1
|
Blaine AT, van Rijn RM. Receptor expression and signaling properties in the brain, and structural ligand motifs that contribute to delta opioid receptor agonist-induced seizures. Neuropharmacology 2023; 232:109526. [PMID: 37004753 PMCID: PMC11078570 DOI: 10.1016/j.neuropharm.2023.109526] [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: 08/02/2022] [Revised: 03/10/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023]
Abstract
The δ opioid receptor (δOR) is a therapeutic target for the treatment of various neurological disorders, such as migraines, chronic pain, alcohol use, and mood disorders. Relative to μ opioid receptor agonists, δOR agonists show lower abuse liability and may be potentially safer analgesic alternatives. However, currently no δOR agonists are approved for clinical use. A small number of δOR agonists reached Phase II trials, but ultimately failed to progress due to lack of efficacy. One side effect of δOR agonism that remains poorly understood is the ability of δOR agonists to produce seizures. The lack of a clear mechanism of action is partly driven by the fact that δOR agonists range in their propensity to induce seizure behavior, with multiple δOR agonists reportedly not causing seizures. There is a significant gap in our current understanding of why certain δOR agonists are more likely to induce seizures, and what signal-transduction pathway and/or brain area is engaged to produce these seizures. In this review we provide a comprehensive overview of the current state of knowledge of δOR agonist-mediated seizures. The review was structured to highlight which agonists produce seizures, which brain regions have been implicated and which signaling mediators have been examined in this behavior. Our hope is that this review will spur future studies that are carefully designed and aimed to solve the question why certain δOR agonists are seizurogenic. Obtaining such insight may expedite the development of novel δOR clinical candidates without the risk of inducing seizures. This article is part of the Special Issue on "Opioid-induced changes in addiction and pain circuits".
Collapse
Affiliation(s)
- Arryn T Blaine
- Purdue University, Department of Medicinal Chemistry and Molecular Pharmacology, West Lafayette, IN, 47907, USA; Purdue University Interdisciplinary Life Science graduate program, West Lafayette, IN, 47907, USA
| | - Richard M van Rijn
- Purdue University, Department of Medicinal Chemistry and Molecular Pharmacology, West Lafayette, IN, 47907, USA; Purdue Institute for Integrative Neuroscience, West Lafayette, IN, 47907, USA; Purdue Institute for Drug Discovery, West Lafayette, IN, 47907, USA; Septerna Inc., South San Francisco, CA, 94080, USA.
| |
Collapse
|
2
|
Manai F, Zanoletti L, Morra G, Mansoor S, Carriero F, Bozzola E, Muscianisi S, Comincini S. Gluten Exorphins Promote Cell Proliferation through the Activation of Mitogenic and Pro-Survival Pathways. Int J Mol Sci 2023; 24:3912. [PMID: 36835317 PMCID: PMC9966116 DOI: 10.3390/ijms24043912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
Celiac disease (CD) is a chronic and systemic autoimmune disorder that affects preferentially the small intestine of individuals with a genetic predisposition. CD is promoted by the ingestion of gluten, a storage protein contained in the endosperm of the seeds of wheat, barley, rye, and related cereals. Once in the gastrointestinal (GI) tract, gluten is enzymatically digested with the consequent release of immunomodulatory and cytotoxic peptides, i.e., 33mer and p31-43. In the late 1970s a new group of biologically active peptides, called gluten exorphins (GEs), was discovered and characterized. In particular, these short peptides showed a morphine-like activity and high affinity for the δ-opioid receptor (DOR). The relevance of GEs in the pathogenesis of CD is still unknown. Recently, it has been proposed that GEs could contribute to asymptomatic CD, which is characterized by the absence of symptoms that are typical of this disorder. In the present work, GEs cellular and molecular effects were in vitro investigated in SUP-T1 and Caco-2 cells, also comparing viability effects with human normal primary lymphocytes. As a result, GEs treatments increased tumor cell proliferation by cell cycle and Cyclins activation as well as by induction of mitogenic and pro-survival pathways. Finally, a computational model of GEs interaction with DOR is provided. Altogether, the results might suggest a possible role of GEs in CD pathogenesis and on its associated cancer comorbidities.
Collapse
Affiliation(s)
- Federico Manai
- Department of Biology and Biotechnology “L.Spallanzani”, University of Pavia, 27100 Pavia, Italy
| | - Lisa Zanoletti
- Department of Biology and Biotechnology “L.Spallanzani”, University of Pavia, 27100 Pavia, Italy
- Laboratory for Mucosal Immunology, TARGID, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, 3000 Leuven, Belgium
| | - Giulia Morra
- SCITEC, Consiglio Nazionale delle Ricerche, 20131 Milano, Italy
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
| | - Samman Mansoor
- SCITEC, Consiglio Nazionale delle Ricerche, 20131 Milano, Italy
| | - Francesca Carriero
- Department of Biology and Biotechnology “L.Spallanzani”, University of Pavia, 27100 Pavia, Italy
| | - Elena Bozzola
- Pediatric Unit, I.R.C.C.S. Bambino Gesù Children Hospital, 00165 Roma, Italy
| | - Stella Muscianisi
- Cell Factory and Pediatric Hematology/Oncology, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Sergio Comincini
- Department of Biology and Biotechnology “L.Spallanzani”, University of Pavia, 27100 Pavia, Italy
| |
Collapse
|
3
|
Xu C, Cheng Y, Han M, Tao Y, Liu JG. The Agonist of Adenosine A1 Receptor Induced Desensitization of delta Opioid receptor-mediated Raf-1/MEK/ERK Signaling by Feedback Phosphorylation of Raf-1-Ser289/296/301. Neurochem Res 2022; 48:1531-1542. [PMID: 36525124 DOI: 10.1007/s11064-022-03843-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/22/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022]
Abstract
Our previous study found that activation of adenosine A1 receptor (A1R) induced phosphorylation of delta opioid receptor (DOR) and desensitization of its downstream signaling molecules, cAMP and Akt. To further investigate the effect of A1R agonist on DOR signaling and the underlying mechanism, we examined the effect of A1R activation upon binding of its agonist N6-cyclohexyl-adenosine (CHA) on DOR-mediated Raf-1/MEK/ERK activation, and found that prolonged CHA exposure resulted in downregulation of DOR-mediated Raf-1/MEK/ERK signaling pathway. CHA-treatment time dependently attenuated Raf-1-Ser338 phosphorylation induced by [D-Pen2,5] enkephalin (DPDPE), a specific agonist of DOR, and further caused downregulation of the Raf-1/MEK/ERK signaling pathway activated by DOR agonist. Moreover, CHA exposure time-dependently induced the phosphorylation of Raf-1-Ser289/296/301, the inhibitory phosphorylation sites that were regulated by negative feedback, thereby inhibiting activation of the MEK/ERK pathway, and this effect could be blocked by MEK inhibitor U0126. Finally, we proved that the heterologous desensitization of the Raf-1/MEK/ERK cascade was essential in the regulation of anti-nociceptive effect of DOR agonists by confirming that such effect was inhibited by pretreatment of CHA. Therefore, we conclude that the activation of A1R inhibits DOR-mediated MAPK signaling pathway via heterologous desensitization of the Raf-1/MEK/ERK cascade, which is a result of ERK-mediated Raf-1-Ser289/296/301 phosphorylation mediated by activation of A1R.
