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Griffith EY, ElSayed M, Dura-Bernal S, Neymotin SA, Uhlrich DJ, Lytton WW, Zhu JJ. Mechanism of an Intrinsic Oscillation in Rat Geniculate Interneurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.06.597830. [PMID: 38895250 PMCID: PMC11185623 DOI: 10.1101/2024.06.06.597830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Depolarizing current injections produced a rhythmic bursting of action potentials - a bursting oscillation - in a set of local interneurons in the lateral geniculate nucleus (LGN) of rats. The current dynamics underlying this firing pattern have not been determined, though this cell type constitutes an important cellular component of thalamocortical circuitry, and contributes to both pathologic and non-pathologic brain states. We thus investigated the source of the bursting oscillation using pharmacological manipulations in LGN slices in vitro and in silico. 1. Selective blockade of calcium channel subtypes revealed that high-threshold calcium currentsI L andI P contributed strongly to the oscillation. 2. Increased extracellular K+ concentration (decreased K+currents) eliminated the oscillation. 3. Selective blockade of K+ channel subtypes demonstrated that the calcium-sensitive potassium current (I A H P ) was of primary importance. A morphologically simplified, multicompartment model of the thalamic interneuron characterized the oscillation as follows: 1. The low-threshold calcium currentI T provided the strong initial burst characteristic of the oscillation. 2. Alternating fluxes through high-threshold calcium channels andI A H P then provided the continuing oscillation's burst and interburst periods respectively. This interplay betweenI L andI A H P contrasts with the current dynamics underlying oscillations in thalamocortical and reticularis neurons, which primarily involveI T andI H , orI T andI A H P respectively. These findings thus point to a novel electrophysiological mechanism for generating intrinsic oscillations in a major thalamic cell type. Because local interneurons can sculpt the behavior of thalamocortical circuits, these results suggest new targets for the manipulation of ascending thalamocortical network activity.
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Affiliation(s)
- Erica Y Griffith
- Department of Neural and Behavioral Sciences, SUNY Downstate Health Sciences University, Brooklyn, NY
- Center for Biomedical Imaging and Neuromodulation, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY
| | - Mohamed ElSayed
- Department of Psychiatry, Geisel School of Medicine at Dartmouth, Hanover, NH
- Department of Biomedical Engineering, SUNY Downstate School of Graduate Studies, Brooklyn, NY
- Department of Psychiatry, New Hampshire Hospital, Concord, NH
| | - Salvador Dura-Bernal
- Center for Biomedical Imaging and Neuromodulation, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY
- Department of Physiology and Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY
| | - Samuel A Neymotin
- Center for Biomedical Imaging and Neuromodulation, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY
- Department of Psychiatry, New York University School of Medicine, New York, NY
| | - Daniel J Uhlrich
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, USA
| | - William W Lytton
- Department of Physiology and Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY
- Department of Neurology, Kings County Hospital, Brooklyn, NY
| | - J Julius Zhu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA
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Germoush MO, Fouda M, Aly H, Saber I, Alrashdi BM, Massoud D, Alzwain S, Altyar AE, Abdel-Daim MM, Sarhan M. Proteomic analysis of the venom of Conus flavidus from Red Sea reveals potential pharmacological applications. J Genet Eng Biotechnol 2024; 22:100375. [PMID: 38797555 PMCID: PMC11066669 DOI: 10.1016/j.jgeb.2024.100375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 03/15/2024] [Accepted: 03/28/2024] [Indexed: 05/29/2024]
Abstract
BACKGROUND Venomous marine cone snails produce unique neurotoxins called conopeptides or conotoxins, which are valuable for research and drug discovery. Characterizing Conus venom is important, especially for poorly studied species, as these tiny and steady molecules have considerable potential as research tools for detecting new pharmacological applications. In this study, a worm-hunting cone snail, Conus flavidus inhabiting the Red Sea coast were collected, dissected and the venom gland extraction was subjected to proteomic analysis to define the venom composition, and confirm the functional structure of conopeptides. RESULTS Analysis of C. flavidus venom identified 117 peptide fragments and assorted them to conotoxin precursors and non-conotoxin proteins. In this procedure, 65 conotoxin precursors were classified and identified to 16 conotoxin precursors and hormone superfamilies. In the venom of C. flavidus, the four conotoxin superfamilies T, A, O2, and M were the most abundant peptides, accounting for 75.8% of the total conotoxin diversity. Additionally, 19 non-conotoxin proteins were specified in the venom, as well as several potentially biologically active peptides with putative applications. CONCLUSION Our research displayed that the structure of the C. flavidus-derived proteome is similar to other Conus species and includes toxins, ionic channel inhibitors, insulin-like peptides, and hyaluronidase. This study provides a foundation for discovering new conopeptides from C. flavidus venom for pharmaceutical use.
