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Murray CH, Gannon BM, Winsauer PJ, Cooper ZD, Delatte MS. The Development of Cannabinoids as Therapeutic Agents in the United States. Pharmacol Rev 2024; 76:915-955. [PMID: 38849155 DOI: 10.1124/pharmrev.123.001121] [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: 11/10/2023] [Revised: 05/30/2024] [Accepted: 06/03/2024] [Indexed: 06/09/2024] Open
Abstract
Cannabis is one of the oldest and widely used substances in the world. Cannabinoids within the cannabis plant, known as phytocannabinoids, mediate cannabis' effects through interactions with the body's endogenous cannabinoid system. This endogenous system, the endocannabinoid system, has important roles in physical and mental health. These roles point to the potential to develop cannabinoids as therapeutic agents while underscoring the risks related to interfering with the endogenous system during nonmedical use. This scoping narrative review synthesizes the current evidence for both the therapeutic and adverse effects of the major (i.e., Δ9-tetrahydrocannabinol and cannabidiol) and lesser studied minor phytocannabinoids, from nonclinical to clinical research. We pay particular attention to the areas where evidence is well established, including analgesic effects after acute exposures and neurocognitive risks after acute and chronic use. In addition, drug development considerations for cannabinoids as therapeutic agents within the United States are reviewed. The proposed clinical study design considerations encourage methodological standards for greater scientific rigor and reproducibility to ultimately extend our knowledge of the risks and benefits of cannabinoids for patients and providers. SIGNIFICANCE STATEMENT: This work provides a review of prior research related to phytocannabinoids, including therapeutic potential and known risks in the context of drug development within the United States. We also provide study design considerations for future cannabinoid drug development.
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Affiliation(s)
- Conor H Murray
- UCLA Center for Cannabis and Cannabinoids, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences (C.H.M.) and Departments of Anesthesiology and Perioperative Medicine (Z.D.C.), David Geffen School of Medicine, University of California, Los Angeles, California; Department of Pharmacology and Toxicology, College of Medicine (B.M.G.) and Office of Research Regulatory Affairs, Division of Research and Innovation (B.M.G.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Departments of Pharmacology and Experimental Therapeutics and Biochemistry and Molecular Biology, School of Medicine (P.J.W.), and Alcohol and Drug Abuse Center of Excellence (P.J.W.) Louisiana State University Health Sciences Center, New Orleans, Louisiana; and Regulatory and Drug Development Consulting, Allucent, Carey, North Carolina (M.S.D.)
| | - Brenda M Gannon
- UCLA Center for Cannabis and Cannabinoids, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences (C.H.M.) and Departments of Anesthesiology and Perioperative Medicine (Z.D.C.), David Geffen School of Medicine, University of California, Los Angeles, California; Department of Pharmacology and Toxicology, College of Medicine (B.M.G.) and Office of Research Regulatory Affairs, Division of Research and Innovation (B.M.G.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Departments of Pharmacology and Experimental Therapeutics and Biochemistry and Molecular Biology, School of Medicine (P.J.W.), and Alcohol and Drug Abuse Center of Excellence (P.J.W.) Louisiana State University Health Sciences Center, New Orleans, Louisiana; and Regulatory and Drug Development Consulting, Allucent, Carey, North Carolina (M.S.D.)
| | - Peter J Winsauer
- UCLA Center for Cannabis and Cannabinoids, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences (C.H.M.) and Departments of Anesthesiology and Perioperative Medicine (Z.D.C.), David Geffen School of Medicine, University of California, Los Angeles, California; Department of Pharmacology and Toxicology, College of Medicine (B.M.G.) and Office of Research Regulatory Affairs, Division of Research and Innovation (B.M.G.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Departments of Pharmacology and Experimental Therapeutics and Biochemistry and Molecular Biology, School of Medicine (P.J.W.), and Alcohol and Drug Abuse Center of Excellence (P.J.W.) Louisiana State University Health Sciences Center, New Orleans, Louisiana; and Regulatory and Drug Development Consulting, Allucent, Carey, North Carolina (M.S.D.)
| | - Ziva D Cooper
- UCLA Center for Cannabis and Cannabinoids, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences (C.H.M.) and Departments of Anesthesiology and Perioperative Medicine (Z.D.C.), David Geffen School of Medicine, University of California, Los Angeles, California; Department of Pharmacology and Toxicology, College of Medicine (B.M.G.) and Office of Research Regulatory Affairs, Division of Research and Innovation (B.M.G.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Departments of Pharmacology and Experimental Therapeutics and Biochemistry and Molecular Biology, School of Medicine (P.J.W.), and Alcohol and Drug Abuse Center of Excellence (P.J.W.) Louisiana State University Health Sciences Center, New Orleans, Louisiana; and Regulatory and Drug Development Consulting, Allucent, Carey, North Carolina (M.S.D.)
| | - Marcus S Delatte
- UCLA Center for Cannabis and Cannabinoids, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences (C.H.M.) and Departments of Anesthesiology and Perioperative Medicine (Z.D.C.), David Geffen School of Medicine, University of California, Los Angeles, California; Department of Pharmacology and Toxicology, College of Medicine (B.M.G.) and Office of Research Regulatory Affairs, Division of Research and Innovation (B.M.G.), University of Arkansas for Medical Sciences, Little Rock, Arkansas; Departments of Pharmacology and Experimental Therapeutics and Biochemistry and Molecular Biology, School of Medicine (P.J.W.), and Alcohol and Drug Abuse Center of Excellence (P.J.W.) Louisiana State University Health Sciences Center, New Orleans, Louisiana; and Regulatory and Drug Development Consulting, Allucent, Carey, North Carolina (M.S.D.)
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Rêgo DSB, Calió ML, Filev R, Mello LE, Leslie ATFS. Long-term Effects of Cannabidiol and/or Fentanyl Exposure in Rats Submitted to Neonatal Pain. THE JOURNAL OF PAIN 2024; 25:715-729. [PMID: 37820846 DOI: 10.1016/j.jpain.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 09/13/2023] [Accepted: 10/02/2023] [Indexed: 10/13/2023]
Abstract
The current study aimed to evaluate anxiety behavior, hippocampal ionized calcium-binding adaptor molecule 1 (Iba1) and cannabinoid receptor 1 (CB1) gene expression, and nociceptive response in adulthood after a combination of fentanyl and cannabidiol (CBD) for nociceptive stimuli induced during the first week of life in rats. Complete Freund's adjuvant-induced inflammatory nociceptive insult on postnatal day (PN) 1 and PN3. Both fentanyl and CBD were used alone or in combination from PN1 to PN7. Behavioral and nociceptive tests were performed at PN60 and PN62. The expression of the microglial calcium-binding proteins Iba1 and CB1 was detected in the hippocampus using reverse Quantitative polymerase chain reaction (qPCR) and immunohistochemistry. Our results suggest that the anxiety behavior response and immune activation in adult life depend on the CBD dose combined with fentanyl for the nociceptive stimuli induced during the first week of life. Treatment of neonatal nociceptive insult with CBD and opioids showed significant dose-dependent and male-female differences. The increased gene expression in the hippocampus of the analyzed cannabinoid gene supports this data. In addition, treatment with fentanyl led to an increase in CB1 protein expression. Moreover, the expression of Iba1 varied according to the administered dose of CBD and may or may not be associated with the opioid. A lower dose of CBD during the inflammatory period was associated with enhanced anxiety in adult life. PERSPECTIVE: The treatment of nociceptive stimuli with CBD and opioids during the first week of life demonstrated significant sex differences in adult life on anxiety behavior and supraspinal pain sensitivity.
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Affiliation(s)
- Débora S B Rêgo
- Department of Physiology, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Michele Longoni Calió
- Department of Physiology, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Renato Filev
- Programa de Orientação e Atendimento a Dependentes (PROAD), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Luiz E Mello
- Department of Physiology, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil; Instituto D'Or de Pesquisa e Ensino, Rio de Janeiro, Brazil
| | - Ana T F S Leslie
- Department of Physiology, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
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Pearl-Dowler L, Posa L, Lopez-Canul M, Teggin A, Gobbi G. Anti-allodynic and medullary modulatory effects of a single dose of delta-9-tetrahydrocannabinol (THC) in neuropathic rats tolerant to morphine. Prog Neuropsychopharmacol Biol Psychiatry 2023; 127:110805. [PMID: 37257771 DOI: 10.1016/j.pnpbp.2023.110805] [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: 01/13/2023] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/02/2023]
Abstract
Neuropathic pain (NP) is often treated with opioids, the prolonged use of which causes tolerance to their analgesic effect and can potentially cause death by overdose. The phytocannabinoid delta-9-tetrahydrocannabinol (THC) may be an effective alternative analgesic to treat NP in morphine-tolerant subjects. Male Wistar rats developed NP after spared nerve injury, and were then treated with increasing doses of THC (1, 1.5, 2, 2.5, and 5 mg/kg, intraperitoneally), which reduced mechanical allodynia at the dose of 2.5 and 5 mg/kg. Another group of NP rats were treated with morphine (5 mg/kg, twice daily for 7 days, subcutaneously), until tolerance developed, and on day 8 received a single dose of THC (2.5 mg/kg), which significantly reduced mechanical allodynia. To evaluate the modulation of THC in the descending pain pathway, in vivo electrophysiological recordings of pronociceptive ON cells and antinociceptive OFF cells in the rostroventral medulla (RVM) were recorded after intra-PAG microinjection of THC (10 μg/μl). NP rats with morphine tolerance, compared to the control one, showed a tonic reduction of the spontaneous firing rate of ON cells by 44%, but the THC was able to further decrease it (a hallmark of many analgesic drugs acting at supraspinal level). On the other hand, the firing rate, of the antinociceptive OFF cells was increased after morphine tolerance by 133%, but the THC failed to further activate it. Altogether, these findings indicate that a single dose of THC produces antiallodynic effect in individuals with NP who are tolerant to morphine, acting mostly on the ON cells of the descending pain pathways, but not on OFF cells.
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Affiliation(s)
- Leora Pearl-Dowler
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC, Canada
| | - Luca Posa
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Martha Lopez-Canul
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC, Canada
| | - Alexandra Teggin
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC, Canada
| | - Gabriella Gobbi
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada.