Collapse
|
4
|
Asghar J, Latif L, Alexander SPH, Kendall DA. Development of a novel cell-based, In-Cell Western/ERK assay system for the high-throughput screening of agonists acting on the delta-opioid receptor. Front Pharmacol 2022; 13:933356. [PMID: 36225576 PMCID: PMC9549385 DOI: 10.3389/fphar.2022.933356] [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: 04/30/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Extracellular signal-regulated kinases (ERKs) are important signaling mediators in mammalian cells and, as a result, one of the major areas of research focus. The detection and quantification of ERK phosphorylation as an index of activation is normally conducted using immunoblotting, which does not allow high-throughput drug screening. Plate-based immunocytochemical assays provide a cheaper and relatively high-throughput alternative method for quantifying ERK phosphorylation. Here, we present optimization steps aimed to increase assay sensitivity and reduce variance and cost using the LI-COR In-Cell Western (I-CW) system in a recombinant CHO-K1 cell line, over-expressing the human delta-opioid receptor (hDOPr) as a model.Methods: Cells cultured in 96-well microassay plates were stimulated with three standard/selective DOPr agonists (SNC80, ADL5859, and DADLE) and a novel selective DOPr agonist (PN6047) to elicit a phospho-ERK response as an index of activation. A number of experimental conditions were investigated during the assay development.Key results: Preliminary experiments revealed a clearly visible edge-effect which significantly increased assay variance across the plate and which was reduced by pre-incubation for 30 min at room temperature. ERK phosphorylation was detectable as early as 1 min after agonist addition, with a distinct peak at 3–5 min. Optimization of the cell seeding densities showed that 25,000 cells per well have the lowest basal phospho-ERK response and an optimal agonist ERK1/2 signal. Pre-incubation with apyrase (an ATPase) did not reduce the basal or agonist responses. All agonists produced concentration-dependent increases in phospho-ERK activation, and pertussis toxin was able to attenuate these ERK responses. Naltrindole, which is a selective DOPr antagonist, was able to antagonize the DOPr-mediated ERK activation of the ligands.Conclusion: We have developed an optimization protocol and highlighted a number of considerations when performing this high-throughput fluorescence immunocytochemical (ICC) assay measuring ERK phosphorylation in the human DOPr. The optimized protocol was found to be a more conducive option for the screening of delta agonists. This provides a basis for additional assay development to investigate opioid pharmacology. This protocol should be widely applicable for measuring ERK phosphorylation in any cell line and investigating other protein targets in GPCR drug discovery.
Collapse
Affiliation(s)
- Junaid Asghar
- Faculty of Pharmacy, Gomal University, Dera Ismail Khan, Pakistan
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
- *Correspondence: Junaid Asghar,
| | - Liaque Latif
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| | - Stephen P. H. Alexander
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| | - David A. Kendall
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| |
Collapse
|
5
|
Blaine AT, Miao Y, Yuan J, Palant S, Liu RJ, Zhang ZY, van Rijn RM. Exploration of beta-arrestin isoform signaling pathways in delta opioid receptor agonist-induced convulsions. Front Pharmacol 2022; 13:914651. [PMID: 36059958 PMCID: PMC9428791 DOI: 10.3389/fphar.2022.914651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/13/2022] [Indexed: 11/17/2022] Open
Abstract
The δ-opioid receptor (δOR) has been considered as a therapeutic target in multiple neurological and neuropsychiatric disorders particularly as δOR agonists are deemed safer alternatives relative to the more abuse-liable µ-opioid receptor drugs. Clinical development of δOR agonists, however, has been challenging in part due to the seizure-inducing effects of certain δOR agonists. Especially agonists that resemble the δOR-selective agonist SNC80 have well-established convulsive activity. Close inspection suggests that many of those seizurogenic δOR agonists efficaciously recruit β-arrestin, yet surprisingly, SNC80 displays enhanced seizure activity in β-arrestin 1 knockout mice. This finding led us to hypothesize that perhaps β-arrestin 1 is protective against, whereas β-arrestin 2 is detrimental for δOR-agonist-induced seizures. To investigate our hypothesis, we characterized three different δOR agonists (SNC80, ADL5859, ARM390) in cellular assays and in vivo in wild-type and β-arrestin 1 and β-arrestin 2 knockout mice for seizure activity. We also investigated downstream kinases associated with β-arrestin-dependent signal transduction. We discovered that δOR agonist-induced seizure activity strongly and positively correlates with β-arrestin 2 efficacy for the agonist, but that indirect inhibition of ERK activation using the MEK inhibitor SL327 did not inhibit seizure potency and duration. Inhibition of the PI3K/AKT/mTOR signaling with honokiol but not PQR530, attenuated SNC80 seizure duration in β-arrestin 1 knockout, but honokiol did not reduce SNC80-induced seizures in wild-type mice. Ultimately, our results indicate that β-arrestin 2 is correlated with δOR agonist-induced seizure intensity, but that global β-arrestin 1 knockout mice are a poor model system to investigate their mechanism of action.
