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Breslin HJ, Diamond CJ, Kavash RW, Cai C, Dyatkin AB, Miskowski TA, Zhang SP, Wade PR, Hornby PJ, He W. Identification of a dual δ OR antagonist/μ OR agonist as a potential therapeutic for diarrhea-predominant Irritable Bowel Syndrome (IBS-d). Bioorg Med Chem Lett 2012; 22:4869-72. [DOI: 10.1016/j.bmcl.2012.05.042] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 05/04/2012] [Accepted: 05/08/2012] [Indexed: 10/28/2022]
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102
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Parenti C, Turnaturi R, Aricò G, Marrazzo A, Prezzavento O, Ronsisvalle S, Scoto GM, Ronsisvalle G, Pasquinucci L. Antinociceptive profile of LP1, a non-peptide multitarget opioid ligand. Life Sci 2012; 90:957-61. [PMID: 22580287 DOI: 10.1016/j.lfs.2012.04.041] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 04/20/2012] [Accepted: 04/24/2012] [Indexed: 10/28/2022]
Abstract
AIMS Opioid drugs are the principal treatment option for moderate to severe pain and exert their biological effects through interactions with opioid receptors that are widely distributed throughout the CNS and peripheral tissues. Ligands capable of simultaneously targeting different receptors could be successful candidates for the treatment of chronic pain. Enhanced antinociception coupled with a low incidence of side effects has been demonstrated for ligands possessing mixed mu-opioid receptor (MOR) and delta-opioid receptor (DOR) activity. We previously reported that 3-[(2R,6R,11R)-8-hydroxy-6,11-dimethyl-1,4,5,6-tetrahydro-2,6-methano-3-benzazocin-3(2H)-yl]-N-phenylpropanamide (LP1) acted as a MOR-DOR ligand in in vitro functional assays and moreover this drug produced a valid antinociception that was longer lasting than that of morphine. The aim of this work was to determine whether the antinociceptive effect produced by LP1 was central or peripheral and to assess which opioid receptor subtypes are involved in its effects. MAIN METHODS We explored the effects of naloxone methiodide (NX-M), a quaternary opioid antagonist, administered either intracerebroventricularly (i.c.v.) or subcutaneously (s.c.), on LP1-mediated antinociception in male Sprague-Dawley rats. In addition, we administered s.c. selective antagonists for MOR, DOR and kappa-opioid receptor (KOR) to investigate the effects of LP1. To characterise this drug's DOR profile better, we also investigated the effects of LP1 on DPDPE, a selective DOR agonist. KEY FINDINGS Data obtained by tail flick test showed that LP1 induced predominantly MOR-mediated supraspinal antinociception and was able to counteract DPDPE analgesia. SIGNIFICANCE LP1, a multitarget opioid ligand, is a supraspinal acting antinociceptive agent that is useful for the treatment of chronic pain.
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Affiliation(s)
- Carmela Parenti
- Department of Drug Sciences, Pharmacology and Toxicology section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
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Moppett IK. Measuring academic productivity. Anaesthesia 2012; 67:185; author reply 185-6. [DOI: 10.1111/j.1365-2044.2011.07030_1.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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104
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Guillemyn K, Kleczkowska P, Novoa A, Vandormael B, Van den Eynde I, Kosson P, Asim MF, Schiller PW, Spetea M, Lipkowski AW, Tourwé D, Ballet S. In vivo antinociception of potent mu opioid agonist tetrapeptide analogues and comparison with a compact opioid agonist-neurokinin 1 receptor antagonist chimera. Mol Brain 2012; 5:4. [PMID: 22289619 PMCID: PMC3284447 DOI: 10.1186/1756-6606-5-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 01/30/2012] [Indexed: 11/15/2022] Open
Abstract
Background An important limiting factor in the development of centrally acting pharmaceuticals is the blood-brain barrier (BBB). Transport of therapeutic peptides through this highly protective physiological barrier remains a challenge for peptide drug delivery into the central nervous system (CNS). Because the most common strategy to treat moderate to severe pain consists of the activation of opioid receptors in the brain, the development of active opioid peptide analogues as potential analgesics requires compounds with a high resistance to enzymatic degradation and an ability to cross the BBB. Results Herein we report that tetrapeptide analogues of the type H-Dmt1-Xxx2-Yyy3-Gly4-NH2 are transported into the brain after intravenous and subcutaneous administration and are able to activate the μ- and δ opioid receptors more efficiently and over longer periods of time than morphine. Using the hot water tail flick test as the animal model for antinociception, a comparison in potency is presented between a side chain conformationally constrained analogue containing the benzazepine ring (BVD03, Yyy3: Aba), and a "ring opened" analogue (BVD02, Yyy3: Phe). The results show that in addition to the increased lipophilicity through amide bond N-methylation, the conformational constraint introduced at the level of the Phe3 side chain causes a prolonged antinociception. Further replacement of NMe-D-Ala2 by D-Arg2 in the tetrapeptide sequence led to an improved potency as demonstrated by a higher and maintained antinociception for AN81 (Xxx2: D-Arg) vs. BVD03 (Xxx2: NMe-D-Ala). A daily injection of the studied opioid ligands over a time period of 5 days did however result in a substantial decrease in antinociception on the fifth day of the experiment. The compact opioid agonist - NK1 antagonist hybrid SBCHM01 could not circumvent opioid induced tolerance. Conclusions We demonstrated that the introduction of a conformational constraint has an important impact on opioid receptor activation and subsequent antinociception in vivo. Further amino acid substitution allowed to identify AN81 as an opioid ligand able to access the CNS and induce antinociception at very low doses (0.1 mg/kg) over a time period up to 7 hours. However, tolerance became apparent after repetitive i.v. administration of the investigated tetrapeptides. This side effect was also observed with the dual opioid agonist-NK1 receptor antagonist SBCHM01.
