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Yates ML, Barker EL. Inactivation and Biotransformation of the Endogenous Cannabinoids Anandamide and 2-Arachidonoylglycerol. Mol Pharmacol 2009; 76:11-7. [DOI: 10.1124/mol.109.055251] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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52
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Coomber B, O'Donoghue MF, Mason R. Inhibition of endocannabinoid metabolism attenuates enhanced hippocampal neuronal activity induced by kainic acid. Synapse 2009; 62:746-55. [PMID: 18651640 DOI: 10.1002/syn.20547] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The endogenous cannabinoid system regulates neuronal excitability. The effects of inhibiting fatty acid amide hydrolase (FAAH), the enzyme responsible for metabolism of the endocannabinoid anandamide, on kainic acid (KA)-induced neuronal activity were investigated in the rat in vivo, using the selective FAAH inhibitor URB597. Hippocampal neuronal ensemble unit activity was recorded in isoflurane-anesthetized rats using 16-wire microelectrode arrays. Separate groups of rats were administered with single doses of KA alone, KA and URB597 (0.3 or 1 mg kg(-1), i.p.), or URB597 (1 mg kg(-1)) alone. The role of the cannabinoid CB1 receptor in mediating the effects of URB597 was explored using the CB1 selective antagonists AM251, either alone or prior to KA and URB597 (1 mg kg(-1)) administration, and SR141716A, administered prior to KA and URB597 (1 mg kg(-1)). Neuronal firing and burst firing rates were examined in animals with confirmed dorsal hippocampal placements. KA induced an increase in both firing and burst firing rates, effects which were attenuated by URB597 in a dose-related manner. Pretreatment with AM251 or SR141716A partly attenuated the URB597-mediated effects on firing and burst firing rate. Rats treated with AM251 or URB597 alone did not exhibit any significant change in either firing or burst firing rates compared with basal activity. These results suggest that the inhibition of endocannabinoid metabolism can suppress hyperexcitability in the rat hippocampus, partly via a CB1 receptor-mediated mechanism.
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Affiliation(s)
- Ben Coomber
- School of Biomedical Sciences, University of Nottingham, Nottingham, United Kingdom.
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53
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Malcher-Lopes R, Buzzi M. Glucocorticoid-regulated crosstalk between arachidonic acid and endocannabinoid biochemical pathways coordinates cognitive-, neuroimmune-, and energy homeostasis-related adaptations to stress. VITAMINS AND HORMONES 2009; 81:263-313. [PMID: 19647116 DOI: 10.1016/s0083-6729(09)81011-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Arachidonic acid and its derivatives constitute the major group of signaling molecules involved in the innate immune response and its communication with all cellular and systemic aspects involved on homeostasis maintenance. Glucocorticoids spread throughout the organism their influences over key enzymatic steps of the arachidonic acid biochemical pathways, leading, in the central nervous system, to a shift favoring the synthesis of anti-inflammatory endocannabinoids over proinflammatory metabolites, such as prostaglandins. This shift modifies local immune-inflammatory response and neuronal activity to ultimately coordinate cognitive, behavioral, neuroendocrine, neuroimmune, physiological, and metabolic adjustments to basal and stress conditions. In the hypothalamus, a reciprocal feedback between glucocorticoids and arachidonate-containing molecules provides a mechanism for homeostatic control. This neurochemical switch is susceptible to fine-tuning by neuropeptides, cytokines, and hormones, such as leptin and interleukin-1beta, assuring functional integration between energy homeostasis control and the immune/stress response.
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Affiliation(s)
- Renato Malcher-Lopes
- Laboratory of Mass Spectrometry, EMBRAPA-Center for Genetic Resources and Biotechnology, Brasília-DF, Brazil
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54
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Chapter 2 Organized Trafficking of Anandamide and Related Lipids. VITAMINS AND HORMONES 2009; 81:25-53. [DOI: 10.1016/s0083-6729(09)81002-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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55
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Waldeck-Weiermair M, Zoratti C, Osibow K, Balenga N, Goessnitzer E, Waldhoer M, Malli R, Graier WF. Integrin clustering enables anandamide-induced Ca2+ signaling in endothelial cells via GPR55 by protection against CB1-receptor-triggered repression. J Cell Sci 2008; 121:1704-1717. [PMID: 18445684 PMCID: PMC4067516 DOI: 10.1242/jcs.020958] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Although the endocannabinoid anandamide is frequently described to act predominantly in the cardiovascular system, the molecular mechanisms of its signaling remained unclear. In human endothelial cells, two receptors for anandamide were found, which were characterized as cannabinoid 1 receptor (CB1R; CNR1) and G-protein-coupled receptor 55 (GPR55). Both receptors trigger distinct signaling pathways. It crucially depends on the activation status of integrins which signaling cascade becomes promoted upon anandamide stimulation. Under conditions of inactive integrins, anandamide initiates CB1R-derived signaling, including Gi-protein-mediated activation of spleen tyrosine kinase (Syk), resulting in NFkappaB translocation. Furthermore, Syk inhibits phosphoinositide 3-kinase (PI3K) that represents a key protein in the transduction of GPR55-originated signaling. However, once integrins are clustered, CB1R splits from integrins and, thus, Syk cannot further inhibit GPR55-triggered signaling resulting in intracellular Ca2+ mobilization from the endoplasmic reticulum (ER) via a PI3K-Bmx-phospholipase C (PLC) pathway and activation of nuclear factor of activated T-cells. Altogether, these data demonstrate that the physiological effects of anandamide on endothelial cells depend on the status of integrin clustering.
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Affiliation(s)
| | - Cristina Zoratti
- Institute of Molecular Biology and Biochemistry, Medical University Graz, Graz, A8010, Austria
| | - Karin Osibow
- Institute of Molecular Biology and Biochemistry, Medical University Graz, Graz, A8010, Austria
| | - Nariman Balenga
- Institute of Experimental and Clinical Pharmacology, Medical University Graz, Graz, A8010, Austria
| | - Edith Goessnitzer
- Institute of Pharmaceutical Chemistry, University Graz, Graz Austria
| | - Maria Waldhoer
- Institute of Experimental and Clinical Pharmacology, Medical University Graz, Graz, A8010, Austria
| | - Roland Malli
- Institute of Molecular Biology and Biochemistry, Medical University Graz, Graz, A8010, Austria
| | - Wolfgang F. Graier
- Institute of Molecular Biology and Biochemistry, Medical University Graz, Graz, A8010, Austria
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56
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Battista N, Pasquariello N, Di Tommaso M, Maccarrone M. Interplay between endocannabinoids, steroids and cytokines in the control of human reproduction. J Neuroendocrinol 2008; 20 Suppl 1:82-9. [PMID: 18426505 DOI: 10.1111/j.1365-2826.2008.01684.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The use of marijuana, which today is the most used recreational drug, has been demonstrated to affect adversely reproduction. Marijuana smokers, both men and women, show impaired fertility, owing to defective signalling pathways, aberrant hormonal regulation, or wrong timing during embryo implantation. Anandamide (N-arachidonoylethanolamine, AEA) and 2-arachidonoylglycerol (2-AG) mimic Delta(9)-tetrahydrocannabinol (THC), the psychoactive principle of Cannabis sativa, by binding to both the brain-type (CB(1)) and the spleen-type (CB(2)) cannabinoid receptors. These 'endocannabinoids' exert several actions either in the central nervous system or in peripheral tissues, and are metabolised by specific enzymes that synthesise or hydrolyse them. In this review, we shall describe the elements that constitute the endocannabinoid system (ECS), in order to put in a better perspective the role of this system in the control of human fertility, both in females and males. In addition, we shall discuss the interplay between ECS, sex hormones and cytokines, which generates an endocannabinoid-hormone-cytokine array critically involved in the control of human reproduction.
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Affiliation(s)
- N Battista
- Department of Biomedical Sciences, University of Teramo, Teramo, Italy
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57
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Battista N, Rapino C, Di Tommaso M, Bari M, Pasquariello N, Maccarrone M. Regulation of male fertility by the endocannabinoid system. Mol Cell Endocrinol 2008; 286:S17-23. [PMID: 18328619 DOI: 10.1016/j.mce.2008.01.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 01/16/2008] [Accepted: 01/16/2008] [Indexed: 10/22/2022]
Abstract
Mammalian conception is a complex process regulated by both sexual behavior and reproductive performance. Alcohol, marijuana and tobacco are among the main factors which affect negatively fertility in women and men. Several studies have demonstrated that marijuana impairs the male copulatory activity, and that smokers of this illegal drug show reduced fertility due, for instance, to decrease in sperm concentration, defective sperm function or alteration of sperm morphology. The discovery of endocannabinoids and all components responsible for their metabolism has allowed to collect valuable information on the effects of these endogenous lipids, able to mimic the actions of delta-9-tetrahydrocannabinol (THC), in reproductive functions. The purpose of this review is to describe the actions of cannabinoids and endocannabinoids on the control of procreation and hormonal release during the fertilization process in males.
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Affiliation(s)
- Natalia Battista
- Department of Biomedical Sciences, University of Teramo, Teramo, Italy
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58
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Fezza F, Oddi S, Di Tommaso M, De Simone C, Rapino C, Pasquariello N, Dainese E, Finazzi-Agrò A, Maccarrone M. Characterization of biotin-anandamide, a novel tool for the visualization of anandamide accumulation. J Lipid Res 2008; 49:1216-23. [PMID: 18316795 DOI: 10.1194/jlr.m700486-jlr200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Anandamide (N-arachidonoylethanolamide; AEA) acts as an endogenous agonist of both cannabinoid and vanilloid receptors. During the last two decades, its metabolic pathways and biological activity have been investigated extensively and relatively well characterized. In contrast, at present, the effective nature and mechanism of AEA transport remain controversial and still unsolved issues. Here, we report the characterization of a biotinylated analog of AEA (b-AEA) that has the same lipophilicity of the parent compound. In addition, by means of biochemical assays and fluorescence microscopy, we show that b-AEA is accumulated inside the cells in a way superimposable on that of AEA. Conversely, b-AEA does not interact or interfere with the other components of the endocannabinoid system, such as type-1 and type-2 cannabinoid receptors, vanilloid receptor, AEA synthetase (N-acylphosphatidylethanolamine-hydrolyzing phospholipase D), or AEA hydrolase (fatty acid amide hydrolase). Together, our data suggest that b-AEA could be a very useful probe for visualizing the accumulation and intracellular distribution of this endocannabinoid.