Collapse
Affiliation(s)
- Arryn T. Blaine
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
- Purdue Interdisciplinary Life Sciences Graduate Program, West Lafayette, IN, United States
| | - Yiming Miao
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Jinling Yuan
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Sophia Palant
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Rebecca J. Liu
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Zhong-Yin Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
- Purdue Institute for Drug Discovery, West Lafayette, IN, United States
- Purdue University Cancer Center, West Lafayette, IN, United States
| | - Richard. M. van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
- Purdue Institute for Drug Discovery, West Lafayette, IN, United States
- Purdue University Cancer Center, West Lafayette, IN, United States
- Purdue Institute for Integrative Neuroscience, West Lafayette, IN, United States
- *Correspondence: Richard. M. van Rijn,
| |
Collapse
|
6
|
Gopalakrishnan L, Chatterjee O, Ravishankar N, Suresh S, Raju R, Mahadevan A, Prasad TSK. Opioid receptors signaling network. J Cell Commun Signal 2021; 16:475-483. [PMID: 34724150 DOI: 10.1007/s12079-021-00653-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/12/2021] [Indexed: 10/19/2022] Open
Abstract
Opioid receptors belong to the class A G-protein-coupled receptors and are activated by alkaloid opiates such as morphine, and endogenous ligands such as endorphins and enkephalins. Opioid receptors are widely distributed in the human body and are involved in numerous physiological processes through three major classical opioid receptor subtypes; the mu, delta and kappa along with a lesser characterized subtype, opioid receptor-like (ORL1). Opioids are the most potent analgesics and have been extensively used as a therapeutic drug for the treatment of pain and related disorders. Chronic administration of clinically used opioids is associated with adverse effects such as drug tolerance, addiction and constipation. Several investigations attempted to identify the molecular signaling networks associated with endogenous as well as synthetic opiates, however, there is a paucity of a cumulative depiction of these signaling events. Here, we report a systemic collection of downstream molecules pertaining to four subtypes of opioid receptors (MOR, KOR, DOR and ORL1) in the form of a signaling pathway map. We manually curated reactions induced by the activation of opioid receptors from the literature into five categories- molecular association, activation/inhibition, catalysis, transport, and gene regulation. This led to a dataset of 180 molecules, which is collectively represented in the opioid receptor signaling network following NetPath criteria. We believe that the public availability of an opioid receptor signaling pathway map can accelerate biomedical research in this area because of its high therapeutic significance. The opioid receptors signaling pathway map is uploaded to a freely available web resource, WikiPathways enabling ease of access ( https://www.wikipathways.org/index.php/Pathway:WP5093 ).
Collapse
Affiliation(s)
- Lathika Gopalakrishnan
- Institute of Bioinformatics, International Tech Park, Bangalore, 560 066, India.,Manipal Academy of Higher Education (MAHE), Manipal, 576 104, India.,Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed To Be University), Mangalore, 575 018, India
| | - Oishi Chatterjee
- Institute of Bioinformatics, International Tech Park, Bangalore, 560 066, India.,Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed To Be University), Mangalore, 575 018, India.,Amrita School of Biotechnology, Amrita Vishwa Vidyapeetham, Kollam, 690 525, India
| | - Namitha Ravishankar
- Institute of Bioinformatics, International Tech Park, Bangalore, 560 066, India
| | - Sneha Suresh
- Institute of Bioinformatics, International Tech Park, Bangalore, 560 066, India
| | - Rajesh Raju
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed To Be University), Mangalore, 575 018, India.
| | - Anita Mahadevan
- Department of Neuropathology, National Institute of Mental Health and Neurosciences, Bangalore, 560 029, India.,Human Brain Tissue Repository, National Institute of Mental Health and Neurosciences, Neurobiology Research Centre, Bangalore, 560 029, India
| | - T S Keshava Prasad
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed To Be University), Mangalore, 575 018, India.
| |
Collapse
|
7
|
Mansour A, Nagi K, Dallaire P, Lukasheva V, Le Gouill C, Bouvier M, Pineyro G. Comprehensive Signaling Profiles Reveal Unsuspected Functional Selectivity of δ-Opioid Receptor Agonists and Allow the Identification of Ligands with the Greatest Potential for Inducing Cyclase Superactivation. ACS Pharmacol Transl Sci 2021; 4:1483-1498. [PMID: 34661070 PMCID: PMC8506601 DOI: 10.1021/acsptsci.1c00019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Indexed: 11/29/2022]
Abstract
![]()
Prolonged exposure
to opioid receptor agonists triggers adaptations
in the adenylyl cyclase (AC) pathway that lead to enhanced production
of cyclic adenosine monophosphate (cAMP) upon withdrawal. This cellular
phenomenon contributes to withdrawal symptoms, hyperalgesia and analgesic
tolerance that interfere with clinical management of chronic pain
syndromes. Since δ-opioid receptors (DOPrs) are a promising
target for chronic pain management, we were interested in finding
out if cell-based signaling profiles as generated for drug discovery
purposes could inform us of the ligand potential to induce sensitization
of the cyclase path. For this purpose, signaling of DOPr agonists
was monitored at multiple effectors. The resulting signaling profiles
revealed marked functional selectivity, particularly for Met-enkephalin
(Met-ENK) whose signaling bias profile differed from those of synthetic
ligands like SNC-80 and ARM390. Signaling diversity among ligands
was systematized by clustering agonists according to similarities
in Emax and Log(τ) values for the
different responses. The classification process revealed that the
similarity in Gα/Gβγ, but not in β-arrestin
(βarr), responses was correlated with the potential of Met-ENK,
deltorphin II, (d-penicillamine2,5)-enkephalin (DPDPE), ARM390,
and SNC-80 to enhance cAMP production, all of which required Ca2+ mobilization to produce this response. Moreover, superactivation
by Met-ENK, which was the most-effective Ca2+ mobilizing
agonist, required Gαi/o activation, availability of Gβγ
subunits at the membrane, and activation of Ca2+ effectors
such as calmodulin and protein kinase C (PKC). In contrast, superactivation by (N-(l-tyrosyl)-(3S)-1,2,3,4-tetrahydroisoquinoline-3-carbonyl)-l-phenylalanyl-l-phenylalanine (TIPP), which was set
in a distinct category through clustering, required activation of
Gαi/o subunits but was independent of the Gβγ dimer
and Ca2+ mobilization, relying instead on Src and Raf-1
to induce this cellular adaptation.
