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Sajkowska JJ, Tsang CH, Kozielewicz P. Application of FRET- and BRET-based live-cell biosensors in deorphanization and ligand discovery studies on orphan G protein-coupled receptors. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2024:100174. [PMID: 39084335 DOI: 10.1016/j.slasd.2024.100174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 07/16/2024] [Accepted: 07/26/2024] [Indexed: 08/02/2024]
Abstract
Bioluminescence- and fluorescence-based resonance energy transfer assays have gained considerable attention in pharmacological research as high-throughput scalable tools applicable to drug discovery. To this end, G protein-coupled receptors represent the biggest target class for marketed drugs, and among them, orphan G protein-coupled receptors have the biggest untapped therapeutic potential. In this review, the cases where biophysical methods, BRET and FRET, were employed for deorphanization and ligand discovery studies on orphan G protein-coupled receptors are listed and discussed.
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Affiliation(s)
- Joanna J Sajkowska
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden; Department of Organic and Physical Chemistry, Faculty of Pharmacy, Medical University of Warsaw, Warsaw, Poland; Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Choi Har Tsang
- Department of Physiology and Pharmacology, Molecular Pharmacology of GPCRs, Karolinska Institute, Stockholm, Sweden
| | - Paweł Kozielewicz
- Department of Physiology and Pharmacology, Molecular Pharmacology of GPCRs, Karolinska Institute, Stockholm, Sweden.
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2
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Baker JG, Summers RJ. Adrenoceptors: Receptors, Ligands and Their Clinical Uses, Molecular Pharmacology and Assays. Handb Exp Pharmacol 2024. [PMID: 38926158 DOI: 10.1007/164_2024_713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
The nine G protein-coupled adrenoceptor subtypes are where the endogenous catecholamines adrenaline and noradrenaline interact with cells. Since they are important therapeutic targets, over a century of effort has been put into developing drugs that modify their activity. This chapter provides an outline of how we have arrived at current knowledge of the receptors, their physiological roles and the methods used to develop ligands. Initial studies in vivo and in vitro with isolated organs and tissues progressed to cell-based techniques and the use of cloned adrenoceptor subtypes together with high-throughput assays that allow close examination of receptors and their signalling pathways. The crystal structures of many of the adrenoceptor subtypes have now been determined opening up new possibilities for drug development.
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Affiliation(s)
- Jillian G Baker
- Cell Signalling, Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, UK.
- Department of Respiratory Medicine, Nottingham University Hospitals NHS Trust, Nottingham, UK.
| | - Roger J Summers
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
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3
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Xu C, Zhou Y, Liu Y, Lin L, Liu P, Wang X, Xu Z, Pin JP, Rondard P, Liu J. Specific pharmacological and G i/o protein responses of some native GPCRs in neurons. Nat Commun 2024; 15:1990. [PMID: 38443355 PMCID: PMC10914727 DOI: 10.1038/s41467-024-46177-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 02/15/2024] [Indexed: 03/07/2024] Open
Abstract
G protein-coupled receptors (GPCRs) constitute the largest family of membrane proteins and are important drug targets. The discovery of drugs targeting these receptors and their G protein signaling properties are based on assays mainly performed with modified receptors expressed in heterologous cells. However, GPCR responses may differ in their native environment. Here, by using highly sensitive Gi/o sensors, we reveal specific properties of Gi/o protein-mediated responses triggered by GABAB, α2 adrenergic and cannabinoid CB1 receptors in primary neurons, different from those in heterologous cells. These include different profiles in the Gi/o protein subtypes-mediated responses, and differences in the potencies of some ligands even at similar receptor expression levels. Altogether, our results show the importance of using biosensors compatible with primary cells for evaluating the activities of endogenous GPCRs in their native environment.
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Affiliation(s)
- Chanjuan Xu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, 510005, Guangzhou, China
| | - Yiwei Zhou
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Kindstar Global Precision Medicine Institute, Wuhan, China
| | - Yuxuan Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Li Lin
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Peng Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaomei Wang
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhengyuan Xu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle (IGF), Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France.
| | - Philippe Rondard
- Institut de Génomique Fonctionnelle (IGF), Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France.
| | - Jianfeng Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China.
- Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, 510005, Guangzhou, China.
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4
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Jobe A, Vijayan R. Orphan G protein-coupled receptors: the ongoing search for a home. Front Pharmacol 2024; 15:1349097. [PMID: 38495099 PMCID: PMC10941346 DOI: 10.3389/fphar.2024.1349097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 02/15/2024] [Indexed: 03/19/2024] Open
Abstract
G protein-coupled receptors (GPCRs) make up the largest receptor superfamily, accounting for 4% of protein-coding genes. Despite the prevalence of such transmembrane receptors, a significant number remain orphans, lacking identified endogenous ligands. Since their conception, the reverse pharmacology approach has been used to characterize such receptors. However, the multifaceted and nuanced nature of GPCR signaling poses a great challenge to their pharmacological elucidation. Considering their therapeutic relevance, the search for native orphan GPCR ligands continues. Despite limited structural input in terms of 3D crystallized structures, with advances in machine-learning approaches, there has been great progress with respect to accurate ligand prediction. Though such an approach proves valuable given that ligand scarcity is the greatest hurdle to orphan GPCR deorphanization, the future pairings of the remaining orphan GPCRs may not necessarily take a one-size-fits-all approach but should be more comprehensive in accounting for numerous nuanced possibilities to cover the full spectrum of GPCR signaling.
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Affiliation(s)
- Amie Jobe
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
- The Big Data Analytics Center, United Arab Emirates University, Al Ain, United Arab Emirates
- Zayed Bin Sultan Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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5
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Duan W, Cao D, Wang S, Cheng J. Serotonin 2A Receptor (5-HT 2AR) Agonists: Psychedelics and Non-Hallucinogenic Analogues as Emerging Antidepressants. Chem Rev 2024; 124:124-163. [PMID: 38033123 DOI: 10.1021/acs.chemrev.3c00375] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Psychedelics make up a group of psychoactive compounds that induce hallucinogenic effects by activating the serotonin 2A receptor (5-HT2AR). Clinical trials have demonstrated the traditional psychedelic substances like psilocybin as a class of rapid-acting and long-lasting antidepressants. However, there is a pressing need for rationally designed 5-HT2AR agonists that possess optimal pharmacological profiles in order to fully reveal the therapeutic potential of these agonists and identify safer drug candidates devoid of hallucinogenic effects. This Perspective provides an overview of the structure-activity relationships of existing 5-HT2AR agonists based on their chemical classifications and discusses recent advancements in understanding their molecular pharmacology at a structural level. The encouraging clinical outcomes of psychedelics in depression treatment have sparked drug discovery endeavors aimed at developing novel 5-HT2AR agonists with improved subtype selectivity and signaling bias properties, which could serve as safer and potentially nonhallucinogenic antidepressants. These efforts can be significantly expedited through the utilization of structure-based methods and functional selectivity-directed screening.
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Affiliation(s)
- Wenwen Duan
- iHuman Institute, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Dongmei Cao
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Sheng Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Jianjun Cheng
- iHuman Institute, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China
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6
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Oligomerization of the heteromeric γ-aminobutyric acid receptor GABA B in a eukaryotic cell-free system. Sci Rep 2022; 12:20742. [PMID: 36456667 PMCID: PMC9715706 DOI: 10.1038/s41598-022-24885-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/22/2022] [Indexed: 12/03/2022] Open
Abstract
Understanding the assembly mechanism and function of membrane proteins is a fundamental problem in biochemical research. Among the membrane proteins, G protein-coupled receptors (GPCRs) represent the largest class in the human body and have long been considered to function as monomers. Nowadays, the oligomeric assembly of GPCRs is widely accepted, although the functional importance and therapeutic intervention remain largely unexplored. This is partly due to difficulties in the heterologous production of membrane proteins. Cell-free protein synthesis (CFPS) with its endogenous endoplasmic reticulum-derived structures has proven as a technique to address this issue. In this study, we investigate for the first time the conceptual CFPS of a heteromeric GPCR, the γ-aminobutyric acid receptor type B (GABAB), from its protomers BR1 and BR2 using a eukaryotic cell-free lysate. Using a fluorescence-based proximity ligation assay, we provide evidence for colocalization and thus suggesting heterodimerization. We prove the heterodimeric assembly by a bioluminescence resonance energy transfer saturation assay providing the manufacturability of a heterodimeric GPCR by CFPS. Additionally, we show the binding of a fluorescent orthosteric antagonist, demonstrating the feasibility of combining the CFPS of GPCRs with pharmacological applications. These results provide a simple and powerful experimental platform for the synthesis of heteromeric GPCRs and open new perspectives for the modelling of protein-protein interactions. Accordingly, the presented technology enables the targeting of protein assemblies as a new interface for pharmacological intervention in disease-relevant dimers.
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Pottie E, Stove CP. In vitro assays for the functional characterization of (psychedelic) substances at the serotonin receptor 5-HT 2A R. J Neurochem 2022; 162:39-59. [PMID: 34978711 DOI: 10.1111/jnc.15570] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/24/2021] [Accepted: 12/29/2021] [Indexed: 12/20/2022]
Abstract
Serotonergic psychedelics are substances that induce alterations in mood, perception, and thought, and have the activation of serotonin (5-HT) 2A receptors (5-HT2A Rs) as a main pharmacological mechanism. Besides their appearance on the (illicit) drug market, e.g. as new psychoactive substances, their potential therapeutic application is increasingly explored. This group of substances demonstrates a broad structural variety, leading to insufficiently described structure-activity relationships, hence illustrating the need for better functional characterization. This review therefore elaborates on the in vitro molecular techniques that have been used the most abundantly for the characterization of (psychedelic) 5-HT2A R agonists. More specifically, this review covers assays to monitor the canonical G protein signaling pathway (e.g. measuring G protein recruitment/activation, inositol phosphate accumulation, or Ca2+ mobilization), assays to monitor non-canonical G protein signaling (such as arachidonic acid release), assays to monitor β-arrestin recruitment or signaling, and assays to monitor receptor conformational changes. In particular, focus lies on the mechanism behind the techniques, and the specific advantages and challenges that are associated with these. Additionally, several variables are discussed that one should consider when attempting to compare functional outcomes from different studies, both linked to the specific assay mechanism and linked to its specific execution, as these may heavily impact the assay outcome.
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Affiliation(s)
- Eline Pottie
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Department of Bioanalysis, Ghent University, Ghent, Belgium
| | - Christophe P Stove
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Department of Bioanalysis, Ghent University, Ghent, Belgium
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8
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Skiba M, Stolwijk JA, Wegener J. Label-free impedance measurements to unravel biomolecular interactions involved in G protein-coupled receptor signaling. Methods Cell Biol 2022; 169:221-236. [DOI: 10.1016/bs.mcb.2021.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Bonaventura J, Lam S, Carlton M, Boehm M, Gomez JL, Solís O, Sánchez-Soto M, Morris PJ, Fredriksson I, Thomas CJ, Sibley DR, Shaham Y, Zarate CA, Michaelides M. Pharmacological and behavioral divergence of ketamine enantiomers: implications for abuse liability. Mol Psychiatry 2021; 26:6704-6722. [PMID: 33859356 PMCID: PMC8517038 DOI: 10.1038/s41380-021-01093-2] [Citation(s) in RCA: 136] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 02/02/2023]
Abstract
Ketamine, a racemic mixture of (S)-ketamine and (R)-ketamine enantiomers, has been used as an anesthetic, analgesic and more recently, as an antidepressant. However, ketamine has known abuse liability (the tendency of a drug to be used in non-medical situations due to its psychoactive effects), which raises concerns for its therapeutic use. (S)-ketamine was recently approved by the United States' FDA for treatment-resistant depression. Recent studies showed that (R)-ketamine has greater efficacy than (S)-ketamine in preclinical models of depression, but its clinical antidepressant efficacy has not been established. The behavioral effects of racemic ketamine have been studied extensively in preclinical models predictive of abuse liability in humans (self-administration and conditioned place preference [CPP]). In contrast, the behavioral effects of each enantiomer in these models are unknown. We show here that in the intravenous drug self-administration model, the gold standard procedure to assess potential abuse liability of drugs in humans, rats self-administered (S)-ketamine but not (R)-ketamine. Subanesthetic, antidepressant-like doses of (S)-ketamine, but not of (R)-ketamine, induced locomotor activity (in an opioid receptor-dependent manner), induced psychomotor sensitization, induced CPP in mice, and selectively increased metabolic activity and dopamine tone in medial prefrontal cortex (mPFC) of rats. Pharmacological screening across thousands of human proteins and at biological targets known to interact with ketamine yielded divergent binding and functional enantiomer profiles, including selective mu and kappa opioid receptor activation by (S)-ketamine in mPFC. Our results demonstrate divergence in the pharmacological, functional, and behavioral effects of ketamine enantiomers, and suggest that racemic ketamine's abuse liability in humans is primarily due to the pharmacological effects of its (S)-enantiomer.
