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Rugg CM, Ginder JH, Bharadwaj A, Vomer R, Dale GA, Ketterly J, Zarzour H, Amendola A, Lau BC. Perioperative Management in the Collegiate Athlete: An Integrated Approach. Sports Med Int Open 2023; 7:E1-E8. [PMID: 37101550 PMCID: PMC10125641 DOI: 10.1055/a-2051-7756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 01/26/2023] [Indexed: 04/28/2023] Open
Abstract
Collegiate athletes face rigorous physical, academic, and emotional demands. While significant attention has been paid to injury prevention among young athletes in the past two decades, orthopedic injury rates remain high among collegiate athletes, and a significant number will undergo surgical management for injuries each year. In this narrative review, we describe techniques for perioperative management of pain and stress after surgery in collegiate athletes. In particular, we outline pharmacologic and non-pharmacologic management of surgical pain, with a goal of minimizing opiate consumption. We emphasize a multi-disciplinary approach to optimizing post-operative recovery in collegiate athletes help minimize reliance on opiate pain medication. Additionally, we recommend that institutional resources should be harnessed to support athletes in their well-being, from a nutritional, psychological and sleep standpoint. Critical to success in perioperative pain management is the communication among the athletic medicine team members and with the athlete and family to address pain and stress management and encourage timely, safe return to play.
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Affiliation(s)
| | | | | | - Rock Vomer
- Orthopedics, Division of Sports Medicine, Duke University, Durham,
United States
| | | | | | - Hap Zarzour
- Athletics, Duke University, Durham, United States
| | | | - Brian C. Lau
- Orthopedics, Duke University, Durham, United States
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Vijayvargiya P, Breen-Lyles M, Nord SL, Maselli D, Busciglio I, Boinpally R, Muslin A, Carrothers TJ, Camilleri M. Safety and Efficacy of Eluxadoline in Patients with Irritable Bowel Syndrome-Diarrhea With or Without Bile Acid Diarrhea: Open-Label Study. Dig Dis Sci 2022; 67:3911-3921. [PMID: 35122592 DOI: 10.1007/s10620-022-07379-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/04/2021] [Indexed: 12/28/2022]
Abstract
BACKGROUND Eluxadoline, a peripherally acting, mixed µ- and κ-opioid receptor (OR) agonist and δ-OR antagonist, is approved for treatment of adults with irritable bowel syndrome-diarrhea (IBS-D). About a third of IBS-D patients has bile acid diarrhea (BAD); opioids may stimulate TGR5 (bile acid) receptors. AIM To evaluate eluxadoline's efficacy on altered bowel functions and safety in IBS-D patients with or without BAD. METHODS In a single-center, phase 4, parallel-group, open-label study, patients with IBS-D (cohort 1) and patients with BAD were treated with eluxadoline, 100 mg tablets BID, with food for 4 weeks. Patients recorded bowel functions by electronic daily diary. BAD was based on fasting serum 7αC4 (> 52.5 ng/mL) or concurrent criteria of increased total or primary fecal BAs excreted in 48 h. We assessed efficacy on treatment compared to baseline in the two cohorts. Primary outcome measures were changes from baseline in average stool consistency Bristol Stool Form Scale (BSFS) score (range 1-7) and safety. RESULTS Mean changes from baseline in cohorts 1 and 2 (data presented in this order) were similar for: BSFS score averaged over 4 weeks' treatment (- 1.25 and - 1.09); daily bowel movement frequency (- 1.48 and - 0.79); daily urgent bowel movements (- 0.52 and - 0.80); IBS-QoL (5.9 and 13.6); serum 7αC4 (- 5.59 and - 8.78 ng/mL). There were no deaths, serious treatment-emergent adverse events, or discontinuations due to adverse events during the study. CONCLUSION Eluxadoline is similarly efficacious in the treatment of IBS-D and BAD, and it appears to be safe and efficacious as documented in large clinical trials.
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Affiliation(s)
- Priya Vijayvargiya
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA
| | - Margaret Breen-Lyles
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA
| | - Sara Linker Nord
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA
| | - Daniel Maselli
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA
| | - Irene Busciglio
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA
| | - Ramesh Boinpally
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA.,AbbVie Inc, Madison, NJ, USA
| | - Anna Muslin
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA.,AbbVie Inc, Madison, NJ, USA
| | | | - Michael Camilleri
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First St. S.W., Charlton Building, Rm. 8-110, Rochester, MN, 55905, USA.
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3
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Jaramillo-Polanco J, Lopez-Lopez C, Yu Y, Neary E, Hegron A, Canals M, Bunnett NW, Reed DE, Lomax AE, Vanner SJ. Opioid-Induced Pronociceptive Signaling in the Gastrointestinal Tract Is Mediated by Delta-Opioid Receptor Signaling. J Neurosci 2022; 42:3316-3328. [PMID: 35256532 PMCID: PMC9034783 DOI: 10.1523/jneurosci.2098-21.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 02/22/2022] [Accepted: 02/23/2022] [Indexed: 11/21/2022] Open
Abstract
Opioid tolerance (OT) leads to dose escalation and serious side effects, including opioid-induced hyperalgesia (OIH). We sought to better understand the mechanisms underlying this event in the gastrointestinal tract. Chronic in vivo administration of morphine by intraperitoneal injection in male C57BL/6 mice evoked tolerance and evidence of OIH in an assay of colonic afferent nerve mechanosensitivity; this was inhibited by the δ-opioid receptor (DOPr) antagonist naltrindole when intraperitoneally injected in previous morphine administration. Patch-clamp studies of DRG neurons following overnight incubation with high concentrations of morphine, the µ-opioid receptors (MOPr) agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-Enkephalin (DAMGO) or the DOPr agonist [D-Ala2, D-Leu5]-Enkephalin evoked hyperexcitability. The pronociceptive actions of these opioids were blocked by the DOPr antagonist SDM25N but not the MOPr antagonist D-Pen-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 The hyperexcitability induced by DAMGO was reversed after a 1 h washout, but reapplication of low concentrations of DAMGO or [D-Ala2, D-Leu5]-Enkephalin restored the hyperexcitability, an effect mediated by protein kinase C. DOPr-dependent DRG neuron hyperexcitability was blocked by the endocytosis inhibitor Pitstop 2, and the weakly internalizing DOPr agonist ARM390 did not cause hyperexcitability. Bioluminescence resonance energy transfer studies in HEK cells showed no evidence of switching of G-protein signaling from Gi to a Gs pathway in response to either high concentrations or overnight incubation of opioids. Thus, chronic high-dose opioid exposure leads to opioid tolerance and features of OIH in the colon. This action is mediated by DOPr signaling and is dependent on receptor endocytosis and downstream protein kinase C signaling.SIGNIFICANCE STATEMENT Opioids are effective in the treatment of abdominal pain, but escalating doses can lead to opioid tolerance and potentially opioid-induced hyperalgesia. We found that δ-opioid receptor (DOPr) plays a central role in the development of opioid tolerance and opioid-induced hyperalgesia in colonic afferent nociceptors following prolonged exposure to high concentrations of MOPr or DOPr agonists. Furthermore, the role of DOPr was dependent on OPr internalization and activation of a protein kinase C signaling pathway. Thus, targeting DOPr or key components of the downstream signaling pathway could mitigate adverse side effects by opioids.
