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Cavalcanti DMLP, Teófilo TS, D Rodrigues T, Barbosa TNS, Fontenele-Neto JD. Thimet oligopeptidase (THOP 1) distribution in cane toad (Bufo Marinus, Linnaeus, 1758) brain. J Chem Neuroanat 2023; 133:102345. [PMID: 37778734 DOI: 10.1016/j.jchemneu.2023.102345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/28/2023] [Accepted: 09/29/2023] [Indexed: 10/03/2023]
Abstract
Thimet oligopeptides (THOP 1) is a metal-dependent peptidase involved in the metabolism of neuropeptides and the presentation of peptides via MHC-1. It has been shown to play a role in the regulation of protein-protein interactions and the metabolism of intracellular peptides. THOP 1 is associated with important biological processes such as metabolism and neurodegenerative diseases, among others. The objective of this study is to elucidate the distribution of THOP 1 in the Bufo marinus brain. The analysis of THOP 1 amino acid sequences indicates that they have been conserved throughout evolution, with significant homology observed across various phyla. When comparing amphibians with other species, more than 70% identity can be identified. Immunohistochemistry analysis of the toad's brain has demonstrated that the enzyme has a ubiquitous distribution, consistent with previous findings in mammals. THOP 1 can be found in important areas of the brain, such as bulb, thalamic nuclei, striatum, hypothalamus, and among others. Nonetheless, THOP 1 is consistently localized within the nucleus, a pattern also observed in the rat brain. Therefore, based on these results, the toad appears to be an excellent model for studying the general biology of THOP 1, given the substantial homology of this enzyme with mammals and its similarity in distribution within the brain.
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Affiliation(s)
- Diogo M L P Cavalcanti
- Laboratory of Tissue and Development Biology, Medicine College, Department of Health Science, Center for Biological and Health Sciences, Universidade Federal Rural do Semiárido - UFERSA, Brazil.
| | - Tiago S Teófilo
- Laboratory of Tissue and Development Biology, Medicine College, Department of Health Science, Center for Biological and Health Sciences, Universidade Federal Rural do Semiárido - UFERSA, Brazil
| | - Tayline D Rodrigues
- Master's Degree Students, Multicentric Graduate Program in the area of Biochemistry and Molecular Biology (PMBqBM), Universidade do Estado do Rio Grande do Norte - UERN, Brazil
| | - Tayssa N S Barbosa
- Master's Degree Students, Multicentric Graduate Program in the area of Biochemistry and Molecular Biology (PMBqBM), Universidade do Estado do Rio Grande do Norte - UERN, Brazil
| | - José D Fontenele-Neto
- Laboratory of Tissue and Development Biology, Veterinary Medicine College, Department of Animal Science, Center for Biological and Health Sciences, Universidade Federal Rural do Semiárido - UFERSA, Brazil
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2
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Casazza A, Van Helleputte L, Van Renterghem B, Pokreisz P, De Geest N, De Petrini M, Janssens T, Pellens M, Diricx M, Riera-Domingo C, Wozniak A, Mazzone M, Schöffski P, Defert O, Reyns G, Kindt N. PhAc-ALGP-Dox, a Novel Anticancer Prodrug with Targeted Activation and Improved Therapeutic Index. Mol Cancer Ther 2022; 21:568-581. [PMID: 35149549 PMCID: PMC9377749 DOI: 10.1158/1535-7163.mct-21-0518] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 11/13/2021] [Accepted: 02/08/2022] [Indexed: 01/07/2023]
Abstract
Clinical use of doxorubicin (Dox) is limited by cumulative myelo- and cardiotoxicity. This research focuses on the detailed characterization of PhAc-ALGP-Dox, a targeted tetrapeptide prodrug with a unique dual-step activation mechanism, designed to circumvent Dox-related toxicities and is ready for upcoming clinical investigation. Coupling Dox to a phosphonoacetyl (PhAc)-capped tetrapeptide forms the cell-impermeable, inactive compound, PhAc-ALGP-Dox. After extracellular cleavage by tumor-enriched thimet oligopeptidase-1 (THOP1), a cell-permeable but still biologically inactive dipeptide-conjugate is formed (GP-Dox), which is further processed intracellularly to Dox by fibroblast activation protein-alpha (FAPα) and/or dipeptidyl peptidase-4 (DPP4). In vitro, PhAc-ALGP-Dox is effective in various 2D- and 3D-cancer models, while showing improved safety toward normal epithelium, hematopoietic progenitors, and cardiomyocytes. In vivo, these results translate into a 10-fold higher tolerability and 5-fold greater retention of Dox in the tumor microenvironment compared with the parental drug. PhAc-ALGP-Dox demonstrates 63% to 96% tumor growth inhibition in preclinical models, an 8-fold improvement in efficacy in patient-derived xenograft (PDX) models, and reduced metastatic burden in a murine model of experimental lung metastasis, improving survival by 30%. The current findings highlight the potential clinical benefit of PhAc-ALGP-Dox, a targeted drug-conjugate with broad applicability, favorable tissue biodistribution, significantly improved tolerability, and tumor growth inhibition at primary and metastatic sites in numerous solid tumor models.
