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Makvand M, Mirtorabi SD, Campbell A, Zali A, Ahangari G. Exploring neuroadaptive cellular pathways in chronic morphine exposure: An in-vitro analysis of cabergoline and Mdivi-1 co-treatment effects on the autophagy-apoptosis axis. J Cell Biochem 2024; 125:e30558. [PMID: 38577900 DOI: 10.1002/jcb.30558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 02/08/2024] [Accepted: 03/07/2024] [Indexed: 04/06/2024]
Abstract
The complex impacts of prolonged morphine exposure continue to be a significant focus in the expanding area of addiction studies. This research investigates the effectiveness of a combined treatment using Cabergoline and Mdivi-1 to counteract the neuroadaptive changes caused by in vitro morphine treatment. The impact of Methadone, Cabergoline, and a combination of Cabergoline and Mdivi-1 on the cellular and molecular responses associated with Morphine-induced changes was studied in human Neuroblastoma (SK-N-MC) and Glioblastoma (U87-MG) cell lines that were exposed to prolong Morphine treatment. Cabergoline and Mdivi-1 combined treatment effectively influenced the molecular alterations associated with neuroadaptation in chronic morphine-exposed neural cells. This combination therapy normalized autophagy and reduced oxidative stress by enhancing total-antioxidant capacity, mitigating apoptosis, restoring BDNF expression, and balancing apoptotic elements. Our research outlines morphine's dual role in modulating mitochondrial dynamics via the dysregulation of the autophagy-apoptosis axis. This emphasizes the significant involvement of DRP1 activity in neurological adaptation processes, as well as disturbances in the dopaminergic pathway during in vitro chronic exposure to morphine in neural cells. This study proposes a novel approach by recommending the potential effectiveness of combining Cabergoline and Mdivi-1 to modulate the neuroadaptations caused by morphine. Additionally, we identified BDNF and PCNA in neural cells as potential neuroprotective markers for assessing the effectiveness of drugs against opioid toxicity, emphasizing the need for further validation. The study uncovers diverse effects observed in pretreated morphine glioblastoma cells under treatment with Cabergoline and methadone. This highlights the potential for new treatments in the DRD2 pathway and underscores the importance of investigating the interplay between autophagy and apoptosis to advance research in managing cancer-related pain. The study necessitates an in-depth investigation into the relationship between autophagy and apoptosis, with a specific emphasis on protein interactions and the dynamics of cell signaling.
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Affiliation(s)
- Mina Makvand
- Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | | | - Arezoo Campbell
- Department of Pharmaceutical Sciences, Western University of Health Sciences, Pomona, California, USA
| | - Alireza Zali
- Functional Neurosurgery Research Center, Shohada Tajrish Comprehensive Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ghasem Ahangari
- Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
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Gaborit M, Massotte D. Therapeutic potential of opioid receptor heteromers in chronic pain and associated comorbidities. Br J Pharmacol 2023; 180:994-1013. [PMID: 34883528 DOI: 10.1111/bph.15772] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 06/07/2021] [Accepted: 07/21/2021] [Indexed: 11/27/2022] Open
Abstract
Chronic pain affects 20% to 45% of the global population and is often associated with the development of anxio-depressive disorders. Treatment of this debilitating condition remains particularly challenging with opioids prescribed to alleviate moderate to severe pain. However, despite strong antinociceptive properties, numerous adverse effects limit opioid use in the clinic. Moreover, opioid misuse and abuse have become a major health concern worldwide. This prompted efforts to design original strategies that would efficiently and safely relieve pain. Targeting of opioid receptor heteromers is one of these. This review summarizes our current knowledge on the role of heteromers involving opioid receptors in the context of chronic pain and anxio-depressive comorbidities. It also examines how heteromerization in native tissue affects ligand binding, receptor signalling and trafficking properties. Finally, the therapeutic potential of ligands designed to specifically target opioid receptor heteromers is considered. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.