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Affiliation(s)
- Filomena Fezza
- European Center for Brain Research/Istituto di Ricovero e Cura a Carattere Scientifico S. Lucia Foundation, Rome, Italy
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Malcher-Lopes R, Franco A, Tasker JG. Glucocorticoids shift arachidonic acid metabolism toward endocannabinoid synthesis: a non-genomic anti-inflammatory switch. Eur J Pharmacol 2008; 583:322-39. [PMID: 18295199 DOI: 10.1016/j.ejphar.2007.12.033] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Revised: 12/12/2007] [Accepted: 12/16/2007] [Indexed: 11/24/2022]
Abstract
Glucocorticoids are capable of exerting both genomic and non-genomic actions in target cells of multiple tissues, including the brain, which trigger an array of electrophysiological, metabolic, secretory and inflammatory regulatory responses. Here, we have attempted to show how glucocorticoids may generate a rapid anti-inflammatory response by promoting arachidonic acid-containing endocannabinoids biosynthesis. According to our hypothesized model, non-genomic action of glucocorticoids results in the global shift of membrane lipid metabolism, subverting metabolic pathways toward the synthesis of the anti-inflammatory endocannabinoids, anandamide (AEA) and 2-arachidonoyl-glycerol (2-AG), and away from arachidonic acid production. Post-transcriptional inhibition of cyclooxygenase-2 (COX(2)) synthesis by glucocorticoids assists this mechanism by suppressing the synthesis of pro-inflammatory prostaglandins as well as endocannabinoid-derived prostanoids. In the central nervous system (CNS) this may represent a major neuroprotective system, which may cross-talk with leptin signaling in the hypothalamus allowing for the coordination between energy homeostasis and the inflammatory response.
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60
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Retrograde endocannabinoid signaling at striatal synapses requires a regulated postsynaptic release step. Proc Natl Acad Sci U S A 2007; 104:20564-9. [PMID: 18077376 DOI: 10.1073/pnas.0706873104] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Endocannabinoids (eCBs) mediate short- and long-term depression of synaptic strength by retrograde transsynaptic signaling. Previous studies have suggested that an eCB mobilization or release step in the postsynaptic neuron is involved in this retrograde signaling. However, it is not known whether this release process occurs automatically upon eCB synthesis or whether it is regulated by other synaptic factors. To address this issue, we loaded postsynaptic striatal medium spiny neurons (MSNs) with the eCBs anandamide (AEA) or 2-arachidonoylglycerol and determined the conditions necessary for presynaptic inhibition. We found that presynaptic depression of glutamatergic excitatory postsynaptic currents (EPSCs) and GABAergic inhibitory postsynaptic currents (IPSCs) induced by postsynaptic eCB loading required a certain level of afferent activation that varied between the different synaptic types. Synaptic depression at excitatory synapses was temperature-dependent and blocked by the eCB membrane transport blockers, VDM11 and UCM707, but did not require activation of metabotropic glutamate receptors, l-calcium channels, nitric oxide, voltage-activated Na(+) channels, or intracellular calcium. Application of the CB(1)R antagonist, AM251, after depression was established, reversed the decrease in EPSC, but not in IPSC, amplitude. Direct activation of the CB(1) receptor by WIN 55,212-2 initiated synaptic depression that was independent of afferent stimulation. These findings indicate that retrograde eCB signaling requires a postsynaptic release step involving a transporter or carrier that is activated by afferent stimulation/synaptic activation.
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La Rana G, Russo R, D'Agostino G, Sasso O, Raso GM, Iacono A, Meli R, Piomelli D, Calignano A. AM404, an anandamide transport inhibitor, reduces plasma extravasation in a model of neuropathic pain in rat: role for cannabinoid receptors. Neuropharmacology 2007; 54:521-9. [PMID: 18093621 DOI: 10.1016/j.neuropharm.2007.10.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 10/04/2007] [Accepted: 10/31/2007] [Indexed: 10/22/2022]
Abstract
Neuropathic pain consequent to peripheral nerve injury has been associated with local inflammation. Following noxious stimulation afferent fibres release substance P (SP) and calcitonin-gene related peptide (CGRP), which are closely related to oedema formation and plasma leakage. The effect of the anandamide transport blocker AM404 has been studied on plasma extravasation after chronic constriction injury (CCI) which consists in a unilateral loose ligation of the rat sciatic nerve (Bennett and Xie, 1988). AM404 (1-3-10 mg kg(-1)) reduced plasma extravasation in the legated paw, measured as mug of Evans Blue per gram of fresh tissue. A strong effect on vascular permeability was also produced by the synthetic cannabinoid agonist WIN 55,212-2 (0.1-0.3-1 mg kg(-1)). Using specific antagonists or enzyme inhibitors, we demonstrate that cannabinoids act at several levels: data on the 3rd day suggest a strong involvement of substance P (SP) and calcitonin gene-related peptide (CGRP) in the control of vascular tone, whereas at the 7th and 14th days the major role seems to be played by prostaglandins (PGs) and nitric oxide (NO). Capsaicin injection in ligated paws of AM404- or WIN 55,212-2-treated rats resulted in an increase of Evans Blue extravasation, suggesting the involvement of the cannabinergic system in the protective effect of C fibres of ligated paws. Taken together, these data demonstrate the efficacy of cannabinoids in controlling pain behaviour through the modulation of several pain mediators and markers of vascular reactivity, such as SP, CGRP, PGs and NO.
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Affiliation(s)
- G La Rana
- Department of Experimental Pharmacology, University of Naples Federico II, via D. Montesano 49, 80131 Naples, Italy
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62
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Mukhopadhyay S, Tulis DA. Endocannabinoid regulation of matrix metalloproteinases: implications in ischemic stroke. Cardiovasc Hematol Agents Med Chem 2007; 5:311-8. [PMID: 17979695 PMCID: PMC3638791 DOI: 10.2174/187152507782109917] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Stroke is a major cause of morbidity and mortality and follows heart disease and cancer as the third leading cause of death in Western societies [1]. Despite many advances in stroke research and pharmacotherapy, clinical treatment of this debilitating disorder is still inadequate. Recent findings from several laboratories have identified the endocannabinoid signaling pathway, comprised of the endocannabinoid agonist anandamide and its pharmacological targets, CB1 and CB2 cannabinoid receptors and associated anandamide receptors, as a physiological system with capacity to mitigate cardiovascular and cerebrovascular disorders through neuronal and endothelial actions. Variability in experimental stroke models and modes of outcome evaluation, however, have provoked controversy regarding the precise roles of endocannabinoid signals in mediating neural and/or vascular protection versus neurovascular damage. Clinical trials of the CB1 antagonist rimonabant demonstrate that modulation of endocannabinoid signaling during metabolic regulation of vascular disorders can significantly impact clinical outcomes, thus providing strong argument for therapeutic utility of endocannabinoids and/or cannabinoid receptors as targets for therapeutic intervention in cases of stroke and associated vascular disorders. The purpose of this review is to provide updated information from basic science and clinical perspectives on endocannabinoid ligands and their effects in the pathophysiologic genesis of stroke. Particular emphasis will be placed on the endocannabinoids anandamide and 2-arachidonylglycerol and CB1 receptor-mediated mechanisms in the neurovascular unit during stroke pathogenesis. Deficiencies in our knowledge of endocannabinoids in the etiology and pathogenesis of stroke, caveats and limitations of existing studies, and future directions for investigation will be addressed.
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Bari M, Oddi S, De Simone C, Spagnolo P, Gasperi V, Battista N, Centonze D, Maccarrone M. Type-1 cannabinoid receptors colocalize with caveolin-1 in neuronal cells. Neuropharmacology 2007; 54:45-50. [PMID: 17714745 PMCID: PMC2706320 DOI: 10.1016/j.neuropharm.2007.06.030] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 06/26/2007] [Accepted: 06/26/2007] [Indexed: 11/22/2022]
Abstract
Type-1 (CB1) and type-2 (CB2) cannabinoid receptors belong to the rhodopsin family of G protein-coupled receptors, and are activated by endogenous lipids termed “endocannabinoids”. Recent reports have demonstrated that CB1R, unlike CB2R and other receptors and metabolic enzymes of endocannabinoids, functions in the context of lipid rafts, i.e. plasma membrane microdomains which may be important in modulating signal transduction. Here, we present novel data based on cell subfractionation, immunoprecipitation and confocal microscopy studies, that show that in C6 cells CB1R co-localizes almost entirely with caveolin-1. We also show that trafficking of CB1R in response to the raft disruptor methyl-β-cyclodextrin (MCD) is superimposable on that of caveolin-1, and that MCD treatment increases the accessibility of CB1R to its specific antibodies. These findings may be relevant for the manifold CB1R-dependent activities of endocannabinoids, like the regulation of apoptosis and of neurodegenerative diseases.
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Affiliation(s)
- Monica Bari
- Department of Experimental Medicine and Biochemical Sciences, University of Rome ‘Tor Vergata’, 00133 Rome, Italy
| | - Sergio Oddi
- European Center for Brain Research (CERC)/IRCCS, S. Lucia Foundation, 00196 Rome, Italy
- Department of Biomedical Sciences, University of Teramo, 64100 Teramo, Italy
| | - Chiara De Simone
- Department of Experimental Medicine and Biochemical Sciences, University of Rome ‘Tor Vergata’, 00133 Rome, Italy
- European Center for Brain Research (CERC)/IRCCS, S. Lucia Foundation, 00196 Rome, Italy
| | - Paola Spagnolo
- Department of Experimental Medicine and Biochemical Sciences, University of Rome ‘Tor Vergata’, 00133 Rome, Italy
| | - Valeria Gasperi
- European Center for Brain Research (CERC)/IRCCS, S. Lucia Foundation, 00196 Rome, Italy
- Department of Biomedical Sciences, University of Teramo, 64100 Teramo, Italy
| | - Natalia Battista
- Department of Biomedical Sciences, University of Teramo, 64100 Teramo, Italy
| | - Diego Centonze
- European Center for Brain Research (CERC)/IRCCS, S. Lucia Foundation, 00196 Rome, Italy
- Neurologic Clinics, Department of Neurosciences, University of Rome ‘Tor Vergata’, 00133 Rome, Italy
| | - Mauro Maccarrone
- European Center for Brain Research (CERC)/IRCCS, S. Lucia Foundation, 00196 Rome, Italy
- Department of Biomedical Sciences, University of Teramo, 64100 Teramo, Italy
- Corresponding author. Department of Biomedical Sciences, University of Teramo, Piazza A. Moro 45, 64100 Teramo, Italy. Tel.: +39 0861 266875; fax: +39 0861 266877.
