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Shikhkerimov RK, Istomina EV. Recombinant botulinum toxin as a new stage in the development of botulinum toxin therapy. Possibilities and perspectives of use in neurological practice. NEUROLOGY, NEUROPSYCHIATRY, PSYCHOSOMATICS 2022. [DOI: 10.14412/2074-2711-2022-6-103-109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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2
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Lalaurie CJ, Splevins A, Barata TS, Bunting KA, Higazi DR, Zloh M, Spiteri VA, Perkins SJ, Dalby PA. Elucidation of critical pH-dependent structural changes in Botulinum Neurotoxin E. J Struct Biol 2022; 214:107876. [PMID: 35738335 DOI: 10.1016/j.jsb.2022.107876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/13/2022] [Accepted: 06/16/2022] [Indexed: 10/18/2022]
Abstract
Botulinum Neurotoxins (BoNT) are the most potent toxins currently known. However, they also have therapeutic applications for an increasing number of motor related conditions due to their specificity, and low diffusion into the system. Although the start- and end- points for the BoNT mechanism of action are well-studied, a critical step remains poorly understood. It is theorised that BoNTs undergo a pH-triggered conformational shift, activating the neurotoxin by priming it to form a transmembrane (TM) channel. To test this hypothesis, we combined molecular dynamics (MD) simulations and small-angle x-ray scattering (SAXS), revealing a new conformation of serotype E (BoNT/E). This conformation was exclusively observed in simulations below pH 5.5, as determined by principal component analysis (PCA), and its theoretical SAXS profile matched an experimental SAXS profile obtained at pH 4. Additionally, a localised secondary structural change was observed in MD simulations below pH 5.5, in a region previously identified as instrumental for membrane insertion for serotype A (BoNT/A). These changes were found at a critical pH value for BoNTs in vivo, and may be relevant for their therapeutic use.
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Affiliation(s)
- Christophe J Lalaurie
- Department of Biochemical Engineering, Bernard Katz Building, University College London, Gordon Street, London WC1H 0AH, UK
| | - Andrew Splevins
- Evox Therapeutics Ltd, Oxford Science Park, Medwar Center, Oxford, England OX4 4HG, UK; Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY UK
| | - Teresa S Barata
- FairJourney Biologics, 823 Rua do Campo Alegre, Porto, Porto 4150-180, Portugal; Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY UK
| | - Karen A Bunting
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY UK
| | - Daniel R Higazi
- Ipsen Biopharm Ltd., Wrexham Industrial Estate, 9 Ash Road, LL13 9UF, UK
| | - Mire Zloh
- UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Valentina A Spiteri
- Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, UK
| | - Stephen J Perkins
- Department of Structural and Molecular Biology, Division of Biosciences, Darwin Building, University College London, Gower Street, London WC1E 6BT, UK
| | - Paul A Dalby
- Department of Biochemical Engineering, Bernard Katz Building, University College London, Gordon Street, London WC1H 0AH, UK.
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3
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Belinskaia M, Zurawski T, Kaza SK, Antoniazzi C, Dolly JO, Lawrence GW. NGF Enhances CGRP Release Evoked by Capsaicin from Rat Trigeminal Neurons: Differential Inhibition by SNAP-25-Cleaving Proteases. Int J Mol Sci 2022; 23:ijms23020892. [PMID: 35055082 PMCID: PMC8778182 DOI: 10.3390/ijms23020892] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/08/2022] [Accepted: 01/11/2022] [Indexed: 11/23/2022] Open
Abstract
Nerve growth factor (NGF) is known to intensify pain in various ways, so perturbing pertinent effects without negating its essential influences on neuronal functions could help the search for much-needed analgesics. Towards this goal, cultured neurons from neonatal rat trigeminal ganglia—a locus for craniofacial sensory nerves—were used to examine how NGF affects the Ca2+-dependent release of a pain mediator, calcitonin gene-related peptide (CGRP), that is triggered by activating a key signal transducer, transient receptor potential vanilloid 1 (TRPV1) with capsaicin (CAP). Measurements utilised neurons fed with or deprived of NGF for 2 days. Acute re-introduction of NGF induced Ca2+-dependent CGRP exocytosis that was inhibited by botulinum neurotoxin type A (BoNT/A) or a chimera of/E and/A (/EA), which truncated SNAP-25 (synaptosomal-associated protein with Mr = 25 k) at distinct sites. NGF additionally caused a Ca2+-independent enhancement of the neuropeptide release evoked by low concentrations (<100 nM) of CAP, but only marginally increased the peak response to ≥100 nM. Notably, BoNT/A inhibited CGRP exocytosis evoked by low but not high CAP concentrations, whereas/EA effectively reduced responses up to 1 µM CAP and inhibited to a greater extent its enhancement by NGF. In addition to establishing that sensitisation of sensory neurons to CAP by NGF is dependent on SNARE-mediated membrane fusion, insights were gleaned into the differential ability of two regions in the C-terminus of SNAP-25 (181–197 and 198–206) to support CAP-evoked Ca2+-dependent exocytosis at different intensities of stimulation.
