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Galal KA, Obeng S, Pallares VLC, Senetra A, Seabra MABL, Awad A, McCurdy CR. Guanidine-to-piperidine switch affords high affinity small molecule NPFF ligands with preference for NPFF1-R and NPFF2-R subtypes. Eur J Med Chem 2024; 269:116330. [PMID: 38522114 DOI: 10.1016/j.ejmech.2024.116330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 03/03/2024] [Accepted: 03/11/2024] [Indexed: 03/26/2024]
Abstract
The Neuropeptide FF (NPFF) receptor system is known to modulate opioid actions and has been shown to mediate opioid-induced hyperalgesia and tolerance. The lack of subtype selective small molecule compounds has hampered further exploration of the pharmacology of this receptor system. The vast majority of available NPFF ligands possess a highly basic guanidine group, including our lead small molecule, MES304. Despite providing strong receptor binding, the guanidine group presents a potential pharmacokinetic liability for in vivo pharmacological tool development. Through structure-activity relationship exploration, we were able to modify our lead molecule MES304 to arrive at guanidine-free NPFF ligands. The novel piperidine analogues 8b and 16a are among the few non-guanidine based NPFF ligands known in literature. Both compounds displayed nanomolar NPFF-R binding affinity approaching that of the parent molecule. Moreover, while MES304 was non-subtype selective, these two analogues presented new starting points for subtype selective scaffolds, whereby 8b displayed a 15-fold preference for NPFF1-R, and 16a demonstrated an 8-fold preference for NPFF2-R. Both analogues showed no agonist activity on either receptor subtype in the in vitro functional activity assay, while 8b displayed antagonistic properties at NPFF1-R. The calculated physicochemical properties of 8b and 16a were also shown to be more favorable for in vivo tool design. These results indicate the possibility of developing potent, subtype selective NPFF ligands devoid of a guanidine functionality.
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Affiliation(s)
- Kareem A Galal
- Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA.
| | - Samuel Obeng
- Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA; Department of Pharmaceutical Sciences, Jerry H. Hodge School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106, USA
| | - Victoria L C Pallares
- Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA
| | - Alexandria Senetra
- Department of Pharmaceutics, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA
| | - Maria A B L Seabra
- Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA
| | - Ahmed Awad
- Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA
| | - Christopher R McCurdy
- Department of Medicinal Chemistry, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA; Department of Pharmaceutics, College of Pharmacy, The University of Florida, Gainesville, FL, 32610, USA; UF Translational Drug Development Core, The University of Florida, Gainesville, FL, 32610, USA
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2
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Angeli A, Micheli L, Turnaturi R, Pasquinucci L, Parenti C, Alterio V, Di Fiore A, De Simone G, Monti SM, Carta F, Di Cesare Mannelli L, Ghelardini C, Supuran CT. Discovery of a novel series of potent carbonic anhydrase inhibitors with selective affinity for μ Opioid receptor for Safer and long-lasting analgesia. Eur J Med Chem 2023; 260:115783. [PMID: 37678143 DOI: 10.1016/j.ejmech.2023.115783] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/09/2023]
Abstract
In this study, we investigated the development of dual-targeted ligands that bind to both μ-opioid receptor (MOR) and carbonic anhydrase (CA) enzymes, using fentanyl structure as a template. We synthesized and evaluated 21 novel compounds with dual-targeted affinity identifying the lead candidate compound 8, showing selective affinity for MOR and potent inhibition of several cytosolic CA isoforms. By means of repeated treatment of 3 daily administrations for 17 days, fentanyl (0.1 mg/kg, subcutaneously) led to tolerance development, pain threshold alterations and withdrawal symptoms in CD-1 mice, as well as astrocyte and microglia activation in the dorsal horn of the lumbar spinal cord. In contrast, compound 8 (0.32 mg/kg s.c.) maintained stable during days its analgesic effect at the higher dose tested with fewer withdrawal symptoms, allodynia development and glial cells activation. Our results suggest that targeting both MOR and CA enzymes can lead to the development of new class of potent analgesic agents with fewer side effects and reduced tolerance development. Further studies are needed to explore the potential mechanisms underlying these effects and to further optimize the therapeutic potential of these compounds.
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Affiliation(s)
- Andrea Angeli
- NEUROFARBA Department, Sezione di Scienze Farmaceutiche, University of Florence, Via Ugo Schiff 6, 50019, Sesto Fiorentino, Florence, Italy.