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Affiliation(s)
- Marion Gaborit
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Dominique Massotte
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
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3
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Role for μ-opioid receptor in antidepressant effects of δ-opioid receptor agonist KNT-127. J Pharmacol Sci 2023; 151:135-141. [PMID: 36828615 DOI: 10.1016/j.jphs.2022.12.008] [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: 07/26/2022] [Revised: 12/17/2022] [Accepted: 12/26/2022] [Indexed: 12/29/2022] Open
Abstract
Previous pharmacological data have shown the possible existence of functional interactions between μ- (MOP), κ- (KOP), and δ-opioid receptors (DOP) in pain and mood disorders. We previously reported that MOP knockout (KO) mice exhibit a lower stress response compared with wildtype (WT) mice. Moreover, DOP agonists have been shown to exert antidepressant-like effects in numerous animal models. In the present study, the tail suspension test (TST) and forced swim test (FST) were used to examine the roles of MOP and DOP in behavioral despair. MOP-KO mice and WT mice were treated with KNT-127 (10 mg/kg), a selective DOP agonist. The results indicated a significant decrease in immobility time in the KNT-127 group compared with the saline group in all genotypes in both tests. In the saline groups, immobility time significantly decreased in MOP-KO mice compared with WT mice in both tests. In female MOP-KO mice, KNT-127 significantly decreased immobility time in the TST compared with WT mice. In male MOP-KO mice, however, no genotypic differences were found in the TST after either KNT-127 or saline treatment. Thus, at least in the FST and TST, the activation of DOP and absence of MOP had additive effects in reducing measures of behavioral despair, suggesting that effects on this behavior by DOP activation occur independently of MOP.
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Delta Opioid Receptors and Enkephalinergic Signaling within Locus Coeruleus Promote Stress Resilience. Brain Sci 2022; 12:brainsci12070860. [PMID: 35884666 PMCID: PMC9320195 DOI: 10.3390/brainsci12070860] [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: 06/02/2022] [Revised: 06/28/2022] [Accepted: 06/28/2022] [Indexed: 11/16/2022] Open
Abstract
The noradrenergic nucleus locus coeruleus is a key component of the stress circuitry of the brain. During stress, the neuropeptide corticotropin-releasing factor (CRF) is secreted onto LC, increasing LC output and norepinephrine concentration in the brain, which is thought to promote anxiety-like behavior. LC is also innervated by several structures that synthesize and release the endogenous opioid peptide enkephalin onto LC upon stressor termination. While the role of CRF neurotransmission within LC in mediating anxiety-like behavior and the behavioral response to stress has been well characterized, the role of enkephalinergic signaling at LC-expressed δ-opioid receptors has been comparatively understudied. We have previously shown that acute stressor exposure increases LC activity and anxiety-like behavior for at least one week. Here, we extend these findings by showing that these effects may be mediated at least in part through stress-induced downregulation of DORs within LC. Furthermore, overexpression of DORs in LC blocks the effects of stress on both LC firing properties and anxiety-like behavior. In addition, intra-LC infusions of enkephalin blocked stress-induced freezing behavior and promoted conditioned place preference. These findings indicate that enkephalinergic neurotransmission at DORs within LC is an important component of the behavioral response to stress and may drive reward-related behavior as well.
