1
|
Zhao XO, Melo FR, Sommerhoff CP, Paivandy A, Pejler G. Mast cell chymase suppresses functional parameters in primary human airway smooth muscle cells. Allergy 2024. [PMID: 38409848 DOI: 10.1111/all.16085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 01/29/2024] [Accepted: 02/20/2024] [Indexed: 02/28/2024]
Affiliation(s)
- Xinran O Zhao
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Fabio Rabelo Melo
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Christian P Sommerhoff
- Institute of Medical Education and Institute of Laboratory Medicine, LMU University Hospital, Munich, Germany
| | - Aida Paivandy
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Gunnar Pejler
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| |
Collapse
|
2
|
Tromsdorf N, Ullrich FTH, Rethmeier M, Sommerhoff CP, Schaschke N. E-64c-Hydrazide Based Cathepsin C Inhibitors: Optimizing the Interactions with the S1'-S2' Area. ChemMedChem 2023; 18:e202300218. [PMID: 37424408 DOI: 10.1002/cmdc.202300218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 07/02/2023] [Accepted: 07/03/2023] [Indexed: 07/11/2023]
Abstract
The zymogens of the neutrophil serine proteases elastase, proteinase 3, and cathepsin G are converted proteolytically into their pro-inflammatory active forms by the action of cathepsin C. The inhibition of this cysteine protease therefore is an interesting therapeutic approach for the treatment of inflammatory disorders with a high neutrophil burden such as COPD. Based on E-64c-hydrazide as lead structure, we have recently developed a covalently acting cathepsin C inhibitor using a n-butyl residue attached at the amine nitrogen of the hydrazide moiety to efficiently address the deep hydrophobic S2 pocket. To further optimize the affinity and selectivity profile of this inhibitor, the S1'-S2' area was now investigated by a combinatorial approach, showing that Nle-tryptamide is a ligand superior to the initially used Leu-isoamylamide. Using the neutrophil precursor line U937 as a cell culture model, this optimized inhibitor blocks the intracellular cathepsin C activity and thereby suppresses the activation of neutrophil elastase.
Collapse
Affiliation(s)
- Nora Tromsdorf
- Fakultät für Chemie, Hochschule Aalen, Beethovenstraße 1, 73430, Aalen, Germany
| | - Fabian T H Ullrich
- Institut für Didaktik und Ausbildungsforschung in der Medizin und Institut für Laboratoriumsmedizin, LMU Klinikum, LMU München, Pettenkoferstraße 8a, 80336, München, Germany
| | - Markus Rethmeier
- Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany
| | - Christian P Sommerhoff
- Institut für Didaktik und Ausbildungsforschung in der Medizin und Institut für Laboratoriumsmedizin, LMU Klinikum, LMU München, Pettenkoferstraße 8a, 80336, München, Germany
| | - Norbert Schaschke
- Fakultät für Chemie, Hochschule Aalen, Beethovenstraße 1, 73430, Aalen, Germany
| |
Collapse
|
3
|
Das N, de Almeida LGN, Derakhshani A, Young D, Mehdinejadiani K, Salo P, Rezansoff A, Jay GD, Sommerhoff CP, Schmidt TA, Krawetz R, Dufour A. Tryptase β regulation of joint lubrication and inflammation via proteoglycan-4 in osteoarthritis. Nat Commun 2023; 14:1910. [PMID: 37024468 PMCID: PMC10079686 DOI: 10.1038/s41467-023-37598-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 03/09/2023] [Indexed: 04/08/2023] Open
Abstract
PRG4 is an extracellular matrix protein that maintains homeostasis through its boundary lubricating and anti-inflammatory properties. Altered expression and function of PRG4 have been associated with joint inflammatory diseases, including osteoarthritis. Here we show that mast cell tryptase β cleaves PRG4 in a dose- and time-dependent manner, which was confirmed by silver stain gel electrophoresis and mass spectrometry. Tryptase-treated PRG4 results in a reduction of lubrication. Compared to full-length, cleaved PRG4 further activates NF-κB expression in cells overexpressing TLR2, -4, and -5. In the destabilization of the medial meniscus model of osteoarthritis in rat, tryptase β and PRG4 colocalize at the site of injury in knee cartilage and is associated with disease severity. When human primary synovial fibroblasts from male osteoarthritis patients or male healthy subjects treated with tryptase β and/or PRG4 are subjected to a quantitative shotgun proteomics and proteome changes are characterized, it further supports the role of NF-κB activation. Here we show that tryptase β as a modulator of joint lubrication in osteoarthritis via the cleavage of PRG4.
Collapse
Affiliation(s)
- Nabangshu Das
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Luiz G N de Almeida
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Afshin Derakhshani
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Daniel Young
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kobra Mehdinejadiani
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Paul Salo
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Alexander Rezansoff
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Gregory D Jay
- Department of Emergency Medicine, Warren Alpert Medical School & School of Engineering, Brown University, Providence, RI, USA
| | - Christian P Sommerhoff
- Institute of Medical Education and Institute of Laboratory Medicine, University Hospital, LMU Munich, Munich, Germany
| | - Tannin A Schmidt
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Biomedical Engineering Department, University of Connecticut Health Center, Farmington, CT, USA
| | - Roman Krawetz
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
| | - Antoine Dufour
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
- Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
| |
Collapse
|
4
|
Pejler G, Alanazi S, Grujic M, Adler J, Olsson AK, Sommerhoff CP, Rabelo Melo F. Mast Cell Tryptase Potentiates Neutrophil Extracellular Trap Formation. J Innate Immun 2021; 14:433-446. [PMID: 34937018 PMCID: PMC9485958 DOI: 10.1159/000520972] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 10/26/2021] [Indexed: 11/26/2022] Open
Abstract
Previous research has indicated an intimate functional communication between mast cells (MCs) and neutrophils during inflammatory conditions, but the nature of such communication is not fully understood. Activated neutrophils are known to release DNA-containing extracellular traps (neutrophil extracellular traps [NETs]) and, based on the known ability of tryptase to interact with negatively charged polymers, we here hypothesized that tryptase might interact with NET-contained DNA and thereby regulate NET formation. In support of this, we showed that tryptase markedly enhances NET formation in phorbol myristate acetate-activated human neutrophils. Moreover, tryptase was found to bind vividly to the NETs, to cause proteolysis of core histones and to cause a reduction in the levels of citrullinated histone-3. Secretome analysis revealed that tryptase caused increased release of numerous neutrophil granule compounds, including gelatinase, lactoferrin, and myeloperoxidase. We also show that DNA can induce the tetrameric, active organization of tryptase, suggesting that NET-contained DNA can maintain tryptase activity in the extracellular milieu. In line with such a scenario, DNA-stabilized tryptase was shown to efficiently degrade numerous pro-inflammatory compounds. Finally, we showed that tryptase is associated with NET formation in vivo in a melanoma setting and that NET formation in vivo is attenuated in mice lacking tryptase expression. Altogether, these findings reveal that NET formation can be regulated by MC tryptase, thus introducing a novel mechanism of communication between MCs and neutrophils.
Collapse
Affiliation(s)
- Gunnar Pejler
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- *Gunnar Pejler,
| | - Sultan Alanazi
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Mirjana Grujic
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jeremy Adler
- Department of Immunology, Genetics and Pathology − BioVis, Uppsala University, Uppsala, Sweden
| | - Anna-Karin Olsson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | | | - Fabio Rabelo Melo
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- **Fabio Rabelo Melo,
| |
Collapse
|
5
|
Zhao XO, Lampinen M, Rollman O, Sommerhoff CP, Paivandy A, Pejler G. Mast cell chymase affects the functional properties of primary human airway fibroblasts: implications for asthma. J Allergy Clin Immunol 2021; 149:718-727. [PMID: 34331992 DOI: 10.1016/j.jaci.2021.07.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 06/23/2021] [Accepted: 07/08/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND Mast cells have a profound impact on allergic asthma. Under such conditions, mast cells undergo degranulation, resulting in the release of exceptionally large amounts of mast cell-restricted proteases. However, the role of these proteases in asthma is only partially understood. OBJECTIVES Here we hypothesized that the mast cell proteases can influence the functionality of human lung fibroblasts. METHODS Primary human lung fibroblasts (HLFs) were treated with mast cell chymase or tryptase, followed by assessment of parameters related to fibroblast function. RESULTS HLFs underwent major morphological changes in response to chymase, showing signs of cellular contraction, but were refractory to tryptase. However, no effects of chymase on HLF viability or proliferation were seen. Chymase, but not tryptase, had a major impact on the output of extracellular matrix-associated compounds from the HLFs, including degradation of fibronectin and collagen-1, and activation of pro-matrix metalloprotease-2. Further, chymase induced the release of various chemotactic factors from HLFs. In line with this, conditioned medium from chymase-treated HLFs showed chemotactic activity on neutrophils. Transcriptome analysis revealed that chymase induced a pro-inflammatory gene transcription profile in HLFs, whereas tryptase had minimal effects. CONCLUSION Our findings reveal that chymase, but not tryptase, has a major impact on the phenotype of primary airway fibroblasts, by modifying their output of extracellular matrix components and by inducing a pro-inflammatory phenotype. CLINICAL IMPLICATION This study shows that mast cell chymase has a major impact on airway fibroblasts, thereby providing insight into how mast cells can influence the manifestations of asthma.
Collapse
Affiliation(s)
- Xinran O Zhao
- Uppsala University, Department of Medical Biochemistry and Microbiology, Uppsala, Sweden
| | - Maria Lampinen
- Uppsala University, Department of Medical Biochemistry and Microbiology, Uppsala, Sweden; Uppsala University, Department of Medical Sciences, Uppsala, Sweden
| | - Ola Rollman
- Uppsala University, Department of Medical Sciences, Uppsala, Sweden
| | | | - Aida Paivandy
- Uppsala University, Department of Medical Biochemistry and Microbiology, Uppsala, Sweden.
| | - Gunnar Pejler
- Uppsala University, Department of Medical Biochemistry and Microbiology, Uppsala, Sweden.
| |
Collapse
|
6
|
Rabelo Melo F, Santosh Martin S, Sommerhoff CP, Pejler G. Exosome-mediated uptake of mast cell tryptase into the nucleus of melanoma cells: a novel axis for regulating tumor cell proliferation and gene expression. Cell Death Dis 2019; 10:659. [PMID: 31506436 PMCID: PMC6736983 DOI: 10.1038/s41419-019-1879-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 08/12/2019] [Accepted: 08/20/2019] [Indexed: 01/08/2023]
Abstract
It is well established that mast cell accumulation accompanies most malignancies. However, the knowledge of how mast cells functionally impact on tumors is still rudimentary. Here we addressed this issue and show that mast cells have anti-proliferative activity on melanoma cells and that this effect is dependent on tryptase, a tetrameric protease stored in mast cell granules. Mechanistically, tryptase was found to be endocytosed by melanoma cells as cargo of DNA-coated exosomes released from melanoma cells, followed by transport to the nucleus. In the nucleus, tryptase executed clipping of histone 3 and degradation of Lamin B1, accompanied by extensive nuclear remodeling. Moreover, tryptase degraded hnRNP A2/B1, a protein involved in mRNA stabilization and interaction with non-coding RNAs. This was followed by downregulated expression of the oncogene EGR1 and of multiple non-coding RNAs, including oncogenic species. Altogether, these findings establish a new principle for regulation of tumor cell proliferation.