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Slivicki RA, Wang JG, Nhat VTT, Kravitz AV, Creed MC, Gereau RW. Impact of Δ 9-Tetrahydrocannabinol and oxycodone co-administration on measures of antinociception, dependence, circadian activity, and reward in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.04.569809. [PMID: 38105953 PMCID: PMC10723318 DOI: 10.1101/2023.12.04.569809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Oxycodone is commonly prescribed for moderate to severe pain disorders. While efficacious, long-term use can result in tolerance, physical dependence, and the development of opioid use disorder. Cannabis and its derivatives such as Δ9-Tetrahydrocannabinol (Δ9-THC) have been reported to enhance oxycodone analgesia in animal models and in humans. However, it remains unclear if Δ9-THC may facilitate unwanted aspects of oxycodone intake, such as tolerance, dependence, and reward at analgesic doses. This study sought to evaluate the impact of co-administration of Δ9-THC and oxycodone across behavioral measures related to antinociception, dependence, circadian activity, and reward in both male and female mice. Oxycodone and Δ9-THC produced dose-dependent antinociceptive effects in the hotplate assay that were similar between sexes. Repeated treatment (twice daily for 5 days) resulted in antinociceptive tolerance. Combination treatment of oxycodone and Δ9-THC produced a greater antinociceptive effect than either administered alone, and delayed the development of antinociceptive tolerance. Repeated treatment with oxycodone produced physical dependence and alterations in circadian activity, neither of which were exacerbated by co-treatment with Δ9-THC. Combination treatment of oxycodone and Δ9-THC produced CPP when co-administered at doses that did not produce preference when administered alone. These data indicate that Δ9-THC may facilitate oxycodone-induced antinociception without augmenting certain unwanted features of opioid intake (e.g. dependence, circadian rhythm alterations). However, our findings also indicate that Δ9-THC may facilitate rewarding properties of oxycodone at therapeutically relevant doses which warrant consideration when evaluating this combination for its potential therapeutic utility.
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Affiliation(s)
- Richard A. Slivicki
- Washington University Pain Center and Department of Anesthesiology, Washington University, St. Louis, MO
| | - Justin G. Wang
- Washington University Pain Center and Department of Anesthesiology, Washington University, St. Louis, MO
- Neuroscience Graduate Program, Division of Biology & Biomedical Sciences, Washington University, St. Louis, MO
| | - Vy Trinh Tran Nhat
- Washington University Pain Center and Department of Anesthesiology, Washington University, St. Louis, MO
| | - Alexxai V. Kravitz
- Washington University Pain Center and Department of Anesthesiology, Washington University, St. Louis, MO
- Department of Psychiatry, Washington University, St. Louis, MO
- Department of Neuroscience, Washington University, St. Louis, MO
| | - Meaghan C. Creed
- Washington University Pain Center and Department of Anesthesiology, Washington University, St. Louis, MO
- Department of Neuroscience, Washington University, St. Louis, MO
| | - Robert W. Gereau
- Washington University Pain Center and Department of Anesthesiology, Washington University, St. Louis, MO
- Department of Neuroscience, Washington University, St. Louis, MO
- Department of Biomedical Engineering, Washington University, St. Louis, MO
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Lee MT, Mackie K, Chiou LC. Alternative pain management via endocannabinoids in the time of the opioid epidemic: Peripheral neuromodulation and pharmacological interventions. Br J Pharmacol 2023; 180:894-909. [PMID: 34877650 PMCID: PMC9170838 DOI: 10.1111/bph.15771] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 11/23/2021] [Accepted: 11/27/2021] [Indexed: 01/18/2023] Open
Abstract
The use of opioids in pain management is hampered by the emergence of analgesic tolerance, which leads to increased dosing and side effects, both of which have contributed to the opioid epidemic. One promising potential approach to limit opioid analgesic tolerance is activating the endocannabinoid system in the CNS, via activation of CB1 receptors in the descending pain inhibitory pathway. In this review, we first discuss preclinical and clinical evidence revealing the potential of pharmacological activation of CB1 receptors in modulating opioid tolerance, including activation by phytocannabinoids, synthetic CB1 receptor agonists, endocannabinoid degradation enzyme inhibitors, and recently discovered positive allosteric modulators of CB1 receptors. On the other hand, as non-pharmacological pain relief is advocated by the US-NIH to combat the opioid epidemic, we also discuss contributions of peripheral neuromodulation, involving the electrostimulation of peripheral nerves, in addressing chronic pain and opioid tolerance. The involvement of supraspinal endocannabinoid systems in peripheral neuromodulation-induced analgesia is also discussed. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.
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Grants
- MOST 108-2321-B-002-005 Ministry of Science and Technology, Taiwan
- MOST 107-2811-B-002-008 Ministry of Science and Technology, Taiwan
- R01 DA041229 NIDA NIH HHS
- MOST 107-2321-B-002-010 Ministry of Science and Technology, Taiwan
- R01 DA047858 NIDA NIH HHS
- 107M4022-3 Ministry of Education, Taiwan
- MOST 106-2321-B-002-019 Ministry of Science and Technology, Taiwan
- NHRI-EX111-11114NI National Health Research Institutes, Taiwan
- FRGS/1/2021/WAB13/UCSI/02/1 Ministry of Higher Education, Malaysia
- R21 DA042584 NIDA NIH HHS
- REIG-FPS-2020/065 UCSI University Research Excellence and Innovation Grant, Malaysia
- NHRI-EX109-10733NI National Health Research Institutes, Taiwan
- MOST 104-2745-B-002-004 Ministry of Science and Technology, Taiwan
- MOST 109-2320-B-002-042-MY3 Ministry of Science and Technology, Taiwan
- MOST 107-2811-B-002 -008 Ministry of Science and Technology, Taiwan
- MOST 108-2320-B-002-029-MY3 Ministry of Science and Technology, Taiwan
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Affiliation(s)
- Ming Tatt Lee
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
- Faculty of Pharmaceutical Sciences, UCSI University, Kuala Lumpur 56000, Malaysia
| | - Ken Mackie
- Gill Center for Biomolecular Research, Indiana University, Bloomington, Indiana 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405, USA
| | - Lih-Chu Chiou
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
- Graduate Institute of Brain and Mind Sciences, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
- Graduate Institute of Acupuncture Science, China Medical University, Taichung 40402, Taiwan
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Rivera-Garcia MT, Rose RM, Wilson-Poe AR. High-CBD Cannabis Vapor Attenuates Opioid Reward and Partially Modulates Nociception in Female Rats. ADDICTION NEUROSCIENCE 2023; 5:100050. [PMID: 36937502 PMCID: PMC10019487 DOI: 10.1016/j.addicn.2022.100050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chronic pain patients report analgesic effects when using cannabidiol (CBD), a phytocannabinoid found in whole-plant cannabis extract (WPE). Several studies suggest that cannabis-derived products may serve as an analgesic adjunct or alternative to opioids, and importantly, CBD may also attenuate the abuse potential of opioids. Vaping is a popular route of administration among people who use cannabis, however both the therapeutic and hazardous effects of vaping are poorly characterized. Despite the fact that chronic pain is more prevalent in women, the ability of inhaled high-CBD WPE to relieve pain and reduce opioid reward has not been studied in females. Here, we present a comprehensive analysis of high-CBD WPE vapor inhalation in female rats. We found that WPE was modestly efficacious in reversing neuropathy-induced cold allodynia in rats with spared nerve injury (SNI). Chronic exposure to WPE did not affect lung cytoarchitecture or estrous cycle, and it did not induce cognitive impairment, social withdrawal or anxiolytic effects. WPE inhalation prevented morphine-induced conditioned place preference and reinstatement. Similarly, WPE exposure reduced fentanyl self-administration in rats with and without neuropathic pain. We also found that WPE vapor lacks of reinforcing effects compared to the standard excipient used in most vapor administration research. Combined, these results suggest that although high-CBD vapor has modest analgesic effects, it has a robust safety profile, no abuse potential, and it significantly reduces opioid reward in females. Clinical studies examining high-CBD WPE as an adjunct treatment during opioid use disorder are highly warranted.
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Affiliation(s)
- Maria T Rivera-Garcia
- RS Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Rizelle Mae Rose
- RS Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, United States
| | - Adrianne R Wilson-Poe
- RS Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, United States
- Integrative Physiology and Neuroscience, Washington State University
- Corresponding author. Adrianne R Wilson-Poe, Ph.D., 1225 NE 2nd Ave, suite 249, Portland, OR 97232, USA. Tel. (503) 413-1754, (A.R. Wilson-Poe)
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Carey LM, Maguire DR, France CP. Effects of Δ⁹-tetrahydrocannabinol (THC), cannabidiol (CBD), and THC/CBD mixtures on fentanyl versus food choice in rhesus monkeys. Drug Alcohol Depend 2023; 244:109787. [PMID: 36753805 PMCID: PMC10697211 DOI: 10.1016/j.drugalcdep.2023.109787] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 01/22/2023] [Accepted: 01/23/2023] [Indexed: 02/04/2023]
Abstract
INTRODUCTION There is considerable interest in utilizing cannabis-based products as adjuvants to opioid agonist therapies as phytocannabinoids like Δ9-tetrahydrocannabinol (THC) or synthetic cannabinoid receptor agonists appear to enhance the pain-relieving effects of opioids without enhancing problematic effects of opioids. Cannabis is a pharmacologically complex plant with hundreds of compounds, some of which may have interactive effects. Therefore, studying compounds like THC in isolation does not accurately reflect the clinical use of cannabis. METHODS This study examined the effects of THC and cannabidiol (CBD), the two most prominent compounds in cannabis, on the reinforcing effects of fentanyl in rhesus monkeys in a food versus drug choice procedure. Responding on one lever was reinforced by delivery of a sucrose pellet, and responding on another lever was reinforced by delivery of an i.v. infusion of fentanyl. In each monkey, the largest dose of fentanyl that produced less than 20 % drug choice and the smallest dose of fentanyl that produced more than 80% drug choice was determined. Effects of pretreatment with THC and CBD, alone and in mixtures, were then examined. RESULTS THC, CBD, and THC:CBD mixtures did not reliably enhance or diminish choice for fentanyl up to doses that suppressed responding in most monkeys, though some individual differences were observed, with THC and THC:CBD mixtures decreasing choice for large doses of fentanyl in one monkey and increasing choice for small doses of fentanyl in another. CONCLUSIONS Phytocannabinoids like THC and CBD, administered alone or in mixtures, do not appear to reliably alter the reinforcing effects of opioids.