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Affiliation(s)
- Josue Jaramillo-Polanco
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
| | - Cintya Lopez-Lopez
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
| | - Yang Yu
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
| | - Emma Neary
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
| | - Alan Hegron
- Department of Molecular Pathobiology, Department of Neuroscience and Physiology, Neuroscience Institute, New York University, New York, New York 10010
| | - Meritxell Canals
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, United Kingdom
- Centre of Membrane Protein and Receptors, Universities of Birmingham and Nottingham, Nottingham, NG7 2UH, United Kingdom
| | - Nigel W Bunnett
- Department of Molecular Pathobiology, Department of Neuroscience and Physiology, Neuroscience Institute, New York University, New York, New York 10010
| | - David E Reed
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
| | - Alan E Lomax
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
| | - Stephen J Vanner
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 2V7, Canada
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Aljassem A, Hall LM, Spickler M, Menkes DL. A Practical Approach to the Treatment of Painful Polyneuropathies. Neuromuscul Disord 2022. [DOI: 10.1016/b978-0-323-71317-7.00006-8] [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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5
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De Neve J, Barlow TMA, Tourwé D, Bihel F, Simonin F, Ballet S. Comprehensive overview of biased pharmacology at the opioid receptors: biased ligands and bias factors. RSC Med Chem 2021; 12:828-870. [PMID: 34223156 PMCID: PMC8221262 DOI: 10.1039/d1md00041a] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 03/30/2021] [Indexed: 12/19/2022] Open
Abstract
One of the main challenges in contemporary medicinal chemistry is the development of safer analgesics, used in the treatment of pain. Currently, moderate to severe pain is still treated with the "gold standard" opioids whose long-term often leads to severe side effects. With the discovery of biased agonism, the importance of this area of pharmacology has grown exponentially over the past decade. Of these side effects, tolerance, opioid misuse, physical dependence and substance use disorder (SUD) stand out, since these have led to many deaths over the past decades in both USA and Europe. New therapeutic molecules that induce a biased response at the opioid receptors (MOR, DOR, KOR and NOP receptor) are able to circumvent these side effects and, consequently, serve as more advantageous therapies with great promise. The concept of biased signaling extends far beyond the already sizeable field of GPCR pharmacology and covering everything would be vastly outside the scope of this review which consequently covers the biased ligands acting at the opioid family of receptors. The limitation of quantifying bias, however, makes this a controversial subject, where it is dependent on the reference ligand, the equation or the assay used for the quantification. Hence, the major issue in the field of biased ligands remains the translation of the in vitro profiles of biased signaling, with corresponding bias factors to in vivo profiles showing the presence or the lack of specific side effects. This review comprises a comprehensive overview of biased ligands in addition to their bias factors at individual members of the opioid family of receptors, as well as bifunctional ligands.
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Affiliation(s)
- Jolien De Neve
- Research Group of Organic Chemistry, Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel Brussels Belgium
| | - Thomas M A Barlow
- Research Group of Organic Chemistry, Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel Brussels Belgium
| | - Dirk Tourwé
- Research Group of Organic Chemistry, Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel Brussels Belgium
| | - Frédéric Bihel
- Laboratoire d'Innovation Thérapeutique, Faculté de Pharmacie, UMR 7200, CNRS Université de Strasbourg Illkirch France
| | - Frédéric Simonin
- Biotechnologie et Signalisation Cellulaire, UMR 7242, CNRS, Université de Strasbourg Illkirch France
| | - Steven Ballet
- Research Group of Organic Chemistry, Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel Brussels Belgium
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Pineyro G, Nagi K. Signaling diversity of mu- and delta- opioid receptor ligands: Re-evaluating the benefits of β-arrestin/G protein signaling bias. Cell Signal 2020; 80:109906. [PMID: 33383156 DOI: 10.1016/j.cellsig.2020.109906] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/24/2020] [Accepted: 12/27/2020] [Indexed: 01/02/2023]
Abstract
Opioid analgesics are elective for treating moderate to severe pain but their use is restricted by severe side effects. Signaling bias has been proposed as a viable means for improving this situation. To exploit this opportunity, continuous efforts are devoted to understand how ligand-specific modulations of receptor functions could mediate the different in vivo effects of opioids. Advances in the field have led to the development of biased agonists based on hypotheses that allocated desired and undesired effects to specific signaling pathways. However, the prevalent hypothesis associating β-arrestin to opioid side effects was recently challenged and multiple of the newly developed biased drugs may not display the superior side effects profile that was sought. Moreover, biased agonism at opioid receptors is now known to be time- and cell-dependent, which adds a new layer of complexity for bias estimation. Here, we first review the signaling mechanisms underlying desired and undesired effects of opioids. We then describe biased agonism at opioid receptors and discuss the different perspectives that support the desired and undesired effects of opioids in view of exploiting biased signaling for therapeutic purposes. Finally, we explore how signaling kinetics and cellular background can influence the magnitude and directionality of bias at those receptors.
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Affiliation(s)
- Graciela Pineyro
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada; CHU Sainte-Justine research center, Montreal, QC H3T 1C5, Canada
| | - Karim Nagi
- College of Medicine, QU Health, Qatar University, Doha, Qatar.
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7
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Bolin BL, Alcorn JL, Reynolds AR, Lile JA, Stoops WW, Rush CR. Human Drug Discrimination: Elucidating the Neuropharmacology of Commonly Abused Illicit Drugs. Curr Top Behav Neurosci 2019; 39:261-295. [PMID: 27272070 PMCID: PMC5461212 DOI: 10.1007/7854_2016_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Drug-discrimination procedures empirically evaluate the control that internal drug states have over behavior. They provide a highly selective method to investigate the neuropharmacological underpinnings of the interoceptive effects of drugs in vivo. As a result, drug discrimination has been one of the most widely used assays in the field of behavioral pharmacology. Drug-discrimination procedures have been adapted for use with humans and are conceptually similar to preclinical drug-discrimination techniques in that a behavior is differentially reinforced contingent on the presence or absence of a specific interoceptive drug stimulus. This chapter provides a basic overview of human drug-discrimination procedures and reviews the extant literature concerning the use of these procedures to elucidate the underlying neuropharmacological mechanisms of commonly abused illicit drugs (i.e., stimulants, opioids, and cannabis) in humans. This chapter is not intended to review every available study that used drug-discrimination procedures in humans. Instead, when possible, exemplary studies that used a stimulant, opioid, or Δ9-tetrahydrocannabinol (the primary psychoactive constituent of cannabis) to assess the discriminative-stimulus effects of drugs in humans are reviewed for illustrative purposes. We conclude by commenting on the current state and future of human drug-discrimination research.