Collapse
Affiliation(s)
- Fabio Rabelo Melo
- Uppsala University, Department of Medical Biochemistry and Microbiology, Uppsala, Sweden.
| | | | | | - Gunnar Pejler
- Uppsala University, Department of Medical Biochemistry and Microbiology, Uppsala, Sweden. .,Swedish University of Agricultural Sciences, Department of Anatomy, Physiology and Biochemistry, Uppsala, Sweden.
| |
Collapse
|
7
|
Huber M, Cato ACB, Ainooson GK, Freichel M, Tsvilovskyy V, Jessberger R, Riedlinger E, Sommerhoff CP, Bischoff SC. Regulation of the pleiotropic effects of tissue-resident mast cells. J Allergy Clin Immunol 2019; 144:S31-S45. [PMID: 30772496 DOI: 10.1016/j.jaci.2019.02.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 01/29/2019] [Accepted: 02/01/2019] [Indexed: 12/18/2022]
Abstract
Mast cells (MCs), which are best known for their detrimental role in patients with allergic diseases, act in a diverse array of physiologic and pathologic functions made possible by the plurality of MC types. Their various developmental avenues and distinct sensitivity to (micro-) environmental conditions convey extensive heterogeneity, resulting in diverse functions. We briefly summarize this heterogeneity, elaborate on molecular determinants that allow MCs to communicate with their environment to fulfill their tasks, discuss the protease repertoire stored in secretory lysosomes, and consider different aspects of MC signaling. Furthermore, we describe key MC governance mechanisms (ie, the high-affinity receptor for IgE [FcεRI]), the stem cell factor receptor KIT, the IL-4 system, and both Ca2+- and phosphatase-dependent mechanisms. Finally, we focus on distinct physiologic functions, such as chemotaxis, phagocytosis, host defense, and the regulation of MC functions at the mucosal barriers of the lung, gastrointestinal tract, and skin. A deeper knowledge of the pleiotropic functions of MC mediators, as well as the molecular processes of MC regulation and communication, should enable us to promote beneficial MC traits in physiology and suppress detrimental MC functions in patients with disease.
Collapse
Affiliation(s)
- Michael Huber
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Aachen, Germany.
| | - Andrew C B Cato
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Eggenstein-Leopoldshafen, Germany
| | - George K Ainooson
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Eggenstein-Leopoldshafen, Germany
| | - Marc Freichel
- Institute of Pharmacology, Heidelberg University, Medical Faculty, Heidelberg, Germany
| | - Volodymyr Tsvilovskyy
- Institute of Pharmacology, Heidelberg University, Medical Faculty, Heidelberg, Germany
| | - Rolf Jessberger
- Institute for Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Eva Riedlinger
- Institute of Laboratory Medicine, University Hospital, LMU Munich, Munich, Germany
| | | | - Stephan C Bischoff
- Institute of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany.
| |
Collapse
|
8
|
Anderson E, Stavenhagen K, Kolarich D, Sommerhoff CP, Maurer M, Metz M. Human Mast Cell Tryptase Is a Potential Treatment for Snakebite Envenoming Across Multiple Snake Species. Front Immunol 2018; 9:1532. [PMID: 30038613 PMCID: PMC6047305 DOI: 10.3389/fimmu.2018.01532] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 06/20/2018] [Indexed: 12/16/2022] Open
Abstract
Snake envenoming is a serious and neglected public health crisis that is responsible for as many as 125,000 deaths per year, which is one of the reasons the World Health Organization has recently reinstated snakebite envenoming to its list of category A neglected tropical diseases. Here, we investigated the ability of human mast cell proteases to detoxify six venoms from a spectrum of phylogenetically distinct snakes. To this end, we developed a zebrafish model to assess effects on the toxicity of the venoms and characterized the degradation of venom proteins by mass spectrometry. All snake venoms tested were detoxified by degradation of various venom proteins by the mast cell protease tryptase β, and not by other proteases. Our data show that recombinant human tryptase β degrades and detoxifies a phylogenetically wide range of venoms, indicating that recombinant human tryptase could possibly be developed as a universal antidote to venomous snakebites.
Collapse
Affiliation(s)
- Elizabeth Anderson
- Department of Dermatology and Allergy, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Kathrin Stavenhagen
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Daniel Kolarich
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Christian P. Sommerhoff
- Institute of Laboratory Medicine, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Marcus Maurer
- Department of Dermatology and Allergy, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Martin Metz
- Department of Dermatology and Allergy, Charité – Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
9
|
|
10
|
Jank JM, Maier EM, Reiß DD, Haslbeck M, Kemter KF, Truger MS, Sommerhoff CP, Ferdinandusse S, Wanders RJ, Gersting SW, Muntau AC. The domain-specific and temperature-dependent protein misfolding phenotype of variant medium-chain acyl-CoA dehydrogenase. PLoS One 2014; 9:e93852. [PMID: 24718418 PMCID: PMC3981736 DOI: 10.1371/journal.pone.0093852] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/12/2014] [Indexed: 12/30/2022] Open
Abstract
The implementation of expanded newborn screening programs reduced mortality and morbidity in medium-chain acyl-CoA dehydrogenase deficiency (MCADD) caused by mutations in the ACADM gene. However, the disease is still potentially fatal. Missense induced MCADD is a protein misfolding disease with a molecular loss-of-function phenotype. Here we established a comprehensive experimental setup to analyze the structural consequences of eight ACADM missense mutations (p.Ala52Val, p.Tyr67His, p.Tyr158His, p.Arg206Cys, p.Asp266Gly, p.Lys329Glu, p.Arg334Lys, p.Arg413Ser) identified after newborn screening and linked the corresponding protein misfolding phenotype to the site of side-chain replacement with respect to the domain. With fever being the crucial risk factor for metabolic decompensation of patients with MCADD, special emphasis was put on the analysis of structural and functional derangements related to thermal stress. Based on protein conformation, thermal stability and kinetic stability, the molecular phenotype in MCADD depends on the structural region that is affected by missense-induced conformational changes with the central β-domain being particularly prone to structural derangement and destabilization. Since systematic classification of conformational derangements induced by ACADM mutations may be a helpful tool in assessing the clinical risk of patients, we scored the misfolding phenotype of the variants in comparison to p.Lys329Glu (K304E), the classical severe mutation, and p.Tyr67His (Y42H), discussed to be mild. Experiments assessing the impact of thermal stress revealed that mutations in the ACADM gene lower the temperature threshold at which MCAD loss-of-function occurs. Consequently, increased temperature as it occurs during intercurrent infections, significantly increases the risk of further conformational derangement and loss of function of the MCAD enzyme explaining the life-threatening clinical courses observed during fever episodes. Early and aggressive antipyretic treatment thus may be life-saving in patients suffering from MCADD.
Collapse
Affiliation(s)
- Johanna M. Jank
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Esther M. Maier
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Dunja D. Reiß
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Martin Haslbeck
- Department of Chemistry, Technical University Munich, Garching, Germany
| | - Kristina F. Kemter
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Marietta S. Truger
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
| | | | - Sacha Ferdinandusse
- Departments of Laboratory Medicine and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, Emma Children's Hospital, University of Amsterdam, Amsterdam, The Netherlands
| | - Ronald J. Wanders
- Departments of Laboratory Medicine and Pediatrics, Laboratory Genetic Metabolic Diseases, Academic Medical Center, Emma Children's Hospital, University of Amsterdam, Amsterdam, The Netherlands
| | - Søren W. Gersting
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Ania C. Muntau
- Department of Molecular Pediatrics, Dr. von Hauner Children’s Hospital, Ludwig-Maximilians-University, Munich, Germany
- * E-mail:
| |
Collapse
|
11
|
Kronski E, Fiori ME, Barbieri O, Astigiano S, Mirisola V, Killian PH, Bruno A, Pagani A, Rovera F, Pfeffer U, Sommerhoff CP, Noonan DM, Nerlich AG, Fontana L, Bachmeier BE. miR181b is induced by the chemopreventive polyphenol curcumin and inhibits breast cancer metastasis via down-regulation of the inflammatory cytokines CXCL1 and -2. Mol Oncol 2014; 8:581-95. [PMID: 24484937 DOI: 10.1016/j.molonc.2014.01.005] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 01/07/2014] [Accepted: 01/07/2014] [Indexed: 12/23/2022] Open
Abstract
Chronic inflammation is a major risk factor for the development and metastatic progression of cancer. We have previously reported that the chemopreventive polyphenol Curcumin inhibits the expression of the proinflammatory cytokines CXCL1 and -2 leading to diminished formation of breast and prostate cancer metastases. In the present study, we have analyzed the effects of Curcumin on miRNA expression and its correlation to the anti-tumorigenic properties of this natural occurring polyphenol. Using microarray miRNA expression analyses, we show here that Curcumin modulates the expression of a series of miRNAs, including miR181b, in metastatic breast cancer cells. Interestingly, we found that miR181b down-modulates CXCL1 and -2 through a direct binding to their 3'-UTR. Overexpression or inhibition of miR181b in metastatic breast cancer cells has a significant impact on CXCL1 and -2 and is required for the effect of Curcumin on these two cytokines. miR181b also mediates the effects of Curcumin on inhibition of proliferation and invasion as well as induction of apoptosis. Importantly, over-expression of miR181b in metastatic breast cancer cells inhibits metastasis formation in vivo in immunodeficient mice. Finally, we demonstrated that Curcumin up-regulates miR181b and down-regulates CXCL1 and -2 in cells isolated from several primary human breast cancers. Taken together, these data show that Curcumin provides a simple bridge to bring metastamir modulation into the clinic, placing it in a primary and tertiary preventive, as well as a therapeutic, setting.
