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Carruthers ER, Grimsey NL. Cannabinoid CB 2 receptor orthologues; in vitro function and perspectives for preclinical to clinical translation. Br J Pharmacol 2024; 181:2247-2269. [PMID: 37349984 DOI: 10.1111/bph.16172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 05/01/2023] [Accepted: 05/22/2023] [Indexed: 06/24/2023] Open
Abstract
Cannabinoid CB2 receptor agonists are in development as therapeutic agents, including for immune modulation and pain relief. Despite promising results in rodent preclinical studies, efficacy in human clinical trials has been marginal to date. Fundamental differences in ligand engagement and signalling responses between the human CB2 receptor and preclinical model species orthologues may contribute to mismatches in functional outcomes. This is a tangible possibility for the CB2 receptor in that there is a relatively large degree of primary amino acid sequence divergence between human and rodent. Here, we summarise CB2 receptor gene and protein structure, assess comparative molecular pharmacology between CB2 receptor orthologues, and review the current status of preclinical to clinical translation for drugs targeted at the CB2 receptor, focusing on comparisons between human, mouse and rat receptors. We hope that raising wider awareness of, and proposing strategies to address, this additional challenge in drug development will assist in ongoing efforts toward successful therapeutic translation of drugs targeted at the CB2 receptor. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein-Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc.
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Affiliation(s)
- Emma R Carruthers
- Department of Pharmacology and Clinical Pharmacology, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Natasha L Grimsey
- Department of Pharmacology and Clinical Pharmacology, School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
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Endocannabinoid System: Chemical Characteristics and Biological Activity. Pharmaceuticals (Basel) 2023; 16:ph16020148. [PMID: 37017445 PMCID: PMC9966761 DOI: 10.3390/ph16020148] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/20/2023] Open
Abstract
The endocannabinoid system (eCB) has been studied to identify the molecular structures present in Cannabis sativa. eCB consists of cannabinoid receptors, endogenous ligands, and the associated enzymatic apparatus responsible for maintaining energy homeostasis and cognitive processes. Several physiological effects of cannabinoids are exerted through interactions with various receptors, such as CB1 and CB2 receptors, vanilloid receptors, and the recently discovered G-protein-coupled receptors (GPR55, GPR3, GPR6, GPR12, and GPR19). Anandamide (AEA) and 2-arachidoylglycerol (2-AG), two small lipids derived from arachidonic acid, showed high-affinity binding to both CB1 and CB2 receptors. eCB plays a critical role in chronic pain and mood disorders and has been extensively studied because of its wide therapeutic potential and because it is a promising target for the development of new drugs. Phytocannabinoids and synthetic cannabinoids have shown varied affinities for eCB and are relevant to the treatment of several neurological diseases. This review provides a description of eCB components and discusses how phytocannabinoids and other exogenous compounds may regulate the eCB balance. Furthermore, we show the hypo- or hyperfunctionality of eCB in the body and how eCB is related to chronic pain and mood disorders, even with integrative and complementary health practices (ICHP) harmonizing the eCB.
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A PLS study on the psychotropic activity for a series of cannabinoid compounds. J Mol Model 2023; 29:46. [PMID: 36656418 DOI: 10.1007/s00894-023-05443-5] [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: 12/06/2022] [Accepted: 01/03/2023] [Indexed: 01/20/2023]
Abstract
INTRODUCTION The use of the Cannabis sativa plant by man has been common for centuries due to its numerous therapeutic properties resulting from the compounds present in it, called cannabinoids. However, the use of these compounds as drugs is still limited due to the psychotropic effects caused by them. The proteins that act as receptors of cannabinoid compounds were identified and characterized, being called CB1 and CB2 receptors. There is a series of 50 cannabinoid compounds that was studied through quantum and chemometric methods in order to obtain a mathematical model that could relate the structure of these compounds to their psychotropic activity. That model proved to be effective by predicting the psychoactivity of the 50 compounds from the series and elucidating relevant characteristics that imply in psychoactivity. However, most of these 50 compounds do not have experimental data of biological activity with CB1 and CB2 receptors. OBJECTIVES This study aims to generate QSAR models in order to predict the biological activity of the 50 cannabinoid compounds and then relate the predicted biological activity values to the already known psychoactivity. METHODS Another series of cannabinoid compounds was selected to generate and validate QSAR models, aiming to predict the biological activity of the 50 cannabinoid compounds with both CB1 and CB2 receptors. RESULTS The PLS-CB1 and PLS-CB2 QSAR models were generated and validated in this work, proving to be highly predictive, and the biological activities (pK ) of the 50 cannabinoid compounds were predicted by them. It is important to highlight compounds Ic14, Ic18, and Ic19 (psychotropic inactive) which presented higher predicted pK values than the main cannabinoid compounds (Δ9-THC and Δ8-THC). Also, compound Ic21 stood out as the highest value of the predicted biological activities in the interaction with the CB2 receptor. CONCLUSION The generated PLS models and the predicted pKi values of the 50 cannabinoid compounds can provide valuable information in the drug design of new cannabinoid compounds that can interact with CB1 and CB2 receptors in a therapeutic way with no psychotropic effects.
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Basavarajappa BS, Subbanna S. Molecular Insights into Epigenetics and Cannabinoid Receptors. Biomolecules 2022; 12:1560. [PMID: 36358910 PMCID: PMC9687363 DOI: 10.3390/biom12111560] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 09/29/2022] [Accepted: 10/22/2022] [Indexed: 09/22/2023] Open
Abstract
The actions of cannabis are mediated by G protein-coupled receptors that are part of an endogenous cannabinoid system (ECS). ECS consists of the naturally occurring ligands N-arachidonylethanolamine (anandamide) and 2-arachidonoylglycerol (2-AG), their biosynthetic and degradative enzymes, and the CB1 and CB2 cannabinoid receptors. Epigenetics are heritable changes that affect gene expression without changing the DNA sequence, transducing external stimuli in stable alterations of the DNA or chromatin structure. Cannabinoid receptors are crucial candidates for exploring their functions through epigenetic approaches due to their significant roles in health and diseases. Epigenetic changes usually promote alterations in the expression of genes and proteins that can be evaluated by various transcriptomic and proteomic analyses. Despite the exponential growth of new evidence on the critical functions of cannabinoid receptors, much is still unknown regarding the contribution of various genetic and epigenetic factors that regulate cannabinoid receptor gene expression. Recent studies have identified several immediate and long-lasting epigenetic changes, such as DNA methylation, DNA-associated histone proteins, and RNA regulatory networks, in cannabinoid receptor function. Thus, they can offer solutions to many cellular, molecular, and behavioral impairments found after modulation of cannabinoid receptor activities. In this review, we discuss the significant research advances in different epigenetic factors contributing to the regulation of cannabinoid receptors and their functions under both physiological and pathological conditions. Increasing our understanding of the epigenetics of cannabinoid receptors will significantly advance our knowledge and could lead to the identification of novel therapeutic targets and innovative treatment strategies for diseases associated with altered cannabinoid receptor functions.
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Affiliation(s)
- Balapal S. Basavarajappa
- Center for Dementia Research, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
- Molecular Imaging and Neuropathology Area, New York State Psychiatric Institute, New York, NY 10032, USA
- Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Psychiatry, New York University Langone Medical Center, New York, NY 10016, USA
| | - Shivakumar Subbanna
- Center for Dementia Research, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
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Soti M, Ranjbar H, Kohlmeier KA, Shabani M. Parkinson's disease related alterations in cannabinoid transmission. Brain Res Bull 2021; 178:82-96. [PMID: 34808322 DOI: 10.1016/j.brainresbull.2021.11.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/29/2021] [Accepted: 11/15/2021] [Indexed: 02/07/2023]
Abstract
Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic (DAergic) neurons of the substantia nigra pars compacta (SNc) by neurodegeneration. Recent findings in animal models of PD propose tonic inhibition of the remaining DA neurons through GABA release from reactive glial cells. Movement dysfunctions could be ameliorated by promotion of activity in dormant DA cells. The endocannabinoid system (ECS) is extensively present in basal ganglia (BG) and is known as an indirect modulator of DAergic neurotransmission, thus drugs designed to target this system have shown promising therapeutic potential in PD patients. Interestingly, down/up-regulation of cannabinoid receptors (CBRs) varies across the different stages of PD, suggesting that some of the motor/ non-motor deficits may be related to changes in CBRs. Determination of the profile of changes of these receptors across the different stages of PD as well as their neural distribution within the BG could improve understanding of PD and identify pathways important in disease pathobiology. In this review, we focus on temporal and spatial alterations of CBRs during PD in the BG. At present, as inconclusive, but suggestive results have been obtained, future investigations should be conducted to extend preclinical studies examining CBRs changes within each stage in controlled clinical trials in order to determine the potential of targeting CBRs in management of PD.
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Affiliation(s)
- Monavareh Soti
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
| | - Hoda Ranjbar
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
| | - Kristi A Kohlmeier
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Mohammad Shabani
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran.
