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Wei W, Xu Q, Wu L, Gong G, Tian Y, Huang H, Li Z. Drug development and potential targets for Cushing's syndrome. Eur J Med Chem 2024; 270:116333. [PMID: 38569434 DOI: 10.1016/j.ejmech.2024.116333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/11/2024] [Accepted: 03/13/2024] [Indexed: 04/05/2024]
Abstract
Cushing's syndrome (CS) is a complex disorder characterized by the excessive secretion of cortisol, with Cushing's disease (CD), particularly associated with pituitary tumors, exhibiting heightened morbidity and mortality. Although transsphenoidal pituitary surgery (TSS) stands as the primary treatment for CD, there is a crucial need to optimize patient prognosis. Current medical therapy serves as an adjunctive measure due to its unsatisfactory efficacy and unpredictable side effects. In this comprehensive review, we delve into recent advances in understanding the pathogenesis of CS and explore therapeutic options by conducting a critical analysis of potential drug targets and candidates. Additionally, we provide an overview of the design strategy employed in previously reported candidates, along with a summary of structure-activity relationship (SAR) analyses and their biological efficacy. This review aims to contribute valuable insights to the evolving landscape of CS research, shedding light on potential avenues for therapeutic development.
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Affiliation(s)
- Wei Wei
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Qianqian Xu
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Liuyi Wu
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Guangyue Gong
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Yucheng Tian
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Huidan Huang
- Center of Drug Screening & Evaluation, Wannan Medical College, Wuhu, Anhui, 241000, PR China.
| | - Zhiyu Li
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, PR China.
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2
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Zhao W, Han S, Qiu N, Feng W, Lu M, Zhang W, Wang M, Zhou Q, Chen S, Xu W, Du J, Chu X, Yi C, Dai A, Hu L, Shen MY, Sun Y, Zhang Q, Ma Y, Zhong W, Yang D, Wang MW, Wu B, Zhao Q. Structural insights into ligand recognition and selectivity of somatostatin receptors. Cell Res 2022; 32:761-772. [PMID: 35739238 PMCID: PMC9343605 DOI: 10.1038/s41422-022-00679-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 05/25/2022] [Indexed: 12/12/2022] Open
Abstract
Somatostatin receptors (SSTRs) play versatile roles in inhibiting the secretion of multiple hormones such as growth hormone and thyroid-stimulating hormone, and thus are considered as targets for treating multiple tumors. Despite great progress made in therapeutic development against this diverse receptor family, drugs that target SSTRs still show limited efficacy with preferential binding affinity and conspicuous side-effects. Here, we report five structures of SSTR2 and SSTR4 in different states, including two crystal structures of SSTR2 in complex with a selective peptide antagonist and a non-peptide agonist, respectively, a cryo-electron microscopy (cryo-EM) structure of Gi1-bound SSTR2 in the presence of the endogenous ligand SST-14, as well as two cryo-EM structures of Gi1-bound SSTR4 in complex with SST-14 and a small-molecule agonist J-2156, respectively. By comparison of the SSTR structures in different states, molecular mechanisms of agonism and antagonism were illustrated. Together with computational and functional analyses, the key determinants responsible for ligand recognition and selectivity of different SSTR subtypes and multiform binding modes of peptide and non-peptide ligands were identified. Insights gained in this study will help uncover ligand selectivity of various SSTRs and accelerate the development of new molecules with better efficacy by targeting SSTRs.
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Affiliation(s)
- Wenli Zhao
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Shuo Han
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, Zhejiang, China
| | - Na Qiu
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wenbo Feng
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Mengjie Lu
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wenru Zhang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
| | - Mu Wang
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Qingtong Zhou
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Shutian Chen
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wei Xu
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Juan Du
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, Zhejiang, China
| | - Xiaojing Chu
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Cuiying Yi
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Antao Dai
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | | | | | | | | | - Yingli Ma
- Amgen Asia R&D Center, Shanghai, China
| | - Wenge Zhong
- Amgen Asia R&D Center, Shanghai, China.,Regor Therapeutics, Shanghai, China
| | - Dehua Yang
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China. .,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
| | - Ming-Wei Wang
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China. .,Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, China. .,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
| | - Beili Wu
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China. .,School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, Zhejiang, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.
| | - Qiang Zhao
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China. .,School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China. .,Zhongshan Institute of Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zhongshan, Guangdong, China.
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3
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Vu O, Bender BJ, Pankewitz L, Huster D, Beck-Sickinger AG, Meiler J. The Structural Basis of Peptide Binding at Class A G Protein-Coupled Receptors. Molecules 2021; 27:molecules27010210. [PMID: 35011444 PMCID: PMC8746363 DOI: 10.3390/molecules27010210] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 12/15/2021] [Accepted: 12/18/2021] [Indexed: 11/16/2022] Open
Abstract
G protein-coupled receptors (GPCRs) represent the largest membrane protein family and a significant target class for therapeutics. Receptors from GPCRs’ largest class, class A, influence virtually every aspect of human physiology. About 45% of the members of this family endogenously bind flexible peptides or peptides segments within larger protein ligands. While many of these peptides have been structurally characterized in their solution state, the few studies of peptides in their receptor-bound state suggest that these peptides interact with a shared set of residues and undergo significant conformational changes. For the purpose of understanding binding dynamics and the development of peptidomimetic drug compounds, further studies should investigate the peptide ligands that are complexed to their cognate receptor.
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Affiliation(s)
- Oanh Vu
- Deparment of Chemistry, Vanderbilt University, Nashville, TN 37235, USA;
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA; (B.J.B.); (L.P.)
| | - Brian Joseph Bender
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA; (B.J.B.); (L.P.)
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
| | - Lisa Pankewitz
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA; (B.J.B.); (L.P.)
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Medical Department, Leipzig University, Härtelstr. 16–18, D-04107 Leipzig, Germany;
| | - Annette G. Beck-Sickinger
- Faculty of Life Sciences, Institute of Biochemistry, Leipzig University, Brüderstr. 34, D-04103 Leipzig, Germany;
| | - Jens Meiler
- Deparment of Chemistry, Vanderbilt University, Nashville, TN 37235, USA;
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA; (B.J.B.); (L.P.)
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
- Leipzig University Medical Center, Institute for Drug Discovery, Departments of Chemistry and Computer Science, Leipzig University, Brüderstr. 34, D-04103 Leipzig, Germany
- Correspondence:
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4
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Testa C, D'Addona D, Scrima M, Tedeschi AM, D'Ursi AM, Bernhard C, Denat F, Bello C, Rovero P, Chorev M, Papini AM. Design, synthesis, and conformational studies of [DOTA]‐Octreotide analogs containing [1,2,3]triazolyl as a disulfide mimetic. Pept Sci (Hoboken) 2018. [DOI: 10.1002/pep2.24071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Chiara Testa
- French‐Italian Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of FlorenceSesto Fiorentino50019 Italy
- Department of Chemistry “Ugo Schiff”University of Florence, Via della Lastruccia 13Sesto Fiorentino50019 Italy
- PeptLab@UCP and Laboratory of Chemical Biology EA4505Université Paris‐Seine, 5 Mail Gay‐LussacCergy‐Pontoise95031 France
| | - Debora D'Addona
- French‐Italian Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of FlorenceSesto Fiorentino50019 Italy
- Department of Chemistry “Ugo Schiff”University of Florence, Via della Lastruccia 13Sesto Fiorentino50019 Italy
- ICMUB UMR6302, CNRS, Université Bourgogne Franche‐Comté, 9, Avenue Alain SavaryDijon21078 France
| | - Mario Scrima
- Department of Pharmaceutical SciencesUniversity of Salerno, Via Don Melillo 11CFisciano84084 Italy
| | - Anna Maria Tedeschi
- Department of Pharmaceutical SciencesUniversity of Salerno, Via Don Melillo 11CFisciano84084 Italy
| | - Anna Maria D'Ursi
- Department of Pharmaceutical SciencesUniversity of Salerno, Via Don Melillo 11CFisciano84084 Italy
| | - Claire Bernhard
- ICMUB UMR6302, CNRS, Université Bourgogne Franche‐Comté, 9, Avenue Alain SavaryDijon21078 France
| | - Franck Denat
- ICMUB UMR6302, CNRS, Université Bourgogne Franche‐Comté, 9, Avenue Alain SavaryDijon21078 France
| | - Claudia Bello
- French‐Italian Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of FlorenceSesto Fiorentino50019 Italy
- Department of Chemistry “Ugo Schiff”University of Florence, Via della Lastruccia 13Sesto Fiorentino50019 Italy
| | - Paolo Rovero
- French‐Italian Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of FlorenceSesto Fiorentino50019 Italy
- Department of Neurosciences, PsychologyDrug Research and Child Health, Section of Pharmaceutical Sciences and Nutraceutics, University of Florence, Via Ugo Schiff 6Sesto Fiorentino50019 Italy
| | - Michael Chorev
- Laboratory for Translational Research, Division of Hematology, Department of MedicineBrigham and Women's Hospital, Harvard Medical School, 75 Francis StreetBoston Massachusetts02115
| | - Anna Maria Papini
- French‐Italian Interdepartmental Laboratory of Peptide and Protein Chemistry and Biology, University of FlorenceSesto Fiorentino50019 Italy
- Department of Chemistry “Ugo Schiff”University of Florence, Via della Lastruccia 13Sesto Fiorentino50019 Italy
- PeptLab@UCP and Laboratory of Chemical Biology EA4505Université Paris‐Seine, 5 Mail Gay‐LussacCergy‐Pontoise95031 France
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5
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Pratesi A, Ginanneschi M, Lumini M, Papini AM, Novellino E, Brancaccio D, Carotenuto A. DOTA-Derivatives of Octreotide Dicarba-Analogs with High Affinity for Somatostatin sst 2,5 Receptors. Front Chem 2017; 5:8. [PMID: 28286746 PMCID: PMC5324734 DOI: 10.3389/fchem.2017.00008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 02/09/2017] [Indexed: 01/26/2023] Open
Abstract
In vivo somatostatin receptor scintigraphy is a valuable method for the visualization of human endocrine tumors and their metastases. In fact, peptide ligands of somatostatin receptors (sst's) conjugated with chelating agents are in clinical use. We have recently developed octreotide dicarba-analogs, which show interesting binding profiles at sst's. In this context, it was mandatory to explore the possibility that our analogs could maintain their activity also upon conjugation with DOTA. In this paper, we report and discuss the synthesis, binding affinity and conformational preferences of three DOTA-conjugated dicarba-analogs of octreotide. Interestingly, two conjugated analogs exhibited nanomolar affinities on sst2 and sst5 somatostatin receptor subtypes.
