1
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Gary S, Roy A, Bloom S. Carbocyclic setmelanotide analogs maintain biochemical potency at melanocortin 4 receptors. J Pept Sci 2024:e3656. [PMID: 39394922 DOI: 10.1002/psc.3656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2024] [Revised: 09/20/2024] [Accepted: 09/23/2024] [Indexed: 10/14/2024]
Abstract
The melanocortin 4 receptor (MC4R) plays a critical role in satiety and energy homeostasis, and its dysregulation is implicated in numerous hyperphagic and obese disease states. Setmelanotide, a disulfide-based cyclic peptide, can rescue MC4R activity and treat obesities caused by genetic defects in MC4R signaling. But this peptide has moderate blood-brain barrier penetrance and metabolic stability, which can limit its efficacy in practice. Based on the cryo-electron microscopy structure of setmelanotide-bound MC4R, we hypothesized that replacing its lone disulfide bond with more metabolically stable and permeability-enhancing carbon-based linker groups could improve pharmacokinetic properties without abolishing activity. To test this, we used chemistry developed by our lab to prepare 11 carbocyclic (alkyl, aryl, perfluoroalkyl, and ethereal) analogs of setmelanotide and determined their biochemical potencies at MC4R in vitro. Ten analogs displayed full agonism, showing that disulfide replacement is tolerant of linkers ranging in size, rigidity, and functional groups, with heteroatom- or aryl-rich linkers displaying superior potencies.
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Affiliation(s)
- Samuel Gary
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, USA
| | - Anuradha Roy
- High Throughput Screening Laboratory, University of Kansas, Lawrence, Kansas, USA
| | - Steven Bloom
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, USA
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2
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Trotta AM, Mazzarella V, Roggia M, D'Aniello A, Del Bene A, Vetrei C, Di Maiolo G, Campagna E, Natale B, Rea G, Santagata S, D'Alterio C, Cutolo R, Mottola S, Merlino F, Benedetti R, Altucci L, Messere A, Cosconati S, Tomassi S, Scala S, Di Maro S. Comprehensive structural investigation of a potent and selective CXCR4 antagonist via crosslink modification. Eur J Med Chem 2024; 279:116911. [PMID: 39348763 DOI: 10.1016/j.ejmech.2024.116911] [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: 07/21/2024] [Revised: 09/23/2024] [Accepted: 09/23/2024] [Indexed: 10/02/2024]
Abstract
Macrocyclization presents a valuable strategy for enhancing the pharmacokinetic and pharmacodynamic profiles of short bioactive peptides. The exploration of various macrocyclic characteristics, such as crosslinking tethers, ring size, and orientation, is generally conducted during the early stages of development. Herein, starting from a potent and selective C-X-C chemokine receptor 4 (CXCR4) cyclic heptapeptide antagonist mimicking the N-terminal region of CXCL12, we demonstrated that the disulfide bridge could be successfully replaced with a side-chain to side-chain lactam bond, which is commonly not enlisted among the conventional disulfide mimetics. An extensive investigation was carried out to explore the chemical space of the resulting peptides, including macrocyclization width, stereochemical configuration, and lactam orientation, all of which were correlated with biochemical activity. We identified a novel heptapeptide that fully replicates the pharmacological profile of the parent peptide on CXCR4, including its potency, selectivity, and antagonistic activity, while demonstrating enhanced stability in a reductive environment. At this stage, computational studies were instructed to shed light on how the lactam cyclization features influenced the overall structure of 21 and, in turn, its ability to interact with the receptor. We envisage that these findings can give new momentum to the use of lactam cyclization as a disulfide bond mimetic and contribute to the enhancement of the repertoire for peptide-based drug development, thereby paving the way for novel avenues in therapeutic innovation.
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Affiliation(s)
- Anna Maria Trotta
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy
| | - Vincenzo Mazzarella
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Michele Roggia
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Antonia D'Aniello
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Alessandra Del Bene
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Cinzia Vetrei
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy
| | - Gaetana Di Maiolo
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy
| | - Erica Campagna
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Benito Natale
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Giuseppina Rea
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy
| | - Sara Santagata
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy
| | - Crescenzo D'Alterio
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy
| | - Roberto Cutolo
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Salvatore Mottola
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Francesco Merlino
- Department of Pharmacy, University of Naples "Federico II", 80131, Naples, Italy
| | - Rosaria Benedetti
- Department of Precision Medicine, University of Campania ''Luigi Vanvitelli'', Vico L. De Crecchio 7, 80138, Naples, Italy; Program of Medical Epigenetics, Vanvitelli Hospital, Naples, Italy
| | - Lucia Altucci
- Department of Precision Medicine, University of Campania ''Luigi Vanvitelli'', Vico L. De Crecchio 7, 80138, Naples, Italy; Program of Medical Epigenetics, Vanvitelli Hospital, Naples, Italy; Institute of Endocrinology and Oncology "Gaetano Salvatore" (IEOS), 80131, Naples, Italy; Biogem Institute of Molecular and Genetic Biology, 83031, Ariano Irpino, Italy
| | - Anna Messere
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Sandro Cosconati
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy
| | - Stefano Tomassi
- Department of Life Science, Health, and Health Professions, LINK Campus University, Via del Casale di San Pio V, 44, 00165, Rome, Italy.
| | - Stefania Scala
- Microenvironment Molecular Targets, Istituto Nazionale per lo Studio e la Cura dei Tumori-IRCCS-Fondazione "G. Pascale", 80131, Naples, Italy.
| | - Salvatore Di Maro
- Department of Environmental, Biological and Pharmaceutical Science and Technology, University of Campania "Luigi Vanvitelli", Via A. Vivaldi, 43, 81100, Caserta, Italy.
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3
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Sun X, Hu J, Ren M, Chang H, Zhangsun D, Zhang B, Dong S. Stapling Cysteine[2,4] Disulfide Bond of α-Conotoxin LsIA and Its Potential in Target Delivery. Mar Drugs 2024; 22:314. [PMID: 39057423 PMCID: PMC11278161 DOI: 10.3390/md22070314] [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: 06/15/2024] [Revised: 07/11/2024] [Accepted: 07/13/2024] [Indexed: 07/28/2024] Open
Abstract
α-Conotoxins, as selective nAChR antagonists, can be valuable tools for targeted drug delivery and fluorescent labeling, while conotoxin-drug or conotoxin-fluorescent conjugates through the disulfide bond are rarely reported. Herein, we demonstrate the [2,4] disulfide bond of α-conotoxin as a feasible new chemical modification site. In this study, analogs of the α-conotoxin LsIA cysteine[2,4] were synthesized by stapling with five linkers, and their inhibitory activities against human α7 and rat α3β2 nAChRs were maintained. To further apply this method in targeted delivery, the alkynylbenzyl bromide linker was synthesized and conjugated with Coumarin 120 (AMC) and Camptothecin (CPT) by copper-catalyzed click chemistry, and then stapled between cysteine[2,4] of the LsIA to construct a fluorescent probe and two peptide-drug conjugates. The maximum emission wavelength of the LsIA fluorescent probe was 402.2 nm, which was essentially unchanged compared with AMC. The cytotoxic activity of the LsIA peptide-drug conjugates on human A549 was maintained in vitro. The results demonstrate that the stapling of cysteine[2,4] with alkynylbenzyl bromide is a simple and feasible strategy for the exploitation and utilization of the α-conotoxin LsIA.
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Affiliation(s)
- Xin Sun
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (X.S.); (J.H.); (M.R.); (D.Z.)
| | - Jiangnan Hu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (X.S.); (J.H.); (M.R.); (D.Z.)
| | - Maomao Ren
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (X.S.); (J.H.); (M.R.); (D.Z.)
| | - Hong Chang
- Hainan Academy of Inspection and Testing, Haikou 570228, China;
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (X.S.); (J.H.); (M.R.); (D.Z.)
| | - Baojian Zhang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (X.S.); (J.H.); (M.R.); (D.Z.)
| | - Shuai Dong
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (X.S.); (J.H.); (M.R.); (D.Z.)
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4
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Thomson AL, Robinson AJ, Belgi A. Synthesis of Cystine-Stabilised Dicarba Conotoxin EpI: Ring-Closing Metathesis of Sidechain Deprotected, Sulfide-Rich Sequences. Mar Drugs 2023; 21:390. [PMID: 37504921 PMCID: PMC10381330 DOI: 10.3390/md21070390] [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: 05/31/2023] [Revised: 06/22/2023] [Accepted: 06/27/2023] [Indexed: 07/29/2023] Open
Abstract
Recombinant peptide synthesis allows for large-scale production of peptides with therapeutic potential. However, access to dicarba peptidomimetics via sidechain-deprotected sequences becomes challenging with exposed Lewis basicity presented by amine and sulfur-containing residues. Presented here is a combination of strategies which can be used to deactivate coordinative residues and achieve high-yielding Ru-catalyzed ring-closing metathesis. The chemistry is exemplified using α-conotoxin EpI, a native bicyclic disulfide-containing sequence isolated from the marine conesnail Conus episcopatus. Replacement of the loop I disulfide with E/Z-dicarba bridges was achieved with high conversion via solution-phase ring-closing metathesis of the unprotected linear peptide after simple chemoselective oxidation and ion-exchange masking of problematic functionality. Metathesis was also attempted in green solvent choices to further improve the sustainability of dicarba peptide synthesis.
