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Quintero JM, Diaz LE, Galve-Roperh I, Bustos RH, Leon MX, Beltran S, Dodd S. The endocannabinoid system as a therapeutic target in neuropathic pain: a review. Expert Opin Ther Targets 2024:1-17. [PMID: 39317147 DOI: 10.1080/14728222.2024.2407824] [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: 03/06/2024] [Accepted: 09/19/2024] [Indexed: 09/26/2024]
Abstract
INTRODUCTION This review highlights the critical role of the endocannabinoid system (ECS) in regulating neuropathic pain and explores the therapeutic potential of cannabinoids. Understanding the mechanisms of the ECS, including its receptors, endogenous ligands, and enzymatic routes, can lead to innovative treatments for chronic pain, offering more effective therapies for neuropathic conditions. This review bridges the gap between preclinical studies and clinical applications by emphasizing ECS modulation for better pain management outcomes. AREAS COVERED A review mapped the existing literature on neuropathic pain and the effects of modulating the ECS using natural and synthetic cannabinoids. This analysis examined ECS components and their alterations in neuropathic pain, highlighting the peripheral, spinal, and supraspinal mechanisms. This review aimed to provide a thorough understanding of the therapeutic potential of cannabinoids in the management of neuropathic pain. EXPERT OPINION Advances in cannabinoid research have shown significant potential for the management of chronic neuropathic pain. The study emphasizes the need for high-quality clinical trials and collaborative efforts among researchers, clinicians, and regulatory bodies to ensure safe and effective integration of cannabinoids into pain management protocols. Understanding the mechanisms and optimizing cannabinoid formulations and delivery methods are crucial for enhancing therapeutic outcomes.
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Affiliation(s)
- Jose-Manuel Quintero
- Department of Clinical Pharmacology, Evidence-Based Therapeutics Group, Faculty of Medicine, Universidad de La Sabana and Clínica Universidad de La Sabana, Chía, Cundinamarca, Colombia
- Doctoral Programme of Biosciences, Universidad de La Sabana, Chía, Colombia
| | | | - Ismael Galve-Roperh
- Department of Biochemistry and Molecular Biology, School of Chemistry and Instituto de Investigación en Neuroquímica, Complutense University, Madrid, Spain
- Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS) and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Rosa-Helena Bustos
- Department of Clinical Pharmacology, Evidence-Based Therapeutics Group, Faculty of Medicine, Universidad de La Sabana and Clínica Universidad de La Sabana, Chía, Cundinamarca, Colombia
| | - Marta-Ximena Leon
- Grupo Dolor y Cuidados Paliativos, Universidad de La Sabana, Chía, Colombia
| | | | - Seetal Dodd
- Faculty of Medicine, Universidad de La Sabana, Chía, Colombia
- IMPACT - The Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Deakin University, Barwon Health, Geelong, Australia
- Centre for Youth Mental Health, University of Melbourne, Parkville, Australia
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Bartkowiak-Wieczorek J, Bienert A, Czora-Poczwardowska K, Kujawski R, Szulc M, Mikołajczak P, Wizner AM, Jamka M, Hołysz M, Wielgus K, Słomski R, Mądry E. Cannabis sativa L. Extract Alleviates Neuropathic Pain and Modulates CB1 and CB2 Receptor Expression in Rat. Biomolecules 2024; 14:1065. [PMID: 39334832 DOI: 10.3390/biom14091065] [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: 07/25/2024] [Revised: 08/22/2024] [Accepted: 08/23/2024] [Indexed: 09/30/2024] Open
Abstract
INTRODUCTION Cannabis sativa L. (CSL) extract has pain-relieving potential due to its cannabinoid content, so the effects of two CSL extracts on alleviating neuropathic pain were investigated in vivo. Methods and groups: Male Wistar rats (n = 130) were divided into groups and received vincristine (0.1 mg/kg) and gabapentin (60 mg/kg) to induce and relieve neuropathic pain or CSL extracts (D and B). The mRNA and protein expression of the cannabinoid receptors type 1 and 2 (CB1R, CB2R) were evaluated in the cerebral cortex, hippocampus, and lymphocytes. Behavioural tests (Tail-Flick and von Frey) were performed on all animals. RESULTS VK-induced neuropathic pain was accompanied by decreased CB1R protein level and CB2R mRNA expression in the cortex. Gabapentin relieved pain and increased CB1R protein levels in the hippocampus compared to the vincristine group. Hippocampus CB1R protein expression increased with the administration of extract D (10 mg/kg, 40 mg/kg) and extract B (7.5 mg/kg, 10 mg/kg) compared to VK group. In the cerebral cortex CSL decreased CB1R protein expression (10 mg/kg, 20 mg/kg, 40 mg/kg of extract B) and mRNA level (5 mg/kg, 7.5 mg/kg of extract B; 20 mg/kg of extract D) compared to the VK-group.CB2R protein expression increased in the hippocampus after treatment with extract B (7.5 mg/kg) compared to the VK-group. In the cerebral cortex extract B (10 mg/kg, 20 mg/kg) increased CB2R protein expression compared to VK-group. CONCLUSION Alterations in cannabinoid receptor expression do not fully account for the observed behavioural changes in rats. Therefore, additional signalling pathways may contribute to the initiation and transmission of neuropathic pain. The Cannabis extracts tested demonstrated antinociceptive effects comparable to gabapentin, highlighting the antinociceptive properties of Cannabis extracts for human use.
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Affiliation(s)
| | - Agnieszka Bienert
- Department of Clinical Pharmacy and Biopharmacy, Poznan University of Medical Sciences, 60-781 Poznan, Poland
| | | | - Radosław Kujawski
- Department of Pharmacology, Poznan University of Medical Sciences, 60-806 Poznan, Poland
| | - Michał Szulc
- Department of Pharmacology, Poznan University of Medical Sciences, 60-806 Poznan, Poland
| | - Przemysław Mikołajczak
- Department of Pharmacology, Poznan University of Medical Sciences, 60-806 Poznan, Poland
| | - Anna-Maria Wizner
- Department of Clinical Pharmacy and Biopharmacy, Poznan University of Medical Sciences, 60-781 Poznan, Poland
| | - Małgorzata Jamka
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, 60-572 Poznan, Poland
| | - Marcin Hołysz
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, 60-781 Poznan, Poland
| | - Karolina Wielgus
- Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, 60-572 Poznan, Poland
| | - Ryszard Słomski
- Department of Biotechnology, Institute of Natural Fibres and Medicinal Plants National Research Institute, 60-630 Poznan, Poland
| | - Edyta Mądry
- Physiology Department, Poznan University of Medical Sciences, 60-781 Poznan, Poland
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Zhang Y, Li T, Zhao H, Xiao X, Hu X, Wang B, Huang Y, Yin Z, Zhong Y, Li Y, Li J. High-sensitive sensory neurons exacerbate rosacea-like dermatitis in mice by activating γδ T cells directly. Nat Commun 2024; 15:7265. [PMID: 39179539 PMCID: PMC11344132 DOI: 10.1038/s41467-024-50970-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 07/26/2024] [Indexed: 08/26/2024] Open
Abstract
Rosacea patients show facial hypersensitivity to stimulus factors (such as heat and capsaicin); however, the underlying mechanism of this hyperresponsiveness remains poorly defined. Here, we show capsaicin stimulation in mice induces exacerbated rosacea-like dermatitis but has no apparent effect on normal skin. Nociceptor ablation substantially reduces the hyperresponsiveness of rosacea-like dermatitis. Subsequently, we find that γδ T cells express Ramp1, the receptor of the neuropeptide CGRP, and are in close contact with these nociceptors in the skin. γδ T cells are significantly increased in rosacea skin lesions and can be further recruited and activated by neuron-secreted CGRP. Rosacea-like dermatitis is reduced in T cell receptor δ-deficient (Tcrd-/-) mice, and the nociceptor-mediated aggravation of rosacea-like dermatitis is also reduced in these mice. In vitro experiments show that CGRP induces IL17A secretion from γδ T cells by regulating inflammation-related and metabolism-related pathways. Finally, rimegepant, a CGRP receptor antagonist, shows efficacy in the treatment of rosacea-like dermatitis. In conclusion, our findings demonstrate a neuron-CGRP-γδT cell axis that contributes to the hyperresponsiveness of rosacea, thereby showing that targeting CGRP is a potentially effective therapeutic strategy for rosacea.
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MESH Headings
- Animals
- Rosacea/immunology
- Mice
- Calcitonin Gene-Related Peptide/metabolism
- Sensory Receptor Cells/metabolism
- Capsaicin/pharmacology
- Receptors, Antigen, T-Cell, gamma-delta/metabolism
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Skin/pathology
- Skin/immunology
- Skin/metabolism
- Interleukin-17/metabolism
- Interleukin-17/immunology
- Mice, Knockout
- Mice, Inbred C57BL
- Dermatitis/immunology
- Dermatitis/metabolism
- Dermatitis/pathology
- Disease Models, Animal
- Male
- Nociceptors/metabolism
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- Humans
- Receptors, Calcitonin Gene-Related Peptide/metabolism
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Affiliation(s)
- Yiya Zhang
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, P.R. China
| | - Tao Li
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Han Zhao
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Xin Xiao
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Ximin Hu
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Ben Wang
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Yingxue Huang
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhinan Yin
- Guangdong Provincial Key Laboratory of Tumor Interventional Diagnosis and Treatment, Zhuhai Institute of Translational Medicine Zhuhai People's Hospital Affiliated with Jinan University, Jinan University, Zhuhai, Guangdong, China
- The Biomedical Translational Research Institute, Health Science Center (School of Medicine), Jinan University, Guangzhou, Guangdong, China
| | - Yun Zhong
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China
| | - Yangfan Li
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China.
- Department of Dermatology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
| | - Ji Li
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.
- Hunan key laboratory of aging biology, Xiangya Hospital, Central South University, Changsha, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, P.R. China.
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Zeng X, Zheng X, Wu J, Dong H, Zhang J. Assessment of the molecular mechanism in fish using eugenol as anesthesia based on network pharmacology. FISH PHYSIOLOGY AND BIOCHEMISTRY 2024:10.1007/s10695-024-01382-x. [PMID: 39042183 DOI: 10.1007/s10695-024-01382-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 07/14/2024] [Indexed: 07/24/2024]
Abstract
Eugenol is a commonly used fish anesthetic, but its mechanism of action is not fully understood. This study employed network pharmacology, molecular docking, and molecular dynamics simulation to explore the anesthetic targets of eugenol in fish. Initially, 63 potential targets for eugenol anesthesia were identified using databases such as SwissTarget, TargetNet, GeneCards, OMIM, and TTD. The DAVID database was utilized to analyze the GO functions and KEGG pathways of these targets, revealing 384 GO enrichment terms and 43 KEGG pathways. These terms involved neuroactive ligand-receptor interaction, calcium signaling pathway, and synaptic transmission. Subsequently, AutodockTools software facilitated molecular docking with targets in the KEGG pathway for "neuroactive ligand-receptor interaction." The results showed that eugenol had a strong affinity with these proteins. Concurrently, molecular dynamics simulations were conducted on the proteins with the top four lowest binding energies (Cnr1, Oprk1, Nr3c1, and Chrm5a) in the presence of eugenol. The eugenol-protein complexes remained stable and equilibrated within the dynamic environment. The results indicated that eugenol-anesthesia might affect membrane receptors, neurotransmitters, and ion signaling. This study elucidates the anesthetic mechanism of eugenol, enriches the primary data on fish anesthesia, and offers new analytical tools for understanding the action mechanisms of fishery drugs.