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Affiliation(s)
- Alessandro Pratesi
- Department of Chemistry "Ugo Schiff," University of Florence Firenze, Italy
| | - Mauro Ginanneschi
- Department of Chemistry "Ugo Schiff," University of FlorenceFirenze, Italy; Interdepartmental Laboratory of Peptide & Protein Chemistry & Biology, University of FlorenceFirenze, Italy
| | - Marco Lumini
- Department of Chemistry "Ugo Schiff," University of FlorenceFirenze, Italy; Interdepartmental Laboratory of Peptide & Protein Chemistry & Biology, University of FlorenceFirenze, Italy
| | - Anna M Papini
- Department of Chemistry "Ugo Schiff," University of FlorenceFirenze, Italy; Interdepartmental Laboratory of Peptide & Protein Chemistry & Biology, University of FlorenceFirenze, Italy
| | - Ettore Novellino
- Department of Pharmacy, University of Naples "Federico II" Naples, Italy
| | - Diego Brancaccio
- Department of Pharmacy, University of Naples "Federico II" Naples, Italy
| | - Alfonso Carotenuto
- Department of Pharmacy, University of Naples "Federico II" Naples, Italy
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6
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Van der Poorten O, Knuhtsen A, Sejer Pedersen D, Ballet S, Tourwé D. Side Chain Cyclized Aromatic Amino Acids: Great Tools as Local Constraints in Peptide and Peptidomimetic Design. J Med Chem 2016; 59:10865-10890. [PMID: 27690430 DOI: 10.1021/acs.jmedchem.6b01029] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Constraining the conformation of flexible peptides is a proven strategy to increase potency, selectivity, and metabolic stability. The focus has mostly been on constraining the backbone dihedral angles; however, the correct orientation of the amino acid side chains (χ-space) that constitute the peptide pharmacophore is equally important. Control of χ-space utilizes conformationally constrained amino acids that favor, disfavor, or exclude the gauche (-), the gauche (+), or the trans conformation. In this review we focus on cyclic aromatic amino acids in which the side chain is connected to the peptide backbone to provide control of χ1- and χ2-space. The manifold applications for cyclized analogues of the aromatic amino acids Phe, Tyr, Trp, and His within peptide medicinal chemistry are showcased herein with examples of enzyme inhibitors and ligands for G protein-coupled receptors.
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Affiliation(s)
- Olivier Van der Poorten
- Research Group of Organic Chemistry, Departments of Chemistry and Bio-Engineering Sciences, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium
| | - Astrid Knuhtsen
- Department of Drug Design and Pharmacology, University of Copenhagen , Jagtvej 162, 2100 Copenhagen, Denmark
| | - Daniel Sejer Pedersen
- Department of Drug Design and Pharmacology, University of Copenhagen , Jagtvej 162, 2100 Copenhagen, Denmark
| | - Steven Ballet
- Research Group of Organic Chemistry, Departments of Chemistry and Bio-Engineering Sciences, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium
| | - Dirk Tourwé
- Research Group of Organic Chemistry, Departments of Chemistry and Bio-Engineering Sciences, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium
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7
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Peptide aromatic interactions modulated by fluorinated residues: Synthesis, structure and biological activity of Somatostatin analogs containing 3-(3',5'difluorophenyl)-alanine. Sci Rep 2016; 6:27285. [PMID: 27271737 PMCID: PMC4895178 DOI: 10.1038/srep27285] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/17/2016] [Indexed: 12/18/2022] Open
Abstract
Somatostatin is a 14-residue peptide hormone that regulates the endocrine system by binding to five G-protein-coupled receptors (SSTR1–5). We have designed six new Somatostatin analogs with L-3-(3′,5′-difluorophenyl)-alanine (Dfp) as a substitute of Phe and studied the effect of an electron-poor aromatic ring in the network of aromatic interactions present in Somatostatin. Replacement of each of the Phe residues (positions 6, 7 and 11) by Dfp and use of a D-Trp8 yielded peptides whose main conformations could be characterized in aqueous solution by NMR. Receptor binding studies revealed that the analog with Dfp at position 7 displayed a remarkable affinity to SSTR2 and SSTR3. Analogs with Dfp at positions 6 or 11 displayed a π-π interaction with the Phe present at 11 or 6, respectively. Interestingly, these analogs, particularly [D-Trp8,L-Dfp11]-SRIF, showed high selectivity towards SSTR2, with a higher value than that of Octreotide and a similar one to that of native Somatostatin.
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8
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Stengel A, Karasawa H, Taché Y. The role of brain somatostatin receptor 2 in the regulation of feeding and drinking behavior. Horm Behav 2015; 73:15-22. [PMID: 26026616 PMCID: PMC4546908 DOI: 10.1016/j.yhbeh.2015.05.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 05/13/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
Somatostatin was discovered four decades ago as hypothalamic factor inhibiting growth hormone release. Subsequently, somatostatin was found to be widely distributed throughout the brain and to exert pleiotropic actions via interaction with five somatostatin receptors (sst1-5) that are also widely expressed throughout the brain. Interestingly, in contrast to the predominantly inhibitory actions of peripheral somatostatin, the activation of brain sst2 signaling by intracerebroventricular injection of stable somatostatin agonists potently stimulates food intake and independently, drinking behavior in rodents. The orexigenic response involves downstream orexin-1, neuropeptide Y1 and μ receptor signaling while the dipsogenic effect is mediated through the activation of the brain angiotensin 1 receptor. Brain sst2 activation is part of mechanisms underlying the stimulation of feeding and more prominently water intake in the dark phase and is able to counteract the anorexic response to visceral stressors.
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Affiliation(s)
- Andreas Stengel
- Charité Center for Internal Medicine and Dermatology, Division of General Internal and Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - Hiroshi Karasawa
- CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women's Health, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - Yvette Taché
- CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women's Health, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA.
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9
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Li G, Low PS. Synthesis and evaluation of a ligand targeting the somatostatin-2 receptor for drug delivery to neuroendocrine cancers. Bioorg Med Chem Lett 2015; 25:1792-1798. [PMID: 25791453 DOI: 10.1016/j.bmcl.2015.02.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 02/11/2015] [Accepted: 02/16/2015] [Indexed: 11/16/2022]
Abstract
Over-expression of the somatostatin-2 (SST2) receptor on plasma membranes of neuroendocrine cancer cells renders it attractive for use in targeting both imaging and therapeutic agents to neuroendocrine tumors. Peptide analogs of somatostatin have dominated this approach to date, however, many peptide analogs are either unstable in vivo or exhibit unwanted non-specific uptake in the liver and kidneys. The purpose of this Letter is to describe the preparation and evaluation of a non-peptide SST2 agonist for use in targeting drugs to neuroendocrine cancers. A non-peptide ligand for the SST2 receptor was identified from the literature as a candidate for development of targeted pharmaceuticals for neuroendocrine tumors, based on its SST2 binding affinity and selectivity for SST2 over other somatostatin receptors. It also offered a multiplicity of possible conjugation sites. Rhodamine conjugates in two positions were used for optical imaging and two compounds were internalized in an SST2 receptor transduced cell line (C6-SST2) via SST2 receptor-mediated endocytosis. Radionuclide conjugates were prepared for in vivo imaging and biodistribution studies in mice. The in vitro binding affinity of (99m)Tc conjugates ranged from a Kd of 37-494. Of these, one (99m)Tc conjugate was selected and dosed by IV injection into mice bearing C6-SST2 tumor xenografts. The highest uptake was into tumor, intestine and skin four hours after IV injection. Competition studies with octreotide, a synthetic peptide and SST2 agonist, confirmed that uptake was SST2 receptor mediated. While relatively high uptake in intestine, liver, kidneys and skin discouraged further development of the conjugate for delivery of chemotherapeutic agents, the conjugate may still be worthy of further development for neuroendocrine tumor imaging.
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Affiliation(s)
- Guo Li
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, United States
| | - Philip S Low
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, United States.