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Affiliation(s)
- Amy L Thomson
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Andrea J Robinson
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Alessia Belgi
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
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5
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Giraudo A, Pallavicini M, Bolchi C. Small molecule ligands for α9* and α7 nicotinic receptors: a survey and an update, respectively. Pharmacol Res 2023; 193:106801. [PMID: 37236412 DOI: 10.1016/j.phrs.2023.106801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023]
Abstract
The α9- and α7-containing nicotinic acetylcholine receptors (nAChRs) mediate numerous physiological and pathological processes by complex mechanisms that are currently the subject of intensive study and debate. In this regard, selective ligands serve as invaluable investigative tools and, in many cases, potential therapeutics for the treatment of various CNS disfunctions and diseases, neuropathic pain, inflammation, and cancer. However, the present scenario differs significantly between the two aforementioned nicotinic subtypes. Over the past few decades, a large number of selective α7-nAChR ligands, including full, partial and silent agonists, antagonists, and allosteric modulators, have been described and reviewed. Conversely, reports on selective α9-containing nAChR ligands are relatively scarce, also due to a more recent characterization of this receptor subtype, and hardly any focusing on small molecules. In this review, we focus on the latter, providing a comprehensive overview, while providing only an update over the last five years for α7-nAChR ligands.
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Affiliation(s)
- Alessandro Giraudo
- Department of Pharmaceutical Sciences, University of Milan, via Mangiagalli 25, I-20133 Milano, Italy
| | - Marco Pallavicini
- Department of Pharmaceutical Sciences, University of Milan, via Mangiagalli 25, I-20133 Milano, Italy
| | - Cristiano Bolchi
- Department of Pharmaceutical Sciences, University of Milan, via Mangiagalli 25, I-20133 Milano, Italy.
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6
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Mansbach R, Patel LA, Watson NA, Kubicek-Sutherland JZ, Gnanakaran S. Inferring Pathways of Oxidative Folding from Prefolding Free Energy Landscapes of Disulfide-Rich Toxins. J Phys Chem B 2023; 127:1689-1703. [PMID: 36791259 PMCID: PMC9987446 DOI: 10.1021/acs.jpcb.2c07124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/07/2022] [Indexed: 02/17/2023]
Abstract
Short, cysteine-rich peptides can exist in stable or metastable structural ensembles due to the number of possible patterns of formation of their disulfide bonds. One interesting subset of this peptide group is the conotoxins, which are produced by aquatic snails in the family Conidae. The μ conotoxins, which are antagonists and blockers of the voltage-gated sodium channel, exist in a folding spectrum: on one end of the spectrum are more hirudin-like folders, which form disulfide bonds and then reshuffle them, leading to an ensemble of kinetically trapped isomers, and on the other end are more BPTI-like folders, which form the native disulfide bonds one by one in a particular order, leading to a preponderance of conformations existing in a single stable state. In this Article, we employ the composite diffusion map approach to study the unified free energy surface of prefolding μ-conotoxin equilibrium. We identify the two most important nonlinear collective modes of the unified folding landscape and demonstrate that in the absence of their disulfides, the conotoxins can be thought of as largely disordered polymers. A small increase in the number of hydrophobic residues in the protein shifts the free energy landscape toward hydrophobically collapsed coil conformations responsible for cysteine proximity in hirudin-like folders, compared to semiextended coil conformations with more distal cysteines in BPTI-like folders. Overall, this work sheds important light on the folding processes and free energy landscapes of cysteine-rich peptides and demonstrates the extent to which sequence and length contribute to these landscapes.
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Affiliation(s)
| | - Lara A. Patel
- OpenEye
Scientific Research, Santa Fe, New Mexico 87508, United States
| | - Natalya A. Watson
- Physics
Department, University of Concordia, Montreal, QC H4B 1R6, Canada
| | | | - S. Gnanakaran
- Physical
Chemistry and Applied Spectroscopy Group, Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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7
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Margiotta F, Micheli L, Ciampi C, Ghelardini C, McIntosh JM, Di Cesare Mannelli L. Conus regius-Derived Conotoxins: Novel Therapeutic Opportunities from a Marine Organism. Mar Drugs 2022; 20:773. [PMID: 36547920 PMCID: PMC9783627 DOI: 10.3390/md20120773] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/03/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022] Open
Abstract
Conus regius is a marine venomous mollusk of the Conus genus that captures its prey by injecting a rich cocktail of bioactive disulfide bond rich peptides called conotoxins. These peptides selectively target a broad range of ion channels, membrane receptors, transporters, and enzymes, making them valuable pharmacological tools and potential drug leads. C. regius-derived conotoxins are particularly attractive due to their marked potency and selectivity against specific nicotinic acetylcholine receptor subtypes, whose signalling is involved in pain, cognitive disorders, drug addiction, and cancer. However, the species-specific differences in sensitivity and the low stability and bioavailability of these conotoxins limit their clinical development as novel therapeutic agents for these disorders. Here, we give an overview of the main pharmacological features of the C. regius-derived conotoxins described so far, focusing on the molecular mechanisms underlying their potential therapeutic effects. Additionally, we describe adoptable chemical engineering solutions to improve their pharmacological properties for future potential clinical translation.
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Affiliation(s)
- Francesco Margiotta
- Department of Neuroscience, Psychology, Drug Research and Child Health—NEUROFARBA, Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
| | - Laura Micheli
- Department of Neuroscience, Psychology, Drug Research and Child Health—NEUROFARBA, Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
| | - Clara Ciampi
- Department of Neuroscience, Psychology, Drug Research and Child Health—NEUROFARBA, Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
| | - Carla Ghelardini
- Department of Neuroscience, Psychology, Drug Research and Child Health—NEUROFARBA, Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
| | - J. Michael McIntosh
- George E. Wohlen Veterans Affairs Medical Center, Salt Lake City, UT 84148, USA
- Department of Psychiatry, University of Utah, Salt Lake City, UT 84108, USA
- School of Biological Sciences University of Utah, Salt Lake City, UT 84112, USA
| | - Lorenzo Di Cesare Mannelli
- Department of Neuroscience, Psychology, Drug Research and Child Health—NEUROFARBA, Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
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A Single Amino Acid Replacement Boosts the Analgesic Activity of α-Conotoxin AuIB through the Inhibition of the GABA BR-Coupled N-Type Calcium Channel. Mar Drugs 2022; 20:md20120750. [PMID: 36547897 PMCID: PMC9781320 DOI: 10.3390/md20120750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 11/30/2022] Open
Abstract
α-conotoxin AuIB is the only one of the 4/6 type α-conotoxins (α-CTxs) that inhibits the γ-aminobutyric acid receptor B (GABABR)-coupled N-type calcium channel (CaV2.2). To improve its inhibitory activity, a series of variants were synthesized and evaluated according to the structure-activity relationships of 4/7 type α-CTxs targeting GABABR-coupled CaV2.2. Surprisingly, only the substitution of Pro7 with Arg results in a 2-3-fold increase in the inhibition of GABABR-coupled CaV2.2 (IC50 is 0.74 nM); substitutions of position 9-12 with basic or hydrophobic amino acid and the addition of hydrophobic amino acid Leu or Ile at the second loop to mimic 4/7 type α-CTxs all failed to improve the inhibitory activity of AuIB against GABABR-coupled CaV2.2. Interestingly, the most potent form of AuIB[P7R] has disulfide bridges of "1-4, 2-3" (ribbon), which differs from the "1-3, 2-4" (globular) in the isoforms of wildtype AuIB. In addition, AuIB[P7R](globular) displays potent analgesic activity in the acetic acid writhing model and the partial sciatic nerve injury (PNL) model. Our study demonstrated that 4/6 type α-CTxs, with the disulfide bridge connectivity "1-4, 2-3," are also potent inhibitors for GABABR-coupled CaV2.2, exhibiting potent analgesic activity.