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Affiliation(s)
- Lawrence M Carey
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - David R Maguire
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Charles P France
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Department of Psychiatry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
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Wiese BM, Liktor-Busa E, Couture SA, Nikas SP, Ji L, Liu Y, Makriyannis A, Spigelman I, Vanderah TW, Largent-Milnes TM. Brain Penetrant, but not Peripherally Restricted, Synthetic Cannabinoid 1 Receptor Agonists Promote Morphine-Mediated Respiratory Depression. Cannabis Cannabinoid Res 2022; 7:621-627. [PMID: 34935460 PMCID: PMC9587769 DOI: 10.1089/can.2021.0090] [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] [Indexed: 11/12/2022] Open
Abstract
Introduction: Cannabis acceptance and use continues to rise despite the gaps in knowledge regarding the mechanisms of cannabinoids and the endocannabinoid system in many physiological functions, including respiratory influence. Methods: With recent evidence of cannabinoid receptor 1 (CB1R) presence in the collection of respiratory neurons in the brainstem, as well as in the peripheral lung tissue, it is vital that the mechanisms involved in central and peripheral CB1R modulation of respiratory function be delineated. In this study we sought to define the roles of central versus peripheral CB1R activation on respiratory depression alone and in combination with morphine using whole body plethysmography. Results: We show that the peripherally restricted CB1 agonist (4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3yl]ethyl}morpholine [PrNMI] 0.3, 0.6, and 1 mg/kg) does not induce respiratory depression, while our previous studies showed that a central penetrating synthetic cannabinoid does induce respiratory depression. Significantly, the combination of morphine with the peripheral CB1 agonist, PrNMI, attenuated morphine-induced respiratory depression. Conclusions: These studies support that a peripherally restricted CB1R agonist may be a unique strategy to attenuate the respiratory depression associated with opioid therapy.
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Affiliation(s)
- Beth M. Wiese
- Department of Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Erika Liktor-Busa
- Department of Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Sarah A. Couture
- Department of Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Spyros P. Nikas
- Chemistry and Chemical Biology, Bouve College Health Sciences—Center for Drug Discovery, Northeastern University, Boston, Massachusetts, USA
| | - Lipin Ji
- Chemistry and Chemical Biology, Bouve College Health Sciences—Center for Drug Discovery, Northeastern University, Boston, Massachusetts, USA
| | - Yingpeng Liu
- Chemistry and Chemical Biology, Bouve College Health Sciences—Center for Drug Discovery, Northeastern University, Boston, Massachusetts, USA
| | - Alexandros Makriyannis
- Chemistry and Chemical Biology, Bouve College Health Sciences—Center for Drug Discovery, Northeastern University, Boston, Massachusetts, USA
| | - Igor Spigelman
- Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, California, USA
| | - Todd W. Vanderah
- Department of Pharmacology, University of Arizona, Tucson, Arizona, USA
- Comprehensive Pain and Addiction Center, University of Arizona, Health Sciences, Tucson, Arizona, USA
| | - Tally M. Largent-Milnes
- Department of Pharmacology, University of Arizona, Tucson, Arizona, USA
- Comprehensive Pain and Addiction Center, University of Arizona, Health Sciences, Tucson, Arizona, USA
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Zubrzycki M, Zubrzycka M, Wysiadecki G, Szemraj J, Jerczynska H, Stasiolek M. Effect of Fatty Acid Amide Hydrolase Inhibitor URB597 on Orofacial Pain Perception in Rats. Int J Mol Sci 2022; 23:4665. [PMID: 35563056 PMCID: PMC9100922 DOI: 10.3390/ijms23094665] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/13/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
Endocannabinoids act as analgesic agents in a number of headache models. However, their effectiveness varies with the route of administration and the type of pain. In this study, we assessed the role of the fatty acid amide hydrolase inhibitor URB597 in an animal model of orofacial pain based on tooth pulp stimulation. More specifically, we assessed the effects of intracerbroventricular (i.c.v.) and intraperitoneal (i.p.) administration of URB597 on the amplitude of evoked tongue jerks (ETJ) in rats. The levels of the investigated mediators anandamide (AEA), 2-arachidonyl glycerol (2-AG), Substance P (SP), calcitonin-gene-related peptide (CGRP), endomorphin-2 (EM-2) and fatty acid amide hydrolase (FAAH) inhibitor by URB597 and receptors cannabinoid type-1 receptors (CB1R), cannabinoid type-2 receptors (CB2R) and µ-opioid receptors (MOR) were determined in the mesencephalon, thalamus and hypothalamus tissues. We have shown that increasing endocannabinoid AEA levels by both central and peripheral inhibition of FAAH inhibitor by URB597 has an antinociceptive effect on the trigemino-hypoglossal reflex mediated by CB1R and influences the activation of the brain areas studied. On the other hand, URB597 had no effect on the concentration of 2-AG in the examined brain structures and caused a significant decrease in CB2R mRNA expression in the hypothalamus only. Tooth pulp stimulation caused in a significant increase in SP, CGRP and EM-2 gene expression in the midbrain, thalamus and hypothalamus. In contrast, URB597 administered peripherally one hour before stimulation decreased the mRNA level of these endogenous neuropeptides in comparison with the control and stimulation in all examined brain structures. Our results show that centrally and peripherally administered URB597 is effective at preventing orofacial pain by inhibiting AEA catabolism and reducing the level of CGRP, SP and EM-2 gene expression and that AEA and 2-AG have different species and model-specific regulatory mechanisms. The data presented in this study may represent a new promising therapeutic target in the treatment of orofacial pain.
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Affiliation(s)
- Marek Zubrzycki
- Department of Cardiac Surgery and Transplantology, The Cardinal Stefan Wyszynski Institute of Cardiology, Alpejska 42, 04-628 Warsaw, Poland
| | - Maria Zubrzycka
- Department of Clinical Physiology, Faculty of Medicine, Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland;
| | - Grzegorz Wysiadecki
- Department of Normal and Clinical Anatomy, Chair of Anatomy and Histology, Medical University of Lodz, Żeligowskiego 7/9, 90-752 Lodz, Poland;
| | - Janusz Szemraj
- Department of Medical Biochemistry, Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland;
| | - Hanna Jerczynska
- Central Scientific Laboratory (CoreLab), Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland;
| | - Mariusz Stasiolek
- Department of Neurology, Medical University of Lodz, Kopcinskiego 22, 90-153 Lodz, Poland;
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10
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Greco R, Demartini C, Zanaboni AM, Francavilla M, De Icco R, Ahmad L, Tassorelli C. The endocannabinoid system and related lipids as potential targets for the treatment of migraine-related pain. Headache 2022; 62:227-240. [PMID: 35179780 DOI: 10.1111/head.14267] [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: 09/02/2021] [Revised: 12/10/2021] [Accepted: 12/23/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND Migraine is a complex and highly disabling neurological disease whose treatment remains challenging in many patients, even after the recent advent of the first specific-preventive drugs, namely monoclonal antibodies that target calcitonin gene-related peptide. For this reason, headache researchers are actively searching for new therapeutic targets. Cannabis has been proposed for migraine treatment, but controlled clinical studies are lacking. A major advance in cannabinoid research has been the discovery of the endocannabinoid system (ECS), which consists of receptors CB1 and CB2; their endogenous ligands, such as N-arachidonoylethanolamine; and the enzymes that catalyze endocannabinoid biosynthesis or degradation. Preclinical and clinical findings suggest a possible role for endocannabinoids and related lipids, such as palmitoylethanolamide (PEA), in migraine-related pain treatment. In animal models of migraine-related pain, endocannabinoid tone modulation via inhibition of endocannabinoid-catabolizing enzymes has been a particular focus of research. METHODS To conduct a narrative review of available data on the possible effects of cannabis, endocannabinoids, and other lipids in migraine-related pain, relevant key words were used to search the PubMed/MEDLINE database for basic and clinical studies. RESULTS Endocannabinoids and PEA seem to reduce trigeminal nociception by interacting with many pathways associated with migraine, suggesting a potential synergistic or similar effect. CONCLUSIONS Modulation of the metabolic pathways of the ECS may be a basis for new migraine treatments. The multiplicity of options and the wealth of data already obtained in animal models underscore the importance of further advancing research in this area. Multiple molecules related to the ECS or to allosteric modulation of CB1 receptors have emerged as potential therapeutic targets in migraine-related pain. The complexity of the ECS calls for accurate biochemical and pharmacological characterization of any new compounds undergoing testing and development.
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Affiliation(s)
- Rosaria Greco
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Chiara Demartini
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Anna Maria Zanaboni
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy.,Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Miriam Francavilla
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Roberto De Icco
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy.,Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Lara Ahmad
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy.,Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Cristina Tassorelli
- Headache Science & Neurorehabilitation Center, IRCCS Mondino Foundation, Pavia, Italy.,Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
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11
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Wilson J, Mills K, Freeman TP, Sunderland M, Visontay R, Marel C. Weeding out the truth: a systematic review and meta-analysis on the transition from cannabis use to opioid use and opioid use disorders, abuse or dependence. Addiction 2022; 117:284-298. [PMID: 34264545 DOI: 10.1111/add.15581] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 01/18/2021] [Accepted: 05/12/2021] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND AIMS The idea that cannabis is a 'gateway drug' to more harmful substances such as opioids is highly controversial, yet has substantially impacted policy, education and how we conceptualize substance use. Given a rise in access to cannabis products and opioid-related harm, the current study aimed to conduct the first systematic review and meta-analysis on the likelihood of transitioning from cannabis use to subsequent first-time opioid use, opioid use disorders (OUD), dependence or abuse. METHODS Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, pubMed/MEDLINE, Scopus, EMBASE, PsychINFO, Cochrane Central Register of Controlled Trials and Informit Health Collection were searched for full-text articles assessing the likelihood of transitioning from cannabis to subsequent opioid use, and from opioid use to OUD, abuse or dependence given prior cannabis use. Analysis of subpopulations within studies were discussed narratively, and E-values were calculated to assess the potential influence of unmeasured confounding. FINDINGS Six studies provided relevant data from the United States, Australia and New Zealand between 1977 and 2017, a total sample of 102 461 participants. Random-effects analysis of the adjusted pooled effect size indicates that the likelihood of transitioning from cannabis to opioid use, relative to non-cannabis users, is odds ratio (OR) = 2.76, 95% confidence interval (CI) = 2.26-3.36, whereas the likelihood of transitioning from opioid use to OUD, abuse or dependence given prior cannabis use is OR = 2.52, 95% CI = 1.65-3.84. While the evidence was determined to be of low quality with moderate risk of bias, E-values suggest that these findings are robust against unmeasured confounding. CONCLUSION A systematic review and meta-analysis found that while people who use cannabis are disproportionately more likely to initiate opioid use and engage in problematic patterns of use than people who do not use cannabis, the low quality of the evidence must be considered when interpreting these findings.