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4
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Rosales RL, Cuffe L, Regnault B, Trosch RM. Pain in cervical dystonia: mechanisms, assessment and treatment. Expert Rev Neurother 2021; 21:1125-1134. [PMID: 34569398 DOI: 10.1080/14737175.2021.1984230] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
INTRODUCTION In patients with cervical dystonia (CD), pain is a major contributor to disability and social isolation and is often the main reason patients seek treatment. Surveys evaluating patient perceptions of their CD symptoms consistently highlight pain as a troublesome and disabling feature of their condition with significant impact on daily life and work. AREAS COVERED In this article, the authors review the epidemiology, assessment, possible mechanisms and treatment of pain in CD, including a meta-analysis of randomized controlled trial data with abobotulinumtoxinA. EXPERT OPINION Mechanisms of pain in CD may be muscle-based and non-muscle based. Accumulating evidence suggests that non-muscle-based mechanisms (such as abnormal transmission and processing of nociceptive stimuli, dysfunction of descending pain inhibitory pathways as well as structural and network changes in the basal ganglia, cortex and other areas) may also contribute to pain in CD alongside prolonged muscle contraction. Chemodenervation with botulinum toxin is considered the first-line treatment for CD. Treatment with botulinum toxin is usually effective, but optimization of the injection parameters should include consideration of pain as a core symptom in addition to the motor problems.
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Affiliation(s)
- Raymond L Rosales
- Dept. of Neurology and Psychiatry, the Neuroscience Institute, University of Santo Tomas Hospital, Manila, Philippines.,The Institute for Neurosciences, St. Luke's Medical Center, Quezon City, Philippines
| | | | | | - Richard M Trosch
- The Parkinson's and Movement Disorders Center, Farmington Hills, MI, USA
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5
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Blum TR, Liu H, Packer MS, Xiong X, Lee PG, Zhang S, Richter M, Minasov G, Satchell KJF, Dong M, Liu DR. Phage-assisted evolution of botulinum neurotoxin proteases with reprogrammed specificity. Science 2021; 371:803-810. [PMID: 33602850 DOI: 10.1126/science.abf5972] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 12/24/2020] [Indexed: 12/14/2022]
Abstract
Although bespoke, sequence-specific proteases have the potential to advance biotechnology and medicine, generation of proteases with tailor-made cleavage specificities remains a major challenge. We developed a phage-assisted protease evolution system with simultaneous positive and negative selection and applied it to three botulinum neurotoxin (BoNT) light-chain proteases. We evolved BoNT/X protease into separate variants that preferentially cleave vesicle-associated membrane protein 4 (VAMP4) and Ykt6, evolved BoNT/F protease to selectively cleave the non-native substrate VAMP7, and evolved BoNT/E protease to cleave phosphatase and tensin homolog (PTEN) but not any natural BoNT protease substrate in neurons. The evolved proteases display large changes in specificity (218- to >11,000,000-fold) and can retain their ability to form holotoxins that self-deliver into primary neurons. These findings establish a versatile platform for reprogramming proteases to selectively cleave new targets of therapeutic interest.
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Affiliation(s)
- Travis R Blum
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.,Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Hao Liu
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Michael S Packer
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.,Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Xiaozhe Xiong
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Pyung-Gang Lee
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Sicai Zhang
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Michelle Richter
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.,Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA. .,Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA. .,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.,Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
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Sikorra S, Donald S, Elliott M, Schwede S, Coker SF, Kupinski AP, Tripathi V, Foster K, Beard M, Binz T. Engineering an Effective Human SNAP-23 Cleaving Botulinum Neurotoxin A Variant. Toxins (Basel) 2020; 12:toxins12120804. [PMID: 33352834 PMCID: PMC7766560 DOI: 10.3390/toxins12120804] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/11/2020] [Accepted: 12/13/2020] [Indexed: 12/13/2022] Open
Abstract
Botulinum neurotoxin (BoNT) serotype A inhibits neurotransmitter release by cleaving SNAP-25 and represents an established pharmaceutical for treating medical conditions caused by hyperactivity of cholinergic nerves. Oversecretion from non-neuronal cells is often also the cause of diseases. Notably, excessive release of inflammatory messengers is thought to contribute to diseases such as chronic obstructive pulmonary disease, asthma, diabetes etc. The expansion of its application to these medical conditions is prevented because the major non-neuronal SNAP-25 isoform responsible for exocytosis, SNAP-23, is, in humans, virtually resistant to BoNT/A. Based on previous structural data and mutagenesis studies of SNAP-23 we optimized substrate binding pockets of the enzymatic domain for interaction with SNAP-23. Systematic mutagenesis and rational design yielded the mutations E148Y, K166F, S254A, and G305D, each of which individually increased the activity of LC/A against SNAP-23 between 3- to 23-fold. The assembled quadruple mutant showed approximately 2000-fold increased catalytic activity against human SNAP-23 in in vitro cleavage assays. A comparable increase in activity was recorded for the full-length BoNT/A quadruple mutant tested in cultivated primary neurons transduced with a fluorescently tagged-SNAP-23 encoding gene. Equipped with a suitable targeting domain this quadruple mutant promises to complete successfully tests in cells of the immune system.