Collapse
Affiliation(s)
- Emanuel Kronski
- Institute of Laboratory Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Micol E Fiori
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Ottavia Barbieri
- Department of Experimental Medicine, University of Genoa, Genoa, Italy; Embryogenesis and Tumorigenesis in Animal Models, IRCCS AOU San Martino-IST National Cancer Research Institute, Genoa, Italy
| | | | - Valentina Mirisola
- Integrated Molecular Pathology, IRCCS AOU San Martino-IST National Cancer Research Institute, Genoa, Italy
| | - Peter H Killian
- Institute of Laboratory Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Antonino Bruno
- Scientific and Technologic Pole, Fondazione Onlus MultiMedica, Milan, Italy
| | - Arianna Pagani
- Scientific and Technologic Pole, Fondazione Onlus MultiMedica, Milan, Italy
| | - Francesca Rovera
- Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy
| | - Ulrich Pfeffer
- Integrated Molecular Pathology, IRCCS AOU San Martino-IST National Cancer Research Institute, Genoa, Italy
| | | | - Douglas M Noonan
- Scientific and Technologic Pole, Fondazione Onlus MultiMedica, Milan, Italy; Department of Biotechnologies and Life Sciences, University of Insubria, Varese, Italy
| | - Andreas G Nerlich
- Institute of Pathology, Academic Hospital Munich-Bogenhausen, Munich, Germany
| | - Laura Fontana
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Beatrice E Bachmeier
- Institute of Laboratory Medicine, Ludwig-Maximilians-University, Munich, Germany.
| |
Collapse
|
12
|
Radzey H, Rethmeier M, Klimpel D, Grundhuber M, Sommerhoff CP, Schaschke N. E-64c-hydrazide: a lead structure for the development of irreversible cathepsin C inhibitors. ChemMedChem 2013; 8:1314-21. [PMID: 23780739 DOI: 10.1002/cmdc.201300093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Indexed: 12/18/2022]
Abstract
Cathepsin C is a papain-like cysteine protease with dipeptidyl aminopeptidase activity that is thought to activate various granule-associated serine proteases. Its exopeptidase activity is structurally explained by the so-called exclusion domain, which blocks the active-site cleft beyond the S2 site and, with its Asp 1 residue, provides an anchoring point for the N terminus of peptide and protein substrates. Here, the hydrazide of (2S,3S)-trans-epoxysuccinyl-L-leucylamido-3-methylbutane (E-64c) (k2/Ki =140±5 M(-1) s(-1)) is demonstrated to be a lead structure for the development of irreversible cathepsin C inhibitors. The distal amino group of the hydrazide moiety addresses the acidic Asp 1 residue at the entrance of the S2 pocket by hydrogen bonding while also occupying the flat hydrophobic S1'-S2' area with its leucine-isoamylamide moiety. Furthermore, structure-activity relationship studies revealed that functionalization of this distal amino group with alkyl residues can be used to occupy the conserved hydrophobic S2 pocket. In particular, the n-butyl derivative was identified as the most potent inhibitor of the series (k2/Ki =56 000±1700 M(-1) s(-1)).
Collapse
Affiliation(s)
- Hanna Radzey
- Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | | | | | | | | | | |
Collapse
|
13
|
Sommerhoff CP, Fritz H. Highlight: 29 th Winter School on Proteinases and Their Inhibitors. Biol Chem 2013; 393:1363. [PMID: 23667898 DOI: 10.1515/hsz-2012-0306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
No abstract available.
Collapse
|
14
|
Quimbar P, Malik U, Sommerhoff CP, Kaas Q, Chan LY, Huang YH, Grundhuber M, Dunse K, Craik DJ, Anderson MA, Daly NL. High-affinity cyclic peptide matriptase inhibitors. J Biol Chem 2013; 288:13885-96. [PMID: 23548907 DOI: 10.1074/jbc.m113.460030] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Sunflower trypsin inhibitor-1 (SFTI-1) and Momordica cochinchinensis trypsin inhibitor-II (MCoTI-II) are potent protease inhibitors comprising a cyclic backbone. RESULTS Elucidation of structure-activity relationships for SFTI-1 and MCoTI-II was used to design inhibitors with enhanced inhibitory activity. CONCLUSION An analog of MCoTI-II is one of the most potent inhibitors of matriptase. SIGNIFICANCE These results provide a solid basis for the design of selective peptide inhibitors of matriptase with therapeutic potential. The type II transmembrane serine protease matriptase is a key activator of multiple signaling pathways associated with cell proliferation and modification of the extracellular matrix. Deregulated matriptase activity correlates with a number of diseases, including cancer and hence highly selective matriptase inhibitors may have therapeutic potential. The plant-derived cyclic peptide, sunflower trypsin inhibitor-1 (SFTI-1), is a promising drug scaffold with potent matriptase inhibitory activity. In the current study we have analyzed the structure-activity relationships of SFTI-1 and Momordica cochinchinensis trypsin inhibitor-II (MCoTI-II), a structurally divergent trypsin inhibitor from Momordica cochinchinensis that also contains a cyclic backbone. We show that MCoTI-II is a significantly more potent matriptase inhibitor than SFTI-1 and that all alanine mutants of both peptides, generated using positional scanning mutagenesis, have decreased trypsin affinity, whereas several mutations either maintain or result in enhanced matriptase inhibitory activity. These intriguing results were used to design one of the most potent matriptase inhibitors known to date with a 290 pm equilibrium dissociation constant, and provide the first indication on how to modulate affinity for matriptase over trypsin in cyclic peptides. This information might be useful for the design of more selective and therapeutically relevant inhibitors of matriptase.
Collapse
Affiliation(s)
- Pedro Quimbar
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Killian PH, Kronski E, Michalik KM, Barbieri O, Astigiano S, Sommerhoff CP, Pfeffer U, Nerlich AG, Bachmeier BE. Curcumin inhibits prostate cancer metastasis in vivo by targeting the inflammatory cytokines CXCL1 and -2. Carcinogenesis 2012; 33:2507-19. [DOI: 10.1093/carcin/bgs312] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
|
16
|
Becker BF, Fischer J, Hartmann H, Chen CC, Sommerhoff CP, Tschoep J, Conzen PC, Annecke T. Inosine, not adenosine, initiates endothelial glycocalyx degradation in cardiac ischemia and hypoxia. Nucleosides Nucleotides Nucleic Acids 2012; 30:1161-7. [PMID: 22132971 DOI: 10.1080/15257770.2011.605089] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ischemia/reperfusion and hypoxia/reoxygenation of the heart both induce shedding of the coronary endothelial glycocalyx. The processes leading from an oxygen deficit to shedding are unknown. An involvement of resident perivascular cardiac mast cells has been proposed. We hypothesized that either adenosine or inosine or both, generated by nucleotide catabolism, attain the concentrations in the interstitial space sufficient to stimulate A3 receptors of mast cells during both myocardial ischemia/reperfusion and hypoxia/reoxygenation. Isolated hearts of guinea pigs were subjected to either normoxic perfusion (hemoglobin-free Krebs-Henseleit buffer equilibrated with 95% oxygen), 20 minutes hypoxic perfusion (buffer equilibrated with 21% oxygen) followed by 20 minutes reoxygenation, or 20 minutes stopped-flow ischemia followed by 20 minutes normoxic reperfusion (n = 7 each). Coronary venous effluent was collected separately from so-called transudate, a mixture of interstitial fluid and lymphatic fluid appearing on the epicardial surface. Adenosine and inosine were determined in both fluid compartments using high-performance liquid chromatography. Damage to the glycocalyx was evident after ischemia/reperfusion and hypoxia/reoxygenation. Adenosine concentrations rose to a level of 1 μM in coronary effluent during hypoxic perfusion, but remained one order of magnitude lower in the interstitial fluid. There was only a small rise in the level during postischemic perfusion. In contrast, inosine peaked at over 10 μM in interstitial fluid during hypoxia and also during reperfusion, while effluent levels remained relatively unchanged at lower levels. We conclude that only inosine attains levels in the interstitial fluid of hypoxic and postischemic hearts that are sufficient to explain the activation of mast cells via stimulation of A3-type receptors.
Collapse
Affiliation(s)
- B F Becker
- Walter-Brendel-Centre of Experimental Medicine, Ludwig-Maximilians-University, Munich, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Janke D, Sommerhoff CP, Schaschke N. The arginine mimicking β-amino acid β3hPhe(3-H2N-CH2) as S1 ligand in cyclotheonamide-based β-tryptase inhibitors. Bioorg Med Chem 2011; 19:7236-43. [DOI: 10.1016/j.bmc.2011.09.050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 09/09/2011] [Accepted: 09/10/2011] [Indexed: 01/01/2023]
|
18
|
Sommerhoff CP, Fritz H. Highlight: the Winter School on proteinases and their inhibitors. Biol Chem 2011. [PMID: 21972972 DOI: 10.1515/bc-2011-214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
19
|
Sommerhoff CP, Fritz H. Highlight: the Winter School on proteinases and their inhibitors. Biol Chem 2011; 392:947. [PMID: 21972972 DOI: 10.1515/bc.2011.214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
No abstract available
Collapse
|
20
|
Annecke T, Fischer J, Hartmann H, Tschoep J, Rehm M, Conzen P, Sommerhoff CP, Becker BF. Shedding of the coronary endothelial glycocalyx: effects of hypoxia/reoxygenation vs ischaemia/reperfusion. Br J Anaesth 2011; 107:679-86. [PMID: 21890663 DOI: 10.1093/bja/aer269] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Vascular endothelium is covered by a glycocalyx. Damage to the glycocalyx after systemic inflammation or ischaemia/reperfusion contributes to increased vascular permeability and leucocyte adhesion. The underlying mechanisms leading to ischaemia/reperfusion-induced glycocalyx shedding are incompletely understood, in terms of lack of oxygen, absence of flow, or return of oxygen. METHODS Isolated guinea pig hearts perfused with Krebs-Henseleit buffer at 37°C underwent 20 min of either stopped-flow ischaemia or hypoxic perfusion with subsequent reperfusion/reoxygenation (n = 6 each). Hearts perfused with normoxic buffer served as time controls. Epicardial transudate was collected to assess coronary net fluid filtration, colloid extravasation, and histamine release by mast cells. Syndecan-1 and heparan sulphate were measured in coronary effluent, together with lactate, purines, and the release of mast-cell tryptase β. Additional hearts were perfusion-fixed to visualize the glycocalyx. RESULTS Both ischaemia and hypoxia with reperfusion/reoxygenation resulted in significant increases in net fluid filtration (P < 0.05) and release of syndecan-1 and heparan sulphate in coronary effluent. These effects were already seen with the onset of hypoxic perfusion. Histamine was released during hypoxia and reoxygenation and also reperfusion, as was tryptase β, and high concentrations of adenosine (>1 µmol litre⁻¹, hypoxia group) and inosine (> 7 µmol litre⁻¹, ischaemia group) were measured in effluent (P < 0.05). Damage to the coronary glycocalyx was evident upon electron microscopy. CONCLUSIONS Both ischaemic and hypoxic hypoxia initiate glycocalyx degradation, promoting an increase in permeability. A contributing mechanism could be purine-mediated degranulation of resident mast cells, with liberated tryptase β acting as potential 'sheddase'.