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Affiliation(s)
- Jack Wilson
- The Matilda Centre for Research in Mental Health and Substance Use, The University of Sydney, Sydney, NSW, Australia
| | - Katherine Mills
- The Matilda Centre for Research in Mental Health and Substance Use, The University of Sydney, Sydney, NSW, Australia
| | - Tom P Freeman
- Addiction and Mental Health Group (AIM), University of Bath, Bath, UK
| | - Matthew Sunderland
- The Matilda Centre for Research in Mental Health and Substance Use, The University of Sydney, Sydney, NSW, Australia
| | - Rachel Visontay
- The Matilda Centre for Research in Mental Health and Substance Use, The University of Sydney, Sydney, NSW, Australia
| | - Christina Marel
- The Matilda Centre for Research in Mental Health and Substance Use, The University of Sydney, Sydney, NSW, Australia
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12
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Britch SC, Craft RM. No antinociceptive synergy between morphine and delta-9-tetrahydrocannabinol in male and female rats with persistent inflammatory pain. Behav Pharmacol 2021; 32:630-639. [PMID: 34561365 PMCID: PMC8578411 DOI: 10.1097/fbp.0000000000000657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Studies have demonstrated antinociceptive synergy between morphine and delta-9-tetrahydrocannabinol (THC) in animals, but whether such synergy occurs against all types of pain and in humans is unclear. Because a majority of chronic pain patients are women, and sex differences in morphine and THC potencies have been observed in rodents, the present study examined sex-specific effects of morphine and THC given alone and in combination, in rats with persistent inflammatory pain. On day 1, baseline mechanical and thermal response thresholds, hindpaw weight-bearing, locomotor activity, and hindpaw thickness were determined. Inflammation was then induced via hindpaw injection of complete Freund's adjuvant (CFA). Three days later, morphine (s.c.), THC (i.p) or a morphine-THC combination (1:1, 3:1 and 1:3 dose ratios) was administered, and behavioral testing was conducted at 30-240 min postinjection. Morphine alone was antiallodynic and antihyperalgesic, with no sex differences, but at some doses increased weight-bearing on the CFA-treated paw more in males than females. THC alone reduced mechanical allodynia with similar potency in both sexes, but reduced thermal hyperalgesia and locomotor activity with greater potency in females than males. All morphine-THC combinations reduced allodynia and hyperalgesia, but isobolographic analysis of mechanical allodynia data showed no significant morphine-THC synergy in either sex. Additionally, whereas morphine alone was antinociceptive at doses that did not suppress locomotion, morphine-THC combinations suppressed locomotion and did not increase weight-bearing on the inflamed paw. These results suggest that THC is unlikely to be a beneficial adjuvant when given in combination with morphine for reducing established inflammatory pain.
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Affiliation(s)
- Stevie C Britch
- Center on Drug and Alcohol Research, University of Kentucky
- Department of Behavioral Science, University of Kentucky, Lexington, Kentucky
| | - Rebecca M Craft
- Department of Psychology, Washington State University, Pullman, Washington, USA
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13
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Jan A, Gonçalves NP, Vaegter CB, Jensen PH, Ferreira N. The Prion-Like Spreading of Alpha-Synuclein in Parkinson's Disease: Update on Models and Hypotheses. Int J Mol Sci 2021; 22:8338. [PMID: 34361100 PMCID: PMC8347623 DOI: 10.3390/ijms22158338] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 12/11/2022] Open
Abstract
The pathological aggregation of the presynaptic protein α-synuclein (α-syn) and propagation through synaptically coupled neuroanatomical tracts is increasingly thought to underlie the pathophysiological progression of Parkinson's disease (PD) and related synucleinopathies. Although the precise molecular mechanisms responsible for the spreading of pathological α-syn accumulation in the CNS are not fully understood, growing evidence suggests that de novo α-syn misfolding and/or neuronal internalization of aggregated α-syn facilitates conformational templating of endogenous α-syn monomers in a mechanism reminiscent of prions. A refined understanding of the biochemical and cellular factors mediating the pathological neuron-to-neuron propagation of misfolded α-syn will potentially elucidate the etiology of PD and unravel novel targets for therapeutic intervention. Here, we discuss recent developments on the hypothesis regarding trans-synaptic propagation of α-syn pathology in the context of neuronal vulnerability and highlight the potential utility of novel experimental models of synucleinopathies.
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Affiliation(s)
- Asad Jan
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
| | - Nádia Pereira Gonçalves
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
- International Diabetic Neuropathy Consortium (IDNC), Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Christian Bjerggaard Vaegter
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
- International Diabetic Neuropathy Consortium (IDNC), Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Poul Henning Jensen
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
| | - Nelson Ferreira
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
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14
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Cuozzo M, Castelli V, Avagliano C, Cimini A, d’Angelo M, Cristiano C, Russo R. Effects of Chronic Oral Probiotic Treatment in Paclitaxel-Induced Neuropathic Pain. Biomedicines 2021; 9:biomedicines9040346. [PMID: 33808052 PMCID: PMC8066538 DOI: 10.3390/biomedicines9040346] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 12/12/2022] Open
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) represents one of the most prevalent and potentially disabling side effects due to the use of anticancer drugs, one of the primary neuropathies detected is peripheral neuropathy induced by administration of taxanes, including paclitaxel. It has been demonstrated that gut microbiota is crucial for the therapeutic effect of chemotherapeutic drugs for inhibiting tumor growth and contributed to the pathogenesis of the CIPN. The use of nutraceuticals has receiving growing attention from the research community due to their phytochemical, biological, and pharmacological properties. It has been demonstrated that probiotic formulations may both reduce inflammation and modulate the expression of pain receptors. Our studies tested the efficacy of a probiotic formulation, SLAB51, in preventing paclitaxel-induced neuropathy. Interestingly, our probiotic formulation was able to keep the gut integrity, preserving its functionality, in CIPN-mice, moreover, it prevented the mechanical and cold hypersensitivity induced in paclitaxel-mice. Additionally, ex-vivo analysis showed that in CIPN-mice the pro-biotic treatment increased the expression of opioid and cannabinoid receptors in spinal cord, it prevented in the reduction in nerve fiber damage in the paws and modulated the serum proinflammatory cytokines concentration. On basis of these data, the use of this specific probiotic formulation may represent a valid adjuvant agent to paclitaxel, useful and not toxic for long-lasting therapies.
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Affiliation(s)
- Mariarosaria Cuozzo
- Department of Pharmacy, University of Naples Federico II, 80131 Napoli, Italy; (M.C.); (C.A.); (R.R.)
| | - Vanessa Castelli
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (A.C.)
| | - Carmen Avagliano
- Department of Pharmacy, University of Naples Federico II, 80131 Napoli, Italy; (M.C.); (C.A.); (R.R.)
| | - Annamaria Cimini
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (A.C.)
- Sbarro Institute for Cancer Research and Molecular Medicine and Center for Biotechnology, Temple University, Philadelphia, PA 19122, USA
| | - Michele d’Angelo
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (A.C.)
- Correspondence: (M.d.); (C.C.)
| | - Claudia Cristiano
- Department of Pharmacy, University of Naples Federico II, 80131 Napoli, Italy; (M.C.); (C.A.); (R.R.)
- Task Force on Microbiome Studies, University of Naples “Federico II”, 80131 Naples, Italy
- Correspondence: (M.d.); (C.C.)
| | - Roberto Russo
- Department of Pharmacy, University of Naples Federico II, 80131 Napoli, Italy; (M.C.); (C.A.); (R.R.)
- Task Force on Microbiome Studies, University of Naples “Federico II”, 80131 Naples, Italy
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15
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Laksmidewi AAAP, Soejitno A. Endocannabinoid and dopaminergic system: the pas de deux underlying human motivation and behaviors. J Neural Transm (Vienna) 2021; 128:615-630. [PMID: 33712975 PMCID: PMC8105194 DOI: 10.1007/s00702-021-02326-y] [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: 11/21/2020] [Accepted: 03/04/2021] [Indexed: 01/11/2023]
Abstract
Endocannabinoid system (ECS) has been identified ever since cannabinoid, an active substance of Cannabis, was known to interact with endogenous cannabinoid (endocannabinoid/eCB) receptors. It later turned out that eCB was more intricate than previously thought. It has a pervasive role and exerts a multitude of cellular signaling mechanisms, regulating various physiological neurotransmission pathways in the human brain, including the dopaminergic (DA) system. eCB roles toward DA system were robust, clearly delineated, and reproducible with respect to physiological as well as pathological neurochemical and neurobehavioral manifestations of DA system, particularly those involving the nigrostriatal and mesocorticolimbic pathways. The eCB–DA system regulates the basics in the Maslow’s pyramid of hierarchy of needs required for individual survival such as food and sexual activity for reproductive purpose to those of higher needs in the pyramid, including self-actualization behaviors leading to achievement and reward (e.g., academic- and/or work-related performance and achievements). It is, thus, interesting to specifically discuss the eCB–DA system, not only on the molecular level, but also its tremendous potential to be developed as a future therapeutic strategy for various neuropsychiatric problems, including obesity, drug addiction and withdrawal, pathological hypersexuality, or low motivation behaviors.