Collapse
Affiliation(s)
- Ahmed Mansour
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montréal, Quebec H3T 1J4, Canada.,CHU Sainte-Justine Research Center, Montréal, Quebec H3T 1C5, Canada
| | - Karim Nagi
- College of Medicine, QU Health, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Paul Dallaire
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montréal, Quebec H3T 1J4, Canada.,CHU Sainte-Justine Research Center, Montréal, Quebec H3T 1C5, Canada
| | - Viktoriya Lukasheva
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3T 1J4, Canada
| | - Christian Le Gouill
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3T 1J4, Canada
| | - Michel Bouvier
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3T 1J4, Canada
| | - Graciela Pineyro
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montréal, Quebec H3T 1J4, Canada.,CHU Sainte-Justine Research Center, Montréal, Quebec H3T 1C5, Canada
| |
Collapse
|
8
|
Chen M, Wu S, Shen B, Fan Q, Zhang R, Zhou Y, Zhang P, Wang L, Zhang L. Activation of the δ opioid receptor relieves cerebral ischemic injury in rats via EGFR transactivation. Life Sci 2021; 273:119292. [PMID: 33667516 DOI: 10.1016/j.lfs.2021.119292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/12/2021] [Accepted: 02/21/2021] [Indexed: 12/21/2022]
Abstract
Delta opioids are thought to relieve ischemic injury and have tissue-protective properties. However, the detailed mechanisms of delta opioids have not been well identified. Receptor tyrosine kinases (RTKs), such as epidermal growth factor receptor (EGFR), have been shown to mediate downstream signals of δ opioid receptor (δOR) activation through the metalloproteinase (MMP)-dependent EGF-like growth factor (HB-EGF) excretion pathway, which is called transactivation. In this study, to investigate the role of EGFR in δOR-induced anti-ischemic effects in the brain, we applied the middle cerebral artery occlusion (MCAO) model followed by reperfusion to mimic ischemic stroke injury in rats. Pre-treatment with the δOR agonist [D-ala2, D-leu5] enkephalin (DADLE) improved the neurologic deficits and the decreased infarct volume caused by cerebral ischemia/reperfusion injury, which were blocked by the EGFR inhibitor AG1478 and the MMP inhibitor GM6001, respectively. Further results indicated that DADLE activated EGFR, Akt and ERK1/2 and upregulated EGFR expression in the hippocampus in a time-dependent manner, which were inhibited by AG1478 and GM6001. The enzyme-linked immunosorbent assay (ELISA) results showed that δOR activation led to an increase in HB-EGF release, but HB-EGF in tissue was downregulated at the mRNA and protein levels. Moreover, this protective action caused by δOR agonists may involve attenuated hippocampal cellular apoptosis. Overall, these results demonstrate that MMP-mediated transactivation of EGFR is essential for δOR agonist-induced MCAO/reperfusion injury relief. These findings provide a potential molecular mechanism for the neuroprotective property of δOR and may add new insight into mitigating or preventing injury.
Collapse
Affiliation(s)
- Meixuan Chen
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Shuo Wu
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Bing Shen
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Qingquan Fan
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Ran Zhang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Yu Zhou
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Pingping Zhang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Liecheng Wang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.
| | - Lesha Zhang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.
| |
Collapse
|
9
|
Camacho E, Marie N, Dupas Q, Martel C, Nowoczyn M, Elie N, Rochais C, Töth G, Allouche S. Impact of T161, Y318 and S363 alanine mutations on regulation of the human delta-opioid receptor (hDOPr) induced by peptidic and alkaloid agonists. Neuropharmacology 2020; 179:108286. [PMID: 32841607 DOI: 10.1016/j.neuropharm.2020.108286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 08/07/2020] [Accepted: 08/18/2020] [Indexed: 11/16/2022]
Abstract
Previously, we showed a differential regulation of the human delta-opioid receptor (hDOPr) by etorphine and [D-Pen2, D-Pen5] enkephalin (DPDPE). To understand the molecular basis of such differences, we introduced 3 alanine mutations at the residues T161. Y318 and S363. Both wild type (WT) and hDOPr mutants were expressed in HEK cells containing endogenous arrestins or CFP-tagged arrestin 3, then desensitization, internalization, recycling and phosphorylation were studied. In a context of endogenous arrestin expression, a major difference in DOPr desensitization was observed between agonists that was modified with the T161A mutation upon etorphine and with the S363A substitution upon DPDPE exposure. While both agonists induced a major receptor internalization, T161A and S363A impaired DOPr sequestration only for etorphine. However, similar level of S363 phosphorylation was measured between agonists. When CFP-tagged arrestin 3 was over-expressed, a similar profile of desensitization was measured for both agonists. In this context, all the 3 alanine mutations decreased etorphine-induced receptor desensitization. Using FRET, we showed similar interactions between WT hDOPr and arrestin 3 under DPDPE and etorphine stimulation which were delayed by both the Y318A and the S363A substitutions for etorphine. Finally, hDOPr recycling was qualitatively evaluated by microscopy and showed neither arrestin 3/hDOPr colocalization nor major impact of alanine mutations except for the S363A which impaired internalization and recycling for etorphine. The T161, Y318 and S363 residues of hDOPr could underlie the differential regulation promoted by DPDPE and etorphine.