| | - Laura Micheli
- Pharmacology and Toxicology Section, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale G. Pieraccini, 50139, Florence, Italy
| | - Rita Turnaturi
- Department of Drug Sciences and Health, Medicinal Chemistry Section, Università degli Studi di Catania, Viale A. Doria, 6, 95125, Catania, Italy
| | - Lorella Pasquinucci
- Department of Drug Sciences and Health, Medicinal Chemistry Section, Università degli Studi di Catania, Viale A. Doria, 6, 95125, Catania, Italy
| | - Carmela Parenti
- Department of Drug Sciences and Health, Pharmacology and Toxicology Section, Università degli Studi di Catania, Viale A. Doria, 6, 95125, Catania, Italy
| | - Vincenzo Alterio
- Istituto di Biostrutture e Bioimmagini-CNR, via Pietro Castellino, 111, 80131, Naples, Italy
| | - Anna Di Fiore
- Istituto di Biostrutture e Bioimmagini-CNR, via Pietro Castellino, 111, 80131, Naples, Italy
| | - Giuseppina De Simone
- Istituto di Biostrutture e Bioimmagini-CNR, via Pietro Castellino, 111, 80131, Naples, Italy
| | - Simona Maria Monti
- Istituto di Biostrutture e Bioimmagini-CNR, via Pietro Castellino, 111, 80131, Naples, Italy
| | - Fabrizio Carta
- NEUROFARBA Department, Sezione di Scienze Farmaceutiche, University of Florence, Via Ugo Schiff 6, 50019, Sesto Fiorentino, Florence, Italy
| | - Lorenzo Di Cesare Mannelli
- Pharmacology and Toxicology Section, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale G. Pieraccini, 50139, Florence, Italy
| | - Carla Ghelardini
- Pharmacology and Toxicology Section, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale G. Pieraccini, 50139, Florence, Italy
| | - Claudiu T Supuran
- NEUROFARBA Department, Sezione di Scienze Farmaceutiche, University of Florence, Via Ugo Schiff 6, 50019, Sesto Fiorentino, Florence, Italy
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3
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Li Y, Eans SO, Ganno-Sherwood M, Eliasof A, Houghten RA, McLaughlin JP. Identification and Pharmacological Characterization of a Low-Liability Antinociceptive Bifunctional MOR/DOR Cyclic Peptide. Molecules 2023; 28:7548. [PMID: 38005269 PMCID: PMC10674865 DOI: 10.3390/molecules28227548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/04/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
Peptide-based opioid ligands are important candidates for the development of novel, safer, and more effective analgesics to treat pain. To develop peptide-based safer analgesics, we synthesized a mixture-based cyclic pentapeptide library containing a total of 24,624 pentapeptides and screened the mixture-based library samples using a 55 °C warm water tail-withdrawal assay. Using this phenotypic screening approach, we deconvoluted the mixture-based samples to identify a novel cyclic peptide Tyr-[D-Lys-Dap(Ant)-Thr-Gly] (CycloAnt), which produced dose- and time-dependent antinociception with an ED50 (and 95% confidence interval) of 0.70 (0.52-0.97) mg/kg i.p. mediated by the mu-opioid receptor (MOR). Additionally, higher doses (≥3 mg/kg, i.p.) of CycloAnt antagonized delta-opioid receptors (DOR) for at least 3 h. Pharmacological characterization of CycloAnt showed the cyclic peptide did not reduce breathing rate in mice at doses up to 15 times the analgesic ED50 value, and produced dramatically less hyperlocomotion than the MOR agonist, morphine. While chronic administration of CycloAnt resulted in antinociceptive tolerance, it was without opioid-induced hyperalgesia and with significantly reduced signs of naloxone-precipitated withdrawal, which suggested reduced physical dependence compared to morphine. Collectively, the results suggest this dual MOR/DOR multifunctional ligand is an excellent lead for the development of peptide-based safer analgesics.
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Affiliation(s)
- Yangmei Li
- College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA;
| | - Shainnel O. Eans
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA;
| | - Michelle Ganno-Sherwood
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL 34987, USA; (M.G.-S.); (R.A.H.)
| | - Abbe Eliasof
- College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA;
| | - Richard A. Houghten
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL 34987, USA; (M.G.-S.); (R.A.H.)
| | - Jay P. McLaughlin
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA;
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4
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Expression of Human Immunodeficiency Virus Transactivator of Transcription (HIV-Tat 1-86) Protein Alters Nociceptive Processing that is Sensitive to Anti-Oxidant and Anti-Inflammatory Interventions. J Neuroimmune Pharmacol 2022; 17:152-164. [PMID: 33619645 PMCID: PMC8380260 DOI: 10.1007/s11481-021-09985-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 01/24/2021] [Indexed: 12/29/2022]
Abstract
Despite the success of combined antiretroviral therapy (cART) in reducing viral load, a substantial portion of Human Immunodeficiency Virus (HIV)+ patients report chronic pain. The exact mechanism underlying this co-morbidity even with undetectable viral load remains unknown, but the transactivator of transcription (HIV-Tat) protein is of particular interest. Functional HIV-Tat protein is observed even in cerebrospinal fluid of patients who have an undetectable viral load. It is hypothesized that Tat protein exposure is sufficient to induce neuropathic pain-like manifestations via both activation of microglia and generation of oxidative stress. iTat mice conditionally expressed Tat(1-86) protein in the central nervous system upon daily administration of doxycycline (100 mg/kg/d, i.p., up to 14 days). The effect of HIV-Tat protein exposure on the well-being of the animal was assessed using sucrose-evoked grooming and acute nesting behavior for pain-depressed behaviors, and the development of hyperalgesia assessed with warm-water tail-withdrawal and von Frey assays for thermal hyperalgesia and mechanical allodynia, respectively. Tissue harvested at select time points was used to assess ex vivo alterations in oxidative stress, astrocytosis and microgliosis, and blood-brain barrier integrity with assays utilizing fluorescence-based indicators. Tat protein induced mild thermal hyperalgesia but robust mechanical allodynia starting after 4 days of exposure, reaching a nadir after 7 days. Changes in nociceptive processing were associated with reduced sucrose-evoked grooming behavior without altering acute nesting behavior, and in spinal cord dysregulated free radical generation as measured by DCF fluorescence intensity, altered immunohistochemical expression of the gliotic markers, Iba-1 and GFAP, and increased permeability of the blood-brain barrier to the small molecule fluorescent tracer, sodium fluorescein, in a time-dependent manner. Pretreatment with the anti-inflammatory, indomethacin (1 mg/kg/d, i.p.), the antioxidant, methylsulfonylmethane (100 mg/kg/d i.p.), or the immunomodulatory agent, dimethylfumarate (100 mg/kg/d p.o.) thirty minutes prior to daily injections of doxycycline (100 mg/kg/d i.p.) over 7 days significantly attenuated the development of Tat-induced mechanical allodynia. Collectively, the data suggests that even acute exposure to HIV-1 Tat protein at pathologically relevant levels is sufficient to produce select neurophysiological and behavioral manifestations of chronic pain consistent with that reported by HIV-positive patients.