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Affiliation(s)
- A A A Putri Laksmidewi
- Neurobehavioral and Cognitive Division, Neurology Department, Faculty of Medicine, Udayana University/Sanglah Hospital, Denpasar, Bali, Indonesia.
| | - Andreas Soejitno
- Neurobehavioral and Cognitive Division, Neurology Department, Faculty of Medicine, Udayana University/Sanglah Hospital, Denpasar, Bali, Indonesia
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16
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WeiWei Y, WenDi F, Mengru C, Tuo Y, Chen G. The cellular mechanism by which the rostral ventromedial medulla acts on the spinal cord during chronic pain. Rev Neurosci 2021; 32:545-558. [PMID: 33565739 DOI: 10.1515/revneuro-2020-0121] [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: 10/24/2020] [Accepted: 12/18/2020] [Indexed: 11/15/2022]
Abstract
Clinical therapies for chronic pain are limited. While targeted drugs are promising therapies for chronic pain, they exhibit insufficient efficacy and poor targeting. The occurrence of chronic pain partly results from central changes caused by alterations in neurons in the rostral ventromedial medulla (RVM) in the brainstem regulatory pathway. The RVM, which plays a key role in the descending pain control pathway, greatly contributes to the development and maintenance of pain. However, the exact roles of the RVM in chronic pain remain unclear, making it difficult to develop new drugs targeting the RVM and related pathways. Here, we first discuss the roles of the RVM and related circuits in chronic pain. Then, we analyze synaptic transmission between RVM neurons and spinal cord neurons, specifically focusing on the release of neurotransmitters, to explore the cellular mechanisms by which the RVM regulates chronic pain. Finally, we propose some ideas for the development of drugs targeting the RVM.
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Affiliation(s)
- Yu WeiWei
- Key Laboratory of Neuroregeneration of Jiangsu and the Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong226001, China
| | - Fei WenDi
- Key Laboratory of Neuroregeneration of Jiangsu and the Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong226001, China
| | - Cui Mengru
- Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong226001, China
| | - Yang Tuo
- Department of Hand Surgery, China-Japan Union Hospital of Jilin University, Changchun130033, China
| | - Gang Chen
- Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong226001, China.,Department of Tissue and Embryology, Medical School of Nantong University, Co-innovation Center of Neuroregeneration, Nantong University, Nantong226001, China
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17
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Mohammadkhani A, Borgland SL. Cellular and behavioral basis of cannabinioid and opioid interactions: Implications for opioid dependence and withdrawal. J Neurosci Res 2020; 100:278-296. [PMID: 33352618 DOI: 10.1002/jnr.24770] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 01/22/2023]
Abstract
The brain's endogenous opioid and endocannabinoid systems are neuromodulatory of synaptic transmission, and play key roles in pain, memory, reward, and addiction. Recent clinical and pre-clinical evidence suggests that opioid use may be reduced with cannabinoid intake. This suggests the presence of a functional interaction between these two systems. Emerging research indicates that cannabinoids and opioids can functionally interact at different levels. At the cellular level, opioid and cannabinoids can have direct receptor associations, alterations in endogenous opioid peptide or cannabinoid release, or post-receptor activation interactions via shared signal transduction pathways. At the systems level, the nature of cannabinoid and opioid interaction might differ in brain circuits underlying different behavioral phenomenon, including reward-seeking or antinociception. Given the rising use of opioid and cannabinoid drugs, a better understanding of how these endogenous signaling systems interact in the brain is of significant interest. This review focuses on the potential relationship of these neural systems in addiction-related processes.
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Affiliation(s)
- Aida Mohammadkhani
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, Canada
| | - Stephanie L Borgland
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, Canada
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18
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Bouchet CA, Ingram SL. Cannabinoids in the descending pain modulatory circuit: Role in inflammation. Pharmacol Ther 2020; 209:107495. [PMID: 32004514 PMCID: PMC7183429 DOI: 10.1016/j.pharmthera.2020.107495] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/17/2020] [Indexed: 01/09/2023]
Abstract
The legalization of cannabis in some states has intensified interest in the potential for cannabis and its constituents to lead to novel therapeutics for pain. Our understanding of the cellular mechanisms underlying cannabinoid actions in the brain have lagged behind opioids; however, the current opioid epidemic has also increased attention on the use of cannabinoids as alternatives to opioids for pain, especially chronic pain that requires long-term use. Endogenous cannabinoids are lipid signaling molecules that have complex roles in modulating neuronal function throughout the brain. In this review, we discuss cannabinoid functions in the descending pain modulatory pathway, a brain circuit that integrates cognitive and emotional processing of pain to modulate incoming sensory inputs. In addition, we highlight areas where further studies are necessary to understand cannabinoid regulation of descending pain modulation.
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Affiliation(s)
- Courtney A Bouchet
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, United States of America
| | - Susan L Ingram
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, United States of America.
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19
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Schurman LD, Lu D, Kendall DA, Howlett AC, Lichtman AH. Molecular Mechanism and Cannabinoid Pharmacology. Handb Exp Pharmacol 2020; 258:323-353. [PMID: 32236882 PMCID: PMC8637936 DOI: 10.1007/164_2019_298] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Since antiquity, Cannabis has provoked enormous intrigue for its potential medicinal properties as well as for its unique pharmacological effects. The elucidation of its major cannabinoid constituents, Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), led to the synthesis of new cannabinoids (termed synthetic cannabinoids) to understand the mechanisms underlying the pharmacology of Cannabis. These pharmacological tools were instrumental in the ultimate discovery of the endogenous cannabinoid system, which consists of CB1 and CB2 cannabinoid receptors and endogenously produced ligands (endocannabinoids), which bind and activate both cannabinoid receptors. CB1 receptors mediate the cannabimimetic effects of THC and are highly expressed on presynaptic neurons in the nervous system, where they modulate neurotransmitter release. In contrast, CB2 receptors are primarily expressed on immune cells. The endocannabinoids are tightly regulated by biosynthetic and hydrolytic enzymes. Accordingly, the endocannabinoid system plays a modulatory role in many physiological processes, thereby generating many promising therapeutic targets. An unintended consequence of this research was the emergence of synthetic cannabinoids sold for human consumption to circumvent federal laws banning Cannabis use. Here, we describe research that led to the discovery of the endogenous cannabinoid system and show how knowledge of this system benefitted as well as unintentionally harmed human health.
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Affiliation(s)
- Lesley D Schurman
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Dai Lu
- Rangel College of Pharmacy, Health Science Center, Texas A&M University, Kingsville, TX, USA
| | - Debra A Kendall
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT, USA
| | - Allyn C Howlett
- Department of Physiology and Pharmacology and Center for Research on Substance Use and Addiction, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Aron H Lichtman
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA.
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, USA.
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20
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Abstract
Given the aging Baby Boomer generation, changes in cannabis legislation, and the growing acknowledgment of cannabis for its therapeutic potential, it is predicted that cannabis use in the older population will escalate. It is, therefore, important to determine the interaction between the effects of cannabis and aging. The aim of this report is to describe the link between cannabis use and the aging brain. Our review of the literature found few and inconsistent empirical studies that directly address the impact of cannabis use on the aging brain. However, research focused on long-term cannabis use points toward cumulative effects on multimodal systems in the brain that are similarly affected during aging. Specifically, the effects of cannabis and aging converge on overlapping networks in the endocannabinoid, opioid, and dopamine systems that may affect functional decline particularly in the hippocampus and prefrontal cortex, which are critical areas for memory and executive functioning. To conclude, despite the limited current knowledge on the potential interactive effects between cannabis and aging, evidence from the literature suggests that cannabis and aging effects are concurrently present across several neurotransmitter systems. There is a great need for future research to directly test the interactions between cannabis and aging.
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Affiliation(s)
- Hye Bin Yoo
- Center for BrainHealth, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas, USA
| | - Jennifer DiMuzio
- Center for BrainHealth, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas, USA
| | - Francesca M Filbey
- Center for BrainHealth, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas, USA
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ZUBRZYCKI M, STASIOLEK M, ZUBRZYCKA M. Opioid and Endocannabinoid System in Orofacial Pain. Physiol Res 2019; 68:705-715. [DOI: 10.33549/physiolres.934159] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Orofacial pain disorders are frequent in the general population and their pharmacological treatment is difficult and controversial. Therefore, the search for novel, safe and efficient analgesics is an important but still elusive goal for contemporary medicine. In the recent years, the antinociceptive potential of endocannabinoids and opioids has been emphasized. However, concerns for the safety of their use limit their clinical applications. the possibility of modulating the activity of endocannabinoids by regulation of their synthesis and/or degradation offers an innovative approach to the treatment of pain. A rat model of trigeminal pain, utilizing tongue jerks evoked by electrical tooth pulp stimulation during perfusion of the cerebral ventricles with various neurotransmitter solutions can be used in the pharmacological studies of nociception in the orofacial area. The aim of this review is to present the effects of pharmacological activity of opioids and endocannabinoids affecting the transmission of the sensory information from the orofacial area on the example of trigemino-hypoglossal reflex in rats.
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Affiliation(s)
- M. ZUBRZYCKI
- Department of Cardiovascular and Thoracic Surgery, University of Ulm, Ulm, Germany,
| | - M. STASIOLEK
- Department of Neurology, Medical University of Lodz, Lodz, Poland
| | - M. ZUBRZYCKA
- Department of Cardiovascular Physiology, Interdepartmental Chair of Experimental and Clinical Physiology, Medical University of Lodz, Lodz, Poland
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Abstract
Introduction: The opioid epidemic has become an immense problem in North America, and despite decades of research on the most effective means to treat opioid use disorder (OUD), overdose deaths are at an all-time high, and relapse remains pervasive. Discussion: Although there are a number of FDA-approved opioid replacement therapies and maintenance medications to help ease the severity of opioid withdrawal symptoms and aid in relapse prevention, these medications are not risk free nor are they successful for all patients. Furthermore, there are legal and logistical bottlenecks to obtaining traditional opioid replacement therapies such as methadone or buprenorphine, and the demand for these services far outweighs the supply and access. To fill the gap between efficacious OUD treatments and the widespread prevalence of misuse, relapse, and overdose, the development of novel, alternative, or adjunct OUD treatment therapies is highly warranted. In this article, we review emerging evidence that suggests that cannabis may play a role in ameliorating the impact of OUD. Herein, we highlight knowledge gaps and discuss cannabis' potential to prevent opioid misuse (as an analgesic alternative), alleviate opioid withdrawal symptoms, and decrease the likelihood of relapse. Conclusion: The compelling nature of these data and the relative safety profile of cannabis warrant further exploration of cannabis as an adjunct or alternative treatment for OUD.