Collapse
Affiliation(s)
- T Annecke
- Department of Anaesthesiology, Ludwig-Maximilians-University Munich, Munich, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Kraus S, Bunsen T, Schuster S, Cichoń MA, Tacke M, Reinheckel T, Sommerhoff CP, Jochum M, Nägler DK. Cellular senescence induced by cathepsin X downregulation. Eur J Cell Biol 2011; 90:678-86. [PMID: 21616554 DOI: 10.1016/j.ejcb.2011.03.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 02/22/2011] [Accepted: 03/30/2011] [Indexed: 11/24/2022] Open
Abstract
Cellular senescence represents a powerful tumor suppressor mechanism to prevent proliferation and invasion of malignant cells. Since tumor cells as well as primary fibroblasts lacking the lysosomal cysteine-type carboxypeptidase cathepsin X exhibit a reduced invasive capacity, we hypothesized that the underlying reason may be the induction of cellular senescence. To investigate the cellular and molecular mechanisms leading to diminished migration/invasion of cathepsin X-deficient cells, we have analyzed murine embryonic fibroblasts (MEF) derived from cathepsin X-deficient mice and neonatal human dermal fibroblasts (NHDF) transfected with siRNAs targeting cathepsin X. Remarkably, both cell types exhibited a flattened and enlarged cell body, a characteristic phenotype of senescent cells. Additional evidence for accelerated senescence was obtained by detection of the common senescence marker β-galactosidase. Further examination revealed increased expression levels of senescence-associated genes such as p16, p21, p53, and caveolin in these cells along with a reduced proliferation rate. The accelerated cellular senescence induced by cathepsin X deficiency was rescued by simultaneous expression of exogenous cathepsin X. Finally, cell cycle analysis confirmed a marked reduction of the synthesis rate and prolongation of the S-phase, while susceptibility to apoptosis of cathepsin X-deficient cells remained unchanged. In conclusion, cathepsin X deficiency leads to accelerated cellular senescence and consequently to diminished cellular proliferation and migration/invasion implying a potential role of cathepsin X in bypassing cellular senescence.
Collapse
Affiliation(s)
- Steffen Kraus
- Division of Clinical Chemistry and Clinical Biochemistry, University Hospital of Surgery, Ludwig-Maximilians-University, Nussbaumstr. 20, 80336 Munich, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Gersting SW, Staudigl M, Truger MS, Messing DD, Danecka MK, Sommerhoff CP, Kemter KF, Muntau AC. Activation of phenylalanine hydroxylase induces positive cooperativity toward the natural cofactor. J Biol Chem 2010; 285:30686-97. [PMID: 20667834 PMCID: PMC2945563 DOI: 10.1074/jbc.m110.124016] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 06/29/2010] [Indexed: 11/06/2022] Open
Abstract
Protein misfolding with loss-of-function of the enzyme phenylalanine hydroxylase (PAH) is the molecular basis of phenylketonuria in many individuals carrying missense mutations in the PAH gene. PAH is complexly regulated by its substrate L-Phenylalanine and its natural cofactor 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (BH(4)). Sapropterin dihydrochloride, the synthetic form of BH(4), was recently approved as the first pharmacological chaperone to correct the loss-of-function phenotype. However, current knowledge about enzyme function and regulation in the therapeutic setting is scarce. This illustrates the need for comprehensive analyses of steady state kinetics and allostery beyond single residual enzyme activity determinations to retrace the structural impact of missense mutations on the phenylalanine hydroxylating system. Current standard PAH activity assays are either indirect (NADH) or discontinuous due to substrate and product separation before detection. We developed an automated fluorescence-based continuous real-time PAH activity assay that proved to be faster and more efficient but as precise and accurate as standard methods. Wild-type PAH kinetic analyses using the new assay revealed cooperativity of activated PAH toward BH(4), a previously unknown finding. Analyses of structurally preactivated variants substantiated BH(4)-dependent cooperativity of the activated enzyme that does not rely on the presence of l-Phenylalanine but is determined by activating conformational rearrangements. These findings may have implications for an individualized therapy, as they support the hypothesis that the patient's metabolic state has a more significant effect on the interplay of the drug and the conformation and function of the target protein than currently appreciated.
Collapse
Affiliation(s)
- Søren W. Gersting
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| | - Michael Staudigl
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| | - Marietta S. Truger
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| | - Dunja D. Messing
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| | - Marta K. Danecka
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| | - Christian P. Sommerhoff
- the Department of Clinical Chemistry and Clinical Biochemistry, Surgical Clinic, Ludwig-Maximilians-University, Munich 80336, Germany
| | - Kristina F. Kemter
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| | - Ania C. Muntau
- From the Department of Molecular Pediatrics, Dr. von Hauner Children's Hospital, Munich 80337 and
| |
Collapse
|
23
|
Affiliation(s)
- Norbert Schaschke
- Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany.
| | | |
Collapse
|
24
|
Pantoja-Uceda D, Arolas JL, Aviles FX, Santoro J, Ventura S, Sommerhoff CP. Deciphering the structural basis that guides the oxidative folding of leech-derived tryptase inhibitor. J Biol Chem 2010; 284:35612-20. [PMID: 19820233 DOI: 10.1074/jbc.m109.061077] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein folding mechanisms have remained elusive mainly because of the transient nature of intermediates. Leech-derived tryptase inhibitor (LDTI) is a Kazal-type serine proteinase inhibitor that is emerging as an attractive model for folding studies. It comprises 46 amino acid residues with three disulfide bonds, with one located inside a small triple-stranded antiparallel beta-sheet and with two involved in a cystine-stabilized alpha-helix, a motif that is widely distributed in bioactive peptides. Here, we analyzed the oxidative folding and reductive unfolding of LDTI by chromatographic and disulfide analyses of acid-trapped intermediates. It folds and unfolds, respectively, via sequential oxidation and reduction of the cysteine residues that give rise to a few 1- and 2-disulfide intermediates. Species containing two native disulfide bonds predominate during LDTI folding (IIa and IIc) and unfolding (IIa and IIb). Stop/go folding experiments demonstrate that only intermediate IIa is productive and oxidizes directly into the native form. The NMR structures of acid-trapped and further isolated IIa, IIb, and IIc reveal global folds similar to that of the native protein, including a native-like canonical inhibitory loop. Enzyme kinetics shows that both IIa and IIc are inhibitory-active, which may substantially reduce proteolysis of LDTI during its folding process. The results reported show that the kinetics of the folding reaction is modulated by the specific structural properties of the intermediates and together provide insights into the interdependence of conformational folding and the assembly of native disulfides during oxidative folding.
Collapse
Affiliation(s)
- David Pantoja-Uceda
- Departamento de Espectroscopía y Estructura Molecular, Instituto de Química Física Rocasolano, Consejo Superior de Investigaciones Científicas, Serrano 119, E-28006 Madrid, Spain
| | | | | | | | | | | |
Collapse
|
25
|
Sommerhoff CP, Avrutina O, Schmoldt HU, Gabrijelcic-Geiger D, Diederichsen U, Kolmar H. Engineered cystine knot miniproteins as potent inhibitors of human mast cell tryptase beta. J Mol Biol 2009; 395:167-75. [PMID: 19852971 DOI: 10.1016/j.jmb.2009.10.028] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 10/12/2009] [Accepted: 10/15/2009] [Indexed: 11/16/2022]
Abstract
Here we report the design, chemical and recombinant synthesis, and functional properties of a series of novel inhibitors of human mast cell tryptase beta, a protease of considerable interest as a therapeutic target for the treatment of allergic asthma and inflammatory disorders. These inhibitors are derived from a linear variant of the cyclic cystine knot miniprotein MCoTI-II, originally isolated from the seeds of Momordica cochinchinensis. A synthetic cyclic miniprotein that bears additional positive charge in the loop connecting the N- and C-termini inhibits all monomers of the tryptase beta tetramer with an overall equilibrium dissociation constant K(i) of 1 nM and thus is one of the most potent proteinaceous inhibitors of tryptase beta described to date. These cystine knot miniproteins may therefore become valuable scaffolds for the design of a new generation of tryptase inhibitors.
Collapse
Affiliation(s)
- Christian P Sommerhoff
- Division of Clinical Chemistry and Clinical Biochemistry, Surgical Department, Ludwig-Maximilians-University Munich, Nussbaumstrasse 20, D-80336 Munich, Germany
| | | | | | | | | | | |
Collapse
|
26
|
Schiemann F, Brandt E, Gross R, Lindner B, Mittelstädt J, Sommerhoff CP, Schulmistrat J, Petersen F. The cathelicidin LL-37 activates human mast cells and is degraded by mast cell tryptase: counter-regulation by CXCL4. J Immunol 2009; 183:2223-31. [PMID: 19625657 DOI: 10.4049/jimmunol.0803587] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The cathelicidin LL-37 represents a potent antimicrobial and cell-stimulating agent, most abundantly expressed in peripheral organs such as lung and skin during inflammation. Because mast cells (MC) overtake prominent immunomodulatory roles in these organs, we wondered whether interactions exist between MC and LL-37. In this study, we show for the first time to our knowledge that physiological concentrations of LL-37 induce degranulation in purified human lung MC. Intriguingly, as a consequence LL-37 rapidly undergoes limited cleavage by a released protease. The enzyme was identified as beta-tryptase by inhibitor studies and by comparison to the recombinant protease. Examining the resulting LL-37 fragments for their functional activity, we found that none of the typical capacities of intact LL-37, i.e., MC degranulation, bactericidal activity, and neutralization of LPS, were retained. Conversely, we found that another inflammatory protein, the platelet-derived chemokine CXCL4, protects LL-37 from cleavage by beta-tryptase. Interestingly, CXCL4 did not act as a direct enzyme inhibitor, but destabilized active tetrameric beta-tryptase by antagonizing the heparin component required for the integrity of the tetramer. Altogether our results suggest that interaction of LL-37 and MC initiates an effective feedback loop to limit cathelicidin activity during inflammation, whereas CXCL4 may represent a physiological counter-regulator of beta-tryptase activity.