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Affiliation(s)
- Karel Guillemyn
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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Cardinale F, Mastrototaro MF, Cappiello A, Caffarelli C, Caimmi S, Barberi S, Bernardini R. Immunological modifications induced from products used during the perioperative period. Int J Immunopathol Pharmacol 2012; 24:S13-20. [PMID: 22014921 DOI: 10.1177/03946320110240s303] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Anesthetics and other products used during the perioperative period may influence immune function not only merely by reducing the HPA-axis stress response but also by directly modulating innate and adaptive immune responses. Most of the literature on the immune effects of anesthetics has been derived from in vitro or animal studies, due to the number of confounding variables in real life surgical settings. These immunosuppressive effects might not normally have clinical consequences for an immune-competent patient, but may act as important modifiers in postoperative morbidity and mortality. Furthermore, some inhibitory effects on neutrophil functions may provide a therapeutically beneficial effect under specific surgical clinical conditions, such as ischemia-reperfusion injury.
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Affiliation(s)
- F Cardinale
- Department of Allergy and Pulmonology, Pediatric Hospital Giovanni XXIII, University of Bari, Bari, Italy.
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106
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Dietis N, McDonald J, Molinari S, Calo G, Guerrini R, Rowbotham DJ, Lambert DG. Pharmacological characterization of the bifunctional opioid ligand H-Dmt-Tic-Gly-NH-Bzl (UFP-505). Br J Anaesth 2011; 108:262-70. [PMID: 22194444 DOI: 10.1093/bja/aer377] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND While producing good-quality analgesia, µ-opioid (MOP) receptor activation produces a number of side-effects including tolerance. Simultaneous blockade of δ-opioid (DOP) receptors has been shown to reduce tolerance to morphine. Here, we characterize a prototype bifunctional opioid H-Dmt-Tic-Gly-NH-Bzl (UFP-505). METHODS We measured receptor binding affinity in Chinese hamster ovary (CHO) cells expressing recombinant human MOP, DOP, k-opioid (KOP), nociceptin/orphanin (NOP) receptors. For activation, we measured the binding of GTPγ(35)S to membranes from CHO(hMOP), CHO(hDOP), rat cerebrocortex, and rat spinal cord. In addition, we assessed 'end organ' responses in the guinea pig ileum and mouse vas deferens. RESULTS UFP-505 bound to CHO(hMOP) and CHO(hDOP) with (binding affinity) pK(i) values of 7.79 and 9.82, respectively. There was a weak interaction at KOP and NOP (pK(i) 6.29 and 5.86). At CHO(hMOP), UFP-505 stimulated GTPγ(35)S binding with potency (pEC(50)) of 6.37 and in CHO(hDOP) reversed the effects of a DOP agonist with affinity (pK(b)) of 9.81 (in agreement with pK(i) at DOP). UFP-505 also stimulated GTPγ(35)S binding in rat cerebrocortex and spinal cord with pEC(50) values of 6.11-6.53. In the guinea pig ileum (MOP-rich preparation), UFP-505 inhibited contractility with pEC(50) of 7.50 and in the vas deferens (DOP-rich preparation) reversed the effects of a DOP agonist with an affinity (pA(2)) of 9.15. CONCLUSIONS We have shown in a range of preparations and assays that UFP-505 behaves as a potent MOP agonist and DOP antagonist; a MOP/DOP bifunctional opioid. Further studies in dual expression systems and whole animals with this prototype are warranted.
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Affiliation(s)
- N Dietis
- Department of Cardiovascular Sciences, University of Leicester, Leicester Royal Infirmary, Leicester LE1 5WW, UK.
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Brissett DI, Whistler JL, van Rijn RM. Contribution of mu and delta opioid receptors to the pharmacological profile of kappa opioid receptor subtypes. Eur J Pain 2011; 16:327-37. [PMID: 22337177 DOI: 10.1002/j.1532-2149.2011.00022.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2011] [Indexed: 12/12/2022]
Abstract
Molecular cloning has identified three opioid receptors: mu (MOR), delta (DOR) and kappa (KOR). Yet, cloning of these receptor types has offered little clarification to the diverse pharmacological profiles seen within the growing number of novel opioid ligands, which has led to the proposal of multiple subtypes. In the present study, utilizing in vitro and in vivo methods including the use of opioid receptor knockout mice, we find that certain antinociceptive effects of the KOR-1 and KOR-2 subtype-selective ligands (+)-(5α,7α,8β)-N-Methyl-N-[7-(1-pyrrolidinyl)-1-oxaspiro[4.5]dec-8-yl]-benzene-acetamide (U69, 593) and 4-[(3,4-Dichlorophenyl)acetyl]-3-(1-pyrrolidinylmethyl)-1-piperazine-carboxylic acid methyl ester fumarate (GR89, 696), respectively, are potentiated by antagonism of MOR and DOR receptors. We believe that our findings can be best explained by the existence of KOR-DOR and KOR-MOR heteromers. We only find evidence for the existence of these heteromers in neurons mediating mechanical nociception, but not thermal nociception. These findings have important clinical ramifications as they reveal new drug targets that may provide avenues for more effective pain therapies.