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Affiliation(s)
- Beth Wiese
- Department of Psychology, University of Missouri–St. Louis, St. Louis, Missouri
- Department of Anesthesiology, Pain Center, Washington University School of Medicine, St. Louis, Missouri
| | - Adrianne R. Wilson-Poe
- Department of Anesthesiology, Pain Center, Washington University School of Medicine, St. Louis, Missouri
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23
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Harris HM, Gul W, ElSohly MA, Sufka KJ. Effects of Cannabidiol and a Novel Cannabidiol Analog against Tactile Allodynia in a Murine Model of Cisplatin-Induced Neuropathy: Enhanced Effects of Sub-Analgesic Doses of Morphine. Med Cannabis Cannabinoids 2018; 1:54-59. [PMID: 34676322 DOI: 10.1159/000489077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 04/10/2018] [Indexed: 11/19/2022] Open
Abstract
Objective This research examined whether a cannabidiol (CBD)-opioid pharmacotherapy could attenuate cisplatin-induced tactile allodynia. Methods Mice (C57BL/6) were given 6 doses of 2.3 mg/kg cisplatin intraperitoneally (IP) on alternating days to induce tactile allodynia as quantified using an electric von Frey (eVF). Test groups in Experiment 1 received either vehicle, 0.1 or 2.5 mg/kg morphine, 1.0 or 2.0 CBD, or the 2 drugs in combination. Test groups in Experiment 2 received either vehicle, 0.1 or 2.5 mg/kg morphine, 1.0, 2.0, 3.0, or 4.0 mg/kg NB2111 (a long-acting CBD analogue), or the 2 drugs in combination. Drugs were administered IP 45 min before eVF assessment. Results Cisplatin produced tactile allodynia that was attenuated by 2.5 mg/kg morphine. Both CBD and NB2111 produced dose-dependent attenuation of tactile allodynia. CBD and NB2111, given in combination with sub-analgesic doses of morphine, produced attenuation of tactile allodynia equivalent to 2.5 mg/kg morphine. Conclusions While both CBD and NB2111, either alone or in combination with sub-analgesic doses of opioids, exhibited analgesic effects, NB2111 could be capable of superior analgesia over time by virtue of enhanced pharmacokinetics.
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Affiliation(s)
- Hannah Marie Harris
- Department of Psychology, University of Mississippi, Oxford, Mississippi, USA
| | - Waseem Gul
- National Center for Natural Products Research, University of Mississippi, Oxford, Mississippi, USA
| | - Mahmoud A ElSohly
- National Center for Natural Products Research, University of Mississippi, Oxford, Mississippi, USA.,Department of BioMolecular Sciences, University of Mississippi, Oxford, Mississippi, USA
| | - Kenneth J Sufka
- Department of Psychology, University of Mississippi, Oxford, Mississippi, USA.,National Center for Natural Products Research, University of Mississippi, Oxford, Mississippi, USA
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24
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Dubový P, Klusáková I, Hradilová-Svíženská I, Joukal M, Boadas-Vaello P. Activation of Astrocytes and Microglial Cells and CCL2/CCR2 Upregulation in the Dorsolateral and Ventrolateral Nuclei of Periaqueductal Gray and Rostral Ventromedial Medulla Following Different Types of Sciatic Nerve Injury. Front Cell Neurosci 2018; 12:40. [PMID: 29515373 PMCID: PMC5825898 DOI: 10.3389/fncel.2018.00040] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 02/01/2018] [Indexed: 12/18/2022] Open
Abstract
Peripheral nerve injuries (PNIs) may result in cellular and molecular changes in supraspinal structures possibly involved in neuropathic pain (NPP) maintenance. Activated glial cells in specific supraspinal subregions may affect the facilitatory role of descending pathways. Sterile chronic compression injury (sCCI) and complete sciatic nerve transection (CSNT) in rats were used as NPP models to study the activation of glial cells in the subregions of periaqueductal gray (PAG) and rostral ventromedial medulla (RVM). Molecular markers for activated astrocytes (glial fibrillary acidic protein, GFAP) and microglial cells (OX42) were assessed by quantitative immunohistochemistry and western blotting. The cellular distribution of CCL2/CCR2 was monitored using immunofluorescence. sCCI induced both mechanical and thermal hypersensitivity from day 1 up to 3 weeks post-injury. Unilateral sCCI or CSNT for 3 weeks induced significant activation of astrocytes bilaterally in both dorsolateral (dlPAG) and ventrolateral PAG (vlPAG) compared to naïve or sham-operated rats. More extensive astrocyte activation by CSNT compared to sCCI was induced bilaterally in dlPAG and ipsilaterally in vlPAG. Significantly more extensive activation of astrocytes was also found in RVM after CSNT than sCCI. The CD11b immunopositive region, indicating activated microglial cells, was remarkably larger in dlPAG and vlPAG of both sides from sCCI- and CSNT-operated rats compared to naïve or sham-operated controls. No significant differences in microglial activation were detected in dlPAG or vlPAG after CSNT compared to sCCI. Both nerve injury models induced no significant differences in microglial activation in the RVM. Neurons and activated GFAP+ astrocytes displayed CCL2-immunoreaction, while activated OX42+ microglial cells were CCR2-immunopositive in both PAG and RVM after sCCI and CSNT. Overall, while CSNT induced robust astrogliosis in both PAG and RVM, microglial cell activation was similar in the supraspinal structures in both injury nerve models. Activated astrocytes in PAG and RVM may sustain facilitation of the descending system maintaining NPP, while microglial activation may be associated with a reaction to long-lasting peripheral injury. Microglial activation via CCR2 may be due to neuronal and astrocytal release of CCL2 in PAG and RVM following injury.
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Affiliation(s)
- Petr Dubový
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Ilona Klusáková
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Ivana Hradilová-Svíženská
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Marek Joukal
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Pere Boadas-Vaello
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Brno, Czechia
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Universitat de Girona, Girona, Spain
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Schafer SM, Geuter S, Wager TD. Mechanisms of placebo analgesia: A dual-process model informed by insights from cross-species comparisons. Prog Neurobiol 2018; 160:101-122. [PMID: 29108801 PMCID: PMC5747994 DOI: 10.1016/j.pneurobio.2017.10.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 10/24/2017] [Accepted: 10/28/2017] [Indexed: 12/19/2022]
Abstract
Placebo treatments are pharmacologically inert, but are known to alleviate symptoms across a variety of clinical conditions. Associative learning and cognitive expectations both play important roles in placebo responses, however we are just beginning to understand how interactions between these processes lead to powerful effects. Here, we review the psychological principles underlying placebo effects and our current understanding of their brain bases, focusing on studies demonstrating both the importance of cognitive expectations and those that demonstrate expectancy-independent associative learning. To account for both forms of placebo analgesia, we propose a dual-process model in which flexible, contextually driven cognitive schemas and attributions guide associative learning processes that produce stable, long-term placebo effects. According to this model, the placebo-induction paradigms with the most powerful effects are those that combine reinforcement (e.g., the experience of reduced pain after placebo treatment) with suggestions and context cues that disambiguate learning by attributing perceived benefit to the placebo. Using this model as a conceptual scaffold, we review and compare neurobiological systems identified in both human studies of placebo analgesia and behavioral pain modulation in rodents. We identify substantial overlap between the circuits involved in human placebo analgesia and those that mediate multiple forms of context-based modulation of pain behavior in rodents, including forebrain-brainstem pathways and opioid and cannabinoid systems in particular. This overlap suggests that placebo effects are part of a set of adaptive mechanisms for shaping nociceptive signaling based on its information value and anticipated optimal response in a given behavioral context.
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Affiliation(s)
- Scott M Schafer
- Department of Psychology and Neuroscience, University of Colorado, 345 UCB, Boulder, CO 80309, USA
| | - Stephan Geuter
- Department of Psychology and Neuroscience, University of Colorado, 345 UCB, Boulder, CO 80309, USA; Institute of Cognitive Science, University of Colorado Boulder, 344 UCB, Boulder, CO 80309, USA; Department of Biostatistics, Johns Hopkins University, 615 N Wolfe St, Baltimore, MD 21205, USA
| | - Tor D Wager
- Department of Psychology and Neuroscience, University of Colorado, 345 UCB, Boulder, CO 80309, USA; Institute of Cognitive Science, University of Colorado Boulder, 344 UCB, Boulder, CO 80309, USA.
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26
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Donvito G, Nass SR, Wilkerson JL, Curry ZA, Schurman LD, Kinsey SG, Lichtman AH. The Endogenous Cannabinoid System: A Budding Source of Targets for Treating Inflammatory and Neuropathic Pain. Neuropsychopharmacology 2018; 43:52-79. [PMID: 28857069 PMCID: PMC5719110 DOI: 10.1038/npp.2017.204] [Citation(s) in RCA: 181] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 08/24/2017] [Accepted: 08/27/2017] [Indexed: 02/07/2023]
Abstract
A great need exists for the development of new medications to treat pain resulting from various disease states and types of injury. Given that the endogenous cannabinoid (that is, endocannabinoid) system modulates neuronal and immune cell function, both of which play key roles in pain, therapeutics targeting this system hold promise as novel analgesics. Potential therapeutic targets include the cannabinoid receptors, type 1 and 2, as well as biosynthetic and catabolic enzymes of the endocannabinoids N-arachidonoylethanolamine and 2-arachidonoylglycerol. Notably, cannabinoid receptor agonists as well as inhibitors of endocannabinoid-regulating enzymes fatty acid amide hydrolase and monoacylglycerol lipase produce reliable antinociceptive effects, and offer opioid-sparing antinociceptive effects in myriad preclinical inflammatory and neuropathic pain models. Emerging clinical studies show that 'medicinal' cannabis or cannabinoid-based medications relieve pain in human diseases such as cancer, multiple sclerosis, and fibromyalgia. However, clinical data have yet to demonstrate the analgesic efficacy of inhibitors of endocannabinoid-regulating enzymes. Likewise, the question of whether pharmacotherapies aimed at the endocannabinoid system promote opioid-sparing effects in the treatment of pain reflects an important area of research. Here we examine the preclinical and clinical evidence of various endocannabinoid system targets as potential therapeutic strategies for inflammatory and neuropathic pain conditions.
