1
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Dongdem JT, Helegbe GK, Opare-Asamoah K, Wezena CA, Ocloo A. Assessment of NSAIDs as potential inhibitors of the fatty acid amide hydrolase I (FAAH-1) using three different primary fatty acid amide substrates in vitro. BMC Pharmacol Toxicol 2022; 23:1. [PMID: 34983657 PMCID: PMC8725537 DOI: 10.1186/s40360-021-00539-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 10/27/2021] [Indexed: 12/23/2022] Open
Abstract
Background Pain relief remains a major subject of inadequately met need of patients. Therapeutic agents designed to treat pain and inflammation so far have low to moderate efficiencies with significant untoward side effects. FAAH-1 has been proposed as a promising target for the discovery of drugs to treat pain and inflammation without significant adverse effects. FAAH-1 is the primary enzyme accountable for the degradation of AEA and related fatty acid amides. Studies have revealed that the simultaneous inhibition of COX and FAAH-1 activities produce greater pharmacological efficiency with significantly lowered toxicity and ulcerogenic activity. Recently, the metabolism of endocannabinoids by COX-2 was suggested to be differentially regulated by NSAIDs. Methods We analysed the affinity of oleamide, arachidonamide and stearoylamide at the FAAH-1 in vitro and investigated the potency of selected NSAIDs on the hydrolysis of endocannabinoid-like molecules (oleamide, arachidonamide and stearoylamide) by FAAH-1 from rat liver. NSAIDs were initially screened at 500 μM after which those that exhibited greater potency were further analysed over a range of inhibitor concentrations. Results The substrate affinity of FAAH-1 obtained, increased in a rank order of oleamide < arachidonamide < stearoylamide with resultant Vmax values in a rank order of arachidonamide > oleamide > stearoylamide. The selected NSAIDs caused a concentration-dependent inhibition of FAAH-1 activity with sulindac, carprofen and meclofenamate exhibiting the greatest potency. Michaelis-Menten analysis suggested the mode of inhibition of FAAH-1 hydrolysis of both oleamide and arachidonamide by meclofenamate and indomethacin to be non-competitive in nature. Conclusion Our data therefore suggest potential for study of these compounds as combined FAAH-1-COX inhibitors. Supplementary Information The online version contains supplementary material available at 10.1186/s40360-021-00539-1.
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Affiliation(s)
- Julius T Dongdem
- Department of Biochemistry and Molecular Medicine, School of Medicine, University for Development Studies, Tamale-Campus, Tamale, Ghana. .,School of Life Sciences, University of Nottingham Medical School, NG7 2UH, Nottinghamshire, UK.
| | - Gideon K Helegbe
- Department of Biochemistry and Molecular Medicine, School of Medicine, University for Development Studies, Tamale-Campus, Tamale, Ghana
| | - Kwame Opare-Asamoah
- Department of Physiology and Biophysics, School of Medicine, University for Development Studies, Tamale-Campus, Tamale, Ghana
| | - Cletus A Wezena
- Department of Microbiology, Faculty of Bioscience, University for Development Studies, Nyankpala Campus, Tamale, Ghana
| | - Augustine Ocloo
- Department of Biochemistry, Cell and Molecular Biology University of Ghana, Legon, Accra, Ghana
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2
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Abstract
Non-steroidal anti-inflammatory drugs produce antinociceptive effects mainly through peripheral cyclooxygenase inhibition. In opposition to the classical non-steroidal anti-inflammatory drugs, paracetamol and dipyrone exert weak anti-inflammatory activity, their antinociceptive effects appearing to be mostly due to mechanisms other than peripheral cyclooxygenase inhibition. In this review, we classify classical non-steroidal anti-inflammatory drugs, paracetamol and dipyrone as “non-opioid analgesics” and discuss the mechanisms mediating participation of the endocannabinoid system in their antinociceptive effects. Non-opioid analgesics and their metabolites may activate cannabinoid receptors, as well as elevate endocannabinoid levels through different mechanisms: reduction of endocannabinoid degradation via fatty acid amide hydrolase and/or cyclooxygenase-2 inhibition, mobilization of arachidonic acid for the biosynthesis of endocannabinoids due to cyclooxygenase inhibition, inhibition of endocannabinoid cellular uptake directly or through the inhibition of nitric oxide synthase production, and induction of endocannabinoid release.
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Affiliation(s)
- Ruhan Deniz Topuz
- Department of Medical Pharmacology, Trakya University School of Medicine, Edirne, Turkey
| | - Özgur Gündüz
- Department of Medical Pharmacology, Trakya University School of Medicine, Edirne, Turkey
| | - Çetin Hakan Karadağ
- Department of Medical Pharmacology, Trakya University School of Medicine, Edirne, Turkey
| | - Ahmet Ulugöl
- Department of Medical Pharmacology, Trakya University School of Medicine, Edirne, Turkey
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3
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Charrua A, Matos R, Oliveira R, Marczylo T, Nagy I, Cruz F. Fatty acid amide hydrolase inhibition normalises bladder function and reduces pain through normalising the anandamide/palmitoylethanolamine ratio in the inflamed bladder of rats. Naunyn Schmiedebergs Arch Pharmacol 2019; 393:263-272. [PMID: 31522241 DOI: 10.1007/s00210-019-01729-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 09/06/2019] [Indexed: 12/27/2022]
Abstract
Fatty acid amide hydrolase inhibition may be used to control bladder function and pain by modulating endocannabinoid levels in cystitis. We studied the effect of the peripherally restricted fatty acid amide hydrolase inhibitor URB937 in bladder reflex activity and bladder pain using the lipopolysaccharide model of cystitis. We also correlated the URB937's effects with tissue levels of the endocannabinoids anandamide and palmitoylethanolamine. URB937 did not change the reflex activity of normal bladders. In inflamed bladders, URB937 had a U-shaped dose-response curve; following an initial cannabinoid receptor type 1-mediated reduction in pain responses and normalisation of bladder reflex activity, URB937 gradually increased both pain responses and bladder reflex activity through the transient receptor potential ion channel subfamily V member 1. Chronic cystitis increased the tissue levels of anandamide and decreased those of palmitoylethanolamine. At the dose that normalised bladder reflex activity and decreased pain responses, URB937 normalised the levels of anandamide and palmitoylethanolamine in the bladder. At high doses that induced excitatory effects, URB937 apparently did not change anandamide and palmitoylethanolamine levels, which therefore were in the range of the inflamed bladder. Fatty acid amide hydrolase inhibition results in complex changes in bladder endocannabinoid levels. The therapeutic effect of fatty acid amide hydrolase inhibitors is not related to increase in anandamide levels but rather a normalisation of the anandamide and palmitoylethanolamine level ratio.