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5
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De Sa Nogueira D, Bourdy R, Filliol D, Romieu P, Befort K. Hippocampal mu opioid receptors are modulated following cocaine self-administration in rat. Eur J Neurosci 2021; 53:3341-3349. [PMID: 33811699 DOI: 10.1111/ejn.15217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 03/18/2021] [Indexed: 11/30/2022]
Abstract
Cocaine addiction is a complex pathology induced by long-term brain changes. Understanding the neurochemical changes underlying the reinforcing effects of this drug of abuse is critical for reducing the societal burden of drug addiction. The mu opioid receptor plays a major role in drug reward. This receptor is modulated by chronic cocaine treatment in specific brain structures, but few studies investigated neurochemical adaptations induced by voluntary cocaine intake. In this study, we investigated whether intravenous cocaine-self administration (0.33 mg/kg/injection, fixed-ratio 1 [FR1], 10 days) in rats induces transcriptional and functional changes of the mu opioid receptor in reward-related brain regions. Epigenetic processes with histone modifications were examined for two activating marks, H3K4Me3, and H3K27Ac. We found an increase of mu opioid receptor gene expression along with a potentiation of its functionality in hippocampus of cocaine self-administering animals compared to saline controls. Chromatin immunoprecipitation followed by qPCR revealed no modifications of the histone mark H3K4Me3 and H3K27Ac levels at mu opioid receptor promoter. Our study highlights the hippocampus as an important target to further investigate neuroadaptive processes leading to cocaine addiction.
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Affiliation(s)
- David De Sa Nogueira
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA UMR7364), Centre de la Recherche Nationale Scientifique, Université de Strasbourg, Strasbourg, France
| | - Romain Bourdy
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA UMR7364), Centre de la Recherche Nationale Scientifique, Université de Strasbourg, Strasbourg, France
| | - Dominique Filliol
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA UMR7364), Centre de la Recherche Nationale Scientifique, Université de Strasbourg, Strasbourg, France
| | - Pascal Romieu
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA UMR7364), Centre de la Recherche Nationale Scientifique, Université de Strasbourg, Strasbourg, France
| | - Katia Befort
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA UMR7364), Centre de la Recherche Nationale Scientifique, Université de Strasbourg, Strasbourg, France
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Fujita W. The Possible Role of MOPr-DOPr Heteromers and Its Regulatory Protein RTP4 at Sensory Neurons in Relation to Pain Perception. Front Cell Neurosci 2020; 14:609362. [PMID: 33304244 PMCID: PMC7693438 DOI: 10.3389/fncel.2020.609362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/28/2020] [Indexed: 12/25/2022] Open
Abstract
Heteromers between mu opioid receptor (MOPr) and delta opioid receptor (DOPr) (i.e., MOPr-DOPr heteromer) have been found to be expressed in different brain regions, in the spinal cord, and in dorsal root ganglia. Recent studies on this heteromer reveal its important pathophysiological function in pain regulation including neuropathic pain; this suggests a role as a novel therapeutic target in chronic pain management. In addition, receptor transporter protein 4 (RTP4) has been shown to be involved in the intracellular maturation of the MOPr-DOPr heteromers. RTP4 appears to have unique distribution in vivo being highly expressed in sensory neurons and also macrophages; the latter are effector cells of the innate immune system that phagocytose foreign substances and secrete both pro-inflammatory and antimicrobial mediators; this suggests a possible contribution of RTP4 to neuronal immune-related pathological conditions such as neuropathic pain. Although RTP4 could be considered as an important therapeutic target in the management of pain via MOPr-DOPr heteromer, a few reports have supported this. This review will summarize the possible role or functions of the MOPr-DOPr heteromer and its regulatory molecule RTP4 in pain modulation at sensory neurons.
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Affiliation(s)
- Wakako Fujita
- Department of Medical Pharmacology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Faouzi A, Uprety R, Gomes I, Massaly N, Keresztes AI, Le Rouzic V, Gupta A, Zhang T, Yoon HJ, Ansonoff M, Allaoa A, Pan YX, Pintar J, Morón JA, Streicher JM, Devi LA, Majumdar S. Synthesis and Pharmacology of a Novel μ-δ Opioid Receptor Heteromer-Selective Agonist Based on the Carfentanyl Template. J Med Chem 2020; 63:13618-13637. [PMID: 33170687 DOI: 10.1021/acs.jmedchem.0c00901] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In this work, we studied a series of carfentanyl amide-based opioid derivatives targeting the mu opioid receptor (μOR) and the delta opioid receptor (δOR) heteromer as a credible novel target in pain management therapy. We identified a lead compound named MP135 that exhibits high G-protein activity at μ-δ heteromers compared to the homomeric δOR or μOR and low β-arrestin2 recruitment activity at all three. Furthermore, MP135 exhibits distinct signaling profile, as compared to the previously identified agonist targeting μ-δ heteromers, CYM51010. Pharmacological characterization of MP135 supports the utility of this compound as a molecule that could be developed as an antinociceptive agent similar to morphine in rodents. In vivo characterization reveals that MP135 maintains untoward side effects such as respiratory depression and reward behavior; together, these results suggest that optimization of MP135 is necessary for the development of therapeutics that suppress the classical side effects associated with conventional clinical opioids.