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Affiliation(s)
- B Levi Bolin
- Department of Behavioral Science, University of Kentucky College of Medicine, 140 Medical Behavioral Science Building, Lexington, KY, 40536-0086, USA
| | - Joseph L Alcorn
- Department of Behavioral Science, University of Kentucky College of Medicine, 140 Medical Behavioral Science Building, Lexington, KY, 40536-0086, USA
| | - Anna R Reynolds
- Department of Behavioral Science, University of Kentucky College of Medicine, 140 Medical Behavioral Science Building, Lexington, KY, 40536-0086, USA
| | - Joshua A Lile
- Department of Behavioral Science, University of Kentucky College of Medicine, 140 Medical Behavioral Science Building, Lexington, KY, 40536-0086, USA
- Department of Psychology, University of Kentucky College of Arts and Sciences, 110 Kastle Hall, Lexington, KY, 40506-0044, USA
- Department of Psychiatry, University of Kentucky College of Medicine, 3470 Blazer Parkway, Lexington, KY, 40509, USA
| | - William W Stoops
- Department of Behavioral Science, University of Kentucky College of Medicine, 140 Medical Behavioral Science Building, Lexington, KY, 40536-0086, USA
- Department of Psychology, University of Kentucky College of Arts and Sciences, 110 Kastle Hall, Lexington, KY, 40506-0044, USA
- Department of Psychiatry, University of Kentucky College of Medicine, 3470 Blazer Parkway, Lexington, KY, 40509, USA
| | - Craig R Rush
- Department of Behavioral Science, University of Kentucky College of Medicine, 140 Medical Behavioral Science Building, Lexington, KY, 40536-0086, USA.
- Department of Psychology, University of Kentucky College of Arts and Sciences, 110 Kastle Hall, Lexington, KY, 40506-0044, USA.
- Department of Psychiatry, University of Kentucky College of Medicine, 3470 Blazer Parkway, Lexington, KY, 40509, USA.
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8
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Chedid V, Vijayvargiya P, Camilleri M. Advantages and Limitations of the Federal Adverse Events Reporting System in Assessing Adverse Event Reporting for Eluxadoline. Clin Gastroenterol Hepatol 2018; 16:336-338. [PMID: 29155353 PMCID: PMC5816691 DOI: 10.1016/j.cgh.2017.11.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/08/2017] [Accepted: 11/11/2017] [Indexed: 02/07/2023]
Affiliation(s)
- Victor Chedid
- Clinical Enteric Neuroscience Translational and Epidemiological Research, Mayo Clinic, Rochester, Minnesota
| | - Priya Vijayvargiya
- Clinical Enteric Neuroscience Translational and Epidemiological Research, Mayo Clinic, Rochester, Minnesota
| | - Michael Camilleri
- Clinical Enteric Neuroscience Translational and Epidemiological Research, Mayo Clinic, Rochester, Minnesota
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Lynch JJ, Van Vleet TR, Mittelstadt SW, Blomme EAG. Potential functional and pathological side effects related to off-target pharmacological activity. J Pharmacol Toxicol Methods 2017; 87:108-126. [PMID: 28216264 DOI: 10.1016/j.vascn.2017.02.020] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/24/2017] [Accepted: 02/15/2017] [Indexed: 12/22/2022]
Abstract
Most pharmaceutical companies test their discovery-stage proprietary molecules in a battery of in vitro pharmacology assays to try to determine off-target interactions. During all phases of drug discovery and development, various questions arise regarding potential side effects associated with such off-target pharmacological activity. Here we present a scientific literature curation effort undertaken to determine and summarize the most likely functional and pathological outcomes associated with interactions at 70 receptors, enzymes, ion channels and transporters with established links to adverse effects. To that end, the scientific literature was reviewed using an on-line database, and the most commonly reported effects were summarized in tabular format. The resultant table should serve as a practical guide for research scientists and clinical investigators for the prediction and interpretation of adverse side effects associated with molecules interacting with components of this screening battery.
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Affiliation(s)
- James J Lynch
- AbbVie Inc., 1 North Waukegan Road, North Chicago, IL 60064, USA.
| | | | | | - Eric A G Blomme
- AbbVie Inc., 1 North Waukegan Road, North Chicago, IL 60064, USA
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10
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Tsang SW, Auyeung KKW, Bian ZX, Ko JKS. Pathogenesis, Experimental Models and Contemporary Pharmacotherapy of Irritable Bowel Syndrome: Story About the Brain-Gut Axis. Curr Neuropharmacol 2017; 14:842-856. [PMID: 27009115 PMCID: PMC5333584 DOI: 10.2174/1570159x14666160324144154] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 02/07/2016] [Accepted: 03/22/2016] [Indexed: 11/22/2022] Open
Abstract
Background Although the precise pathophysiology of irritable bowel syndrome (IBS) remains unknown, it is generally considered to be a disorder of the brain-gut axis, representing the disruption of communication between the brain and the digestive system. The present review describes advances in understanding the pathophysiology and experimental approaches in studying IBS, as well as providing an update of the therapies targeting brain-gut axis in the treatment of the disease. Methods Causal factors of IBS are reviewed. Following this, the preclinical experimental models of IBS will be introduced. Besides, both current and future therapeutic approaches of IBS will be discussed. Results When signal of the brain-gut axis becomes misinterpreted, it may lead to dysregulation of both central and enteric nervous systems, altered intestinal motility, increased visceral sensitivity and consequently contributing to the development of IBS. Interference of the brain-gut axis can be modulated by various psychological and environmental factors. Although there is no existing animal experiment that can represent this complex multifactorial disease, these in vivo models are clinically relevant readouts of gastrointestinal functions being essential to the identification of effective treatments of IBS symptoms as well as their molecular targets. Understanding the brain-gut axis is essential in developing the effective therapy for IBS. Therapies include improvement of GI motor functions, relief of visceral hypersensitivity and pain, attenuation of autonomic dysfunctions and suppression of mucosal immune activation. Conclusion Target-oriented therapies that provide symptomatic, psychological and physiological benefits could surely help to improve the quality of life of IBS patients.
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Affiliation(s)
| | | | | | - J K S Ko
- Center for Cancer and Inflammation Research, School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Hong Kong SAR, China
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11
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Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2016; 68:631-700. [PMID: 27343248 PMCID: PMC4931872 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [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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12
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Sobolewska-Włodarczyk A, Włodarczyk M, Storr M, Fichna J. Clinical potential of eluxadoline in the treatment of diarrhea-predominant irritable bowel syndrome. Ther Clin Risk Manag 2016; 12:771-5. [PMID: 27257381 PMCID: PMC4874728 DOI: 10.2147/tcrm.s83722] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diarrhea-predominant irritable bowel syndrome (IBS-D) belongs to the group of functional gastrointestinal disorders and is characterized by abdominal pain in conjunction with diarrhea. The incidence of IBS-D is currently increasing, leading to a heavy economic burden for patients and health care systems worldwide. Recent studies suggest eluxadoline as an attractive new tool for the treatment of patients with IBS-D. Eluxadoline is an orally active μ- and κ-opioid receptor agonist and δ-opioid receptor antagonist, with powerful antidiarrheal and analgesic activity. Eluxadoline is believed to act locally in the enteric nervous system, and has no adverse effects in the central nervous system. In this review, we discuss the most recent findings on the mechanism of action of eluxadoline and the results of the clinical trials in patients with IBS-D. We also discuss possible side effects and analyze the potential of eluxadoline to be used in the treatment of IBS-D.
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Affiliation(s)
| | - Marcin Włodarczyk
- Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | | | - Jakub Fichna
- Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
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13
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Cyclic endomorphin analogs in targeting opioid receptors to achieve pain relief. Future Med Chem 2015; 6:2093-101. [PMID: 25531970 DOI: 10.4155/fmc.14.132] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Endomorphins, the endogenous ligands of the µ-opioid receptor, are attractive candidates for opioid-based pain-relieving agents. These tetrapeptides, with their remarkable affinity for the µ-opioid receptor, display favorable antinociceptive activity when injected directly into the brain of experimental animals. However, the application of endomorphins as clinical analgesics has been impeded by their instability in body fluids and inability to reach the brain after systemic administration. Among numerous modifications of the endomorphin structure aimed at improving their pharmacological properties, cyclization can be viewed as an interesting option. Here, we have summarized recent advances in obtaining endomorphin-based cyclic peptide analogs.
