1
|
Ochandarena NE, Niehaus JK, Tassou A, Scherrer G. Cell-type specific molecular architecture for mu opioid receptor function in pain and addiction circuits. Neuropharmacology 2023; 238:109597. [PMID: 37271281 PMCID: PMC10494323 DOI: 10.1016/j.neuropharm.2023.109597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/13/2023] [Indexed: 06/06/2023]
Abstract
Opioids are potent analgesics broadly used for pain management; however, they can produce dangerous side effects including addiction and respiratory depression. These harmful effects have led to an epidemic of opioid abuse and overdose deaths, creating an urgent need for the development of both safer pain medications and treatments for opioid use disorders. Both the analgesic and addictive properties of opioids are mediated by the mu opioid receptor (MOR), making resolution of the cell types and neural circuits responsible for each of the effects of opioids a critical research goal. Single-cell RNA sequencing (scRNA-seq) technology is enabling the identification of MOR-expressing cell types throughout the nervous system, creating new opportunities for mapping distinct opioid effects onto newly discovered cell types. Here, we describe molecularly defined MOR-expressing neuronal cell types throughout the peripheral and central nervous systems and their potential contributions to opioid analgesia and addiction.
Collapse
Affiliation(s)
- Nicole E Ochandarena
- Neuroscience Curriculum, Biological and Biomedical Sciences Program, The University of North Carolina School of Medicine, Chapel Hill, NC, 27599, USA; Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; UNC Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Jesse K Niehaus
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; UNC Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Adrien Tassou
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; UNC Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Grégory Scherrer
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; UNC Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; New York Stem Cell Foundation - Robertson Investigator, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| |
Collapse
|
2
|
Fritzwanker S, Nagel F, Kliewer A, Stammer V, Schulz S. In situ visualization of opioid and cannabinoid drug effects using phosphosite-specific GPCR antibodies. Commun Biol 2023; 6:419. [PMID: 37061609 PMCID: PMC10105690 DOI: 10.1038/s42003-023-04786-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 03/30/2023] [Indexed: 04/17/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are important signal transducers that are phosphorylated upon activation at intracellular serine and threonine residues. Although antibodies that specifically recognize the phosphorylation state of GPCRs have been available for many years, efficient immunolocalization of phosphorylated receptors in their tissues of origin has not been possible. Here, we show that phosphorylation of receptors is highly unstable during routine immunohistochemical procedures, requiring the use of appropriate phosphatase inhibitors particular during tissue perfusion, post-fixation, and cryoprotection but not during immunostaining of tissue sections. We provide proof of concept using phosphorylation state-specific μ-opioid receptor (MOP) and cannabinoid receptor 1 (CB1) antibodies. Indeed, three of four well-characterized phosphosite-specific MOP antibodies, including pS375-MOP, pT376-MOP, and pT379-MOP, showed robust neuronal immunostaining in brain and spinal cord sections of opioid-treated mice only after inclusion of phosphatase inhibitors. We then extended this approach to the CB1 receptor and demonstrated that one of three newly-generated phosphosite-specific CB1 antibodies, namely pS425-CB1, showed striking staining of fibers and varicosities in brain slices from cannabinoid-treated mice. Although subsequent experiments showed that phospho-CB1 immunostaining was less sensitive to phosphatases, we conclude that the use of phosphatase inhibitors should always be considered in the development of immunohistochemical procedures for new phosphosite-specific GPCR antibodies. In summary, we anticipate that this improved protocol will facilitate the widespread use of phosphorylation state-specific antibodies to monitor the activation of endogenous GPCRs under physiological and pharmacological conditions. Our approach may also prove useful to confirm target engagement of GPCR drug candidates in native tissues.
Collapse
Affiliation(s)
- Sebastian Fritzwanker
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Drackendorfer Straße 1, D-07747, Jena, Germany
| | - Falko Nagel
- 7TM Antibodies GmbH, Hans-Knöll-Straße 6, D-07745, Jena, Germany
| | - Andrea Kliewer
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Drackendorfer Straße 1, D-07747, Jena, Germany
| | - Viviane Stammer
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Drackendorfer Straße 1, D-07747, Jena, Germany
| | - Stefan Schulz
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, Drackendorfer Straße 1, D-07747, Jena, Germany.
