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Mogil JS, Parisien M, Esfahani SJ, Diatchenko L. Sex differences in mechanisms of pain hypersensitivity. Neurosci Biobehav Rev 2024; 163:105749. [PMID: 38838876 DOI: 10.1016/j.neubiorev.2024.105749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/23/2024] [Accepted: 06/02/2024] [Indexed: 06/07/2024]
Abstract
The introduction of sex-as-a-biological-variable policies at funding agencies around the world has led to an explosion of very recent observations of sex differences in the biology underlying pain. This review considers evidence of sexually dimorphic mechanisms mediating pain hypersensitivity, derived from modern assays of persistent pain in rodent animal models. Three well-studied findings are described in detail: the male-specific role of spinal cord microglia, the female-specific role of calcitonin gene-related peptide (CGRP), and the female-specific role of prolactin and its receptor. Other findings of sex-specific molecular involvement in pain are subjected to pathway analyses and reveal at least one novel hypothesis: that females may preferentially use Th1 and males Th2 T cell activity to mediate chronic pain.
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Affiliation(s)
- Jeffrey S Mogil
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC H3A 1B1, Canada.
| | - Marc Parisien
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC H3A 1B1, Canada
| | - Sahel J Esfahani
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC H3A 1B1, Canada
| | - Luda Diatchenko
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC H3A 1B1, Canada
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2
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Norris MR, Becker LJ, Bilbily J, Chang YH, Borges G, Dunn SS, Madasu MK, Vazquez CR, Cariello SA, Al-Hasani R, Creed MC, McCall JG. Spared nerve injury decreases motivation in long-access homecage-based operant tasks in mice. Pain 2024; 165:1247-1265. [PMID: 38015628 PMCID: PMC11095834 DOI: 10.1097/j.pain.0000000000003123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 10/10/2023] [Indexed: 11/30/2023]
Abstract
ABSTRACT Neuropathic pain causes both sensory and emotional maladaptation. Preclinical animal studies of neuropathic pain-induced negative affect could result in novel insights into the mechanisms of chronic pain. Modeling pain-induced negative affect, however, is variable across research groups and conditions. The same injury may or may not produce robust negative affective behavioral responses across different species, strains, and laboratories. Here, we sought to identify negative affective consequences of the spared nerve injury model on C57BL/6J male and female mice. We found no significant effect of spared nerve injury across a variety of approach-avoidance conflict, hedonic choice, and coping strategy assays. We hypothesized these inconsistencies may stem in part from the short test duration of these assays. To test this hypothesis, we used the homecage-based Feeding Experimentation Device version 3 to conduct 12-hour, overnight progressive ratio testing to determine whether mice with chronic spared nerve injury had decreased motivation to earn palatable food rewards. Our data demonstrate that despite equivalent task learning, spared nerve injury mice are less motivated to work for a sugar pellet than sham controls. Furthermore, when we normalized behavioral responses across all the behavioral assays we tested, we found that a combined normalized behavioral score is predictive of injury state and significantly correlates with mechanical thresholds. Together, these results suggest that homecage-based operant behaviors provide a useful platform for modeling nerve injury-induced negative affect and that valuable pain-related information can arise from agglomerative data analyses across behavioral assays-even when individual inferential statistics do not demonstrate significant mean differences.
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Affiliation(s)
- Makenzie R. Norris
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Léa J. Becker
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - John Bilbily
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO, USA
| | - Yu-Hsuan Chang
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Gustavo Borges
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Samantha S. Dunn
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Manish K. Madasu
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Chayla R. Vazquez
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Solana A. Cariello
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Ream Al-Hasani
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Meaghan C. Creed
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO, USA
| | - Jordan G. McCall
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
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3
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Dagher M, Alayoubi M, Sigal GH, Cahill CM. Unveiling the link between chronic pain and misuse of opioids and cannabis. J Neural Transm (Vienna) 2024; 131:563-580. [PMID: 38570361 DOI: 10.1007/s00702-024-02765-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/10/2024] [Indexed: 04/05/2024]
Abstract
Over 50 million Americans endure chronic pain where many do not receive adequate treatment and self-medicate to manage their pain by taking substances like opioids and cannabis. Research has shown high comorbidity between chronic pain and substance use disorders (SUD) and these disorders share many common neurobiological underpinnings, including hypodopaminergic transmission. Drugs commonly used for self-medication such as opioids and cannabis relieve emotional, bothersome components of pain as well as negative emotional affect that perpetuates misuse and increases the risk of progressing towards drug abuse. However, the causal effect between chronic pain and the development of SUDs has not been clearly established. In this review, we discuss evidence that affirms the proposition that chronic pain is a risk factor for the development of opioid and cannabis use disorders by outlining the clinical evidence and detailing neurobiological mechanisms that link pain and drug misuse. Central to the link between chronic pain and opioid and cannabis misuse is hypodopaminergic transmission and the modulation of dopamine signaling in the mesolimbic pathway by opioids and cannabis. Moreover, we discuss the role of kappa opioid receptor activation and neuroinflammation in the context of dopamine transmission, their contribution to opioid and cannabis withdrawal, along with potential new treatments.
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Affiliation(s)
- Merel Dagher
- MacDonald Research Laboratory Building, Department of Psychiatry and Biobehavioral Sciences, Shirley and Stefan Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E Young Drive South, Office 2774, Los Angeles, CA, 90095, USA
| | - Myra Alayoubi
- MacDonald Research Laboratory Building, Department of Psychiatry and Biobehavioral Sciences, Shirley and Stefan Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E Young Drive South, Office 2774, Los Angeles, CA, 90095, USA
- Neuroscience Interdepartmental Program, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Gabriella H Sigal
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Catherine M Cahill
- MacDonald Research Laboratory Building, Department of Psychiatry and Biobehavioral Sciences, Shirley and Stefan Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, 675 Charles E Young Drive South, Office 2774, Los Angeles, CA, 90095, USA.
- Neuroscience Interdepartmental Program, University of California Los Angeles, Los Angeles, CA, 90095, USA.
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Ji G, Presto P, Kiritoshi T, Chen Y, Navratilova E, Porreca F, Neugebauer V. Chemogenetic Manipulation of Amygdala Kappa Opioid Receptor Neurons Modulates Amygdala Neuronal Activity and Neuropathic Pain Behaviors. Cells 2024; 13:705. [PMID: 38667320 PMCID: PMC11049235 DOI: 10.3390/cells13080705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/12/2024] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
Neuroplasticity in the central nucleus of the amygdala (CeA) plays a key role in the modulation of pain and its aversive component. The dynorphin/kappa opioid receptor (KOR) system in the amygdala is critical for averse-affective behaviors in pain conditions, but its mechanisms are not well understood. Here, we used chemogenetic manipulations of amygdala KOR-expressing neurons to analyze the behavioral consequences in a chronic neuropathic pain model. For the chemogenetic inhibition or activation of KOR neurons in the CeA, a Cre-inducible viral vector encoding Gi-DREADD (hM4Di) or Gq-DREADD (hM3Dq) was injected stereotaxically into the right CeA of transgenic KOR-Cre mice. The chemogenetic inhibition of KOR neurons expressing hM4Di with a selective DREADD actuator (deschloroclozapine, DCZ) in sham control mice significantly decreased inhibitory transmission, resulting in a shift of inhibition/excitation balance to promote excitation and induced pain behaviors. The chemogenetic activation of KOR neurons expressing hM3Dq with DCZ in neuropathic mice significantly increased inhibitory transmission, decreased excitability, and decreased neuropathic pain behaviors. These data suggest that amygdala KOR neurons modulate pain behaviors by exerting an inhibitory tone on downstream CeA neurons. Therefore, activation of these interneurons or blockade of inhibitory KOR signaling in these neurons could restore control of amygdala output and mitigate pain.
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Affiliation(s)
- Guangchen Ji
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 4th St., Lubbock, TX 79430, USA
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Peyton Presto
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 4th St., Lubbock, TX 79430, USA
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Takaki Kiritoshi
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 4th St., Lubbock, TX 79430, USA
| | - Yong Chen
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 4th St., Lubbock, TX 79430, USA
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Edita Navratilova
- Department of Pharmacology, Arizona Health Sciences Center, University of Arizona, Tucson, AZ 85721, USA
| | - Frank Porreca
- Department of Pharmacology, Arizona Health Sciences Center, University of Arizona, Tucson, AZ 85721, USA
| | - Volker Neugebauer
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 4th St., Lubbock, TX 79430, USA
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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5
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Ujcikova H, Lee YS, Roubalova L, Svoboda P. The impact of multifunctional enkephalin analogs and morphine on the protein changes in crude membrane fractions isolated from the rat brain cortex and hippocampus. Peptides 2024; 174:171165. [PMID: 38307418 DOI: 10.1016/j.peptides.2024.171165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/12/2024] [Accepted: 01/29/2024] [Indexed: 02/04/2024]
Abstract
Endogenous opioid peptides serve as potent analgesics through the opioid receptor (OR) activation. However, they often suffer from poor metabolic stability, low lipophilicity, and low blood-brain barrier permeability. Researchers have developed many strategies to overcome the drawbacks of current pain medications and unwanted biological effects produced by the interaction with opioid receptors. Here, we tested multifunctional enkephalin analogs LYS739 (MOR/DOR agonist and KOR partial antagonist) and LYS744 (MOR/DOR agonist and KOR full antagonist) under in vivo conditions in comparison with MOR agonist, morphine. We applied 2D electrophoretic resolution to investigate differences in proteome profiles of crude membrane (CM) fractions isolated from the rat brain cortex and hippocampus exposed to the drugs (10 mg/kg, seven days). Our results have shown that treatment with analog LYS739 induced the most protein changes in cortical and hippocampal samples. The identified proteins were mainly associated with energy metabolism, cell shape and movement, apoptosis, protein folding, regulation of redox homeostasis, and signal transduction. Among these, the isoform of mitochondrial ATP synthase subunit beta (ATP5F1B) was the only protein upregulation in the hippocampus but not in the brain cortex. Contrarily, the administration of analog LYS744 caused a small number of protein alterations in both brain parts. Our results indicate that the KOR full antagonism, together with MOR/DOR agonism of multifunctional opioid ligands, can be beneficial in treating chronic pain states by reducing changes in protein expression levels but retaining analgesic efficacy.
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Affiliation(s)
- Hana Ujcikova
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, Prague 4 14200, Czech Republic.
| | - Yeon Sun Lee
- Department of Pharmacology, University of Arizona, Tucson, AZ 85724, USA
| | - Lenka Roubalova
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, Prague 4 14200, Czech Republic
| | - Petr Svoboda
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, Prague 4 14200, Czech Republic
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6
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Khir NAM, Noh ASM, Long I, Zakaria R, Ismail CAN. Recent progress on anti-nociceptive effects of carbon monoxide releasing molecule-2 (CORM-2). Mol Cell Biochem 2024; 479:539-552. [PMID: 37106243 DOI: 10.1007/s11010-023-04749-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023]
Abstract
The role of carbon monoxide (CO) has evolved albeit controversial disputes on its toxicity. This biological gasotransmitter participates in the endogenous regulation of neurotransmitters and neuropeptides released in the nervous system. Exogenous CO gas inhalation at a lower concentration has been the subject of investigations, which have revealed its biological homeostatic mechanisms and protective effects against many pathological conditions. This therapeutic procedure of CO is, however, limited due to its immediate release, which favours haemoglobin at a high affinity with the subsequent generation of toxic carboxyhaemoglobin in tissues. In order to address this problem, carbon monoxide releasing molecule-2 (CORM-2) or also known as tricarbonyldichlororuthenium II dimer is developed to liberate a controlled amount of CO in the biological systems. In this review, we examine several potential mechanisms exerted by this therapeutic compound to produce the anti-nociceptive effect that has been demonstrated in previous studies. This review could shed light on the role of CORM-2 to reduce pain, especially in cases of chronic and neuropathic pain.
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Affiliation(s)
- Nurul Ajilah Mohamed Khir
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia
- International Medical School, Management and Science University, 40100, Shah Alam, Selangor, Malaysia
| | - Ain' Sabreena Mohd Noh
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Idris Long
- Biomedicine Programme, School of Health Sciences, Universiti Sains Malaysia Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Rahimah Zakaria
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Che Aishah Nazariah Ismail
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia.
- Brain and Behaviour Cluster, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia.