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Affiliation(s)
- D I Brissett
- Ernest Gallo Clinic and Research Center, Department of Neurology, University of California, San Francisco, Emeryville, CA 94608, USA
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Pasquinucci L, Parenti C, Turnaturi R, Aricò G, Marrazzo A, Prezzavento O, Ronsisvalle S, Georgoussi Z, Fourla DD, Scoto GM, Ronsisvalle G. The benzomorphan-based LP1 ligand is a suitable MOR/DOR agonist for chronic pain treatment. Life Sci 2011; 90:66-70. [PMID: 22100511 DOI: 10.1016/j.lfs.2011.10.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 09/05/2011] [Accepted: 10/08/2011] [Indexed: 10/15/2022]
Abstract
AIMS Powerful analgesics relieve pain primarily through activating mu opioid receptor (MOR), but the long-term use of MOR agonists, such as morphine, is limited by the rapid development of tolerance. Recently, it has been observed that simultaneous stimulation of the delta opioid receptor (DOR) and MOR limits the incidence of tolerance induced by MOR agonists. 3-[(2R,6R,11R)-8-hydroxy-6,11-dimethyl-1,4,5,6-tetrahydro-2,6-methano-3-benzazocin-3(2H)-yl]-N-phenylpropanamide (LP1) is a centrally acting agent with antinociceptive activity comparable to morphine and is able to bind and activate MOR and DOR. The aim of this work was to evaluate and compare the induction of tolerance to antinociceptive effects from treatment with LP1 and morphine. MAIN METHODS Here, we evaluated the pharmacological effects of LP1 administered at a dose of 4 mg/kg subcutaneously (s.c.) twice per day for 9 days to male Sprague-Dawley rats. In addition, the LP1 mechanism of action was assessed by measurement of LP1-induced [(35)S]GTPγS binding to the MOR and DOR. KEY FINDINGS Data obtained from the radiant heat tail flick test showed that LP1 maintained its antinociceptive profile until the ninth day, while tolerance to morphine (10mg/kg s.c. twice per day) was observed on day 3. Moreover, LP1 significantly enhanced [(35)S]GTPγS binding in the membranes of HEK293 cells expressing either the MOR or the DOR. SIGNIFICANCE LP1 is a novel analgesic agent for chronic pain treatment, and its low tolerance-inducing capability may be correlated with its ability to bind both the MOR and DOR.
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Affiliation(s)
- Lorella Pasquinucci
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy.
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109
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Proceedings of the Anaesthetic Research Society. Br J Anaesth 2011. [DOI: 10.1093/bja/aer234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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110
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Hales T. Arresting the development of morphine tolerance and dependence. Br J Anaesth 2011; 107:653-5. [DOI: 10.1093/bja/aer294] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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111
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Yang CH, Huang HW, Chen KH, Chen YS, Sheen-Chen SM, Lin CR. Antinociceptive potentiation and attenuation of tolerance by intrathecal β-arrestin 2 small interfering RNA in rats. Br J Anaesth 2011; 107:774-81. [PMID: 21926413 DOI: 10.1093/bja/aer291] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Tolerance to the analgesic effect of opioids complicates the management of persistent pain states. We tested whether the intrathecal infusion of small interfering RNA (siRNA) against β-arrestin 2 would reduce tolerance to chronic morphine use and the severity of precipitated morphine withdrawal. METHODS Intrathecal β-arrestin 2 (2 μg siRNA per 10 μl per rat) was injected once daily for 3 days. Rats then received a continuous intrathecal infusion of morphine (2 nmol h⁻¹) or saline for 7 days. Daily tail-flick (TF) and intrathecal morphine challenge tests were performed to assess the effect of intrathecal β-arrestin 2 siRNA on antinociception and tolerance to morphine. Naloxone withdrawal (2 mg kg⁻¹) was performed to assess morphine dependence. RESULTS In the daily TF test, the antinociception of intrathecal morphine was increased and maintained in rats receiving β-arrestin 2 siRNA compared with the control group (morphine alone). In the probe response test, rats receiving morphine infusion with β-arrestin 2 siRNA treatment showed a significant left shift in their dose-response curve, as measured by per cent maximal possible effect (MPE), such that the AD₅₀ was significantly decreased by a factor of 5.6 when compared with that of morphine-infused rats. In the naloxone-induced withdrawal tests, rats receiving β-arrestin 2 siRNA injection with morphine infusion showed a significant reduction in four of the six signs of withdrawal. CONCLUSIONS We show here that intrathecal β-arrestin 2 siRNA in rats enhances analgesia and attenuates naloxone-induced withdrawal symptoms. This may warrant further investigation in the context of long-term use of intrathecal opioids for controlling chronic pain.