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Affiliation(s)
- Mousa O Germoush
- Biology Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia.
| | - Maged Fouda
- Biology Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia
| | - Hamdy Aly
- Zoology Department, Faculty of Science, Al-Azhar University, Assiut Branch 71524, Assuit, Egypt
| | - Islam Saber
- Zoology Department, Faculty of Science, Al-Azhar University, Assiut Branch 71524, Assuit, Egypt
| | - Barakat M Alrashdi
- Biology Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia
| | - Diaa Massoud
- Biology Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia
| | - Sarah Alzwain
- Biology Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia
| | - Ahmed E Altyar
- Department of Pharmacy Practice, Faculty of Pharmacy, King Abdulaziz University, P.O. Box 80260, Jeddah 21589, Saudi Arabia; Pharmacy Program, Batterjee Medical College, P.O. Box 6231, Jeddah 21442, Saudi Arabia
| | - Mohamed M Abdel-Daim
- Department of Pharmaceutical Sciences, Pharmacy Program, Batterjee Medical College, P.O. Box 6231, Jeddah 21442, Saudi Arabia; Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Moustafa Sarhan
- Zoology Department, Faculty of Science, Al-Azhar University, Assiut Branch 71524, Assuit, Egypt; Department of Biomedical Sciences, College of Clinical Pharmacy, King Faisal University, 31982, Saudi Arabia
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Gach-Janczak K, Biernat M, Kuczer M, Adamska-Bartłomiejczyk A, Kluczyk A. Analgesic Peptides: From Natural Diversity to Rational Design. Molecules 2024; 29:1544. [PMID: 38611824 PMCID: PMC11013236 DOI: 10.3390/molecules29071544] [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: 02/08/2024] [Revised: 03/24/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
Pain affects one-third of the global population and is a significant public health issue. The use of opioid drugs, which are the strongest painkillers, is associated with several side effects, such as tolerance, addiction, overdose, and even death. An increasing demand for novel, safer analgesic agents is a driving force for exploring natural sources of bioactive peptides with antinociceptive activity. Since the G protein-coupled receptors (GPCRs) play a crucial role in pain modulation, the discovery of new peptide ligands for GPCRs is a significant challenge for novel drug development. The aim of this review is to present peptides of human and animal origin with antinociceptive potential and to show the possibilities of their modification, as well as the design of novel structures. The study presents the current knowledge on structure-activity relationship in the design of peptide-based biomimetic compounds, the modification strategies directed at increasing the antinociceptive activity, and improvement of metabolic stability and pharmacodynamic profile. The procedures employed in prolonged drug delivery of emerging compounds are also discussed. The work summarizes the conditions leading to the development of potential morphine replacements.
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Affiliation(s)
- Katarzyna Gach-Janczak
- Department of Biomolecular Chemistry, Faculty of Medicine, Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland; (K.G.-J.); (A.A.-B.)
| | - Monika Biernat
- Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland; (M.B.); (M.K.)
| | - Mariola Kuczer
- Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland; (M.B.); (M.K.)
| | - Anna Adamska-Bartłomiejczyk
- Department of Biomolecular Chemistry, Faculty of Medicine, Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland; (K.G.-J.); (A.A.-B.)
| | - Alicja Kluczyk
- Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland; (M.B.); (M.K.)