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Bellocchio L, Inchingolo AD, Inchingolo AM, Lorusso F, Malcangi G, Santacroce L, Scarano A, Bordea IR, Hazballa D, D’Oria MT, Isacco CG, Nucci L, Serpico R, Tartaglia GM, Giovanniello D, Contaldo M, Farronato M, Dipalma G, Inchingolo F. Cannabinoids Drugs and Oral Health-From Recreational Side-Effects to Medicinal Purposes: A Systematic Review. Int J Mol Sci 2021; 22:ijms22158329. [PMID: 34361095 PMCID: PMC8347083 DOI: 10.3390/ijms22158329] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/01/2021] [Accepted: 08/02/2021] [Indexed: 12/15/2022] Open
Abstract
Background: marijuana, the common name for cannabis sativa preparations, is one of the most consumed drug all over the world, both at therapeutical and recreational levels. With the legalization of medical uses of cannabis in many countries, and even its recreational use in most of these, the prevalence of marijuana use has markedly risen over the last decade. At the same time, there is also a higher prevalence in the health concerns related to cannabis use and abuse. Thus, it is mandatory for oral healthcare operators to know and deal with the consequences and effects of cannabis use on oral cavity health. This review will briefly summarize the components of cannabis and the endocannabinoid system, as well as the cellular and molecular mechanisms of biological cannabis action in human cells and biologic activities on tissues. We will also look into oropharyngeal tissue expression of cannabinoid receptors, together with a putative association of cannabis to several oral diseases. Therefore, this review will elaborate the basic biology and physiology of cannabinoids in human oral tissues with the aim of providing a better comprehension of the effects of its use and abuse on oral health, in order to include cannabinoid usage into dental patient health records as well as good medicinal practice. Methods: the paper selection was performed by PubMed/Medline and EMBASE electronic databases, and reported according to the PRISMA guidelines. The scientific products were included for qualitative analysis. Results: the paper search screened a total of 276 papers. After the initial screening and the eligibility assessment, a total of 32 articles were considered for the qualitative analysis. Conclusions: today, cannabis consumption has been correlated to a higher risk of gingival and periodontal disease, oral infection and cancer of the oral cavity, while the physico-chemical activity has not been completely clarified. Further investigations are necessary to evaluate a therapeutic efficacy of this class of drugs for the promising treatment of several different diseases of the salivary glands and oral diseases.
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Affiliation(s)
- Luigi Bellocchio
- INSERM, U1215 NeuroCentre Magendie, Endocannabinoids and Neuroadaptation, University of Bordeaux, 33063 Bordeaux, France
- Correspondence: (L.B.); (F.L.); (I.R.B.); Tel.: +33646298623 (L.B.); +39-32-8213-2586 (F.L.); +40-74-4919319 (I.R.B.)
| | - Alessio Danilo Inchingolo
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
| | - Angelo Michele Inchingolo
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
| | - Felice Lorusso
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, 66100 Chieti, Italy;
- Correspondence: (L.B.); (F.L.); (I.R.B.); Tel.: +33646298623 (L.B.); +39-32-8213-2586 (F.L.); +40-74-4919319 (I.R.B.)
| | - Giuseppina Malcangi
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
| | - Luigi Santacroce
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
| | - Antonio Scarano
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, 66100 Chieti, Italy;
| | - Ioana Roxana Bordea
- Department of Oral Rehabilitation, Faculty of Dentistry, Iuliu Hațieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
- Correspondence: (L.B.); (F.L.); (I.R.B.); Tel.: +33646298623 (L.B.); +39-32-8213-2586 (F.L.); +40-74-4919319 (I.R.B.)
| | - Denisa Hazballa
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
- Kongresi Elbasanit, Rruga: Aqif Pasha, 3001 Elbasan, Albania
| | - Maria Teresa D’Oria
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
- Department of Medical and Biological Sciences, University of Udine, via delle Scienze, 206, 33100 Udine, Italy
| | - Ciro Gargiulo Isacco
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
- Human Stem Cells Research Center HSC, Ho Chi Minh 70000, Vietnam
- Embryology and Regenerative Medicine and Immunology at Pham Chau Trinh, University of Medicine, Hoi An 51300, Vietnam
| | - Ludovica Nucci
- Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania Luigi Vanvitelli, via Luigi de Crecchio, 680138 Naples, Italy; (L.N.); (R.S.); (M.C.)
| | - Rosario Serpico
- Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania Luigi Vanvitelli, via Luigi de Crecchio, 680138 Naples, Italy; (L.N.); (R.S.); (M.C.)
| | - Gianluca Martino Tartaglia
- UOC Maxillo-Facial Surgery and Dentistry, Department of Biomedical, Surgical and Dental Sciences, School of Dentistry, Fondazione IRCCS Ca Granda, Ospedale Maggiore Policlinico, University of Milan, 20100 Milan, Italy; (G.M.T.); (M.F.)
| | - Delia Giovanniello
- Hospital A.O.S.G. Moscati, Contrada Amoretta, cap, 83100 Avellino, Italy;
| | - Maria Contaldo
- Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania Luigi Vanvitelli, via Luigi de Crecchio, 680138 Naples, Italy; (L.N.); (R.S.); (M.C.)
| | - Marco Farronato
- UOC Maxillo-Facial Surgery and Dentistry, Department of Biomedical, Surgical and Dental Sciences, School of Dentistry, Fondazione IRCCS Ca Granda, Ospedale Maggiore Policlinico, University of Milan, 20100 Milan, Italy; (G.M.T.); (M.F.)
| | - Gianna Dipalma
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
| | - Francesco Inchingolo
- Department of Interdisciplinary Medicine, University of Study “Aldo Moro”, Policlinico, 70124 Bari, Italy; (A.D.I.); (A.M.I.); (G.M.); (L.S.); (D.H.); (M.T.D.); (C.G.I.); (G.D.); (F.I.)
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Ho TC, Tius MA, Nikas SP, Tran NK, Tong F, Zhou H, Zvonok N, Makriyannis A. Oxa-adamantyl cannabinoids. Bioorg Med Chem Lett 2021; 38:127882. [PMID: 33636308 DOI: 10.1016/j.bmcl.2021.127882] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/01/2021] [Accepted: 02/12/2021] [Indexed: 11/18/2022]
Abstract
As a continuation of earlier work on classical cannabinoids bearing bulky side chains we report here the design, synthesis, and biological evaluation of 3'-functionalized oxa-adamantyl cannabinoids as a novel class of cannabinergic ligands. Key synthetic steps involve nucleophilic addition/transannular cyclization of aryllithium to epoxyketone in the presence of cerium chloride and stereoselective construction of the tricyclic cannabinoid nucleus. The synthesis of the oxa-adamantyl cannabinoids is convenient, and amenable to scale up allowing the preparation of these analogs in sufficient quantities for detailed in vitro evaluation. The novel oxa-adamantyl cannabinoids reported here were found to be high affinity ligands for the CB1 and CB2 cannabinoid receptors. In the cyclase assay these compounds were found to behave as potent and efficacious CB1 receptor agonists. Isothiocyanate analog AM10504 is capable of irreversibly labeling both the CB1 and CB2 receptors.
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Affiliation(s)
- Thanh C Ho
- Department of Chemistry, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822, United States
| | - Marcus A Tius
- Department of Chemistry, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822, United States.
| | - Spyros P Nikas
- Center for Drug Discovery, Department of Chemistry and Chemical Biology, and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, United States
| | - Ngan K Tran
- Center for Drug Discovery, Department of Chemistry and Chemical Biology, and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, United States
| | - Fei Tong
- Center for Drug Discovery, Department of Chemistry and Chemical Biology, and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, United States
| | - Han Zhou
- Center for Drug Discovery, Department of Chemistry and Chemical Biology, and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, United States
| | - Nikolai Zvonok
- Center for Drug Discovery, Department of Chemistry and Chemical Biology, and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, United States
| | - Alexandros Makriyannis
- Center for Drug Discovery, Department of Chemistry and Chemical Biology, and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, United States.
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Sharma DS, Paddibhatla I, Raghuwanshi S, Malleswarapu M, Sangeeth A, Kovuru N, Dahariya S, Gautam DK, Pallepati A, Gutti RK. Endocannabinoid system: Role in blood cell development, neuroimmune interactions and associated disorders. J Neuroimmunol 2021; 353:577501. [PMID: 33571815 DOI: 10.1016/j.jneuroim.2021.577501] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/03/2021] [Accepted: 01/24/2021] [Indexed: 12/19/2022]
Abstract
The endocannabinoid system (ECS) is a complex physiological network involved in creating homeostasis and maintaining human health. Studies of the last 40 years have shown that endocannabinoids (ECs), a group of bioactive lipids, together with their set of receptors, function as one of the most important physiologic systems in human body. ECs and cannabinoid receptors (CBRs) are found throughout the body: in the brain tissues, immune cells, and in the peripheral organs and tissues as well. In recent years, ECs have emerged as key modulators of affect, neurotransmitter release, immune function, and several other physiological functions. This modulatory homoeostatic system operates in the regulation of brain activity and states of physical health and disease. In several research studies and patents the ECS has been recognised with neuro-protective properties thus it might be a target in neurodegenerative diseases. Most immune cells express these bioactive lipids and their receptors, recent data also highlight the immunomodulatory effects of endocannabinoids. Interplay of immune and nervous system has been recognized in past, recent studies suggest that ECS function as a bridge between neuronal and immune system. In several ongoing clinical trial studies, the ECS has also been placed in the anti-cancer drugs spotlight. This review summarizes the literature of cannabinoid ligands and their biosynthesis, cannabinoid receptors and their distribution, and the signaling pathways initiated by the binding of cannabinoid ligands to cannabinoid receptors. Further, this review highlights the functional role of cannabinoids and ECS in blood cell development, neuroimmune interactions and associated disorders. Moreover, we highlight the current state of knowledge of cannabinoid ligands as the mediators of neuroimmune interactions, which can be therapeutically effective for neuro-immune disorders and several diseases associated with neuroinflammation.