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Affiliation(s)
- C-H Yang
- Department of Anesthesiology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Niao-Sung District, Kaohsiung, Taiwan
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113
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Banks ML, Roma PG, Folk JE, Rice KC, Negus SS. Effects of the delta-opioid agonist SNC80 on the abuse liability of methadone in rhesus monkeys: a behavioral economic analysis. Psychopharmacology (Berl) 2011; 216:431-9. [PMID: 21369752 PMCID: PMC3557963 DOI: 10.1007/s00213-011-2235-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 02/16/2011] [Indexed: 11/28/2022]
Abstract
RATIONALE Delta-opioid agonists enhance the antinociceptive efficacy of methadone and other mu-opioid agonists. However, relatively little is known about the degree to which delta agonists might enhance the abuse-related effects of mu agonists. OBJECTIVE This study used a behavioral economic approach to examine effects of the delta agonist SNC80 [(+)-4-[(αR)-α-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide] on the reinforcing effects of methadone in a drug self-administration assay. Interactions between SNC80 and cocaine were also examined for comparison. METHODS Rhesus monkeys (n = 4), surgically implanted with indwelling intravenous catheters, were tested in two phases. In phase 1, drug self-administration dose-effect curves for methadone (0.0032-0.1 mg/kg/injection (inj)) and cocaine (0.0032-0.32 mg/kg/inj) alone were determined under a fixed-ratio 10 (FR 10) schedule of reinforcement. In phase 2, FR values were increased every 3 days (FR 1-FR 1800) during availability of methadone alone (0.032 mg/kg/inj) and in combination with varying proportions of SNC80 (0.1:1, 0.3:1, and 0.9:1 SNC80/methadone) or of cocaine alone (0.032 mg/kg/inj) and in combination with varying proportions of SNC80 (0.33:1, 1:1, and 3:1 SNC80/cocaine). Demand curves related drug intake to FR price, and measures of reinforcement were derived. RESULTS Methadone and cocaine alone each functioned as a reinforcer. SNC80 did not alter measures of reinforcement for either methadone or cocaine. CONCLUSIONS SNC80 at proportions previously shown to enhance methadone-induced antinociception did not enhance the abuse-related effects of methadone. These results support the proposition that delta agonists may selectively enhance mu agonist analgesic effects without enhancing mu agonist abuse liability.
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Affiliation(s)
- Matthew L. Banks
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 North 12th Street, PO Box 980613, Richmond, VA 23298, USA
| | - Peter G. Roma
- Institute for Behavior Resources, Baltimore, MD, USA. Department of Psychiatry and Behavioral Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - John E. Folk
- Chemical Biology Research Branch, National Institute on Drug Abuse, National Institutes of Health, DHHS, Bethesda, MD, USA
| | - Kenner C. Rice
- Chemical Biology Research Branch, National Institute on Drug Abuse, National Institutes of Health, DHHS, Bethesda, MD, USA
| | - S. Stevens Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 North 12th Street, PO Box 980613, Richmond, VA 23298, USA
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Yuan P, Liang K, Ma B, Zheng N, Nussinov R, Huang J. Multiple-targeting and conformational selection in the estrogen receptor: computation and experiment. Chem Biol Drug Des 2011; 78:137-49. [PMID: 21443691 PMCID: PMC3115459 DOI: 10.1111/j.1747-0285.2011.01119.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Conformational selection is a primary mechanism in biomolecular recognition. The conformational ensemble may determine the ability of a drug to compete with a native ligand for a receptor target. Traditional docking procedures which use one or few protein structures are limited and may not be able to represent a complex competition among closely related protein receptors in agonist and antagonist ensembles. Here, we test a protocol aimed at selecting a drug candidate based on its ability to synergistically bind to distinct conformational states. We demonstrate, for the case of estrogen receptor α (ERα) and estrogen receptor β (ERβ), that the functional outcome of ligand binding can be inferred from its ability to simultaneously bind both ERα and ERβ in agonist and antagonist conformations as calculated docking scores. Combining a conformational selection method with an experimental reporter gene system in yeast, we propose that several phytoestrogens can be novel estrogen receptor β selective agonists. Our work proposes a computational protocol to select estrogen receptor subtype selective agonists. Compared with other models, present method gives the best prediction in ligands' function.
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Affiliation(s)
- Peng Yuan
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, Hubei, China
| | - Kaiwei Liang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, Hubei, China
| | - Buyong Ma
- Center for Cancer Research Nanobiology Program, SAIC-Frederick, National Cancer Institute, Frederick, MD 21702,USA
| | - Nan Zheng
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, Hubei, China
| | - Ruth Nussinov
- Center for Cancer Research Nanobiology Program, SAIC-Frederick, National Cancer Institute, Frederick, MD 21702,USA
- Department of Human Genetics and Molecular Medicine, Sackler Institute of Molecular Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jian Huang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, Hubei, China
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Abstract
Twin and triplet drugs are defined as compounds that contain respectively two and three pharmacophore components exerting pharmacological effects in a molecule. The twin drug bearing the same pharmacophores is a "symmetrical twin drug", whereas that possessing different pharmacophores is a "nonsymmetrical twin drug." In general, the symmetrical twin drug is expected to produce more potent and/or selective pharmacological effects, whereas the nonsymmetrical twin drug is anticipated to show both pharmacological activities stemming from the individual pharmacophores (dual action). On the other hand, nonsymmetrical triplet drugs, which have two of the same pharmacophores and one different moiety, are expected to elicit both increased pharmacological action and dual action. The two identical portions could bind the same receptor sites simultaneously while the third portion could bind a different receptor site or enzyme. This review will mainly focus on the twin and triplet drugs with an evaluation of their in vivo pharmacological effects, and will also include a description of their pharmacology and synthesis.