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Affiliation(s)
- Jordi Bonaventura
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, USA.
| | - Sherry Lam
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 21224
| | - Meghan Carlton
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 21224
| | - Matthew Boehm
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 21224
| | - Juan L. Gomez
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 21224
| | - Oscar Solís
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 21224
| | - Marta Sánchez-Soto
- Molecular Neuropharmacology Section, National Institute of Neurological Disorders and Stroke Intramural Research Program, Bethesda, MD, 20892
| | - Patrick J. Morris
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, Rockville, MD, 20850
| | - Ida Fredriksson
- Neurobiology of Relapse Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 212245
| | - Craig J. Thomas
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, Rockville, MD, 20850
| | - David R. Sibley
- Molecular Neuropharmacology Section, National Institute of Neurological Disorders and Stroke Intramural Research Program, Bethesda, MD, 20892
| | - Yavin Shaham
- Neurobiology of Relapse Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, 212245
| | - Carlos A. Zarate
- Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, Intramural Research Program, Bethesda, MD, 20892
| | - Michael Michaelides
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD, USA. .,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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10
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Pharmacological and metabolic characterization of the novel synthetic opioid brorphine and its detection in routine casework. Forensic Sci Int 2021; 327:110989. [PMID: 34509061 DOI: 10.1016/j.forsciint.2021.110989] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/27/2021] [Accepted: 08/29/2021] [Indexed: 11/21/2022]
Abstract
After their first emergence in 2009, Novel synthetic opioids (NSO) have become an emerging class of New Psychoactive Substances (NPS) on the market for these new drugs. So far, 67 NSO have been reported to the Early Warning system of the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA). It is presumed that NSO mainly target the four known opioid receptors, i.e. the μ-opioid (MOR), the δ-opioid (DOR), the κ-opioid (KOR) and nociceptin receptors and that their consumption can result in serious adverse effects such as massive respiratory depression or death. In the present study we investigated the in vivo and in vitro metabolism of brorphine, a NSO that was first identified on the NPS market in August 2019 in the United States, using both a pooled human liver microsome assay and real forensic case samples. For the detection of metabolites LC-HR-MS/MS was used and quantification of brorphine was performed using an LC-MS/MS method. Additionally, we pharmacologically characterized brorphine regarding its activation of the MOR and KOR via G protein recruitment using the [35S]-GTPγS assay. In forensic urine samples, 14 distinct metabolites were identified, whereas in blood only four metabolites could be found. The pooled human liver microsome assay generated six distinct in vitro phase I metabolites. The most prominent in vivo metabolite was formed by N-oxydation, whereas the main in vitro metabolite was formed by hydroxylation. The pharmacological characterization at the MOR and KOR revealed brorphine to be a potent MOR agonist and a weak, partial KOR agonist in the [35S]-GTPγS assay.
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11
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Characterization of dopamine D 2 receptor coupling to G proteins in postmortem brain of subjects with schizophrenia. Pharmacol Rep 2021; 73:1136-1146. [PMID: 34196951 PMCID: PMC8413194 DOI: 10.1007/s43440-021-00305-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/16/2021] [Accepted: 06/24/2021] [Indexed: 11/04/2022]
Abstract
Background Alterations of dopamine D1 (D1R) and D2 receptor (D2R) are proposed in schizophrenia but brain neuroimaging and postmortem studies have shown controversial results in relation to D1R and D2R density. Besides, scarce information on the functionality of brain D1R and D2R is available. The present study characterized G-protein activation by D1R and D2R agonists in postmortem human brain. Furthermore, D2R functional status was compared between schizophrenia and control subjects. Methods G-protein receptor coupling was assessed in control caudate nucleus and frontal cortex by [35S]GTPγS-binding stimulation induced by increasing concentrations (10–10–10–3 M) of dopamine, and the selective dopaminergic agonists SKF38393 (D1R) and NPA (D2R). Concentration–response curves to NPA stimulation of [35S]GTPγS binding were analyzed in antipsychotic-free (n = 10) and antipsychotic-treated (n = 7) schizophrenia subjects and matched controls (n = 17). Results In caudate, [35S]GTPγS-binding responses to agonists were compatible with the existence of functional D2R. In contrast, stimulations in cortex showed responses that did not correspond to D1R or D2R. [35S]GTPγS-binding activation by NPA in caudate displayed biphasic curves with similar profile in schizophrenia (EC50H = 7.94 nM; EC50L = 7.08 μM) and control (EC50H = 7.24 nM; EC50L = 15.14 μM) subjects. The presence or absence of antipsychotic medication did not influence the pharmacological parameters. Conclusions Feasibility of functional evaluation of dopamine receptors in postmortem human brain by conventional [35S]GTPγS-binding assays appears to be restricted to signalling through inhibitory Gi/o proteins. These findings provide functional information about brain D2R status in subjects with schizophrenia and do not support the existence of D2R supersensitive in this mental disorder. Supplementary Information The online version contains supplementary material available at 10.1007/s43440-021-00305-4.
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12
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Grafinger KE, Vandeputte MM, Cannaert A, Ametovski A, Sparkes E, Cairns E, Juchli PO, Haschimi B, Pulver B, Banister SD, Stove CP, Auwärter V. Systematic evaluation of a panel of 30 synthetic cannabinoid receptor agonists structurally related to MMB-4en-PICA, MDMB-4en-PINACA, ADB-4en-PINACA, and MMB-4CN-BUTINACA using a combination of binding and different CB1 receptor activation assays. Part III: The G protein pathway and critical comparison of different assays. Drug Test Anal 2021; 13:1412-1429. [PMID: 33908179 DOI: 10.1002/dta.3054] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 04/20/2021] [Indexed: 01/01/2023]
Abstract
The present work is the last of a three-part study investigating a panel of 30 systematically designed synthetic cannabinoid receptor agonists (SCRAs) including features such as the 4-pentenyl tail and varying head groups including amides and esters of l-valine (MMB, AB), l-tert-leucine (ADB), and l-phenylalanine (APP), as well as adamantyl (A) and cumyl moieties (CUMYL). Here, we evaluated these SCRAs for their capacity to activate the human cannabinoid receptor 1 (CB1 ) via indirect measurement of G protein recruitment. Furthermore, we comparatively evaluated the results obtained from three in vitro assays, based on the recruitment of β-arrestin 2 (βarr2 assay) or Gαi protein (mini-Gαi assay), or binding of [35 S]-GTPγS. The observed efficacies (Emax ) varied depending on the conducted assay. Statistical analysis suggests that the population means of the relative intrinsic activity (RAi ) significantly differ for the [35 S]-GTPγS assay and the other two assays, but the population means of the βarr2 and mini-Gαi assays were not statistically different. Our data suggest that differences observed between the βarr2 and mini-Gαi assays are the best predictor for 'biased agonism' towards βarr or G protein recruitment in our study. SCRAs carrying an ADB or MPP moiety as a head group tended to produce elevated Emax values in the βarr2 assay, which might result in a tendency of these compounds to cause pronounced tolerance in users-a hypothesis that should be evaluated further by future studies. In general, a comparison of efficacies derived from different assays is difficult and should only be conducted very cautiously.
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Affiliation(s)
- Katharina Elisabeth Grafinger
- Institute of Forensic Medicine, Forensic Toxicology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Marthe M Vandeputte
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Annelies Cannaert
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Adam Ametovski
- The Lambert Initiative for Cannabinoid Therapeutics, Brain and Mind Centre, The University of Sydney, Camperdown, NSW, Australia.,School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Eric Sparkes
- The Lambert Initiative for Cannabinoid Therapeutics, Brain and Mind Centre, The University of Sydney, Camperdown, NSW, Australia.,School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Elizabeth Cairns
- The Lambert Initiative for Cannabinoid Therapeutics, Brain and Mind Centre, The University of Sydney, Camperdown, NSW, Australia
| | | | - Belal Haschimi
- Institute of Forensic Medicine, Forensic Toxicology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Hermann Staudinger Graduate School, University of Freiburg, Freiburg, Germany
| | - Benedikt Pulver
- Institute of Forensic Medicine, Forensic Toxicology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Hermann Staudinger Graduate School, University of Freiburg, Freiburg, Germany
| | - Samuel D Banister
- The Lambert Initiative for Cannabinoid Therapeutics, Brain and Mind Centre, The University of Sydney, Camperdown, NSW, Australia.,School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Christophe P Stove
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Volker Auwärter
- Institute of Forensic Medicine, Forensic Toxicology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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13
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Lu S, Jang W, Inoue A, Lambert NA. Constitutive G protein coupling profiles of understudied orphan GPCRs. PLoS One 2021; 16:e0247743. [PMID: 33886554 PMCID: PMC8062009 DOI: 10.1371/journal.pone.0247743] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 03/25/2021] [Indexed: 12/11/2022] Open
Abstract
A large number of GPCRs are potentially valuable drug targets but remain understudied. Many of these lack well-validated activating ligands and are considered “orphan” receptors, and G protein coupling profiles have not been defined for many orphan GPCRs. Here we asked if constitutive receptor activity can be used to determine G protein coupling profiles of orphan GPCRs. We monitored nucleotide-sensitive interactions between 48 understudied orphan GPCRs and five G proteins (240 combinations) using bioluminescence resonance energy transfer (BRET). No receptor ligands were used, but GDP was used as a common G protein ligand to disrupt receptor-G protein complexes. Constitutive BRET between the same receptors and β-arrestins was also measured. We found sufficient GDP-sensitive BRET to generate G protein coupling profiles for 22 of the 48 receptors we studied. Altogether we identified 48 coupled receptor-G protein pairs, many of which have not been described previously. We conclude that receptor-G protein complexes that form spontaneously in the absence of guanine nucleotides can be used to profile G protein coupling of constitutively-active GPCRs. This approach may prove useful for studying G protein coupling of other GPCRs for which activating ligands are not available.
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Affiliation(s)
- Sumin Lu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, Georgia, United States of America
| | - Wonjo Jang
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, Georgia, United States of America
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Nevin A. Lambert
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, Georgia, United States of America
- * E-mail:
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Grönbladh A, Hallberg M. GTPγS-Autoradiography for Studies of Opioid Receptor Functionality. Methods Mol Biol 2021; 2201:109-116. [PMID: 32975793 DOI: 10.1007/978-1-0716-0884-5_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The opioid receptors have been an interesting target for the drug industry for decades. These receptors were pharmacologically characterized in the 1970s and several drugs and peptides have emerged over the years. In 2012, the crystal structures were also demonstrated, with new data on the receptor sites, and thus new possibilities will appear. The role of opioids in the brain has attracted considerable interest in several diseases, especially pain and drug dependence. The opioid receptors are G-protein-coupled receptors (GPCR ) that are Gi coupled which make them suitable for studying the receptor functionality. The [35S]GTP γS autoradiography assay is a good option that has the benefit of generating both anatomical and functional data in the area of interest. It is based on the first step of the signaling mechanism of GPCRs. When a ligand binds to the receptor GTP will replace GDP on the a-subunit of the G-protein, leading to a dissociation of the βγ-subunit. These subunits will start a cascade of second messengers and subsequently a physiological response.
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Affiliation(s)
- Alfhild Grönbladh
- Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Uppsala University, Uppsala, Sweden
| | - Mathias Hallberg
- Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Uppsala University, Uppsala, Sweden.