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Affiliation(s)
- Xiangbing Zeng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510300, China
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China
| | - Xiaoting Zheng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510300, China
- Key Laboratory of Efficient Utilization and Processing of Marine Fishery Resources of Hainan Province, Lingshui, 572426, China
| | - Jingru Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, 221002, China
| | - Hongbiao Dong
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510300, China.
- Key Laboratory of Efficient Utilization and Processing of Marine Fishery Resources of Hainan Province, Lingshui, 572426, China.
| | - Jiasong Zhang
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510300, China.
- Key Laboratory of Efficient Utilization and Processing of Marine Fishery Resources of Hainan Province, Lingshui, 572426, China.
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Wen J, Tanaka M, Zhang Y. Inhibition of 2-AG hydrolysis alleviates posttraumatic headache attributed to mild traumatic brain injury. J Headache Pain 2024; 25:115. [PMID: 39014318 PMCID: PMC11253377 DOI: 10.1186/s10194-024-01817-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 06/20/2024] [Indexed: 07/18/2024] Open
Abstract
BACKGROUND Posttraumatic headache (PTH) is a common and debilitating symptom following repetitive mild traumatic brain injury (rmTBI), and it mainly resembles a migraine-like phenotype. While modulation of the endocannabinoid system (ECS) is effective in treating TBI and various types of pain including migraine, the role of augmentation of endocannabinoids in treating PTH has not been investigated. METHODS Repetitive mild TBI was induced in male C57BL/6J mice using the non-invasive close-head impact model of engineered rotational acceleration (CHIMERA). Periorbital allodynia was assessed using von Frey filaments and determined by the "Up-Down" method. Immunofluorescence staining was employed to investigate glial cell activation and calcitonin gene-related peptide (CGRP) expression in the trigeminal ganglion (TG) and trigeminal nucleus caudalis (TNC) of the rmTBI mice. Levels of 2-arachidonoyl glycerol (2-AG), anandamide (AEA), and arachidonic acid (AA) in the TG, medulla (including TNC), and periaqueductal gray (PAG) were measured by mass spectrometry. The therapeutic effect of endocannabinoid modulation on PTH was also assessed. RESULTS The rmTBI mice exhibited significantly increased cephalic pain hypersensitivity compared to the sham controls. MJN110, a potent and selective inhibitor of the 2-AG hydrolytic enzyme monoacylglycerol lipase (MAGL), dose-dependently attenuated periorbital allodynia in the rmTBI animals. Administration of CGRP at 0.01 mg/kg reinstated periorbital allodynia in the rmTBI animals on days 33 and 45 post-injury but had no effect in the sham and MJN110 treatment groups. Activation of glial cells along with increased production of CGRP in the TG and TNC at 7 and 14 days post-rmTBI were attenuated by MJN110 treatment. The anti-inflammatory and anti-nociceptive effects of MJN110 were partially mediated by cannabinoid receptor activation, and the pain-suppressive effect of MJN110 was completely blocked by co-administration of DO34, an inhibitor of 2-AG synthase. The levels of 2-AG in TG, TNC and PAG were decreased in TBI animals, significantly elevated and further reduced by the selective inhibitors of 2-AG hydrolytic and synthetic enzymes, respectively. CONCLUSION Enhancing endogenous levels of 2-AG appears to be an effective strategy for the treatment of PTH by attenuating pain initiation and transmission in the trigeminal pathway and facilitating descending pain inhibitory modulation.
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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
| | - 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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Pontearso M, Slepicka J, Bhattacharyya A, Spicarova D, Palecek J. Dual effect of anandamide on spinal nociceptive transmission in control and inflammatory conditions. Biomed Pharmacother 2024; 173:116369. [PMID: 38452657 DOI: 10.1016/j.biopha.2024.116369] [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: 11/23/2023] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/09/2024] Open
Abstract
Anandamide (AEA) is an important modulator of nociception in the spinal dorsal horn, acting presynaptically through Cannabinoid (CB1) and Transient receptor potential vanilloid (TRPV1) receptors. The role of AEA (1 µM, 10 µM, and 30 µM) application on the modulation of nociceptive synaptic transmission under control and inflammatory conditions was studied by recording miniature excitatory postsynaptic currents (mEPSCs) from neurons in spinal cord slices. Inhibition of the CB1 receptors by PF514273, TRPV1 by SB366791, and the fatty acid amide hydrolase (FAAH) by URB597 was used. Under naïve conditions, the AEA application did not affect the mEPSCs frequency (1.43±0.12 Hz) when all the recorded neurons were considered. The mEPSC frequency increased (180.0±39.2%) only when AEA (30 µM) was applied with PF514273 and URB597. Analysis showed that one sub-population of neurons had synaptic input inhibited (39.1% of neurons), the second excited (43.5%), whereas 8.7% showed a mixed effect and 8.7% did not respond to the AEA. With inflammation, the AEA effect was highly inhibitory (72.7%), while the excitation was negligible (9.1%), and 18.2% were not modulated. After inflammation, more neurons (45.0%) responded even to low AEA by mEPSC frequency increase with PF514273/URB597 present. AEA-induced dual (excitatory/inhibitory) effects at the 1st nociceptive synapse should be considered when developing analgesics targeting the endocannabinoid system. These findings contrast the clear inhibitory effects of the AEA precursor 20:4-NAPE application described previously and suggest that modulation of endogenous AEA production may be more favorable for analgesic treatments.
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Affiliation(s)
- Monica Pontearso
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jakub Slepicka
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Anirban Bhattacharyya
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Diana Spicarova
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jiri Palecek
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
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Karimi SA, Zahra FT, Martin LJ. IUPHAR review: Navigating the role of preclinical models in pain research. Pharmacol Res 2024; 200:107073. [PMID: 38232910 DOI: 10.1016/j.phrs.2024.107073] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/09/2024] [Accepted: 01/11/2024] [Indexed: 01/19/2024]
Abstract
Chronic pain is a complex and challenging medical condition that affects millions of people worldwide. Understanding the underlying mechanisms of chronic pain is a key goal of preclinical pain research so that more effective treatment strategies can be developed. In this review, we explore nociception, pain, and the multifaceted factors that lead to chronic pain by focusing on preclinical models. We provide a detailed look into inflammatory and neuropathic pain models and discuss the most used animal models for studying the mechanisms behind these conditions. Additionally, we emphasize the vital role of these preclinical models in developing new pain-relief drugs, focusing on biologics and the therapeutic potential of NMDA and cannabinoid receptor antagonists. We also discuss the challenges of TRPV1 modulation for pain treatment, the clinical failures of neurokinin (NK)- 1 receptor antagonists, and the partial success story of Ziconotide to provide valuable lessons for preclinical pain models. Finally, we highlight the overall success and limitations of current treatments for chronic pain while providing critical insights into the development of more effective therapies to alleviate the burden of chronic pain.
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Affiliation(s)
- Seyed Asaad Karimi
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
| | - Fatama Tuz Zahra
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Loren J Martin
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada; Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada.
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Volpedo G, Oljuskin T, Cox B, Mercado Y, Askwith C, Azodi N, Bernier M, Nakhasi HL, Gannavaram S, Satoskar AR. Leishmania mexicana promotes pain-reducing metabolomic reprogramming in cutaneous lesions. iScience 2023; 26:108502. [PMID: 38125023 PMCID: PMC10730346 DOI: 10.1016/j.isci.2023.108502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 03/30/2023] [Accepted: 11/17/2023] [Indexed: 12/23/2023] Open
Abstract
Cutaneous leishmaniasis (CL) is characterized by extensive skin lesions, which are usually painless despite being associated with extensive inflammation. The molecular mechanisms responsible for this analgesia have not been identified. Through untargeted metabolomics, we found enriched anti-nociceptive metabolic pathways in L. mexicana-infected mice. Purines were elevated in infected macrophages and at the lesion site during chronic infection. These purines have anti-inflammatory and analgesic properties by acting through adenosine receptors, inhibiting TRPV1 channels, and promoting IL-10 production. We also found arachidonic acid (AA) metabolism enriched in the ear lesions compared to the non-infected controls. AA is a metabolite of anandamide (AEA) and 2-arachidonoylglycerol (2-AG). These endocannabinoids act on cannabinoid receptors 1 and 2 and TRPV1 channels to exert anti-inflammatory and analgesic effects. Our study provides evidence of metabolic pathways upregulated during L. mexicana infection that may mediate anti-nociceptive effects experienced by CL patients and identifies macrophages as a source of these metabolites.
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Affiliation(s)
- Greta Volpedo
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Timur Oljuskin
- Animal Parasitic Disease Lab, Agricultural Research Service, USDA, Beltsville, MD, USA
| | - Blake Cox
- Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Yulian Mercado
- Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Candice Askwith
- Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA
| | - Nazli Azodi
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD, USA
| | - Matthew Bernier
- Mass Spectrometry and Proteomics Facility, The Ohio State University, Columbus, OH 43210, USA
| | - Hira L. Nakhasi
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD, USA
| | - Sreenivas Gannavaram
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD, USA
| | - Abhay R. Satoskar
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
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Spicarova D, Nerandzic V, Muzik D, Pontearso M, Bhattacharyya A, Nagy I, Palecek J. Inhibition of synaptic transmission by anandamide precursor 20:4-NAPE is mediated by TRPV1 receptors under inflammatory conditions. Front Mol Neurosci 2023; 16:1188503. [PMID: 37426071 PMCID: PMC10325575 DOI: 10.3389/fnmol.2023.1188503] [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: 03/17/2023] [Accepted: 05/24/2023] [Indexed: 07/11/2023] Open
Abstract
Transient receptor potential ion channel, vanilloid subfamily, type 1 (TRPV1) cation channel, and cannabinoid receptor 1 (CB1) are essential in the modulation of nociceptive signaling in the spinal cord dorsal horn that underlies different pathological pain states. TRPV1 and CB1 receptors share the endogenous agonist anandamide (AEA), produced from N-arachidonoylphosphatidylethanolamine (20:4-NAPE). We investigated the effect of the anandamide precursor 20:4-NAPE on synaptic activity in naive and inflammatory conditions. Patch-clamp recordings of miniature excitatory postsynaptic currents (mEPSCs) from superficial dorsal horn neurons in rat acute spinal cord slices were used. Peripheral inflammation was induced by subcutaneous injection of carrageenan. Under naive conditions, mEPSCs frequency (0.96 ± 0.11 Hz) was significantly decreased after 20 μM 20:4-NAPE application (55.3 ± 7.4%). This 20:4-NAPE-induced inhibition was blocked by anandamide-synthesizing enzyme N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD) inhibitor LEI-401. In addition, the inhibition was prevented by the CB1 receptor antagonist PF 514273 (0.2 μM) but not by the TRPV1 receptor antagonist SB 366791 (10 μM). Under inflammatory conditions, 20:4-NAPE (20 μM) also exhibited a significant inhibitory effect (74.5 ± 8.9%) on the mEPSCs frequency that was prevented by the TRPV1 receptor antagonist SB 366791 but not by PF 514273 application. Our results show that 20:4-NAPE application has a significant modulatory effect on spinal cord nociceptive signaling that is mediated by both TRPV1 and CB1 presynaptic receptors, whereas peripheral inflammation changes the underlying mechanism. The switch between TRPV1 and CB1 receptor activation by the AEA precursor 20:4-NAPE during inflammation may play an important role in nociceptive processing, hence the development of pathological pain.