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Affiliation(s)
- Durga Shankar Sharma
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Indira Paddibhatla
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Sanjeev Raghuwanshi
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Mahesh Malleswarapu
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Anjali Sangeeth
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Narasaiah Kovuru
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Swati Dahariya
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Dushyant Kumar Gautam
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Aditya Pallepati
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Ravi Kumar Gutti
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India.
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Thompson KJ, Tobin AB. Crosstalk between the M 1 muscarinic acetylcholine receptor and the endocannabinoid system: A relevance for Alzheimer's disease? Cell Signal 2020; 70:109545. [PMID: 31978506 PMCID: PMC7184673 DOI: 10.1016/j.cellsig.2020.109545] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 01/19/2020] [Accepted: 01/20/2020] [Indexed: 12/16/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder which accounts for 60-70% of the 50 million worldwide cases of dementia and is characterised by cognitive impairments, many of which have long been associated with dysfunction of the cholinergic system. Although the M1 muscarinic acetylcholine receptor (mAChR) is considered a promising drug target for AD, ligands targeting this receptor have so far been unsuccessful in clinical trials. As modulatory receptors to cholinergic transmission, the endocannabinoid system may be a promising drug target to allow fine tuning of the cholinergic system. Furthermore, disease-related changes have been found in the endocannabinoid system during AD progression and indeed targeting the endocannabinoid system at specific disease stages alleviates cognitive symptoms in numerous mouse models of AD. Here we review the role of the endocannabinoid system in AD, and its crosstalk with mAChRs as a potential drug target for cholinergic dysfunction.
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Affiliation(s)
- Karen J Thompson
- Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, Davidson Building, University of Glasgow, Glasgow G12 8QQ, UK.
| | - Andrew B Tobin
- Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, Davidson Building, University of Glasgow, Glasgow G12 8QQ, UK
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10
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Tomaszewska-Zaremba D, Wojtulewicz K, Paczesna K, Tomczyk M, Biernacka K, Bochenek J, Herman AP. The Influence of Anandamide on the Anterior Pituitary Hormone Secretion in Ewes-Ex Vivo Study. Animals (Basel) 2020; 10:ani10040706. [PMID: 32316539 PMCID: PMC7222813 DOI: 10.3390/ani10040706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/25/2020] [Accepted: 04/07/2020] [Indexed: 11/16/2022] Open
Abstract
Cannabinoids (CBs) are involved in the neuroendocrine control of reproductive processes by affecting GnRH and gonadotropins secretion. The presence of cannabinoid receptors (CBR) in the pituitary raises a presumption that anandamide (AEA), the endogenous cannabinoid, may act on gonadotrophic hormones secretion directly at the level of the anterior pituitary (AP). Thus, the aim of the study was to investigate the influence of AEA on gonadotropins secretions from AP explants taken from anestrous ewes. It was demonstrated that AEA inhibited GnRH stimulated luteinizing hormone (LH) and follicle stimulating hormone (FSH) secretion from the AP explants. Anandamide influences both LH and FSH gene expressions as well as their release. AEA also affected gonadoliberin receptor (GnRHR) synthesis and expression. The presence of CB1R transcript in AP explants were also demonstrated. It could be suggested that some known negative effects of cannabinoids on the hypothalamic-pituitary-gonadal axis activity may be caused by the direct action of these compounds at the pituitary level.
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11
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Bozkurt TE. Endocannabinoid System in the Airways. Molecules 2019; 24:E4626. [PMID: 31861200 PMCID: PMC6943521 DOI: 10.3390/molecules24244626] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/12/2019] [Accepted: 12/15/2019] [Indexed: 12/12/2022] Open
Abstract
Cannabinoids and the mammalian endocannabinoid system is an important research area of interest and attracted many researchers because of their widespread biological effects. The significant immune-modulatory role of cannabinoids has suggested their therapeutic use in several inflammatory conditions. Airways are prone to environmental irritants and stimulants, and increased inflammation is an important process in most of the respiratory diseases. Therefore, the main strategies for treating airway diseases are suppression of inflammation and producing bronchodilation. The ability of cannabinoids to induce bronchodilation and modify inflammation indicates their importance for airway physiology and pathologies. In this review, the contribution of cannabinoids and the endocannabinoid system in the airways are discussed, and the existing data for their therapeutic use in airway diseases are presented.
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Affiliation(s)
- Turgut Emrah Bozkurt
- Department of Pharmacology, Faculty of Pharmacy, Hacettepe University, Ankara 06100, Turkey
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12
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Alapafuja SO, Nikas SP, Ho TC, Tong F, Benchama O, Makriyannis A. Chain Substituted Cannabilactones with Selectivity for the CB2 Cannabinoid Receptor. Molecules 2019; 24:E3559. [PMID: 31581433 PMCID: PMC6804212 DOI: 10.3390/molecules24193559] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 11/21/2022] Open
Abstract
In earlier work, we reported a novel class of CB2 selective ligands namely cannabilactones. These compounds carry a dimethylheptyl substituent at C3, which is typical for synthetic cannabinoids. In the current study with the focus on the pharmacophoric side chain at C3 we explored the effect of replacing the C1'-gem-dimethyl group with the bulkier cyclopentyl ring, and, we also probed the chain's length and terminal carbon substitution with bromo or cyano groups. One of the analogs synthesized namely 6-[1-(1,9-dihydroxy-6-oxo-6H-benzo[c]chromen-3-yl) cyclopentyl] hexanenitrile (AM4346) has very high affinity (Ki = 4.9 nM) for the mouse CB2 receptor (mCB2) and 131-fold selectivity for that target over the rat CB1 (rCB1). The species difference in the affinities of AM4346 between the mouse (m) and the human (h) CB2 receptors is reduced when compared to our first-generation cannabilactones. In the cyclase assay, our lead compound was found to be a highly potent and efficacious hCB2 receptor agonist (EC50 = 3.7 ± 1.5 nM, E(max) = 89%). We have also extended our structure-activity relationship (SAR) studies to include biphenyl synthetic intermediates that mimic the structure of the phytocannabinoid cannabinodiol.
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Affiliation(s)
- Shakiru O Alapafuja
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Spyros P Nikas
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Thanh C Ho
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Fei Tong
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Othman Benchama
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Alexandros Makriyannis
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA 02115, USA.
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13
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Cao JK, Kaplan J, Stella N. ABHD6: Its Place in Endocannabinoid Signaling and Beyond. Trends Pharmacol Sci 2019; 40:267-277. [PMID: 30853109 PMCID: PMC6445269 DOI: 10.1016/j.tips.2019.02.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/05/2019] [Accepted: 02/05/2019] [Indexed: 12/18/2022]
Abstract
The endocannabinoid (eCB) signaling system modulates neurotransmission and inflammation, among other physiological functions. Its newest member, α/β-hydrolase domain-containing 6 (ABHD6), has emerged as a promising therapeutic target to treat several devastating diseases, including epilepsy. Here, we review the molecular mechanisms that mediate and control eCB signaling and, within it, the specific role of ABHD6. We also discuss how ABHD6 controls the abundance of additional lipids and the trafficking of ionotropic receptors to plasma membranes. We finish with several unexplored questions regarding this novel enzyme. Our current understanding of the molecular mechanism and biological function of ABHD6 provides a strong foundation for the development of small-molecule therapeutics to treat devastating diseases.
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Affiliation(s)
- Jessica K Cao
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - Joshua Kaplan
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - Nephi Stella
- Department of Pharmacology, University of Washington, Seattle, WA, USA; Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
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14
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Identification of novel mouse and rat CB1R isoforms and in silico modeling of human CB1R for peripheral cannabinoid therapeutics. Acta Pharmacol Sin 2019; 40:387-397. [PMID: 30202012 DOI: 10.1038/s41401-018-0152-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 06/18/2018] [Indexed: 01/28/2023] Open
Abstract
Targeting peripheral CB1R is desirable for the treatment of metabolic syndromes without adverse neuropsychiatric effects. We previously reported a human hCB1b isoform that is selectively enriched in pancreatic beta-cells and hepatocytes, providing a potential peripheral therapeutic hCB1R target. It is unknown whether there are peripherally enriched mouse and rat CB1R (mCB1 and rCB1, respectively) isoforms. In this study, we found no evidence of peripherally enriched rodent CB1 isoforms; however, some mCB1R isoforms are absent in peripheral tissues. We show that the mouse Cnr1 gene contains six exons that are transcribed from a single promoter. We found that mCB1A is a spliced variant of extended exon 1 and protein-coding exon 6; mCB1B is a novel spliced variant containing unspliced exon 1, intron 1, and exon 2, which is then spliced to exon 6; and mCB1C is a spliced variant including all 6 exons. Using RNAscope in situ hybridization, we show that the isoforms mCB1A and mCB1B are expressed at a cellular level and colocalized in GABAergic neurons in the hippocampus and cortex. RT-qPCR reveals that mCB1A and mCB1B are enriched in the brain, while mCB1B is not expressed in the pancreas or the liver. Rat rCB1R isoforms are differentially expressed in primary cultured neurons, astrocytes, and microglia. We also investigated modulation of Cnr1 expression by insulin in vivo and carried out in silico modeling of CB1R with JD5037, a peripherally restricted CB1R inverse agonist, using the published crystal structure of hCB1R. The results provide models for future CB1R peripheral targeting.