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14
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Kenakin T. Gaddum Memorial Lecture 2014: receptors as an evolving concept: from switches to biased microprocessors. Br J Pharmacol 2015; 172:4238-53. [PMID: 26075971 PMCID: PMC4556465 DOI: 10.1111/bph.13217] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/06/2015] [Accepted: 03/16/2015] [Indexed: 12/17/2022] Open
Abstract
This review is based on the JR Vane Medal Lecture presented at the BPS Winter Meeting in December 2014 by T. Kenakin. A recording of the lecture is included as supporting information and can also be viewed online here: https://www.youtube.com/watch?v=xrP81AQ8l-8. Pharmacological models used to describe drug agonism and antagonism have evolved over the past 20 years from a parsimonious model describing single active and inactive receptor states to models of multiconformational receptor systems modified by ligand conformational selection. These latter models describe the observed, presently underexploited, pharmacological mechanism of ligand-directed biased signalling. Biased signals can be quantified with transduction coefficients (ΔΔLog(τ/KA) values), a scale grounded in the Black/Leff operational model; this enables the optimization of biased profiles through medicinal chemistry. The past decades have also brought the availability of new technologies to measure multiple functional effects mediated by seven transmembrane receptors. These have confirmed that drugs can have many efficacies, which may be collaterally linked, that is there is no linear sequence of activities required. In addition, new functional screening assays have introduced increasing numbers of allosteric ligands into drug discovery. These molecules are permissive (they do not necessarily preclude endogenous signalling in vivo); therefore, they may allow better fine tuning of pathological physiology. The permissive quality of allosteric ligands can also change the quality of endogenous signalling efficacy ('induced bias') as well as the quantity of signal; in this regard, indices related to ΔΔLog(τ/KA) values (namely ΔLog(αβ) values) can be used to quantify these effects for optimization in the drug discovery process. All of these added scales of drug activity will, hopefully, allow better targeting of candidate molecules towards therapies.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of MedicineChapel Hill, NC, USA
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15
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Hallberg M. Neuropeptides: metabolism to bioactive fragments and the pharmacology of their receptors. Med Res Rev 2015; 35:464-519. [PMID: 24894913 DOI: 10.1002/med.21323] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
The proteolytic processing of neuropeptides has an important regulatory function and the peptide fragments resulting from the enzymatic degradation often exert essential physiological roles. The proteolytic processing generates, not only biologically inactive fragments, but also bioactive fragments that modulate or even counteract the response of their parent peptides. Frequently, these peptide fragments interact with receptors that are not recognized by the parent peptides. This review discusses tachykinins, opioid peptides, angiotensins, bradykinins, and neuropeptide Y that are present in the central nervous system and their processing to bioactive degradation products. These well-known neuropeptide systems have been selected since they provide illustrative examples that proteolytic degradation of parent peptides can lead to bioactive metabolites with different biological activities as compared to their parent peptides. For example, substance P, dynorphin A, angiotensin I and II, bradykinin, and neuropeptide Y are all degraded to bioactive fragments with pharmacological profiles that differ considerably from those of the parent peptides. The review discusses a selection of the large number of drug-like molecules that act as agonists or antagonists at receptors of neuropeptides. It focuses in particular on the efforts to identify selective drug-like agonists and antagonists mimicking the effects of the endogenous peptide fragments formed. As exemplified in this review, many common neuropeptides are degraded to a variety of smaller fragments but many of the fragments generated have not yet been examined in detail with regard to their potential biological activities. Since these bioactive fragments contain a small number of amino acid residues, they provide an ideal starting point for the development of drug-like substances with ability to mimic the effects of the degradation products. Thus, these substances could provide a rich source of new pharmaceuticals. However, as discussed herein relatively few examples have so far been disclosed of successful attempts to create bioavailable, drug-like agonists or antagonists, starting from the structure of endogenous peptide fragments and applying procedures relying on stepwise manipulations and simplifications of the peptide structures.
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Affiliation(s)
- Mathias Hallberg
- Beijer Laboratory, Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Uppsala University, Biomedical Center, Uppsala, Sweden
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16
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Gromova OA, Troshin IY, Limanova OA, Gromov AN, Fedotova LE, Rudakov KV. Neurotropic, anti-inflammatory and antitumor properties of hopantenic acid: a chemoinformatic analysis of its molecule. Zh Nevrol Psikhiatr Im S S Korsakova 2015; 115:61-71. [DOI: 10.17116/jnevro20151155261-71] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Lamberts JT, Traynor JR. Opioid receptor interacting proteins and the control of opioid signaling. Curr Pharm Des 2014; 19:7333-47. [PMID: 23448476 DOI: 10.2174/138161281942140105160625] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 02/18/2013] [Indexed: 12/31/2022]
Abstract
Opioid receptors are seven-transmembrane domain receptors that couple to intracellular signaling molecules by activating heterotrimeric G proteins. However, the receptor and G protein do not function in isolation but their activities are modulated by several accessory and scaffolding proteins. Examples include arrestins, kinases, and regulators of G protein signaling proteins. Accessory proteins contribute to the observed potency and efficacy of agonists, but also to the direction of signaling and the phenomenon of biased agonism. This review will present current knowledge of such proteins and how they may provide targets for future drug design.
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Affiliation(s)
| | - John R Traynor
- Department of Pharmacology, University of Michigan Medical School, 1301 MSRB III, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5632, USA.
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18
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Pain, agitation, delirium, and neuromuscular blockade: a review of basic pharmacology, assessment, and monitoring. Crit Care Nurs Q 2014; 36:356-69. [PMID: 24002426 DOI: 10.1097/cnq.0b013e3182a10dbf] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Agitation, pain, and delirium are focal points for targeted pharmacologic therapy in the intensive care unit. Understanding how to treat these essential entities necessitates fundamental understanding of the pharmacology of sedation, analgesia, and antipsychotics. Monitoring the effectiveness of these medications is crucial to optimize therapeutic outcomes and minimize untoward effects. Agents used in the management of agitation include drugs that target γ-aminobutyric acid A such as benzodiazepines and propofol and those with other targets such as dexmedetomidine and ketamine. Analgesia in the intensive care unit is controlled primarily using intravenous opioids, which differ on the basis of their potencies and pharmacokinetics. The management of delirium involves preventing its occurrence, removing potential causes, and pharmacotherapy with antipsychotics. Finally, the introduction of paralysis with the use neuromuscular blockers is often necessary in critically ill patients in various situations. In addition to understanding pharmacologic principles associated with the treatment of agitation, pain, and delirium, familiarization with the plethora of assessment tools used to guide therapy in these critically ill patients is mandated. This review focuses on the pharmacology of therapeutic agents used for sedation, analgesia, delirium, and neuromuscular blockade. Significant focus is given to the various assessment tools often used in practice today.