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Choudhary S, Kaur R, Waziri A, Garg A, Kadian R, Alam MS. N-type calcium channel blockers: a new approach towards the treatment of chronic neuropathic pain. EXPLORATION OF MEDICINE 2023. [DOI: 10.37349/emed.2023.00126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
Neuropathic pain (NP) remains maltreated for a wide number of patients by the currently available treatments and little research has been done in finding new drugs for treating NP. Ziconotide (PrialtTM) had been developed as the new drug, which belongs to the class of ω-conotoxin MVIIA. It inhibits N-type calcium channels. Ziconotide is under the last phase of the clinical trial, a new non-narcotic drug for the management of NP. Synthetically it has shown the similarities with ω-conotoxin MVIIA, a constituent of poison found in fish hunting snails (Conus magus). Ziconotide acts by selectively blocking neural N-type voltage-sensitized Ca2+ channels (NVSCCs). Certain herbal drugs also have been studied but no clinical result is there and the study is only limited to preclinical data. This review emphasizes the N-type calcium channel inhibitors, and their mechanisms for blocking calcium channels with their remedial prospects for treating chronic NP.
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Affiliation(s)
- Shikha Choudhary
- School of Medical and Allied Sciences, K.R. Mangalam University, Gurugram 122103, Haryana, India
| | - Raminderjit Kaur
- School of Medical and Allied Sciences, K.R. Mangalam University, Gurugram 122103, Haryana, India
| | - Aafrin Waziri
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Delhi, 110078, India
| | - Arun Garg
- Department of Pharmacology, NIMS Institute of Pharmacy, NIMS University, Jaipur 303121, Rajasthan, India
| | - Renu Kadian
- Ram Gopal College of Pharmacy, Gurugram 122506, Haryana, India
| | - Md Sabir Alam
- SGT College of Pharmacy, SGT University, Gurugram 122505, Haryana, India
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5
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Role of voltage-sensitive Ca 2+ channels in the in vivo dopamine release induced by the organophosphorus pesticide glufosinate ammonium in rat striatum. Toxicol Lett 2022; 373:105-113. [PMID: 36427774 DOI: 10.1016/j.toxlet.2022.11.012] [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: 05/11/2022] [Revised: 10/05/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022]
Abstract
The possible role of voltage-sensitive calcium channels (VSCC) activation in the glufosinate ammonium (GLA)-induced dopamine release was investigated using selective VSCC blockers and the dopamine levels were measured by HPLC from samples obtained by in vivo cerebral microdialysis. While pretreatment with 10 μM flunarizine (T-type VSCC antagonist) or nicardipine (L-type VSCC antagonist) had no statistically significant effect on dopamine release induced by 10 mM GLA, pretreatment with 100 μM of both antagonists, or 20 μM ω-conotoxin MVIIC (non-selective P/Q-type VSCC antagonist) significantly decreased the GLA-induced dopamine release over 72.2%, 73%, and 70.2%, respectively. Administration of the specific antagonist of neuronal N-type VSCCs, the ω-conotoxin GVIA (20 μM), produced an almost complete blockade of in vivo dopamine release induced by GLA. These results show that GLA-induced dopamine release could be produced by the activation of a wide range of striatal VSCC located at the synaptic terminals and axons of striatal dopaminergic neurons, especially N-type VSCC.
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Hasan MM, Starobova H, Mueller A, Vetter I, Lewis RJ. Subcutaneous ω-Conotoxins Alleviate Mechanical Pain in Rodent Models of Acute Peripheral Neuropathy. Mar Drugs 2021; 19:106. [PMID: 33670311 PMCID: PMC7917901 DOI: 10.3390/md19020106] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 02/05/2021] [Accepted: 02/07/2021] [Indexed: 11/16/2022] Open
Abstract
The peripheral effects of ω-conotoxins, selective blockers of N-type voltage-gated calcium channels (CaV2.2), have not been characterised across different clinically relevant pain models. This study examines the effects of locally administered ω-conotoxin MVIIA, GVIA, and CVIF on mechanical and thermal paw withdrawal threshold (PWT) in postsurgical pain (PSP), cisplatin-induced neuropathy (CisIPN), and oxaliplatin-induced neuropathy (OIPN) rodent models. Intraplantar injection of 300, 100 and 30 nM MVIIA significantly (p < 0.0001, p < 0.0001, and p < 0.05, respectively) alleviated mechanical allodynia of mice in PSP model compared to vehicle control group. Similarly, intraplantar injection of 300, 100, and 30 nM MVIIA (p < 0.0001, p < 0.01, and p < 0.05, respectively), and 300 nM and 100 nM GVIA (p < 0.0001 and p < 0.05, respectively) significantly increased mechanical thresholds of mice in OIPN model. The ED50 of GVIA and MVIIA in OIPN was found to be 1.8 pmol/paw and 0.8 pmol/paw, respectively. However, none of the ω-conotoxins were effective in a mouse model of CisIPN. The intraplantar administration of 300 nM GVIA, MVIIA, and CVIF did not cause any locomotor side effects. The intraplantar administration of MVIIA can alleviate incision-induced mechanical allodynia, and GVIA and MVIIA effectively reduce OIPN associated mechanical pain, without locomotor side effects, in rodent models. In contrast, CVIF was inactive in these pain models, suggesting it is unable to block a subset of N-type voltage-gated calcium channels associated with nociceptors in the skin.