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Affiliation(s)
- Stefan Sikorra
- Institut für Zellbiochemie, OE 4310, Medizinische Hochschule Hannover, 30623 Hannover, Germany; (S.S.); (S.S.)
| | - Sarah Donald
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
| | - Mark Elliott
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
| | - Susan Schwede
- Institut für Zellbiochemie, OE 4310, Medizinische Hochschule Hannover, 30623 Hannover, Germany; (S.S.); (S.S.)
| | - Shu-Fen Coker
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
| | - Adam P. Kupinski
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
| | - Vineeta Tripathi
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
| | - Keith Foster
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
| | - Matthew Beard
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK; (S.D.); (M.E.); (S.-F.C.); (A.P.K.); (V.T.); (K.F.)
- Correspondence: (M.B.); (T.B.); Tel.: +44(0)7850-910340 (M.B.); +49(0)511-532-2859 (T.B.)
| | - Thomas Binz
- Institut für Zellbiochemie, OE 4310, Medizinische Hochschule Hannover, 30623 Hannover, Germany; (S.S.); (S.S.)
- Correspondence: (M.B.); (T.B.); Tel.: +44(0)7850-910340 (M.B.); +49(0)511-532-2859 (T.B.)
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7
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Almiron Bonnin DA, Havrda MC, Israel MA. Glioma Cell Secretion: A Driver of Tumor Progression and a Potential Therapeutic Target. Cancer Res 2018; 78:6031-6039. [PMID: 30333116 DOI: 10.1158/0008-5472.can-18-0345] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 05/30/2018] [Accepted: 08/14/2018] [Indexed: 11/16/2022]
Abstract
Cellular secretion is an important mediator of cancer progression. Secreted molecules in glioma are key components of complex autocrine and paracrine pathways that mediate multiple oncogenic pathologies. In this review, we describe tumor cell secretion in high-grade glioma and highlight potential novel therapeutic opportunities. Cancer Res; 78(21); 6031-9. ©2018 AACR.
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Affiliation(s)
- Damian A Almiron Bonnin
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Matthew C Havrda
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Mark A Israel
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire. .,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire.,Departments of Medicine and Pediatrics, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
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Sikorra S, Skiba M, Dorner MB, Weisemann J, Weil M, Valdezate S, Davletov B, Rummel A, Dorner BG, Binz T. Botulinum Neurotoxin F Subtypes Cleaving the VAMP-2 Q 58⁻K 59 Peptide Bond Exhibit Unique Catalytic Properties and Substrate Specificities. Toxins (Basel) 2018; 10:toxins10080311. [PMID: 30071628 PMCID: PMC6116196 DOI: 10.3390/toxins10080311] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/23/2018] [Accepted: 07/30/2018] [Indexed: 11/16/2022] Open
Abstract
In the recent past, about 40 botulinum neurotoxin (BoNT) subtypes belonging to serotypes A, B, E, and F pathogenic to humans were identified among hundreds of independent isolates. BoNTs are the etiological factors of botulism and represent potential bioweapons; however, they are also recognized pharmaceuticals for the efficient counteraction of hyperactive nerve terminals in a variety of human diseases. The detailed biochemical characterization of subtypes as the basis for development of suitable countermeasures and possible novel therapeutic applications is lagging behind the increase in new subtypes. Here, we report the primary structure of a ninth subtype of BoNT/F. Its amino-acid sequence diverges by at least 8.4% at the holotoxin and 13.4% at the enzymatic domain level from all other known BoNT/F subtypes. We found that BoNT/F9 shares the scissile Q58/K59 bond in its substrate vesicle associated membrane protein 2 with the prototype BoNT/F1. Comparative biochemical analyses of four BoNT/F enzymatic domains showed that the catalytic efficiencies decrease in the order F1 > F7 > F9 > F6, and vary by up to a factor of eight. KM values increase in the order F1 > F9 > F6 ≈ F7, whereas kcat decreases in the order F7 > F1 > F9 > F6. Comparative substrate scanning mutagenesis studies revealed a unique pattern of crucial substrate residues for each subtype. Based upon structural coordinates of F1 bound to an inhibitor polypeptide, the mutational analyses suggest different substrate interactions in the substrate binding channel of each subtype.