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Affiliation(s)
- Abdelfattah Faouzi
- Center for Clinical Pharmacology, St Louis College of Pharmacy and Washington University, School of Medicine, St. Louis, Missouri 63110, United States.,Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Rajendra Uprety
- Department of Neurology and Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Ivone Gomes
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - Nicolas Massaly
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Attila I Keresztes
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arkansas 85724, United States
| | - Valerie Le Rouzic
- Department of Neurology and Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Achla Gupta
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - Tiffany Zhang
- Department of Neurology and Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Hye Jean Yoon
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Michael Ansonoff
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, United States
| | - Abdullah Allaoa
- Department of Neurology and Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Ying Xian Pan
- Department of Neurology and Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - John Pintar
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, United States
| | - Jose A Morón
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States.,Department of Neuroscience and Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - John M Streicher
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arkansas 85724, United States
| | - Lakshmi A Devi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - Susruta Majumdar
- Center for Clinical Pharmacology, St Louis College of Pharmacy and Washington University, School of Medicine, St. Louis, Missouri 63110, United States.,Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
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8
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Derouiche L, Pierre F, Doridot S, Ory S, Massotte D. Heteromerization of Endogenous Mu and Delta Opioid Receptors Induces Ligand-Selective Co-Targeting to Lysosomes. Molecules 2020; 25:molecules25194493. [PMID: 33007971 PMCID: PMC7583997 DOI: 10.3390/molecules25194493] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/23/2020] [Accepted: 09/29/2020] [Indexed: 12/12/2022] Open
Abstract
Increasing evidence indicates that native mu and delta opioid receptors can associate to form heteromers in discrete brain neuronal circuits. However, little is known about their signaling and trafficking. Using double-fluorescent knock-in mice, we investigated the impact of neuronal co-expression on the internalization profile of mu and delta opioid receptors in primary hippocampal cultures. We established ligand selective mu–delta co-internalization upon activation by 1-[[4-(acetylamino)phenyl]methyl]-4-(2-phenylethyl)-4-piperidinecarboxylic acid, ethyl ester (CYM51010), [d-Ala2, NMe-Phe4, Gly-ol5]enkephalin (DAMGO), and deltorphin II, but not (+)-4-[(αR)-α-((2S,5R)-4-Allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC80), morphine, or methadone. Co-internalization was driven by the delta opioid receptor, required an active conformation of both receptors, and led to sorting to the lysosomal compartment. Altogether, our data indicate that mu–delta co-expression, likely through heteromerization, alters the intracellular fate of the mu opioid receptor, which provides a way to fine-tune mu opioid receptor signaling. It also represents an interesting emerging concept for the development of novel therapeutic drugs and strategies.
