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Increased expression of CB2 receptor in the intestinal biopsies of children with inflammatory bowel disease. Pediatr Res 2023; 93:520-525. [PMID: 35717484 DOI: 10.1038/s41390-022-02109-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/10/2022] [Accepted: 04/13/2022] [Indexed: 11/09/2022]
Abstract
OBJECTIVES The Cannabinoid Receptor type 2 (CB2) is involved in inflammation and immune cell modulation. In previous studies, we demonstrated the association between the CNR2 rs35761398 polymorphism and the risk for pediatric inflammatory bowel disease (IBD). In this study, we analyzed the intestinal biopsies from Crohn disease (CD) and ulcerative colitis (UC) pediatric patients at the diagnosis to evaluate the expression of CB2 and several factors associated with IBD inflammatory pathways. METHODS We enrolled five patients with CD, five with UC, and five controls (CTR). We analyzed ileum and rectum biopsies from patients of each group evaluating the expression of CB2, Toll-like receptor 4, interleukin-6, and interleukin-1β by western blot and immunofluorescence. RESULTS Western blot analysis showed a significant increase of CB2 in the CD ileum and in the UC rectum biopsies and an increase of TLR4 in the UC rectum. We also observed a significant over-expression of the IL-6 in UC rectum. The immunofluorescence analysis confirmed western blot data, showing also a T-lymphocytes infiltration colocalized with CB2 expression in the CD ileum and UC rectum. CONCLUSIONS Our results show an upregulation of CB2 in pediatric IBD, which might have implications for drug discovery. IMPACT The Cannabinoid Receptor type 2 (CB2) is involved in the inflammation and modulation of the immune response in pediatric inflammatory bowel disease (IBD). CB2 receptor is more expressed in the inflamed intestine of pediatric IBD patients. CB2 could be used as a potential therapeutic target to reduce IBD-related inflammatory state in childhood.
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Thakur V, Bashashati M, Enriquez J, Chattopadhyay M. Inhibiting Fatty Acid Amide Hydrolase Ameliorates Enteropathy in Diabetic Mice: A Cannabinoid 1 Receptor Mediated Mechanism. Vet Sci 2022; 9:vetsci9070364. [PMID: 35878381 PMCID: PMC9319435 DOI: 10.3390/vetsci9070364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 07/09/2022] [Accepted: 07/13/2022] [Indexed: 11/16/2022] Open
Abstract
Gastrointestinal (GI) dysmotility in diabetics exhibits fecal incontinence or constipation which affects patients’ quality of life. In this study, we aimed to understand the pattern of GI transit in type 1 diabetic (T1D) mice and whether inhibiting endocannabinoid degradation would exhibit therapeutic effect. Whole gut-transit time and fecal-pellet output were measured at 16 week post-diabetes. T1D mice treated with fatty acid amide hydrolase (FAAH) inhibitor URB597 showed reduced fecal output as well as improved gut transit time. Cannabinoid 1 receptor antagonist, AM251 blocked the effects of URB597, which may demonstrate that FAAH inhibitor is a potential remedial strategy for GI dysmotility.
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Affiliation(s)
- Vikram Thakur
- Center of Emphasis in Diabetes and Metabolism, Department of Molecular and Translational Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA;
| | - Mohammad Bashashati
- Division of Gastroenterology, Department of Internal Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA;
| | - Josue Enriquez
- Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA;
| | - Munmun Chattopadhyay
- Center of Emphasis in Diabetes and Metabolism, Department of Molecular and Translational Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA;
- Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA;
- Correspondence:
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Abstract
Cannabinoids have been known as the primary component of cannabis for decades, but the characterization of the endocannabinoid system (ECS) in the 1990s opened the doors for cannabis' use in modern medicine. The 2 main receptors of this system, cannabinoid receptors 1 and 2, are found on cells of various tissues, with significant expression in the gastrointestinal (GI) tract. The characterization of the ECS also heralded the understanding of endocannabinoids, naturally occurring compounds synthesized in the human body. Via secondary signaling pathways acting on vagal nerves, nociceptors, and immune cells, cannabinoids have been shown to have both palliative and detrimental effects on the pathophysiology of GI disorders. Although research on the effects of both endogenous and exogenous cannabinoids has been slow due to the complicated legal history of cannabis, discoveries of cannabinoids' treatment potential have been found in various fields of medicine, including the GI world. Medical cannabis has since been offered as a treatment for a myriad of conditions and malignancies, including cancer, human immunodeficiency virus/acquired immunodeficiency syndrome, multiple sclerosis, chronic pain, nausea, posttraumatic stress disorder, amyotrophic lateral sclerosis, cachexia, glaucoma, and epilepsy. This article hopes to create an overview of current research on cannabinoids and the ECS, detail the potential advantages and pitfalls of their use in GI diseases, and explore possible future developments in this field.