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Affiliation(s)
- Diana Spicarova
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Vladimir Nerandzic
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - David Muzik
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Monica Pontearso
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Anirban Bhattacharyya
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Istvan Nagy
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Faculty of Medicine, Chelsea and Westminster Hospital, London, United Kingdom
- Department of Physiology, University of Debrecen, Debrecen, Hungary
| | - Jiri Palecek
- Laboratory of Pain Research, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
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10
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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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11
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Ramsay S, Spencer NJ, Zagorodnyuk V. Endocannabinoids, anandamide and 2-AG, regulate mechanosensitivity of mucosal afferents in the Guinea pig bladder. Eur J Pharmacol 2023; 945:175624. [PMID: 36858341 DOI: 10.1016/j.ejphar.2023.175624] [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: 12/15/2022] [Revised: 02/01/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023]
Abstract
Bladder afferents play a crucial role in urine storage and voiding, and conscious sensations from the bladder. Endocannabinoids, anandamide (AEA) and 2-arachidonolylglycerol (2-AG), are endogenous ligands of G-protein coupled cannabinoid receptors 1 and 2 (CB1 and CB2) found in the CNS and peripheral organs. They also have off-target effects on some ligand- and voltage-gated channels. The aim of this study is to determine the role of AEA and 2-AG in regulation of mechanosensitivity of probable nociceptive neurons innervating the bladder - capsaicin-sensitive mucosal afferents. The activity of these afferents was determined by ex vivo single unit extracellular recordings in the guinea pig bladder. A stable analogue of anandamide, methanandamide (mAEA) evoked initial excitatory response of mucosal afferents followed by potentiation of their responses to mechanical stimulation. In the presence of TRPV1 antagonist (AMG9810), mAEA's effect on mechanosensitivity switched from excitatory to inhibitory. The inhibitory effect of mAEA is due to activation of both CB1 and CB2 cannabinoid receptors since it was abolished by combined application of selective CB1 (NESS0327) and CB2 (SR144528) antagonists. 2-AG application evoked a brief excitation of mucosal afferents, without potentiation of their mechanosensitivity, followed by the inhibition of their responses to mechanical stimulation. CB2 receptor antagonist, SR144528 abolished the inhibitory effect of 2-AG. Our data indicated that anandamide and 2-AG have opposite effects on mechanosensitivity of mucosal capsaicin-sensitive afferents in the guinea pig bladder; mAEA potentiated while 2-AG inhibited responses of mucosal afferents to mechanical stimulation. These findings are important for understanding of the role of endocannabinoids in regulating bladder sensation and function.
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Affiliation(s)
- Stewart Ramsay
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia
| | - Nick J Spencer
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia
| | - Vladimir Zagorodnyuk
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia.
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12
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Britch SC, Craft RM. Cannabidiol and Delta-9-Tetrahydrocannabinol Interactions in Male and Female Rats With Persistent Inflammatory Pain. THE JOURNAL OF PAIN 2023; 24:98-111. [PMID: 36122809 PMCID: PMC9789172 DOI: 10.1016/j.jpain.2022.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 08/12/2022] [Accepted: 09/01/2022] [Indexed: 02/08/2023]
Abstract
Cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC), 2 of the primary constituents of cannabis, are used by some individuals to self-treat chronic pain. It is unclear whether the pain-relieving effects of CBD alone and in combination with THC are consistent across genders and among types of pain. The present study compared the effects of CBD and THC given alone and in combination in male and female rats with Complete Freund's adjuvant-induced inflammatory pain. After induction of hindpaw inflammation, vehicle, CBD (0.05-2.5 mg/kg), THC (0.05-2.0 mg/kg), or a CBD:THC combination (3:1, 1:1, or 1:3 dose ratio) was administered i.p. twice daily for 3 days. Then on day 4, mechanical allodynia, thermal hyperalgesia, weight-bearing, and locomotor activity were assessed 0.5 to 4 hours after administration of the same dose combination. Hindpaw edema and open field (anxiety-like) behaviors were measured thereafter. THC alone was anti-allodynic and anti-hyperalgesic, and decreased paw thickness, locomotion, and open field behaviors. CBD alone was anti-allodynic and anti-hyperalgesic. When combined with THC, CBD tended to decrease THC effects on pain-related behaviors and exacerbate THC-induced anxiety-like behaviors, particularly in females. These results suggest that at the doses tested, CBD-THC combinations may be less beneficial than THC alone for the treatment of chronic inflammatory pain. PERSPECTIVE: The present study compared CBD and THC effects alone and in combination in male and female rats with persistent inflammatory pain. This study could help clinicians who prescribe cannabis-based medicines for inflammatory pain conditions determine which cannabis constituents may be most beneficial.
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Affiliation(s)
- Stevie C Britch
- Center on Drug and Alcohol Research, University of Kentucky, Lexington, Kentucky; Department of Behavioral Science, University of Kentucky, Lexington, Kentucky.
| | - Rebecca M Craft
- Department of Psychology, Washington State University, Pullman, Washington
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13
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Inflammation and Nitro-oxidative Stress as Drivers of Endocannabinoid System Aberrations in Mood Disorders and Schizophrenia. Mol Neurobiol 2022; 59:3485-3503. [PMID: 35347586 DOI: 10.1007/s12035-022-02800-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 03/13/2022] [Indexed: 01/02/2023]
Abstract
The endocannabinoid system (ECS) is composed of the endocannabinoid ligands anandamide (AEA) and 2-arachidonoylgycerol (2-AG), their target cannabinoid receptors (CB1 and CB2) and the enzymes involved in their synthesis and metabolism (N-acyltransferase and fatty acid amide hydrolase (FAAH) in the case of AEA and diacylglycerol lipase (DAGL) and monoacylglycerol lipase (MAGL) in the case of 2-AG). The origins of ECS dysfunction in major neuropsychiatric disorders remain to be determined, and this paper explores the possibility that they may be associated with chronically increased nitro-oxidative stress and activated immune-inflammatory pathways, and it examines the mechanisms which might be involved. Inflammation and nitro-oxidative stress are associated with both increased CB1 expression, via increased activity of the NADPH oxidases NOX4 and NOX1, and increased CNR1 expression and DNA methylation; and CB2 upregulation via increased pro-inflammatory cytokine levels, binding of the transcription factor Nrf2 to an antioxidant response element in the CNR2 promoter region and the action of miR-139. CB1 and CB2 have antagonistic effects on redox signalling, which may result from a miRNA-enabled negative feedback loop. The effects of inflammation and oxidative stress are detailed in respect of AEA and 2-AG levels, via effects on calcium homeostasis and phospholipase A2 activity; on FAAH activity, via nitrosylation/nitration of functional cysteine and/or tyrosine residues; and on 2-AG activity via effects on MGLL expression and MAGL. Finally, based on these detailed molecular neurobiological mechanisms, it is suggested that cannabidiol and dimethyl fumarate may have therapeutic potential for major depressive disorder, bipolar disorder and schizophrenia.
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14
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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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15
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Wistrom E, Chase R, Smith PR, Campbell ZT. A compendium of validated pain genes. WIREs Mech Dis 2022; 14:e1570. [PMID: 35760453 PMCID: PMC9787016 DOI: 10.1002/wsbm.1570] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/28/2022] [Accepted: 06/06/2022] [Indexed: 12/30/2022]
Abstract
The development of novel pain therapeutics hinges on the identification and rigorous validation of potential targets. Model organisms provide a means to test the involvement of specific genes and regulatory elements in pain. Here we provide a list of genes linked to pain-associated behaviors. We capitalize on results spanning over three decades to identify a set of 242 genes. They support a remarkable diversity of functions spanning action potential propagation, immune response, GPCR signaling, enzymatic catalysis, nucleic acid regulation, and intercellular signaling. Making use of existing tissue and single-cell high-throughput RNA sequencing datasets, we examine their patterns of expression. For each gene class, we discuss archetypal members, with an emphasis on opportunities for additional experimentation. Finally, we discuss how powerful and increasingly ubiquitous forward genetic screening approaches could be used to improve our ability to identify pain genes. This article is categorized under: Neurological Diseases > Genetics/Genomics/Epigenetics Neurological Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
- Eric Wistrom
- Department of Biological SciencesUniversity of Texas at DallasRichardsonTexasUSA
| | - Rebecca Chase
- Department of Biological SciencesUniversity of Texas at DallasRichardsonTexasUSA
| | - Patrick R. Smith
- Department of Biological SciencesUniversity of Texas at DallasRichardsonTexasUSA
| | - Zachary T. Campbell
- Department of Biological SciencesUniversity of Texas at DallasRichardsonTexasUSA,Center for Advanced Pain StudiesUniversity of Texas at DallasRichardsonTexasUSA
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16
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Britch SC, Craft RM. No antinociceptive synergy between morphine and delta-9-tetrahydrocannabinol in male and female rats with persistent inflammatory pain. Behav Pharmacol 2021; 32:630-639. [PMID: 34561365 PMCID: PMC8578411 DOI: 10.1097/fbp.0000000000000657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Studies have demonstrated antinociceptive synergy between morphine and delta-9-tetrahydrocannabinol (THC) in animals, but whether such synergy occurs against all types of pain and in humans is unclear. Because a majority of chronic pain patients are women, and sex differences in morphine and THC potencies have been observed in rodents, the present study examined sex-specific effects of morphine and THC given alone and in combination, in rats with persistent inflammatory pain. On day 1, baseline mechanical and thermal response thresholds, hindpaw weight-bearing, locomotor activity, and hindpaw thickness were determined. Inflammation was then induced via hindpaw injection of complete Freund's adjuvant (CFA). Three days later, morphine (s.c.), THC (i.p) or a morphine-THC combination (1:1, 3:1 and 1:3 dose ratios) was administered, and behavioral testing was conducted at 30-240 min postinjection. Morphine alone was antiallodynic and antihyperalgesic, with no sex differences, but at some doses increased weight-bearing on the CFA-treated paw more in males than females. THC alone reduced mechanical allodynia with similar potency in both sexes, but reduced thermal hyperalgesia and locomotor activity with greater potency in females than males. All morphine-THC combinations reduced allodynia and hyperalgesia, but isobolographic analysis of mechanical allodynia data showed no significant morphine-THC synergy in either sex. Additionally, whereas morphine alone was antinociceptive at doses that did not suppress locomotion, morphine-THC combinations suppressed locomotion and did not increase weight-bearing on the inflamed paw. These results suggest that THC is unlikely to be a beneficial adjuvant when given in combination with morphine for reducing established inflammatory pain.