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15
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Haag F, Ahmed L, Reiss K, Block E, Batista VS, Krautwurst D. Copper-mediated thiol potentiation and mutagenesis-guided modeling suggest a highly conserved copper-binding motif in human OR2M3. Cell Mol Life Sci 2020; 77:2157-2179. [PMID: 31435697 PMCID: PMC7256108 DOI: 10.1007/s00018-019-03279-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 08/07/2019] [Accepted: 08/12/2019] [Indexed: 12/20/2022]
Abstract
Sulfur-containing compounds within a physiological relevant, natural odor space, such as the key food odorants, typically constitute the group of volatiles with the lowest odor thresholds. The observation that certain metals, such as copper, potentiate the smell of sulfur-containing, metal-coordinating odorants led to the hypothesis that their cognate receptors are metalloproteins. However, experimental evidence is sparse-so far, only one human odorant receptor, OR2T11, and a few mouse receptors, have been reported to be activated by sulfur-containing odorants in a copper-dependent way, while the activation of other receptors by sulfur-containing odorants did not depend on the presence of metals. Here we identified an evolutionary conserved putative copper interaction motif CC/CSSH, comprising two copper-binding sites in TMH5 and TMH6, together with the binding pocket for 3-mercapto-2-methylpentan-1-ol in the narrowly tuned human receptor OR2M3. To characterize the copper-binding motif, we combined homology modeling, docking studies, site-directed mutagenesis, and functional expression of recombinant ORs in a cell-based, real-time luminescence assay. Ligand activation of OR2M3 was potentiated in the presence of copper. This effect of copper was mimicked by ionic and colloidal silver. In two broadly tuned receptors, OR1A1 and OR2W1, which did not reveal a putative copper interaction motif, activation by their most potent, sulfur-containing key food odorants did not depend on the presence of copper. Our results suggest a highly conserved putative copper-binding motif to be necessary for a copper-modulated and thiol-specific function of members from three subfamilies of family 2 ORs.
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Affiliation(s)
- Franziska Haag
- Leibniz-Institute for Food Systems Biology, Technical University of Munich, Lise-Meitner-Str. 34, 85354, Freising, Germany
| | - Lucky Ahmed
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Krystle Reiss
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Eric Block
- Department of Chemistry, University at Albany, State University of New York, Albany, NY, 12222, USA
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Dietmar Krautwurst
- Leibniz-Institute for Food Systems Biology, Technical University of Munich, Lise-Meitner-Str. 34, 85354, Freising, Germany.
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16
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Abstract
Proteins are the main source of drug targets and some of them possess therapeutic potential themselves. Among them, membrane proteins constitute approximately 50% of the major drug targets. In the drug discovery pipeline, rapid methods for producing different classes of proteins in a simple manner with high quality are important for structural and functional analysis. Cell-free systems are emerging as an attractive alternative for the production of proteins due to their flexible nature without any cell membrane constraints. In a bioproduction context, open systems based on cell lysates derived from different sources, and with batch-to-batch consistency, have acted as a catalyst for cell-free synthesis of target proteins. Most importantly, proteins can be processed for downstream applications like purification and functional analysis without the necessity of transfection, selection, and expansion of clones. In the last 5 years, there has been an increased availability of new cell-free lysates derived from multiple organisms, and their use for the synthesis of a diverse range of proteins. Despite this progress, major challenges still exist in terms of scalability, cost effectiveness, protein folding, and functionality. In this review, we present an overview of different cell-free systems derived from diverse sources and their application in the production of a wide spectrum of proteins. Further, this article discusses some recent progress in cell-free systems derived from Chinese hamster ovary and Sf21 lysates containing endogenous translocationally active microsomes for the synthesis of membrane proteins. We particularly highlight the usage of internal ribosomal entry site sequences for more efficient protein production, and also the significance of site-specific incorporation of non-canonical amino acids for labeling applications and creation of antibody drug conjugates using cell-free systems. We also discuss strategies to overcome the major challenges involved in commercializing cell-free platforms from a laboratory level for future drug development.
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Affiliation(s)
- Srujan Kumar Dondapati
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476, Potsdam, Germany
| | - Marlitt Stech
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476, Potsdam, Germany
| | - Anne Zemella
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476, Potsdam, Germany
| | - Stefan Kubick
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476, Potsdam, Germany.
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus-Senftenberg, The Brandenburg Medical School Theodor Fontane and the University of Potsdam, Potsdam, Germany.
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Methylation determines the extracellular calcium sensitivity of the leak channel NALCN in hippocampal dentate granule cells. Exp Mol Med 2019; 51:1-14. [PMID: 31601786 PMCID: PMC6802672 DOI: 10.1038/s12276-019-0325-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/18/2019] [Accepted: 07/22/2019] [Indexed: 12/12/2022] Open
Abstract
The sodium leak channel NALCN is a key player in establishing the resting membrane potential (RMP) in neurons and transduces changes in extracellular Ca2+ concentration ([Ca2+]e) into increased neuronal excitability as the downstream effector of calcium-sensing receptor (CaSR). Gain-of-function mutations in the human NALCN gene cause encephalopathy and severe intellectual disability. Thus, understanding the regulatory mechanisms of NALCN is important for both basic and translational research. This study reveals a novel mechanism for NALCN regulation by arginine methylation. Hippocampal dentate granule cells in protein arginine methyltransferase 7 (PRMT7)-deficient mice display a depolarization of the RMP, decreased threshold currents, and increased excitability compared to wild-type neurons. Electrophysiological studies combined with molecular analysis indicate that enhanced NALCN activities contribute to hyperexcitability in PRMT7−/− neurons. PRMT7 depletion in HEK293T cells increases NALCN activity by shifting the dose-response curve of NALCN inhibition by [Ca2+]e without affecting NALCN protein levels. In vitro methylation studies show that PRMT7 methylates a highly conserved Arg1653 of the NALCN gene located in the carboxy-terminal region that is implicated in CaSR-mediated regulation. A kinase-specific phosphorylation site prediction program shows that the adjacent Ser1652 is a potential phosphorylation site. Consistently, our data from site-specific mutants and PKC inhibitors suggest that Arg1653 methylation might modulate Ser1652 phosphorylation mediated by CaSR/PKC-delta, leading to [Ca2+]e-mediated NALCN suppression. Collectively, these data suggest that PRMT7 deficiency decreases NALCN methylation at Arg1653, which, in turn, decreases CaSR/PKC-mediated Ser1652 phosphorylation, lifting NALCN inhibition, thereby enhancing neuronal excitability. Thus, PRMT7-mediated NALCN inhibition provides a potential target for the development of therapeutic tools for neurological diseases. The addition of a methyl group to an arginine residue on the ion channel NALCN contributes to suppress the activity of this membrane protein and reduces neuronal excitability. Hana Cho, Jong-Sun Kang and colleagues at Sungkyunkwan University in South Korea found that neurons in the hippocampus of mice lacking an enzyme that mediates the transfer of methyl groups to proteins have increased NALCN activity and are more likely to fire an electrical signal. Furthermore, they showed that NALCN methylation facilitates the phosphorylation of an adjacent amino acid that prevents channel activation in response to extracellular calcium concentrations. These findings suggest that NALCN methylation has a key role in regulating the channel’s sensitivity to calcium. Moreover, they reveal a new mechanism for regulating neuronal excitability that could be targeted therapeutically to ameliorate diseases characterised by neuronal hyperexcitability.
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Li F, Jiang X, Luo LL, Xu YM, Huang XX, Huang C, Zhang Y. A piggyBac-based TANGO GFP assay for high throughput screening of GPCR ligands in live cells. Cell Commun Signal 2019; 17:49. [PMID: 31122241 PMCID: PMC6533772 DOI: 10.1186/s12964-019-0359-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/01/2019] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND GPCRs are considered essential for various physiological processes and have been the most productive drug targets. Therefore, development of the methods of GPCR ligands screening is a high priority for pharmaceutical industries and research institutions. METHODS We developed a potential method (piggyBac-TANGO) based on the TANGO and PRESTO-TANGO assays. The system was optimized with a piggyBac transposon as a transgene vehicle, and eGFP was used as a reporter instead of luciferase. The assay was validated in the HEK 293T and U87-MG cell lines and antagonist activities of the compounds were assessed. The transgene copy number and long-term stability were evaluated by qPCR. Then, we performed a DRD2-targeted screening for natural products using the piggyBac-TANGO assay. RESULTS The validation assay showed that using the piggyBac transposon as a transgene vehicle produced high signal-to-background ratio and stable readout confirmed by investigation of the transgene copy number and long-term stability. Use of eGFP instead of luciferase as a reporter enabled to create a high throughput system suitable for live cells. Moreover, the piggyBac-TANGO assay permitted versatile detection of antagonist activity of compounds and was not limited to a particular cell type. With the use of the piggyBac-TANGO assay, we have successfully identified a novel agonist of DRD2. CONCLUSION Thus, the results indicate that the piggyBac-TANGO method is a user-friendly, robust and imaging-based assay that provides a novel approach to high throughput GPCR-targeted ligand screening and drug development.
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Affiliation(s)
- Fei Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xi Jiang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Ling-Ling Luo
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Yue-Ming Xu
- iHuman Institute, ShanghaiTech University, Shanghai, China
| | - Xing-Xu Huang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Cheng Huang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Yu Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China.
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19
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Seyedabadi M, Ghahremani MH, Albert PR. Biased signaling of G protein coupled receptors (GPCRs): Molecular determinants of GPCR/transducer selectivity and therapeutic potential. Pharmacol Ther 2019; 200:148-178. [PMID: 31075355 DOI: 10.1016/j.pharmthera.2019.05.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/26/2019] [Indexed: 02/07/2023]
Abstract
G protein coupled receptors (GPCRs) convey signals across membranes via interaction with G proteins. Originally, an individual GPCR was thought to signal through one G protein family, comprising cognate G proteins that mediate canonical receptor signaling. However, several deviations from canonical signaling pathways for GPCRs have been described. It is now clear that GPCRs can engage with multiple G proteins and the line between cognate and non-cognate signaling is increasingly blurred. Furthermore, GPCRs couple to non-G protein transducers, including β-arrestins or other scaffold proteins, to initiate additional signaling cascades. Receptor/transducer selectivity is dictated by agonist-induced receptor conformations as well as by collateral factors. In particular, ligands stabilize distinct receptor conformations to preferentially activate certain pathways, designated 'biased signaling'. In this regard, receptor sequence alignment and mutagenesis have helped to identify key receptor domains for receptor/transducer specificity. Furthermore, molecular structures of GPCRs bound to different ligands or transducers have provided detailed insights into mechanisms of coupling selectivity. However, receptor dimerization, compartmentalization, and trafficking, receptor-transducer-effector stoichiometry, and ligand residence and exposure times can each affect GPCR coupling. Extrinsic factors including cell type or assay conditions can also influence receptor signaling. Understanding these factors may lead to the development of improved biased ligands with the potential to enhance therapeutic benefit, while minimizing adverse effects. In this review, evidence for ligand-specific GPCR signaling toward different transducers or pathways is elaborated. Furthermore, molecular determinants of biased signaling toward these pathways and relevant examples of the potential clinical benefits and pitfalls of biased ligands are discussed.
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Affiliation(s)
- Mohammad Seyedabadi
- Department of Pharmacology, School of Medicine, Bushehr University of Medical Sciences, Iran; Education Development Center, Bushehr University of Medical Sciences, Iran
| | | | - Paul R Albert
- Ottawa Hospital Research Institute, Neuroscience, University of Ottawa, Canada.
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20
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Mancini SJ, Mahmud ZA, Jenkins L, Bolognini D, Newman R, Barnes M, Edye ME, McMahon SB, Tobin AB, Milligan G. On-target and off-target effects of novel orthosteric and allosteric activators of GPR84. Sci Rep 2019; 9:1861. [PMID: 30755705 PMCID: PMC6372602 DOI: 10.1038/s41598-019-38539-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 12/20/2018] [Indexed: 12/03/2022] Open
Abstract
Many members of the G protein-coupled receptor family, including examples with clear therapeutic potential, remain poorly characterised. This often reflects limited availability of suitable tool ligands with which to interrogate receptor function. In the case of GPR84, currently a target for the treatment of idiopathic pulmonary fibrosis, recent times have seen the description of novel orthosteric and allosteric agonists. Using 2-(hexylthiol)pyrimidine-4,6 diol (2-HTP) and di(5,7-difluoro-1H-indole-3-yl)methane (PSB-16671) as exemplars of each class, in cell lines transfected to express either human or mouse GPR84, both ligands acted as effective on-target activators and with high co-operativity in their interactions. This was also the case in lipopolysaccharide-activated model human and mouse immune cell lines. However in mouse bone-marrow-derived neutrophils, where expression of GPR84 is particularly high, the capacity of PSB-16671 but not of 2-HTP to promote G protein activation was predominantly off-target because it was not blocked by an antagonist of GPR84 and was preserved in neutrophils isolated from GPR84 deficient mice. These results illustrate the challenges of attempting to study and define functions of poorly characterised receptors using ligands that have been developed via medicinal chemistry programmes, but where assessed activity has been limited largely to the initially identified target.