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Charfi I, Audet N, Bagheri Tudashki H, Pineyro G. Identifying ligand-specific signalling within biased responses: focus on δ opioid receptor ligands. Br J Pharmacol 2014; 172:435-48. [PMID: 24665881 DOI: 10.1111/bph.12705] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 03/17/2014] [Accepted: 03/20/2014] [Indexed: 01/13/2023] Open
Abstract
UNLABELLED Opioids activate GPCRs to produce powerful analgesic actions but at the same time induce side effects and generate tolerance, which restrict their clinical use. Reducing this undesired response profile has remained a major goal of opioid research and the notion of 'biased agonism' is raising increasing interest as a means of separating therapeutic responses from unwanted side effects. However, to fully exploit this opportunity, it is necessary to confidently identify biased signals and evaluate which type of bias may support analgesia and which may lead to undesired effects. The development of new computational tools has made it possible to quantify ligand-dependent signalling and discriminate this component from confounders that may also yield biased responses. Here, we analyse different approaches to identify and quantify ligand-dependent bias and review different types of confounders. Focus is on δ opioid receptor ligands, which are currently viewed as promising agents for chronic pain management. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- I Charfi
- Sainte-Justine Hospital Research Center, Montreal, QC, Canada; Department of Pharmacology, Faculty of Medicine, University of Montreal, Montreal, QC, Canada
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20
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Kenakin T. New concepts in pharmacological efficacy at 7TM receptors: IUPHAR review 2. Br J Pharmacol 2013; 168:554-75. [PMID: 22994528 PMCID: PMC3579279 DOI: 10.1111/j.1476-5381.2012.02223.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 08/03/2012] [Accepted: 09/12/2012] [Indexed: 01/14/2023] Open
Abstract
The present-day concept of drug efficacy has changed completely from its original description as the property of agonists that causes tissue activation. The ability to visualize the multiple behaviours of seven transmembrane receptors has shown that drugs can have many efficacies and also that the transduction of drug stimulus to various cellular stimulus-response cascades can be biased towards some but not all pathways. This latter effect leads to agonist 'functional selectivity', which can be favourable for the improvement of agonist therapeutics. However, in addition, biased agonist potency becomes cell type dependent with the loss of the monotonic behaviour of stimulus-response mechanisms, leading to potential problems in agonist quantification. This has an extremely important effect on the discovery process for new agonists since it now cannot be assumed that a given screening or lead optimization assay will correctly predict therapeutic behaviour. This review discusses these ideas and how new approaches to quantifying agonist effect may be used to circumvent the cell type dependence of agonism. This article, written by a corresponding member of the International Union of Basic and Clinical Pharmacology Committee on Receptor Nomenclature and Drug Classification (NC-IUPHAR), reviews our current understanding of the interaction of ligands with seven transmembrane receptors. Further information on these pharmacological concepts is being incorporated into the IUPHAR/BPS database GuideToPharmacology.org.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
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21
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Subirán N, Candenas L, Pinto FM, Cejudo-Roman A, Agirregoitia E, Irazusta J. Autocrine regulation of human sperm motility by the met-enkephalin opioid peptide. Fertil Steril 2012; 98:617-625.e3. [DOI: 10.1016/j.fertnstert.2012.05.036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 05/23/2012] [Accepted: 05/23/2012] [Indexed: 01/29/2023]
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Abstract
Opioid receptors have been targeted for the treatment of pain and related disorders for thousands of years and remain the most widely used analgesics in the clinic. Mu (μ), kappa (κ), and delta (δ) opioid receptors represent the originally classified receptor subtypes, with opioid receptor like-1 (ORL1) being the least characterized. All four receptors are G-protein coupled and activate inhibitory G proteins. These receptors form homo- and heterodimeric complexes and signal to kinase cascades and scaffold a variety of proteins.The authors discuss classic mechanisms and developments in understanding opioid tolerance and opioid receptor signaling and highlight advances in opioid molecular pharmacology, behavioral pharmacology, and human genetics. The authors put into context how opioid receptor signaling leads to the modulation of behavior with the potential for therapeutic intervention. Finally, the authors conclude there is a continued need for more translational work on opioid receptors in vivo.
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23
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McCarthy MJ, Zhang H, Neff NH, Hadjiconstantinou M. Desensitization of δ-opioid receptors in nucleus accumbens during nicotine withdrawal. Psychopharmacology (Berl) 2011; 213:735-44. [PMID: 20941594 DOI: 10.1007/s00213-010-2028-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2010] [Accepted: 09/18/2010] [Indexed: 11/26/2022]
Abstract
RATIONALE The synthesis and release of met-enkephalin and β-endorphin, endogenous ligands for δ-opioid peptide receptors (DOPrs), are altered following nicotine administration and may play a role in nicotine addiction. OBJECTIVES To investigate the consequences of altered opioidergic activity on DOPr expression, coupling, and function in striatum during early nicotine withdrawal. METHODS Mice received nicotine-free base, 2 mg/kg, or saline, subcutaneously (s.c.), four times daily for 14 days and experiments performed at 24, 48, and 72 h after drug discontinuation. DOPr binding and mRNA were evaluated by [³H]naltrindole autoradiography and in situ hybridization. DOPr coupling and function were investigated by agonist pCl-DPDPE-stimulated [³⁵S]GTPγS binding autoradiography and inhibition of adenylyl cyclase activity. RESULTS During nicotine withdrawal DOPr binding was unaltered in caudate/putamen (CPu) and nucleus accumbens (NAc) shell and core. Receptor mRNA was slightly increased in the shell at 72 h, but significant elevations were observed in prefrontal cortex and hippocampus. pCl-DPDPE-stimulated [³⁵S]GTPγS binding was attenuated in NAc, but not CPu. In the shell, binding was decreased by 48 h and remained decreased over 72 h; while in the core, significant reduction was seen at 72 h. Basal adenylyl cyclase activity was suppressed in striatum at 24 h, but recovered by 48 h. DOPr stimulation with pCl-DPDPE failed to inhibit adenylyl cyclase activity at 24 h and produced attenuated responses at 48 and 72 h. CONCLUSIONS These observations suggest that DOPr coupling and function are impaired in the NAc during nicotine withdrawal. DOPr desensitization might be involved in the affective component of nicotine withdrawal.
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Affiliation(s)
- Michael J McCarthy
- Department of Psychiatry, Division of Molecular Neuropsychopharmacology, The Ohio State University College of Medicine, Columbus, OH 43210, USA
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24
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Abstract
With the emergence of information describing functional selectivity and biased agonists and antagonists has come a lack of confidence in "one size fits all" assays for detection of agonism. Seven-transmembrane receptors are pleiotropic with respect to the signaling protein to which they couple in a cell, and many conformations of the receptor can be formed; this leads to systems where ligands can stabilize unique conformations that go on to selectively activate signaling pathways. Thus, such "biased" ligands can produce cell-specific agonism that may require targeted assays to detect and quantify. It also predicts that ligands can have many different efficacies for the many behaviors that the receptor can exhibit (referred to as "pluridimensional efficacy"), leading to a breakdown in the common classifications of agonist and antagonist. This all poses unique challenges to the pharmacologic nomenclature of drugs, the detection and optimization of new drugs, and the association of phenotypic clinical profiles with pharmacological properties of drugs.
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Affiliation(s)
- Terry Kenakin
- Platform Technology Sciences, GlaxoSmithKline Research and Development, Research Triangle Park, NC 27709, USA.