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10
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Mulak A, Larauche M, Biraud M, Million M, Rivier J, Taché Y. Selective agonists of somatostatin receptor subtype 1 or 2 injected peripherally induce antihyperalgesic effect in two models of visceral hypersensitivity in mice. Peptides 2015; 63:71-80. [PMID: 25451334 PMCID: PMC4385413 DOI: 10.1016/j.peptides.2014.10.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 10/27/2014] [Accepted: 10/28/2014] [Indexed: 02/08/2023]
Abstract
Somatostatin interacts with five G-protein-coupled receptor (sst1-5). Octreotide, a stable sst2≫3≥5 agonist, exerts a visceral anti-hyperalgesic effect in experimental and clinical studies. Little is known on the receptor subtypes involved. We investigated the influence of the stable sst1-5 agonist, ODT8-SST and selective receptor subtype peptide agonists (3 or 10μg/mouse) injected intraperitoneally (ip) on visceral hypersensitivity in mice induced by repeated noxious colorectal distensions (four sets of three CRD, each at 55mmHg) or corticotropin-releasing factor receptor 1 agonist, cortagine given between two sets of graded CRD (15, 30, 45, and 60mmHg, three times each pressure). The mean visceromotor response (VMR) was assessed using a non-invasive manometry method and values were expressed as percentage of the VMR to the 1st set of CRD baseline or to the 60mmHg CRD, respectively. ODT8-SST (10μg) and the sst2 agonist, S-346-011 (3 and 10μg) prevented mechanically induced visceral hypersensitivity in the three sets of CRD, the sst1 agonist (10μg) blocked only the 2nd set and showed a trend at 3μg while the sst4 agonist had no effect. The selective sst2 antagonist, S-406-028 blocked the sst2 agonist but not the sst1 agonist effect. The sst1 agonist (3 and 10μg) prevented cortagine-induced hypersensitivity to CRD at each pressure while the sst2 agonist at 10μg reduced it. These data indicate that in addition to sst2, the sst1 agonist may provide a novel promising target to alleviate visceral hypersensitivity induced by mechanoreceptor sensitization and more prominently, stress-related visceral nociceptive sensitization.
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Affiliation(s)
- Agata Mulak
- Department of Medicine, CURE: Digestive Diseases Research Center and Oppenheimer Family Center for Neurobiology of Stress, Digestive Diseases Division at the University of California Los Angeles and VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA; Department of Gastroenterology and Hepatology, Wroclaw Medical University, Wroclaw, Poland
| | - Muriel Larauche
- Department of Medicine, CURE: Digestive Diseases Research Center and Oppenheimer Family Center for Neurobiology of Stress, Digestive Diseases Division at the University of California Los Angeles and VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Mandy Biraud
- Department of Medicine, CURE: Digestive Diseases Research Center and Oppenheimer Family Center for Neurobiology of Stress, Digestive Diseases Division at the University of California Los Angeles and VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Mulugeta Million
- Department of Medicine, CURE: Digestive Diseases Research Center and Oppenheimer Family Center for Neurobiology of Stress, Digestive Diseases Division at the University of California Los Angeles and VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Jean Rivier
- The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, CA, USA
| | - Yvette Taché
- Department of Medicine, CURE: Digestive Diseases Research Center and Oppenheimer Family Center for Neurobiology of Stress, Digestive Diseases Division at the University of California Los Angeles and VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA.
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11
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Karasawa H, Yakabi S, Wang L, Stengel A, Rivier J, Taché Y. Brain somatostatin receptor 2 mediates the dipsogenic effect of central somatostatin and cortistatin in rats: role in drinking behavior. Am J Physiol Regul Integr Comp Physiol 2014; 307:R793-801. [PMID: 25031229 DOI: 10.1152/ajpregu.00248.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Intracerebroventricular injection of stable somatostatin (SST) agonists stimulates food and water intake in rats. We investigated the receptor subtype(s) involved in the dipsogenic effect of intracerebroventricular injection of SST agonists, mechanisms of action, and role. In nonfasted and non-water-deprived male rats with chronic intracerebroventricular cannula, intake of water without food or food without water was monitored separately to avoid any interactions compared with intracerebroventricular vehicle. SST-14 and cortistatin (CST-14) (1 μg/rat icv) increased water intake by 3.1- and 2.7-fold, respectively, while both peptides did not alter food intake at 1 h postinjection in the light phase. By contrast, the stable pan-somatostatin agonist ODT8-SST (1 μg/rat icv) increased both water and food intake by 4.9- and 3.7-fold, respectively. S-346-011, a selective receptor 2 (sst2) agonist (1 μg/rat icv) induced water ingestion, while sst1 or sst4 agonist, injected under the same conditions, did not. The sst2 antagonist S-406-028 (1 μg/rat icv) prevented the 1-h water intake induced by intracerebroventricular ODT8-SST and CST-14. Losartan (100 μg/rat icv), an angiotensin receptor 1 (AT1) antagonist, completely blocked the water consumption induced by intracerebroventricular ODT8-SST, whereas intracerebroventricular injection of S-406-028 did not modify the intracerebroventricular ANG II-induced dipsogenic response. The sst2 antagonist reduced by 40% the increase of the 3-h water intake in the early dark phase. These data indicate that SST-14 and CST-14 interact with sst2 to exert a potent dipsogenic effect, which is mediated downstream by angiotensin-AT1 signaling. These data also indicate that sst2 activation by brain SST-14 and/or CST-14 may play an important role in the regulation of drinking behavior.
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Affiliation(s)
- Hiroshi Karasawa
- Department of Medicine, CURE/Digestive Diseases Center, Digestive Diseases Division, University of California at Los Angeles, and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California; and
| | - Seiichi Yakabi
- Department of Medicine, CURE/Digestive Diseases Center, Digestive Diseases Division, University of California at Los Angeles, and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California; and
| | - Lixin Wang
- Department of Medicine, CURE/Digestive Diseases Center, Digestive Diseases Division, University of California at Los Angeles, and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California; and
| | - Andreas Stengel
- Department of Medicine, CURE/Digestive Diseases Center, Digestive Diseases Division, University of California at Los Angeles, and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California; and
| | - Jean Rivier
- The Clayton Foundation Laboratories for Peptide Biology, Salk Institute, La Jolla, California
| | - Yvette Taché
- Department of Medicine, CURE/Digestive Diseases Center, Digestive Diseases Division, University of California at Los Angeles, and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California; and
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12
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The production of recombinant 15N, 13C-labelled somatostatin 14 for NMR spectroscopy. Protein Expr Purif 2014; 99:78-86. [DOI: 10.1016/j.pep.2014.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 03/12/2014] [Accepted: 03/19/2014] [Indexed: 01/29/2023]
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13
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Martín-Gago P, Aragón E, Gomez-Caminals M, Fernández-Carneado J, Ramón R, Martin-Malpartida P, Verdaguer X, López-Ruiz P, Colás B, Cortes MA, Ponsati B, Macias MJ, Riera A. Insights into structure-activity relationships of somatostatin analogs containing mesitylalanine. Molecules 2013; 18:14564-84. [PMID: 24287991 PMCID: PMC6270305 DOI: 10.3390/molecules181214564] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 11/12/2013] [Accepted: 11/13/2013] [Indexed: 12/29/2022] Open
Abstract
The non-natural amino acid mesitylalanine (2,4,6-trimethyl-L-phenylalanine; Msa) has an electron-richer and a more conformationally restricted side-chain than that of its natural phenylalanine counterpart. Taking these properties into account, we have synthesized ten somatostatin analogs containing Msa residues in different key positions to modify the intrinsic conformational flexibility of the natural hormone. We have measured the binding affinity of these analogs and correlated it with the main conformations they populate in solution. NMR and computational analysis revealed that analogs containing one Msa residue were conformationally more restricted than somatostatin under similar experimental conditions. Furthermore, we were able to characterize the presence of a hairpin at the pharmacophore region and a non-covalent interaction between aromatic residues 6 and 11. In all cases, the inclusion of a D-Trp in the eighth position further stabilized the main conformation. Some of these peptides bound selectively to one or two somatostatin receptors with similar or even higher affinity than the natural hormone. However, we also found that multiple incorporations of Msa residues increased the life span of the peptides in serum but with a loss of conformational rigidity and binding affinity.
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Affiliation(s)
- Pablo Martín-Gago
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
| | - Eric Aragón
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
| | - Marc Gomez-Caminals
- BCN Peptides S.A. Pol.Ind. Els Vinyets-Els Fogars, Sector II. Ctra. Comarcal 244, Km. 22, 08777 Sant Quintí de Mediona, Barcelona 08777, Spain; E-Mails: (M.G.-C.); (J.F.-C.); (B.P.)
| | - Jimena Fernández-Carneado
- BCN Peptides S.A. Pol.Ind. Els Vinyets-Els Fogars, Sector II. Ctra. Comarcal 244, Km. 22, 08777 Sant Quintí de Mediona, Barcelona 08777, Spain; E-Mails: (M.G.-C.); (J.F.-C.); (B.P.)
| | - Rosario Ramón
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
- Departament de Química Orgànica, Universitat de Barcelona, Martí i Franqués, 1-11, Barcelona 08028, Spain
| | - Pau Martin-Malpartida
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
| | - Xavier Verdaguer
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
- Departament de Química Orgànica, Universitat de Barcelona, Martí i Franqués, 1-11, Barcelona 08028, Spain
| | - Pilar López-Ruiz
- Departamento de Bioquímica y Biología Molecular, Universidad de Alcalá de Henares, Facultad de Medicina, Madrid 28871, Spain; E-Mails: (P.L.-R.); (B.C.); (M.A.C.)
| | - Begoña Colás
- Departamento de Bioquímica y Biología Molecular, Universidad de Alcalá de Henares, Facultad de Medicina, Madrid 28871, Spain; E-Mails: (P.L.-R.); (B.C.); (M.A.C.)
| | - María Alicia Cortes
- Departamento de Bioquímica y Biología Molecular, Universidad de Alcalá de Henares, Facultad de Medicina, Madrid 28871, Spain; E-Mails: (P.L.-R.); (B.C.); (M.A.C.)
| | - Berta Ponsati
- BCN Peptides S.A. Pol.Ind. Els Vinyets-Els Fogars, Sector II. Ctra. Comarcal 244, Km. 22, 08777 Sant Quintí de Mediona, Barcelona 08777, Spain; E-Mails: (M.G.-C.); (J.F.-C.); (B.P.)
| | - Maria J. Macias
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluis Companys, 23, Barcelona 08010, Spain
- Authors to whom correspondence should be addressed; E-Mails: (M.J.M.); (A.R.); Tel.: +34-934-037-189 (M.J.M.); Fax: +34-934-047-095 (M.J.M.); Tel. +34-934-047-093 (A.R.); Fax: +34-934-047-095 (A.R)
| | - Antoni Riera
- Institute for Research in Biomedicine (IRB Barcelona) Baldiri Reixac, 10, Barcelona 08028, Spain; E-Mails: (P.M.-G.); (E.A.); (R.R.); (P.M.-M.); (X.V.)