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Wang S, Bartels P, Zhao C, Yousuf A, Liu Z, Yu S, Bony AR, Ma X, Dai Q, Sun T, Liu N, Yang M, Yu R, Du W, Adams DJ, Dai Q. A 4/8 Subtype α-Conotoxin Vt1.27 Inhibits N-Type Calcium Channels With Potent Anti-Allodynic Effect. Front Pharmacol 2022; 13:881732. [PMID: 35754473 PMCID: PMC9230573 DOI: 10.3389/fphar.2022.881732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/08/2022] [Indexed: 11/22/2022] Open
Abstract
A novel 4/8 subtype α-conotoxin, Vt1.27 (NCCMFHTCPIDYSRFNC-NH2), was identified from Conus vitulinus in the South China Sea by RACE methods. The peptide was synthesized and structurally characterized. Similar to other α-conotoxins that target neuronal nicotinic acetylcholine receptor (nAChR) subtypes, Vt1.27 inhibited the rat α3β2 nAChR subtype (IC50 = 1160 nM) and was inactive at voltage-gated sodium and potassium channels in rat sensory neurons. However, Vt1.27 inhibited high voltage-activated N-type (CaV2.2) calcium channels expressed in HEK293T cells with an IC50 of 398 nM. An alanine scan of the peptide showed that residues Phe5, Pro9, Ile10, and Ser13 contribute significantly to the inhibitory activity of Vt1.27. The molecular dockings indicate that Vt1.27 inhibits the transmembrane region of CaV2.2, which is different from that of ω-conotoxins. Furthermore, Vt1.27 exhibited potent anti-allodynic effect in rat partial sciatic nerve injury (PNL) and chronic constriction injury (CCI) pain models at 10 nmol/kg level with the intramuscular injection. The pain threshold elevation of Vt1.27 groups was higher than that of α-conotoxin Vc1.1 in CCI rat models. These findings expand our knowledge of targets of α-conotoxins and potentially provide a potent, anti-allodynic peptide for the treatment of neuropathic pain.
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Affiliation(s)
- Shuo Wang
- Beijing Institute of Biotechnology, Beijing, China
- Department of Pharmacy, PLA Rocket Force Characteristic Medical Center, Beijing, China
| | - Peter Bartels
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW, Australia
| | - Cong Zhao
- Department of Chemistry, Renmin University of China, Beijing, China
| | - Arsalan Yousuf
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW, Australia
| | - Zhuguo Liu
- Beijing Institute of Biotechnology, Beijing, China
| | - Shuo Yu
- Beijing Institute of Biotechnology, Beijing, China
| | - Anuja R. Bony
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW, Australia
| | - Xiaoli Ma
- Beijing Institute of Biotechnology, Beijing, China
| | - Qin Dai
- Beijing Institute of Biotechnology, Beijing, China
| | - Ting Sun
- Beijing Institute of Biotechnology, Beijing, China
| | - Na Liu
- Beijing Institute of Biotechnology, Beijing, China
| | - Mengke Yang
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Rilei Yu
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Weihong Du
- Department of Chemistry, Renmin University of China, Beijing, China
- *Correspondence: Qiuyun Dai, ; David J. Adams, ; Weihong Du,
| | - David J. Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW, Australia
- *Correspondence: Qiuyun Dai, ; David J. Adams, ; Weihong Du,
| | - Qiuyun Dai
- Beijing Institute of Biotechnology, Beijing, China
- *Correspondence: Qiuyun Dai, ; David J. Adams, ; Weihong Du,
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10
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Therapeutic potential of viral vectors that express venom peptides for neurological diseases. Med Hypotheses 2022. [DOI: 10.1016/j.mehy.2022.110809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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11
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Gajewiak J, Christensen S, Dowell C, Hararah F, Fisher F, Huynh PN, Olivera B, McIntosh JM. Selective Penicillamine Substitution Enables Development of a Potent Analgesic Peptide that Acts through a Non-Opioid-Based Mechanism. J Med Chem 2021; 64:9271-9278. [PMID: 34142837 PMCID: PMC8360267 DOI: 10.1021/acs.jmedchem.1c00512] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Venom-derived compounds are of broad interest in neuropharmacology and drug development. α-Conotoxins are small disulfide-containing peptides from Conus snails that target nicotinic acetylcholine receptors (nAChRs) and are in clinical development for non-opioid-based treatment of intractable pain. Although refined by evolution for interaction with target prey receptors, enhancements of pharmacological properties are needed for use in mammalian systems. Therefore, we synthesized analogues of α-conotoxin RgIA using a combination of selective penicillamine substitutions together with natural and non-natural amino acid replacements. This approach resulted in a peptide with 9000-fold increased potency on the human α9α10 nAChR and improved resistance to disulfide shuffling compared to the native peptide. The lead analogue, RgIA-5474, potently blocked α9α10 nAChRs, but not opioid- or other pain-related targets. In addition, RgIA-5474 effectively reversed chemotherapy-induced neuropathic pain.
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Affiliation(s)
- Joanna Gajewiak
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - Sean Christensen
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - Cheryl Dowell
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - Fuaad Hararah
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - Fernando Fisher
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - Peter N. Huynh
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - Baldomero Olivera
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
| | - J. Michael McIntosh
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840
- George E. Wahlen Department of Veterans Affairs Medical Center, 500 Foothill Dr, Salt Lake City, UT 84148
- Department of Psychiatry, University of Utah, 501 Chipeta Way, Salt Lake City, UT 84108
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12
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Zheng N, Christensen SB, Dowell C, Purushottam L, Skalicky JJ, McIntosh JM, Chou DHC. Discovery of Methylene Thioacetal-Incorporated α-RgIA Analogues as Potent and Stable Antagonists of the Human α9α10 Nicotinic Acetylcholine Receptor for the Treatment of Neuropathic Pain. J Med Chem 2021; 64:9513-9524. [PMID: 34161094 DOI: 10.1021/acs.jmedchem.1c00802] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
α9-Containing nicotinic acetylcholine receptors (nAChRs) are key targets for the treatment of neuropathic pain. α-Conotoxin RgIA4 is a peptide antagonist of human α9α10 nAChRs with high selectivity. However, structural rearrangement reveals a potential liability for clinical applications. We herein report our designer RgIA analogues stabilized by methylene thioacetal as nonopioid analgesic agents. We demonstrate that replacing disulfide loop I [CysI-CysIII] with methylene thioacetal in the RgIA skeleton results in activity loss, whereas substitution of loop II [CysII-CysIV] can be accommodated. The lead molecule, RgIA-5524, exhibits highly selective inhibition of α9α10 nAChRs with an IC50 of 0.9 nM and much reduced degradation in human serum. In vivo studies showed that RgIA-5524 relieves chemotherapy-induced neuropathic pain in wild type but not α9 knockout mouse models, demonstrating that α9-containing nAChRs are necessary for the therapeutic effects. This work highlights the application of methylene thioacetal as a disulfide surrogate in conotoxin-based, disulfide-rich peptide drugs.
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Affiliation(s)
- Nan Zheng
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Sean B Christensen
- School of Biological Science, University of Utah, Salt Lake City, Utah 84112, United States
| | - Cheryl Dowell
- School of Biological Science, University of Utah, Salt Lake City, Utah 84112, United States
| | - Landa Purushottam
- Department of Pediatrics, Division of Endocrinology and Diabetes, Stanford University, Stanford, California 94305, United States
| | - Jack J Skalicky
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - J Michael McIntosh
- School of Biological Science, University of Utah, Salt Lake City, Utah 84112, United States.,George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah 84108, United States.,Department of Psychiatry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Danny Hung-Chieh Chou
- Department of Pediatrics, Division of Endocrinology and Diabetes, Stanford University, Stanford, California 94305, United States
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13
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Bekbossynova A, Zharylgap A, Filchakova O. Venom-Derived Neurotoxins Targeting Nicotinic Acetylcholine Receptors. Molecules 2021; 26:molecules26113373. [PMID: 34204855 PMCID: PMC8199771 DOI: 10.3390/molecules26113373] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 01/02/2023] Open
Abstract
Acetylcholine was the first neurotransmitter described. The receptors targeted by acetylcholine are found within organisms spanning different phyla and position themselves as very attractive targets for predation, as well as for defense. Venoms of snakes within the Elapidae family, as well as those of marine snails within the Conus genus, are particularly rich in proteins and peptides that target nicotinic acetylcholine receptors (nAChRs). Such compounds are invaluable tools for research seeking to understand the structure and function of the cholinergic system. Proteins and peptides of venomous origin targeting nAChR demonstrate high affinity and good selectivity. This review aims at providing an overview of the toxins targeting nAChRs found within venoms of different animals, as well as their activities and the structural determinants important for receptor binding.
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14
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Abstract
The pancreatic peptide hormone insulin, first discovered exactly 100 years ago, is essential for glycemic control and is used as a therapeutic for the treatment of type 1 and, increasingly, type 2 diabetes. With a worsening global diabetes epidemic and its significant health budget imposition, there is a great demand for new analogues possessing improved physical and functional properties. However, the chemical synthesis of insulin's intricate 51-amino acid, two-chain, three-disulfide bond structure, together with the poor physicochemical properties of both the individual chains and the hormone itself, has long represented a major challenge to organic chemists. This review provides a timely overview of the past efforts to chemically assemble this fascinating hormone using an array of strategies to enable both correct folding of the two chains and selective formation of disulfide bonds. These methods not only have contributed to general peptide synthesis chemistry and enabled access to the greatly growing numbers of insulin-like and cystine-rich peptides but also, today, enable the production of insulin at the synthetic efficiency levels of recombinant DNA expression methods. They have led to the production of a myriad of novel analogues with optimized structural and functional features and of the feasibility for their industrial manufacture.
