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Singh S, Sarroza D, English A, Whittington D, Dong A, Malamas M, Makriyannis A, van der Stelt M, Li Y, Zweifel L, Bruchas MR, Land BB, Stella N. P2X 7 receptor-dependent increase in endocannabinoid 2-arachidonoyl glycerol production by neuronal cells in culture: Dynamics and mechanism. Br J Pharmacol 2024; 181:2459-2477. [PMID: 38581262 DOI: 10.1111/bph.16348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 01/12/2024] [Accepted: 02/01/2024] [Indexed: 04/08/2024] Open
Abstract
BACKGROUND AND PURPOSE Neurotransmission and neuroinflammation are controlled by local increases in both extracellular ATP and the endocannabinoid 2-arachidonoyl glycerol (2-AG). While it is known that extracellular ATP stimulates 2-AG production in cells in culture, the dynamics and molecular mechanisms that underlie this response remain poorly understood. Detection of real-time changes in eCB levels with the genetically encoded sensor, GRABeCB2.0, can address this shortfall. EXPERIMENTAL APPROACH 2-AG and arachidonoylethanolamide (AEA) levels in Neuro2a (N2a) cells were measured by LC-MS, and GRABeCB2.0 fluorescence changes were detected using live-cell confocal microscopy and a 96-well fluorescence plate reader. KEY RESULTS 2-AG and AEA increased GRABeCB2.0 fluorescence in N2a cells with EC50 values of 81 and 58 nM, respectively; both responses were reduced by the cannabinoid receptor type 1 (CB1R) antagonist SR141617 and absent in cells expressing the mutant-GRABeCB2.0. ATP increased only 2-AG levels in N2a cells, as measured by LC-MS, and induced a transient increase in the GRABeCB2.0 signal within minutes primarily via activation of P2X7 receptors (P2X7R). This response was dependent on diacylglycerol lipase β activity, partially dependent on extracellular calcium and phospholipase C activity, but not controlled by the 2-AG hydrolysing enzyme, α/β-hydrolase domain containing 6 (ABHD6). CONCLUSIONS AND IMPLICATIONS Considering that P2X7R activation increases 2-AG levels within minutes, our results show how these molecular components are mechanistically linked. The specific molecular components in these signalling systems represent potential therapeutic targets for the treatment of neurological diseases, such as chronic pain, that involve dysregulated neurotransmission and neuroinflammation.
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Affiliation(s)
- Simar Singh
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
| | - Dennis Sarroza
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
| | - Anthony English
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
| | - Dale Whittington
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Ao Dong
- Peking University School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Michael Malamas
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, USA
| | - Alexandros Makriyannis
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, USA
| | | | - Yulong Li
- Peking University School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Larry Zweifel
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
- Center for Cannabis Research, University of Washington, Seattle, Washington, USA
- Center for the Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, Washington, USA
| | - Michael R Bruchas
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
- Center for Cannabis Research, University of Washington, Seattle, Washington, USA
- Center for the Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, Washington, USA
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington, USA
| | - Benjamin B Land
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
- Center for Cannabis Research, University of Washington, Seattle, Washington, USA
- Center for the Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, Washington, USA
| | - Nephi Stella
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
- Center for Cannabis Research, University of Washington, Seattle, Washington, USA
- Center for the Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, Washington, USA
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Kerr PL, Gregg JM. The Roles of Endogenous Opioids in Placebo and Nocebo Effects: From Pain to Performance to Prozac. ADVANCES IN NEUROBIOLOGY 2024; 35:183-220. [PMID: 38874724 DOI: 10.1007/978-3-031-45493-6_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2024]
Abstract
Placebo and nocebo effects have been well documented for nearly two centuries. However, research has only relatively recently begun to explicate the neurobiological underpinnings of these phenomena. Similarly, research on the broader social implications of placebo/nocebo effects, especially within healthcare delivery settings, is in a nascent stage. Biological and psychosocial outcomes of placebo/nocebo effects are of equal relevance. A common pathway for such outcomes is the endogenous opioid system. This chapter describes the history of placebo/nocebo in medicine; delineates the current state of the literature related to placebo/nocebo in relation to pain modulation; summarizes research findings related to human performance in sports and exercise; discusses the implications of placebo/nocebo effects among diverse patient populations; and describes placebo/nocebo influences in research related to psychopharmacology, including the relevance of endogenous opioids to new lines of research on antidepressant pharmacotherapies.
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Affiliation(s)
- Patrick L Kerr
- West Virginia University School of Medicine-Charleston, Charleston, WV, USA.
| | - John M Gregg
- Department of Surgery, VTCSOM, Blacksburg, VA, USA
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Demartini C, Greco R, Zanaboni AM, Francavilla M, Facchetti S, Tassorelli C. URB937 Prevents the Development of Mechanical Allodynia in Male Rats with Trigeminal Neuralgia. Pharmaceuticals (Basel) 2023; 16:1626. [PMID: 38004491 PMCID: PMC10675761 DOI: 10.3390/ph16111626] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/03/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
Cannabinoids are proposed for alleviating neuropathic pain, but their use is limited by cannabimimetic side effects. The inhibition of the fatty acid amide hydrolase (FAAH), the degrading enzyme of the endocannabinoid anandamide, has received attention as an alternative to cannabinoids in the treatment of neuropathic pain. Here, we investigated the effect of URB937, a blood-brain barrier impermeant FAAH inhibitor, on experimentally induced mechanical allodynia in an animal model of trigeminal neuralgia. Male Sprague-Dawley rats were subjected to chronic constriction injury of the infraorbital nerve (IoN-CCI); operated animals were treated sub-chronically with URB937 (1 mg/kg, i.p.) or vehicle before or after trigeminal mechanical allodynia establishment. We also assayed mRNA expression levels of the pain neuropeptide calcitonin gene-related peptide (CGRP) and cytokines in the medulla, cervical spinal cord, and trigeminal ganglion ipsilateral to IoN-CCI using rt-PCR. URB937 treatment prevented the development of mechanical allodynia and IoN-CCI-induced changes in mRNA expression levels of CGRP and cytokines in the evaluated areas. When administered after allodynia development, URB937 prevented IoN-CCI-induced changes in CGRP and cytokine gene expression; this was not associated with a significant abrogation of the mechanical allodynia. These findings suggest that URB937 may counteract, but not reverse, the development of allodynia in trigeminal neuralgia. Further research is needed to elucidate the underlying mechanisms.
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Affiliation(s)
- Chiara Demartini
- Department of Brain and Behavioral Sciences, University of Pavia, Via Bassi 21, 27100 Pavia, Italy; (A.M.Z.); (M.F.); (C.T.)
- Section of Translational Neurovascular Research, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (R.G.); (S.F.)
| | - Rosaria Greco
- Section of Translational Neurovascular Research, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (R.G.); (S.F.)
| | - Anna Maria Zanaboni
- Department of Brain and Behavioral Sciences, University of Pavia, Via Bassi 21, 27100 Pavia, Italy; (A.M.Z.); (M.F.); (C.T.)
- Section of Translational Neurovascular Research, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (R.G.); (S.F.)
| | - Miriam Francavilla
- Department of Brain and Behavioral Sciences, University of Pavia, Via Bassi 21, 27100 Pavia, Italy; (A.M.Z.); (M.F.); (C.T.)
- Section of Translational Neurovascular Research, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (R.G.); (S.F.)
| | - Sara Facchetti
- Section of Translational Neurovascular Research, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (R.G.); (S.F.)
| | - Cristina Tassorelli
- Department of Brain and Behavioral Sciences, University of Pavia, Via Bassi 21, 27100 Pavia, Italy; (A.M.Z.); (M.F.); (C.T.)
- Section of Translational Neurovascular Research, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (R.G.); (S.F.)
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Piscura MK, Henderson-Redmond AN, Barnes RC, Mitra S, Guindon J, Morgan DJ. Mechanisms of cannabinoid tolerance. Biochem Pharmacol 2023; 214:115665. [PMID: 37348821 PMCID: PMC10528043 DOI: 10.1016/j.bcp.2023.115665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/09/2023] [Accepted: 06/13/2023] [Indexed: 06/24/2023]
Abstract
Cannabis has been used recreationally and medically for centuries, yet research into understanding the mechanisms of its therapeutic effects has only recently garnered more attention. There is evidence to support the use of cannabinoids for the treatment of chronic pain, muscle spasticity, nausea and vomiting due to chemotherapy, improving weight gain in HIV-related cachexia, emesis, sleep disorders, managing symptoms in Tourette syndrome, and patient-reported muscle spasticity from multiple sclerosis. However, tolerance and the risk for cannabis use disorder are two significant disadvantages for cannabinoid-based therapies in humans. Recent work has revealed prominent sex differences in the acute response and tolerance to cannabinoids in both humans and animal models. This review will discuss evidence demonstrating cannabinoid tolerance in rodents, non-human primates, and humans and our current understanding of the neuroadaptations occurring at the cannabinoid type 1 receptor (CB1R) that are responsible tolerance. CB1R expression is downregulated in tolerant animals and humans while there is strong evidence of CB1R desensitization in cannabinoid tolerant rodent models. Throughout the review, critical knowledge gaps are indicated and discussed, such as the lack of a neuroimaging probe to assess CB1R desensitization in humans. The review discusses the intracellular signaling pathways that are responsible for mediating CB1R desensitization and downregulation including the action of G protein-coupled receptor kinases, β-arrestin2 recruitment, c-Jun N-terminal kinases, protein kinase A, and the intracellular trafficking of CB1R. Finally, the review discusses approaches to reduce cannabinoid tolerance in humans based on our current understanding of the neuroadaptations and mechanisms responsible for this process.
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Affiliation(s)
- Mary K Piscura
- Department of Biomedical Sciences, Marshall University, Huntington, WV 25755, USA; Department of Biomedical Sciences, Edward Via College of Osteopathic Medicine, Auburn, AL 36832, USA
| | | | - Robert C Barnes
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Swarup Mitra
- Department of Biomedical Sciences, Marshall University, Huntington, WV 25755, USA
| | - Josée Guindon
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Daniel J Morgan
- Department of Biomedical Sciences, Marshall University, Huntington, WV 25755, USA.
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Martinez-Torres S, Mesquida-Veny F, Del Rio JA, Hervera A. Injury-induced activation of the endocannabinoid system promotes axon regeneration. iScience 2023; 26:106814. [PMID: 37235048 PMCID: PMC10205787 DOI: 10.1016/j.isci.2023.106814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/31/2023] [Accepted: 05/01/2023] [Indexed: 05/28/2023] Open
Abstract
Regeneration after a peripheral nerve injury still remains a challenge, due to the limited regenerative potential of axons after injury. While the endocannabinoid system (ECS) has been widely studied for its neuroprotective and analgesic effects, its role in axonal regeneration and during the conditioning lesion remains unexplored. In this study, we observed that a peripheral nerve injury induces axonal regeneration through an increase in the endocannabinoid tone. We also enhanced the regenerative capacity of dorsal root ganglia (DRG) neurons through the inhibition of endocannabinoid degradative enzyme MAGL or a CB1R agonist. Our results suggest that the ECS, via CB1R and PI3K-pAkt pathway activation, plays an important role in promoting the intrinsic regenerative capacity of sensory neurons after injury.
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Affiliation(s)
- Sara Martinez-Torres
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain
- Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain
- Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Francina Mesquida-Veny
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain
- Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain
- Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - José Antonio Del Rio
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain
- Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain
- Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Arnau Hervera
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain
- Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain
- Institute of Neuroscience, University of Barcelona, Barcelona, Spain
- Clinical Neuroimmunology Group, Vall Hebron Research Institute (VHIR), Barcelona, Spain
- Multiple Sclerosis Centre of Catalonia (CEM-CAT), Barcelona, Spain
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Police A, Kumar Shankar V, Pandey P, Rangappa S, Doerksen RJ, Narasimha Murthy S. Novel Topical Anandamide Formulation for Alleviating Peripheral Neuropathic Pain. Int J Pharm 2023:123085. [PMID: 37245739 DOI: 10.1016/j.ijpharm.2023.123085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/01/2023] [Accepted: 05/23/2023] [Indexed: 05/30/2023]
Abstract
Peripheral neuropathy (PN) is a condition of peripheral nerve damage leading to severe pain. The first line therapies are associated with adverse psychotropic effects (PSE) and second line therapies are not efficient enough to relieve pain. There is an unmet drug need for relieving pain effectively without PSE in PN. Anandamide, an endocannabinoid activates cannabinoid receptors to relieve the pain due to peripheral neuropathy (PN). Anandamide has a very short biological half-life as they are extensively metabolized by fatty acid amide hydrolase enzyme (FAAH). Regional delivery of safe FAAH inhibitor (FI) with anandamide would be beneficial for PN without psychotropic effects. The objective of the study is to identify a safe FAAH inhibitor and deliver the anandamide in combination with the FAAH inhibitor topically for the management of PN. The FAAH inhibition potential of silymarin constituents was evaluated by molecular docking and in vitro studies. The topical gel formulation was developed to deliver anandamide and FI. The formulation was assessed in chemotherapeutic agent-induced peripheral neuropathy rat models to relieve mechanical-allodynia and thermal-hyperalgesia. The molecular docking studies demonstrated that the Prime MM-GBSA free energy of silymarin constituents were in the order of silybin > isosilybin > silychristin > taxifolin > silydianin. In in vitro studies, silybin 20 µM inhibited >61.8% of FAAH activity and increased the half-life of anandamide. The developed formulation increased permeation of anandamide and silybin across the porcine skin. Furthermore, on the application of anandamide and anandamide-silybin gel to rat paws, there was a significant increase in the pain threshold for allodynic and hyperalgesic stimulus up to 1 h and 4 h, respectively. The topical anandamide with silybin delivery approach could serve to alleviate peripheral neuropathy efficiently and thus could minimize unwanted CNS side effects of synthetic or natural cannabinoids in patients.
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Affiliation(s)
- Anitha Police
- Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
| | - Vijay Kumar Shankar
- Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
| | - Pankaj Pandey
- National Center for Natural Products Research, University of Mississippi, University, MS 38677, USA.
| | | | - Robert J Doerksen
- Department of BioMolecular Sciences, Division of Medicinal Chemistry, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
| | - S Narasimha Murthy
- Topical Products Testing LLC, Oxford, MS 38655, USA; Institute for Drug Delivery and Biomedical Research, Bangalore, India.