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Affiliation(s)
- Andrea Casazza
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | | | - Britt Van Renterghem
- Laboratory of Experimental Oncology, Department of Oncology, KU Leuven, Leuven, Belgium
| | - Peter Pokreisz
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Natalie De Geest
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Marzia De Petrini
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Tom Janssens
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Marijke Pellens
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Marjan Diricx
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Carla Riera-Domingo
- Laboratory of Tumor Inflammation and Angiogenesis, Vesalius Research Center, VIB, Leuven, Belgium.,Laboratory of Tumor Inflammation and Angiogenesis, Department of Oncology, KU Leuven, Leuven, Belgium
| | - Agnieszka Wozniak
- Laboratory of Experimental Oncology, Department of Oncology, KU Leuven, Leuven, Belgium
| | - Massimiliano Mazzone
- Laboratory of Tumor Inflammation and Angiogenesis, Vesalius Research Center, VIB, Leuven, Belgium.,Laboratory of Tumor Inflammation and Angiogenesis, Department of Oncology, KU Leuven, Leuven, Belgium
| | - Patrick Schöffski
- Laboratory of Experimental Oncology, Department of Oncology, KU Leuven, Leuven, Belgium.,Department of General Medical Oncology, University Hospitals Leuven, Leuven Cancer Institute, Leuven, Belgium
| | - Olivier Defert
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Geert Reyns
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium
| | - Nele Kindt
- CoBioRes NV, Campus Gasthuisberg University of Leuven, Leuven, Belgium.,Corresponding Author: Nele Kindt, CoBioRes NV, Campus Gasthuisberg, CDG, bus 913 Herestraat 49, Leuven, Flanders B-3000, Belgium. E-mail:
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Gewehr MCF, Teixeira AAS, Santos BAC, Biondo LA, Gozzo FC, Cordibello AM, Eichler RAS, Reckziegel P, Da Silva RNO, Dos Santos NB, Camara NOS, Castoldi A, Barreto-Chaves MLM, Dale CS, Senger N, Lima JDCC, Seelaender MCL, Inada AC, Akamine EH, Castro LM, Rodrigues AC, Neto JCR, Ferro ES. The Relevance of Thimet Oligopeptidase in the Regulation of Energy Metabolism and Diet-Induced Obesity. Biomolecules 2020; 10:E321. [PMID: 32079362 DOI: 10.3390/biom10020321] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 02/10/2020] [Accepted: 02/12/2020] [Indexed: 12/11/2022] Open
Abstract
Thimet oligopeptidase (EC 3.4.24.15; EP24.15; THOP1) is a potential therapeutic target, as it plays key biological functions in processing biologically functional peptides. The structural conformation of THOP1 provides a unique restriction regarding substrate size, in that it only hydrolyzes peptides (optimally, those ranging from eight to 12 amino acids) and not proteins. The proteasome activity of hydrolyzing proteins releases a large number of intracellular peptides, providing THOP1 substrates within cells. The present study aimed to investigate the possible function of THOP1 in the development of diet-induced obesity (DIO) and insulin resistance by utilizing a murine model of hyperlipidic DIO with both C57BL6 wild-type (WT) and THOP1 null (THOP1−/−) mice. After 24 weeks of being fed a hyperlipidic diet (HD), THOP1−/− and WT mice ingested similar chow and calories; however, the THOP1−/− mice gained 75% less body weight and showed neither insulin resistance nor non-alcoholic fatty liver steatosis when compared to WT mice. THOP1−/− mice had increased adrenergic-stimulated adipose tissue lipolysis as well as a balanced level of expression of genes and microRNAs associated with energy metabolism, adipogenesis, or inflammation. Altogether, these differences converge to a healthy phenotype of THOP1−/− fed a HD. The molecular mechanism that links THOP1 to energy metabolism is suggested herein to involve intracellular peptides, of which the relative levels were identified to change in the adipose tissue of WT and THOP1−/− mice. Intracellular peptides were observed by molecular modeling to interact with both pre-miR-143 and pre-miR-222, suggesting a possible novel regulatory mechanism for gene expression. Therefore, we successfully demonstrated the previously anticipated relevance of THOP1 in energy metabolism regulation. It was suggested that intracellular peptides were responsible for mediating the phenotypic differences that are described herein by a yet unknown mechanism of action.
