1
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McElvaney OF, Fraughen DD, McElvaney OJ, Carroll TP, McElvaney NG. Alpha-1 antitrypsin deficiency: current therapy and emerging targets. Expert Rev Respir Med 2023; 17:191-202. [PMID: 36896570 DOI: 10.1080/17476348.2023.2174973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
INTRODUCTION Alpha1 antitrypsin deficiency (AATD), a common hereditary disorder affecting mainly lungs, liver and skin has been the focus of some of the most exciting therapeutic approaches in medicine in the past 5 years. In this review, we discuss the therapies presently available for the different manifestations of AATD and new therapies in the pipeline. AREAS COVERED We review therapeutic options for the individual lung, liver and skin manifestations of AATD along with approaches which aim to treat all three. Along with this renewed interest in treating AATD come challenges. How is AAT best delivered to the lung? What is the desired level of AAT in the circulation and lungs which therapeutics should aim to provide? Will treating the liver disease increase the potential for lung disease? Are there treatments to target the underlying genetic defect with the potential to prevent all aspects of AATDrelated disease? EXPERT OPINION With a relatively small population able to participate in clinical studies, increased awareness and diagnosis of AATD is urgently needed. Better, more sensitive clinical parameters will assist in the generation of acceptable and robust evidence of therapeutic effect for current and emerging treatments.
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Affiliation(s)
- Oisín F McElvaney
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
| | - Daniel D Fraughen
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
| | - Oliver J McElvaney
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
| | - Tomás P Carroll
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland.,Alpha-1 Foundation Ireland, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Noel G McElvaney
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
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2
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Fromme M, Schneider CV, Trautwein C, Brunetti-Pierri N, Strnad P. Alpha-1 antitrypsin deficiency: A re-surfacing adult liver disorder. J Hepatol 2022; 76:946-958. [PMID: 34848258 DOI: 10.1016/j.jhep.2021.11.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 11/05/2021] [Accepted: 11/18/2021] [Indexed: 12/21/2022]
Abstract
Alpha-1 antitrypsin deficiency (AATD) arises from mutations in the SERPINA1 gene encoding alpha-1 antitrypsin (AAT) that lead to AAT retention in the endoplasmic reticulum of hepatocytes, causing proteotoxic liver injury and loss-of-function lung disease. The homozygous Pi∗Z mutation (Pi∗ZZ genotype) is responsible for the majority of severe AATD cases and can precipitate both paediatric and adult liver diseases, while the heterozygous Pi∗Z mutation (Pi∗MZ genotype) is an established genetic modifier of liver disease. We review genotype-related hepatic phenotypes/disease predispositions. We also describe the mechanisms and factors promoting the development of liver disease, as well as approaches to evaluate the extent of liver fibrosis. Finally, we discuss emerging diagnostic and therapeutic approaches for the clinical management of this often neglected disorder.
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Affiliation(s)
- Malin Fromme
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Aachen, Germany
| | - Carolin V Schneider
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Aachen, Germany
| | - Christian Trautwein
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Aachen, Germany
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine, Pozzuoli, 80078 Naples, Italy; Department of Translational Medicine, Federico II University of Naples, Naples, Italy
| | - Pavel Strnad
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Aachen, Germany.
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3
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McNulty MJ, Silberstein DZ, Kuhn BT, Padgett HS, Nandi S, McDonald KA, Cross CE. Alpha-1 antitrypsin deficiency and recombinant protein sources with focus on plant sources: Updates, challenges and perspectives. Free Radic Biol Med 2021; 163:10-30. [PMID: 33279618 DOI: 10.1016/j.freeradbiomed.2020.11.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 12/16/2022]
Abstract
Alpha-1 antitrypsin deficiency (A1ATD) is an autosomal recessive disease characterized by low plasma levels of A1AT, a serine protease inhibitor representing the most abundant circulating antiprotease normally present at plasma levels of 1-2 g/L. The dominant clinical manifestations include predispositions to early onset emphysema due to protease/antiprotease imbalance in distal lung parenchyma and liver disease largely due to unsecreted polymerized accumulations of misfolded mutant A1AT within the endoplasmic reticulum of hepatocytes. Since 1987, the only FDA licensed specific therapy for the emphysema component has been infusions of A1AT purified from pooled human plasma at the 2020 cost of up to US $200,000/year with the risk of intermittent shortages. In the past three decades various, potentially less expensive, recombinant forms of human A1AT have reached early stages of development, one of which is just reaching the stage of human clinical trials. The focus of this review is to update strategies for the treatment of the pulmonary component of A1ATD with some focus on perspectives for therapeutic production and regulatory approval of a recombinant product from plants. We review other competitive technologies for treating the lung disease manifestations of A1ATD, highlight strategies for the generation of data potentially helpful for securing FDA Investigational New Drug (IND) approval and present challenges in the selection of clinical trial strategies required for FDA licensing of a New Drug Approval (NDA) for this disease.
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Affiliation(s)
- Matthew J McNulty
- Department of Chemical Engineering, University of California, Davis, CA, USA
| | - David Z Silberstein
- Department of Chemical Engineering, University of California, Davis, CA, USA
| | - Brooks T Kuhn
- Department of Internal Medicine, University of California, Davis, CA, USA; University of California, Davis, Alpha-1 Deficiency Clinic, Sacramento, CA, USA
| | | | - Somen Nandi
- Department of Chemical Engineering, University of California, Davis, CA, USA; Global HealthShare Initiative®, University of California, Davis, CA, USA
| | - Karen A McDonald
- Department of Chemical Engineering, University of California, Davis, CA, USA; Global HealthShare Initiative®, University of California, Davis, CA, USA
| | - Carroll E Cross
- Department of Internal Medicine, University of California, Davis, CA, USA; University of California, Davis, Alpha-1 Deficiency Clinic, Sacramento, CA, USA; Department of Physiology and Membrane Biology, University of California, Davis, CA, USA.