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Affiliation(s)
- Md. Mahadhi Hasan
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia; (M.M.H.); (H.S.); (A.M.); (I.V.)
| | - Hana Starobova
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia; (M.M.H.); (H.S.); (A.M.); (I.V.)
| | - Alexander Mueller
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia; (M.M.H.); (H.S.); (A.M.); (I.V.)
| | - Irina Vetter
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia; (M.M.H.); (H.S.); (A.M.); (I.V.)
- School of Pharmacy, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Richard J. Lewis
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia; (M.M.H.); (H.S.); (A.M.); (I.V.)
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7
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Sameera, Shah FA, Rashid S. Conformational ensembles of non-peptide ω-conotoxin mimetics and Ca +2 ion binding to human voltage-gated N-type calcium channel Ca v2.2. Comput Struct Biotechnol J 2020; 18:2357-2372. [PMID: 32994894 PMCID: PMC7498737 DOI: 10.1016/j.csbj.2020.08.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/24/2020] [Accepted: 08/26/2020] [Indexed: 02/07/2023] Open
Abstract
Chronic neuropathic pain is the most complex and challenging clinical problem of a population that sets a major physical and economic burden at the global level. Ca2+-permeable channels functionally orchestrate the processing of pain signals. Among them, N-type voltage-gated calcium channels (VGCC) hold prominent contribution in the pain signal transduction and serve as prime targets for synaptic transmission block and attenuation of neuropathic pain. Here, we present detailed in silico analysis to comprehend the underlying conformational changes upon Ca2+ ion passage through Cav2.2 to differentially correlate subtle transitions induced via binding of a conopeptide-mimetic alkylphenyl ether-based analogue MVIIA. Interestingly, pronounced conformational changes were witnessed at the proximal carboxyl-terminus of Cav2.2 that attained an upright orientation upon Ca+2 ion permeability. Moreover, remarkable changes were observed in the architecture of channel tunnel. These findings illustrate that inhibitor binding to Cav2.2 may induce more narrowing in the pore size as compared to Ca2+ binding through modulating the hydrophilicity pattern at the selectivity region. A significant reduction in the tunnel volume at the selectivity filter and its enhancement at the activation gate of Ca+2-bound Cav2.2 suggests that ion binding modulates the outward splaying of pore-lining S6 helices to open the voltage gate. Overall, current study delineates dynamic conformational ensembles in terms of Ca+2 ion and MVIIA-associated structural implications in the Cav2.2 that may help in better therapeutic intervention to chronic and neuropathic pain management.