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Wagner L, Björkqvist M, Lundh SH, Wolf R, Börgel A, Schlenzig D, Ludwig HH, Rahfeld JU, Leavitt B, Demuth HU, Petersén Å, von Hörsten S. Neuropeptide Y (NPY) in cerebrospinal fluid from patients with Huntington's Disease: increased NPY levels and differential degradation of the NPY1-30
fragment. J Neurochem 2016; 137:820-37. [DOI: 10.1111/jnc.13624] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 03/17/2016] [Accepted: 03/20/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Leona Wagner
- Deutschsprachige Selbsthilfegruppe für Alkaptonurie (DSAKU) e.V.; Stuttgart Germany
- Probiodrug AG; Halle (Saale) Germany
- Department of Experimental Therapy; Franz-Penzoldt-Center; Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
| | - Maria Björkqvist
- Brain Disease Biomarker Unit; Department of Experimental Medical Science; Wallenberg Neuroscience Centre; Lund University; Lund Sweden
| | - Sofia Hult Lundh
- Translational Neuroendocrine Research Unit; Lund University; Lund Sweden
| | - Raik Wolf
- Probiodrug AG; Halle (Saale) Germany
- Center for Clinical Chemistry, Microbiology and Transfusion; Klinikum St. Georg GmbH; Leipzig Germany
| | - Arne Börgel
- Probiodrug AG; Halle (Saale) Germany
- Institute of Molecular Biology (IMB); Johannes Gutenberg-University Mainz; Mainz Germany
| | - Dagmar Schlenzig
- Department of Drug Design and Target Validation; Fraunhofer-Institute for Cell Therapy and Immunology; Halle (Saale) Germany
| | | | - Jens-Ulrich Rahfeld
- Department of Drug Design and Target Validation; Fraunhofer-Institute for Cell Therapy and Immunology; Halle (Saale) Germany
| | - Blair Leavitt
- The Centre for Molecular Medicine and Therapeutics Child and Family Research Institute; BC Children's Hospital; The University of British Columbia; Vancouver British Columbia
| | - Hans-Ulrich Demuth
- Department of Drug Design and Target Validation; Fraunhofer-Institute for Cell Therapy and Immunology; Halle (Saale) Germany
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit; Lund University; Lund Sweden
| | - Stephan von Hörsten
- Department of Experimental Therapy; Franz-Penzoldt-Center; Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
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6
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Bruce LA, Cyr NE, Qiao JW, DeFries CC, Tetel MJ, Wolfson AJ. Neuropeptidase activity is down-regulated by estradiol in steroid-sensitive regions of the hypothalamus in female mice. Neuropeptides 2012; 46:167-72. [PMID: 22672888 PMCID: PMC3404208 DOI: 10.1016/j.npep.2012.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 03/26/2012] [Accepted: 04/24/2012] [Indexed: 11/16/2022]
Abstract
Thimet oligopeptidase (TOP) and prolyl endopeptidase (PEP) are neuropeptidases involved in the hydrolysis of gonadotropin-releasing hormone, a key component of the hypothalamic-pituitary-gonadal axis. GnRH is regulated in part by feedback from steroid hormones such as estradiol. Previously, we demonstrated that TOP levels are down-regulated by estradiol in reproductively-relevant regions of the female rodent brain. The present study supports these findings by showing that TOP enzyme activity, as well as protein levels, in the ventromedial hypothalamic nucleus of female mice is controlled by estradiol. We further demonstrate that PEP levels in this same brain region are down-regulated by estradiol in parallel with those of TOP. These findings provide evidence that these neuropeptidases are part of the fine control of hormone levels in the HPG axis.
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Affiliation(s)
- Lisa A. Bruce
- Chemistry Department, Wellesley College, Wellesley, MA. USA
| | - Nicole E. Cyr
- Chemistry Department, Wellesley College, Wellesley, MA. USA
| | - Jana W. Qiao
- Chemistry Department, Wellesley College, Wellesley, MA. USA
| | | | - Marc J. Tetel
- Neuroscience Program, Wellesley College, Wellesley, MA. USA
| | - Adele J. Wolfson
- Chemistry Department, Wellesley College, Wellesley, MA. USA
- Corresponding author: Chemistry Department, Wellesley College, 106 Central St., Wellesley, MA 01746 USA; 781-283-3106 (tel); 781-283-3642 (fax);
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Sbardella D, Fasciglione GF, Gioia M, Ciaccio C, Tundo GR, Marini S, Coletta M. Human matrix metalloproteinases: an ubiquitarian class of enzymes involved in several pathological processes. Mol Aspects Med 2012; 33:119-208. [PMID: 22100792 DOI: 10.1016/j.mam.2011.10.015] [Citation(s) in RCA: 164] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 10/29/2011] [Indexed: 02/07/2023]
Abstract
Human matrix metalloproteinases (MMPs) belong to the M10 family of the MA clan of endopeptidases. They are ubiquitarian enzymes, structurally characterized by an active site where a Zn(2+) atom, coordinated by three histidines, plays the catalytic role, assisted by a glutamic acid as a general base. Various MMPs display different domain composition, which is very important for macromolecular substrates recognition. Substrate specificity is very different among MMPs, being often associated to their cellular compartmentalization and/or cellular type where they are expressed. An extensive review of the different MMPs structural and functional features is integrated with their pathological role in several types of diseases, spanning from cancer to cardiovascular diseases and to neurodegeneration. It emerges a very complex and crucial role played by these enzymes in many physiological and pathological processes.