Collapse
Affiliation(s)
- Florian Schiemann
- Department of Immunology and Cell Biology, Research Center Borstel, Borstel, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Maier EM, Gersting SW, Kemter KF, Jank JM, Reindl M, Messing DD, Truger MS, Sommerhoff CP, Muntau AC. Protein misfolding is the molecular mechanism underlying MCADD identified in newborn screening. Hum Mol Genet 2009; 18:1612-23. [PMID: 19224950 PMCID: PMC2667288 DOI: 10.1093/hmg/ddp079] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Newborn screening (NBS) for medium-chain acyl-CoA dehydrogenase deficiency (MCADD) revealed a higher birth prevalence and genotypic variability than previously estimated, including numerous novel missense mutations in the ACADM gene. On average, these mutations are associated with milder biochemical phenotypes raising the question about their pathogenic relevance. In this study, we analyzed the impact of 10 ACADM mutations identified in NBS (A27V, Y42H, Y133H, R181C, R223G, D241G, K304E, R309K, I331T and R388S) on conformation, stability and enzyme kinetics of the corresponding proteins. Partial to total rescue of aggregation by co-overexpression of GroESL indicated protein misfolding. This was confirmed by accelerated thermal unfolding in all variants, as well as decreased proteolytic stability and accelerated thermal inactivation in most variants. Catalytic function varied from high residual activity to markedly decreased activity or substrate affinity. Mutations mapping to the beta-domain of the protein predisposed to severe destabilization. In silico structural analyses of the affected amino acid residues revealed involvement in functionally relevant networks. Taken together, our results substantiate the hypothesis of protein misfolding with loss-of-function being the common molecular basis in MCADD. Moreover, considerable structural alterations in all analyzed variants do not support the view that novel mutations found in NBS bear a lower risk of metabolic decompensation than that associated with mutations detected in clinically ascertained patients. Finally, the detailed insight into how ACADM missense mutations induce loss of MCAD function may provide guidance for risk assessment and counseling of patients, and in future may assist delineation of novel pharmacological strategies.
Collapse
Affiliation(s)
- Esther M Maier
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig-Maximilians-University, Munich, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Neth P, Profanter B, Geissler C, Nägler DK, Nerlich A, Sommerhoff CP, Jochum M. T-SP1: a novel serine protease-like protein predominantly expressed in testis. Biol Chem 2009; 389:1495-504. [PMID: 18844450 DOI: 10.1515/bc.2008.170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Here, we describe a novel member in the group of membrane-anchored chymotrypsin (S1)-like serine proteases, namely testis serine protease 1 (T-SP1), as it is principally expressed in testis tissue. The human T-SP1 gene encompasses 28.7 kb on the short arm of chromosome 8 and consists of seven exons. Rapid amplification of cDNA ends (RACE) experiments revealed that due to alternative splicing three different variants (T-SP1/1, -2, -3) are detectable in testis tissue displaying pronounced heterogeneity at their 3'-end. T-SP1/1 consists of an 18 amino acid signal peptide and of a 49 amino acid propeptide. The following domain with the catalytic triad of His(108), Asp(156), and Ser(250) shares sequence identities of 42% and 40% with the blood coagulation factor XI and plasma kallikrein, respectively. Only T-SP1/1 contains a hydrophobic part at the C-terminus, which provides the basis for cell membrane anchoring. Using a newly generated polyclonal anti-T-SP1 antibody, expression of the T-SP1 protein was found in the Leydig and Sertoli cells of the testis and in the epithelial cells of the ductuli efferentes. Notably, T-SP1 protein was also detectable in prostate cancer and in some ovarian cancer tissues, indicating tumor-related synthesis of T-SP1 beyond testis tissue.
Collapse
Affiliation(s)
- Peter Neth
- Division of Clinical Chemistry and Clinical Biochemistry, Department of Surgery, Ludwig Maximilians University, D-80336 Munich, Germany.
| | | | | | | | | | | | | |
Collapse
|
29
|
Sotiropoulou G, Sommerhoff CP. Highlight on Advances in Proteolysis Research. Biol Chem 2008; 389:967-9. [DOI: 10.1515/bc.2008.129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
| | - Christian P. Sommerhoff
- Division of Clinical Chemistry and Clinical Biochemistry, Surgical Department, Ludwig Maximilians University, D-80336 Munich, Germany
| |
Collapse
|
30
|
Gersting SW, Kemter KF, Staudigl M, Messing DD, Danecka MK, Lagler FB, Sommerhoff CP, Roscher AA, Muntau AC. Loss of function in phenylketonuria is caused by impaired molecular motions and conformational instability. Am J Hum Genet 2008; 83:5-17. [PMID: 18538294 PMCID: PMC2443833 DOI: 10.1016/j.ajhg.2008.05.013] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 05/09/2008] [Accepted: 05/17/2008] [Indexed: 11/21/2022] Open
Abstract
A significant share of patients with phenylalanine hydroxylase (PAH) deficiency benefits from pharmacological doses of tetrahydrobiopterin (BH(4)), the natural PAH cofactor. Phenylketonuria (PKU) is hypothesized to be a conformational disease, with loss of function due to protein destabilization, and the restoration of enzyme function that is observed in BH(4) treatment might be transmitted by correction of protein misfolding. To elucidate the molecular basis of functional impairment in PAH deficiency, we investigated the impact of ten PAH gene mutations identified in patients with BH(4)-responsiveness on enzyme kinetics, stability, and conformation of the protein (F55L, I65S, H170Q, P275L, A300S, S310Y, P314S, R408W, Y414C, Y417H). Residual enzyme activity was generally high, but allostery was disturbed in almost all cases and pointed to altered protein conformation. This was confirmed by reduced proteolytic stability, impaired tetramer assembly or aggregation, increased hydrophobicity, and accelerated thermal unfolding--with particular impact on the regulatory domain--observed in most variants. Three-dimensional modeling revealed the involvement of functionally relevant amino acid networks that may communicate misfolding throughout the protein. Our results substantiate the view that PAH deficiency is a protein-misfolding disease in which global conformational changes hinder molecular motions essential for physiological enzyme function. Thus, PKU has evolved from a model of a genetic disease that leads to severe neurological impairment to a model of a treatable protein-folding disease with loss of function.
Collapse
Affiliation(s)
- Søren W. Gersting
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| | - Kristina F. Kemter
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| | - Michael Staudigl
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| | - Dunja D. Messing
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| | - Marta K. Danecka
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| | - Florian B. Lagler
- Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Christian P. Sommerhoff
- Department of Clinical Chemistry and Clinical Biochemistry, Surgical Clinic, Ludwig Maximilians University, 80337 Munich, Germany
| | - Adelbert A. Roscher
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| | - Ania C. Muntau
- Department of Molecular Pediatrics, Children's Research Center, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, 80337 Munich, Germany
| |
Collapse
|
31
|
Vitzithum K, Lauber T, Kreutzmann P, Schulz A, Sommerhoff CP, Rösch P, Marx UC. LEKTI domain 15 is a functional Kazal-type proteinase inhibitor. Protein Expr Purif 2008; 57:45-56. [DOI: 10.1016/j.pep.2007.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Revised: 08/16/2007] [Accepted: 08/27/2007] [Indexed: 11/28/2022]
|
32
|
Arolas JL, Bronsoms S, Aviles FX, Ventura S, Sommerhoff CP. Oxidative folding of leech-derived tryptase inhibitor via native disulfide-bonded intermediates. Antioxid Redox Signal 2008; 10:77-85. [PMID: 18004973 DOI: 10.1089/ars.2007.1850] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Leech-derived tryptase inhibitor (LDTI), comprising 46 residues and a fold stabilized by three disulfide bonds, is the only protein known to inhibit human beta-tryptase with high affinity. The present work examines its oxidative folding and reductive unfolding with chromatographic and disulfide analysis of the trapped intermediates. LDTI folds and unfolds through a sequential oxidation of its cysteine residues that give rise to the accumulation of a few one- and two-disulfide intermediates. Three species containing two native disulfide bonds (IIa, IIb, and IIc) are detected in LDTI folding, but only one (IIb) seems to be productive and oxidizes into the native structure. Stop/go experiments indicate that the intermediates IIa and IIc must reduce or rearrange their disulfide bonds to reach the productive route. The acquisition of the native structure is extremely fast and efficient, probably influenced by the low levels of non-native three-disulfide (scrambled) isomers occurring along the reaction. Finally, the Cys14-Cys40 disulfide bond, buried in native LDTI and formed in IIa and IIb intermediates, appears to be a key factor for both the initiation of folding and the stability of this molecule. Together, the derived data provide a molecular basis for development of new LDTI variants with altered properties.
Collapse
Affiliation(s)
- Joan L Arolas
- Institut de Biotecnologia i Biomedicina, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | | | | | | | | |
Collapse
|
33
|
Shpacovitch VM, Seeliger S, Huber-Lang M, Balkow S, Feld M, Hollenberg MD, Sarma VJ, Ward PA, Strey A, Gerke V, Sommerhoff CP, Vergnolle N, Steinhoff M. Agonists of proteinase-activated receptor-2 affect transendothelial migration and apoptosis of human neutrophils. Exp Dermatol 2007; 16:799-806. [PMID: 17845211 DOI: 10.1111/j.1600-0625.2007.00605.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Skin is the first barrier preventing microorganism invasion in host. Wounds destroy this defense barrier and, without an appropriate care, may lead to sepsis. Neutrophil activation and immigration plays an important role at the inflammatory stage of wound healing. Neutrophils are known to express proteinase-activated receptors (PARs), which can be activated by serine proteases, also by enzymes involved in wound healing. We previously reported that PAR(2) agonists up-regulate cell adhesion molecule expression and cytokine production by human neutrophils. Here, we demonstrate that PAR(2) agonists (serine proteases as well as synthetic peptides) reduce transendothelial migration of neutrophils and prolong their life in vitro. Synthetic PAR(2) agonist also enhanced protective interferon (IFN)gamma-induced FcgammaRI expression at neutrophil cell surface. Of note, IFNgamma is a cytokine, which was used in clinical trials to reactivate human neutrophil functions during sepsis. Moreover, we observed a significant increase of PAR(2) expression on cell surface of neutrophils from septic patients as compared with healthy volunteers. Together, our results indicate that PAR(2) may be involved in the pathophysiology of neutrophil-endothelial interactions during wound healing or later during sepsis in humans, potentially by affecting neutrophil apoptosis, transendothelial migration and Fcgamma receptor-mediated phagocytosis.