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Affiliation(s)
- Ana Charrua
- Departamento de Biomedicina-Unidade de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, Rua Dr. Plácido da Costa, 91, 4200, Porto, Portugal. .,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal. .,IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
| | - Rita Matos
- Departamento de Biomedicina-Unidade de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, Rua Dr. Plácido da Costa, 91, 4200, Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,IPATIMUP-Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto, Portugal
| | - Raquel Oliveira
- Departamento de Biomedicina-Unidade de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, Rua Dr. Plácido da Costa, 91, 4200, Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Tim Marczylo
- Toxicology Department, Public Health England, Chilton, UK
| | - Istvan Nagy
- Department of Surgery & Cancer, Faculty of Medicine, Imperial College London, London, UK
| | - Francisco Cruz
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,Departamento de Urologia, Hospital S. João, Porto, Portugal
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4
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Montanari S, Scalvini L, Bartolini M, Belluti F, Gobbi S, Andrisano V, Ligresti A, Di Marzo V, Rivara S, Mor M, Bisi A, Rampa A. Fatty Acid Amide Hydrolase (FAAH), Acetylcholinesterase (AChE), and Butyrylcholinesterase (BuChE): Networked Targets for the Development of Carbamates as Potential Anti-Alzheimer's Disease Agents. J Med Chem 2016; 59:6387-406. [PMID: 27309570 DOI: 10.1021/acs.jmedchem.6b00609] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The modulation of the endocannabinoid system is emerging as a viable avenue for the treatment of neurodegeneration, being involved in neuroprotective and anti-inflammatory processes. In particular, indirectly enhancing endocannabinoid signaling to therapeutic levels through FAAH inhibition might be beneficial for neurodegenerative disorders such as Alzheimer's disease, effectively preventing or slowing the progression of the disease. Hence, in the search for a more effective treatment for Alzheimer's disease, in this paper, the multitarget-directed ligand paradigm was applied to the design of carbamates able to simultaneously target the recently proposed endocannabinoid system and the classic cholinesterase system, and achieve effective dual FAAH/cholinesterase inhibitors. Among the two series of synthesized compounds, while some derivatives proved to be extremely potent on a single target, compounds 9 and 19 were identified as effective dual FAAH/ChE inhibitors, with well-balanced nanomolar activities. Thus, 9 and 19 might be considered as new promising candidates for Alzheimer's disease treatment.
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Affiliation(s)
- Serena Montanari
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Laura Scalvini
- Department of Pharmacy, University of Parma , Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Manuela Bartolini
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Federica Belluti
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Silvia Gobbi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Vincenza Andrisano
- Department for Life Quality Studies, Alma Mater Studiorum University of Bologna , Corso d'Augusto 237, 47921 Rimini, Italy
| | - Alessia Ligresti
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council , Via Campi Flegrei 34, 80078 Pozzuoli, NA, Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council , Via Campi Flegrei 34, 80078 Pozzuoli, NA, Italy
| | - Silvia Rivara
- Department of Pharmacy, University of Parma , Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Marco Mor
- Department of Pharmacy, University of Parma , Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Alessandra Bisi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Angela Rampa
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna , Via Belmeloro 6, 40126 Bologna, Italy
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5
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Morera E, Di Marzo V, Monti L, Allarà M, Schiano Moriello A, Nalli M, Ortar G, De Petrocellis L. Arylboronic acids as dual-action FAAH and TRPV1 ligands. Bioorg Med Chem Lett 2016; 26:1401-5. [PMID: 26850005 DOI: 10.1016/j.bmcl.2016.01.071] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 01/22/2016] [Accepted: 01/23/2016] [Indexed: 12/17/2022]
Abstract
A series of 31 arylboronic acids designed on the basis of the pharmacophore model for a variety of TRPV1 antagonists was prepared and tested on FAAH and TRPV1 channel. Four of them, that is, compounds 3c, 4a, 5a,b acted as dual FAAH/TRPV1 blockers with IC50 values between 0.56 and 8.11μM whereas ten others (compounds 1c,f-i, 2c-f, 4b) inhibited FAAH and activated/desensitized TRPV1.
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Affiliation(s)
- Enrico Morera
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, piazzale Aldo Moro 5, 00185 Roma, Italy.
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli (Napoli), Italy
| | - Ludovica Monti
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, piazzale Aldo Moro 5, 00185 Roma, Italy
| | - Marco Allarà
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli (Napoli), Italy
| | - Aniello Schiano Moriello
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli (Napoli), Italy
| | - Marianna Nalli
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, piazzale Aldo Moro 5, 00185 Roma, Italy
| | - Giorgio Ortar
- Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, piazzale Aldo Moro 5, 00185 Roma, Italy
| | - Luciano De Petrocellis
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli (Napoli), Italy.
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6
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Karlsson J, Fowler CJ. Inhibition of endocannabinoid metabolism by the metabolites of ibuprofen and flurbiprofen. PLoS One 2014; 9:e103589. [PMID: 25061885 PMCID: PMC4111603 DOI: 10.1371/journal.pone.0103589] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 06/28/2014] [Indexed: 02/02/2023] Open
Abstract
Background In addition to their effects upon prostaglandin synthesis, the non-steroidal anti-inflammatory drugs ibuprofen and flurbiprofen inhibit the metabolism of the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA) by cyclooxygenase-2 (COX-2) and fatty acid amide hydrolase (FAAH), respectively. Here, we investigated whether these effects upon endocannabinoid metabolism are shared by the main metabolites of ibuprofen and flurbiprofen. Methodology/Principal Findings COX activities were measured via changes in oxygen consumption due to oxygenation of arachidonic acid (for COX-1) and arachidonic acid and 2-AG (for COX-2). FAAH activity was quantified by measuring hydrolysis of tritium labelled AEA in rat brain homogenates. The ability of ibuprofen and flurbiprofen to inhibit COX-2-catalysed oxygenation of 2-AG at lower concentrations than the oxygenation of arachidonic acid was seen with 4′-hydroxyflurbiprofen and possibly also 3′-hydroxyibuprofen, albeit at lower potencies than the parent compounds. All ibuprofen and flurbiprofen metabolites retained the ability to inhibit FAAH in a pH-dependent manner, although the potency was lower than seen with the parent compounds. Conclusions/Significance It is concluded that the primary metabolites of ibuprofen and flurbiprofen retain some of the properties of the parent compound with respect to inhibition of endocannabinoid metabolism. However, these effects are unlikely to contribute to the actions of the parent compounds in vivo.
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Affiliation(s)
- Jessica Karlsson
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden
- * E-mail:
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7
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Bertolacci L, Romeo E, Veronesi M, Magotti P, Albani C, Dionisi M, Lambruschini C, Scarpelli R, Cavalli A, De Vivo M, Piomelli D, Garau G. A binding site for nonsteroidal anti-inflammatory drugs in fatty acid amide hydrolase. J Am Chem Soc 2012; 135:22-5. [PMID: 23240907 DOI: 10.1021/ja308733u] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In addition to inhibiting the cyclooxygenase (COX)-mediated biosynthesis of prostanoids, various widely used nonsteroidal anti-inflammatory drugs (NSAIDs) enhance endocannabinoid signaling by blocking the anandamide-degrading membrane enzyme fatty acid amide hydrolase (FAAH). The X-ray structure of FAAH in complex with the NSAID carprofen, along with site-directed mutagenesis, enzyme activity assays, and NMR analysis, has revealed the molecular details of this interaction, providing information that may guide the design of dual FAAH-COX inhibitors with superior analgesic efficacy.