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Affiliation(s)
- Sameera
- National Center for Bioinformatics, Quaid-i-Azam University, Islamabad, Pakistan
| | - Fawad Ali Shah
- Riphah Institute of Pharmaceutical Sciences, Riphah International University, Islamabad, Pakistan
| | - Sajid Rashid
- National Center for Bioinformatics, Quaid-i-Azam University, Islamabad, Pakistan
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8
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Conotoxins as Tools to Understand the Physiological Function of Voltage-Gated Calcium (Ca V) Channels. Mar Drugs 2017; 15:md15100313. [PMID: 29027927 PMCID: PMC5666421 DOI: 10.3390/md15100313] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 09/06/2017] [Accepted: 10/04/2017] [Indexed: 12/29/2022] Open
Abstract
Voltage-gated calcium (CaV) channels are widely expressed and are essential for the completion of multiple physiological processes. Close regulation of their activity by specific inhibitors and agonists become fundamental to understand their role in cellular homeostasis as well as in human tissues and organs. CaV channels are divided into two groups depending on the membrane potential required to activate them: High-voltage activated (HVA, CaV1.1–1.4; CaV2.1–2.3) and Low-voltage activated (LVA, CaV3.1–3.3). HVA channels are highly expressed in brain (neurons), heart, and adrenal medulla (chromaffin cells), among others, and are also classified into subtypes which can be distinguished using pharmacological approaches. Cone snails are marine gastropods that capture their prey by injecting venom, “conopeptides”, which cause paralysis in a few seconds. A subset of conopeptides called conotoxins are relatively small polypeptides, rich in disulfide bonds, that target ion channels, transporters and receptors localized at the neuromuscular system of the animal target. In this review, we describe the structure and properties of conotoxins that selectively block HVA calcium channels. We compare their potency on several HVA channel subtypes, emphasizing neuronal calcium channels. Lastly, we analyze recent advances in the therapeutic use of conotoxins for medical treatments.
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Tietze D, Leipold E, Heimer P, Böhm M, Winschel W, Imhof D, Heinemann SH, Tietze AA. Molecular interaction of δ-conopeptide EVIA with voltage-gated Na+ channels. Biochim Biophys Acta Gen Subj 2016; 1860:2053-63. [DOI: 10.1016/j.bbagen.2016.06.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/02/2016] [Accepted: 06/12/2016] [Indexed: 12/19/2022]
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Bioactive Mimetics of Conotoxins and other Venom Peptides. Toxins (Basel) 2015; 7:4175-98. [PMID: 26501323 PMCID: PMC4626728 DOI: 10.3390/toxins7104175] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/08/2015] [Indexed: 11/17/2022] Open
Abstract
Ziconotide (Prialt®), a synthetic version of the peptide ω-conotoxin MVIIA found in the venom of a fish-hunting marine cone snail Conus magnus, is one of very few drugs effective in the treatment of intractable chronic pain. However, its intrathecal mode of delivery and narrow therapeutic window cause complications for patients. This review will summarize progress in the development of small molecule, non-peptidic mimics of Conotoxins and a small number of other venom peptides. This will include a description of how some of the initially designed mimics have been modified to improve their drug-like properties.
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Mohammadi SA, Christie MJ. Conotoxin Interactions with α9α10-nAChRs: Is the α9α10-Nicotinic Acetylcholine Receptor an Important Therapeutic Target for Pain Management? Toxins (Basel) 2015; 7:3916-32. [PMID: 26426047 PMCID: PMC4626711 DOI: 10.3390/toxins7103916] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 09/14/2015] [Accepted: 09/18/2015] [Indexed: 11/16/2022] Open
Abstract
The α9α10-nicotinic acetylcholine receptor (nAChR) has been implicated in pain and has been proposed to be a novel target for analgesics. However, the evidence to support the involvement of the α9α10-nAChR in pain is conflicted. This receptor was first implicated in pain with the characterisation of conotoxin Vc1.1, which is highly selective for α9α10-nAChRs and is an efficacious analgesic in chronic pain models with restorative capacities and no reported side effects. Numerous other analgesic conotoxin and non-conotoxin molecules have been subsequently characterised that also inhibit α9α10-nAChRs. However, there is evidence that α9α10-nAChR inhibition is neither necessary nor sufficient for analgesia. α9α10-nAChR-inhibiting analogues of Vc1.1 have no analgesic effects. Genetically-modified α9-nAChR knockout mice have a phenotype that is markedly different from the analgesic profile of Vc1.1 and similar conotoxins, suggesting that the conotoxin effects are largely independent of α9α10-nAChRs. Furthermore, an alternative mechanism of analgesia by Vc1.1 and other similar conotoxins involving non-canonical coupling of GABAB receptors to voltage-gated calcium channels is known. Additional incongruities regarding α9α10-nAChRs in analgesia are discussed. A more comprehensive characterisation of the role of α9α10-nAChRs in pain is crucial for understanding the analgesic action of conotoxins and for improved drug design.