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4
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Quinn M, Ellis P, Pye A, Turner AM. Obstacles to Early Diagnosis and Treatment of Alpha-1 Antitrypsin Deficiency: Current Perspectives. Ther Clin Risk Manag 2020; 16:1243-1255. [PMID: 33364772 PMCID: PMC7751439 DOI: 10.2147/tcrm.s234377] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/30/2020] [Indexed: 11/23/2022] Open
Abstract
This review summarizes the current research and outlooks regarding the obstacles to diagnosing and treating early alpha-1-antitrypsin deficiency (AATD). It draws on prior systematic reviews and expert surveys to discover precisely what difficulties exist in early diagnosis and treatment of AATD and elucidate potential solutions to ease these difficulties. The perceived rarity of AATD may translate to a condition poorly understood by primary care physicians, and even many respiratory physicians, which results in opportunities for diagnosis being missed, especially in mild or asymptomatic patients. There are diagnostic techniques involving biomarkers and home testing methods which could improve the rate of early diagnosis. With respect to treatment, AATD involves treating two separate pathologies, lung disease and liver disease. The only specific AATD treatment, augmentation therapy, has proven ability in treating lung disease but not liver disease. Alpha-1-antitrypsin (AAT) synthesized in the liver can form damaging polymers that also result in reduced circulating AAT levels and, whilst liver transplantation is used to effectively treat AATD, it is inappropriate in early disease. Novel therapeutic areas such as gene editing and increasing autophagy are therefore being researched as future treatments. Ultimately, diagnosis and treatment are intrinsically linked in AATD, with earlier diagnosis leading to better treatment options and thus better patient outcomes.
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Affiliation(s)
- Mark Quinn
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - Paul Ellis
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - Anita Pye
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - Alice M Turner
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK.,University Hospitals Birmingham, Birmingham, UK
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5
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Faull SV, Elliston ELK, Gooptu B, Jagger AM, Aldobiyan I, Redzej A, Badaoui M, Heyer-Chauhan N, Rashid ST, Reynolds GM, Adams DH, Miranda E, Orlova EV, Irving JA, Lomas DA. The structural basis for Z α 1-antitrypsin polymerization in the liver. SCIENCE ADVANCES 2020; 6:6/43/eabc1370. [PMID: 33087346 PMCID: PMC7577719 DOI: 10.1126/sciadv.abc1370] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 09/08/2020] [Indexed: 05/22/2023]
Abstract
The serpinopathies are among a diverse set of conformational diseases that involve the aberrant self-association of proteins into ordered aggregates. α1-Antitrypsin deficiency is the archetypal serpinopathy and results from the formation and deposition of mutant forms of α1-antitrypsin as "polymer" chains in liver tissue. No detailed structural analysis has been performed of this material. Moreover, there is little information on the relevance of well-studied artificially induced polymers to these disease-associated molecules. We have isolated polymers from the liver tissue of Z α1-antitrypsin homozygotes (E342K) who have undergone transplantation, labeled them using a Fab fragment, and performed single-particle analysis of negative-stain electron micrographs. The data show structural equivalence between heat-induced and ex vivo polymers and that the intersubunit linkage is best explained by a carboxyl-terminal domain swap between molecules of α1-antitrypsin.
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Affiliation(s)
- Sarah V Faull
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK
| | - Emma L K Elliston
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BN, UK
| | - Bibek Gooptu
- Leicester Institute of Structural and Chemical Biology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 7HB, UK
- National Institute for Health Research (NIHR) Leicester BRC-Respiratory, Leicester, UK
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, University of London, London WC1E 7HX, UK
| | - Alistair M Jagger
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BN, UK
| | - Ibrahim Aldobiyan
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BN, UK
| | - Adam Redzej
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, University of London, London WC1E 7HX, UK
| | - Magd Badaoui
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK
| | - Nina Heyer-Chauhan
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BN, UK
| | - S Tamir Rashid
- Centre for Stem Cells and Regenerative Medicine and Institute for Liver Studies, King's College London, London WC2R 2LS, UK
| | - Gary M Reynolds
- Centre for Liver Research and NIHR Birmingham Liver Biomedical Research Unit, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, UK
| | - David H Adams
- Centre for Liver Research and NIHR Birmingham Liver Biomedical Research Unit, Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, UK
| | - Elena Miranda
- Department of Biology and Biotechnologies "Charles Darwin" and Pasteur Institute-Cenci Bolognetti Foundation, Sapienza University of Rome, Rome, Italy
| | - Elena V Orlova
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, University of London, London WC1E 7HX, UK
| | - James A Irving
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK.
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BN, UK
| | - David A Lomas
- UCL Respiratory, University College London, 5 University Street, London WC1E 6JF, UK.
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BN, UK
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6
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Singh AK, Wadsworth PA, Tapia CM, Aceto G, Ali SR, Chen H, D'Ascenzo M, Zhou J, Laezza F. Mapping of the FGF14:Nav1.6 complex interface reveals FLPK as a functionally active peptide modulating excitability. Physiol Rep 2020; 8:e14505. [PMID: 32671946 PMCID: PMC7363588 DOI: 10.14814/phy2.14505] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 02/07/2023] Open
Abstract
The voltage-gated sodium (Nav) channel complex is comprised of pore-forming α subunits (Nav1.1-1.9) and accessory regulatory proteins such as the intracellular fibroblast growth factor 14 (FGF14). The cytosolic Nav1.6 C-terminal tail binds directly to FGF14 and this interaction modifies Nav1.6-mediated currents with effects on intrinsic excitability in the brain. Previous studies have identified the FGF14V160 residue within the FGF14 core domain as a hotspot for the FGF14:Nav1.6 complex formation. Here, we used three short amino acid peptides around FGF14V160 to probe for the FGF14 interaction with the Nav1.6 C-terminal tail and to evaluate the activity of the peptide on Nav1.6-mediated currents. In silico docking predicts FLPK to bind to FGF14V160 with the expectation of interfering with the FGF14:Nav1.6 complex formation, a phenotype that was confirmed by the split-luciferase assay (LCA) and surface plasmon resonance (SPR), respectively. Whole-cell patch-clamp electrophysiology studies demonstrate that FLPK is able to prevent previously reported FGF14-dependent phenotypes of Nav1.6 currents, but that its activity requires the FGF14 N-terminal tail, a domain that has been shown to contribute to Nav1.6 inactivation independently from the FGF14 core domain. In medium spiny neurons in the nucleus accumbens, where both FGF14 and Nav1.6 are abundantly expressed, FLPK significantly increased firing frequency by a mechanism consistent with the ability of the tetrapeptide to interfere with Nav1.6 inactivation and potentiate persistent Na+ currents. Taken together, these results indicate that FLPK might serve as a probe for characterizing molecular determinants of neuronal excitability and a peptide scaffold to develop allosteric modulators of Nav channels.