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64
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An Overview on the Biochemistry of the Cannabinoid System. Mol Neurobiol 2007; 36:3-14. [DOI: 10.1007/s12035-007-0015-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Accepted: 05/24/2007] [Indexed: 12/29/2022]
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65
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Taylor AH, Ang C, Bell SC, Konje JC. The role of the endocannabinoid system in gametogenesis, implantation and early pregnancy. Hum Reprod Update 2007; 13:501-13. [PMID: 17584820 DOI: 10.1093/humupd/dmm018] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Maternal use of marijuana, in which the exocannabinoid Delta(9)-tetrahydrocannabinol is the most active psychoactive ingredient, is known to have adverse effects on various aspects of reproduction including ovulation, spermatogenesis, implantation and pregnancy duration. Endogenous cannabinoids of which Anandamide is the prototype are widely distributed in the body especially in the reproductive tract and pregnancy tissues and act through the same receptors as the receptor as Delta(9)-tetrahydrocannabinol. Anandamide, has been reported to have pleiotropic effects on human reproduction and in experimental animal models. It appears to be the important neuro-cytokine mediator synchronizing the embryo-endometrial development for timed implantation, the development of the embryo into the blastocyst and transport of the embryo across the fallopian tubes. The mechanisms by which it exerts these effects are unclear but could be via direct actions on the various sites within the reproductive system or its differential actions on vascular tone dependent. In this review article we bring together the current knowledge on the role of endoccanabinoids in reproduction and postulate on the potential mechanisms on how these affect reproduction. In addition, we examine its role on the endothelium and vascular smooth muscle as a potential mechanism for adverse pregnancy outcome.
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Affiliation(s)
- A H Taylor
- Department of Cancer Studies and Molecular Medicine, Robert Kilpatrick Clinical Sciences Building, University of Leicester, Leicester Royal Infirmary, PO Box 65, Leicester, Leicestershire LE2 7LX, UK
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Abstract
Oleamide (cis-9,10-octadecenoamide), a fatty acid primary amide discovered in the cerebrospinal fluid of sleep-deprived cats, has a variety of actions that give it potential as a signaling molecule, although these actions have not been extensively investigated in the cardiovascular system. The synthetic pathway probably involves synthesis of oleoylglycine and then conversion to oleamide by peptidylglycine alpha-amidating monooxygenase (PAM); breakdown of oleamide is by fatty acid amide hydrolase (FAAH). Oleamide interacts with voltage-gated Na(+) channels and allosterically with GABA(A) and 5-HT(7) receptors as well as having cannabinoid-like actions. The latter have been suggested to be due to potentiation of the effects of endocannabinoids such as anandamide by inhibiting FAAH-mediated hydrolysis. This might underlie an "entourage effect" whereby co-released endogenous nonagonist congeners of endocannabinoids protect the active molecule from hydrolysis by FAAH. However, oleamide has direct agonist actions at CB(1) cannabinoid receptors and also activates the TRPV1 vanilloid receptor. Other actions include inhibition of gap-junctional communication, and this might give oleamide a role in myocardial development. Many of these actions are absent from the trans isomer of 9,10-octadecenoamide. One of the most potent actions of oleamide is vasodilation. In rat small mesenteric artery the response does not involve CB(1) cannabinoid receptors but another pertussis toxin-sensitive, G protein-coupled receptor, as yet unidentified. This receptor is sensitive to rimonabant and O-1918, an antagonist at the putative "abnormal-cannabidiol" or endothelial "anandamide" receptors. Vasodilation is mediated by endothelium-derived nitric oxide, endothelium-dependent hyperpolarization, and also through activation of TRPV1 receptors. A physiological role for oleamide in the heart and circulation has yet to be demonstrated, as has production by cells of the cardiovascular system, but this molecule has a range of actions that could give it considerable modulatory power.
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Affiliation(s)
- C Robin Hiley
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK.
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67
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Bari M, Spagnuolo P, Fezza F, Oddi S, Pasquariello N, Finazzi-Agrò A, Maccarrone M. Effect of lipid rafts on Cb2 receptor signaling and 2-arachidonoyl-glycerol metabolism in human immune cells. THE JOURNAL OF IMMUNOLOGY 2007; 177:4971-80. [PMID: 17015679 DOI: 10.4049/jimmunol.177.8.4971] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recently, we have shown that treatment of rat C6 glioma cells with the raft disruptor methyl-beta-cyclodextrin (MCD) doubles the binding of anandamide (AEA) to type-1 cannabinoid receptors (CB1R), followed by CB1R-dependent signaling via adenylate cyclase and p42/p44 MAPK activity. In the present study, we investigated whether type-2 cannabinoid receptors (CB2R), widely expressed in immune cells, also are modulated by MCD. We show that treatment of human DAUDI leukemia cells with MCD does not affect AEA binding to CB2R, and that receptor activation triggers similar [35S]guanosine-5'-O-(3-thiotriphosphate) binding in MCD-treated and control cells, similar adenylate cyclase and MAPK activity, and similar MAPK-dependent protection against apoptosis. The other AEA-binding receptor transient receptor potential channel vanilloid receptor subunit 1, the AEA synthetase N-acyl-phosphatidylethanolamine-phospholipase D, and the AEA hydrolase fatty acid amide hydrolase were not affected by MCD, whereas the AEA membrane transporter was inhibited (approximately 55%) compared with controls. Furthermore, neither diacylglycerol lipase nor monoacylglycerol lipase, which respectively synthesize and degrade 2-arachidonoylglycerol, were affected by MCD in DAUDI or C6 cells, whereas the transport of 2-arachidonoylglycerol was reduced to approximately 50%. Instead, membrane cholesterol enrichment almost doubled the uptake of AEA and 2-arachidonoylglycerol in both cell types. Finally, transfection experiments with human U937 immune cells, and the use of primary cells expressing CB1R or CB2R, ruled out that the cellular environment could account per se for the different modulation of CB receptor subtypes by MCD. In conclusion, the present data demonstrate that lipid rafts control CB1R, but not CB2R, and endocannabinoid transport in immune and neuronal cells.
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Affiliation(s)
- Monica Bari
- Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Rome, Italy
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Romano MR, Lograno MD. Cannabinoid agonists induce relaxation in the bovine ophthalmic artery: evidences for CB1 receptors, nitric oxide and potassium channels. Br J Pharmacol 2007; 147:917-25. [PMID: 16474412 PMCID: PMC1760716 DOI: 10.1038/sj.bjp.0706687] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Glaucoma pathophysiology appears to involve vascular deficits, which may contribute to initiation and progression of the disease. Anandamide, the endogenous cannabinoid ligand, and WIN55212-2, a synthetic cannabinoid agonist, are able to evoke concentration-dependent relaxations in bovine ophthalmic artery rings, precontracted with 5-hydroxytryptamine (5-HT) (1 microM). Endothelium removal reduces cannabinoid agonist potency and efficacy. The selective cannabinoid 1 (CB1) receptor antagonists SR141716A (100 nM) and AM251 (100 nM) cause a shift to the right in the concentration-response curves to anandamide and WIN55212-2 in arterial rings both in the presence and in the absence of endothelium. In endothelium-intact arteries, the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA, 300 microM), completely blocked the anandamide- and WIN55212-2-relaxant responses; by contrast, the nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP, 100 microM) induced an increase in vasorelaxant responses to cannabinoid agonists. Relaxations to anandamide and WIN55212-2 were inhibited by iberiotoxin (IbTX, 200 nM), a blocker of large conductance, Ca2+-activated K+ channel (BK(Ca)), and by 4-aminopyridine (4-AP; 1 mM), a blocker of delayed rectifier K+ channel, whereas the blockade of K(ATP) channels by glibenclamide (5 microM) and of small conductance Ca2+-activated K+ channels (SK(Ca)) by apamin (100 nM) did not produce any effects. These data suggest that anandamide and WIN55212-2 relax the bovine ophthalmic artery by involving CB1 the cannabinoid receptor-sensitive pathway. In endothelium-intact arteries, relaxation occurs through activation of nitric oxide synthase cyclic GMP and Ca2+-activated K+ channels. They also cause endothelium-independent relaxation by involving potassium channel opening.
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Affiliation(s)
- Maria Rosaria Romano
- Department of Pharmacobiology, Section of Pharmacology, University of Bari, Via Orabona 4, 70125 Bari, Italy
| | - Marcello D Lograno
- Department of Pharmacobiology, Section of Pharmacology, University of Bari, Via Orabona 4, 70125 Bari, Italy
- Author for correspondence:
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Lee MG, Weinreich D, Undem BJ. Effect of olvanil and anandamide on vagal C-fiber subtypes in guinea pig lung. Br J Pharmacol 2006; 146:596-603. [PMID: 16056239 PMCID: PMC1751189 DOI: 10.1038/sj.bjp.0706339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Certain fatty acid amides such as anandamide (AEA) and olvanil are agonists for the transient receptor potential, vanilloid-1 (TRPV1) receptor, but have been found to activate TRPV1-containing C-fibers in some tissues but not others. We used extracellular recording and whole-cell patch clamp techniques to investigate the effect of olvanil and AEA on different types of vagal C-fibers innervating the same tissue, namely jugular and nodose vagal C-fibers in guinea pig lungs. A 30 s exposure to AEA and olvanil caused action potential discharge in all nodose C-fiber innervating lung but failed to activate jugular C-fibers innervating lung and airways. The activation of nodose C-fibers was blocked by the TRPV1 antagonist iodo-resiniferatoxin. In whole-cell patch clamp recordings of dissociated nodose and jugular capsaicin-sensitive neurons labeled from lungs and airways, olvanil induced large TRPV1-dependent inward currents in cell bodies of both nodose and jugular ganglion neurons. Prolonged exposure (up to 5 min) to olvanil caused action potential discharge in jugular C-fiber innervating lung but the onset latency was four times longer in jugular than in nodose C-fibers. The onsets of capsaicin response in nodose and jugular C-fibers were not different. Decreasing the tissue temperature to 25 degrees C increased the onset latency of olvanil-induced activation of nodose C-fibers 2-3-fold, but did not effect the latency of the capsaicin response. Capsaicin, olvanil, and AEA stimulate jugular C-fibers leading to tachykinergic contractions of isolated bronchi. The time to reach half-maximum is more than four times longer for olvanil and AEA, as compared to capsaicin in evoking contractions. We conclude that brief exposure to certain fatty acid amides, such as AEA and olvanil activate nodose but not jugular C-fiber terminals in the lungs. We hypothesize that this is because the nodose C-fiber terminals are equipped with a temperature-dependent mechanism for effectively and rapidly transporting the TRPV1 agonists so that they gain access to the intracellular binding sites on TRPV1. This transport mechanism may be differently expressed in two distinct subtypes of pulmonary C-fiber terminals innervating the same tissue.