- 7TM Antibodies GmbH, Hans-Knöll-Straße 6, D-07745, Jena, Germany.
| |
Collapse
|
3
|
Kaufmann J, Blum NK, Nagel F, Schuler A, Drube J, Degenhart C, Engel J, Eickhoff JE, Dasgupta P, Fritzwanker S, Guastadisegni M, Schulte C, Miess-Tanneberg E, Maric HM, Spetea M, Kliewer A, Baumann M, Klebl B, Reinscheid RK, Hoffmann C, Schulz S. A bead-based GPCR phosphorylation immunoassay for high-throughput ligand profiling and GRK inhibitor screening. Commun Biol 2022; 5:1206. [PMID: 36352263 PMCID: PMC9646841 DOI: 10.1038/s42003-022-04135-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 10/19/2022] [Indexed: 11/10/2022] Open
Abstract
Analysis of agonist-driven phosphorylation of G protein-coupled receptors (GPCRs) can provide valuable insights into the receptor activation state and ligand pharmacology. However, to date, assessment of GPCR phosphorylation using high-throughput applications has been challenging. We have developed and validated a bead-based immunoassay for the quantitative assessment of agonist-induced GPCR phosphorylation that can be performed entirely in multiwell cell culture plates. The assay involves immunoprecipitation of affinity-tagged receptors using magnetic beads followed by protein detection using phosphorylation state-specific and phosphorylation state-independent anti-GPCR antibodies. As proof of concept, five prototypical GPCRs (MOP, C5a1, D1, SST2, CB2) were treated with different agonizts and antagonists, and concentration-response curves were generated. We then extended our approach to establish selective cellular GPCR kinase (GRK) inhibitor assays, which led to the rapid identification of a selective GRK5/6 inhibitor (LDC8988) and a highly potent pan-GRK inhibitor (LDC9728). In conclusion, this versatile GPCR phosphorylation assay can be used extensively for ligand profiling and inhibitor screening. A G protein-coupled receptors (GPCRs) phosphorylation assay for cell culture plates can be used for ligand profiling and inhibitor screening, as evidenced by the identification of two GRK inhibitor compounds.
Collapse
|
4
|
Degrandmaison J, Rochon-Haché S, Parent JL, Gendron L. Knock-In Mouse Models to Investigate the Functions of Opioid Receptors in vivo. Front Cell Neurosci 2022; 16:807549. [PMID: 35173584 PMCID: PMC8841419 DOI: 10.3389/fncel.2022.807549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/04/2022] [Indexed: 12/28/2022] Open
Abstract
Due to their low expression levels, complex multi-pass transmembrane structure, and the current lack of highly specific antibodies, the assessment of endogenous G protein-coupled receptors (GPCRs) remains challenging. While most of the research regarding their functions was performed in heterologous systems overexpressing the receptor, recent advances in genetic engineering methods have allowed the generation of several unique mouse models. These animals proved to be useful to investigate numerous aspects underlying the physiological functions of GPCRs, including their endogenous expression, distribution, interactome, and trafficking processes. Given their significant pharmacological importance and central roles in the nervous system, opioid peptide receptors (OPr) are often referred to as prototypical receptors for the study of GPCR regulatory mechanisms. Although only a few GPCR knock-in mouse lines have thus far been generated, OPr are strikingly well represented with over 20 different knock-in models, more than half of which were developed within the last 5 years. In this review, we describe the arsenal of OPr (mu-, delta-, and kappa-opioid), as well as the opioid-related nociceptin/orphanin FQ (NOP) receptor knock-in mouse models that have been generated over the past years. We further highlight the invaluable contribution of such models to our understanding of the in vivo mechanisms underlying the regulation of OPr, which could be conceivably transposed to any other GPCR, as well as the limitations, future perspectives, and possibilities enabled by such tools.
Collapse
Affiliation(s)
- Jade Degrandmaison
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Département de Médecine, Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Quebec Network of Junior Pain Investigators, Sherbrooke, QC, Canada
| | - Samuel Rochon-Haché
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Département de Médecine, Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Quebec Network of Junior Pain Investigators, Sherbrooke, QC, Canada
| | - Jean-Luc Parent
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Département de Médecine, Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Jean-Luc Parent,
| | - Louis Gendron
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Quebec Pain Research Network, Sherbrooke, QC, Canada
- *Correspondence: Louis Gendron,
| |
Collapse
|