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Zhang SB, Zhao GH, Lv TR, Gong CY, Shi YQ, Nan W, Zhang HH. Bibliometric and visual analysis of microglia-related neuropathic pain from 2000 to 2021. Front Mol Neurosci 2023; 16:1142852. [PMID: 37273906 PMCID: PMC10233022 DOI: 10.3389/fnmol.2023.1142852] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/28/2023] [Indexed: 06/06/2023] Open
Abstract
Background Microglia has gradually gained researchers' attention in the past few decades and has shown its promising prospect in treating neuropathic pain. Our study was performed to comprehensively evaluate microglia-related neuropathic pain via a bibliometric approach. Methods We retrospectively reviewed publications focusing on microglia-related neuropathic pain from 2000 to 2021 in WoSCC. VOS viewer software and CiteSpace software were used for statistical analyses. Results A total of 2,609 articles were finally included. A steady increase in the number of relevant publications was observed in the past two decades. China is the most productive country, while the United States shares the most-cited and highest H-index country. The University of London, Kyushu University, and the University of California are the top 3 institutions with the highest number of publications. Molecular pain and Pain are the most productive and co-cited journals, respectively. Inoue K (Kyushu University) is the most-contributed researcher and Ji RR (Duke University) ranks 1st in both average citations per article and H-index. Keywords analyses revealed that pro-inflammatory cytokines shared the highest burst strength. Sex differences, neuroinflammation, and oxidative stress are the emerging keywords in recent years. Conclusion In the field of microglia-related neuropathic pain, China is the largest producer and the United States is the most influential country. The signaling communication between microglia and neurons has continued to be vital in this field. Sexual dimorphism, neuroinflammation, and stem-cell therapies might be emerging trends that should be closely monitored.
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Affiliation(s)
- Shun-Bai Zhang
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
| | - Guang-Hai Zhao
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
| | - Tian-Run Lv
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
| | - Chao-Yang Gong
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
| | - Yong-Qiang Shi
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
| | - Wei Nan
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
| | - Hai-Hong Zhang
- Lanzhou University Second Hospital, Lanzhou, China
- Orthopaedics Key Laboratory of Gansu Province, Lanzhou, China
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Wen J, Sackett S, Tanaka M, Zhang Y. Therapeutic Effects of Combined Treatment with the AEA Hydrolysis Inhibitor PF04457845 and the Substrate Selective COX-2 Inhibitor LM4131 in the Mouse Model of Neuropathic Pain. Cells 2023; 12:cells12091275. [PMID: 37174675 PMCID: PMC10177584 DOI: 10.3390/cells12091275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/24/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
Chronic neuropathic pain resulting from peripheral nerve damage is a significant clinical problem, which makes it imperative to develop the mechanism-based therapeutic approaches. Enhancement of endogenous cannabinoids by blocking their hydrolysis has been shown to reduce inflammation and neuronal damage in a number of neurological disorders and neurodegenerative diseases. However, recent studies suggest that inhibition of their hydrolysis can shift endocannabinoids 2-arachidonoyl glycerol (2-AG) and anandamide (AEA) toward the oxygenation pathway mediated by cyclooxygenase-2 (COX-2) to produce proinflammatory prostaglandin glycerol esters (PG-Gs) and prostaglandin ethanolamides (PG-EAs). Thus, blocking both endocannabinoid hydrolysis and oxygenation is likely to be more clinically beneficial. In this study, we used the chronic constriction injury (CCI) mouse model to explore the therapeutic effects of simultaneous inhibition of AEA hydrolysis and oxygenation in the treatment of neuropathic pain. We found that the fatty acid amide hydrolase (FAAH) inhibitor PF04457845 and the substrate-selective COX-2 inhibitor LM4131 dose-dependently reduced thermal hyperalgesia and mechanical allodynia in the CCI mice. In addition to ameliorating the pain behaviors, combined treatment with subeffective doses of these inhibitors greatly attenuated the accumulation of inflammatory cells in both sciatic nerve and spinal cord. Consistently, the increased proinflammatory cytokines IL-1β, IL-6, and chemokine MCP-1 in the CCI mouse spinal cord and sciatic nerve were also significantly reduced by combination of low doses of PF04457845 and LM4131 treatment. Therefore, our study suggests that simultaneous blockage of endocannabinoid hydrolysis and oxygenation by using the substrate-selective COX-2 inhibitor, which avoids the cardiovascular and gastrointestinal side effects associated with the use of general COX-2 inhibitors, might be a suitable strategy for the treatment of inflammatory and neuropathic pain.
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Affiliation(s)
- Jie Wen
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Scott Sackett
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Mikiei Tanaka
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Yumin Zhang
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
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Zeng X, Mai J, Xie H, Yang L, Liu X. Activation of CB1R alleviates central sensitization by regulating HCN2-pNR2B signaling in a chronic migraine rat model. J Headache Pain 2023; 24:44. [PMID: 37085778 PMCID: PMC10120244 DOI: 10.1186/s10194-023-01580-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/17/2023] [Indexed: 04/23/2023] Open
Abstract
BACKGROUND Central sensitization has been widely accepted as an underlying pathophysiological mechanism of chronic migraine (CM), activation of cannabinoid type-1 receptor (CB1R) exerts antinociceptive effects by relieving central sensitization in many pain models. However, the role of CB1R in the central sensitization of CM is still unclear. METHODS A CM model was established by infusing inflammatory soup (IS) into the dura of male Wistar rats for 7 days, and hyperalgesia was assessed by the mechanical and thermal thresholds. In the periaqueductal gray (PAG), the mRNA and protein levels of CB1R and hyperpolarization-activated cyclic nucleotide-gated cation channel 2 (HCN2) were measured by qRT-PCR and western blotting. After intraventricular injection of Noladin ether (NE) (a CB1R agonist), ZD 7288 (an HCN2 blocker), and AM 251 (a CB1R antagonist), the expression of tyrosine phosphorylation of N-methyl-D-aspartate receptor subtype 2B (pNR2B), calcium-calmodulin-dependent kinase II (CaMKII), and phosphorylated cAMP-responsive element binding protein (pCREB) was detected, and central sensitization was evaluated by the expression of calcitonin gene-related peptide (CGRP), c-Fos, and substance P (SP). Synaptic-associated protein (postsynaptic density protein 95 (PSD95) and synaptophysin (Syp)) and synaptic ultrastructure were detected to explore synaptic plasticity in central sensitization. RESULTS We observed that the mRNA and protein levels of CB1R and HCN2 were both significantly increased in the PAG of CM rats. The application of NE or ZD 7288 ameliorated IS-induced hyperalgesia; repressed the pNR2B/CaMKII/pCREB pathway; reduced CGRP, c-Fos, SP, PSD95, and Syp expression; and inhibited synaptic transmission. Strikingly, the application of ZD 7288 relieved AM 251-evoked elevation of pNR2B, CGRP, and c-Fos expression. CONCLUSIONS These data reveal that activation of CB1R alleviates central sensitization by regulating HCN2-pNR2B signaling in CM rats. The activation of CB1R might have a positive influence on the prevention of CM by mitigating central sensitization.
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Affiliation(s)
- Xiaoxu Zeng
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, China
| | - Jia Mai
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, China
| | - Hongjian Xie
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, China
| | - Ling Yang
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, China
| | - Xiaojuan Liu
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, China.
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, China.
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10
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Nouh RA, Kamal A, Abdelnaser A. Cannabinoids and Multiple Sclerosis: A Critical Analysis of Therapeutic Potentials and Safety Concerns. Pharmaceutics 2023; 15:pharmaceutics15041151. [PMID: 37111637 PMCID: PMC10146800 DOI: 10.3390/pharmaceutics15041151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 04/09/2023] Open
Abstract
Multiple sclerosis (MS) is a complicated condition in which the immune system attacks myelinated axons in the central nervous system (CNS), destroying both myelin and axons to varying degrees. Several environmental, genetic, and epigenetic factors influence the risk of developing the disease and how well it responds to treatment. Cannabinoids have recently sparked renewed interest in their therapeutic applications, with growing evidence for their role in symptom control in MS. Cannabinoids exert their roles through the endogenous cannabinoid (ECB) system, with some reports shedding light on the molecular biology of this system and lending credence to some anecdotal medical claims. The double nature of cannabinoids, which cause both positive and negative effects, comes from their actions on the same receptor. Several mechanisms have been adopted to evade this effect. However, there are still numerous limitations to using cannabinoids to treat MS patients. In this review, we will explore and discuss the molecular effect of cannabinoids on the ECB system, the various factors that affect the response to cannabinoids in the body, including the role of gene polymorphism and its relation to dosage, assessing the positive over the adverse effects of cannabinoids in MS, and finally, exploring the possible functional mechanism of cannabinoids in MS and the current and future progress of cannabinoid therapeutics.
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Affiliation(s)
- Roua A. Nouh
- Department of Chemistry, School of Sciences and Engineering, The American University in Cairo, New Cairo 11835, Egypt
| | - Ahmed Kamal
- Biochemistry Department, Faculty of Science, Suez University, P.O. Box 43518, Suez 43533, Egypt
| | - Anwar Abdelnaser
- Institute of Global Health and Human Ecology, School of Sciences and Engineering, The American University in Cairo, P.O. Box 74, New Cairo 11835, Egypt
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11
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Microglial Cannabinoid CB 2 Receptors in Pain Modulation. Int J Mol Sci 2023; 24:ijms24032348. [PMID: 36768668 PMCID: PMC9917135 DOI: 10.3390/ijms24032348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/17/2023] [Accepted: 01/19/2023] [Indexed: 01/27/2023] Open
Abstract
Pain, especially chronic pain, can strongly affect patients' quality of life. Cannabinoids ponhave been reported to produce potent analgesic effects in different preclinical pain models, where they primarily function as agonists of Gi/o protein-coupled cannabinoid CB1 and CB2 receptors. The CB1 receptors are abundantly expressed in both the peripheral and central nervous systems. The central activation of CB1 receptors is strongly associated with psychotropic adverse effects, thus largely limiting its therapeutic potential. However, the CB2 receptors are promising targets for pain treatment without psychotropic adverse effects, as they are primarily expressed in immune cells. Additionally, as the resident immune cells in the central nervous system, microglia are increasingly recognized as critical players in chronic pain. Accumulating evidence has demonstrated that the expression of CB2 receptors is significantly increased in activated microglia in the spinal cord, which exerts protective consequences within the surrounding neural circuitry by regulating the activity and function of microglia. In this review, we focused on recent advances in understanding the role of microglial CB2 receptors in spinal nociceptive circuitry, highlighting the mechanism of CB2 receptors in modulating microglia function and its implications for CB2 receptor- selective agonist-mediated analgesia.
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12
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Expression and Kinetics of Endogenous Cannabinoids in the Brain and Spinal Cord of a Spare Nerve Injury (SNI) Model of Neuropathic Pain. Cells 2022; 11:cells11244130. [PMID: 36552893 PMCID: PMC9776457 DOI: 10.3390/cells11244130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/14/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
The role of endogenous cannabinoids in neuropathic pain has been actively studied, among which 2-arachidonoyl glycerol (2-AG) has received the most attention. However, owing to its chemical properties, direct detection of 2-AG distribution in tissues is difficult. Moreover, although desorption electrospray ionization mass spectrometry imaging (DESI-MSI) has enabled the detection of 2-AG, its distribution in the brain and spinal cord of neuropathic pain models has not been reported. In this study, the expression and distribution of 2-AG in the brain and spinal cord of a spare nerve injury (SNI) mice model of neuropathic pain was examined using DESI-MSI. The brain and lumbar spinal cord were collected and analyzed on days 3, 7, and 21 after treatment. On days 3 and 7 after treatment, 2-AG expression in the SNI model was decreased in the hypothalamus, midbrain, and especially in the periaqueductal gray (PAG) region but increased in the lumbar spinal cord. On day 21, the SNI model showed decreased 2-AG expression in the hypothalamus, but the difference from the control was not significant. Furthermore, there were no differences in 2-AG expression between the lumbar spinal cord, midbrain, or PAG. These data suggest that 2-AG might be involved in pain control.
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13
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Anand U, Pacchetti B, Anand P, Sodergren MH. The Endocannabinoid Analgesic Entourage Effect: Investigations in Cultured DRG Neurons. J Pain Res 2022; 15:3493-3507. [PMID: 36394060 PMCID: PMC9642605 DOI: 10.2147/jpr.s378876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 10/08/2022] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND The endocannabinoid 2-Arachidonyl glycerol (2-AG) exerts dose-related anti-nociceptive effects, which are potentiated by the related but inactive 2-palmitoyl glycerol (2-PG) and 2-linoleoyl glycerol (2-LG). This potentiation of analgesia and other in vivo measures was described as the "entourage effect". We investigated this effect on TRPV1 signalling in cultured dorsal root ganglion (DRG) nociceptors. METHODS Adult rat DRG neurons were cultured in medium containing NGF and GDNF at 37°C. 48 h later cultures were loaded with 2 µM Fura2AM for calcium imaging, and treated with 2-AG, 2-PG and 2-LG, individually or combined, for 5 min, followed by 1 µMol capsaicin. The amplitude and latency of capsaicin responses were measured (N=3-7 rats, controls N=16), and analysed. RESULTS In controls, 1 µMol capsaicin elicited immediate calcium influx in a subset of neurons, with average latency of 1.27 ± 0.2 s and amplitude of 0.15 ± 0.01 Units. 2-AG (10-100 µMol) elicited calcium influx in some neurons. In the presence of 2-AG (0.001-100 µMol), capsaicin responses were markedly delayed in 64% neurons by up to 320 s (P<0.001). 2-PG increased capsaicin response latency at 0.1 nMol-100 µMol (P<0.001), in 60% neurons, as did 2-LG at 0.1-100 µMol (P<0.001), in 76% neurons. Increased capsaicin response latency due to 2-AG and 2-PG was sensitive to the CB2 but not to the CB1 receptor antagonist. Combined application of 1 µMol 2-AG, 5 µMol 2-PG and 10 µMol 2-LG, also resulted in significantly increased capsaicin response latency up to 281.5 ± 41.5 s (P<0.001), in 96% neurons, that was partially restored by the CB2, but not the CB1 antagonist. CONCLUSION 2-AG, 2-LG and 2-PG significantly delayed TRPV1 signalling in the majority of capsaicin-sensitive DRG neurons, that was markedly increased following combined application. Further studies of these endocannabinoids are required to identify the underlying mechanisms.