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Affiliation(s)
- Sarah J Mancini
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Zobaer Al Mahmud
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Laura Jenkins
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Daniele Bolognini
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Robert Newman
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, CB21 6DG, United Kingdom
| | - Matt Barnes
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, CB21 6DG, United Kingdom
| | - Michelle E Edye
- Wolfson Centre for Age-Related Diseases, King's College London, London, SE1 1UL, United Kingdom
| | - Stephen B McMahon
- Wolfson Centre for Age-Related Diseases, King's College London, London, SE1 1UL, United Kingdom
| | - Andrew B Tobin
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Graeme Milligan
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
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21
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Kumar A, Plückthun A. In vivo assembly and large-scale purification of a GPCR - Gα fusion with Gβγ, and characterization of the active complex. PLoS One 2019; 14:e0210131. [PMID: 30620756 PMCID: PMC6324789 DOI: 10.1371/journal.pone.0210131] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 12/04/2018] [Indexed: 12/13/2022] Open
Abstract
G protein coupled receptors (GPCRs) are central players in recognizing a variety of stimuli to mediate diverse cellular responses. This myriad of functions is accomplished by their modular interactions with downstream intracellular transducers, such as heterotrimeric G proteins and arrestins. Assembling a specific GPCR-G protein pair as a purified complex for their structural and functional investigations remains a challenging task, however, because of the low affinity of the interaction. Here, we optimized fusion constructs of the Gα subunit of the heterotrimeric G protein and engineered versions of rat Neurotensin receptor 1 (NTR1), coexpressed and assembled in vivo with Gβ and Gγ. This was achieved by using the baculovirus-based MultiBac system. We thus generated a functional receptor-G protein fusion complex, which can be efficiently purified using ligand-based affinity chromatography on large scales. Additionally, we utilized a purification method based on a designed ankyrin repeat protein tightly binding to Green Fluorescent Protein (GFP-DARPin) that may be used as a generic approach for a large-scale purification of GPCR-G protein fusion complexes for which no ligands column can be generated. The purification methods described herein will support future studies that aim to understand the structural and functional framework of GPCR activation and signaling.
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Affiliation(s)
- Abhinav Kumar
- Department of Biochemistry, University of Zürich, Zürich, Switzerland
| | - Andreas Plückthun
- Department of Biochemistry, University of Zürich, Zürich, Switzerland
- * E-mail:
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22
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Laschet C, Dupuis N, Hanson J. A dynamic and screening-compatible nanoluciferase-based complementation assay enables profiling of individual GPCR-G protein interactions. J Biol Chem 2018; 294:4079-4090. [PMID: 30593506 DOI: 10.1074/jbc.ra118.006231] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/27/2018] [Indexed: 12/14/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are currently the target of more than 30% of the marketed medicines. However, there is an important medical need for ligands with improved pharmacological activities on validated drug targets. Moreover, most of these ligands remain poorly characterized, notably because of a lack of pharmacological tools. Thus, there is an important demand for innovative assays that can detect and drive the design of compounds with novel or improved pharmacological properties. In particular, a functional and screening-compatible GPCR-G protein interaction assay is still unavailable. Here, we report on a nanoluciferase-based complementation technique to detect ligands that promote a GPCR-G protein interaction. We demonstrate that our system can be used to profile compounds with regard to the G proteins they activate through a given GPCR. Furthermore, we established a proof of applicability of screening for distinct G proteins on dopamine receptor D2 whose differential coupling to Gαi/o family members has been extensively studied. In a D2-Gαi1 versus D2-Gαo screening, we retrieved five agonists that are currently being used in antiparkinsonian medications. We determined that in this assay, piribedil and pergolide are full agonists for the recruitment of Gαi1 but are partial agonists for Gαo, that the agonist activity of ropinirole is biased in favor of Gαi1 recruitment, and that the agonist activity of apomorphine is biased for Gαo We propose that this newly developed assay could be used to develop molecules that selectively modulate a particular G protein pathway.
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Affiliation(s)
- Céline Laschet
- From the Laboratory of Molecular Pharmacology, GIGA-Molecular Biology of Diseases, University of Liège, 4000 Liège and
| | - Nadine Dupuis
- From the Laboratory of Molecular Pharmacology, GIGA-Molecular Biology of Diseases, University of Liège, 4000 Liège and
| | - Julien Hanson
- From the Laboratory of Molecular Pharmacology, GIGA-Molecular Biology of Diseases, University of Liège, 4000 Liège and .,the Laboratory of Medicinal Chemistry, CIRM-Drug Target and Lead Discovery, University of Liège, Liège CHU, B34 (+4), B-4000 Liège, Belgium
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23
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Andrade-Oliva MDLA, Aztatzi-Aguilar OG, García-Sierra F, De Vizcaya-Ruiz A, Arias-Montaño JA. Effect of in vivo exposure to ambient fine particles (PM 2.5) on the density of dopamine D 2-like receptors and dopamine-induced [ 35S]-GTPγS binding in rat prefrontal cortex and striatum membranes. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2018; 60:58-65. [PMID: 29660611 DOI: 10.1016/j.etap.2018.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/28/2018] [Accepted: 04/01/2018] [Indexed: 06/08/2023]
Abstract
Male Sprague-Dawley rats (8-9 weeks-old) were exposed for three days (acute exposure) or eight weeks (subchronic exposure) to purified air or concentrated ambient fine particles, PM2.5 (≤2.5 μm; 15 to 18-fold of ambient air; 370-445 μg/m3). In membranes from rat prefrontal cortex (PFC) or striatum, the density and function of dopamine D2-like receptors (D2Rs) were assessed by [3H]-spiperone binding and dopamine-stimulated [35S]-GTPγS binding, respectively. Glial activation was evaluated by immunoperoxidase labeling of the glial fibrillary acidic protein (GFAP). In the PFC, no significant changes in D2R density or signaling were observed after the acute and subchronic exposure to PM2.5. In the striatum, acute exposure to PM2.5 decreased D2R density, with no effect on signaling efficacy, whereas subchronic exposure did not affect D2R density but reduced signaling efficacy. Both acute and subchronic exposure to PM2.5 induced reactive gliosis in the striatum but not in the PFC. These results indicate that exposure to PM2.5 induces astrocyte activation and alters striatal dopaminergic transmission.
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Affiliation(s)
- María-de-Los-Angeles Andrade-Oliva
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, Av. IPN 2508, Zacatenco, 07360 Ciudad de México, México; Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, Av. IPN 2508, Zacatenco, 07360 Ciudad de México, México
| | - Octavio-Gamaliel Aztatzi-Aguilar
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, Av. IPN 2508, Zacatenco, 07360 Ciudad de México, México
| | - Francisco García-Sierra
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, Av. IPN 2508, Zacatenco, 07360 Ciudad de México, México
| | - Andrea De Vizcaya-Ruiz
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, Av. IPN 2508, Zacatenco, 07360 Ciudad de México, México
| | - José-Antonio Arias-Montaño
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, Av. IPN 2508, Zacatenco, 07360 Ciudad de México, México.
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Ellery J, Dickson L, Cheung T, Ciuclan L, Bunyard P, Mack S, Buffham WJ, Farnaby W, Mitchell P, Brown D, Isaacs R, Barnes M. Identification of compounds acting as negative allosteric modulators of the LPA 1 receptor. Eur J Pharmacol 2018; 833:8-15. [PMID: 29807028 DOI: 10.1016/j.ejphar.2018.05.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 05/24/2018] [Accepted: 05/25/2018] [Indexed: 12/20/2022]
Abstract
The Lysophosphatidic Acid 1 Receptor (LPA1 receptor) has been linked to the initiation and progression of a variety of poorly treated fibrotic conditions. Several compounds that have been described as LPA1 receptor antagonists have progressed into clinical trials: 1-(4-{4-[3-methyl-4-({[(1R)-1-phenylethoxy]carbonyl}amino)-1,2-oxazol-5-yl]phenyl}phenyl)cyclopropane-1-carboxylic acid (BMS-986202) and 2-{4-methoxy-3-[2-(3-methylphenyl)ethoxy]benzamido}-2,3-dihydro-1H-indene-2-carboxylic acid (SAR-100842). We considered that as LPA1 receptor function is involved in many normal physiological processes, inhibition of specific signalling pathways associated with fibrosis may be therapeutically advantageous. We compared the binding and functional effects of a novel compound; 4-({(Cyclopropylmethyl)[4-(2-fluorophenoxy)benzoyl]amino}methyl}benzoic acid (TAK-615) with BMS-986202 and SAR-100842. Back-scattering interferometry (BSI) was used to show that the apparent affinity of TAK-615 was enhanced in the presence of LPA. The binding signal for BMS-986202 was not detected in the presence of LPA suggesting competition but interestingly the apparent affinity of SAR-100842 was also enhanced in the presence of LPA. Only BMS-986202 was able to fully inhibit the response to LPA in calcium mobilisation, β-arrestin, cAMP, GTPγS and RhoA functional assays. TAK-615 and SAR-100842 showed different inhibitory profiles in the same functional assays. Further binding studies indicated that TAK-615 is not competitive with either SAR-100842 or BMS-986202, suggesting a different site of binding. The results generated with this set of experiments demonstrate that TAK-615 acts as a negative allosteric modulator (NAM) of the LPA1 receptor. Surprisingly we find that SAR-100842 also behaves like a NAM. BMS-986202 on the other hand behaves like an orthosteric antagonist.
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Affiliation(s)
- Jonathan Ellery
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK.
| | - Louise Dickson
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Cerevance, 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK.
| | - Toni Cheung
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Cerevance, 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK.
| | - Loredana Ciuclan
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Study Enterprise, Early Clinical Development, IMED Biotech Unit, AstraZeneca, Cambridge, UK.
| | - Peter Bunyard
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Redx Immunology, Block 33, Mereside, Alderley Park, Alderley Edge, Macclesfield SK10 4TG, UK.
| | - Stephen Mack
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Convergence Pharmaceuticals, B900, Babraham Research Campus, Babraham, Cambridgeshire CB22 3AT, UK.
| | - William J Buffham
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Convergence Pharmaceuticals, B900, Babraham Research Campus, Babraham, Cambridgeshire CB22 3AT, UK.
| | - William Farnaby
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
| | - Philip Mitchell
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Charles River Discovery Research Services UK Limited, Robinson Building, Chesterford Research Park, Saffron Walden, Essex CB10 1XL, UK.
| | - Daniel Brown
- Molecular Sensing Inc., 111 10th Ave. S. Suite 110, Nashville, TN, USA; Albany Molecular Research Inc., The Conventus Building, 1001 Main Street, Buffalo, NY 14203, USA.
| | - Richard Isaacs
- Molecular Sensing Inc., 111 10th Ave. S. Suite 110, Nashville, TN, USA; Creoptix Inc., 100 Franklin St Fl7, Boston, MA 02110, USA.
| | - Matt Barnes
- Takeda Cambridge Ltd., 418 Cambridge Science Park, Cambridge, Cambridgeshire CB4 0PZ, UK; Heptares Therapeutics Ltd., BioPark, Broadwater Road, Welwyn Garden City, Hertfordshire AL7 3AX, UK.
