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Huang Q, Le Y, Li S, Bian Y. Signaling pathways and potential therapeutic targets in acute respiratory distress syndrome (ARDS). Respir Res 2024; 25:30. [PMID: 38218783 PMCID: PMC10788036 DOI: 10.1186/s12931-024-02678-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 01/03/2024] [Indexed: 01/15/2024] Open
Abstract
Acute respiratory distress syndrome (ARDS) is a common condition associated with critically ill patients, characterized by bilateral chest radiographical opacities with refractory hypoxemia due to noncardiogenic pulmonary edema. Despite significant advances, the mortality of ARDS remains unacceptably high, and there are still no effective targeted pharmacotherapeutic agents. With the outbreak of coronavirus disease 19 worldwide, the mortality of ARDS has increased correspondingly. Comprehending the pathophysiology and the underlying molecular mechanisms of ARDS may thus be essential to developing effective therapeutic strategies and reducing mortality. To facilitate further understanding of its pathogenesis and exploring novel therapeutics, this review provides comprehensive information of ARDS from pathophysiology to molecular mechanisms and presents targeted therapeutics. We first describe the pathogenesis and pathophysiology of ARDS that involve dysregulated inflammation, alveolar-capillary barrier dysfunction, impaired alveolar fluid clearance and oxidative stress. Next, we summarize the molecular mechanisms and signaling pathways related to the above four aspects of ARDS pathophysiology, along with the latest research progress. Finally, we discuss the emerging therapeutic strategies that show exciting promise in ARDS, including several pharmacologic therapies, microRNA-based therapies and mesenchymal stromal cell therapies, highlighting the pathophysiological basis and the influences on signal transduction pathways for their use.
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Affiliation(s)
- Qianrui Huang
- Department of Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095, Jie Fang Avenue, Wuhan, 430030, China
- Department of Emergency Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095, Jie Fang Avenue, Wuhan, 430030, China
| | - Yue Le
- Department of Critical Care Medicine, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjia Bridge, Hunan Road, Gu Lou District, Nanjing, 210009, China
| | - Shusheng Li
- Department of Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095, Jie Fang Avenue, Wuhan, 430030, China.
- Department of Emergency Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095, Jie Fang Avenue, Wuhan, 430030, China.
| | - Yi Bian
- Department of Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095, Jie Fang Avenue, Wuhan, 430030, China.
- Department of Emergency Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095, Jie Fang Avenue, Wuhan, 430030, China.
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Costa L, Sousa E, Fernandes C. Cyclic Peptides in Pipeline: What Future for These Great Molecules? Pharmaceuticals (Basel) 2023; 16:996. [PMID: 37513908 PMCID: PMC10386233 DOI: 10.3390/ph16070996] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/06/2023] [Accepted: 07/08/2023] [Indexed: 07/30/2023] Open
Abstract
Cyclic peptides are molecules that are already used as drugs in therapies approved for various pharmacological activities, for example, as antibiotics, antifungals, anticancer, and immunosuppressants. Interest in these molecules has been growing due to the improved pharmacokinetic and pharmacodynamic properties of the cyclic structure over linear peptides and by the evolution of chemical synthesis, computational, and in vitro methods. To date, 53 cyclic peptides have been approved by different regulatory authorities, and many others are in clinical trials for a wide diversity of conditions. In this review, the potential of cyclic peptides is presented, and general aspects of their synthesis and development are discussed. Furthermore, an overview of already approved cyclic peptides is also given, and the cyclic peptides in clinical trials are summarized.
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Affiliation(s)
- Lia Costa
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal;
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal
| | - Emília Sousa
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal;
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal
| | - Carla Fernandes
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal;
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal
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Lemmens-Gruber R, Tzotzos S. The Epithelial Sodium Channel-An Underestimated Drug Target. Int J Mol Sci 2023; 24:ijms24097775. [PMID: 37175488 PMCID: PMC10178586 DOI: 10.3390/ijms24097775] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/14/2023] [Accepted: 04/15/2023] [Indexed: 05/15/2023] Open
Abstract
Epithelial sodium channels (ENaC) are part of a complex network of interacting biochemical pathways and as such are involved in several disease states. Dependent on site and type of mutation, gain- or loss-of-function generated symptoms occur which span from asymptomatic to life-threatening disorders such as Liddle syndrome, cystic fibrosis or generalized pseudohypoaldosteronism type 1. Variants of ENaC which are implicated in disease assist further understanding of their molecular mechanisms in order to create models for specific pharmacological targeting. Identification and characterization of ENaC modifiers not only furthers our basic understanding of how these regulatory processes interact, but also enables discovery of new therapeutic targets for the disease conditions caused by ENaC dysfunction. Numerous test compounds have revealed encouraging results in vitro and in animal models but less in clinical settings. The EMA- and FDA-designated orphan drug solnatide is currently being tested in phase 2 clinical trials in the setting of acute respiratory distress syndrome, and the NOX1/ NOX4 inhibitor setanaxib is undergoing clinical phase 2 and 3 trials for therapy of primary biliary cholangitis, liver stiffness, and carcinoma. The established ENaC blocker amiloride is mainly used as an add-on drug in the therapy of resistant hypertension and is being studied in ongoing clinical phase 3 and 4 trials for special applications. This review focuses on discussing some recent developments in the search for novel therapeutic agents.