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Affiliation(s)
- Stefan Sikorra
- Institute of Cell Biochemistry, OE 4310, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
| | - Martin Skiba
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany.
| | - Martin B Dorner
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany.
| | - Jasmin Weisemann
- Institute of Toxicology, OE 5340, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
| | - Mirjam Weil
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany.
| | - Sylvia Valdezate
- Reference and Research Laboratory for Taxonomy, Spanish National Centre of Microbiology, Institute of Health Carlos III, 28220 Madrid, Spain.
| | - Bazbek Davletov
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
| | - Andreas Rummel
- Institute of Toxicology, OE 5340, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
| | - Brigitte G Dorner
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany.
| | - Thomas Binz
- Institute of Cell Biochemistry, OE 4310, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
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9
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Nugent M, Wang J, Lawrence G, Zurawski T, Geoghegan JA, Dolly JO. Conjugate of an IgG Binding Domain with Botulinum Neurotoxin A Lacking the Acceptor Moiety Targets Its SNARE Protease into TrkA-Expressing Cells When Coupled to Anti-TrkA IgG or Fc-βNGF. Bioconjug Chem 2017; 28:1684-1692. [PMID: 28489355 DOI: 10.1021/acs.bioconjchem.7b00157] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Numerous naturally occurring toxins can perturb biological systems when they invade susceptible cells. Coupling of pertinent targeting ligands to the active domains of such proteins provides a strategy for directing these to particular cellular populations implicated in disease. A novel approach described herein involved fusion of one mutated immunoglobulin G (IgG) binding moiety of staphylococcal protein A to the SNARE protease and translocation domain of botulinum neurotoxin A (BoNT/A). This chimera could be monovalently coupled to IgG or via its Fc region to recombinant targeting ligands. The utility of the resulting conjugates is demonstrated by the delivery of a SNARE protease into a cell line expressing tropomyosin receptor kinase A (TrkA) through coupling to anti-TrkA IgG or a fusion of Fc and nerve-growth factor. Thus, this is a versitile and innovative technology for conjugating toxins to diverse ligands for retargeted cell delivery of potential therapeutics.
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Affiliation(s)
- Marc Nugent
- International Centre for Neurotherapeutics, Dublin City University , Glasnevin, Dublin 9, Ireland
| | - Jiafu Wang
- International Centre for Neurotherapeutics, Dublin City University , Glasnevin, Dublin 9, Ireland
| | - Gary Lawrence
- International Centre for Neurotherapeutics, Dublin City University , Glasnevin, Dublin 9, Ireland
| | - Tomas Zurawski
- International Centre for Neurotherapeutics, Dublin City University , Glasnevin, Dublin 9, Ireland
| | - Joan A Geoghegan
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin , Dublin 2, Ireland
| | - J Oliver Dolly
- International Centre for Neurotherapeutics, Dublin City University , Glasnevin, Dublin 9, Ireland
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Current status and future directions of botulinum neurotoxins for targeting pain processing. Toxins (Basel) 2015; 7:4519-63. [PMID: 26556371 PMCID: PMC4663519 DOI: 10.3390/toxins7114519] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 09/29/2015] [Accepted: 10/19/2015] [Indexed: 12/20/2022] Open
Abstract
Current evidence suggests that botulinum neurotoxins (BoNTs) A1 and B1, given locally into peripheral tissues such as skin, muscles, and joints, alter nociceptive processing otherwise initiated by inflammation or nerve injury in animal models and humans. Recent data indicate that such locally delivered BoNTs exert not only local action on sensory afferent terminals but undergo transport to central afferent cell bodies (dorsal root ganglia) and spinal dorsal horn terminals, where they cleave SNAREs and block transmitter release. Increasing evidence supports the possibility of a trans-synaptic movement to alter postsynaptic function in neuronal and possibly non-neuronal (glial) cells. The vast majority of these studies have been conducted on BoNT/A1 and BoNT/B1, the only two pharmaceutically developed variants. However, now over 40 different subtypes of botulinum neurotoxins (BoNTs) have been identified. By combining our existing and rapidly growing understanding of BoNT/A1 and /B1 in altering nociceptive processing with explorations of the specific characteristics of the various toxins from this family, we may be able to discover or design novel, effective, and long-lasting pain therapeutics. This review will focus on our current understanding of the molecular mechanisms whereby BoNTs alter pain processing, and future directions in the development of these agents as pain therapeutics.