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Huang P, Ho CK, Cao D, Inan S, Rawls SM, Li M, Huang B, Pagare PP, Townsend EA, Poklis JL, Halquist MS, Banks M, Zhang Y, Liu-Chen LY. NCP, a dual kappa and mu opioid receptor agonist, is a potent analgesic against inflammatory pain without reinforcing or aversive properties. J Pharmacol Exp Ther 2024; 389:JPET-AR-2023-001870. [PMID: 38409113 PMCID: PMC10949162 DOI: 10.1124/jpet.123.001870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 02/28/2024] Open
Abstract
While agonists of mu (MOR) and kappa (KOR) opioid receptors have analgesic effects, they produce euphoria and dysphoria, respectively. Other side effects include respiratory depression and addiction for MOR agonists and sedation for KOR agonists. We reported that 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-{[4'-(2'-cyanopyridyl)]carboxamido}cmorphinan (NCP) displayed potent KOR full agonist and MOR partial agonist activities (58%) with 6.5x KOR-over-MOR selectivity in vitro Herein, we characterized pharmacological effects of NCP in rodents. In mice, NCP exerted analgesic effects against inflammatory pain in both the formalin test and the acetic acid writhing test, with A50 values of 47.6 and 14.4 microg/kg (s.c.), respectively. The analgesic effects in the acetic acid writhing test were mediated by the KOR. NCP at doses much higher than those effective in reducing inflammatory pain did not produce antinociception in the hot plate and tail flick tests, inhibit compound 48/80-induced scratching, cause conditioned place aversion (CPA) or preference, impair rotarod performance, inhibit locomotor activity, cause respiratory depression, or precipitate morphine withdrawal. However, NCP (10~100 microg/kg) inhibited gastrointestinal transit with a maximum of ~40% inhibition. In MOR knockout mice, NCP caused CPA, demonstrating that its lack of CPA is due to combined actions on the MOR and KOR. Following s.c. injection, NCP penetrated into the mouse brain. In rats trained to self-administer heroin, NCP (1~320 microg/kg/infusion) did not function as a reinforcer. Thus, NCP produces potent analgesic effects via KOR without side effects except constipation. Therefore, dual full KOR/partial MOR agonists with moderate KOR-over-MOR selectivity may be promising as non-addictive analgesics for inflammatory pain. Significance Statement Developing non-addictive analgesics is crucial for reducing opioid overdose deaths, minimizing drug misuse, and promoting safer pain management practices. Herein, pharmacology of a potential non-addictive analgesic, NCP, is reported. NCP has full KOR agonist / partial MOR agonist activities with a 6.5 x selectivity for KOR over MOR. Unlike MOR agonists, analgesic doses of NCP do not lead to self-administration or respiratory depression. Furthermore, NCP does not produce aversion, hypolocomotion, or motor incoordination, side effects typically associated with KOR activation.
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Affiliation(s)
- Peng Huang
- Temple University Lewis Katz School of Medicine, United States
| | - Conrad K Ho
- Temple University Lewis Katz School of Medicine, United States
| | - Danni Cao
- Temple University Lewis Katz School of Medicine, United States
| | - Saadet Inan
- Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Lewis Katz School of Medicine, Temple University, United States
| | - Scott M Rawls
- Temple University Lewis Katz School of Medicine, United States
| | - Mengchu Li
- Virginia Commonwealth University School of Pharmacy, United States
| | - Boshi Huang
- Virginia Commonwealth University School of Pharmacy, United States
| | - Piyusha P Pagare
- Virginia Commonwealth University School of Pharmacy, United States
| | | | | | | | - Matthew Banks
- Virginia Commonwealth University School of Medicine, United States
| | - Yan Zhang
- Virginia Commonwealth University School of Pharmacy, United States
| | - Lee-Yuan Liu-Chen
- Center for Substance Abuse Research, Temple University Lewis Katz School of Medicine, United States
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8
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Costa AR, Tavares I, Martins I. How do opioids control pain circuits in the brainstem during opioid-induced disorders and in chronic pain? Implications for the treatment of chronic pain. Pain 2024; 165:324-336. [PMID: 37578500 DOI: 10.1097/j.pain.0000000000003026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 07/07/2023] [Indexed: 08/15/2023]
Abstract
ABSTRACT Brainstem areas involved in descending pain modulation are crucial for the analgesic actions of opioids. However, the role of opioids in these areas during tolerance, opioid-induced hyperalgesia (OIH), and in chronic pain settings remains underappreciated. We conducted a revision of the recent studies performed in the main brainstem areas devoted to descending pain modulation with a special focus on the medullary dorsal reticular nucleus (DRt), as a distinctive pain facilitatory area and a key player in the diffuse noxious inhibitory control paradigm. We show that maladaptive processes within the signaling of the µ-opioid receptor (MOR), which entail desensitization and a switch to excitatory signaling, occur in the brainstem, contributing to tolerance and OIH. In the context of chronic pain, the alterations found are complex and depend on the area and model of chronic pain. For example, the downregulation of MOR and δ-opioid receptor (DOR) in some areas, including the DRt, during neuropathic pain likely contributes to the inefficacy of opioids. However, the upregulation of MOR and DOR, at the rostral ventromedial medulla, in inflammatory pain models, suggests therapeutic avenues to explore. Mechanistically, the rationale for the diversity and complexity of alterations in the brainstem is likely provided by the alternative splicing of opioid receptors and the heteromerization of MOR. In conclusion, this review emphasizes how important it is to consider the effects of opioids at these circuits when using opioids for the treatment of chronic pain and for the development of safer and effective opioids.
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Affiliation(s)
- Ana Rita Costa
- Department of Biomedicine, Unit of Experimental Biology, Faculty of Medicine, University of Porto, Porto, Portugal
- IBMC-Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- I3S- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal. Costa is now with the Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden and Science for Life Laboratory, Solna, Sweden
| | - Isaura Tavares
- Department of Biomedicine, Unit of Experimental Biology, Faculty of Medicine, University of Porto, Porto, Portugal
- IBMC-Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- I3S- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal. Costa is now with the Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden and Science for Life Laboratory, Solna, Sweden
| | - Isabel Martins
- Department of Biomedicine, Unit of Experimental Biology, Faculty of Medicine, University of Porto, Porto, Portugal
- IBMC-Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- I3S- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal. Costa is now with the Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden and Science for Life Laboratory, Solna, Sweden
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9
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Lorente JD, Cuitavi J, Rullo L, Candeletti S, Romualdi P, Hipólito L. Sex-dependent effect of inflammatory pain on negative affective states is prevented by kappa opioid receptors blockade in the nucleus accumbens shell. Neuropharmacology 2024; 242:109764. [PMID: 37879455 DOI: 10.1016/j.neuropharm.2023.109764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/13/2023] [Accepted: 10/15/2023] [Indexed: 10/27/2023]
Abstract
Pain comorbidities include several psychological disorders, such as anxiety and anhedonia. However, the way pain affects male and female individuals and by which mechanism is not well understood. Previous research shows that pain induces alterations in the dynorphinergic pathway within the mesocorticolimbic system (MCLS), together with a relationship between corticotropin-releasing system and dynorphin release in the MCLS. Here, we analyse the sex and time course-dependent effects of pain on negative affect. Additionally, we study the implication of dynorphinergic and corticotropin releasing factor in these pain related behaviours. We used behavioural pharmacology and biochemical tools to characterise negative affective states induced by inflammatory pain in male and female rats, and the alterations in the dynorphinergic and the corticotropin systems within the MCLS. Female rats showed persistent anxiety-like and reversible anhedonia-like behaviours derived from inflammatory pain. Additionally, we found alterations in dynorphin and corticotropin releasing factor in NAc and amygdala, which suggests sex-dependent dynamic adaptations. Finally blockade on the kappa opioid receptor in the NAc confirmed its role in pain-induced anxiety-like behaviour in female rats. Our results show sex and time-dependent anxiety- and anhedonia-like behaviours induced by the presence of pain in female rats. Furthermore, we replicated previous data, pointing to the KOR/DYN recruitment in the NAc as a key neurological substrate mediating pain-induced behavioural alterations. This research studies the mechanisms underlying these behaviours, to better understand the emotional dimension of pain.
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Affiliation(s)
- J D Lorente
- Department of Pharmacy and Pharmaceutical Technology and Parasitology, University of Valencia, Valencia, Spain
| | - J Cuitavi
- Department of Pharmacy and Pharmaceutical Technology and Parasitology, University of Valencia, Valencia, Spain; University Institute of Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain
| | - L Rullo
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Italy
| | - S Candeletti
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Italy
| | - P Romualdi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Italy
| | - L Hipólito
- Department of Pharmacy and Pharmaceutical Technology and Parasitology, University of Valencia, Valencia, Spain; University Institute of Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain.
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10
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Lançon K, Séguéla P. Dysregulated neuromodulation in the anterior cingulate cortex in chronic pain. Front Pharmacol 2023; 14:1289218. [PMID: 37954846 PMCID: PMC10634228 DOI: 10.3389/fphar.2023.1289218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 10/09/2023] [Indexed: 11/14/2023] Open
Abstract
Chronic pain is a significant global socioeconomic burden with limited long-term treatment options. The intractable nature of chronic pain stems from two primary factors: the multifaceted nature of pain itself and an insufficient understanding of the diverse physiological mechanisms that underlie its initiation and maintenance, in both the peripheral and central nervous systems. The development of novel non-opioidergic analgesic approaches is contingent on our ability to normalize the dysregulated nociceptive pathways involved in pathological pain processing. The anterior cingulate cortex (ACC) stands out due to its involvement in top-down modulation of pain perception, its abnormal activity in chronic pain conditions, and its contribution to cognitive functions frequently impaired in chronic pain states. Here, we review the roles of the monoamines dopamine (DA), norepinephrine (NE), serotonin (5-HT), and other neuromodulators in controlling the activity of the ACC and how chronic pain alters their signaling in ACC circuits to promote pathological hyperexcitability. Additionally, we discuss the potential of targeting these monoaminergic pathways as a therapeutic strategy for treating the cognitive and affective symptoms associated with chronic pain.
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Affiliation(s)
| | - Philippe Séguéla
- Department of Neurology and Neurosurgery, Alan Edwards Centre for Research on Pain, Montréal Neurological Institute, McGill University, Montréal, QC, Canada
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11
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Olabarrieta E, Totorikaguena L, Matorras R, Agirregoitia E, Agirregoitia N. Delta and kappa opioid receptors in human endometrium during the menstrual cycle: Expression and localization. Eur J Obstet Gynecol Reprod Biol 2023; 283:68-73. [PMID: 36801594 DOI: 10.1016/j.ejogrb.2023.01.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 11/11/2022] [Accepted: 01/25/2023] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Endogenous opioid peptides were reported to be involved in the regulation of reproductive physiology and their precursors and receptors were described in many of the male and female reproductive tissues. Mu opioid receptor (MOR) was described in human endometrial cells and its expression and localization changed during the menstrual cycle. However, there is no data from the distribution of the other opioid receptors: Delta (DOR) and Kappa (KOR). The objective of the present work was to analyze the dynamics of expression and localization of DOR and KOR in human endometrium throughout the menstrual cycle. STUDY DESIGN Human endometrial samples from different menstrual cycle phases were analyzed by immunohistochemistry. RESULTS DOR and KOR were present in all samples analyzed and the protein expression and localization changed throughout the menstrual cycle. Both receptor expression increased during the late proliferative phase and decreased during the late secretory-one, especially in the luminal epithelium. DOR expression was generally higher than KOR expression in all cell compartments. CONCLUSIONS The presence of DOR and KOR in human endometrium and their dynamic changes during the menstrual cycle join the results previously obtained in MOR suggesting a possible role of opioids in reproduction events related to the human endometrium.
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Affiliation(s)
- Estibaliz Olabarrieta
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Bizkaia; Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, ISCIII, Spain
| | - Lide Totorikaguena
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Bizkaia
| | - Roberto Matorras
- Human Reproduction Unit, Cruces University Hospital, Biocruces, IVIRMA, IVI Bilbao, Leioa, University of the Basque Country (UPV/EHU), Bizkaia
| | - Ekaitz Agirregoitia
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Bizkaia
| | - Naiara Agirregoitia
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Bizkaia.
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12
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Margolis EB, Moulton MG, Lambeth PS, O'Meara MJ. The life and times of endogenous opioid peptides: Updated understanding of synthesis, spatiotemporal dynamics, and the clinical impact in alcohol use disorder. Neuropharmacology 2023; 225:109376. [PMID: 36516892 PMCID: PMC10548835 DOI: 10.1016/j.neuropharm.2022.109376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 12/03/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022]
Abstract
The opioid G-protein coupled receptors (GPCRs) strongly modulate many of the central nervous system structures that contribute to neurological and psychiatric disorders including pain, major depressive disorder, and substance use disorders. To better treat these and related diseases, it is essential to understand the signaling of their endogenous ligands. In this review, we focus on what is known and unknown about the regulation of the over two dozen endogenous peptides with high affinity for one or more of the opioid receptors. We briefly describe which peptides are produced, with a particular focus on the recently proposed possible synthesis pathways for the endomorphins. Next, we describe examples of endogenous opioid peptide expression organization in several neural circuits and how they appear to be released from specific neural compartments that vary across brain regions. We discuss current knowledge regarding the strength of neural activity required to drive endogenous opioid peptide release, clues about how far peptides diffuse from release sites, and their extracellular lifetime after release. Finally, as a translational example, we discuss the mechanisms of action of naltrexone (NTX), which is used clinically to treat alcohol use disorder. NTX is a synthetic morphine analog that non-specifically antagonizes the action of most endogenous opioid peptides developed in the 1960s and FDA approved in the 1980s. We review recent studies clarifying the precise endogenous activity that NTX prevents. Together, the works described here highlight the challenges and opportunities the complex opioid system presents as a therapeutic target.