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Affiliation(s)
- Giulia Donvito
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA, USA
| | - Sara R Nass
- Department of Psychology, West Virginia University, Morgantown, WV, USA
| | - Jenny L Wilkerson
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA, USA
| | - Zachary A Curry
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA, USA
| | - Lesley D Schurman
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA, USA
| | - Steven G Kinsey
- Department of Psychology, West Virginia University, Morgantown, WV, USA
| | - Aron H Lichtman
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA, USA
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27
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Zubrzycki M, Janecka A, Liebold A, Ziegler M, Zubrzycka M. Effects of centrally administered endocannabinoids and opioids on orofacial pain perception in rats. Br J Pharmacol 2017; 174:3780-3789. [PMID: 28771697 DOI: 10.1111/bph.13970] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 07/12/2017] [Accepted: 07/27/2017] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND AND PURPOSE Endocannabinoids and opioids play a vital role in mediating pain-induced analgesia. The specific effects of these compounds within the orofacial region are largely unknown. In this study, we tried to determine whether an increase in cannabinoid and opioid concentration in the CSF affects impulse transmission between the motor centres localized in the vicinity of the third and fourth cerebral ventricles. EXPERIMENTAL APPROACH The study objectives were realized on rats using a method that allows the recording of the amplitude of evoked tongue jerks (ETJ) in response to noxious tooth pulp stimulation. The amplitude of ETJ was a measure of the effect of neurotransmitters on neural structures. KEY RESULTS Perfusion of cerebral ventricles with anandamide (AEA), endomorphin-2 (EM-2), URB597, an inhibitor of fatty acid amide hydrolase (FAAH) and JZL195, a dual inhibitor of FAAH and monoacylglycerol lipase (MAGL) reduced the ETJ amplitude. The antinociceptive effect of AEA, EM-2, URB597 and JZL195 was blocked by CB1 receptor antagonist, AM251 and by μ receptor-antagonist, β-funaltrexamine. In contrast to AEA, 2-arachidonoylglycerol alone did not decrease ETJ amplitude. CONCLUSIONS AND IMPLICATIONS We demonstrated that in the orofacial area, analgesic activity is modulated by AEA and that EM-2-induced antinociception was mediated by μ and CB1 receptors. The action of AEA and EM-2 is tightly regulated by FAAH and FAAH/MAGL, by preventing the breakdown of endogenous cannabinoids in regions where they are produced on demand. Therefore, the current findings support the therapeutic potential of FAAH and FAAH/MAGL inhibitors as novel pharmacotherapeutic agents for orofacial pain.
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Affiliation(s)
- Marek Zubrzycki
- Department of Cardiovascular and Thoracic Surgery, University of Ulm, Ulm, Germany
| | - Anna Janecka
- Department of Biomolecular Chemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - Andreas Liebold
- Department of Cardiovascular and Thoracic Surgery, University of Ulm, Ulm, Germany
| | - Mechthild Ziegler
- Department of Cardiac Anesthesiology, University Hospital Ulm, Ulm, Germany
| | - Maria Zubrzycka
- Department of Cardiovascular Physiology, Interdepartmental Chair of Experimental and Clinical Physiology, Medical University of Lodz, Lodz, Poland
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Starowicz K, Finn DP. Cannabinoids and Pain: Sites and Mechanisms of Action. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2017; 80:437-475. [PMID: 28826543 DOI: 10.1016/bs.apha.2017.05.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The endocannabinoid system, consisting of the cannabinoid1 receptor (CB1R) and cannabinoid2 receptor (CB2R), endogenous cannabinoid ligands (endocannabinoids), and metabolizing enzymes, is present throughout the pain pathways. Endocannabinoids, phytocannabinoids, and synthetic cannabinoid receptor agonists have antinociceptive effects in animal models of acute, inflammatory, and neuropathic pain. CB1R and CB2R located at peripheral, spinal, or supraspinal sites are important targets mediating these antinociceptive effects. The mechanisms underlying the analgesic effects of cannabinoids likely include inhibition of presynaptic neurotransmitter and neuropeptide release, modulation of postsynaptic neuronal excitability, activation of the descending inhibitory pain pathway, and reductions in neuroinflammatory signaling. Strategies to dissociate the psychoactive effects of cannabinoids from their analgesic effects have focused on peripherally restricted CB1R agonists, CB2R agonists, inhibitors of endocannabinoid catabolism or uptake, and modulation of other non-CB1R/non-CB2R targets of cannabinoids including TRPV1, GPR55, and PPARs. The large body of preclinical evidence in support of cannabinoids as potential analgesic agents is supported by clinical studies demonstrating their efficacy across a variety of pain disorders.
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Affiliation(s)
- Katarzyna Starowicz
- Institute of Pharmacology, Polish Academy of Sciences, Laboratory of Pain Pathophysiology, Krakow, Poland
| | - David P Finn
- Pharmacology and Therapeutics, School of Medicine, Galway Neuroscience Centre and Centre for Pain Research, NCBES, National University of Ireland, Galway, Ireland.
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29
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Nessren MAER, Omyma GA, Ebtihal AAEA, Ayman MO, Amel T. Oxytocin ameliorates the deleterious effect of pain in adult male rats. JOURNAL OF PHYSIOLOGY AND PATHOPHYSIOLOGY 2017; 8:1-6. [DOI: 10.5897/jpap2016.0107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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30
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Wilkerson JL, Ghosh S, Mustafa M, Abdullah RA, Niphakis MJ, Cabrera R, Maldonado RL, Cravatt BF, Lichtman AH. The endocannabinoid hydrolysis inhibitor SA-57: Intrinsic antinociceptive effects, augmented morphine-induced antinociception, and attenuated heroin seeking behavior in mice. Neuropharmacology 2016; 114:156-167. [PMID: 27890602 DOI: 10.1016/j.neuropharm.2016.11.015] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 10/11/2016] [Accepted: 11/21/2016] [Indexed: 12/18/2022]
Abstract
Although opioids are highly efficacious analgesics, their abuse potential and other untoward side effects diminish their therapeutic utility. The addition of non-opioid analgesics offers a promising strategy to reduce required antinociceptive opioid doses that concomitantly reduce opioid-related side effects. Inhibitors of the primary endocannabinoid catabolic enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) show opioid-sparing effects in preclinical models of pain. As simultaneous inhibition of these enzymes elicits enhanced antinociceptive effects compared with single enzyme inhibition, the present study tested whether the dual FAAH-MAGL inhibitor SA-57 [4-[2-(4-chlorophenyl)ethyl]-1-piperidinecarboxylic acid 2-(methylamino)-2-oxoethyl ester] produces morphine-sparing antinociceptive effects, without major side effects associated with either drug class. SA-57 dose-dependently reversed mechanical allodynia in the constriction injury (CCI) of the sciatic nerve model of neuropathic pain and carrageenan inflammatory pain model. As previously reported, SA-57 was considerably more potent in elevating anandamide (AEA) than 2-arachidonyl glycerol (2-AG) in brain. Its anti-allodynic effects required cannabinoid (CB)1 and CB2 receptors; however, only CB2 receptors were necessary for the anti-edematous effects in the carrageenan assay. Although high doses of SA-57 alone were required to produce antinociception, low doses of this compound, which elevated AEA and did not affect 2-AG brain levels, augmented the antinociceptive effects of morphine, but lacked cannabimimetic side effects. Because of the high abuse liability of opioids and implication of the endocannabinoid system in the reinforcing effects of opioids, the final experiment tested whether SA-57 would alter heroin seeking behavior. Strikingly, SA-57 reduced heroin-reinforced nose poke behavior and the progressive ratio break point for heroin. In conclusion, the results of the present study suggest that inhibition of endocannabinoid degradative enzymes represents a promising therapeutic approach to decrease effective doses of opioids needed for clinical pain control, and may also possess therapeutic potential to reduce opioid abuse.
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Affiliation(s)
- Jenny L Wilkerson
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA.
| | - Sudeshna Ghosh
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Mohammed Mustafa
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Rehab A Abdullah
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Micah J Niphakis
- The Skaggs Institute for Chemical Biology and Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Roberto Cabrera
- Laboratory of Neuropharmacology. Department de Ciencies Experimentals i de la Salut, Pompeu Fabra University, PRBB, C/ Doctor Aiguader 88, 08003 Barcelona, Spain
| | - Rafael L Maldonado
- Laboratory of Neuropharmacology. Department de Ciencies Experimentals i de la Salut, Pompeu Fabra University, PRBB, C/ Doctor Aiguader 88, 08003 Barcelona, Spain
| | - Benjamin F Cravatt
- The Skaggs Institute for Chemical Biology and Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Aron H Lichtman
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
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31
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Auh QS, Chun YH, Melemedjian OK, Zhang Y, Ro JY. Peripheral interactions between cannabinoid and opioid receptor agonists in a model of inflammatory mechanical hyperalgesia. Brain Res Bull 2016; 125:211-7. [PMID: 27450703 DOI: 10.1016/j.brainresbull.2016.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 01/28/2023]
Abstract
Activation of opioid and cannabinoid receptors expressed in nociceptors induces effective antihyperalgesia. In this study, we examined whether combinations of opioid and cannabinoid receptor agonists directed at the injured site would enhance therapeutic effectiveness. Behavioral pharmacology experiments were performed to compare the effects of DAMGO, a selective agonist for μ-opioid receptor (MOR), ACPA, a specific agonist for CB1, and combinations of DAMGO and ACPA in attenuating complete Freund's adjuvant (CFA)-induced mechanical hyperalgesia in the rat hindpaw. DAMGO (1μg-1mg) or ACPA (1μg-2mg) was administered into the inflamed paw when mechanical hyperalgesia was fully developed. When administered individually, DAMGO and ACPA dose-dependently reversed the mechanical hyperalgesia. DAMGO displayed a lower ED50 value (57.4±2.49μg) than ACPA (111.6±2.18μg), but ACPA produced longer lasting antihyperalgesic effects. Combinations of DAMGO and ACPA also dose-dependently attenuated mechanical hyperalgesia, but the antihyperalgesic effects were partial and transient even at high doses. Using isobolographic analysis, we determined that combined treatment with DAMGO and ACPA produced antagonistic effects with the observed ED50 of 128.4±2.28μg. Our findings showed that MOR and CB1 agonists directed at the inflamed site effectively attenuate mechanical hyperalgesia when administered individually, but exert opposing effects when administered together. The antagonistic interactions between the two classes of drugs at the inflamed site suggest distinct mechanisms unique to peripheral nociceptors or inflamed tissue, and therefore require further studies to investigate whether the therapeutic utility of the combined drug treatments in chronic pain conditions can be optimized.