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11
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Sikorra S, Litschko C, Müller C, Thiel N, Galli T, Eichner T, Binz T. Identification and Characterization of Botulinum Neurotoxin A Substrate Binding Pockets and Their Re-Engineering for Human SNAP-23. J Mol Biol 2015; 428:372-384. [PMID: 26523682 DOI: 10.1016/j.jmb.2015.10.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/13/2015] [Accepted: 10/25/2015] [Indexed: 11/26/2022]
Abstract
Botulinum neurotoxins (BoNTs) are highly potent bacterial proteins that block neurotransmitter release at the neuromuscular junction by cleaving SNAREs (soluble N-ethyl maleimide sensitive factor attachment protein receptors). However, their serotype A (BoNT/A) that cleaves SNAP-25 (synaptosomal-associated protein of 25 kDa) has also been an established pharmaceutical for treatment of medical conditions that rely on hyperactivity of cholinergic nerve terminals for 25 years. The expansion of its use to a variety of further medical conditions associated with hypersecretion components is prevented partly because the involved SNARE isoforms are not cleaved. Therefore, we examined by mutational analyses the reason for the resistance of human SNAP-23, an isoform of SNAP-25. We show that replacement of 10 SNAP-23 residues with their SNAP-25 counterparts effects SNAP-25-like cleavability. Conversely, transfer of each of the replaced SNAP-23 residues to SNAP-25 drastically decreased the cleavability of SNAP-25. By means of the existing SNAP-25-toxin co-crystal structure, molecular dynamics simulations, and corroborative mutagenesis studies, the appropriate binding pockets for these residues in BoNT/A were characterized. Systematic mutagenesis of two major BoNT/A binding pockets was conducted in order to adapt these pockets to corresponding amino acids of human SNAP-23. Human SNAP-23 cleaving mutants were isolated using a newly established yeast-based screening system. This method may be useful for engineering novel BoNT/A pharmaceuticals for the treatment of diseases that rely on SNAP-23-mediated hypersecretion.
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Affiliation(s)
- Stefan Sikorra
- Institut für Physiologische Chemie, OE 4310, Medizinische Hochschule Hannover, D-30623 Hannover, Germany
| | - Christa Litschko
- Institut für Physiologische Chemie, OE 4310, Medizinische Hochschule Hannover, D-30623 Hannover, Germany
| | - Carina Müller
- Institut für Physiologische Chemie, OE 4310, Medizinische Hochschule Hannover, D-30623 Hannover, Germany
| | - Nadine Thiel
- Institut für Physiologische Chemie, OE 4310, Medizinische Hochschule Hannover, D-30623 Hannover, Germany
| | - Thierry Galli
- Sorbonne Paris Cité, Université Paris Diderot, Institut Jacques Monod, CNRS UMR 7592, INSERM ERL U950, F-75013 Paris, France
| | - Timo Eichner
- Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA
| | - Thomas Binz
- Institut für Physiologische Chemie, OE 4310, Medizinische Hochschule Hannover, D-30623 Hannover, Germany.
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12
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Andersson KE. Drug therapy of overactive bladder--what is coming next? Korean J Urol 2015; 56:673-9. [PMID: 26495067 PMCID: PMC4610893 DOI: 10.4111/kju.2015.56.10.673] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 09/03/2015] [Indexed: 01/25/2023] Open
Abstract
After the approval and introduction of mirabegron, tadalafil, and botulinum toxin A for treatment of lower urinary tract symptoms/overactive bladder, focus of interest has been on their place in therapy versus the previous gold standard, antimuscarinics. However, since these agents also have limitations there has been increasing interest in what is coming next - what is in the pipeline? Despite progress in our knowledge of different factors involved in both peripheral and central modulation of lower urinary tract dysfunction, there are few innovations in the pipe-line. Most developments concern modifications of existing principles (antimuscarinics, β3-receptor agonists, botulinum toxin A). However, there are several new and old targets/drugs of potential interest for further development, such as the purinergic and cannabinoid systems and the different members of the transient receptor potential channel family. However, even if there seems to be good rationale for further development of these principles, further exploration of their involvement in lower urinary tract function/dysfunction is necessary.
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Affiliation(s)
- Karl-Erik Andersson
- Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston Salem, NC, USA. ; Aarhus Institute for Advanced Sciences, Aarhus University, Aarhus, Denmark
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Abstract
INTRODUCTION Overactive bladder (OAB) is a common problem which can have disastrous effects on the quality of life of the sufferer. There are established treatments for the problem but they have significant adverse effects. Better drugs and new treatment modalities are necessary to deal with OAB. AREA COVERED Antimuscarinics, mirabegron and intravesical injection of botulinum toxin A are established treatments for OAB. Sacral neuromodulation is more invasive but has been successful in treating OAB. Phase II and III trials are in progress for newer β3-agonists and various combinations of antimuscarinics, β3-agonists and antidiuretics. Targeted secretion inhibitors (TSI) can increase efficacy and reduce adverse effects. Liposome integrated botulinum toxin A has an advantage of effective administration by intravesical instillation. Both medicines are in Phase II trials. Many other drugs which have promising results are discussed. EXPERT OPINION Newer antimuscarinics have better tolerability. Long-term data for mirabegron has shown that it is more effective in severe OAB. Combination drugs may prove to be more effective with less adverse effects. Emerging treatments with TSI, lipotoxin and gene therapy appear promising.