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Affiliation(s)
- Elyssa B Margolis
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, CA, USA; Neuroscience Graduate Program, University of California, San Francisco, CA, USA.
| | - Madelyn G Moulton
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, CA, USA
| | - Philip S Lambeth
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, San Francisco, CA, USA
| | - Matthew J O'Meara
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, 48109, USA
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13
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Ito H, Navratilova E, Vagnerova B, Watanabe M, Kopruszinski C, Moreira de Souza LH, Yue X, Ikegami D, Moutal A, Patwardhan A, Khanna R, Yamazaki M, Guerrero M, Rosen H, Roberts E, Neugebauer V, Dodick DW, Porreca F. Chronic pain recruits hypothalamic dynorphin/kappa opioid receptor signalling to promote wakefulness and vigilance. Brain 2023; 146:1186-1199. [PMID: 35485490 PMCID: PMC10169443 DOI: 10.1093/brain/awac153] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/08/2022] [Accepted: 03/31/2022] [Indexed: 11/13/2022] Open
Abstract
Increased vigilance in settings of potential threats or in states of vulnerability related to pain is important for survival. Pain disrupts sleep and conversely, sleep disruption enhances pain, but the underlying mechanisms remain unknown. Chronic pain engages brain stress circuits and increases secretion of dynorphin, an endogenous ligand of the kappa opioid receptor (KOR). We therefore hypothesized that hypothalamic dynorphin/KOR signalling may be a previously unknown mechanism that is recruited in pathological conditions requiring increased vigilance. We investigated the role of KOR in wakefulness, non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep in freely moving naïve mice and in mice with neuropathic pain induced by partial sciatic nerve ligation using EEG/EMG recordings. Systemic continuous administration of U69,593, a KOR agonist, over 5 days through an osmotic minipump decreased the amount of NREM and REM sleep and increased sleep fragmentation in naïve mice throughout the light-dark sleep cycle. We used KORcre mice to selectively express a Gi-coupled designer receptor activated by designer drugs (Gi-DREADD) in KORcre neurons of the hypothalamic paraventricular nucleus, a key node of the hypothalamic-pituitary-adrenal stress response. Sustained activation of Gi-DREADD with clozapine-N-oxide delivered in drinking water over 4 days, disrupted sleep in these mice in a similar way as systemic U69,593. Mice with chronic neuropathic pain also showed disrupted NREM and total sleep that was normalized by systemic administration of two structurally different KOR antagonists, norbinaltorphimine and NMRA-140, currently in phase II clinical development, or by CRISPR/Cas9 editing of paraventricular nucleus KOR, consistent with endogenous KOR activation disrupting sleep in chronic pain. Unexpectedly, REM sleep was diminished by either systemic KOR antagonist or by CRISPR/Cas9 editing of paraventricular nucleus KOR in sham-operated mice. Our findings reveal previously unknown physiological and pathophysiological roles of dynorphin/KOR in eliciting arousal. Physiologically, dynorphin/KOR signalling affects transitions between sleep stages that promote REM sleep. Furthermore, while KOR antagonists do not promote somnolence in the absence of pain, they normalized disrupted sleep in chronic pain, revealing a pathophysiological role of KOR signalling that is selectively recruited to promote vigilance, increasing chances of survival. Notably, while this mechanism is likely beneficial in the short-term, disruption of the homeostatic need for sleep over longer periods may become maladaptive resulting in sustained pain chronicity. A novel approach for treatment of chronic pain may thus result from normalization of chronic pain-related sleep disruption by KOR antagonism.
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Affiliation(s)
- Hisakatsu Ito
- Department of Pharmacology, University of Arizona, Tucson, USA
- Department of Anesthesiology, University of Toyama, Toyama, Japan
| | - Edita Navratilova
- Department of Pharmacology, University of Arizona, Tucson, USA
- Department of Collaborative Research, Mayo Clinic, Scottsdale, USA
| | | | - Moe Watanabe
- Department of Pharmacology, University of Arizona, Tucson, USA
| | | | | | - Xu Yue
- Department of Pharmacology, University of Arizona, Tucson, USA
| | - Daigo Ikegami
- Department of Pharmacology, University of Arizona, Tucson, USA
| | - Aubin Moutal
- Department of Pharmacology, University of Arizona, Tucson, USA
| | - Amol Patwardhan
- Department of Pharmacology, University of Arizona, Tucson, USA
| | - Rajesh Khanna
- Department of Pharmacology, University of Arizona, Tucson, USA
| | | | - Miguel Guerrero
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, USA
| | - Hugh Rosen
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, USA
| | - Ed Roberts
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, USA
| | - Volker Neugebauer
- Department of Pharmacology and Neuroscience and Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, USA
| | | | - Frank Porreca
- Department of Pharmacology, University of Arizona, Tucson, USA
- Department of Collaborative Research, Mayo Clinic, Scottsdale, USA
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14
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West AM, Holleran KM, Jones SR. Kappa Opioid Receptors Reduce Serotonin Uptake and Escitalopram Efficacy in the Mouse Substantia Nigra Pars Reticulata. Int J Mol Sci 2023; 24:ijms24032080. [PMID: 36768403 PMCID: PMC9916942 DOI: 10.3390/ijms24032080] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
The serotonin and kappa opioid receptor (KOR) systems are strongly implicated in disorders of negative affect, such as anxiety and depression. KORs expressed on axon terminals inhibit the release of neurotransmitters, including serotonin. The substantia nigra pars reticulata (SNr) is involved in regulating affective behaviors. It receives the densest serotonergic innervation in the brain and has high KOR expression; however, the influence of KORs on serotonin transmission in this region is yet to be explored. Here, we used ex vivo fast-scan cyclic voltammetry (FSCV) to investigate the effects of a KOR agonist, U50, 488 (U50), and a selective serotonin reuptake inhibitor, escitalopram, on serotonin release and reuptake in the SNr. U50 alone reduced serotonin release and uptake, and escitalopram alone augmented serotonin release and slowed reuptake, while pretreatment with U50 blunted both the release and uptake effects of escitalopram. Here, we show that the KOR influences serotonin signaling in the SNr in multiple ways and short-term activation of the KOR alters serotonin responses to escitalopram. These interactions between KORs and serotonin may contribute to the complexity in the responses to treatments for disorders of negative affect. Ultimately, the KOR system may prove to be a promising pharmacological target, alongside traditional antidepressant treatments.
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15
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Lee SJ, Logsdon AF, Yagi M, Baskin BM, Peskind ER, Raskind MM, Cook DG, Schindler AG. The dynorphin/kappa opioid receptor mediates adverse immunological and behavioral outcomes induced by repetitive blast trauma. J Neuroinflammation 2022; 19:288. [PMID: 36463243 PMCID: PMC9719647 DOI: 10.1186/s12974-022-02643-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 11/11/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Adverse pathophysiological and behavioral outcomes related to mild traumatic brain injury (mTBI), posttraumatic stress disorder (PTSD), and chronic pain are common following blast exposure and contribute to decreased quality of life, but underlying mechanisms and prophylactic/treatment options remain limited. The dynorphin/kappa opioid receptor (KOR) system helps regulate behavioral and inflammatory responses to stress and injury; however, it has yet to be investigated as a potential mechanism in either humans or animals exposed to blast. We hypothesized that blast-induced KOR activation mediates adverse outcomes related to inflammation and affective behavioral response. METHODS C57Bl/6 adult male mice were singly or repeatedly exposed to either sham (anesthesia only) or blast delivered by a pneumatic shock tube. The selective KOR antagonist norBNI or vehicle (saline) was administered 72 h prior to repetitive blast or sham exposure. Serum and brain were collected 10 min or 4 h post-exposure for dynorphin A-like immunoreactivity and cytokine measurements, respectively. At 1-month post-exposure, mice were tested in a series of behavioral assays related to adverse outcomes reported by humans with blast trauma. RESULTS Repetitive but not single blast exposure resulted in increased brain dynorphin A-like immunoreactivity. norBNI pretreatment blocked or significantly reduced blast-induced increase in serum and brain cytokines, including IL-6, at 4 h post exposure and aversive/anxiety-like behavioral dysfunction at 1-month post-exposure. CONCLUSIONS Our findings demonstrate a previously unreported role for the dynorphin/KOR system as a mediator of biochemical and behavioral dysfunction following repetitive blast exposure and highlight this system as a potential prophylactic/therapeutic treatment target.
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Affiliation(s)
- Suhjung Janet Lee
- grid.413919.70000 0004 0420 6540VA Northwest Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, S182, 1660 South Columbian Way, Seattle, WA 98108 USA
| | - Aric F. Logsdon
- grid.413919.70000 0004 0420 6540VA Northwest Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, S182, 1660 South Columbian Way, Seattle, WA 98108 USA ,grid.34477.330000000122986657Department of Medicine, Division of Gerontology and Geriatric Medicine, University of Washington, Seattle, WA 98195 USA
| | - Mayumi Yagi
- grid.413919.70000 0004 0420 6540VA Northwest Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, S182, 1660 South Columbian Way, Seattle, WA 98108 USA
| | - Britahny M. Baskin
- grid.34477.330000000122986657Graduate Program in Neuroscience, University of Washington, Seattle, WA 98195 USA
| | - Elaine. R. Peskind
- grid.413919.70000 0004 0420 6540VA Northwest Mental Illness Research, Education, and Clinical Center, VA Puget Sound Health Care System, Seattle, WA 98108 USA ,grid.34477.330000000122986657Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195 USA
| | - Murray M. Raskind
- grid.413919.70000 0004 0420 6540VA Northwest Mental Illness Research, Education, and Clinical Center, VA Puget Sound Health Care System, Seattle, WA 98108 USA ,grid.34477.330000000122986657Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195 USA
| | - David G. Cook
- grid.413919.70000 0004 0420 6540VA Northwest Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, S182, 1660 South Columbian Way, Seattle, WA 98108 USA ,grid.34477.330000000122986657Graduate Program in Neuroscience, University of Washington, Seattle, WA 98195 USA ,grid.34477.330000000122986657Department of Medicine, Division of Gerontology and Geriatric Medicine, University of Washington, Seattle, WA 98195 USA ,grid.34477.330000000122986657Department of Pharmacology, University of Washington, Seattle, WA 98195 USA
| | - Abigail. G. Schindler
- grid.413919.70000 0004 0420 6540VA Northwest Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, S182, 1660 South Columbian Way, Seattle, WA 98108 USA ,grid.34477.330000000122986657Graduate Program in Neuroscience, University of Washington, Seattle, WA 98195 USA ,grid.34477.330000000122986657Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195 USA ,grid.34477.330000000122986657Department of Medicine, Division of Gerontology and Geriatric Medicine, University of Washington, Seattle, WA 98195 USA
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16
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Mitra S, Thomas SA, Martin JA, Williams J, Woodhouse K, Chandra R, Li JX, Lobo MK, Sim FJ, Dietz DM. EGR3 regulates opioid-related nociception and motivation in male rats. Psychopharmacology (Berl) 2022; 239:3539-3550. [PMID: 36098762 PMCID: PMC10094589 DOI: 10.1007/s00213-022-06226-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 08/24/2022] [Indexed: 01/11/2023]
Abstract
Chronic pain can be a debilitating condition, leading to profound changes in nearly every aspect of life. However, the reliance on opioids such as oxycodone for pain management is thought to initiate dependence and addiction liability. The neurobiological intersection at which opioids relieve pain and possibly transition to addiction is poorly understood. Using RNA sequencing pathway analysis in rats with complete Freund's adjuvant (CFA)-induced chronic inflammation, we found that the transcriptional signatures in the medial prefrontal cortex (mPFC; a brain region where pain and reward signals integrate) elicited by CFA in combination with oxycodone differed from those elicited by CFA or oxycodone alone. However, the expression of Egr3 was augmented in all animals receiving oxycodone. Furthermore, virus-mediated overexpression of EGR3 in the mPFC increased mechanical pain relief but not the affective aspect of pain in animals receiving oxycodone, whereas pharmacological inhibition of EGR3 via NFAT attenuated mechanical pain relief. Egr3 overexpression also increased the motivation to obtain oxycodone infusions in a progressive ratio test without altering the acquisition or maintenance of oxycodone self-administration. Taken together, these data suggest that EGR3 in the mPFC is at the intersection of nociceptive and addictive-like behaviors.
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Affiliation(s)
- Swarup Mitra
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA.
- Department of Biomedical Sciences, John C. Edwards School of Medicine, Marshall University, 1700, 3rd Avenue, Huntington, WV, 25755, USA.
| | - Shruthi A Thomas
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Jennifer A Martin
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Jamal Williams
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Kristen Woodhouse
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Ramesh Chandra
- Department of Anatomy and Neurobiology, University of Maryland, Baltimore, MD, USA
| | - Jun Xu Li
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Mary Kay Lobo
- Department of Anatomy and Neurobiology, University of Maryland, Baltimore, MD, USA
| | - Fraser J Sim
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - David M Dietz
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA.