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Affiliation(s)
- Uma Anand
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, W12 0HS, UK
| | | | - Praveen Anand
- Professor of Clinical Neurology, Department of Brain Sciences, Imperial College London, London, W12 0HS, UK
| | - Mikael Hans Sodergren
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, W12 0HS, UK
- Curaleaf International Limited, London, EC2A 2EW, UK
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14
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Yang L, Lu J, Guo J, Chen J, Xiong F, Wang X, Chen L, Yu C. Ventrolateral Periaqueductal Gray Astrocytes Regulate Nociceptive Sensation and Emotional Motivation in Diabetic Neuropathic Pain. J Neurosci 2022; 42:8184-8199. [PMID: 36109166 PMCID: PMC9636999 DOI: 10.1523/jneurosci.0920-22.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 09/06/2022] [Accepted: 09/11/2022] [Indexed: 11/21/2022] Open
Abstract
Diabetic neuropathic pain (DNP) is a diabetes complication experienced by many patients. Ventrolateral periaqueductal gray (vlPAG) neurons are essential mediators of the descending pain modulation system, yet the role of vlPAG astrocytes in DNP remains unclear. The present study applied a multidimensional approach to elucidate the role of these astrocytes in DNP. We verified the activation of astrocytes in different regions of the PAG in male DNP-model rats. We found that only astrocytes in the vlPAG exhibited increased growth. Furthermore, we described differences in vlPAG astrocyte activity at different time points during DNP progression. After the 14th day of modeling, vlPAG astrocytes exhibited obvious activation and morphologic changes. Furthermore, activation of Gq-designer receptors exclusively activated by a designer drug (Gq-DREADDs) in vlPAG astrocytes in naive male rats induced neuropathic pain-like symptoms and pain-related aversion, whereas activation of Gi-DREADDs in vlPAG astrocytes in male DNP-model rats alleviated sensations of pain and promoted pain-related preference behavior. Thus, bidirectional manipulation of vlPAG astrocytes revealed their potential to regulate pain. Surprisingly, activation of Gi-DREADDs in vlPAG astrocytes also mitigated anxiety-like behavior induced by DNP. Thus, our results provide direct support for the hypothesis that vlPAG astrocytes regulate diabetes-associated neuropathic pain and concomitant anxiety-like behavior.SIGNIFICANCE STATEMENT Many studies examined the association between the ventrolateral periaqueductal gray (vlPAG) and neuropathic pain. However, few studies have focused on the role of vlPAG astrocytes in diabetic neuropathic pain (DNP) and DNP-related emotional changes. This work confirmed the role of vlPAG astrocytes in DNP by applying a more direct and robust approach. We used chemogenetics to bidirectionally manipulate the activity of vlPAG astrocytes and revealed that vlPAG astrocytes regulate DNP and pain-related behavior. In addition, we discovered that activation of Gi-designer receptors exclusively activated by a designer drug in vlPAG astrocytes alleviated anxiety-like behavior induced by DNP. Together, these findings provide new insights into DNP and concomitant anxiety-like behavior and supply new therapeutic targets for treating DNP.
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Affiliation(s)
- Lan Yang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Jingshan Lu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
- Fujian Center for Safety Evaluation of New Drug, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Jianpeng Guo
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Jian Chen
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Fangfang Xiong
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Xinyao Wang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Li Chen
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
- Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, Fujian Medical University, Fuzhou, 350122, Fujian China
| | - Changxi Yu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, Fujian China
- Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, Fujian Medical University, Fuzhou, 350122, Fujian China
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15
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Teuchmann HL, Hogri R, Heinke B, Sandkühler J. Anti-Nociceptive and Anti-Aversive Drugs Differentially Modulate Distinct Inputs to the Rat Lateral Parabrachial Nucleus. THE JOURNAL OF PAIN 2022; 23:1410-1426. [PMID: 35339662 DOI: 10.1016/j.jpain.2022.03.234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 02/16/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
The lateral parabrachial nucleus (LPBN) plays an important role in the processing and establishment of pain aversion. It receives direct input from the superficial dorsal horn and forms reciprocal connections with the periaqueductal grey matter (PAG), which is critical for adaptive behaviour and the modulation of pain processing. Here, using in situ hybridization and optogenetics combined with in vitro electrophysiology, we characterized the spinal- and PAG-LPBN circuits of rats. We found spinoparabrachial projections to be strictly glutamatergic, while PAG neurons send glutamatergic and GABAergic projections to the LPBN. We next investigated the effects of drugs with anti-aversive and/or anti-nociceptive properties on these synapses: The µ-opioid receptor agonist DAMGO (10 µM) reduced spinal and PAG synaptic inputs onto LPBN neurons, and the excitability of LPBN neurons receiving these inputs. The benzodiazepine receptor agonist diazepam (5 µM) strongly enhanced GABAergic action at inhibitory PAG-LPBN synapses. The cannabinoid receptor agonist WIN 55,212-2 (5 µM) led to a reduction in inhibitory and excitatory PAG-LPBN synaptic transmission, without affecting excitatory spinoparabrachial synaptic transmission. Our study reveals that opioid, cannabinoid and benzodiazepine receptor agonists differentially affect distinct LPBN synapses. These findings may support the efforts to develop pinpointed therapies for pain patients. PERSPECTIVE: The LPBN is an important brain region for the control of pain aversion versus recuperation, and as such constitutes a promising target for developing new strategies for pain management. We show that clinically-relevant drugs have complex and pathway-specific effects on LPBN processing of putative nociceptive and aversive inputs.
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Affiliation(s)
- Hannah Luise Teuchmann
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Roni Hogri
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Bernhard Heinke
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jürgen Sandkühler
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria.
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16
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Jiang Z, Wang Q, Zhao J, Wang J, Li Y, Dai W, Zhang X, Fang Z, Hou W, Xiong L. Sex-specific cannabinoid 1 receptors on GABAergic neurons in the ventrolateral periaqueductal gray mediate analgesia in mice. J Comp Neurol 2022; 530:2315-2334. [PMID: 35716006 DOI: 10.1002/cne.25334] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 04/04/2022] [Accepted: 04/13/2022] [Indexed: 11/07/2022]
Abstract
Sex differences in analgesic effects have gradually attracted public attention in preclinical and clinical studies. Both human and animal females are more sensitive to cannabinoid antinociception than males. Expression of the cannabinoid 1 receptor (CB1 R) and the function of the endocannabinoid system have been explored in both male and female mice and CB1 Rs in the ventrolateral periaqueductal gray (vlPAG) participate in antinociception. However, whether there are cell-type- and sex-specific patterns of vlPAG CB1 R expression that affect analgesia is unknown. In the current study, we either activated or inhibited CB1 Rs in the vlPAG and found that female mice produced stronger analgesia or developed more robust mechanical allodynia than males did. Specific deletion of GABAergic CB1 Rs in the vlPAG promoted stronger mechanical allodynia in female mice than that in male mice. However, no sex differences in cannabinoid antinociception were found following chemogenetic inhibition of GABAergic neurons. Using fluorescence in situ hybridization, we found that the sex difference in cannabinoid antinociception was due to females having higher expression of GABAergic CB1 Rs in the vlPAG than males. Furthermore, activation of CB1 Rs in the vlPAG significantly reduced the frequency of GABA-mediated spontaneous inhibitory postsynaptic currents recorded in vGlut2-tdTomato positive neurons in both sexes. This effect was greater in females than males and this reduction was closely related to CB1 R expression difference between sexes. Our work indicates that vlPAG GABAergic CB1 Rs modulate cannabinoid-mediated analgesia in a sex-specific manner, which may provide a potential explanation of sex difference found in the analgesic effect of cannabinoids.
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Affiliation(s)
- Zhenhua Jiang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Qun Wang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Jianshuai Zhao
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Jiajia Wang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - You Li
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Wei Dai
- Hangzhou Sanatorium Health Management Center, Hangzhou, People's Republic of China
| | - Xiao Zhang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Zongping Fang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Wugang Hou
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
| | - Lize Xiong
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xian, Shaanxi Province, China
- Department of Anesthesiology and Perioperative Medicine, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
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17
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Zhang Y, Ke J, Zhou Y, Liu X, Huang T, Wang F. Sex-specific characteristics of cells expressing the cannabinoid 1 receptor in the dorsal horn of the lumbar spinal cord. J Comp Neurol 2022; 530:2451-2473. [PMID: 35580011 DOI: 10.1002/cne.25342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 04/28/2022] [Accepted: 05/02/2022] [Indexed: 12/20/2022]
Abstract
It is becoming increasingly clear that robust sex differences exist in the processing of acute and chronic pain in both rodents and humans. However, the underlying mechanism has not been well characterized. The dorsal horn of the lumbar spinal cord is the fundamental building block of ascending and descending pain pathways. It has been shown that numerous neurotransmitter and neuromodulator systems in the spinal cord, including the endocannabinoid system and its main receptor, the cannabinoid 1 receptor (CB1 R), play vital roles in processing nociceptive information. Our previous findings have shown that CB1 R mRNA is widely expressed in the brain in sex-dependent patterns. However, the sex-, lamina-, and cell-type-specific characteristics of CB1 R expression in the spinal cord have not been fully described. In this study, the CB1 R-iCre-EGFP mouse strain was generated to label and identify CB1 R-positive (CB1 RGFP ) cells. We reported no sex difference in CB1 R expression in the lumbar dorsal horn of the spinal cord, but a dynamic distribution within superficial laminae II and III in female mice between estrus and nonestrus phases. Furthermore, the cell-type-specific CB1 R expression pattern in the dorsal horn was similar in both sexes. Over 50% of CB1 RGFP cells were GABAergic neurons, and approximately 25% were glycinergic and 20-30% were glutamatergic neurons. The CB1 R-expressing cells also represented a subset of spinal projection neurons. Overall, our work indicates a highly consistent distribution pattern of CB1 RGFP cells in the dorsal horn of lumbar spinal cord in males and females.
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Affiliation(s)
- Yulin Zhang
- Shenzhen Key Lab of Translational Research for Brain Diseases, Shenzhen Key Lab of Drug Addiction, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jin Ke
- Shenzhen Key Lab of Translational Research for Brain Diseases, Shenzhen Key Lab of Drug Addiction, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yuan Zhou
- Shenzhen Key Lab of Translational Research for Brain Diseases, Shenzhen Key Lab of Drug Addiction, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xue Liu
- Shenzhen Key Lab of Translational Research for Brain Diseases, Shenzhen Key Lab of Drug Addiction, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Tianwen Huang
- Shenzhen Key Lab of Translational Research for Brain Diseases, Shenzhen Key Lab of Drug Addiction, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Feng Wang
- Shenzhen Key Lab of Translational Research for Brain Diseases, Shenzhen Key Lab of Drug Addiction, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
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18
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Chang S, Li X, Zheng Y, Shi H, Zhang D, Jing B, Chen Z, Qian G, Zhao G. Kaempferol exerts a neuroprotective effect to reduce neuropathic pain through TLR4/NF-ĸB signaling pathway. Phytother Res 2022; 36:1678-1691. [PMID: 35234314 PMCID: PMC9311149 DOI: 10.1002/ptr.7396] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 01/03/2022] [Accepted: 01/04/2022] [Indexed: 11/11/2022]
Abstract
Switching microglial polarization from the M1 to M2 phenotype is a promising therapeutic strategy for neuropathic pain (NP). Toll‐like receptor 4 (TLR4) is activated by lipopolysaccharide (LPS). Uncontrolled activation of TLR4 has been proven to trigger chronic inflammation. Kaempferol, a dietary flavonoid, is known to have anti‐inflammatory properties. This study is aimed to investigate the analgesic and anti‐inflammatory effects and the underlying mechanisms of kaempferol, which were explored with an NP model in vivo and LPS‐induced injury in microglial BV2 cells in vitro. The levels of proinflammatory cytokines were evaluated. H&E staining and immunohistochemistry were used to assess the sciatic nerve condition after chronic constriction injury surgery. Western blotting and immunofluorescence were used to determine whether TLR4/NF‐ĸB signaling pathway plays a major role in kaempferol‐mediated alleviation of neuroinflammation. Quantitative real‐time polymerase chain reaction and flow cytometry were used to examine the modulator effect of kaempferol on microglial M1/M2 polarization. We found that kaempferol treatment can significantly reduce NP and proinflammatory cytokine production. Kaempferol attenuated the activation of TLR4/NF‐κB pathways in LPS‐activated BV2 cells. The analgesic effects of kaempferol on NP may be due to inhibition of microglia activation and switching the M1 to M2 phenotype.
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Affiliation(s)
- Shiquan Chang
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Xin Li
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Yachun Zheng
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Huimei Shi
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Di Zhang
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Bei Jing
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Zhenni Chen
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Guoqiang Qian
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Guoping Zhao
- College of Traditional Chinese Medicine, Jinan University, Guangzhou, China
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19
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Que W, Wu Z, Chen M, Zhang B, You C, Lin H, Zhao Z, Liu M, Qiu H, Cheng Y. Molecular Mechanism of Gelsemium elegans (Gardner and Champ.) Benth. Against Neuropathic Pain Based on Network Pharmacology and Experimental Evidence. Front Pharmacol 2022; 12:792932. [PMID: 35046814 PMCID: PMC8762237 DOI: 10.3389/fphar.2021.792932] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
Gelsemium elegans (Gardner and Champ.) Benth. (Gelsemiaceae) (GEB) is a toxic plant indigenous to Southeast Asia especially China, and has long been used as Chinese folk medicine for the treatment of various types of pain, including neuropathic pain (NPP). Nevertheless, limited data are available on the understanding of the interactions between ingredients-targets-pathways. The present study integrated network pharmacology and experimental evidence to decipher molecular mechanisms of GEB against NPP. The candidate ingredients of GEB were collected from the published literature and online databases. Potentially active targets of GEB were predicted using the SwissTargetPrediction database. NPP-associated targets were retrieved from GeneCards, Therapeutic Target database, and DrugBank. Then the protein-protein interaction network was constructed. The DAVID database was applied to Gene Ontology and Kyoto Encyclopedia of Genes and Genome pathway enrichment analysis. Molecular docking was employed to validate the interaction between ingredients and targets. Subsequently, a 50 ns molecular dynamics simulation was performed to analyze the conformational stability of the protein-ligand complex. Furthermore, the potential anti-NPP mechanisms of GEB were evaluated in the rat chronic constriction injury model. A total of 47 alkaloids and 52 core targets were successfully identified for GEB in the treatment of NPP. Functional enrichment analysis showed that GEB was mainly involved in phosphorylation reactions and nitric oxide synthesis processes. It also participated in 73 pathways in the pathogenesis of NPP, including the neuroactive ligand-receptor interaction signaling pathway, calcium signaling pathway, and MAPK signaling pathway. Interestingly, 11-Hydroxyrankinidin well matched the active pockets of crucial targets, such as EGFR, JAK1, and AKT1. The 11-hydroxyrankinidin-EGFR complex was stable throughout the entire molecular dynamics simulation. Besides, the expression of EGFR and JAK1 could be regulated by koumine to achieve the anti-NPP action. These findings revealed the complex network relationship of GEB in the "multi-ingredient, multi-target, multi-pathway" mode, and explained the synergistic regulatory effect of each complex ingredient of GEB based on the holistic view of traditional Chinese medicine. The present study would provide a scientific approach and strategy for further studies of GEB in the treatment of NPP in the future.