Collapse
Affiliation(s)
- Victoria M Shpacovitch
- Department of Dermatology, IZKF Münster, and Boltzmann Institute for Immunobiology of the Skin, University of Münster, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
Tryptases comprise a group of trypsin-like serine proteases that are highly and selectively expressed in mast cells and to a lesser extent in basophils. Among them interest has been focused on tryptase beta, primarily because it was the first tryptase identified and because it is the predominant protease and protein component of mast cells. Subsequent studies have provided convincing evidence that tryptase beta is not only a clinically useful marker of mast cells and their activation but that it contributes to the pathogenesis of allergic inflammatory disorders, most notably asthma. The pathogenetic relevance together with the apparent lack of overt physiological functions has caused considerable interest in beta-tryptase as a potential therapeutic target. Meanwhile diverse tryptase inhibitors have been synthesized whose design in part was fostered by the structural analysis of the enzymatically active beta tryptase tetramer. Various compounds have been studied both in animal models and in man, providing proof of principle that tryptase inhibitors have therapeutic potential in asthma. Here we review the rationale to develop tryptase inhibitors and the approaches pursued, and also try to pinpoint some of the problems that hamper the development of clinically applicable drugs.
Collapse
Affiliation(s)
- C P Sommerhoff
- Abteilung Klinische Chemie und Klinische Biochemie, Klinikum der Ludwig-Maximilians-Universität, München, Germany.
| | | |
Collapse
|
35
|
Daly NL, Chen YK, Foley FM, Bansal PS, Bharathi R, Clark RJ, Sommerhoff CP, Craik DJ. The absolute structural requirement for a proline in the P3'-position of Bowman-Birk protease inhibitors is surmounted in the minimized SFTI-1 scaffold. J Biol Chem 2006; 281:23668-75. [PMID: 16766795 DOI: 10.1074/jbc.m601426200] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SFTI-1 is a small cyclic peptide from sunflower seeds that is one of the most potent trypsin inhibitors of any naturally occurring peptide and is related to the Bowman-Birk family of inhibitors (BBIs). BBIs are involved in the defense mechanisms of plants and also have potential as cancer chemopreventive agents. At only 14 amino acids in size, SFTI-1 is thought to be a highly optimized scaffold of the BBI active site region, and thus it is of interest to examine its important structural and functional features. In this study, a suite of 12 alanine mutants of SFTI-1 has been synthesized, and their structures and activities have been determined. SFTI-1 incorporates a binding loop that is clasped together with a disulfide bond and a secondary peptide loop making up the circular backbone. We show here that the secondary loop stabilizes the binding loop to the consequences of sequence variations. In particular, full-length BBIs have a conserved cis-proline that has been shown previously to be required for well defined structure and potent activity, but we show here that the SFTI-1 scaffold can accommodate mutation of this residue and still have a well defined native-like conformation and nanomolar activity in inhibiting trypsin. Among the Ala mutants, the most significant structural perturbation occurred when Asp14 was mutated, and it appears that this residue is important in stabilizing the trans peptide bond preceding Pro13 and is thus a key residue in maintaining the highly constrained structure of SFTI-1. This aspartic acid residue is thought to be involved in the cyclization mechanism associated with excision of SFTI-1 from its 58-amino acid precursor. Overall, this mutational analysis of SFTI-1 clearly defines the optimized nature of the SFTI-1 scaffold and demonstrates the importance of the secondary loop in maintaining the active conformation of the binding loop.
Collapse
Affiliation(s)
- Norelle L Daly
- Institute for Molecular Bioscience and Australian Research Council Special Research Centre for Functional and Applied Genomics, the University of Queensland, Brisbane, Queensland 4072, Australia
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Sommerhoff CP, Dunn BM, Pike RN. 4th General Meeting of the International Proteolysis Society/International Conference on Protease Inhibitors. Biol Chem 2006. [DOI: 10.1515/bc.2006.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
37
|
Iosub R, Klug J, Fijak M, Schneider E, Fröhlich S, Blumbach K, Wennemuth G, Sommerhoff CP, Steinhoff M, Meinhardt A. Development of testicular inflammation in the rat involves activation of proteinase-activated receptor-2. J Pathol 2006; 208:686-98. [PMID: 16450334 DOI: 10.1002/path.1938] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mast cells are involved in early events crucial to inflammation and autoimmune disease. Recently, proteinase-activated receptor-2 (PAR(2)), a G-protein coupled receptor important to injury responses, was shown to be activated by mast cell tryptase. To investigate whether mast cells and PAR(2) are involved in the development and/or aggravation of testicular inflammation, we studied acute and chronic inflammatory models in the rat. In normal testes, PAR(2) was detected immunohistochemically in macrophages, in peritubular cells (PTCs) and in spermatid acrosomes. In experimentally induced autoimmune orchitis (EAO), PAR(2) was strongly upregulated in macrophages and peritubular-like cells, forming concentric layers around granulomas. Mast cells increased 10-fold in number, were more widely distributed throughout the interstitial tissue, and were partially degranulated. Isolated PTCs expressed functional PAR(2), responded to PAR(2) activation by phosphorylating extracellular signal-regulated kinases 1/2 (ERK1/2) and activating protein kinase c, and increased intracellular Ca(2+) concentrations as well as monocyte chemoattractant protein-1 (MCP-1), transforming growth factor beta(2) (TGFbeta(2)), and cyclooxygenase-2 (COX-2) mRNA expression. Expression of these inflammatory mediators, together with iNOS, also increased significantly in testes 50 days after EAO. In vivo, expression of cytokines and inflammatory mediators was upregulated after injection of recombinant tryptase (MCP-1, TGFbeta(2), and COX-2) and a specific PAR(2) peptide agonist (MCP-1, TGFbeta(2)) in the testis after 5 h. These results suggest that PAR(2) activation elicited on PTCs by mast cell tryptase contributes to acute testicular inflammation and that this pathogenetic mechanism may also play a role in autoimmune orchitis.
Collapse
Affiliation(s)
- R Iosub
- Department of Anatomy and Cell Biology, Unit of Reproductive Biology, Justus Liebig University of Giessen, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Kelso EB, Lockhart JC, Hembrough T, Dunning L, Plevin R, Hollenberg MD, Sommerhoff CP, McLean JS, Ferrell WR. Therapeutic promise of proteinase-activated receptor-2 antagonism in joint inflammation. J Pharmacol Exp Ther 2005; 316:1017-24. [PMID: 16260582 DOI: 10.1124/jpet.105.093807] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Biological therapies such as tumor necrosis factor-alpha inhibitors have advanced the treatment of rheumatoid arthritis, but one-third of patients do not respond to such therapy. Furthermore, these inhibitors are now usually administered in combination with conventional disease-modifying antirheumatic drugs, suggesting they have not achieved their early promise. This study investigates a novel therapeutic target, proteinase-activated receptor (PAR)-2, in joint inflammation. Intra-articular carrageenan/kaolin (C/K) injection in mice resulted in joint swelling that was associated with synovial PAR2 up-regulation. Inhibiting receptor up-regulation using small interfering RNA technology, as confirmed by immunoblotting, substantially reduced the inflammatory response in the joint. Serine proteinase-induced joint swelling was mediated primarily via PAR2 activation, since the response to exogenous application of trypsin and tryptase was absent in PAR2 knockout mice. Furthermore, serine proteinase inhibitors were effective anti-inflammatory agents in this model. Disrupting proteolytic activation of PAR2 using antiserum (B5) directed to the receptor cleavage/activation site also attenuated C/K-induced inflammation, as did the similarly targeted PAR2 monoclonal antibody SAM-11. Finally, we report the activity of a novel small molecule PAR2 antagonist, N1-3-methylbutyryl-N4-6-aminohexanoyl-piperazine (ENMD-1068), that dose dependently attenuated joint inflammation. Our findings represent a major advance in collectively identifying PAR2 as a novel target for the future treatment of arthritis.
Collapse
Affiliation(s)
- Elizabeth B Kelso
- Center for Rheumatic Diseases, Royal Infirmary, Glasgow, Scotland, United Kingdom
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Arolas JL, Popowicz GM, Lorenzo J, Sommerhoff CP, Huber R, Aviles FX, Holak TA. The Three-Dimensional Structures of Tick Carboxypeptidase Inhibitor in Complex with A/B Carboxypeptidases Reveal a Novel Double-headed Binding Mode. J Mol Biol 2005; 350:489-98. [PMID: 15961103 DOI: 10.1016/j.jmb.2005.05.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2005] [Revised: 05/06/2005] [Accepted: 05/08/2005] [Indexed: 11/28/2022]
Abstract
The tick carboxypeptidase inhibitor (TCI) is a proteinaceous inhibitor of metallo-carboxypeptidases present in the blood-sucking tick Rhipicephalus bursa. The three-dimensional crystal structures of recombinant TCI bound to bovine carboxypeptidase A and to human carboxypeptidase B have been determined and refined at 1.7 A and at 2.0 A resolution, respectively. TCI consists of two domains that are structurally similar despite the low degree of sequence homology. The domains, each consisting of a short alpha-helix followed by a small twisted antiparallel beta-sheet, show a high level of structural homology to proteins of the beta-defensin-fold family. TCI anchors to the surface of mammalian carboxypeptidases in a double-headed manner not previously seen for carboxypeptidase inhibitors: the last three carboxy-terminal amino acid residues interact with the active site of the enzyme in a way that mimics substrate binding, and the N-terminal domain binds to an exosite distinct from the active-site groove. The structures of these complexes should prove valuable in the applications of TCI as a thrombolytic drug and as a basis for the design of novel bivalent carboxypeptidase inhibitors.
