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Bates JN, Getsy PM, Coffee GA, Baby SM, MacFarlane PM, Hsieh YH, Knauss ZT, Bubier JA, Mueller D, Lewis SJ. L-cysteine ethyl ester prevents and reverses acquired physical dependence on morphine in male Sprague Dawley rats. Front Pharmacol 2023; 14:1303207. [PMID: 38111383 PMCID: PMC10726967 DOI: 10.3389/fphar.2023.1303207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 10/31/2023] [Indexed: 12/20/2023] Open
Abstract
The molecular mechanisms underlying the acquisition of addiction/dependence on morphine may result from the ability of the opioid to diminish the transport of L-cysteine into neurons via inhibition of excitatory amino acid transporter 3 (EAA3). The objective of this study was to determine whether the co-administration of the cell-penetrant L-thiol ester, L-cysteine ethyl ester (L-CYSee), would reduce physical dependence on morphine in male Sprague Dawley rats. Injection of the opioid-receptor antagonist, naloxone HCl (NLX; 1.5 mg/kg, IP), elicited pronounced withdrawal phenomena in rats which received a subcutaneous depot of morphine (150 mg/kg) for 36 h and were receiving a continuous infusion of saline (20 μL/h, IV) via osmotic minipumps for the same 36 h period. The withdrawal phenomena included wet-dog shakes, jumping, rearing, fore-paw licking, 360° circling, writhing, apneas, cardiovascular (pressor and tachycardia) responses, hypothermia, and body weight loss. NLX elicited substantially reduced withdrawal syndrome in rats that received an infusion of L-CYSee (20.8 μmol/kg/h, IV) for 36 h. NLX precipitated a marked withdrawal syndrome in rats that had received subcutaneous depots of morphine (150 mg/kg) for 48 h) and a co-infusion of vehicle. However, the NLX-precipitated withdrawal signs were markedly reduced in morphine (150 mg/kg for 48 h)-treated rats that began receiving an infusion of L-CYSee (20.8 μmol/kg/h, IV) at 36 h. In similar studies to those described previously, neither L-cysteine nor L-serine ethyl ester (both at 20.8 μmol/kg/h, IV) mimicked the effects of L-CYSee. This study demonstrates that 1) L-CYSee attenuates the development of physical dependence on morphine in male rats and 2) prior administration of L-CYSee reverses morphine dependence, most likely by intracellular actions within the brain. The lack of the effect of L-serine ethyl ester (oxygen atom instead of sulfur atom) strongly implicates thiol biochemistry in the efficacy of L-CYSee. Accordingly, L-CYSee and analogs may be a novel class of therapeutics that ameliorate the development of physical dependence on opioids in humans.
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Affiliation(s)
- James N. Bates
- Department of Anesthesiology, University of Iowa Hospitals and Clinics, Iowa City, IA, United States
| | - Paulina M. Getsy
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Gregory A. Coffee
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Santhosh M. Baby
- Section of Biology, Galleon Pharmaceuticals, Inc., Horsham, PA, United States
| | - Peter M. MacFarlane
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Yee-Hsee Hsieh
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Zackery T. Knauss
- Department of Biological Sciences, Kent State University, Kent, OH, United States
| | | | - Devin Mueller
- Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Stephen J. Lewis
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, United States
- Functional Electrical Stimulation Center, Case Western Reserve University, Cleveland, OH, United States
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Johnson K, Doucette A, Edwards A, Verdi A, McFarland R, Hulke S, Fowler A, Watts VJ, Klein AH. Reduced activity of adenylyl cyclase 1 attenuates morphine induced hyperalgesia and inflammatory pain in mice. Front Pharmacol 2022; 13:937741. [PMID: 36120355 PMCID: PMC9479488 DOI: 10.3389/fphar.2022.937741] [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: 05/06/2022] [Accepted: 08/02/2022] [Indexed: 11/29/2022] Open
Abstract
Opioid tolerance, opioid-induced hyperalgesia during repeated opioid administration, and chronic pain are associated with upregulation of adenylyl cyclase activity. The objective of this study was to test the hypothesis that a reduction in adenylyl cyclase 1 (AC1) activity or expression would attenuate morphine tolerance and hypersensitivity, and inflammatory pain using murine models. To investigate opioid tolerance and opioid-induced hyperalgesia, mice were subjected to twice daily treatments of saline or morphine using either a static (15 mg/kg, 5 days) or an escalating tolerance paradigm (10–40 mg/kg, 4 days). Systemic treatment with an AC1 inhibitor, ST03437 (2.5–10 mg/kg, IP), reduced morphine-induced hyperalgesia in mice. Lumbar intrathecal administration of a viral vector incorporating a short-hairpin RNA targeting Adcy1 reduced morphine-induced hypersensitivity compared to control mice. In contrast, acute morphine antinociception, along with thermal paw withdrawal latencies, motor performance, exploration in an open field test, and burrowing behaviors were not affected by intrathecal Adcy1 knockdown. Knockdown of Adcy1 by intrathecal injection also decreased inflammatory mechanical hyperalgesia and increased burrowing and nesting activity after intraplantar administration of Complete Freund’s Adjuvant (CFA) one-week post-injection.
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Affiliation(s)
- Kayla Johnson
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Alexis Doucette
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Alexis Edwards
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Aleeya Verdi
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Ryan McFarland
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Shelby Hulke
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Amanda Fowler
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
| | - Val J. Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Amanda H. Klein
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, United States
- *Correspondence: Amanda H. Klein,
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Michel J, Sauter L, Neunhoeffer F, Hofbeck M, Kumpf M, Paulsen F, Schmidt A, Fuchs J. Sedation practices during high dose rate brachytherapy for children with urogenital and perianal rhabdomyosarcoma. J Pediatr Surg 2022; 57:1432-1438. [PMID: 33189299 DOI: 10.1016/j.jpedsurg.2020.10.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/19/2020] [Accepted: 10/22/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND A novel concept for an organ-preserving treatment of pediatric urogenital and perianal rhabdomyosarcoma includes high dose rate brachytherapy following surgical tumor resection. For the duration of the brachytherapy of 6 days plus 2-day recovery break the patients are not allowed to move and are kept under deep sedation, which can lead to difficult weaning from mechanical ventilation, withdrawal, delirium, and prolonged hospital stay. The aim of this study was to evaluate a protocol which includes a switch from fentanyl to ketamine 3 days prior to extubation to help ensure a rapid extubation and transfer from PICU. METHODS Patients who underwent surgical tumor resection of rhabdomyosarcoma and subsequent brachytherapy were treated according to a standardized protocol. We evaluated doses of fentanyl, midazolam and clonidine, time of extubation, length of PICU stay and occurrence of withdrawal symptoms and delirium. We compared fentanyl dose at time of extubation, duration of weaning from mechanical ventilation and time to discharge from PICU with patients after isolated severe traumatic brain injury. RESULTS Twentytwo patients (age 39.9 ± 29.8 months) were treated in our PICU to undergo brachytherapy. Extubation was performed 21.6 ± 13.5 h after the last brachytherapy session with an average fentanyl dose of 1.5 ± 0.5 µg/kg/h and patients were discharged from PICU 58.4 ± 30.3 h after extubation, which all is significantly lower compared to the control group (extubation after 88.0 ± 42.2 h, p < 0.001; fentanyl dose at the time of extubation 2.5 ± 0.6 µg/kg/h, p < 0.001; PICU discharge after 130.1 ± 148.4 h, p < 0.009). Withdrawal symptoms were observed in 9 patients and delirium in 13 patients. CONCLUSION A standardized analgesia and sedation protocol including an opioid break, scoring systems to detect withdrawal symptoms and delirium, and tapering plans contributes to successful early extubation and discharge from PICU after long-term deep sedation.
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Affiliation(s)
- Jörg Michel
- Department of Pediatric Cardiology, Pulmonology and Pediatric Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany.
| | - Luisa Sauter
- Department of Pediatric Cardiology, Pulmonology and Pediatric Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
| | - Felix Neunhoeffer
- Department of Pediatric Cardiology, Pulmonology and Pediatric Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
| | - Michael Hofbeck
- Department of Pediatric Cardiology, Pulmonology and Pediatric Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
| | - Matthias Kumpf
- Department of Pediatric Cardiology, Pulmonology and Pediatric Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
| | - Frank Paulsen
- Department of Radiation Oncology, University Hospital, Hoppe-Seyler-Str. 3, 72076 Tübingen, Germany
| | - Andreas Schmidt
- Department of Pediatric Surgery and Pediatric Urology, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
| | - Jörg Fuchs
- Department of Pediatric Surgery and Pediatric Urology, University Children's Hospital Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
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Scott JA, Soto-Velasquez M, Hayes MP, LaVigne JE, Miller HR, Kaur J, Ejendal KFK, Watts VJ, Flaherty DP. Optimization of a Pyrimidinone Series for Selective Inhibition of Ca 2+/Calmodulin-Stimulated Adenylyl Cyclase 1 Activity for the Treatment of Chronic Pain. J Med Chem 2022; 65:4667-4686. [PMID: 35271288 PMCID: PMC9390083 DOI: 10.1021/acs.jmedchem.1c01759] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Adenylyl cyclase type 1 (AC1) is involved in signaling for chronic pain sensitization in the central nervous system and is an emerging target for the treatment of chronic pain. AC1 and a closely related isoform AC8 are also implicated to have roles in learning and memory signaling processes. Our team has carried out cellular screening for inhibitors of AC1 yielding a pyrazolyl-pyrimidinone scaffold with low micromolar potency against AC1 and selectivity versus AC8. Structure-activity relationship (SAR) studies led to analogues with cellular IC50 values as low as 0.25 μM, selectivity versus AC8 and other AC isoforms as well as other common neurological targets. A representative analogue displayed modest antiallodynic effects in a mouse model of inflammatory pain. This series represents the most potent and selective inhibitors of Ca2+/calmodulin-stimulated AC1 activity to date with improved drug-like physicochemical properties making them potential lead compounds for the treatment of inflammatory pain.
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Affiliation(s)
- Jason A Scott
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Monica Soto-Velasquez
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Michael P Hayes
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Justin E LaVigne
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Heath R Miller
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jatinder Kaur
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Karin F K Ejendal
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute for Drug Discovery, West Lafayette, Indiana 47907, United States
- Purdue Institute for Integrative Neuroscience, 207 South Martin Jischke Dr. West Lafayette, Indiana 47907, United States
| | - Daniel P Flaherty
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute for Drug Discovery, West Lafayette, Indiana 47907, United States
- Purdue Institute for Integrative Neuroscience, 207 South Martin Jischke Dr. West Lafayette, Indiana 47907, United States
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5
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Ostrom KF, LaVigne JE, Brust TF, Seifert R, Dessauer CW, Watts VJ, Ostrom RS. Physiological Roles of Mammalian Transmembrane Adenylyl Cyclase Isoforms. Physiol Rev 2021; 102:815-857. [PMID: 34698552 DOI: 10.1152/physrev.00013.2021] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors. The transmembrane ACs display varying expression patterns across tissues, giving potential for them having a wide array of physiologic roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gαs so it was long assumed that all ACs are activated by Gαs-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form prearranged signaling complexes with specific GPCRs that contribute to cAMP signaling compartments. This compartmentation allows for a diversity of cellular and physiological responses by enabling unique signaling events to be triggered by different pools of cAMP. Isoform specific pharmacological activators or inhibitors are lacking for most ACs, making knockdown and overexpression the primary tools for examining the physiological roles of a given isoform. Much progress has been made in understanding the physiological effects mediated through individual transmembrane ACs. GPCR-AC-cAMP signaling pathways play significant roles in regulating functions of every cell and tissue, so understanding each AC isoform's role holds potential for uncovering new approaches for treating a vast array of pathophysiological conditions.