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Affiliation(s)
- Laura Bertolacci
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genoa, Italy
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8
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Rakers C, Zoerner AA, Engeli S, Batkai S, Jordan J, Tsikas D. Stable isotope liquid chromatography-tandem mass spectrometry assay for fatty acid amide hydrolase activity. Anal Biochem 2011; 421:699-705. [PMID: 22146559 DOI: 10.1016/j.ab.2011.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/03/2011] [Accepted: 11/04/2011] [Indexed: 11/15/2022]
Abstract
Fatty acid amide hydrolase (FAAH) is the main enzyme responsible for the hydrolysis of the endocannabinoid anandamide (arachidonoyl ethanolamide, AEA) to arachidonic acid (AA) and ethanolamine (EA). Published FAAH activity assays mostly employ radiolabeled anandamide or synthetic fluorogenic substrates. We report a stable isotope liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for specific, sensitive, and high-throughput capable FAAH activity measurements. The assay uses AEA labeled with deuterium on the EA moiety (d₄-AEA) as substrate and measures the specific reaction product tetradeutero-EA (d₄-EA) and the internal standard ¹³C₂-EA. Selected reaction monitoring of m/z 66→m/z 48 (d₄-EA) and m/z 64→m/z 46 (¹³C₂-EA) in the positive electrospray ionization mode after liquid chromatographic separation on a HILIC (hydrophilic interaction liquid chromatography) column is performed. The assay was developed and thoroughly validated using recombinant human FAAH (rhFAAH) and then was applied to human blood and dog liver samples. rhFAAH-catalyzed d₄-AEA hydrolysis obeyed Michaelis-Menten kinetics (K(M)=12.3 μM, V(max)=27.6 nmol/min mg). Oleoyl oxazolopyridine (oloxa) was a potent, partial noncompetitive inhibitor of rhFAAH (IC₅₀=24.3 nM). Substrate specificity of other fatty acid ethanolamides decreased with decreasing length, number of double bonds, and lipophilicity of the fatty acid skeleton. In human whole blood, we detected FAAH activity that was inhibited by oloxa.
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Affiliation(s)
- Christin Rakers
- Institute of Clinical Pharmacology, Hannover Medical School, 30623 Hannover, Germany
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9
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Tian G, Paschetto KA, Gharahdaghi F, Gordon E, Wilkins DE, Luo X, Scott CW. Mechanism of inhibition of fatty acid amide hydrolase by sulfonamide-containing benzothiazoles: long residence time derived from increased kinetic barrier and not exclusively from thermodynamic potency. Biochemistry 2011; 50:6867-78. [PMID: 21728345 DOI: 10.1021/bi200552p] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fatty acid amide hydrolase (FAAH) has emerged as a potential target for developing analgesic, anxiolytic, antidepressant, sleep-enhancing, and anti-inflammatory drugs, and tremendous efforts have been made to discover potent and selective inhibitors of FAAH. Most known potent FAAH inhibitors described to date employ covalent mechanisms, inhibiting the enzyme either reversibly or irreversibly. Recently, a benzothiazole-based analogue (1) has been described possessing a high potency against FAAH yet lacking a structural feature previously known to interact with FAAH covalently. However, covalent inhibition of FAAH by 1 has not been fully ruled out, and the issue of reversibility has not been addressed. Confirming previous reports, 1 inhibited recombinant human FAAH (rhFAAH) with high potency with IC(50) ~2 nM. It displayed an apparently noncompetitive and irreversible inhibition, titrating rhFAAH stoichiometrically within normal assay times. The inhibition appeared to be time dependent, but the time dependence only improved potency by a small degree (from ~8 to ~2 nM). However, mass spectrometric analyses of the reaction mixture failed to reveal any cleavage product or covalent adduct and showed full recovery of the parent compound, ruling out covalent, irreversible inhibition. Dialysis revealed recovery of enzyme activity from enzyme-inhibitor complex over a prolonged time (>10 h), demonstrating that 1 is indeed a reversible, albeit slowly dissociating inhibitor of FAAH. Molecular docking indicated that the sulfonamide group of 1 could form hydrogen bonds with several residues involved in catalysis, thereby mimicking the transition state. The long residence time displayed by 1 does not appear to derive exclusively from great thermodynamic potency and is consistent with an increased kinetic energy barrier that prevents dissociation from happening quickly.
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Affiliation(s)
- Gaochao Tian
- AstraZeneca Pharmaceuticals, Wilmington, Delaware 19850, United States.
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10
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Onnis V, Congiu C, Björklund E, Hempel F, Söderström E, Fowler CJ. Synthesis and evaluation of paracetamol esters as novel fatty acid amide hydrolase inhibitors. J Med Chem 2010; 53:2286-98. [PMID: 20143779 DOI: 10.1021/jm901891p] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fatty acid amide hydrolase (FAAH) is the key hydrolytic enzyme for the endogenous cannabinoid receptor ligand anandamide. The synthesis and evaluation for their FAAH inhibitory activities of a series of 18 paracetamol esters are described. Structure-activity relationship studies indicated that the ester (33) with a 2-(4-(2-(trifluoromethyl)pyridin-4-ylamino)phenyl)acetic acid substituent was the most potent analogue in this series. The compound inhibited FAAH activity in a competitive manner with a K(i) value of 0.16 microM. The compound was also able to inhibit the FAAH activity in rat basophilic leukemia cells as assessed by measuring either the hydrolysis of anandamide, the FAAH-dependent cellular accumulation of anandamide, or the FAAH-dependent recycling of tritium to the cell membranes. The compound also inhibited the activity of monoacylglycerol lipase (MGL), the enzyme responsible for the hydrolysis of the endogenous cannabinoid receptor ligand 2-arachidonoylglycerol, with an IC(50) value of 1.9 microM. It is concluded that the compound may be a useful template for the design of potent novel inhibitors of FAAH.
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Affiliation(s)
- Valentina Onnis
- Department of Toxicology, Unit of Medicinal Chemistry, University of Cagliari, via Ospedale 72, Cagliari I-09124, Italy.
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11
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Hamza M, Dionne RA. Mechanisms of non-opioid analgesics beyond cyclooxygenase enzyme inhibition. Curr Mol Pharmacol 2010; 2:1-14. [PMID: 19779578 DOI: 10.2174/1874467210902010001] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Non-opioid analgesics including both selective and non-selective cyclooxygenase (COX) inhibitors and acetaminophen are the most widely used treatments for pain. Inhibition of COX is thought to be largely responsible for both the therapeutic and adverse effects of this class of drugs. Accumulating evidence over the past two decades has demonstrated effects of non-opioids beyond the inhibition of COX and prostaglandin synthesis that might also explain their therapeutic and adverse effects. These include their interaction with endocannabinoids, nitric oxide, monoaminergic, and cholinergic systems. Moreover, the recent development of microarray technology that allows the study of human gene expression suggests multiple pathways that may be related to the analgesic and anti-inflammatory effects of non-opioids. The present review will discuss the multiple actions of non-opioids and their interactions with these systems during inflammation and pain, suggesting that COX inhibition is an incomplete explanation for the actions of non-opioids and proposes the involvement of multiple selective targets for their analgesic, as well as, their adverse effects.
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Affiliation(s)
- May Hamza
- National Institute of Nursing Research, NIH, Bethesda, MD 20892, USA
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12
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Costa B, Bettoni I, Petrosino S, Comelli F, Giagnoni G, Di Marzo V. The dual fatty acid amide hydrolase/TRPV1 blocker, N-arachidonoyl-serotonin, relieves carrageenan-induced inflammation and hyperalgesia in mice. Pharmacol Res 2010; 61:537-46. [PMID: 20138997 DOI: 10.1016/j.phrs.2010.02.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Revised: 01/18/2010] [Accepted: 02/01/2010] [Indexed: 01/08/2023]
Abstract
Given that the pharmacological or genetic inactivation of fatty acid amide hydrolase (FAAH) counteracts pain and inflammation, and on the basis of the established involvement of transient receptor potential vanilloid type-1 (TRPV1) channels in inflammatory pain, we tested the capability of a dual FAAH/TRPV1 blocker, N-arachidonoyl-serotonin (AA-5-HT), to relieve oedema and pain in a model of acute inflammation, and compared its efficacy with that of a single FAAH inhibitor (URB597) or TRPV1 antagonist (capsazepine). Acute inflammation was induced by intraplantar injection of lambda-carrageenan into mice and the anti-inflammatory and anti-nociceptive actions of AA-5-HT were assessed at different doses, time points and treatment schedule. In addition, endocannabinoid levels were measured in paw skin and spinal cord. Systemic administration of AA-5-HT elicited dose-dependent anti-oedemigen and anti-nociceptive effects, whereas it was devoid of efficacy when given locally. When tested in a therapeutic regimen, the compound retained comparable anti-inflammatory effects. TRPV1 receptor mediated the anti-inflammatory property of AA-5-HT, whereas both CB(1) and TRPV1 receptors were involved in its anti-hyperalgesic activity. These effects were accompanied by an increase of the levels of the endocannabinoid anandamide (AEA) in both inflamed paw and spinal cord. AA-5-HT was more potent than capsazepine as anti-oedemigen and anti-hyperalgesic drug, whereas it shows an anti-oedemigen property similar to URB597, which was, however, devoid of the anti-nociceptive effect. AA-5-HT did not induce unwanted effects on locomotion and body temperature. In conclusion AA-5-HT has both anti-inflammatory and anti-hyperalgesic properties and its employment offers advantages, in terms of efficacy and lack of adverse effects, deriving from its dual activity.