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25
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Mastop M, Reinhard NR, Zuconelli CR, Terwey F, Gadella TWJ, van Unen J, Adjobo-Hermans MJW, Goedhart J. A FRET-based biosensor for measuring Gα13 activation in single cells. PLoS One 2018; 13:e0193705. [PMID: 29505611 PMCID: PMC5837189 DOI: 10.1371/journal.pone.0193705] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 02/19/2018] [Indexed: 12/22/2022] Open
Abstract
Förster Resonance Energy Transfer (FRET) provides a way to directly observe the activation of heterotrimeric G-proteins by G-protein coupled receptors (GPCRs). To this end, FRET based biosensors are made, employing heterotrimeric G-protein subunits tagged with fluorescent proteins. These FRET based biosensors complement existing, indirect, ways to observe GPCR activation. Here we report on the insertion of mTurquoise2 at several sites in the human Gα13 subunit, aiming to develop a FRET-based Gα13 activation biosensor. Three fluorescently tagged Gα13 variants were found to be functional based on i) plasma membrane localization and ii) ability to recruit p115-RhoGEF upon activation of the LPA2 receptor. The tagged Gα13 subunits were used as FRET donor and combined with cp173Venus fused to the Gγ2 subunit, as the acceptor. We constructed Gα13 biosensors by generating a single plasmid that produces Gα13-mTurquoise2, Gβ1 and cp173Venus-Gγ2. The Gα13 activation biosensors showed a rapid and robust response when used in primary human endothelial cells that were exposed to thrombin, triggering endogenous protease activated receptors (PARs). This response was efficiently inhibited by the RGS domain of p115-RhoGEF and from the biosensor data we inferred that this is due to GAP activity. Finally, we demonstrated that the Gα13 sensor can be used to dissect heterotrimeric G-protein coupling efficiency in single living cells. We conclude that the Gα13 biosensor is a valuable tool for live-cell measurements that probe spatiotemporal aspects of Gα13 activation.
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Affiliation(s)
- Marieke Mastop
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Nathalie R. Reinhard
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Cristiane R. Zuconelli
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Fenna Terwey
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Theodorus W. J. Gadella
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Jakobus van Unen
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
| | - Merel J. W. Adjobo-Hermans
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Joachim Goedhart
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
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26
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Mahmud ZA, Jenkins L, Ulven T, Labéguère F, Gosmini R, De Vos S, Hudson BD, Tikhonova IG, Milligan G. Three classes of ligands each bind to distinct sites on the orphan G protein-coupled receptor GPR84. Sci Rep 2017; 7:17953. [PMID: 29263400 PMCID: PMC5738391 DOI: 10.1038/s41598-017-18159-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 12/05/2017] [Indexed: 12/18/2022] Open
Abstract
Medium chain fatty acids can activate the pro-inflammatory receptor GPR84 but so also can molecules related to 3,3′-diindolylmethane. 3,3′-Diindolylmethane and decanoic acid acted as strong positive allosteric modulators of the function of each other and analysis showed the affinity of 3,3′-diindolylmethane to be at least 100 fold higher. Methyl decanoate was not an agonist at GPR84. This implies a key role in binding for the carboxylic acid of the fatty acid. Via homology modelling we predicted and confirmed an integral role of arginine172, located in the 2nd extracellular loop, in the action of decanoic acid but not of 3,3′-diindolylmethane. Exemplars from a patented series of GPR84 antagonists were able to block agonist actions of both decanoic acid and 3,3′-diindolylmethane at GPR84. However, although a radiolabelled form of a related antagonist, [3H]G9543, was able to bind with high affinity to GPR84, this was not competed for by increasing concentrations of either decanoic acid or 3,3′-diindolylmethane and was not affected adversely by mutation of arginine172. These studies identify three separable ligand binding sites within GPR84 and suggest that if medium chain fatty acids are true endogenous regulators then co-binding with a positive allosteric modulator would greatly enhance their function in physiological settings.
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Affiliation(s)
- Zobaer Al Mahmud
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, United Kingdom
| | - Laura Jenkins
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, United Kingdom
| | - Trond Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark
| | - Frédéric Labéguère
- Galapagos SASU, 102 Avenue Gaston Roussel, 93230, Romainville, France.,Evotec, 195 Route d'Espagne, 31100, Toulouse, France
| | - Romain Gosmini
- Galapagos SASU, 102 Avenue Gaston Roussel, 93230, Romainville, France
| | - Steve De Vos
- Galapagos NV, Generaal De Wittelaan L11 A3, 2800, Mechelen, Belgium
| | - Brian D Hudson
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, United Kingdom
| | - Irina G Tikhonova
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, BT9 7BL, United Kingdom
| | - Graeme Milligan
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, United Kingdom.
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27
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Emirbayer PE, Sinha A, Ignatchenko V, Hoyer S, Dörrie J, Schaft N, Pischetsrieder M, Kislinger T. Proteomic Response of Human Umbilical Vein Endothelial Cells to Histamine Stimulation. Proteomics 2017; 17. [PMID: 28921918 DOI: 10.1002/pmic.201700116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The histamine receptors (HRs) represent a subclass of G protein-coupled receptors (GPCRs) and comprise four subtypes. Due to their numerous physiological and pathological effects, HRs are popular drug targets for the treatment of allergic reactions or the regulation of gastric acid secretion. Hence, an understanding of the functional selectivity of HR ligands has gained importance. These ligands can bind to specific GPCRs and selectively activate defined pathways. Supporting the activation of a therapeutically necessary pathway without the activation of other signaling cascades can result in drugs with more specific activity and fewer side effects. To evaluate the cellular consequences resulting from receptor binding, comprehensive analyses of cellular protein alterations upon incubation with ligands are required. For this purpose, endothelial cells are treated with histamine, as the endogenous ligand of HRs, to obtain a global overview of its cellular effects. Quantitative proteomics and pathway analyses of histamine-treated and untreated cells reveal enrichment of the nuclear factor-κB and tumor necrosis factor signaling pathways, cytokine-cytokine receptor interactions, complement and coagulation cascades, and acute inflammatory processes upon histamine treatment. This strategy offers the opportunity to monitor HR-mediated signaling in a multidimensional manner.
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Affiliation(s)
- Pelin Esma Emirbayer
- Food Chemistry Unit, Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Ankit Sinha
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | | | - Stefanie Hoyer
- Department of Dermatology, Forschungscampus, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Jan Dörrie
- Department of Dermatology, Forschungscampus, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Niels Schaft
- Department of Dermatology, Forschungscampus, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Monika Pischetsrieder
- Food Chemistry Unit, Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Thomas Kislinger
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
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28
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Eldeeb K, Leone-Kabler S, Howlett AC. Mouse Neuroblastoma CB 1 Cannabinoid Receptor-Stimulated [ 35S]GTPɣS Binding: Total and Antibody-Targeted Gα Protein-Specific Scintillation Proximity Assays. Methods Enzymol 2017; 593:1-21. [PMID: 28750799 PMCID: PMC6535336 DOI: 10.1016/bs.mie.2017.06.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
G protein-coupled receptors (GPCRs) are important regulators of cellular signaling functions and therefore are a major target for drug discovery. The CB1 cannabinoid receptor is among the most highly expressed GPCRs in neurons, where it regulates many differentiated neuronal functions. One model system for studying the biochemistry of neuronal responses is the use of neuroblastoma cells originating from the C1300 tumor in the A/J mouse, including cloned cell lines NS20, N2A, N18TG2, N4TG1, and N1E-115, and various immortalized hybrids of neurons with N18TG2 cells. GPCR signal transduction is mediated through interaction with multiple types and subtypes of G proteins that transduce the receptor stimulus to effectors. The [35S]GTPɣS assay provides a valuable pharmacological method to evaluate efficacy and potency in the first step in GPCR signaling. Here, we present detailed protocols for the [35S]GTPɣS-binding assay to measure the total G protein binding and the antibody-targeted scintillation proximity assay to measure specific Gα proteins in neuroblastoma cell membrane preparations. This chapter presents step-by-step methods from cell culture, membrane preparation, assay procedures, and data analysis.
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Affiliation(s)
- Khalil Eldeeb
- Wake Forest School of Medicine, Winston-Salem, NC, United States; Campbell University School of Osteopathic Medicine, Lillington, NC, United States; AL-Azhar Faculty of Medicine, New Damietta, Egypt.
| | | | - Allyn C Howlett
- Wake Forest School of Medicine, Winston-Salem, NC, United States.
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29
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Vasavda C, Zaccor NW, Scherer PC, Sumner CJ, Snyder SH. Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding. J Vis Exp 2017. [PMID: 28654029 DOI: 10.3791/55561] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
G-Protein-Coupled Receptors (GPCRs) are a large family of transmembrane receptors that play critical roles in normal cellular physiology and constitute a major pharmacological target for multiple indications, including analgesia, blood pressure regulation, and the treatment of psychiatric disease. Upon ligand binding, GPCRs catalyze the activation of intracellular G-proteins by stimulating the incorporation of guanosine triphosphate (GTP). Activated G-proteins then stimulate signaling pathways that elicit cellular responses. GPCR signaling can be monitored by measuring the incorporation of a radiolabeled and non-hydrolyzable form of GTP, [35S]guanosine-5'-O-(3-thio)triphosphate ([35S]GTPγS), into G-proteins. Unlike other methods that assess more downstream signaling processes, [35S]GTPγS binding measures a proximal event in GPCR signaling and, importantly, can distinguish agonists, antagonists, and inverse agonists. The present protocol outlines a sensitive and specific method for studying GPCR signaling using crude membrane preparations of an archetypal GPCR, the µ-opioid receptor (MOR1). Although alternative approaches to fractionate cells and tissues exist, many are cost-prohibitive, tedious, and/or require non-standard laboratory equipment. The present method provides a simple procedure that enriches functional crude membranes. After isolating MOR1, various pharmacological properties of its agonist, [D-Ala, N-MePhe, Gly-ol]-enkephalin (DAMGO), and antagonist, naloxone, were determined.
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Affiliation(s)
- Chirag Vasavda
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine
| | - Nicholas W Zaccor
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine
| | - Paul C Scherer
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine
| | - Charlotte J Sumner
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine; Department of Neurology and neurosurgery, Johns Hopkins University School of Medicine
| | - Solomon H Snyder
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine; Departments of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine;
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30
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Storch U, Straub J, Erdogmus S, Gudermann T, Mederos Y Schnitzler M. Dynamic monitoring of G i/o-protein-mediated decreases of intracellular cAMP by FRET-based Epac sensors. Pflugers Arch 2017; 469:725-737. [PMID: 28386636 PMCID: PMC5438440 DOI: 10.1007/s00424-017-1975-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 03/25/2017] [Accepted: 03/30/2017] [Indexed: 01/17/2023]
Abstract
Analysis of G-protein-coupled receptor (GPCR) signaling, in particular of the second messenger cAMP that is tightly controlled by Gs- and Gi/o-proteins, is a central issue in biomedical research. The classical biochemical method to monitor increases in intracellular cAMP concentrations consists of a radioactive multicellular assay, which is well established, highly sensitive, and reproducible, but precludes continuous spatial and temporal assessment of cAMP levels in single living cells. For this purpose, Förster resonance energy transfer (FRET)-based Epac cAMP sensors are well suitable. So far, the latter sensors have been employed to monitor Gs-induced cAMP increases and it has remained elusive whether Epac sensors can reliably detect decreased intracellular cAMP levels as well. In this study, we systematically optimize experimental strategies employing FRET-based cAMP sensors to monitor Gi/o-mediated cAMP reductions. FRET experiments with adrenergic α2A or μ opioid receptors and a set of different Epac sensors allowed for time-resolved, valid, and reliable detection of cAMP level decreases upon Gi/o-coupled receptor activation in single living cells, and this effect can be reversed by selective receptor antagonists. Moreover, pre-treatment with forskolin or 3-isobutyl-1-methylxanthine (IBMX) to artificially increase basal cAMP levels was not required to monitor Gi/o-coupled receptor activation. Thus, using FRET-based cAMP sensors is of major advantage when compared to classical biochemical and multi-cellular assays.
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Affiliation(s)
- Ursula Storch
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University of Munich, Goethestr. 33, 80336, Munich, Germany
| | - Julie Straub
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University of Munich, Goethestr. 33, 80336, Munich, Germany
| | - Serap Erdogmus
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University of Munich, Goethestr. 33, 80336, Munich, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University of Munich, Goethestr. 33, 80336, Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Munich Heart Alliance, Munich, Germany.,Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research, Munich, Germany
| | - Michael Mederos Y Schnitzler
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University of Munich, Goethestr. 33, 80336, Munich, Germany. .,DZHK (German Centre for Cardiovascular Research), Munich Heart Alliance, Munich, Germany.