- Departament de Química Orgànica, Universitat de Barcelona, Martí i Franqués, 1-11, Barcelona 08028, Spain
- Authors to whom correspondence should be addressed; E-Mails: (M.J.M.); (A.R.); Tel.: +34-934-037-189 (M.J.M.); Fax: +34-934-047-095 (M.J.M.); Tel. +34-934-047-093 (A.R.); Fax: +34-934-047-095 (A.R)
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14
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Stengel A, Rivier J, Taché Y. Central actions of somatostatin-28 and oligosomatostatin agonists to prevent components of the endocrine, autonomic and visceral responses to stress through interaction with different somatostatin receptor subtypes. Curr Pharm Des 2013; 19:98-105. [PMID: 22950508 DOI: 10.2174/13816128130114] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 07/30/2012] [Indexed: 01/23/2023]
Abstract
Somatostatin was discovered four decades ago and since then its physiological role has been extensively investigated, first in relation with its inhibitory effect on growth hormone secretion but soon it expanded to extrapituitary actions influencing various stressresponsive systems. Somatostatin is expressed in distinct brain nuclei and binds to five somatostatin receptor subtypes which are also widely expressed in the brain with a distinct distribution pattern. The last few years witnessed the discovery of highly selective peptide somatostatin receptor agonists and antagonists representing valuable tools to delineate the respective pathways of somatostatin signaling. Here we review the centrally mediated actions of somatostatin and related selective somatostatin receptor subtype agonists to influence the endocrine, autonomic, and visceral components of the stress response and basal behavior as well as thermogenesis.
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Affiliation(s)
- Andreas Stengel
- CURE: Digestive Diseases Research Center and Center for Neurovisceral Sciences & Women's Health, Digestive Diseases Division, David Geffen School of Medicine at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
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15
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Stengel A, Rivier J, Taché Y. Modulation of the adaptive response to stress by brain activation of selective somatostatin receptor subtypes. Peptides 2013; 42:70-7. [PMID: 23287111 PMCID: PMC3633742 DOI: 10.1016/j.peptides.2012.12.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 12/21/2012] [Accepted: 12/21/2012] [Indexed: 01/06/2023]
Abstract
Somatostatin-14 was discovered in 1973 in the hypothalamus as a peptide inhibiting growth hormone release. Somatostatin interacts with five receptor subtypes (sst(1-5)) which are widely distributed in the brain with a distinct, but overlapping, expression pattern. During the last few years, the development of highly selective peptide agonists and antagonists provided new insight to characterize the role of somatostatin receptor subtypes in the pleiotropic actions of somatostatin. Recent evidence in rodents indicates that the activation of selective somatostatin receptor subtypes in the brain blunts stress-corticotropin-releasing factor (CRF) related ACTH release (sst2/5), sympathetic-adrenal activaton (sst5), stimulation of colonic motility (sst1), delayed gastric emptying (sst5), suppression of food intake (sst2) and the anxiogenic-like (sst2) response. These findings suggest that brain somatostatin signaling pathways may play an important role in dampening CRF-mediated endocrine, sympathetic, behavioral and visceral responses to stress.
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Affiliation(s)
- Andreas Stengel
- CURE: Digestive Diseases Research Center and Center for Neurovisceral Sciences & Women's Health, Digestive Diseases Division, David Geffen School of Medicine at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
- Division of Psychosomatic Medicine & Obesity Center Berlin, Department of Medicine, Charité Medical Center and University, Berlin, Germany
| | - Jean Rivier
- Peptide Biology Laboratories, Salk Institute, La Jolla, California, USA
| | - Yvette Taché
- CURE: Digestive Diseases Research Center and Center for Neurovisceral Sciences & Women's Health, Digestive Diseases Division, David Geffen School of Medicine at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
- Address: CURE: Digestive Diseases Research Center, Building 115, Room 117, VA Greater Los Angeles Healthcare System, 11301 Wilshire Boulevard, Los Angeles, CA 90073, Phone: 310-312-9275, Fax: 1-310-268-4963,
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16
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Lesma G, Cecchi R, Cagnotto A, Gobbi M, Meneghetti F, Musolino M, Sacchetti A, Silvani A. Tetrahydro-β-carboline-based spirocyclic lactam as type II' β-turn: application to the synthesis and biological evaluation of somatostatine mimetics. J Org Chem 2013; 78:2600-10. [PMID: 23409740 DOI: 10.1021/jo302737j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The synthesis of novel spirocyclic lactams, embodying D-tryptophan (Trp) amino acid as the central core and acting as peptidomimetics, is presented. It relies on the strategic combination of Seebach's self-reproduction of chirality chemistry and Pictet-Spengler condensation as key steps. Investigation of the conformational behavior by molecular modeling, X-ray crystallography, and NMR and IR spectroscopies suggests very stable and highly predictable type II' β-turn conformations for all compounds. Relying on this feature, we also pursued their application to two potential mimetics of the hormone somatostatin, a pharmaceutically relevant natural peptide, which contains a Trp-based type II' β-turn pharmacophore.
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Affiliation(s)
- Giordano Lesma
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
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17
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Stengel A, Taché Y. Activation of somatostatin 2 receptors in the brain and the periphery induces opposite changes in circulating ghrelin levels: functional implications. Front Endocrinol (Lausanne) 2012; 3:178. [PMID: 23335913 PMCID: PMC3542632 DOI: 10.3389/fendo.2012.00178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 12/17/2012] [Indexed: 12/26/2022] Open
Abstract
Somatostatin is an important modulator of neurotransmission in the central nervous system and acts as a potent inhibitor of hormone and exocrine secretion and regulator of cell proliferation in the periphery. These pleiotropic actions occur through interaction with five G protein-coupled somatostatin receptor subtypes (sst(1) (-) (5)) that are widely expressed in the brain and peripheral organs. The characterization of somatostatin's effects can be investigated by pharmacological or genetic approaches using newly developed selective sst agonists and antagonists and mice lacking specific sst subtypes. Recent evidence points toward a divergent action of somatostatin in the brain and in the periphery to regulate circulating levels of ghrelin, an orexigenic hormone produced by the endocrine X/A-like cells in the rat gastric mucosa. Somatostatin interacts with the sst(2) in the brain to induce an increase in basal ghrelin plasma levels and counteracts the visceral stress-related decrease in circulating ghrelin. By contrast, stimulation of peripheral somatostatin-sst(2) signaling results in the inhibition of basal ghrelin release and mediates the postoperative decrease in circulating ghrelin. The peripheral sst(2)-mediated reduction of plasma ghrelin is likely to involve a paracrine action of D cell-derived somatostatin acting on sst(2) bearing X/A-like ghrelin cells in the gastric mucosa. The other member of the somatostatin family, named cortistatin, in addition to binding to sst(1) (-) (5) also directly interacts with the ghrelin receptor and therefore may simultaneously modulate ghrelin release and actions at target sites bearing ghrelin receptors representing a link between the ghrelin and somatostatin systems.
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Affiliation(s)
- Andreas Stengel
- Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Obesity Center Berlin, Charité, Universitätsmedizin BerlinBerlin, Germany
- *Correspondence: Andreas Stengel, Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Obesity Center Berlin, Charité, Universitätsmedizin Berlin, Luisenstr. 13a, 10117 Berlin, Germany. e-mail: ; Yvette Taché, Digestive Diseases Division, CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women’s Health, Department of Medicine, VA Greater Los Angeles Health Care System, University of California at Los Angeles, CURE Building 115, Room 117, 11301 Wilshire Boulevard, Los Angeles, CA 90073, USA. e-mail:
| | - Yvette Taché
- Digestive Diseases Division, CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women’s Health, Department of Medicine, VA Greater Los Angeles Health Care System, University of California at Los AngelesLos Angeles, CA, USA
- *Correspondence: Andreas Stengel, Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Obesity Center Berlin, Charité, Universitätsmedizin Berlin, Luisenstr. 13a, 10117 Berlin, Germany. e-mail: ; Yvette Taché, Digestive Diseases Division, CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women’s Health, Department of Medicine, VA Greater Los Angeles Health Care System, University of California at Los Angeles, CURE Building 115, Room 117, 11301 Wilshire Boulevard, Los Angeles, CA 90073, USA. e-mail:
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18
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Martín-Gago P, Gomez-Caminals M, Ramón R, Verdaguer X, Martin-Malpartida P, Aragón E, Fernández-Carneado J, Ponsati B, López-Ruiz P, Cortes MA, Colás B, Macias MJ, Riera A. Fine-tuning the π-π Aromatic Interactions in Peptides: Somatostatin Analogues Containing Mesityl Alanine. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201106406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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19
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Martín-Gago P, Gomez-Caminals M, Ramón R, Verdaguer X, Martin-Malpartida P, Aragón E, Fernández-Carneado J, Ponsati B, López-Ruiz P, Cortes MA, Colás B, Macias MJ, Riera A. Fine-tuning the π-π Aromatic Interactions in Peptides: Somatostatin Analogues Containing Mesityl Alanine. Angew Chem Int Ed Engl 2011; 51:1820-5. [DOI: 10.1002/anie.201106406] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Indexed: 01/04/2023]
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20
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Erchegyi J, Cescato R, Waser B, Rivier JE, Reubi JC. N-imidazolebenzyl-histidine substitution in somatostatin and in its octapeptide analogue modulates receptor selectivity and function. J Med Chem 2011; 54:5981-7. [PMID: 21806016 DOI: 10.1021/jm200307v] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Despite 3 decades of focused chemical, biological, structural, and clinical developments, unusual properties of somatostatin (SRIF, 1) analogues are still being uncovered. Here we report the unexpected functional properties of 1 and the octapeptide cyclo(3-14)H-Cys-Phe-Phe-Trp(8)-Lys-Thr-Phe-Cys-OH (somatostatin numbering; OLT-8, 9) substituted by imBzl-l- or -d-His at position 8. These analogues were tested for their binding affinity to the five human somatostatin receptors (sst(1-5)), as well as for their functional properties (or functionalities) in an sst(3) internalization assay and in an sst(3) luciferase reporter gene assay. While substitution of Trp(8) in somatostatin by imBzl-l- or -d-His(8) results in sst(3) selectivity, substitution of Trp(8) in the octapeptide 9 by imBzl-l- or -d-His(8) results in loss of binding affinity for sst(1,2,4,5) and a radical functional switch from agonist to antagonist.