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Affiliation(s)
- Min-Goo Lee
- Johns Hopkins University School of Medicine, Baltimore, MD, U.S.A
| | | | - Bradley J Undem
- Johns Hopkins University School of Medicine, Baltimore, MD, U.S.A
- Author for correspondence:
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70
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Pacher P, Bátkai S, Kunos G. The endocannabinoid system as an emerging target of pharmacotherapy. Pharmacol Rev 2006; 58:389-462. [PMID: 16968947 PMCID: PMC2241751 DOI: 10.1124/pr.58.3.2] [Citation(s) in RCA: 1458] [Impact Index Per Article: 81.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The recent identification of cannabinoid receptors and their endogenous lipid ligands has triggered an exponential growth of studies exploring the endocannabinoid system and its regulatory functions in health and disease. Such studies have been greatly facilitated by the introduction of selective cannabinoid receptor antagonists and inhibitors of endocannabinoid metabolism and transport, as well as mice deficient in cannabinoid receptors or the endocannabinoid-degrading enzyme fatty acid amidohydrolase. In the past decade, the endocannabinoid system has been implicated in a growing number of physiological functions, both in the central and peripheral nervous systems and in peripheral organs. More importantly, modulating the activity of the endocannabinoid system turned out to hold therapeutic promise in a wide range of disparate diseases and pathological conditions, ranging from mood and anxiety disorders, movement disorders such as Parkinson's and Huntington's disease, neuropathic pain, multiple sclerosis and spinal cord injury, to cancer, atherosclerosis, myocardial infarction, stroke, hypertension, glaucoma, obesity/metabolic syndrome, and osteoporosis, to name just a few. An impediment to the development of cannabinoid medications has been the socially unacceptable psychoactive properties of plant-derived or synthetic agonists, mediated by CB(1) receptors. However, this problem does not arise when the therapeutic aim is achieved by treatment with a CB(1) receptor antagonist, such as in obesity, and may also be absent when the action of endocannabinoids is enhanced indirectly through blocking their metabolism or transport. The use of selective CB(2) receptor agonists, which lack psychoactive properties, could represent another promising avenue for certain conditions. The abuse potential of plant-derived cannabinoids may also be limited through the use of preparations with controlled composition and the careful selection of dose and route of administration. The growing number of preclinical studies and clinical trials with compounds that modulate the endocannabinoid system will probably result in novel therapeutic approaches in a number of diseases for which current treatments do not fully address the patients' need. Here, we provide a comprehensive overview on the current state of knowledge of the endocannabinoid system as a target of pharmacotherapy.
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Affiliation(s)
- Pál Pacher
- Laboratory of Physiological Studies, National Institute of Alcohol Abuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane, Room 2S-24, Bethesda, MD 20892-9413, USA
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71
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Howlett AC, Mukhopadhyay S, Norford DC. Endocannabinoids and reactive nitrogen and oxygen species in neuropathologies. J Neuroimmune Pharmacol 2006; 1:305-16. [PMID: 18040807 DOI: 10.1007/s11481-006-9022-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Accepted: 05/16/2006] [Indexed: 01/25/2023]
Abstract
Neuropathologies that affect our population include ischemic stroke and neurodegenerative diseases of immune origin, including multiple sclerosis. The endocannabinoid system in the brain, including agonists anandamide (arachidonyl ethanolamide) and 2-arachidonoylglycerol, and the CB1 and CB2 cannabinoid receptors, has been implicated in the pathophysiology of these disease states, and can be a target for therapeutic interventions. This review concentrates on cellular signal transduction pathways believed to be involved in the cellular damage.
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Affiliation(s)
- Allyn C Howlett
- Neuroscience of Drug Abuse Research Program, 208 Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, 700 George Street, Durham, NC 27707, USA.
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72
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Abstract
The endocannabinoids are endogenous agonists of the cannabinoid receptors and some members of the transient receptor potential, vanilloid type (TRPV), family of cation channels. Endocannabinoids along with their target receptors comprise a signaling system that is not well characterized. There have been many advances in our collective understanding of endocannabinoid signaling in the last decade and experimental evidence is mounting that pharmacological augmentation of endocannabinoid tone might have a significant therapeutic benefit in several disease states. However, the mechanisms responsible for the biosynthesis, cellular uptake, and intracellular processing of endocannabinoids are not well understood and have been the source of much debate. Recent studies have revealed a role for detergent insoluble membrane domains called lipid rafts in various aspects of signaling associated with the endocannabinoid anandamide. Intact detergent insoluble membrane domains appear to play a role in an anandamide-induced signaling cascade that is independent of G protein-coupled cannabinoid receptors or TRPV channels. Furthermore, detergent insoluble membrane domain-related endocytosis and recycling to lipid rafts appear to regulate the organization and localization of anandamide metabolites. We will discuss the implications that these findings have on the way we view endocannabinoid signaling, trafficking, and processing.
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Abstract
The cannabinoid receptor family currently includes two types: CB1, characterized in neuronal cells and brain, and CB2, characterized in immune cells and tissues. CB1 and CB2 receptors are members of the superfamily of seven-transmembrane-spanning (7-TM) receptors, having a protein structure defined by an array of seven membrane-spanning helices with intervening intracellular loops and a C-terminal domain that can associate with G proteins. Cannabinoid receptors are associated with G proteins of the Gi/o family (Gi1, 2 and 3, and Go1 and 2). Signal transduction via Gi inhibits adenylyl cyclase in most tissues and cells, although signaling via Gs stimulates adenylyl cyclase in some experimental models. Evidence exists for cannabinoid receptor-mediated Ca2+ fluxes and stimulation of phospholipases A and C. Stimulation of CB1 and CB2 cannabinoid receptors leads to phosphorylation and activation of p42/p44 mitogen-activated protein kinase (MAPK), p38 MAPK and Jun N-terminal kinase (JNK) as signaling pathways to regulate nuclear transcription factors. The CB1 receptor regulates K+ and Ca2+ ion channels, probably via Go. Ion channel regulation serves as an important component of neurotransmission modulation by endogenous cannabinoid compounds released in response to neuronal depolarization. Cannabinoid receptor signaling via G proteins results from interactions with the second, third and fourth intracellular loops of the receptor. Desensitization of signal transduction pathways that couple through the G proteins probably entails phosphorylation of critical amino acid residues on these intracellular surfaces.
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Affiliation(s)
- A C Howlett
- Neuroscience/Drug Abuse Research Program, 208 JLC-BBRI, North Carolina Central University, 700 George Street, Durham, NC 27707, USA.
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75
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Bojesen IN, Hansen HS. Effect of an unstirred layer on the membrane permeability of anandamide. J Lipid Res 2005; 47:561-70. [PMID: 16365480 DOI: 10.1194/jlr.m500411-jlr200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To study the effect of an unstirred layer (UL), we have investigated the exchange efflux kinetics of anandamide at 0 degrees C, pH 7.3, from albumin-free as well as from albumin-filled human red blood cell ghosts to media of various BSA concentrations ([BSA](o)). The rate constant (k(m)) of unidirectional flux from the outer membrane leaflet to BSA in the medium increased with the square root of [BSA](o) in accordance with the existence of a UL, which is a water layer adjacent to the membrane that is not subject to the same gross mixing that takes place in the rest of the medium. From k(m), it is possible to calculate the rate constant of anandamide dissociation from BSA (k(1)) if we know the membrane binding of anandamide, the equilibrium dissociation constant of BSA-anandamide complexes, and the diffusion constant of anandamide. We estimated k(1) to be 3.33 +/- 0.27 s(-1). The net flux of [(3)H]anandamide is balanced by an equal and opposite movement of nonradioactive anandamide in exchange efflux experiments. This means that our results are also valid for uptake. We show that for anandamide with rapid membrane translocation, UL causes a significant resistance to cellular uptake. Depicting the rate of anandamide uptake as a function of equilibrium water phase concentrations results in a parabolic uptake dependence. Such apparent "saturation kinetics" is often interpreted as indicating the involvement of transport proteins. The validity of such an interpretation is discussed.
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Affiliation(s)
- Inge N Bojesen
- Department of Medical Biochemistry and Genetics, Laboratory B, University of Copenhagen, Panum Institute, DK-2200 Copenhagen N, Denmark.
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76
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Moore SA, Nomikos GG, Dickason-Chesterfield AK, Schober DA, Schaus JM, Ying BP, Xu YC, Phebus L, Simmons RMA, Li D, Iyengar S, Felder CC. Identification of a high-affinity binding site involved in the transport of endocannabinoids. Proc Natl Acad Sci U S A 2005; 102:17852-7. [PMID: 16314570 PMCID: PMC1295594 DOI: 10.1073/pnas.0507470102] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phytocannabinoids, such as the principal bioactive component of marijuana, delta9-tetrahydrocannabinol, have been used for thousands of years for medical and recreational purposes. delta9-Tetrahydrocannabinol and endogenous cannabinoids (e.g., anandamide) initiate their agonist properties by stimulating the cannabinoid family of G protein-coupled receptors (CB1 and CB2). The biosynthesis and physiology of anandamide is well understood, but its mechanism of uptake (resulting in signal termination by fatty acid amide hydrolase) has been elusive. Mounting evidence points to the existence of a specific anandamide transport protein; however, no direct evidence for this protein has been provided. Here, we use a potent, competitive small molecule inhibitor of anandamide uptake (LY2318912, IC50 7.27 +/- 0.510 nM) to identify a high-affinity, saturable anandamide transporter binding site (LY2318912; K(d) = 7.62 +/- 1.18 nM, B(max) = 31.6 +/- 1.80 fmol/mg protein) that is distinct from fatty acid amide hydrolase. Systemic administration of the inhibitor into rodents elevates anandamide levels 5-fold in the brain and demonstrates efficacy in the formalin paw-licking model of persistent pain with no obvious adverse effects on motor function. Identification of the anandamide transporter binding site resolves a missing mechanistic link in endocannabinoid signaling, and in vivo results suggest that endocannabinoid transporter antagonists may provide a strategy for positive modulation of cannabinoid receptors.
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Affiliation(s)
- S A Moore
- Eli Lilly and Company, Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN 46285-0510, USA
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77
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Chen P, Hu S, Yao J, Moore SA, Spector AA, Fang X. Induction of cyclooxygenase-2 by anandamide in cerebral microvascular endothelium. Microvasc Res 2005; 69:28-35. [PMID: 15797258 DOI: 10.1016/j.mvr.2005.02.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Indexed: 02/03/2023]
Abstract
Anandamide (AEA), an endogenous cannabinoid receptor agonist, is a potent vasodilator in the cerebral microcirculation. AEA is converted to arachidonic acid (AA) by fatty acid amidohydrolase (FAAH), and the conversion of AA to prostaglandins has been proposed as a potential mechanism for the vasodilation. Although AEA stimulated prostaglandin production by mouse cerebral microvascular endothelial cells, no [(3)H]prostaglandins were produced when these cells were incubated with [3H]AEA. Incubation with R(+)-methanandamide (MAEA), a stable analogue of AEA that is not a substrate for FAAH, produced a similar increase in PGE2 production as AEA. The PGE2 production induced by either AEA or MAEA was completely inhibited by NS-398, a selective cyclooxygenase (COX)-2 inhibitor, suggesting that COX-2 was induced. AEA and MAEA increased the expression of COX-2 protein in a time-dependent manner. This increase occurred as early as 1 h and reached maximum at 2 h. Induction of COX-2 protein by AEA was partially inhibited by AM-251, a selective cannabinoid receptor-1 antagonist. Furthermore, AEA increased COX-2 promoter activity approximately twofold above baseline in a fragment ranging from -1432 to +59, the full-length of the COX-2 promoter, and the increase in COX-2 promoter activity produced by AEA was partially inhibited by AM-251. These results indicate that AEA increased COX-2 expression at the transcriptional level through, at least in part, a cannabinoid receptor-1-mediated mechanism in cerebral microvascular endothelium.