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15
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Zhang B, Ren M, Xiong Y, Li H, Wu Y, Fu Y, Zhangsun D, Dong S, Luo S. Cysteine [2,4] Disulfide Bond as a New Modifiable Site of α-Conotoxin TxIB. Mar Drugs 2021; 19:md19020119. [PMID: 33671487 PMCID: PMC7926623 DOI: 10.3390/md19020119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/03/2021] [Accepted: 02/16/2021] [Indexed: 12/15/2022] Open
Abstract
α-Conotoxin TxIB, a selective antagonist of α6/α3β2β3 nicotinic acetylcholine receptor, could be a potential therapeutic agent for addiction and Parkinson's disease. As a peptide with a complex pharmacophoric conformation, it is important and difficult to find a modifiable site which can be modified effectively and efficiently without activity loss. In this study, three xylene scaffolds were individually reacted with one pair of the cysteine residues ([1,3] or [2,4]), and iodine oxidation was used to form a disulfide bond between the other pair. Overall, six analogs were synthesized with moderate isolated yields from 55% to 65%, which is four times higher than the traditional two-step oxidation with orthogonal protection on cysteines. The cysteine [2,4] modified analogs, with higher stability in human serum than native TxIB, showed obvious inhibitory effect and selectivity on α6/α3β2β3 nicotinic acetylcholine receptors (nAChRs), which was 100 times more than the cysteine [1,3] modified ones. This result demonstrated that the cysteine [2,4] disulfide bond is a new modifiable site of TxIB, and further modification can be a simple and feasible strategy for the exploitation and utilization of α-Conotoxin TxIB in drug discovery.
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Affiliation(s)
- Baojian Zhang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
| | - Maomao Ren
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
| | - Yang Xiong
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
| | - Haonan Li
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
| | - Yong Wu
- Medical School, Guangxi University, Nanning 530004, China;
| | - Ying Fu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
- Medical School, Guangxi University, Nanning 530004, China;
| | - Shuai Dong
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
- Correspondence: (S.D.); (S.L.)
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Laboratory for Marine Drugs of Haikou, School of Life and Pharmaceutical Sciences, Hainan University, Haikou 570228, China; (B.Z.); (M.R.); (Y.X.); (H.L.); (Y.F.); (D.Z.)
- Medical School, Guangxi University, Nanning 530004, China;
- Correspondence: (S.D.); (S.L.)
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16
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Li X, Tae HS, Chu Y, Jiang T, Adams DJ, Yu R. Medicinal chemistry, pharmacology, and therapeutic potential of α-conotoxins antagonizing the α9α10 nicotinic acetylcholine receptor. Pharmacol Ther 2020; 222:107792. [PMID: 33309557 DOI: 10.1016/j.pharmthera.2020.107792] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
α-Conotoxins are disulfide-rich and well-structured peptides, most of which can block nicotinic acetylcholine receptors (nAChRs) with exquisite selectivity and potency. There are various nAChR subtypes, of which the α9α10 nAChR functions as a heteromeric ionotropic receptor in the mammalian cochlea and mediates postsynaptic transmission from the medial olivocochlear. The α9α10 nAChR subtype has also been proposed as a target for the treatment of neuropathic pain and the suppression of breast cancer cell proliferation. Therefore, α-conotoxins targeting the α9α10 nAChR are potentially useful in the development of specific therapeutic drugs and pharmacological tools. Despite dissimilarities in their amino acid sequence and structures, these conopeptides are potent antagonists of the α9α10 nAChR subtype. Consequently, the activity and stability of these peptides have been subjected to chemical modifications. The resulting synthetic analogues have not only functioned as molecular probes to explore ligand binding sites of the α9α10 nAChR, but also have the potential to become candidates for drug development. From the perspectives of medicinal chemistry and pharmacology, we highlight the structure and function of the α9α10 nAChR and review studies of α-conotoxins targeting it, including their three-dimensional structures, structure optimization strategies, and binding modes at the α9α10 nAChR, as well as their therapeutic potential.
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Affiliation(s)
- Xiao Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Yanyan Chu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China; Innovation Platform of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266100, China
| | - Tao Jiang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - David J Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, New South Wales 2522, Australia.
| | - Rilei Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China; Innovation Platform of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266100, China.
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17
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Turner A, Kaas Q, Craik DJ. Hormone-like conopeptides - new tools for pharmaceutical design. RSC Med Chem 2020; 11:1235-1251. [PMID: 34095838 PMCID: PMC8126879 DOI: 10.1039/d0md00173b] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 09/11/2020] [Indexed: 12/24/2022] Open
Abstract
Conopeptides are a diverse family of peptides found in the venoms of marine cone snails and are used in prey capture and host defence. Because of their potent activity on a range of mammalian targets they have attracted interest as leads in drug design. Until recently most focus had been on studying conopeptides having activity at ion channels and related neurological targets but, with recent discoveries that some conopeptides might play hormonal roles, a new area of conopeptide research has opened. In this article we first summarize the canonical pharmaceutical families of Conus venom peptides and then focus on new research relating to hormone-like conopeptides and their potential applications. Finally, we briefly examine methods of chemically stabilizing conopeptides to improve their pharmacological properties. A summary is presented of conopeptides in clinical trials and a call for future work on hormone-like conopeptides.
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Affiliation(s)
- Ashlin Turner
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland Brisbane Queensland 4072 Australia
| | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland Brisbane Queensland 4072 Australia
| | - David J Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland Brisbane Queensland 4072 Australia
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18
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Kennedy AC, Belgi A, Husselbee BW, Spanswick D, Norton RS, Robinson AJ. α-Conotoxin Peptidomimetics: Probing the Minimal Binding Motif for Effective Analgesia. Toxins (Basel) 2020; 12:E505. [PMID: 32781580 PMCID: PMC7472027 DOI: 10.3390/toxins12080505] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/29/2020] [Accepted: 08/03/2020] [Indexed: 12/18/2022] Open
Abstract
Several analgesic α-conotoxins have been isolated from marine cone snails. Structural modification of native peptides has provided potent and selective analogues for two of its known biological targets-nicotinic acetylcholine and γ-aminobutyric acid (GABA) G protein-coupled (GABAB) receptors. Both of these molecular targets are implicated in pain pathways. Despite their small size, an incomplete understanding of the structure-activity relationship of α-conotoxins at each of these targets has hampered the development of therapeutic leads. This review scrutinises the N-terminal domain of the α-conotoxin family of peptides, a region defined by an invariant disulfide bridge, a turn-inducing proline residue and multiple polar sidechain residues, and focusses on structural features that provide analgesia through inhibition of high-voltage-activated Ca2+ channels. Elucidating the bioactive conformation of this region of these peptides may hold the key to discovering potent drugs for the unmet management of debilitating chronic pain associated with a wide range of medical conditions.
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Affiliation(s)
- Adam C. Kennedy
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia; (A.C.K.); (A.B.); (B.W.H.)
| | - Alessia Belgi
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia; (A.C.K.); (A.B.); (B.W.H.)
| | - Benjamin W. Husselbee
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia; (A.C.K.); (A.B.); (B.W.H.)
| | - David Spanswick
- Biomedicine Discovery Institute and the Department of Physiology, Monash University, Victoria 3800, Australia;
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
- NeuroSolutions Ltd., Coventry CV4 7AL, UK
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Science, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia;
- ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria 3052, Australia
| | - Andrea J. Robinson
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia; (A.C.K.); (A.B.); (B.W.H.)
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19
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Tomassi S, Trotta AM, Ieranò C, Merlino F, Messere A, Rea G, Santoro F, Brancaccio D, Carotenuto A, D'Amore VM, Di Leva FS, Novellino E, Cosconati S, Marinelli L, Scala S, Di Maro S. Disulfide Bond Replacement with 1,4‐ and 1,5‐Disubstituted [1,2,3]‐Triazole on C‐X‐C Chemokine Receptor Type 4 (CXCR4) Peptide Ligands: Small Changes that Make Big Differences. Chemistry 2020; 26:10113-10125. [DOI: 10.1002/chem.202002468] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/29/2020] [Indexed: 01/10/2023]
Affiliation(s)
- Stefano Tomassi
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Anna Maria Trotta
- U.O.C. “Bersagli molecolari del microambiente” Istituto Nazionale Tumori—IRCCS—Fondazione “G. Pascale” Via M. Semmola 80131 Naples Italy
| | - Caterina Ieranò
- U.O.C. “Bersagli molecolari del microambiente” Istituto Nazionale Tumori—IRCCS—Fondazione “G. Pascale” Via M. Semmola 80131 Naples Italy
| | - Francesco Merlino
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Anna Messere
- DiSTABiF University of Campania “Luigi Vanvitelli” Via Vivaldi 43 81100 Caserta Italy
| | - Giuseppina Rea
- U.O.C. “Bersagli molecolari del microambiente” Istituto Nazionale Tumori—IRCCS—Fondazione “G. Pascale” Via M. Semmola 80131 Naples Italy
| | - Federica Santoro
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Diego Brancaccio
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Alfonso Carotenuto
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Vincenzo Maria D'Amore
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Francesco Saverio Di Leva
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Ettore Novellino
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Sandro Cosconati
- DiSTABiF University of Campania “Luigi Vanvitelli” Via Vivaldi 43 81100 Caserta Italy
| | - Luciana Marinelli
- Department of Pharmacy University of Naples “Federico II” Via Domenico Montesano 49 80131 Naples Italy
| | - Stefania Scala
- U.O.C. “Bersagli molecolari del microambiente” Istituto Nazionale Tumori—IRCCS—Fondazione “G. Pascale” Via M. Semmola 80131 Naples Italy
| | - Salvatore Di Maro
- DiSTABiF University of Campania “Luigi Vanvitelli” Via Vivaldi 43 81100 Caserta Italy
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20
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Zheng N, Christensen SB, Blakely A, Dowell C, Purushottam L, McIntosh JM, Chou DHC. Development of Conformationally Constrained α-RgIA Analogues as Stable Peptide Antagonists of Human α9α10 Nicotinic Acetylcholine Receptors. J Med Chem 2020; 63:8380-8387. [PMID: 32597184 DOI: 10.1021/acs.jmedchem.0c00613] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Non-opioid therapeutics for the treatment of neuropathic pain are urgently needed to address the ongoing opioid crisis. Peptides from cone snail venoms have served as invaluable molecules to target key pain-related receptors but can suffer from unfavorable physicochemical properties, which limit their therapeutic potential. In this work, we developed conformationally constrained α-RgIA analogues with high potency, receptor selectivity, and enhanced human serum stability to target the human α9α10 nicotinic acetylcholine receptor. The key lactam linkage introduced in α-RgIA fixed the favored globular conformation and suppressed disulfide scrambling. The NMR structure of the macrocyclic peptide overlays well with that of α-RgIA4, demonstrating that the cyclization does not perturb the overall conformation of backbone and key side-chain residues. Finally, a molecular docking model was used to rationalize the selective binding between a macrocyclic analogue and the α9α10 nicotinic acetylcholine receptor. These conformationally constrained antagonists are therefore promising candidates for antinociceptive therapeutic intervention.