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Affiliation(s)
- Judit Erchegyi
- The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, 10010 N. Torrey Pines Road, La Jolla, California 92037, USA
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21
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Stengel A, Goebel-Stengel M, Wang L, Shaikh A, Lambrecht NWG, Rivier J, Taché Y. Abdominal surgery inhibits circulating acyl ghrelin and ghrelin-O-acyltransferase levels in rats: role of the somatostatin receptor subtype 2. Am J Physiol Gastrointest Liver Physiol 2011; 301:G239-48. [PMID: 21636529 PMCID: PMC3154605 DOI: 10.1152/ajpgi.00018.2011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Clinical studies are evaluating the efficacy of synthetic ghrelin agonists in postoperative ileus management. However, the control of ghrelin secretion under conditions of postoperative gastric ileus is largely unknown. Peripheral somatostatin inhibits ghrelin secretion in animals and humans. We investigated the time course of ghrelin changes postsurgery in fasted rats and whether somatostatin receptor subtype 2 (sst(2)) signaling is involved. Abdominal surgery (laparotomy and 1-min cecal palpation) induced a rapid and long-lasting decrease in plasma acyl ghrelin levels as shown by the 64, 67, and 59% reduction at 0.5, 2, and 5 h postsurgery, respectively, compared with sham (anesthesia alone for 10 min, P < 0.05). Levels were partly recovered at 7 h and fully restored at 24 h. The percentage of acyl ghrelin reduction was significantly higher than that of desacyl ghrelin at 2 h postsurgery and not at any other time point. This was associated with a 48 and 23% decrease in gastric and plasma ghrelin-O-acyltransferase protein concentrations, respectively (P < 0.001). Ghrelin-positive cells in the oxyntic mucosa expressed sst(2a) receptor and the sst(2) agonist S-346-011 inhibited fasting acyl ghrelin levels by 64 and 77% at 0.5 and 2 h, respectively. The sst(2) antagonist S-406-028 prevented the abdominal surgery-induced decreased circulating acyl ghrelin but not the delayed gastric emptying assessed 0.5 h postinjection. These data show that activation of sst(2) receptor located on gastric X/A-like cells plays a key role in the rapid inhibition of circulating acyl ghrelin induced by abdominal surgery while not being primarily involved in the early phase of postoperative gastric ileus.
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Affiliation(s)
- Andreas Stengel
- 1Department of Medicine, CURE Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division at University of California Los Angeles and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles;
| | - Miriam Goebel-Stengel
- 1Department of Medicine, CURE Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division at University of California Los Angeles and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles;
| | - Lixin Wang
- 1Department of Medicine, CURE Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division at University of California Los Angeles and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles;
| | - Almaas Shaikh
- 1Department of Medicine, CURE Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division at University of California Los Angeles and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles;
| | - Nils W. G. Lambrecht
- 2Gastrointestinal Endocrinology, Veterans Affairs Long Beach Healthcare System, Long Beach; and
| | - Jean Rivier
- 3Peptide Biology Laboratories, Salk Institute, La Jolla, California
| | - Yvette Taché
- 1Department of Medicine, CURE Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division at University of California Los Angeles and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles;
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22
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STENGEL A, GOEBEL-STENGEL M, WANG L, LUCKEY A, HU E, RIVIER J, TACHÉ Y. Central administration of pan-somatostatin agonist ODT8-SST prevents abdominal surgery-induced inhibition of circulating ghrelin, food intake and gastric emptying in rats. Neurogastroenterol Motil 2011; 23:e294-308. [PMID: 21569179 PMCID: PMC3117963 DOI: 10.1111/j.1365-2982.2011.01721.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Activation of brain somatostatin receptors (sst(1-5) ) with the stable pan-sst(1-5) somatostatin agonist, ODT8-SST blocks acute stress and central corticotropin-releasing factor (CRF)-mediated activation of endocrine and adrenal sympathetic responses. Brain CRF signaling is involved in delaying gastric emptying (GE) immediately post surgery. We investigated whether activation of brain sst signaling pathways modulates surgical stress-induced inhibition of gastric emptying and food intake. METHODS Fasted rats were injected intracisternally (i.c.) with somatostatin agonists and underwent laparotomy and 1-min cecal palpation. Gastric emptying of a non-nutrient solution and circulating acyl and desacyl ghrelin levels were assessed 50min post surgery. Food intake was monitored for 24 h. KEY RESULTS The abdominal surgery-induced inhibition of GE (65%), food intake (73% at 2h) and plasma acyl ghrelin levels (67%) was completely prevented by ODT8-SST (1μg per rat, i.c.). The selective sst(5) agonist, BIM-23052 prevented surgery-induced delayed GE, whereas selective sst(1) , sst(2) , or sst(4) agonists had no effect. However, the selective sst(2) agonist, S-346-011 (1μg per rat, i.c.) counteracted the abdominal surgery-induced inhibition of acyl ghrelin and food intake but not the delayed GE. The ghrelin receptor antagonist, [D-Lys(3) ]-GHRP-6 (0.93mg kg(-1) , intraperitoneal, i.p.) blocked i.p. ghrelin-induced increased GE, while not influencing i.c. ODT8-SST-induced prevention of delayed GE and reduced food intake after surgery. CONCLUSIONS & INFERENCES ODT8-SST acts in the brain to prevent surgery-induced delayed GE likely via activating sst(5) . ODT8-SST and the sst(2) agonist prevent the abdominal surgery-induced decrease in food intake and plasma acyl ghrelin indicating dissociation between brain somatostatin signaling involved in preventing surgery-induced suppression of GE and feeding response.
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Affiliation(s)
- A. STENGEL
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - M. GOEBEL-STENGEL
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - L. WANG
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - A. LUCKEY
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - E. HU
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - J. RIVIER
- Peptide Biology Laboratories, Salk Institute, La Jolla, CA, USA
| | - Y. TACHÉ
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
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STENGEL A, GOEBEL-STENGEL M, WANG L, LARAUCHE M, RIVIER J, TACHÉ Y. Central somatostatin receptor 1 activation reverses acute stress-related alterations of gastric and colonic motor function in mice. Neurogastroenterol Motil 2011; 23:e223-36. [PMID: 21564422 PMCID: PMC3683311 DOI: 10.1111/j.1365-2982.2011.01706.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Corticotropin-releasing factor (CRF) signaling induced by stress is well established to delay gastric emptying (GE) and stimulate colonic functions. The somatostatin receptor (sst(1-5) ) agonist, ODT8-SST acts in the brain to inhibit stress-induced adrenocorticotropic hormone and epinephrine secretion. We investigated whether ODT8-SST acts in the brain to influence stress-related alterations of gastric and colonic motor function and sst receptor subtype(s) involved. METHODS Peptides were injected intracerebroventricularly (i.c.v.) under short isoflurane anesthesia and GE, fecal pellet output (FPO) and distal colonic motility monitored in conscious mice. KEY RESULTS The stress of acute anesthesia/vehicle i.c.v. injection reduced GE by 67% and increased defecation by 99% compared to non-injected controls. Both responses were abolished by ODT8-SST (1μg= 0.75nmol) or sst(1) agonist (0.65-1.95nmol). The sst(1) agonist (1.95nmol) also prevented the abdominal surgery-induced delayed GE. Octreotide (sst(2) >sst(5) > sst(3) ) and the sst(2) or sst(4) agonists (1μg=0.78 or 0.70nmol, respectively) injected i.c.v. did not influence FPO while i.c.v. somatostatin-28 mimicked ODT8-SST's effect. The ODT8-SST-induced increased food intake was inhibited by i.c.v. sst(2) antagonist while the reduced FPO was unchanged. ODT8-SST i.c.v. reduced distal colonic motility in semi-restrained mice compared with vehicle and blocked water avoidance- and i.c.v. CRF (0.5μg=0.09nmol)-induced stimulated FPO while a similar colonic secretomotor response to i.p. 5-hydroxytryptophane (10mgkg(-1) =36.4μmol kg(-1) ) was unaltered. Conclusions & Inferences ODT8-SST counteracts stress/i.c.v. CRF-related stimulation of colonic motor function and delayed GE which can be reproduced mainly by activation of sst(1) receptors. These data opens new insight to brain somatostatinergic signaling pathways interfering with brain circuitries involved in gut motor responses to acute stress.