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Affiliation(s)
- Aditya K. Singh
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
| | - Paul A. Wadsworth
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
- M.D.‐Ph.D. Combined Degree ProgramUniversità Cattolica del Sacro CuoreRomeItaly
- Biochemistry and Molecular Biology Graduate ProgramUniversità Cattolica del Sacro CuoreRomeItaly
| | - Cynthia M. Tapia
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
- NIEHS Environmental Toxicology Training ProgramUniversità Cattolica del Sacro CuoreRomeItaly
| | - Giuseppe Aceto
- Institute of Human PhysiologyUniversità Cattolica del Sacro CuoreRomeItaly
- Department of NeuroscienceUniversità Cattolica del Sacro CuoreRomeItaly
- Fondazione Policlinico Universitario A. GemelliIRCCSRomeItaly
| | - Syed R. Ali
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
| | - Haiying Chen
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
| | - Marcello D'Ascenzo
- Institute of Human PhysiologyUniversità Cattolica del Sacro CuoreRomeItaly
- Department of NeuroscienceUniversità Cattolica del Sacro CuoreRomeItaly
- Fondazione Policlinico Universitario A. GemelliIRCCSRomeItaly
| | - Jia Zhou
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
- Center for Addiction ResearchUniversity of Texas Medical BranchGalvestonTXUSA
| | - Fernanda Laezza
- Department of Pharmacology & ToxicologyUniversità Cattolica del Sacro CuoreRomeItaly
- Center for Addiction ResearchUniversity of Texas Medical BranchGalvestonTXUSA
- Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTXUSA
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7
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Pye A, Turner AM. Experimental and investigational drugs for the treatment of alpha-1 antitrypsin deficiency. Expert Opin Investig Drugs 2019; 28:891-902. [PMID: 31550938 DOI: 10.1080/13543784.2019.1672656] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Introduction: Alpha-1 antitrypsin deficiency (AATD) is most often associated with chronic lung disease, early onset emphysema, and liver disease. The standard of care in lung disease due to AATD is alpha-1 antitrypsin augmentation but there are several new and emerging treatment options under investigation for both lung and liver manifestations. Areas covered: We review therapeutic approaches to lung and liver disease in alpha-1 antitrypsin deficiency (AATD) and the agents in clinical development according to their mode of action. The focus is on products in clinical trials, but data from pre-clinical studies are described where relevant, particularly where progression to trials appears likely. Expert opinion: Clinical trials directed at lung and liver disease separately are now taking place. Multimodality treatment may be the future, but this could be limited by treatment costs. The next 5-10 years may reveal new guidance on when to use therapeutics for slowing disease progression with personalized treatment regimes coming to the forefront.
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Affiliation(s)
- Anita Pye
- Institute of Applied Health Research, University of Birmingham , Birmingham , UK
| | - Alice M Turner
- Institute of Applied Health Research, University of Birmingham , Birmingham , UK
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8
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Motamedi-Shad N, Jagger AM, Liedtke M, Faull SV, Nanda AS, Salvadori E, Wort JL, Kay CW, Heyer-Chauhan N, Miranda E, Perez J, Ordóñez A, Haq I, Irving JA, Lomas DA. An antibody that prevents serpin polymerisation acts by inducing a novel allosteric behaviour. Biochem J 2016; 473:3269-90. [PMID: 27407165 PMCID: PMC5264506 DOI: 10.1042/bcj20160159] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 07/08/2016] [Accepted: 07/12/2016] [Indexed: 11/30/2022]
Abstract
Serpins are important regulators of proteolytic pathways with an antiprotease activity that involves a conformational transition from a metastable to a hyperstable state. Certain mutations permit the transition to occur in the absence of a protease; when associated with an intermolecular interaction, this yields linear polymers of hyperstable serpin molecules, which accumulate at the site of synthesis. This is the basis of many pathologies termed the serpinopathies. We have previously identified a monoclonal antibody (mAb4B12) that, in single-chain form, blocks α1-antitrypsin (α1-AT) polymerisation in cells. Here, we describe the structural basis for this activity. The mAb4B12 epitope was found to encompass residues Glu32, Glu39 and His43 on helix A and Leu306 on helix I. This is not a region typically associated with the serpin mechanism of conformational change, and correspondingly the epitope was present in all tested structural forms of the protein. Antibody binding rendered β-sheet A - on the opposite face of the molecule - more liable to adopt an 'open' state, mediated by changes distal to the breach region and proximal to helix F. The allosteric propagation of induced changes through the molecule was evidenced by an increased rate of peptide incorporation and destabilisation of a preformed serpin-enzyme complex following mAb4B12 binding. These data suggest that prematurely shifting the β-sheet A equilibrium towards the 'open' state out of sequence with other changes suppresses polymer formation. This work identifies a region potentially exploitable for a rational design of ligands that is able to dynamically influence α1-AT polymerisation.
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Affiliation(s)
- Neda Motamedi-Shad
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - Alistair M. Jagger
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - Maximilian Liedtke
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
| | - Sarah V. Faull
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/Medical Research Council Building, Hills Road, Cambridge CB2 0XY, U.K
| | - Arjun Scott Nanda
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - Enrico Salvadori
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
- London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, U.K
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, U.K
| | - Joshua L. Wort
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - Christopher W.M. Kay
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
- London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, U.K
| | - Narinder Heyer-Chauhan
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - Elena Miranda
- Department of Biology and Biotechnologies ‘Charles Darwin’, Sapienza University of Rome, Rome 00185, Italy
| | - Juan Perez
- Departamento de Biologia Celular, Genetica y Fisiologia, Facultad de Ciencias, Campus Teatinos, Universidad de Malaga, Malaga 29071, Spain
| | - Adriana Ordóñez
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/Medical Research Council Building, Hills Road, Cambridge CB2 0XY, U.K
| | - Imran Haq
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - James A. Irving
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
| | - David A. Lomas
- Centre for Respiratory Biology, UCL Respiratory, University College London, London WC1E 6JF, U.K
- Institute of Structural and Molecular Biology/Birkbeck, University of London, London WC1E 7HX, U.K
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9
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Amso Z, Kowalczyk R, Watson M, Park YE, Callon KE, Musson DS, Cornish J, Brimble MA. Structure activity relationship study on the peptide hormone preptin, a novel bone-anabolic agent for the treatment of osteoporosis. Org Biomol Chem 2016; 14:9225-9238. [PMID: 27488745 DOI: 10.1039/c6ob01455k] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Preptin is a 34-residue pancreatic hormone shown to be anabolic to bone in vitro and in vivo. The bone activity of preptin resides within the (1-16) N-terminal fragment. Due to its peptidic nature, the truncated fragment of preptin is enzymatically unstable; however it provides an attractive framework for the creation of stable analogues using various peptidomimetic techniques. An alanine scan of preptin (1-16) was undertaken which showed that substitution of Ser at position 3 or Pro at position 14 did not inhibit the proliferative activity of preptin in primary rat osteoblasts (bone-forming cells). Importantly, Ser-3 to Ala substitution also showed a significant activity on osteoblast differentiation in vitro and increased the formation of mineralised bone matrix. Additional modifications with non-proteinogenic amino acids at position 3 improved the stability in liver microsomes, but diminished the osteoblast proliferative activity. In addition, to provide greater structural diversity, a series of macrocyclic preptin (1-16) analogues was synthesised using head-to-tail and head-to-side chain macrolactamisation as well as ring-closing metathesis. However, a detrimental effect on osteoblast activity was observed upon macrocyclisation.