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15
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Bukiya AN. Physiology of the Endocannabinoid System During Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1162:13-37. [PMID: 31332732 DOI: 10.1007/978-3-030-21737-2_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The endocannabinoid (eCB) system comprises endogenously produced cannabinoids (CBs), enzymes of their production and degradation, and CB-sensing receptors and transporters. The eCB system plays a critical role in virtually all stages of animal development. Studies on eCB system components and their physiological role have gained increasing attention with the rising legalization and medical use of marijuana products. The latter represent exogenous interventions that target the eCB system. This chapter summarizes knowledge in the field of CB contribution to gametogenesis, fertilization, embryo implantation, fetal development, birth, and adolescence-equivalent periods of ontogenesis. The material is complemented by the overview of data from our laboratory documenting the functional presence of the eCB system within cerebral arteries of baboons at different stages of development.
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Affiliation(s)
- Anna N Bukiya
- Department of Pharmacology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA.
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16
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Ling X, Zhang S, Liu Y, Bai M. Light-activatable cannabinoid prodrug for combined and target-specific photodynamic and cannabinoid therapy. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 30334393 DOI: 10.1117/1.jbo.23.10.108001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/19/2018] [Indexed: 06/08/2023]
Abstract
Cannabinoids are emerging as promising antitumor drugs. However, complete tumor eradication solely by cannabinoid therapy remains challenging. In this study, we developed a far-red light activatable cannabinoid prodrug, which allows for tumor-specific and combinatory cannabinoid and photodynamic therapy. This prodrug consists of a phthalocyanine photosensitizer (PS), reactive oxygen species (ROS)-sensitive linker, and cannabinoid. It targets the type-2 cannabinoid receptor (CB2R) overexpressed in various types of cancers. Upon the 690-nm light irradiation, the PS produces cytotoxic ROS, which simultaneously cleaves the ROS-sensitive linker and subsequently releases the cannabinoid drug. We found that this unique multifunctional prodrug design offered dramatically improved therapeutic efficacy, and therefore provided a new strategy for targeted, controlled, and effective antitumor cannabinoid therapy.
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Affiliation(s)
- Xiaoxi Ling
- University of Pittsburgh, Department of Radiology, Pittsburgh, Pennsylvania, United States
| | - Shaojuan Zhang
- University of Pittsburgh, Department of Radiology, Pittsburgh, Pennsylvania, United States
| | - Yang Liu
- Vanderbilt University Institute of Imaging Sciences, Nashville, Tennessee, United States
| | - Mingfeng Bai
- University of Pittsburgh, Department of Radiology, Pittsburgh, Pennsylvania, United States
- University of Pittsburgh, Department of Medicine, Pittsburgh Pennsylvania, United States
- University of Pittsburgh, Department of Bioengineering, Pittsburgh, Pennsylvania, United States
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17
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Abstract
The CB1 and CB2 cannabinoid receptors (CB1R, CB2R) are members of the G protein-coupled receptor (GPCR) family that were identified over 20 years ago. CB1Rs and CB2Rs mediate the effects of Δ9-tetrahydrocannabinol (Δ9-THC), the principal psychoactive constituent of marijuana, and subsequently identified endogenous cannabinoids (endocannabinoids) anandamide and 2-arachidonoyl glycerol. CB1Rs and CB2Rs have both similarities and differences in their pharmacology. Both receptors recognize multiple classes of agonist and antagonist compounds and produce an array of distinct downstream effects. Natural polymorphisms and alternative splice variants may also contribute to their pharmacological diversity. As our knowledge of the distinct differences grows, we may be able to target select receptor conformations and their corresponding pharmacological responses. This chapter will discuss their pharmacological characterization, distribution, phylogeny, and signaling pathways. In addition, the effects of extended agonist exposure and how that affects signaling and expression patterns of the receptors are considered.
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MESH Headings
- Alternative Splicing/genetics
- Animals
- Humans
- Phylogeny
- Polymorphism, Genetic
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
- Allyn C Howlett
- Center for Research on Substance Use and Addiction, Wake Forest University Health Sciences, Winston-Salem, NC, United States
| | - Mary E Abood
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States.
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18
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Cassano T, Calcagnini S, Pace L, De Marco F, Romano A, Gaetani S. Cannabinoid Receptor 2 Signaling in Neurodegenerative Disorders: From Pathogenesis to a Promising Therapeutic Target. Front Neurosci 2017; 11:30. [PMID: 28210207 PMCID: PMC5288380 DOI: 10.3389/fnins.2017.00030] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/16/2017] [Indexed: 12/15/2022] Open
Abstract
As a consequence of an increasingly aging population, the number of people affected by neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease and Huntington's disease, is rapidly increasing. Although the etiology of these diseases has not been completely defined, common molecular mechanisms including neuroinflammation, excitotoxicity and mitochondrial dysfunction have been confirmed and can be targeted therapeutically. Moreover, recent studies have shown that endogenous cannabinoid signaling plays a number of modulatory roles throughout the central nervous system (CNS), including the neuroinflammation and neurogenesis. In particular, the up-regulation of type-2 cannabinoid (CB2) receptors has been found in a number of neurodegenerative disorders. Thus, the modulation of CB2 receptor signaling may represent a promising therapeutic target with minimal psychotropic effects that can be used to modulate endocannabinoid-based therapeutic approaches and to reduce neuronal degeneration. For these reasons this review will focus on the CB2 receptor as a promising pharmacological target in a number of neurodegenerative diseases.
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Affiliation(s)
- Tommaso Cassano
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Silvio Calcagnini
- Department of Physiology and Pharmacology, Sapienza University of Rome Rome, Italy
| | - Lorenzo Pace
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Federico De Marco
- Laboratory of Virology, The Regina Elena National Cancer Institute IRCCS, Rome, Italy
| | - Adele Romano
- Department of Physiology and Pharmacology, Sapienza University of Rome Rome, Italy
| | - Silvana Gaetani
- Department of Physiology and Pharmacology, Sapienza University of Rome Rome, Italy
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19
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Kho DT, Glass M, Graham ES. Is the Cannabinoid CB 2 Receptor a Major Regulator of the Neuroinflammatory Axis of the Neurovascular Unit in Humans? CANNABINOID PHARMACOLOGY 2017; 80:367-396. [DOI: 10.1016/bs.apha.2017.03.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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20
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Turcotte C, Blanchet MR, Laviolette M, Flamand N. The CB 2 receptor and its role as a regulator of inflammation. Cell Mol Life Sci 2016; 73:4449-4470. [PMID: 27402121 PMCID: PMC5075023 DOI: 10.1007/s00018-016-2300-4] [Citation(s) in RCA: 344] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/20/2016] [Accepted: 06/27/2016] [Indexed: 12/12/2022]
Abstract
The CB2 receptor is the peripheral receptor for cannabinoids. It is mainly expressed in immune tissues, highlighting the possibility that the endocannabinoid system has an immunomodulatory role. In this respect, the CB2 receptor was shown to modulate immune cell functions, both in cellulo and in animal models of inflammatory diseases. In this regard, numerous studies have reported that mice lacking the CB2 receptor have an exacerbated inflammatory phenotype. This suggests that therapeutic strategies aiming at modulating CB2 signaling could be promising for the treatment of various inflammatory conditions. Herein, we review the pharmacology of the CB2 receptor, its expression pattern, and the signaling pathways induced by its activation. We next examine the regulation of immune cell functions by the CB2 receptor and the evidence obtained from primary human cells, immortalized cell lines, and animal models of inflammation. Finally, we discuss the possible therapies targeting the CB2 receptor and the questions that remain to be addressed to determine whether this receptor could be a potential target to treat inflammatory disease.
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Affiliation(s)
- Caroline Turcotte
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Département de médecine, Faculté de médecine, Université Laval, Quebec, QC, G1V 4G5, Canada
| | - Marie-Renée Blanchet
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Département de médecine, Faculté de médecine, Université Laval, Quebec, QC, G1V 4G5, Canada
| | - Michel Laviolette
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Département de médecine, Faculté de médecine, Université Laval, Quebec, QC, G1V 4G5, Canada
| | - Nicolas Flamand
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Département de médecine, Faculté de médecine, Université Laval, Quebec, QC, G1V 4G5, Canada.
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21
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Simkins TJ, Fried D, Parikh K, Galligan JJ, Goudreau JL, Lookingland KJ, Kaplan BLF. Reduced Noradrenergic Signaling in the Spleen Capsule in the Absence of CB 1 and CB 2 Cannabinoid Receptors. J Neuroimmune Pharmacol 2016; 11:669-679. [PMID: 27287619 DOI: 10.1007/s11481-016-9689-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/02/2016] [Indexed: 11/27/2022]
Abstract
The spleen is a visceral organ that contracts during hypoxia to expel erythrocytes and immune cells into the circulation. Spleen contraction is under the control of noradrenergic sympathetic innervation. The activity of noradrenergic neurons terminating in the spleen capsule is regulated by α2-adrenergic receptors (AR). Interactions between endogenous cannabinoid signaling and noradrenergic signaling in other organ systems suggest endocannabinoids might also regulate spleen contraction. Spleens from mice congenitally lacking both CB1 and CB2 cannabinoid receptors (Cnr1 -/- /Cnr2 -/- mice) were used to explore the role of endocannabinoids in spleen contraction. Spleen contraction in response to exogenous norepinephrine (NE) was found to be significantly lower in Cnr1 -/- /Cnr2 -/- mouse spleens, likely due to decreased expression of capsular α1AR. The majority of splenic Cnr1 mRNA expression is by cells of the spleen capsule, suggestive of post-synaptic CB1 receptor signaling. Thus, these studies demonstrate a role for CB1 and/or CB2 in noradrenergic splenic contraction.