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25
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Kenakin T, Miller LJ. Seven transmembrane receptors as shapeshifting proteins: the impact of allosteric modulation and functional selectivity on new drug discovery. Pharmacol Rev 2010; 62:265-304. [PMID: 20392808 PMCID: PMC2879912 DOI: 10.1124/pr.108.000992] [Citation(s) in RCA: 469] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
It is useful to consider seven transmembrane receptors (7TMRs) as disordered proteins able to allosterically respond to a number of binding partners. Considering 7TMRs as allosteric systems, affinity and efficacy can be thought of in terms of energy flow between a modulator, conduit (the receptor protein), and a number of guests. These guests can be other molecules, receptors, membrane-bound proteins, or signaling proteins in the cytosol. These vectorial flows of energy can yield standard canonical guest allostery (allosteric modification of drug effect), effects along the plane of the cell membrane (receptor oligomerization), or effects directed into the cytosol (differential signaling as functional selectivity). This review discusses these apparently diverse pharmacological effects in terms of molecular dynamics and protein ensemble theory, which tends to unify 7TMR behavior toward cells. Special consideration will be given to functional selectivity (biased agonism and biased antagonism) in terms of mechanism of action and potential therapeutic application. The explosion of technology that has enabled observation of diverse 7TMR behavior has also shown how drugs can have multiple (pluridimensional) efficacies and how this can cause paradoxical drug classification and nomenclatures.
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Affiliation(s)
- Terry Kenakin
- GlaxoSmithKline, 5 Moore Drive, Mailtstop V-287, Research Triangle Park, NC 27709, USA.
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26
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Mabrouk O, Marti M, Salvadori S, Morari M. The novel delta opioid receptor agonist UFP-512 dually modulates motor activity in hemiparkinsonian rats via control of the nigro-thalamic pathway. Neuroscience 2009; 164:360-9. [DOI: 10.1016/j.neuroscience.2009.08.058] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 07/28/2009] [Accepted: 08/25/2009] [Indexed: 11/26/2022]
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Autoantibodies to the delta-opioid receptor function as opioid agonists and display immunomodulatory activity. J Neuroimmunol 2009; 217:65-73. [PMID: 19879656 DOI: 10.1016/j.jneuroim.2009.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 10/07/2009] [Accepted: 10/09/2009] [Indexed: 01/20/2023]
Abstract
In this report, we show that affinity purified human anti-delta opioid receptor (DOR) autoantibodies from IVIG are specific to DOR and possess agonistic properties displayed by their ability to dramatically decrease forskolin stimulated cAMP accumulation. Anti-DOR autoantibody also caused phosphorylation of the opioid receptor. Anti-DOR autoantibody treatment showed a significant reduction in CXCR4 gene expression as well as surface protein expression. In contrast, anti-DOR autoantibody treatment significantly upregulated CCR5 gene and protein expression. The presence of anti-DOR autoantibodies in IVIG and their potent immunomodulatory activity is further evidence to support the cross-talk between the neuroendocrine and immune systems.
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Beaudry H, Proteau-Gagné A, Li S, Dory Y, Chavkin C, Gendron L. Differential noxious and motor tolerance of chronic delta opioid receptor agonists in rodents. Neuroscience 2009; 161:381-91. [PMID: 19328839 PMCID: PMC3727641 DOI: 10.1016/j.neuroscience.2009.03.053] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 03/19/2009] [Accepted: 03/20/2009] [Indexed: 01/28/2023]
Abstract
In the present study, we asked whether multiple intrathecal injections of deltorphin II, a selective delta opioid receptor (DOPR) agonist, induced DOPR tolerance in three behavioral assays. Unilateral inflammation caused by complete Freund's adjuvant (CFA) injection into the rat or mouse hind paw (CFA model) induced thermal hyperalgesic response that was transiently and dose-dependently reduced by intrathecal administration of deltorphin II or morphine. In both rodent species, the effect of deltorphin II was not modified by a single prior administration of deltorphin II, suggesting an absence of acute tolerance in this paradigm. Repeated administration of intrathecal deltorphin II or s.c. SB-235863 (five consecutive injections over 60 h) also failed to impair the antihyperalgesic response to delta opioid receptor agonist, whereas repeated intrathecal or s.c. injections of morphine induced a significant decrease in the subsequent thermal antihyperalgesic response to morphine. In mice, deltorphin II also induced a rapid, transient motor incoordination/ataxia-like behavior as tested with the accelerating rotarod. In contrast to the antihyperalgesic responses, tolerance to the motoric effect of deltorphin II was evident in mice previously exposed to multiple intrathecal agonist injections, but not multiple saline administrations. Using the tail flick antinociceptive test, we found that DOPR-mediated analgesia was significantly reduced by repeated exposure to deltorphin II. Altogether, these observations suggest that repeated injections of DOPR agonists induce differential tolerance effects on antihyperalgesic, antinociceptive, and motor incoordination/ataxia-like behaviors related to DOPR activation by deltorphin II.
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Affiliation(s)
- H. Beaudry
- Department of Physiology and Biophysics, Université de Sherbrooke, Faculty of Medicine, 3001, 12e Avenue Nord, Sherbrooke, QC, Canada
| | - A. Proteau-Gagné
- Department of Chemistry, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Shuang Li
- Department of Pharmacology, University of Washington, Seattle, WA 98195–7280, USA
| | - Y. Dory
- Department of Chemistry, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - C. Chavkin
- Department of Pharmacology, University of Washington, Seattle, WA 98195–7280, USA
| | - L. Gendron
- Department of Physiology and Biophysics, Université de Sherbrooke, Faculty of Medicine, 3001, 12e Avenue Nord, Sherbrooke, QC, Canada
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Huang P, Xu W, Yoon SI, Chen C, Chong PLG, Liu-Chen LY. Cholesterol reduction by methyl-beta-cyclodextrin attenuates the delta opioid receptor-mediated signaling in neuronal cells but enhances it in non-neuronal cells. Biochem Pharmacol 2007; 73:534-49. [PMID: 17141202 PMCID: PMC2583444 DOI: 10.1016/j.bcp.2006.10.032] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2006] [Revised: 10/30/2006] [Accepted: 10/31/2006] [Indexed: 11/30/2022]
Abstract
Opioid receptors have been shown to be located in and regulated by lipid rafts/caveolae in caveolin-rich non-neuronal cells. Here, we found that caveolin-1 level was very low in rat brain and undetectable in NG108-15 cells, which endogenously express delta opioid receptors (DOR). Rat caudate putamen (CPu) membranes, NG108-15 cells and CHO cells stably transfected with FLAG-mouse-DOR (CHO-FLAG-mDOR) were homogenized, sonicated in a detergent-free 0.5M Na(2)CO(3) buffer and fractionated through discontinuous or continuous sucrose density gradients. About 70% of opioid receptors in CPu and DOR in both cell lines were present in low-density (5-20% sucrose) membrane domains enriched in cholesterol and ganglioside M1 (GM1), characteristics of lipid rafts in plasma membranes. In both cells, stimulation with permeable or non-permeable full agonists, but not with partial or inverse agonists, for 30min shifted approximately 25% of DORs out of rafts, by a naloxone-reversible and pertussis toxin-insensitive mechanism, which may undergo internalization. Methyl-beta-cyclodextrin (MCD) treatment greatly reduced cholesterol and shifted DOR to higher density fractions and decreased DPDPE affinities. MCD treatment attenuated DPDPE-induced [(35)S]GTPgammaS binding in CPu and NG108-15 cells, but enhanced it in CHO-FLAG-mDOR cells. In CHO-FLAG-mDOR cells, G(alphai) co-immunoprecipitated with caveolin-1, which was shown to inhibit G(alphai/o), and MCD treatment dramatically reduced the association leading to disinhibition. Thus, although localization in rafts and agonist-induced shift of DOR are independent of caveolin-1, lipid rafts sustain DOR-mediated signaling in caveolin-deficient neuronal cells, but appear to inhibit it in caveolin-enriched non-neuronal cells. Cholesterol-dependent association of caveolin-1 with and the resulting inhibition of G proteins may be a contributing factor.