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Affiliation(s)
- Zaid Amso
- School of Chemical Sciences, The University of Auckland, 23 Symonds St, Auckland 1142, New Zealand.
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10
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Nyon MP, Prentice T, Day J, Kirkpatrick J, Sivalingam GN, Levy G, Haq I, Irving JA, Lomas DA, Christodoulou J, Gooptu B, Thalassinos K. An integrative approach combining ion mobility mass spectrometry, X-ray crystallography, and nuclear magnetic resonance spectroscopy to study the conformational dynamics of α1 -antitrypsin upon ligand binding. Protein Sci 2015; 24:1301-12. [PMID: 26011795 PMCID: PMC4534181 DOI: 10.1002/pro.2706] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 05/05/2015] [Accepted: 05/11/2015] [Indexed: 11/11/2022]
Abstract
Native mass spectrometry (MS) methods permit the study of multiple protein species within solution equilibria, whereas ion mobility (IM)-MS can report on conformational behavior of specific states. We used IM-MS to study a conformationally labile protein (α1 -antitrypsin) that undergoes pathological polymerization in the context of point mutations. The folded, native state of the Z-variant remains highly polymerogenic in physiological conditions despite only minor thermodynamic destabilization relative to the wild-type variant. Various data implicate kinetic instability (conformational lability within a native state ensemble) as the basis of Z α1 -antitrypsin polymerogenicity. We show the ability of IM-MS to track such disease-relevant conformational behavior in detail by studying the effects of peptide binding on α1 -antitrypsin conformation and dynamics. IM-MS is, therefore, an ideal platform for the screening of compounds that result in therapeutically beneficial kinetic stabilization of native α1 -antitrypsin. Our findings are confirmed with high-resolution X-ray crystallographic and nuclear magnetic resonance spectroscopic studies of the same event, which together dissect structural changes from dynamic effects caused by peptide binding at a residue-specific level. IM-MS methods, therefore, have great potential for further study of biologically relevant thermodynamic and kinetic instability of proteins and provide rapid and multidimensional characterization of ligand interactions of therapeutic interest.
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Affiliation(s)
- Mun Peak Nyon
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Tanya Prentice
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Jemma Day
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - John Kirkpatrick
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Ganesh N Sivalingam
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Geraldine Levy
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Imran Haq
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London, WC1E 6BT, United Kingdom
| | - James A Irving
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London, WC1E 6BT, United Kingdom
| | - David A Lomas
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London, WC1E 6BT, United Kingdom
| | - John Christodoulou
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom.,Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, London, WC1E 7HX, United Kingdom
| | - Bibek Gooptu
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, London, WC1E 7HX, United Kingdom.,Division of Asthma, Allergy and Lung Biology, King's College London, Guy's Hospital, London, SE1 9RT, United Kingdom
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Biosciences, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom.,Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, London, WC1E 7HX, United Kingdom
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11
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Ordóñez A, Pérez J, Tan L, Dickens JA, Motamedi-Shad N, Irving JA, Haq I, Ekeowa U, Marciniak SJ, Miranda E, Lomas DA. A single-chain variable fragment intrabody prevents intracellular polymerization of Z α1-antitrypsin while allowing its antiproteinase activity. FASEB J 2015; 29:2667-78. [PMID: 25757566 PMCID: PMC4548814 DOI: 10.1096/fj.14-267351] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 02/19/2015] [Indexed: 01/10/2023]
Abstract
Mutant Z α1-antitrypsin (E342K) accumulates as polymers within the endoplasmic reticulum (ER) of hepatocytes predisposing to liver disease, whereas low levels of circulating Z α1-antitrypsin lead to emphysema by loss of inhibition of neutrophil elastase. The ideal therapy should prevent polymer formation while preserving inhibitory activity. Here we used mAb technology to identify interactors with Z α1-antitrypsin that comply with both requirements. We report the generation of an mAb (4B12) that blocked α1-antitrypsin polymerization in vitro at a 1:1 molar ratio, causing a small increase of the stoichiometry of inhibition for neutrophil elastase. A single-chain variable fragment (scFv) intrabody was generated based on the sequence of mAb4B12. The expression of scFv4B12 within the ER (scFv4B12KDEL) and along the secretory pathway (scFv4B12) reduced the intracellular polymerization of Z α1-antitrypsin by 60%. The scFv4B12 intrabody also increased the secretion of Z α1-antitrypsin that retained inhibitory activity against neutrophil elastase. MAb4B12 recognized a discontinuous epitope probably located in the region of helices A/C/G/H/I and seems to act by altering protein dynamics rather than binding preferentially to the native state. This novel approach could reveal new target sites for small-molecule intervention that may block the transition to aberrant polymers without compromising the inhibitory activity of Z α1-antitrypsin.—Ordóñez, A., Pérez, J., Tan, L., Dickens, J. A., Motamedi-Shad, N., Irving, J. A., Haq, I., Ekeowa, U., Marciniak, S. J., Miranda, E., Lomas, D. A. A single-chain variable fragment intrabody prevents intracellular polymerization of Z α1-antitrypsin while allowing its antiproteinase activity.
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Affiliation(s)
- Adriana Ordóñez
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Juan Pérez
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Lu Tan
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Jennifer A Dickens
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Neda Motamedi-Shad
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - James A Irving
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Imran Haq
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Ugo Ekeowa
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Stefan J Marciniak
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - Elena Miranda
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
| | - David A Lomas
- *Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom; Department of Cell Biology, Genetics and Physiology, University of Malaga, Malaga, Spain; Wolfson Institute for Biomedical Research, University College London, London, United Kingdom; and Department of Biology and Biotechnologies, "Charles Darwin," and Pasteur Institute, Cenci Bolognetti Foundation, Sapienza University, Rome, Italy
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12
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Wang W, Woodbury NW. Unstructured interactions between peptides and proteins: exploring the role of sequence motifs in affinity and specificity. Acta Biomater 2015; 11:88-95. [PMID: 25266506 DOI: 10.1016/j.actbio.2014.09.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 09/17/2014] [Accepted: 09/22/2014] [Indexed: 11/30/2022]
Abstract
Unstructured interactions between proteins and other molecules or surfaces are often described as nonspecific, and have received relatively little attention in terms of their role in biology. However, despite their lack of a specific binding structure, these unstructured interactions can in fact be very selective. The lack of a specific structure for these interactions makes them more difficult to study in a chemically meaningful way, but one approach is statistical, i.e. simply looking at a large number of different ligands and using that to understand the chemistry of binding. Surface-bound peptide arrays are useful in this regard, and have been used as a model previously for this purpose (Wang and Woodbury, 2014). In that study, the binding of several proteins, including β-galactosidase, to all possible dipeptides, tripeptides and tetrapeptides (using seven selected amino acids) was performed and analyzed in terms of the charge characteristics, hydrophobicity, etc., of the binding interaction. The current work builds upon that study by starting with a representative subset of the tetrapeptides characterized previously and either extending them by adding all possible combinations of one, two and three amino acids, or by concatenating 57 of the previously characterized tetrapeptides to each other in all possible combinations (including order). The extended and concatenated libraries were analyzed by binding either labeled β-galactosidase to them or by binding a mixture of 10 different labeled proteins of various sizes, hydrophobicities and charge characteristics to the peptide arrays. By comparing the binding signals from the tetrapeptides or amino acid extensions alone to the binding signals from the complete extended or concatenated sequences, it was possible to evaluate the extent to which affinity and specificity of the whole sequence depends on the subsequences that make it up. The conclusion is that while joining two component sequences together can either greatly increase or decrease overall binding and specificity (relative to the component sequences alone), the contribution to the binding affinity and specificity of the individual binding components is strongly dependent on their position in the peptide; component sequences that bind strongly at the C-terminus of the peptide do not necessarily add substantially to binding and specificity when placed at the N-terminus.