Collapse
Affiliation(s)
- Joan L Arolas
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | | | | | | | | | | | | |
Collapse
|
40
|
Büth H, Wolters B, Hartwig B, Meier-Bornheim R, Veith H, Hansen M, Sommerhoff CP, Schaschke N, Machleidt W, Fusenig NE, Boukamp P, Brix K. HaCaT keratinocytes secrete lysosomal cysteine proteinases during migration. Eur J Cell Biol 2005; 83:781-95. [PMID: 15679122 DOI: 10.1078/0171-9335-00428] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Cathepsin B, a lysosomal cysteine proteinase, was detected within vesicles of cellular protrusions forming cell-cell contact sites between keratinocytes of the stratum spinosum of human skin. This observation suggested the possibility that secretion of the protease into the pericellular spaces could be involved in the dissociation of cell-cell contacts to enable intraepidermal keratinocyte migration. To determine whether cathepsin B is indeed secreted from migrating keratinocytes, we first used subconfluent HaCaT cells as a culture model to study spontaneous keratinocyte migration. A cathepsin B-specific fluorescent affinity label proved the association of mature cathepsin B with the surfaces of HaCaT cells at the leading edges of growing cells. Second, we used scratch-wounds of confluent HaCaT monolayers as a model of induced keratinocyte migration. Cathepsin B was detected within lysosomes, i.e. vesicles within the perinuclear region of non-wounded cells. Expression of cathepsin B was up-regulated and cathepsin B-positive vesicles showed a redistribution from perinuclear to peripheral regions of keratinocytes at the wound margins within 4 h after wounding. Enzyme cytochemistry further showed that cell surface-associated cathepsin B was proteolytically active at the leading fronts of migrating keratinocytes. In addition, increased amounts of mature forms of cathepsin B were detected within the conditioned media of HaCaT cells during the first 4 h after scratch-wounding. In contrast, and as a control, the activity of the cytosolic enzyme lactate dehydrogenase was not significantly higher in media of wounded cells as compared with non-wounded controls, arguing for a specific induction of cathepsin B secretion upon wounding and migration of the cells. This was further substantiated by applying various cathepsin B-specific inhibitors after wounding. These experiments showed that the migration ability of keratinocytes was reduced due to the blockage of functional cathepsin B. Thus, our results strongly suggest that cell surface-associated cathepsin B is a protease that contributes to the remodelling of the extracellular matrix and thereby promotes keratinocyte migration during wound healing.
Collapse
Affiliation(s)
- Heiko Büth
- School of Engineering and Science, International University Bremen, Bremen, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Raymond WW, Sommerhoff CP, Caughey GH. Mastin is a gelatinolytic mast cell peptidase resembling a mini-proteasome. Arch Biochem Biophys 2005; 435:311-22. [PMID: 15708374 DOI: 10.1016/j.abb.2004.12.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Revised: 12/23/2004] [Indexed: 11/28/2022]
Abstract
Mastin is a tryptic peptidase secreted by canine mast cells. This work reveals that mastin is composed of catalytic domain singlets and disulfide-linked dimers. Monomers unite non-covalently to form tryptase-like tetramers, whereas dimers aggregate with monomers into larger clusters stabilized by hydrophobic contacts. Unlike tryptases, mastin resists inactivation by leech-derived tryptase inhibitor, indicating a smaller central cavity, as confirmed by structural models. Nonetheless, mastin is strongly gelatinolytic while not cleaving native collagen or casein, suggesting a preference for denatured proteins threaded into its central cavity. Phylogenetic analysis suggests that mammalian mastins shared more recent ancestors with soluble alpha/beta/delta tryptases than with membrane-anchored gamma-tryptases, and diverged more rapidly. We hypothesize that gelatinase activity and formation of inhibitor-resistant oligomers are ancestral characteristics shared by soluble tryptases and mastins, and that secreted mastin is a mini-proteasome-like complex that breaks down partially degraded proteins without causing bystander damage to intact, native proteins.
Collapse
Affiliation(s)
- Wilfred W Raymond
- Department of Medicine, Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA 94143-0911, USA
| | | | | |
Collapse
|
42
|
Avrutina O, Schmoldt HU, Gabrijelcic-Geiger D, Le Nguyen D, Sommerhoff CP, Diederichsen U, Kolmar H. Trypsin inhibition by macrocyclic and open-chain variants of the squash inhibitor MCoTI-II. Biol Chem 2005; 386:1301-6. [PMID: 16336125 DOI: 10.1515/bc.2005.148] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
MCoTI-I and MCoTI-II from the seeds of Momordica cochinchinensis are inhibitors of trypsin-like proteases and the only known members of the large family of squash inhibitors that are cyclic and contain an additional loop connecting the amino- and the carboxy-terminus. To investigate the contribution of macrocycle formation to biological activity, we synthesized a set of open-chain variants of MCoTI-II that lack the cyclization loop and contain various natural and non-natural amino acid substitutions in the reactive-site loop. Upon replacement of P1 lysine residue #10 within the open-chain variant of MCoTI-II by the non-natural isosteric nucleo amino acid AlaG [beta-(guanin-9-yl)-L-alanine], a conformationally restricted arginine mimetic, residual inhibitory activity was detected, albeit reduced by four orders of magnitude. While the cyclic inhibitors MCoTI-I and MCoTI-II were found to be very potent trypsin inhibitors, with picomolar inhibition constants, the open-chain variants displayed an approximately 10-fold lower affinity. These data suggest that the formation of a circular backbone in the MCoTI squash inhibitors results in enhanced affinity and therefore is a determinant of biological activity.
Collapse
Affiliation(s)
- Olga Avrutina
- Institute for Organic and Biomolecular Chemistry, Georg-August-University, D-37077 Göttingen, Germany
| | | | | | | | | | | | | |
Collapse
|
43
|
Schaschke N, Gabrijelcic-Geiger D, Dominik A, Sommerhoff CP. Affinity Chromatography of Tryptases: Design, Synthesis and Characterization of a Novel Matrix-Bound Bivalent Inhibitor. Chembiochem 2004; 6:95-103. [PMID: 15593113 DOI: 10.1002/cbic.200400217] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
beta-Tryptases are mast cell-derived serine proteases that are enzymatically active in the form of an oligomer consisting of four subunits each with trypsin-like activity. The active-site clefts, which are directed toward the central pore of the tetramer, form spatial arrays of four negatively charged S1 binding pockets. Therefore, dibasic inhibitors of appropriate geometry can bind in a bivalent fashion to neighboring subunits. We have recently identified a potent bivalent inhibitor (K(i)=18 nM), based on the bifunctional scaffold cyclo-(-D-Asp-L-Asp-) and the arginine mimetic dl-3-aminomethyl-phenylalanine methyl ester as a ligand for S1 pockets that takes advantage of the this unique tetrameric geometry. To generate an affinity matrix, the bivalent ligand was modified and immobilized on a Sepharose matrix by use of the PEG derivative Jeffamine ED 900 as spacer. This matrix selectively recognizes and binds beta-tryptase from crude protein mixtures and thus is useful as a geometry-driven means of isolating and purifying human mast cell tryptases.
Collapse
Affiliation(s)
- Norbert Schaschke
- Max-Planck-Institut für Biochemie, Am Klopferspitz 18a, 82152 Martinsried, Germany.
| | | | | | | |
Collapse
|
44
|
Arolas JL, Lorenzo J, Rovira A, Castellà J, Aviles FX, Sommerhoff CP. A carboxypeptidase inhibitor from the tick Rhipicephalus bursa: isolation, cDNA cloning, recombinant expression, and characterization. J Biol Chem 2004; 280:3441-8. [PMID: 15561703 DOI: 10.1074/jbc.m411086200] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A novel proteinaceous metallo-carboxypeptidase inhibitor, named tick carboxypeptidase inhibitor (TCI), was isolated from the ixodid tick Rhipicephalus bursa and N-terminally sequenced. The complete cDNA encoding this protein was cloned from tick mRNA by reverse transcription-PCR and rapid amplification of cDNA ends techniques. The full-length TCI cDNA contains an open reading frame coding for a precursor protein of 97 amino acid residues that consists of a predicted signal peptide of 22 residues and of mature TCI, a 75-residue cysteine-rich protein (12 Cys). The deduced amino acid sequence shows no homology to other known proteins; the C terminus, however, resembles those of other protein metallo-carboxypeptidase inhibitors, suggesting a common mechanism of inhibition. Recombinant TCI expressed in Escherichia coli is fully functional and inhibits carboxypeptidases of the A/B subfamily with equilibrium dissociation constants in the nanomolar range. Structural analyses by circular dichroism and nuclear magnetic resonance indicate that TCI is a protein strongly constrained by disulfide bonds, unusually stable over a wide pH range and highly resistant to denaturing conditions. As a tight binding inhibitor of plasma carboxypeptidase B, also known as thrombin-activatable fibrinolysis inhibitor, recombinant TCI stimulates fibrinolysis in vitro and thus may have potential for applications to prevent or treat thrombotic disorders.
Collapse
Affiliation(s)
- Joan L Arolas
- Institut de Biotecnologia i de Biomedicina and Departament de Sanitat i d'Anatomia Animals, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
| | | | | | | | | | | |
Collapse
|
45
|
Tidow H, Lauber T, Vitzithum K, Sommerhoff CP, Rösch P, Marx UC. The Solution Structure of a Chimeric LEKTI Domain Reveals a Chameleon Sequence. Biochemistry 2004; 43:11238-47. [PMID: 15366933 DOI: 10.1021/bi0492399] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The conversion of an alpha-helical to a beta-strand conformation and the presence of chameleon sequences are fascinating from the perspective that such structural features are implicated in the induction of amyloid-related fatal diseases. In this study, we have determined the solution structure of a chimeric domain (Dom1PI) from the multidomain Kazal-type serine proteinase inhibitor LEKTI using multidimensional NMR spectroscopy. This chimeric protein was constructed to investigate the reasons for differences in the folds of the homologous LEKTI domains 1 and 6 [Lauber, T., et al. (2003) J. Mol. Biol. 328, 205-219]. In Dom1PI, two adjacent phenylalanine residues (F28 and F29) of domain 1 were substituted with proline and isoleucine, respectively, as found in the corresponding P4' and P5' positions of domain 6. The three-dimensional structure of Dom1PI is significantly different from the structure of domain 1 and closely resembles the structure of domain 6, despite the sequence being identical to that of domain 1 except for the two substituted phenylalanine residues and being only 31% identical to the sequence of domain 6. The mutation converted a short 3(10)-helix into an extended loop conformation and parts of the long COOH-terminal alpha-helix of domain 1 into a beta-hairpin structure. The latter conformational change occurs in a sequence stretch distinct from the region containing the substituted residues. Therefore, this switch from an alpha-helical structure to a beta-hairpin structure indicates a chameleon sequence of seven residues. We conclude that the secondary structure of Dom1PI is determined not only by the local protein sequence but also by nonlocal interactions.