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Affiliation(s)
- Roopali Karmarkar
- a 1 Clinical Research Fellow, St Mary's Hospital, Imperial College, Urogynaecology Department , London, UK +44 0 79 83 41 40 71 ;
| | - Vik Khullar
- b 2 St Mary's Hospital, Imperial College, Urogynaecology Department , London, UK
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Kane CD, Nuss JE, Bavari S. Novel therapeutic uses and formulations of botulinum neurotoxins: a patent review (2012 - 2014). Expert Opin Ther Pat 2015; 25:675-90. [PMID: 25842964 DOI: 10.1517/13543776.2015.1030337] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Botulinum neurotoxins (BoNTs) are among the most toxic of known biological molecules and function as acetylcholine release inhibitors and neuromuscular blocking agents. Paradoxically, these properties also make them valuable therapeutic agents for the treatment of movement disorders, urological conditions and hypersecretory disorders. Greater understanding of their molecular mechanism of action and advances in protein engineering has led to significant efforts to improve and expand their function with a view towards broadening their therapeutic potential. AREAS COVERED Searches of Espacenet and Google Patent have revealed a number of patents related to BoNTs. This review will focus on novel therapeutic uses and formulations disclosed during 2012 - 2014. The seven patents discussed will include nanoformulations of FDA-approved BoNTs, additional BoNT subtypes and novel BoNT variants and chimeras created through protein engineering. Supporting patents and related publications are also briefly discussed. EXPERT OPINION The clinical and commercial success of BoNTs has prompted investigation into novel BoNTs or BoNT-mediated chimeras with promising in vitro results. Distinct strategies including the use of nanoformulations and targeted delivery have been implemented to identify new indication and improved functionality. Greater understanding of their systemic exposure, efficacy and safety profiles will be required for further development.
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Sacco E, Bientinesi R. Innovative pharmacotherapies for women with overactive bladder: where are we now and what is in the pipeline? Int Urogynecol J 2014; 26:629-40. [PMID: 25377296 DOI: 10.1007/s00192-014-2557-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/18/2014] [Indexed: 12/12/2022]
Abstract
INTRODUCTION AND HYPOTHESIS The impressive prevalence of overactive bladder (OAB) and the relevant limitations of current treatments urge the need for novel therapeutic approaches. METHODS A systematic literature and web search was performed to identify investigational drugs that entered the early and late phases of clinical development for women with OAB symptoms. RESULTS Approved pharmacological therapies for OAB (antimuscarinics, beta-3 agonists, and botulinum toxin) are evolving with the development of alternative administration methods, combination strategies, and novel compounds, expected to improve effectiveness, bladder selectivity, and dose flexibility. A wealth of investigational compounds, developed with both public and companies' indoor nonclinical disease-oriented studies, entered the early and late stages of clinical development in the last decade. Most non-anticholinergic compounds in ongoing clinical trials target central and peripheral neurotransmitter receptors involved in neurological modulation of micturition, nonadrenergic-noncholinergic mechanisms, cyclic nucleotide metabolism, different subtypes of ion channels or peripheral receptors of prostaglandins, vanilloids, vitamin D3, and opioids. Fascinating advances are ongoing also in the field of genetic therapy. CONCLUSIONS New pharmaceutical formulations and drug combinations are expected to be available in the next decade in order to overcome the limitations of current drugs for OAB. Although proof-of-concept, patient-oriented studies yielded disappointing results for several tentative drugs, a lot of clinical research is ongoing that is expected to provide clinicians with novel therapeutic agents in the near future.
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Affiliation(s)
- Emilio Sacco
- Department of Urology, "Agostino Gemelli" Hospital, Catholic University Medical School, Rome, Italy,
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Arsenault J, Cuijpers SAG, Ferrari E, Niranjan D, Rust A, Leese C, O'Brien JA, Binz T, Davletov B. Botulinum protease-cleaved SNARE fragments induce cytotoxicity in neuroblastoma cells. J Neurochem 2014; 129:781-91. [PMID: 24372287 PMCID: PMC4063335 DOI: 10.1111/jnc.12645] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 12/19/2013] [Accepted: 12/20/2013] [Indexed: 12/11/2022]
Abstract
Soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs) are crucial for exocytosis, trafficking, and neurite outgrowth, where vesicular SNAREs are directed toward their partner target SNAREs: synaptosomal-associated protein of 25 kDa and syntaxin. SNARE proteins are normally membrane bound, but can be cleaved and released by botulinum neurotoxins. We found that botulinum proteases types C and D can easily be transduced into endocrine cells using DNA-transfection reagents. Following administration of the C and D proteases into normally refractory Neuro2A neuroblastoma cells, the SNARE proteins were cleaved with high efficiency within hours. Remarkably, botulinum protease exposures led to cytotoxicity evidenced by spectrophotometric assays and propidium iodide penetration into the nuclei. Direct delivery of SNARE fragments into the neuroblastoma cells reduced viability similar to botulinum proteases' application. We observed synergistic cytotoxic effects of the botulinum proteases, which may be explained by the release and interaction of soluble SNARE fragments. We show for the first time that previously observed cytotoxicity of botulinum neurotoxins/C in neurons could be achieved in cells of neuroendocrine origin with implications for medical uses of botulinum preparations.