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Wangler NJ, Santos KL, Schadock I, Hagen FK, Escher E, Bader M, Speth RC, Karamyan VT. Identification of membrane-bound variant of metalloendopeptidase neurolysin (EC 3.4.24.16) as the non-angiotensin type 1 (non-AT1), non-AT2 angiotensin binding site. J Biol Chem 2011; 287:114-122. [PMID: 22039052 DOI: 10.1074/jbc.m111.273052] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recently, we discovered a novel non-angiotensin type 1 (non-AT1), non-AT2 angiotensin binding site in rodent and human brain membranes, which is distinctly different from angiotensin receptors and key proteases processing angiotensins. It is hypothesized to be a new member of the renin-angiotensin system. This study was designed to isolate and identify this novel angiotensin binding site. An angiotensin analog, photoaffinity probe 125I-SBpa-Ang II, was used to specifically label the non-AT1, non-AT2 angiotensin binding site in mouse forebrain membranes, followed by a two-step purification procedure based on the molecular size and isoelectric point of the photoradiolabeled binding protein. Purified samples were subjected to two-dimensional gel electrophoresis followed by mass spectrometry identification of proteins in the two-dimensional gel sections containing radioactivity. LC-MS/MS analysis revealed eight protein candidates, of which the four most abundant were immunoprecipitated after photoradiolabeling. Immunoprecipitation studies indicated that the angiotensin binding site might be the membrane-bound variant of metalloendopeptidase neurolysin (EC 3.4.24.16). To verify these observations, radioligand binding and photoradiolabeling experiments were conducted in membrane preparations of HEK293 cells overexpressing mouse neurolysin or thimet oligopeptidase (EC 3.4.24.15), a closely related metalloendopeptidase of the same family. These experiments also identified neurolysin as the non-AT1, non-AT2 angiotensin binding site. Finally, brain membranes of mice lacking neurolysin were nearly devoid of the non-AT1, non-AT2 angiotensin binding site, further establishing membrane-bound neurolysin as the binding site. Future studies will focus on the functional significance of this highly specific, high affinity interaction between neurolysin and angiotensins.
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Affiliation(s)
- Naomi J Wangler
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, Texas, 79106
| | - Kira L Santos
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida 33328
| | - Ines Schadock
- Max-Delbrück-Center for Molecular Medicine, Berlin 13092, Germany
| | - Fred K Hagen
- Proteomics Center, Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York 14642
| | - Emanuel Escher
- Department of Pharmacology, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4, Canada
| | - Michael Bader
- Max-Delbrück-Center for Molecular Medicine, Berlin 13092, Germany
| | - Robert C Speth
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida 33328; Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, Florida 32611
| | - Vardan T Karamyan
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, Texas, 79106; Vascular Drug Research Center, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, Texas 79106.
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Van Dorpe S, Adriaens A, Polis I, Peremans K, Van Bocxlaer J, De Spiegeleer B. Analytical characterization and comparison of the blood-brain barrier permeability of eight opioid peptides. Peptides 2010; 31:1390-9. [PMID: 20347901 DOI: 10.1016/j.peptides.2010.03.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/20/2010] [Accepted: 03/22/2010] [Indexed: 12/31/2022]
Abstract
Opioid drugs, including the newly developed peptides, should penetrate the blood-brain barrier (BBB) for pain management activity. Although BBB transport is fragmentarily described for some mu-opioid peptides, a complete and comparative overview is currently lacking. In this study, the BBB transport of eight opioid peptides (EM-1, EM-2, CTAP, CTOP, DAMGO, dermorphin, TAPP and TAPS) is described and compared. In addition, the metabolic stability in plasma and brain was evaluated. The highest influx rate was obtained for dermorphin (K(in)=2.18 microl/(g x min)), followed by smaller rates for EM-1, EM-2 and TAPP (K(in)=1.06-1.14 microl/(g x min)). Negligible influx was observed for DAMGO, CTOP and TAPS (K(in)=0.18-0.40 microl/(g x min)) and no influx for CTAP. Capillary depletion revealed that all peptides reached brain parenchyma for over 75%. Efflux was shown for TAPP (t(1/2)=2.82 min) and to a lesser extent for EM-1, EM-2 and DAMGO (t(1/2)=10.66-21.98 min), while no significant efflux was observed for the other peptides. All peptides were stable in mouse plasma and brain, with generally higher stability in brain, except for EM-1 and EM-2 which showed plasma half-life stabilities of a few minutes only.