Collapse
Affiliation(s)
- Henning Tidow
- Lehrstuhl für Biopolymere, Universität Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | | | | | | | | | | |
Collapse
|
46
|
Shpacovitch VM, Varga G, Strey A, Gunzer M, Mooren F, Buddenkotte J, Vergnolle N, Sommerhoff CP, Grabbe S, Gerke V, Homey B, Hollenberg M, Luger TA, Steinhoff M. Agonists of proteinase-activated receptor-2 modulate human neutrophil cytokine secretion, expression of cell adhesion molecules, and migration within 3-D collagen lattices. J Leukoc Biol 2004; 76:388-98. [PMID: 15155775 DOI: 10.1189/jlb.0503221] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Proteinase-activated receptor-2 (PAR2) belongs to a novel subfamily of G-protein-coupled receptors with seven-transmembrane domains. PAR2 can be activated by serine proteases such as trypsin, mast cell tryptase, and allergic or bacterial proteases. This receptor is expressed by various cells and seems to be crucially involved during inflammation and the immune response. As previously reported, human neutrophils express functional PAR2. However, the precise physiological role of PAR2 on human neutrophils and its implication in human diseases remain unclear. We demonstrate that PAR2 agonist-stimulated human neutrophils show significantly enhanced migration in 3-D collagen lattices. PAR2 agonist stimulation also induced down-regulation of L-selectin display and up-regulation of membrane-activated complex-1 very late antigen-4 integrin expression on the neutrophil cell surface. Moreover, PAR2 stimulation results in an increased secretion of the cytokines interleukin (IL)-1beta, IL-8, and IL-6 by human neutrophils. These data indicate that PAR2 plays an important role in human neutrophil activation and may affect key neutrophil functions by regulating cell motility in the extracellular matrix, selectin shedding, and up-regulation of integrin expression and by stimulating the secretion of inflammatory mediators. Thus, PAR2 may represent a potential therapeutic target for the treatment of diseases involving activated neutrophils.
Collapse
Affiliation(s)
- V M Shpacovitch
- Department of Dermatology, University of Münster, von-Esmarch-Str. 58, 48149 Münster, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Gilles S, Zahler S, Welsch U, Sommerhoff CP, Becker BF. Release of TNF-α during myocardial reperfusion depends on oxidative stress and is prevented by mast cell stabilizers. Cardiovasc Res 2003; 60:608-16. [PMID: 14659806 DOI: 10.1016/j.cardiores.2003.08.016] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES Our study sought to elucidate the role of oxidative stress for shedding of tumor necrosis factor-alpha (TNF-alpha) and for activating TNF-alpha-converting enzyme (TACE). BACKGROUND TNF-alpha, a central inflammatory cytokine, is discussed as one of the mediators of reperfusion injury. Shedding of membrane-bound pro-TNF-alpha is thought to be largely due to TNF-alpha-converting enzyme (TACE). METHODS Release of TNF-alpha and TACE dependency were studied in isolated rat hearts and in the human mast cell line HMC-1. RESULTS In reperfused hearts, interstitial release of TNF-alpha occurred in two phases (2-10 and >45 min). It depended on the presence of oxygen during reperfusion and was attenuated by reduced glutathione. Infusion of the oxidants H(2)O(2) or HOCl elicited release in non-ischemic hearts. TNF-alpha release was inhibited in hearts treated with degranulation inhibitors ketotifen or cromoglycate, suggesting mast cells as major source for myocardial TNF-alpha. This was confirmed by tissue staining. Post-ischemic release of histamine, however, did not parallel that of TNF-alpha. Heart tissue contained mainly mature TACE. HMC-1 expressed abundant pro-TACE and cleaved the pro-TNF-alpha-peptide Ac-SPLAQAVRSSSR-NH(2). However, cleavage was nonspecific and only partly inhibited by TACE inhibitor TAPI-2 (10-100 micromol/l), while it was stimulated by H(2)O(2) and HOCl and fully blocked by the nonspecific metalloprotease inhibitor o-phenanthroline. CONCLUSIONS The mechanism underlying TNF-alpha release from post-ischemic myocardium is oxidation-dependent but largely independent of activation of TACE. Mast cell stabilizers may be useful in preventing TNF-alpha release during reperfusion.
Collapse
Affiliation(s)
- Stefanie Gilles
- Department of Physiology, University of Munich, Schillerstr. 44, 80336 Munich, Germany
| | | | | | | | | |
Collapse
|
48
|
Becker BF, Gilles S, Gonscherowski V, Gabrijelcic-Geiger D, Sommerhoff CP, Welsch U, Zahler S. Assessing experimental models in myocardial injury: Lack of activation of the proteases TACE and calpain in brief ischaemia and reperfusion. Heart Lung Circ 2003; 12:51-9. [PMID: 16352107 DOI: 10.1046/j.1444-2892.2003.00149.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Calpain inhibitors are reportedly cardioprotective. Furthermore, oxidative stress may acutely activate the sheddase tumour necrosis factor (TNF)-alpha-cleaving enzyme (TACE). The aim of this study was to examine whether myocardial reperfusion leads to activation of the proteases mu- and m-calpain, and to evaluate which cardiac cells act as a source of TNF-alpha. METHODS Isolated hearts (guinea pig) were subjected to global ischaemia (15 min) and reperfused. Calpain activity was determined by zymography. Calpastatin (inhibitor) and troponin I (substrate) were quantified by western blotting. Immunohistology of hearts and a human mast cell line (HMC-1) was used to localise expression of TNF-alpha and TACE. Shedding of TNF-alpha was assessed in Mono Mach, Jurkat-T, HMC-1 and peripheral blood leucocytes with and without oxidative stress. RESULTS Neither of the ubiquitous calpains (mu- and m-calpain) was significantly activated by brief ischaemia/reperfusion, nor were calpastatin and troponin degraded more than in extracts of control hearts. Cardiac TNF-alpha immunoreactivity was localised to mast cells. None of the tested cell lines shed TNF-alpha in response to non-toxic amounts of oxidants. However, HMC-1 cells showed poor expression of proTNF-alpha, while TACE was abundant. CONCLUSIONS Although the severity of ischaemia in the current model may have been insufficient, activation of calpain by ischaemia/reperfusion cannot be demonstrated simply in the Langendorff-mode perfused isolated heart. Mast cells are the prime source of myocardial TNF-alpha. A suitable whole-cell model remains to be found to demonstrate acute oxidative activation of TACE.
Collapse
|
49
|
Muntau AC, Röschinger W, Habich M, Demmelmair H, Hoffmann B, Sommerhoff CP, Roscher AA. Tetrahydrobiopterin as an alternative treatment for mild phenylketonuria. N Engl J Med 2002; 347:2122-32. [PMID: 12501224 DOI: 10.1056/nejmoa021654] [Citation(s) in RCA: 209] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Hyperphenylalaninemia is a common inherited metabolic disease that is due to phenylalanine hydroxylase deficiency, and at least half the affected patients have mild clinical phenotypes. Treatment with a low-phenylalanine diet represents a substantial psychosocial burden, but alternative treatments have not been effective. METHODS To explore the therapeutic efficacy of tetrahydrobiopterin, we performed a combined phenylalanine-tetrahydrobiopterin loading test and analyzed the in vivo rates of [13C]phenylalanine oxidation in 38 children with phenylalanine hydroxylase deficiency (age range, 1 day to 17 years). We assessed whether responsiveness to tetrahydrobiopterin was associated with specific genotypes, and we mapped mutations using a structural model of the phenylalanine hydroxylase monomer. RESULTS In 27 (87 percent) of 31 patients with mild hyperphenylalaninemia (10 patients) or mild phenylketonuria (21 patients), tetrahydrobiopterin significantly lowered blood phenylalanine levels. Phenylalanine oxidation was significantly enhanced in 23 of these 31 patients (74 percent). Conversely, none of the seven patients with classic phenylketonuria had a response to tetrahydrobiopterin as defined in this study. Long-term treatment with tetrahydrobiopterin in five children increased daily phenylalanine tolerance, allowing them to discontinue their restricted diets. Seven mutations (P314S, Y417H, V177M, V245A, A300S, E390G, and IVS4-5C-->G) were classified as probably associated with responsiveness to tetrahydrobiopterin, and six mutations (A403V, F39L, D415N, S310Y, R158Q, and I65T) were classified as potentially associated. Four mutations (Y414C, L48S, R261Q, and I65V) were inconsistently associated with this phenotype. Mutations connected to tetrahydrobiopterin responsiveness were predominantly in the catalytic domain of the protein and were not directly involved in cofactor binding. CONCLUSIONS Tetrahydrobiopterin responsiveness is common in patients with mild hyperphenylalaninemia phenotypes. Responsiveness cannot consistently be predicted on the basis of genotype, particularly in compound heterozygotes.
Collapse
Affiliation(s)
- Ania C Muntau
- Research Center, Department of Biochemical Genetics and Molecular Biology, Dr. von Hauner Children's Hospital, Ludwig Maximilians University, Munich, Germany
| | | | | | | | | | | | | |
Collapse
|
50
|
Lee M, Sommerhoff CP, von Eckardstein A, Zettl F, Fritz H, Kovanen PT. Mast cell tryptase degrades HDL and blocks its function as an acceptor of cellular cholesterol. Arterioscler Thromb Vasc Biol 2002; 22:2086-91. [PMID: 12482839 DOI: 10.1161/01.atv.0000041405.07367.b5] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE In human atherosclerotic lesions, degranulated mast cells are found in the vicinity of macrophage foam cells. Mast cell granules contain tryptase, a tetrameric serine protease requiring glycosaminoglycans for stabilization. No endogenous inhibitors have been described for tryptase, and the physiological functions of the enzyme are poorly understood. Here, we investigated the effects of human tryptase on the integrity of high density lipoprotein (HDL)3 and on its ability to release cholesterol from cultured mouse macrophage foam cells. METHODS AND RESULTS Incubation of HDL3 with tryptase led to degradation of its apolipoproteins. Tryptase predominantly degraded a quantitatively minor subfraction of HDL3 that is lipid poor, exhibits electrophoretic pre-beta mobility, and contains either apolipoprotein A-I or apolipoprotein A-IV as its sole apolipoprotein. Moreover, tryptase caused functional changes in HDL3 by destroying its ability to promote high-affinity efflux of cholesterol from macrophage foam cells, ie, the pre-beta-HDL-dependent component of the process. Human aortic proteoglycans increased the ability of tryptase to proteolyze HDL3, suggesting that the proteoglycan-rich extracellular matrix of the arterial intima provides an appropriate environment for the extracellular actions of tryptase. CONCLUSIONS By depleting pre-beta-HDL, mast cell tryptase may impair the initial step of reverse cholesterol transport and will then favor cellular accumulation of cholesterol during atherogenesis.
Collapse
Affiliation(s)
- Miriam Lee
- Wihuri Research Institute, Helsinki, Finland
| | | | | | | | | | | |
Collapse
|