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Affiliation(s)
- Stevie C Britch
- Center on Drug and Alcohol Research, University of Kentucky
- Department of Behavioral Science, University of Kentucky, Lexington, Kentucky
| | - Rebecca M Craft
- Department of Psychology, Washington State University, Pullman, Washington, USA
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17
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Rostami-Mansoor S, Kalantari N, Gorgani-Firouzjaee T, Ghaffari S, Ghasemi-Kasman M. Modulation of mRNA Expression of Monoacylglycerol Lipase, Diacylglycerol Lipase and Cannabinoid Receptor-1 in Mice Experimentally Infected with T. gondii. INTERNATIONAL JOURNAL OF MOLECULAR AND CELLULAR MEDICINE 2021; 10:149-155. [PMID: 34703798 PMCID: PMC8496245 DOI: 10.22088/ijmcm.bums.10.2.149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 05/15/2021] [Indexed: 11/01/2022]
Abstract
Toxoplasma gondii, an obligate intracellular parasite, infects more than 30% of world's population. This parasite is considered to be neurotropic, and has high tropism for the central nervous system, and potentially induces cryptogenic epilepsy by no clear mechanism. The current study aimed to investigate the alteration of the main components of the endocannabinoid signaling systems in T. gondii-infected mice. For this purpose, the levels of mRNA expression of monoacylglycerol lipase (MAGL), diacylglycerol lipase (DAGL) and cannabinoid receptor-1 (CB1), were measured by quantitative real time PCR.The mRNA expression level of MAGL was increased by ~ 8-fold in the brains of the Toxoplasma-infected group in comparison with non-infected mice (P<0.0001). The mRNA expression of CB1 gene in the brain of the infected mice was ~ 2 times higher than that measured in control group (P<0.01). The mRNA expression level of DAGL remained unchanged in the infected mice. Overall a substantial increase in MAGL and CB1 expression without any changes in DAGL, in the brain of infected mice suggests that T. gondii disturbs the endocannabinoid signaling pathways, which are known as neurotransmitter modulators involved in epilepsy.
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Affiliation(s)
- Sahar Rostami-Mansoor
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Narges Kalantari
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Tahmineh Gorgani-Firouzjaee
- Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Salman Ghaffari
- Department of Mycology and Parasitology, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Maryam Ghasemi-Kasman
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
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18
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Cherkasova V, Kovalchuk O, Kovalchuk I. Cannabinoids and Endocannabinoid System Changes in Intestinal Inflammation and Colorectal Cancer. Cancers (Basel) 2021; 13:4353. [PMID: 34503163 PMCID: PMC8430689 DOI: 10.3390/cancers13174353] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 08/25/2021] [Indexed: 01/02/2023] Open
Abstract
Despite the multiple preventive measures and treatment options, colorectal cancer holds a significant place in the world's disease and mortality rates. The development of novel therapy is in critical need, and based on recent experimental data, cannabinoids could become excellent candidates. This review covered known experimental studies regarding the effects of cannabinoids on intestinal inflammation and colorectal cancer. In our opinion, because colorectal cancer is a heterogeneous disease with different genomic landscapes, the choice of cannabinoids for tumor prevention and treatment depends on the type of the disease, its etiology, driver mutations, and the expression levels of cannabinoid receptors. In this review, we describe the molecular changes of the endocannabinoid system in the pathologies of the large intestine, focusing on inflammation and cancer.
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Affiliation(s)
| | - Olga Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 7X8, Canada;
| | - Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 7X8, Canada;
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19
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Stairs J, Maguire F, Lehmann C, Cox A. Cannabinoid Therapy in Female Pelvic Medicine and Reconstructive Surgery: Current Evidence and Future Directions. CURRENT BLADDER DYSFUNCTION REPORTS 2021. [DOI: 10.1007/s11884-021-00632-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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20
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Anti-inflammatory dopamine- and serotonin-based endocannabinoid epoxides reciprocally regulate cannabinoid receptors and the TRPV1 channel. Nat Commun 2021; 12:926. [PMID: 33568652 PMCID: PMC7876028 DOI: 10.1038/s41467-021-20946-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 12/10/2020] [Indexed: 12/31/2022] Open
Abstract
The endocannabinoid system is a promising target to mitigate pain as the endocannabinoids are endogenous ligands of the pain-mediating receptors—cannabinoid receptors 1 and 2 (CB1 and CB2) and TRPV1. Herein, we report on a class of lipids formed by the epoxidation of N-arachidonoyl-dopamine (NADA) and N-arachidonoyl-serotonin (NA5HT) by epoxygenases. EpoNADA and epoNA5HT are dual-functional rheostat modulators of the endocannabinoid-TRPV1 axis. EpoNADA and epoNA5HT are stronger modulators of TRPV1 than either NADA or NA5HT, and epoNA5HT displays a significantly stronger inhibition on TRPV1-mediated responses in primary afferent neurons. Moreover, epoNA5HT is a full CB1 agonist. These epoxides reduce the pro-inflammatory biomarkers IL-6, IL-1β, TNF-α and nitrous oxide and raise anti-inflammatory IL-10 cytokine in activated microglial cells. The epoxides are spontaneously generated by activated microglia cells and their formation is potentiated in the presence of anandamide. Detailed kinetics and molecular dynamics simulation studies provide evidence for this potentiation using the epoxygenase human CYP2J2. Taken together, inflammation leads to an increase in the metabolism of NADA, NA5HT and other eCBs by epoxygenases to form the corresponding epoxides. The epoxide metabolites are bioactive lipids that are potent, multi-faceted molecules, capable of influencing the activity of CB1, CB2 and TRPV1 receptors. Endocannabinoids are ligands of cannabinoid receptors and a promising target for pain management. Here, the authors report a class of lipids formed by the epoxidation of N-arachidonoyl dopamine and N-arachidonoyl serotonin by cytochrome P450 epoxygenases, which reciprocally regulate canabinoid receptors and display anti-inflammatory activity.
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21
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Kim TE, Townsend RK, Branch CL, Romero-Sandoval EA, Hsu W. Cannabinoids in the Treatment of Back Pain. Neurosurgery 2021; 87:166-175. [PMID: 32097466 DOI: 10.1093/neuros/nyz573] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/30/2019] [Indexed: 01/17/2023] Open
Abstract
Marijuana is increasingly utilized for the treatment of multiple medical problems, including back pain, in the United States. Although there is strong preclinical evidence supporting the promise of cannabinoids in the treatment of back pain, there is a paucity of clinical data supporting their use in clinical practice. Opioids are an important medication for the treatment of acute and chronic back pain, but utilization of opioid-based regimens have likely contributed to the growing opioid epidemic. The significant risk of morbidity, mortality, and dependence secondary to opioid medications have increased the interest in nonopioid medications, including cannabinoid-based pain regimens, in treating back pain. This review will provide an overview on the pharmacology, drug delivery methods, clinical evidence, and safety considerations critical to understanding the potential role of cannabinoids in the treatment of back pain.
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Affiliation(s)
- Teddy E Kim
- Department of Neurosurgery, Wake Forest University School of Medicine, Winston Salem, North Carolina
| | - Robert K Townsend
- Department of Neurosurgery, Wake Forest University School of Medicine, Winston Salem, North Carolina
| | - Charles L Branch
- Department of Neurosurgery, Wake Forest University School of Medicine, Winston Salem, North Carolina
| | - Edgar A Romero-Sandoval
- Department of Anesthesiology, Wake Forest University School of Medicine, Winston Salem, North Carolina
| | - Wesley Hsu
- Department of Neurosurgery, Wake Forest University School of Medicine, Winston Salem, North Carolina
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22
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The Neuroimmunology of Chronic Pain: From Rodents to Humans. J Neurosci 2020; 41:855-865. [PMID: 33239404 DOI: 10.1523/jneurosci.1650-20.2020] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/29/2020] [Accepted: 10/04/2020] [Indexed: 12/11/2022] Open
Abstract
Chronic pain, encompassing conditions, such as low back pain, arthritis, persistent post-surgical pain, fibromyalgia, and neuropathic pain disorders, is highly prevalent but remains poorly treated. The vast majority of therapeutics are directed solely at neurons, despite the fact that signaling between immune cells, glia, and neurons is now recognized as indispensable for the initiation and maintenance of chronic pain. This review highlights recent advances in understanding fundamental neuroimmune signaling mechanisms and novel therapeutic targets in rodent models of chronic pain. We further discuss new technological developments to study, diagnose, and quantify neuroimmune contributions to chronic pain in patient populations.
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Haspula D, Clark MA. Cannabinoid Receptors: An Update on Cell Signaling, Pathophysiological Roles and Therapeutic Opportunities in Neurological, Cardiovascular, and Inflammatory Diseases. Int J Mol Sci 2020; 21:E7693. [PMID: 33080916 PMCID: PMC7590033 DOI: 10.3390/ijms21207693] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 12/16/2022] Open
Abstract
The identification of the human cannabinoid receptors and their roles in health and disease, has been one of the most significant biochemical and pharmacological advancements to have occurred in the past few decades. In spite of the major strides made in furthering endocannabinoid research, therapeutic exploitation of the endocannabinoid system has often been a challenging task. An impaired endocannabinoid tone often manifests as changes in expression and/or functions of type 1 and/or type 2 cannabinoid receptors. It becomes important to understand how alterations in cannabinoid receptor cellular signaling can lead to disruptions in major physiological and biological functions, as they are often associated with the pathogenesis of several neurological, cardiovascular, metabolic, and inflammatory diseases. This review focusses mostly on the pathophysiological roles of type 1 and type 2 cannabinoid receptors, and it attempts to integrate both cellular and physiological functions of the cannabinoid receptors. Apart from an updated review of pre-clinical and clinical studies, the adequacy/inadequacy of cannabinoid-based therapeutics in various pathological conditions is also highlighted. Finally, alternative strategies to modulate endocannabinoid tone, and future directions are also emphasized.
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Affiliation(s)
- Dhanush Haspula
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA;
| | - Michelle A. Clark
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL 33314, USA
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PnAn13, an antinociceptive synthetic peptide inspired in the Phoneutria nigriventer toxin PnTx4(6-1) (δ-Ctenitoxin-Pn1a). Toxicon X 2020; 7:100045. [PMID: 32875290 PMCID: PMC7452081 DOI: 10.1016/j.toxcx.2020.100045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/24/2020] [Accepted: 05/29/2020] [Indexed: 11/22/2022] Open
Abstract
Animal venoms are an almost inexhaustible source for promising molecules with biological activity and the venom of Phoneutria nigriventer spider is a good example of this. Among several other toxins obtained from this venom, PnTx4(6–1), also called δ-Ctenitoxin-Pn1a, was isolated and initially described as an insect toxin that binds to the site 3 of sodium channels in cockroach nerve cord synaptosomes (Periplaneta americana) and slows down sodium current inactivation in isolated axons of this animal. This toxin did not cause any apparent toxicity to mice when intracerebroventricularly injected (30 μg). Subsequently, it was demonstrated that PnTx4(6–1) has an antinociceptive effect in three different pain models: inflammatory, induced by carrageenan; nociceptive, induced by prostaglandin E2 and neuropathic, induced by sciatic nerve constriction. Using diverse antagonists from receptors, it was shown that the cannabinoid system, via the CB1 receptor, and the opioid system, through the μ and δ receptors, are both involved in the antinociceptive effect of PnTx4(6–1). In the present work, it was synthesized a peptide, named PnAn13, based on the amino acid sequence of PnTx4(6–1) in order to try to reproduce or increase the analgesic effect of the toxin. As it was seen for the toxin, PnAn13 had antinociceptive activity, when intrathecally injected, and this effect involved the cannabinoid and opioid systems. In addition, when it was evaluated the peripheral effect of PnAn13, via intraplantar administration, this peptide was able to reverse the hyperalgesic threshold, evoked by prostaglandin E2. Therefore, using different pharmacological tools, it was shown the participation of cannabinoid and opioid systems in this effect. A synthetic peptide PnAn13, reproduced the antinociceptive effects of the PnTx4(6-1) (δ-Ctenitoxin-Pn1a) toxin. PnAn13 showed a clear analgesic effect in the nociceptive in vivo rat pain model, both centrally and peripherally. The antinociceptive effect of PnAn13 involves cannabinoid and opioid systems.