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Affiliation(s)
- Wei Wang
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-5001, USA; The Center for Innovations in Medicine, The Biodesign Institute at Arizona State University, 1001 S McAllister Ave., Tempe, AZ 85287-5001, USA
| | - Neal W Woodbury
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-5001, USA; The Center for Innovations in Medicine, The Biodesign Institute at Arizona State University, 1001 S McAllister Ave., Tempe, AZ 85287-5001, USA.
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13
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McElvaney OJ, Bella AME, McElvaney NG. α-1 antitrypsin deficiency: current and future treatment options. Expert Opin Orphan Drugs 2014. [DOI: 10.1517/21678707.2015.997208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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14
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Turner AM. Alpha-1 antitrypsin deficiency: new developments in augmentation and other therapies. BioDrugs 2014; 27:547-58. [PMID: 23771682 DOI: 10.1007/s40259-013-0042-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alpha 1 antitrypsin deficiency (AATD) is a rare cause of chronic obstructive pulmonary disease. The lung disease is thought to be caused primarily by a lack of effective protection against the harmful effects of neutrophil elastase due to the low AAT levels in the lung. Patients may also develop liver disease due to polymerisation of AAT within hepatocytes. Consequently there has been much research over the years into AAT augmentation therapy in patients with lung disease, initially intravenously, and more recently in inhaled forms. This review article will discuss the role of augmentation therapy in AATD and the current status of recombinant AAT. The potential for other therapeutic strategies, such as blocking polymer formation, enhancing autophagy, gene therapy and stem cell-based treatment, will also be discussed more briefly.
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Affiliation(s)
- Alice M Turner
- QEHB Research Labs, University of Birmingham, Mindelsohn Way, Birmingham, B15 2WB, UK,
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15
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Therapeutic targeting of misfolding and conformational change in α1-antitrypsin deficiency. Future Med Chem 2014; 6:1047-65. [DOI: 10.4155/fmc.14.58] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Misfolding and conformational diseases are increasing in prominence and prevalence. Both misfolding and ‘postfolding’ conformational mechanisms can contribute to pathogenesis and can coexist. The different contexts of folding and native state behavior may have implications for the development of therapeutic strategies. α1-antitrypsin deficiency illustrates how these issues can be addressed with therapeutic approaches to rescue folding, ameliorate downstream consequences of aberrant polymerization and/or maintain physiological function. Small-molecule strategies have successfully targeted structural features of the native conformer. Recent developments include the capability to follow solution behavior of α1-antitrypsin in the context of disease mutations and interactions with drug-like compounds. Moreover, preclinical studies in cells and organisms support the potential of manipulating cellular response repertoires to process misfolded and polymer states.
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16
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Chang YP, Chu YH. Mixture-based combinatorial libraries from small individual peptide libraries: a case study on α1-antitrypsin deficiency. Molecules 2014; 19:6330-48. [PMID: 24840902 PMCID: PMC6271437 DOI: 10.3390/molecules19056330] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/12/2014] [Accepted: 05/13/2014] [Indexed: 12/12/2022] Open
Abstract
The design, synthesis and screening of diversity-oriented peptide libraries using a "libraries from libraries" strategy for the development of inhibitors of α1-antitrypsin deficiency are described. The major buttress of the biochemical approach presented here is the use of well-established solid-phase split-and-mix method for the generation of mixture-based libraries. The combinatorial technique iterative deconvolution was employed for library screening. While molecular diversity is the general consideration of combinatorial libraries, exquisite design through systematic screening of small individual libraries is a prerequisite for effective library screening and can avoid potential problems in some cases. This review will also illustrate how large peptide libraries were designed, as well as how a conformation-sensitive assay was developed based on the mechanism of the conformational disease. Finally, the combinatorially selected peptide inhibitor capable of blocking abnormal protein aggregation will be characterized by biophysical, cellular and computational methods.
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Affiliation(s)
- Yi-Pin Chang
- The Forsyth Institute, 245 First Street, Cambridge, MA 02142, USA
| | - Yen-Ho Chu
- Department of Chemistry and Biochemistry, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 62102, Taiwan.
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17
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Brebner JA, Stockley RA. Recent advances in α-1-antitrypsin deficiency-related lung disease. Expert Rev Respir Med 2014; 7:213-29; quiz 230. [DOI: 10.1586/ers.13.20] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Xin D, Holzenburg A, Burgess K. Small Molecule Probes That Perturb A Protein-protein Interface In Antithrombin. Chem Sci 2014; 5:4914-4921. [PMID: 25396040 DOI: 10.1039/c4sc01295j] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Small molecule probes for perturbing protein-protein interactions (PPIs) in vitro can be useful if they cause the target proteins to undergo biomedically relevant changes to their tertiary and quaternary structures. Application of the Exploring Key Orientations (EKO) strategy (J. Am. Chem. Soc., 2013, 135, 167 - 173) to a piperidinone-piperidine chemotype 1 indicated specific derivatives were candidates to perturb a protein-protein interface in the α-antithrombin dimer; those particular derivatives of 1 were prepared and tested. In the event, most of them significantly accelerated oligomerization of monomeric α-antithrombin, which is metastable in its oligomeric state. This assertion is supported by data from gel electrophoresis (non-denaturing PAGE; throughout) and probe-induced loss of α-antithrombin's inhibitor activity in a reaction catalyzed by thrombin. Kinetics of α-antithrombin oligomerization induced by the target compounds were examined. It was found that probes with O-benzyl-protected serine side-chains are the most active catalysts in the series, and reasons for this, based on modeling experiments, are proposed. Overall, this study reveals one of the first examples of small molecules designed to act at a protein-protein interface relevant to oligomerization of a serpin (ie α-antithrombin). The relevance of this to formation of oligomeric serpin fibrils, associated with the disease states known as "serpinopathies", is discussed.