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Somm E, Bonnet N, Zizzari P, Tolle V, Toulotte A, Jones R, Epelbaum J, Martinez A, Hüppi PS, Aubert ML. Comparative inhibition of the GH/IGF-I axis obtained with either the targeted secretion inhibitor SXN101959 or the somatostatin analog octreotide in growing male rats. Endocrinology 2013; 154:4237-48. [PMID: 24029240 DOI: 10.1210/en.2013-1427] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abnormally high GH/IGF-I levels, most often caused by adenomas arising from pituitary somatotrophs, generate deleterious effects. We recently described a targeted secretion inhibitor (SXN101742) comprising a GHRH domain and the endopeptidase domain of botulinum toxin serotype D (GHRH-light chain endopeptidase type D domain [LC/D] associated to a heavy chain translocation domain [HN]) able to down-regulate the GH/IGF-I axis. In the present study, we compared the effect of a single iv bolus of a related molecule developed for clinical studies (SXN101959, 1 mg/kg) with a sc infusion of the somatostatin analog octreotide (SMS201-995, 10 μg/kg · h) to lower GH/IGF-I activity in growing male rats. Ten days after administration of SXN101959 or initiation of the octreotide infusion, body and pituitary weights, body length, GH peaks, and IGF-I production were reduced by both treatments but to a greater extent with SXN101959. In contrast to unaltered GH gene expression and increased GH storage in pituitaries from octreotide-treated rats, the inhibition of GH secretion was associated with a collapse of both GH mRNA and protein level in pituitaries from SXN101959-treated rats, in line with a specific decrease in hypothalamic GHRH production, not observed with octreotide. SXN101959 did not induce major apoptotic events in anterior pituitary and exhibited a reversible mode of action with full recovery of somatotroph cell functionality 30 days after treatment. Octreotide infusion permanently decreased ghrelin levels, whereas SXN101959 only transiently attenuated ghrelinemia. Both treatments limited bone mass acquisition and altered specifically tissues development. In conclusion, SXN101959 exerts a powerful and reversible inhibitory action on the somatotropic axis. Specific features of SXN101959, including long duration of action coupled to a strong inhibition of pituitary GH synthesis, represent advantages when treating overproduction of GH.
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Affiliation(s)
- Emmanuel Somm
- Division of Development and Growth, Department of Pediatrics, University of Geneva School of Medicine, 1211 Geneva 14, Switzerland.
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Masuyer G, Chaddock JA, Foster KA, Acharya KR. Engineered botulinum neurotoxins as new therapeutics. Annu Rev Pharmacol Toxicol 2013; 54:27-51. [PMID: 24016211 DOI: 10.1146/annurev-pharmtox-011613-135935] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Botulinum neurotoxins (BoNTs) cause flaccid paralysis by inhibiting neurotransmission at cholinergic nerve terminals. Each BoNT consists of three domains that are essential for toxicity: the binding domain, the translocation domain, and the catalytic light-chain domain. BoNT modular architecture is associated with a multistep mechanism that culminates in the intracellular proteolysis of SNARE (soluble N-ethylmaleimide-sensitive-fusion-protein attachment protein receptor) proteins, which prevents synaptic vesicle exocytosis. As the most toxic proteins known, BoNTs have been extensively studied and are used as pharmaceutical agents to treat an increasing variety of disorders. This review summarizes the level of sophistication reached in BoNT engineering and highlights the diversity of approaches taken to utilize the modularity of the toxin. Improved efficiency and applicability have been achieved by direct mutagenesis and interserotype domain rearrangement. The scope of BoNT activity has been extended to nonneuronal cells and offers the basis for novel biomolecules in the treatment of secretion disorders.
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Affiliation(s)
- Geoffrey Masuyer
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom;
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Arsenault J, Ferrari E, Niranjan D, Cuijpers SAG, Gu C, Vallis Y, O'Brien J, Davletov B. Stapling of the botulinum type A protease to growth factors and neuropeptides allows selective targeting of neuroendocrine cells. J Neurochem 2013; 126:223-33. [PMID: 23638840 PMCID: PMC3758956 DOI: 10.1111/jnc.12284] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 04/16/2013] [Accepted: 04/24/2013] [Indexed: 01/12/2023]
Abstract
Precise cellular targeting of macromolecular cargos has important biotechnological and medical implications. Using a recently established ‘protein stapling’ method, we linked the proteolytic domain of botulinum neurotoxin type A (BoNT/A) to a selection of ligands to target neuroendocrine tumor cells. The botulinum proteolytic domain was chosen because of its well-known potency to block the release of neurotransmitters and hormones. Among nine tested stapled ligands, the epidermal growth factor was able to deliver the botulinum enzyme into pheochromocytoma PC12 and insulinoma Min6 cells; ciliary neurotrophic factor was effective on neuroblastoma SH-SY5Y and Neuro2A cells, whereas corticotropin-releasing hormone was active on pituitary AtT-20 cells and the two neuroblastoma cell lines. In neuronal cultures, the epidermal growth factor- and ciliary neurotrophic factor-directed botulinum enzyme targeted distinct subsets of neurons whereas the whole native neurotoxin targeted the cortical neurons indiscriminately. At nanomolar concentrations, the retargeted botulinum molecules were able to inhibit stimulated release of hormones from tested cell lines suggesting their application for treatments of neuroendocrine disorders.