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25
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Browe BM, Olsen AR, Ramirez C, Rickman RH, Smith ESJ, Park TJ. The naked mole-rat has a functional purinergic pain pathway despite having a non-functional peptidergic pain pathway. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2020; 8:100047. [PMID: 32478202 PMCID: PMC7248424 DOI: 10.1016/j.ynpai.2020.100047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/29/2020] [Accepted: 05/01/2020] [Indexed: 01/08/2023]
Abstract
Naked mole-rats (Heterocephalus glaber) have adaptations within their pain pathway that are beneficial to survival in large colonies within poorly ventilated burrow systems, with lower O2 and higher CO2 ambient levels than ground-level environments. These adaptations ultimately lead to a partial disruption of the C-fiber pain pathway, which enables naked mole-rats to not feel pain from the acidosis associated with CO2 accumulation. One hallmark of this disruption is that naked mole-rats do not express neuropeptides, such as Substance P and calcitonin gene-related peptide in their cutaneous C-fibers, effectively making the peptidergic pain pathway hypofunctional. One C-fiber pathway that remains unstudied in the naked mole-rat is the non-peptidergic, purinergic pathway, despite this being a key pathway for inflammatory pain. The current study aimed to establish the functionality of the purinergic pathway in naked mole-rats and the effectiveness of cannabinoids in attenuating pain through this pathway. Cannabinoids can manage chronic inflammatory pain in both humans and mouse models, and studies suggest a major downstream role for the purinergic receptor, P2X3, in this treatment. Here we used Ca2+-imaging of cultured dorsal root ganglion neurons and in vivo behavioral testing to demonstrate that the P2X3 pathway is functional in naked mole-rats. Additionally, formalin-induced inflammatory pain was reduced by the cannabinoid receptor agonist, WIN55 (inflammatory, but not acute phase) and the P2X3 receptor antagonist A-317491 (acute and inflammatory phases). This study establishes that the purinergic C-fiber pathway is present and functional in naked mole-rats and that cannabinoid-mediated analgesia occurs in this species.
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Affiliation(s)
- Brigitte M. Browe
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Abigail R. Olsen
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Cesar Ramirez
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Rebecca H. Rickman
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, UK
| | | | - Thomas J. Park
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
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26
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Mariqueo TA, Zúñiga-Hernández J. Omega-3 derivatives, specialized pro-resolving mediators: Promising therapeutic tools for the treatment of pain in chronic liver disease. Prostaglandins Leukot Essent Fatty Acids 2020; 158:102095. [PMID: 32450460 DOI: 10.1016/j.plefa.2020.102095] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/02/2020] [Accepted: 03/23/2020] [Indexed: 12/12/2022]
Abstract
The main causes of liver injury are associated with inflammation and permanent damage. They can cause chronic liver disease (CLD), which is mainly related to viral hepatitis, alcohol consumption and non-alcoholic steatohepatitis, leading to fibrosis, cirrhosis and hepatocellular carcinoma. These conditions prevent the liver from working normally and make it begin to fail, which in turn may prompt a liver transplant. CLD and cirrhosis are the eleventh cause of death worldwide. At present, there are no approved pharmacological treatments to prevent, treat or resolve liver fibrosis. The prevalence of pain in the hepatic disease is elevated with ranges between 30% and 40%. Most of the pain drugs require hepatic function; therefore, the suitable control of pain is still a clinical challenge. Specialized pro-resolving mediators (SPM): lipoxins, resolvins, protectins and maresins, are potent endogenous molecules (nM concentrations) that modulate inflammatory body responses by reducing neutrophil infiltration, macrophage activity and pain sensitization. SPM have anti-inflammatory properties, stimulate tissue resolution, repair and regeneration, and exhibit anti-nociceptive actions. Furthermore, SPM were tried on different cellular, animal models and human observational data of liver injury, improving the pathogenesis of inflammation and fibrosis. In the present work, we will describe recent evidence that suggests that SPM can be used as a therapeutic option for CLD. Additionally, we will examine the role of SPM in the control of pain in pathologies associated with liver injury.
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Affiliation(s)
- T A Mariqueo
- Centro de Investigaciones Medicas, Escuela de Medicina, Universidad de Talca, Talca, Chile
| | - J Zúñiga-Hernández
- Centro de Investigaciones Medicas, Escuela de Medicina, Universidad de Talca, Talca, Chile.
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27
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Hossain MZ, Ando H, Unno S, Kitagawa J. 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:E1423. [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] [MESH Headings] [Grants] [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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Affiliation(s)
- Mohammad Zakir Hossain
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan; (S.U.); (J.K.)
| | - Hiroshi Ando
- Department of Biology, School of Dentistry, Matsumoto Dental University, 1780 Gobara, Hirooka, Shiojiri, Nagano 399-0781, Japan;
| | - Shumpei Unno
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan; (S.U.); (J.K.)
| | - Junichi Kitagawa
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan; (S.U.); (J.K.)
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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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Peripherally restricted cannabinoid 1 receptor agonist as a novel analgesic in cancer-induced bone pain. Pain 2019; 159:1814-1823. [PMID: 29781960 DOI: 10.1097/j.pain.0000000000001278] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Many malignant cancers, including breast cancer, have a propensity to invade bones, leading to excruciating bone pain. Opioids are the primary analgesics used to alleviate this cancer-induced bone pain (CIBP) but are associated with numerous severe side effects, including enhanced bone degradation, which significantly impairs patients' quality of life. By contrast, agonists activating only peripheral CB1 receptors (CB1Rs) have been shown to effectively alleviate multiple chronic pain conditions with limited side effects, yet no studies have evaluated their role(s) in CIBP. Here, we demonstrate for the first time that a peripherally selective CB1R agonist can effectively suppress CIBP. Our studies using a syngeneic murine model of CIBP show that both acute and sustained administration of a peripherally restricted CB1R agonist, 4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3-yl]ethyl}morpholine (PrNMI), significantly alleviated spontaneous pain behaviors in the animals. This analgesic effect by PrNMI can be reversed by a systemic administration but not spinal injection of SR141716, a selective CB1R antagonist. In addition, the cancer-induced bone loss in the animals was not exacerbated by a repeated administration of PrNMI. Furthermore, catalepsy and hypothermia, the common side effects induced by cannabinoids, were measured at the supratherapeutic doses of PrNMI tested. PrNMI induced mild sedation, yet no anxiety or a decrease in limb movements was detected. Overall, our studies demonstrate that CIBP can be effectively managed by using a peripherally restricted CB1R agonist, PrNMI, without inducing dose-limiting central side effects. Thus, targeting peripheral CB1Rs could be an alternative therapeutic strategy for the treatment of CIBP.
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30
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Zhang H, He S, Hu Y, Zheng H. Antagonism of Cannabinoid Receptor 1 Attenuates the Anti-Inflammatory Effects of Electroacupuncture in a Rodent Model of Migraine. Acupunct Med 2018; 34:463-470. [DOI: 10.1136/acupmed-2016-011113] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2016] [Indexed: 12/18/2022]
Abstract
Background The anti-nociceptive effects of electroacupuncture (EA) in migraine have been documented in multiple randomised controlled trials. Neurogenic inflammation plays a key role in migraine attacks, and the anti-inflammatory effects of acupuncture have been associated with the type 1 cannabinoid (CB1) receptor. Objective To investigate whether CB1 receptors mediate the anti-inflammatory effects of EA on migraine attacks. Methods A migraine model was produced in Sprague-Dawley rats by unilateral electrical stimulation of the trigeminal ganglion (TGES). Rats received EA daily on the 5 days preceding TGES with (TGES+EA+SR141716 group) or without (TGES+EA group) intraperitoneal injections of the CB1 receptor antagonist SR141716. Another group of TGES rats (TGES+MA group) and a non-TGES sham-operated group of rats (Sham+MA group) received minimal acupuncture (MA). Calcitonin gene-related peptide (CGRP) and prostaglandin E2 (PGE2) concentrations were determined in serum obtained from the ipsilateral jugular vein at initiation of TGES and 5 min after. Postmortem interleukin (IL)-1β and cyclooxygenase (COX)2 protein levels in the trigeminal ganglion (TG) and plasma protein extravasation (PPE) in the dura mater were assessed. Results TGES induced increases in serum CGRP and PGE2 levels (TGES+MA vs baseline and vs Sham: all p<0.001), as well as IL-1β and COX2 protein expression in the TG, and neurogenic PPE levels (TGES+MA vs Sham+MA: all p<0.001). EA attenuated TGES-induced increases in the levels of these proteins (TGES+EA vs TGES+MA: all p<0.001). CB1 receptor antagonism reversed the effects of EA (TGES+EA+SR141716 vs TGES+EA: all p<0.05). Conclusions CB1 receptors appear to mediate anti-inflammatory effects of EA in a rat model of migraine.
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Affiliation(s)
- Hui Zhang
- Department of Acupuncture and Moxibustion, School of Traditional Chinese Medicine Combined with Western Medicine, Southwest Medical University, Luzhou, Sichuan, China
| | - Shengdong He
- Department of Respirology, The affiliated Hospital, Southwest Medical University, Luzhou, Sichuan, China
| | - Youping Hu
- Acupuncture College, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Hui Zheng
- Acupuncture College, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
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31
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Greene NZ, Wiley JL, Yu Z, Clowers BH, Craft RM. Cannabidiol modulation of antinociceptive tolerance to Δ 9-tetrahydrocannabinol. Psychopharmacology (Berl) 2018; 235:3289-3302. [PMID: 30238130 PMCID: PMC6454895 DOI: 10.1007/s00213-018-5036-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 09/07/2018] [Indexed: 01/02/2023]
Abstract
RATIONALE Humans typically self-administer cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) together repeatedly (as in cannabis, cannabis extract, or Sativex®) to relieve pain. It has been suggested that one benefit of the drug combination may be decreased tolerance development. OBJECTIVE The present study compared the development of tolerance to the antinociceptive effects of THC given alone versus combined with CBD, in rats. METHODS THC dose-effect curves on tail withdrawal and paw pressure tests were obtained before and after twice-daily treatment with vehicle or CBD (10 mg/kg), plus vehicle or THC (3.6 mg/kg females; 9.3 mg/kg males) for 4 days. RESULTS On the first day, THC was more potent in females than males on both nociceptive tests. From pre- to post-chronic (day 1 to day 6), THC potency on the tail withdrawal test decreased more in females than males, and rats that had been treated with CBD + THC repeatedly showed greater rightward/downward shifts of the THC dose-effect curve than rats that had been treated with THC alone. Analysis of blood samples taken after day 6 testing showed that serum THC levels were higher in CBD + THC-treated females than in vehicle + THC-treated females, and THC's active metabolite 11-OH-THC and its inactive metabolite THC-COOH were lower in CBD + THC-treated rats than in vehicle + THC-treated rats of both sexes. CBD also increased serum levels of the active metabolite cannabinol in both sexes. CONCLUSION The decrease in THC's antinociceptive effects after repeated CBD exposure may be due to CBD-induced inhibition of THC metabolism, and/or antagonism of THC effects that emerges with repeated CBD treatment.