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Affiliation(s)
- Dongyue Xin
- Department of Chemistry, Texas A & M University, Box 30012, College Station, TX 77842
| | - Andreas Holzenburg
- Microscopy and Imaging Center, Department of Biology, and Department of Biochemistry & Biophysics TAMU, College Station, TX 77843-2257
| | - Kevin Burgess
- Department of Chemistry, Texas A & M University, Box 30012, College Station, TX 77842
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19
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Gooptu B, Dickens JA, Lomas DA. The molecular and cellular pathology of α₁-antitrypsin deficiency. Trends Mol Med 2013; 20:116-27. [PMID: 24374162 DOI: 10.1016/j.molmed.2013.10.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 10/28/2013] [Accepted: 10/31/2013] [Indexed: 12/30/2022]
Abstract
Since its discovery 50 years ago, α₁-antitrypsin deficiency has represented a case study in molecular medicine, with careful clinical characterisation guiding genetic, biochemical, biophysical, structural, cellular, and in vivo studies. Here we highlight the milestones in understanding the disease mechanisms and show how they have spurred the development of novel therapeutic strategies. α₁-Antitrypsin deficiency is an archetypal conformational disease. Its pathogenesis demonstrates the interplay between protein folding and quality control mechanisms, with aberrant conformational changes causing liver and lung disease through combined loss- and toxic gain-of-function effects. Moreover, α₁-antitrypsin exemplifies the ability of diverse proteins to self-associate into a range of morphologically distinct polymers, suggesting a mechanism for protein and cell evolution.
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Affiliation(s)
- Bibek Gooptu
- Division of Asthma, Allergy, and Lung Biology, King's College London, 5th Floor, Tower Wing, Guy's Hospital, London, SE1 9RT, UK; Institute of Structural and Molecular Biology/Crystallography, Department of Biological Sciences, Birkbeck College, University of London, Malet Street, London, WC1E 7HX, UK
| | - Jennifer A Dickens
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, CB2 0XY, UK
| | - David A Lomas
- Institute of Structural and Molecular Biology/Crystallography, Department of Biological Sciences, Birkbeck College, University of London, Malet Street, London, WC1E 7HX, UK; Division of Medicine, University College London, 1st Floor, Maple House, 149, Tottenham Court Road, London, W1T 7NF, UK.
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20
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Chang YP, Chu YH. Blocking formation of large protein aggregates by small peptides. Chem Commun (Camb) 2013; 49:4591-600. [DOI: 10.1039/c3cc37518h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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21
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Demkow U, van Overveld FJ. Role of elastases in the pathogenesis of chronic obstructive pulmonary disease: implications for treatment. Eur J Med Res 2011; 15 Suppl 2:27-35. [PMID: 21147616 PMCID: PMC4360323 DOI: 10.1186/2047-783x-15-s2-27] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Neutrophil elastase, metalloproteinases, and their inhibitors play an important role in the development of chronic obstructive pulmonary disease (COPD), resulting in extensive tissue damage and malfunctioning of the airways. Nearly fifty years after the protease-antiprotease imbalance hypothesis has been suggested for the cause of emphysema, it is still appealing, but it does not explain the considerable variation in the clinical expressions of emphysema. However, there are many recent research findings to support the imbalance hypothesis as will be shown in this review. Although limited, there might be openings for the treatment of the disease.
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Affiliation(s)
- Urszula Demkow
- Dept. Lab. Diagn. and Clin. Immunol., Warsaw Medical University, Warsaw, Poland.
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22
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23
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Chang YP, Mahadeva R, Patschull AO, Nobeli I, Ekeowa UI, McKay AR, Thalassinos K, Irving JA, Haq I, Nyon MP, Christodoulou J, Ordóñez A, Miranda E, Gooptu B. Targeting Serpins in High-Throughput and Structure-Based Drug Design. Methods Enzymol 2011; 501:139-75. [DOI: 10.1016/b978-0-12-385950-1.00008-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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24
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Greene CM, McElvaney NG. Z α-1 antitrypsin deficiency and the endoplasmic reticulum stress response. World J Gastrointest Pharmacol Ther 2010; 1:94-101. [PMID: 21577302 PMCID: PMC3091154 DOI: 10.4292/wjgpt.v1.i5.94] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 09/20/2010] [Accepted: 09/27/2010] [Indexed: 02/06/2023] Open
Abstract
The serine proteinase inhibitor α-1 antitrypsin (AAT) is produced principally by the liver at the rate of 2 g/d. It is secreted into the circulation and provides an antiprotease protective screen throughout the body but most importantly in the lung, where it can neutralise the activity of the serine protease neutrophil elastase. Mutations leading to deficiency in AAT are associated with liver and lung disease. The most notable is the Z AAT mutation, which encodes a misfolded variant of the AAT protein in which the glutamic acid at position 342 is replaced by a lysine. More than 95% of all individuals with AAT deficiency carry at least one Z allele. ZAAT protein is not secreted effectively and accumulates intracellularly in the endoplasmic reticulum (ER) of hepatocytes and other AAT-producing cells. This results in a loss of function associated with decreased circulating and intrapulmonary levels of AAT. However, the misfolded protein acquires a toxic gain of function that impacts on the ER. A major function of the ER is to ensure correct protein folding. ZAAT interferes with this function and promotes ER stress responses and inflammation. Here the signalling pathways activated during ER stress in response to accumulation of ZAAT are described and therapeutic strategies that can potentially relieve ER stress are discussed.
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Affiliation(s)
- Catherine M Greene
- Catherine M Greene, Noel G McElvaney, Respiratory Research Division, Department of Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland
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25
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Chang YP, Mahadeva R, Chang WSW, Lin SC, Chu YH. Small-molecule peptides inhibit Z alpha1-antitrypsin polymerization. J Cell Mol Med 2010; 13:2304-2316. [PMID: 19120695 DOI: 10.1111/j.1582-4934.2008.00608.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The Z variant of 1-antitrypsin (AT) polymerizes within the liver and gives rise to liver cirrhosis and the associated plasma deficiency leads to emphysema. In this work, a combinatorial approach based on the inhibitory mechanism of (alpha1)-AT was developed to arrest its pathogenic polymerization. One peptide, Ac-TTAI-NH(2), emerged as the most tight-binding ligand for Z (alpha1)-AT. Characterization of this tetrapeptide by gel electrophoresis and biosensor analysis revealed its markedly improved binding specificity and affinity compared with all previously reported peptide inhibitors. In addition, the peptide is not cytotoxic to lung cell lines. A model of the peptide-protein complex suggests that the peptide interacts with nearby residues by hydrogen bonds, hydrophobic interactions, and cavity-filling stabilization. The combinatorially selected peptide not only effectively blocks the polymerization but also promotes dissociation of the oligomerized (alpha1)-AT. These results are a significant step towards the potential treatment of Z (alpha1)-AT related diseases.