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Affiliation(s)
- Katrina F Ostrom
- W. M. Keck Science Department, Claremont McKenna College, Claremont, CA, United States
| | - Justin E LaVigne
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Tarsis F Brust
- Department of Pharmaceutical Sciences, Palm Beach Atlantic University, West Palm Beach, FL, United States
| | - Roland Seifert
- Institute of Pharmacology, Hannover Medical School, Hannover, Germany
| | - Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas, United States
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN, United States.,Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, United States
| | - Rennolds S Ostrom
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, United States
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6
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O'Brien JB, Roman DL. Novel treatments for chronic pain: moving beyond opioids. Transl Res 2021; 234:1-19. [PMID: 33727192 DOI: 10.1016/j.trsl.2021.03.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 02/06/2023]
Abstract
It is essential that safe and effective treatment options be available to patients suffering from chronic pain. The emergence of an opioid epidemic has shaped public opinions and created stigmas surrounding the use of opioids for the management of pain. This reality, coupled with high risk of adverse effects from chronic opioid use, has led chronic pain patients and their healthcare providers to utilize nonopioid treatment approaches. In this review, we will explore a number of cellular reorganizations that are associated with the development and progression of chronic pain. We will also discuss the safety and efficacy of opioid and nonopioid treatment options for chronic pain. Finally, we will review the evidence for adenylyl cyclase type 1 (AC1) as a novel target for the treatment of chronic pain.
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Affiliation(s)
- Joseph B O'Brien
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa
| | - David L Roman
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa; Iowa Neuroscience Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa.
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7
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Cheng F, McMillan C, Morrison A, Berkwitt A, Grossman M. Neonatal Abstinence Syndrome: Management Advances and Therapeutic Approaches. CURRENT ADDICTION REPORTS 2021. [DOI: 10.1007/s40429-021-00387-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Ji MJ, Yang J, Gao ZQ, Zhang L, Liu C. The Role of the Kappa Opioid System in Comorbid Pain and Psychiatric Disorders: Function and Implications. Front Neurosci 2021; 15:642493. [PMID: 33716658 PMCID: PMC7943636 DOI: 10.3389/fnins.2021.642493] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 01/27/2021] [Indexed: 01/25/2023] Open
Abstract
Both pain and psychiatric disorders, such as anxiety and depression, significantly impact quality of life for the sufferer. The two also share a strong pathological link: chronic pain-induced negative affect drives vulnerability to psychiatric disorders, while patients with comorbid psychiatric disorders tend to experience exacerbated pain. However, the mechanisms responsible for the comorbidity of pain and psychiatric disorders remain unclear. It is well established that the kappa opioid system contributes to depressive and dysphoric states. Emerging studies of chronic pain have revealed the role and mechanisms of the kappa opioid system in pain processing and, in particular, in the associated pathological alteration of affection. Here, we discuss the key findings and summarize compounds acting on the kappa opioid system that are potential candidates for therapeutic strategies against comorbid pain and psychiatric disorders.
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Affiliation(s)
- Miao-Jin Ji
- Jiangsu Province Key Laboratory of Anesthesiology and Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, School of Anesthesiology, Xuzhou Medical University, Xuzhou, China
| | - Jiao Yang
- Jiangsu Province Key Laboratory of Anesthesiology and Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, School of Anesthesiology, Xuzhou Medical University, Xuzhou, China
| | - Zhi-Qiang Gao
- Jiangsu Province Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Liang Zhang
- Department of Neurology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chao Liu
- Jiangsu Province Key Laboratory of Anesthesiology and Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, School of Anesthesiology, Xuzhou Medical University, Xuzhou, China
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Kahremany S, Hofmann L, Gruzman A, Cohen G. Advances in Understanding the Initial Steps of Pruritoceptive Itch: How the Itch Hits the Switch. Int J Mol Sci 2020; 21:ijms21144883. [PMID: 32664385 PMCID: PMC7402353 DOI: 10.3390/ijms21144883] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 02/07/2023] Open
Abstract
Pruritoceptive (dermal) itch was long considered an accompanying symptom of diseases, a side effect of drug applications, or a temporary sensation induced by invading pruritogens, as produced by the stinging nettle. Due to extensive research in recent years, it was possible to provide detailed insights into the mechanism of itch mediation and modulation. Hence, it became apparent that pruritus is a complex symptom or disease in itself, which requires particular attention to improve patients’ health. Here, we summarize recent findings in pruritoceptive itch, including how this sensation is triggered and modulated by diverse endogenous and exogenous pruritogens and their receptors. A differentiation between mediating pruritogen and modulating pruritogen seems to be of great advantage to understand and decipher the molecular mechanism of itch perception. Only a comprehensive view on itch sensation will provide a solid basis for targeting this long-neglected adverse sensation accompanying numerous diseases and many drug side effects. Finally, we identify critical aspects of itch perception that require future investigation.
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Affiliation(s)
- Shirin Kahremany
- Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (L.H.); (A.G.)
- The Skin Research Institute, The Dead Sea and Arava Science Center, Masada 86910, Israel;
- Correspondence:
| | - Lukas Hofmann
- Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (L.H.); (A.G.)
| | - Arie Gruzman
- Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (L.H.); (A.G.)
| | - Guy Cohen
- The Skin Research Institute, The Dead Sea and Arava Science Center, Masada 86910, Israel;
- Ben-Gurion University of the Negev, Eilat Campus, Eilat 8855630, Israel
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10
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Walters RA, Izquierdo M, Rodriguez JC, Stevens JS, Lavandosky G. Iatrogenic Opiate Withdrawal in Pediatric Patients: Implementation of a Standardized Methadone Weaning Protocol and Withdrawal Assessment Tool. J Pharm Pract 2019; 34:417-422. [PMID: 31530073 DOI: 10.1177/0897190019875613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Methadone is frequently used to prevent withdrawal symptoms secondary to intended therapeutic opiate exposure. Absence of a standardized dose weaning strategy potentially results in increased exposure to narcotics and/or withdrawal symptoms. We sought to quantify the effect of implementing a standardized methadone weaning protocol and withdrawal assessment tool on methadone exposure and opiate withdrawal in pediatric patients receiving 5 or more days of continuous morphine or fentanyl infusions. The preintervention phase included patients weaned off of opiate infusions before implementation of a standardized weaning protocol and withdrawal symptom scoring tool. Patients in the postintervention phase were started on a standardized methadone wean based on total duration and dose of continuous opiate infusion exposure in the 24 hours preceding methadone initiation. Patients received either a 5- or 10-day wean, with the total daily methadone dose reduced by 20% daily or every other day, respectively. Patients in the postintervention phase were monitored for withdrawal using the withdrawal assessment tool (WAT-1). Postintervention patients were compared to preintervention patients treated with methadone. Total methadone duration decreased significantly from a median of 17 (13-22 interquartile range [IQR]) to 5 (5-10 IQR) days (P = .00001) after implementation of the methadone weaning protocol. Number of morphine boluses administered increased from a median of 3 (0-6 IQR) to 4 (0-5 IQR) doses per patient (P = .45). Demographic data were similar between both groups. Patients in the postintervention phase had significant reductions in methadone exposure after implementation of a standardized methadone weaning protocol and assessment tool.
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Affiliation(s)
- Ryan A Walters
- Department of Pharmacy, 23454Joe DiMaggio Children's Hospital, Hollywood, FL, USA
| | - Michael Izquierdo
- Department of Pharmacy, 23454Joe DiMaggio Children's Hospital, Hollywood, FL, USA
| | | | - Joanie Spiro Stevens
- Department of Pharmacy, 23454Joe DiMaggio Children's Hospital, Hollywood, FL, USA
| | - Gerald Lavandosky
- Division of Pediatric Critical Care Medicine, 23454Joe DiMaggio Children's Hospital, Hollywood, FL, USA
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11
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Price T, Brust TF. Adenylyl cyclase 7 and neuropsychiatric disorders: A new target for depression? Pharmacol Res 2019; 143:106-112. [PMID: 30904753 DOI: 10.1016/j.phrs.2019.03.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 12/28/2022]
Abstract
Adenylyl cyclases (ACs) are enzymes that catalyze the production of cyclic adenosine monophosphate (cAMP) from adenosine triphosphate (ATP). Humans express nine isoforms of membranous ACs and a soluble AC. Studies with genetic knockout or overexpression rodent models have indicated that AC isoforms may be targeted to achieve specific therapeutic outcomes. AC1, for instance, has been suggested and pursued as a target for relieving pain. Notably, previous studies examining genetically modified mice as well as human genetic polymorphisms have suggested a link between AC7 activity and depressive disorders. In the present review we present an overview on AC function and discuss the most recent developments to target AC isoforms for drug therapies. We next focus on discussing the available literature on the molecular and animal pharmacology of AC7 highlighting the available studies on the role of AC7 in depressive disorders. In addition, we discuss other possible physiological functions of AC7 relating to ethanol effects and the immune system and conclude with considerations about pharmacological modulation of AC7.
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Affiliation(s)
- Tatum Price
- Department of Pharmaceutical Sciences, Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, FL 33416, United States
| | - Tarsis F Brust
- Department of Pharmaceutical Sciences, Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, FL 33416, United States..
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12
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Abstract
Neonatal abstinence syndrome refers to the signs and symptoms attributed to the cessation of prenatal exposure (via placental transfer) to various substances. This Primer focuses on neonatal abstinence syndrome caused by opioid use during pregnancy - neonatal opioid withdrawal syndrome (NOWS). As the global prevalence of opioid use has alarmingly increased, so has the incidence of NOWS. NOWS can manifest with varying severity or not at all, for unknown reasons, but is likely to be associated with multiple factors, both maternal (for example, smoking and additional substance exposures) and neonatal (gestational age, sex and genetics). Care for the infant with NOWS begins with addressing the issues experienced by pregnant women with opioid use disorder. Co-occurring mental illness, economic hardship, intimate partner violence, infectious diseases and limited access to care are common in these women and can result in poor maternal and neonatal outcomes. Although there is no consensus regarding optimal NOWS management, non-pharmacological interventions (such as breastfeeding and rooming-in of the mother and the baby) have become a priority, as they can ameliorate symptoms without the need for further opioid exposure. Untreated NOWS can be associated with morbidity in early infancy, and the long-term consequences of fetal opioid exposure are only beginning to be understood.