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17
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Coutinho EA, Esparza LA, Hudson AD, Rizo N, Steffen P, Kauffman AS. Conditional Deletion of KOR (Oprk1) in Kisspeptin Cells Does Not Alter LH Pulses, Puberty, or Fertility in Mice. Endocrinology 2022; 163:6763672. [PMID: 36260530 DOI: 10.1210/endocr/bqac175] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Indexed: 01/26/2023]
Abstract
Classic pharmacological studies suggested that endogenous dynorphin-KOR signaling is important for reproductive neuroendocrine regulation. With the seminal discovery of an interconnected network of hypothalamic arcuate neurons co-expressing kisspeptin, neurokinin B, and dynorphin (KNDy neurons), the KNDy hypothesis was developed to explain how gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) pulses are generated. Key to this hypothesis is dynorphin released from KNDy neurons acting in a paracrine manner on other KNDy neurons via kappa opioid receptor (KOR) signaling to terminate neural "pulse" events. While in vitro evidence supports this aspect of the KNDy hypothesis, a direct in vivo test of the necessity of KOR signaling in kisspeptin neurons for proper LH secretion has been lacking. We therefore conditionally knocked out KOR selectively from kisspeptin neurons of male and female mice and tested numerous reproductive measures, including in vivo LH pulse secretion. Surprisingly, despite validating successful knockout of KOR in kisspeptin neurons, we found no significant effect of kisspeptin cell-specific deletion of KOR on any measure of puberty, LH pulse parameters, LH surges, follicle-stimulating hormone (FSH) levels, estrous cycles, or fertility. These outcomes suggest that the KNDy hypothesis, while sufficient normally, may not be the only neural mechanism for sculpting GnRH and LH pulses, supported by recent findings in humans and mice. Thus, besides normally acting via KOR in KNDy neurons, endogenous dynorphin and other opioids may, under some conditions, regulate LH and FSH secretion via KOR in non-kisspeptin cells or perhaps via non-KOR pathways. The current models for GnRH and LH pulse generation should be expanded to consider such alternate mechanisms.
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Affiliation(s)
- Eulalia A Coutinho
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Lourdes A Esparza
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Alexandra D Hudson
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Nathanael Rizo
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Paige Steffen
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Alexander S Kauffman
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
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18
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Higginbotham JA, Markovic T, Massaly N, Morón JA. Endogenous opioid systems alterations in pain and opioid use disorder. Front Syst Neurosci 2022; 16:1014768. [PMID: 36341476 PMCID: PMC9628214 DOI: 10.3389/fnsys.2022.1014768] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/26/2022] [Indexed: 11/25/2022] Open
Abstract
Decades of research advances have established a central role for endogenous opioid systems in regulating reward processing, mood, motivation, learning and memory, gastrointestinal function, and pain relief. Endogenous opioid systems are present ubiquitously throughout the central and peripheral nervous system. They are composed of four families, namely the μ (MOPR), κ (KOPR), δ (DOPR), and nociceptin/orphanin FQ (NOPR) opioid receptors systems. These receptors signal through the action of their endogenous opioid peptides β-endorphins, dynorphins, enkephalins, and nociceptins, respectfully, to maintain homeostasis under normal physiological states. Due to their prominent role in pain regulation, exogenous opioids-primarily targeting the MOPR, have been historically used in medicine as analgesics, but their ability to produce euphoric effects also present high risks for abuse. The ability of pain and opioid use to perturb endogenous opioid system function, particularly within the central nervous system, may increase the likelihood of developing opioid use disorder (OUD). Today, the opioid crisis represents a major social, economic, and public health concern. In this review, we summarize the current state of the literature on the function, expression, pharmacology, and regulation of endogenous opioid systems in pain. Additionally, we discuss the adaptations in the endogenous opioid systems upon use of exogenous opioids which contribute to the development of OUD. Finally, we describe the intricate relationship between pain, endogenous opioid systems, and the proclivity for opioid misuse, as well as potential advances in generating safer and more efficient pain therapies.
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Affiliation(s)
- Jessica A. Higginbotham
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States,Pain Center, Washington University in St. Louis, St. Louis, MO, United States,School of Medicine, Washington University in St. Louis, St. Louis, MO, United States,*Correspondence: Jessica A. Higginbotham,
| | - Tamara Markovic
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Nicolas Massaly
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States,Pain Center, Washington University in St. Louis, St. Louis, MO, United States,School of Medicine, Washington University in St. Louis, St. Louis, MO, United States
| | - Jose A. Morón
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States,Pain Center, Washington University in St. Louis, St. Louis, MO, United States,School of Medicine, Washington University in St. Louis, St. Louis, MO, United States,Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States,Department of Psychiatry, Washington University in St. Louis, St. Louis, MO, United States
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19
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Mechanisms Underlining Inflammatory Pain Sensitivity in Mice Selected for High and Low Stress-Induced Analgesia-The Role of Endocannabinoids and Microglia. Int J Mol Sci 2022; 23:ijms231911686. [PMID: 36232988 PMCID: PMC9570076 DOI: 10.3390/ijms231911686] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/24/2022] [Accepted: 09/29/2022] [Indexed: 11/05/2022] Open
Abstract
In this work we strived to determine whether endocannabinoid system activity could account for the differences in acute inflammatory pain sensitivity in mouse lines selected for high (HA) and low (LA) swim-stress-induced analgesia (SSIA). Mice received intraplantar injections of 5% formalin and the intensity of nocifensive behaviours was scored. To assess the contribution of the endocannabinoid system, mice were intraperitoneally (i.p.) injected with rimonabant (0.3–3 mg/kg) prior to formalin. Minocycline (45 and 100 mg/kg, i.p.) was administered to investigate microglial activation. The possible involvement of the endogenous opioid system was investigated with naloxone (1 mg/kg, i.p.). Cannabinoid receptor types 1 and 2 (Cnr1, Cnr2) and opioid receptor subtype (Oprm1, Oprd1, Oprk1) mRNA levels were quantified by qPCR in the structures of the central nociceptive circuit. Levels of anandamide (AEA) and 2-arachidonoylglycerol (2-AG) were measured by liquid chromatography coupled with the mass spectrometry method (LC-MS/MS). In the interphase, higher pain thresholds in the HA mice correlated with increased spinal anandamide and 2-AG release and higher Cnr1 transcription. Downregulation of Oprd1 and Oprm1 mRNA was noted in HA and LA mice, respectively, however no differences in naloxone sensitivity were observed in either line. As opposed to the LA mice, inflammatory pain sensitivity in the HA mice in the tonic phase was attributed to enhanced microglial activation, as evidenced by enhanced Aif1 and Il-1β mRNA levels. To conclude, Cnr1 inhibitory signaling is one mechanism responsible for decreased pain sensitivity in HA mice in the interphase, while increased microglial activation corresponds to decreased pain thresholds in the tonic inflammatory phase.
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20
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Walwyn WM, Valenza M. Editorial: Kappa opioid receptors revealed: Disentangling the pharmacology to open up new therapeutic strategies. Front Pharmacol 2022; 13:973780. [PMID: 36034837 PMCID: PMC9413185 DOI: 10.3389/fphar.2022.973780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Wendy Margaret Walwyn
- Jane & Terry Semel Institute for Neuroscience and Human Behavior, Los Angeles, CA, United States
| | - Marta Valenza
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Rome, Italy
- *Correspondence: Marta Valenza,
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21
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Targeting G protein coupled receptors for alleviating neuropathic pain. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 193:99-117. [PMID: 36357081 DOI: 10.1016/bs.pmbts.2022.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Pain sensation is a normal physiological response to alert and prevent further tissue damage. It involves the perception of external stimuli by somatosensory neurons, then transmission of the message to various other types of neurons present in the spinal cord and brain to generate an appropriate response. Currently available analgesics exhibit very modest efficacy, and that too in only a subset of patients with chronic pain conditions, particularly neuropathic pain. The G protein-coupled receptors (GPCRs) are expressed on presynaptic, postsynaptic terminals, and soma of somatosensory neurons, which binds to various types of ligands to modulate neuronal activity and thus pain sensation in both directions. Fundamentally, neuropathic pain arises due to aberrant neuronal plasticity, which includes the sensitization of peripheral primary afferents (dorsal root ganglia and trigeminal ganglia) and the sensitization of central nociceptive neurons in the spinal cord or trigeminal nucleus or brain stem and cortex. Owing to the expression profiles of GPCRs in somatosensory neurons and other neuroanatomical regions involved in pain processing and transmission, this article shall focus only on four families of GPCRs: 1- Opioid receptors, 2-Cannabinoid receptors, 3-Adenosine receptors, and 4-Chemokine receptors.
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22
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de Laat B, Nabulsi N, Huang Y, O'Malley SS, Morris ED, Krishnan-Sarin S. Differences in the association between kappa opioid receptors and pain among Black and White adults with alcohol use disorders. Alcohol Clin Exp Res 2022; 46:1348-1357. [PMID: 35633151 DOI: 10.1111/acer.14879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 05/05/2022] [Accepted: 05/24/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND The relationship between alcohol and pain is complex. Associations between pain and alcohol use disorder (AUD) vary by race, but the underlying biological basis is not understood. We examined the association of the kappa opioid receptor (KOR) with responses to the cold-pressor test (CPT), before and after treatment with the opioid antagonist naltrexone, among individuals with AUD who self-identified as Black or White. METHODS Thirty-seven individuals (12 Black, 24 White, and 1 Multiracial) with AUD participated in two CPTs, separated by 1 week during which they received naltrexone 100 mg daily. During each CPT, pain reporting threshold (PRT), average pain increase rate (APIR), relative pain recovery (RPR), and alcohol craving were recorded. KOR availability was measured using [11 C]-LY2795050 positron emission tomography (PET) prior to treatment with naltrexone. RESULTS Black participants reported higher PRT and APIR than White participants during the CPT before, but not after, naltrexone treatment. Among Black participants, KOR availability was positively associated with PRT and APIR before, but not after naltrexone. Greater KOR availability was associated with faster RPR for White, but not Black, participants. The CPT induced more alcohol craving in Black than White participants, particularly in individuals with low KOR availability, an effect that was not attenuated by naltrexone. CONCLUSIONS KOR involvement and naltrexone effects on responses to the CPT were different between Black and White participants. These preliminary findings suggest that further exploration of the differences in the opioid system and pain among Black and White individuals with AUD and their relationship with naltrexone's effects is warranted.
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Affiliation(s)
- Bart de Laat
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut, USA
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut, USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut, USA
| | | | - Evan D Morris
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut, USA.,Department of Psychiatry, Yale University, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA
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23
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Yakhnitsa V, Ji G, Hein M, Presto P, Griffin Z, Ponomareva O, Navratilova E, Porreca F, Neugebauer V. Kappa Opioid Receptor Blockade in the Amygdala Mitigates Pain Like-Behaviors by Inhibiting Corticotropin Releasing Factor Neurons in a Rat Model of Functional Pain. Front Pharmacol 2022; 13:903978. [PMID: 35694266 PMCID: PMC9177060 DOI: 10.3389/fphar.2022.903978] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/09/2022] [Indexed: 01/06/2023] Open
Abstract
Functional pain syndromes (FPS) occur in the absence of identifiable tissue injury or noxious events and include conditions such as migraine, fibromyalgia, and others. Stressors are very common triggers of pain attacks in various FPS conditions. It has been recently demonstrated that kappa opioid receptors (KOR) in the central nucleus of amygdala (CeA) contribute to FPS conditions, but underlying mechanisms remain unclear. The CeA is rich in KOR and encompasses major output pathways involving extra-amygdalar projections of corticotropin releasing factor (CRF) expressing neurons. Here we tested the hypothesis that KOR blockade in the CeA in a rat model of FPS reduces pain-like and nocifensive behaviors by restoring inhibition of CeA-CRF neurons. Intra-CeA administration of a KOR antagonist (nor-BNI) decreased mechanical hypersensitivity and affective and anxiety-like behaviors in a stress-induced FPS model. In systems electrophysiology experiments in anesthetized rats, intra-CeA application of nor-BNI reduced spontaneous firing and responsiveness of CeA neurons to peripheral stimulation. In brain slice whole-cell patch-clamp recordings, nor-BNI increased feedforward inhibitory transmission evoked by optogenetic and electrical stimulation of parabrachial afferents, but had no effect on monosynaptic excitatory transmission. Nor-BNI decreased frequency, but not amplitude, of spontaneous inhibitory synaptic currents, suggesting a presynaptic action. Blocking KOR receptors in stress-induced FPS conditions may therefore represent a novel therapeutic strategy.