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31
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Trans DJ, Bai R, Addison JB, Liu R, Hamel E, Coleman MA, Henderson PT. Synthesis of two fluorescent GTPγS molecules and their biological relevance. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2017; 36:379-391. [PMID: 28282254 DOI: 10.1080/15257770.2016.1231320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Fluorescent GTP analogues are utilized for an assortment of nucleic acid and protein characterization studies. Non-hydrolysable analogues such as GTPγS offer the advantage of keeping proteins in a GTP-bound conformation due to their resistance to hydrolysis into GDP. Two novel fluorescent GTPγS molecules were developed by linking fluorescein and tetramethylrhodamine to the γ-thiophosphate of GTPγS. Chemical and biological analysis of these two compounds revealed their successful synthesis and ability to bind to the nucleotide-binding site of tubulin. These two new fluorescent non-hydrolysable nucleotides offer new possibilities for biophysical and biochemical characterization of GTP-binding proteins.
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Affiliation(s)
- Denise J Trans
- a Department of Internal Medicine and UC Davis Comprehensive Cancer Center , University of California , Davis , CA , USA
| | - Ruoli Bai
- b Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, Frederick National Laboratory for Cancer Research , National Institutes of Health , Frederick , MD , USA
| | - J Bennet Addison
- c Nuclear Magnetic Resonance Facility , University of California , Davis , CA , USA
| | - Ruiwu Liu
- d Department of Biochemistry and Molecular Medicine , University of California , Davis , CA , USA
| | - Ernest Hamel
- b Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, Frederick National Laboratory for Cancer Research , National Institutes of Health , Frederick , MD , USA
| | - Matthew A Coleman
- e Department of Radiation Oncology , University of California , Davis , CA , USA.,f Lawrence Livermore National Laboratory , Livermore , CA , USA
| | - Paul T Henderson
- a Department of Internal Medicine and UC Davis Comprehensive Cancer Center , University of California , Davis , CA , USA
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32
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Hot B, Valnohova J, Arthofer E, Simon K, Shin J, Uhlén M, Kostenis E, Mulder J, Schulte G. FZD 10-Gα 13 signalling axis points to a role of FZD 10 in CNS angiogenesis. Cell Signal 2017; 32:93-103. [PMID: 28126591 DOI: 10.1016/j.cellsig.2017.01.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/09/2017] [Accepted: 01/21/2017] [Indexed: 12/20/2022]
Abstract
Among the 10 Frizzled (FZD) isoforms belonging to the Class F of G protein-coupled receptors (GPCRs), FZD10 remains the most enigmatic. FZD10 shows homology to FZD4 and FZD9 and was previously implicated in both β-catenin-dependent and -independent signalling. In normal tissue, FZD10 levels are generally very low; however, its upregulation in synovial carcinoma has attracted some attention for therapy. Our findings identify FZD10 as a receptor interacting with and signalling through the heterotrimeric G protein Gα13 but not Gα12, Gαi1, GαoA, Gαs, or Gαq. Stimulation with the FZD agonist WNT induced the dissociation of the Gα13 protein from FZD10, and led to global Gα12/13-dependent cell changes assessed by dynamic mass redistribution measurements. Furthermore, we show that FZD10 mediates Gα12/13 activation-dependent induction of YAP/TAZ transcriptional activity. In addition, we show a distinct expression of FZD10 in embryonic CNS endothelial cells at E11.5-E14.5. Given the well-known importance of Gα13 signalling for the development of the vascular system, the selective expression of FZD10 in brain vascular endothelial cells points at a potential role of FZD10-Gα13 signalling in CNS angiogenesis.
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Affiliation(s)
- Belma Hot
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S17177 Stockholm, Sweden
| | - Jana Valnohova
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S17177 Stockholm, Sweden
| | - Elisa Arthofer
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S17177 Stockholm, Sweden; Section on Molecular Signal Transduction Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 35A Convent Drive, MSC 3752, Bethesda, MD 20892-3752, USA
| | - Katharina Simon
- Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Bonn, Germany
| | - Jaekyung Shin
- Science for Life Laboratory, Department of Neuroscience, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | - Mathias Uhlén
- Science for Life Laboratory, KTH-Royal Institute of Technology, SE-17121 Stockholm, Sweden
| | - Evi Kostenis
- Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Bonn, Germany
| | - Jan Mulder
- Science for Life Laboratory, Department of Neuroscience, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | - Gunnar Schulte
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S17177 Stockholm, Sweden; Faculty of Science, Institute of Experimental Biology, Masaryk University, Brno, Czech Republic.
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33
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Tang W, Huang B, Wang J, An L, Zhong H, Yang H, Li P, Chen J. A label-free screening approach targeted protease-activated receptor 1 based on dynamic mass redistribution in living cells. RSC Adv 2017. [DOI: 10.1039/c7ra07927c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Protease-activated receptor 1 (PAR-1) antagonists strongly inhibit thrombin-induced platelet aggregation and are proved to be effective as anti-thrombotic drugs.
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Affiliation(s)
- Weiwei Tang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Bixia Huang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Jiancheng Wang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Lin An
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | | | - Hua Yang
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Ping Li
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
| | - Jun Chen
- State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- P. R. China
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Hur W, Rosen H, Gray NS. A benzo[ b ]thiophene-based selective type 4 S1P receptor agonist. Bioorg Med Chem Lett 2017; 27:1-5. [DOI: 10.1016/j.bmcl.2016.11.050] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 11/17/2016] [Indexed: 11/15/2022]
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Seemann WK, Wenzel D, Schrage R, Etscheid J, Bödefeld T, Bartol A, Warnken M, Sasse P, Klöckner J, Holzgrabe U, DeAmici M, Schlicker E, Racké K, Kostenis E, Meyer R, Fleischmann BK, Mohr K. Engineered Context-Sensitive Agonism: Tissue-Selective Drug Signaling through a G Protein-Coupled Receptor. J Pharmacol Exp Ther 2016; 360:289-299. [PMID: 28082514 DOI: 10.1124/jpet.116.237149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 11/10/2016] [Indexed: 11/22/2022] Open
Abstract
Drug discovery strives for selective ligands to achieve targeted modulation of tissue function. Here we introduce engineered context-sensitive agonism as a postreceptor mechanism for tissue-selective drug action through a G protein-coupled receptor. Acetylcholine M2-receptor activation is known to mediate, among other actions, potentially dangerous slowing of the heart rate. This unwanted side effect is one of the main reasons that limit clinical application of muscarinic agonists. Herein we show that dualsteric (orthosteric/allosteric) agonists induce less cardiac depression ex vivo and in vivo than conventional full agonists. Exploration of the underlying mechanism in living cells employing cellular dynamic mass redistribution identified context-sensitive agonism of these dualsteric agonists. They translate elevation of intracellular cAMP into a switch from full to partial agonism. Designed context-sensitive agonism opens an avenue toward postreceptor pharmacologic selectivity, which even works in target tissues operated by the same subtype of pharmacologic receptor.
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Affiliation(s)
- Wiebke K Seemann
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Daniela Wenzel
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Ramona Schrage
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Justine Etscheid
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Theresa Bödefeld
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Anna Bartol
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Mareille Warnken
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Philipp Sasse
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Jessica Klöckner
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Ulrike Holzgrabe
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Marco DeAmici
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Eberhard Schlicker
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Kurt Racké
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Evi Kostenis
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Rainer Meyer
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Bernd K Fleischmann
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
| | - Klaus Mohr
- Pharmacology and Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany (W.K.S., R.S., J.E., T.B., A.B., K.M.); Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, Bonn, Germany (D.W., P.S., B.K.F.); Institute of Pharmacology & Toxicology, University of Bonn, Bonn, Germany (M.W., E.S., K.R.); Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Würzburg, Würzburg, Germany (J.K., U.H.); Dipartimento di Scienze Farmaceutiche, Sezione di Chimica Farmaceutica 'Pietro Pratesi,' Università degli Studi di Milano, Milano, Italy (M.D.); Molecular, Cellular, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany (E.K.); Institute of Physiology II, University of Bonn, Bonn, Germany (R.M.); Center of Pharmacology, University of Cologne, Cologne, Germany (W.K.S.)
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Cannaert A, Storme J, Franz F, Auwärter V, Stove CP. Detection and Activity Profiling of Synthetic Cannabinoids and Their Metabolites with a Newly Developed Bioassay. Anal Chem 2016; 88:11476-11485. [DOI: 10.1021/acs.analchem.6b02600] [Citation(s) in RCA: 160] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Annelies Cannaert
- Laboratory
of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical
Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Jolien Storme
- Laboratory
of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical
Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Florian Franz
- Institute
of Forensic Medicine, Forensic Toxicology, Medical Center −
University of Freiburg, Faculty of Medicine, University of Freiburg, Albertstr. 9, 79104 Freiburg, Germany
| | - Volker Auwärter
- Institute
of Forensic Medicine, Forensic Toxicology, Medical Center −
University of Freiburg, Faculty of Medicine, University of Freiburg, Albertstr. 9, 79104 Freiburg, Germany
| | - Christophe P. Stove
- Laboratory
of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical
Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
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Noël F, do Monte FM. Validation of a Na +-shift binding assay for estimation of the intrinsic efficacy of ligands at the A 2A adenosine receptor. J Pharmacol Toxicol Methods 2016; 84:51-56. [PMID: 27810394 DOI: 10.1016/j.vascn.2016.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 10/27/2016] [Accepted: 10/30/2016] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Determination of the intrinsic efficacy of ligands at the A2A receptor is important for selecting drug candidates, e.g. in the case of inflammatory diseases where agonists are searched for or in Parkinson disease (antagonists). METHODS Three functional binding assays were compared with up to seven ligands with different efficacies: the GTP-shift method based on the decrease of affinity observed with agonists when GTP is added to the competition binding assay; the Ki ratio method based on the different affinity states of the receptor when using an agonist or antagonist radioligand and the Na+-shift assay based on the difference of affinity of agonists when tested in a medium containing a divalent cation (50mM MgCl2) favoring the G protein coupled agonist-receptor complex or sodium (100mM NaCl) as negative allosteric modulator. RESULTS The Na+-shift assay proposed herein successfully discriminated the full agonists CGS21680, NECA and adenosine (IC50 ratio=13-14) from the weak inverse agonists ZM241385 and IBMX (IC50 ratio=0.85) and the partial agonists LUF5834 and regadenoson (IC50 ratios equal to 3 and 10, respectively). DISCUSSION We conclude that the Na+-shift assay proposed herein for the A2A receptors has been validated and represents a rapid, economic and efficient functional binding assay to be used in a drug development program for early estimation of the intrinsic efficacy of hits.
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Affiliation(s)
- François Noël
- Laboratório de Farmacologia Bioquímica e Molecular, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil.
| | - Fernando M do Monte
- Laboratório de Farmacologia Bioquímica e Molecular, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil
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Bolognini D, Moss CE, Nilsson K, Petersson AU, Donnelly I, Sergeev E, König GM, Kostenis E, Kurowska-Stolarska M, Miller A, Dekker N, Tobin AB, Milligan G. A Novel Allosteric Activator of Free Fatty Acid 2 Receptor Displays Unique Gi-functional Bias. J Biol Chem 2016; 291:18915-31. [PMID: 27385588 PMCID: PMC5009265 DOI: 10.1074/jbc.m116.736157] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Indexed: 01/07/2023] Open
Abstract
The short chain fatty acid receptor FFA2 is able to stimulate signaling via both Gi- and Gq/G11-promoted pathways. These pathways are believed to control distinct physiological end points but FFA2 receptor ligands appropriate to test this hypothesis have been lacking. Herein, we characterize AZ1729, a novel FFA2 regulator that acts as a direct allosteric agonist and as a positive allosteric modulator, increasing the activity of the endogenously produced short chain fatty acid propionate in Gi-mediated pathways, but not at those transduced by Gq/G11. Using AZ1729 in combination with direct inhibitors of Gi and Gq/G11 family G proteins demonstrated that although both arms contribute to propionate-mediated regulation of phospho-ERK1/2 MAP kinase signaling in FFA2-expressing 293 cells, the Gq/G11-mediated pathway is predominant. We extend these studies by employing AZ1729 to dissect physiological FFA2 signaling pathways. The capacity of AZ1729 to act at FFA2 receptors to inhibit β-adrenoreceptor agonist-promoted lipolysis in primary mouse adipocytes and to promote chemotaxis of isolated human neutrophils confirmed these as FFA2 processes mediated by Gi signaling, whereas, in concert with blockade by the Gq/G11 inhibitor FR900359, the inability of AZ1729 to mimic or regulate propionate-mediated release of GLP-1 from mouse colonic preparations defined this physiological response as an end point transduced via activation of Gq/G11.