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5
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Wilson LL, Chakraborty S, Eans SO, Cirino TJ, Stacy HM, Simons CA, Uprety R, Majumdar S, McLaughlin JP. Kratom Alkaloids, Natural and Semi-Synthetic, Show Less Physical Dependence and Ameliorate Opioid Withdrawal. Cell Mol Neurobiol 2021; 41:1131-1143. [PMID: 33433723 PMCID: PMC8164968 DOI: 10.1007/s10571-020-01034-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 12/21/2020] [Indexed: 01/13/2023]
Abstract
Chronic administration of opioids produces physical dependence and opioid-induced hyperalgesia. Users claim the Thai traditional tea "kratom" and component alkaloid mitragynine ameliorate opioid withdrawal without increased sensitivity to pain. Testing these claims, we assessed the combined kratom alkaloid extract (KAE) and two individual alkaloids, mitragynine (MG) and the analog mitragynine pseudoindoxyl (MP), evaluating their ability to produce physical dependence and induce hyperalgesia after chronic administration, and as treatments for withdrawal in morphine-dependent subjects. C57BL/6J mice (n = 10/drug) were administered repeated saline, or graded, escalating doses of morphine (intraperitoneal; i.p.), kratom alkaloid extract (orally, p.o.), mitragynine (p.o.), or MP (subcutaneously, s.c.) for 5 days. Mice treated chronically with morphine, KAE, or mitragynine demonstrated significant drug-induced hyperalgesia by day 5 in a 48 °C warm-water tail-withdrawal test. Mice were then administered naloxone (10 mg/kg, s.c.) and tested for opioid withdrawal signs. Kratom alkaloid extract and the two individual alkaloids demonstrated significantly fewer naloxone-precipitated withdrawal signs than morphine-treated mice. Additional C57BL/6J mice made physically dependent on morphine were then used to test the therapeutic potential of combined KAE, mitragynine, or MP given twice daily over the next 3 days at either a fixed dose or in graded, tapering descending doses. When administered naloxone, mice treated with KAE, mitragynine, or MP under either regimen demonstrated significantly fewer signs of precipitated withdrawal than control mice that continued to receive morphine. In conclusion, while retaining some liabilities, kratom, mitragynine, and mitragynine pseudoindoxyl produced significantly less physical dependence and ameliorated precipitated withdrawal in morphine-dependent animals, suggesting some clinical value.
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MESH Headings
- Analgesics, Opioid/administration & dosage
- Analgesics, Opioid/adverse effects
- Animals
- Male
- Mice
- Mice, Inbred C57BL
- Mitragyna
- Morphine Dependence/metabolism
- Morphine Dependence/prevention & control
- Morphine Dependence/psychology
- Pain Measurement/drug effects
- Pain Measurement/methods
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/metabolism
- Secologanin Tryptamine Alkaloids/administration & dosage
- Secologanin Tryptamine Alkaloids/adverse effects
- Secologanin Tryptamine Alkaloids/chemical synthesis
- Secologanin Tryptamine Alkaloids/isolation & purification
- Substance Withdrawal Syndrome/metabolism
- Substance Withdrawal Syndrome/prevention & control
- Substance Withdrawal Syndrome/psychology
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Affiliation(s)
- Lisa L Wilson
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Soumen Chakraborty
- Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Shainnel O Eans
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Thomas J Cirino
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Heather M Stacy
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Chloe A Simons
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Rajendra Uprety
- Molecular Pharmacology and Chemistry Program and Department of Neurology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Susruta Majumdar
- Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Jay P McLaughlin
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA.