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Affiliation(s)
- Vadim Yakhnitsa
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Guangchen Ji
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Matthew Hein
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Peyton Presto
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Zack Griffin
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Olga Ponomareva
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Edita Navratilova
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
| | - Frank Porreca
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
| | - Volker Neugebauer
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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24
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The Potential of Methocinnamox as a Future Treatment for Opioid Use Disorder: A Narrative Review. PHARMACY 2022; 10:pharmacy10030048. [PMID: 35645327 PMCID: PMC9149874 DOI: 10.3390/pharmacy10030048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/15/2022] [Accepted: 04/16/2022] [Indexed: 02/01/2023] Open
Abstract
The opioid epidemic is an ongoing public health crisis, and the United States health system is overwhelmed with increasing numbers of opioid-related overdoses. Methocinnamox (MCAM) is a novel mu opioid receptor antagonist with an extended duration of action. MCAM has potential to reduce the burden of the opioid epidemic by being used as an overdose rescue treatment and a long-term treatment for opioid use disorder (OUD). The currently available treatments for OUD include naloxone, naltrexone, and methadone. These treatments have certain limitations, which include short duration of action, patient non-compliance, and diversion. A narrative review was conducted using PubMed and Google Scholar databases covering the history of the opioid epidemic, pain receptors, current OUD treatments and the novel drug MCAM. MCAM could potentially be used as both a rescue and long-term treatment for opioid misuse. This is due to its pseudo-irreversible antagonism of the mu opioid receptor, abnormally long duration of action of nearly two weeks, and the possibility of using kappa or delta opioid receptor agonists for pain management during OUD treatment. MCAM’s novel pharmacokinetic and pharmacodynamic properties open a new avenue for treating opioid misuse.
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25
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Benarroch E. What Are the Interactions Between the Midbrain Dopamine System in Pain? Neurology 2022; 98:274-278. [PMID: 35165154 DOI: 10.1212/wnl.0000000000013253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 12/02/2021] [Indexed: 11/15/2022] Open
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26
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Massaly N, Markovic T, Creed M, Al-Hasani R, Cahill CM, Moron JA. Pain, negative affective states and opioid-based analgesics: Safer pain therapies to dampen addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2022; 157:31-68. [PMID: 33648672 DOI: 10.1016/bs.irn.2020.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Across centuries and civilizations opioids have been used to relieve pain. In our modern societies, opioid-based analgesics remain one of the most efficient treatments for acute pain. However, the long-term use of opioids can lead to the development of analgesic tolerance, opioid-induced hyperalgesia, opioid use disorders, and overdose, which can ultimately produce respiratory depressant effects with fatal consequences. In addition to the nociceptive sensory component of pain, negative affective states arising from persistent pain represent a risk factor for developing an opioid use disorder. Several studies have indicated that the increase in prescribed opioid analgesics since the 1990s represents the root of our current opioid epidemic. In this review, we will present our current knowledge on the endogenous opioid system within the pain neuroaxis and the plastic changes occurring in this system that may underlie the occurrence of pain-induced negative affect leading to misuse and abuse of opioid medications. Dissecting the allostatic neuronal changes occurring during pain is the most promising avenue to uncover novel targets for the development of safer pain medications. We will discuss this along with current and potential approaches to treat pain-induced negative affective states that lead to drug misuse. Moreover, this chapter will provide a discussion on potential avenues to reduce the abuse potential of new analgesic drugs and highlight a basis for future research and drug development based on recent advances in this field.
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Affiliation(s)
- Nicolas Massaly
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States; Washington University in St Louis, Pain Center, St. Louis, MO, United States; Washington University in St Louis, School of Medicine, St. Louis, MO, United States.
| | - Tamara Markovic
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States; Washington University in St Louis, Pain Center, St. Louis, MO, United States; Washington University in St Louis, School of Medicine, St. Louis, MO, United States
| | - Meaghan Creed
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States; Washington University in St Louis, Pain Center, St. Louis, MO, United States; Washington University in St Louis, School of Medicine, St. Louis, MO, United States; Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States; Department of Psychiatry, Washington University in St. Louis, St. Louis, MO, United States; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, United States
| | - Ream Al-Hasani
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States; Washington University in St Louis, Pain Center, St. Louis, MO, United States; Washington University in St Louis, School of Medicine, St. Louis, MO, United States; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, United States; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Catherine M Cahill
- Department of Psychiatry and Biobehavioural Sciences, University of California, Los Angeles, CA, United States; Shirley and Stefan Hatos Center for Neuropharmacology, University of California Los Angeles, Los Angeles, CA, United States; Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA, United States
| | - Jose A Moron
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, United States; Washington University in St Louis, Pain Center, St. Louis, MO, United States; Washington University in St Louis, School of Medicine, St. Louis, MO, United States; Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, United States; Department of Psychiatry, Washington University in St. Louis, St. Louis, MO, United States
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27
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Cahill CM, Holdridge SV, Liu S, Xue L, Magnussen C, Ong E, Grenier P, Sutherland A, Olmstead MC. Delta opioid receptor activation modulates affective pain and modality-specific pain hypersensitivity associated with chronic neuropathic pain. J Neurosci Res 2022; 100:129-148. [PMID: 32623788 PMCID: PMC8218601 DOI: 10.1002/jnr.24680] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/28/2020] [Accepted: 06/04/2020] [Indexed: 01/03/2023]
Abstract
Delta opioid receptor (DOR) agonists alleviate nociceptive behaviors in various chronic pain models, including neuropathic pain, while having minimal effect on sensory thresholds in the absence of injury. The mechanisms underlying nerve injury-induced enhancement of DOR function are unclear. We used a peripheral nerve injury (PNI) model of neuropathic pain to assess changes in the function and localization of DORs in mice and rats. Intrathecal administration of DOR agonists reversed mechanical allodynia and thermal hyperalgesia. The dose-dependent thermal antinociceptive effects of DOR agonists were shifted to the left in PNI rats. Administration of DOR agonists produced a conditioned place preference in PNI, but not in sham, animals, whereas the DOR antagonist naltrindole produced a place aversion in PNI, but not in sham, mice, suggesting the engagement of endogenous DOR activity in suppressing pain associated with the injury. GTPγS autoradiography revealed an increase in DOR function in the dorsal spinal cord, ipsilateral to PNI. Immunogold electron microscopy and in vivo fluorescent agonist assays were used to assess changes in the ultrastructural localization of DORs in the spinal dorsal horn. In shams, DORs were primarily localized within intracellular compartments. PNI significantly increased the cell surface expression of DORs within lamina IV-V dendritic profiles. Using neonatal capsaicin treatment, we identified that DOR agonist-induced thermal antinociception was mediated via receptors expressed on primary afferent sensory neurons but did not alter mechanical thresholds. These data reveal that the regulation of DORs following PNI and suggest the importance of endogenous activation of DORs in regulating chronic pain states.
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Affiliation(s)
- Catherine M. Cahill
- Dept of Psychiatry & Biobehavioral Sciences, Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, California, USA, 90095
| | - Sarah V. Holdridge
- Dept of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Steve Liu
- Dept of Psychiatry & Biobehavioral Sciences, Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, California, USA, 90095,Department of Psychology and Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Lihua Xue
- Dept of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Claire Magnussen
- Dept of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Edmund Ong
- Dept of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Patrick Grenier
- Dept of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Anne Sutherland
- Dept of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
| | - Mary C. Olmstead
- Department of Psychology and Centre for Neuroscience Studies, Queen’s University, Kingston, Ontario, Canada, K7L 3N6
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28
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Best KM, Mojena MM, Barr GA, Schmidt HD, Cohen AS. Endogenous Opioid Dynorphin Is a Potential Link between Traumatic Brain Injury, Chronic Pain, and Substance Use Disorder. J Neurotrauma 2022; 39:1-19. [PMID: 34751584 PMCID: PMC8978570 DOI: 10.1089/neu.2021.0063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Traumatic brain injury (TBI) is a serious public health problem associated with numerous physical and neuropsychiatric comorbidities. Chronic pain is prevalent and interferes with post-injury functioning and quality of life, whereas substance use disorder (SUD) is the third most common neuropsychiatric diagnosis after TBI. Neither of these conditions has a clear mechanistic explanation based on the known pathophysiology of TBI. Dynorphin is an endogenous opioid neuropeptide that is significantly dysregulated after TBI. Both dynorphin and its primary receptor, the ĸ-opioid receptor (KOR), are implicated in the neuropathology of chronic pain and SUD. Here, we review the known roles of dynorphin and KORs in chronic pain and SUDs. We synthesize this information with our current understanding of TBI and highlight potential mechanistic parallels between and across conditions that suggest a role for dynorphin in long-term sequelae after TBI. In pain studies, dynorphin/KOR activation has either antinociceptive or pro-nociceptive effects, and there are similarities between the signaling pathways influenced by dynorphin and those underlying development of chronic pain. Moreover, the dynorphin/KOR system is considered a key regulator of the negative affective state that characterizes drug withdrawal and protracted abstinence in SUD, and molecular and neurochemical changes observed during the development of SUD are mirrored by the pathophysiology of TBI. We conclude by proposing hypotheses and directions for future research aimed at elucidating the potential role of dynorphin/KOR in chronic pain and/or SUD after TBI.
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Affiliation(s)
- Kaitlin M. Best
- Department of Nursing and Clinical Care Services, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Marissa M. Mojena
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Gordon A. Barr
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Psychology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Heath D. Schmidt
- Department of Biobehavioral Health Sciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Akiva S. Cohen
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Address correspondence to: Akiva S. Cohen, PhD, Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine, University of Pennsylvania, 3615 Civic Center Boulevard, Room 816-I, Philadelphia, PA 19104, USA
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29
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Aldrich JV, McLaughlin JP. Peptide Kappa Opioid Receptor Ligands and Their Potential for Drug Development. Handb Exp Pharmacol 2022; 271:197-220. [PMID: 34463847 DOI: 10.1007/164_2021_519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ligands for kappa opioid receptors (KOR) have potential uses as non-addictive analgesics and for the treatment of pruritus, mood disorders, and substance abuse. These areas continue to have major unmet medical needs. Significant advances have been made in recent years in the preclinical development of novel opioid peptides, notably ones with structural features that inherently impart stability to proteases. Following a brief discussion of the potential therapeutic applications of KOR agonists and antagonists, this review focuses on two series of novel opioid peptides, all-D-amino acid tetrapeptides as peripherally selective KOR agonists for the treatment of pain and pruritus without centrally mediated side effects, and macrocyclic tetrapeptides based on CJ-15,208 that can exhibit different opioid profiles with potential applications such as analgesics and treatments for substance abuse.
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Affiliation(s)
- Jane V Aldrich
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, USA.
| | - Jay P McLaughlin
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA.
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30
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Agonist-promoted kappa opioid receptor (KOR) phosphorylation has behavioral endpoint-dependent and sex-specific effects. Neuropharmacology 2022; 202:108860. [PMID: 34736959 PMCID: PMC9122667 DOI: 10.1016/j.neuropharm.2021.108860] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 10/27/2021] [Accepted: 10/29/2021] [Indexed: 02/07/2023]
Abstract
We reported previously that the selective agonist U50,488H promoted phosphorylation of the mouse kappa opioid receptor (mKOR) in vitro at four residues in the C-terminal domain. In this study, we generated a mutant mouse line in which all the four residues were mutated to Ala (K4A) to examine the in vivo functional significance of agonist-induced KOR phosphorylation. U50,488H promoted KOR phosphorylation in brains of the wildtype (WT), but not K4A, male and female mice. Autoradiography of [3H] 69,593 binding to KOR in brain sections showed that WT and K4A mice had similar KOR distribution and expression levels in brain regions without sex differences. In K4A mice, U50,488H inhibited compound 48/80-induced scratching and attenuated novelty-induced hyperlocomotion to similar extents as in WT mice without sex differences. Interestingly, repeated pretreatment with U50,488H (80 mg/kg, s.c.) resulted in profound tolerance to the anti-scratch effects of U50,488H (5 mg/kg, s.c.) in WT mice of both sexes and female K4A mice, while in male K4A mice tolerance was attenuated. Moreover, U50,488H (2 mg/kg) induced conditioned place aversion (CPA) in WT mice of both sexes and male K4A mice, but not in female K4A mice. In contrast, U50,488H (5 mg/kg) caused CPA in male, but not female, mice, regardless of genotype. Thus, agonist-promoted KOR phosphorylation plays important roles in U50,488H-induced tolerance and CPA in a sex-dependent manner, without affecting acute U50,488H-induced anti-pruritic and hypo-locomotor effects. These results are the first to demonstrate sex differences in the effects of GPCR phosphorylation on the GPCR-mediated behaviors.
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31
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Taylor AM, Chadwick CI, Mehrabani S, Hrncir H, Arnold AP, Evans CJ. Sex differences in kappa opioid receptor antinociception is influenced by the number of X chromosomes in mouse. J Neurosci Res 2022; 100:183-190. [PMID: 32731302 PMCID: PMC8452150 DOI: 10.1002/jnr.24704] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 01/03/2023]
Abstract
Kappa opioid receptor (KOR) agonists produce robust analgesia with minimal abuse liability and are considered promising pharmacological agents to manage chronic pain and itch. The KOR system is also notable for robust differences between the sexes, with females exhibiting lower analgesic response than males. Sexually dimorphic traits can be due to either the influence of gonadal hormones during development or adulthood, or due to the complement of genes expressed on the X or Y chromosome. Previous studies examining sex differences in KOR antinociception have relied on surgical or pharmacological manipulation of the gonads to determine whether sex hormones influence KOR function. While there are conflicting reports whether gonadal hormones influence KOR function, no study has examined these effects in context with sex chromosomes. Here, we use two genetic mouse models, the four core genotypes and XY*, to isolate the chromosomal and hormonal contributions to sex differences in KOR analgesia. Mice were treated with systemic KOR agonist (U50,488H) and thermal analgesia measured in the tail withdrawal assay. We found that KOR antinociception was influenced predominantly by the number of the X chromosomes. These data suggest that the dose and/or parental imprint on X gene(s) contribute significantly to the sexually dimorphism in KOR analgesia.