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Affiliation(s)
- Mara G Coyle
- Department of Pediatrics, The Warren Alpert Medical School of Brown University, Providence, RI, USA.
| | - Susan B Brogly
- Department of Surgery, Queen's University, Kingston, Ontario, Canada
| | - Mahmoud S Ahmed
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Stephen W Patrick
- Vanderbilt Center for Child Health Policy, Department of Pediatrics and Health Policy, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Hendrée E Jones
- Department of Obstetrics and Gynecology, University of North Carolina, Carrboro, NC, USA
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Rashki A, Mumtaz F, Jazayeri F, Shadboorestan A, Esmaeili J, Ejtemaei Mehr S, Ghahremani MH, Dehpour AR. Cyclosporin A attenuating morphine tolerance through inhibiting NO/ERK signaling pathway in human glioblastoma cell line: the involvement of calcineurin. EXCLI JOURNAL 2018; 17:1137-1151. [PMID: 30713473 PMCID: PMC6341459 DOI: 10.17179/excli2018-1693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 10/06/2018] [Indexed: 12/16/2022]
Abstract
Cyclosporin A (CsA) is known to have an immunosuppressive action. However, it is also attracting attention due to its effects on the nervous system, such as inhibiting the development and expression of morphine-induced tolerance and dependence through unknown mechanisms. It has been shown that CsA modulates the nitric oxide (NO) synthesis and extracellular signal-regulated kinases (ERK) activation, which are potentially involved in signaling pathways in morphine-induced tolerance in cellular models. Therefore, the current study was designed to evaluate the modulatory role of CsA on the MOR tolerance, by targeting the downstream signaling pathway of NO and ERK using an in vitro model. For this purpose, T98G cells were pretreated with CsA, calcineurin autoinhibitory peptide (CAIP), and NG-nitro-l-arginine methyl ester (L-NAME) 30 min before 18 h exposure to MOR. Then, we analyzed the intracellular cyclic adenosine monophosphate (cAMP) levels and also the expression of phosphorylated ERK and nitric oxide synthase (nNOS) proteins. Our results showed that CsA (1 nM, 10 nM, and 100 nM) and CAIP (50 µM) have significantly reduced cAMP and nitrite levels as compared to MOR-treated (2.5 µM) T98G cells. This clearly revealed the attenuation of MOR tolerance by CsA. The expression of nNOS and p-ERK proteins were down-regulated when the T98G cells were pretreated with CsA (1 nM, 10 nM, and 100 nM), CAIP (50 µM), and L-NAME (0.1 mM) as compared to MOR. In conclusion, the CsA pretreatment had a modulatory role in MOR-induced tolerance, which was possibly mediated through NO/ERK signaling pathway.
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Affiliation(s)
- Asma Rashki
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran.,Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Faiza Mumtaz
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran.,Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Farahnaz Jazayeri
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Amir Shadboorestan
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Jamileh Esmaeili
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Shahram Ejtemaei Mehr
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Hossein Ghahremani
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Reza Dehpour
- Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran.,Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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14
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Zhang L, Kibaly C, Wang YJ, Xu C, Song KY, McGarrah PW, Loh HH, Liu JG, Law PY. Src-dependent phosphorylation of μ-opioid receptor at Tyr 336 modulates opiate withdrawal. EMBO Mol Med 2018; 9:1521-1536. [PMID: 28818835 PMCID: PMC5666313 DOI: 10.15252/emmm.201607324] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Opiate withdrawal/negative reinforcement has been implicated as one of the mechanisms for the progression from impulsive to compulsive drug use. Increase in the intracellular cAMP level and protein kinase A (PKA) activities within the neurocircuitry of addiction has been a leading hypothesis for opiate addiction. This increase requires the phosphorylation of μ‐opioid receptor (MOR) at Tyr336 by Src after prolonged opiate treatment in vitro. Here, we report that the Src‐mediated MOR phosphorylation at Tyr336 is a prerequisite for opiate withdrawal in mice. We observed the recruitment of Src in the vicinity of MOR and an increase in phosphorylated Tyr336 (pY336) levels during naloxone‐precipitated withdrawal. The intracerebroventricular or stereotaxic injection of a Src inhibitor (AZD0530), or Src shRNA viruses attenuated pY336 levels, and several somatic withdrawal signs. This was also observed in Fyn−/− mice. The stereotaxic injection of wild‐type MOR, but not mutant (Y336F) MOR, lentiviruses into the locus coeruleus of MOR−/− mice restored somatic withdrawal jumping. Regulating pY336 levels during withdrawal might be a future target for drug development to prevent opiate addictive behaviors.
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Affiliation(s)
- Lei Zhang
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Cherkaouia Kibaly
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - 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
| | - Chi Xu
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Kyu Young Song
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Patrick W McGarrah
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Horace H Loh
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - 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
| | - Ping-Yee Law
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, USA
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15
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Prolonged Morphine Treatment Alters Expression and Plasma Membrane Distribution of β-Adrenergic Receptors and Some Other Components of Their Signaling System in Rat Cerebral Cortex. J Mol Neurosci 2017; 63:364-376. [PMID: 29081032 DOI: 10.1007/s12031-017-0987-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/05/2017] [Indexed: 01/15/2023]
Abstract
β-Adrenergic signaling plays an important role in regulating diverse brain functions and alterations in this signaling have been observed in different neuropathological conditions. In this study, we investigated the effect of a 10-day treatment with high doses of morphine (10 mg/kg per day) on major components and functional state of the β-adrenergic receptor (β-AR) signaling system in the rat cerebral cortex. β-ARs were characterized by radioligand binding assays and amounts of various G protein subunits, adenylyl cyclase (AC) isoforms, G protein-coupled receptor kinases (GRKs), and β-arrestin were examined by Western blot analysis. AC activity was determined as a measure of functionality of the signaling system. We also assessed the partitioning of selected signaling proteins between the lipid raft and non-raft fractions prepared from cerebrocortical plasma membranes. Morphine treatment resulted in a significant upregulation of β-ARs, GRK3, and some AC isoforms (AC-I, -II, and -III). There was no change in quantity of G proteins and some other signaling molecules (AC-IV, AC-V/VI, GRK2, GRK5, GRK6, and β-arrestin) compared with controls. Interestingly, morphine exposure caused a partial redistribution of β-ARs, Gsα, Goα, and GRK2 between lipid rafts and bulk plasma membranes. Spatial localization of other signaling molecules within the plasma membrane was not changed. Basal as well as fluoride- and forskolin-stimulated AC activities were not significantly different in membrane preparations from control and morphine-treated animals. However, AC activity stimulated by the beta-AR agonist isoprenaline was markedly increased. This is the first study to demonstrate lipid raft association of key components of the cortical β-AR system and its sensitivity to morphine.
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Neunhoeffer F, Hanser A, Esslinger M, Icheva V, Kumpf M, Gerbig I, Hofbeck M, Michel J. Ketamine Infusion as a Counter Measure for Opioid Tolerance in Mechanically Ventilated Children: A Pilot Study. Paediatr Drugs 2017; 19:259-265. [PMID: 28299720 DOI: 10.1007/s40272-017-0218-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Drug rotation to prevent opioid tolerance is well recognized in chronic pain management. However, ketamine infusion as a counter measure for opioid tolerance is rarely described in mechanically ventilated children developing tolerance from prolonged opioid infusion. PATIENTS AND METHODS We performed a retrospective study in a 14-bed medical-surgical-cardiac pediatric intensive care unit. Thirty-two mechanically ventilated children who had developed tolerance from prolonged intravenous infusion of opioids received a continuous intravenous infusion of ketamine as an opioid substitute for more than 2 days, scheduled in a drug rotation protocol. RESULTS Thirty-two children (median age 2.5 years, range 0.1-16.0; weight 11.2 kg [3.8-62.0]) were included. Patients had received continuous intravenous infusion of opioids and benzodiazepines for 16.0 days (4.0-34.0) when drug rotation was started. The median dose of continuous intravenous infusion of ketamine was 4.0 mg·kg-1·h-1 (1.8-6.0) and the median duration was 3.0 days (2.0-6.0). After having restarted opioids, fentanyl doses were significantly lower compared with the time before the drug rotation began (after, 2.9 µg·kg-1·h-1 [0.8-4.9] vs before, 4.15 µg·kg-1·h-1 [1.2-10.0]; p < 0.001). Continuous intravenous infusion of midazolam and clonidine were unchanged during drug rotation. COMFORT-B scoring was significantly lower after having started drug rotation (after, 14.5 [8-19] vs before, 16 [11-22]; p < 0.001). CONCLUSION Drug rotation with ketamine in mechanically ventilated children with opioid tolerance is feasible and seems to reduce the rate of fentanyl infusion.
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Affiliation(s)
- Felix Neunhoeffer
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany.
| | - Anja Hanser
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
| | - Martin Esslinger
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
| | - Vanja Icheva
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
| | - Matthias Kumpf
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
| | - Ines Gerbig
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
| | - Michael Hofbeck
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
| | - Jörg Michel
- Department of Paediatric Cardiology, Pulmology and Intensive Care Medicine, University Children's Hospital Tübingen, Hoppe-Seyler Str. 1, 72076, Tübingen, Germany
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17
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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: 86] [Impact Index Per Article: 12.3] [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.
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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.)
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18
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Wu L, Zhang S, Shkhyan R, Lee S, Gullo F, Eliasberg CD, Petrigliano FA, Ba K, Wang J, Lin Y, Evseenko D. Kappa opioid receptor signaling protects cartilage tissue against posttraumatic degeneration. JCI Insight 2017; 2:e88553. [PMID: 28097228 DOI: 10.1172/jci.insight.88553] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Osteoarthritis is the most common form of arthritis, and pain relief with opioid-like drugs is a commonly used therapeutic for osteoarthritic patients. Recent studies published by our group showed that the kappa opioid receptor (KOR) is highly expressed during human development in joint-forming cells. However, the precise role of this receptor in the skeletal system remains elusive. The main aim of the current study was to investigate the role of KOR signaling in synovial and cartilaginous tissues in pathological conditions. Our data demonstrate that KOR null mice exhibit accelerated cartilage degeneration after injury when compared with WT mice. Activation of KOR signaling increased the expression of anabolic enzymes and inhibited cartilage catabolism and degeneration in response to proinflammatory cytokines such as TNF-α. In addition, selective KOR agonists increased joint lubrication via the activation of cAMP/CREB signaling in chondrocytes and synovial cells. Taken together, these results demonstrate direct effects of KOR agonists on cartilage and synovial cells and reveals a protective effect of KOR signaling against cartilage degeneration after injury. In addition to pain control, local administration of dynorphin or other KOR agonist represents an attractive therapeutic approach in patients with early stages of osteoarthritis.
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Affiliation(s)
- Ling Wu
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Shu Zhang
- State Key Laboratory for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China
| | - Ruzanna Shkhyan
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Siyoung Lee
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Francesca Gullo
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Claire D Eliasberg
- Department of Orthopaedic Surgery, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Frank A Petrigliano
- Department of Orthopaedic Surgery, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Kai Ba
- State Key Laboratory for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China
| | - Jing Wang
- Department of Stomatology, Tenth People's Hospital of Tongji University, Shanghai, China
| | - Yunfeng Lin
- State Key Laboratory for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China
| | - Denis Evseenko
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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19
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Chan P, Lutfy K. Molecular Changes in Opioid Addiction: The Role of Adenylyl Cyclase and cAMP/PKA System. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 137:203-27. [PMID: 26810003 DOI: 10.1016/bs.pmbts.2015.10.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
For centuries, opiate analgesics have had a considerable presence in the treatment of moderate to severe pain. While effective in providing analgesia, opiates are notorious in exerting many undesirable adverse reactions. The receptor targets and the intracellular effectors of opioids have largely been identified. Furthermore, much of the mechanisms underlying the development of tolerance, dependence, and withdrawal have been delineated. Thus, there is a focus on developing novel compounds or strategies in mitigating or avoiding the development of tolerance, dependence, and withdrawal. This review focuses on the adenylyl cyclase and cyclic adenosine 3,5-monophosphate (cAMP)/protein kinase A (AC/cAMP/PKA) system as the central player in mediating the acute and chronic effects of opioids. This chapter also reviews the neuronal adaptive changes in the locus coeruleus, amygdala, periaqueductal gray, and ventral tegmental area induced by acute and chronic actions of opioid because these neuronal adaptive changes in these regions may underlie the behavioral changes observed in opiate users and abusers.