Collapse
Affiliation(s)
- Elise Camacho
- Laboratoire de Signalisation, électrophysiologie et Imagerie des Lésions D'ischémie-reperfusion Myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Nicolas Marie
- Centre National de Recherche Scientifique, Unité Mixte de Recherche 8206, Institut National de La Santé et de La Recherche Médicale. U705, Université Paris Descartes, Laboratoire de Neuropsychopharmacologie des Addictions, 4 Avenue de L'observatoire, 75006, Paris, France
| | - Quentin Dupas
- Laboratoire de Signalisation, électrophysiologie et Imagerie des Lésions D'ischémie-reperfusion Myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Caroline Martel
- Laboratoire de Signalisation, électrophysiologie et Imagerie des Lésions D'ischémie-reperfusion Myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Marie Nowoczyn
- Laboratoire de Signalisation, électrophysiologie et Imagerie des Lésions D'ischémie-reperfusion Myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Nicolas Elie
- Plateau D'Histo-Imagerie Quantitative, CmaBio(3), SF 4206 ICORE, Normandie Univ, Caen, France
| | - Christophe Rochais
- Centre D'Etudes et de Recherche sur le Médicament de Normandie (CERMN), Normandie Univ, UNICAEN, 14000, Caen, France
| | - Geza Töth
- Biological Research Centre, Institute of Biochemistry, Hungarian Academy of Sciences, Szeged, Hungary
| | - Stéphane Allouche
- Laboratoire de Signalisation, électrophysiologie et Imagerie des Lésions D'ischémie-reperfusion Myocardique, Normandie Univ, UNICAEN, Caen, France.
| |
Collapse
|
10
|
Faouzi A, Varga BR, Majumdar S. Biased Opioid Ligands. Molecules 2020; 25:E4257. [PMID: 32948048 PMCID: PMC7570672 DOI: 10.3390/molecules25184257] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 12/12/2022] Open
Abstract
Achieving effective pain management is one of the major challenges associated with modern day medicine. Opioids, such as morphine, have been the reference treatment for moderate to severe acute pain not excluding chronic pain modalities. Opioids act through the opioid receptors, the family of G-protein coupled receptors (GPCRs) that mediate pain relief through both the central and peripheral nervous systems. Four types of opioid receptors have been described, including the μ-opioid receptor (MOR), κ-opioid receptor (KOR), δ-opioid receptor (DOR), and the nociceptin opioid peptide receptor (NOP receptor). Despite the proven success of opioids in treating pain, there are still some inherent limitations. All clinically approved MOR analgesics are associated with adverse effects, which include tolerance, dependence, addiction, constipation, and respiratory depression. On the other hand, KOR selective analgesics have found limited clinical utility because they cause sedation, anxiety, dysphoria, and hallucinations. DOR agonists have also been investigated but they have a tendency to cause convulsions. Ligands targeting NOP receptor have been reported in the preclinical literature to be useful as spinal analgesics and as entities against substance abuse disorders while mixed MOR/NOP receptor agonists are useful as analgesics. Ultimately, the goal of opioid-related drug development has always been to design and synthesize derivatives that are equally or more potent than morphine but most importantly are devoid of the dangerous residual side effects and abuse potential. One proposed strategy is to take advantage of biased agonism, in which distinct downstream pathways can be activated by different molecules working through the exact same receptor. It has been proposed that ligands not recruiting β-arrestin 2 or showing a preference for activating a specific G-protein mediated signal transduction pathway will function as safer analgesic across all opioid subtypes. This review will focus on the design and the pharmacological outcomes of biased ligands at the opioid receptors, aiming at achieving functional selectivity.
Collapse
MESH Headings
- Analgesics, Opioid/chemistry
- Analgesics, Opioid/metabolism
- Analgesics, Opioid/pharmacology
- Analgesics, Opioid/therapeutic use
- Arrestin/metabolism
- Furans/chemistry
- Furans/metabolism
- Humans
- Ligands
- Pain/drug therapy
- Pyrones/chemistry
- Pyrones/metabolism
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/metabolism
- Signal Transduction/drug effects
Collapse
Affiliation(s)
| | | | - Susruta Majumdar
- Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO 63131, USA; (A.F.); (B.R.V.)
| |
Collapse
|
11
|
Agonist-induced phosphorylation bar code and differential post-activation signaling of the delta opioid receptor revealed by phosphosite-specific antibodies. Sci Rep 2020; 10:8585. [PMID: 32444688 PMCID: PMC7244497 DOI: 10.1038/s41598-020-65589-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 05/05/2020] [Indexed: 01/08/2023] Open
Abstract
The δ-opioid receptor (DOP) is an attractive pharmacological target due to its potent analgesic, anxiolytic and anti-depressant activity in chronic pain models. However, some but not all selective DOP agonists also produce severe adverse effects such as seizures. Thus, the development of novel agonists requires a profound understanding of their effects on DOP phosphorylation, post-activation signaling and dephosphorylation. Here we show that agonist-induced DOP phosphorylation at threonine 361 (T361) and serine 363 (S363) proceeds with a temporal hierarchy, with S363 as primary site of phosphorylation. This phosphorylation is mediated by G protein-coupled receptor kinases 2 and 3 (GRK2/3) followed by DOP endocytosis and desensitization. DOP dephosphorylation occurs within minutes and is predominantly mediated by protein phosphatases (PP) 1α and 1β. A comparison of structurally diverse DOP agonists and clinically used opioids demonstrated high correlation between G protein-dependent signaling efficacies and receptor internalization. In vivo, DOP agonists induce receptor phosphorylation in a dose-dependent and agonist-selective manner that could be blocked by naltrexone in DOP-eGFP mice. Together, our studies provide novel tools and insights for ligand-activated DOP signaling in vitro and in vivo and suggest that DOP agonist efficacies may determine receptor post-activation signaling.
Collapse
|
12
|
Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2017; 68:631-700. [PMID: 27343248 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Opioids are among the most effective analgesics available and are the first choice in the treatment of acute severe pain. However, partial efficacy, a tendency to produce tolerance, and a host of ill-tolerated side effects make clinically available opioids less effective in the management of chronic pain syndromes. Given that most therapeutic opioids produce their actions via µ-opioid receptors (MOPrs), other targets are constantly being explored, among which δ-opioid receptors (DOPrs) are being increasingly considered as promising alternatives. This review addresses DOPrs from the perspective of cellular and molecular determinants of their pharmacological diversity. Thus, DOPr ligands are examined in terms of structural and functional variety, DOPrs' capacity to engage a multiplicity of canonical and noncanonical G protein-dependent responses is surveyed, and evidence supporting ligand-specific signaling and regulation is analyzed. Pharmacological DOPr subtypes are examined in light of the ability of DOPr to organize into multimeric arrays and to adopt multiple active conformations as well as differences in ligand kinetics. Current knowledge on DOPr targeting to the membrane is examined as a means of understanding how these receptors are especially active in chronic pain management. Insight into cellular and molecular mechanisms of pharmacological diversity should guide the rational design of more effective, longer-lasting, and better-tolerated opioid analgesics for chronic pain management.
