects Modeling. J Pharmacol Exp Ther 2015; 356:549-62. [PMID: 26669427 PMCID: PMC5378937 DOI: 10.1124/jpet.115.230011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/14/2015] [Indexed: 12/15/2022] Open
Abstract
Citral, eucalyptol, and linalool are widely used as flavorings, fragrances, and cosmetics. Here, we examined their effects on electrophysiological and binding properties of human 5-HT3 receptors expressed in Xenopus oocytes and human embryonic kidney 293 cells, respectively. Data were analyzed using nonlinear mixed-effects modeling to account for random variance in the peak current response between oocytes. The oils caused an insurmountable inhibition of 5‐HT–evoked currents (citral IC50 = 120 µM; eucalyptol = 258 µM; linalool = 141 µM) and did not compete with fluorescently labeled granisetron, suggesting a noncompetitive mechanism of action. Inhibition was not use‐dependent but required a 30-second preapplication. Compound washout caused a slow (∼180 seconds) but complete recovery. Coapplication of the oils with bilobalide or diltiazem indicated they did not bind at the same locations as these channel blockers. Homology modeling and ligand docking predicted binding to a transmembrane cavity at the interface of adjacent subunits. Liquid chromatography coupled to mass spectrometry showed that an essential oil extracted from Lippia alba contained 75.9% citral. This inhibited expressed 5‐HT3 receptors (IC50 = 45 µg ml−1) and smooth muscle contractions in rat trachea (IC50 = 200 µg ml−1) and guinea pig ileum (IC50 = 20 µg ml−1), providing a possible mechanistic explanation for why this oil has been used to treat gastrointestinal and respiratory ailments. These results demonstrate that citral, eucalyptol, and linalool inhibit 5-HT3 receptors, and their binding to a conserved cavity suggests a valuable target for novel allosteric modulators.
Collapse
Affiliation(s)
- Gavin E Jarvis
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (G.E.J.); Mestrado em Bioprospecção Molecular, Universidade Regional do Cariri, Crato, Brazil (R.B.); and Department of Pharmacology, Cambridge, United Kingdom (A.J.T.)
| | - Roseli Barbosa
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (G.E.J.); Mestrado em Bioprospecção Molecular, Universidade Regional do Cariri, Crato, Brazil (R.B.); and Department of Pharmacology, Cambridge, United Kingdom (A.J.T.)
| | - Andrew J Thompson
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (G.E.J.); Mestrado em Bioprospecção Molecular, Universidade Regional do Cariri, Crato, Brazil (R.B.); and Department of Pharmacology, Cambridge, United Kingdom (A.J.T.)
| |
Collapse
|
12
|
Imaging and manipulating proteins in live cells through covalent labeling. Nat Chem Biol 2015; 11:917-23. [PMID: 26575238 DOI: 10.1038/nchembio.1959] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/14/2015] [Indexed: 12/19/2022]
Abstract
The past 20 years have witnessed the advent of numerous technologies to specifically and covalently label proteins in cellulo and in vivo with synthetic probes. These technologies range from self-labeling proteins tags to non-natural amino acids, and the question is no longer how we can specifically label a given protein but rather with what additional functionality we wish to equip it. In addition, progress in fields such as super-resolution microscopy and genome editing have either provided additional motivation to label proteins with advanced synthetic probes or removed some of the difficulties of conducting such experiments. By focusing on two particular applications, live-cell imaging and the generation of reversible protein switches, we outline the opportunities and challenges of the field and how the synergy between synthetic chemistry and protein engineering will make it possible to conduct experiments that are not feasible with conventional approaches.
Collapse
|
13
|
Barden AO, Goler AS, Humphreys SC, Tabatabaei S, Lochner M, Ruepp MD, Jack T, Simonin J, Thompson AJ, Jones JP, Brozik JA. Tracking individual membrane proteins and their biochemistry: The power of direct observation. Neuropharmacology 2015; 98:22-30. [PMID: 25998277 DOI: 10.1016/j.neuropharm.2015.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 04/13/2015] [Accepted: 05/06/2015] [Indexed: 10/23/2022]
Abstract
The advent of single molecule fluorescence microscopy has allowed experimental molecular biophysics and biochemistry to transcend traditional ensemble measurements, where the behavior of individual proteins could not be precisely sampled. The recent explosion in popularity of new super-resolution and super-localization techniques coupled with technical advances in optical designs and fast highly sensitive cameras with single photon sensitivity and millisecond time resolution have made it possible to track key motions, reactions, and interactions of individual proteins with high temporal resolution and spatial resolution well beyond the diffraction limit. Within the purview of membrane proteins and ligand gated ion channels (LGICs), these outstanding advances in single molecule microscopy allow for the direct observation of discrete biochemical states and their fluctuation dynamics. Such observations are fundamentally important for understanding molecular-level mechanisms governing these systems. Examples reviewed here include the effects of allostery on the stoichiometry of ligand binding in the presence of fluorescent ligands; the observation of subdomain partitioning of membrane proteins due to microenvironment effects; and the use of single particle tracking experiments to elucidate characteristics of membrane protein diffusion and the direct measurement of thermodynamic properties, which govern the free energy landscape of protein dimerization. The review of such characteristic topics represents a snapshot of efforts to push the boundaries of fluorescence microscopy of membrane proteins to the absolute limit. This article is part of the Special Issue entitled 'Fluorescent Tools in Neuropharmacology'.
Collapse
Affiliation(s)
- Adam O Barden
- Department of Chemistry, Washington State University, PO Box 644630, Pullman, WA, 99164-4630, United States
| | - Adam S Goler
- Department of Chemistry, Washington State University, PO Box 644630, Pullman, WA, 99164-4630, United States
| | - Sara C Humphreys
- Department of Chemistry, Washington State University, PO Box 644630, Pullman, WA, 99164-4630, United States
| | - Samaneh Tabatabaei
- Department of Chemistry, Washington State University, PO Box 644630, Pullman, WA, 99164-4630, United States
| | - Martin Lochner
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Marc-David Ruepp
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Thomas Jack
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Jonathan Simonin
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Andrew J Thompson
- Pharmacology Department, Cambridge University, Tennis Court Road, Cambridge, CB2 1PD, United Kingdom
| | - Jeffrey P Jones
- Department of Chemistry, Washington State University, PO Box 644630, Pullman, WA, 99164-4630, United States
| | - James A Brozik
- Department of Chemistry, Washington State University, PO Box 644630, Pullman, WA, 99164-4630, United States.
| |
Collapse
|
14
|
Lochner M, Thompson AJ. A review of fluorescent ligands for studying 5-HT3 receptors. Neuropharmacology 2015; 98:31-40. [PMID: 25892507 DOI: 10.1016/j.neuropharm.2015.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 04/01/2015] [Accepted: 04/07/2015] [Indexed: 12/19/2022]
Abstract
The use of fluorescence is a valuable and increasingly accessible means of probing the pharmacology and physiology of cells and their receptors. To date, the use of fluorescence-based methods for 5-HT3 receptor research has been quite limited and, although a variety of approaches have been described, these are broadly distributed throughout the literature. In this review we condense these findings into a single, accessible source of reference with the hope of promoting the use of these valuable molecular probes. This article is part of the Special Issue entitled 'Fluorescent Tools in Neuropharmacology'.
Collapse
Affiliation(s)
- Martin Lochner
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland.
| | - Andrew J Thompson
- Department of Pharmacology, Tennis Court Road, Cambridge, CB2 1PD, UK.
| |
Collapse
|