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Affiliation(s)
- Tyrell J Simkins
- Neuroscience Program, Michigan State University, East Lansing, MI, USA
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
| | - David Fried
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Kevin Parikh
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - James J Galligan
- Neuroscience Program, Michigan State University, East Lansing, MI, USA
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - John L Goudreau
- Neuroscience Program, Michigan State University, East Lansing, MI, USA
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Keith J Lookingland
- Neuroscience Program, Michigan State University, East Lansing, MI, USA
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Barbara L F Kaplan
- Neuroscience Program, Michigan State University, East Lansing, MI, USA.
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA.
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA.
- Department of Basic Sciences, Mississippi State University, PO Box 6100, Mississippi State, MS, 39762, USA.
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22
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Javid FA, Phillips RM, Afshinjavid S, Verde R, Ligresti A. Cannabinoid pharmacology in cancer research: A new hope for cancer patients? Eur J Pharmacol 2016; 775:1-14. [DOI: 10.1016/j.ejphar.2016.02.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 01/05/2016] [Accepted: 02/03/2016] [Indexed: 10/22/2022]
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23
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Cannabinoid receptor 1 ligands revisited: Pharmacological assessment in the ACTOne system. Anal Biochem 2016; 498:8-28. [PMID: 26772161 DOI: 10.1016/j.ab.2015.12.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 11/22/2015] [Accepted: 12/29/2015] [Indexed: 11/23/2022]
Abstract
In vitro cannabinoid pharmacology has evolved over time from simple receptor binding to include [(35)S]GTPγ, β-arrestin, and cAMP assays. Each assay has benefits and drawbacks; however, no single functional system has been used for high-throughput evaluation of compounds from binding to pharmacological functionality and antagonist assessment in a well-characterized human cell line. In this study, we evaluated and validated one system-ACTOne human embryonic kidney cells transfected with a cyclic nucleotide gated channel and cannabinoid receptor 1 (CB1)-and compared human CB1 affinity, functional, and antagonistic effects on cAMP with previously published results. The study was conducted on a diverse group of CB1 ligands, including endocannabinoids and related compounds, 2-AG, AEA, MAEA, and ACEA, the phytocannabinoid Δ(9) THC, and synthetic cannabinoids CP 55,940, WIN 55,212-2, SR 141716A, CP 945,598, and WIN 55,212-3. Our results were compared with literature values where human CB1 was used for affinity determination and cAMP was used as a functional readout. Here we report the first detailed evaluation of the ACTOne assay for the pharmacological evaluation of CB1 ligands. The results from the study reveal some interesting deviations from previously reported functional activities of the aforementioned ligands.
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24
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Primary Macrophage Chemotaxis Induced by Cannabinoid Receptor 2 Agonists Occurs Independently of the CB2 Receptor. Sci Rep 2015; 5:10682. [PMID: 26033291 PMCID: PMC4451551 DOI: 10.1038/srep10682] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 04/13/2015] [Indexed: 12/14/2022] Open
Abstract
Activation of CB2 has been demonstrated to induce directed immune cell migration. However, the ability of CB2 to act as a chemoattractant receptor in macrophages remains largely unexplored. Using a real-time chemotaxis assay and a panel of chemically diverse and widely used CB2 agonists, we set out to examine whether CB2 modulates primary murine macrophage chemotaxis. We report that of 12 agonists tested, only JWH133, HU308, L-759,656 and L-759,633 acted as macrophage chemoattractants. Surprisingly, neither pharmacological inhibition nor genetic ablation of CB2 had any effect on CB2 agonist-induced macrophage chemotaxis. As chemotaxis was pertussis toxin sensitive in both WT and CB2-/- macrophages, we concluded that a non-CB1/CB2, Gi/o-coupled GPCR must be responsible for CB2 agonist-induced macrophage migration. The obvious candidate receptors GPR18 and GPR55 could not mediate JWH133 or HU308-induced cytoskeletal rearrangement or JWH133-induced β-arrestin recruitment in cells transfected with either receptor, demonstrating that neither are the unidentified GPCR. Taken together our results conclusively demonstrate that CB2 is not a chemoattractant receptor for murine macrophages. Furthermore we show for the first time that JWH133, HU308, L-759,656 and L-759,633 have off-target effects of functional consequence in primary cells and we believe that our findings have wide ranging implications for the entire cannabinoid field.
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25
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Harnett JJ, Dolo C, Viossat I, Auger F, Ferrandis E, Bigg D, Auguet M, Auvin S, Chabrier PE. Novel azoles as potent and selective cannabinoid CB2 receptor agonists. Bioorg Med Chem Lett 2015; 25:88-91. [DOI: 10.1016/j.bmcl.2014.11.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 10/28/2014] [Accepted: 11/01/2014] [Indexed: 01/01/2023]
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26
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Nikas SP, Sharma R, Paronis CA, Kulkarni S, Thakur GA, Hurst D, Wood JT, Gifford RS, Rajarshi G, Liu Y, Raghav JG, Guo JJ, Järbe TUC, Reggio PH, Bergman J, Makriyannis A. Probing the carboxyester side chain in controlled deactivation (-)-δ(8)-tetrahydrocannabinols. J Med Chem 2014; 58:665-81. [PMID: 25470070 PMCID: PMC4306527 DOI: 10.1021/jm501165d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
![]()
We
recently reported on a controlled deactivation/detoxification approach
for obtaining cannabinoids with improved druggability. Our design
incorporates a metabolically labile ester group at strategic positions
within the THC structure. We have now synthesized a series of (−)-Δ8-THC analogues encompassing a carboxyester group within the
3-alkyl chain in an effort to explore this novel cannabinergic chemotype
for CB receptor binding affinity, in vitro and in vivo potency and
efficacy, as well as controlled deactivation by plasma esterases.
We have also probed the chain’s polar characteristics with
regard to fast onset and short duration of action. Our lead molecule,
namely 2-[(6aR,10aR)-6a,7,10,10a-tetrahydro-1-hydroxy-6,6,9-trimethyl-6H-dibenzo[b,d]pyran-3-yl]-2-methyl-propanoic
acid 3-cyano-propyl ester (AM7438), showed picomolar affinity for
CB receptors and is deactivated by plasma esterases while the respective
acid metabolite is inactive. In further in vitro and in vivo experiments,
the compound was found to be a remarkably potent and efficacious CB1
receptor agonist with relatively fast onset/offset of action.
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Affiliation(s)
- Spyros P Nikas
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University , Boston, Massachusetts 02115, United States
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Marini P, Cascio MG, King A, Pertwee RG, Ross RA. Characterization of cannabinoid receptor ligands in tissues natively expressing cannabinoid CB2 receptors. Br J Pharmacol 2014; 169:887-99. [PMID: 23711022 DOI: 10.1111/bph.12191] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 01/06/2013] [Accepted: 02/16/2013] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND AND PURPOSE Although cannabinoid CB₂ receptor ligands have been widely characterized in recombinant systems in vitro, little pharmacological characterization has been performed in tissues natively expressing CB₂ receptors. The aim of this study was to compare the pharmacology of CB₂ receptor ligands in tissue natively expressing CB₂ receptors (human, rat and mouse spleen) and hCB₂-transfected CHO cells. EXPERIMENTAL APPROACH We tested the ability of well-known cannabinoid CB₂ receptor ligands to stimulate or inhibit [³⁵S]GTPγS binding to mouse, rat and human spleen membranes and to hCB₂-transfected CHO cell membranes. cAMP assays were also performed in hCB₂-CHO cells. KEY RESULTS The data presented demonstrate that: (i) CP 55,940, WIN 55,212-2 and JWH 133 behave as CB₂ receptor full agonists both in spleen and hCB₂-CHO cells, in both [³⁵S]GTPγS and cAMP assays; (ii) JWH 015 behaves as a low-efficacy agonist in spleen as well as in hCB₂-CHO cells when tested in the [³⁵S]GTPγS assay, while it displays full agonism when tested in the cAMP assay using hCB₂-CHO cells; (iii) (R)-AM 1241 and GW 405833 behave as agonists in the [³⁵S]GTPγS assay using spleen, instead it behaves as a low-efficacy inverse agonist in hCB₂-CHO cells; and (iv) SR 144528, AM 630 and JTE 907 behave as CB₂ receptor inverse agonists in all the tissues. CONCLUSION AND IMPLICATIONS Our results demonstrate that CB₂ receptor ligands can display differential pharmacology when assays are conducted in tissues that natively express CB₂ receptors and imply that conclusions from recombinant CB₂ receptors should be treated with caution.
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Affiliation(s)
- Pietro Marini
- School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK.
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Simkins T, Crawford RB, Goudreau JL, Lookingland KJ, Kaplan BLF. Enhanced Humoral Immunity in Mice Lacking CB1 and CB2 Receptors (Cnr1 −/− /Cnr2 −/− Mice) is not Due to Increased Splenic Noradrenergic Neuronal Activity. J Neuroimmune Pharmacol 2014; 9:544-57. [DOI: 10.1007/s11481-014-9549-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 05/12/2014] [Indexed: 01/10/2023]
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Malfitano AM, Basu S, Maresz K, Bifulco M, Dittel BN. What we know and do not know about the cannabinoid receptor 2 (CB2). Semin Immunol 2014; 26:369-79. [PMID: 24877594 DOI: 10.1016/j.smim.2014.04.002] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 04/07/2014] [Indexed: 12/19/2022]
Abstract
It has been well appreciated that the endocannabinoid system can regulate immune responses via the cannabinoid receptor 2 (CB2), which is primarily expressed by cells of the hematopoietic system. The endocannabinoid system is composed of receptors, ligands and enzymes controlling the synthesis and degradation of endocannabinoids. Along with endocannabinoids, both plant-derived and synthetic cannabinoids have been shown to bind to and signal through CB2 via G proteins leading to both inhibitory and stimulatory signals depending on the biological process. Because no cannabinoid ligand has been identified that only binds to CB2, the generation of mice deficient in CB2 has greatly expanded our knowledge of how CB2 contributes to immune cell development and function in health and disease. In regards to humans, genetic studies have associated CB2 with a variety of human diseases. Here, we review the endocannabinoid system with an emphasis on CB2 and its role in the immune system.