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MESH Headings
- Animals
- Cells, Cultured
- Endocytosis
- Hippocampus/cytology
- Ligands
- Lysosomes
- Mice, Inbred C57BL
- Neurons/metabolism
- Piperidines/pharmacology
- Protein Multimerization
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/metabolism
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Affiliation(s)
- Lyes Derouiche
- French National Centre for Scientific Research, Institut des Neurosciences Cellulaires et Intégratives, University of Strasbourg, 67000 Strasbourg, France; (L.D.); (F.P.); (S.O.)
| | - Florian Pierre
- French National Centre for Scientific Research, Institut des Neurosciences Cellulaires et Intégratives, University of Strasbourg, 67000 Strasbourg, France; (L.D.); (F.P.); (S.O.)
| | - Stéphane Doridot
- French National Centre for Scientific Research, Chronobiotron, 67200 Strasbourg, France;
| | - Stéphane Ory
- French National Centre for Scientific Research, Institut des Neurosciences Cellulaires et Intégratives, University of Strasbourg, 67000 Strasbourg, France; (L.D.); (F.P.); (S.O.)
| | - Dominique Massotte
- French National Centre for Scientific Research, Institut des Neurosciences Cellulaires et Intégratives, University of Strasbourg, 67000 Strasbourg, France; (L.D.); (F.P.); (S.O.)
- Correspondence:
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Morphine Induces Apoptosis, Inflammation, and Mitochondrial Oxidative Stress via Activation of TRPM2 Channel and Nitric Oxide Signaling Pathways in the Hippocampus. Mol Neurobiol 2020; 57:3376-3389. [PMID: 32524520 DOI: 10.1007/s12035-020-01975-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 06/02/2020] [Indexed: 10/24/2022]
Abstract
Morphine as an opioid is an important drug in the treatment of moderate to severe pain. Several stress factors via generation of nitric oxide (NO) and oxidative stress (OS) are responsible for the adverse effects of morphine-induced analgesia, addiction, and antinociceptive tolerance, including altered Ca2+ concentration, inflammation, OS, and release of apoptotic factors. TRPM2 is a Ca2+-permeable cation channel and it is activated by OS and NO. Hence, adverse effect of morphine addiction may occur via the OS and NO-induced TRPM2 activation. Because of the unclear etiology of morphine-induced adverse effects in the hippocampus, investigating the involvement of TRPM2 and NO synthetase (NOS) activations in the treatment of morphine-induced OS, apoptosis, and neuroinflammation is a major challenge. The hippocampal neuron of TRPM2 wild-type (TRPM2-WT) and knockout (TRPM2-KO) mice were divided into control, morphine, NOS inhibitor (L-NAME) + morphine, and TRPM2 channel blockers (ACA and 2-APB) + morphine. The morphine-induced increases of apoptosis, neuron death, OS, lipid peroxidation, caspase-3 and caspase-9, neuroinflammatory cytokines (IL-1β, TNF-α, IL-6), and Ca2+ levels in the hippocampal neuron of TRPM2-WT mouse were decreased by the L-NAME, ACA, and 2-APB treatments, although cell viability, neuron count, and reduced glutathione and glutathione peroxidase levels were increased by the treatments. However, the effects of morphine were not observed in the hippocampus of TRPM2-KO mice. Taken together, our data show that neurodegeneration adverse effects of morphine were induced by activation of TRPM2, and excessive generations of NO and OS. Thus, inhibition of TRPM2 may modulate morphine-induced neurodegeneration in the hippocampus.