Collapse
Affiliation(s)
- Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Catherine M Cahill
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Mark von Zastrow
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Peter W Schiller
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Graciela Pineyro
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| |
Collapse
|
13
|
Cahill CM, Walwyn W, Taylor AMW, Pradhan AAA, Evans CJ. Allostatic Mechanisms of Opioid Tolerance Beyond Desensitization and Downregulation. Trends Pharmacol Sci 2016; 37:963-976. [PMID: 27670390 DOI: 10.1016/j.tips.2016.08.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 08/18/2016] [Accepted: 08/19/2016] [Indexed: 12/20/2022]
Abstract
Mechanisms of opioid tolerance have focused on adaptive modifications within cells containing opioid receptors, defined here as cellular allostasis, emphasizing regulation of the opioid receptor signalosome. We review additional regulatory and opponent processes involved in behavioral tolerance, and include mechanistic differences both between agonists (agonist bias), and between μ- and δ-opioid receptors. In a process we will refer to as pass-forward allostasis, cells modified directly by opioid drugs impute allostatic changes to downstream circuitry. Because of the broad distribution of opioid systems, every brain cell may be touched by pass-forward allostasis in the opioid-dependent/tolerant state. We will implicate neurons and microglia as interactive contributors to the cumulative allostatic processes creating analgesic and hedonic tolerance to opioid drugs.
Collapse
Affiliation(s)
- Catherine M Cahill
- Department of Anesthesiology and Perioperative Care, University of California, Irvine, 837 Health Sciences Road, Irvine, CA 92697, USA
| | - Wendy Walwyn
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA
| | - Anna M W Taylor
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA
| | - Amynah A A Pradhan
- Department of Psychiatry, University of Illinois at Chicago, 1601 West Taylor Street, Chicago, IL 60612, USA
| | - Christopher J Evans
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA.
| |
Collapse
|
14
|
GRK2 Constitutively Governs Peripheral Delta Opioid Receptor Activity. Cell Rep 2016; 16:2686-2698. [PMID: 27568556 DOI: 10.1016/j.celrep.2016.07.084] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 06/24/2016] [Accepted: 07/27/2016] [Indexed: 01/07/2023] Open
Abstract
Opioids remain the standard for analgesic care; however, adverse effects of systemic treatments contraindicate long-term administration. While most clinical opioids target mu opioid receptors (MOR), those that target the delta class (DOR) also demonstrate analgesic efficacy. Furthermore, peripherally restrictive opioids represent an attractive direction for analgesia. However, opioid receptors including DOR are analgesically incompetent in the absence of inflammation. Here, we report that G protein-coupled receptor kinase 2 (GRK2) naively associates with plasma membrane DOR in peripheral sensory neurons to inhibit analgesic agonist efficacy. This interaction prevents optimal Gβ subunit association with the receptor, thereby reducing DOR activity. Importantly, bradykinin stimulates GRK2 movement away from DOR and onto Raf kinase inhibitory protein (RKIP). protein kinase C (PKC)-dependent RKIP phosphorylation induces GRK2 sequestration, restoring DOR functionality in sensory neurons. Together, these results expand the known function of GRK2, identifying a non-internalizing role to maintain peripheral DOR in an analgesically incompetent state.
Collapse
|
15
|
Effects of addictive drugs on adult neural stem/progenitor cells. Cell Mol Life Sci 2015; 73:327-48. [PMID: 26468052 DOI: 10.1007/s00018-015-2067-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/04/2015] [Accepted: 10/08/2015] [Indexed: 12/18/2022]
Abstract
Neural stem/progenitor cells (NSPCs) undergo a series of developmental processes before giving rise to newborn neurons, astrocytes and oligodendrocytes in adult neurogenesis. During the past decade, the role of NSPCs has been highlighted by studies on adult neurogenesis modulated by addictive drugs. It has been proven that these drugs regulate the proliferation, differentiation and survival of adult NSPCs in different manners, which results in the varying consequences of adult neurogenesis. The effects of addictive drugs on NSPCs are exerted via a variety of different mechanisms and pathways, which interact with one another and contribute to the complexity of NSPC regulation. Here, we review the effects of different addictive drugs on NSPCs, and the related experimental methods and paradigms. We also discuss the current understanding of major signaling molecules, especially the putative common mechanisms, underlying such effects. Finally, we review the future directions of research in this area.
Collapse
|
16
|
Zhang LS, Wang YJ, Ju YY, Zan GY, Xu C, Hong MH, Wang YH, Chi ZQ, Liu JG. Role for engagement of β-arrestin2 by the transactivated EGFR in agonist-specific regulation of δ receptor activation of ERK1/2. Br J Pharmacol 2015. [PMID: 26211551 DOI: 10.1111/bph.13254] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND AND PURPOSE β-Arrestins function as signal transducers linking GPCRs to ERK1/2 signalling either by scaffolding members of ERK1/2s cascades or by transactivating receptor tyrosine kinases through Src-mediated release of transactivating factor. Recruitment of β-arrestins to the activated GPCRs is required for ERK1/2 activation. Our previous studies showed that δ receptors activate ERK1/2 through a β-arrestin-dependent mechanism without inducing β-arrestin binding to the δ receptors. However, the precise mechanisms involved remain to be established. EXPERIMENTAL APPROACH ERK1/2 activation by δ receptor ligands was assessed using HEK293 cells in vitro and male Sprague Dawley rats in vivo. Immunoprecipitation, immunoblotting, siRNA transfection, intracerebroventricular injection and immunohistochemistry were used to elucidate the underlying mechanism. KEY RESULTS We identified a new signalling pathway in which recruitment of β-arrestin2 to the EGFR rather than δ receptor was required for its role in δ receptor-mediated ERK1/2 activation in response to H-Tyr-Tic-Phe-Phe-OH (TIPP) or morphine stimulation. Stimulation of the δ receptor with ligands leads to the phosphorylation of PKCδ, which acts upstream of EGFR transactivation and is needed for the release of the EGFR-activating factor, whereas β-arrestin2 was found to act downstream of the EGFR transactivation. Moreover, we demonstrated that coupling of the PKCδ/EGFR/β-arrestin2 transactivation pathway to δ receptor-mediated ERK1/2 activation was ligand-specific and the Ser(363) of δ receptors was crucial for ligand-specific implementation of this ERK1/2 activation pathway. CONCLUSIONS AND IMPLICATIONS The δ receptor-mediated activation of ERK1/2 is via ligand-specific transactivation of EGFR. This study adds new insights into the mechanism by which δ receptors activate ERK1/2.