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Affiliation(s)
- Rosa Lemmens-Gruber
- Department of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, University of Vienna, A-1090 Vienna, Austria
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Martin-Malpartida P, Arrastia-Casado S, Farrera-Sinfreu J, Lucas R, Fischer H, Fischer B, Eaton DC, Tzotzos S, Macias MJ. Conformational ensemble of the TNF-derived peptide solnatide in solution. Comput Struct Biotechnol J 2022; 20:2082-2090. [PMID: 35601958 PMCID: PMC9079168 DOI: 10.1016/j.csbj.2022.04.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/21/2022] [Accepted: 04/21/2022] [Indexed: 12/12/2022] Open
Abstract
Tumor necrosis factor (TNF) is a homotrimer that has two spatially distinct binding regions, three lectin-like domains (LLD) at the TIP of the protein and three basolaterally located receptor-binding sites, the latter of which are responsible for the inflammatory and cell death-inducing properties of the cytokine. Solnatide (a.k.a. TIP peptide, AP301) is a 17-mer cyclic peptide that mimics the LLD of human TNF which activates the amiloride-sensitive epithelial sodium channel (ENaC) and, as such, recapitulates the capacity of TNF to enhance alveolar fluid clearance, as demonstrated in numerous preclinical studies. TNF and solnatide interact with glycoproteins and these interactions are necessary for their trypanolytic and ENaC-activating activities. In view of the crucial role of ENaC in lung liquid clearance, solnatide is currently being evaluated as a novel therapeutic agent to treat pulmonary edema in patients with moderate-to-severe acute respiratory distress syndrome (ARDS), as well as severe COVID-19 patients with ARDS. To facilitate the description of the functional properties of solnatide in detail, as well as to further target-docking studies, we have analyzed its folding properties by NMR. In solution, solnatide populates a set of conformations characterized by a small hydrophobic core and two electrostatically charged poles. Using the structural information determined here and also that available for the ENaC protein, we propose a model to describe solnatide interaction with the C-terminal domain of the ENaCα subunit. This model may serve to guide future experiments to validate specific interactions with ENaCα and the design of new solnatide analogs with unexplored functionalities.
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Key Words
- AP301 peptide
- ARDS, Acute Respiratory Distress Syndrome
- AlphaFold applications
- Alveolar fluid clearance
- Amiloride-sensitive epithelial sodium channel
- Amphipathic helix
- ENaC
- ENaC, Amiloride-sensitive Epithelial Sodium/Channel
- HPLC, High Performance Liquid Chromatography
- HSQC, Heteronuclear Single Quantum Coherence
- LLD, Lectin-Like Domains
- MARCKS, Myristoylated Alanine-Rich C Kinase Substrate
- NMR, Nuclear Magnetic Resonance
- NOESY, Nuclear Overhauser Effect Spectroscopy
- PIP2, Phosphatidylinositol Bisphosphate
- Peptide NMR
- Pulmonary edema
- Solnatide structure
- TIP peptide
- TM, Transmembrane Regions
- TNF, Tumor Necrosis Factor
- TOCSY, Total Correlation Spectroscopy
- Tumor necrosis factor
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Affiliation(s)
- Pau Martin-Malpartida
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, Barcelona 08028, Spain
| | | | | | - Rudolf Lucas
- Vascular Biology Center, Dept of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Hendrik Fischer
- APEPTICO Forschung und Entwicklung GmbH, Mariahilferstraße 136, 1150 Vienna, Austria
| | - Bernhard Fischer
- APEPTICO Forschung und Entwicklung GmbH, Mariahilferstraße 136, 1150 Vienna, Austria
| | - Douglas C. Eaton
- Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Susan Tzotzos
- APEPTICO Forschung und Entwicklung GmbH, Mariahilferstraße 136, 1150 Vienna, Austria
| | - Maria J. Macias
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, Barcelona 08028, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, Barcelona 08010, Spain
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Lucas R, Hadizamani Y, Enkhbaatar P, Csanyi G, Caldwell RW, Hundsberger H, Sridhar S, Lever AA, Hudel M, Ash D, Ushio-Fukai M, Fukai T, Chakraborty T, Verin A, Eaton DC, Romero M, Hamacher J. Dichotomous Role of Tumor Necrosis Factor in Pulmonary Barrier Function and Alveolar Fluid Clearance. Front Physiol 2022; 12:793251. [PMID: 35264975 PMCID: PMC8899333 DOI: 10.3389/fphys.2021.793251] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 11/30/2021] [Indexed: 02/04/2023] Open
Abstract
Alveolar-capillary leak is a hallmark of the acute respiratory distress syndrome (ARDS), a potentially lethal complication of severe sepsis, trauma and pneumonia, including COVID-19. Apart from barrier dysfunction, ARDS is characterized by hyper-inflammation and impaired alveolar fluid clearance (AFC), which foster the development of pulmonary permeability edema and hamper gas exchange. Tumor Necrosis Factor (TNF) is an evolutionarily conserved pleiotropic cytokine, involved in host immune defense against pathogens and cancer. TNF exists in both membrane-bound and soluble form and its mainly -but not exclusively- pro-inflammatory and cytolytic actions are mediated by partially overlapping TNFR1 and TNFR2 binding sites situated at the interface between neighboring subunits in the homo-trimer. Whereas TNFR1 signaling can mediate hyper-inflammation and impaired barrier function and AFC in the lungs, ligand stimulation of TNFR2 can protect from ventilation-induced lung injury. Spatially distinct from the TNFR binding sites, TNF harbors within its structure a lectin-like domain that rather protects lung function in ARDS. The lectin-like domain of TNF -mimicked by the 17 residue TIP peptide- represents a physiological mediator of alveolar-capillary barrier protection. and increases AFC in both hydrostatic and permeability pulmonary edema animal models. The TIP peptide directly activates the epithelial sodium channel (ENaC) -a key mediator of fluid and blood pressure control- upon binding to its α subunit, which is also a part of the non-selective cation channel (NSC). Activity of the lectin-like domain of TNF is preserved in complexes between TNF and its soluble TNFRs and can be physiologically relevant in pneumonia. Antibody- and soluble TNFR-based therapeutic strategies show considerable success in diseases such as rheumatoid arthritis, psoriasis and inflammatory bowel disease, but their chronic use can increase susceptibility to infection. Since the lectin-like domain of TNF does not interfere with TNF's anti-bacterial actions, while exerting protective actions in the alveolar-capillary compartments, it is currently evaluated in clinical trials in ARDS and COVID-19. A more comprehensive knowledge of the precise role of the TNFR binding sites versus the lectin-like domain of TNF in lung injury, tissue hypoxia, repair and remodeling may foster the development of novel therapeutics for ARDS.