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Chanda D, Neumann D, Glatz JFC. The endocannabinoid system: Overview of an emerging multi-faceted therapeutic target. Prostaglandins Leukot Essent Fatty Acids 2019; 140:51-56. [PMID: 30553404 DOI: 10.1016/j.plefa.2018.11.016] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/28/2018] [Accepted: 11/28/2018] [Indexed: 02/08/2023]
Abstract
The endocannabinoids anandamide (AEA) and 2-arachidonoylglyerol (2-AG) are endogenous lipid mediators that exert protective roles in pathophysiological conditions, including cardiovascular diseases. In this brief review, we provide a conceptual framework linking endocannabinoid signaling to the control of the cellular and molecular hallmarks, and categorize the key components of endocannabinoid signaling that may serve as targets for novel therapeutics. The emerging picture not only reinforces endocannabinoids as potent regulators of cellular metabolism but also reveals that endocannabinoid signaling is mechanistically more complex and diverse than originally thought.
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MESH Headings
- Amidohydrolases/antagonists & inhibitors
- Animals
- Arachidonic Acids/metabolism
- Autocrine Communication
- Cells/metabolism
- Dronabinol/pharmacology
- Endocannabinoids/metabolism
- Glycerides/metabolism
- Humans
- Mice
- Molecular Targeted Therapy
- Paracrine Communication
- Polyunsaturated Alkamides/metabolism
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/metabolism
- Swine
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Affiliation(s)
- Dipanjan Chanda
- Department of Genetics & Cell Biology, Faculty of Health, Medicine and Life Sciences (FHML), Maastricht University, Maastricht, The Netherlands; Current affiliation: Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Daegu, Republic of Korea
| | - Dietbert Neumann
- Department of Genetics & Cell Biology, Faculty of Health, Medicine and Life Sciences (FHML), Maastricht University, Maastricht, The Netherlands; Current affiliation: Department of Pathology, CARIM, Maastricht University Medical Center+ (MUMC+), Maastricht, the Netherlands
| | - Jan F C Glatz
- Department of Genetics & Cell Biology, Faculty of Health, Medicine and Life Sciences (FHML), Maastricht University, Maastricht, The Netherlands.