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Affiliation(s)
- Anna Maria Malfitano
- Dipartimento di Medicina e Chirurgia, Università di Salerno Facoltà di Medicina, Baronissi Campus, Baronissi 84081, (SA), Italy; Dipartimento di Farmacia, Università di Salerno, Fisciano 84084, (SA), Italy
| | - Sreemanti Basu
- Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA
| | - Katarzyna Maresz
- Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA
| | - Maurizio Bifulco
- Dipartimento di Medicina e Chirurgia, Università di Salerno Facoltà di Medicina, Baronissi Campus, Baronissi 84081, (SA), Italy; Dipartimento di Farmacia, Università di Salerno, Fisciano 84084, (SA), Italy
| | - Bonnie N Dittel
- Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA.
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Sharma R, Nikas SP, Guo JJ, Mallipeddi S, Wood JT, Makriyannis A. C-ring cannabinoid lactones: a novel cannabinergic chemotype. ACS Med Chem Lett 2014; 5:400-4. [PMID: 24900848 DOI: 10.1021/ml4005304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 01/14/2014] [Indexed: 02/02/2023] Open
Abstract
As a part of our controlled-deactivation ligand development project, we recently disclosed a series of (-)-Δ(8)-tetrahydrocannabinols (THCs) with a metabolically labile ester group at the 2'-position of the side chain. Now, we have replaced the C-ring in the classical THC structure with a hydrolyzable seven-membered lactone. One of the synthesized analogues binds with high affinity to the CB1 receptor (K i = 4.6 nM) and exhibits much lower affinities for the mCB2 and the hCB2. Also, in vitro functional characterization found the compound to be an agonist at rCB1. Consistent with our rational design, the lead cannabinergic lactone identified here is susceptible to metabolic inactivation by plasma esterases, while the respective acid metabolite is inactive at CB receptors. These results are highlighted with molecular modeling of the two regiosomeric lactones.
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Affiliation(s)
- Rishi Sharma
- Center for Drug Discovery
and Departments of Chemistry and Chemical Biology and Pharmaceutical
Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Spyros P. Nikas
- Center for Drug Discovery
and Departments of Chemistry and Chemical Biology and Pharmaceutical
Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Jason Jianxin Guo
- Center for Drug Discovery
and Departments of Chemistry and Chemical Biology and Pharmaceutical
Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Srikrishnan Mallipeddi
- Center for Drug Discovery
and Departments of Chemistry and Chemical Biology and Pharmaceutical
Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - JodiAnne T. Wood
- Center for Drug Discovery
and Departments of Chemistry and Chemical Biology and Pharmaceutical
Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Alexandros Makriyannis
- Center for Drug Discovery
and Departments of Chemistry and Chemical Biology and Pharmaceutical
Sciences, Northeastern University, Boston, Massachusetts 02115, United States
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Bouskila J, Javadi P, Casanova C, Ptito M, Bouchard JF. Müller cells express the cannabinoid CB2 receptor in the vervet monkey retina. J Comp Neurol 2014; 521:2399-415. [PMID: 23630038 DOI: 10.1002/cne.23333] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 03/18/2012] [Accepted: 03/13/2013] [Indexed: 12/12/2022]
Abstract
The presence of the cannabinoid receptor type 1 (CB1R) has been largely documented in the rodent and primate retinae in recent years. There is, however, some controversy concerning the presence of the CB2 receptor (CB2R) within the central nervous system. Only recently, CB2R has been found in the rodent retina, but its presence in the primate retina has not yet been demonstrated. The aim of this study was twofold: 1) to characterize the distribution patterns of CB2R in the monkey retina and compare this distribution with that previously reported for CB1R and 2) to resolve the controversy on the presence of CB2R in the neural component of the retina. We therefore thoroughly examined the cellular localization of CB2R in the vervet monkey (Chlorocebus sabeus) retina, using confocal microscopy. Our results demonstrate that CB2R, like CB1R, is present throughout the retinal layers, but with striking dissimilarities. Double labeling of CB2R and glutamine synthetase shows that CB2R is restricted to Müller cell processes, extending from the internal limiting membrane, with very low staining, to the external limiting membrane, with heavy labeling. We conclude that CB2R is indeed present in the retina but exclusively in the retinal glia, whereas CB1R is expressed only in the neuroretina. These results extend our knowledge on the expression and distribution of cannabinoid receptors in the monkey retina, although further experiments are still needed to clarify their role in retinal functions.
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Affiliation(s)
- Joseph Bouskila
- School of Optometry, University of Montreal, Montreal, Quebec, Canada H3T 1P1
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Cabral GA, Jamerson M. Marijuana use and brain immune mechanisms. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 118:199-230. [PMID: 25175866 DOI: 10.1016/b978-0-12-801284-0.00008-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The recreational smoking of marijuana, or Cannabis sativa, has become widespread, including among adolescents. Marijuana contains a class of compounds known as phytocannabinoids that include cannabidiol (CBD) and Δ(9)-tetrahydrocannabinol (THC). THC is the major psychoactive component in marijuana, but also exhibits immunosuppressive activity. CBD, while not psychotropic, also modulates immune function, but its mechanism of action appears to differ from that of THC. Since both compounds are highly lipophilic, they readily passage the blood-brain barrier and access the central nervous system. Since CBD is not psychotropic, it has been considered as a candidate therapeutic compound for ablating neuropathological processes characterized by hyperinflammation. However, an unresolved question centers around the impact of these compounds on immune-competent cells within the CNS in relation to susceptibility to infection. There are accumulating data indicating that THC inhibits the migratory capability of macrophage-like cells resident in the CNS, such as microglia, toward nodes of microbial invasion. Furthermore, phytocannabinoids have been reported to exert developmental and long-term effects on the immune system suggesting that exposure to these substances during an early stage in life has the potential to alter the fundamental neuroimmune response to select microbial agents in the adult.
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Affiliation(s)
- Guy A Cabral
- Department of Microbiology and Immunology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia, USA.
| | - Melissa Jamerson
- Department of Microbiology and Immunology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
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Sharma R, Nikas SP, Paronis CA, Wood JT, Halikhedkar A, Guo JJ, Thakur GA, Kulkarni S, Benchama O, Raghav JG, Gifford RS, Järbe TUC, Bergman J, Makriyannis A. Controlled-deactivation cannabinergic ligands. J Med Chem 2013; 56:10142-57. [PMID: 24286207 DOI: 10.1021/jm4016075] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We report an approach for obtaining novel cannabinoid analogues with controllable deactivation and improved druggability. Our design involves the incorporation of a metabolically labile ester group at the 2'-position on a series of (-)-Δ(8)-THC analogues. We have sought to introduce benzylic substituents α to the ester group which affect the half-lives of deactivation through enzymatic activity while enhancing the affinities and efficacies of individual ligands for the CB1 and CB2 receptors. The 1'-(S)-methyl, 1'-gem-dimethyl, and 1'-cyclobutyl analogues exhibit remarkably high affinities for both CB receptors. The novel ligands are susceptible to enzymatic hydrolysis by plasma esterases in a controllable manner, while their metabolites are inactive at the CB receptors. In further in vitro and in vivo experiments key analogues were shown to be potent CB1 receptor agonists and to exhibit CB1-mediated hypothermic and analgesic effects.
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Affiliation(s)
- Rishi Sharma
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University , Boston, Massachusetts 02115, United States
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Cécyre B, Thomas S, Ptito M, Casanova C, Bouchard JF. Evaluation of the specificity of antibodies raised against cannabinoid receptor type 2 in the mouse retina. Naunyn Schmiedebergs Arch Pharmacol 2013; 387:175-84. [DOI: 10.1007/s00210-013-0930-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 10/14/2013] [Indexed: 12/11/2022]
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Castaneda JT, Harui A, Kiertscher SM, Roth JD, Roth MD. Differential expression of intracellular and extracellular CB(2) cannabinoid receptor protein by human peripheral blood leukocytes. J Neuroimmune Pharmacol 2013; 8:323-32. [PMID: 23299999 PMCID: PMC3587044 DOI: 10.1007/s11481-012-9430-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 12/16/2012] [Indexed: 01/07/2023]
Abstract
mRNA encoding for the CB(2) cannabinoid receptor is expressed by many subsets of human peripheral blood leukocytes (PBL), but little is known about the resulting protein expression and function. Employing clones from the A549 and 293T cell lines that were constructed to express both full-length human CB(2) and GFP, we developed a flow cytometry assay for characterizing CB(2) protein expression. A monoclonal antibody directed against human CB(2) selectively stained the surface of transduced but not parental cell lines. When cells were fixed and permeabilized, imaging flow cytometry identified large stores of intracellular protein. Total cellular staining for CB(2) corresponded closely with the level of GFP expression. When exposed to Δ(9)-tetrahydrocannabinol, CB(2)-expressing cells internalized cell surface CB(2) receptors in a time- and dose-dependent manner. Applying these approaches to human PBL, CB(2) protein was identified on the surface of human B cells but not on T cells or monocytes. In contrast, when PBL were fixed and permeabilized, intracellular CB(2) expression was readily detected in all three subsets by both conventional and imaging flow cytometry. Similar to the protein expression pattern observed in fixed and permeabilized PBL, purified B cells, T cells, and monocytes expressed relatively equal levels of CB(2) mRNA by quantitative real-time RT-PCR. Our findings confirm that human PBL express CB(2) protein but that its distribution is predominantly intracellular with only B cells expressing CB(2) protein at the extracellular membrane. The differential role of intracellular and extracellular CB(2) receptors in mediating ligand signaling and immune function remains to be determined.