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Affiliation(s)
- A. STENGEL
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - M. GOEBEL-STENGEL
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - L. WANG
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - M. LARAUCHE
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - J. RIVIER
- Peptide Biology Laboratories, Salk Institute, La Jolla, CA, USA
| | - Y. TACHÉ
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
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Robertson CR, Flynn SP, White HS, Bulaj G. Anticonvulsant neuropeptides as drug leads for neurological diseases. Nat Prod Rep 2011; 28:741-62. [PMID: 21340067 DOI: 10.1039/c0np00048e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Anticonvulsant neuropeptides are best known for their ability to suppress seizures and modulate pain pathways. Galanin, neuropeptide Y, somatostatin, neurotensin, dynorphin, among others, have been validated as potential first-in-class anti-epileptic or/and analgesic compounds in animal models of epilepsy and pain, but their therapeutic potential extends to other neurological indications, including neurodegenerative and psychatric disorders. Disease-modifying properties of neuropeptides make them even more attractive templates for developing new-generation neurotherapeutics. Arguably, efforts to transform this class of neuropeptides into drugs have been limited compared to those for other bioactive peptides. Key challenges in developing neuropeptide-based anticonvulsants are: to engineer optimal receptor-subtype selectivity, to improve metabolic stability and to enhance their bioavailability, including penetration across the blood–brain barrier (BBB). Here, we summarize advances toward developing systemically active and CNS-penetrant neuropeptide analogs. Two main objectives of this review are: (1) to provide an overview of structural and pharmacological properties for selected anticonvulsant neuropeptides and their analogs and (2) to encourage broader efforts to convert these endogenous natural products into drug leads for pain, epilepsy and other neurological diseases.
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Affiliation(s)
- Charles R Robertson
- College of Pharmacy, Department of Medicinal Chemistry, 421 Wakara Way, STE. 360 Salt Lake City, UT 84108, USA
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25
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Ramón R, Martín-Gago P, Verdaguer X, Macias MJ, Martin-Malpartida P, Fernández-Carneado J, Gomez-Caminals M, Ponsati B, López-Ruiz P, Cortés MA, Colás B, Riera A. SSTR1- and SSTR3-selective somatostatin analogues. Chembiochem 2011; 12:625-32. [PMID: 21259412 DOI: 10.1002/cbic.201000597] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Indexed: 01/21/2023]
Abstract
We prepared the two enantiomers of 3-(3'-quinolyl)-alanine (Qla, 1) in multigram scale by asymmetric hydrogenation. These amino acids, protected as Fmoc derivatives, were then used in the solid-phase synthesis of two new somatostatin 14 (SRIF-14) analogues 8 a and 8 b, tetradecapeptides in which the tryptophan residue (Trp8) is replaced by one of the two enantiomers of 3-(3'-quinolyl)-alanine (Qla8) and therefore lack the N--H bond in residue 8. The selectivity of these new analogues for the somatostatin receptors, SSTR1-5, was measured. Substitution with L-Qla8 yielded peptide 8 a, which was highly selective for SSTR1 and SSTR3, with an affinity similar to that of SRIF-14. Substitution by D-Qla gave the relatively selective analogue 8 b, which showed high affinity for SSTR3 and significant affinity for SSTR1, SSTR2 and SSTR5. The biological results demonstrate that bulky and electronically poor aromatic amino acids at position 8 are compatible with strong activity with SSTR1 and SSTR3. Remarkably, these high affinity levels were achieved with peptides in which the conformational mobility was increased with respect to that of SRIF-14. This observation suggests that conformational rigidity is not required, and might be detrimental to the interaction with receptors SSTR1 and SSTR3. The absence of an indole N proton in Qla8 might also contribute to the increased flexibility observed in these analogues.
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Affiliation(s)
- Rosario Ramón
- Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac, 10, 08028 Barcelona, Spain
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26
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Fridkin G, Maina T, Nock BA, Blat D, Lev-Goldman V, Scolnik Y, Kapitkovski A, Vachutinsky Y, Shechter Y, Levy Y. Intramolecular azo-bridge as a cystine disulfide bond surrogate: Somatostatin-14 and brain natriuretic peptide (BNP) analogs. Bioorg Med Chem 2011; 19:798-806. [DOI: 10.1016/j.bmc.2010.12.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 11/26/2010] [Accepted: 12/04/2010] [Indexed: 02/06/2023]
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Dannoon SF, Bigott-Hennkens HM, Ma L, Gallazzi F, Lewis MR, Jurisson SS. In vitro structure-activity relationship of Re-cyclized octreotide analogues. Nucl Med Biol 2010; 37:527-37. [PMID: 20610157 DOI: 10.1016/j.nucmedbio.2010.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 03/02/2010] [Accepted: 03/27/2010] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Development of radiolabeled octreotide analogues is of interest for targeting somatostatin receptor (SSTR)-positive tumors for diagnostic and therapeutic purposes. We are investigating a direct labeling approach for incorporation of a Re ion into octreotide analogues, where the peptide sequences are cyclized via coordination to Re rather than through a disulfide bridge. METHODS Various octreotide analogue sequences and coordination systems (e.g., S(2)N(2) and S(3)N) were synthesized and cyclized with nonradioactive Re. In vitro competitive binding assays with (111)In-DOTA-Tyr(3)-octreotide in AR42J rat pancreatic tumor cells yielded IC(50) values as a measure of SSTR affinity of the Re-cyclized analogues. Three-dimensional structures of Re-cyclized Tyr(3)-octreotate and its disulfide-bridged analogue were calculated from two-dimensional NMR experiments to visualize the effect of metal cyclization on the analogue's pharmacophore. RESULTS Only two of the 11 Re-cyclized analogues investigated showed moderate in vitro binding affinity toward somatostatin subtype 2 receptors. Three-dimensional molecular structures of Re- and disulfide-cyclized Tyr(3)-octreotate were calculated, and both of their pharmacophore turns appear to be very similar with minor differences due to metal coordination to the amide nitrogen of one of the pharmacophore amino acids. CONCLUSIONS Various Re-cyclized analogues were developed and analogue 4 had moderate affinity toward somatostatin subtype 2 receptors. In vitro stable studies that are in progress showed stable radiometal cyclization of octreotide analogues via NS(3) and N(2)S(2) coordination forming five- and six-membered chelate rings. In vivo biodistribution studies are underway of (99m)Tc-cyclized analogue 4.
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Affiliation(s)
- Shorouk F Dannoon
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
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28
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Stengel A, Goebel M, Wang L, Rivier J, Kobelt P, Mönnikes H, Taché Y. Activation of brain somatostatin 2 receptors stimulates feeding in mice: analysis of food intake microstructure. Physiol Behav 2010; 101:614-22. [PMID: 20851136 DOI: 10.1016/j.physbeh.2010.09.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 09/04/2010] [Accepted: 09/13/2010] [Indexed: 01/23/2023]
Abstract
We recently reported that the oligosomatostatin receptor agonist, ODT8-SST increases food intake in rats via the somatostatin 2 receptor (sst(2)). We characterized ingestive behavior following intracerebroventricular (icv) injection of a selective sst(2) agonist in freely fed mice during the light phase. The sst(2) agonist (0.01, 0.03, 0.1, 0.3 or 1μg/mouse) injected icv under short inhalation anesthesia dose-dependently increased cumulative light phase food intake over 4h compared to vehicle with a 3.1-times increase at 1μg/mouse (p<0.05). Likewise, the sst(2,3,5) agonist octreotide (0.3 or 1μg/mouse) dose-dependently increased 4-h food intake, whereas selective sst(1) or sst(4) agonists at 1μg/mouse did not. In vehicle-treated mice, high fat diet increased caloric intake/4h by 2.8-times compared to regular diet (p<0.05) and values were further increased 1.4-times/4h by the sst(2) agonist. Automated continuous assessment of food intake established a 6.6-times higher food intake during the dark phase due to increased number of meals, meal size, meal duration and rate of ingestion compared to non-treated mice during the light phase. During the first 4h post icv sst(2) agonist injection, mice had a 57% increase in number of meals with a 60% higher rate of ingestion, and a 61% reduction in inter-meal intervals, whereas meal sizes were not altered compared to vehicle. These data indicate that the activation of brain sst(2) receptors potently stimulates the light phase ingestive behavior under basal or high fat diet-stimulated conditions in mice. The shortened inter-meal interval suggests an inhibitory effect of the sst(2) agonist on "satiety", whereas "satiation" is not altered as indicated by normal meal size.
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Affiliation(s)
- Andreas Stengel
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and Veterans Affairs Greater Los Angeles Health Care System, CA 90073, USA
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29
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Stengel A, Goebel M, Wang L, Rivier J, Kobelt P, Monnikes H, Tache Y. Selective central activation of somatostatin receptor 2 increases food intake, grooming behavior and rectal temperature in rats. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY : AN OFFICIAL JOURNAL OF THE POLISH PHYSIOLOGICAL SOCIETY 2010; 61:399-407. [PMID: 20814067 PMCID: PMC4040268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 07/15/2010] [Indexed: 05/29/2023]
Abstract
The consequences of selective activation of brain somatostatin receptor-2 (sst2) were assessed using the sst2 agonist, des-AA(1,4-6,11-13)-[DPhe(2),Aph7(Cbm),DTrp(8)]-Cbm-SST-Thr-NH2. Food intake (FI) was monitored in ad libitum fed rats chronically implanted with an intracerebroventricular (i.c.v.) cannula. The sst(2) agonist injected i.c.v. at 0.1 and 1 microg/rat dose-dependently increased light phase FI from 2 to 6 hours post injection (2.3+/-0.5 and 7.5+/-1.2 respectively vs. vehicle: 0.2+/-0.2 g/300 g bw, P<0.001). Peptide action was reversed by i.c.v. injection of the sst2 antagonist, des-AA(1,4-6,11-13)-[pNO(2)-Phe(2),DCys(3),Tyr(7),DAph(Cbm)8]-SST-2Nal-NH(2) and not reproduced by intraperitoneal injection (30 microg/rat). The sst(2) antagonist alone i.c.v. significantly decreased the cumulative 14-hours dark phase FI by 29.5%. Other behaviors, namely grooming, drinking and locomotor activity were also increased by the sst(2) agonist (1 microg/rat, i.c.v.) as monitored during the 2(nd) hour post injection while gastric emptying of solid food was unaltered. Rectal temperature rose 1 hour after the sst(2) agonist (1 microg/rat, i.c.v.) with a maximal response maintained from 1 to 4 hours post injection. These data show that selective activation of the brain sst(2) receptor induces a feeding response in the light phase not associated with changes in gastric emptying. The food intake reduction following sst(2) receptor blockade suggests a role of this receptor in the orexigenic drive during the dark phase.