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Affiliation(s)
- Q-Schick Auh
- Kyung Hee University, School of Dentistry, Department of Oral Medicine, 1 Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea
| | - Yang Hyun Chun
- Kyung Hee University, School of Dentistry, Department of Oral Medicine, 1 Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea
| | - Ohannes K Melemedjian
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St., Baltimore, MD 21201, USA
| | - Youping Zhang
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St., Baltimore, MD 21201, USA
| | - Jin Y Ro
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St., Baltimore, MD 21201, USA; Kyung Hee University, School of Dentistry, Department of Oral Medicine, 1 Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea.
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32
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Fitzgibbon M, Finn DP, Roche M. High Times for Painful Blues: The Endocannabinoid System in Pain-Depression Comorbidity. Int J Neuropsychopharmacol 2015; 19:pyv095. [PMID: 26342110 PMCID: PMC4815466 DOI: 10.1093/ijnp/pyv095] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/17/2015] [Indexed: 01/06/2023] Open
Abstract
Depression and pain are two of the most debilitating disorders worldwide and have an estimated cooccurrence of up to 80%. Comorbidity of these disorders is more difficult to treat, associated with significant disability and impaired health-related quality of life than either condition alone, resulting in enormous social and economic cost. Several neural substrates have been identified as potential mediators in the association between depression and pain, including neuroanatomical reorganization, monoamine and neurotrophin depletion, dysregulation of the hypothalamo-pituitary-adrenal axis, and neuroinflammation. However, the past decade has seen mounting evidence supporting a role for the endogenous cannabinoid (endocannabinoid) system in affective and nociceptive processing, and thus, alterations in this system may play a key role in reciprocal interactions between depression and pain. This review will provide an overview of the preclinical evidence supporting an interaction between depression and pain and the evidence supporting a role for the endocannabinoid system in this interaction.
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Affiliation(s)
| | | | - Michelle Roche
- Physiology (Ms Fitzgibbon and Dr Roche), and Pharmacology and Therapeutics (Dr Finn), School of Medicine, Galway Neuroscience Centre and Centre for Pain Research (Ms Fitzgibbon, Dr Finn, and Dr Roche), National Centre for Biomedical Engineering Science, National University of Ireland Galway, Ireland.
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Mascarenhas DC, Gomes KS, Nunes-de-Souza RL. Role of TRPV1 channels of the dorsal periaqueductal gray in the modulation of nociception and open elevated plus maze-induced antinociception in mice. Behav Brain Res 2015; 292:547-54. [PMID: 26183651 DOI: 10.1016/j.bbr.2015.07.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 07/02/2015] [Accepted: 07/06/2015] [Indexed: 12/19/2022]
Abstract
Recent findings have identified the presence of transient receptor potential vanilloid-1 (TRPV1) channels within the dorsal portion of the periaqueductal gray (dPAG), suggesting their involvement in the control of pain and environmentally-induced antinociception. Environmentally, antinociception may be achieved through the use of an open elevated plus maze (oEPM, an EPM with 4 open arms), a highly aversive environmental situation. Here, we investigated the role of these TRPV1 channels within the dPAG in the modulation of a tonic pain and in the oEPM-induced antinociception. Male Swiss mice, under the nociceptive effect of 2.5% formalin injected into the right hind paw, received intra-dPAG injections of the TRPV1 agonist (capsaicin: 0, 0.01, 0.1 or 1.0 nmol/0.2 μL; Experiment 1) or antagonist (capsazepine: 0, 10 or 30 nmol/0.2 μL; Experiment 2) or combined injections of capsazepine (30 nmol) and capsaicin (1.0 nmol) (Experiment 3) and the time spent licking the formalin-injected paw was recorded. In Experiment 4, mice received intra-dPAG capsazepine (0 or 30 nmol) and were exposed to the oEPM or to a control situation, an enclosed EPM (eEPM; an EPM with 4 enclosed arms). Results showed that while capsaicin (1 nmol) decreased the time spent licking the formalin-injected paw, capsazepine did not change nociceptive response. Capsazepine (30 nmol) blocked pain inhibition induced by capsaicin and mildly attenuated the oEPM-induced antinociception. Our results revealed an important role of TRPV1 channels within the dPAG in the modulation of pain and in the phenomenon known as fear-induced antinociception in mice.
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Affiliation(s)
- Diego Cardozo Mascarenhas
- Joint Graduate Program in Physiological Sciences, UFSCar/UNESP-São Carlos, SP, 13565-905, Brazil; School of Pharmaceutical Sciences, Universidade Estadual Paulista-UNESP, 14801-902, Araraquara, SP, Brazil
| | - Karina Santos Gomes
- School of Pharmaceutical Sciences, Universidade Estadual Paulista-UNESP, 14801-902, Araraquara, SP, Brazil
| | - Ricardo Luiz Nunes-de-Souza
- Joint Graduate Program in Physiological Sciences, UFSCar/UNESP-São Carlos, SP, 13565-905, Brazil; School of Pharmaceutical Sciences, Universidade Estadual Paulista-UNESP, 14801-902, Araraquara, SP, Brazil.
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Corcoran L, Roche M, Finn DP. The Role of the Brain's Endocannabinoid System in Pain and Its Modulation by Stress. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 125:203-55. [DOI: 10.1016/bs.irn.2015.10.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Abstract
This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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Wilson-Poe AR, Lau BK, Vaughan CW. Repeated morphine treatment alters cannabinoid modulation of GABAergic synaptic transmission within the rat periaqueductal grey. Br J Pharmacol 2014; 172:681-90. [PMID: 24916363 DOI: 10.1111/bph.12809] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 05/29/2014] [Accepted: 06/05/2014] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Cannabinoids and opioids produce antinociception by modulating GABAergic synaptic transmission in a descending analgesic pathway from the midbrain periaqueductal grey (PAG). While chronic opioid treatment produces opioid tolerance, it has recently been shown to enhance cannabinoid-induced antinociception within the PAG. This study examined the effect of repeated opioid treatment on opioid and cannabinoid presynaptic modulation of GABAergic synaptic transmission in PAG. EXPERIMENTAL APPROACH Midbrain PAG slices were prepared from untreated rats, and rats that had undergone repeated morphine or saline pretreatment. Whole-cell voltage-clamp recordings were made from neurons within the ventrolateral PAG. KEY RESULTS In slices from untreated animals, the cannabinoid receptor agonist WIN55212 and the μ receptor agonist DAMGO inhibited electrically evoked GABAA receptor-mediated inhibitory postsynaptic currents (IPSCs) IPSCs in PAG neurons, with IC50 s of 30 and 100 nM respectively. The inhibition of evoked IPSCs produced by WIN55212 (30 nM) and DAMGO (100 nM) was similar in PAG neurons from morphine- and saline-treated animals. The cannabinoid CB1 receptor antagonist AM251 increased the frequency of spontaneous miniature IPSCs in PAG neurons from repeated morphine-, but not saline-treated animals. DAMGO inhibition of evoked IPSCs was enhanced in the presence of AM251 in morphine-, but not saline-treated animals. CONCLUSIONS AND IMPLICATIONS These results indicate that the efficiency of agonist-induced inhibition of GABAergic synaptic transmission is enhanced by morphine treatment, although this is dampened by endocannabinoid-mediated tonic inhibition. Thus, endocannabinoid modulation of synaptic transmission could provide an alternative analgesic approach in a morphine-tolerant state. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- A R Wilson-Poe
- Pain Management Research Institute, Kolling Institute for Medical Research, Northern Clinical School, The University of Sydney, St Leonards, NSW, Australia
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Siqueira-Lima PS, Araújo AAS, Lucchese AM, Quintans JSS, Menezes PP, Alves PB, de Lucca Júnior W, Santos MRV, Bonjardim LR, Quintans-Júnior LJ. β-cyclodextrin complex containing Lippia grata leaf essential oil reduces orofacial nociception in mice - evidence of possible involvement of descending inhibitory pain modulation pathway. Basic Clin Pharmacol Toxicol 2013; 114:188-96. [PMID: 24119304 DOI: 10.1111/bcpt.12145] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 09/01/2013] [Indexed: 12/01/2022]
Abstract
The treatment of orofacial pain remains a major challenge for modern medicine. Thus, we prepared and physicochemically characterized a new β-cyclodextrin complex containing Lippia grata leaf essential oil (β-CD/EO) to investigate their possible antinociceptive activity in animal models of orofacial pain. The results of Differential scanning calorimeter (DSC) and Thermogravimetry/derivative thermogravimetry (TG/DTG) showed that the products prepared by Slurry complexation (SC) method were able to incorporate greater amounts of EO. In the X-ray diffractogram, it was shown that complex between EO and β-CD was formed. Male Swiss mice were pre-treated with β-CD/EO (6, 12 or 24 mg/kg, per os, gavage, p.o.), morphine (5 mg/kg, i.p.) or vehicle (distilled water, p.o.) 1 hr before treatment with formalin (20 μL, 2%), capsaicin (20 μL, 2.5 μg) or glutamate (40 μL, 25 μM) into the right upper lip. Our results demonstrated that p.o. treatment with β-CD/EO was significantly (p < 0.05 or p < 0.001) capable of reducing the nociceptive face-rubbing behaviour in both phases of the formalin test. β-CD/EO-treated mice were also significantly (p < 0.05 or p < 0.001) protected against nociception induced by capsaicin and glutamate. For the action in the central nervous system (CNS), ninety minutes after the treatment, the mice were perfused, the brains collected, crioprotected, cut in a criostate and submitted to an immunofluorescence protocol for Fos protein. The immunofluorescence protocol demonstrated that the β-CD/EO significantly activated (p < 0.05; p < 0.01 or p < 0.001) the motor cortex, the Locus ceruleus, the nucleus raphe magnus and the periaqueductal gray of the CNS. These effects apparently did not alter, in tested doses, the motor coordination of mice in the rota-rod test. Our results proposed that β-CD/EO might present an important draft of drug to the study of new compounds for the treatment of orofacial pain.
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Affiliation(s)
- Pollyana S Siqueira-Lima
- Biotechnology Graduate Program, The State University of Feira de Santana, Feira de Santana, BA, Brazil; Department of Pharmacy, Federal University of Sergipe, Aracaju, SE, Brazil
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