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Affiliation(s)
- Patrick Chan
- Department of Pharmacy and Pharmacy Administration, Western University of Health Sciences, College of Pharmacy, Pomona, California, USA.
| | - Kabirullah Lutfy
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, California, USA
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20
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Abstract
Acute pain management remains a challenge in opioid dependent patients, and it has been recognised that these patients are commonly under-treated.Chronic opioid exposure leads to widespread adaptations both at cellular and synaptic level.Physical dependence is a neuropharmacological phenomenon as a result of neuroadaptation and neuroplasticity, in contrast to addiction that is both neuropharmacological and behavioural.While providing the patient's pre-existing opioid requirement, the acute pain episode should be managed using additional multimodal analgesia: non-opioid medications in combination with local anaesthetic techniques and as required, short-acting opioid titrated to effect.Patients on long term buprenorphine and methadone with acute pain episode should be continued with their maintenance therapy and an additional short-acting opioid analgesic titrated to achieve therapeutic effect.
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Affiliation(s)
- Vivek Mehta
- Consultants in Pain Medicine and Anaesthesia, Pain and Anaesthesia Research Centre, St Bartholomew's Hospital. Barts and The London NHS Trust, London, UK
| | - Richard Langford
- Consultants in Pain Medicine and Anaesthesia, Pain and Anaesthesia Research Centre, St Bartholomew's Hospital. Barts and The London NHS Trust, London, UK
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21
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Brust TF, Conley JM, Watts VJ. Gα(i/o)-coupled receptor-mediated sensitization of adenylyl cyclase: 40 years later. Eur J Pharmacol 2015; 763:223-32. [PMID: 25981304 DOI: 10.1016/j.ejphar.2015.05.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/02/2015] [Accepted: 05/11/2015] [Indexed: 12/20/2022]
Abstract
Heterologous sensitization of adenylyl cyclase (also referred to as superactivation, sensitization, or supersensitization of adenylyl cyclase) is a cellular adaptive response first described 40 years ago in the laboratory of Dr. Marshall Nirenberg. This apparently paradoxical cellular response occurs following persistent activation of Gαi/o-coupled receptors and causes marked enhancement in the activity of adenylyl cyclases, thereby increasing cAMP production. Since our last review in 2005, significant progress in the field has led to a better understanding of the relevance of, and the cellular biochemical processes that occur during the development and expression of heterologous sensitization. In this review we will discuss the recent advancements in the field and the mechanistic hypotheses on heterologous sensitization.
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Affiliation(s)
- Tarsis F Brust
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Jason M Conley
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA.
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22
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Bagley EE. Opioid and GABAB receptors differentially couple to an adenylyl cyclase/protein kinase A downstream effector after chronic morphine treatment. Front Pharmacol 2014; 5:148. [PMID: 25009497 PMCID: PMC4067908 DOI: 10.3389/fphar.2014.00148] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 06/03/2014] [Indexed: 01/18/2023] Open
Abstract
Opioids are intensely addictive, and cessation of their chronic use is associated with a highly aversive withdrawal syndrome. A cellular hallmark of withdrawal is an opioid sensitive protein kinase A-dependent increase in GABA transporter-1 (GAT-1) currents in periaqueductal gray (PAG) neurons. Elevated GAT-1 activity directly increases GABAergic neuronal excitability and synaptic GABA release, which will enhance GABAergic inhibition of PAG output neurons. This reduced activity of PAG output neurons to several brain regions, including the hypothalamus and medulla, contributes to many of the PAG-mediated signs of opioid withdrawal. The GABAB receptor agonist baclofen reduces some of the PAG mediated signs of opioid withdrawal. Like the opioid receptors the GABAB receptor is a Gi/Go coupled G-protein coupled receptor. This suggests it could be modulating GAT-1 activity in PAG neurons through its inhibition of the adenylyl cyclase/protein kinase A pathway. Opioid modulation of the GAT-1 activity can be detected by changes in the reversal potential of opioid membrane currents. We found that when opioids are reducing the GAT-1 cation conductance and increasing the GIRK conductance the opioid agonist reversal potential is much more negative than Ek. Using this approach for GABAB receptors we show that the GABAB receptor agonist, baclofen, does not couple to inhibition of GAT-1 currents during opioid withdrawal. It is possible this differential signaling of the two Gi/Go coupled G-protein coupled receptors is due to the strong compartmentalization of the GABAB receptor that does not favor signaling to the adenylyl cyclase/protein kinase A/GAT-1 pathway. This highlights the importance of studying the effects of G-protein coupled receptors in native tissue with endogenous G-protein coupled receptors and the full complement of relevant proteins and signaling molecules. This study suggests that baclofen reduces opioid withdrawal symptoms through a non-GAT-1 effector.
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Affiliation(s)
- Elena E Bagley
- Discipline of Pharmacology, Sydney Medical School, University of Sydney Sydney, NSW, Australia
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23
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Bajo M, Madamba SG, Roberto M, Siggins GR. Acute morphine alters GABAergic transmission in the central amygdala during naloxone-precipitated morphine withdrawal: role of cyclic AMP. Front Integr Neurosci 2014; 8:45. [PMID: 24926240 PMCID: PMC4044973 DOI: 10.3389/fnint.2014.00045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 05/14/2014] [Indexed: 01/23/2023] Open
Abstract
The central amygdala (CeA) plays an important role in opioid addiction. Therefore, we examined the effects of naloxone-precipitated morphine withdrawal (WD) on GABAergic transmission in rat CeA neurons using whole-cell recordings with naloxone in the bath. The basal frequency of miniature inhibitory postsynaptic currents (mIPSCs) increased in CeA neurons from WD compared to placebo rats. Acute morphine (10 μ M) had mixed effects (≥20% change from baseline) on mIPSCs in placebo and WD rats. In most CeA neurons (64%) from placebo rats, morphine significantly decreased mIPSC frequency and amplitude. In 32% of placebo neurons, morphine significantly increased mIPSC amplitudes but had no effect on mIPSC frequency. In WD rats, acute morphine significantly increased mIPSC frequency but had no effect on mIPSC amplitude in 41% of CeA neurons. In 45% of cells, acute morphine significantly decreased mIPSC frequency and amplitude. Pre-treatment with the cyclic AMP inhibitor (R)-adenosine, cyclic 3',5'-(hydrogenphosphorothioate) triethylammonium (RP), prevented acute morphine-induced potentiation of mIPSCs. Pre-treatment of slices with the Gi/o G-protein subunit inhibitor pertussis toxin (PTX) did not prevent the acute morphine-induced enhancement or inhibition of mIPSCs. PTX and RP decreased basal mIPSC frequencies and amplitudes only in WD rats. The results suggest that inhibition of GABAergic transmission in the CeA by acute morphine is mediated by PTX-insensitive mechanisms, although PTX-sensitive mechanisms cannot be ruled out for non-morphine responsive cells; by contrast, potentiation of GABAergic transmission is mediated by activated cAMP signaling that also mediates the increased basal GABAergic transmission in WD rats. Our data indicate that during the acute phase of WD, the CeA opioid and GABAergic systems undergo neuroadaptative changes conditioned by a previous chronic morphine exposure and dependence.
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Affiliation(s)
- Michal Bajo
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - Samuel G Madamba
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - Marisa Roberto
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - George R Siggins
- Department of Molecular and Cellular Neuroscience, The Scripps Research Institute La Jolla, CA, USA
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Conley JM, Brust TF, Xu R, Burris KD, Watts VJ. Drug-induced sensitization of adenylyl cyclase: assay streamlining and miniaturization for small molecule and siRNA screening applications. J Vis Exp 2014:e51218. [PMID: 24514897 DOI: 10.3791/51218] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Sensitization of adenylyl cyclase (AC) signaling has been implicated in a variety of neuropsychiatric and neurologic disorders including substance abuse and Parkinson's disease. Acute activation of Gαi/o-linked receptors inhibits AC activity, whereas persistent activation of these receptors results in heterologous sensitization of AC and increased levels of intracellular cAMP. Previous studies have demonstrated that this enhancement of AC responsiveness is observed both in vitro and in vivo following the chronic activation of several types of Gαi/o-linked receptors including D2 dopamine and μ opioid receptors. Although heterologous sensitization of AC was first reported four decades ago, the mechanism(s) that underlie this phenomenon remain largely unknown. The lack of mechanistic data presumably reflects the complexity involved with this adaptive response, suggesting that nonbiased approaches could aid in identifying the molecular pathways involved in heterologous sensitization of AC. Previous studies have implicated kinase and Gbγ signaling as overlapping components that regulate the heterologous sensitization of AC. To identify unique and additional overlapping targets associated with sensitization of AC, the development and validation of a scalable cAMP sensitization assay is required for greater throughput. Previous approaches to study sensitization are generally cumbersome involving continuous cell culture maintenance as well as a complex methodology for measuring cAMP accumulation that involves multiple wash steps. Thus, the development of a robust cell-based assay that can be used for high throughput screening (HTS) in a 384 well format would facilitate future studies. Using two D2 dopamine receptor cellular models (i.e. CHO-D2L and HEK-AC6/D2L), we have converted our 48-well sensitization assay (>20 steps 4-5 days) to a five-step, single day assay in 384-well format. This new format is amenable to small molecule screening, and we demonstrate that this assay design can also be readily used for reverse transfection of siRNA in anticipation of targeted siRNA library screening.
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Affiliation(s)
- Jason M Conley
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University
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25
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Maiellaro I, Lefkimmiatis K, Moyer MP, Curci S, Hofer AM. Termination and activation of store-operated cyclic AMP production. J Cell Mol Med 2014; 16:2715-25. [PMID: 22681560 PMCID: PMC3470754 DOI: 10.1111/j.1582-4934.2012.01592.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Diverse pathophysiological processes (e.g. obesity, lifespan determination, addiction and male fertility) have been linked to the expression of specific isoforms of the adenylyl cyclases (AC1-AC10), the enzymes that generate cyclic AMP (cAMP). Our laboratory recently discovered a new mode of cAMP production, prominent in certain cell types, that is stimulated by any manoeuvre causing reduction of free [Ca2+] within the lumen of the endoplasmic reticulum (ER) calcium store. Activation of this ‘store-operated’ pathway requires the ER Ca2+ sensor, STIM1, but the identity of the enzymes responsible for cAMP production and how this process is regulated is unknown. Here, we used sensitive FRET-based sensors for cAMP in single cells combined with silencing and overexpression approaches to show that store-operated cAMP production occurred preferentially via the isoform AC3 in NCM460 colonic epithelial cells. Ca2+ entry via the plasma membrane Ca2+ channel, Orai1, suppressed cAMP production, independent of store refilling. These findings are an important first step towards defining the functional significance and to identify the protein composition of this novel Ca2+/cAMP crosstalk system.