Collapse
Affiliation(s)
- Le-Sha Zhang
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Yu-Jun Wang
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Yun-Yue Ju
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Gui-Ying Zan
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Chi Xu
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Min-Hua Hong
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Yu-Hua Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Zhi-Qiang Chi
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| | - Jing-Gen Liu
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica and Collaborative Innovation Center for Brain Science, Chinese Academy of Science, Shanghai, China
| |
Collapse
|
17
|
Lamberts JT, Traynor JR. Opioid receptor interacting proteins and the control of opioid signaling. Curr Pharm Des 2014; 19:7333-47. [PMID: 23448476 DOI: 10.2174/138161281942140105160625] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 02/18/2013] [Indexed: 12/31/2022]
Abstract
Opioid receptors are seven-transmembrane domain receptors that couple to intracellular signaling molecules by activating heterotrimeric G proteins. However, the receptor and G protein do not function in isolation but their activities are modulated by several accessory and scaffolding proteins. Examples include arrestins, kinases, and regulators of G protein signaling proteins. Accessory proteins contribute to the observed potency and efficacy of agonists, but also to the direction of signaling and the phenomenon of biased agonism. This review will present current knowledge of such proteins and how they may provide targets for future drug design.
Collapse
Affiliation(s)
| | - John R Traynor
- Department of Pharmacology, University of Michigan Medical School, 1301 MSRB III, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5632, USA.
| |
Collapse
|
18
|
Neumann C, Bigliardi-Qi M, Widmann C, Bigliardi PL. The δ-opioid receptor affects epidermal homeostasis via ERK-dependent inhibition of transcription factor POU2F3. J Invest Dermatol 2014; 135:471-480. [PMID: 25178105 PMCID: PMC4291683 DOI: 10.1038/jid.2014.370] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 08/14/2014] [Accepted: 08/18/2014] [Indexed: 12/02/2022]
Abstract
Neuropeptides and their receptors are present in human skin, and their importance for cutaneous homeostasis and during wound healing is increasingly appreciated. However, there is currently a lack of understanding of the molecular mechanisms by which their signaling modulates keratinocyte function. Here, we show that δ-opioid receptor (DOPr) activation inhibits proliferation of human keratinocytes, resulting in decreased epidermal thickness in an organotypic skin model. DOPr signaling markedly delayed induction of keratin intermediate filament (KRT10) during in vitro differentiation and abolished its induction in the organotypic skin model. This was accompanied by deregulation of involucrin (IVL), loricrin, and filaggrin. Analysis of the transcription factor POU2F3, which is involved in regulation of KRT10, IVL, and profilaggrin expression, revealed a DOPr-mediated extracellular signal-regulated kinase (ERK)-dependent downregulation of this factor. We propose that DOPr signaling specifically activates the ERK 1/2 mitogen-activated protein kinase pathway to regulate keratinocyte functions. Complementing our earlier studies in DOPr-deficient mice, these data suggest that DOPr activation in human keratinocytes profoundly influences epidermal morphogenesis and homeostasis.
Collapse
Affiliation(s)
- Christine Neumann
- Experimental Dermatology Laboratory, Institute of Medical Biology, A*STAR, Singapore; Doctoral School Faculty of Biology and Medicine, University of Lausanne, Dorigny, Switzerland; These authors contributed equally to this work
| | - Mei Bigliardi-Qi
- Experimental Dermatology Laboratory, Institute of Medical Biology, A*STAR, Singapore.
| | - Christian Widmann
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Paul L Bigliardi
- Experimental Dermatology Laboratory, Institute of Medical Biology, A*STAR, Singapore; Division of Rheumatology, University Medicine Cluster, National University Hospital, Singapore.