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Affiliation(s)
- Wancai Que
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China.,College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Zhaoyang Wu
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China.,College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Maohua Chen
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China
| | - Binqing Zhang
- College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Chuihuai You
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Hailing Lin
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China
| | - Zhichang Zhao
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China.,College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Maobai Liu
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China.,College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Hongqiang Qiu
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China.,College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Yu Cheng
- Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, China.,College of Pharmacy, Fujian Medical University, Fuzhou, China.,Department of Pharmacy, Shengjing Hospital of China Medical University, Shenyang, China
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20
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Ford NC, Barpujari A, He SQ, Huang Q, Zhang C, Dong X, Guan Y, Raja SN. Role of primary sensory neurone cannabinoid type-1 receptors in pain and the analgesic effects of the peripherally acting agonist CB-13 in mice. Br J Anaesth 2022; 128:159-173. [PMID: 34844727 PMCID: PMC8787781 DOI: 10.1016/j.bja.2021.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/27/2021] [Accepted: 10/14/2021] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Cannabinoid type-1 receptors (CB1Rs) are expressed in primary sensory neurones, but their role in pain modulation remains unclear. METHODS We produced Pirt-CB1R conditional knockout (cKO) mice to delete CB1Rs in primary sensory neurones selectively, and used behavioural, pharmacological, and electrophysiological approaches to examine the influence of peripheral CB1R signalling on nociceptive and inflammatory pain. RESULTS Conditional knockout of Pirt-CB1R did not alter mechanical or heat nociceptive thresholds, complete Freund adjuvant-induced inflammation, or heat hyperalgesia in vivo. The intrinsic membrane properties of small-diameter dorsal root ganglion neurones were also comparable between cKO and wild-type mice. Systemic administration of CB-13, a peripherally restricted CB1/CB2R dual agonist (5 mg kg-1), inhibited nociceptive pain and complete Freund adjuvant-induced inflammatory pain. These effects of CB-13 were diminished in Pirt-CB1R cKO mice. In small-diameter neurones from wild-type mice, CB-13 concentration-dependently inhibited high-voltage activated calcium current (HVA-ICa) and induced a rightward shift of the channel open probability curve. The effects of CB-13 were significantly attenuated by AM6545 (a CB1R antagonist) and Pirt-CB1R cKO. CONCLUSION CB1R signalling in primary sensory neurones did not inhibit nociceptive or inflammatory pain, or the intrinsic excitability of nociceptive neurones. However, peripheral CB1Rs are important for the analgesic effects of systemically administered CB-13. In addition, HVA-ICa inhibition appears to be a key ionic mechanism for CB-13-induced pain inhibition. Thus, peripherally restricted CB1R agonists could have utility for pain treatment.
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Affiliation(s)
- Neil C Ford
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Awinita Barpujari
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shao-Qiu He
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Qian Huang
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chi Zhang
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xinzhong Dong
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurological Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yun Guan
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurological Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Srinivasa N Raja
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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21
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Ao Z, Cai H, Wu Z, Krzesniak J, Tian C, Lai YY, Mackie K, Guo F. Human Spinal Organoid-on-a-Chip to Model Nociceptive Circuitry for Pain Therapeutics Discovery. Anal Chem 2021; 94:1365-1372. [PMID: 34928595 DOI: 10.1021/acs.analchem.1c04641] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The discovery of new pain therapeutics targeting human nociceptive circuitry is an emerging, exciting, and rewarding field. However, current models for evaluating prospective new therapeutics [e.g., animals and two-dimensional (2D) in vitro cultures] fail to fully recapitulate the complexity of human nociceptive neuron and dorsal horn neuron biology, significantly limiting the development of novel pain therapeutics. Here, we report human spinal organoid-on-a-chip devices for modeling the biology and electrophysiology of human nociceptive neurons and dorsal horn interneurons in nociceptive circuitry. Our device can be simply made through the integration of a membrane with a three-dimensional (3D)-printed organoid holder. By combining air-liquid interface culture and spinal organoid protocols, our devices can differentiate human stem cells into human sensori-spinal-cord organoids with dorsal spinal cord interneurons and sensory neurons. By easily transferring from culture well plates to the multiple-electrode array (MEA) system, our device also allows the plug-and-play measurement of organoid activity for testing nociceptive modulators (e.g., mustard oil, capsaicin, velvet ant venom, etc.). Our organoid-on-a-chip devices are cost-efficient, scalable, easy to use, and compatible with conventional well plates, allowing the plug-and-play measurement of spinal organoid electrophysiology. By the integration of human sensory-spinal-cord organoids with our organoid-on-a-chip devices, our method may hold the promising potential to screen and validate novel therapeutics for human pain medicine discovery.
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Affiliation(s)
- Zheng Ao
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana 47405, United States
| | - Hongwei Cai
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana 47405, United States
| | - Zhuhao Wu
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana 47405, United States
| | - Jonathan Krzesniak
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana 47405, United States
| | - Chunhui Tian
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana 47405, United States
| | - Yvonne Y Lai
- Gill Center for Biomolecular Science, and Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405, United States
| | - Ken Mackie
- Gill Center for Biomolecular Science, and Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405, United States
| | - Feng Guo
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana 47405, United States
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22
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Xiong B, You W, Luo Y, Jin G, Wu M, Xu Y, Yang J, Huang H, Yu C. Investigation of the Possible Allostery of Koumine Extracted From Gelsemium elegans Benth. And Analgesic Mechanism Associated With Neurosteroids. Front Pharmacol 2021; 12:739618. [PMID: 34671258 PMCID: PMC8520994 DOI: 10.3389/fphar.2021.739618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 09/21/2021] [Indexed: 11/13/2022] Open
Abstract
Translocator protein 18 kDa (TSPO) is an evolutionarily conserved 5-transmembrane domain protein, and has been considered as an important therapeutic target for the treatment of pain. We have recently reported the in vitro and in vivo pharmacological characterization of koumine as a TSPO positive allosteric modulator (PAM), more precisely ago-PAM. However, the probe dependence in the allostery of koumine is an important question to resolve, and the possible analgesic mechanism of koumine remains to be clarified. Here, we report the in vivo evaluation of the allostery of koumine when orthosteric ligand PK11195 was used and preliminarily explore the possible analgesic mechanism of koumine associated with neurosteroids. We find that koumine is an ago-PAM of the PK11195-mediated analgesic effect at TSPO, and the analgesic mechanism of this TSPO ago-PAM may be associated with neurosteroids as the analgesic effects of koumine in the formalin-induced inflammatory pain model and chronic constriction injury-induced neuropathic pain model can be antagonized by neurosteroid synthesis inhibitor aminoglutethimide. Although our results cannot fully clarify the allosteric modulatory effect of koumine, it further prove the allostery in TSPO and provide a solid foundation for koumine to be used as a new clinical candidate drug to treat pain.
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Affiliation(s)
- Bojun Xiong
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
| | - Wenbing You
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Yufei Luo
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Guilin Jin
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Minxia Wu
- Public Technology Service Center, Fujian Medical University, Fuzhou, China
| | - Ying Xu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Jian Yang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Huihui Huang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Changxi Yu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
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23
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Jin GJ, Peng X, Chen ZG, Wang YL, Liao WJ. Celastrol attenuates chronic constrictive injury-induced neuropathic pain and inhibits the TLR4/NF-κB signaling pathway in the spinal cord. J Nat Med 2021; 76:268-275. [PMID: 34510370 DOI: 10.1007/s11418-021-01564-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 09/01/2021] [Indexed: 11/29/2022]
Abstract
Tripterygium wilfordii Hook F. is a well-known but poisonous traditional Chinese medicine used for treating a wide variety of inflammatory and autoimmune disorders. Celastrol, a quinone methyl triterpenoid compound and a representative component of T. wilfordii Hook F., shows a variety of pharmacological activities, such as anti-inflammatory and antitumor activities. Here, we investigated the antineuropathic pain (NP) effect of celastrol and its potential mechanisms. Rats with chronic constrictive injury (CCI)-induced NP were used to evaluate the analgesic effect of celastrol. Gabapentin was used as a reference compound (positive control). The results showed that gabapentin (100 mg/kg, i.p.) and multiple doses of celastrol (0.5, 1 and 2 mg/kg, i.p.) increased the threshold of mechanical and thermal pain in the rats with NP. Western blot results showed that celastrol significantly inhibited the activation of microglia and astrocytes in the spinal cord of rats with NP. Additionally, the levels of the proinflammatory cytokines tumor necrosis factor α (TNF-α), interleukin 1β and interleukin 6, detected by ELISA in the spinal cord of the rats with NP, were significantly inhibited by celastrol. Furthermore, celastrol treatment dramatically inhibited the expression of the TLR4/NF-κB signaling pathway in the spinal cord. Taken together, our findings suggested that celastrol could attenuate mechanical and thermal pain in CCI-induced NP, and this protection might be attributed to inhibiting the TLR4/NF-κB signaling pathway and exerting anti-inflammatory effects in the spinal cord.
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Affiliation(s)
- Gui-Juan Jin
- Department of Neonatology, The First People's Hospital of Jingmen, Jingmen, Hubei, China
| | - Xuehuizi Peng
- Department of Children's Rehabilitation, Wuhan Mental Health Center, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Zhi-Guo Chen
- Department of Pharmacy, College of Traditional Chinese Medicine, Yichang Hospital of Traditional Chinese Medicine, Three Gorges University, Yichang, China
| | - Yu-Lin Wang
- Department of Neonatology, The First People's Hospital of Jingmen, Jingmen, Hubei, China
| | - Wen-Jun Liao
- Department of Neonatology, The First People's Hospital of Jingmen, Jingmen, Hubei, China.
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24
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Jin GL, Hong LM, Liu HP, Yue RC, Shen ZC, Yang J, Xu Y, Huang HH, Li Y, Xiong BJ, Su YP, Yu CX. Koumine modulates spinal microglial M1 polarization and the inflammatory response through the Notch-RBP-Jκ signaling pathway, ameliorating diabetic neuropathic pain in rats. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2021; 90:153640. [PMID: 34330066 DOI: 10.1016/j.phymed.2021.153640] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 06/05/2021] [Accepted: 06/22/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Diabetic neuropathic pain (DNP), a complication of diabetes, has serious impacts on human health. As the pathogenesis of DNP is very complex, clinical treatments for DNP is limited. Koumine (KM) is an active ingredient extracted from Gelsemium elegans Benth. that exerts an inhibitory effect on neuropathic pain (NP) in several animal models. PURPOSE To clarify the anti-NP effect of KM on rats with DNP and the molecular mechanisms involving the Notch- Jκ recombination signal binding protein (RBP-Jκ) signaling pathway. METHODS Male Sprague-Dawley rats were administered streptozocin (STZ) by intraperitoneal injection to induce DNP. The effect of KM on mechanical hyperalgesia in rats with DNP was evaluated using the Von Frey test. Microglial polarization in the spinal cord was examined using western blotting and quantitative real-time PCR. The Notch-RBP-Jκ signaling pathway was analysed using western blotting. RESULTS KM attenuated DNP during the observation period. In addition, KM alleviated M1 microglial polarization in STZ-induced rats. Subsequent experiments revealed that Notch-RBP-Jκ signaling pathway was activated in the spinal cord of rats with DNP, and the activation of this pathways was decreased by KM. Additionally, KM-mediated analgesia and deactivation of the Notch-RBP-Jκ signaling pathway were inhibited by the Notch signaling agonist jagged 1, indicating that the anti-DNP effect of KM may be regulated by the Notch-RBP-Jκ signaling pathway. CONCLUSIONS KM is a potentially desirable candidate treatment for DNP that may inhibit microglial M1 polarization through the Notch-RBP-Jκ signaling pathway.
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Affiliation(s)
- Gui-Lin Jin
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China.
| | - Li-Mian Hong
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Department of Pharmacy, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, Fujian 362000, P.R. China
| | - Hai-Ping Liu
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Rong-Cai Yue
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Zu-Cheng Shen
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Jian Yang
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Ying Xu
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Hui-Hui Huang
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Yi Li
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Bo-Jun Xiong
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Yan-Ping Su
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Chang-Xi Yu
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China; Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, Fujian, P.R. China.