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Affiliation(s)
- Hideaki Fujii
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan.
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116
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Dietis N, Rowbotham DJ, Lambert DG. Opioid receptor subtypes: fact or artifact? Br J Anaesth 2011; 107:8-18. [PMID: 21613279 DOI: 10.1093/bja/aer115] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
There is a vast amount of pharmacological evidence favouring the existence of multiple subtypes of opioid receptors. In addition to the primary classification of µ (mu: MOP), δ (delta: DOP), κ (kappa: KOP) receptors, and the nociceptin/orphanin FQ peptide receptor (NOP), various groups have further classified the pharmacological µ into µ(1-3), the δ into δ(1-2)/δ(complexed/non-complexed), and the κ into κ(1-3). From an anaesthetic perspective, the suggestions that µ(1) produced analgesia and µ(2) produced respiratory depression are particularly important. However, subsequent to the formal identification of the primary opioid receptors (MOP/DOP/KOP/NOP) by cloning and the use of this information to produce knockout animals, evidence for these additional subtypes is lacking. Indeed, knockout of a single gene (and hence receptor) results in a loss of all function associated with that receptor. In the case of MOP knockout, analgesia and respiratory depression is lost. This suggests that further sub-classification of the primary types is unwise. So how can the wealth of pharmacological data be reconciled with new molecular information? In addition to some simple misclassification (κ(3) is probably NOP), there are several possibilities which include: (i) alternate splicing of a common gene product, (ii) receptor dimerization, (iii) interaction of a common gene product with other receptors/signalling molecules, or (iv) a combination of (i)-(iii). Assigning variations in ligand activity (pharmacological subtypes) to one or more of these molecular suggestions represents an interesting challenge for future opioid research.
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Affiliation(s)
- N Dietis
- Department of Cardiovascular Sciences (Pharmacology and Therapeutics Group), Division of Anaesthesia, Critical Care and Pain Management, University of Leicester, Leicester Royal Infirmary, Leicester LE1 5WW, UK
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Wei LN, Loh HH. Transcriptional and epigenetic regulation of opioid receptor genes: present and future. Annu Rev Pharmacol Toxicol 2011; 51:75-97. [PMID: 20868272 DOI: 10.1146/annurev-pharmtox-010510-100605] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Three opioid receptors (ORs) are known: μ opioid receptors (MORs), δ opioid receptors (DORs), and κ opioid receptors (KORs). Each is encoded by a distinct gene, and the three OR genes share a highly conserved genomic structure and promoter features, including an absence of TATA boxes and sensitivity to extracellular stimuli and epigenetic regulation. However, each of the genes is differentially expressed. Transcriptional regulation engages both basal and regulated transcriptional machineries and employs activating and silencing mechanisms. In retinoic acid-induced neuronal differentiation, the opioid receptor genes undergo drastically different chromatin remodeling processes and display varied patterns of epigenetic marks. Regulation of KOR expression is distinctly complex, and KOR exerts a unique function in neurite extension, indicating that KOR is not simply a pharmacological cousin of MOR and DOR. As the expression of OR proteins is ultimately controlled by extensive posttranscriptional processing, the pharmacological implication of OR gene regulation at the transcriptional level remains to be determined.
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Affiliation(s)
- Li-Na Wei
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, 55455, USA.
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Del Giudice MR, Borioni A, Bastanzio G, Sbraccia M, Mustazza C, Sestili I. Synthesis and pharmacological evaluation of bivalent antagonists of the nociceptin opioid receptor. Eur J Med Chem 2011; 46:1207-21. [DOI: 10.1016/j.ejmech.2011.01.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 01/17/2011] [Accepted: 01/25/2011] [Indexed: 11/27/2022]
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McDonald J, Lambert DG. Opioid mechanisms and opioid drugs. ANAESTHESIA AND INTENSIVE CARE MEDICINE 2011. [DOI: 10.1016/j.mpaic.2010.10.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Chiurchiù V, Izzi V, D'Aquilio F, Vismara D, Carotenuto F, Catanzaro G, Maccarrone M. Endomorphin-1 prevents lipid accumulation via CD36 down-regulation and modulates cytokines release from human lipid-laden macrophages. Peptides 2011; 32:80-5. [PMID: 20932867 DOI: 10.1016/j.peptides.2010.09.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 09/24/2010] [Accepted: 09/24/2010] [Indexed: 12/21/2022]
Abstract
CD36 is a scavenger receptor known to play a critical role in the development of atherosclerosis by mediating the uptake of oxidized low-density lipoproteins (oxLDL) by macrophages, thus leading to foam cell formation. It is now generally recognized that the immune system has a pivotal role in the pathogenesis of atherosclerosis, whose progression is determined by ongoing inflammatory reactions. Recently, several studies pointed out that opioid peptides exert anti-inflammatory activities. Therefore the aim of the present study was to evaluate a possible endomorphin-1 (EM-1) immunomodulatory activity on human foam cells. Our results showed that EM-1 reduced Nile Red-stained lipid droplets content, decreased the expression of CD36 receptor and modulated tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) release from lipid-laden macrophages. Furthermore, Naloxone, an opioid receptors antagonist, reverted the anti-atherogenic and anti-inflammatory observed effects of EM-1. These data demonstrated, for the first time, an unprecedented ability of EM-1 to act as a novel modulator for macrophage-to-foam cell transformation, and for inflammatory cytokines profile, suggesting possible novel endomorphin-based anti-atherosclerotic approaches for the prevention and treatment of atherosclerosis.