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Affiliation(s)
- Yi-Pin Chang
- Department of Chemistry and Biochemistry, National Chung Cheng University,Chia-Yi, Taiwan, Republic of China
| | - Ravi Mahadeva
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Wun-Shaing W Chang
- National Institute of Cancer Research, National Health Research Institutes, Zhunan, Taiwan, Republic of China
| | - Sheng-Chieh Lin
- National Institute of Cancer Research, National Health Research Institutes, Zhunan, Taiwan, Republic of China
| | - Yen-Ho Chu
- Department of Chemistry and Biochemistry, National Chung Cheng University,Chia-Yi, Taiwan, Republic of China
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26
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Zsila F. Inhibition of heat- and chemical-induced aggregation of various proteins reveals chaperone-like activity of the acute-phase component and serine protease inhibitor human alpha(1)-antitrypsin. Biochem Biophys Res Commun 2010; 393:242-7. [PMID: 20117085 DOI: 10.1016/j.bbrc.2010.01.110] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Accepted: 01/27/2010] [Indexed: 10/19/2022]
Abstract
In vitro chaperone-like activity of the serpin family member and plasma acute-phase component human alpha(1)-antitrypsin (AAT) has been shown for the first time. Results of light-scattering experiments demonstrated that AAT efficiently inhibits both heat- and chemical-induced aggregation of various test proteins including alcohol dehydrogenase, aldolase, carbonic anhydrase, catalase, citrate synthase, enolase, glutathione S-transferase, l-lactate dehydrogenase, and beta(L)-crystallin. The results suggest that the unique metastable serpin architecture enables dual function, protease inhibiton as well as chaperone activity and highlight the serpin superfamily as a possible source of additional intra- and extracellular chaperones (e.g. alpha(1)-antichymotrypsin). The present finding is surprising in the light of the well-known role of mutated forms of AAT and other serpins in the pathogenesis of diseases called serpinopathies that featured with aberrant conformational transitions and consequent self-aggregation of serpin proteins.
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Affiliation(s)
- Ferenc Zsila
- Department of Molecular Pharmacology, Institute of Biomolecular Chemistry, Chemical Research Center, Budapest, Pusztaszeri út, Hungary.
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27
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Interactions of alpha1-proteinase inhibitor with small ligands of therapeutic potential: binding with retinoic acid. Amino Acids 2009; 38:1011-20. [PMID: 19495939 DOI: 10.1007/s00726-009-0309-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 05/15/2009] [Indexed: 10/20/2022]
Abstract
Human alpha(1)-proteinase inhibitor (alpha(1)-PI), also known as alpha(1)-antitrypsin, is the most abundant plasma serine protease inhibitor (serpin). It is best recognized for inhibition of neutrophil elastase. The alpha(1)-PI interactions with non-protease ligands were investigated mainly in regards to those molecules that may block the aggregation of alpha(1)-PI Z mutant. The objective of this study was to evaluate the potential of alpha(1)-PI to bind small non-peptide ligands of pharmaceutical interest that may attain additional properties to currently available alpha(1)-PI therapeutic preparations. Among putative ligands of bio-medical interest examined in this study, all-trans retinoic acid (RA) was selected due to its recently proposed roles in the lungs, and as an efficient optical probe. The results of this study, including absorption spectroscopy data, fluorescence quenching and the protein-induced chirality of the visible circular dichroism strongly suggest that alpha(1)-PI does bind RA in vitro to non-covalent complexes of up to two moles of RA per one mole of the protein. To our knowledge, this is the first report that provides experimental evidence of the alpha(1)-PI potential towards bi-functional drugs via a combination with RA, or potentially other molecules of pharmaceutical interest, that ultimately, may enhance currently available alpha(1)-PI therapies.
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α1-Antitrypsin deficiency, chronic obstructive pulmonary disease and the serpinopathies. Clin Sci (Lond) 2009; 116:837-50. [DOI: 10.1042/cs20080484] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
α1-Antitrypsin is the prototypical member of the serine proteinase inhibitor or serpin superfamily of proteins. The family includes α1-antichymotrypsin, C1 inhibitor, antithrombin and neuroserpin, which are all linked by a common molecular structure and the same suicidal mechanism for inhibiting their target enzymes. Point mutations result in an aberrant conformational transition and the formation of polymers that are retained within the cell of synthesis. The intracellular accumulation of polymers of mutant α1-antitrypsin and neuroserpin results in a toxic gain-of-function phenotype associated with cirrhosis and dementia respectively. The lack of important inhibitors results in overactivity of proteolytic cascades and diseases such as COPD (chronic obstructive pulmonary disease) (α1-antitrypsin and α1-antichymotrypsin), thrombosis (antithrombin) and angio-oedema (C1 inhibitor). We have grouped these conditions that share the same underlying disease mechanism together as the serpinopathies. In the present review, the molecular and pathophysiological basis of α1-antitrypsin deficiency and other serpinopathies are considered, and we show how understanding this unusual mechanism of disease has resulted in the development of novel therapeutic strategies.
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Camelier AA, Winter DH, Jardim JR, Barboza CEG, Cukier A, Miravitlles M. [Alpha-1 antitrypsin deficiency: diagnosis and treatment]. J Bras Pneumol 2009; 34:514-27. [PMID: 18695797 DOI: 10.1590/s1806-37132008000700012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2007] [Accepted: 01/31/2008] [Indexed: 11/22/2022] Open
Abstract
Alpha-1 antitrypsin deficiency is a recently identified genetic disease that occurs almost as frequently as cystic fibrosis. It is caused by various mutations in the SERPINA1 gene, and has numerous clinical implications. Alpha-1 antitrypsin is mainly produced in the liver and acts as an antiprotease. Its principal function is to inactivate neutrophil elastase, preventing tissue damage. The mutation most commonly associated with the clinical disease is the Z allele, which causes polymerization and accumulation within hepatocytes. The accumulation of and the consequent reduction in the serum levels of alpha-1 antitrypsin cause, respectively, liver and lung disease, the latter occurring mainly as early emphysema, predominantly in the lung bases. Diagnosis involves detection of low serum levels of alpha-1 antitrypsin as well as phenotypic confirmation. In addition to the standard treatment of chronic obstructive pulmonary disease, specific therapy consisting of infusion of purified alpha-1 antitrypsin is currently available. The clinical efficacy of this therapy, which appears to be safe, has yet to be definitively established, and its cost-effectiveness is also a controversial issue that is rarely addressed. Despite its importance, in Brazil, there are no epidemiological data on the prevalence of the disease or the frequency of occurrence of deficiency alleles. Underdiagnosis has also been a significant limitation to the study of the disease as well as to appropriate treatment of patients. It is hoped that the creation of the Alpha One International Registry will resolve these and other important issues.