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Affiliation(s)
- Ping Chen
- Department of Biochemistry, 4-403 BSB, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
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78
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Poblete IM, Orliac ML, Briones R, Adler-Graschinsky E, Huidobro-Toro JP. Anandamide elicits an acute release of nitric oxide through endothelial TRPV1 receptor activation in the rat arterial mesenteric bed. J Physiol 2005; 568:539-51. [PMID: 16081483 PMCID: PMC1474725 DOI: 10.1113/jphysiol.2005.094292] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
In the isolated rat mesenteric bed, the 1 min perfusion with 100 nm anandamide, a concentration that did not evoke vasorelaxation, elicited an acute release of 165.1 +/- 9.2 pmol nitric oxide (NO) that was paralleled by a 2-fold increase in cGMP tissue levels. The rise in NO released was mimicked by either (R)-(+)-methanandamide or the vanilloid receptor agonists resiniferatoxin and (E)-capsaicin but not by its inactive cis-isomer (Z)-capsaicin. The NO release elicited by either anandamide or capsaicin was reduced by the TRPV1 receptor antagonists 5'-iodoresiniferatoxin, SB 366791 and capsazepine as well as by the cannabinoid CB(1) receptor antagonists SR 141716A or AM251. The outflow of NO elicited by anandamide and capsaicin was also reduced by endothelium removal or NO synthase inhibition, suggesting the specific participation of endothelial TRPV1 receptors, rather than the novel endothelial TRPV4 receptors. Consistently, RT-PCR showed the expression of the mRNA coding for the rat TRPV1 receptor in the endothelial cell layer, in addition to its expression in sensory nerves. The participation of sensory nerves on the release of NO was precluded on the basis that neonatal denervation of the myenteric plexus sensory nerves did not modify the pattern of NO release induced by anandamide and capsaicin. We propose that low concentrations of anandamide, devoid of vasorelaxing effects, elicit an acute release of NO mediated predominantly by the activation of endothelial TRPV1 receptors whose physiological significance remains elusive.
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Affiliation(s)
- Inés M Poblete
- Centro de Regulación Celular y Patología JV Luco, Instituto MIFAB, Departmento de Fisiología, Facultad de Ciencias Biológicas, P. Universidad Católica de Chile, Santiago
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79
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De Petrocellis L, Di Marzo V. Lipids as regulators of the activity of transient receptor potential type V1 (TRPV1) channels. Life Sci 2005; 77:1651-66. [PMID: 15936040 DOI: 10.1016/j.lfs.2005.05.021] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
After 7 years from its cloning, the transient receptor potential vanilloid type-1 (TRPV1) channel remains the sole membrane receptor mediating the pharmacological effects of the hot chilli pepper pungent component, capsaicin, and of the Euphorbia toxin, resiniferatoxin. Yet, this ion channel represents one of the most complex examples of how the activity of a protein can be regulated. Among the several chemicophysical stimuli that can modulate TRPV1 permeability to cations, endogenous lipids appear to play a major role, either as allosteric effectors or as direct agonists, or both. Furthermore, the capability of some mediators, such as the endocannabinoid anandamide, or the eicosanoid precursors 12- and 5-hydroperoxy-eicosatetraenoic acids, to activate TRPV1 receptors provides a striking example of the "site-dependent" and "metabolic" functional plasticity, respectively, typical of bioactive lipids. In this article, the multi-faceted and most recently discovered aspects of TRPV1 regulation are reviewed, with particular emphasis on the interaction between these membrane channels and some lipid molecules.
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Affiliation(s)
- Luciano De Petrocellis
- Endocannabinoid Research Group, Istituto di Cibernetica Eduardo Caianiello, Consiglio Nazionale delle Ricerche, Via Campi Flegrei 34, Comprensorio Olivetti, Fabbricato 70, 80078 Pozzuoli, Napoli, Italy
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80
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Di Marzo V, De Petrocellis L, Bisogno T. Endocannabinoids Part I: molecular basis of endocannabinoid formation, action and inactivation and development of selective inhibitors. Expert Opin Ther Targets 2005; 5:241-65. [PMID: 15992179 DOI: 10.1517/14728222.5.2.241] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The discovery of specific receptors for Delta9-tetrahydrocannabinol, the major psychoactive component of marijuana, opened new horizons for the possible therapeutic exploitation of Cannabis sativa and the cannabinoids. Endogenous ligands of cannabinoid receptors, the 'endocannabinoids', were found and the molecular mechanisms underlying their biological effects and the regulation of their levels are now being identified. Cause/effect relationships between alterations of cannabinoid receptor/endocannabinoid levels in tissues and the symptoms of various pathological states are starting to be revealed. These studies may open the way to the possible use of substances that manipulate endocannabinoid levels and actions, such as inhibitors of the biosynthesis and inactivation and receptor antagonists, as cannabinoid-based therapeutic agents with little or no psychotropic side effect, thus potentially fulfilling an ambition nurtured for almost two centuries.
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Affiliation(s)
- V Di Marzo
- Istituto per la Chimica di Molecole di Interesse Biologico, Consiglio Nazionale delle Ricerche, Via Toiano 6, 80072, Arco Felice (NA), Italy.
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81
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Sterin-Borda L, Del Zar CF, Borda E. Differential CB1 and CB2 cannabinoid receptor-inotropic response of rat isolated atria: Endogenous signal transduction pathways. Biochem Pharmacol 2005; 69:1705-13. [DOI: 10.1016/j.bcp.2005.03.027] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Revised: 03/11/2005] [Accepted: 03/11/2005] [Indexed: 11/28/2022]
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82
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Chen P, Hu S, Harmon SD, Moore SA, Spector AA, Fang X. Metabolism of anandamide in cerebral microvascular endothelial cells. Prostaglandins Other Lipid Mediat 2005; 73:59-72. [PMID: 15165032 DOI: 10.1016/j.prostaglandins.2003.11.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Anandamide (N-arachidonoylethanolamine, AEA), an endogenous cannabinoid receptor agonist, causes potent vasodilation in the cerebral circulation through an endothelial-dependent or -independent mechanism. We have investigated the processing of [3H]AEA in cultured mouse cerebral microvascular endothelial cells (MEC) in order to better understand its mechanism of action in the cerebral vasculature. These cells took up anandamide very quickly, reaching a maximum value in 5 min and remaining at that level for at least 8 h. Analysis of the cell lipids demonstrated that, in addition to free anandamide, radioactivity was incorporated into phosphatidylcholine (PC), phosphatidylinositol (PI), and phosphatidylethanolamine (PE) in a time-dependent manner. Analysis of the hydrolyzed cell lipids indicated that anandamide was converted to arachidonic acid, a process that was inhibited by the selective fatty acid amide hydrolase inhibitor oleyl trifluoromethyl ketone (OTMK). Phospholipase A2 (PLA2) hydrolysis of the PC, PI, and PE fractions indicated that the arachidonic acid formed from anandamide was esterified predominately into sn-2 position of the endothelial phospholipids. Furthermore, anandamide and arachidonic acid were released when the cells were incubated with A23187. These results suggest that the biological activity of anandamide might be regulated by its rapid uptake and calcium-dependent release in endothelial cells, and conversion of anandamide to arachidonic acid might serve as an inactivation process in the cerebral microcirculation.
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Affiliation(s)
- Ping Chen
- Department of Biochemistry, University of Iowa College of Medicine, 4-403 BSB, Iowa City, IA 52242, USA
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83
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Bari M, Battista N, Fezza F, Finazzi-Agrò A, Maccarrone M. Lipid rafts control signaling of type-1 cannabinoid receptors in neuronal cells. Implications for anandamide-induced apoptosis. J Biol Chem 2005; 280:12212-20. [PMID: 15657045 DOI: 10.1074/jbc.m411642200] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Several G protein-coupled receptors function within lipid rafts plasma membrane microdomains, which may be important in limiting signal transduction. Here we show that treatment of rat C6 glioma cells with the raft disruptor methyl-beta-cyclodextrin (MCD) doubles the binding efficiency (i.e. the ratio between maximum binding and dissociation constant) of type-1 cannabinoid receptors (CB1R), which belong to the rhodopsin family of G protein-coupled receptors. In parallel, activation of CB1R by the endogenous agonist anandamide (AEA) leads to approximately 3-fold higher [35S]GTPgammaS binding in MCD-treated cells than in controls, and CB1R-dependent signaling via adenylate cyclase, and p42/p44 MAPK is almost doubled by MCD. Unlike CB1R, the other AEA-binding receptor TRPV1, the AEA synthetase NAPE-PLD, and the AEA hydrolase FAAH are not modulated by MCD, whereas the activity of the AEA membrane transporter (AMT) is reduced to approximately 50% of the controls. We also show that MCD reduces dose-dependently AEA-induced apoptosis in C6 cells but not in human CHP100 neuroblastoma cells, which mirror the endocannabinoid system of C6 cells but are devoid of CB1R. MCD reduces also cytochrome c release from mitochondria of C6 cells, and this effect is CB1R-dependent and partly mediated by activation of p42/p44 MAPK. Altogether, the present data suggest that lipid rafts control CB1R binding and signaling, and that CB1R activation underlies the protective effect of MCD against apoptosis.