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25
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Yamamoto T, Mulpuri Y, Izraylev M, Li Q, Simonian M, Kramme C, Schmidt BL, Seltzman HH, Spigelman I. Selective targeting of peripheral cannabinoid receptors prevents behavioral symptoms and sensitization of trigeminal neurons in mouse models of migraine and medication overuse headache. Pain 2021; 162:2246-2262. [PMID: 33534356 PMCID: PMC8277668 DOI: 10.1097/j.pain.0000000000002214] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/19/2021] [Indexed: 01/03/2023]
Abstract
ABSTRACT Migraine affects ∼15% of the world's population greatly diminishing their quality of life. Current preventative treatments are effective in only a subset of migraine patients, and although cannabinoids seem beneficial in alleviating migraine symptoms, central nervous system side effects limit their widespread use. We developed peripherally restricted cannabinoids (PRCBs) that relieve chronic pain symptoms of cancer and neuropathies, without appreciable central nervous system side effects or tolerance development. Here, we determined PRCB effectiveness in alleviating hypersensitivity symptoms in mouse models of migraine and medication overuse headache. Long-term glyceryl trinitrate (GTN, 10 mg/kg) administration led to increased sensitivity to mechanical stimuli and increased expression of phosphorylated protein kinase A, neuronal nitric oxide synthase, and transient receptor potential ankyrin 1 proteins in trigeminal ganglia. Peripherally restricted cannabinoid pretreatment, but not posttreatment, prevented behavioral and biochemical correlates of GTN-induced sensitization. Low pH-activated and allyl isothiocyanate-activated currents in acutely isolated trigeminal neurons were reversibly attenuated by PRCB application. Long-term GTN treatment significantly enhanced these currents. Long-term sumatriptan treatment also led to the development of allodynia to mechanical and cold stimuli that was slowly reversible after sumatriptan discontinuation. Subsequent challenge with a previously ineffective low-dose GTN (0.1-0.3 mg/kg) revealed latent behavioral sensitization and increased expression of phosphorylated protein kinase A, neuronal nitric oxide synthase, and transient receptor potential ankyrin 1 proteins in trigeminal ganglia. Peripherally restricted cannabinoid pretreatment prevented all behavioral and biochemical correlates of allodynia and latent sensitization. Importantly, long-term PRCB treatment alone did not produce any behavioral or biochemical signs of sensitization. These data validate peripheral cannabinoid receptors as potential therapeutic targets in migraine and medication overuse headache.
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Affiliation(s)
- Toru Yamamoto
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
| | - Yatendra Mulpuri
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
| | - Mikhail Izraylev
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
| | - Qianyi Li
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
| | - Menooa Simonian
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
| | - Christian Kramme
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
| | - Brian L. Schmidt
- Department of Oral & Maxillofacial Surgery and Bluestone Center for Clinical Research, New York University College of Dentistry, New York, NY
| | - Herbert H. Seltzman
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, NC
| | - Igor Spigelman
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA
- Brain Research Institute, University of California, Los Angeles, Los Angeles, CA
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26
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Xiong B, Jin G, Xu Y, You W, Luo Y, Fang M, Chen B, Huang H, Yang J, Lin X, Yu C. Identification of Koumine as a Translocator Protein 18 kDa Positive Allosteric Modulator for the Treatment of Inflammatory and Neuropathic Pain. Front Pharmacol 2021; 12:692917. [PMID: 34248642 PMCID: PMC8264504 DOI: 10.3389/fphar.2021.692917] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/07/2021] [Indexed: 01/08/2023] Open
Abstract
Koumine is an alkaloid that displays notable activity against inflammatory and neuropathic pain, but its therapeutic target and molecular mechanism still need further study. Translocator protein 18 kDa (TSPO) is a vital therapeutic target for pain treatment, and recent research implies that there may be allostery in TSPO. Our previous competitive binding assay hint that koumine may function as a TSPO positive allosteric modulator (PAM). Here, for the first time, we report the pharmacological characterization of koumine as a TSPO PAM. The results imply that koumine might be a high-affinity ligand of TSPO and that it likely acts as a PAM since it could delay the dissociation of 3H-PK11195 from TSPO. Importantly, the allostery was retained in vivo, as koumine augmented Ro5-4864-mediated analgesic and anti-inflammatory effects in several acute and chronic inflammatory and neuropathic pain models. Moreover, the positive allosteric modulatory effect of koumine on TSPO was further demonstrated in cell proliferation assays in T98G human glioblastoma cells. In summary, we have identified and characterized koumine as a TSPO PAM for the treatment of inflammatory and neuropathic pain. Our data lay a solid foundation for the use of the clinical candidate koumine to treat inflammatory and neuropathic pain, further demonstrate the allostery in TSPO, and provide the first proof of principle that TSPO PAM may be a novel avenue for the discovery of analgesics.
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Affiliation(s)
- Bojun Xiong
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
| | - Guilin Jin
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Ying Xu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Wenbing You
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Yufei Luo
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Menghan Fang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Bing Chen
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Huihui Huang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Jian Yang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Xu Lin
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
| | - Changxi Yu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, School of Pharmacy, Fujian Medical University, Fuzhou, China
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27
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Lu J, Yang L, Xu Y, Ai L, Chen J, Xiong F, Hu L, Chen H, Liu J, Yan X, Huang H, Chen L, Yu C. The Modulatory Effect of Motor Cortex Astrocytes on Diabetic Neuropathic Pain. J Neurosci 2021; 41:5287-5302. [PMID: 33753547 PMCID: PMC8211549 DOI: 10.1523/jneurosci.2566-20.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 02/11/2021] [Accepted: 03/11/2021] [Indexed: 02/01/2023] Open
Abstract
Diabetic neuropathic pain (DNP) is a common complication of diabetes characterized by persistent pain. Emerging evidence links astrocytes to mechanical nociceptive processing, and the motor cortex (MCx) is a cerebral cortex region that is known to play a key role in pain regulation. However, the association between MCx astrocytes and DNP pathogenesis remains largely unexplored. Here, we studied this association using designer receptors exclusively activated by designer drugs to specifically manipulate MCx astrocytes. We proved that the selective inhibition of MCx astrocytes reduced DNP in streptozocin (STZ)-induced DNP models and discovered a potential mechanism by which astrocytes release cytokines, including TNF-α and IL-1β, to increase neuronal activation in the MCx, thereby regulating pain. Together, these results demonstrate a pivotal role for MCx astrocytes in DNP pathogenesis and provide new insight into DNP treatment strategies.
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Affiliation(s)
- Jingshan Lu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Lan Yang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Ying Xu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Lijing Ai
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Jian Chen
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Fangfang Xiong
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Lihuan Hu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Huoshu Chen
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Jiyuan Liu
- School of Clinical Medicine, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Xiongbin Yan
- School of Clinical Medicine, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Huihui Huang
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Li Chen
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
- Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, Fujian Medical University, Fuzhou, Fujian 350122, China
| | - Changxi Yu
- Department of Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350122, China
- Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, Fujian Medical University, Fuzhou, Fujian 350122, China
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Cha M, Lee KH, Kwon M, Lee BH. Possible Therapeutic Options for Complex Regional Pain Syndrome. Biomedicines 2021; 9:biomedicines9060596. [PMID: 34074044 PMCID: PMC8225181 DOI: 10.3390/biomedicines9060596] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/18/2021] [Accepted: 05/22/2021] [Indexed: 11/18/2022] Open
Abstract
Complex regional pain syndrome (CRPS) describes an array of painful conditions that are characterized by continuing regional pain. CRPS comprises severe and inappropriate pain in cases of complete recovery after trauma. Research on the pharmacological treatment of CRPS, however, has not been well investigated. In this study, we compared the pain relief effects of different drugs (URB597, pyrrolidine dithiocarbamate, and hydralazine) in a rat model of chronic post-ischemic pain-induced CRPS. After drug injection, CRPS-induced mechanical allodynia was significantly recovered. After three repetitive drug injections, mechanical sensitivity generally improved as hyper-nociception subsided. Reduced Nav1.7 expression at dorsal root ganglions (DRGs) was observed in the drug treatment groups. Neural imaging analysis revealed decreased neural activity for each drug treatment, compared to vehicle. In addition, treatments significantly reduced IL-1β, IL-6, and TNFα expression in DRGs. These results indicated that drugs could reduce the expression of inflammatory factors and alleviate the symptoms of chronic post-ischemic pain-induced CRPS.
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Affiliation(s)
- Myeounghoon Cha
- Department of Physiology, College of Medicine, Yonsei University, Seoul 03722, Korea
- Correspondence: (M.C.); (B.H.L.); Tel.: +82-2-2228-2729 (M.C.)
| | - Kyung Hee Lee
- Department of Dental Hygiene, Division of Health Science, Dongseo University, Busan 47011, Korea;
| | - Minjee Kwon
- Department of Nursing, Kyungil University, Gyeongsan 38428, Korea;
| | - Bae Hwan Lee
- Department of Physiology, College of Medicine, Yonsei University, Seoul 03722, Korea
- Brain Korea 21 PLUS Project for Medical Science, College of Medicine, Yonsei University, Seoul 03722, Korea
- Correspondence: (M.C.); (B.H.L.); Tel.: +82-2-2228-2729 (M.C.)
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Wilkerson JL, Bilbrey JA, Felix JS, Makriyannis A, McMahon LR. Untapped endocannabinoid pharmacological targets: Pipe dream or pipeline? Pharmacol Biochem Behav 2021; 206:173192. [PMID: 33932409 DOI: 10.1016/j.pbb.2021.173192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 04/18/2021] [Accepted: 04/21/2021] [Indexed: 10/21/2022]
Abstract
It has been established that the endogenous cannabinoid (endocannabinoid) system plays key modulatory roles in a wide variety of pathological conditions. The endocannabinoid system comprises both cannabinoid receptors, their endogenous ligands including 2-arachidonoylglycerol (2-AG), N-arachidonylethanolamine (anandamide, AEA), and enzymes that regulate the synthesis and degradation of endogenous ligands which include diacylglycerol lipase alpha (DAGL-α), diacylglycerol lipase beta (DAGL-β), fatty acid amide hydrolase (FAAH), monoacylglycerol lipase (MAGL), α/β hydrolase domain 6 (ABHD6). As the endocannabinoid system exerts considerable involvement in the regulation of homeostasis and disease, much effort has been made towards understanding endocannabinoid-related mechanisms of action at cellular, physiological, and pathological levels as well as harnessing the various components of the endocannabinoid system to produce novel therapeutics. However, drug discovery efforts within the cannabinoid field have been slower than anticipated to reach satisfactory clinical endpoints and raises an important question into the validity of developing novel ligands that therapeutically target the endocannabinoid system. To answer this, we will first examine evidence that supports the existence of an endocannabinoid system role within inflammatory diseases, neurodegeneration, pain, substance use disorders, mood disorders, as well as metabolic diseases. Next, this review will discuss recent clinical studies, within the last 5 years, of cannabinoid compounds in context to these diseases. We will also address some of the challenges and considerations within the cannabinoid field that may be important in the advancement of therapeutics into the clinic.
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Affiliation(s)
- Jenny L Wilkerson
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA.
| | - Joshua A Bilbrey
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - Jasmine S Felix
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - Alexandros Makriyannis
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA; Departments of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA
| | - Lance R McMahon
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA.
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Hermes DJ, Jacobs IR, Key MC, League AF, Yadav-Samudrala BJ, Xu C, McLane VD, Nass SR, Jiang W, Meeker RB, Ignatowska-Jankowska BM, Lichtman AH, Li Z, Wu Z, Yuan H, Knapp PE, Hauser KF, Fitting S. Escalating morphine dosing in HIV-1 Tat transgenic mice with sustained Tat exposure reveals an allostatic shift in neuroinflammatory regulation accompanied by increased neuroprotective non-endocannabinoid lipid signaling molecules and amino acids. J Neuroinflammation 2020; 17:345. [PMID: 33208151 PMCID: PMC7672881 DOI: 10.1186/s12974-020-01971-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 09/29/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Human immunodeficiency virus type-1 (HIV-1) and opiates cause long-term inflammatory insult to the central nervous system (CNS) and worsen disease progression and HIV-1-related neuropathology. The combination of these proinflammatory factors reflects a devastating problem as opioids have high abuse liability and continue to be prescribed for certain patients experiencing HIV-1-related pain. METHODS Here, we examined the impact of chronic (3-month) HIV-1 transactivator of transcription (Tat) exposure to short-term (8-day), escalating morphine in HIV-1 Tat transgenic mice that express the HIV-1 Tat protein in a GFAP promoter-regulated, doxycycline (DOX)-inducible manner. In addition to assessing morphine-induced tolerance in nociceptive responses organized at spinal (i.e., tail-flick) and supraspinal (i.e., hot-plate) levels, we evaluated neuroinflammation via positron emission tomography (PET) imaging using the [18F]-PBR111 ligand, immunohistochemistry, and cytokine analyses. Further, we examined endocannabinoid (eCB) levels, related non-eCB lipids, and amino acids via mass spectrometry. RESULTS: Tat-expressing [Tat(+)] transgenic mice displayed antinociceptive tolerance in the tail withdrawal and hot-plate assays compared to control mice lacking Tat [Tat(-)]. This tolerance was accompanied by morphine-dependent increases in Iba-1 ± 3-nitrotryosine immunoreactive microglia, and alterations in pro- and anti-inflammatory cytokines, and chemokines in the spinal cord and striatum, while increases in neuroinflammation were absent by PET imaging of [18F]-PBR111 uptake. Tat and morphine exposure differentially affected eCB levels, non-eCB lipids, and specific amino acids in a region-dependent manner. In the striatum, non-eCB lipids were significantly increased by short-term, escalating morphine exposure, including peroxisome proliferator activator receptor alpha (PPAR-α) ligands N-oleoyl ethanolamide (OEA) and N-palmitoyl ethanolamide (PEA), as well as the amino acids phenylalanine and proline. In the spinal cord, Tat exposure increased amino acids leucine and valine, while morphine decreased levels of tyrosine and valine but did not affect eCBs or non-eCB lipids. CONCLUSION Overall results demonstrate that 3 months of Tat exposure increased morphine tolerance and potentially innate immune tolerance evidenced by reductions in specific cytokines (e.g., IL-1α, IL-12p40) and microglial reactivity. In contrast, short-term, escalating morphine exposure acted as a secondary stressor revealing an allostatic shift in CNS baseline inflammatory responsiveness from sustained Tat exposure.
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Affiliation(s)
- Douglas J Hermes
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, NC, USA
| | - Ian R Jacobs
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, NC, USA
| | - Megan C Key
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, NC, USA
| | - Alexis F League
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, NC, USA
| | | | - Changqing Xu
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, NC, USA
| | - Virginia D McLane
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Sara R Nass
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Wei Jiang
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA
- Division of Infectious Diseases, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Rick B Meeker
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | | | - Aron H Lichtman
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Zibo Li
- Department of Radiology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Zhanhong Wu
- Department of Radiology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Hong Yuan
- Department of Radiology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Pamela E Knapp
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA, USA
- Department of Anatomy & Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
| | - Kurt F Hauser
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA, USA
- Department of Anatomy & Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
| | - Sylvia Fitting
- Department of Psychology & Neuroscience, University of North Carolina, Chapel Hill, NC, USA.