| |
Collapse
|
19
|
Charfi I, Audet N, Bagheri Tudashki H, Pineyro G. Identifying ligand-specific signalling within biased responses: focus on δ opioid receptor ligands. Br J Pharmacol 2014; 172:435-48. [PMID: 24665881 DOI: 10.1111/bph.12705] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 03/17/2014] [Accepted: 03/20/2014] [Indexed: 01/13/2023] Open
Abstract
UNLABELLED Opioids activate GPCRs to produce powerful analgesic actions but at the same time induce side effects and generate tolerance, which restrict their clinical use. Reducing this undesired response profile has remained a major goal of opioid research and the notion of 'biased agonism' is raising increasing interest as a means of separating therapeutic responses from unwanted side effects. However, to fully exploit this opportunity, it is necessary to confidently identify biased signals and evaluate which type of bias may support analgesia and which may lead to undesired effects. The development of new computational tools has made it possible to quantify ligand-dependent signalling and discriminate this component from confounders that may also yield biased responses. Here, we analyse different approaches to identify and quantify ligand-dependent bias and review different types of confounders. Focus is on δ opioid receptor ligands, which are currently viewed as promising agents for chronic pain management. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
Collapse
Affiliation(s)
- I Charfi
- Sainte-Justine Hospital Research Center, Montreal, QC, Canada; Department of Pharmacology, Faculty of Medicine, University of Montreal, Montreal, QC, Canada
| | | | | | | |
Collapse
|
20
|
Jia K, Sun D, Ling S, Tian Y, Yang X, Sui J, Tang B, Wang L. Activated δ‑opioid receptors inhibit hydrogen peroxide‑induced apoptosis in liver cancer cells through the PKC/ERK signaling pathway. Mol Med Rep 2014; 10:839-47. [PMID: 24912447 DOI: 10.3892/mmr.2014.2301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 04/14/2014] [Indexed: 11/06/2022] Open
Abstract
Apoptotic liver cancer cells have important roles in liver tumorigenesis and liver cancer progression. Recent studies have shown that δ‑opioid receptors are highly expressed in human liver and liver cancer cells. The present study aimed to investigate the role of activated δ‑opioid receptors on human liver cancer cell apoptosis and its interrelation with the mitochondria and the protein kinase C/extracellular‑signal‑regulated kinase (PKC/ERK) signaling pathway. H2O2 was used to induce apoptosis in human liver cancer cells. During apoptosis, mitochondrial transmembrane potentials were observed to decrease, cytochrome c expression was found to increase and B cell lymphoma 2 (Bcl‑2) expression decreased. These findings suggested that H2O2‑induced apoptosis was mediated through the mitochondrial pathway. Of note, activated δ‑opioid receptors were observed to inhibit H2O2‑induced apoptosis in human liver cancer cells. Following δ‑opioid receptor activation, the number of apoptotic liver cancer cells decreased, mitochondrial transmembrane potentials were restored, cytoplasmic cytochrome c and Bcl‑2‑associated X protein expression decreased and Bcl‑2 expression increased. These data suggested that δ‑opioid receptor activation inhibited mitochondria‑mediated apoptosis. In addition, activation of δ‑opioid receptors was observed to increase the expression of PKC and ERK in human liver cancer cells. Furthermore, upon inhibition of the PKC/ERK signaling pathway, the protective effect associated with the δ‑opioid receptor on liver cancer cell apoptosis was inhibited, which was not associated with the status of δ‑opioid receptor activation. These findings suggested that the PKC/ERK signaling pathway has an important role in δ‑opioid receptor‑mediated inhibition of apoptosis in human liver cancer cells.
Collapse
Affiliation(s)
- Kaiqi Jia
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| | - Deguang Sun
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| | - Sunbin Ling
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| | - Yu Tian
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| | - Xuejun Yang
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| | - Jidong Sui
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| | - Bo Tang
- Department of Hepatobiliary Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi 541001, P.R. China
| | - Liming Wang
- Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
| |
Collapse
|
21
|
Ligand- and cell-dependent determinants of internalization and cAMP modulation by delta opioid receptor (DOR) agonists. Cell Mol Life Sci 2014; 71:1529-46. [PMID: 24022593 DOI: 10.1007/s00018-013-1461-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 08/13/2013] [Accepted: 08/19/2013] [Indexed: 10/26/2022]
Abstract
Signaling bias refers to G protein-coupled receptor ligand ability to preferentially activate one type of signal over another. Bias to evoke signaling as opposed to sequestration has been proposed as a predictor of opioid ligand potential for generating tolerance. Here we measured whether delta opioid receptor agonists preferentially inhibited cyclase activity over internalization in HEK cells. Efficacy (τ) and affinity (KA) values were estimated from functional data and bias was calculated from efficiency coefficients (log τ/KA). This approach better represented the data as compared to alternative methods that estimate bias exclusively from τ values. Log (τ/KA) coefficients indicated that SNC-80 and UFP-512 promoted cyclase inhibition more efficiently than DOR internalization as compared to DPDPE (bias factor for SNC-80: 50 and for UFP-512: 132). Molecular determinants of internalization were different in HEK293 cells and neurons with βarrs contributing to internalization in both cell types, while PKC and GRK2 activities were only involved in neurons. Rank orders of ligand ability to engage different internalization mechanisms in neurons were compared to rank order of E max values for cyclase assays in HEK cells. Comparison revealed a significant reversal in rank order for cyclase E max values and βarr-dependent internalization in neurons, indicating that these responses were ligand-specific. Despite this evidence, and because kinases involved in internalization were not the same across cellular backgrounds, it is not possible to assert if the magnitude and nature of bias revealed by rank orders of maximal responses is the same as the one measured in HEK cells.
Collapse
|
22
|
Abstract
This paper is the thirty-third consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2010 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration (Section 16); and immunological responses (Section 17).
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, USA.
| |
Collapse
|
23
|
Zheng H, Chu J, Zhang Y, Loh HH, Law PY. Modulating micro-opioid receptor phosphorylation switches agonist-dependent signaling as reflected in PKCepsilon activation and dendritic spine stability. J Biol Chem 2011; 286:12724-33. [PMID: 21292762 DOI: 10.1074/jbc.m110.177089] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
A new role of G protein-coupled receptor (GPCR) phosphorylation was demonstrated in the current studies by using the μ-opioid receptor (OPRM1) as a model. Morphine induces a low level of receptor phosphorylation and uses the PKCε pathway to induce ERK phosphorylation and receptor desensitization, whereas etorphine, fentanyl, and [D-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin (DAMGO) induce extensive receptor phosphorylation and use the β-arrestin2 pathway. Blocking OPRM1 phosphorylation (by mutating Ser363, Thr370 and Ser375 to Ala) enabled etorphine, fentanyl, and DAMGO to use the PKCε pathway. This was not due to the decreased recruitment of β-arrestin2 to the receptor signaling complex, because these agonists were unable to use the PKCε pathway when β-arrestin2 was absent. In addition, overexpressing G protein-coupled receptor kinase 2 (GRK2) decreased the ability of morphine to activate PKCε, whereas overexpressing dominant-negative GRK2 enabled etorphine, fentanyl, and DAMGO to activate PKCε. Furthermore, by overexpressing wild-type OPRM1 and a phosphorylation-deficient mutant in primary cultures of hippocampal neurons, we demonstrated that receptor phosphorylation contributes to the differential effects of agonists on dendritic spine stability. Phosphorylation blockage made etorphine, fentanyl, and DAMGO function as morphine in the primary cultures. Therefore, agonist-dependent phosphorylation of GPCR regulates the activation of the PKC pathway and the subsequent responses.
Collapse
Affiliation(s)
- Hui Zheng
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455-0217, USA.
| | | | | | | | | |
Collapse
|