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Affiliation(s)
- Isabella Maiellaro
- VA Boston Healthcare System, Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, West Roxbury, MA 02132, USA
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26
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Skrabalova J, Drastichova Z, Novotny J. Morphine as a Potential Oxidative Stress-Causing Agent. MINI-REV ORG CHEM 2013; 10:367-372. [PMID: 24376392 PMCID: PMC3871421 DOI: 10.2174/1570193x113106660031] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 05/03/2013] [Accepted: 05/03/2013] [Indexed: 12/21/2022]
Abstract
Morphine exhibits important pharmacological effects for which it has been used in medical practice for quite a long time. However, it has a high addictive potential and can be abused. Long-term use of this drug can be connected with some pathological consequences including neurotoxicity and neuronal dysfunction, hepatotoxicity, kidney dysfunction, oxidative stress and apoptosis. Therefore, most studies examining the impact of morphine have been aimed at determining the effects induced by chronic morphine exposure in the brain, liver, cardiovascular system and macrophages. It appears that different tissues may respond to morphine diversely and are distinctly susceptible to oxidative stress and subsequent oxidative damage of biomolecules. Importantly, production of reactive oxygen/nitrogen species induced by morphine, which have been observed under different experimental conditions, can contribute to some pathological processes, degenerative diseases and organ dysfunctions occurring in morphine abusers or morphine-treated patients. This review attempts to provide insights into the possible relationship between morphine actions and oxidative stress.
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Affiliation(s)
- Jitka Skrabalova
- Department of Physiology, Faculty of Science, Charles University in Prague, Czech Republic
| | - Zdenka Drastichova
- Department of Physiology, Faculty of Science, Charles University in Prague, Czech Republic
| | - Jiri Novotny
- Department of Physiology, Faculty of Science, Charles University in Prague, Czech Republic
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27
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Corder G, Doolen S, Donahue RR, Winter MK, Jutras BL, He Y, Hu X, Wieskopf JS, Mogil JS, Storm DR, Wang ZJ, McCarson KE, Taylor BK. Constitutive μ-opioid receptor activity leads to long-term endogenous analgesia and dependence. Science 2013; 341:1394-9. [PMID: 24052307 DOI: 10.1126/science.1239403] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Opioid receptor antagonists increase hyperalgesia in humans and animals, which indicates that endogenous activation of opioid receptors provides relief from acute pain; however, the mechanisms of long-term opioid inhibition of pathological pain have remained elusive. We found that tissue injury produced μ-opioid receptor (MOR) constitutive activity (MOR(CA)) that repressed spinal nociceptive signaling for months. Pharmacological blockade during the posthyperalgesia state with MOR inverse agonists reinstated central pain sensitization and precipitated hallmarks of opioid withdrawal (including adenosine 3',5'-monophosphate overshoot and hyperalgesia) that required N-methyl-D-aspartate receptor activation of adenylyl cyclase type 1. Thus, MOR(CA) initiates both analgesic signaling and a compensatory opponent process that generates endogenous opioid dependence. Tonic MOR(CA) suppression of withdrawal hyperalgesia may prevent the transition from acute to chronic pain.
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Affiliation(s)
- G Corder
- Department of Physiology, University of Kentucky, Lexington, KY 40536, USA
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28
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Zhang L, Loh HH, Law PY. A novel noncanonical signaling pathway for the μ-opioid receptor. Mol Pharmacol 2013; 84:844-53. [PMID: 24061856 DOI: 10.1124/mol.113.088278] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The µ-opioid receptor (OPRM1) signals as a classic G protein-coupled receptor by activating heterotrimeric Gi/Go proteins resulting in adenylyl cyclase (AC) inhibition. Such AC inhibition is desensitized after prolonged agonist treatment. However, after receptor desensitization, the intracellular cAMP level remains regulated by OPRM1, as demonstrated by the intracellular cAMP level increase or AC superactivation upon removal of an agonist or addition of an antagonist. We now demonstrate that such intracellular cAMP regulation is mediated by a novel noncanonical signaling pathway resulting from OPRM1 being converted to a receptor tyrosine kinase (RTK)-like entity. This noncanonical OPRM1 signaling is initiated by the receptor recruiting and activating Src kinase within the receptor complex, leading to phosphorylation of the OPRM1 Tyr(336) residue. Phospho-Tyr(336) serves as the docking site for growth factor receptor-bound protein/son of sevenless, leading to the recruitment and activation of the Ras/Raf-1 and subsequent phosphorylation and activation of AC5/6 by Raf-1. Such sequence of events was established by the absence of Ras/Raf1 recruitment and activation by the OPRM1-Y336F mutant, by the presence of Src kinase inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2) or the absence of Src activity, by the presence of specific Raf-1 inhibitor GW5074 (5-iodo-3-[(3,5-dibromo-4-hydroxyphenyl) methylene]-2-indolinone) or the absence of Raf-1, or by the dominant negative RasN17 mutant. Src together with Ras activates Raf1 which was established by the inability of the Raf1-Tyr(340/341) mutant to activate AC. Hence, the phosphorylation of OPRM1 at Tyr(336) by Src serves as the trigger for the conversion of a classic Gi/Go-coupled receptor into an RTK-like entity, resulting in a noncanonical pathway even after the original Gi/Go signals are blunted.
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Affiliation(s)
- Lei Zhang
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota
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29
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Knapman A, Abogadie F, McIntrye P, Connor M. A real-time, fluorescence-based assay for measuring μ-opioid receptor modulation of adenylyl cyclase activity in Chinese hamster ovary cells. ACTA ACUST UNITED AC 2013; 19:223-31. [PMID: 23989451 DOI: 10.1177/1087057113501391] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inhibition of adenylyl cyclase (AC) activity is frequently used to measure µ-opioid receptor (MOR) activation. We sought to develop a simple, rapid assay of AC activity in whole cells that could be used to study MOR signaling. Chinese hamster ovary cells expressing human MOR (CHO-MOR cells) were grown in 96-well plates and loaded with membrane potential-sensitive fluorescent dye. CHO-MOR cells were treated with the AC activator forskolin (FSK), with or without simultaneous application of MOR agonists, and the resulting change in fluorescence was measured. CHO-MOR cells hyperpolarized in response to application of FSK (pEC₅₀, 7.3) or calcitonin (pEC₅₀, 9.4). A submaximally effective concentration of FSK (300 nM) caused a 52% ± 2% decrease in fluorescence. Simultaneous application of the opioids DAMGO (pEC₅₀, 7.4; E(max), 56%), morphine (pEC₅₀, 7.0; E(max), 61%); and buprenorphine (pEC₅₀, 8.6; E(max), 24%) inhibited the FSK response in a dose-dependent manner while having no effect by themselves. The effects of DAMGO were blocked by pertussis toxin. This assay represents a simple, robust method for real-time observation of AC inhibition by MOR in CHO cells. It represents an appealing alternative to end-point assays that rely on cAMP accumulation and can avoid potential confounds associated with rapid desensitization of MOR signaling.
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Affiliation(s)
- Alisa Knapman
- 1Australian School of Advanced Medicine, Macquarie University, NSW Australia
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30
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Javadi S, Ejtemaeimehr S, Keyvanfar HR, Moghaddas P, Aminian A, Rajabzadeh A, Mani AR, Dehpour AR. Pioglitazone potentiates development of morphine-dependence in mice: possible role of NO/cGMP pathway. Brain Res 2013; 1510:22-37. [PMID: 23399681 DOI: 10.1016/j.brainres.2012.12.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 11/15/2012] [Accepted: 12/13/2012] [Indexed: 01/23/2023]
Abstract
Peroxizome proliferator-activated receptor gamma (PPARγ) is highly expressed in the central nervous system where it modulates numerous gene transcriptions. Nitric oxide synthase (NOS) expression could be modified by simulation of PPARγ which in turn activates nitric oxide (NO)/soluble guanylyl-cyclase (sGC)/cyclic guanosine mono phosphate (cGMP) pathway. It is well known that NO/cGMP pathway possesses pivotal role in the development of opioid dependence and this study is aimed to investigate the effect of PPARγ stimulation on opioid dependence in mice as well as human glioblastoma cell line. Pioglitazone potentiated naloxone-induced withdrawal syndrome in morphine dependent mice in vivo. While selective inhibition of PPARγ, neuronal NOS or GC could reverse the pioglitazone-induced potentiation of morphine withdrawal signs; sildenafil, a phosphodiesterase-5 inhibitor amplified its effect. We also showed that nitrite levels in the hippocampus were significantly elevated in pioglitazone-treated morphine dependent mice. In the human glioblastoma (U87) cell line, rendered dependent to morphine, cAMP levels did not show any alteration after chronic pioglitazone administration while cGMP measurement revealed a significant rise. We were unable to show a significant alteration in neuronal NOS mRNA expressions by pioglitazone in mice hippocampus or U87 cells. Our results suggest that pioglitazone has the ability to enhance morphine-dependence and to augment morphine withdrawal signs. The possible pathway underlying this effect is through activation of NO/GC/cGMP pathway.
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Affiliation(s)
- Shiva Javadi
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran
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31
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Zheng H, Loh HH, Law PY. Posttranslation modification of G protein-coupled receptor in relationship to biased agonism. Methods Enzymol 2013; 522:391-408. [PMID: 23374194 DOI: 10.1016/b978-0-12-407865-9.00018-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Biased signaling has been reported with a series of G protein-coupled receptors (GPCRs), including β(2)-adrenergic receptor and μ-opioid receptor (OPRM1). The concept of biased signaling suggests that the agonists of one particular receptor may activate the downstream signaling pathways with different efficacies. Thus in an extreme case, agonists might activate different sets of signaling pathways, which provide a new route to develop drugs with increased efficacies and decreased side effects. Among the many factors, posttranslation modifications of receptor proteins have major roles in influencing the biased signaling. Take OPRM1, for example, the phosphorylation and palmitoylation of receptor can regulate the biased signaling induced by agonists. Thus, by modulating these posttranslation modifications, the biased signaling of GPCRs can be regulated. In addition, although it is not considered as posttranslation modification normally, the distribution of GPCRs on cell membrane, especially the distribution between lipid-raft and non-raft microdomains, also contributes to the biased signaling. Thus in this chapter, we described the methods used in our laboratory to study receptor phosphorylation, receptor palmitoylation, and membrane distribution of receptor by using OPRM1 as a model. A functional model was also provided on these posttranslational modifications at the last section of this chapter.
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Affiliation(s)
- Hui Zheng
- Stem Cell and Cancer Biology Group, Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
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32
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Zhao H, Wu G, Cao X. EGFR dependent subcellular communication was responsible for morphine mediated AC superactivation. Cell Signal 2012; 25:417-28. [PMID: 23142605 DOI: 10.1016/j.cellsig.2012.10.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 10/01/2012] [Accepted: 10/01/2012] [Indexed: 10/27/2022]
Abstract
Compensatory adenylyl cyclase (AC) superactivation has been postulated to be responsible for the development of morphine tolerance and dependence, the underlying mechanism was demonstrated to comprise c-Src-dependent upregulation of AC5 within the lipid rafts. In the present study, we demonstrated that chronic morphine treatment sensitized EGFR signaling by augmenting EGFR phosphorylation and translocation into ER, which was essential for CRT-MOR tethering within the lipid rafts and AC5 superactivation. Intriguingly, synaptic clustering of CRT-MOR was dependent on EGFR phosphorylation and presumed to implicate in alignment and organization of synaptic compartments. Taken together, our data raised the possibility that an adaptive change in MOR and EGFR signal systems might establish CRT related subcellular communication, the signaling network within brain synaptic zone was proposed to implicate in morphine tolerance and dependence.