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Affiliation(s)
- Anna M.W. Taylor
- Department of Pharmacology, University of Alberta, Edmonton, Canada,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Caylin I. Chadwick
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Sadaf Mehrabani
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, USA
| | - Haley Hrncir
- Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, USA
| | - Arthur P. Arnold
- Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, USA
| | - Christopher J. Evans
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, USA
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Ko MC, Husbands SM. Pleiotropic Effects of Kappa Opioid Receptor-Related Ligands in Non-human Primates. Handb Exp Pharmacol 2022; 271:435-452. [PMID: 33274403 PMCID: PMC8175454 DOI: 10.1007/164_2020_419] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The kappa opioid receptor (KOR)-related ligands have been demonstrated in preclinical studies for several therapeutic potentials. This chapter highlights (1) how non-human primates (NHP) studies facilitate the research and development of ligands targeting the KOR, (2) effects of the endogenous opioid peptide, dynorphin A-(1-17), and its analogs in NHP, and (3) pleiotropic effects and therapeutic applications of KOR-related ligands. In particular, synthetic ligands targeting the KOR have been extensively studied in NHP in three therapeutic areas, i.e., the treatment for itch, pain, and substance use disorders. As the KORs are widely expressed in the peripheral and central nervous systems, pleiotropic effects of KOR-related ligands, such as discriminative stimulus effects, neuroendocrine effects (e.g., prolactin release and stimulation of hypothalamic-pituitary-adrenal axis), and diuresis, in NHP are discussed. Centrally acting KOR agonists are known to produce adverse effects including dysphoria, hallucination, and sedation. Nonetheless, with strategic advances in medicinal chemistry, three classes of KOR-related agonists, i.e., peripherally restricted KOR agonists, mixed KOR/mu opioid receptor partial agonists, and G protein-biased KOR agonists, warrant additional NHP studies to improve our understanding of their functional efficacy, selectivity, and tolerability. Pharmacological studies in NHP which carry high translational significance will facilitate future development of KOR-based medications.
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Affiliation(s)
- Mei-Chuan Ko
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
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Abstract
The opioid peptides and their receptors have been linked to multiple key biological processes in the nervous system. Here we review the functions of the kappa opioid receptor (KOR) and its endogenous agonists dynorphins (Goldstein A, Tachibana S, Lowney LI, Hunkapiller M, Hood L, Proc Natl Acad Sci U S A 76:6666-6670, 1979) in modulating itch and pain (nociception). Specifically, we discuss their roles relative to recent findings that tell us more about the cells and circuits which are impacted by this opioid and its receptor and present reanalysis of single-cell sequencing data showing the expression profiles of these molecules. Since the KOR is relatively specifically activated by peptides derived from the prodynorphin gene and other opioid peptides that show lower affinities, this will be the only interactions we consider (Chavkin C, Goldstein A, Nature 291:591-593, 1981; Chavkin C, James IF, Goldstein A, Science 215:413-415, 1982), although it was noted that at higher doses peptides other than dynorphins might stimulate KOR (Lai J, Luo MC, Chen Q, Ma S, Gardell LR, Ossipov MH, Porreca F, Nat Neurosci 9:1534-1540, 2006). This review has been organized based on anatomy with each section describing the effect of the kappa opioid system in a specific location but let us not forget that most of these circuits are interconnected and are therefore interdependent.
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Affiliation(s)
- Pang-Yen Tseng
- Molecular Genetics Section, National Institute of Dental and Craniofacial Research/NIH, Bethesda, MD, USA
| | - Mark A Hoon
- Molecular Genetics Section, National Institute of Dental and Craniofacial Research/NIH, Bethesda, MD, USA.
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The Role of Mesostriatal Dopamine System and Corticostriatal Glutamatergic Transmission in Chronic Pain. Brain Sci 2021; 11:brainsci11101311. [PMID: 34679376 PMCID: PMC8533867 DOI: 10.3390/brainsci11101311] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 12/21/2022] Open
Abstract
There is increasing recognition of the involvement of the nigrostriatal and mesolimbic dopamine systems in the modulation of chronic pain. The first part of the present article reviews the evidence indicating that dopamine exerts analgesic effects during persistent pain by stimulating the D2 receptors in the dorsal striatum and nucleus accumbens (NAc). Thereby, dopamine inhibits striatal output via the D2 receptor-expressing medium spiny neurons (D2-MSN). Dopaminergic neurotransmission in the mesostriatal pathways is hampered in chronic pain states and this alteration maintains and exacerbates pain. The second part of this article focuses on the glutamatergic inputs from the medial prefrontal cortex to the NAc, their activity changes in chronic pain, and their role in pain modulation. Finally, interactions between dopaminergic and glutamatergic inputs to the D2-MSN are considered in the context of persistent pain. Studies using novel techniques indicate that pain is regulated oppositely by two independent dopaminergic circuits linking separate parts of the ventral tegmental area and of the NAc, which also interact with distinct regions of the medial prefrontal cortex.
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Cameron CM, Nieto S, Bosler L, Wong M, Bishop I, Mooney L, Cahill CM. Mechanisms Underlying the Anti-Suicidal Treatment Potential of Buprenorphine. ADVANCES IN DRUG AND ALCOHOL RESEARCH 2021; 1. [PMID: 35265942 PMCID: PMC8903193 DOI: 10.3389/adar.2021.10009] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Death by suicide is a global epidemic with over 800 K suicidal deaths worlwide in 2012. Suicide is the 10th leading cause of death among Americans and more than 44 K people died by suicide in 2019 in the United States. Patients with chronic pain, including, but not limited to, those with substance use disorders, are particularly vulnerable. Chronic pain patients have twice the risk of death by suicide compared to those without pain, and 50% of chronic pain patients report that they have considered suicide at some point due to their pain. The kappa opioid system is implicated in negative mood states including dysphoria, depression, and anxiety, and recent evidence shows that chronic pain increases the function of this system in limbic brain regions important for affect and motivation. Additionally, dynorphin, the endogenous ligand that activates the kappa opioid receptor is increased in the caudate putamen of human suicide victims. A potential treatment for reducing suicidal ideation and suicidal attempts is buprenorphine. Buprenorphine, a partial mu opioid agonist with kappa opioid antagonist properties, reduced suicidal ideation in chronic pain patients with and without an opioid use disorder. This review will highlight the clinical and preclinical evidence to support the use of buprenorphine in mitigating pain-induced negative affective states and suicidal thoughts, where these effects are at least partially mediated via its kappa antagonist properties.
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Affiliation(s)
- Courtney M. Cameron
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, United States
- Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA, United States
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, United States
- David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Steven Nieto
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Lucienne Bosler
- Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Megan Wong
- Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Isabel Bishop
- Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Larissa Mooney
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, United States
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, United States
- David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Catherine M. Cahill
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, United States
- Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, Los Angeles, CA, United States
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, United States
- David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Correspondence: Catherine M. Cahill,
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Gregus AM, Levine IS, Eddinger KA, Yaksh TL, Buczynski MW. Sex differences in neuroimmune and glial mechanisms of pain. Pain 2021; 162:2186-2200. [PMID: 34256379 PMCID: PMC8277970 DOI: 10.1097/j.pain.0000000000002215] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 12/03/2020] [Indexed: 02/07/2023]
Abstract
ABSTRACT Pain is the primary motivation for seeking medical care. Although pain may subside as inflammation resolves or an injury heals, it is increasingly evident that persistency of the pain state can occur with significant regularity. Chronic pain requires aggressive management to minimize its physiological consequences and diminish its impact on quality of life. Although opioids commonly are prescribed for intractable pain, concerns regarding reduced efficacy, as well as risks of tolerance and dependence, misuse, diversion, and overdose mortality rates limit their utility. Advances in development of nonopioid interventions hinge on our appreciation of underlying mechanisms of pain hypersensitivity. For instance, the contributory role of immunity and the associated presence of autoimmune syndromes has become of particular interest. Males and females exhibit fundamental differences in innate and adaptive immune responses, some of which are present throughout life, whereas others manifest with reproductive maturation. In general, the incidence of chronic pain conditions, particularly those with likely autoimmune covariates, is significantly higher in women. Accordingly, evidence is now accruing in support of neuroimmune interactions driving sex differences in the development and maintenance of pain hypersensitivity and chronicity. This review highlights known sexual dimorphisms of neuroimmune signaling in pain states modeled in rodents, which may yield potential high-value sex-specific targets to inform future analgesic drug discovery efforts.
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Affiliation(s)
- Ann M Gregus
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, VA, United States
| | - Ian S Levine
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, VA, United States
| | | | - Tony L Yaksh
- Departments of Anesthesiology and
- Pharmacology, University of California San Diego, La Jolla, CA, United States
| | - Matthew W Buczynski
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, VA, United States
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Rullo L, Posa L, Caputi FF, Stamatakos S, Formaggio F, Caprini M, Liguori R, Candeletti S, Romualdi P. Nociceptive behavior and central neuropeptidergic dysregulations in male and female mice of a Fabry disease animal model. Brain Res Bull 2021; 175:158-167. [PMID: 34339779 DOI: 10.1016/j.brainresbull.2021.07.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/16/2021] [Accepted: 07/26/2021] [Indexed: 01/22/2023]
Abstract
Fabry disease (FD) is an X-linked inherited disorder characterized by glycosphingolipid accumulation due to deficiency of α-galactosidase A (α-Gal A) enzyme. Chronic pain and mood disorders frequently coexist in FD clinical setting, however underlying pathophysiologic mechanisms are still unclear. Here we investigated the mechanical and thermal sensitivity in α-Gal A (-/0) hemizygous male and the α-Gal A (-/-) homozygous female mice. We also characterized the gene expression of dynorphinergic, nociceptinergic and CRFergic systems, known to be involved in pain control and mood disorders, in the prefrontal cortex, amygdala and thalamus of α-Gal A (-/0) hemizygous male and the α-Gal A (-/-) homozygous female mice. Moreover, KOP receptor protein levels were evaluated in the same areas. Fabry knock-out male, but not female, mice displayed a decreased pain threshold in both mechanical and thermal tests compared to their wild type littermates. In the amygdala and prefrontal cortex, we observed a decrease of pDYN mRNA levels in males, whereas an increase was assessed in females, thus suggesting sex-related dysregulation of stress coping and pain mechanisms. Elevated mRNA levels for pDYN/KOP and CRF/CRFR1 systems were observed in male and female thalamus, a critical crossroad for both painful signals and cognitive/emotional processes. KOP receptor protein level changes assessed in the investigated areas, appeared mostly in agreement with KOP gene expression alterations. Our data suggest that α-Gal A enzyme deficiency in male and female mice is associated with distinct neuropeptide gene and protein expression dysregulations of investigated systems, possibly related to the neuroplasticity underlying the neurological features of FD.
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Affiliation(s)
- Laura Rullo
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy
| | - Luca Posa
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy; Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Francesca Felicia Caputi
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy
| | - Serena Stamatakos
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy
| | - Francesco Formaggio
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy
| | - Marco Caprini
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy
| | - Rocco Liguori
- IRCCS Institute of Neurological Sciences, Bologna, Italy; Dept. of Biomedical and Neuromotor Sciences (DiBiNeM), Alma Mater Studiorum - University of Bologna, Via Altura 3, Bologna, 40139, Italy
| | - Sanzio Candeletti
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy
| | - Patrizia Romualdi
- Dept. of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum - University of Bologna, Via Irnerio 48, Bologna, 40126, Italy.
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Tavares I, Costa-Pereira JT, Martins I. Monoaminergic and Opioidergic Modulation of Brainstem Circuits: New Insights Into the Clinical Challenges of Pain Treatment? FRONTIERS IN PAIN RESEARCH 2021; 2:696515. [PMID: 35295506 PMCID: PMC8915776 DOI: 10.3389/fpain.2021.696515] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 06/08/2021] [Indexed: 12/22/2022] Open
Abstract
The treatment of neuropathic pain remains a clinical challenge. Analgesic drugs and antidepressants are frequently ineffective, and opioids may induce side effects, including hyperalgesia. Recent results on brainstem pain modulatory circuits may explain those clinical challenges. The dual action of noradrenergic (NA) modulation was demonstrated in animal models of neuropathic pain. Besides the well-established antinociception due to spinal effects, the NA system may induce pronociception by directly acting on brainstem pain modulatory circuits, namely, at the locus coeruleus (LC) and medullary dorsal reticular nucleus (DRt). The serotoninergic system also has a dual action depending on the targeted spinal receptor, with an exacerbated activity of the excitatory 5-hydroxytryptamine 3 (5-HT3) receptors in neuropathic pain models. Opioids are involved in the modulation of descending modulatory circuits. During neuropathic pain, the opioidergic modulation of brainstem pain control areas is altered, with the release of enhanced local opioids along with reduced expression and desensitization of μ-opioid receptors (MOR). In the DRt, the installation of neuropathic pain increases the levels of enkephalins (ENKs) and induces desensitization of MOR, which may enhance descending facilitation (DF) from the DRt and impact the efficacy of exogenous opioids. On the whole, the data discussed in this review indicate the high plasticity of brainstem pain control circuits involving monoaminergic and opioidergic control. The data from studies of these neurochemical systems in neuropathic models indicate the importance of designing drugs that target multiple neurochemical systems, namely, maximizing the antinociceptive effects of antidepressants that inhibit the reuptake of serotonin and noradrenaline and preventing desensitization and tolerance of MOR at the brainstem.