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Affiliation(s)
- Jason Arsenault
- MRC Laboratory of Molecular Biology, Neurobiology, Cambridge, UK
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IGF-1 antibody prolongs the effective duration time of botulinum toxin in decreasing muscle strength. Int J Mol Sci 2013; 14:9051-61. [PMID: 23698763 PMCID: PMC3676772 DOI: 10.3390/ijms14059051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 03/28/2013] [Accepted: 04/15/2013] [Indexed: 12/12/2022] Open
Abstract
Botulinum toxin type-A (Btx-A), a powerful therapeutic tool in various medical specialties, requires repeated injections to maintain its effect. Therefore, novel methods to prolong the effective duration time of Btx-A are highly needed. Rats were assigned to three major groups: control group (n = 30), Btx-A group (n = 30), and IGF-1 Ab groups. IGF-1 Ab groups were composed by sub-groups A1-A5 (each has 25 rats) for the subsequent IGF-1Ab dose-effect study. Muscle strength was determined by a survey system for rat lower limbs nerve and muscle function. Muscle-specific receptor tyrosine kinase (MuSK), Insulin-like growth factor binding protein-5 (IGFBP5), and growth-associated protein, 43-kDa (GAP43) were determined by real-time polymerase chain reactions (PCRs) and Western blot. We found that Btx-A decreased the muscle strength, with a paralysis maintained for 70 days. IGF-1Ab prolonged the effective duration time of Btx-A. Real-time PCRs and Western blot showed that IGF-1Ab delayed the increase of MuSK and IGFBP5 after Btx-A injection, without affecting GAP43. These results indicate that IGF-1Ab might prolong the effective duration time of Btx-A on muscle strength through delaying the increase of MuSK. It would be interesting to determine whether IGF-1Ab can be used as an auxiliary measure to the Btx-A treatment in the future.
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Somm E, Bonnet N, Martinez A, Marks PMH, Cadd VA, Elliott M, Toulotte A, Ferrari SL, Rizzoli R, Hüppi PS, Harper E, Melmed S, Jones R, Aubert ML. A botulinum toxin-derived targeted secretion inhibitor downregulates the GH/IGF1 axis. J Clin Invest 2012; 122:3295-306. [PMID: 22850878 DOI: 10.1172/jci63232] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 06/14/2012] [Indexed: 01/15/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are zinc endopeptidases that block release of the neurotransmitter acetylcholine in neuromuscular synapses through cleavage of soluble N-ethylmaleimide-sensitive fusion (NSF) attachment protein receptor (SNARE) proteins, which promote fusion of synaptic vesicles to the plasma membrane. We designed and tested a BoNT-derived targeted secretion inhibitor (TSI) targeting pituitary somatotroph cells to suppress growth hormone (GH) secretion and treat acromegaly. This recombinant protein, called SXN101742, contains a modified GH-releasing hormone (GHRH) domain and the endopeptidase domain of botulinum toxin serotype D (GHRH-LHN/D, where HN/D indicates endopeptidase and translocation domain type D). In vitro, SXN101742 targeted the GHRH receptor and depleted a SNARE protein involved in GH exocytosis, vesicle-associated membrane protein 2 (VAMP2). In vivo, administering SXN101742 to growing rats produced a dose-dependent inhibition of GH synthesis, storage, and secretion. Consequently, hepatic IGF1 production and resultant circulating IGF1 levels were reduced. Accordingly, body weight, body length, organ weight, and bone mass acquisition were all decreased, reflecting the biological impact of SXN101742 on the GH/IGF1 axis. An inactivating 2-amino acid substitution within the zinc coordination site of the endopeptidase domain completely abolished SXN101742 inhibitory actions on GH and IGF1. Thus, genetically reengineered BoNTs can be targeted to nonneural cells to selectively inhibit hormone secretion, representing a new approach to treating hormonal excess.
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Affiliation(s)
- Emmanuel Somm
- Department of Paediatrics, University of Geneva School of Medicine, Genevea, Switzerland.
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Transforming the Domain Structure of Botulinum Neurotoxins into Novel Therapeutics. Curr Top Microbiol Immunol 2012. [DOI: 10.1007/978-3-662-45790-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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