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Affiliation(s)
- Nan Zheng
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Sean B Christensen
- School of Biological Science, University of Utah, Salt Lake City, Utah 84112, United States
| | - Alan Blakely
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Cheryl Dowell
- School of Biological Science, University of Utah, Salt Lake City, Utah 84112, United States
| | - Landa Purushottam
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - J Michael McIntosh
- School of Biological Science, University of Utah, Salt Lake City, Utah 84112, United States.,Department of Psychiatry, University of Utah, Salt Lake City, Utah 84112, United States.,George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah 84108, United States
| | - Danny Hung-Chieh Chou
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States.,Department of Pediatrics, Division of Endocrinology and Diabetes, Stanford, California 94305, United States
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21
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Mohan MK, Abraham N, R P R, Jayaseelan BF, Ragnarsson L, Lewis RJ, Sarma SP. Structure and allosteric activity of a single-disulfide conopeptide from Conus zonatus at human α3β4 and α7 nicotinic acetylcholine receptors. J Biol Chem 2020; 295:7096-7112. [PMID: 32234761 DOI: 10.1074/jbc.ra119.012098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/26/2020] [Indexed: 11/06/2022] Open
Abstract
Conopeptides are neurotoxic peptides in the venom of marine cone snails and have broad therapeutic potential for managing pain and other conditions. Here, we identified the single-disulfide peptides Czon1107 and Cca1669 from the venoms of Conus zonatus and Conus caracteristicus, respectively. We observed that Czon1107 strongly inhibits the human α3β4 (IC50 15.7 ± 3.0 μm) and α7 (IC50 77.1 ± 0.05 μm) nicotinic acetylcholine receptor (nAChR) subtypes, but the activity of Cca1669 remains to be identified. Czon1107 acted at a site distinct from the orthosteric receptor site. Solution NMR experiments revealed that Czon1107 exists in equilibrium between conformational states that are the result of a key Ser4-Pro5 cis-trans isomerization. Moreover, we found that the X-Pro amide bonds in the inter-cysteine loop are rigidly constrained to cis conformations. Structure-activity experiments of Czon1107 and its variants at positions P5 and P7 revealed that the conformation around the X-Pro bonds (cis-trans) plays an important role in receptor subtype selectivity. The cis conformation at the Cys6-Pro7 peptide bond was essential for α3β4 nAChR subtype allosteric selectivity. In summary, we have identified a unique single-disulfide conopeptide with a noncompetitive, potentially allosteric inhibitory mechanism at the nAChRs. The small size and rigidity of the Czon1107 peptide could provide a scaffold for rational drug design strategies for allosteric nAChR modulation. This new paradigm in the "conotoxinomic" structure-function space provides an impetus to screen venom from other Conus species for similar, short bioactive peptides that allosterically modulate ligand-gated receptor function.
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Affiliation(s)
- Madhan Kumar Mohan
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Nikita Abraham
- Institute for Molecular Bioscience, Queensland Bioscience Precinct, The University of Queensland, 306 Carmody Rd., St. Lucia Queensland 4072, Australia
| | - Rajesh R P
- Sathyabama Institute of Science and Technology, Jeppiaar Nagar, Rajiv Gandhi Salai, Chennai 600119, Tamil Nadu, India
| | | | - Lotten Ragnarsson
- Institute for Molecular Bioscience, Queensland Bioscience Precinct, The University of Queensland, 306 Carmody Rd., St. Lucia Queensland 4072, Australia
| | - Richard J Lewis
- Institute for Molecular Bioscience, Queensland Bioscience Precinct, The University of Queensland, 306 Carmody Rd., St. Lucia Queensland 4072, Australia
| | - Siddhartha P Sarma
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka 560012, India
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22
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Mansbach RA, Chakraborty S, Travers T, Gnanakaran S. Graph-Directed Approach for Downselecting Toxins for Experimental Structure Determination. Mar Drugs 2020; 18:E256. [PMID: 32422972 PMCID: PMC7281422 DOI: 10.3390/md18050256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/24/2020] [Accepted: 05/09/2020] [Indexed: 11/29/2022] Open
Abstract
Conotoxins are short, cysteine-rich peptides of great interest as novel therapeutic leads and of great concern as lethal biological agents due to their high affinity and specificity for various receptors involved in neuromuscular transmission. Currently, of the approximately 6000 known conotoxin sequences, only about 3% have associated structural characterization, which leads to a bottleneck in rapid high-throughput screening (HTS) for identification of potential leads or threats. In this work, we combine a graph-based approach with homology modeling to expand the library of conotoxin structures and to identify those conotoxin sequences that are of the greatest value for experimental structural characterization. The latter would allow for the rapid expansion of the known structural space for generating high quality template-based models. Our approach generalizes to other evolutionarily-related, short, cysteine-rich venoms of interest. Overall, we present and validate an approach for venom structure modeling and experimental guidance and employ it to produce a 290%-larger library of approximate conotoxin structures for HTS. We also provide a set of ranked conotoxin sequences for experimental structure determination to further expand this library.
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Affiliation(s)
- Rachael A. Mansbach
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (R.A.M.); (S.C.); (T.T.)
| | - Srirupa Chakraborty
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (R.A.M.); (S.C.); (T.T.)
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Timothy Travers
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (R.A.M.); (S.C.); (T.T.)
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - S. Gnanakaran
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (R.A.M.); (S.C.); (T.T.)
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Wiedemann C, Kumar A, Lang A, Ohlenschläger O. Cysteines and Disulfide Bonds as Structure-Forming Units: Insights From Different Domains of Life and the Potential for Characterization by NMR. Front Chem 2020; 8:280. [PMID: 32391319 PMCID: PMC7191308 DOI: 10.3389/fchem.2020.00280] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 03/23/2020] [Indexed: 12/22/2022] Open
Abstract
Disulfide bridges establish a fundamental element in the molecular architecture of proteins and peptides which are involved e.g., in basic biological processes or acting as toxins. NMR spectroscopy is one method to characterize the structure of bioactive compounds including cystine-containing molecules. Although the disulfide bridge itself is invisible in NMR, constraints obtained via the neighboring NMR-active nuclei allow to define the underlying conformation and thereby to resolve their functional background. In this mini-review we present shortly the impact of cysteine and disulfide bonds in the proteasome from different domains of life and give a condensed overview of recent NMR applications for the characterization of disulfide-bond containing biomolecules including advantages and limitations of the different approaches.
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Affiliation(s)
- Christoph Wiedemann
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Amit Kumar
- Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany
| | - Andras Lang
- Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany
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24
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Structure and Activity Studies of Disulfide-Deficient Analogues of αO-Conotoxin GeXIVA. J Med Chem 2020; 63:1564-1575. [DOI: 10.1021/acs.jmedchem.9b01409] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Jin AH, Muttenthaler M, Dutertre S, Himaya SWA, Kaas Q, Craik DJ, Lewis RJ, Alewood PF. Conotoxins: Chemistry and Biology. Chem Rev 2019; 119:11510-11549. [PMID: 31633928 DOI: 10.1021/acs.chemrev.9b00207] [Citation(s) in RCA: 168] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The venom of the marine predatory cone snails (genus Conus) has evolved for prey capture and defense, providing the basis for survival and rapid diversification of the now estimated 750+ species. A typical Conus venom contains hundreds to thousands of bioactive peptides known as conotoxins. These mostly disulfide-rich and well-structured peptides act on a wide range of targets such as ion channels, G protein-coupled receptors, transporters, and enzymes. Conotoxins are of interest to neuroscientists as well as drug developers due to their exquisite potency and selectivity, not just against prey but also mammalian targets, thereby providing a rich source of molecular probes and therapeutic leads. The rise of integrated venomics has accelerated conotoxin discovery with now well over 10,000 conotoxin sequences published. However, their structural and pharmacological characterization lags considerably behind. In this review, we highlight the diversity of new conotoxins uncovered since 2014, their three-dimensional structures and folds, novel chemical approaches to their syntheses, and their value as pharmacological tools to unravel complex biology. Additionally, we discuss challenges and future directions for the field.