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Affiliation(s)
- Sylvia Van Dorpe
- Drug Quality and Registration (DruQuaR) Group, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
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Gelman JS, Fricker LD. Hemopressin and other bioactive peptides from cytosolic proteins: are these non-classical neuropeptides? AAPS J 2010; 12:279-89. [PMID: 20383670 DOI: 10.1208/s12248-010-9186-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 03/22/2010] [Indexed: 12/31/2022]
Abstract
Peptides perform many roles in cell-cell signaling; examples include neuropeptides, hormones, and growth factors. Although the vast majority of known neuropeptides are produced in the secretory pathway, a number of bioactive peptides are derived from cytosolic proteins. For example, the hemopressins are a family of peptides derived from alpha and beta hemoglobin which bind to the CB1 cannabinoid receptor, functioning as agonists or antagonists/inverse agonists depending on the size of the peptide. However, the finding that peptides derived from cytosolic proteins can affect receptors does not prove that these peptides are true endogenous signaling molecules. In order for the hemopressins and other peptides derived from cytosolic proteins to be considered neuropeptide-like signaling molecules, they must be synthesized in brain, they must be secreted in levels sufficient to produce effects, and either their synthesis or secretion should be regulated. If these criteria are met, we propose the name "non-classical neuropeptide" for this category of cytosolic bioactive peptide. This would be analogous to the non-classical neurotransmitters, such as nitric oxide and anandamide, which are not stored in secretory vesicles and released upon stimulation but are synthesized upon stimulation and constitutively released. We review some examples of cytosolic peptides from various protein precursors, describe potential mechanisms of their biosynthesis and secretion, and discuss the possibility that these peptides are signaling molecules in the brain, focusing on the criteria that these peptides would have to fill in order to be considered non-classical neuropeptides.
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Affiliation(s)
- Julia S Gelman
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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11
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Russo LC, Goñi CN, Castro LM, Asega AF, Camargo ACM, Trujillo CA, Ulrich H, Glucksman MJ, Scavone C, Ferro ES. Interaction with calmodulin is important for the secretion of thimet oligopeptidase following stimulation. FEBS J 2009; 276:4358-71. [PMID: 19614740 DOI: 10.1111/j.1742-4658.2009.07144.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Thimet oligopeptidase (EC 3.4.24.15; EP24.15) was originally described as a neuropeptide-metabolizing enzyme, highly expressed in the brain, kidneys and neuroendocrine tissue. EP24.15 lacks a typical signal peptide sequence for entry into the secretory pathway and is secreted by cells via an unconventional and unknown mechanism. In this study, we identified a novel calcium-dependent interaction between EP24.15 and calmodulin, which is important for the stimulated, but not constitutive, secretion of EP24.15. We demonstrated that, in vitro, EP24.15 and calmodulin physically interact only in the presence of Ca2+, with an estimated Kd value of 0.52 mum. Confocal microscopy confirmed that EP24.15 colocalizes with calmodulin in the cytosol of resting HEK293 cells. This colocalization markedly increases when cells are treated with either the calcium ionophore A23187 or the protein kinase A activator forskolin. Overexpression of calmodulin in HEK293 cells is sufficient to greatly increase the A23187-stimulated secretion of EP24.15, which can be inhibited by the calmodulin inhibitor calmidazolium. The specific inhibition of protein kinase A with KT5720 reduces the A23187-stimulated secretion of EP24.15 and inhibits the synergistic effects of forskolin with A23187. Treatment with calmidazolium and KT5720 nearly abolishes the stimulatory effects of A23187 on EP24.15 secretion. Together, these data suggest that the interaction between EP24.15 and calmodulin is regulated within cells and is important for the stimulated secretion of EP24.15 from HEK293 cells.