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Affiliation(s)
- Barbara Costa
- Department of Biotechnology and Bioscience, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy.
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13
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Qiao L, Chen CS, Zhang SC. Significance of expression of fatty acid amide hydrolase in normal colon wall. Shijie Huaren Xiaohua Zazhi 2009; 17:2266-2271. [DOI: 10.11569/wcjd.v17.i22.2266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the significance of expression of fatty acid amide hydrolase (FAAH) in normal colon wall.
METHODS: Sixteen normal colon specimens were collected from the ascending colon (five cases), descending colon (three cases) and sigmoid colon (eight cases) in patients treated at our hospital due to colon polyps or undergoing colostomy . The expression of FAAH mRNA and protein in these specimens was detected by RT-PCR, immunohistochemistry and Western blot, respectively. The expression patterns of FAAH and cannabinoid receptor 1 (CB1) were compared by immunofluorescent staining.
RESULTS: Positive staining for FAAH was observed in the cytoplasm of myenteric neurons in the intestinal wall in different colonic segments. Obvious positive staining was also noted in mucosal glands and the cytoplasm of absorptive cells. Semi-quantitative analysis showed that there were no significant differences in the staining intensity among different colonic segments (all P > 0.05). Similar result was obtained by Western blot (all P > 0.05). Real-time PCR results showed that there were also no significant differences in FAAH mRNA expression levels among different colonic segments (all P > 0.05). Immunofluorescence staining showed that both FAAH and CB1 could be detected in the cytoplasm of myenteric neurons in the intestinal walls, and they were distributed in a complementary pattern.
CONCLUSION: FAAH is expressed in normal colon wall. There are no significant differences in the expression levels of FAAH among different colonic segments. FAAH and CB1 are distributed in a complementary pattern.
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Seierstad M, Breitenbucher JG. Discovery and development of fatty acid amide hydrolase (FAAH) inhibitors. J Med Chem 2009; 51:7327-43. [PMID: 18983142 DOI: 10.1021/jm800311k] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mark Seierstad
- Johnson & Johnson Pharmaceutical Research and Development, L.L.C., 3210 Merryfield Row, San Diego, California 92121, USA
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15
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Fowler CJ, Naidu PS, Lichtman A, Onnis V. The case for the development of novel analgesic agents targeting both fatty acid amide hydrolase and either cyclooxygenase or TRPV1. Br J Pharmacol 2009; 156:412-9. [PMID: 19226258 PMCID: PMC2697682 DOI: 10.1111/j.1476-5381.2008.00029.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 08/19/2008] [Accepted: 08/22/2008] [Indexed: 12/19/2022] Open
Abstract
Although the dominant approach to drug development is the design of compounds selective for a given target, compounds targeting more than one biological process may have superior efficacy, or alternatively a better safety profile than standard selective compounds. Here, this possibility has been explored with respect to the endocannabinoid system and pain. Compounds inhibiting the enzyme fatty acid amide hydrolase (FAAH), by increasing local endocannabinoid tone, produce potentially useful effects in models of inflammatory and possibly neuropathic pain. Local increases in levels of the endocannabinoid anandamide potentiate the actions of cyclooxygenase inhibitors, raising the possibility that compounds inhibiting both FAAH and cyclooxygenase can be as effective as non-steroidal anti-inflammatory drugs but with a reduced cyclooxygenase inhibitory 'load'. An ibuprofen analogue active in models of visceral pain and with FAAH and cyclooxygenase inhibitory properties has been identified. Another approach, built in to the experimental analgesic compound N-arachidonoylserotonin, is the combination of FAAH inhibitory and transient receptor potential vanilloid type 1 antagonist properties. Although finding the right balance of actions upon the two targets is a key to success, it is hoped that dual-action compounds of the types illustrated in this review will prove to be useful analgesic drugs.
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Affiliation(s)
- C J Fowler
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Sweden.
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16
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Naidu PS, Booker L, Cravatt BF, Lichtman AH. Synergy between enzyme inhibitors of fatty acid amide hydrolase and cyclooxygenase in visceral nociception. J Pharmacol Exp Ther 2008; 329:48-56. [PMID: 19118134 DOI: 10.1124/jpet.108.143487] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The present study investigated whether inhibition of fatty acid amide hydrolase (FAAH), the enzyme responsible for anandamide catabolism, produces antinociception in the acetic acid-induced abdominal stretching model of visceral nociception. Genetic deletion or pharmacological inhibition of FAAH reduced acetic acid-induced abdominal stretching. Transgenic mice that express FAAH exclusively in the nervous system displayed the antinociceptive phenotype, indicating the involvement of peripheral fatty acid amides. The cannabinoid receptor 1 (CB(1)) receptor antagonist, rimonabant, but not the cannabinoid receptor 2 (CB(2)) receptor antagonist, SR144528, blocked the antinociceptive phenotype of FAAH(-/-) mice and the analgesic effects of URB597 (3'-carbamoyl-biphenyl-3-yl-cyclohexylcarbamate) or OL-135 (1-oxo-1[5-(2-pyridyl)-2-yl]-7-phenyl heptane), respective irreversible and reversible FAAH inhibitors, administered to C57BL/6 mice. The opioid receptor antagonist, naltrexone, did not block the analgesic effects of either FAAH inhibitor. URB597, ED(50) [95% confidence interval (CI) = 2.1 (1.5-2.9) mg/kg], and the nonselective cyclooxygenase inhibitor, diclofenac sodium [ED(50) (95% CI) = 9.8 (8.2-11.7) mg/kg], dose-dependently inhibited acetic acid-induced abdominal stretching. Combinations of URB597 and diclofenac yielded synergistic analgesic interactions according to isobolographic analysis. It is important that FAAH(-/-) mice and URB597-treated mice displayed significant reductions in the severity of gastric irritation caused by diclofenac. URB597 lost its gastroprotective effects in CB(1)(-/-) mice, whereas it maintained its efficacy in CB(2)(-/-) mice, indicating a CB(1) mechanism of action. Taken together, the results of the present study suggest that FAAH represents a promising target for the treatment of visceral pain, and a combination of FAAH inhibitors and NSAIDs may have great utility to treat visceral pain, with reduced gastric toxicity.