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Wojciechowski P, Andrzejewski K, Kaczyńska K. Intracerebroventricular Neuropeptide FF Diminishes the Number of Apneas and Cardiovascular Effects Produced by Opioid Receptors' Activation. Int J Mol Sci 2020; 21:ijms21238931. [PMID: 33255594 PMCID: PMC7728097 DOI: 10.3390/ijms21238931] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 01/23/2023] Open
Abstract
The opioid-induced analgesia is associated with a number of side effects such as addiction, tolerance and respiratory depression. The involvement of neuropeptide FF (NPFF) in modulation of pain perception, opioid-induced tolerance and dependence was well documented in contrast to respiratory depression. Therefore, the aim of the present study was to examine the potency of NPFF to block post-opioid respiratory depression, one of the main adverse effects of opioid therapy. Urethane-chloralose anaesthetized Wistar rats were injected either intravenously (iv) or intracerebroventricularly (icv) with various doses of NPFF prior to iv endomorphin-1 (EM-1) administration. Iv NPFF diminished the number of EM-1-induced apneas without affecting their length and without influence on the EM-1 induced blood pressure decline. Icv pretreatment with NPFF abolished the occurrence of post-EM-1 apneas and reduced also the maximal drop in blood pressure and heart rate. These effects were completely blocked by the NPFF receptor antagonist RF9, which was given as a mixture with NPFF before systemic EM-1 administration. In conclusion, our results showed that centrally administered neuropeptide FF is effective in preventing apnea evoked by stimulation of μ-opioid receptors and the effect was due to activation of central NPFF receptors. Our finding indicates a potential target for reversal of opioid-induced respiratory depression.
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7
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Nguyen T, Marusich J, Li JX, Zhang Y. Neuropeptide FF and Its Receptors: Therapeutic Applications and Ligand Development. J Med Chem 2020; 63:12387-12402. [PMID: 32673481 DOI: 10.1021/acs.jmedchem.0c00643] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The endogenous neuropeptide FF (NPFF) and its two cognate G protein-coupled receptors, Neuropeptide FF Receptors 1 and 2 (NPFFR1 and NPFFR2), represent a relatively new target system for many therapeutic applications including pain regulation, modulation of opioid side effects, drug reward, anxiety, cardiovascular conditions, and other peripheral effects. Since the cloning of NPFFR1 and NPFFR2 in 2000, significant progress has been made to understand their pharmacological roles and interactions with other receptor systems, notably the opioid receptors. A variety of NPFFR ligands with different mechanisms of action (agonists or antagonists) have been discovered although with limited subtype selectivities. Differential pharmacological effects have been observed for many of these NPFFR ligands, depending on assays/models employed and routes of administration. In this Perspective, we highlight the therapeutic potentials, current knowledge gaps, and latest updates of the development of peptidic and small molecule NPFFR ligands as tool compounds and therapeutic candidates.
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Affiliation(s)
- Thuy Nguyen
- Center for Drug Discovery, Research Triangle Institute, 3040 East Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
| | - Julie Marusich
- Center for Drug Discovery, Research Triangle Institute, 3040 East Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
| | - Jun-Xu Li
- Department of Pharmacology and Toxicology, University at Buffalo, the State University of New York, Buffalo, New York 14203, United States
| | - Yanan Zhang
- Center for Drug Discovery, Research Triangle Institute, 3040 East Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
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8
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King TI, Roewekamp AC, Sharma A, Harrison S, Mesangeau C, Mottinelli M, Kamble SH, McCurdy CR, Avery BA. Bioanalytical method development and validation of MES207, a neuropeptide FF receptor antagonist, and its application in preclinical pharmacokinetics. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1134-1135:121875. [DOI: 10.1016/j.jchromb.2019.121875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/23/2019] [Accepted: 11/01/2019] [Indexed: 11/28/2022]
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9
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Gao YH, Lovreković V, Kussayeva A, Chen DY, Margetić D, Chen ZL. The photodynamic activities of dimethyl 13 1-[2-(guanidinyl)ethylamino] chlorin e 6 photosensitizers in A549 tumor. Eur J Med Chem 2019; 177:144-152. [PMID: 31132530 DOI: 10.1016/j.ejmech.2019.05.050] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/03/2019] [Accepted: 05/17/2019] [Indexed: 12/22/2022]
Abstract
Effective photosensitizers are particularly important factor in clinical photodynamic therapy (PDT). However, there is a scarcity of photosensitizers for simultaneous cancer photo-diagnosis and targeted PDT. Herein, two novel dimethyl 2-(guanidinyl)ethylamino chlorin e6 photosensitizers were synthesized and their efficacy in PDT in A549 tumor was investigated. It was shown that compounds 3 and 4 have a long absorption wavelength in the near infrared region and strong fluorescence emission with slow photo-bleaching rate and markedly strong ability of 1O2 generation. They exhibited lower cytotoxicity and higher photo-cytotoxicity in vitro compared to the known anticancer drug m-THPC in MTT assay in A549 lung cancer cell lines. Compound 4 exhibit better inhibition effect than compound 3 and the IC50 value of compound 4 was 0.197 μM/L under 2 J/cm2 laser irradiation, while compound 3 showed better anti-tumor effects compared to compound 4 in vivo. Intracellular ROS generation was found to be responsible for apoptotic cell death in DCFDA assay. Subcellular localization confirmed the damage site of compounds 3 and 4 in PDT. These findings suggest that the two novel photosensitizers might serve as potential photosensitizers for improved therapeutic efficiency of PDT.