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LaVigne J, Keresztes A, Chiem D, Streicher JM. The endomorphin-1/2 and dynorphin-B peptides display biased agonism at the mu opioid receptor. Pharmacol Rep 2020; 72:465-471. [PMID: 32112361 DOI: 10.1007/s43440-020-00061-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/09/2020] [Accepted: 01/30/2020] [Indexed: 12/31/2022]
Abstract
BACKGROUND Opioid agonist activation at the mu opioid receptor (MOR) can lead to a wide variety of physiological responses. Many opioid agonists share the ability to selectively and preferentially activate specific signaling pathways, a term called biased agonism. Biased opioid ligands can theoretically induce specific physiological responses and might enable the generation of drugs with improved side effect profiles. METHODS Dynorphins, enkephalins, and endomorphins are endogenous opioid agonist peptides that may possess distinct bias profiles; biased agonism of endogenous peptides could explain the selective roles of these ligands in vivo. Our purpose in the present study was to investigate biased signaling and potential underlying molecular mechanisms of bias using 35S-GTPγS and cAMP assays, specifically focusing on the role of adenylyl cyclases (ACs) and regulators of G-protein signaling proteins (RGSs) in CHO, N2a, and SH-SY5Y cell lines, all expressing the human MOR. RESULTS We found that endomorphin-1/2 preferentially activated cAMP signaling, while dynorphin-B preferentially activated 35S-GTPγS signaling in most cell lines. Experiments carried out in the presence of an isoform selective RGS-4 inhibitor, and siRNA knockdown of AC6 in N2a cells did not significantly affect the bias properties of endomorphins, suggesting that these proteins may not play a role in endomorphin bias. CONCLUSION We found that endomorphin-1/2 and dynorphin-B displayed contrasting bias profiles at the MOR, and ruled out potential AC6 and RGS4 mechanisms in this bias. This identified signaling bias could be involved in specifying endogenous peptide roles in vivo, where these peptides have low selectivity between opioid receptor family members.
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Affiliation(s)
- Justin LaVigne
- Department of Pharmacology, College of Medicine, University of Arizona, Box 245050, LSN563, 1501 N. Campbell Ave., Tucson, AZ, 85724, USA
| | - Attila Keresztes
- Department of Pharmacology, College of Medicine, University of Arizona, Box 245050, LSN563, 1501 N. Campbell Ave., Tucson, AZ, 85724, USA
| | - Daniel Chiem
- Department of Biomedical Sciences, College of Osteopathic Medicine, University of New England, Biddeford, ME, 04005, USA
| | - John M Streicher
- Department of Pharmacology, College of Medicine, University of Arizona, Box 245050, LSN563, 1501 N. Campbell Ave., Tucson, AZ, 85724, USA.
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Fuxe K, Borroto-Escuela DO. Understanding receptor heteromerization and its allosteric integration of signals. Neuropharmacology 2019; 152:1-3. [PMID: 31054939 DOI: 10.1016/j.neuropharm.2019.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| | - Dasiel O Borroto-Escuela
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Biomolecular Science, Section of Physiology, University of Urbino, Campus Scientifico Enrico Mattei, via Ca' le Suore 2, I-61029, Urbino, Italy; Observatorio Cubano de Neurociencias, Grupo Bohío-Estudio, Zayas 50, 62100, Yaguajay, Cuba.
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12
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Utilization of Biased G Protein-Coupled ReceptorSignaling towards Development of Safer andPersonalized Therapeutics. Molecules 2019; 24:molecules24112052. [PMID: 31146474 PMCID: PMC6600667 DOI: 10.3390/molecules24112052] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/19/2019] [Accepted: 05/24/2019] [Indexed: 12/12/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are involved in a wide variety of physiological processes. Therefore, approximately 40% of currently prescribed drugs have targeted this receptor family. Discovery of β-arrestin mediated signaling and also separability of G protein and β-arrestin signaling pathways have switched the research focus in the GPCR field towards development of biased ligands, which provide engagement of the receptor with a certain effector, thus enriching a specific signaling pathway. In this review, we summarize possible factors that impact signaling profiles of GPCRs such as oligomerization, drug treatment, disease conditions, genetic background, etc. along with relevant molecules that can be used to modulate signaling properties of GPCRs such as allosteric or bitopic ligands, ions, aptamers and pepducins. Moreover, we also discuss the importance of inclusion of pharmacogenomics and molecular dynamics simulations to achieve a holistic understanding of the relation between genetic background and structure and function of GPCRs and GPCR-related proteins. Consequently, specific downstream signaling pathways can be enriched while those that bring unwanted side effects can be prevented on a patient-specific basis. This will improve studies that centered on development of safer and personalized therapeutics, thus alleviating the burden on economy and public health.
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