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Affiliation(s)
- Monica Bari
- Department of Biomedical Sciences, University of Teramo, 64100 Teramo, Italy
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84
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Bari M, Paradisi A, Pasquariello N, Maccarrone M. Cholesterol-dependent modulation of type 1 cannabinoid receptors in nerve cells. J Neurosci Res 2005; 81:275-83. [PMID: 15920744 DOI: 10.1002/jnr.20546] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Type 1 cannabinoid receptors (CB1R) are G-protein-coupled receptors that mediate several actions of the endocannabinoid anandamide (N-arachidonoylethanolamine; AEA) in the central nervous system. Here we show that cholesterol enrichment of rat C6 glioma cell membranes reduces by approximately twofold the binding efficiency (i.e., the ratio between maximum binding and dissociation constant) of CB1R and that activation of CB1R by AEA leads to approximately twofold lower [(35)S]GTPgammaS binding in cholesterol-treated cells than in controls. In addition, we show that CB1R-dependent signaling via adenylate cyclase and p42/p44 mitogen-activated protein kinase is almost halved by cholesterol enrichment. Unlike CB1R, the other AEA-binding receptor TRPV1, the AEA synthetase NAPE-PLD, and the AEA hydrolase FAAH are not modulated by cholesterol, whereas the catalytic efficiency (i.e., the ratio between maximal velocity and Michaelis-Menten constant) of the AEA membrane transporter AMT is almost doubled compared with control cells. These data demonstrate that, among the proteins of the "endocannabinoid system," only CB1R and AMT critically depend on membrane cholesterol content. This observation may have important implications for the role of CB1R in protecting nerve cells against (endo)cannabinoid-induced apoptosis.
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Affiliation(s)
- Monica Bari
- Department of Biomedical Sciences, University of Teramo, Teramo, Italy
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85
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Di Marzo V, De Petrocellis L, Bisogno T. The biosynthesis, fate and pharmacological properties of endocannabinoids. Handb Exp Pharmacol 2005:147-85. [PMID: 16596774 DOI: 10.1007/3-540-26573-2_5] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The finding of endogenous ligands for cannabinoid receptors, the endocannabinoids, opened a new era in cannabinoid research. It meant that the biological role of cannabinoid signalling could be finally studied by investigating not only the pharmacological actions subsequent to stimulation of cannabinoid receptors by their agonists, but also how the activity of these receptors was regulated under physiological and pathological conditions by varying levels of the endocannabinoids. This in turn meant that the enzymes catalysing endocannabinoid biosynthesis and inactivation had to be identified and characterized, and that selective inhibitors of these enzymes had to be developed to be used as (1) probes to confirm endocannabinoid involvement in health and disease, and (2) templates for the design of new therapeutic drugs. This chapter summarizes the progress achieved in this direction during the 12 years following the discovery of the first endocannabinoid.
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Affiliation(s)
- V Di Marzo
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Via Campi Flegrei 34, Comprensorio Olivetti, Fabbricato 70, 80078 Pozzuoli (Napoli), Italy.
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86
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Abstract
Cannabinoids and their synthetic and endogenous analogs affect a broad range of physiological functions, including cardiovascular variables, the most important component of their effect being profound hypotension. The mechanisms of the cardiovascular effects of cannabinoids in vivo are complex and may involve modulation of autonomic outflow in both the central and peripheral nervous systems as well as direct effects on the myocardium and vasculature. Although several lines of evidence indicate that the cardiovascular depressive effects of cannabinoids are mediated by peripherally localized CB1 receptors, recent studies provide strong support for the existence of as-yet-undefined endothelial and cardiac receptor(s) that mediate certain endocannabinoid-induced cardiovascular effects. The endogenous cannabinoid system has been recently implicated in the mechanism of hypotension associated with hemorrhagic, endotoxic, and cardiogenic shock, and advanced liver cirrhosis. Furthermore, cannabinoids have been considered as novel antihypertensive agents. A protective role of endocannabinoids in myocardial ischemia has also been documented. In this chapter, we summarize current information on the cardiovascular effects of cannabinoids and highlight the importance of these effects in a variety of pathophysiological conditions.
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Affiliation(s)
- P Pacher
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892-9413, USA.
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87
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Battista N, Gasperi V, Fezza F, Maccarrone M. The anandamide membrane transporter and the therapeutic implications of its inhibition. ACTA ACUST UNITED AC 2005. [DOI: 10.2217/14750708.2.1.141] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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88
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Hinz B, Ramer R, Eichele K, Weinzierl U, Brune K. R(+)-methanandamide-induced cyclooxygenase-2 expression in H4 human neuroglioma cells: possible involvement of membrane lipid rafts. Biochem Biophys Res Commun 2004; 324:621-6. [PMID: 15474472 DOI: 10.1016/j.bbrc.2004.09.095] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Indexed: 11/20/2022]
Abstract
Cannabinoids induce the expression of the cyclooxygenase-2 (COX-2) isoenzyme in H4 human neuroglioma cells via a pathway independent of cannabinoid- or vanilloid receptor activation. The underlying mechanism was recently shown to involve increased synthesis of ceramide, which in turn leads to activation of p38 and p42/44 mitogen-activated protein kinases (MAPKs). The present study investigates a possible contribution of membrane lipid rafts to cannabinoid-induced COX-2 expression. To address this issue, we tested the influence of methyl-beta-cyclodextrin (MCD), a membrane cholesterol depletor, on COX-2 expression by the endocannabinoid analogue R(+)-methanandamide (R(+)-MA). Incubation of H4 cells with MCD was associated with a loss of lipid raft integrity and a substantial inhibition of R(+)-MA-induced COX-2 expression and subsequent formation of prostaglandin E2. Moreover, MCD was shown to suppress signal transduction steps upstream to COX-2 induction by R(+)-MA. Accordingly, the cholesterol depletor suppressed R(+)-MA-induced formation of ceramide as well as phosphorylation of p38 and p42/44 MAPKs. Together, our results suggest that R(+)-MA induces COX-2 expression in human neuroglioma cells via a pathway linked to lipid raft microdomains.
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Affiliation(s)
- Burkhard Hinz
- Department of Experimental and Clinical Pharmacology and Toxicology, Friedrich Alexander University Erlangen-Nürnberg, Fahrstrasse 17, D-91054 Erlangen, Germany.
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89
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Ligresti A, Morera E, Van Der Stelt M, Monory K, Lutz B, Ortar G, Di Marzo V. Further evidence for the existence of a specific process for the membrane transport of anandamide. Biochem J 2004; 380:265-72. [PMID: 14969584 PMCID: PMC1224156 DOI: 10.1042/bj20031812] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2003] [Revised: 01/26/2004] [Accepted: 02/17/2004] [Indexed: 12/29/2022]
Abstract
Indirect evidence for the existence of a specific protein-mediated process for the cellular uptake of endocannabinoids has been reported, but recent results suggested that such a process, at least for AEA [ N -arachidonoylethanolamine (anandamide)], is facilitated uniquely by its intracellular hydrolysis by FAAH (fatty acid amide hydrolase) [Glaser, Abumrad, Fatade, Kaczocha, Studholme and Deutsch (2003) Proc. Natl. Acad. Sci. U.S.A. 100, 4269-4274]. In the present study, we show that FAAH alone cannot account for the facilitated diffusion of AEA across the cell membrane. In particular, (i) using a short incubation time (90 s) to avoid AEA hydrolysis by FAAH, AEA accumulation into rat basophilic leukaemia or C6 cells was saturable at low microM concentrations of substrate and non-saturable at higher concentrations; (ii) time-dependent and, at low microM concentrations of substrate, saturable AEA accumulation was observed also using mouse brain synaptosomes; (iii) using synaptosomes prepared from FAAH-deficient mice, saturable AEA accumulation was still observed, although with a lower efficacy; (iv) when 36 AEA and N -oleoylethanolamine analogues, most of which with phenyl rings in the polar head group region, were tested as inhibitors of AEA cellular uptake, strict structural and stereochemical requirements were needed to observe significant inhibition, and in no case the inhibition of FAAH overlapped with the inhibition of AEA uptake; and (v) AEA biosynthesis by cells and sensory neurons was followed by AEA release, and this latter process, which cannot be facilitated by FAAH, was still blocked by an inhibitor of AEA uptake. We suggest that at least one protein different from FAAH is required to facilitate AEA transport across the plasma membrane in a selective and bi-directional way.
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Affiliation(s)
- Alessia Ligresti
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Via Campi Flegrei 34, Comprensorio Olivetti, Bldg. 70, 80078 Pozzuoli (NA), Italy
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90
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Moezi L, Rezayat M, Samini M, Shafaroodi H, Mehr SE, Ebrahimkhani MR, Dehpour AR. Potentiation of anandamide effects in mesenteric beds isolated from bile duct-ligated rats: role of nitric oxide. Eur J Pharmacol 2004; 486:53-9. [PMID: 14751408 DOI: 10.1016/j.ejphar.2003.12.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Changes in vascular responsiveness are proposed as the basis for some of the cardiovascular complications in cholestasis. Cholestasis is also associated with accumulation of endogenous opioid peptides and evidence of nitric oxide (NO) overproduction. On the other hand, it is well known that anandamide, an endogenous cannabinoid ligand, causes hypotension and a decrease in systemic vascular resistance. In the present study, the possible role of the cannabinoid system in cholestasis-induced mesenteric vascular bed responsiveness was investigated. Mesenteric arteries of bile duct-ligated and sham-operated rats receiving daily administrations of saline were used for evaluating phenylephrine or anandamide dose-response, acute effects of N(G)-nitro-L-arginine methyl ester (L-NAME, 100 microM), a non-selective inhibitor of NO synthase (NOS), or naltrexone, an opioid receptors antagonist (1 microM). The other groups of bile duct-ligated and sham-operated rats received daily intraperitoneal administration of L-NAME (20 mg/kg/day), aminoguanidine, a selective inducible NOS (iNOS) inhibitor (150 mg/kg/day) or naltrexone (10 mg/kg/day). After 7 days, the superior mesenteric artery was cannulated and the mesenteric vascular bed was perfused according to the McGregor method. Anandamide-induced relaxation was significantly potentiated in mesenteric vascular beds of bile duct-ligated rats. Chronic treatment of bile duct-ligated animals with L-NAME and aminoguanidine blocked this hyperresponsiveness while the hyperresponsiveness was potentiated at large doses of anandamide on chronic treatment of these animals with naltrexone. Although acute L-NAME treatment of mesenteric beds completely blocked the anandamide-induced vasorelaxation in sham-operated rats, this vasorelaxation still was present in bile duct-ligated animals. Anandamide-induced vasorelaxation remained unaffected after acute naltrexone treatment of mesenteric beds in both bile duct-ligated and sham-operated rats. Our results indicate that (1) there is enhanced anandamide-induced vasorelaxation in cholestatic rats, probably due to a defect in cannabinoid or vanilloid receptors and (2) NO overproduction may be involved in cholestasis-induced vascular hyperresponsiveness.