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Affiliation(s)
- Sarasa A Mohammadi
- Discipline of Pharmacology, the University of Sydney, Sydney, NSW 2006, Australia.
| | - MacDonald J Christie
- Discipline of Pharmacology, the University of Sydney, Sydney, NSW 2006, Australia.
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Mollica A, Costante R, Novellino E, Stefanucci A, Pieretti S, Zador F, Samavati R, Borsodi A, Benyhe S, Vetter I, Lewis RJ. Design, Synthesis and Biological Evaluation of Two Opioid Agonist and Cav2.2 Blocker Multitarget Ligands. Chem Biol Drug Des 2014; 86:156-62. [DOI: 10.1111/cbdd.12479] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 09/26/2014] [Accepted: 11/07/2014] [Indexed: 12/01/2022]
Affiliation(s)
- Adriano Mollica
- Dipartimento di Farmacia; Università di Chieti-Pescara “G. d'Annunzio”; Via dei Vestini 31 66100 Chieti Italy
| | - Roberto Costante
- Dipartimento di Farmacia; Università di Chieti-Pescara “G. d'Annunzio”; Via dei Vestini 31 66100 Chieti Italy
| | - Ettore Novellino
- Dipartimento di Farmacia; Università di Napoli “Federico II”; Via D. Montesano, 49 80131 Naples Italy
| | - Azzurra Stefanucci
- Dipartimento di Chimica, Sapienza; Università di Roma; P.le A. Moro 5 00187 Rome Italy
| | - Stefano Pieretti
- Department of Therapeutic Research and Medicine Evaluation; Istituto Superiore di Sanità; V.le Regina Elena 299 00161 Rome Italy
| | - Ferenc Zador
- Institute of Biochemistry; Biological Research Centre; Hungarian Academy of Sciences; 6726 Szeged Hungary
| | - Reza Samavati
- Institute of Biochemistry; Biological Research Centre; Hungarian Academy of Sciences; 6726 Szeged Hungary
| | - Anna Borsodi
- Institute of Biochemistry; Biological Research Centre; Hungarian Academy of Sciences; 6726 Szeged Hungary
| | - Sándor Benyhe
- Institute of Biochemistry; Biological Research Centre; Hungarian Academy of Sciences; 6726 Szeged Hungary
| | - Irina Vetter
- Institute for Molecular Bioscience; The University of Queensland; Brisbane St Lucia Qld 4072 Australia
| | - Richard J. Lewis
- Institute for Molecular Bioscience; The University of Queensland; Brisbane St Lucia Qld 4072 Australia
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Expression and pharmacology of endogenous Cav channels in SH-SY5Y human neuroblastoma cells. PLoS One 2013; 8:e59293. [PMID: 23536870 PMCID: PMC3607609 DOI: 10.1371/journal.pone.0059293] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Accepted: 02/13/2013] [Indexed: 12/24/2022] Open
Abstract
SH-SY5Y human neuroblastoma cells provide a useful in vitro model to study the mechanisms underlying neurotransmission and nociception. These cells are derived from human sympathetic neuronal tissue and thus, express a number of the Cav channel subtypes essential for regulation of important physiological functions, such as heart contraction and nociception, including the clinically validated pain target Cav2.2. We have detected mRNA transcripts for a range of endogenous expressed subtypes Cav1.3, Cav2.2 (including two Cav1.3, and three Cav2.2 splice variant isoforms) and Cav3.1 in SH-SY5Y cells; as well as Cav auxiliary subunits α2δ1–3, β1, β3, β4, γ1, γ4–5, and γ7. Both high- and low-voltage activated Cav channels generated calcium signals in SH-SY5Y cells. Pharmacological characterisation using ω-conotoxins CVID and MVIIA revealed significantly (∼ 10-fold) higher affinity at human versus rat Cav2.2, while GVIA, which interacts with Cav2.2 through a distinct pharmacophore had similar affinity for both species. CVID, GVIA and MVIIA affinity was higher for SH-SY5Y membranes vs whole cells in the binding assays and functional assays, suggesting auxiliary subunits expressed endogenously in native systems can strongly influence Cav2.2 channels pharmacology. These results may have implications for strategies used to identify therapeutic leads at Cav2.2 channels.