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Andrews CN, Devlin SM, Le Foll B, Fischer B, Tse F, Storr M, Congly SE. Canadian Association of Gastroenterology Position Statement: Use of Cannabis in Gastroenterological and Hepatic Disorders. J Can Assoc Gastroenterol 2018; 2:37-43. [PMID: 31294362 PMCID: PMC6507278 DOI: 10.1093/jcag/gwy064] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 10/17/2018] [Indexed: 12/19/2022] Open
Affiliation(s)
- Christopher N Andrews
- Division of Gastroenterology and Hepatology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Correspondence: Christopher N Andrews, MD, MSc, FRCPC, Clinical Professor, Division of Gastroenterology and Hepatology, Cumming School of Medicine, University of Calgary, 6th Floor, TRW Building, 3280 Hospital Drive NW, Calgary, AB T2N 4Z6, Canada. E-mail
| | - Shane M Devlin
- Division of Gastroenterology and Hepatology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Acute Care Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Departments of Family and Community Medicine, Pharmacology and Toxicology, Psychiatry, Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Benedikt Fischer
- Institute for Mental Health Policy Research, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Frances Tse
- Department of Gastroenterology and Hepatology, McMaster University, Hamilton, Ontario, Canada
| | - Martin Storr
- Department of Medicine, University of Munich and Center of Endoscopy, Starnberg, Germany
| | - Stephen E Congly
- Division of Gastroenterology and Hepatology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Bashashati M, Fichna J, Piscitelli F, Capasso R, Izzo AA, Sibaev A, Timmermans JP, Cenac N, Vergnolle N, Di Marzo V, Storr M. Targeting fatty acid amide hydrolase and transient receptor potential vanilloid-1 simultaneously to modulate colonic motility and visceral sensation in the mouse: A pharmacological intervention with N-arachidonoyl-serotonin (AA-5-HT). Neurogastroenterol Motil 2017; 29. [PMID: 28695708 DOI: 10.1111/nmo.13148] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 06/02/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Endocannabinoid anandamide (AEA) inhibits intestinal motility and visceral pain, but it may also be proalgesic through transient receptor potential vanilloid-1 (TRPV1). AEA is degraded by fatty acid amide hydrolase (FAAH). This study explored whether dual inhibition of FAAH and TRPV1 reduces diarrhea and abdominal pain. METHODS Immunostaining was performed on myenteric plexus of the mouse colon. The effects of the dual FAAH/TRPV1 inhibitor AA-5-HT on electrically induced contractility, excitatory junction potential (EJP) and fast (f) and slow (s) inhibitory junction potentials (IJP) in the mouse colon, colonic propulsion and visceromotor response (VMR) to rectal distension were studied. The colonic levels of endocannabinoids and fatty acid amides were measured. KEY RESULTS CB1-positive neurons exhibited TRPV1; only some TRPV1 positive neurons did not express CB1. CB1 and FAAH did not colocalize. AA-5-HT (100 nM-10 μM) decreased colonic contractility by ~60%; this effect was abolished by TRPV1 antagonist 5'-IRTX, but not by CB1 antagonist, SR141716. AA-5-HT (1 μM-10 μM) inhibited EJP by ~30% and IJPs by ~50%. The effects of AA-5-HT on junction potentials were reversed by SR141716 and 5`-IRTX. AA-5-HT (20 mg/kg; i.p.) inhibited colonic propulsion by ~30%; SR141716 but not 5`-IRTX reversed this effect. AA-5-HT decreased VMR by ~50%-60%; these effects were not blocked by SR141716 or 5`-IRTX. AA-5-HT increased AEA in the colon. CONCLUSIONS AND INFERENCES The effects of AA-5-HT on visceral sensation and colonic motility are differentially mediated by CB1, TRPV1 and non-CB1/TRPV1 mechanisms, possibly reflecting the distinct neuromodulatory roles of endocannabinoid and endovanilloid FAAH substrates in the mouse intestine.
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Affiliation(s)
- M Bashashati
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada.,Division of Gastroenterology, Department of Internal Medicine, Texas Tech University Health Sciences Center/Paul L. Foster School of Medicine, El Paso, TX, USA
| | - J Fichna
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada.,Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - F Piscitelli
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Pozzuoli, Italy
| | - R Capasso
- Department of Agricultural Sciences, University of Naples Federico II, Portici Italy and Endocannabinoid Research Group, Naples, Italy
| | - A A Izzo
- Department of Pharmacy, University of Naples Federico II and Endocannabinoid Research Group, Naples, Italy
| | - A Sibaev
- Department of Internal Medicine II, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Munich, Germany
| | - J-P Timmermans
- Laboratory of Cell Biology and Histology, University of Antwerp, Antwerp, Belgium
| | - N Cenac
- Inserm, U1220, Toulouse, France.,Institut de Recherche en Sante Digestive (IRSD), Université de Toulouse, Université Paul Sabatier, Toulouse, France.,Department of Pharmacology and Physiology, University of Calgary, Calgary, AB, Canada
| | - N Vergnolle