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Affiliation(s)
- Valerio Chiurchiù
- Laboratory of Lipid Neurochemistry, European Center for Brain Research (CERC)/IRCCS Fondazione S.Lucia, Via del Fosso di Fiorano 65, 00143 Rome, Italy.
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121
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Balboni G, Salvadori S, Marczak ED, Knapp BI, Bidlack JM, Lazarus LH, Peng X, Si YG, Neumeyer JL. Opioid bifunctional ligands from morphine and the opioid pharmacophore Dmt-Tic. Eur J Med Chem 2010; 46:799-803. [PMID: 21216504 DOI: 10.1016/j.ejmech.2010.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 10/28/2010] [Accepted: 12/01/2010] [Indexed: 01/31/2023]
Abstract
Bifunctional ligands containing an ester linkage between morphine and the δ-selective pharmacophore Dmt-Tic were synthesized, and their binding affinity and functional bioactivity at the μ, δ and κ opioid receptors determined. Bifunctional ligands containing or not a spacer of β-alanine between the two pharmacophores lose the μ agonism deriving from morphine becoming partial μ agonists 4 or μ antagonists 5. Partial κ agonism is evidenced only for compound 4. Finally, both compounds showed potent δ antagonism.
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Affiliation(s)
- Gianfranco Balboni
- Department of Toxicology, University of Cagliari, Via Ospedale 72, I-09124 Cagliari, Italy.
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122
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Kumar K, Kumar S, Kurupati RK, Seth MK, Mohan A, Hussain ME, Pasha S. Intracellular cAMP assay and Eu-GTP-γS binding studies of chimeric opioid peptide YFa. Eur J Pharmacol 2010; 650:28-33. [PMID: 20887721 DOI: 10.1016/j.ejphar.2010.09.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 07/26/2010] [Accepted: 09/14/2010] [Indexed: 11/20/2022]
Abstract
In our previous studies chimeric peptide of Met-enkephalin and FMRFa, YGGFMKKKFMRFamide (YFa), demonstrated concentration dependent κ- and μ-opioid receptor mediated antinociception without tolerance development. To gain further insight of the observed behavior of YFa, the present study was undertaken. The effect of chimeric peptide on forskolin-stimulated cAMP formation under acute and chronic treatment and stimulation of Eu-GTP-γS binding in CHO cells stably expressing κ- and μ-opioid receptors was assessed. YFa showed concentration dependent inhibition of forskolin-stimulated cAMP in both hKOR and hMOR-CHO cells; however, the inhibition at 1nM was significantly higher in hKOR cells and comparable to DynA (1-13) than that shown at 20nM in hMOR cells. Chronic treatment of YFa, similar to DynA (1-13), did not show significant change in forskolin-stimulated cAMP level in both hKOR and hMOR cells. However, chronic treatment of morphine and DAMGO showed an increase in forskolin-stimulated cAMP level in hMOR-CHO cells indicating superactivation of adenylyl cyclase. Eu-GTP-γS binding studies of YFa showed a concentration dependent adherent binding with κ- and μ-opioid receptors; however, the latter demonstrated significant binding at higher concentration. Thus the study indicates the chimeric opioid peptide YFa as a potent κ- receptor specific antinociceptive moiety, showing no tolerance and hence may serve as a lead in understanding the mechanism of tolerance development, antinociception and its modulation.