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Affiliation(s)
- Pattipati S Naidu
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, Virginia 23298-0613, USA
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17
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Ortar G, Cascio MG, De Petrocellis L, Morera E, Rossi F, Schiano-Moriello A, Nalli M, de Novellis V, Woodward DF, Maione S, Di Marzo V. New N-Arachidonoylserotonin Analogues with Potential “Dual” Mechanism of Action against Pain. J Med Chem 2007; 50:6554-69. [DOI: 10.1021/jm070678q] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Giorgio Ortar
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Maria Grazia Cascio
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Luciano De Petrocellis
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Enrico Morera
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Francesca Rossi
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Aniello Schiano-Moriello
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Marianna Nalli
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Vito de Novellis
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - David F. Woodward
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Sabatino Maione
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
| | - Vincenzo Di Marzo
- Dipartimento di Studi Farmaceutici, University of Rome “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy, Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Endocannabinoid Research Group, Institute of Cybernetics, Consiglio Nazionale delle Ricerche, Via dei Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy, Department of Biological Sciences, Allergan, Inc., 2525 Dupont Drive (RD-2C), Irvine,
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Jhaveri MD, Richardson D, Chapman V. Endocannabinoid metabolism and uptake: novel targets for neuropathic and inflammatory pain. Br J Pharmacol 2007; 152:624-32. [PMID: 17704819 PMCID: PMC2190014 DOI: 10.1038/sj.bjp.0707433] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Revised: 07/23/2007] [Accepted: 07/25/2007] [Indexed: 12/14/2022] Open
Abstract
Cannabinoid CB1 and CB2 receptors are located at key sites involved in the relaying and processing of noxious inputs. Both CB1 and CB2 receptor agonists have analgesic effects in a range of models of inflammatory and neuropathic pain. Importantly, clinical trials of cannabis-based medicines indicate that the pre-clinical effects of cannabinoid agonists may translate into therapeutic potential in humans. One of the areas of concern with this pharmacological approach is that CB1 receptors have a widespread distribution in the brain and that global activation of CB1 receptors is associated with adverse side effects. Studies of the endogenous cannabinoids (endocannabinoids) have demonstrated that they are present in most tissues and that in some pain states, such as neuropathic pain, levels of endocannabinoids are elevated at key sites involved in pain processing. An alternative approach that can be used to harness the potential therapeutic effects of cannabinoids is to maximise the effects of the endocannabinoids, the actions of which are terminated by re-uptake and metabolism by various enzymes, including fatty acid amide hydrolase (FAAH), monoacylglycerol lipase (MAGL) and cyclooxygenase type 2 (COX2). Preventing the metabolism, or uptake, of endocannabinoids elevates levels of these lipid compounds in tissue and produces behavioural analgesia in models of acute pain. Herein we review recent studies of the effects of inhibition of metabolism of endocannabinoids versus uptake of endocannabinoids on nociceptive processing in models of inflammatory and neuropathic pain.
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Affiliation(s)
- M D Jhaveri
- School of Biomedical Sciences, Institute of Neuroscience, Queens Medical Centre, Nottingham, UK.
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19
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Fowler CJ. The contribution of cyclooxygenase-2 to endocannabinoid metabolism and action. Br J Pharmacol 2007; 152:594-601. [PMID: 17618306 PMCID: PMC2190012 DOI: 10.1038/sj.bjp.0707379] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 06/13/2007] [Accepted: 06/14/2007] [Indexed: 11/09/2022] Open
Abstract
The development of sensitive analytical methods for measurement of endocannabinoids, their metabolites, and related lipids, has underlined the complexity of the endocannabinoid system. A case can be made for an 'endocannabinoid soup' (akin to the inflammatory soup) whereby the net effect of a pathological state and/or a pharmacological intervention on this system is the result not only of changes in endocannabinoid levels but also of their metabolites and related compounds that affect their function. With respect to the metabolism of anandamide and 2-arachidonoylglycerol, the main hydrolytic enzymes involved are fatty acid amide hydrolase and monoacylglycerol lipase. However, other pathways can come into play when these are blocked. Cyclooxygenase-2 derived metabolites of anandamide and 2-arachidonoylglycerol have a number of properties, including effects upon cell viability, contraction of the cat iris sphincter (an effect mediated by a novel receptor), mobilization of calcium and modulation of synaptic transmission. Nonsteroidal anti-inflammatory agents, whose primary mode of action is the inhibition of cyclooxygenase, can also interact with the endocannabinoid system both in vitro and in vivo. Other enzymes, such as the lipoxygenase and cytochrome P450 oxidative enzymes, can also metabolize endocannabinoids and produce biologically active compounds. It is concluded that sensitive analytical methods, which allow for measurement of endocannabinoids and related lipids, should provide vital information as to the importance of these alternative metabolic pathways when the primary hydrolytic endocannabinoid metabolizing enzymes are inhibited.
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Affiliation(s)
- C J Fowler
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden.
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20
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Transient receptor potential vanilloid 1 (TRPV1) channels in cultured rat Sertoli cells regulate an acid sensing chloride channel. Biochem Pharmacol 2007; 75:476-83. [PMID: 17945192 DOI: 10.1016/j.bcp.2007.09.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Revised: 09/03/2007] [Accepted: 09/04/2007] [Indexed: 01/24/2023]
Abstract
Sertoli cells provide a controlled microenvironment for regulation and maintenance of spermatogenesis for which an acidic milieu is crucial for male fertility. Sertoli cells also contribute to protection of spermatogenetic cells. Here, we showed that TRPV1 is expressed in rat Sertoli cells and regulates an acid sensing Cl(-) channel (ASCC). The expression of TRPV1 in rat Sertoli cells was demonstrated by RT-PCR, immunostaining and calcium measurement experiments. ASCC activity was inhibited by capsaicin (IC(50)=214.3+/-1.6 nM), olvanil (IC(50)=400+/-1.7 pM) and resiniferatoxin (IC(50)=9.3+/-1.5 nM) but potentiated by capsazepine (EC(50)=5.3+/-1.3 microM) and ruthenium red (EC(50)=2.3+/-1.5 microM). In the human airway epithelial cell line Calu-3 in which ASCC can be detected but not TRPV1, capsaicin and capsazepine were without any effect. Finally the application of the non-steroidal anti-inflammatory drug ibuprofen prevented the control of ASCC by TRPV1. Our study provides the first evidence for a regulation by TRPV1 of an acid sensing chloride channel in rat Sertoli cells. TRPV1 and ASCC may thus be considered as new potential physiological regulators of spermatogenesis and targets for pharmacological treatments of reproductive disorders as cryptorchidism, Sertoli cell tumors or torsion of the spermatic cord.
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21
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Lenman A, Fowler CJ. Interaction of ligands for the peroxisome proliferator-activated receptor gamma with the endocannabinoid system. Br J Pharmacol 2007; 151:1343-51. [PMID: 17592505 PMCID: PMC2189817 DOI: 10.1038/sj.bjp.0707352] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE There is good evidence that agents interacting with the endocannabinoid system in the body can also interact with the peroxisome proliferator-activated receptor gamma. The present study was designed to test whether the reverse is true, namely whether peroxisome proliferator-activated receptor gamma ligands have direct effects upon the activity of the endocannabinoid metabolizing enzyme fatty acid amide hydrolase. EXPERIMENTAL APPROACH Fatty acid amide hydrolase activity was measured in rat brain homogenates, C6 glioma and RBL2H3 basophilic leukaemia cells. Cellular uptake of anandamide was also assessed in these cells. KEY RESULTS Peroxisome proliferator-activated receptor gamma activators inhibited the metabolism of the endocannabinoid anandamide in rat brain homogenates with an order of potency MCC-555 > indomethacin approximately ciglitazone approximately 15-deoxy-Delta(12,14)-prostaglandin J(2) approximately pioglitazone > rosiglitazone > troglitazone. The antagonists BADGE, GW9662 and T0070907 were poor inhibitors of anandamide hydrolysis. The inhibition by ciglitazone was competitive and increased as the pH of the assay buffer was decreased; the K(i) value at pH 6.0 was 17 microM. In intact C6 glioma cells assayed at pH 6.2, significant inhibition of anandamide hydrolysis was seen at 3 microM ciglitazone, whereas 100 microM was required to produce significant inhibition at pH 7.4. Ciglitazone also interacted with monoacylglycerol lipase as well as with cannabinoid CB(1) and CB(2) receptors. CONCLUSIONS AND IMPLICATIONS Ciglitazone may be useful as a template for the design of novel dual action anti-inflammatory agents which are both inhibitors of fatty acid amide hydrolase and agonists at the peroxisome proliferator-activated receptor gamma.