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Vink S, Alewood PF. Targeting voltage-gated calcium channels: developments in peptide and small-molecule inhibitors for the treatment of neuropathic pain. Br J Pharmacol 2013; 167:970-89. [PMID: 22725651 DOI: 10.1111/j.1476-5381.2012.02082.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Chronic pain affects approximately 20% of people worldwide and places a large economic and social burden on society. Despite the availability of a range of analgesics, this condition is inadequately treated, with complete alleviation of symptoms rarely occurring. In the past 30 years, the voltage-gated calcium channels (VGCCs) have been recognized as potential targets for analgesic development. Although the majority of the research has been focused on Ca(v) 2.2 in particular, other VGCC subtypes such as Ca(v) 3.2 have recently come to the forefront of analgesic research. Venom peptides from marine cone snails have been proven to be a valuable tool in neuroscience, playing a major role in the identification and characterization of VGCC subtypes and producing the first conotoxin-based drug on the market, the ω-conotoxin, ziconotide. This peptide potently and selectively inhibits Ca(v) 2.2, resulting in analgesia in chronic pain states. However, this drug is only available via intrathecal administration, and adverse effects and a narrow therapeutic window have limited its use in the clinic. Other Ca(v) 2.2 inhibitors are currently in development and offer the promise of an improved route of administration and safety profile. This review assesses the potential of targeting VGCCs for analgesic development, with a main focus on conotoxins that block Ca(v) 2.2 and the developments made to transform them into therapeutics.
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Affiliation(s)
- S Vink
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
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Abstract
Conopeptides from the venoms of marine snails have attracted much interest as leads in drug design. Currently, one drug, Prialt(®), is on the market as a treatment for chronic neuropathic pain. Conopeptides target a range of ion channels, receptors and transporters, and are typically small, relatively stable peptides that are generally amenable to production using solid-phase peptide synthesis. With only a small fraction of the predicted diversity of conopeptides examined so far, these peptides represent an exciting and largely untapped resource for drug discovery. Recent efforts at chemically re-engineering conopeptides to improve their biopharmaceutical properties promise to accelerate the translation of these fascinating marine peptides to the clinic.
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Yamamoto T, Niwa S, Tokumasu M, Onishi T, Ohno S, Hagihara M, Koganei H, Fujita SI, Takeda T, Saitou Y, Iwayama S, Takahara A, Iwata S, Shoji M. Discovery and evaluation of selective N-type calcium channel blockers: 6-Unsubstituted-1,4-dihydropyridine-5-carboxylic acid derivatives. Bioorg Med Chem Lett 2012; 22:3639-42. [DOI: 10.1016/j.bmcl.2012.04.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Revised: 04/06/2012] [Accepted: 04/10/2012] [Indexed: 11/29/2022]
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Schroeder CI, Nielsen KJ, Adams DA, Loughnan M, Thomas L, Alewood PF, Lewis RJ, Craik DJ. Effects of Lys2 to Ala2 substitutions on the structure and potency of ω-conotoxins MVIIA and CVID. Biopolymers 2012. [DOI: 10.1002/bip.22031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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18
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András CD, Albert C, Salamon S, Gálicza J, András R, András E. Conus magus vs. Irukandji syndrome: A computational approach of a possible new therapy. Brain Res Bull 2011; 86:195-202. [DOI: 10.1016/j.brainresbull.2011.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2011] [Revised: 07/03/2011] [Accepted: 07/05/2011] [Indexed: 01/22/2023]
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Blunt JW, Copp BR, Hu WP, Munro MHG, Northcote PT, Prinsep MR. Marine natural products. Nat Prod Rep 2008; 25:35-94. [PMID: 18250897 DOI: 10.1039/b701534h] [Citation(s) in RCA: 284] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This review covers the literature published in 2006 for marine natural products, with 758 citations (534 for the period January to December 2006) referring to compounds isolated from marine microorganisms and phytoplankton, green algae, brown algae, red algae, sponges, cnidaria, bryozoans, molluscs, tunicates and echinoderms. The emphasis is on new compounds (779 for 2006), together with their relevant biological activities, source organisms and country of origin. Biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.
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Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
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