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Affiliation(s)
- Ai-Hua Jin
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Markus Muttenthaler
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia.,Institute of Biological Chemistry, Faculty of Chemistry , University of Vienna , 1090 Vienna , Austria
| | - Sebastien Dutertre
- Département des Acides Amines, Peptides et Protéines, Unité Mixte de Recherche 5247, Université Montpellier 2-Centre Nationale de la Recherche Scientifique , Institut des Biomolécules Max Mousseron , Place Eugène Bataillon , 34095 Montpellier Cedex 5 , France
| | - S W A Himaya
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Quentin Kaas
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - David J Craik
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Richard J Lewis
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Paul F Alewood
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
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26
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Mansbach RA, Travers T, McMahon BH, Fair JM, Gnanakaran S. Snails In Silico: A Review of Computational Studies on the Conopeptides. Mar Drugs 2019; 17:E145. [PMID: 30832207 PMCID: PMC6471681 DOI: 10.3390/md17030145] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/21/2019] [Accepted: 02/22/2019] [Indexed: 12/26/2022] Open
Abstract
Marine cone snails are carnivorous gastropods that use peptide toxins called conopeptides both as a defense mechanism and as a means to immobilize and kill their prey. These peptide toxins exhibit a large chemical diversity that enables exquisite specificity and potency for target receptor proteins. This diversity arises in terms of variations both in amino acid sequence and length, and in posttranslational modifications, particularly the formation of multiple disulfide linkages. Most of the functionally characterized conopeptides target ion channels of animal nervous systems, which has led to research on their therapeutic applications. Many facets of the underlying molecular mechanisms responsible for the specificity and virulence of conopeptides, however, remain poorly understood. In this review, we will explore the chemical diversity of conopeptides from a computational perspective. First, we discuss current approaches used for classifying conopeptides. Next, we review different computational strategies that have been applied to understanding and predicting their structure and function, from machine learning techniques for predictive classification to docking studies and molecular dynamics simulations for molecular-level understanding. We then review recent novel computational approaches for rapid high-throughput screening and chemical design of conopeptides for particular applications. We close with an assessment of the state of the field, emphasizing important questions for future lines of inquiry.
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Affiliation(s)
- Rachael A Mansbach
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Timothy Travers
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Benjamin H McMahon
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Jeanne M Fair
- Biosecurity and Public Health Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - S Gnanakaran
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
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27
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Ren J, Zhu X, Xu P, Li R, Fu Y, Dong S, Zhangsun D, Wu Y, Luo S. d-Amino Acid Substitution of α-Conotoxin RgIA Identifies its Critical Residues and Improves the Enzymatic Stability. Mar Drugs 2019; 17:md17030142. [PMID: 30823399 PMCID: PMC6472032 DOI: 10.3390/md17030142] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 02/17/2019] [Accepted: 02/22/2019] [Indexed: 12/22/2022] Open
Abstract
α-Conotoxin RgIA is a selective and potent competitive antagonist of rat α9α10 nicotinic acetylcholine receptors (nAChR), but it is much less potent towards human α9α10 nAChR. Furthermore, RgIA is susceptible to proteolytic degradation due to containing four arginine residues. These disadvantages greatly limit its use for clinical applications. The purpose of this research was to identify critical stereocenters of RgIA and discover more stable analogues, enhancing its bioavailability by using the d-amino acid scan method. The activity of each variant was investigated against rat and human α9α10 nAChRs, which were expressed in Xenopus oocytes. Experimental assays showed that 14 out of 15 analogues had a substantial reduction in potency towards rat α9α10 nAChR. Noticeably, analogue 13 retained full biological activity compared with RgIA. Meanwhile, two other analogues, 14 and 15, of which l-Args were substituted with d-Args, exhibited a significantly increased potency towards human α9α10 nAChR, although these analogues showed decreased activities against rat α9α10 nAChR. Additionally, these three analogues exhibited a high resistance against enzymatic degradation in human serum and simulated intestinal fluid (SIF). Collectively, our findings suggest that a d-amino acid scan is a useful strategy for investigating how the side-chain chirality of amino acids affects the structure and function of peptides and may facilitate the development of more stable analogues to increase therapeutic potential.
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Affiliation(s)
- Jie Ren
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Xiaopeng Zhu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Pan Xu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Rui Li
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Ying Fu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Shuai Dong
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Yong Wu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
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28
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Affiliation(s)
- Bo Yang
- Department of Chemistry, Inorganometallic Catalyst Design Center, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Donald G. Truhlar
- Department of Chemistry, Inorganometallic Catalyst Design Center, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
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29
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Cai F, Xu N, Liu Z, Ding R, Yu S, Dong M, Wang S, Shen J, Tae HS, Adams DJ, Zhang X, Dai Q. Targeting of N-Type Calcium Channels via GABAB-Receptor Activation by α-Conotoxin Vc1.1 Variants Displaying Improved Analgesic Activity. J Med Chem 2018; 61:10198-10205. [DOI: 10.1021/acs.jmedchem.8b01343] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Fengtao Cai
- Beijing Institute of Biotechnology, Beijing 100071, China
- School of Preclinical Medicine, Guangxi Medical University, Nanning 530021, China
| | - Ning Xu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Zhuguo Liu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Rong Ding
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Shuo Yu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Mingxin Dong
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Shuo Wang
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Jintao Shen
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
| | - David J. Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
| | - Xuerong Zhang
- School of Preclinical Medicine, Guangxi Medical University, Nanning 530021, China
| | - Qiuyun Dai
- Beijing Institute of Biotechnology, Beijing 100071, China
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30
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Wu X, Tae HS, Huang YH, Adams DJ, Craik DJ, Kaas Q. Stoichiometry dependent inhibition of rat α3β4 nicotinic acetylcholine receptor by the ribbon isomer of α-conotoxin AuIB. Biochem Pharmacol 2018; 155:288-297. [PMID: 30009767 DOI: 10.1016/j.bcp.2018.07.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 07/11/2018] [Indexed: 11/17/2022]
Abstract
The ribbon isomer of α-conotoxin AuIB has 10-fold greater potency than the wild-type globular isomer at inhibiting nicotinic acetylcholine receptors (nAChRs) in rat parasympathetic neurons, and unlike its globular isoform, ribbon AuIB only targets a specific stoichiometry of the α3β4 nAChR subtype. Previous electrophysiological recordings of AuIB indicated that ribbon AuIB binds to the α3(+)α3(-) interface within the nAChR extracellular domain, which is displayed by the (α3)3(β4)2 stoichiometry but not by (α3)2(β4)3. This specificity for a particular stoichiometry is remarkable and suggests that ribbon isoforms of α-conotoxins might have great potential in drug design. In this study, we investigated the binding mode and structure-activity relationships of ribbon AuIB using a combination of molecular modeling and electrophysiology recording to determine the features that underpin its selectivity. An alanine scan showed that positions 4 and 9 of ribbon AuIB are the main determinants of the interaction with (α3)3(β4)2 nAChR. Our computational models indicate that the first loop of ribbon AuIB binds in the "aromatic box" of the acetylcholine orthosteric binding site, similar to that of globular AuIB. In contrast, the second loop and the termini of the ribbon isomer have different orientations and interactions in the binding sites to those of the globular isomer. The structure-activity relationships reported herein should be useful to design peptides displaying a ribbon α-conotoxin scaffold for inhibition of nAChR subtypes that have hitherto been difficult to selectively target.