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Affiliation(s)
- Rudolf Lucas
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, United States,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States,*Correspondence: Rudolf Lucas,
| | - Yalda Hadizamani
- Lungen-und Atmungsstiftung Bern, Bern, Switzerland,Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, Bern, Switzerland
| | - Perenlei Enkhbaatar
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX, United States
| | - Gabor Csanyi
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, United States
| | - Robert W. Caldwell
- Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, United States
| | - Harald Hundsberger
- Department of Medical Biotechnology, University of Applied Sciences, Krems, Austria,Department of Dermatology, University Hospital of the Paracelsus Medical University, Salzburg, Austria
| | - Supriya Sridhar
- Vascular Biology Center, Augusta University, Augusta, GA, United States
| | - Alice Ann Lever
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Martina Hudel
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, Germany
| | - Dipankar Ash
- Vascular Biology Center, Augusta University, Augusta, GA, United States
| | - Masuko Ushio-Fukai
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Tohru Fukai
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, United States,Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, United States
| | - Trinad Chakraborty
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, Germany
| | - Alexander Verin
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Douglas C. Eaton
- Department of Medicine, School of Medicine, Emory University, Atlanta, GA, United States
| | - Maritza Romero
- Vascular Biology Center, Augusta University, Augusta, GA, United States,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, United States,Department of Anesthesiology and Perioperative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Jürg Hamacher
- Lungen-und Atmungsstiftung Bern, Bern, Switzerland,Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, Bern, Switzerland,Medical Clinic V-Pneumology, Allergology, Intensive Care Medicine, and Environmental Medicine, Faculty of Medicine, University Medical Centre of the Saarland, Saarland University, Homburg, Germany,Institute for Clinical & Experimental Surgery, Faculty of Medicine, Saarland University, Homburg, Germany,Jürg Hamacher,
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In Brief. Curr Probl Surg 2020. [DOI: 10.1016/j.cpsurg.2020.100778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Mowery NT, Terzian WTH, Nelson AC. Acute lung injury. Curr Probl Surg 2020; 57:100777. [PMID: 32505224 DOI: 10.1016/j.cpsurg.2020.100777] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 02/24/2020] [Indexed: 01/04/2023]
Affiliation(s)
- Nathan T Mowery
- Associate Professor of Surgery, Wake Forest Medical Center, Winston-Salem, NC.
| | | | - Adam C Nelson
- Acute Care Surgery Fellow, Wake Forest Medical Center, Winston-Salem, NC
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Lipopolysaccharide Inhibits Alpha Epithelial Sodium Channel Expression via MiR-124-5p in Alveolar Type 2 Epithelial Cells. BIOMED RESEARCH INTERNATIONAL 2020; 2020:8150780. [PMID: 32190682 PMCID: PMC7072113 DOI: 10.1155/2020/8150780] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 01/19/2020] [Accepted: 01/30/2020] [Indexed: 01/09/2023]
Abstract
Mesenchymal stem cells (MSCs) have been a potential strategy in the pretreatment of pulmonary diseases, while the mechanisms of MSCs-conditioned medium (MSCs-CM) involved with microRNAs on the regulation of lung ion transport are seldom reported. We investigated the role of miR-124-5p in lipopolysaccharide-involved epithelial sodium channel (ENaC) dysfunction and explored the potential target of miR-124-5p. We observed the lower expression of miR-124-5p after the administration of MSCs-CM, and the overexpression or inhibition of miR-124-5p regulated epithelial sodium channel α-subunit (α-ENaC) expression at protein levels in mouse alveolar type 2 epithelial (AT2) cells. We confirmed that α-ENaC is one of the target genes of miR-124-5p through dual luciferase assay and Ussing chamber assay revealed that miR-124-5p inhibited amiloride-sensitive currents associated with ENaC activity in intact H441 monolayers. Our results demonstrate that miR-124-5p can decrease the expression and function of α-ENaC in alveolar epithelial cells by targeting the 3'-UTR. The involvement of MSCs-CM in lipopolysaccharide-induced acute lung injury cell model could be related to the downregulation of miR-124-5p on α-ENaC, which may provide a new target for the treatment of acute lung injury.
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Challenges and perspectives in porcine model of acute lung injury using oleic acid. Pulm Pharmacol Ther 2019; 59:101837. [PMID: 31491506 DOI: 10.1016/j.pupt.2019.101837] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 08/16/2019] [Accepted: 09/02/2019] [Indexed: 11/23/2022]
Abstract
The oleic acid (OA) models of lung injury try to simulate the findings of human Acute Respiratory Distress Syndrome (ARDS). However, these models are difficult to replicate because they vary in terms of animals species, OA doses, time for establishment of lung injury, different observation periods and settings of mechanical ventilation. The objective of this study was to evaluate a protocol of administration of OA in lung injury model, challenges in its development and its effects on respiratory mechanics, hemodynamic changes, histology, gas exchange and mortality. We then submitted ten Large White pigs to acute lung injury through intravenous infusion of acid oleic in the pulmonary artery. The mortality of the model was 50%, due to an intense hemodynamic instability during OA administration, even with early use of vasoactive drugs. Three animals required additional doses of OA to achieve criteria for acute lung injury. Histology showed findings consistent with acute lung injury. However, more pulmonary edema was observed in lower segments than in upper segments of both lungs (p = 0.01). IL-6 and IL-8 were significantly increased compared to normal lungs (p < 0.05), and IL-6 showed higher levels in upper segments compared to lower segments (p = 0.03). Positive cells for Caspase 3 were present in all samples, localized mainly in respiratory epithelial cells and macrophages. In conclusion, this model shows histological findings of acute lung injury and inflammatory response similar to those of clinical ARDS, it presents high mortality, inconsistent reproducibility and hardly controlled hemodynamic instability.