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Affiliation(s)
- A Stengel
- CURE: Digestive Diseases Research Center and Center for Neurobiology of Stress, Department of Medicine, Digestive Diseases Division University of California Los Angeles and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
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Di Cianni A, Carotenuto A, Brancaccio D, Novellino E, Reubi JC, Beetschen K, Papini AM, Ginanneschi M. Novel Octreotide Dicarba-analogues with High Affinity and Different Selectivity for Somatostatin Receptors. J Med Chem 2010; 53:6188-97. [DOI: 10.1021/jm1005868] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Alessandra Di Cianni
- Laboratory of Peptides & Proteins, Chemistry & Biology, University of Firenze, Via della Lastruccia 13, I-50019 Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Firenze, Via della Lastruccia 5-13, I-50019, Sesto Fiorentino, Italy
| | - Alfonso Carotenuto
- Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, I-80131 Napoli, Italy
| | - Diego Brancaccio
- Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, I-80131 Napoli, Italy
| | - Ettore Novellino
- Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, I-80131 Napoli, Italy
| | - Jean Claude Reubi
- Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31, CH-3010 Berne, Switzerland
| | - Karin Beetschen
- Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31, CH-3010 Berne, Switzerland
| | - Anna Maria Papini
- Laboratory of Peptides & Proteins, Chemistry & Biology, University of Firenze, Via della Lastruccia 13, I-50019 Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Firenze, Via della Lastruccia 5-13, I-50019, Sesto Fiorentino, Italy
| | - Mauro Ginanneschi
- Laboratory of Peptides & Proteins, Chemistry & Biology, University of Firenze, Via della Lastruccia 13, I-50019 Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Firenze, Via della Lastruccia 5-13, I-50019, Sesto Fiorentino, Italy
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Goebel M, Stengel A, Wang L, Coskun T, Alsina-Fernandez J, Rivier J, Taché Y. Pattern of Fos expression in the brain induced by selective activation of somatostatin receptor 2 in rats. Brain Res 2010; 1351:150-164. [PMID: 20637739 DOI: 10.1016/j.brainres.2010.07.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Revised: 06/28/2010] [Accepted: 07/08/2010] [Indexed: 02/08/2023]
Abstract
Central activation of somatostatin (sst) receptors by oligosomatostatin analogs inhibits growth hormone and stress-related rise in catecholamine plasma levels while stimulating grooming, feeding behaviors, gastric transit and acid secretion, which can be mimicked by selective sst(2) receptor agonist. To evaluate the pattern of neuronal activation induced by peptide sst receptor agonists, we assessed Fos-expression in rat brain after intracerebroventricular (i.c.v.) injection of a newly developed selective sst(2) agonist compared to the oligosomatostatin ODT8-SST, a pan-sst(1-5) agonist. Ninety min after injection of vehicle (10 microl) or previously established maximal orexigenic dose of peptides (1 microg=1 nmol/rat), brains were assessed for Fos-immunohistochemistry and doublelabeling. Food and water were removed after injection. The sst(2) agonist and ODT8-SST induced a similar Fos distribution pattern except in the arcuate nucleus where only the sst(2) agonist increased Fos. Compared to ODT8-SST, the sst(2) agonist induced higher Fos-expression by 3.7-times in the basolateral amygdaloid nucleus, 1.2-times in the supraoptic nucleus (SON), 1.6-times in the magnocellular paraventricular hypothalamic nucleus (mPVN), 4.1-times in the external lateral parabrachial nucleus, and 2.6-times in both the inferior olivary nucleus and superficial layer of the caudal spinal trigeminal nucleus. Doublelabeling in the hypothalamus showed that ODT8-SST activates 36% of oxytocin, 63% of vasopressin and 79% of sst(2) immunoreactive neurons in the mPVN and 28%, 55% and 25% in the SON, respectively. Selective activation of sst(2) receptor results in a more robust neuronal activation than the pan-sst(1-5) agonist in various brain regions that may have relevance in sst(2) mediated alterations of behavioral, autonomic and endocrine functions.
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Affiliation(s)
- Miriam Goebel
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Andreas Stengel
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Lixin Wang
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Tamer Coskun
- Biotechnology Discovery Research, Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Jean Rivier
- Peptide Biology Laboratories, Salk Institute, La Jolla, CA, USA
| | - Yvette Taché
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.
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Ovadia O, Greenberg S, Laufer B, Gilon C, Hoffman A, Kessler H. Improvement of drug-like properties of peptides: the somatostatin paradigm. Expert Opin Drug Discov 2010; 5:655-71. [DOI: 10.1517/17460441.2010.493935] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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33
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Pérez de Vega MJ, García-Aranda MI, González-Muñiz R. A role for ring-closing metathesis in medicinal chemistry: Mimicking secondary architectures in bioactive peptides. Med Res Rev 2010; 31:677-715. [DOI: 10.1002/med.20199] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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34
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Erchegyi J, Cescato R, Grace CRR, Waser B, Piccand V, Hoyer D, Riek R, Rivier JE, Reubi JC. Novel, potent, and radio-iodinatable somatostatin receptor 1 (sst1) selective analogues. J Med Chem 2009; 52:2733-46. [PMID: 19351180 DOI: 10.1021/jm801314f] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The proposed sst(1) pharmacophore (J. Med. Chem. 2005, 48, 523-533) derived from the NMR structures of a family of mono- and dicyclic undecamers was used to design octa-, hepta-, and hexamers with high affinity and selectivity for the somatostatin sst(1) receptor. These compounds were tested for their in vitro binding properties to all five somatostatin (SRIF) receptors using receptor autoradiography; those with high SRIF receptor subtype 1 (sst(1)) affinity and selectivity were shown to be agonists when tested functionally in a luciferase reporter gene assay. Des-AA(1,4-6,10,12,13)-[DTyr(2),DAgl(NMe,2naphthoyl)(8),IAmp(9)]-SRIF-Thr-NH(2) (25) was radio-iodinated ((125)I-25) and specifically labeled sst(1)-expressing cells and tissues. 3D NMR structures were calculated for des-AA(1,4-6,10,12,13)-[DPhe(2),DTrp(8),IAmp(9)]-SRIF-Thr-NH(2) (16), des-AA(1,2,4-6,10,12,13)-[DAgl(NMe,2naphthoyl)(8),IAmp(9)]-SRIF-Thr-NH(2) (23), and des-AA(1,2,4-6,10,12,13)-[DAgl(NMe,2naphthoyl)(8),IAmp(9),Tyr(11)]-SRIF-NH(2) (27) in DMSO. Though the analogues have the sst(1) pharmacophore residues at the previously determined distances from each other, the positioning of the aromatic residues in 16, 23, and 27 is different from that described earlier, suggesting an induced fit mechanism for sst(1) binding of these novel, less constrained sst(1)-selective family members.
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Affiliation(s)
- Judit Erchegyi
- The Clayton Foundation Laboratories for Peptide Biology, La Jolla, California 92037, USA
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35
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Grace CRR, Erchegyi J, Reubi JC, Rivier JE, Riek R. Three-dimensional consensus structure of sst2-selective somatostatin (SRIF) antagonists by NMR. Biopolymers 2008; 89:1077-87. [PMID: 18655144 DOI: 10.1002/bip.21060] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The three-dimensional NMR structures of seven octapeptide analogs of somatostatin (SRIF), based on octreotide, with the basic sequence H-Cpa/Phe2-c[DCys3-Xxx7-DTrp/DAph(Cbm)8-Lys9-Thr10-Cys14]-Yyy-NH2 (the numbering refers to the position in native SRIF), with Xxx7 being Aph(Cbm)/Tyr/Agl(NMe,benzoyl) and Yyy being Nal/DTyr/Thr, are presented here. Most of these analogs exhibit potent and highly selective binding to sst2 receptors, and all of the analogs are antagonists inhibiting receptor signaling. Based on their consensus 3D structure, the pharmacophore of the sst2-selective antagonist has been defined. The pharmacophore involves the side chains of Cpa2, DTrp/DAph(Cbm)8, and Lys9, with the backbone for most of the sst2-selective antagonists comprised a Type-II' beta-turn. Hence, the sst2-selective antagonist pharmacophore is very similar to the sst2-selective agonist pharmacophore previously described.