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Affiliation(s)
- Peng Huang
- Department of Pharmacology, Center for Substance Abuse Research, Temple University School of Medicine, 3420 N Broad Street, Philadelphia, PA 19140, United States
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30
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Balboni G, Onnis V, Congiu C, Zotti M, Sasaki Y, Ambo A, Bryant SD, Jinsmaa Y, Lazarus LH, Trapella C, Salvadori S. Effect of lysine at C-terminus of the Dmt-Tic opioid pharmacophore. J Med Chem 2006; 49:5610-7. [PMID: 16942034 PMCID: PMC2533050 DOI: 10.1021/jm060741w] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Substitution of Gly with side-chain-protected or unprotected Lys in lead compounds containing the opioid pharmacophore Dmt-Tic [H-Dmt-Tic-Gly-NH-CH(2)-Ph, mu agonist/delta antagonist; H-Dmt-Tic-Gly-NH-Ph, mu agonist/delta agonist; and H-Dmt-Tic-NH-CH(2)-Bid, delta agonist (Bid = 1H-benzimidazole-2-yl)] yielded a new series of compounds endowed with distinct pharmacological activities. Compounds (1-10) included high delta- (Ki(delta) = 0.068-0.64 nM) and mu-opioid affinities (Ki(mu) = 0.13-5.50 nM), with a bioactivity that ranged from mu-opioid agonism {10, H-Dmt-Tic-NH-CH[(CH2)4-NH2]-Bid (IC50 GPI = 39.7 nM)} to a selective mu-opioid antagonist [3, H-Dmt-Tic-Lys-NH-CH2-Ph (pA2(mu) = 7.96)] and a selective delta-opioid antagonist [5, H-Dmt-Tic-Lys(Ac)-NH-Ph (pA2(delta) = 12.0)]. The presence of a Lys linker provides new lead compounds in the formation of opioid peptidomimetics containing the Dmt-Tic pharmacophore with distinct agonist and/or antagonist properties.
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MESH Headings
- Animals
- Dipeptides/chemical synthesis
- Dipeptides/chemistry
- Dipeptides/pharmacology
- Electric Stimulation
- Guinea Pigs
- Ileum/drug effects
- Ileum/physiology
- In Vitro Techniques
- Ligands
- Male
- Mice
- Muscle, Smooth/drug effects
- Muscle, Smooth/physiology
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Structure-Activity Relationship
- Tetrahydroisoquinolines/chemical synthesis
- Tetrahydroisoquinolines/chemistry
- Tetrahydroisoquinolines/pharmacology
- Vas Deferens/drug effects
- Vas Deferens/physiology
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Affiliation(s)
- Gianfranco Balboni
- Department of Toxicology, University of Cagliari, I-09124, Cagliari, Italy.
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31
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Davis S, Deo SH, Barlow M, Yoshishige D, Farias M, Caffrey JL. The monosialosyl ganglioside GM-1 reduces the vagolytic efficacy of delta2-opioid receptor stimulation. Am J Physiol Heart Circ Physiol 2006; 291:H2318-26. [PMID: 16815987 DOI: 10.1152/ajpheart.00455.2006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The cardiac enkephalin, methionine-enkephalin-arginine-phenylalanine (MEAP), alters vagally induced bradycardia when introduced by microdialysis into the sinoatrial (SA) node. The responses to MEAP are bimodal; lower doses enhance bradycardia and higher doses suppress bradycardia. The opposing vagotonic and vagolytic effects are mediated, respectively, by delta(1) and delta(2) phenotypes of the same receptor. Stimulation of the delta(1) receptor reduced the subsequent delta(2) responses. Experiments were conducted to test the hypothesis that the delta-receptor interactions were mediated by the monosialosyl ganglioside GM-1. When the mixed agonist MEAP was evaluated after nodal GM-1 treatment, delta(1)-mediated vagotonic responses were enhanced, and delta(2)-mediated vagolytic responses were reduced. Prior treatment with the delta(1)-selective antagonist 7-benzylidenaltrexone (BNTX) failed to prevent attrition of the delta(2)-vagolytic response or restore it when added afterward. Thus the GM-1-mediated attrition was not mediated by delta(1) receptors or increased competition from delta(1)-mediated vagotonic responses. When GM-1 was omitted, deltorphin produced a similar but less robust loss in the vagolytic response. In contrast, however, to GM-1, the deltorphin-mediated attrition was prevented by pretreatment with BNTX, indicating that the decline in response after deltorphin alone was mediated by delta(1) receptors and that GM-1 effectively bypassed the receptor. Whether deltorphin has intrinsic delta(1) activity or causes the release of an endogenous delta(1)-agonist is unclear. When both GM-1 and deltorphin were omitted, the subsequent vagolytic response was more intense. Thus GM-1, deltorphin, and time all interact to modify subsequent delta(2)-mediated vagolytic responses. The data support the hypothesis that delta(1)-receptor stimulation may reduce delta(2)-vagolytic responses by stimulating the GM-1 synthesis.
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MESH Headings
- Analgesics, Opioid/pharmacology
- Animals
- Benzylidene Compounds/pharmacology
- Bradycardia/drug therapy
- Bradycardia/physiopathology
- Dogs
- Dose-Response Relationship, Drug
- Enkephalin, Methionine/analogs & derivatives
- Enkephalin, Methionine/pharmacology
- Female
- G(M1) Ganglioside/pharmacology
- Male
- Naltrexone/analogs & derivatives
- Naltrexone/pharmacology
- Narcotic Antagonists/pharmacology
- Oligopeptides/pharmacology
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/metabolism
- Sinoatrial Node/drug effects
- Sinoatrial Node/innervation
- Sinoatrial Node/physiology
- Stimulation, Chemical
- Vagus Nerve/drug effects
- Vagus Nerve/physiology
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Affiliation(s)
- Shavsha Davis
- Univ. of North Texas Health Science Center, Dept. of Integrative Physiology, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107. )
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Tourwé D, Salvadori S, Bryant SD, Jinsmaa Y, Lazarus LH, Negri L, Giannini E, Lattanzi R, Balboni G. New 2',6'-dimethyl-L-tyrosine (Dmt) opioid peptidomimetics based on the Aba-Gly scaffold. Development of unique mu-opioid receptor ligands. J Med Chem 2006; 49:3990-3. [PMID: 16789756 PMCID: PMC2983084 DOI: 10.1021/jm0603264] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Aba-Gly scaffold, incorporated into Dmt-Tic ligands (H-Dmt-Tic-Gly-NH-CH2-Ph, H-Dmt-Tic-Gly-NH-Ph, H-Dmt-Tic-NH-CH2-Bid), exhibited mixed micro/delta or delta opioid receptor activities with micro agonism. Substitution of Tic by Aba-Gly coupled to -NH-CH2-Ph (1), -NH-Ph (2), or -Bid (Bid=1H-benzimidazole-2-yl) (3) shifted affinity (Ki(micro)=0.46, 1.48, and 19.9 nM, respectively), selectivity, and bioactivity to micro-opioid receptors. These compounds represent templates for a new class of lead opioid agonists that are easily synthesized and suitable for therapeutic pain relief.