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Wohlrab P, Kraft F, Tretter V, Ullrich R, Markstaller K, Klein KU. Recent advances in understanding acute respiratory distress syndrome. F1000Res 2018; 7. [PMID: 29568488 PMCID: PMC5840611 DOI: 10.12688/f1000research.11148.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/20/2018] [Indexed: 12/17/2022] Open
Abstract
Acute respiratory distress syndrome (ARDS) is characterized by acute diffuse lung injury, which results in increased pulmonary vascular permeability and loss of aerated lung tissue. This causes bilateral opacity consistent with pulmonary edema, hypoxemia, increased venous admixture, and decreased lung compliance such that patients with ARDS need supportive care in the intensive care unit to maintain oxygenation and prevent adverse outcomes. Recently, advances in understanding the underlying pathophysiology of ARDS led to new approaches in managing these patients. In this review, we want to focus on recent scientific evidence in the field of ARDS research and discuss promising new developments in the treatment of this disease.
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Affiliation(s)
- Peter Wohlrab
- Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Felix Kraft
- Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Verena Tretter
- Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Roman Ullrich
- Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Klaus Markstaller
- Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Klaus Ulrich Klein
- Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
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Ware LB. Targeting resolution of pulmonary edema in primary graft dysfunction after lung transplantation: Is inhaled AP301 the answer? J Heart Lung Transplant 2017; 37:S1053-2498(17)32114-9. [PMID: 29198870 DOI: 10.1016/j.healun.2017.11.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 11/13/2017] [Indexed: 01/11/2023] Open
Affiliation(s)
- Lorraine B Ware
- Departments of Medicine and Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee.
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Krenn K, Lucas R, Croizé A, Boehme S, Klein KU, Hermann R, Markstaller K, Ullrich R. Inhaled AP301 for treatment of pulmonary edema in mechanically ventilated patients with acute respiratory distress syndrome: a phase IIa randomized placebo-controlled trial. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2017; 21:194. [PMID: 28750677 PMCID: PMC5531100 DOI: 10.1186/s13054-017-1795-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 07/12/2017] [Indexed: 02/08/2023]
Abstract
Background High-permeability pulmonary edema is a hallmark of acute respiratory distress syndrome (ARDS) and is frequently accompanied by impaired alveolar fluid clearance (AFC). AP301 enhances AFC by activating epithelial sodium channels (ENaCs) on alveolar epithelial cells, and we investigated its effect on extravascular lung water index (EVLWI) in mechanically ventilated patients with ARDS. Methods Forty adult mechanically ventilated patients with ARDS were included in a randomized, double-blind, placebo-controlled trial for proof of concept. Patients were treated with inhaled AP301 (n = 20) or placebo (0.9% NaCl; n = 20) twice daily for 7 days. EVLWI was measured by thermodilution (PiCCO®), and treatment groups were compared using the nonparametric Mann–Whitney U test. Results AP301 inhalation was well tolerated. No differences in mean baseline-adjusted change in EVLWI from screening to day 7 were found between the AP301 and placebo group (p = 0.196). There was no difference in the PaO2/FiO2 ratio, ventilation pressures, Murray lung injury score, or 28-day mortality between the treatment groups. An exploratory subgroup analysis according to severity of illness showed reductions in EVLWI (p = 0.04) and ventilation pressures (p < 0.05) over 7 days in patients with initial sequential organ failure assessment (SOFA) scores ≥11 inhaling AP301 versus placebo, but not in patients with SOFA scores ≤10. Conclusions There was no difference in mean baseline-adjusted EVLWI between the AP301 and placebo group. An exploratory post-hoc subgroup analysis indicated reduced EVLWI in patients with SOFA scores ≥11 receiving AP301. These results suggest further confirmation in future clinical trials of inhaled AP301 for treatment of pulmonary edema in patients with ARDS. Trial registration The study was prospectively registered at clinicaltrials.gov, NCT01627613. Registered 20 June 2012. Electronic supplementary material The online version of this article (doi:10.1186/s13054-017-1795-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Katharina Krenn
- Department of Anaesthesia, Critical Care and Pain Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria
| | - Rudolf Lucas
- Vascular Biology Center, Department of Pharmacology and Toxicology and Division of Pulmonary and Critical Care Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Adrien Croizé
- Department of Anaesthesia, Critical Care and Pain Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria
| | - Stefan Boehme
- Department of Anaesthesia, Critical Care and Pain Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria
| | - Klaus Ulrich Klein
- Department of Anaesthesia, Critical Care and Pain Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria
| | | | - Klaus Markstaller
- Department of Anaesthesia, Critical Care and Pain Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria
| | - Roman Ullrich
- Department of Anaesthesia, Critical Care and Pain Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria.