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Abstract
Pain is an essential protective mechanism that the body uses to alert or prevent further damage. Pain sensation is a complex event involving perception, transmission, processing, and response. Neurons at different levels (peripheral, spinal cord, and brain) are responsible for these pro- or antinociceptive activities to ensure an appropriate response to external stimuli. The terminals of these neurons, both in the peripheral endings and in the synapses, are equipped with G protein-coupled receptors (GPCRs), voltage- and ligand-gated ion channels that sense structurally diverse stimuli and inhibitors of neuronal activity. This review will focus on the largest class of sensory proteins, the GPCRs, as they are distributed throughout ascending and descending neurons and regulate activity at each step during pain transmission. GPCR activation also directly or indirectly controls the function of co-localized ion channels. The levels and types of some GPCRs are significantly altered in different pain models, especially chronic pain states, emphasizing that these molecules could be new targets for therapeutic intervention in chronic pain.
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Affiliation(s)
- Tao Che
- Department of Anesthesiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri 63110, United States.,Center for Clinical Pharmacology, St. Louis College of Pharmacology and Washington University in St. Louis, St. Louis, Missouri 63110, United States
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32
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Kiso T, Watabiki T, Sekizawa T. ASP8477, a fatty acid amide hydrolase inhibitor, exerts analgesic effects in rat models of neuropathic and dysfunctional pain. Eur J Pharmacol 2020; 881:173194. [DOI: 10.1016/j.ejphar.2020.173194] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 12/29/2022]
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Bravo L, Llorca-Torralba M, Suárez-Pereira I, Berrocoso E. Pain in neuropsychiatry: Insights from animal models. Neurosci Biobehav Rev 2020; 115:96-115. [PMID: 32437745 DOI: 10.1016/j.neubiorev.2020.04.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 04/11/2020] [Accepted: 04/23/2020] [Indexed: 02/08/2023]
Abstract
Pain is the most common symptom reported in clinical practice, meaning that it is associated with many pathologies as either the origin or a consequence of other illnesses. Furthermore, pain is a complex emotional and sensorial experience, as the correspondence between pain and body damage varies considerably. While these issues are widely acknowledged in clinical pain research, until recently they have not been extensively considered when exploring animal models, important tools for understanding pain pathophysiology. Interestingly, chronic pain is currently considered a risk factor to suffer psychiatric disorders, mainly stress-related disorders like anxiety and depression. Conversely, pain appears to be altered in many psychiatric disorders, such as depression, anxiety and schizophrenia. Thus, pain and psychiatric disorders have been linked in epidemiological and clinical terms, although the neurobiological mechanisms involved in this pathological bidirectional relationship remain unclear. Here we review the evidence obtained from animal models about the co-morbidity of pain and psychiatric disorders, placing special emphasis on the different dimensions of pain.
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Affiliation(s)
- Lidia Bravo
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, 11003 Cádiz, Spain; Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya 21, 11009 Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Meritxell Llorca-Torralba
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, 11003 Cádiz, Spain; Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya 21, 11009 Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Irene Suárez-Pereira
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, 11003 Cádiz, Spain; Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya 21, 11009 Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Esther Berrocoso
- Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya 21, 11009 Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, 11510 Puerto Real, Cádiz, Spain.
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34
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Rocha L, Cinar R, Guevara-Guzmán R, Alonso-Vanegas M, San-Juan D, Martínez-Juárez I, Castañeda-Cabral JL, Carmona-Cruz F. Endocannabinoid System and Cannabinoid 1 Receptors in Patients With Pharmacoresistant Temporal Lobe Epilepsy and Comorbid Mood Disorders. Front Behav Neurosci 2020; 14:52. [PMID: 32435186 PMCID: PMC7218130 DOI: 10.3389/fnbeh.2020.00052] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 03/20/2020] [Indexed: 12/23/2022] Open
Abstract
Experimental evidence points out that the activation of the endocannabinoid system induces neuroprotective effects and reduces mood disorders. In the hippocampus of patients with mesial temporal lobe epilepsy (MTLE), studies indicated augmented cannabinoid 1 receptor (CB1R) binding, in spite of its low mRNA and protein expressions. Although this situation suggests an enhanced CB1R-induced neurotransmission in patients with MTLE, especially those with pharmacoresistant seizures, which present important neuronal damage and high comorbid mood disorders. The present study focused to investigate the status of CB1R and the endocannabinoid system by obtaining CB1R-induced G-protein signaling efficacy and measuring the tissue levels of endocannabinoids in the hippocampus and the temporal neocortex of patients with pharmacoresistant MTLE. Furthermore, the obtained results were correlated with comorbid anxiety and depression. The experiments revealed that patients with MTLE present increased CB1R-induced G-protein signaling efficacy (Emax) as well as an augmented tissue content of anandamide and oleoylethanolamine and low 2-arachidonoylglycerol. Some of these changes were more evident in patients with MTLE without mood disorders. The current findings indicate that pharmacoresistant MTLE is associated with increased CB1R-induced transductional mechanisms as well as augmented tissue content of specific endocannabinoids in the hippocampus and the temporal neocortex. The enhanced endocannabinoid neurotransmission may be involved in the absence of comorbid mood disorders in some patients with MTLE.
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Affiliation(s)
- Luisa Rocha
- Department of Pharmacobiology, Center of Research and Advanced Studies, Mexico City, Mexico
| | - Resat Cinar
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD, United States
| | | | - Mario Alonso-Vanegas
- National Institute of Neurology and Neurosurgery "Manuel Velasco Suarez", Mexico City, Mexico
| | - Daniel San-Juan
- National Institute of Neurology and Neurosurgery "Manuel Velasco Suarez", Mexico City, Mexico
| | - Iris Martínez-Juárez
- National Institute of Neurology and Neurosurgery "Manuel Velasco Suarez", Mexico City, Mexico
| | | | - Francia Carmona-Cruz
- Department of Pharmacobiology, Center of Research and Advanced Studies, Mexico City, Mexico
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35
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Targeting Peripherally Restricted Cannabinoid Receptor 1, Cannabinoid Receptor 2, and Endocannabinoid-Degrading Enzymes for the Treatment of Neuropathic Pain Including Neuropathic Orofacial Pain. Int J Mol Sci 2020; 21:ijms21041423. [PMID: 32093166 PMCID: PMC7073137 DOI: 10.3390/ijms21041423] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 02/06/2023] Open
Abstract
Neuropathic pain conditions including neuropathic orofacial pain (NOP) are difficult to treat. Contemporary therapeutic agents for neuropathic pain are often ineffective in relieving pain and are associated with various adverse effects. Finding new options for treating neuropathic pain is a major priority in pain-related research. Cannabinoid-based therapeutic strategies have emerged as promising new options. Cannabinoids mainly act on cannabinoid 1 (CB1) and 2 (CB2) receptors, and the former is widely distributed in the brain. The therapeutic significance of cannabinoids is masked by their adverse effects including sedation, motor impairment, addiction and cognitive impairment, which are thought to be mediated by CB1 receptors in the brain. Alternative approaches have been developed to overcome this problem by selectively targeting CB2 receptors, peripherally restricted CB1 receptors and endocannabinoids that may be locally synthesized on demand at sites where their actions are pertinent. Many preclinical studies have reported that these strategies are effective for treating neuropathic pain and produce no or minimal side effects. Recently, we observed that inhibition of degradation of a major endocannabinoid, 2-arachydonoylglycerol, can attenuate NOP following trigeminal nerve injury in mice. This review will discuss the above-mentioned alternative approaches that show potential for treating neuropathic pain including NOP.
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36
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Luo Y, Zhang J, Chen L, Chen SR, Chen H, Zhang G, Pan HL. Histone methyltransferase G9a diminishes expression of cannabinoid CB 1 receptors in primary sensory neurons in neuropathic pain. J Biol Chem 2020; 295:3553-3562. [PMID: 32024693 DOI: 10.1074/jbc.ra119.011053] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/03/2020] [Indexed: 12/14/2022] Open
Abstract
Type 1 cannabinoid receptors (CB1Rs) are expressed in the dorsal root ganglion (DRG) and contribute to the analgesic effect of cannabinoids. However, the epigenetic mechanism regulating the expression of CB1Rs in neuropathic pain is unknown. G9a (encoded by the Ehmt2 gene), a histone 3 at lysine 9 methyltransferase, is a key chromatin regulator responsible for gene silencing. In this study, we determined G9a's role in regulating CB1R expression in the DRG and in CB1R-mediated analgesic effects in an animal model of neuropathic pain. We show that nerve injury profoundly reduced mRNA levels of CB1Rs but increased the expression of CB2 receptors in the rat DRG. ChIP results indicated increased enrichment of histone 3 at lysine 9 dimethylation, a G9a-catalyzed repressive histone mark, at the promoter regions of the CB1R genes. G9a inhibition in nerve-injured rats not only up-regulated the CB1R expression level in the DRG but also potentiated the analgesic effect of a CB1R agonist on nerve injury-induced pain hypersensitivity. Furthermore, in mice lacking Ehmt2 in DRG neurons, nerve injury failed to reduce CB1R expression in the DRG and to decrease the analgesic effect of the CB1R agonist. Moreover, nerve injury diminished the inhibitory effect of the CB1R agonist on synaptic glutamate release from primary afferent nerves to spinal cord dorsal horn neurons in WT mice but not in mice lacking Ehmt2 in DRG neurons. Our findings reveal that nerve injury diminishes the analgesic effect of CB1R agonists through G9a-mediated CB1R down-regulation in primary sensory neurons.
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Affiliation(s)
- Yi Luo
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030; Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, China
| | - Jixiang Zhang
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Lin Chen
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030; School of Physical Education, Jianghan University, Wuhan, Hubei 430056, China
| | - Shao-Rui Chen
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Hong Chen
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Guangfen Zhang
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Hui-Lin Pan
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030.
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37
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Thapa D, Cairns EA, Szczesniak AM, Kulkarni PM, Straiker AJ, Thakur GA, Kelly MEM. Allosteric Cannabinoid Receptor 1 (CB1) Ligands Reduce Ocular Pain and Inflammation. Molecules 2020; 25:E417. [PMID: 31968549 PMCID: PMC7024337 DOI: 10.3390/molecules25020417] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 01/16/2020] [Indexed: 01/08/2023] Open
Abstract
Cannabinoid receptor 1 (CB1) activation has been reported to reduce transient receptor potential cation channel subfamily V member 1 (TRPV1)-induced inflammatory responses and is anti-nociceptive and anti-inflammatory in corneal injury. We examined whether allosteric ligands, can modulate CB1 signaling to reduce pain and inflammation in corneal hyperalgesia. Corneal hyperalgesia was generated by chemical cauterization of cornea in wildtype and CB2 knockout (CB2-/-) mice. The novel racemic CB1 allosteric ligand GAT211 and its enantiomers GAT228 and GAT229 were examined alone or in combination with the orthosteric CB1 agonist Δ8-tetrahydrocannabinol (Δ8-THC). Pain responses were assessed following capsaicin (1 µM) stimulation of injured corneas at 6 h post-cauterization. Corneal neutrophil infiltration was also analyzed. GAT228, but not GAT229 or GAT211, reduced pain scores in response to capsaicin stimulation. Combination treatments of 0.5% GAT229 or 1% GAT211 with subthreshold Δ8-THC (0.4%) significantly reduced pain scores following capsaicin stimulation. The anti-nociceptive effects of both GAT229 and GAT228 were blocked with CB1 antagonist AM251, but remained unaffected in CB2-/- mice. Two percent GAT228, or the combination of 0.2% Δ8-THC with 0.5% GAT229 also significantly reduced corneal inflammation. CB1 allosteric ligands could offer a novel approach for treating corneal pain and inflammation.
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Affiliation(s)
- Dinesh Thapa
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Elizabeth A. Cairns
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | | | - Pushkar M. Kulkarni
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA
| | - Alex J. Straiker
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405, USA
| | - Ganesh A. Thakur
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA
| | - Melanie E. M. Kelly
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada
- Department of Anesthesia, Pain Management & Perioperative Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada
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38
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Milligan AL, Szabo-Pardi TA, Burton MD. Cannabinoid Receptor Type 1 and Its Role as an Analgesic: An Opioid Alternative? J Dual Diagn 2020; 16:106-119. [PMID: 31596190 PMCID: PMC7007359 DOI: 10.1080/15504263.2019.1668100] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Understanding how the body regulates pain is fundamental to develop rational strategies to combat the growing prevalence of chronic pain states, opioid dependency, and the increased financial burden to the medical care system. Pain is the most prominent reason why Americans seek medical attention and extensive literature has identified the importance of the endocannabinoid pathway in controlling pain. Modulation of the endocannabinoid system offers new therapeutic opportunities for the selective control of excessive neuronal activity in several pain conditions (acute, inflammatory, chronic, and neuropathic). Cannabinoids have a long history of medicinal use and their analgesic properties are well documented; however, there are major impediments to understanding cannabinoid pain modulation. One major issue is the presence of psychotropic side effects associated with D9-tetrahydrocannabinol (THC) or synthetic derivatives, which puts an emphatic brake on their use. This dose-limiting effect prevents the appropriate degree of analgesia . Animal studies have shown that the psychotropic effects are mediated via brain cannabinoid type 1 (CB1) receptors, while analgesic activity in chronic pain states may be mediated via CB1R action in the spinal cord, brainstem, peripheral sensory neurons, or immune cells. The development of appropriate therapies is incumbent on our understanding of the role of peripheral versus central endocannabinoid-driven analgesia. Recent physiological, pharmacological, and anatomical studies provide evidence that one of the main roles of the endocannabinoid system is the regulation of gamma-aminobutyric acid (GABA) and/or glutamate release. This article will review this evidence in the context of its implications for pain. We first provide a brief overview of CB1R's role in the regulation of nociception, followed by a review of the evidence that the peripheral endocannabinoid system modulates nociception. We then look in detail at regulation of central-mediated analgesia, followed up with evidence that cannabinoidmediated modulation of pain involves modulation of GABAergic and glutamatergic neurotransmission in key brain regions. Finally, we discuss cannabinoid action on non-neuronal cells in the context of inflammation and direct modulation of neurons. This work stands to reveal long-standing controversies in the cannabinoid analgesia area that have had an impact on failed clinical trials and implementation of therapeutics targeting this system.