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Affiliation(s)
- Ying-Hua Gao
- Department of Pharmaceutical Science & Technology, College of Chemistry and Biology, Donghua University, Shanghai, 201620, China
| | - Vanda Lovreković
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička c. 54, 10000, Croatia
| | - Akmaral Kussayeva
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička c. 54, 10000, Croatia
| | - Dan-Ye Chen
- Department of Pharmaceutical Science & Technology, College of Chemistry and Biology, Donghua University, Shanghai, 201620, China
| | - Davor Margetić
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička c. 54, 10000, Croatia.
| | - Zhi-Long Chen
- Department of Pharmaceutical Science & Technology, College of Chemistry and Biology, Donghua University, Shanghai, 201620, China.
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10
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A bifunctional-biased mu-opioid agonist-neuropeptide FF receptor antagonist as analgesic with improved acute and chronic side effects. Pain 2019; 159:1705-1718. [PMID: 29708942 DOI: 10.1097/j.pain.0000000000001262] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Opioid analgesics, such as morphine, oxycodone, and fentanyl, are the cornerstones for treating moderate to severe pain. However, on chronic administration, their efficiency is limited by prominent side effects such as analgesic tolerance and dependence liability. Neuropeptide FF (NPFF) and its receptors (NPFF1R and NPFF2R) are recognized as an important pronociceptive system involved in opioid-induced hyperalgesia and analgesic tolerance. In this article, we report the design of multitarget peptidomimetic compounds that show high-affinity binding to the mu-opioid receptor (MOPr) and NPFFRs. In vitro characterization of these compounds led to identification of KGFF03 and KGFF09 as G-protein-biased MOPr agonists with full agonist or antagonist activity at NPFFRs, respectively. In agreement with their biased MOPr agonism, KGFF03/09 showed reduced respiratory depression in mice, as compared to the unbiased parent opioid agonist KGOP01. Chronic subcutaneous administration of KGOP01 and KGFF03 in mice rapidly induced hyperalgesia and analgesic tolerance, effects that were not observed on chronic treatment with KGFF09. This favorable profile was further confirmed in a model of persistent inflammatory pain. In addition, we showed that KGFF09 induced less physical dependence compared with KGOP01 and KGFF03. Altogether, our data establish that combining, within a single molecule, the G-protein-biased MOPr agonism and NPFFR antagonism have beneficial effects on both acute and chronic side effects of conventional opioid analgesics. This strategy can lead to the development of novel and potent antinociceptive drugs with limited side effects on acute and chronic administration.
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11
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Hammoud H, Elhabazi K, Quillet R, Bertin I, Utard V, Laboureyras E, Bourguignon JJ, Bihel F, Simonnet G, Simonin F, Schmitt M. Aminoguanidine Hydrazone Derivatives as Nonpeptide NPFF1 Receptor Antagonists Reverse Opioid Induced Hyperalgesia. ACS Chem Neurosci 2018; 9:2599-2609. [PMID: 29727163 DOI: 10.1021/acschemneuro.8b00099] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Neuropeptide FF receptors (NPFF1R and NPFF2R) and their endogenous ligand neuropeptide FF have been shown previously to display antiopioid properties and to play a critical role in the adverse effects associated with chronic administrations of opiates including the development of opioid-induced hyperalgesia and analgesic tolerance. In this work, we sought to identify novel NPFF receptors ligands by focusing our interest in a series of heterocycles as rigidified nonpeptide NPFF receptor ligands, starting from already described aminoguanidine hydrazones (AGHs). Binding experiments and functional assays highlighted AGH 1n and its rigidified analogue 2-amino-dihydropyrimidine 22e for in vivo experiments. As shown earlier with the prototypical dipeptide antagonist RF9, both 1n and 22e reduced significantly the long lasting fentanyl-induced hyperalgesia in rodents. Altogether these data indicate that AGH rigidification maintains nanomolar affinities for both NPFF receptors, while improving antagonist character toward NPFF1R.
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Affiliation(s)
- Hassan Hammoud
- University of Strasbourg, CNRS,
UMR7200, Faculty of Pharmacy, F-67401 Illkirch Graffenstaden, France
| | - Khadija Elhabazi
- Université
de Strasbourg, CNRS, Biotechnologie et Signalisation Cellulaire, UMR
7242, F-67401 Illkirch Graffenstaden, France
| | - Raphäelle Quillet
- Université
de Strasbourg, CNRS, Biotechnologie et Signalisation Cellulaire, UMR
7242, F-67401 Illkirch Graffenstaden, France
| | - Isabelle Bertin
- Université
de Strasbourg, CNRS, Biotechnologie et Signalisation Cellulaire, UMR
7242, F-67401 Illkirch Graffenstaden, France
| | - Valérie Utard
- Université
de Strasbourg, CNRS, Biotechnologie et Signalisation Cellulaire, UMR
7242, F-67401 Illkirch Graffenstaden, France
| | - Emilie Laboureyras
- Homéostasie-Allostasie-Pathologie-Réhabilitation,
UMR 5287 CNRS, Université de Bordeaux, 33076 Bordeaux, France
| | - Jean-Jacques Bourguignon
- University of Strasbourg, CNRS,
UMR7200, Faculty of Pharmacy, F-67401 Illkirch Graffenstaden, France
| | - Frédéric Bihel
- University of Strasbourg, CNRS,
UMR7200, Faculty of Pharmacy, F-67401 Illkirch Graffenstaden, France
| | - Guy Simonnet
- Homéostasie-Allostasie-Pathologie-Réhabilitation,
UMR 5287 CNRS, Université de Bordeaux, 33076 Bordeaux, France
| | - Frédéric Simonin
- Université
de Strasbourg, CNRS, Biotechnologie et Signalisation Cellulaire, UMR
7242, F-67401 Illkirch Graffenstaden, France