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MESH Headings
- Amidohydrolases/drug effects
- Amidohydrolases/metabolism
- Animals
- Anti-Inflammatory Agents/administration & dosage
- Anti-Inflammatory Agents/pharmacology
- Brain/enzymology
- Brain Neoplasms/enzymology
- Brain Neoplasms/pathology
- Cannabinoid Receptor Modulators/metabolism
- Cell Line, Tumor
- Dose-Response Relationship, Drug
- Drug Design
- Endocannabinoids
- Glioma/enzymology
- Glioma/pathology
- Hydrogen-Ion Concentration
- Leukemia, Basophilic, Acute/enzymology
- Leukemia, Basophilic, Acute/pathology
- Ligands
- Male
- Monoacylglycerol Lipases/drug effects
- Monoacylglycerol Lipases/metabolism
- PPAR gamma/agonists
- Rats
- Rats, Sprague-Dawley
- Receptor, Cannabinoid, CB1/drug effects
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/drug effects
- Receptor, Cannabinoid, CB2/metabolism
- Thiazolidinediones/administration & dosage
- Thiazolidinediones/pharmacology
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Affiliation(s)
- A Lenman
- Department of Pharmacology and Clinical Neuroscience, Umeå University Umeå, Sweden
| | - C J Fowler
- Department of Pharmacology and Clinical Neuroscience, Umeå University Umeå, Sweden
- Author for correspondence:
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22
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Holt S, Paylor B, Boldrup L, Alajakku K, Vandevoorde S, Sundström A, Cocco MT, Onnis V, Fowler CJ. Inhibition of fatty acid amide hydrolase, a key endocannabinoid metabolizing enzyme, by analogues of ibuprofen and indomethacin. Eur J Pharmacol 2007; 565:26-36. [PMID: 17397826 DOI: 10.1016/j.ejphar.2007.02.051] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Revised: 02/05/2007] [Accepted: 02/26/2007] [Indexed: 12/24/2022]
Abstract
There is evidence in the literature that the nonsteroidal anti-inflammatory drugs indomethacin and ibuprofen can interact with the cannabinoid system both in vitro and in vivo. In the present study, a series of analogues of ibuprofen and indomethacin have been investigated with respect to their ability to inhibit fatty acid amide hydrolase, the enzyme responsible for the hydrolysis of the endogenous cannabinoid anandamide. Of the fourteen compounds tested, the 6-methyl-pyridin-2-yl analogue of ibuprofen ("ibu-am5") was selected for further study. This compound inhibited rat brain anandamide hydrolysis in a non-competitive manner, with IC50 values of 4.7 and 2.5 microM being found at pH 6 and 8, respectively. By comparison, the IC50 values for ibuprofen were 130 and 750 microM at pH 6 and 8, respectively. There was no measurable N-acylethanolamine hydrolyzing acid amidase activity in rat brain membrane preparations. In intact C6 glioma cells, ibu-am5 inhibited the hydrolysis of anandamide with an IC50 value of 1.2 microM. There was little difference in the potencies of ibu-am5 and ibuprofen towards cyclooxygenase-1 and -2 enzymes, and neither compound inhibited the activity of monoacylglycerol lipase. Ibu-am5 inhibited the binding of [3H]-CP55,940 to rat brain CB1 and human CB2 cannabinoid receptors more potently than ibuprofen, but the increase in potency was less than the corresponding increase in potency seen for inhibition of FAAH activity. It is concluded that ibu-am5 is an analogue of ibuprofen with a greater potency towards fatty acid amide hydrolase but with a similar cyclooxygenase inhibitory profile, and may be useful for the study of the therapeutic potential of combined fatty acid amide hydrolase-cyclooxygenase inhibitors.
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Affiliation(s)
- Sandra Holt
- Department of Pharmacology and Clinical Neuroscience, Umeå University, SE-901 87 Umeå, Sweden
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Maione S, De Petrocellis L, de Novellis V, Moriello AS, Petrosino S, Palazzo E, Rossi FS, Woodward DF, Di Marzo V. Analgesic actions of N-arachidonoyl-serotonin, a fatty acid amide hydrolase inhibitor with antagonistic activity at vanilloid TRPV1 receptors. Br J Pharmacol 2007; 150:766-81. [PMID: 17279090 PMCID: PMC2013858 DOI: 10.1038/sj.bjp.0707145] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND AND PURPOSE N-arachidonoyl-serotonin (AA-5-HT) is an inhibitor of fatty acid amide hydrolase (FAAH)-catalysed hydrolysis of the endocannabinoid/ endovanilloid compound, anandamide (AEA). We investigated if AA-5-HT antagonizes the transient receptor potential vanilloid-1 (TRPV1) channel and, as FAAH and TRPV1 are targets for analgesic compounds, if it exerts analgesia in rodent models of hyperalgesia. EXPERIMENTAL APPROACH AA-5-HT was tested in vitro, on HEK-293 cells overexpressing the human or the rat recombinant TRPV1 receptor, and in vivo, in rats and mice treated with formalin and in rats with chronic constriction injury of the sciatic nerve. The levels of the endocannabinoids, AEA and 2-arachidonoylglycerol, in supraspinal (periaqueductal grey, rostral ventromedial medulla), spinal or peripheral (skin) tissues were measured. KEY RESULTS AA-5-HT behaved as an antagonist at both rat and human TRPV1 receptors (IC(50)=37-40 nM against 100 nM capsaicin). It exerted strong analgesic activity in all pain models used here. This activity was partly due to FAAH inhibition, elevation of AEA tissue levels and indirect activation of cannabinoid CB(1) receptors, as it was reversed by AM251, a CB(1) antagonist. AA-5-HT also appeared to act either via activation/desensitization of TRPV1, following elevation of AEA, or as a direct TRPV1 antagonist, as suggested by the fact that its effects were either reversed by capsazepine and 5'-iodo-resiniferatoxin, two TRPV1 antagonists, or mimicked by these compounds administered alone. CONCLUSIONS AND IMPLICATIONS Possibly due to its dual activity as a FAAH inhibitor and TRPV1 antagonist, AA-5-HT was highly effective against both acute and chronic peripheral pain.