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Affiliation(s)
- Xiaosa Wu
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), The University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Yen-Hua Huang
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David J Adams
- Illawarra Health and Medical Research Institute (IHMRI), The University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - David J Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
| | - Quentin Kaas
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
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31
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Fang GM, Chen XX, Yang QQ, Zhu LJ, Li NN, Yu HZ, Meng XM. Discovery, structure, and chemical synthesis of disulfide-rich peptide toxins and their analogs. CHINESE CHEM LETT 2018. [DOI: 10.1016/j.cclet.2018.02.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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32
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Affiliation(s)
- Varsha J. Thombare
- School of ChemistryThe University of MelbourneVictoria3010 Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of MelbourneVictoria3010 Australia
| | - Craig A. Hutton
- School of ChemistryThe University of MelbourneVictoria3010 Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of MelbourneVictoria3010 Australia
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33
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Yu S, Wu Y, Xu P, Wang S, Zhangsun D, Luo S. Effects of serum, enzyme, thiol, and forced degradation on the stabilities of αO-Conotoxin GeXIVA[1,2] and GeXIVA [1,4]. Chem Biol Drug Des 2018; 91:1030-1041. [DOI: 10.1111/cbdd.13167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/22/2017] [Accepted: 12/17/2017] [Indexed: 01/07/2023]
Affiliation(s)
- Shurun Yu
- Key Laboratory of Tropical Biological Resources, Ministry of Education; Hainan University; Haikou China
- Key Laboratory for Marine Drugs of Haikou; Hainan University; Haikou China
- Institute of Tropical Agriculture and Forestry; Hainan University; Haikou China
| | - Yong Wu
- Key Laboratory of Tropical Biological Resources, Ministry of Education; Hainan University; Haikou China
- Key Laboratory for Marine Drugs of Haikou; Hainan University; Haikou China
| | - Pan Xu
- Key Laboratory of Tropical Biological Resources, Ministry of Education; Hainan University; Haikou China
- Key Laboratory for Marine Drugs of Haikou; Hainan University; Haikou China
- Institute of Tropical Agriculture and Forestry; Hainan University; Haikou China
| | - Shuai Wang
- Key Laboratory of Tropical Biological Resources, Ministry of Education; Hainan University; Haikou China
- Key Laboratory for Marine Drugs of Haikou; Hainan University; Haikou China
- Institute of Tropical Agriculture and Forestry; Hainan University; Haikou China
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources, Ministry of Education; Hainan University; Haikou China
- Key Laboratory for Marine Drugs of Haikou; Hainan University; Haikou China
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources, Ministry of Education; Hainan University; Haikou China
- Key Laboratory for Marine Drugs of Haikou; Hainan University; Haikou China
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34
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α-Conotoxins to explore the molecular, physiological and pathophysiological functions of neuronal nicotinic acetylcholine receptors. Neurosci Lett 2017; 679:24-34. [PMID: 29199094 DOI: 10.1016/j.neulet.2017.11.063] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 12/22/2022]
Abstract
The vast diversity of neuronal nicotinic acetylcholine subunits expressed in the central and peripheral nervous systems, as well as in non-neuronal tissues, constitutes a formidable challenge for researchers and clinicians to decipher the role of particular subtypes, including complex subunit associations, in physiological and pathophysiological functions. Many natural products target the nAChRs, but there is no richer source of nicotinic ligands than the venom of predatory gastropods known as cone snails. Indeed, every single species of cone snail was shown to produce at least one type of such α-conotoxins. These tiny peptides (10-25 amino acids), constrained by disulfide bridges, proved to be unvaluable tools to investigate the structure and function of nAChRs, some of them having also therapeutic potential. In this review, we provide a recent update on the pharmacology and subtype specificity of several major α-conotoxins.
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35
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G-Protein Coupled Receptors Targeted by Analgesic Venom Peptides. Toxins (Basel) 2017; 9:toxins9110372. [PMID: 29144441 PMCID: PMC5705987 DOI: 10.3390/toxins9110372] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 12/14/2022] Open
Abstract
Chronic pain is a complex and debilitating condition associated with a large personal and socioeconomic burden. Current pharmacological approaches to treating chronic pain such as opioids, antidepressants and anticonvulsants exhibit limited efficacy in many patients and are associated with dose-limiting side effects that hinder their clinical use. Therefore, improved strategies for the pharmacological treatment of pathological pain are urgently needed. G-protein coupled receptors (GPCRs) are ubiquitously expressed on the surface of cells and act to transduce extracellular signals and regulate physiological processes. In the context of pain, numerous and diverse families of GPCRs expressed in pain pathways regulate most aspects of physiological and pathological pain and are thus implicated as potential targets for therapy of chronic pain. In the search for novel compounds that produce analgesia via GPCR modulation, animal venoms offer an enormous and virtually untapped source of potent and selective peptide molecules. While many venom peptides target voltage-gated and ligand-gated ion channels to inhibit neuronal excitability and blunt synaptic transmission of pain signals, only a small proportion are known to interact with GPCRs. Of these, only a few have shown analgesic potential in vivo. Here we review the current state of knowledge regarding venom peptides that target GPCRs to produce analgesia, and their development as therapeutic compounds.
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36
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Engel J, Smit W, Foscato M, Occhipinti G, Törnroos KW, Jensen VR. Loss and Reformation of Ruthenium Alkylidene: Connecting Olefin Metathesis, Catalyst Deactivation, Regeneration, and Isomerization. J Am Chem Soc 2017; 139:16609-16619. [DOI: 10.1021/jacs.7b07694] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Julien Engel
- Institute
of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Wietse Smit
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Marco Foscato
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Giovanni Occhipinti
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Karl W. Törnroos
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Vidar R. Jensen
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
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37
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Gori A, Gagni P, Rinaldi S. Disulfide Bond Mimetics: Strategies and Challenges. Chemistry 2017; 23:14987-14995. [PMID: 28749012 DOI: 10.1002/chem.201703199] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Indexed: 12/25/2022]
Abstract
The activity profile of many biologically relevant proteins and peptides often relies on a precise 3D structural organization. In this context, disulfide bonds are natural covalent constraints that play a key role in driving and stabilizing the folding pattern of these molecules. Despite its prominent significance as structural motif, the disulfide bond itself is inherently unstable under physiological conditions, posing a major limit to the use and development of disulfide-rich peptides and proteins as molecular tools and drug lead compounds. To tackle this restriction, disulfide engineering with stable functional analogues has arisen a considerable interest. Here, the most popular approaches to disulfide replacement are reviewed and discussed with particular emphasis on advantages and limitations under both functional and synthetic perspectives.
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Affiliation(s)
- Alessandro Gori
- Istituto di Chimica del Riconoscimento Molecolare (ICRM), National Research Council of, Italy) (CNR, via Mario Bianco 9, 20131, Milano, Italy
| | - Paola Gagni
- Istituto di Chimica del Riconoscimento Molecolare (ICRM), National Research Council of, Italy) (CNR, via Mario Bianco 9, 20131, Milano, Italy
| | - Silvia Rinaldi
- Istituto di Chimica del Riconoscimento Molecolare (ICRM), National Research Council of, Italy) (CNR, via Mario Bianco 9, 20131, Milano, Italy
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38
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Occhipinti G, Törnroos KW, Jensen VR. Pyridine-Stabilized Fast-Initiating Ruthenium Monothiolate Catalysts for Z-Selective Olefin Metathesis. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00441] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Giovanni Occhipinti
- Department of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Karl W. Törnroos
- Department of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Vidar R. Jensen
- Department of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
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39
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Hone AJ, Servent D, McIntosh JM. α9-containing nicotinic acetylcholine receptors and the modulation of pain. Br J Pharmacol 2017; 175:1915-1927. [PMID: 28662295 DOI: 10.1111/bph.13931] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 06/09/2017] [Accepted: 06/13/2017] [Indexed: 01/01/2023] Open
Abstract
Neuropathic pain is a complex and debilitating syndrome for which there are few effective pharmacological treatments. Opioid-based medications are initially effective for acute pain, but tolerance to their analgesic effects quickly develops, and long-term use often leads to physical dependence and addiction. Furthermore, neuropathic pain is generally resistant to non-steroidal anti-inflammatory drugs. Other classes of medications including antidepressants, antiepileptics and voltage-gated calcium channel inhibitors are only partially effective in most patients, may be associated with significant side effects and have few disease-modifying effects on the underlying pathology. Medications that act through new mechanisms of action, and particularly ones that have disease-modifying properties, would be highly desirable. In the last decade, a potential new target for the treatment of neuropathic pain has emerged: the α9-containing nicotinic acetylcholine receptor (nAChR). Recent studies indicate that antagonists of α9-containing nAChRs are analgesic in animal models of neuropathic pain. These nerve injury models include chronic constriction injury, partial sciatic nerve ligation, streptozotocin-induced diabetic neuropathy and chemotherapeutic-induced neuropathy. This review details the history and state of the field regarding the role that α9-containing nAChRs may play in neuropathic pain. An alternative hypothesis that α-conotoxins exert their therapeutic effect through blocking N-type calcium channels via activation of GABAB receptors is also reviewed. Understanding how antagonists of α9-containing nAChRs exert their therapeutic effects may ultimately result in the development of medications that not only treat but also prevent the development of neuropathic pain states. LINKED ARTICLES This article is part of a themed section on Nicotinic Acetylcholine Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.11/issuetoc.