| | - Martine Schmitt
- University of Strasbourg, CNRS,
UMR7200, Faculty of Pharmacy, F-67401 Illkirch Graffenstaden, France
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12
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Nguyen T, Decker AM, Langston TL, Mathews KM, Siemian JN, Li JX, Harris DL, Runyon SP, Zhang Y. Discovery of Novel Proline-Based Neuropeptide FF Receptor Antagonists. ACS Chem Neurosci 2017; 8:2290-2308. [PMID: 28737888 DOI: 10.1021/acschemneuro.7b00219] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The neuropeptide FF (NPFF) system has been implicated in a number of physiological processes including modulating the pharmacological activity of opioid analgesics and several other classes of drugs of abuse. In this study, we report the discovery of a novel proline scaffold with antagonistic activity at the NPFF receptors through a high throughput screening campaign using a functional calcium mobilization assay. Focused structure-activity relationship studies on the initial hit 1 have resulted in several analogs with calcium mobilization potencies in the submicromolar range and modest selectivity for the NPFF1 receptor. Affinities and potencies of these compounds were confirmed in radioligand binding and functional cAMP assays. Two compounds, 16 and 33, had good solubility and blood-brain barrier permeability that fall within the range of CNS permeant candidates without the liability of being a P-glycoprotein substrate. Finally, both compounds reversed fentanyl-induced hyperalgesia in rats when administered intraperitoneally. Together, these results point to the potential of these proline analogs as promising NPFF receptor antagonists.
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Affiliation(s)
- Thuy Nguyen
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
| | - Ann M. Decker
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
| | - Tiffany L. Langston
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
| | - Kelly M. Mathews
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
| | - Justin N. Siemian
- Department of Pharmacology and Toxicology, University at Buffalo, the State University of New York, Buffalo, New York 14214, United States
| | - Jun-Xu Li
- Department of Pharmacology and Toxicology, University at Buffalo, the State University of New York, Buffalo, New York 14214, United States
| | - Danni L. Harris
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
| | - Scott P. Runyon
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
| | - Yanan Zhang
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, United States
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13
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Journigan VB, Polgar WE, Tuan EW, Lu J, Daga PR, Zaveri NT. Probing ligand recognition of the opioid pan antagonist AT-076 at nociceptin, kappa, mu, and delta opioid receptors through structure-activity relationships. Sci Rep 2017; 7:13255. [PMID: 29038479 PMCID: PMC5643385 DOI: 10.1038/s41598-017-13129-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/18/2017] [Indexed: 11/15/2022] Open
Abstract
Few opioid ligands binding to the three classic opioid receptor subtypes, mu, kappa and delta, have high affinity at the fourth opioid receptor, the nociceptin/orphanin FQ receptor (NOP). We recently reported the discovery of AT-076 (1), (R)-7-hydroxy-N-((S)-1-(4-(3-hydroxyphenyl)piperidin-1-yl)-3-methylbutan-2-yl)-1,2,3,4-tetrahydroisoquinoline-3-carboxamide, a pan antagonist with nanomolar affinity for all four subtypes. Since AT-076 binds with high affinity at all four subtypes, we conducted a structure-activity relationship (SAR) study to probe ligand recognition features important for pan opioid receptor activity, using chemical modifications of key pharmacophoric groups. SAR analysis of the resulting analogs suggests that for the NOP receptor, the entire AT-076 scaffold is crucial for high binding affinity, but the binding mode is likely different from that of NOP antagonists C-24 and SB-612111 bound in the NOP crystal structure. On the other hand, modifications of the 3-hydroxyphenyl pharmacophore, but not the 7-hydroxy Tic pharmacophore, are better tolerated at kappa and mu receptors and yield very high affinity multifunctional (e.g. 12) or highly selective (e.g. 16) kappa ligands. With the availability of the opioid receptor crystal structures, our SAR analysis of the common chemotype of AT-076 suggests rational approaches to modulate binding selectivity, enabling the design of multifunctional or selective opioid ligands from such scaffolds.
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MESH Headings
- Humans
- Narcotic Antagonists/chemistry
- Narcotic Antagonists/pharmacology
- Opioid Peptides/chemistry
- Receptors, Opioid/chemistry
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/chemistry
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/chemistry
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/chemistry
- Structure-Activity Relationship
- Nociceptin
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Affiliation(s)
- V Blair Journigan
- Astraea Therapeutics, 320 Logue Avenue, Suite 142, Mountain View, CA, 94043, USA
- Marshall University School of Pharmacy, Department of Pharmaceutical Sciences, One John Marshall Drive, Huntington, WV 25755, USA
| | - Willma E Polgar
- Astraea Therapeutics, 320 Logue Avenue, Suite 142, Mountain View, CA, 94043, USA
| | - Edward W Tuan
- Astraea Therapeutics, 320 Logue Avenue, Suite 142, Mountain View, CA, 94043, USA
| | - James Lu
- Astraea Therapeutics, 320 Logue Avenue, Suite 142, Mountain View, CA, 94043, USA
| | - Pankaj R Daga
- Astraea Therapeutics, 320 Logue Avenue, Suite 142, Mountain View, CA, 94043, USA
| | - Nurulain T Zaveri
- Astraea Therapeutics, 320 Logue Avenue, Suite 142, Mountain View, CA, 94043, USA.