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Affiliation(s)
- S Maione
- Department of Experimental Medicine – Section of Pharmacology ‘L Donatelli', Second University of Naples Naples, Italy
| | - L De Petrocellis
- Endocannabinoid Research Group, Institute of Cybernetics ‘E Caianiello' CNR, Pozzuoli (Naples), Italy
| | - V de Novellis
- Department of Experimental Medicine – Section of Pharmacology ‘L Donatelli', Second University of Naples Naples, Italy
| | - A Schiano Moriello
- Endocannabinoid Research Group, Institute of Cybernetics ‘E Caianiello' CNR, Pozzuoli (Naples), Italy
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry CNR, Pozzuoli (Naples), Italy
| | - S Petrosino
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry CNR, Pozzuoli (Naples), Italy
- Department of Pharmaceutical Sciences, University of Salerno Fisciano, Italy
| | - E Palazzo
- Department of Experimental Medicine – Section of Pharmacology ‘L Donatelli', Second University of Naples Naples, Italy
| | - F Sca Rossi
- Department of Experimental Medicine – Section of Pharmacology ‘L Donatelli', Second University of Naples Naples, Italy
| | | | - V Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry CNR, Pozzuoli (Naples), Italy
- Author for correspondence:
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Ho WSV, Hillard CJ. Modulators of endocannabinoid enzymic hydrolysis and membrane transport. Handb Exp Pharmacol 2005:187-207. [PMID: 16596775 DOI: 10.1007/3-540-26573-2_6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Tissue concentrations of the endocannabinoids N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG) are regulated by both synthesis and inactivation. The purpose of this review is to compile available data regarding three inactivation processes: fatty acid amide hydrolase, monoacylglycerol lipase, and cellular membrane transport. In particular, we have focused on mechanisms by which these processes are modulated. We describe the in vitro and in vivo effects of inhibitors of these processes as well as available evidence regarding their modulation by other factors.
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Affiliation(s)
- W S V Ho
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
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Lambert DM, Fowler CJ. The Endocannabinoid System: Drug Targets, Lead Compounds, and Potential Therapeutic Applications. J Med Chem 2005; 48:5059-87. [PMID: 16078824 DOI: 10.1021/jm058183t] [Citation(s) in RCA: 256] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Didier M Lambert
- Unité de Chimie Pharmaceutique et de Radiopharmacie, Université Catholique de Louvain, 73 Avenue Mounier, UCL-CMFA 73.40, B-1200 Brussels, Belgium.
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26
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Holt S, Rocksén D, Bucht A, Petersen G, Hansen HS, Valenti M, Di Marzo V, Fowler CJ. Lipopolysaccharide-induced pulmonary inflammation is not accompanied by a release of anandamide into the lavage fluid or a down-regulation of the activity of fatty acid amide hydrolase. Life Sci 2004; 76:461-72. [PMID: 15530507 DOI: 10.1016/j.lfs.2004.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2004] [Accepted: 08/31/2004] [Indexed: 01/19/2023]
Abstract
The effect of lipopolysaccharide inhalation upon lung anandamide levels, anandamide synthetic enzymes and fatty acid amide hydrolase has been investigated. Lipopolysaccharide exposure produced a dramatic extravasation of neutrophils and release of tumour necrosis factor alpha into the bronchoalveolar lavage (BAL) fluid, which was not accompanied by epithelial cell injury. The treatment, however, did not change significantly the levels of anandamide and the related compound palmitoylethanolamide in the cell-free fraction of the BAL fluid. The activities of the anandamide synthetic enzymes N-acyltransferase and N-acylphosphatidylethanolamine phospholipase D and the activity of fatty acid amide hydrolase in lung membrane fractions did not change significantly following the exposure to lipopolysaccharide. The non-selective fatty acid amide hydrolase inhibitor phenylmethylsulfonyl fluoride was a less potent inhibitor of lung fatty acid amide hydrolase than expected from the literature, and a dose of 30 mg/kg i.p. of this compound, which produced a complete inhibition of brain anandamide metabolism, only partially inhibited the lung metabolic activity.
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Affiliation(s)
- Sandra Holt
- Department of Pharmacology and Clinical Neuroscience, Umeå University, SE901 87 Umeå, Sweden.
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Fowler CJ, Tiger G, Ligresti A, López-Rodríguez ML, Di Marzo V. Selective inhibition of anandamide cellular uptake versus enzymatic hydrolysis—a difficult issue to handle. Eur J Pharmacol 2004; 492:1-11. [PMID: 15145699 DOI: 10.1016/j.ejphar.2004.03.048] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2003] [Revised: 02/04/2004] [Accepted: 03/25/2004] [Indexed: 10/26/2022]
Abstract
There is considerable debate at present as to whether the uptake of anandamide (AEA) into cells is by a facilitated transport process or by passive diffusion driven by fatty acid amide hydrolase (FAAH). The possibility that both processes occur, but to different extents depending upon the cell type used, has been difficult to investigate pharmacologically since available compounds show little selectivity between inhibition of AEA uptake and inhibition of FAAH. Recently, three compounds, UCM707 [N-(Fur-3-ylmethyl)arachidonamide], OMDM-1 and OMDM-2 [the 1'-(S)- and 1'-(R)-enantiomers of the 1'-4-hydroxybenzoyl analogue of oleoylethanolamide], selective for the uptake process, have been described and we have used these compounds, together with AM404 [(N-(4-hydroxyphenyl) arachidonoyl amide)] and VDM11 [(5Z,8Z,11Z,14Z)-N-(4-Hydroxy-2-methylphenyl)-5,8,11,14-eicosatetraenamide]), with the initial aim of determining which mechanism of uptake predominates in C6 glioma and RBL-2H3 cells. AM404 and VDM11 were both found to decrease the uptake of 2 microM AEA into cells (IC50 values 6-11 microM), but they also inhibited rat brain FAAH (IC50 values 1-6 microM). However, when using a different FAAH assay protocol, VDM11 was a much less potent FAAH inhibitor (IC50>50 microM) regardless of the cell type and animal species used. In contrast, we confirmed that UCM707, OMDM-1 and OMDM-2 were weak inhibitors of FAAH (IC50 values >50 microM) under all conditions used. However, their potency as inhibitors of AEA cellular accumulation appears to be largely dependent on the cell type and assay conditions used. In particular, the potency of UCM707 (IC50 value > or =25 microM) was considerably lower than the submicromolar potency previously reported for U937 cells. It is concluded that the cause/effect relationship between AEA uptake and hydrolysis cannot be investigated uniquely by using supposedly selective inhibitors of each process.
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Affiliation(s)
- Christopher J Fowler
- Department of Pharmacology and Clinical Neuroscience, Umeå University, SE-901 87 Umeå, Sweden.
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28
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Wilson SJ, Lovenberg TW, Barbier AJ. A high-throughput-compatible assay for determining the activity of fatty acid amide hydrolase. Anal Biochem 2003; 318:270-5. [PMID: 12814631 DOI: 10.1016/s0003-2697(03)00217-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Fatty acid amide hydrolase (EC 3.5.1.4.) is the enzyme responsible for the rapid degradation of lipid-derived chemical messengers such as anandamide, oleamide, and 2-arachidonoylglycerol. The pharmacological characterization of this enzyme in vivo has been hampered by the lack of selective and bioavailable inhibitors. We have developed a simple, radioactive, high-throughput-compatible assay for this enzyme based on the differential absorption of the substrate and its products to activated charcoal. The assay was validated using known inhibitors. It may be applied for the identification of new inhibitors from a compound library.