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Affiliation(s)
| | | | - Zhihao Yu
- Department of Chemistry, Washington State University, Pullman, WA
| | - Brian H. Clowers
- Department of Chemistry, Washington State University, Pullman, WA
| | - Rebecca M. Craft
- Department of Psychology, Washington State University, Pullman, WA
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32
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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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33
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Tan R, Cao L. Cannabinoid WIN-55,212-2 mesylate inhibits tumor necrosis factor-α-induced expression of nitric oxide synthase in dorsal root ganglion neurons. Int J Mol Med 2018; 42:919-925. [PMID: 29786105 PMCID: PMC6034934 DOI: 10.3892/ijmm.2018.3687] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 01/19/2018] [Indexed: 12/17/2022] Open
Abstract
Tumor necrosis factor-α (TNF-α) is an established pain modulator in the peripheral nervous system. Elevated levels of TNF-α in dorsal root ganglion (DRG) neurons reportedly is critical for neuropathic pain processing. It has been shown that the production of nitric oxide, a key player in the development and maintenance of nociception, depends on the expression of nitric oxide synthases (NOSs) and their activities. Accumulating evidence also supports an important role of cannabinoids in modulating neuropathic pain. In this study, we explored the effects and the underlying mechanisms of crosstalk between TNF-α and cannabinoid on the expression/activity of NOS in DRG neurons. With or without knockdown of p38 mitogen-activated protein kinase (MAPK), DRG neurons were treated with TNF-α in the presence or absence of synthetic cannabinoid WIN-55,212-2 mesylate (WIN-55) and selective cannabinoid receptor (CB) antagonists. TNF-α significantly increased the NOS activity as well as the mRNA stability and expression of neuronal NOS (nNOS) in DRG neurons; this was abolished by inhibiting p38 MAPK signaling. WIN-55 inhibited TNF-α-induced p38 MAPK activity as well as TNF-α-induced increase of mRNA stability and expression/activity of nNOS; the inhibitory effect of WIN-55 was blocked by a selective CB2 antagonist. Our findings suggest that TNF-α induces the expression/activity of nNOS in DRG neurons by increasing its mRNA stability by a p38 MAPK-dependent mechanism; WIN-55 inhibits this effect of TNF-α by inhibiting p38 MAPK via CB2. By linking the functions of TNF-α, NOS and cannabinoid in DRG neurons, this study adds new insights into the molecular mechanisms underlying the pharmacologic effects of cannabinoids on neuropathic pain as well as into the pathophysiology of neuropathic pain.
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Affiliation(s)
- Rong Tan
- Department of Anesthesiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Lijun Cao
- Department of Anesthesiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
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34
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Wong H, Hossain S, Cairns BE. Delta-9-tetrahydrocannabinol decreases masticatory muscle sensitization in female rats through peripheral cannabinoid receptor activation. Eur J Pain 2017; 21:1732-1742. [DOI: 10.1002/ejp.1085] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2017] [Indexed: 01/09/2023]
Affiliation(s)
- H Wong
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - S Hossain
- InMed Pharmaceuticals Inc., Vancouver, BC, Canada
| | - B E Cairns
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
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Nerandzic V, Mrozkova P, Adamek P, Spicarova D, Nagy I, Palecek J. Peripheral inflammation affects modulation of nociceptive synaptic transmission in the spinal cord induced by N-arachidonoylphosphatidylethanolamine. Br J Pharmacol 2017; 175:2322-2336. [PMID: 28476070 DOI: 10.1111/bph.13849] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/07/2017] [Accepted: 04/27/2017] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Endocannabinoids play an important role in modulating spinal nociceptive signalling, crucial for the development of pain. The cannabinoid CB1 receptor and the TRPV1 cation channel are both activated by the endocannabinoid anandamide, a product of biosynthesis from the endogenous lipid precursor N-arachidonoylphosphatidylethanolamine (20:4-NAPE). Here, we report CB1 receptor- and TRPV1-mediated effects of 20:4-NAPE on spinal synaptic transmission in control and inflammatory conditions. EXPERIMENTAL APPROACH Spontaneous (sEPSCs) and dorsal root stimulation-evoked (eEPSCs) excitatory postsynaptic currents from superficial dorsal horn neurons in rat spinal cord slices were assessed. Peripheral inflammation was induced by carrageenan. Anandamide concentration was assessed by mass spectrometry. KEY RESULTS Application of 20:4-NAPE increased anandamide concentration in vitro. 20:4-NAPE (20 μM) decreased sEPSCs frequency and eEPSCs amplitude in control and inflammatory conditions. The inhibitory effect of 20:4-NAPE was sensitive to CB1 receptor antagonist PF514273 (0.2 μM) in both conditions, but to the TRPV1 antagonist SB366791 (10 μM) only after inflammation. After inflammation, 20:4-NAPE increased sEPSCs frequency in the presence of PF514273 and this increase was blocked by SB366791. CONCLUSIONS AND IMPLICATIONS While 20:4-NAPE treatment inhibited the excitatory synaptic transmission in both naive and inflammatory conditions, peripheral inflammation altered the underlying mechanisms. Our data indicate that 20:4-NAPE application induced mainly CB1 receptor-mediated inhibitory effects in naive animals while TRPV1-mediated mechanisms were also involved after inflammation. Increasing anandamide levels for analgesic purposes by applying substrate for its local synthesis may be more effective than systemic anandamide application or inhibition of its degradation. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc.
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Affiliation(s)
- Vladimir Nerandzic
- Department of Functional Morphology, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Petra Mrozkova
- Department of Functional Morphology, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Pavel Adamek
- Department of Functional Morphology, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Diana Spicarova
- Department of Functional Morphology, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Istvan Nagy
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer Imperial College London, Faculty of Medicine, Chelsea and Westminster Hospital, London, UK
| | - Jiri Palecek
- Department of Functional Morphology, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
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Britch SC, Wiley JL, Yu Z, Clowers BH, Craft RM. Cannabidiol-Δ 9-tetrahydrocannabinol interactions on acute pain and locomotor activity. Drug Alcohol Depend 2017; 175:187-197. [PMID: 28445853 PMCID: PMC5499986 DOI: 10.1016/j.drugalcdep.2017.01.046] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 12/09/2016] [Accepted: 01/09/2017] [Indexed: 12/30/2022]
Abstract
BACKGROUND Previous studies suggest that cannabidiol (CBD) may potentiate or antagonize Δ9-tetrahydrocannabinol's (THC) effects. The current study examined sex differences in CBD modulation of THC-induced antinociception, hypolocomotion, and metabolism. METHODS In Experiment 1, CBD (0, 10 or 30mg/kg) was administered 15min before THC (0, 1.8, 3.2, 5.6 or 10mg/kg), and rats were tested for antinociception and locomotion 15-360min post-THC injection. In Experiments 2 and 3, CBD (30mg/kg) was administered 13h or 15min before THC (1.8mg/kg); rats were tested for antinociception and locomotion 30-480min post-THC injection (Experiment 2), or serum samples were taken 30-360min post-THC injection to examine CBD modulation of THC metabolism (Experiment 3). RESULTS In Experiment 1, CBD alone produced no antinociceptive effects, while enhancing THC-induced paw pressure but not tail withdrawal antinociception 4-6h post-THC injection. CBD alone increased locomotor activity at 6h post-injection, but enhanced THC-induced hypolocomotion 4-6h post-THC injection, at lower THC doses. There were no sex differences in CBD-THC interactions. In Experiments 2 and 3, CBD did not significantly enhance THC's effects when CBD was administered 13h or 15min before THC; however, CBD inhibited THC metabolism, and this effect was greater in females than males. CONCLUSIONS These results suggest that CBD may enhance THC's antinociceptive and hypolocomotive effects, primarily prolonging THC's duration of action; however, these effects were small and inconsistent across experiments. CBD inhibition of THC metabolism as well other mechanisms likely contribute to CBD-THC interactions on behavior.
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Affiliation(s)
- Stevie C. Britch
- Department of Psychology, Washington State University, Pullman, WA, USA 99164-4820
| | - Jenny L. Wiley
- RTI International, Research Triangle Park, NC, USA 27709-2194
| | - Zhihao Yu
- Department of Chemistry, Washington State University, Pullman, WA, USA, 99164-4630
| | - Brian H. Clowers
- Department of Chemistry, Washington State University, Pullman, WA, USA, 99164-4630
| | - Rebecca M. Craft
- Department of Psychology, Washington State University, Pullman, WA, USA 99164-4820
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Kumar R, Prasoon P, Gautam M, Ray SB. Comparative antinociceptive effect of arachidonylcyclopropylamide, a cannabinoid 1 receptor agonist & lignocaine, a local anaesthetic agent, following direct intrawound administration in rats. Indian J Med Res 2017; 144:730-740. [PMID: 28361827 PMCID: PMC5393085 DOI: 10.4103/ijmr.ijmr_1402_15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background & objectives: Treatment of inflammatory pain with opioids is accompanied by unpleasant and, at times, life-threatening side effects. Cannabis produces antinociception as well as psychotropic effects. It was hypothesized that peripheral cannabinoid receptors outside the central nervous system could be selectively activated for relief of pain. This study was undertaken to measure the antinociceptive effect of type 1 cannabinoid receptor (CB1r) agonist arachidonylcyclopropylamide (ACPA) in a rat model of inflammatory pain after intrawound administration and the effects were compared with lignocaine. Methods: Wounds were produced under controlled conditions by an incision in the right hind paw in rats. ACPA (10, 30 or 100 μg/10 μl) was administered directly into the wound. Antinociception was evaluated by guarding, allodynia and thermal hyperalgesia. This was compared to lignocaine (30 μg/10 μl). Reversal of ACPA (30 μg)-mediated antinociceptive effect was attempted by intrawound AM251 (100 μg), a CB1r antagonist. Antinociception was also evaluated after contralateral administration of ACPA (30 μg). Primary afferent nociceptive input to the spinal cord was investigated by c-Fos expression after ACPA treatment (100 μg). Results: ACPA, but not lignocaine, inhibited guarding behaviour, which was locally mediated. Conversely, lignocaine, but not ACPA, inhibited thermal hyperalgesia and mechanical allodynia. ACPA-mediated inhibitory effect was reversible and dose dependent. It was associated with a decreased c-Fos expression. Locomotor activity was unaffected following ACPA (100 μg) treatment. Interpretation & conclusions: Lignocaine attenuated evoked pain behaviour whereas ACPA decreased guarding score. This difference was likely due to blockade of sodium ion channels and the activation of peripheral CB1r, respectively. Central side effects were absent after ACPA treatment. Further studies need to be done to assess the effect of ACPA treatment in clinical conditions.