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14
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Elhabazi K, Humbert JP, Bertin I, Quillet R, Utard V, Schneider S, Schmitt M, Bourguignon JJ, Laboureyras E, Ben Boujema M, Simonnet G, Ancel C, Simonneaux V, Beltramo M, Bucher B, Sorg T, Meziane H, Schneider E, Petit-Demoulière B, Ilien B, Bihel F, Simonin F. RF313, an orally bioavailable neuropeptide FF receptor antagonist, opposes effects of RF-amide-related peptide-3 and opioid-induced hyperalgesia in rodents. Neuropharmacology 2017; 118:188-198. [DOI: 10.1016/j.neuropharm.2017.03.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 02/27/2017] [Accepted: 03/06/2017] [Indexed: 02/08/2023]
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15
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Chronic activation of NPFFR2 stimulates the stress-related depressive behaviors through HPA axis modulation. Psychoneuroendocrinology 2016; 71:73-85. [PMID: 27243477 DOI: 10.1016/j.psyneuen.2016.05.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 05/11/2016] [Accepted: 05/13/2016] [Indexed: 01/16/2023]
Abstract
Neuropeptide FF (NPFF) is a morphine-modulating peptide that regulates the analgesic effect of opioids, and also controls food consumption and cardiovascular function through its interaction with two cognate receptors, NPFFR1 and NPFFR2. In the present study, we explore a novel modulatory role for NPFF-NPFFR2 in stress-related depressive behaviors. In a mouse model of chronic mild stress (CMS)-induced depression, the expression of NPFF significantly increased in the hypothalamus, hippocampus, medial prefrontal cortex (mPFC) and amygdala. In addition, transgenic (Tg) mice over-expressing NPFFR2 displayed clear depression and anxiety-like behaviors with hyperactivity in the hypothalamic-pituitary-adrenal (HPA) axis, reduced expression of glucocorticoid receptor (GR) and neurogenesis in the hippocampus. Furthermore, acute treatment of NPFFR2 agonists in wild-type (WT) mice enhanced the activity of the HPA axis, and chronic administration resulted in depressive and anxiety-like behaviors. Chronic stimulation of NPFFR2 also decreased the expression of hippocampal GR and led to persistent activation of the HPA axis. Strikingly, bilateral intra-paraventricular nucleus (PVN) injection of NPFFR2 shRNA predominately inhibits the depressive-like behavior in CMS-exposed mice. Antidepressants, fluoxetine and ketamine, effectively relieved the depressive behaviors of NPFFR2-Tg mice. We speculate that persistent NPFFR2 activation, in particular in the hypothalamus, up-regulates the HPA axis and results in long-lasting increases in circulating corticosterone (CORT), consequently damaging hippocampal function. This novel role of NPFFR2 in regulating the HPA axis and hippocampal function provides a new avenue for combating depression and anxiety-like disorder.
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16
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Abstract
Opioid analgesics continue to be the mainstay of pharmacologic treatment of moderate to severe pain. Many patients, particularly those suffering from chronic pain, require chronic high-dose analgesic therapy. Achieving clinical efficacy and tolerability of such treatment regimens is hampered by the appearance of opioid-induced side effects such as tolerance, hyperalgesia and withdrawal syndrome. Among the therapeutic options to improve the opioid effectiveness, this current review focuses on strategies combining opioids to other drugs that can modulate opioid-mediated effects. We will discuss about experimental evidences reported for several potential opioid adjuvants, including N-methyl-d-aspartate receptor antagonists, 5-HT7 agonists, sigma-1 antagonists, I2-R ligands, cholecystokinin antagonists, neuropeptide FF-R antagonists and toll-like receptor 4 antagonists.
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17
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Quillet R, Ayachi S, Bihel F, Elhabazi K, Ilien B, Simonin F. RF-amide neuropeptides and their receptors in Mammals: Pharmacological properties, drug development and main physiological functions. Pharmacol Ther 2016; 160:84-132. [PMID: 26896564 DOI: 10.1016/j.pharmthera.2016.02.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RF-amide neuropeptides, with their typical Arg-Phe-NH2 signature at their carboxyl C-termini, belong to a lineage of peptides that spans almost the entire life tree. Throughout evolution, RF-amide peptides and their receptors preserved fundamental roles in reproduction and feeding, both in Vertebrates and Invertebrates. The scope of this review is to summarize the current knowledge on the RF-amide systems in Mammals from historical aspects to therapeutic opportunities. Taking advantage of the most recent findings in the field, special focus will be given on molecular and pharmacological properties of RF-amide peptides and their receptors as well as on their implication in the control of different physiological functions including feeding, reproduction and pain. Recent progress on the development of drugs that target RF-amide receptors will also be addressed.