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Affiliation(s)
- Hui Zhao
- Department of Integrative Medicine and Neurobiology, National Key lab of Medical Neurobiology, Institute of Brain Research Sciences, Shanghai Medical College, Fudan University, PR China.
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33
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Zhao YL, Chen SR, Chen H, Pan HL. Chronic opioid potentiates presynaptic but impairs postsynaptic N-methyl-D-aspartic acid receptor activity in spinal cords: implications for opioid hyperalgesia and tolerance. J Biol Chem 2012; 287:25073-85. [PMID: 22679016 DOI: 10.1074/jbc.m112.378737] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Opioids are the most effective analgesics for the treatment of moderate to severe pain. However, chronic opioid treatment can cause both hyperalgesia and analgesic tolerance, which limit their clinical efficacy. In this study, we determined the role of pre- and postsynaptic NMDA receptors (NMDARs) in controlling increased glutamatergic input in the spinal cord induced by chronic systemic morphine administration. Whole-cell voltage clamp recordings of excitatory postsynaptic currents (EPSCs) were performed on dorsal horn neurons in rat spinal cord slices. Chronic morphine significantly increased the amplitude of monosynaptic EPSCs evoked from the dorsal root and the frequency of spontaneous EPSCs, and these changes were largely attenuated by blocking NMDARs and by inhibiting PKC, but not PKA. Also, blocking NR2A- or NR2B-containing NMDARs significantly reduced the frequency of spontaneous EPSCs and the amplitude of evoked EPSCs in morphine-treated rats. Strikingly, morphine treatment largely decreased the amplitude of evoked NMDAR-EPSCs and NMDAR currents of dorsal horn neurons elicited by puff NMDA application. The reduction in postsynaptic NMDAR currents caused by morphine was prevented by resiniferatoxin pretreatment to ablate TRPV1-expressing primary afferents. Furthermore, intrathecal injection of the NMDAR antagonist significantly attenuated the development of analgesic tolerance and the reduction in nociceptive thresholds induced by chronic morphine. Collectively, our findings indicate that chronic opioid treatment potentiates presynaptic, but impairs postsynaptic, NMDAR activity in the spinal cord. PKC-mediated increases in NMDAR activity at nociceptive primary afferent terminals in the spinal cord contribute critically to the development of opioid hyperalgesia and analgesic tolerance.
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Affiliation(s)
- Yi-Lin Zhao
- Center for Pain and Neuroscience Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
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Seyedabadi M, Ostad SN, Albert PR, Dehpour AR, Rahimian R, Ghazi-Khansari M, Ghahremani MH. Ser/ Thr residues at α3/β5 loop of Gαs are important in morphine-induced adenylyl cyclase sensitization but not mitogen-activated protein kinase phosphorylation. FEBS J 2012; 279:650-60. [PMID: 22177524 DOI: 10.1111/j.1742-4658.2011.08459.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The signaling switch of β2-adrenergic and μ(1) -opioid receptors from stimulatory G-protein (G(αs) ) to inhibitory G-protein (G(αi) ) (and vice versa) influences adenylyl cyclase (AC) and extracellular-regulated kinase (ERK)1/2 activation. Post-translational modifications, including dephosphorylation of G(αs) , enhance opioid receptor coupling to G(αs) . In the present study, we substituted the Ser/Thr residues of G(αs) at the α3/β5 and α4/β6 loops aiming to study the role of G(αs) lacking Ser/Thr phosphorylation with respect to AC sensitization and mitogen-activated protein kinase activation. Isoproterenol increased the cAMP concentration (EC(50) = 22.8 ± 3.4 μm) in G(αs) -transfected S49 cyc- cells but not in nontransfected cells. However, there was no significant difference between the G(αs) -wild-type (wt) and mutants. Morphine (10 μm) inhibited AC activity more efficiently in cyc- compared to G(αs) -wt introduced cells (P < 0.05); however, we did not find a notable difference between G(αs) -wt and mutants. Interestingly, G(αs) -wt transfected cells showed more sensitization with respect to AC after chronic morphine compared to nontransfected cells (101 ± 12% versus 34 ± 6%; P < 0.001); μ1-opioid receptor interacted with G(αs) , and both co-immunoprecipitated after chronic morphine exposure. Furthermore, mutation of T270A and S272A (P < 0.01), as well as T270A, S272A and S261A (P < 0.05), in α3/β5, resulted in a higher level of AC supersensitization. ERK1/2 phosphorylation was rapidly induced by isoproterenol (by 9.5 ± 2.4-fold) and morphine (22 ± 2.2-fold) in G(αs) -transfected cells; mutations of α3/β5 and α4/β6 did not affect the pattern or extent of mitogen-activated protein kinase activation. The findings of the present study show that G(αs) interacts with the μ1-opioid receptor, and the Ser/Thr mutation to Ala at the α3/β5 loop of G(αs) enhances morphine-induced AC sensitization. In addition, G(αs) was required for the rapid phosphorylation of ERK1/2 by isoproterenol but not morphine.
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Affiliation(s)
- Mohammad Seyedabadi
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Iran
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35
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Mizuta K, Zhang Y, Xu D, Masaki E, Panettieri RA, Emala CW. The dopamine D(2) receptor is expressed and sensitizes adenylyl cyclase activity in airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2011; 302:L316-24. [PMID: 21964403 DOI: 10.1152/ajplung.00130.2011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Dopamine receptors are G protein-coupled receptors that are divided into two subgroups, "D(1)-like" receptors (D(1) and D(5)) that couple to the G(s) protein and "D(2)-like" receptors (D(2), D(3), and D(4)) that couple to G(i). Although inhaled dopamine has been reported to induce bronchodilation in patients with asthma, functional expression of dopamine receptor subtypes has never been described on airway smooth muscle (ASM) cells. Acute activation of G(i)-coupled receptors inhibits adenylyl cyclase activity and cAMP synthesis, which classically impairs ASM relaxation. In contrast, chronic activation of G(i)-coupled receptors produces a paradoxical enhancement of adenylyl cyclase activity referred to as heterologous sensitization. We questioned whether the dopamine D(2)-like receptor is expressed on ASM, whether it exhibits classical G(i)-coupling, and whether it modulates ASM function. We detected the mRNA encoding the dopamine D(2) receptor in total RNA isolated from native human ASM and from cultured human airway smooth muscle (HASM) cells. Immunoblots identified the dopamine D(2) receptor protein in both native human and guinea pig ASM and cultured HASM cells. The dopamine D(2) receptor protein was immunohistochemically localized to both human and guinea pig ASM. Acute activation of the dopamine D(2) receptor by quinpirole inhibited forskolin-stimulated adenylyl cyclase activity in HASM cells, which was blocked by the dopamine D(2) receptor antagonist L-741626. In contrast, the chronic pretreatment (1 h) with quinpirole potentiated forskolin-stimulated adenylyl cyclase activity, which was inhibited by L-741626, the phospholipase C inhibitor U73122, or the protein kinase C inhibitor GF109203X. Quinpirole also stimulated inositol phosphate synthesis, which was inhibited by L-741626 or U73122. Chronic pretreatment (1 h) of the guinea pig tracheal rings with quinpirole significantly potentiated forskolin-induced airway relaxation, which was inhibited by L-741626. These results demonstrate that functional dopamine D(2) receptors are expressed on ASM and could be a novel therapeutic target for the relaxation of ASM.
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Affiliation(s)
- Kentaro Mizuta
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York, USA.
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36
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Boran AD, Chen Y, Iyengar R. Identification of new Gβγ interaction sites in adenylyl cyclase 2. Cell Signal 2011; 23:1489-95. [PMID: 21596131 PMCID: PMC3115457 DOI: 10.1016/j.cellsig.2011.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Accepted: 05/02/2011] [Indexed: 12/21/2022]
Abstract
The role of Gβγ in adenylyl cyclase (AC) signaling is complicated due to its role as a conditional activator (AC2, AC4 and AC7) and an inhibitor (AC1, AC3 and AC8). AC2 is stimulated by Gα(s) and if Gβγ is present the stimulation is synergistic. The precise mechanism of this synergistic activation is still not known. In order to further elucidate the role of Gβγ in AC2 activation by Gα(s), peptides derived from the C1 domains of AC2 were synthesized and the ability of the various peptides to regulate AC2 function was tested. Our results identify two new Gβγ-binding sites in the AC2 C1 domain, AC2 C1a 339-360 and AC2 C1b 578-602 that are involved with stimulation of AC2 by Gβγ. These two regions are different from the previously described QEHA motif in the C2 domain of AC2. Further, the recently discovered PFAHL motif was confirmed to bind and to be involved with stimulation of AC2 by Gβγ. These functional studies indicate that multiple regions of AC2 are involved in the interaction with Gβγ.
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Affiliation(s)
- Aislyn D.W. Boran
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 USA
| | - Yibang Chen
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 USA
| | - Ravi Iyengar
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 USA
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Tumati S, Roeske WR, Largent-Milnes T, Wang R, Vanderah TW, Varga EV. Sustained morphine-mediated pain sensitization and antinociceptive tolerance are blocked by intrathecal treatment with Raf-1-selective siRNA. Br J Pharmacol 2010; 161:51-64. [PMID: 20718739 DOI: 10.1111/j.1476-5381.2010.00869.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Long-term morphine treatment enhances pain neurotransmitter [such as calcitonin gene-related peptide (CGRP)] levels in the spinal cord. It has been suggested previously that increased spinal CGRP may contribute to sustained morphine-mediated paradoxical pain sensitization and antinociceptive tolerance. Previous in vitro studies from our group indicated that Raf-1 kinase-mediated adenylyl cyclase superactivation played a crucial role in sustained morphine-mediated augmentation of basal and evoked CGRP release from cultured primary sensory neurons. The present study was aimed to evaluate the physiological significance of this molecular mechanism in vivo, in rats. EXPERIMENTAL APPROACH Rats were intrathecally (i.th) injected with a Raf-1-selective small interfering RNA (siRNA) mixture for 3 days and were subsequently infused with saline or morphine, s.c. for 7 days. Thermal and mechanical sensory thresholds of the animals were assessed by daily behavioural tests. After final behavioural testing (day 6), spinal cords were isolated from each animal group and spinal CGRP and Raf-1 protein levels were measured using elisa and immunohistochemistry. KEY RESULTS Selective knockdown of spinal Raf-1 protein levels by i.th Raf-1-selective siRNA pretreatment significantly attenuated sustained morphine-mediated up-regulation of CGRP immunoreactivity in the spinal cord of rats and prevented the development of thermal hyperalgesia, mechanical allodynia and antinociceptive tolerance. CONCLUSIONS AND IMPLICATIONS Raf-1 played a significant role in sustained morphine-mediated paradoxical pain sensitization and antinociceptive tolerance in vivo. These findings suggest novel pharmacological approaches to improve the long-term utility of opioids in the treatment of chronic pain.