- Inserm, U1220, Toulouse, France.,Institut de Recherche en Sante Digestive (IRSD), Université de Toulouse, Université Paul Sabatier, Toulouse, France.,Department of Pharmacology and Physiology, University of Calgary, Calgary, AB, Canada
| | - V Di Marzo
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Pozzuoli, Italy
| | - M Storr
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada.,Department of Internal Medicine II, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Munich, Germany.,Center of Endoscopy, Starnberg, Germany.,Division of Gastroenterology and Department of Medicine, University of Calgary, Calgary, AB, Canada
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Zhao X, Liang P, Liu J, Jiang H, Fan X, Chen G, Zhou C. Elevation of arachidonoylethanolamide levels by activation of the endocannabinoid system protects against colitis and ameliorates remote organ lesions in mice. Exp Ther Med 2017; 14:5664-5670. [PMID: 29285108 DOI: 10.3892/etm.2017.5222] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 06/29/2017] [Indexed: 02/07/2023] Open
Abstract
The endocannabinoid system (ECS) is a potential pharmaceutical target for the treatment of inflammatory bowel diseases (IBDs). The aim of this study was to explore the effects of activation of the ECS on IBD and the associated neural inflammation-induced disruption of the blood-brain barrier (BBB). In a mouse model of trinitrobenzene sulfonic acid-induced colitis, the inhibition of fatty acid amide hydrolase with URB597 elevated the arachidonoylethanolamide concentration of the colon. Macroscopic alterations of the colons were evaluated, and the 7-day survival rate of mice was analyzed. BBB integrity was assessed using a dye tracer method, and the cognitive function of mice was examined using a fear-conditioning test. URB597 treatment significantly reduced macroscopic alterations of the colon, decreased the mortality rate, and protected the integrity of the BBB in the mice (P<0.05). No significant changes were observed in the cognitive functions of the mice (P>0.05); therefore, the neuroprotective effect of ECS in this colitis model requires further investigation. Activation of the ECS was efficient in ameliorating colitis and increasing the survival rate of the mice, and reducing remote organ changes induced by colitis. The results suggest that modulation of the ECS is a potential therapeutic approach for IBDs and the associated remote organ lesions.
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Affiliation(s)
- Xiaolin Zhao
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,West China School of Pharmacy, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Peng Liang
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Jin Liu
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Haixia Jiang
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, The First Affiliated Hospital of Kunming Medical University, Yunnan, Kunming 650221, P.R. China
| | - Xiaoshuai Fan
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Guo Chen
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Cheng Zhou
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
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Piazza PV, Cota D, Marsicano G. The CB1 Receptor as the Cornerstone of Exostasis. Neuron 2017; 93:1252-1274. [PMID: 28334603 DOI: 10.1016/j.neuron.2017.02.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 01/30/2017] [Accepted: 01/31/2017] [Indexed: 01/07/2023]
Abstract
The type-1 cannabinoid receptor (CB1) is the main effector of the endocannabinoid system (ECS), which is involved in most brain and body functions. In this Perspective, we provide evidence indicating that CB1 receptor functions are key determinants of bodily coordinated exostatic processes. First, we will introduce the concepts of endostasis and exostasis as compensation or accumulation for immediate or future energy needs and discuss how exostasis has been necessary for the survival of species during evolution. Then, we will argue how different specific biological functions of the CB1 receptor in the body converge to provide physiological exostatic processes. Finally, we will introduce the concept of proactive evolution-induced diseases (PEIDs), which helps explain the seeming paradox that an evolutionary-selected physiological function can become the cause of epidemic pathological conditions, such as obesity. We propose here a possible unifying theory of CB1 receptor functions that can be tested by future experimental studies.
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Affiliation(s)
- Pier Vincenzo Piazza
- INSERM, NeuroCentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33077 Bordeaux, France; University of Bordeaux, NeuroCentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33077 Bordeaux, France.
| | - Daniela Cota
- INSERM, NeuroCentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33077 Bordeaux, France; University of Bordeaux, NeuroCentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33077 Bordeaux, France
| | - Giovanni Marsicano
- INSERM, NeuroCentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33077 Bordeaux, France; University of Bordeaux, NeuroCentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33077 Bordeaux, France.