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Affiliation(s)
- Julie T Castaneda
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, CHS 37-131, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095-1690, USA
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Abstract
A safe and effective antiobesity drug is needed to combat the global obesity epidemic. The discovery of cannabinoids from medicinal herbs has revealed the endocannabinoid system (ECS) in animals and humans, which regulates various physiological activities such as feeding, thermogenesis, and body weight (BW). Although cannabinoid receptors 1 (CB1) antagonists have shown antiobesity efficacies in animal models and in the clinic, they failed to establish as a treatment due to their psychological side effects. Recent studies indicate that CB1 in various peripheral tissues may mediate some of the therapeutic effects of CB1 antagonists, such as improved lipid and glucose homeostasis. It rationalizes the development of compounds with limited brain penetration, for minimizing the side effects while retaining the therapeutic efficacies. A survey of the literature has revealed some controversies about how the ECS affects obesity. This review summarizes the research progresses and discusses some future perspectives.
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Affiliation(s)
- Guoxun Chen
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, Tennessee, USA.
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Laprairie RB, Kelly MEM, Denovan-Wright EM. The dynamic nature of type 1 cannabinoid receptor (CB(1) ) gene transcription. Br J Pharmacol 2012; 167:1583-95. [PMID: 22924606 PMCID: PMC3525862 DOI: 10.1111/j.1476-5381.2012.02175.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 07/16/2012] [Accepted: 08/03/2012] [Indexed: 01/15/2023] Open
Abstract
UNLABELLED The type 1 cannabinoid receptor (CB(1) ) is an integral component of the endocannabinoid system that modulates several functions in the CNS and periphery. The majority of our knowledge of the endocannabinoid system involves ligand-receptor binding, mechanisms of signal transduction, and protein-protein interactions. In contrast, comparatively little is known about regulation of CB(1) gene expression. The levels and anatomical distribution of CB(1) mRNA and protein are developmental stage-specific and are dysregulated in several pathological conditions. Moreover, exposure to a variety of drugs, including cannabinoids themselves, alters CB(1) gene expression and mRNA levels. As such, alterations in CB(1) gene expression are likely to affect the optimal response to cannabinoid-based therapies, which are being developed to treat a growing number of conditions. Here, we will examine the regulation of CB(1) mRNA levels and the therapeutic potential inherent in manipulating expression of this gene. LINKED ARTICLES This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.167.issue-8.
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Affiliation(s)
- R B Laprairie
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada
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Rühl T, Deuther-Conrad W, Fischer S, Günther R, Hennig L, Krautscheid H, Brust P. Cannabinoid receptor type 2 (CB2)-selective N-aryl-oxadiazolyl-propionamides: synthesis, radiolabelling, molecular modelling and biological evaluation. Org Med Chem Lett 2012; 2:32. [PMID: 23067874 PMCID: PMC3598492 DOI: 10.1186/2191-2858-2-32] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 09/21/2012] [Indexed: 12/02/2022] Open
Abstract
Background The endocannabinoid system is involved in many physiological and pathological processes. Two receptors (cannabinoid receptor type 1 (CB1) and type 2 (CB2)) are known so far. Many unwanted psychotic side effects of inhibitors of this system can be addressed to the interaction with CB1. While CB1 is one of the most abundant neuroreceptors, CB2 is expressed in the brain only at very low levels. Thus, highly potent and selective compounds for CB2 are desired. N-aryl-((hetero)aromatic)-oxadiazolyl-propionamides represent a promising class of such selective ligands for the human CB2. Here, a library of various derivatives is studied for suitable routes for labelling with 18F. Such 18F-labelled compounds can then be employed as CB2-selective radiotracers for molecular imaging studies employing positron emission tomography (PET). Results By varying the N-arylamide substructure, we explored the binding pocket of the human CB2 receptor and identified 9-ethyl-9H-carbazole amide as the group with optimal size. Radioligand replacement experiments revealed that the modification of the (hetero)aromatic moiety in 3-position of the 1,2,4-oxadiazoles shows only moderate impact on affinity to CB2 but high impact on selectivity towards CB2 with respect to CB1. Further, we could show by autoradiography studies that the most promising compounds bind selectively on CB2 receptors in mouse spleen tissue. Molecular docking studies based on a novel three-dimensional structural model of the human CB2 receptor in its activated form indicate that the compounds bind with the N-arylamide substructure in the binding pocket. 18F labelling at the (hetero)aromatic moiety at the opposite site of the compounds via radiochemistry was carried out. Conclusions The synthesized CB2-selective compounds have high affinity towards CB2 and good selectivity against CB1. The introduction of labelling groups at the (hetero)aromatic moiety shows only moderate impact on CB2 affinity, indicating the introduction of potential labelling groups at this position as a promising approach to develop CB2-selective ligands suitable for molecular imaging with PET. The high affinity for human CB2 and selectivity against human CB1 of the herein presented compounds renders them as suitable candidates for molecular imaging studies.
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Affiliation(s)
- Thomas Rühl
- Department of Neuroradiopharmaceuticals, Institute of Radiopharmacy, Research Site Leipzig, Helmholtz-Zentrum Dresden-Rossendorf e,V,, Permoserstr, 15, Leipzig, 04318, Germany.
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Console-Bram L, Marcu J, Abood ME. Cannabinoid receptors: nomenclature and pharmacological principles. Prog Neuropsychopharmacol Biol Psychiatry 2012; 38:4-15. [PMID: 22421596 PMCID: PMC3378782 DOI: 10.1016/j.pnpbp.2012.02.009] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 02/20/2012] [Accepted: 02/20/2012] [Indexed: 02/06/2023]
Abstract
The CB1 and CB2 cannabinoid receptors are members of the G protein-coupled receptor (GPCR) family that are pharmacologically well defined. However, the discovery of additional sites of action for endocannabinoids as well as synthetic cannabinoid compounds suggests the existence of additional cannabinoid receptors. Here we review this evidence, as well as the current nomenclature for classifying a target as a cannabinoid receptor. Basic pharmacological definitions, principles and experimental conditions are discussed in order to place in context the mechanisms underlying cannabinoid receptor activation. Constitutive (agonist-independent) activity is observed with the overexpression of many GPCRs, including cannabinoid receptors. Allosteric modulators can alter the pharmacological responses of cannabinoid receptors. The complex molecular architecture of each of the cannabinoid receptors allows for a single receptor to recognize multiple classes of compounds and produce an array of distinct downstream effects. Natural polymorphisms and alternative splice variants may also contribute to their pharmacological diversity. As our knowledge of the distinct differences grows, we may be able to target select receptor conformations and their corresponding pharmacological responses. Importantly, the basic biology of the endocannabinoid system will continue to be revealed by ongoing investigations.
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Affiliation(s)
- Linda Console-Bram
- Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA 19140
| | - Jahan Marcu
- Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA 19140,Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA, USA 19140
| | - Mary E. Abood
- Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA 19140,Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA, USA 19140
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The cannabinoid receptor-2 is involved in allergic inflammation. Life Sci 2012; 90:862-6. [DOI: 10.1016/j.lfs.2012.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 02/21/2012] [Accepted: 04/03/2012] [Indexed: 01/21/2023]
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Basu S, Dittel BN. Unraveling the complexities of cannabinoid receptor 2 (CB2) immune regulation in health and disease. Immunol Res 2012; 51:26-38. [PMID: 21626285 DOI: 10.1007/s12026-011-8210-5] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
It has become clear that the endocannabinoid system is a potent regulator of immune responses, with the cannabinoid receptor 2 (CB2) as the key component due to its high expression by all immune subtypes. CB2 has been shown to regulate immunity by a number of mechanisms including development, migration, proliferation, and effector functions. In addition, CB2 has been shown to modulate the function of all immune cell types examined to date. CB2 is a G(i)-protein-coupled receptor and thus exhibits a complex pharmacology allowing both stimulatory and inhibitory signaling that depends on receptor expression levels, ligand concentration, and cell lineage specificities. Here, we discuss both in vitro and in vivo experimental evidence that CB2 is a potent regulator of immune responses making it a prime target for the treatment of inflammatory diseases.