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Willam A, Aufy M, Tzotzos S, El-Malazi D, Poser F, Wagner A, Unterköfler B, Gurmani D, Martan D, Iqbal SM, Fischer B, Fischer H, Pietschmann H, Czikora I, Lucas R, Lemmens-Gruber R, Shabbir W. TNF Lectin-Like Domain Restores Epithelial Sodium Channel Function in Frameshift Mutants Associated with Pseudohypoaldosteronism Type 1B. Front Immunol 2017; 8:601. [PMID: 28611771 PMCID: PMC5447021 DOI: 10.3389/fimmu.2017.00601] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 05/08/2017] [Indexed: 11/28/2022] Open
Abstract
Previous in vitro studies have indicated that tumor necrosis factor (TNF) activates amiloride-sensitive epithelial sodium channel (ENaC) current through its lectin-like (TIP) domain, since cyclic peptides mimicking the TIP domain (e.g., solnatide), showed ENaC-activating properties. In the current study, the effects of TNF and solnatide on individual ENaC subunits or ENaC carrying mutated glycosylation sites in the α-ENaC subunit were compared, revealing a similar mode of action for TNF and solnatide and corroborating the previous assumption that the lectin-like domain of TNF is the relevant molecular structure for ENaC activation. Accordingly, TNF enhanced ENaC current by increasing open probability of the glycosylated channel, position N511 in the α-ENaC subunit being identified as the most important glycosylation site. TNF significantly increased Na+ current through ENaC comprising only the pore forming subunits α or δ, was less active in ENaC comprising only β-subunits, and showed no effect on ENaC comprising γ-subunits. TNF did not increase the membrane abundance of ENaC subunits to the extent observed with solnatide. Since the α-subunit is believed to play a prominent role in the ENaC current activating effect of TNF and TIP, we investigated whether TNF and solnatide can enhance αβγ-ENaC current in α-ENaC loss-of-function frameshift mutants. The efficacy of solnatide has been already proven in pathological conditions involving ENaC in phase II clinical trials. The frameshift mutations αI68fs, αT169fs, αP197fs, αE272fs, αF435fs, αR438fs, αY447fs, αR448fs, αS452fs, and αT482fs have been reported to cause pseudohypoaldosteronism type 1B (PHA1B), a rare, life-threatening, salt-wasting disease, which hitherto has been treated only symptomatically. In a heterologous expression system, all frameshift mutants showed significantly reduced amiloride-sensitive whole-cell current compared to wild type αβγ-ENaC, whereas membrane abundance varied between mutants. Solnatide restored function in α-ENaC frameshift mutants to current density levels of wild type ENaC or higher despite their lacking a binding site for solnatide, previously located to the region between TM2 and the C-terminus of the α-subunit. TNF similarly restored current density to wild type levels in the mutant αR448fs. Activation of βγ-ENaC may contribute to this moderate current enhancement, but whatever the mechanism, experimental data indicate that solnatide could be a new strategy to treat PHA1B.
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Affiliation(s)
- Anita Willam
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria.,APEPTICO GmbH, Vienna, Austria
| | - Mohammed Aufy
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | | | - Dina El-Malazi
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Franziska Poser
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Alina Wagner
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Birgit Unterköfler
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Didja Gurmani
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - David Martan
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | | | | | | | | | - Istvan Czikora
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Rudolf Lucas
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Rosa Lemmens-Gruber
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Waheed Shabbir
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria.,APEPTICO GmbH, Vienna, Austria
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Peteranderl C, Sznajder JI, Herold S, Lecuona E. Inflammatory Responses Regulating Alveolar Ion Transport during Pulmonary Infections. Front Immunol 2017; 8:446. [PMID: 28458673 PMCID: PMC5394420 DOI: 10.3389/fimmu.2017.00446] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 03/31/2017] [Indexed: 01/13/2023] Open
Abstract
The respiratory epithelium is lined by a tightly balanced fluid layer that allows normal O2 and CO2 exchange and maintains surface tension and host defense. To maintain alveolar fluid homeostasis, both the integrity of the alveolar–capillary barrier and the expression of epithelial ion channels and pumps are necessary to establish a vectorial ion gradient. However, during pulmonary infection, auto- and/or paracrine-acting mediators induce pathophysiological changes of the alveolar–capillary barrier, altered expression of epithelial Na,K-ATPase and of epithelial ion channels including epithelial sodium channel and cystic fibrosis membrane conductance regulator, leading to the accumulation of edema and impaired alveolar fluid clearance. These mediators include classical pro-inflammatory cytokines such as TGF-β, TNF-α, interferons, or IL-1β that are released upon bacterial challenge with Streptococcus pneumoniae, Klebsiella pneumoniae, or Mycoplasma pneumoniae as well as in viral infection with influenza A virus, pathogenic coronaviruses, or respiratory syncytial virus. Moreover, the pro-apoptotic mediator TNF-related apoptosis-inducing ligand, extracellular nucleotides, or reactive oxygen species impair epithelial ion channel expression and function. Interestingly, during bacterial infection, alterations of ion transport function may serve as an additional feedback loop on the respiratory inflammatory profile, further aggravating disease progression. These changes lead to edema formation and impair edema clearance which results in suboptimal gas exchange causing hypoxemia and hypercapnia. Recent preclinical studies suggest that modulation of the alveolar–capillary fluid homeostasis could represent novel therapeutic approaches to improve outcomes in infection-induced lung injury.
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Affiliation(s)
- Christin Peteranderl
- Department of Internal Medicine II, University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Jacob I Sznajder
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Susanne Herold
- Department of Internal Medicine II, University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Emilia Lecuona
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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Solnatide Demonstrates Profound Therapeutic Activity in a Rat Model of Pulmonary Edema Induced by Acute Hypobaric Hypoxia and Exercise. Chest 2017; 151:658-667. [DOI: 10.1016/j.chest.2016.10.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 10/11/2016] [Accepted: 10/17/2016] [Indexed: 11/23/2022] Open
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Willam A, Aufy M, Tzotzos S, Evanzin H, Chytracek S, Geppert S, Fischer B, Fischer H, Pietschmann H, Czikora I, Lucas R, Lemmens-Gruber R, Shabbir W. Restoration of Epithelial Sodium Channel Function by Synthetic Peptides in Pseudohypoaldosteronism Type 1B Mutants. Front Pharmacol 2017; 8:85. [PMID: 28286482 PMCID: PMC5323398 DOI: 10.3389/fphar.2017.00085] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 02/09/2017] [Indexed: 12/20/2022] Open
Abstract
The synthetically produced cyclic peptides solnatide (a.k.a. TIP or AP301) and its congener AP318, whose molecular structures mimic the lectin-like domain of human tumor necrosis factor (TNF), have been shown to activate the epithelial sodium channel (ENaC) in various cell- and animal-based studies. Loss-of-ENaC-function leads to a rare, life-threatening, salt-wasting syndrome, pseudohypoaldosteronism type 1B (PHA1B), which presents with failure to thrive, dehydration, low blood pressure, anorexia and vomiting; hyperkalemia, hyponatremia and metabolic acidosis suggest hypoaldosteronism, but plasma aldosterone and renin activity are high. The aim of the present study was to investigate whether the ENaC-activating effect of solnatide and AP318 could rescue loss-of-function phenotype of ENaC carrying mutations at conserved amino acid positions observed to cause PHA1B. The macroscopic Na+ current of all investigated mutants was decreased compared to wild type ENaC when measured in whole-cell patch clamp experiments, and a great variation in the membrane abundance of different mutant ENaCs was observed with Western blotting experiments. However, whatever mechanism leads to loss-of-function of the studied ENaC mutations, the synthetic peptides solnatide and AP318 could restore ENaC function up to or even higher than current levels of wild type ENaC. As therapy of PHA1B is only symptomatic so far, the peptides solnatide and AP318, which directly target ENaC, are promising candidates for the treatment of the channelopathy-caused disease PHA1B.