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Abstract
OPINION STATEMENT Despite the political and social controversy affiliated with it, the medical community must come to the realization that cannabinoids exist as a ubiquitous signaling system in many organ systems. Our understanding of cannabinoids and how they relate not only to homeostasis but also in disease states must be furthered through research, both clinically and in the laboratory. The identification of the cannabinoid receptors in the early 1990s have provided us with the perfect target of translational research. Already, much has been done with cannabinoids and the nervous system. Here, we explore the implications it has for the gastrointestinal tract. Most therapeutics currently on the market presently target only one aspect of the cannabinoid system. Our main purpose here is to highlight areas of research and potential avenues of discovery that the cannabinoid system has yet to reveal.
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Affiliation(s)
- Zachary Wilmer Reichenbach
- Center for Substance Abuse Research (CSAR), Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,Section of Gastroenterology, Department of Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Ron Schey
- Section of Gastroenterology, Department of Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.
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Trautmann SM, Sharkey KA. The Endocannabinoid System and Its Role in Regulating the Intrinsic Neural Circuitry of the Gastrointestinal Tract. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 125:85-126. [PMID: 26638765 DOI: 10.1016/bs.irn.2015.10.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Endocannabinoids are important neuromodulators in the central nervous system. They regulate central transmission through pre- and postsynaptic actions on neurons and indirectly through effects on glial cells. Cannabinoids (CBs) also regulate neurotransmission in the enteric nervous system (ENS) of the gastrointestinal (GI) tract. The ENS consists of intrinsic primary afferent neurons, interneurons, and motor neurons arranged in two ganglionated plexuses which control all the functions of the gut. Increasing evidence suggests that endocannabinoids are potent neuromodulators in the ENS. In this review, we will highlight key observations on the localization of CB receptors and molecules involved in the synthesis and degradation of endocannabinoids in the ENS. We will discuss endocannabinoid signaling mechanisms, endocannabinoid tone and concepts of CB receptor metaplasticity in the ENS. We will also touch on some examples of enteric neural signaling in relation neuromuscular, secretomotor, and enteroendocrine transmission in the ENS. Finally, we will briefly discuss some key future directions.
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Affiliation(s)
- Samantha M Trautmann
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Keith A Sharkey
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
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Keenan CM, Storr MA, Thakur GA, Wood JT, Wager-Miller J, Straiker A, Eno MR, Nikas SP, Bashashati M, Hu H, Mackie K, Makriyannis A, Sharkey KA. AM841, a covalent cannabinoid ligand, powerfully slows gastrointestinal motility in normal and stressed mice in a peripherally restricted manner. Br J Pharmacol 2015; 172:2406-18. [PMID: 25572435 DOI: 10.1111/bph.13069] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/19/2014] [Accepted: 01/02/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Cannabinoid (CB) ligands have been demonstrated to have utility as novel therapeutic agents for the treatment of pain, metabolic conditions and gastrointestinal (GI) disorders. However, many of these ligands are centrally active, which limits their usefulness. Here, we examine a unique novel covalent CB receptor ligand, AM841, to assess its potential for use in physiological and pathophysiological in vivo studies. EXPERIMENTAL APPROACH The covalent nature of AM841 was determined in vitro using electrophysiological and receptor internalization studies on isolated cultured hippocampal neurons. Mouse models were used for behavioural analysis of analgesia, hypothermia and hypolocomotion. The motility of the small and large intestine was assessed in vivo under normal conditions and after acute stress. The brain penetration of AM841 was also determined. KEY RESULTS AM841 behaved as an irreversible CB1 receptor agonist in vitro. AM841 potently reduced GI motility through an action on CB1 receptors in the small and large intestine under physiological conditions. AM841 was even more potent under conditions of acute stress and was shown to normalize accelerated GI motility under these conditions. This compound behaved as a peripherally restricted ligand, showing very little brain penetration and no characteristic centrally mediated CB1 receptor-mediated effects (analgesia, hypothermia or hypolocomotion). CONCLUSIONS AND IMPLICATIONS AM841, a novel peripherally restricted covalent CB1 receptor ligand that was shown to be remarkably potent, represents a new class of potential therapeutic agents for the treatment of functional GI disorders.
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Affiliation(s)
- C M Keenan
- Hotchkiss Brain Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Alberta, Canada; Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
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