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Affiliation(s)
- Daniele Bolognini
- From the Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Catherine E Moss
- From the Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom, the Medical Research Council Toxicology Unit, University of Leicester, Leicester LE1 9HN, United Kingdom
| | | | - Annika U Petersson
- Respiratory, Inflammatory and Autoimmune Diseases Innovative Medicines and Early Development Biotech Unit, Department of Medicinal Chemistry, and
| | - Iona Donnelly
- the Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Eugenia Sergeev
- From the Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Gabriele M König
- Institute of Pharmaceutical Biology, University of Bonn, 53115 Bonn, Germany, and
| | - Evi Kostenis
- the Molecular, Cellular and Pharmacobiology Section
| | - Mariola Kurowska-Stolarska
- the Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Ashley Miller
- the Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Niek Dekker
- the Discovery Sciences, Reagents and Assay Development, AstraZeneca, Mölndal, Pepparedsleden 1, SE-431 83, Mölndal, Sweden
| | - Andrew B Tobin
- From the Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom, the Medical Research Council Toxicology Unit, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Graeme Milligan
- From the Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom,
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Eldeeb K, Leone-Kabler S, Howlett AC. CB1 cannabinoid receptor-mediated increases in cyclic AMP accumulation are correlated with reduced Gi/o function. J Basic Clin Physiol Pharmacol 2016; 27:311-22. [PMID: 27089415 PMCID: PMC5497837 DOI: 10.1515/jbcpp-2015-0096] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 03/10/2016] [Indexed: 04/20/2023]
Abstract
BACKGROUND CB1 cannabinoid receptors (CB1Rs) stimulate Gi/o-dependent signaling pathways. CB1R-mediated cAMP increases were proposed to result from Gs activation, but CB1R-stimulated GTPγS binding to Gs has not heretofore been investigated. METHODS Three models of CB1R-stimulated cAMP production were tested: pertussis toxin disruption of Gi/o in N18TG2 cells; L341A/A342L-CB1R expressed in Chinese hamster ovary (CHO) cells; and CB1 and D2 dopamine receptors endogenously co-expressed in MN9D cells. cAMP was assayed by [3H]cAMP binding competition. G protein activation was assayed by the antibody-targeted scintillation proximity assay. RESULTS In L341A/A342L-CB1-CHO cells, cannabinoid agonists significantly stimulated cAMP accumulation over vehicle; (-)-3-[2-hydroxyl-4-(1,1-dimethylheptyl)phenyl]-4-[3-hydroxyl propyl] cyclohexan-1-ol (CP55940)-stimulated [35S]GTPγS binding to Gi1/2/3 was reversed, whereas binding to Gs was not different from CB1R. In MN9D cells, CB1 agonist HU210 or D2 agonist quinpirole alone inhibited forskolin-activated cAMP accumulation, whereas HU210 plus quinpirole increased cAMP accumulation above basal. HU210 alone stimulated [35S]GTPγS binding to Gi1/2/3, whereas co-stimulation with quinpirole reversed HU210-stimulated [35S]GTPγS binding to Gi1/2/3. CONCLUSIONS CB1R couples to Gs but with low efficacy compared to Gi/o. The L341A/A342L mutation in CB1R reversed CP55940 activation of Gi to an inhibition, but had no effect on Gs. Combined CB1 plus D2 agonists in MN9D cells converted the CB1 agonist-mediated activation of Gi to inhibition of Gi. In these models, the CB1 agonist response was converted to an inverse agonist response at Gi activation. Cannabinoid agonist-stimulated cAMP accumulation can be best explained as reduced activation of Gi, thereby attenuating the tonic inhibitory influence of Gi on the major isoforms of adenylyl cyclase.
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Affiliation(s)
- Khalil Eldeeb
- Dept. Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
- ALAzhar Faculty of Medicine, New Damietta, Egypt
- Dept Pharmacology, Campbell School of Osteopathic Medicine, Buies Creek, NC 27506, USA
| | - Sandra Leone-Kabler
- Dept. Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Allyn C. Howlett
- Dept. Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
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Sergeev E, Hansen AH, Pandey SK, MacKenzie AE, Hudson BD, Ulven T, Milligan G. Non-equivalence of Key Positively Charged Residues of the Free Fatty Acid 2 Receptor in the Recognition and Function of Agonist Versus Antagonist Ligands. J Biol Chem 2015; 291:303-17. [PMID: 26518871 PMCID: PMC4697166 DOI: 10.1074/jbc.m115.687939] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Indexed: 01/22/2023] Open
Abstract
Short chain fatty acids (SCFAs) are produced in the gut by bacterial fermentation of poorly digested carbohydrates. A key mediator of their actions is the G protein-coupled free fatty acid 2 (FFA2) receptor, and this has been suggested as a therapeutic target for the treatment of both metabolic and inflammatory diseases. However, a lack of understanding of the molecular determinants dictating how ligands bind to this receptor has hindered development. We have developed a novel radiolabeled FFA2 antagonist to probe ligand binding to FFA2, and in combination with mutagenesis and molecular modeling studies, we define how agonist and antagonist ligands interact with the receptor. Although both agonist and antagonist ligands contain negatively charged carboxylates that interact with two key positively charged arginine residues in transmembrane domains V and VII of FFA2, there are clear differences in how these interactions occur. Specifically, although agonists require interaction with both arginine residues to bind the receptor, antagonists require an interaction with only one of the two. Moreover, different chemical series of antagonist interact preferentially with different arginine residues. A homology model capable of rationalizing these observations was developed and provides a tool that will be invaluable for identifying improved FFA2 agonists and antagonists to further define function and therapeutic opportunities of this receptor.
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Affiliation(s)
- Eugenia Sergeev
- From the Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom and
| | - Anders Højgaard Hansen
- the Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Sunil K Pandey
- the Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Amanda E MacKenzie
- From the Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom and
| | - Brian D Hudson
- From the Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom and
| | - Trond Ulven
- the Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Graeme Milligan
- From the Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom and
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Schrage R, De Min A, Hochheiser K, Kostenis E, Mohr K. Superagonism at G protein-coupled receptors and beyond. Br J Pharmacol 2015; 173:3018-27. [PMID: 26276510 DOI: 10.1111/bph.13278] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/01/2015] [Accepted: 08/08/2015] [Indexed: 12/18/2022] Open
Abstract
Ligands targeting GPCRs can be categorized according to their intrinsic efficacy to trigger a specific, receptor-mediated response. A ligand endowed with the same level of efficacy as the endogenous agonist can be classified as a full agonist, whereas a compound that displays greater efficacy, that is, higher receptor signalling output than the endogenous agonist, can be called a superagonist. Subsequent to GPCR activation, an intracellular signalling cascade is set in motion, which may generate substantial amplification of the signal. This may obscure superagonism in pharmacological assays and, therefore, the definition of superagonism necessitates a combination of operational approaches, reduction of spare receptors or estimation of receptor activation close to the receptor level to quantify relative agonist efficacies in a particular system. The first part of this review will compare GPCR superagonism with superagonism in the field of immunology, where this term is well established. In the second part, known GPCR superagonists will be reviewed. Then, the experimental and analytical challenges in the deconvolution of GPCR superagonism will be addressed. Finally, the potential benefit of superagonism is discussed. The molecular mechanisms behind GPCR superagonism are not completely understood. However, crystallography shows that agonist binding alone is not sufficient for a fully active receptor state and that binding of the G protein is at least equally important. Accordingly, the emerging number of reported superagonists implies that ligand-induced receptor conformations more active than the ones stabilized by the endogenous agonist are indeed feasible. Superagonists may have therapeutic potential when receptor function is impaired or to induce negative feedback mechanisms. Linked Articles This article is part of a themed section on Molecular Pharmacology of G Protein-Coupled Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.20/issuetoc.
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Affiliation(s)
- R Schrage
- Pharmacology & Toxicology Section, Institute of Pharmacy, University of Bonn, 53121, Bonn, Germany.
| | - A De Min
- Pharmacology & Toxicology Section, Institute of Pharmacy, University of Bonn, 53121, Bonn, Germany
| | - K Hochheiser
- Peter Doherty Institute, Department of Microbiology and Immunology, University of Melbourne, Melbourne, VIC, 3100, Australia
| | - E Kostenis
- Molecular-, Cellular-, and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, 53115, Bonn, Germany
| | - K Mohr
- Pharmacology & Toxicology Section, Institute of Pharmacy, University of Bonn, 53121, Bonn, Germany
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Grönbladh A, Hallberg M. [(35)S]GTPγS autoradiography for studies of opioid receptor functionality. Methods Mol Biol 2015; 1230:169-76. [PMID: 25293324 DOI: 10.1007/978-1-4939-1708-2_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The opioid receptors have been an interesting target for the drug industry for decades. These receptors were pharmacologically characterized in the 1970s and several drugs and peptides have emerged over the years. In 2012, the crystal structures were also demonstrated, with new data on the receptor sites, and thus new possibilities will appear. The role of opioids in the brain has attracted considerable interest in several diseases, especially pain and drug dependence. The opioid receptors are G-protein-coupled receptors (GPCR) that are Gi-coupled which make them suitable for studying the receptor functionality. The [(35)S]GTPγS autoradiography assay is a good option that has the benefit of generating both anatomical and functional data in the area of interest. It is based on the first step of the signaling mechanism of GPCRs. When a ligand binds to the receptor GTP will replace GDP on the α-subunit of the G protein, leading to a dissociation of the βγ-subunit. These subunits will start a cascade of second messengers and subsequently a physiological response.
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Affiliation(s)
- Alfhild Grönbladh
- Division of Biological Research on Drug Dependence, Department of Pharmaceutical Biosciences, Beijer Laboratory, Uppsala University, 591, Uppsala, 751 24, Sweden
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Brejchová J, Sýkora J, Ostašov P, Merta L, Roubalová L, Janáček J, Hof M, Svoboda P. TRH-receptor mobility and function in intact and cholesterol-depleted plasma membrane of HEK293 cells stably expressing TRH-R-eGFP. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:781-96. [DOI: 10.1016/j.bbamem.2014.11.029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 11/24/2014] [Accepted: 11/26/2014] [Indexed: 01/03/2023]
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Hamamoto A, Kobayashi Y, Saito Y. Identification of amino acids that are selectively involved in Gi/o activation by rat melanin-concentrating hormone receptor 1. Cell Signal 2015; 27:818-27. [PMID: 25617691 DOI: 10.1016/j.cellsig.2015.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 12/30/2014] [Accepted: 01/14/2015] [Indexed: 02/01/2023]
Abstract
Many G-protein-coupled receptors (GPCRs) are known to functionally couple to multiple G-protein subfamily members. Although promiscuous G-protein coupling enables GPCRs to mediate diverse signals, only a few GPCRs have been identified with differential determinants for coupling to distinct Gα proteins. Mammalian melanin-concentrating hormone receptor 1 (MCHR1) couples to dual G-protein subfamilies. However, the selectivity mechanisms between MCHR1 and different subtypes of Gα proteins are unclear. Our previous studies demonstrated that mammalian MCHR1 couples to both Gi/o and Gq, whereas goldfish MCHR1 exclusively couples to Gq. In this study, we analyzed multiple sequence alignments between rat and goldfish MCHR1s, and designed three multisubstituted mutants of rat MCHR1 by replacing corresponding residues with those in goldfish MCHR1, focusing on regions around the cytosolic intracellular loops. By measurement of intracellular Ca(2+) mobilization, we found that two MCHR1 mutants, i2_6sub and i3_6sub, which contained six simultaneously substituted residues in the second intracellular loop or a combination of substituted residues in the third intracellular loop and fifth transmembrane domain, respectively, significantly reduced Gi/o-sensitive pertussis toxin responsiveness without altering Gq-mediated activity. Analyses of 10 other substitutions revealed that the multiple substitutions in i2_6sub and i3_6sub were necessary for Gi/o-selective responses. As judged by Gi/o-dependent GTPγS binding and cyclic AMP assays, i2_6sub and i3_6sub elicited phenotypes for impaired Gi/o-mediated signaling. We also monitored the dynamic mass redistribution (DMR) in living cells, which reveals receptor activity as an optical trace containing activation of all GPCR coupling classes. Cells transfected with i2_6sub or i3_6sub exhibited reduced Gi/o-mediated DMR responses compared with those transfected with MCHR1. These data suggest that two different regions independently affect the Gi/o-protein preference, and that multiple residues comprise a conformation favoring Gi/o-protein coupling and subsequently result in Gi/o-selective signaling.