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Affiliation(s)
- Arik J Hone
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - Denis Servent
- Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), IBITECS, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - J Michael McIntosh
- Department of Biology, University of Utah, Salt Lake City, UT, USA.,George E. Whalen Veterans Affairs Medical Center, Salt Lake City, UT, USA.,Department of Psychiatry, University of Utah, Salt Lake City, UT, USA
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Sadeghi M, McArthur JR, Finol-Urdaneta RK, Adams DJ. Analgesic conopeptides targeting G protein-coupled receptors reduce excitability of sensory neurons. Neuropharmacology 2017; 127:116-123. [PMID: 28533165 DOI: 10.1016/j.neuropharm.2017.05.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/16/2017] [Accepted: 05/18/2017] [Indexed: 01/28/2023]
Abstract
Conotoxins (conopeptides) are a diverse group of peptides isolated from the venom of marine cone snails. Conus peptides modulate pain by interacting with voltage-gated ion channels and G protein-coupled receptors (GPCRs). Opiate drugs targeting GPCRs have long been used, nonetheless, many undesirable side effects associated with opiates have been observed including addiction. Consequently, alternative avenues to pain management are a largely unmet need. It has been shown that various voltage-gated calcium channels (VGCCs) respond to GPCR modulation. Thus, regulation of VGCCs by GPCRs has become a valuable alternative in the management of pain. In this review, we focus on analgesic conotoxins that exert their effects via GPCR-mediated inhibition of ion channels involved in nociception and pain transmission. Specifically, α-conotoxin Vc1.1 activation of GABAB receptors and inhibition of voltage-gated calcium channels as a novel mechanism for reducing the excitability of dorsal root ganglion neurons is described. Vc1.1 and other α-conotoxins have been shown to be analgesic in different animal models of chronic pain. This review will outline the functional effects of conopeptide modulation of GPCRs and how their signalling is translated to downstream components of the pain pathways. Where available we present the proposed signalling mechanisms that couples metabotropic receptor activation to their downstream effectors to produce analgesia. This article is part of the Special Issue entitled 'Venom-derived Peptides as Pharmacological Tools.'
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Affiliation(s)
- Mahsa Sadeghi
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, 2522, Australia
| | - Jeffrey R McArthur
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, 2522, Australia
| | - Rocio K Finol-Urdaneta
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, 2522, Australia
| | - David J Adams
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, 2522, Australia.
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Molecular Engineering of Conus Peptides as Therapeutic Leads. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1030:229-254. [DOI: 10.1007/978-3-319-66095-0_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Gleeson EC, Wang ZJ, Robinson SD, Chhabra S, MacRaild CA, Jackson WR, Norton RS, Robinson AJ. Stereoselective synthesis and structural elucidation of dicarba peptides. Chem Commun (Camb) 2016; 52:4446-9. [PMID: 26892179 DOI: 10.1039/c5cc10540d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile stereoselective synthesis of cis and trans unsaturated dicarba peptides has been established using preformed diaminosuberic acid derivatives as bridging units. In addition, characteristic spectral differences in the (13)C-NMR spectra of the cis- and trans-isomers show that the chemical shift of carbons in the Δ4,5-diaminosuberic acid residue can be used to assign stereochemistry in unsaturated dicarba peptides formed from ring closing metathesis of linear peptide sequences.
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Affiliation(s)
- Ellen C Gleeson
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia.
| | - Zhen J Wang
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia.
| | - Samuel D Robinson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Sandeep Chhabra
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Christopher A MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - W Roy Jackson
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia.
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Andrea J Robinson
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia.
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Abstract
Unusual amino acids are fundamental building blocks of modern medicinal chemistry. The combination of readily functionalized amine and carboxyl groups attached to a chiral central core along with one or two potentially diverse side chains provides a unique three-dimensional structure with a high degree of functionality. This makes them invaluable as starting materials for syntheses of complex molecules, highly diverse elements for SAR campaigns, integral components of peptidomimetic drugs, and potential drugs on their own. This Perspective highlights the diversity of unnatural amino acid structures found in hit-to-lead and lead optimization campaigns and clinical stage and approved drugs, reflecting their increasingly important role in medicinal chemistry.
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Affiliation(s)
- Mark A T Blaskovich
- Institute for Molecular Bioscience, The University of Queensland , Brisbane, Queensland Australia 4072
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Suresh A, Hung A. Molecular simulation study of the unbinding of α-conotoxin [ϒ4E]GID at the α7 and α4β2 neuronal nicotinic acetylcholine receptors. J Mol Graph Model 2016; 70:109-121. [PMID: 27721068 DOI: 10.1016/j.jmgm.2016.09.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 08/11/2016] [Accepted: 09/05/2016] [Indexed: 12/27/2022]
Abstract
The α7 and α4β2 neuronal nicotinic receptors belonging to the family of ligand-gated ion channels are most prevalent in the brain, and are implicated in various neurodegenerative disorders. α-conotoxin GID (and its analogue [ϒ4E]GID) specifically inhibits these subtypes, with more affinity towards the human α7 (hα7) subtype, and is valuable in understanding the physiological roles of these receptors. In this study, we use umbrella-sampling molecular dynamics simulations to understand the mechanism of interaction between [ϒ4E]GID and the agonist binding pockets of the α4β2 and the hα7 receptors, and to estimate their relative binding affinities (ΔGbind). The obtained ΔGbind values indicate stronger interaction with the hα7 receptor, in agreement with previous experimental studies. Simulations also revealed different unbinding pathways between the two receptor subtypes, enabling identification of a number of interactions at locations far from the orthosteric binding site which may explain the difference in [ϒ4E]GID potency. The pathways identified will help in the design of novel conotoxins with increased potency at α4β2, for which there is currently no known highly potent conotoxin inhibitor. Computational mutational free energy analyses also revealed a number of possible single-site mutations to GID which might enhance its selective binding to α4β2 over α7.
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Affiliation(s)
- Abishek Suresh
- School of Science, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
| | - Andrew Hung
- School of Science, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
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Amso Z, Kowalczyk R, Watson M, Park YE, Callon KE, Musson DS, Cornish J, Brimble MA. Structure activity relationship study on the peptide hormone preptin, a novel bone-anabolic agent for the treatment of osteoporosis. Org Biomol Chem 2016; 14:9225-9238. [PMID: 27488745 DOI: 10.1039/c6ob01455k] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Preptin is a 34-residue pancreatic hormone shown to be anabolic to bone in vitro and in vivo. The bone activity of preptin resides within the (1-16) N-terminal fragment. Due to its peptidic nature, the truncated fragment of preptin is enzymatically unstable; however it provides an attractive framework for the creation of stable analogues using various peptidomimetic techniques. An alanine scan of preptin (1-16) was undertaken which showed that substitution of Ser at position 3 or Pro at position 14 did not inhibit the proliferative activity of preptin in primary rat osteoblasts (bone-forming cells). Importantly, Ser-3 to Ala substitution also showed a significant activity on osteoblast differentiation in vitro and increased the formation of mineralised bone matrix. Additional modifications with non-proteinogenic amino acids at position 3 improved the stability in liver microsomes, but diminished the osteoblast proliferative activity. In addition, to provide greater structural diversity, a series of macrocyclic preptin (1-16) analogues was synthesised using head-to-tail and head-to-side chain macrolactamisation as well as ring-closing metathesis. However, a detrimental effect on osteoblast activity was observed upon macrocyclisation.
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Affiliation(s)
- Zaid Amso
- School of Chemical Sciences, The University of Auckland, 23 Symonds St, Auckland 1142, New Zealand.
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Amso Z, Kowalczyk R, Park YE, Watson M, Lin JM, Musson DS, Cornish J, Brimble MA. Synthesis and in vitro bone cell activity of analogues of the cyclohexapeptide dianthin G. Org Biomol Chem 2016; 14:6231-43. [PMID: 27264279 DOI: 10.1039/c6ob00983b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The cyclohexapeptide natural product dianthin G promotes osteoblast (bone-forming cell) proliferation in vitro at nanomolar concentrations, and is therefore considered a promising candidate for the treatment of osteoporosis. An N(α)-methyl amide bond scan of dianthin G was performed to probe the effect of modifying amide bonds on osteoblast proliferation. In addition, to provide greater structural diversity, a series of dicarba dianthin G analogues was synthesised using ring closing metathesis. Dianthin G and one novel dicarba analogue increased the number of human osteoblasts and importantly they did not increase osteoclast (bone-resorbing cell) differentiation in bone marrow cells.
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Affiliation(s)
- Zaid Amso
- School of Chemical Sciences, The University of Auckland, 23 Symonds St, Auckland 1142, New Zealand.
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Smit W, Koudriavtsev V, Occhipinti G, Törnroos KW, Jensen VR. Phosphine-Based Z-Selective Ruthenium Olefin Metathesis Catalysts. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00214] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wietse Smit
- Department of Chemistry, University of Bergen, Allégaten
41, N-5007 Bergen, Norway
| | - Vitali Koudriavtsev
- Department of Chemistry, University of Bergen, Allégaten
41, N-5007 Bergen, Norway
| | - Giovanni Occhipinti
- Department of Chemistry, University of Bergen, Allégaten
41, N-5007 Bergen, Norway
| | - Karl W. Törnroos
- Department of Chemistry, University of Bergen, Allégaten
41, N-5007 Bergen, Norway
| | - Vidar R. Jensen
- Department of Chemistry, University of Bergen, Allégaten
41, N-5007 Bergen, Norway
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Abstract
This review covers the literature published in 2014 for marine natural products (MNPs), with 1116 citations (753 for the period January to December 2014) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1378 in 456 papers for 2014), together with the relevant biological activities, source organisms and country of origin. Reviews, 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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