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Affiliation(s)
- Rahul Kumar
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India
| | - Pranav Prasoon
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India
| | - Mayank Gautam
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India
| | - Subrata Basu Ray
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India
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Sousa-Valente J, Varga A, Torres-Perez JV, Jenes A, Wahba J, Mackie K, Cravatt B, Ueda N, Tsuboi K, Santha P, Jancso G, Tailor H, Avelino A, Nagy I. Inflammation of peripheral tissues and injury to peripheral nerves induce differing effects in the expression of the calcium-sensitive N-arachydonoylethanolamine-synthesizing enzyme and related molecules in rat primary sensory neurons. J Comp Neurol 2017; 525:1778-1796. [PMID: 27997038 DOI: 10.1002/cne.24154] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 10/17/2016] [Accepted: 11/06/2016] [Indexed: 11/11/2022]
Abstract
Elevation of intracellular Ca2+ concentration induces the synthesis of N-arachydonoylethanolamine (anandamide) in a subpopulation of primary sensory neurons. N-acylphosphatidylethanolamine phospholipase D (NAPE-PLD) is the only known enzyme that synthesizes anandamide in a Ca2+ -dependent manner. NAPE-PLD mRNA as well as anandamide's main targets, the excitatory transient receptor potential vanilloid type 1 ion channel (TRPV1), the inhibitory cannabinoid type 1 (CB1) receptor, and the main anandamide-hydrolyzing enzyme fatty acid amide hydrolase (FAAH), are all expressed by subpopulations of nociceptive primary sensory neurons. Thus, NAPE-PLD, TRPV1, the CB1 receptor, and FAAH could form an autocrine signaling system that could shape the activity of a major subpopulation of nociceptive primary sensory neurons, contributing to the development of pain. Although the expression patterns of TRPV1, the CB1 receptor, and FAAH have been comprehensively elucidated, little is known about NAPE-PLD expression in primary sensory neurons under physiological and pathological conditions. This study shows that NAPE-PLD is expressed by about one-third of primary sensory neurons, the overwhelming majority of which also express nociceptive markers as well as the CB1 receptor, TRPV1, and FAAH. Inflammation of peripheral tissues and injury to peripheral nerves induce differing but concerted changes in the expression pattern of NAPE-PLD, the CB1 receptor, TRPV1, and FAAH. Together these data indicate the existence of the anatomical basis for an autocrine signaling system in a major proportion of nociceptive primary sensory neurons and that alterations in that autocrine signaling by peripheral pathologies could contribute to the development of both inflammatory and neuropathic pain.
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Affiliation(s)
- João Sousa-Valente
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom
| | - Angelika Varga
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom.,Department of Physiology, University of Debrecen, Medical and Health Science Center, Debrecen, H-4012, Hungary
| | - Jose Vicente Torres-Perez
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom
| | - Agnes Jenes
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom.,Department of Physiology, University of Debrecen, Medical and Health Science Center, Debrecen, H-4012, Hungary
| | - John Wahba
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom
| | - Ken Mackie
- Department of Psychological and Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, Indiana, 47405
| | - Benjamin Cravatt
- The Skaggs Institute for Chemical Biology and Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California, 92037
| | - Natsuo Ueda
- Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, 761-0793, Japan
| | - Kazuhito Tsuboi
- Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, 761-0793, Japan
| | - Peter Santha
- Department of Physiology, University of Szeged, 6720, Szeged, Hungary
| | - Gabor Jancso
- Department of Physiology, University of Szeged, 6720, Szeged, Hungary
| | - Hiren Tailor
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom
| | - António Avelino
- Departamento de Biologia Experimental, Faculdade de Medicina do Porto, 4200-450, Porto, Portugal.,I3S Instituto de Investigação e Inovação em Saúde, IBMC Instituto de Biologia Molecular e Celular, 4200-135, Porto, Portugal
| | - Istvan Nagy
- Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom
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Oliveira-Fusaro MCG, Zanoni CIS, Dos Santos GG, Manzo LP, Araldi D, Bonet IJM, Tambeli CH, Dias EV, Parada CA. Antihyperalgesic effect of CB 1 receptor activation involves the modulation of P2X 3 receptor in the primary afferent neuron. Eur J Pharmacol 2017; 798:113-121. [PMID: 28131783 DOI: 10.1016/j.ejphar.2017.01.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 01/18/2017] [Accepted: 01/24/2017] [Indexed: 12/18/2022]
Abstract
Cannabinoid system is a potential target for pain control. Cannabinoid receptor 1 (CB1) activation play a role in the analgesic effect of cannabinoids once it is expressed in primary afferent neurons. This study investigates whether the anti-hyperalgesic effect of CB1 receptor activation involves P2X3 receptor in primary afferent neurons. Mechanical hyperalgesia was evaluated by electronic von Frey test. Cannabinoid effect was evaluated using anandamide or ACEA, a non-selective or a selective CB1 receptor agonists, respectively; AM251, a CB1 receptor antagonist, and antisense ODN for CB1 receptor. Calcium imaging assay was performed to evaluated α,β-meATP-responsive cultured DRG neurons pretreated with ACEA. Anandamide or ACEA administered in peripheral tissue reduced the carrageenan-induced mechanical hyperalgesia. The reduction in the carrageenan-induced hyperalgesia induced by ACEA was completely reversed by administration of AM251 as well as by the intrathecal treatment with antisense ODN for CB1 receptor. Also, ACEA reduced the mechanical hyperalgesia induced by bradykinin and by α,β-meATP, a P2X3 receptor non-selective agonist, but not by tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β) and chemokine-induced chemoattractant-1 (CINC-1). Finally, CB1 receptors are co-localized with P2X3 receptors in DRG small-diameter neurons and the treatment with ACEA reduced the number of α,β-meATP-responsive cultured DRG neurons. Our data suggest that the analgesic effect of CB1 receptor activation is mediated by a negative modulation of the P2X3 receptor in the primary afferent neurons.
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MESH Headings
- Animals
- Bradykinin/pharmacology
- Carrageenan/pharmacology
- Cell Size
- Cytokines/metabolism
- Ganglia, Spinal/pathology
- Hyperalgesia/chemically induced
- Hyperalgesia/drug therapy
- Hyperalgesia/metabolism
- Hyperalgesia/pathology
- Male
- Neurons, Afferent/drug effects
- Neurons, Afferent/metabolism
- Neurons, Afferent/pathology
- Oligodeoxyribonucleotides, Antisense/genetics
- Rats
- Rats, Wistar
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptors, Purinergic P2X3/metabolism
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Affiliation(s)
| | - Cristiane Isabel Silva Zanoni
- Department of Pharmacology, Faculty of Medicine, Ribeirão Preto University of São Paulo, Ribeirão Preto, 14049-900 São Paulo, Brazil
| | - Gilson Gonçalves Dos Santos
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil
| | - Luis Paulo Manzo
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil
| | - Dionéia Araldi
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil
| | - Ivan José Magayewski Bonet
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil
| | - Cláudia Herrera Tambeli
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil
| | - Elayne Vieira Dias
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil.
| | - Carlos Amilcar Parada
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862 São Paulo, Brazil
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Activation of cannabinoid CB1 receptors suppresses the ROS-induced hypersensitivity of rat vagal lung C-fiber afferents. Pulm Pharmacol Ther 2016; 40:22-9. [DOI: 10.1016/j.pupt.2016.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 05/21/2016] [Accepted: 06/17/2016] [Indexed: 02/07/2023]
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Seltzman HH, Shiner C, Hirt EE, Gilliam AF, Thomas BF, Maitra R, Snyder R, Black SL, Patel PR, Mulpuri Y, Spigelman I. Peripherally Selective Cannabinoid 1 Receptor (CB1R) Agonists for the Treatment of Neuropathic Pain. J Med Chem 2016; 59:7525-43. [PMID: 27482723 DOI: 10.1021/acs.jmedchem.6b00516] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Alleviation of neuropathic pain by cannabinoids is limited by their central nervous system (CNS) side effects. Indole and indene compounds were engineered for high hCB1R affinity, peripheral selectivity, metabolic stability, and in vivo efficacy. An epithelial cell line assay identified candidates with <1% blood-brain barrier penetration for testing in a rat neuropathy induced by unilateral sciatic nerve entrapment (SNE). The SNE-induced mechanical allodynia was reversibly suppressed, partially or completely, after intraperitoneal or oral administration of several indenes. At doses that relieve neuropathy symptoms, the indenes completely lacked, while the brain-permeant CB1R agonist HU-210 (1) exhibited strong CNS side effects, in catalepsy, hypothermia, and motor incoordination assays. Pharmacokinetic findings of ∼0.001 cerebrospinal fluid:plasma ratio further supported limited CNS penetration. Pretreatment with selective CB1R or CB2R blockers suggested mainly CB1R contribution to an indene's antiallodynic effects. Therefore, this class of CB1R agonists holds promise as a viable treatment for neuropathic pain.
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Affiliation(s)
- Herbert H Seltzman
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Craig Shiner
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Erin E Hirt
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Anne F Gilliam
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Brian F Thomas
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Rangan Maitra
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Rod Snyder
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Sherry L Black
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Purvi R Patel
- Center for Drug Discovery, Research Triangle Institute , Research Triangle Park, North Carolina 27709, United States
| | - Yatendra Mulpuri
- Division of Oral Biology & Medicine, School of Dentistry, University of California , 10833 Le Conte Avenue, 63-078 CHS, Los Angeles, California 090095-1668, United States
| | - Igor Spigelman
- Division of Oral Biology & Medicine, School of Dentistry, University of California , 10833 Le Conte Avenue, 63-078 CHS, Los Angeles, California 090095-1668, United States
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Sharkey KA, Wiley JW. The Role of the Endocannabinoid System in the Brain-Gut Axis. Gastroenterology 2016; 151:252-66. [PMID: 27133395 PMCID: PMC4961581 DOI: 10.1053/j.gastro.2016.04.015] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 03/21/2016] [Accepted: 04/11/2016] [Indexed: 12/17/2022]
Abstract
The actions of cannabis are mediated by receptors that are part of an endogenous cannabinoid system. The endocannabinoid system (ECS) consists of the naturally occurring ligands N-arachidonoylethanolamine (anandamide) and 2-arachidonoylglycerol (2-AG), their biosynthetic and degradative enzymes, and the cannabinoid (CB) receptors CB1 and CB2. The ECS is a widely distributed transmitter system that controls gut functions peripherally and centrally. It is an important physiologic regulator of gastrointestinal motility. Polymorphisms in the gene encoding CB1 (CNR1) have been associated with some forms of irritable bowel syndrome. The ECS is involved in the control of nausea and vomiting and visceral sensation. The homeostatic role of the ECS also extends to the control of intestinal inflammation. We review the mechanisms by which the ECS links stress and visceral pain. CB1 in sensory ganglia controls visceral sensation, and transcription of CNR1 is modified through epigenetic processes under conditions of chronic stress. These processes might link stress with abdominal pain. The ECS is also involved centrally in the manifestation of stress, and endocannabinoid signaling reduces the activity of hypothalamic-pituitary-adrenal pathways via actions in specific brain regions, notably the prefrontal cortex, amygdala, and hypothalamus. Agents that modulate the ECS are in early stages of development for treatment of gastrointestinal diseases. Increasing our understanding of the ECS will greatly advance our knowledge of interactions between the brain and gut and could lead to new treatments for gastrointestinal disorders.