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MESH Headings
- Analgesics, Opioid/chemical synthesis
- Analgesics, Opioid/chemistry
- Analgesics, Opioid/pharmacology
- Animals
- Benzazepines/chemical synthesis
- Benzazepines/pharmacology
- Glycine/analogs & derivatives
- Glycine/chemical synthesis
- Glycine/pharmacology
- Guinea Pigs
- In Vitro Techniques
- Ligands
- Molecular Mimicry
- Muscle Contraction/drug effects
- Muscle, Smooth/drug effects
- Muscle, Smooth/innervation
- Muscle, Smooth/physiology
- Myenteric Plexus/physiology
- Peptides/chemistry
- Rats
- Rats, Sprague-Dawley
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, mu/agonists
- Structure-Activity Relationship
- Synaptosomes/drug effects
- Synaptosomes/metabolism
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Affiliation(s)
- Dirk Tourwé
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Severo Salvadori
- Department of Pharmaceutical Sciences and Biotechnology Center, University of Ferrara, I-44100 Ferrara, Italy
| | - Sharon D. Bryant
- Medicinal Chemistry Group, Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Yunden Jinsmaa
- Medicinal Chemistry Group, Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Lawrence H. Lazarus
- Medicinal Chemistry Group, Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Lucia Negri
- Department of Human Physiology and Pharmacology “Vittorio Erspamer,” University La Sapienza, I-00185 Rome, Italy
| | - Elisa Giannini
- Department of Human Physiology and Pharmacology “Vittorio Erspamer,” University La Sapienza, I-00185 Rome, Italy
| | - Roberta Lattanzi
- Department of Human Physiology and Pharmacology “Vittorio Erspamer,” University La Sapienza, I-00185 Rome, Italy
| | - Gianfranco Balboni
- Department of Pharmaceutical Sciences and Biotechnology Center, University of Ferrara, I-44100 Ferrara, Italy
- Department of Toxicology, University of Cagliari, I-09124, Cagliari, Italy
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Johnson EE, Christie MJ, Connor M. The Role of Opioid Receptor Phosphorylation and Trafficking in Adaptations to Persistent Opioid Treatment. Neurosignals 2006; 14:290-302. [PMID: 16772732 DOI: 10.1159/000093044] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Indexed: 11/19/2022] Open
Abstract
Mu-opioid receptor activation underpins clinical analgesia and is the central event in the abuse of narcotics. Continued opioid use produces tolerance to the acute effects of the drug and adaptations that lead to physical and psychological dependence. Continued mu-receptor signaling provides the engine for these adaptations, with most evidence suggesting that chronic agonist treatment produces only limited alterations in primary mu-opioid receptor signaling. Here we examine agonist regulation of mu-opioid receptor function, and whether this is altered by chronic treatment. Receptor phosphorylation is thought to be the key initial event in agonist regulation of the mu-opioid receptor, providing a signal for acute receptor desensitization and also subsequent receptor resensitization. Morphine appears to produce qualitatively and quantitatively different mu-receptor phosphorylation than other agonists, but the consequences of this remain obscure, at least in neurons. There is no evidence that agonist-induced mu-opioid receptor phosphorylation changes in chronically morphine-treated animals, although receptor regulation appears to be altered. Thus, as receptor phosphorylation and resensitization appear to maintain continued signaling through the mu-opioid receptor, these two events are crucial in facilitating adaptations to chronic opioid treatment, and the possibility that agonist-specific phosphorylation can contribute to the development of different adaptations remains open.
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Affiliation(s)
- Emma E Johnson
- Pain Management Research Institute, Kolling Institute, University of Sydney at Royal North Shore Hospital, St. Leonards, Australia
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34
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Millan MJ. Multi-target strategies for the improved treatment of depressive states: Conceptual foundations and neuronal substrates, drug discovery and therapeutic application. Pharmacol Ther 2006; 110:135-370. [PMID: 16522330 DOI: 10.1016/j.pharmthera.2005.11.006] [Citation(s) in RCA: 397] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Accepted: 11/28/2005] [Indexed: 12/20/2022]
Abstract
Major depression is a debilitating and recurrent disorder with a substantial lifetime risk and a high social cost. Depressed patients generally display co-morbid symptoms, and depression frequently accompanies other serious disorders. Currently available drugs display limited efficacy and a pronounced delay to onset of action, and all provoke distressing side effects. Cloning of the human genome has fuelled expectations that symptomatic treatment may soon become more rapid and effective, and that depressive states may ultimately be "prevented" or "cured". In pursuing these objectives, in particular for genome-derived, non-monoaminergic targets, "specificity" of drug actions is often emphasized. That is, priority is afforded to agents that interact exclusively with a single site hypothesized as critically involved in the pathogenesis and/or control of depression. Certain highly selective drugs may prove effective, and they remain indispensable in the experimental (and clinical) evaluation of the significance of novel mechanisms. However, by analogy to other multifactorial disorders, "multi-target" agents may be better adapted to the improved treatment of depressive states. Support for this contention is garnered from a broad palette of observations, ranging from mechanisms of action of adjunctive drug combinations and electroconvulsive therapy to "network theory" analysis of the etiology and management of depressive states. The review also outlines opportunities to be exploited, and challenges to be addressed, in the discovery and characterization of drugs recognizing multiple targets. Finally, a diversity of multi-target strategies is proposed for the more efficacious and rapid control of core and co-morbid symptoms of depression, together with improved tolerance relative to currently available agents.
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Affiliation(s)
- Mark J Millan
- Institut de Recherches Servier, Centre de Recherches de Croissy, Psychopharmacology Department, 125, Chemin de Ronde, 78290-Croissy/Seine, France.
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35
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Abstract
This paper is the 27th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over 30 years of research. It summarizes papers published during 2004 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, USA.
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36
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Bernard D, Coop A, MacKerell AD. Conformationally sampled pharmacophore for peptidic delta opioid ligands. J Med Chem 2005; 48:7773-80. [PMID: 16302816 DOI: 10.1021/jm050785p] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Opioids represent the frontline treatment for acute pain, despite their side effects, motivating efforts toward developing novel opioid analgesics. To facilitate these efforts, a novel modeling approach, the conformationally sampled pharmacophore (CSP), has been developed that increases the probability of including the receptor bound form in the model. This method, originally used for developing a nonpeptidic delta opioid efficacy pharmacophore, is extended to peptidic ligands using replica exchange molecular dynamics simulation for conformational sampling. The developed 2D CSP indicates that the spatial relationship of the basic nitrogen and the hydrophobic moiety in the delta opioid ligands differentiates activity. In addition, results indicate that both peptidic and nonpeptidic ligands have the same binding mode with the receptor. Thus, the CSP approach distinguishes both peptidic and nonpeptidic delta opioid agonists and antagonists and is anticipated to be of general utility for the development of pharmacophores for species with multiple rotatable bonds.
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Affiliation(s)
- Denzil Bernard
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201, USA
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