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Affiliation(s)
- Isaura Tavares
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal
- *Correspondence: Isaura Tavares
| | - José Tiago Costa-Pereira
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal
- Faculty of Nutrition and Food Science, University of Porto, Porto, Portugal
| | - Isabel Martins
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal
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Kibaly C, Alderete JA, Liu SH, Nasef HS, Law PY, Evans CJ, Cahill CM. Oxycodone in the Opioid Epidemic: High 'Liking', 'Wanting', and Abuse Liability. Cell Mol Neurobiol 2021; 41:899-926. [PMID: 33245509 PMCID: PMC8155122 DOI: 10.1007/s10571-020-01013-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/17/2020] [Indexed: 12/13/2022]
Abstract
It is estimated that nearly a third of people who abuse drugs started with prescription opioid medicines. Approximately, 11.5 million Americans used prescription drugs recreationally in 2016, and in 2018, 46,802 Americans died as the result of an opioid overdose, including prescription opioids, heroin, and illicitly manufactured fentanyl (National Institutes on Drug Abuse (2020) Opioid Overdose Crisis. https://www.drugabuse.gov/drugs-abuse/opioids/opioid-overdose-crisis . Accessed 06 June 2020). Yet physicians will continue to prescribe oral opioids for moderate-to-severe pain in the absence of alternative therapeutics, underscoring the importance in understanding how drug choice can influence detrimental outcomes. One of the opioid prescription medications that led to this crisis is oxycodone, where misuse of this drug has been rampant. Being one of the most highly prescribed opioid medications for treating moderate-to-severe pain as reflected in the skyrocketed increase in retail sales of 866% between 1997 and 2007, oxycodone was initially suggested to be less addictive than morphine. The false-claimed non-addictive formulation of oxycodone, OxyContin, further contributed to the opioid crisis. Abuse was often carried out by crushing the pills for immediate burst release, typically by nasal insufflation, or by liquefying the pills for intravenous injection. Here, we review oxycodone pharmacology and abuse liability as well as present the hypothesis that oxycodone may exhibit a unique pharmacology that contributes to its high likability and abuse susceptibility. We will discuss various mechanisms that likely contribute to the high abuse rate of oxycodone including clinical drug likability, pharmacokinetics, pharmacodynamics, differences in its actions within mesolimbic reward circuity compared to other opioids, and the possibility of differential molecular and cellular receptor interactions that contribute to its selective effects. We will also discuss marketing strategies and drug difference that likely contributes to the oxycodone opioid use disorders and addiction.
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Affiliation(s)
- Cherkaouia Kibaly
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA.
| | - Jacob A Alderete
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA
| | - Steven H Liu
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA
| | - Hazem S Nasef
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA
| | - Ping-Yee Law
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA
| | - Christopher J Evans
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA
| | - Catherine M Cahill
- Department of Psychiatry and Biobehavioral Sciences, Jane & Terry Semel Institute for Neuroscience and Human Behavior, Shirley and Stefan Hatos Center for Neuropharmacology, University of California, Los Angeles, CA, USA.
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40
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Abstract
This paper is the forty-second consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2019 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY, 11367, United States.
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41
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Kappa opioid receptor modulation of endometriosis pain in mice. Neuropharmacology 2021; 195:108677. [PMID: 34153313 DOI: 10.1016/j.neuropharm.2021.108677] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 06/10/2021] [Accepted: 06/13/2021] [Indexed: 12/30/2022]
Abstract
The kappa opioid receptor is a constituent of the endogenous opioid analgesia system widely expressed in somatosensory nervous pathways and also in endometrial tissues. This work investigates the possible involvement of kappa opioid receptor on the nociceptive, behavioral and histopathological manifestations of endometriosis in a murine model. Female mice receiving endometrial implants develop a persistent mechanical hypersensitivity in the pelvic area that is stronger during the estrus phase of the estrous cycle. The kappa opioid receptor agonist U50,488H produces a dose-dependent relief of this mechanical hypersensitivity, regardless of the cycle phase. Repeated exposure to a low dose of U50,488H (1 mg/kg/day s.c. for one month) provides sustained relief of mechanical hypersensitivity, without tolerance development or sedative side effects. Interestingly, this treatment also inhibits a decreased rearing behavior associated with spontaneous pain or discomfort in endometriosis mice. This KOR-mediated pain relief does not prevent the anxiety-like behavior or the cognitive impairment exhibited by endometriosis mice, and the growth of endometriotic cysts is also unaltered. These data provide evidence of strong pain-relieving properties of kappa opioid receptor stimulation in female mice with endometriosis pain. The persistence of affective and cognitive manifestations suggests that these comorbidities are independent of pelvic pain and simultaneous treatment of these comorbidities may be necessary for successful management of endometriosis.
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42
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Costanza A, Chytas V, Piguet V, Luthy C, Mazzola V, Bondolfi G, Cedraschi C. Meaning in Life Among Patients With Chronic Pain and Suicidal Ideation: Mixed Methods Study. JMIR Form Res 2021; 5:e29365. [PMID: 34003136 PMCID: PMC8214181 DOI: 10.2196/29365] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/06/2021] [Accepted: 05/16/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Patients with chronic pain have elevated risk of suicidal ideation and behavior, including suicide attempts and completed suicides. In most studies, associations between chronic pain and suicidal ideation/suicidal behavior are robust even after adjusting for the effect of sociodemographics and psychiatric comorbidity. However, to refine the risk profile of these patients, further exploration of other possible risk and protective factors is necessary. OBJECTIVE There is a common clinical observation that experiencing chronic pain often requires a revision of life goals and expectations, and hence, it impacts the existential domain including one's perception of the meaning in life (MiL). This study aimed to characterize the main domains that constitute the personal MiL, including the "presence of" and "search for" constructs, in a group of patients with chronic pain and suicidal ideation. METHODS Seventy participants were enlisted by ongoing recruitment through a larger project anchored in daily clinical practice at the Multidisciplinary Pain Center of the Geneva University Hospitals. It was an observational mixed method study. Data were recorded through both validated quantitative questionnaires and qualitative open-ended questions. RESULTS The total sample consisted of 70 patients. Responses to questionnaires showed a depressive episode in 68 (97%) patients and anxious disorders in 25 (36%) patients. With a score threshold for positive MiL of 24, the mean score for the "presence of" construct was 20.13 (SD 8.23), and 63% (44/70) of respondents had a score <24. The mean score for the "search for" construct was lower at 18.14 (SD 8.64), and 70% (49/70) of respondents had a score <24. The "presence of" and "search for" constructs were significantly positively correlated (R=0.402; P=.001). An open question addressed the "presence of" construct by inviting the respondents to cite domains they consider as providing meaning in their life at the present time. All patients responded to this question, citing one or more domains. The three main dimensions that emerged from content analysis of this qualitative section were as follows: the domain of relationships, the domain of personal activities, and pain and its consequences on MiL. CONCLUSIONS The study results provide insights into patients with chronic pain and suicidal ideation, including the domains that provide them with meaning in their lives and the impact of pain on these domains with regard to suicidal ideation. The main clinical implications concern both prevention and supportive/psychotherapeutic interventions. They are based on a narrative approach aiming to explore with the patients the content of their suffering and the MiL domains that they could identify to mitigate it, in order to restructure/reinforce these domains and thus possibly reduce suicidal ideation. Specifically, a focus on maintaining the domains of interpersonal relationships and personal activities can allow patients to ultimately escape the biopsychosocial vicious cycle of chronic pain-induced deep moral suffering.
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Affiliation(s)
- Alessandra Costanza
- Department of Psychiatry, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vasileios Chytas
- Division of Clinical Pharmacology & Toxicology, Multidisciplinary Pain Centre, Geneva University Hospitals, Geneva, Switzerland.,Department of Psychiatry, Service of Liaison Psychiatry and Crisis Intervention, Geneva University Hospitals, Geneva, Switzerland
| | - Valérie Piguet
- Division of Clinical Pharmacology & Toxicology, Multidisciplinary Pain Centre, Geneva University Hospitals, Geneva, Switzerland
| | - Christophe Luthy
- Division of General Medical Rehabilitation, Geneva University Hospitals, Geneva, Switzerland.,Department of Geriatrics and Rehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Viridiana Mazzola
- Department of Psychiatry, Service of Liaison Psychiatry and Crisis Intervention, Geneva University Hospitals, Geneva, Switzerland
| | - Guido Bondolfi
- Department of Psychiatry, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Department of Psychiatry, Service of Liaison Psychiatry and Crisis Intervention, Geneva University Hospitals, Geneva, Switzerland
| | - Christine Cedraschi
- Division of Clinical Pharmacology & Toxicology, Multidisciplinary Pain Centre, Geneva University Hospitals, Geneva, Switzerland.,Division of General Medical Rehabilitation, Geneva University Hospitals, Geneva, Switzerland.,Department of Geriatrics and Rehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Uncovering the analgesic effects of a pH-dependent mu-opioid receptor agonist using a model of nonevoked ongoing pain. Pain 2021; 161:2798-2804. [PMID: 32639370 DOI: 10.1097/j.pain.0000000000001968] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Currently, opioids targeting mu-opioid receptors are the most potent drugs for acute and cancer pain. However, opioids produce adverse side effects such as constipation, respiratory depression, or addiction potential. We recently developed (±)-N-(3-fluoro-1-phenethylpiperidine-4-yl)-N-phenyl propionamide (NFEPP), a compound that does not evoke central or intestinal side effects due to its selective activation of mu-opioid receptors at low pH in peripheral injured tissues. Although we demonstrated that NFEPP effectively abolishes injury-induced pain, hyperalgesia, and allodynia in rodents, the efficacy of NFEPP in nonevoked ongoing pain remains to be established. Here, we examined reward, locomotor activity, and defecation in rats with complete Freund's adjuvant-induced paw inflammation to compare fentanyl's and NFEPP's potentials to induce side effects and to inhibit spontaneous pain. We demonstrate that low, but not higher, doses of NFEPP produce conditioned place preference but not constipation or motor disturbance, in contrast to fentanyl. Using a peripherally restricted antagonist, we provide evidence that NFEPP-induced place preference is mediated by peripheral opioid receptors. Our results indicate that a low dose of NFEPP produces reward by abolishing spontaneous inflammatory pain.
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Marchette RCN, Gregory-Flores A, Tunstall BJ, Carlson ER, Jackson SN, Sulima A, Rice KC, Koob GF, Vendruscolo LF. κ-Opioid receptor antagonism reverses heroin withdrawal-induced hyperalgesia in male and female rats. Neurobiol Stress 2021; 14:100325. [PMID: 33997152 PMCID: PMC8095052 DOI: 10.1016/j.ynstr.2021.100325] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 03/18/2021] [Accepted: 04/06/2021] [Indexed: 10/29/2022] Open
Abstract
Although opioids are potent analgesics, a consequence of chronic opioid use is hyperalgesia during withdrawal, which may contribute to opioid misuse. Dynorphin, the endogenous ligand of κ-opioid receptors (KORs), is upregulated in opioid-dependent rats and in animal models of chronic pain. However, the role of KORs in opioid withdrawal-induced hyperalgesia remains to be determined. We hypothesized that KOR antagonism would reverse opioid withdrawal-induced hyperalgesia in opioid-dependent rats. Male and female Wistar rats received daily injections of heroin (2-6 mg/kg, SC) and were tested for mechanical sensitivity in the electronic von Frey test 4-6 h into withdrawal. Female rats required significantly more heroin than male rats to reach comparable levels of both heroin-induced analgesia and hyperalgesia (6 mg/kg vs. 2 mg/kg). Once hyperalgesia was established, we tested the effects of the KOR antagonists nor-binaltorphimine (norBNI; 30 mg/kg, SC) and 5'-guanidinonaltrindole (5'GNTI; 30 mg/kg, SC). When the animals continued to receive their daily heroin treatment (or saline treatment in the repeated saline group) five times per week throughout the experiment, both KOR antagonists reversed heroin withdrawal-induced hyperalgesia. The anti-hyperalgesia effect of norBNI was more prolonged in males than in females (14 days vs. 7 days), whereas 5'GNTI had more prolonged effects in females than in males (14 days vs. 4 days). The behavioral effects of 5'GNTI coincided with higher 5'GNTI levels in the brain than in plasma when measured at 24 h, whereas 5'GNTI did not reverse hyperalgesia at 30 min posttreatment when 5'GNTI levels were higher in plasma than in the brain. Finally, we tested the effects of 5'GNTI on naloxone-induced and spontaneous signs of opioid withdrawal and found no effect in either male or female rats. These findings indicate a functional role for KORs in heroin withdrawal-induced hyperalgesia that is observed in rats of both sexes.