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Affiliation(s)
- Lilian C Russo
- Department of Cell Biology and Development, Institute of Biomedical Sciences, University of São Paulo, Brazil
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12
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Abstract
PURPOSE This paper deals with the capability of the ciliary epithelium to express neurolysin, involved in the inactivation of numerous neuropeptides. METHODS Total RNAs from ciliary body (CB) were processed for RT-PCR, and the amplification products were sequenced. The whole-protein extracts of CBs were analyzed using the Western blot. The CBs were processed for neurolysin immunolocalization. RESULTS The RT-PCR detected the presence of neurolysin mRNA in the ciliary body. The Western blot assays demonstrated immunochemical cross-reactivity with neurolysin. The immunoreactivity to neurolysin was observed in ciliary epithelium. CONCLUSIONS These results indicate that the ciliary epithelium expresses neurolysin.
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Affiliation(s)
- Rubens Bertazolli-Filho
- Departamento de Biologia Celular e Molecular e Bioagentes Patogêcos, Faculdade de Medicina de Ribeirão Preto/USP, 14049-900 Ribeirão Preto, SP, Brazil.
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Gomes I, Grushko JS, Golebiewska U, Hoogendoorn S, Gupta A, Heimann AS, Ferro ES, Scarlata S, Fricker LD, Devi LA. Novel endogenous peptide agonists of cannabinoid receptors. FASEB J 2009; 23:3020-9. [PMID: 19380512 DOI: 10.1096/fj.09-132142] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Hemopressin (Hp), a 9-residue alpha-hemoglobin-derived peptide, was previously reported to function as a CB(1) cannabinoid receptor antagonist (1) . In this study, we report that mass spectrometry (MS) data from peptidomics analyses of mouse brain extracts identified N-terminally extended forms of Hp containing either three (RVD-Hpalpha) or two (VD-Hpalpha) additional amino acids, as well as a beta-hemoglobin-derived peptide with sequence similarity to that of hemopressin (VD-Hpbeta). Characterization of the alpha-hemoglobin-derived peptides using binding and functional assays shows that in contrast to Hp, which functions as a CB(1) cannabinoid receptor antagonist, both RVD-Hpalpha and VD-Hpalpha function as agonists. Studies examining the increase in the phosphorylation of ERK1/2 levels or release of intracellular Ca(2+) indicate that these peptides activate a signal transduction pathway distinct from that activated by the endocannabinoid, 2-arachidonoylglycerol, or the classic CB(1) agonist, Hu-210. This finding suggests an additional mode of regulation of endogenous cannabinoid receptor activity. Taken together, these results suggest that the CB(1) receptor is involved in the integration of signals from both lipid- and peptide-derived signaling molecules.
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Affiliation(s)
- Ivone Gomes
- Department of Pharmacology and Systems Therapeutics, Mt. Sinai School of Medicine, New York, NY 10029, USA
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Abstract
Gonadotrophin-releasing hormone (GnRH) was first isolated in the mammal and shown to be the primary regulator of the reproductive system through its initiation of pituitary gonadotrophin release. Subsequent to its discovery, this form of GnRH has been shown to be one of many structural variants found in the brain and peripheral tissues. Accordingly, the original form first discovered and cloned in the mammal is commonly referred to as GnRH-I. In addition to the complex regulation of GnRH-I synthesis, release and function, further evidence suggests that the processing of GnRH-I produces yet another layer of complexity in its activity. GnRH-I is processed by a zinc metalloendopeptidase EC 3.4.24.15 (EP24.15), which cleaves the hormone at the covalent bond between the fifth and sixth residue of the decapeptide (Tyr(5)-Gly(6)) to form GnRH-(1-5). It was previously thought that the cleavage of GnRH-I by EP24.15 represents the initiation of its degradation. Here, we review the evidence for the involvement of GnRH-(1-5), the metabolite of GnRH-I, in the regulation of GnRH-I synthesis, secretion and facilitation of reproductive behaviour.
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Affiliation(s)
- T John Wu
- Program in Neuroscience, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
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15
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Pollio G, Hoozemans JJM, Andersen CA, Roncarati R, Rosi MC, van Haastert ES, Seredenina T, Diamanti D, Gotta S, Fiorentini A, Magnoni L, Raggiaschi R, Rozemuller AJM, Casamenti F, Caricasole A, Terstappen GC. Increased expression of the oligopeptidase THOP1 is a neuroprotective response to Abeta toxicity. Neurobiol Dis 2008; 31:145-58. [PMID: 18571100 DOI: 10.1016/j.nbd.2008.04.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 04/03/2008] [Accepted: 04/17/2008] [Indexed: 01/18/2023] Open
Abstract
In a comprehensive proteomics study aiming at the identification of proteins associated with amyloid-beta (Abeta)-mediated toxicity in cultured cortical neurons, we have identified Thimet oligopeptidase (THOP1). Functional modulation of THOP1 levels in primary cortical neurons demonstrated that its overexpression was neuroprotective against Abeta toxicity, while RNAi knockdown made neurons more vulnerable to amyloid peptide. In the TgCRND8 transgenic mouse model of amyloid plaque deposition, an age-dependent increase of THOP1 expression was found in brain tissue, where it co-localized with Abeta plaques. In accordance with these findings, THOP1 expression was significantly increased in human AD brain tissue as compared to non-demented controls. These results provide compelling evidence for a neuroprotective role of THOP1 against toxic effects of Abeta in the early stages of AD pathology, and suggest that the observed increase in THOP1 expression might be part of a compensatory defense mechanism of the brain against an increased Abeta load.