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Affiliation(s)
- Anita Willam
- Department of Pharmacology and Toxicology, University of Vienna Vienna, Austria
| | - Mohammed Aufy
- Department of Pharmacology and Toxicology, University of Vienna Vienna, Austria
| | | | - Heinrich Evanzin
- Department of Pharmacology and Toxicology, University of Vienna Vienna, Austria
| | - Sabine Chytracek
- Department of Pharmacology and Toxicology, University of Vienna Vienna, Austria
| | - Sabrina Geppert
- Department of Pharmacology and Toxicology, University of Vienna Vienna, Austria
| | | | | | | | - Istvan Czikora
- Vascular Biology Center, Medical College of Georgia, Augusta University Augusta, GA, USA
| | - Rudolf Lucas
- Vascular Biology Center, Medical College of Georgia, Augusta University Augusta, GA, USA
| | - Rosa Lemmens-Gruber
- Department of Pharmacology and Toxicology, University of Vienna Vienna, Austria
| | - Waheed Shabbir
- Department of Pharmacology and Toxicology, University of ViennaVienna, Austria; APEPTICO GmbHVienna, Austria
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17
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Glycosylation-dependent activation of epithelial sodium channel by solnatide. Biochem Pharmacol 2015; 98:740-53. [DOI: 10.1016/j.bcp.2015.08.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/03/2015] [Indexed: 12/29/2022]
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Hartmann EK, Ziebart A, Thomas R, Liu T, Schad A, Tews M, Moosmann B, Kamuf J, Duenges B, Thal SC, David M. Inhalation therapy with the synthetic TIP-like peptide AP318 attenuates pulmonary inflammation in a porcine sepsis model. BMC Pulm Med 2015; 15:7. [PMID: 25879802 PMCID: PMC4346123 DOI: 10.1186/s12890-015-0002-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 01/19/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The lectin-like domain of TNF-α can be mimicked by synthetic TIP peptides and represents an innovative pharmacologic option to treat edematous respiratory failure. TIP inhalation was shown to reduce pulmonary edema and improve gas exchange. In addition to its edema resolution effect, TIP peptides may exert some anti-inflammatory properties. The present study therefore investigates the influence of the inhaled TIP peptide AP318 on intrapulmonary inflammatory response in a porcine model of systemic sepsis. METHODS In a randomized-blinded setting lung injury was induced in 18 pigs by lipopolysaccharide-infusion and a second hit with a short period of ventilator-induced lung stress, followed by a six-hour observation period. The animals received either two inhalations with the peptide (AP318, 2×1 mg kg(-1)) or vehicle. Post-mortem pulmonary expression of inflammatory and mechanotransduction markers were determined by real-time polymerase chain reaction (IL-1β, IL-6, TNF-α, COX-2, iNOS, amphiregulin, and tenascin-c). Furthermore, regional histopathological lung injury, edema formation and systemic inflammation were quantified. RESULTS Despite similar systemic response to lipopolysaccharide infusion in both groups, pulmonary inflammation (IL-6, TNF-α, COX-2, tenascin-c) was significantly mitigated by AP318. Furthermore, a Western blot analysis shows a significantly lower of COX-2 protein level. The present sepsis model caused minor lung edema formation and moderate gas exchange impairment. Six hours after onset pathologic scoring showed no improvement, while gas exchange parameters and pulmonary edema formation were similar in the two groups. CONCLUSION In summary, AP318 significantly attenuated intrapulmonary inflammatory response even without the presence or resolution of severe pulmonary edema in a porcine model of systemic sepsis-associated lung injury. These findings suggest an anti-inflammatory mechanism of the lectin-like domain beyond mere edema reabsorption in endotoxemic lung injury in vivo.
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Affiliation(s)
- Erik K Hartmann
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Alexander Ziebart
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Rainer Thomas
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Tanghua Liu
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Arno Schad
- Institute of Pathology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Martha Tews
- Institute of Pathobiochemistry, Medical Center of the Johannes, Gutenberg-University, Duesbergweg 6, 55128, Mainz, Germany.
| | - Bernd Moosmann
- Institute of Pathobiochemistry, Medical Center of the Johannes, Gutenberg-University, Duesbergweg 6, 55128, Mainz, Germany.
| | - Jens Kamuf
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Bastian Duenges
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Serge C Thal
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Matthias David
- Department of Anesthesiology, Medical Center of the Johannes Gutenberg-University, Langenbeckstrasse 1, 55131, Mainz, Germany.