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Affiliation(s)
- Sreemanti Basu
- Blood Research Institute, Blood Center of Wisconsin, Milwaukee, WI, USA
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Onaivi ES. Commentary: Functional Neuronal CB2 Cannabinoid Receptors in the CNS. Curr Neuropharmacol 2011; 9:205-8. [PMID: 21886591 PMCID: PMC3137183 DOI: 10.2174/157015911795017416] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 04/17/2010] [Accepted: 05/26/2010] [Indexed: 11/22/2022] Open
Abstract
Cannabinoids are the constituents of the marijuana plant (Cannabis sativa). There are numerous cannabinoids and other natural compounds that have been reported in the cannabis plant. The recent progress in marijuana-cannabinoid research include the discovery of an endocannabinoid system with specific genes coding for cannabinoid receptors (CBRs) that are activated by smoking marijuana, and that the human body and brain makes its own marijuana-like substances called endocannabinoids that also activate CBRs. This new knowledge and progress about cannabinoids and endocannabinoids indicate that a balanced level of endocannabinoids is important for pregnancy and that the breast milk in animals and humans has endocannabinoids for the growth and development of the new born. There are two well characterized cannabinoid receptors termed CB1-Rs and CB2-Rs and these CBRs are perhaps the most abundant G-protein coupled receptors that are expressed at high levels in many regions of the mammalian brain. The expression of CB1-Rs in the brain and periphery and the identification of CB2-Rs in immune cells and during inflammation has been extensively studied and characterized. However, the expression of functional neuronal CB2-Rs in the CNS has been much less well established and characterized in comparison to the expression of abundant brain CB1-Rs and functional neuronal CB2-Rs has ignited debate and controversy. While the issue of the specificity of CB2-R antibodies remains, many recent studies have reported the discovery and functional characterization of functional neuronal CB2-Rs in the CNS beyond neuro-immuno cannabinoid activity.
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Affiliation(s)
- E S Onaivi
- William Paterson University, Wayne NJ and Molecular Neurobiology Branch, National Institute on Drug Abuse, NIH, Baltimore, USA
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43
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Hoyle CH. Evolution of neuronal signalling: Transmitters and receptors. Auton Neurosci 2011; 165:28-53. [DOI: 10.1016/j.autneu.2010.05.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 05/09/2010] [Accepted: 05/18/2010] [Indexed: 11/16/2022]
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Bialuk I, Winnicka MM. AM251, cannabinoids receptors ligand, improves recognition memory in rats. Pharmacol Rep 2011; 63:670-9. [DOI: 10.1016/s1734-1140(11)70578-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 01/26/2011] [Indexed: 01/15/2023]
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Fan Y, Hooker BA, Garrison TR, El-Kouhen OF, Idler KB, Holley-Shanks RR, Meyer MD, Yao BB. Pharmacological and molecular characterization of a dorsal root ganglion cell line expressing cannabinoid CB(1) and CB(2) receptors. Eur J Pharmacol 2011; 659:161-8. [PMID: 21458448 DOI: 10.1016/j.ejphar.2011.03.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 01/19/2011] [Accepted: 03/08/2011] [Indexed: 10/18/2022]
Abstract
The behavioral effects evoked by cannabinoids are primarily mediated by the CB(1) and CB(2) cannabinoid receptor subtypes. In vitro pharmacology of cannabinoid receptors has been elucidated using recombinant expression systems expressing either CB(1) or CB(2) receptors, with limited characterization in native cell lines endogenously expressing both CB(1) and CB(2) receptors. In the current study, we report the molecular and pharmacological characterization of the F-11 cell line, a hybridoma of rat dorsal root ganglion neurons and mouse neuroblastoma (N18TG2) cells, reported to endogenously express both cannabinoid receptors. The present study revealed that both receptors are of mouse origin in F-11 cells, and describes the relative gene expression levels between the two receptors. Pharmacological characterization of the F-11 cell line using cannabinoid agonists and antagonists indicated that the functional responses to these cannabinoid ligands are mainly mediated by CB(1) receptors. The non-selective cannabinoid ligands CP 55,940 and WIN 55212-2 are potent agonists and their efficacies in adenylate cyclase and MAPK assays are inhibited by the CB(1) selective antagonist SR141716A (SR1), but not by the CB(2) selective antagonist SR144528 (SR2). The endocannabinoid ligand 2AG, although not active in adenylate cyclase assays, was a potent activator of MAPK signaling in F-11 cells. The analysis of CB(1) and CB(2) receptor gene expression and the characterization of cannabinoid receptor pharmacology in the F-11 cell line demonstrate that it can be used as a tool for interrogating the endogenous signal transduction of cannabinoid receptor subtypes.
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Affiliation(s)
- Yihong Fan
- Neurological Diseases Research, Global Pharmaceutical Research & Development, Abbott Laboratories, R47W, AP9A, 100 Abbott Park Road, Abbott Park, IL 60064, USA.
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Abstract
Cannabinoids are the active chemical components of Cannabis sativa (marijuana). The medical use of cannabis goes back over 5,000 years. Cannabinoids produce a very wide array of central and peripheral effects, some of which may have beneficial clinical applications. The discovery of cannabinoid receptors has spawned great interest within the pharmaceutical industry with the hopes of capitalizing on the beneficial effects of cannabis without the unwanted psychotropic effects on the central and peripheral nervous system. This chapter presents an overview of the pharmacology of cannabinoids and their derivatives. It reviews the current literature on central and peripheral cannabinoid receptors as related to effects on the lower urinary tract and the role of these receptors in normal and abnormal urinary tract function. An objective evaluation of the published results of clinical trials of cannabis extracts for the treatment of bladder dysfunction resulting from multiple sclerosis is also presented. It is clear that cannabinoid receptors are present in the lower urinary tract as well as spinal and higher centers involved in lower urinary tract control. Systemic cannabinoids have effects on the lower urinary tract that may be able to become clinically useful; however, a much greater understanding of the mechanisms of cannabinoid receptors in control of the human lower urinary tract is necessary to facilitate development of novel cannabinoid drugs for treatment of pelvic disorders.
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Nikas SP, Alapafuja SO, Papanastasiou I, Paronis CA, Shukla VG, Papahatjis DP, Bowman AL, Halikhedkar A, Han X, Makriyannis A. Novel 1',1'-chain substituted hexahydrocannabinols: 9β-hydroxy-3-(1-hexyl-cyclobut-1-yl)-hexahydrocannabinol (AM2389) a highly potent cannabinoid receptor 1 (CB1) agonist. J Med Chem 2010; 53:6996-7010. [PMID: 20925434 DOI: 10.1021/jm100641g] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In pursuit of a more detailed understanding of the structural requirements for the key side chain cannabinoid pharmacophore, we have extended our SAR to cover a variety of conformationally modified side chains within the 9-keto and 9-hydroxyl tricyclic structures. Of the compounds described here, those with a seven-atom long side chain substituted with a cyclopentyl ring at C1' position have very high affinities for both CB1 and CB2 (0.97 nM < K(i) < 5.25 nM), with no preference for either of the two receptors. However, presence of the smaller cyclobutyl group at the C1' position leads to an optimal affinity and selectivity interaction with CB1. Thus, two of the C1'-cyclobutyl analogues, namely, (6aR,10aR)-3-(1-hexyl-cyclobut-1-yl)-6,6a,7,8,10,10a-hexahydro-1-hydroxy-6,6-dimethyl-9H-dibenzo[b,d]pyran-9-one and (6aR,9R,10aR)-3-(1-hexyl-cyclobut-1-yl)-6a,7,8,9,10,10a-hexahydro-6,6-dimethyl-6H-dibenzo[b,d]pyran-1,9 diol (7e-β, AM2389), exhibited remarkably high affinities (0.84 and 0.16 nM, respectively) and significant selectivities (16- and 26-fold, respectively) for CB1. Compound 7e-β was found to exhibit exceptionally high in vitro and in vivo potency with a relatively long duration of action.
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Affiliation(s)
- Spyros P Nikas
- Center for Drug Discovery, Northeastern University, 116 Mugar Life Sciences Building, 360 Huntington Avenue, Boston, Massachusetts 02115, USA.
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Atwood BK, Mackie K. CB2: a cannabinoid receptor with an identity crisis. Br J Pharmacol 2010. [PMID: 20590558 DOI: 10.1111/j.1476-5381] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
CB(2) was first considered to be the 'peripheral cannabinoid receptor'. This title was bestowed based on its abundant expression in the immune system and presumed absence from the central nervous system. However, multiple recent reports question the absence of CB(2) from the central nervous system. For example, it is now well accepted that CB(2) is expressed in brain microglia during neuroinflammation. However, the extent of CB(2) expression in neurons has remained controversial. There have been studies claiming either extreme-its complete absence to its widespread expression-as well as everything in between. This review will discuss the reported tissue distribution of CB(2) with a focus on CB(2) in neurons, particularly those in the central nervous system as well as the implications of that presence. As CB(2) is an attractive therapeutic target for pain management and immune system modulation without overt psychoactivity, defining the extent of its presence in neurons will have a significant impact on drug discovery. Our recommendation is to encourage cautious interpretation of data that have been presented for and against CB(2)'s presence in neurons and to encourage continued rigorous study.
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Affiliation(s)
- Brady K Atwood
- The Gill Center and the Department of Psychological & Brain Sciences, Indiana University, Bloomington, IN 47405, USA
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Abstract
CB(2) was first considered to be the 'peripheral cannabinoid receptor'. This title was bestowed based on its abundant expression in the immune system and presumed absence from the central nervous system. However, multiple recent reports question the absence of CB(2) from the central nervous system. For example, it is now well accepted that CB(2) is expressed in brain microglia during neuroinflammation. However, the extent of CB(2) expression in neurons has remained controversial. There have been studies claiming either extreme-its complete absence to its widespread expression-as well as everything in between. This review will discuss the reported tissue distribution of CB(2) with a focus on CB(2) in neurons, particularly those in the central nervous system as well as the implications of that presence. As CB(2) is an attractive therapeutic target for pain management and immune system modulation without overt psychoactivity, defining the extent of its presence in neurons will have a significant impact on drug discovery. Our recommendation is to encourage cautious interpretation of data that have been presented for and against CB(2)'s presence in neurons and to encourage continued rigorous study.
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Affiliation(s)
- Brady K Atwood
- The Gill Center and the Department of Psychological & Brain Sciences, Indiana University, Bloomington, IN 47405, USA
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