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Affiliation(s)
- Raphaëlle Quillet
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Safia Ayachi
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Frédéric Bihel
- Laboratoire Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, Illkirch, France
| | - Khadija Elhabazi
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Brigitte Ilien
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Frédéric Simonin
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France.
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18
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Abstract
This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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19
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Berlinck RGS, Romminger S. The chemistry and biology of guanidine natural products. Nat Prod Rep 2016; 33:456-90. [DOI: 10.1039/c5np00108k] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The present review discusses the isolation, structure determination, synthesis, biosynthesis and biological activities of secondary metabolites bearing a guanidine group.
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Affiliation(s)
| | - Stelamar Romminger
- Instituto de Química de São Carlos
- Universidade de São Paulo
- São Carlos
- Brazil
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20
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Kumarihamy M, León F, Pettaway S, Wilson L, Lambert JA, Wang M, Hill C, McCurdy CR, ElSohly MA, Cutler SJ, Muhammad I. In vitro opioid receptor affinity and in vivo behavioral studies of Nelumbo nucifera flower. JOURNAL OF ETHNOPHARMACOLOGY 2015; 174:57-65. [PMID: 26260436 PMCID: PMC4636954 DOI: 10.1016/j.jep.2015.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/09/2015] [Accepted: 08/06/2015] [Indexed: 06/04/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Nelumbo nucifera Geartn., known as sacred lotus, has been used traditionally in South East Asia as a traditional medicine for various CNS disorders including stress, fever, depression, insomnia, and cognitive conditions. AIM OF THE STUDY To investigate the in vitro cannabinoid and opioid receptor binding affinities, and in vivo behavioral actions of Nelumbo flower extracts and to isolate the potential compounds to treat CNS associated disorders. MATERIALS AND METHODS The white and pink flowers of N. nucifera were extracted with 95% EtOH, followed by acid-base partitioning using CHCl3 to give acidic and basic partitions. These partitions were subjected to Centrifugal Preparative TLC (CPTLC) to yield benzyltetrahydroisoquinoline (BTIQ) alkaloids and long chain fatty acids, identified by physical and spectroscopic methods. In addition, EtOH extracts and partitions were analyzed for chemical markers by UHPLC/MS and GC/MS. In vitro neuropharmacological effects were evaluated by cannabinoid (CB1 and CB2) and opioid [delta (δ), kappa (ĸ), and mu (µ)] competitive radioligand binding and GTPγS functional assays. The in vivo behavioral effect was studied through the use of the mouse tetrad assay at 10, 30, 75 and 100mg/kg/ip doses that revealed the effect on locomotion, catalepsy, body temperature, and nociception of acidic and basic CHCl3 partitions, fractions, and compounds. RESULTS Three aporphines, nuciferine (1), N-nor-nuciferine (2), asimilobine (3), and five BTIQs, armepavine (4), O-methylcoclaurine (5), N-methylcoclaurine (6), coclaurine (7), neferine (10), and a mixture of linoleic and palmitic acids (LA and PA), were identified and evaluated for cannabinoid and opioid receptor displacement activities. Compounds 5-7 showed binding affinities for the ĸ opioid receptor with equilibrium dissociation constant (Ki) values of 3.5 ± 0.3, 0.9 ± 0.1, 2.2 ± 0.2 μM, respectively. Compound 10 displayed affinities for δ-and µ- opioid receptors with Ki values of 0.7 ± 0.1 and 1.8 ± 0.2 μM, respectively, and was determined to be a weak δ agonist by GTPγS functional assay. The mixture of LA and PA (1:1) showed an affinity for δ opioid receptor with a Ki value of 9.2 ± 1.1 μM. The acidic and basic CHCl3 partitions, compounds 1 and 7, and 5-7 mixture were subjected to the tetrad assay, of which the acidic partition displayed decreased locomotion and increased catalepsy, antinociception, and hypothermia in animal at doses of 75-100 mg/kg/ip, and also showed clonic-tonic seizures upon touch at 100mg/kg. CONCLUSION Bioassay-guided isolation revealed compounds 5-7, 10, and the mixture of LA and PA displayed various degrees of opioid receptor radioligand displacement affinities. The in vivo tetrad assay of acidic CHCl3 partition, enriched with aporphines 1 and 2, displayed actions on all four points of behavioral parameters. It can be concluded that the in vivo mild canabimimetic-type effect observed for the CHCl3 partition is likely mediated through other CNS mechanisms since the extracts, partitions, and isolated compounds had no affinity for the in vitro CB1 and CB2 receptors. This work, along with traditional use and the reported bioactivities of the BTIQ alkaloids, suggested further studies on N. nucifera are needed to understand the roles that the extracts and/or individual compounds might contribute to the behavioral effects.
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Affiliation(s)
- Mallika Kumarihamy
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Francisco León
- Department of BioMolecular Sciences, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Sara Pettaway
- Department of BioMolecular Sciences, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Lisa Wilson
- Department of BioMolecular Sciences, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Janet A Lambert
- Department of BioMolecular Sciences, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Mei Wang
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Christopher Hill
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Christopher R McCurdy
- Department of BioMolecular Sciences, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Mahmoud A ElSohly
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA; Department of Pharmaceutics and Drug Delivery, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Stephen J Cutler
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA; Department of BioMolecular Sciences, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA
| | - Ilias Muhammad
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677, USA.
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