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Sieck GC, Wylam ME. Paradoxical use of tumor necrosis factor in treating pulmonary edema. Am J Respir Crit Care Med 2014; 190:595-6. [PMID: 25221873 DOI: 10.1164/rccm.201407-1364ed] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Gary C Sieck
- 1 Department of Physiology and Biomedical Engineering Mayo Clinic Rochester, Minnesota
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20
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Czikora I, Alli A, Bao HF, Kaftan D, Sridhar S, Apell HJ, Gorshkov B, White R, Zimmermann A, Wendel A, Pauly-Evers M, Hamacher J, Garcia-Gabay I, Fischer B, Verin A, Bagi Z, Pittet JF, Shabbir W, Lemmens-Gruber R, Chakraborty T, Lazrak A, Matthay MA, Eaton DC, Lucas R. A novel tumor necrosis factor-mediated mechanism of direct epithelial sodium channel activation. Am J Respir Crit Care Med 2014; 190:522-32. [PMID: 25029038 DOI: 10.1164/rccm.201405-0833oc] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
RATIONALE Alveolar liquid clearance is regulated by Na(+) uptake through the apically expressed epithelial sodium channel (ENaC) and basolaterally localized Na(+)-K(+)-ATPase in type II alveolar epithelial cells. Dysfunction of these Na(+) transporters during pulmonary inflammation can contribute to pulmonary edema. OBJECTIVES In this study, we sought to determine the precise mechanism by which the TIP peptide, mimicking the lectin-like domain of tumor necrosis factor (TNF), stimulates Na(+) uptake in a homologous cell system in the presence or absence of the bacterial toxin pneumolysin (PLY). METHODS We used a combined biochemical, electrophysiological, and molecular biological in vitro approach and assessed the physiological relevance of the lectin-like domain of TNF in alveolar liquid clearance in vivo by generating triple-mutant TNF knock-in mice that express a mutant TNF with deficient Na(+) uptake stimulatory activity. MEASUREMENTS AND MAIN RESULTS TIP peptide directly activates ENaC, but not the Na(+)-K(+)-ATPase, upon binding to the carboxy-terminal domain of the α subunit of the channel. In the presence of PLY, a mediator of pneumococcal-induced pulmonary edema, this binding stabilizes the ENaC-PIP2-MARCKS complex, which is necessary for the open probability conformation of the channel and preserves ENaC-α protein expression, by means of blunting the protein kinase C-α pathway. Triple-mutant TNF knock-in mice are more prone than wild-type mice to develop edema with low-dose intratracheal PLY, correlating with reduced pulmonary ENaC-α subunit expression. CONCLUSIONS These results demonstrate a novel TNF-mediated mechanism of direct ENaC activation and indicate a physiological role for the lectin-like domain of TNF in the resolution of alveolar edema during inflammation.
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21
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Hartmann EK, Thomas R, Liu T, Stefaniak J, Ziebart A, Duenges B, Eckle D, Markstaller K, David M. TIP peptide inhalation in experimental acute lung injury: effect of repetitive dosage and different synthetic variants. BMC Anesthesiol 2014; 14:42. [PMID: 24904234 PMCID: PMC4046002 DOI: 10.1186/1471-2253-14-42] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Accepted: 05/21/2014] [Indexed: 12/17/2022] Open
Abstract
Background Inhalation of TIP peptides that mimic the lectin-like domain of TNF-α is a novel approach to attenuate pulmonary oedema on the threshold to clinical application. A placebo-controlled porcine model of acute respiratory distress syndrome (ARDS) demonstrated a reduced thermodilution-derived extravascular lung water index (EVLWI) and improved gas exchange through TIP peptide inhalation within three hours. Based on these findings, the present study compares a single versus a repetitive inhalation of a TIP peptide (TIP-A) and two alternate peptide versions (TIP-A, TIP-B). Methods Following animal care committee approval ARDS was induced by bronchoalveolar lavage followed by injurious ventilation in 21 anaesthetized pigs. A randomised-blinded three-group setting compared the single-dosed peptide variants TIP-A and TIP-B as well as single versus repetitive inhalation of TIP-A (n = 7 per group). Over two three-hour intervals parameters of gas exchange, transpulmonary thermodilution, calculated alveolar fluid clearance, and ventilation/perfusion-distribution were assessed. Post-mortem measurements included pulmonary wet/dry ratio and haemorrhage/congestion scoring. Results The repetitive TIP-A inhalation led to a significantly lower wet/dry ratio than a single dose and a small but significantly lower EVLWI. However, EVLWI changes over time and the derived alveolar fluid clearance did not differ significantly. The comparison of TIP-A and B showed no relevant differences. Gas exchange and ventilation/perfusion-distribution significantly improved in all groups without intergroup differences. No differences were found in haemorrhage/congestion scoring. Conclusions In comparison to a single application the repetitive inhalation of a TIP peptide in three-hour intervals may lead to a small additional reduction the lung water content. Two alternate TIP peptide versions showed interchangeable characteristics.
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Affiliation(s)
- Erik K Hartmann
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
| | - Rainer Thomas
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
| | - Tanghua Liu
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
| | - Joanna Stefaniak
- Department of Anaesthesiology, General Critical Care Medicine and Pain Therapy, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Alexander Ziebart
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
| | - Bastian Duenges
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
| | - Daniel Eckle
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
| | - Klaus Markstaller
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany ; Department of Anaesthesiology, General Critical Care Medicine and Pain Therapy, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Matthias David
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany
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Schwameis R, Eder S, Pietschmann H, Fischer B, Mascher H, Tzotzos S, Fischer H, Lucas R, Zeitlinger M, Hermann R. A FIM study to assess safety and exposure of inhaled single doses of AP301-A specific ENaC channel activator for the treatment of acute lung injury. J Clin Pharmacol 2014; 54:341-50. [PMID: 24515273 PMCID: PMC4160070 DOI: 10.1002/jcph.203] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/01/2013] [Indexed: 11/05/2022]
Abstract
AP301 is an activator of ENaC-mediated Na(+) uptake for the treatment of pulmonary permeability edema in acute respiratory distress syndrome (ARDS). The purpose of this "first-in-man" study was to examine local and systemic safety and systemic exposure of ascending single doses of AP301, when inhaled by healthy male subjects. In a double-blind, placebo-controlled study, 48 healthy male subjects were randomized to 6 ascending dose groups (single doses up to 120 mg) of 8 subjects each (3:1 randomization of AP301: placebo). Serial assessments included spirometry, exhaled nitric oxide (eNO), vital signs, ECG, safety laboratory, adverse events (AE), and blood samples for the quantification of AP301 in plasma. Descriptive statistics was applied. All 48 subjects received treatment, and completed the study as per protocol. No serious, local (e.g., hoarseness, cough, bronchospasm), or dose-limiting AEs were noted. None of the assessments indicated notable dose or time-related alterations of safety outcomes. Observed AP301 systemic exposure levels were very low, with mean Cmax values of <2.5 ng/mL in the highest dose groups. Inhaled AP301 single doses up to 120 mg were safe and well tolerated by healthy male subjects. Distribution of inhaled AP301 was largely confined to the lung, as indicated by very low AP301 systemic exposure levels.