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Affiliation(s)
- S Tumati
- Department of Pharmacology, The University of Arizona, Tucson, AZ, USA
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Aloisi G, Silvano E, Rossi M, Millan MJ, Maggio R. Differential induction of adenylyl cyclase supersensitivity by antiparkinson drugs acting as agonists at dopamine D1/D2/D3 receptors vs D2/D3 receptors only: parallel observations from co-transfected human and native cerebral receptors. Neuropharmacology 2010; 60:439-45. [PMID: 21035472 DOI: 10.1016/j.neuropharm.2010.10.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 10/14/2010] [Accepted: 10/20/2010] [Indexed: 10/18/2022]
Abstract
Though there is evidence that sustained exposure of dopamine (DA) receptors to agonists can elicit a supersensitivity of adenylyl cyclase (AC), little is known about the pharmacological characteristics of this phenomenon, and possible interrelationships amongst DA receptor subtypes have not been examined. In cells co-transfected with D(1) plus D(2), or D(1) plus D(3), receptors, which are known to physically and functionally interact, long-term exposure to quinpirole, pramipexole and ropinirole (which possess negligible affinities for D(1) sites) elicited supersensitivity of D(1) receptor-activated AC. By contrast, D(2)/D(3) receptor agonists that also act as D(1) receptor agonists, bromocriptine, lisuride, cabergoline, apomorphine and DA itself, did not elicit supersensitivity. Interestingly, AC supersensitivity was also observed in the nucleus accumbens of mice pretreated with twice-daily pramipexole and quinpirole, whereas no change was seen either with lisuride or with the DA precursor, L-DOPA. Thus, AC supersensitivity is elicited by the sustained exposure of cloned human and native mouse populations of dopaminergic receptors, to D(2)/D(3) but not D(1)/D(2)/D(3) agonists. These observations may be related to the exacerbation of gambling in Parkinson's disease that is provoked by antiparkinson agents acting as selective D(2)/D(3) receptor agonists, notably pramipexole.
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Affiliation(s)
- Gabriella Aloisi
- Department of Experimental Medicine, University of L'Aquila, Via Vetoio Coppito 2, 67100 L'Aquila, Italy
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Tumati S, Roeske WR, Vanderah TW, Varga EV. Sustained morphine treatment augments prostaglandin E2-evoked calcitonin gene-related peptide release from primary sensory neurons in a PKA-dependent manner. Eur J Pharmacol 2010; 648:95-101. [PMID: 20826131 DOI: 10.1016/j.ejphar.2010.08.042] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 07/16/2010] [Accepted: 08/25/2010] [Indexed: 11/19/2022]
Abstract
Tissue damage leads to pain sensitization due to peripheral and central release of excitatory mediators such as prostaglandin E₂ (PGE₂). PGE₂ sensitizes spinal pain neurotransmitter such as calcitonin gene-related peptide (CGRP) release via activation of cyclic AMP (cAMP)/protein kinase A (PKA)-dependent signaling mechanisms. Our previous data demonstrate that sustained morphine pretreatment sensitizes adenylyl cyclase(s) (AC) toward the direct stimulator, forskolin, in cultured primary sensory neurons (AC superactivation). In the present work we investigated the hypothesis that morphine pretreatment also sensitizes ACs toward Gs-protein-coupled excitatory modulators (such as PGE₂), leading to augmented PKA-dependent CGRP release from PGE₂-stimulated primary sensory dorsal root ganglion (DRG) neurons. Our results show that sustained morphine treatment potentiated PGE₂-mediated cAMP formation and augmented PGE₂-evoked CGRP release from cultured primary sensory neurons in a PKA-dependent manner. Our data suggest that attenuation of AC superactivation in primary sensory neurons may prevent the development of opioid-induced hyperalgesia.
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Affiliation(s)
- Suneeta Tumati
- Department of Pharmacology, The University of Arizona, Tucson, AZ 85724, USA
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Abstract
Drug addiction is marked by continued drug-seeking behavior despite deleterious consequences and a heightened propensity to relapse not withstanding long, drug-free periods. The enduring nature of addiction has been hypothesized to arise from perturbations in intracellular signaling, gene expression, and brain circuitry induced by substance abuse. Ameliorating some of these aberrations should abate behavioral and neurochemical markers associated with an 'addiction phenotype'. This review summarizes data showing that protein expression and signaling through the nonreceptor activator of G-protein signaling 3 (AGS3) are altered by commonly abused substances in rat and in in-vitro addiction models. AGS3 structure and function are unrelated to the more broadly studied regulator of G-protein signaling family. Thus, the unique role of AGS3 is the focus of this review. Intriguingly, AGS3 protein changes persist into drug abstinence. Accordingly, studies probing the role of AGS3 in the neurochemistry of drug-seeking behavior and relapse are studied in detail. To illuminate this study, AGS3 structure, cellular localization, and function are covered so that an idealized AGS3-targeted pharmacotherapy can be proposed.
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Affiliation(s)
- Michael Scott Bowers
- Department of Psychiatry, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA.
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Nicotine withdrawal and kappa-opioid receptors. Psychopharmacology (Berl) 2010; 210:221-9. [PMID: 19806344 DOI: 10.1007/s00213-009-1674-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Accepted: 09/08/2009] [Indexed: 10/20/2022]
Abstract
RATIONALE The synthesis and release of dynorphin are increased in the caudate/putamen (CPU) and nucleus accumbens (NAc) of nicotine-withdrawn mice, suggesting a role in the nicotine abstinence syndrome. OBJECTIVES This study aims to investigate the consequences of enhanced dynorphinergic activity on kappa-opioid receptor (KOPr) expression, coupling, and function in CPU and NAc following chronic nicotine administration and withdrawal. METHODS Mice were injected with nicotine-free base 2 mg/kg, or saline, sc, four times daily for 14 days and experiments performed at 24, 48, and 72 h after drug discontinuation. KOPr binding and mRNA were evaluated by [(3)H]-U69,593 autoradiography and in situ hybridization. KOPr coupling and function were investigated by agonist (U69-593)-stimulated [(35)S]GTPgammaS binding autoradiography and inhibition of adenylyl cyclase activity. RESULTS KOPr binding density and mRNA in CPU and NAc were unaltered during nicotine withdrawal; however, KPOr mRNA was increased in midbrain. U69,593-stimulated [(35)S]GTPgammaS binding was attenuated in both striatal regions, especially in NAc. In NAc shell and core, stimulated [(35)S]GTPgammaS binding was significantly decreased by 24 h and further declined over the 72 h observation period. In CPU, significant changes were observed only at 72 h. Basal adenylyl cyclase activity decreased early during nicotine withdrawal and recovered by 48 h. Stimulation with U69,593 failed to inhibit adenylyl cyclase activity at all times studied. CONCLUSIONS These observations suggest that KOPr coupling and function are impaired in NAc and CPU during nicotine withdrawal, and imply receptor desensitization. KOPr desensitization might be a mechanism to ameliorate aversive behavioral symptoms, as nicotine withdrawal evolves.
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Bruchas MR, Chavkin C. Kinase cascades and ligand-directed signaling at the kappa opioid receptor. Psychopharmacology (Berl) 2010; 210:137-47. [PMID: 20401607 PMCID: PMC3671863 DOI: 10.1007/s00213-010-1806-y] [Citation(s) in RCA: 234] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2009] [Accepted: 02/15/2010] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND RATIONALE The dynorphin/kappa opioid receptor (KOR) system has been implicated as a critical component of the stress response. Stress-induced activation of dynorphin-KOR is well known to produce analgesia, and more recently, it has been implicated as a mediator of stress-induced responses including anxiety, depression, and reinstatement of drug seeking. OBJECTIVE Drugs selectively targeting specific KOR signaling pathways may prove potentially useful as therapeutic treatments for mood and addiction disorders. RESULTS KOR is a member of the seven transmembrane spanning (7TM) G-protein coupled receptor (GPCR) superfamily. KOR activation of pertussis toxin-sensitive G proteins leads to Galphai/o inhibition of adenylyl cyclase production of cAMP and releases Gbetagamma, which modulates the conductances of Ca(+2) and K(+) channels. In addition, KOR agonists activate kinase cascades including G-protein coupled Receptor Kinases (GRK) and members of the mitogen-activated protein kinase (MAPK) family: ERK1/2, p38 and JNK. Recent pharmacological data suggests that GPCRs exist as dynamic, multi-conformational protein complexes that can be directed by specific ligands towards distinct signaling pathways. Ligand-induced conformations of KOR that evoke beta-arrestin-dependent p38 MAPK activation result in aversion; whereas ligand-induced conformations that activate JNK without activating arrestin produce long-lasting inactivation of KOR signaling. CONCLUSIONS In this review, we discuss the current status of KOR signal transduction research and the data that support two novel hypotheses: (1) KOR selective partial agonists that do not efficiently activate p38 MAPK may be useful analgesics without producing the dysphoric or hallucinogenic effects of selective, highly efficacious KOR agonists and (2) KOR antagonists that do not activate JNK may be effective short-acting drugs that may promote stress-resilience.
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Affiliation(s)
- Michael R Bruchas
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
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Anand KJS, Willson DF, Berger J, Harrison R, Meert KL, Zimmerman J, Carcillo J, Newth CJL, Prodhan P, Dean JM, Nicholson C. Tolerance and withdrawal from prolonged opioid use in critically ill children. Pediatrics 2010; 125:e1208-25. [PMID: 20403936 PMCID: PMC3275643 DOI: 10.1542/peds.2009-0489] [Citation(s) in RCA: 199] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE After prolonged opioid exposure, children develop opioid-induced hyperalgesia, tolerance, and withdrawal. Strategies for prevention and management should be based on the mechanisms of opioid tolerance and withdrawal. PATIENTS AND METHODS Relevant manuscripts published in the English language were searched in Medline by using search terms "opioid," "opiate," "sedation," "analgesia," "child," "infant-newborn," "tolerance," "dependency," "withdrawal," "analgesic," "receptor," and "individual opioid drugs." Clinical and preclinical studies were reviewed for data synthesis. RESULTS Mechanisms of opioid-induced hyperalgesia and tolerance suggest important drug- and patient-related risk factors that lead to tolerance and withdrawal. Opioid tolerance occurs earlier in the younger age groups, develops commonly during critical illness, and results more frequently from prolonged intravenous infusions of short-acting opioids. Treatment options include slowly tapering opioid doses, switching to longer-acting opioids, or specifically treating the symptoms of opioid withdrawal. Novel therapies may also include blocking the mechanisms of opioid tolerance, which would enhance the safety and effectiveness of opioid analgesia. CONCLUSIONS Opioid tolerance and withdrawal occur frequently in critically ill children. Novel insights into opioid receptor physiology and cellular biochemical changes will inform scientific approaches for the use of opioid analgesia and the prevention of opioid tolerance and withdrawal.