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Affiliation(s)
- Christy Rani R Grace
- Structural Biology Laboratory, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
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36
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Feytens D, De Vlaeminck M, Cescato R, Tourwé D, Reubi JC. Highly Potent 4-Amino-indolo[2,3-c]azepin-3-one-Containing Somatostatin Mimetics with a Range of sst Receptor Selectivities. J Med Chem 2008; 52:95-104. [DOI: 10.1021/jm801205x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Debby Feytens
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland
| | - Magali De Vlaeminck
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland
| | - Renzo Cescato
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland
| | - Dirk Tourwé
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland
| | - Jean Claude Reubi
- Department of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland
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Seebach D, Dubost E, Mathad R, Jaun B, Limbach M, Löweneck M, Flögel O, Gardiner J, Capone S, Beck A, Widmer H, Langenegger D, Monna D, Hoyer D. New Open-Chain and Cyclic Tetrapeptides, Consisting ofα-,β2-, andβ3-Amino-Acid Residues, as Somatostatin Mimics - A Survey. Helv Chim Acta 2008. [DOI: 10.1002/hlca.200890190] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Cescato R, Erchegyi J, Waser B, Piccand V, Maecke HR, Rivier JE, Reubi JC. Design and in vitro characterization of highly sst2-selective somatostatin antagonists suitable for radiotargeting. J Med Chem 2008; 51:4030-7. [PMID: 18543899 DOI: 10.1021/jm701618q] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Radiolabeled sst 2 and sst 3 antagonists are better candidates for tumor targeting than agonists with comparable binding characteristics (Ginj, M.; Zhang, H.; Waser, B.; Cescato, R.; Wild, D.; Erchegyi, J.; Rivier, J.; Mäcke, H. R.; Reubi, J. C. Proc. Natl. Acad. Sci. U.S.A. 2006, 103, 16436-16441.). Because most of the neuroendocrine tumors express sst 2, we used the known antagonists acetyl- pNO 2Phe (2)- c[ dCys (3)-Tyr (7)- dTrp (8)-Lys (9)-Thr (10)-Cys (14)]- dTyr (15)-NH 2 ( 1) (Bass, R. T.; Buckwalter, B. L.; Patel, B. P.; Pausch, M. H.; Price, L. A.; Strnad, J.; Hadcock, J. R. Mol. Pharmacol. 1996, 50, 709-715. Bass, R. T.; Buckwalter, B. L.; Patel, B. P.; Pausch, M. H.; Price, L. A.; Strnad, J.; Hadcock, J. R. Mol. Pharmacol. 1997, 51, 170; Erratum.) and H-Cpa (2)- c[ dCys (3)-Tyr (7)- dTrp (8)-Lys (9)-Thr (10)-Cys (14)]-2Nal (15)-NH 2 ( 7) (Hocart, S. J.; Jain, R.; Murphy, W. A.; Taylor, J. E.; Coy, D. H. J. Med. Chem. 1999, 42, 1863-1871.) as leads for analogues with increased sst 2 binding affinity and selectivity. Among the 32 analogues reported here, DOTA- pNO 2Phe (2)- c[ dCys (3)-Tyr (7)- dAph (8)(Cbm)-Lys (9)-Thr (10)-Cys (14)- dTyr (15)-NH 2 ( 3) and DOTA-Cpa (2)- c[ dCys (3)-Aph (7)(Hor)- dAph (8)(Cbm)-Lys (9)-Thr (10)-Cys (14)]- dTyr (15)-NH 2 ( 31) had the highest sst 2 binding affinity and selectivity. All of the analogues tested kept their sst 2 antagonistic properties (i.e., did not affect calcium release in vitro and competitively antagonized the agonistic effect of [Tyr (3)]octreotide). Moreover, in an immunofluorescence-based internalization assay, the new analogues prevented sst 2 internalization induced by the sst 2 agonist [Tyr (3)]octreotide without being active by themselves. In conclusion, several analogues (in particular 3, 31, and 32) have outstanding sst 2 binding and functional antagonistic properties and, because of their DOTA moiety, are excellent candidates for in vivo targeting of sst 2-expressing cancers.
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Affiliation(s)
- Renzo Cescato
- Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland
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Erchegyi J, Grace CRR, Samant M, Cescato R, Piccand V, Riek R, Reubi JC, Rivier JE. Ring size of somatostatin analogues (ODT-8) modulates receptor selectivity and binding affinity. J Med Chem 2008; 51:2668-75. [PMID: 18410084 PMCID: PMC2782568 DOI: 10.1021/jm701444y] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The synthesis, biological testing, and NMR studies of several analogues of H-c[Cys (3)-Phe (6)-Phe (7)-DTrp (8)-Lys (9)-Thr (10)-Phe (11)-Cys (14)]-OH (ODT-8, a pan-somatostatin analogue, 1) have been performed to assess the effect of changing the stereochemistry and the number of atoms in the disulfide bridge on binding affinity. Cysteine at positions 3 and/or 14 (somatostatin numbering) were/was substituted with d-cysteine, norcysteine, D-norcysteine, homocysteine, and/or D-homocysteine. The 3D structure analysis of selected partially selective, bioactive analogues (3, 18, 19, and 21) was carried out in dimethylsulfoxide. Interestingly and not unexpectedly, the 3D structures of these analogues comprised the pharmacophore for which the analogues had the highest binding affinities (i.e., sst 4 in all cases).
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Affiliation(s)
- Judit Erchegyi
- The Clayton Foundation Laboratories for Peptide Biology and Structural Biology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
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Grace CRR, Erchegyi J, Samant M, Cescato R, Piccand V, Riek R, Reubi JC, Rivier JE. Ring size in octreotide amide modulates differently agonist versus antagonist binding affinity and selectivity. J Med Chem 2008; 51:2676-81. [PMID: 18410083 DOI: 10.1021/jm701445q] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
H-DPhe (2)-c[Cys (3)-Phe (7)-DTrp (8)-Lys (9)-Thr (10)-Cys (14)]-Thr (15)-NH2 (1) (a somatostatin agonist, SRIF numbering) and H-Cpa (2)-c[DCys (3)-Tyr (7)-DTrp (8)-Lys (9)-Thr (10)-Cys (14)]-Nal (15)-NH2 (4) (a somatostatin antagonist) are based on the structure of octreotide that binds to three somatostatin receptor subtypes (sst 2/3/5) with significant binding affinity. Analogues of 1 and 4 were synthesized with norcysteine (Ncy), homocysteine (Hcy), or D-homocysteine (DHcy) at positions 3 and/or 14. Introducing Ncy at positions 3 and 14 constrained the backbone flexibility, resulting in loss of binding affinity at all sst s. The introduction of Hcy at positions 3 and 14 improved selectivity for sst 2 as a result of significant loss of binding affinity at the other sst s. Substitution by DHcy at position 3 in the antagonist scaffold (5), on the other hand, resulted in a significant loss of binding affinity at sst 2 and sst 3 as compared to the different affinities of the parent compound (4). The 3D NMR structures of the analogues in dimethylsulfoxide are consistent with the observed binding affinities.
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Affiliation(s)
- Christy Rani R Grace
- Structural Biology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
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D’Addona D, Carotenuto A, Novellino E, Piccand V, Reubi JC, Di Cianni A, Gori F, Papini AM, Ginanneschi M. Novel sst5-Selective Somatostatin Dicarba-Analogues: Synthesis and Conformation−Affinity Relationships. J Med Chem 2008; 51:512-20. [DOI: 10.1021/jm070886i] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Debora D’Addona
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Alfonso Carotenuto
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Ettore Novellino
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Véronique Piccand
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Jean Claude Reubi
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Alessandra Di Cianni
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Francesca Gori
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Anna Maria Papini
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
| | - Mauro Ginanneschi
- Laboratory of Peptides and Proteins, Chemistry and Biology, Department of Organic Chemistry, University of Firenze, Via Lastruccia 13 I-50019, Sesto Fiorentino, Italy, Department of Pharmaceutical Chemistry and Toxicology, University of Napoli, Via Domenico Montesano 49, Italy, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Murtenstrasse 31 CH-3010 Berne, Switzerland, and Laboratory of Peptides and Proteins, Chemistry and Biology, Department of
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Grace CRR, Cervini L, Gulyas J, Rivier J, Riek R. Astressin-amide and astressin-acid are structurally different in dimethylsulfoxide. Biopolymers 2007; 87:196-205. [PMID: 17657708 DOI: 10.1002/bip.20818] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The C-terminally amidated CRF antagonist astressin binds to CRF-R1 or CRF-R2 receptors with low nanomolar affinity while the corresponding astressin-acid has >100 times less affinity. To understand the role of the amide group in binding, the conformations of astressin-amide and astressin-acid were studied in DMSO using NMR techniques. The 3D NMR structures show that the backbones of both analogs prefer an alpha-helical conformation, with a small kink around Gln(26). However, astressin-amide has a well-defined helical structure from Leu(27) to Ile(41) and a conformation very similar to the bioactive conformation reported by our group (Grace et al., Proc Natl Acad Sci USA 2007, 104, 4858-4863). In contrast, astressin-acid has an irregular helical conformation from Arg(35) onward, including a rearrangement of the side chains in that region. This structural difference highlights the crucial role of the C-terminal amidation for stabilization of astressin's bioactive conformation.
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Affiliation(s)
- Christy Rani R Grace
- Structural Biology Laboratory, The Salk Institute for Biological Studies, LA Jolla, CA 92037, USA
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Nikiforovich GV, Marshall GR, Achilefu S. Molecular modeling suggests conformational scaffolds specifically targeting five subtypes of somatostatin receptors. Chem Biol Drug Des 2007; 69:163-9. [PMID: 17441902 DOI: 10.1111/j.1747-0285.2007.00493.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Several analogs of somatostatin with conformational constraints in their peptide backbones have been modeled to determine energetically feasible conformations. Comparison of low-energy backbone structures of these peptides suggested unique conformations of the central Phe/Ala(i)-D-Trp(i+1)-Lys(i+2)-Thr(i+3) fragment characteristic for specific interactions of somatostatin with each of the five distinct subtypes of somatostatin receptors (SSTRs). The conformations obtained were in good agreement with experimental data obtained earlier by NMR measurements and/or X-ray crystallography. The results help rationalize experimental observations on the specificity of binding of various somatostatin analogs with different subtypes of the SSTRs. They also serve as templates for the design of conformationally constrained non-peptide scaffolds that effectively and selectively interact with different subtypes of SSTRs. Such scaffolds can be convenient carriers of radiolabels and near-infrared labels in specific agents for imaging tumors expressing different SSTR subtypes.
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Affiliation(s)
- Gregory V Nikiforovich
- Department of Biochemistry and Molecular Biology, Washington University Medical School, St. Louis, MO 63110, USA.
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