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Affiliation(s)
- Richard Schwameis
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Sandra Eder
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | | | | | | | | | - Rudolf Lucas
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Health Sciences University, Augusta, GA, USA
| | - Markus Zeitlinger
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Robert Hermann
- Clinical Research Appliance, Heinrich-Vingerhut-Weg 3, D-63571, Gelnhausen, Germany
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23
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Hartmann EK, Bentley A, Duenges B, Klein KU, Boehme S, Markstaller K, David M. TIP peptide inhalation in oleic acid-induced experimental lung injury: a post-hoc comparison. BMC Res Notes 2013; 6:385. [PMID: 24070340 PMCID: PMC3849219 DOI: 10.1186/1756-0500-6-385] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 09/25/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The lectin-like domain of TNF-α mimicked by an inhaled TIP peptide represents a novel approach to attenuate a pulmonary edema in respiratory failure, which is on the threshold to clinical application. In extension to a previously published study, which reported an improved pulmonary function following TIP peptide inhalation in a porcine model of lavage-induced lung injury, a post-hoc comparison to additional experiments was conducted. This analysis addresses the hypothesis that oleic acid injection-induced capillary leakage and alveolar necrosis blunts the previously reported beneficial effects of TIP peptide inhalation in a porcine model. FINDINGS Following animal care committee approval lung injury was induced by oleic acid injection in six pigs with a setting strictly according to a previously published protocol that was used for lung-lavaged pigs. Ventilation/perfusion-distribution by multiple inert gas elimination, parameters of gas exchange and pulmonary edema were assessed as surrogates of the pulmonary function. A significantly improved ventilation/perfusion-distribution following TIP inhalation was recognized only in the bronchoalveolar lavage model but not following oleic acid injection. The time course after oleic acid injection yielded no comparable impact of the TIP peptide on gas exchange and edema formation. CONCLUSIONS Reported beneficial effects of the TIP peptide on gas exchange and pulmonary edema were not reproducible in the oleic acid injection model. This analysis assumes that sustained alveolar epithelial necrosis as induced by oleic acid injection may inhibit the TIP-induced edema resolution. Regarding the on-going clinical development of the TIP peptide this approach should hardly be effective in states of severe alveolar epithelial damage.
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Affiliation(s)
- Erik K Hartmann
- Department of Anaesthesiology, Medical Centre of the Johannes Gutenberg-University, Langenbeckstr, 1, 55131 Mainz, Germany.
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Shabbir W, Scherbaum-Hazemi P, Tzotzos S, Fischer B, Fischer H, Pietschmann H, Lucas R, Lemmens-Gruber R. Mechanism of action of novel lung edema therapeutic AP301 by activation of the epithelial sodium channel. Mol Pharmacol 2013; 84:899-910. [PMID: 24077967 DOI: 10.1124/mol.113.089409] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
AP301 [Cyclo(CGQRETPEGAEAKPWYC)], a cyclic peptide comprising the human tumor necrosis factor lectin-like domain (TIP domain) sequence, is currently being developed as a treatment for lung edema and has been shown to reduce extravascular lung water and improve lung function in mouse, rat, and pig models. The current paradigm for liquid homeostasis in the adult mammalian lung is that passive apical uptake of sodium via the amiloride-sensitive epithelial Na⁺ channel (ENaC) and nonselective cyclic-nucleotide-gated cation channels creates the major driving force for reabsorption of water through the alveolar epithelium in addition to other ion channels such as potassium and chloride channels. AP301 can increase amiloride-sensitive current in A549 cells as well as in freshly isolated type II alveolar epithelial cells from different species. ENaC is expressed endogenously in all of these cell types. Consequently, this study was undertaken to determine whether ENaC is the specific target of AP301. The effect of AP301 in A549 cells as well as in human embryonic kidney cells and Chinese hamster ovary cells heterologously expressing human ENaC subunits (α, β, γ, and δ) was measured in patch clamp experiments. The congener TIP peptide AP318 [Cyclo(4-aminobutanoic acid-GQRETPEGAEAKPWYD)] activated ENaC by increasing single-channel open probability. AP301 increased current in proteolytically activated (cleaved) but not near-silent (uncleaved) ENaC in a reversible manner. αβγ- or δβγ-ENaC coexpression was required for maximal activity. No increase in current was observed after deglycosylation of extracellular domains of ENaC. Thus, our data suggest that the specific interaction of AP301 with both endogenously and heterologously expressed ENaC requires precedent binding to glycosylated extracellular loop(s).
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Affiliation(s)
- Waheed Shabbir
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria (W.S., P.S.-H., R.L.-G.); APEPTICO Forschung und Entwicklung GmbH, Vienna, Austria (S.T., B.F., H.F., H.P.); and Division of Pulmonary Medicine, Department of Pharmacology and Toxicology, Vascular Biology Center, Medical College of Georgia, Georgia Regents University, Augusta, Georgia (R.L.)
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