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Chiocchetti R, Galiazzo G, Tagliavia C, Stanzani A, Giancola F, Menchetti M, Militerno G, Bernardini C, Forni M, Mandrioli L. Cellular Distribution of Canonical and Putative Cannabinoid Receptors in Canine Cervical Dorsal Root Ganglia. Front Vet Sci 2019; 6:313. [PMID: 31608295 PMCID: PMC6761858 DOI: 10.3389/fvets.2019.00313] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/02/2019] [Indexed: 12/11/2022] Open
Abstract
Growing evidence indicates cannabinoid receptors as potential therapeutic targets for chronic pain. Consequently, there is an increasing interest in developing cannabinoid receptor agonists for treating human and veterinary pain. To better understand the actions of a drug, it is of paramount importance to know the cellular distribution of its specific receptor(s). The distribution of canonical and putative cannabinoid receptors in the peripheral and central nervous system of dogs is still in its infancy. In order to help fill this anatomical gap, the present ex vivo study has been designed to identify the cellular sites of cannabinoid and cannabinoid-related receptors in canine spinal ganglia. In particular, the cellular distribution of the cannabinoid receptors type 1 and 2 (CB1 and CB2) and putative cannabinoid receptors G protein-coupled receptor 55 (GPR55), nuclear peroxisome proliferator-activated receptor alpha (PPARα), and transient receptor potential vanilloid type 1 (TRPV1) have been immunohistochemically investigated in the C6–C8 cervical ganglia of dogs. About 50% of the neuronal population displayed weak to moderate CB1 receptor and TRPV1 immunoreactivity, while all of them were CB2-positive and nearly 40% also expressed GPR55 immunolabeling. Schwann cells, blood vessel smooth muscle cells, and pericyte-like cells all expressed CB2 receptor immunoreactivity, endothelial cell being also PPARα-positive. All the satellite glial cells (SGCs) displayed bright GPR55 receptor immunoreactivity. In half of the study dogs, SGCs were also PPARα-positive, and limited to older dogs displayed TRPV1 immunoreactivity. The present study may represent a morphological substrate to consider in order to develop therapeutic strategies against chronic pain.
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Affiliation(s)
- Roberto Chiocchetti
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Giorgia Galiazzo
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Claudio Tagliavia
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Agnese Stanzani
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Fiorella Giancola
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Marika Menchetti
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Gianfranco Militerno
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Chiara Bernardini
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Monica Forni
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Luciana Mandrioli
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
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40
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Buisseret B, Alhouayek M, Guillemot-Legris O, Muccioli GG. Endocannabinoid and Prostanoid Crosstalk in Pain. Trends Mol Med 2019; 25:882-896. [PMID: 31160168 DOI: 10.1016/j.molmed.2019.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/18/2019] [Accepted: 04/22/2019] [Indexed: 12/31/2022]
Abstract
Interfering with endocannabinoid (eCB) metabolism to increase their levels is a proven anti-nociception strategy. However, because the eCB and prostanoid systems are intertwined, interfering with eCB metabolism will affect the prostanoid system and inversely. Key to this connection is the production of the cyclooxygenase (COX) substrate arachidonic acid upon eCB hydrolysis as well as the ability of COX to metabolize the eCBs anandamide (AEA) and 2-arachidonoylglycerol (2-AG) into prostaglandin-ethanolamides (PG-EA) and prostaglandin-glycerol esters (PG-G), respectively. Recent studies shed light on the role of PG-Gs and PG-EAs in nociception and inflammation. Here, we discuss the role of these complex systems in nociception and new opportunities to alleviate pain by interacting with them.
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Affiliation(s)
- Baptiste Buisseret
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 1200 Bruxelles, Belgium
| | - Mireille Alhouayek
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 1200 Bruxelles, Belgium
| | - Owein Guillemot-Legris
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 1200 Bruxelles, Belgium
| | - Giulio G Muccioli
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 1200 Bruxelles, Belgium.
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41
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Zhu H, Xiang HC, Li HP, Lin LX, Hu XF, Zhang H, Meng WY, Liu L, Chen C, Shu Y, Zhang RY, Zhang P, Si JQ, Li M. Inhibition of GABAergic Neurons and Excitation of Glutamatergic Neurons in the Ventrolateral Periaqueductal Gray Participate in Electroacupuncture Analgesia Mediated by Cannabinoid Receptor. Front Neurosci 2019; 13:484. [PMID: 31156369 PMCID: PMC6533898 DOI: 10.3389/fnins.2019.00484] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/29/2019] [Indexed: 01/26/2023] Open
Abstract
Although electroacupuncture (EA) has become a worldwide practice, little is understood about its precise target in the central nervous system (CNS) and the cell type-specific analgesia mechanism. In the present study, we found that EA has significant antinociceptive effects both in inflammatory and neuropathic pain models. Chemogenetic inhibition of GABAergic neurons in the ventrolateral periaqueductal gray (vlPAG) replicated the effects of EA, whereas the combination of chemogenetic activation of GABAergic neurons and chemogenetic inhibition of glutamatergic neurons in the vlPAG was needed to reverse the effects of EA. Specifically knocking out CB1 receptors on GABAergic neurons in the vlPAG abolished the EA effect on pain hypersensitivity, while specifically knocking out CB1 receptors on glutamatergic neurons attenuated only a small portion of the EA effect. EA synchronously inhibits GABAergic neurons and activates glutamatergic neurons in the vlPAG through CB1 receptors to produce EA-induced analgesia. The CB1 receptors on GABAergic neurons localized in the vlPAG was the basis of the EA effect on pain hypersensitivity. This study provides new experimental evidence that EA can bidirectionally regulate GABAergic neurons and glutamatergic neurons via the CB1 receptors of the vlPAG to produce analgesia effects.
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Affiliation(s)
- He Zhu
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China.,Department of Physiology, Medical College of Shihezi University, Shihezi, China
| | - Hong-Chun Xiang
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Hong-Ping Li
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Li-Xue Lin
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Xue-Fei Hu
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Hong Zhang
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Wang-Yang Meng
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Lu Liu
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Chao Chen
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Yang Shu
- Department of Central Laboratory, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Ru-Yue Zhang
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Pei Zhang
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Jun-Qiang Si
- Department of Physiology, Medical College of Shihezi University, Shihezi, China
| | - Man Li
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Ministry of Education, School of Basic Medicine, The Institute of Brain Research, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
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42
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Noroozi M, Doroudian MR, Sarkouhi A, nejad MA, Barkhori A, Moghadari M, Shaabani M. Synergistic effects of Paracetamol and Dexamethasone with Lidocaine in Intravenous regional anesthesia (IVRA) of upper limbs: A randomized clinical trial. EGYPTIAN JOURNAL OF ANAESTHESIA 2019. [DOI: 10.1016/j.egja.2015.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Mehrdad Noroozi
- Department of Anesthesiology, Kerman University of Medical Sciences, Iran
| | | | - Ali Sarkouhi
- Department of Anesthesiology, Kerman University of Medical Sciences, Iran
| | - Mehdi Ahmadi nejad
- Department of Anesthesiology, Kerman University of Medical Sciences, Iran
| | - Ali Barkhori
- Department of Anesthesiology, Kerman University of Medical Sciences, Iran
| | - Masoud Moghadari
- Center for Clinical Research, Shahid Bahonar Hospital, Kerman, Iran
| | - Mohammad Shaabani
- Department of Anesthesiology, Kerman University of Medical Sciences, Iran
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Glare P, Aubrey KR, Myles PS. Transition from acute to chronic pain after surgery. Lancet 2019; 393:1537-1546. [PMID: 30983589 DOI: 10.1016/s0140-6736(19)30352-6] [Citation(s) in RCA: 407] [Impact Index Per Article: 81.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 10/20/2018] [Accepted: 02/07/2019] [Indexed: 12/14/2022]
Abstract
Over the past decade there has been an increasing reliance on strong opioids to treat acute and chronic pain, which has been associated with a rising epidemic of prescription opioid misuse, abuse, and overdose-related deaths. Deaths from prescription opioids have more than quadrupled in the USA since 1999, and this pattern is now occurring globally. Inappropriate opioid prescribing after surgery, particularly after discharge, is a major cause of this problem. Chronic postsurgical pain, occurring in approximately 10% of patients who have surgery, typically begins as acute postoperative pain that is difficult to control, but soon transitions into a persistent pain condition with neuropathic features that are unresponsive to opioids. Research into how and why this transition occurs has led to a stronger appreciation of opioid-induced hyperalgesia, use of more effective and safer opioid-sparing analgesic regimens, and non-pharmacological interventions for pain management. This Series provides an overview of the epidemiology and societal effect, basic science, and current recommendations for managing persistent postsurgical pain. We discuss the advances in the prevention of this transitional pain state, with the aim to promote safer analgesic regimens to better manage patients with acute and chronic pain.
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Affiliation(s)
- Paul Glare
- Pain Management Research Institute, University of Sydney, Sydney, NSW, Australia
| | - Karin R Aubrey
- Pain Management Research Institute, University of Sydney, Sydney, NSW, Australia; Kolling Institute, Royal North Shore Hospital, St Leonards, NSW, Australia
| | - Paul S Myles
- Department of Anaesthesiology and Perioperative Medicine, Alfred Hospital, Melbourne, VIC.
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Long-term application of cannabinoids leads to dissociation between changes in cAMP and modulation of GABA A receptors of mouse trigeminal sensory neurons. Neurochem Int 2019; 126:74-85. [PMID: 30633953 DOI: 10.1016/j.neuint.2019.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/20/2018] [Accepted: 01/07/2019] [Indexed: 12/11/2022]
Abstract
Antinociception caused by cannabinoids may have a partial peripheral origin in addition to its central site of action. In fact, we have observed that anandamide selectively and reversibly inhibits GABAA receptors of putative nociceptive neurons of mouse trigeminal sensory ganglia via CB1 receptor activation to inhibit adenylyl cyclase and decrease cAMP with downstream posttranslational alterations. Since cannabinoids are often used chronically, we studied changes in cAMP levels and GABA-mediated currents of trigeminal neurons following 24 h application of anandamide (0.5 μM) or the synthetic cannabinoid WIN 55,212-2 (5 μM). With this protocol GABA responses were similar to control despite persistent fall in cAMP levels. Inhibition by WIN 55,212-2 of GABA effects recovered after 30 min washout and was not associated with changes in CB1 receptor expression, indicating lack of CB1 receptor inactivation and transient loss of negative coupling between CB1 receptors and GABAA receptors. The phosphodiesterase inhibitor rolipram (100 μM; 24 h) enhanced cAMP levels and GABA-mediated currents, suggesting GABAA receptors were sensitive to persistent upregulation via cAMP. While the adenylyl cyclase activator forskolin (1-20 μM) facilitated cAMP levels and GABA currents following 30 min application, this action was lost after 24 h in line with the drug limited lifespan. The PKA inhibitor PKI 14-22 (10 μM) increased cAMP without changing GABA currents. These data indicate that modulation of GABAA receptors by intracellular cAMP could be lost following persistent application of cannabinoids. Thus, these observations provide an insight into the waning antinociceptive effects of these compounds.
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45
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Jones M, Wen J, Selvaraj P, Tanaka M, Moran S, Zhang Y. Therapeutic Effect of the Substrate-Selective COX-2 Inhibitor IMMA in the Animal Model of Chronic Constriction Injury. Front Pharmacol 2018; 9:1481. [PMID: 30618769 PMCID: PMC6305478 DOI: 10.3389/fphar.2018.01481] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/03/2018] [Indexed: 01/09/2023] Open
Abstract
Enhancement of endocannabinoid signaling has emerged as an attractive strategy for the treatment of pain. In addition to the well-characterized hydrolytic pathways, cyclooxygenase-2 (COX-2) mediated oxygenation is thought to be an alternative route for endocannabinoid metabolism and therefore provides a new avenue for drug intervention. In this study, we examined the therapeutic effect of indomethacin morpholinamide (IMMA), a novel substrate-selective COX-2 inhibitor, in the chronic constriction injury (CCI) mouse model. Treatment with IMMA significantly alleviated hyperalgesia and mechanical allodynia demonstrated by increased thermal withdrawal latency in Hargreaves test and tactile thresholds in Von Frey test. Accumulation of astrocytes and microglia in spinal cord dorsal horn and infiltration of macrophages into the dorsal root ganglion and sciatic nerve were reduced by drug treatment. Co-administration of the CB2 receptor antagonist, but not the CB1 receptor antagonist partially reversed the inhibitory effect of IMMA on pain sensitivity and inflammatory infiltrates. IMMA downregulated the mRNA expression of TNF-α and IL-1β and the production of IL-6 and MCP-1 proteins in the ipsilateral sciatic nerve. The enhanced NF-κB DNA binding activity in the CCI mouse dorsal spinal cord was also significantly reduced, suggesting that inactivation of NF-κB contributes to the anti-inflammatory property of IMMA. However, different from the previous reports showing that IMMA can increase endocannabinoids without interfering with arachidonic acid metabolism, treatment with IMMA failed to elevate the endogenous levels of AEA and 2-AG, but significantly reduced the production of prostaglandin E2 (PGE2). Furthermore, the mRNA expression of enzymes involved in PGE2 production, COX-2 and prostaglandin E synthase 2 in the ipsilateral sciatic nerve was also suppressed by IMMA treatment. Taken together, these results suggested that IMMA might exert anti-nociceptive effects through multiple mechanisms which include, but are not limited to, CB2 receptor activation and reduced PGE2 production.