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Affiliation(s)
- Kanwaljeet J. S. Anand
- Department of Pediatrics, Le Bonheur Children’s Hospital and University of Tennessee Health Science Center, Memphis, Tennessee
| | - Douglas F. Willson
- Department of Pediatrics & Anesthesiology, University of Virginia Children’s Hospital, Charlottesville, Virginia
| | - John Berger
- Department of Pediatrics, Children’s National Medical Center, Washington, DC
| | - Rick Harrison
- Department of Pediatrics, University of California at Los Angeles, Los Angeles, California
| | - Kathleen L. Meert
- Department of Pediatrics, Children’s Hospital of Michigan, Detroit, Michigan
| | - Jerry Zimmerman
- Department of Pediatrics, Children’s Hospital and Medical Center, Seattle, Washington
| | - Joseph Carcillo
- Department of Critical Care Medicine, Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania
| | | | - Parthak Prodhan
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - J. Michael Dean
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Carol Nicholson
- Pediatric Critical Care and Rehabilitation Program, National Center for Medical Rehabilitation Research (NCMRR), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
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Mann L, Heldman E, Bersudsky Y, Vatner SF, Ishikawa Y, Almog O, Belmaker RH, Agam G. Inhibition of specific adenylyl cyclase isoforms by lithium and carbamazepine, but not valproate, may be related to their antidepressant effect. Bipolar Disord 2009; 11:885-96. [PMID: 19922557 DOI: 10.1111/j.1399-5618.2009.00762.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVES Lithium, valproate, and carbamazepine decrease stimulated brain cyclic-AMP (cAMP) levels. Adenylyl cyclase (AC), of which there are nine membrane-bound isoforms (AC1-AC9), catalyzes the formation of cAMP. We have recently demonstrated preferential inhibition of AC5 by lithium. We now sought to determine whether carbamazepine and valproate also preferentially inhibit specific AC isoforms or decrease cAMP levels via different mechanisms. METHODS COS7 cells were transfected with one of AC1-AC9, with or without D1-dopamine receptors. Carbamazepine's and valproate's effect on forskolin- or D1 agonist-stimulated ACs was studied. The effect of Mg(2+) on lithium's inhibition was studied in membrane-enriched fraction from COS7 cells co-expressing AC5 and D1 receptors. AC5 knockout mice were tested for a behavioral phenotype similar to that of lithium treatment. RESULTS Carbamazepine preferentially inhibited forskolin-stimulated AC5 and AC1 and all D1 agonist-stimulated ACs, with AC5 and AC7 being the most sensitive. When compared to 1 or 3 mM Mg(2+), 10 mM Mg(2+) reduced lithium-induced AC5 inhibition by 70%. In silico modeling suggests that among AC isoforms carbamazepine preferentially affects AC1 and AC5 by interacting with the catechol-estrogen site. Valproate did not affect any forskolin- or D1 receptor-stimulated AC. AC5 knockout mice responded similarly to antidepressant- or lithium-treated wild-types in the forced-swim test but not in the amphetamine-induced hyperactivity mania model. CONCLUSIONS Lithium and carbamazepine preferentially inhibit AC5, albeit via different mechanisms. Lithium competes with Mg(2+), which is essential for AC activity; carbamazepine competes for AC's catechol-estrogen site. Antidepressant-like behavior of AC5 knockout mice in the forced-swim test supports the notion that AC5 inhibition is involved in the antidepressant effect of lithium and carbamazepine. The effect of lithium and carbamazepine to lower cAMP formation in AC5-rich dopaminergic brain regions suggests that D1-dopamine receptors in these regions are involved in the antidepressant effect of mood stabilizers.
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Affiliation(s)
- Liad Mann
- Department of Clinical Biochemistry, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Baclofen Inhibited the Morphine-induced Conditioned Placed Preference and Withdrawal Syndromes. Zool Res 2009. [DOI: 10.3724/sp.j.1141.2008.06621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Fan P, Jiang Z, Diamond I, Yao L. Up-regulation of AGS3 during morphine withdrawal promotes cAMP superactivation via adenylyl cyclase 5 and 7 in rat nucleus accumbens/striatal neurons. Mol Pharmacol 2009; 76:526-33. [PMID: 19549762 DOI: 10.1124/mol.109.057802] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Effective medical treatment of opiate addiction is limited by a high relapse rate in abstinent addicts. Opiate withdrawal causes cAMP superactivation, but the underlying molecular mechanisms are not clear. Recent evidence implicates an activator of G-protein signaling 3 (AGS3) in opiate addiction. We found previously that during a 10-min activation of opioid receptors, AGS3 binds G alpha(i)-GDP to promote free G betagamma stimulation of adenylyl cyclase (AC) 2 and 4, and/or inactivate G alpha(i) inhibitory function, thereby transiently enhancing cAMP-dependent protein kinase A (PKA) activity. In contrast, we report here that in nucleus accumbens/striatal neurons, morphine withdrawal induces cAMP superactivation, which requires up-regulation of AGS3. cAMP increases as a function of withdrawal time, by approximately 20% at 10 min and 75% at 5 h. However, cAMP superactivation does not require G betagamma. Instead, adenosine A2A receptor activation of G alpha(s/olf) seems to initiate cAMP superactivation and promote AGS3 up-regulation. Elevated AGS3 binds to G alpha(i) to prevent its inhibition on AC activation. Moreover, withdrawal-induced increases in cAMP/PKA activate phospholipase C and epsilon protein kinase C to further stimulate AC5 and AC7, causing cAMP superactivation. Our findings identify a critical role for AC 5 and 7 and A2A receptors for up-regulation of AGS3 in morphine withdrawal-induced cAMP superactivation.
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Affiliation(s)
- Peidong Fan
- Gilead Sciences, Inc., 3172 Porter Drive, Palo Alto, California 94304, USA
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Levitt ES, Clark MJ, Jenkins PM, Martens JR, Traynor JR. Differential effect of membrane cholesterol removal on mu- and delta-opioid receptors: a parallel comparison of acute and chronic signaling to adenylyl cyclase. J Biol Chem 2009; 284:22108-22122. [PMID: 19520863 DOI: 10.1074/jbc.m109.030411] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
According to the lipid raft theory, the plasma membrane contains small domains enriched in cholesterol and sphingolipid, which may serve as platforms to organize membrane proteins. Using methyl-beta-cyclodextrin (MbetaCD) to deplete membrane cholesterol, many G protein-coupled receptors have been shown to depend on putative lipid rafts for proper signaling. Here we examine the hypothesis that treatment of HEK293 cells stably expressing FLAG-tagged mu-opioid receptors (HEK FLAG-mu) or delta-opioid receptors (HEK FLAG-delta) with MbetaCD will reduce opioid receptor signaling to adenylyl cyclase. The ability of the mu-opioid agonist [D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin to acutely inhibit adenylyl cyclase or to cause sensitization of adenylyl cyclase following chronic treatment was attenuated with MbetaCD. These effects were due to removal of cholesterol, because replenishment of cholesterol restored [D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin responses back to control values, and were confirmed in SH-SY5Y cells endogenously expressing mu-opioid receptors. The effects of MbetaCD may be due to uncoupling of the mu receptor from G proteins but were not because of decreases in receptor number and were not mimicked by cytoskeleton disruption. In contrast to the results in HEK FLAG-mu cells, MbetaCD treatment of HEK FLAG-delta cells had no effect on acute inhibition or sensitization of adenylyl cyclase by delta-opioid agonists. The differential responses of mu- and delta-opioid agonists to cholesterol depletion suggest that mu-opioid receptors are more dependent on cholesterol for efficient signaling than delta receptors and can be partly explained by localization of mu- but not delta-opioid receptors in cholesterol- and caveolin-enriched membrane domains.
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Affiliation(s)
| | - Mary J Clark
- Department of Pharmacology, Ann Arbor, Michigan 48109
| | | | | | - John R Traynor
- Department of Pharmacology, Ann Arbor, Michigan 48109; Substance Abuse Research Center, University of Michigan, Ann Arbor, Michigan 48109
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Zhang L, Zhao H, Qiu Y, Loh HH, Law PY. Src phosphorylation of micro-receptor is responsible for the receptor switching from an inhibitory to a stimulatory signal. J Biol Chem 2008; 284:1990-2000. [PMID: 19029294 DOI: 10.1074/jbc.m807971200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recent studies have revealed that in G protein-coupled receptor signalings switching between G protein- and beta-arrestin (betaArr)-dependent pathways occurs. In the case of opioid receptors, the signal is switched from the initial inhibition of adenylyl cyclase (AC) to an increase in AC activity (AC activation) during prolonged agonist treatment. The mechanism of such AC activation has been suggested to involve the switching of G proteins activated by the receptor, phosphorylation of signaling molecules, or receptor-dependent recruitment of cellular proteins. Using protein kinase inhibitors, dominant negative mutant studies and mouse embryonic fibroblast cells isolated from Src kinase knock-out mice, we demonstrated that mu-opioid receptor (OPRM1)-mediated AC activation requires direct association and activation of Src kinase by lipid raft-located OPRM1. Such Src activation was independent of betaArr as indicated by the ability of OPRM1 to activate Src and AC after prolonged agonist treatment in mouse embryonic fibroblast cells lacking both betaArr-1 and -2. Instead the switching of OPRM1 signals was dependent on the heterotrimeric G protein, specifically Gi2 alpha-subunit. Among the Src kinase substrates, OPRM1 was phosphorylated at Tyr336 within NPXXY motif by Src during AC activation. Mutation of this Tyr residue, together with mutation of Tyr166 within the DRY motif to Phe, resulted in the complete blunting of AC activation. Thus, the recruitment and activation of Src kinase by OPRM1 during chronic agonist treatment, which eventually results in the receptor tyrosine phosphorylation, is the key for switching the opioid receptor signals from its initial AC inhibition to subsequent AC activation.
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Affiliation(s)
- Lei Zhang
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.
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Sadana R, Dessauer CW. Physiological roles for G protein-regulated adenylyl cyclase isoforms: insights from knockout and overexpression studies. Neurosignals 2008; 17:5-22. [PMID: 18948702 DOI: 10.1159/000166277] [Citation(s) in RCA: 257] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 04/22/2008] [Indexed: 01/08/2023] Open
Abstract
Cyclic AMP is a universal second messenger, produced by a family of adenylyl cyclase (AC) enzymes. The last three decades have brought a wealth of new information about the regulation of cyclic AMP production by ACs. Nine hormone-sensitive, membrane-bound AC isoforms have been identified in addition to a tenth isoform that lacks membrane spans and more closely resembles the cyanobacterial AC enzymes. New model systems for purifying and characterizing the catalytic domains of AC have led to the crystal structure of these domains and the mapping of numerous interaction sites. However, big hurdles remain in unraveling the roles of individual AC isoforms and their regulation in physiological systems. In this review we explore the latest on AC knockout and overexpression studies to better understand the roles of G protein regulation of ACs in the brain, olfactory bulb, and heart.
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Affiliation(s)
- Rachna Sadana
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
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Membrane signalling complexes: implications for development of functionally selective ligands modulating heptahelical receptor signalling. Cell Signal 2008; 21:179-85. [PMID: 18790047 DOI: 10.1016/j.cellsig.2008.08.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Accepted: 08/24/2008] [Indexed: 11/24/2022]
Abstract
Technological development has considerably changed the way in which we evaluate drug efficacy and has led to a conceptual revolution in pharmacological theory. In particular, molecular resolution assays have revealed that heptahelical receptors may adopt multiple active conformations with unique signalling properties. It is therefore becoming widely accepted that ligand ability to stabilize receptor conformations with distinct signalling profiles may allow to direct the stimulus generated by an activated receptor towards a specific signalling pathway. This capacity to induce only a subset of the ensemble of responses regulated by a given receptor has been termed "functional selectivity" (or "stimulus trafficking"), and provides the bases for a highly specific regulation of receptor signalling. Concomitant with these observations, heptahelical receptors have been shown to associate with G proteins and effectors to form multimeric arrays. These complexes are constitutively formed during protein synthesis and are targeted to the cell surface as integral signalling units. Herein we summarize evidence supporting the existence of such constitutive signalling arrays and analyze the possibility that they may constitute viable targets for developing ligands with "functional selectivity".
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