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Affiliation(s)
- Giuseppe Pollio
- Siena Biotech SpA, Discovery Research, Via Fiorentina 1, 53100 Siena, Italy
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16
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Walters K, Wegorzewska IN, Chin Y, Parikh MG, Wu TJ. Luteinizing Hormone-Releasing Hormone I (LHRH-I) and Its Metabolite in Peripheral Tissues. Exp Biol Med (Maywood) 2008; 233:123-30. [DOI: 10.3181/0707-mr-201] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Luteinizing hormone-releasing hormone (LHRH) was first isolated in the mammalian hypothalamus and shown to be the primary regulator of the reproductive system through its initiation of pituitary gonadotropin release. Since its discovery, this form of LHRH (LHRH-I) has been shown to be one of many structural variants with a variety of roles in both the brain and peripheral tissues. Enormous interest has been focused on LHRH-I and LHRH-II and their cognate receptors as targets for designing therapies to treat cancers of the reproductive system. LHRH-I is processed by a zinc metalloendopeptidase EC 3.4.24.15 (EP24.15) that cleaves the hormone at the fifth and sixth bond of the decapeptide (Tyr5-Gly6) to form LHRH-( 1 – 5 ). We have previously reported that the autoregulation of LHRH gene expression can also be mediated by its processed peptide, LHRH-( 1 – 5 ). Furthermore, LHRH-( 1 – 5 ) has also been shown to be involved in cell proliferation. This review will focus on the possible roles of LHRH and its processed peptide, LHRH-( 1 – 5 ), in non-hypothalamic tissues.
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17
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Karamyan VT, Speth RC. Enzymatic pathways of the brain renin-angiotensin system: unsolved problems and continuing challenges. ACTA ACUST UNITED AC 2007; 143:15-27. [PMID: 17493693 PMCID: PMC7114358 DOI: 10.1016/j.regpep.2007.03.006] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Revised: 03/18/2007] [Accepted: 03/19/2007] [Indexed: 11/28/2022]
Abstract
The brain renin-angiotensin system continues to be enigmatic more than 40 years after the brain was first recognized to be a site of action of angiotensin II. This review focuses on the enzymatic pathways for the formation and degradation of the growing number of active angiotensins in the brain. A brief description and nomenclature of the peptidases involved in the processing of angiotensin peptides in the brain is given. Of primary interest is the array of enzymes that degrade radiolabeled angiotensins in receptor binding assays. This poses major challenges to studies of brain angiotensin receptors and it is debatable whether an accurate determination of brain angiotensin receptor binding kinetics has yet been made. The quandary facing the investigator of brain angiotensin receptors is the need to protect the radioligand from metabolic alteration while maintaining the characteristics of the receptors in situ. It is the tenet of this review that we have yet to fully understand the binding characteristics of brain angiotensin receptors and the extent of their distribution in the brain because of our inability to fully protect the angiotensins from metabolic alteration until equilibrium binding conditions can be attained.
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Affiliation(s)
- Vardan T Karamyan
- Department of Pharmacology and Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, United States
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18
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Lim EJ, Sampath S, Coll-Rodriguez J, Schmidt J, Ray K, Rodgers DW. Swapping the Substrate Specificities of the Neuropeptidases Neurolysin and Thimet Oligopeptidase. J Biol Chem 2007; 282:9722-9732. [PMID: 17251185 DOI: 10.1074/jbc.m609897200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thimet oligopeptidase (EC 3.4.24.15) and neurolysin (EC 3.4.24.16) are closely related zinc-dependent metallopeptidases that metabolize small bioactive peptides. They cleave many substrates at the same sites, but they recognize different positions on others, including neurotensin, a 13-residue peptide involved in modulation of dopaminergic circuits, pain perception, and thermoregulation. On the basis of crystal structures and previous mapping studies, four sites (Glu-469/Arg-470, Met-490/Arg-491, His-495/Asn-496, and Arg-498/Thr-499; thimet oligopeptidase residues listed first) in their substrate-binding channels appear positioned to account for differences in specificity. Thimet oligopeptidase mutated so that neurolysin residues are at all four positions cleaves neurotensin at the neurolysin site, and the reverse mutations in neurolysin switch hydrolysis to the thimet oligopeptidase site. Using a series of constructs mutated at just three of the sites, it was determined that mutations at only two (Glu-469/Arg-470 and Arg-498/Thr-499) are required to swap specificity, a result that was confirmed by testing the two-mutant constructs. If only either one of the two sites is mutated in thimet oligopeptidase, then the enzyme cleaves almost equally at the two hydrolysis positions. Crystal structures of both two-mutant constructs show that the mutations do not perturb local structure, but side chain conformations at the Arg-498/Thr-499 position differ from those of the mimicked enzyme. A model for differential recognition of neurotensin based on differences in surface charge distribution in the substrate binding sites is proposed. The model is supported by the finding that reducing the positive charge on the peptide results in cleavage at both hydrolysis sites.