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Affiliation(s)
- Melissa Jones
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Jie Wen
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Prabhuanand Selvaraj
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Mikiei Tanaka
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Sean Moran
- Biomedical Instrumentation Center, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Yumin Zhang
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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46
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Vučković S, Srebro D, Vujović KS, Vučetić Č, Prostran M. Cannabinoids and Pain: New Insights From Old Molecules. Front Pharmacol 2018; 9:1259. [PMID: 30542280 PMCID: PMC6277878 DOI: 10.3389/fphar.2018.01259] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/15/2018] [Indexed: 01/11/2023] Open
Abstract
Cannabis has been used for medicinal purposes for thousands of years. The prohibition of cannabis in the middle of the 20th century has arrested cannabis research. In recent years there is a growing debate about the use of cannabis for medical purposes. The term ‘medical cannabis’ refers to physician-recommended use of the cannabis plant and its components, called cannabinoids, to treat disease or improve symptoms. Chronic pain is the most commonly cited reason for using medical cannabis. Cannabinoids act via cannabinoid receptors, but they also affect the activities of many other receptors, ion channels and enzymes. Preclinical studies in animals using both pharmacological and genetic approaches have increased our understanding of the mechanisms of cannabinoid-induced analgesia and provided therapeutical strategies for treating pain in humans. The mechanisms of the analgesic effect of cannabinoids include inhibition of the release of neurotransmitters and neuropeptides from presynaptic nerve endings, modulation of postsynaptic neuron excitability, activation of descending inhibitory pain pathways, and reduction of neural inflammation. Recent meta-analyses of clinical trials that have examined the use of medical cannabis in chronic pain present a moderate amount of evidence that cannabis/cannabinoids exhibit analgesic activity, especially in neuropathic pain. The main limitations of these studies are short treatment duration, small numbers of patients, heterogeneous patient populations, examination of different cannabinoids, different doses, the use of different efficacy endpoints, as well as modest observable effects. Adverse effects in the short-term medical use of cannabis are generally mild to moderate, well tolerated and transient. However, there are scant data regarding the long-term safety of medical cannabis use. Larger well-designed studies of longer duration are mandatory to determine the long-term efficacy and long-term safety of cannabis/cannabinoids and to provide definitive answers to physicians and patients regarding the risk and benefits of its use in the treatment of pain. In conclusion, the evidence from current research supports the use of medical cannabis in the treatment of chronic pain in adults. Careful follow-up and monitoring of patients using cannabis/cannabinoids are mandatory.
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Affiliation(s)
- Sonja Vučković
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Dragana Srebro
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Katarina Savić Vujović
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Čedomir Vučetić
- Clinic of Orthopaedic Surgery and Traumatology, Clinical Center of Serbia, Belgrade, Serbia.,Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Milica Prostran
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
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47
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Slivicki RA, Saberi SA, Iyer V, Vemuri VK, Makriyannis A, Hohmann AG. Brain-Permeant and -Impermeant Inhibitors of Fatty Acid Amide Hydrolase Synergize with the Opioid Analgesic Morphine to Suppress Chemotherapy-Induced Neuropathic Nociception Without Enhancing Effects of Morphine on Gastrointestinal Transit. J Pharmacol Exp Ther 2018; 367:551-563. [PMID: 30275151 DOI: 10.1124/jpet.118.252288] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 09/28/2018] [Indexed: 01/15/2023] Open
Abstract
Opioid-based therapies remain a mainstay for chronic pain management, but unwanted side effects limit therapeutic use. We compared efficacies of brain-permeant and -impermeant inhibitors of fatty acid amide hydrolase (FAAH) in suppressing neuropathic pain induced by the chemotherapeutic agent paclitaxel. Paclitaxel produced mechanical and cold allodynia without altering nestlet shredding or marble burying behaviors. We compared FAAH inhibitors that differ in their ability to penetrate the central nervous system for antiallodynic efficacy, pharmacological specificity, and synergism with the opioid analgesic morphine. (3'-(aminocarbonyl)[1,1'-biphenyl]- 3-yl)-cyclohexylcarbamate (URB597), a brain-permeant FAAH inhibitor, attenuated paclitaxel-induced allodynia via cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2) mechanisms. URB937, a brain-impermeant FAAH inhibitor, suppressed paclitaxel-induced allodynia through a CB1 mechanism only. 5-[4-(4-cyano-1-butyn-1-yl)phenyl]-1-(2,4-dichlorophenyl)-N-(1,1-dioxido-4-thiomorpholinyl)-4-methyl-1H-pyrazole-3-carboxamide (AM6545), a peripherally restricted CB1 antagonist, fully reversed the antiallodynic efficacy of N-cyclohexyl-carbamic acid, 3'-(aminocarbonyl)-6-hydroxy[1,1'- biphenyl]-3-yl ester (URB937) but only partially reversed that of URB597. Thus, URB937 suppressed paclitaxel-induced allodynia through a mechanism that was dependent upon peripheral CB1 receptor activation only. Antiallodynic effects of both FAAH inhibitors were reversed by N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251). Antiallodynic effects of URB597, but not URB937, were reversed by 6-iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-yl](4-methoxyphenyl)methanone (AM630). Isobolographic analysis revealed synergistic interactions between morphine and either URB597 or URB937 in reducing paclitaxel-induced allodynia. A leftward shift in the dose-response curve of morphine antinociception was observed when morphine was coadministered with either URB597 or URB937, consistent with morphine sparing. However, neither URB937 nor URB597 enhanced morphine-induced deficits in colonic transit. Thus, our findings suggest that FAAH inhibition may represent a therapeutic avenue to reduce the overall amount of opioid needed for treating neuropathic pain with potential to reduce unwanted side effects that accompany opioid administration.
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Affiliation(s)
- Richard A Slivicki
- Program in Neuroscience (R.A.S., V.I., A.G.H.), Department of Psychological and Brain Sciences (R.A.S., S.A.S., V.I., A.G.H.), and Gill Center for Biomolecular Science (A.G.H.), Indiana University, Bloomington, Indiana; and Center for Drug Discovery, Northeastern University, Boston, Massachusetts (V.K.V., A.M.)
| | - Shahin A Saberi
- Program in Neuroscience (R.A.S., V.I., A.G.H.), Department of Psychological and Brain Sciences (R.A.S., S.A.S., V.I., A.G.H.), and Gill Center for Biomolecular Science (A.G.H.), Indiana University, Bloomington, Indiana; and Center for Drug Discovery, Northeastern University, Boston, Massachusetts (V.K.V., A.M.)
| | - Vishakh Iyer
- Program in Neuroscience (R.A.S., V.I., A.G.H.), Department of Psychological and Brain Sciences (R.A.S., S.A.S., V.I., A.G.H.), and Gill Center for Biomolecular Science (A.G.H.), Indiana University, Bloomington, Indiana; and Center for Drug Discovery, Northeastern University, Boston, Massachusetts (V.K.V., A.M.)
| | - V Kiran Vemuri
- Program in Neuroscience (R.A.S., V.I., A.G.H.), Department of Psychological and Brain Sciences (R.A.S., S.A.S., V.I., A.G.H.), and Gill Center for Biomolecular Science (A.G.H.), Indiana University, Bloomington, Indiana; and Center for Drug Discovery, Northeastern University, Boston, Massachusetts (V.K.V., A.M.)
| | - Alexandros Makriyannis
- Program in Neuroscience (R.A.S., V.I., A.G.H.), Department of Psychological and Brain Sciences (R.A.S., S.A.S., V.I., A.G.H.), and Gill Center for Biomolecular Science (A.G.H.), Indiana University, Bloomington, Indiana; and Center for Drug Discovery, Northeastern University, Boston, Massachusetts (V.K.V., A.M.)
| | - Andrea G Hohmann
- Program in Neuroscience (R.A.S., V.I., A.G.H.), Department of Psychological and Brain Sciences (R.A.S., S.A.S., V.I., A.G.H.), and Gill Center for Biomolecular Science (A.G.H.), Indiana University, Bloomington, Indiana; and Center for Drug Discovery, Northeastern University, Boston, Massachusetts (V.K.V., A.M.)
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48
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Mulpuri Y, Marty VN, Munier JJ, Mackie K, Schmidt BL, Seltzman HH, Spigelman I. Synthetic peripherally-restricted cannabinoid suppresses chemotherapy-induced peripheral neuropathy pain symptoms by CB1 receptor activation. Neuropharmacology 2018; 139:85-97. [PMID: 29981335 PMCID: PMC6883926 DOI: 10.1016/j.neuropharm.2018.07.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/04/2018] [Accepted: 07/02/2018] [Indexed: 01/19/2023]
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) is a severe and dose-limiting side effect of cancer treatment that affects millions of cancer survivors throughout the world and current treatment options are extremely limited by their side effects. Cannabinoids are highly effective in suppressing pain symptoms of chemotherapy-induced and other peripheral neuropathies but their widespread use is limited by central nervous system (CNS)-mediated side effects. Here, we tested one compound from a series of recently developed synthetic peripherally restricted cannabinoids (PRCBs) in a rat model of cisplatin-induced peripheral neuropathy. Results show that local or systemic administration of 4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3-yl]ethyl}morpholine (PrNMI) dose-dependently suppressed CIPN mechanical and cold allodynia. Orally administered PrNMI also dose-dependently suppressed CIPN allodynia symptoms in both male and female rats without any CNS side effects. Co-administration with selective cannabinoid receptor subtype blockers revealed that PrNMI's anti-allodynic effects are mediated by CB1 receptor (CB1R) activation. Expression of CB2Rs was reduced in dorsal root ganglia from CIPN rats, whereas expression of CB1Rs and various endocannabinoid synthesizing and metabolizing enzymes was unaffected. Daily PrNMI treatment of CIPN rats for two weeks showed a lack of appreciable tolerance to PrNMI's anti-allodynic effects. In an operant task which reflects cerebral processing of pain, PrNMI also dose-dependently suppressed CIPN pain behaviors. Our results demonstrate that PRCBs exemplified by PrNMI may represent a viable option for the treatment of CIPN pain symptoms.
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MESH Headings
- Analgesics, Non-Narcotic/administration & dosage
- Animals
- Antineoplastic Agents/adverse effects
- Cannabinoid Receptor Modulators/administration & dosage
- Cannabinoids/administration & dosage
- Cisplatin/adverse effects
- Cold Temperature
- Dose-Response Relationship, Drug
- Drug Tolerance
- Female
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Ganglia, Spinal/pathology
- Gene Expression Regulation/drug effects
- Hyperalgesia/drug therapy
- Hyperalgesia/metabolism
- Hyperalgesia/pathology
- Male
- Peripheral Nervous System Diseases/chemically induced
- Peripheral Nervous System Diseases/metabolism
- Peripheral Nervous System Diseases/pathology
- RNA, Messenger/metabolism
- Rats, Sprague-Dawley
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/metabolism
- Touch
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Affiliation(s)
- Yatendra Mulpuri
- Laboratory of Neuropharmacology, Division of Oral Biology & Medicine, University of California, Los Angeles, CA, USA
| | - Vincent N Marty
- Laboratory of Neuropharmacology, Division of Oral Biology & Medicine, University of California, Los Angeles, CA, USA
| | - Joseph J Munier
- Laboratory of Neuropharmacology, Division of Oral Biology & Medicine, University of California, Los Angeles, CA, USA
| | - Ken Mackie
- Department of Psychological & Brain Sciences, Indiana University, Bloomington, IN, USA
| | - Brian L Schmidt
- Department of Oral & Maxillofacial Surgery and Bluestone Center for Clinical Research, New York University College of Dentistry, New York, NY, USA
| | - Herbert H Seltzman
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, NC, USA
| | - Igor Spigelman
- Laboratory of Neuropharmacology, Division of Oral Biology & Medicine, University of California, Los Angeles, CA, USA.
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49
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Jin GL, Yue RC, He SD, Hong LM, Xu Y, Yu CX. Koumine Decreases Astrocyte-Mediated Neuroinflammation and Enhances Autophagy, Contributing to Neuropathic Pain From Chronic Constriction Injury in Rats. Front Pharmacol 2018; 9:989. [PMID: 30214411 PMCID: PMC6125371 DOI: 10.3389/fphar.2018.00989] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 08/10/2018] [Indexed: 01/23/2023] Open
Abstract
Koumine, an indole alkaloid, is a major bioactive component of Gelsemium elegans. Previous studies have demonstrated that koumine has noticeable anti-inflammatory and analgesic effects in inflammatory and neuropathic pain (NP) models, but the mechanisms involved are not well understood. This study was designed to explore the analgesic effect of koumine on chronic constriction injury (CCI)-induced NP in rats and the underlying mechanisms, including astrocyte autophagy and apoptosis in the spinal cord. Rats with CCI-induced NP were used to evaluate the analgesic and anti-inflammatory effects of koumine. Lipopolysaccharide (LPS)-induced inflammation in rat primary astrocytes was also used to evaluate the anti-inflammatory effect of koumine. We found that repeated treatment with koumine significantly reduced and inhibited CCI-evoked astrocyte activation as well as the levels of pro-inflammatory cytokines. Meanwhile, we found that koumine promoted autophagy in the spinal cord of CCI rats, as reflected by decreases in the LC3-II/I ratio and P62 expression. Double immunofluorescence staining showed a high level of colocalization between LC3 and GFAP-positive glia cells, which could be decreased by koumine. Intrathecal injection of an autophagy inhibitor (chloroquine) reversed the analgesic effect of koumine, as well as the inhibitory effect of koumine on astrocyte activation in the spinal cord. In addition, TUNEL staining suggested that CCI-induced apoptosis was inhibited by koumine, and this inhibition could be abolished by chloroquine. Western blot analysis revealed that koumine significantly increased the level of Bcl-xl while inhibiting Bax expression and decreasing cleaved caspase-3. In addition, we found that koumine could decrease astrocyte-mediated neuroinflammation and enhance autophagy in primary cultured astrocytes. These results suggest that the analgesic effects of koumine on CCI-induced NP may involve inhibition of astrocyte activation and pro-inflammatory cytokine release, which may relate to the promotion of astrocyte autophagy and the inhibition for apoptosis in the spinal cord.
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Affiliation(s)
- Gui-Lin Jin
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Rong-Cai Yue
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Sai-di He
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Li-Mian Hong
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Ying Xu
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Chang-Xi Yu
- Department of Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China.,Fujian Key Laboratory of Natural Medicine Pharmacology, College of Pharmacy, Fujian Medical University, Fuzhou, China
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50
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The analgesic effect and possible mechanisms by which koumine alters type II collagen-induced arthritis in rats. J Nat Med 2018; 73:217-225. [DOI: 10.1007/s11418-018-1229-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 07/20/2018] [Indexed: 01/28/2023]
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