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Affiliation(s)
- Leila Moezi
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O.Box 13145-784, Tehran, Iran
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91
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Evans RM, Scott RH, Ross RA. Multiple actions of anandamide on neonatal rat cultured sensory neurones. Br J Pharmacol 2004; 141:1223-33. [PMID: 15023857 PMCID: PMC1574891 DOI: 10.1038/sj.bjp.0705723] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. We have investigated the effects of the endocannabinoid anandamide (AEA) on neuronal excitability and vanilloid TRPV1 receptors in neonatal rat cultured dorsal root ganglion neurones. 2. Using whole-cell patch-clamp electrophysiology, we found that AEA inhibits high-voltage-activated Ca(2+) currents by 33+/-9% (five out of eight neurones) in the absence of the CB(1) receptor antagonist SR141716A (100 nM) and by 32+/-6% (seven out of 10 neurones) in the presence of SR141716A. 3. Fura-2 fluorescence Ca(2+) imaging revealed that AEA produced distinct effects on Ca(2+) transients produced by depolarisation evoked by 30 mM KCl. In a population of neurones of larger somal area (372+/-20 microM(2)), it significantly enhanced Ca(2+) transients (80.26+/-13.12% at 1 microM), an effect that persists after pertussis toxin pretreatment. In a population of neurones of smaller somal area (279+/-18 microM(2)), AEA significantly inhibits Ca(2+) transients (30.75+/-3.54% at 1 microM), an effect that is abolished by PTX pretreatment. 4. Extracellular application of 100 nM AEA failed to evoke TRPV1 receptor inward currents in seven out of eight neurones that responded to capsaicin (1 microM), with a mean inward current of -0.94+/-0.21 nA. In contrast, intracellular application of 100 nM AEA elicited robust inward currents in approximately 62% of neurones, the mean population response was -0.85+/-0.21 nA. When AEA was applied to the intracellular environment with capsazepine (1 microM), the mean population inward current was -0.01+/-0.01 nA. Under control conditions, mean population current fluctuations of -0.09+/-0.05 nA were observed.
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MESH Headings
- Animals
- Animals, Newborn
- Arachidonic Acids/pharmacology
- Calcium Channels/drug effects
- Calcium Channels/physiology
- Calcium Signaling/drug effects
- Calcium Signaling/physiology
- Capsaicin/analogs & derivatives
- Capsaicin/pharmacology
- Cells, Cultured
- Drug Synergism
- Endocannabinoids
- Fura-2/chemistry
- Ganglia, Spinal/cytology
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/physiology
- Neurons, Afferent/drug effects
- Pertussis Toxin/pharmacology
- Piperidines/pharmacology
- Polyunsaturated Alkamides
- Potassium Chloride/pharmacology
- Pyrazoles/pharmacology
- Rats
- Receptor, Cannabinoid, CB1/drug effects
- Receptor, Cannabinoid, CB1/physiology
- Receptors, Drug/antagonists & inhibitors
- Receptors, Drug/drug effects
- Rimonabant
- TRPV Cation Channels
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Affiliation(s)
- Rhian M Evans
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland
| | - Roderick H Scott
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland
| | - Ruth A Ross
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland
- Author for correspondence:
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92
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Nilius B, Vriens J, Prenen J, Droogmans G, Voets T. TRPV4 calcium entry channel: a paradigm for gating diversity. Am J Physiol Cell Physiol 2004; 286:C195-205. [PMID: 14707014 DOI: 10.1152/ajpcell.00365.2003] [Citation(s) in RCA: 350] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The vanilloid receptor-1 (VR1, now TRPV1) was the founding member of a subgroup of cation channels within the TRP family. The TRPV subgroup contains six mammalian members, which all function as Ca2+ entry channels gated by a variety of physical and chemical stimuli. TRPV4, which displays 45% sequence identity with TRPV1, is characterized by a surprising gating promiscuity: it is activated by hypotonic cell swelling, heat, synthetic 4alpha-phorbols, and several endogenous substances including arachidonic acid (AA), the endocannabinoids anandamide and 2-AG, and cytochrome P-450 metabolites of AA, such as epoxyeicosatrienoic acids. This review summarizes data on TRPV4 as a paradigm of gating diversity in this subfamily of Ca2+ entry channels.
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Affiliation(s)
- Bernd Nilius
- Laboratorium voor Fysiologie, KU Leuven, Campus Gasthuisberg, 3000 Leuven, Belgium.
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93
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Petrocellis LD, Cascio MG, Marzo VD. The endocannabinoid system: a general view and latest additions. Br J Pharmacol 2004; 141:765-74. [PMID: 14744801 PMCID: PMC1574255 DOI: 10.1038/sj.bjp.0705666] [Citation(s) in RCA: 332] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
After the discovery, in the early 1990s, of specific G-protein-coupled receptors for marijuana's psychoactive principle Delta(9)-tetrahydrocannabinol, the cannabinoid receptors, and of their endogenous agonists, the endocannabinoids, a decade of investigations has greatly enlarged our understanding of this altogether new signalling system. Yet, while the finding of the endocannabinoids resulted in a new effort to reveal the mechanisms regulating their levels in the brain and peripheral organs under physiological and pathological conditions, more endogenous substances with a similar action, and more molecular targets for the previously discovered endogenous ligands, anandamide and 2-arachidonoylglycerol, or for some of their metabolites, were being proposed. As the scenario becomes subsequently more complicated, and the experimental tasks to be accomplished correspondingly more numerous, we briefly review in this article the latest 'additions' to the endocannabinoid system together with earlier breakthroughs that have contributed to our present knowledge of the biochemistry and pharmacology of the endocannabinoids.
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Affiliation(s)
- Luciano De Petrocellis
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Via Campi Flegrei 34, Comprensorio Olivetti, Fabbricato 70, 80078 Pozzuoli (Napoli), Italy
| | - Maria Grazia Cascio
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Via Campi Flegrei 34, Comprensorio Olivetti, Fabbricato 70, 80078 Pozzuoli (Napoli), Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Via Campi Flegrei 34, Comprensorio Olivetti, Fabbricato 70, 80078 Pozzuoli (Napoli), Italy
- Author for correspondence:
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94
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Ruiz-Llorente L, Ortega-Gutiérrez S, Viso A, Sánchez MG, Sánchez AM, Fernández C, Ramos JA, Hillard C, Lasunción MA, López-Rodríguez ML, Díaz-Laviada I. Characterization of an anandamide degradation system in prostate epithelial PC-3 cells: synthesis of new transporter inhibitors as tools for this study. Br J Pharmacol 2004; 141:457-67. [PMID: 14718261 PMCID: PMC1574211 DOI: 10.1038/sj.bjp.0705628] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The response of anandamide is terminated by a carrier-mediated transport followed by degradation catalyzed by the cloned enzyme fatty acid amidohydrolase (FAAH). In this study, we provide biochemical data showing an anandamide uptake process and the expression of FAAH in human prostate. Anandamide was accumulated in PC-3 cells by a saturable and temperature-dependent process. Kinetic studies of anandamide uptake, determined in the presence of cannabinoid and vanilloid antagonists, revealed apparent parameters of KM=4.7+/-0.2 microm and Vmax=3.3+/-0.3 pmol min-1 (10(6) cells)-1. The accumulation of anandamide was moderately inhibited by previously characterized anandamide transporter inhibitors (AM404, UCM707 and VDM11) but was unaffected by inhibitors of other lipid transport systems (phloretin or verapamil) and moderately affected by the FAAH inhibitor methyl arachidonyl fluorophosphonate. The presence of FAAH in human prostate epithelial PC-3 cells was confirmed by analyzing its expression by Western blot and measuring FAAH activity. To further study the structural requirements of the putative carrier, we synthesized a series of structurally different compounds 1-8 and evaluated their capacity as uptake inhibitors. They showed different inhibitory capacity in PC-3 cells, with (9Z,12Z)-N-(fur-3-ylmethyl)octadeca-9,12-dienamide (4, UCM119) being the most efficacious, with maximal inhibition and IC50 values of 49% and 11.3+/-0.5 microM, respectively. In conclusion, PC-3 cells possess a complete inactivation system for anandamide formed by an uptake process and the enzyme FAAH. These results suggest a possible physiological function of anandamide in the prostate, reinforcing the role of endocannabinoid system as a neuroendocrine modulator. British Journal of Pharmacology (2004) 141, 457-467. doi:10.1038/sj.bjp.0705628
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Affiliation(s)
- Lidia Ruiz-Llorente
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain
| | - Silvia Ortega-Gutiérrez
- Departamento de Química Orgánica, Facultad de Químicas, Universidad Complutense, 28040 Madrid, Spain
| | - Alma Viso
- Departamento de Química Orgánica, Facultad de Químicas, Universidad Complutense, 28040 Madrid, Spain
| | - María G Sánchez
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain
| | - Ana M Sánchez
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain
| | - Carlos Fernández
- Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal, 28034 Madrid, Spain
| | - José A Ramos
- Departamento de Bioquímica y Biología Molecular III, Facultad de Medicina, Universidad Complutense, 28040 Madrid, Spain
| | - Cecilia Hillard
- Department of Pharmacology, Medical College of Wisconsin, 8701 Watertown Plank Rd, Milwaukee, WI 53226-0509, U.S.A
| | - Miguel A Lasunción
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain
- Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal, 28034 Madrid, Spain
| | - María L López-Rodríguez
- Departamento de Química Orgánica, Facultad de Químicas, Universidad Complutense, 28040 Madrid, Spain
| | - Inés Díaz-Laviada
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain
- Author for correspondence:
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95
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Manzanares J, Urigüen L, Rubio G, Palomo T. Role of endocannabinoid system in mental diseases. Neurotox Res 2004; 6:213-24. [PMID: 15325960 DOI: 10.1007/bf03033223] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In the last decade, a large number of studies using Delta9-tetrahydrocannabinol (THC), the main active principle derivative of the marijuana plant, or cannabinoid synthetic derivatives have substantially contributed to advance the understanding of the pharmacology and neurobiological mechanisms produced by cannabinoid receptor activation. Cannabis has been historically used to relieve some of the symptoms associated with central nervous system disorders. Nowadays, there are anecdotal evidences for the use of cannabis in many patients suffering from multiple sclerosis or chronic pain. Following the historical reports of the use of cannabis for medicinal purposes, recent research has highlighted the potential of cannabinoids to treat a wide variety of clinical disorders. Some of these disorders that are being investigated are pain, motor dysfunctions or psychiatric illness. On the other hand, cannabis abuse has been related to several psychiatric disorders such as dependence, anxiety, depression, cognitive impairment, and psychosis. Considering that cannabis or cannabinoid pharmaceutical preparations may no longer be exclusively recreational drugs but may also present potential therapeutic uses, it has become of great interest to analyze the neurobiological and behavioral consequences of their administration. This review attempts to link current understanding of the basic neurobiology of the endocannabinoid system to novel opportunities for therapeutic intervention and its effects on the central nervous system.
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Affiliation(s)
- Jorge Manzanares
- Servicio de Psiquiatría y Unidad de Investigación, Hospital 12 de Octubre, Edificio Materno-Infantil, Planta 6a, 613-A, Avenida de Córdoba s/n. 28041 Madrid, Spain.