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Affiliation(s)
- Eun Jeong Lim
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536
| | - Sowmya Sampath
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536
| | - Jerry Coll-Rodriguez
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536
| | - Jack Schmidt
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536
| | - Kallol Ray
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536
| | - David W Rodgers
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536.
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Karamyan VT, Speth RC. Identification of a novel non-AT1, non-AT2 angiotensin binding site in the rat brain. Brain Res 2007; 1143:83-91. [PMID: 17306233 DOI: 10.1016/j.brainres.2007.01.051] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 01/09/2007] [Accepted: 01/18/2007] [Indexed: 11/24/2022]
Abstract
Efforts to protect radiolabeled angiotensins from metabolism during receptor binding assays date back more than 30 years. However, this continues to be a problem. This study focused on the effects of a protease inhibitor, p-chloromercuribenzoate (PCMB), on the binding of (125)I-Ang II to rat brain membranes. Addition of PCMB to the incubation medium revealed a high affinity binding site for (125)I-Ang II in brain membranes (K(d)=1-4 nM) with a greater amount of binding than revealed in previous studies of brain Ang II receptors. Further characterization of this binding, revealed it to be insensitive to inhibition by losartan (an AT(1) receptor antagonist) and PD123319 (an AT(2) receptor antagonist). This non-AT1, non-AT2 binding site was not present in liver or adrenal membranes. It was activated by a limited range of concentrations of PCMB, with maximal activation at 0.3-1 mM. This binding site was equally abundant in cerebral cortex (a brain region with few Ang II receptors) and the hypothalamus (a brain region with abundant Ang II receptors). The binding site was also present in mouse brain, but not mouse liver. The binding site shows high affinity for Ang I, Ang II and Ang III (K(i) approximately 40-100 nM), but lesser affinity for smaller angiotensin fragments and other neuropeptides. This binding site shares some characteristics with the liver cytosolic Ang II binding proteins, later identified as endopeptidases EC 3.4.24.15 and/or EC 3.4.24.16. However, some unique characteristics of this non-AT1, non-AT2 binding site suggest that it may be a novel angiotensin binding substance.
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Affiliation(s)
- Vardan T Karamyan
- Department of Pharmacology and Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
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20
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Abstract
Endopeptidase 24.15 (ep24.15: EC3.4.24.15), a secreted protein involved in peptide metabolism, is unusual in that it does not contain a signal peptide sequence. In this work, we describe the physical interaction between ep24.15 and 14-3-3 epsilon, one isoform of a family of ubiquitous phosphoserine/threonine-scaffold proteins that organizes cell signaling and is involved in exocytosis. The interaction between ep24.15 and 14-3-3 epsilon increased following phosphorylation of ep24.15 at Ser(644) by protein kinase A (PKA). The co-localization of ep24.15 and 14-3-3 epsilon was increased by exposure of HEK293 cells (human embryonic kidney cells) to forskolin (10 microm). Overexpression of 14-3-3 epsilon in HEK293 cells almost doubled the secretion of ep24.15 stimulated by A23187 (7.5 microm) from 10%[1.4 +/- 0.24 AFU/(min 10(6) cells)] to 19%[2.54 +/- 0.24 AFU/(min 10(6) cells)] (p < 0.001) of the total intracellular enzyme activity. Treatment with forskolin had a synergistic effect on the A23187-stimulated secretion of ep24.15 that was totally blocked by the PKA inhibitor KT5720. The ep24.15 point mutation S644A reduced the co-localization of ep24.15 and 14-3-3 in stably transfected HEK293 cells. Indeed, secretion of the ep24.15 S644A mutant from these cells was only slightly stimulated by A23187 and insensitive to forskolin, in contrast to that of the wild type enzyme. Together, these data suggest that prior interaction with 14-3-3 is an important step in the unconventional stimulated secretion of ep24.15.
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Affiliation(s)
- Flávia R Carreño
- Department of Cell Biology and Development, Cell Biology Program, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
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