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Affiliation(s)
- Krishan Kumar
- Institute of Genomics and Integrative Biology (CSIR), Mall Road, Delhi, India
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123
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Davis MP. Opioid receptor targeting ligands for pain management: a review and update. Expert Opin Drug Discov 2010; 5:1007-22. [DOI: 10.1517/17460441.2010.511473] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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124
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Banks ML, Rice KC, Negus SS. Antinociceptive interactions between Mu-opioid receptor agonists and the serotonin uptake inhibitor clomipramine in rhesus monkeys: role of Mu agonist efficacy. J Pharmacol Exp Ther 2010; 335:497-505. [PMID: 20675432 DOI: 10.1124/jpet.110.169276] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mu-opioid agonists are effective analgesics but have undesirable effects such as sedation and abuse liability that limit their clinical effectiveness. Serotonergic systems also modulate nociception, and serotonin uptake inhibitors may be useful as adjuncts to enhance analgesic effects and/or attenuate undesirable effects of mu agonists. This study examined the effects of the serotonin uptake inhibitor clomipramine on behavioral effects produced in rhesus monkeys by mu agonists with varying efficacy at mu receptors (nalbuphine < morphine < methadone). Clomipramine and each mu agonist were studied alone and in fixed-proportion mixtures in assays of schedule-controlled responding, thermal nociception, and capsaicin-induced thermal allodynia. In the assay of schedule-controlled responding, all mu agonists dose-dependently decreased response rates. Clomipramine was inactive alone and did not alter the effects of mu agonists. In the assay of thermal nociception, all mu agonists produced dose-dependent antinociception. Clomipramine was inactive alone but produced a proportion-dependent enhancement of the antinociceptive effects of nalbuphine > morphine > methadone. In the assay of capsaicin-induced allodynia, nalbuphine produced dose-dependent antiallodynia. Clomipramine alone was inactive, but as in the assay of thermal nociception, it produced a proportion-dependent enhancement in the effects of nalbuphine. These findings suggest that serotonin uptake inhibitors can selectively enhance the antinociceptive effects of mu agonists in nonhuman primates. These effects of serotonin uptake inhibitors may depend on the proportion of the serotonin uptake inhibitor and the efficacy of the mu agonist. The greatest enhancement was observed with intermediate proportions of clomipramine in combination with the low-efficacy mu agonist nalbuphine.
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Affiliation(s)
- Matthew L Banks
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 North 12th Street, P.O. Box 980613, Richmond, VA 23298, USA
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125
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Analysis of the opioid–opioid combinations according to the nociceptive stimulus in mice. Pharmacol Res 2010; 61:511-8. [DOI: 10.1016/j.phrs.2010.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 02/24/2010] [Accepted: 02/24/2010] [Indexed: 01/10/2023]
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Ansonoff MA, Portoghese PS, Pintar JE. Consequences of opioid receptor mutation on actions of univalent and bivalent kappa and delta ligands. Psychopharmacology (Berl) 2010; 210:161-8. [PMID: 20333506 DOI: 10.1007/s00213-010-1826-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 03/04/2010] [Indexed: 10/19/2022]
Abstract
INTRODUCTION During the past decade, substantial evidence has documented that opioid receptor heterodimers form in cell lines expressing one or more opioid receptors. More recent studies have begun to investigate whether heterodimer formation also occurs in vivo. OBJECTIVES We have used opioid receptor knockout mice to determine whether the in vivo intrathecal (i.t.) pharmacological potency of delta, kappa, and bivalent kappa/delta ligands is altered in the absence of the KOR-1 and/or DOR-1 genes. RESULTS We observe that both NorBNI (a kappa antagonist) and KDN-21 (a kappa/delta bivalent antagonist) specifically inhibit DPDPE but not deltorphin II i.t potency in wild-type mice but that following mutation of KOR-1, the ability of either compound to reduce DPDPE potency is lost. In contrast, knockout of KOR-1 unexpectedly slightly reduces the potency of deltorphin II (delta2) but not DPDPE (delta1). Finally, two compounds with kappa agonist activity, 6'-GNTI (a putative kappa/delta heterodimer selective agonist) and KDAN-18 (kappa agonist/delta antagonist bivalent ligand) show reduced potency in DOR-1 KO mice. CONCLUSIONS These results show, genetically, that bivalent ligands with kappa agonist activity require delta receptors for maximal potency in vivo, which is consistent with the presence of opioid heterodimer/oligomer complexes in vivo, and also highlight the complexity of delta drug action even when complementary pharmacologic and genetic approaches are used.
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Affiliation(s)
- Michael A Ansonoff
- Department of Neuroscience and Cell Biology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA
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Largent-Milnes TM, Vanderah TW. Recently patented and promising ORL-1 ligands: where have we been and where are we going? Expert Opin Ther Pat 2010; 20:291-305. [PMID: 20180617 DOI: 10.1517/13543771003602004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD The interactions of nociceptin/orphanin FQ (N/OFQ) and the opioid receptor-like receptor 1 (nociceptin opioid peptide--NOP) have been implicated in a variety of systems including cardiovascular, respiratory, immune, and the central and peripheral nervous systems. AREAS COVERED IN THIS REVIEW To elucidate the endogenous role of the N/OFQ-NOP system through the use of knockout and knockdown animal preparations, though most advances have been made using a host of synthetic agonists and antagonists. This review gives a brief history of the receptor-ligand discovery, the development of these agonists and antagonists within the last 10 years as published, and the therapeutic indications thereof focusing on pain. WHAT THE READER WILL GAIN The use of NOP ligands in pain has been controversial at best; however, there are indications that both agonists and antagonists have a place in the clinical setting for acute and chronic pain. NOP ligands have potential as novel therapeutics, interestingly, when incorporated into a rationally-designed multi-target agent. TAKE HOME MESSAGE The discovery of N/OFQ and NOP opened a new option for the treatment of pain with the potential for a decreased side effect profile. Numerous compounds have been designed to target this system, the most promising of which have mixed profiles.