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Affiliation(s)
- Aquiles A Camelier
- Departamento de Pneumologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, BA, Brasil.
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Mallya M, Phillips RL, Saldanha SA, Gooptu B, Leigh Brown SC, Termine DJ, Shirvani AM, Wu Y, Sifers RN, Abagyan R, Lomas DA. Small molecules block the polymerization of Z alpha1-antitrypsin and increase the clearance of intracellular aggregates. J Med Chem 2007; 50:5357-63. [PMID: 17918823 PMCID: PMC2631427 DOI: 10.1021/jm070687z] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The Z mutant of alpha1-antitrypsin (Glu342Lys) causes a domain swap and the formation of intrahepatic polymers that aggregate as inclusions and predispose the homozygote to cirrhosis. We have identified an allosteric cavity that is distinct from the interface involved in polymerization for rational structure-based drug design to block polymer formation. Virtual ligand screening was performed on 1.2 million small molecules and 6 compounds were identified that reduced polymer formation in vitro. Modeling the effects of ligand binding on the cavity and re-screening the library identified an additional 10 compounds that completely blocked polymerization. The best antagonists were effective at ratios of compound to Z alpha1-antitrypsin of 2.5:1 and reduced the intracellular accumulation of Z alpha1-antitrypsin by 70% in a cell model of disease. Identifying small molecules provides a novel therapy for the treatment of liver disease associated with the Z allele of alpha1-antitrypsin.
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Affiliation(s)
- Meera Mallya
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC building, Cambridge CB2 2XY, UK
| | - Russell L. Phillips
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC building, Cambridge CB2 2XY, UK
| | - S. Adrian Saldanha
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Bibek Gooptu
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC building, Cambridge CB2 2XY, UK
| | - Sarah C. Leigh Brown
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC building, Cambridge CB2 2XY, UK
| | - Daniel J. Termine
- Departments of Pathology, Molecular & Cellular Biology, and Molecular Physiology & Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - Arash M. Shirvani
- Departments of Pathology, Molecular & Cellular Biology, and Molecular Physiology & Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - Ying Wu
- Departments of Pathology, Molecular & Cellular Biology, and Molecular Physiology & Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - Richard N. Sifers
- Departments of Pathology, Molecular & Cellular Biology, and Molecular Physiology & Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
| | - Ruben Abagyan
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - David A Lomas
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC building, Cambridge CB2 2XY, UK
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31
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Abstract
Alpha1-antitrypsin deficiency is a genetic disorder which contributes to the development of chronic obstructive pulmonary disease, bronchiectasis, liver cirrhosis and panniculitis. The discovery of alpha1-antitrypsin and its function as an antiprotease led to the protease-antiprotease hypothesis, which goes some way to explaining the pathogenesis of emphysema. This article will review the clinical features of alpha1-antitrypsin deficiency, the genetic mutations known to cause it, and how they do so at a molecular level. Specific treatments for the disorder based on this knowledge will be reviewed, including alpha1-antitrypsin replacement, gene therapy and possible future therapies, such as those based on stem cells.
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Affiliation(s)
- Alice M Wood
- Department of Medical Sciences, University of Birmingham, Birmingham, UK
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Chowdhury P, Wang W, Lavender S, Bunagan MR, Klemke JW, Tang J, Saven JG, Cooperman BS, Gai F. Fluorescence correlation spectroscopic study of serpin depolymerization by computationally designed peptides. J Mol Biol 2007; 369:462-73. [PMID: 17442346 PMCID: PMC1995557 DOI: 10.1016/j.jmb.2007.03.042] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2006] [Revised: 03/09/2007] [Accepted: 03/15/2007] [Indexed: 11/20/2022]
Abstract
Members of the serine proteinase inhibitor (serpin) family play important roles in the inflammatory and coagulation cascades. Interaction of a serpin with its target proteinase induces a large conformational change, resulting in insertion of its reactive center loop (RCL) into the main body of the protein as a new strand within beta-sheet A. Intermolecular insertion of the RCL of one serpin molecule into the beta-sheet A of another leads to polymerization, a widespread phenomenon associated with a general class of diseases known as serpinopathies. Small peptides are known to modulate the polymerization process by binding within beta-sheet A. Here, we use fluorescence correlation spectroscopy (FCS) to probe the mechanism of peptide modulation of alpha(1)-antitrypsin (alpha(1)-AT) polymerization and depolymerization, and employ a statistical computationally-assisted design strategy (SCADS) to identify new tetrapeptides that modulate polymerization. Our results demonstrate that peptide-induced depolymerization takes place via a heterogeneous, multi-step process that begins with internal fragmentation of the polymer chain. One of the designed tetrapeptides is the most potent antitrypsin depolymerizer yet found.
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Affiliation(s)
- Pramit Chowdhury
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA
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Belorgey D, Hägglöf P, Karlsson-Li S, Lomas DA. Protein misfolding and the serpinopathies. Prion 2007; 1:15-20. [PMID: 19164889 DOI: 10.4161/pri.1.1.3974] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The serpins are the largest superfamily of protease inhibitors. They are found in almost all branches of life including viruses, prokaryotes and eukaryotes. They inhibit their target protease by a unique mechanism that involves a large conformational transition and the translocation of the enzyme from the upper to the lower pole of the protein. This complex mechanism, and the involvement of serpins in important biological regulatory processes, makes them prone to mutation-related diseases. For example the polymerization of mutant alpha(1)-antitrypsin leads to the accumulation of ordered polymers within the endoplasmic reticulum of hepatocytes in association with cirrhosis. An identical process in the neuron specific serpin, neuroserpin, results in the accumulation of polymers in neurons and the dementia FENIB. In both cases there is a clear correlation between the molecular instability, the rate of polymer formation and the severity of disease. A similar process underlies the hepatic retention and plasma deficiency of antithrombin, C1 inhibitor, alpha(1)-antichymotrypsin and heparin co-factor II. The common mechanism of polymerization has allowed us to group these conditions together as a novel class of disease, the serpinopathies.
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Affiliation(s)
- Didier Belorgey
- Department of Medicine, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, United Kingdom
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