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Affiliation(s)
- Renata C N Marchette
- Neurobiology of Addiction Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Adriana Gregory-Flores
- Neurobiology of Addiction Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Brendan J Tunstall
- Department of Pharmacology, Addiction Science, and Toxicology, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Erika R Carlson
- Neurobiology of Addiction Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Shelley N Jackson
- Structural Biology Core, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Agnieszka Sulima
- Drug Design and Synthesis Section, National Institute on Drug Abuse, Intramural Research Program, Bethesda, MD, USA
| | - Kenner C Rice
- Drug Design and Synthesis Section, National Institute on Drug Abuse, Intramural Research Program, Bethesda, MD, USA
| | - George F Koob
- Neurobiology of Addiction Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Leandro F Vendruscolo
- Neurobiology of Addiction Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
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45
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Lee GJ, Kim SA, Kim YJ, Oh SB. Naloxone-induced analgesia mediated by central kappa opioid system in chronic inflammatory pain. Brain Res 2021; 1762:147445. [PMID: 33766518 DOI: 10.1016/j.brainres.2021.147445] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 03/07/2021] [Accepted: 03/17/2021] [Indexed: 12/22/2022]
Abstract
Opioids, which are widely used for the treatment of chronic pain, have an analgesic effect by mainly activating mu-opioid receptor (MOR). Paradoxically, a high dose of naloxone, non-selective opioid receptor antagonist, is also known to induce analgesia, but the underlying mechanism remains unclear. Since kappa-opioid receptor (KOR) and dynorphin (KOR ligand) have been implicated in the naloxone-induced analgesia, we aimed to elucidate its mechanism by focusing on the kappa-opioid system in the brain under inflammatory pain condition. Systemic administration of naloxone (10 mg/kg, i.p.) decreased spontaneous pain behaviors only in complete Freund's adjuvant (CFA)-induced chronic inflammatory pain model but not in the formalin-induced acute pain model. Immunohistochemistry analysis in the CFA model revealed both a significant decrease in MOR expression and an increase in prodynorphin density in the central nucleus of theamygdala (CeA) and nucleus accumbens (NAc) but not in other brain areas. Systemic administration of KOR antagonist (norbinaltorphimine, nor-BNI 10 mg/kg) also decreased spontaneous pain behaviors in the CFA model. Furthermore, microinjection of both naloxone and nor-BNI into NAc and CeA significantly reduced spontaneous chronic pain behavior. Taken together, our results suggest that naloxone-induced analgesia may be mediated by blocking facilitated kappa-opioid systems in the NAc and CeA.
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Affiliation(s)
- Grace J Lee
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - Shin Ae Kim
- Dental Research Institute and Department of Neurobiology & Physiology, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Yea Jin Kim
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - Seog Bae Oh
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea; Dental Research Institute and Department of Neurobiology & Physiology, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
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46
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Effects of inflammatory pain on CB1 receptor in the midbrain periaqueductal gray. Pain Rep 2021; 6:e897. [PMID: 33693301 PMCID: PMC7939232 DOI: 10.1097/pr9.0000000000000897] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/10/2020] [Accepted: 12/25/2020] [Indexed: 11/26/2022] Open
Abstract
Western blot and GTPγS analyses reveal inflammatory pain–induced adaptations in the midbrain periaqueductal gray, which is critically involved in descending pain modulation. Pain upregulates the expression of the CB1 receptor and increases G-protein coupling in the periaqueductal gray. Introduction: The periaqueductal gray (PAG) mediates the antinociceptive properties of analgesics, including opioids and cannabinoids. Administration of either opioids or cannabinoids into the PAG induces antinociception. However, most studies characterizing the antinociceptive properties of cannabinoids in the PAG have been conducted in naive animals. Few studies have reported on the role of CB1 receptors in the PAG during conditions which would prompt the administration of analgesics, namely, during pain states. Objectives: To examine inflammatory pain-induced changes in CB1 receptor expression and function in the midbrain periaqueductal gray. Methods: In this study, we used the Complete Freund Adjuvant model to characterize CB1 receptor expression and G-protein coupling during persistent inflammatory pain. Results: Inflammatory pain induced an upregulation in the expression of synaptic CB1 receptors in the PAG. Despite this pain-induced change in CB1 expression, there was no corresponding upregulation of CB1 mRNA after the induction of inflammatory pain, suggesting a pain-induced recruitment of CB1 receptors to the synaptic sites within PAG neurons or increased coupling efficiency between the receptor and effector systems. Inflammatory pain also enhanced ventrolateral PAG CB1 receptor activity, as there was an increase in CP55,940-stimulated G-protein activation compared with pain-naïve control animals. Conclusion: These findings complement a growing body of evidence which demonstrate pain-induced changes in brain regions that are responsible for both the analgesic and rewarding properties of analgesic pharmacotherapies. Because much of our understanding of the pharmacology of cannabinoids is based on studies which use largely pain-naïve male animals, this work fills in important gaps in the knowledge base by incorporating pain-induced adaptations and cannabinoid pharmacology in females.
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47
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Hein M, Ji G, Tidwell D, D'Souza P, Kiritoshi T, Yakhnitsa V, Navratilova E, Porreca F, Neugebauer V. Kappa opioid receptor activation in the amygdala disinhibits CRF neurons to generate pain-like behaviors. Neuropharmacology 2021; 185:108456. [PMID: 33444637 PMCID: PMC7887082 DOI: 10.1016/j.neuropharm.2021.108456] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/01/2021] [Accepted: 01/05/2021] [Indexed: 12/15/2022]
Abstract
Recent evidence suggests that kappa opioid receptors (KOR) in limbic brain regions such as the amygdala contribute to pain conditions, but underlying mechanisms remain to be determined. The amygdala is an important player in averse-affective aspects of pain and pain modulation. The central nucleus (CeA) serves output functions through projection neurons that include corticotropin releasing factor (CRF) expressing neurons. The CeA is also rich in KOR. Here we tested the novel hypothesis that KOR activation in the CeA generates pain-like behaviors through a mechanism that involves inhibition of synaptic inhibition (disinhibition) of CRF neurons. Intra-CeA administration of a KOR agonist (U-69,593) increased vocalizations of naïve rats to noxious stimuli, and induced anxiety-like behaviors in the open field test (OFT) and avoidance in the conditioned place preference test, without affecting mechanosensory thresholds. Optogenetic silencing of CeA-CRF neurons blocked the facilitatory effects of systemically applied U-69,593 in naïve rats. Patch-clamp recordings of CRF neurons in rat brain slices found that U-69,593 decreased feedforward inhibitory transmission evoked by optogenetic stimulation of parabrachial afferents, but had no effect on monosynaptic excitatory transmission. U-69,593 decreased frequency, but not amplitude, of inhibitory synaptic currents, suggesting a presynaptic action. Multiphoton imaging of CeA-CRF neurons in rat brain slices showed that U-69,593 increased calcium signals evoked by electrical stimulation of presumed parabrachial input. This study shows for the first time that KOR activation increases activity of amygdala CRF neurons through synaptic disinhibition, resulting in averse-affective pain-like behaviors. Blocking KOR receptors may therefore represent a novel therapeutic strategy.
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Affiliation(s)
- Matthew Hein
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Guangchen Ji
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Dalton Tidwell
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Preston D'Souza
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Takaki Kiritoshi
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Vadim Yakhnitsa
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Edita Navratilova
- Department of Pharmacology, Arizona Health Sciences Center, University of Arizona, Tucson, AZ, USA
| | - Frank Porreca
- Department of Pharmacology, Arizona Health Sciences Center, University of Arizona, Tucson, AZ, USA
| | - Volker Neugebauer
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
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48
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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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49
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Negus SS, Marsh SA, Townsend EA. Resistance of Food-Maintained Operant Responding to Mechanical Punishment in Rats: Further Evidence for Weak "Affective/Motivational Pain" in Rat Models of Inflammatory and Neuropathic Pain. Front Pharmacol 2021; 11:615782. [PMID: 33584295 PMCID: PMC7878562 DOI: 10.3389/fphar.2020.615782] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/29/2020] [Indexed: 01/25/2023] Open
Abstract
Clinically relevant chronic pain is often associated with functional impairment and behavioral depression as an “affective/motivational” sign of pain; however preclinical animal models of inflammatory and neuropathic pain often produce weak evidence of impaired function. We hypothesized that hindpaw mechanical stimulation produced by a requirement to rear on a textured “NOX” plate would punish operant responding in rats treated with intraplantar complete Freund’s adjuvant (CFA, a model of inflammatory pain) or the chemotherapeutic paclitaxel (PTX, a model of neuropathic pain) and produce sustained pain-related depression of operant behavior. Male Sprague–Dawley rats were trained under a progressive-ratio (PR) schedule of food-maintained operant responding, then treated with CFA (100 µL in left hindpaw), PTX (2.0 mg/kg IP on alternate days for four total injections; 6.6 mg/kg IV on alternate days for three total injections), or saline vehicle. PR break points and mechanical thresholds for paw withdrawal from von Frey filaments were then tracked for 28 days. Subsequently, rats were tested with the opioid receptor antagonist naltrexone to assess latent sensitization and with the kappa opioid receptor (KOR) agonist U69593 to assess KOR function. CFA produced significant mechanical hypersensitivity for 3 weeks but decreased PR breakpoints for only 1 day. Both IP and IV PTX produced mechanical hypersensitivity for at least three weeks; however, only IV PTX decreased PR breakpoints, and this decrease was not alleviated by morphine. After recovery, naltrexone reinstated mechanical hypersensitivity in CFA- but not PTX-treated rats, and it did not reinstate depression of breakpoints in any group. U69593 dose-dependently decreased PR breakpoints in all groups with no difference between control vs. CFA/PTX groups. These results suggest that rearing on a textured NOX plate was not sufficient to punish operant responding in CFA- and PTX-treated rats despite the presence of sustained mechanical hypersensitivity. The rapid recovery of operant responding could not be attributed to latent sensitization, KOR downregulation, or behavioral tolerance. These results extend the range of conditions under which putative chronic pain manipulations produce weak evidence for depression of operant responding as a sign of the “affective/motivational” component of pain in rats.
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Affiliation(s)
- S Stevens Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States
| | - S A Marsh
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States
| | - E A Townsend
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, United States
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50
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Lueptow LM, Shashkova EC, Miller MG, Evans CJ, Cahill CM. Insights into the Neurobiology of Craving in Opioid Use Disorder. CURRENT ANESTHESIOLOGY REPORTS 2021; 10:378-387. [PMID: 33424457 DOI: 10.1007/s40140-020-00420-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Purpose of review Opioids remain the most potent form of pain relief currently available, yet have a high abuse liability. Here we discuss underlying neurobiological changes in Opioid Use Disorder (OUD) that likely contribute to drug craving, which in turn drives continued drug use and relapse. Recent findings Craving has emerged as a strong indicator in drug-seeking and relapse. Studies have demonstrated a number of allostatic changes in circuitry that facilitate learning of drug-stimuli relationships, thereby augmenting cue-triggered drug use and relapse. Summary This review will focus on key neurobiological changes in underlying circuitry observed during the initial and continued exposure to opioids that result in an increase in neural-reactivity to drug-related intrinsic and extrinsic drug cues, and to enhanced learning of drug-context correlations. This sensitized learning state may be an indication of the underlying framework that drives craving and ultimately, motivates increased salience of drug cues and drives drug-seeking.
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Affiliation(s)
- Lindsay M Lueptow
- Department of Psychiatry and Biobehavioral Sciences, Los Angeles, CA, 90095, USA.,Shirley and Stefan Hatos Center for Neuropharmacology, Los Angeles, CA, 90095, USA.,Department of Psychology at University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Elizabeth C Shashkova
- Shirley and Stefan Hatos Center for Neuropharmacology, Los Angeles, CA, 90095, USA.,David Geffen School of Medicine, Los Angeles, CA, 90095, USA
| | - Margaret G Miller
- Shirley and Stefan Hatos Center for Neuropharmacology, Los Angeles, CA, 90095, USA.,David Geffen School of Medicine, Los Angeles, CA, 90095, USA
| | - Christopher J Evans
- Department of Psychiatry and Biobehavioral Sciences, Los Angeles, CA, 90095, USA.,Shirley and Stefan Hatos Center for Neuropharmacology, Los Angeles, CA, 90095, USA.,Jane & Terry Semel Institute for Neuroscience and Human Behavior, Los Angeles, CA, 90095, USA.,David Geffen School of Medicine, Los Angeles, CA, 90095, USA
| | - Catherine M Cahill
- Department of Psychiatry and Biobehavioral Sciences, Los Angeles, CA, 90095, USA.,Shirley and Stefan Hatos Center for Neuropharmacology, Los Angeles, CA, 90095, USA.,Jane & Terry Semel Institute for Neuroscience and Human Behavior, Los Angeles, CA, 90095, USA.,David Geffen School of Medicine, Los Angeles, CA, 90095, USA
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