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Affiliation(s)
- Sandy J Wilson
- Johnson & Johnson Pharmaceutical Research & Development LLC Neuroscience, 3210 Merryfield Row, San Diego, CA 92121, USA
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Vandevoorde S, Jonsson KO, Fowler CJ, Lambert DM. Modifications of the ethanolamine head in N-palmitoylethanolamine: synthesis and evaluation of new agents interfering with the metabolism of anandamide. J Med Chem 2003; 46:1440-8. [PMID: 12672243 DOI: 10.1021/jm0209679] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The endogenous fatty acid amide anandamide (AEA) has, as a result of its actions on cannabinoid and vanilloid receptors, a number of important pharmacological properties including effects on nociception, memory processes, spasticity, and cell proliferation. Inhibition of the metabolism of AEA, catalyzed by fatty acid amide hydrolase (FAAH), potentiates the actions of AEA in vivo and therefore may be a useful target for drug development. In the present study, we have investigated whether substitution of the headgroup of the endogenous alternative FAAH substrate palmitoylethanolamide (PEA) can result in the identification of novel compounds preventing AEA metabolism. Thirty-seven derivatives of PEA were synthesized, with the C16 long chain of palmitic acid kept intact, and comprising 20 alkylated, 12 aromatic, and 4 halogenated amides. The ability of the PEA derivatives to inhibit FAAH-catalyzed hydrolysis of [(3)H]AEA was investigated using rat brain homogenates as a source of FAAH. Inhibition curves were analyzed to determine the potency of the inhibitable fraction (pI(50) values) and the maximal attained inhibition for the compound, given that solubility in an aqueous environment is a major issue for these compounds. In the alkylamide family, palmitoylethylamide and palmitoylallylamide were inhibitors of AEA metabolism with pI(50) values of 5.45 and 5.47, respectively. Halogenated derivatives (Cl and Br) exhibit pI(50) values of approximately 5.5 but rather low percentages of maximal inhibition. The -OH group of the ethyl head chain of N-palmitoylethanolamine was not necessary for interaction with FAAH. Amides containing aromatic moieties were less potent inhibitors of AEA metabolism. Compounds containing amide and ester bonds, 13 and 37, showed pI(50) values of 4.99 and 5.08, respectively. None of the compounds showed obvious affinity for CB(1) or CB(2) receptors expressed on Chinese hamster ovary (CHO) cells. It is concluded that although none of the compounds were dramatically more potent than PEA itself at reducing the metabolism of AEA, the lack of effect of the compounds at CB(1) and CB(2) receptors makes them useful templates for development of possible therapeutic FAAH inhibitors.
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Affiliation(s)
- Séverine Vandevoorde
- Unité de Chimie Pharmaceutique et de Radiopharmacie, Université Catholique de Louvain, Avenue Mounier, 73, UCL-CMFA 73.40, B-1200 Brussels, Belgium
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Holt S, Fowler CJ. Anandamide metabolism by fatty acid amide hydrolase in intact C6 glioma cells. Increased sensitivity to inhibition by ibuprofen and flurbiprofen upon reduction of extra- but not intracellular pH. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2003; 367:237-44. [PMID: 12644895 DOI: 10.1007/s00210-002-0686-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2002] [Accepted: 11/26/2002] [Indexed: 10/25/2022]
Abstract
The metabolism of anandamide by fatty acid amidohydrolase (FAAH) at different intra- and extracellular pH values has been investigated in intact C6 rat glioma cells. The cellular uptake of anandamide at 37 degrees C was found to decrease by 28% when the extracellular pH (pH(e)) was reduced from pH 7.4 to pH 6.2. In contrast, a selective decrease in intracellular pH (pH(i)), accomplished by acidifying the cells followed by incubation in sodium-free buffer at pH 7.4, did not affect the uptake. Anandamide uptake was inhibited by (R)-ibuprofen, with pI(50) values of 3.05+/-0.57, 3.66+/-0.23 and 3.94+/-0.88 at pH(e) values of 7.4, 6.8 and 6.2, respectively. In the presence of phenylmethylsulfonyl fluoride, however, (R)-ibuprofen failed to inhibit the uptake of anandamide. A reduction in pH(e) from 7.4 to 6.2 produced a 17% reduction in the FAAH-catalyzed metabolism of anandamide in the intact C6 cells. However, an increased sensitivity of FAAH activity to inhibition by (R)-ibuprofen as well as (R,S)-flurbiprofen and (S)-flurbiprofen was seen at a lower pH(e). For (R)-ibuprofen, pI(50) values of 3.57+/-0.08, 4.04+/-0.05 and 4.59+/-0.04 were found at pH(e) values of 7.4, 6.8 and 6.2, respectively. For (R,S)- and (S)-flurbiprofen, the pI(50) values at pH(e) 7.4 were 4.02+/-0.05 and 4.13+/-0.18, respectively at a pH(e) of 7.4, and 4.81+/-0.11 and 4.84+/-0.10, respectively, at a pH(e) of 6.2. In contrast, intracellular acidification did not affect either the rate of anandamide metabolism or its inhibition by (R)-ibuprofen or (S)-flurbiprofen. It is concluded that a reduction of extracellular pH produces an enhanced accumulation of the acidic NSAIDs ibuprofen and flurbiprofen into C6 glioma cells and thereby an inhibition of anandamide metabolism.
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Affiliation(s)
- Sandra Holt
- Department of Pharmacology and Clinical Neuroscience, Umeå University, 901 87 Umeå, Sweden.
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Ross RA, Craib SJ, Stevenson LA, Pertwee RG, Henderson A, Toole J, Ellington HC. Pharmacological characterization of the anandamide cyclooxygenase metabolite: prostaglandin E2 ethanolamide. J Pharmacol Exp Ther 2002; 301:900-7. [PMID: 12023517 DOI: 10.1124/jpet.301.3.900] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Anandamide can be metabolized by cyclooxygenase-2 to produce prostaglandin E(2) (PGE(2)) ethanolamide. The purpose of this study was to investigate the pharmacology of this novel compound. Radioligand binding experiments in membranes from human embryonic kidney cells transfected with PGE(2) receptor subtypes EP(1), EP(2), EP(3), and EP(4) revealed that PGE(2) ethanolamide has pK(i) values of 5.61 +/- 0.1, 6.33 +/- 0.01, 6.70 +/- 0.13, and 6.29 +/- 0.06, respectively, compared with 8.31 +/- 0.16, 9.03 +/- 0.04, 9.34 +/- 0.06, and 9.10 +/- 0.04 for PGE(2). PGE(2) inhibits electrically evoked contractions of the guinea pig vas deferens (EP(3) receptor-mediated), with a pEC(50) value of 9.09 +/- 0.06, compared with that of 7.38 +/- 0.09 for PGE(2) ethanolamide. In the guinea pig trachea, 100 nM PGE(2) and 1 microM PGE(2) ethanolamide produced contractions of 51.8 +/- 10.6 and 38.9 +/- 5.6% (of the histamine E(max)), respectively. The EP(1) receptor antagonist SC-51089 (10 microM) prevented the contractions induced by both compounds. In the presence of 10 microM 8-chlorodibenz[b,f][1,4]oxazepine-10(11H)-carboxylic acid, 2-[1-oxo-3-(4-pyridinyl)propyl]hydrazide, monohydrochloride (SC-51089), PGE(2) caused a concentration-related relaxation of histamine-induced contractions of this tissue (EP(2) receptor-mediated), the pEC(50) value being 8.29 +/- 0.17 compared with that of 7.11 +/- 0.18 for PGE(2) ethanolamide. In the rabbit jugular vein, PGE(2) induces relaxation (EP(4) receptor-mediated) with a pEC(50) of 9.35 +/- 0.25, compared with 7.05 +/- 0.4 for PGE(2) ethanolamide. In dorsal root ganglion neurons in culture, 3 microM PGE(2) ethanolamide evoked an increase in intracellular calcium concentration in 21% of small-diameter capsaicin-sensitive neurons. We conclude that this compound is pharmacologically active, however its physiological relevance has yet to be established.
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Affiliation(s)
- Ruth A Ross
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, UK AB25 2ZD.
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