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Affiliation(s)
- Tally M Largent-Milnes
- University of Arizona, Department of Pharmacology, 1501 N. Campbell Avenue, Tucson, Arizona 85724-5050, USA
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McDonald J, Leonard AD, Serrano-Gomez A, Young SP, Swanevelder J, Thompson JP, Lambert DG. Assessment of nociceptin/orphanin FQ and micro-opioid receptor mRNA in the human right atrium. Br J Anaesth 2010; 104:698-704. [PMID: 20413378 DOI: 10.1093/bja/aeq089] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The expression of micro (mu: MOP) and nociceptin/orphanin FQ (NOP) receptors in the human myocardium is controversial. In this polymerase chain reaction (PCR)-based study using human right atrial biopsies, we have (i) probed for mRNA encoding NOP receptor and its endogenous peptide precursor, ppN/OFQ, and mRNA encoding MOP and (ii) attempted to correlate expression with cardiac function. METHODS mRNA encoding MOP, NOP, and the precursor for NOP (ppN/OFQ) was assessed by quantitative real-time PCR (Q-PCR) using validated TaqMan primers and compared with a housekeeper (glyceraldehyde-3-phosphate dehydrogenase, GAPDH). Q-PCR data are expressed as the difference in cycle threshold (DeltaC(t)=C(tGene of interest)-C(tGAPDH): high value, low expression) and patients were grouped according to left ventricular ejection fraction (LVEF). RESULTS Forty patients were recruited; NOP, MOP, and ppN/OFQ mRNA were measured in 38, 29, and 10 patients, respectively. DeltaC(t) (median and range) values for NOP and MOP were 10.9 (7.8-13.7) and 16.0 (12.3-18.9), respectively, representing low expression of MOP and approximately 34-fold more NOP. MOP mRNA was not detected in seven samples and with DeltaC(t) values of approximately 20, ppN/OFQ was considered absent. When patients were grouped into normal (>50%) and impaired (<50%) LVEF, there was no difference between the groups for either NOP or MOP. In some patients, intraoperative LVEF was estimated using transoesophageal echocardiography, and there was no correlation with either NOP or MOP. CONCLUSIONS The human right atrium of patients with coronary artery disease and heart failure expresses mRNA encoding NOP and possibly low levels of MOP. This does not correlate with degree of cardiac dysfunction. In addition, the atrium does not express ppN/OFQ mRNA.
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Affiliation(s)
- J McDonald
- Department of Cardiovascular Sciences (Pharmacology and Therapeutics Group), Division of Anaesthesia, Critical Care and Pain Management, University of Leicester, Leicester Royal Infirmary, Leicester, UK
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Balboni G, Salvadori S, Trapella C, Knapp BI, Bidlack JM, Lazarus LH, Peng X, Neumeyer JL. Evolution of the Bifunctional Lead μ Agonist / δ Antagonist Containing the Dmt-Tic Opioid Pharmacophore. ACS Chem Neurosci 2010; 1:155-164. [PMID: 20352071 DOI: 10.1021/cn900025j] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Based on a renewed importance recently attributed to bi- or multifunctional opioids, we report the synthesis and pharmacological evaluation of some analogues derived from our lead μ agonist / δ antagonist, H-Dmt-Tic-Gly-NH-Bzl. Our previous studies focused on the importance of the C-teminal benzyl function in the induction of such bifunctional activity. The introduction of some substituents in the para position of the phenyl ring (-Cl, -CH(3), partially -NO(2), inactive -NH(2)) was found to give a more potent μ agonist / antagonist effect associated with a relatively unmodified δ antagonist activity (pA(2) = 8.28-9.02). Increasing the steric hindrance of the benzyl group (using diphenylmethyl and tetrahydroisoquinoline functionalities) substantially maintained the μ agonist and δ antagonist activities of the lead compound. Finally and quite unexpectedly D-Tic2, considered as a wrong opioid message now; inserted into the reference compound in lieu of L-Tic, provided a μ agonist / δ agonist better than our reference ligand (H-Dmt-Tic-Gly-NH-Ph) and was endowed with the same pharmacological profile.
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Affiliation(s)
- Gianfranco Balboni
- Department of Toxicology, University of Cagliari, I-09124, Cagliari, Italy
| | - Severo Salvadori
- Department of Pharmaceutical Sciences and Biotechnology Center, University of Ferrara, I-44100 Ferrara, Italy
| | - Claudio Trapella
- Department of Pharmaceutical Sciences and Biotechnology Center, University of Ferrara, I-44100 Ferrara, Italy
| | - Brian I. Knapp
- Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642
| | - Jean M. Bidlack
- Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642
| | - Lawrence H. Lazarus
- Medicinal Chemistry Group, Laboratory of Pharmacology, National Institute of Environmental Health Sciences, Research Triangle Park, North 6 Carolina 27709
| | - Xuemei Peng
- Alcohol and Drug Abuse Research Center, McLean Hospital, Harvard Medical School, 115 Mill Street, Belmont, Massachusetts 02478
| | - John L. Neumeyer
- Alcohol and Drug Abuse Research Center, McLean Hospital, Harvard Medical School, 115 Mill Street, Belmont, Massachusetts 02478
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Colvin L, Fallon M. Opioid-induced hyperalgesia: a clinical challenge. Br J Anaesth 2010; 104:125-7. [DOI: 10.1093/bja/aep392] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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Current awareness: Pharmacoepidemiology and drug safety. Pharmacoepidemiol Drug Saf 2009. [DOI: 10.1002/pds.1846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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