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Affiliation(s)
- Akie Hamamoto
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | - Yuki Kobayashi
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | - Yumiko Saito
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan.
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Schrage R, Seemann WK, Klöckner J, Dallanoce C, Racké K, Kostenis E, De Amici M, Holzgrabe U, Mohr K. Agonists with supraphysiological efficacy at the muscarinic M2 ACh receptor. Br J Pharmacol 2014; 169:357-70. [PMID: 23062057 DOI: 10.1111/bph.12003] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 09/18/2012] [Accepted: 09/19/2012] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Artificial agonists may have higher efficacy for receptor activation than the physiological agonist. Until now, such 'superagonism' has rarely been reported for GPCRs. Iperoxo is an extremely potent muscarinic receptor agonist. We hypothesized that iperoxo is a 'superagonist'. EXPERIMENTAL APPROACH Signalling of iperoxo and newly synthesized structural analogues was compared with that of ACh at label-free M2 muscarinic receptors applying whole cell dynamic mass redistribution, measurement of G-protein activation, evaluation of cell surface agonist binding and computation of operational efficacies. KEY RESULTS In CHO-hM2 cells, iperoxo significantly exceeds ACh in Gi /Gs signalling competence. In the orthosteric loss-of-function mutant M2 -Y104(3.33) A, the maximum effect of iperoxo is hardly compromised in contrast to ACh. 'Superagonism' is preserved in the physiological cellular context of MRC-5 human lung fibroblasts. Structure-signalling relationships including iperoxo derivatives with either modified positively charged head group or altered tail suggest that 'superagonism' of iperoxo is mechanistically based on parallel activation of the receptor protein via two orthosteric interaction points. CONCLUSION AND IMPLICATIONS Supraphysiological agonist efficacy at muscarinic M2 ACh receptors is demonstrated for the first time. In addition, a possible underlying molecular mechanism of GPCR 'superagonism' is provided. We suggest that iperoxo-like orthosteric GPCR activation is a new avenue towards a novel class of receptor activators.
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Affiliation(s)
- R Schrage
- Pharmacology & Toxicology Section, Institute of Pharmacy, University of Bonn, Bonn, Germany
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Vartak AP. The preclinical discovery of lofexidine for the treatment of opiate addiction. Expert Opin Drug Discov 2014; 9:1371-7. [PMID: 25260380 DOI: 10.1517/17460441.2014.962995] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Lofexidine is one therapeutic option used for treating the onslaught of sympathetic outflow that typically commences upon induction of opiate withdrawal. It was approved for opiate detoxification in the UK, most of EU, and a select few countries worldwide during the 1980s and the 90s. Within the US and Canada, however, it remains an experimental drug. AREAS COVERED The following article highlights lacunae in extant knowledge about the molecular pharmacology of lofexidine. Furthermore, the article provides a brief discussion on the nature and shortcomings of clinical trials for this drug that have been conducted over the past 30 years across the world. It also provides a discussion of the market factors and regulatory considerations responsible for the rather limited use of lofexidine thus far. EXPERT OPINION Many lessons can be learned from the 40-year-long development of lofexidine. Indeed, unless there is an urgent need to address an unmet and/or immediate health threat, preclinical development is dictated by pharmacoeconomic considerations. Lofexidine would likely have been excluded for further development in this day and age given the existence and value of clonidine as well as the lack of insurance coverage for opiate addiction. It should be noted, however, that although there have been many oversights in the past, current experimentation and clinical trials are beginning to address the mistakes made through the exploration of single enantiomers and controlled-release preparations.
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Affiliation(s)
- Ashish P Vartak
- University of Minnesota, Center for Drug Design , 4-270 NHH 310 Church St. SE, Minneapolis, MN 55455 , USA +1 612 327 7630 ;
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Hong L, Sklar LA. Targeting GTPases in Parkinson's disease: comparison to the historic path of kinase drug discovery and perspectives. Front Mol Neurosci 2014; 7:52. [PMID: 24926233 PMCID: PMC4046578 DOI: 10.3389/fnmol.2014.00052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 05/18/2014] [Indexed: 11/21/2022] Open
Abstract
Neurological diseases have placed heavy social and financial burdens on modern society. As the life expectancy of humans is extended, neurological diseases, such as Parkinson’s disease, have become increasingly common among senior populations. Although the enigmas of Parkinson’s diseases await resolution, more vivid pictures on the cause, progression, and control of the illness are emerging after years of research. On the molecular level, GTPases are implicated in the etiology of Parkinson’s disease and are rational pharmaceutical targets for their control. However, targeting individual GTPases, which belong to a superfamily of proteins containing multiple members with a conserved guanine nucleotide binding domain, has proven to be challenging. In contrast, pharmaceutical pursuit of inhibition of kinases, which constitute another superfamily of proteins with more than 500 members, has been fairly successful. We reviewed the breakthroughs in the history of kinase drug discovery to provide guidance for the GTPase field. We summarize recent progress made in the regulation of GTPase activity. We also present an efficient and cost effective approach to drug screening, which uses multiplex flow cytometry and mixture-based positional scanning libraries. These methods allow simultaneous measurements of both the activity and the selectivity of the screened library. Several GTPase activator clusters were identified which showed selectivity against different GTPase subfamilies. While the clusters need to be further deconvoluted to identify individual active compounds, the method described here and the structure information gathered create a foundation for further developments to build upon.
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Affiliation(s)
- Lin Hong
- Department of Pathology, The University of New Mexico Albuquerque, NM, USA ; Center for Molecular Discovery, The University of New Mexico Albuquerque, NM, USA
| | - Larry A Sklar
- Department of Pathology, The University of New Mexico Albuquerque, NM, USA ; Center for Molecular Discovery, The University of New Mexico Albuquerque, NM, USA ; Cancer Center, The University of New Mexico Albuquerque, NM, USA
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Functional binding assays for estimation of the intrinsic efficacy of ligands at the 5-HT1A receptor: application for screening drug candidates. J Pharmacol Toxicol Methods 2014; 70:12-8. [PMID: 24636913 DOI: 10.1016/j.vascn.2014.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/17/2014] [Accepted: 03/04/2014] [Indexed: 01/04/2023]
Abstract
INTRODUCTION Determination of the intrinsic efficacy of ligands at the 5-HT1A receptor is important for selecting drug candidates, e.g. in the case of schizophrenia where partial agonism is a favorable property shared by different atypical antipsychotics. METHODS Using seven ligands with different intrinsic efficacies and rat hippocampus synaptosomes, we compared critically three "functional" binding assays based on the ternary complex model that considers that the activated conformation of the receptor is the one coupled to G-protein. RESULTS The Ki ratio method, based on the difference of affinity of the competing drug when using an antagonist vs. an agonist as radioligand, discriminated the ligands according to their intrinsic efficacies, with values from 77 for the full agonist 5-hydroxytryptamine to 0.09 for the inverse agonist WAY 100,635. The GTP-shift method, based on the decrease of affinity observed with agonists when GTP is added to the competition binding assay, was equally effective in classifying the drugs according to their intrinsic efficacy. The lower sensibility of the GTP-shift assay was investigated and explained by the different ionic conditions used in the two assays and the way competition curves were analyzed. Albeit more direct, the assay based on agonist-stimulated [(35)S]-GTPγS binding to G proteins was more expensive and of greater variability in our hands. DISCUSSION We conclude that the GTP-shift procedure described herein for 5-HT1A receptors may expedite drug discovery efforts by predicting at the same time the affinity and intrinsic efficacy of ligands through a simple, rapid and economic ligand binding assay.
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Lalanne L, Ayranci G, Kieffer BL, Lutz PE. The kappa opioid receptor: from addiction to depression, and back. Front Psychiatry 2014; 5:170. [PMID: 25538632 PMCID: PMC4258993 DOI: 10.3389/fpsyt.2014.00170] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 11/13/2014] [Indexed: 12/16/2022] Open
Abstract
Comorbidity is a major issue in psychiatry that notably associates with more severe symptoms, longer illness duration, and higher service utilization. Therefore, identifying key clusters of comorbidity and exploring the underlying pathophysiological mechanisms represent important steps toward improving mental health care. In the present review, we focus on the frequent association between addiction and depression. In particular, we summarize the large body of evidence from preclinical models indicating that the kappa opioid receptor (KOR), a member of the opioid neuromodulatory system, represents a central player in the regulation of both reward and mood processes. Current data suggest that the KOR modulates overlapping neuronal networks linking brainstem monoaminergic nuclei with forebrain limbic structures. Rewarding properties of both drugs of abuse and natural stimuli, as well as the neurobiological effects of stressful experiences, strongly interact at the level of KOR signaling. In addiction models, activity of the KOR is potentiated by stressors and critically controls drug-seeking and relapse. In depression paradigms, KOR signaling is responsive to a variety of stressors, and mediates despair-like responses. Altogether, the KOR represents a prototypical substrate of comorbidity, whereby life experiences converge upon common brain mechanisms to trigger behavioral dysregulation and increased risk for distinct but interacting psychopathologies.
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Affiliation(s)
- Laurence Lalanne
- CNRS UMR-7104, Translational Medicine and Neurogenetics, Institut de Génétique et de Biologie Moléculaire et Cellulaire, INSERM U-964, Université de Strasbourg , Illkirch , France ; Department of Psychiatry, University Hospital of Strasbourg and Medical School of Strasbourg , Strasbourg , France
| | - Gulebru Ayranci
- CNRS UMR-7104, Translational Medicine and Neurogenetics, Institut de Génétique et de Biologie Moléculaire et Cellulaire, INSERM U-964, Université de Strasbourg , Illkirch , France ; Douglas Mental Health Institute, McGill University , Montréal, QC , Canada
| | - Brigitte L Kieffer
- Douglas Mental Health Institute, McGill University , Montréal, QC , Canada
| | - Pierre-Eric Lutz
- Douglas Mental Health Institute, McGill University , Montréal, QC , Canada
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Regulation of neuronal plasticity and fear by a dynamic change in PAR1-G protein coupling in the amygdala. Mol Psychiatry 2013; 18:1136-45. [PMID: 23032873 PMCID: PMC3690134 DOI: 10.1038/mp.2012.133] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 07/24/2012] [Accepted: 08/15/2012] [Indexed: 01/01/2023]
Abstract
Fear memories are acquired through neuronal plasticity, an orchestrated sequence of events regulated at circuit and cellular levels. The conventional model of fear acquisition assumes unimodal (for example, excitatory or inhibitory) roles of modulatory receptors in controlling neuronal activity and learning. Contrary to this view, we show that protease-activated receptor-1 (PAR1) promotes contrasting neuronal responses depending on the emotional status of an animal by a dynamic shift between distinct G protein-coupling partners. In the basolateral amygdala of fear-naive mice PAR1 couples to Gαq/11 and Gαo proteins, while after fear conditioning coupling to Gαo increases. Concurrently, stimulation of PAR1 before conditioning enhanced, but afterwards it inhibited firing of basal amygdala neurons. An initial impairment of the long-term potentiation (LTP) in PAR1-deficient mice was transformed into an increase in LTP and enhancement of fear after conditioning. These effects correlated with more frequent 2-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propanoic acid (AMPA) receptor-mediated miniature post synaptic events and increased neuronal excitability. Our findings point to experience-specific shifts in PAR1-G protein coupling in the amygdala as a novel mechanism regulating neuronal excitability and fear.
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