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96
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de Lago E, Ligresti A, Ortar G, Morera E, Cabranes A, Pryce G, Bifulco M, Baker D, Fernandez-Ruiz J, Di Marzo V. In vivo pharmacological actions of two novel inhibitors of anandamide cellular uptake. Eur J Pharmacol 2004; 484:249-57. [PMID: 14744610 DOI: 10.1016/j.ejphar.2003.11.027] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Two inhibitors of the cellular uptake of the endocannabinoid anandamide, (R)-N-oleoyl-(1'-hydroxybenzyl)-2'-ethanolamine and (S)-N-oleoyl-(1'-hydroxybenzyl)-2'-ethanolamine (OMDM-1 and OMDM-2, respectively), were recently synthesized, and their in vitro pharmacological activity described. Here we have assessed their activity in two typical pharmacological responses of cannabimimetic compounds. We first examined whether these compounds exert any effect per se on locomotion and pain perception in rats, and/or enhance the effects of anandamide on these two processes. We compared the effects of the novel compounds with those produced by a previously developed selective inhibitor, N-arachidonoyl-(2-methyl-4-hydroxyphenyl)amine (VDM-11). When assayed alone, OMDM-1 and OMDM-2 (1-10 mg/kg, i.p.) did not affect any of the five motor parameters under investigation, although the former compound exhibited a trend for the inhibition of ambulation, fast movements, and speed in rats. OMDM-2 and, to a lesser extent, VDM-11 (5 mg/kg, i.p.) enhanced the motor-inhibitory effects of a noneffective dose (2 mg/kg, i.p.) of anandamide, while OMDM-1 did not. In a typical test of acute analgesia, OMDM-2 and VDM-11 (1-10 mg/kg, i.p.), but not OMDM-1, significantly enhanced the time spent by rats on a "hot plate." However, the same compounds (5 mg/kg, i.p.) did not enhance the analgesic effect of a subeffective dose (2 mg/kg, i.p.) of anandamide, whereas OMDM-1 exerted a strong trend towards potentiation (P=0.06). We next explored the possible use of the two novel compounds in a pathological condition. Thus, we determined if, like other previously developed anandamide reuptake inhibitors, OMDM-1 and OMDM-2 inhibit spasticity in an animal model of multiple sclerosis-the chronic relapsing experimental allergic encephalomyelitis in mice. As previously shown with a higher dose of VDM-11, both novel compounds (5 mg/kg, i.v.) significantly reduced spasticity of the hindlimb in mice with chronic relapsing experimental allergic encephalomyelitis. We suggest that OMDM-1 and, particularly, OMDM-2 are useful pharmacological tools for the study of the (patho)physiological role of the anandamide cellular uptake process, and represent unique templates for the development of new antispastic drugs.
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Affiliation(s)
- Eva de Lago
- Departamento de Bioquímica y Biología Molecular III, Facultad de Medicina, Universidad Complutense, Ciudad Universitaria s/n, Madrid 28040, Spain
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97
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Zoratti C, Kipmen-Korgun D, Osibow K, Malli R, Graier WF. Anandamide initiates Ca(2+) signaling via CB2 receptor linked to phospholipase C in calf pulmonary endothelial cells. Br J Pharmacol 2003; 140:1351-62. [PMID: 14645143 PMCID: PMC1574152 DOI: 10.1038/sj.bjp.0705529] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The endocannabinoid anandamide has been reported to affect neuronal cells, immune cells and smooth muscle cells via either CB1 or CB2 receptors. In endothelial cells, the receptors involved in activating signal transduction are still unclear, despite the fact that anandamide is produced in this cell type. The present study was designed to explore in detail the effect of this endocannabinoid on Ca2+ signaling in single cells of a calf pulmonary endothelial cell line. Anandamide initiated a transient Ca2+ elevation that was prevented by the CB2 receptor antagonist SR144528, but not by the CB1 antagonist SR141716A. These data were confirmed by molecular identification of the bovine CB2 receptor in these endothelial cells by partial sequencing. The phospholipase C inhibitor 1-[6-[[(17beta)-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5dione and the inositol 1,4,5-trisphosphate receptor antagonist 2-aminoethoxydiphenylborate prevented Ca2+ signaling in response to anandamide. Using an improved cameleon probe targeted to the endoplasmic reticulum (ER), fura-2 and ratiometric-pericam, which is targeted to the mitochondria, anandamide was found to induce Ca2+ depletion of the ER accompanied by the activation of capacitative Ca2+ entry (CCE) and a transient elevation of mitochondrial Ca2+. These data demonstrate that anandamide stimulates the endothelial cells used in this study via CB2 receptor-mediated activation of phospholipase C, formation of inositol 1,4,5-trisphosphate, Ca2+ release from the ER and subsequent activation of CCE. Moreover, the cytosolic Ca2+ elevation was accompanied by a transient Ca2+ increase in the mitochondria. Thus, in addition to its actions on smooth muscle cells, anandamide also acts as a powerful stimulus for endothelial cells.
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MESH Headings
- Animals
- Arachidonic Acids/metabolism
- Arachidonic Acids/pharmacology
- Base Sequence
- Calcium/metabolism
- Calcium Channel Blockers/pharmacology
- Calcium Signaling
- Cannabinoid Receptor Modulators/metabolism
- Cannabinoid Receptor Modulators/pharmacology
- Cattle
- Cell Line
- Endocannabinoids
- Endoplasmic Reticulum/drug effects
- Endoplasmic Reticulum/metabolism
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Humans
- Mice
- Mitochondria/drug effects
- Mitochondria/metabolism
- Molecular Sequence Data
- Polyunsaturated Alkamides
- Pulmonary Artery/cytology
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/physiology
- Reverse Transcriptase Polymerase Chain Reaction
- Type C Phospholipases/antagonists & inhibitors
- Type C Phospholipases/metabolism
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Affiliation(s)
- Cristina Zoratti
- Department of Medical Biochemistry and Medical Molecular Biology, Karl-Franzens, University of Graz, Harrachgasse 21/III, Graz A-8010, Austria
| | - Dijle Kipmen-Korgun
- Department of Medical Biochemistry and Medical Molecular Biology, Karl-Franzens, University of Graz, Harrachgasse 21/III, Graz A-8010, Austria
| | - Karin Osibow
- Department of Medical Biochemistry and Medical Molecular Biology, Karl-Franzens, University of Graz, Harrachgasse 21/III, Graz A-8010, Austria
| | - Roland Malli
- Department of Medical Biochemistry and Medical Molecular Biology, Karl-Franzens, University of Graz, Harrachgasse 21/III, Graz A-8010, Austria
| | - Wolfgang F Graier
- Department of Medical Biochemistry and Medical Molecular Biology, Karl-Franzens, University of Graz, Harrachgasse 21/III, Graz A-8010, Austria
- Author for correspondence:
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98
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Abstract
The endocannabinoids N-arachidonylethanolamine (AEA or anandamide) and 2-arachidonylglycerol (2-AG) are hypothesized to function in the brain as interneuronal signaling molecules. Prevailing models of the actions of these molecules require that they traverse cellular plasma membranes twice; first, following cellular synthesis and second, prior to enzymatic hydrolysis. The transmembrane movement of AEA has been studied in multiple laboratories with a primary focus on its cellular accumulation following extracellular administration. Although there are areas of consensus among laboratories regarding AEA accumulation, several aspects are very unclear. In particular, there is a lack of consensus in the literature regarding the importance of AEA hydrolysis by fatty acid amide hydrolase in maintaining the driving force for accumulation. Furthermore, evidence for and against a transmembrane carrier protein has been published. We have reviewed the available literature and present a working model of the processes that are involved in the cellular accumulation of AEA. It is our hypothesis that transmembrane movement of AEA is regulated by concentration gradient between extracellular and intracellular free AEA. Furthermore, it is our view that a significant portion of the intracellular AEA in most cells is sequestered either by a protein or lipid compartment and that AEA sequestered in this manner does not equilibrate directly with the extracellular pool. Finally, we discuss the available data that have been presented in support of a transmembrane carrier protein for AEA.
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Affiliation(s)
- Cecilia J Hillard
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
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99
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Souza HCD, Salgado HC, Ballejo G, Salgado MCO. SR141716A-sensitive enhancement of ET-1 hypotensive effect by chronic NOS inhibition. Hypertension 2003; 42:802-5. [PMID: 12913062 DOI: 10.1161/01.hyp.0000088362.50484.4c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The present study evaluated the potential mechanism involved in the hypotensive effect induced by ET-1 in rats treated with the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) in the drinking water during 7 days. Hypertension developed in the L-NAME-treated rats (164+/-3 versus 112+/-1 mm Hg in untreated control rats), and the hypotensive effect of ET-1 (100 pmol/kg IV) was significantly enhanced compared with control rats (32+/-2% versus 20+/-1% fall in mean arterial pressure). The enhanced ET-1 hypotensive effect in L-NAME-treated rats was abolished by the ETB receptor antagonist BQ-788 but was unaltered by the cyclooxygenase inhibitor diclofenac, the cytochrome P450 inhibitor fluconazole, or the potassium channel blockers apamin, glibenclamide, tetraethylammonium, and 4-aminopyridine. Pretreatment with the cannabinoid CB1 receptor antagonist SR141716A significantly reduced the hypotensive response to ET-1 in L-NAME-treated rats (20+/-1%), although it did not modify the response in untreated control rats (17+/-1%). These findings indicate that in rats under chronic NOS inhibition, the hypotensive effect of ET-1 is unexpectedly enhanced and appears to be mediated by a non-NO/non-prostanoid mechanism and involves an SR141716A-sensitive mechanism triggered by ETB receptor activation.
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Affiliation(s)
- Hugo C D Souza
- Department of Pharmacology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil
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100
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Abstract
A large body of evidence now exists to substantiate that the endocannabinoid, anandamide, activates TRPV1 receptors. It is a low intrinsic efficacy TRPV1 agonist that behaves as a partial agonist in tissues with a low receptor reserve, while in tissues with high receptor reserve and in circumstances associated with certain disease states, it behaves as a full agonist. The efficacy of anandamide as a TRPV1 agonist is influenced by a succession of factors including receptor reserve, phosphorylation, metabolism and uptake, CB1 receptor activation, voltage, temperature, pH and bovine serum albumin. There are indications that the endocannabinoid system may play a role in the modulation of TRPV1 receptor activation. The activation of TRPV1 receptors by anandamide has potential implications in the treatment of inflammatory, respiratory and cardiovascular disorders. The relative importance of anandamide as a physiological and/or pathophysiological TRPV1 receptor agonist in comparison to other potential candidates has yet to be revealed.
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Affiliation(s)
- Ruth A Ross
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland.
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