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Affiliation(s)
- Keith A. Sharkey
- Hotchkiss Brain Institute and Snyder Institute of Chronic Diseases, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB T2N 4N1, Canada,Corresponding author: Dr. Keith Sharkey, Department of Physiology and Pharmacology, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada, , Tel: 403-220-4601
| | - John W. Wiley
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
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Auh QS, Chun YH, Melemedjian OK, Zhang Y, Ro JY. Peripheral interactions between cannabinoid and opioid receptor agonists in a model of inflammatory mechanical hyperalgesia. Brain Res Bull 2016; 125:211-7. [PMID: 27450703 DOI: 10.1016/j.brainresbull.2016.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 01/28/2023]
Abstract
Activation of opioid and cannabinoid receptors expressed in nociceptors induces effective antihyperalgesia. In this study, we examined whether combinations of opioid and cannabinoid receptor agonists directed at the injured site would enhance therapeutic effectiveness. Behavioral pharmacology experiments were performed to compare the effects of DAMGO, a selective agonist for μ-opioid receptor (MOR), ACPA, a specific agonist for CB1, and combinations of DAMGO and ACPA in attenuating complete Freund's adjuvant (CFA)-induced mechanical hyperalgesia in the rat hindpaw. DAMGO (1μg-1mg) or ACPA (1μg-2mg) was administered into the inflamed paw when mechanical hyperalgesia was fully developed. When administered individually, DAMGO and ACPA dose-dependently reversed the mechanical hyperalgesia. DAMGO displayed a lower ED50 value (57.4±2.49μg) than ACPA (111.6±2.18μg), but ACPA produced longer lasting antihyperalgesic effects. Combinations of DAMGO and ACPA also dose-dependently attenuated mechanical hyperalgesia, but the antihyperalgesic effects were partial and transient even at high doses. Using isobolographic analysis, we determined that combined treatment with DAMGO and ACPA produced antagonistic effects with the observed ED50 of 128.4±2.28μg. Our findings showed that MOR and CB1 agonists directed at the inflamed site effectively attenuate mechanical hyperalgesia when administered individually, but exert opposing effects when administered together. The antagonistic interactions between the two classes of drugs at the inflamed site suggest distinct mechanisms unique to peripheral nociceptors or inflamed tissue, and therefore require further studies to investigate whether the therapeutic utility of the combined drug treatments in chronic pain conditions can be optimized.
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Affiliation(s)
- Q-Schick Auh
- Kyung Hee University, School of Dentistry, Department of Oral Medicine, 1 Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea
| | - Yang Hyun Chun
- Kyung Hee University, School of Dentistry, Department of Oral Medicine, 1 Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea
| | - Ohannes K Melemedjian
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St., Baltimore, MD 21201, USA
| | - Youping Zhang
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St., Baltimore, MD 21201, USA
| | - Jin Y Ro
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St., Baltimore, MD 21201, USA; Kyung Hee University, School of Dentistry, Department of Oral Medicine, 1 Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea.
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Abstract
The endocannabinoid system consists of endogenous cannabinoids (endocannabinoids), the enzymes that synthesize and degrade endocannabinoids, and the receptors that transduce the effects of endocannabinoids. Much of what we know about the function of endocannabinoids comes from studies that combine localization of endocannabinoid system components with physiological or behavioral approaches. This review will focus on the localization of the best-known components of the endocannabinoid system for which the strongest anatomical evidence exists.
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Bakali E, McDonald J, Elliott RA, Lambert DG, Tincello DG. Cannabinoid receptor expression in the bladder is altered in detrusor overactivity. Int Urogynecol J 2015. [PMID: 26224382 DOI: 10.1007/s00192-015-2802-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Immunohistochemical (IHC) evidence shows that cannabinoid receptors (CB) are expressed in human bladders and cannabinoid agonists are known to inhibit detrusor contractility. However, the mechanism for this inhibition remains unknown. In addition, the role of CB in detrusor overactivity (DO) is under-investigated. The aim of this study was to compare CB expression in normal and DO human bladders and to further characterise these receptors. METHODS Polymer chain reaction (PCR) was used to detect differences in CB transcripts in bladder samples. Differences in CB protein expression was assessed by IHC. Immunofluorescence (IF) was used to evaluate co-localisation of CB with nerve fibres. Receptor density and binding affinity were measured using the cannabinoid radioligand [(3)H]-CP-55,940. RESULTS There were higher levels of CB1 transcripts in the urothelium of patients with DO and lower levels in the detrusor, compared with normal bladders. Radioligand binding revealed CB density of 421 ± 104 fmol/mg protein in normal human bladders. IHC confirmed these findings at the protein level. IF staining demonstrated co-localisation of CB1 with choline acetyltransferase-(ChAT)-positive nerves in the detrusor and co-localisation with PGP9.5 in both urothelium and detrusor. CB2 was co-localised with both ChAT and PGP9.5 in the urothelium and the detrusor. CONCLUSIONS Cannabinoid receptor expression is reduced in the detrusor of patients with DO, which may play a role in the pathophysiology of the disease. Co-localisation of CB receptors with cholinergic nerves may suggest that CB1, being localised on pre- and postsynaptic terminals, could influence neurotransmitter release. Our findings suggest the potential role of cannabinoid agonists in overactive bladder pharmacotherapy.
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Affiliation(s)
- Evangelia Bakali
- Reproductive Sciences Section, Health Sciences, University of Leicester, Leicester, UK. .,Department of Health Sciences, Leicester Royal Infirmary, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester, LE2 7LX, UK.
| | - John McDonald
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Ruth A Elliott
- Reproductive Sciences Section, Health Sciences, University of Leicester, Leicester, UK
| | - David G Lambert
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Douglas G Tincello
- Reproductive Sciences Section, Health Sciences, University of Leicester, Leicester, UK
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Ogawa S, Kunugi H. Inhibitors of Fatty Acid Amide Hydrolase and Monoacylglycerol Lipase: New Targets for Future Antidepressants. Curr Neuropharmacol 2015; 13:760-75. [PMID: 26630956 PMCID: PMC4759315 DOI: 10.2174/1570159x13666150612225212] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 03/16/2015] [Accepted: 03/18/2015] [Indexed: 12/27/2022] Open
Abstract
Cannabis and analogs of Δ<sup>9</sup>-tetrahydrocannabinol have been used for therapeutic purposes, but their therapeutic use remains limited because of various adverse effects. Endogenous cannabinoids have been discovered, and dysregulation of endocannabinoid signaling is implicated in the pathophysiology of major depressive disorder (MDD). Recently, endocannabinoid hydrolytic enzymes such as fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) have become new therapeutic targets in the treatment of MDD. Several FAAH or MAGL inhibitors are reported to have no cannabimimetic side effects and, therefore, are new potential therapeutic options for patients with MDD who are resistant to first-line antidepressants (selective serotonin and serotonin-norepinephrine reuptake inhibitors). In this review, we focus on the possible relationships between MDD and the endocannabinoid system as well as the inhibitors' therapeutic potential. MAGL inhibitors may reduce inflammatory responses through activation of cannabinoid receptor type 2. In the hypothalamic-pituitary-adrenal axis, repeated FAAH inhibitor administration may be beneficial for reducing circulating glucocorticoid levels. Both FAAH and MAGL inhibitors may contribute to dopaminergic system regulation. Recently, several new inhibitors have been developed with strong potency and selectivity. FAAH inhibitor, MAGL inhibitor, or dual blocker use would be promising new treatments for MDD. Further pre-clinical studies and clinical trials using these inhibitors are warranted.
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Affiliation(s)
| | - Hiroshi Kunugi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.
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dos Santos GG, Dias EV, Teixeira JM, Athie MCP, Bonet IJM, Tambeli CH, Parada CA. The analgesic effect of dipyrone in peripheral tissue involves two different mechanisms: Neuronal KATP channel opening and CB1 receptor activation. Eur J Pharmacol 2014; 741:124-31. [DOI: 10.1016/j.ejphar.2014.07.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 07/10/2014] [Accepted: 07/11/2014] [Indexed: 10/25/2022]
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Activation of CB1 inhibits NGF-induced sensitization of TRPV1 in adult mouse afferent neurons. Neuroscience 2014; 277:679-89. [PMID: 25088915 DOI: 10.1016/j.neuroscience.2014.07.041] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 06/12/2014] [Accepted: 07/02/2014] [Indexed: 01/02/2023]
Abstract
Transient receptor potential vanilloid 1 (TRPV1)-containing afferent neurons convey nociceptive signals and play an essential role in pain sensation. Exposure to nerve growth factor (NGF) rapidly increases TRPV1 activity (sensitization). In the present study, we investigated whether treatment with the selective cannabinoid receptor 1 (CB1) agonist arachidonyl-2'-chloroethylamide (ACEA) affects NGF-induced sensitization of TRPV1 in adult mouse dorsal root ganglion (DRG) afferent neurons. We found that CB1, NGF receptor tyrosine kinase A (trkA), and TRPV1 are present in cultured adult mouse small- to medium-sized afferent neurons and treatment with NGF (100ng/ml) for 30 min significantly increased the number of neurons that responded to capsaicin (as indicated by increased intracellular Ca(2 +) concentration). Pretreatment with the CB1 agonist ACEA (10nM) inhibited the NGF-induced response, and this effect of ACEA was reversed by a selective CB1 antagonist. Further, pretreatment with ACEA inhibited NGF-induced phosphorylation of AKT. Blocking PI3 kinase activity also attenuated the NGF-induced increase in the number of neurons that responded to capsaicin. Our results indicate that the analgesic effect of CB1 activation may in part be due to inhibition of NGF-induced sensitization of TRPV1 and also that the effect of CB1 activation is at least partly mediated by attenuation of NGF-induced increased PI3 signaling.
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Sousa-Valente J, Varga A, Ananthan K, Khajuria A, Nagy I. Anandamide in primary sensory neurons: too much of a good thing? Eur J Neurosci 2014; 39:409-18. [DOI: 10.1111/ejn.12467] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 11/22/2013] [Accepted: 12/02/2013] [Indexed: 01/01/2023]
Affiliation(s)
- João Sousa-Valente
- Section of Anaesthetics, Pain Medicine and Intensive Care; Department of Surgery and Cancer; Imperial College London; 369 Fulham Road London SW10 9NH UK
| | - Angelika Varga
- Section of Anaesthetics, Pain Medicine and Intensive Care; Department of Surgery and Cancer; Imperial College London; 369 Fulham Road London SW10 9NH UK
| | - Kajaluxy Ananthan
- Section of Anaesthetics, Pain Medicine and Intensive Care; Department of Surgery and Cancer; Imperial College London; 369 Fulham Road London SW10 9NH UK
| | - Ankur Khajuria
- Section of Anaesthetics, Pain Medicine and Intensive Care; Department of Surgery and Cancer; Imperial College London; 369 Fulham Road London SW10 9NH UK
| | - Istvan Nagy
- Section of Anaesthetics, Pain Medicine and Intensive Care; Department of Surgery and Cancer; Imperial College London; 369 Fulham Road London SW10 9NH UK
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