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Madarati H, DeYoung V, Singh K, Sparring T, Kwong AC, Fredenburgh JC, Teney C, Koschinsky ML, Boffa MB, Weitz JI, Kretz CA. Optimization of plasma-based BioID identifies plasminogen as a ligand of ADAMTS13. Sci Rep 2024; 14:9073. [PMID: 38643218 PMCID: PMC11032339 DOI: 10.1038/s41598-024-59672-6] [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: 11/07/2023] [Accepted: 04/13/2024] [Indexed: 04/22/2024] Open
Abstract
ADAMTS13, a disintegrin and metalloprotease with a thrombospondin type 1 motif, member 13, regulates the length of Von Willebrand factor (VWF) multimers and their platelet-binding activity. ADAMTS13 is constitutively secreted as an active protease and is not inhibited by circulating protease inhibitors. Therefore, the mechanisms that regulate ADAMTS13 protease activity are unknown. We performed an unbiased proteomics screen to identify ligands of ADAMTS13 by optimizing the application of BioID to plasma. Plasma BioID identified 5 plasma proteins significantly labeled by the ADAMTS13-birA* fusion, including VWF and plasminogen. Glu-plasminogen, Lys-plasminogen, mini-plasminogen, and apo(a) bound ADAMTS13 with high affinity, whereas micro-plasminogen did not. None of the plasminogen variants or apo(a) bound to a C-terminal truncation variant of ADAMTS13 (MDTCS). The binding of plasminogen to ADAMTS13 was attenuated by tranexamic acid or ε-aminocaproic acid, and tranexamic acid protected ADAMTS13 from plasmin degradation. These data demonstrate that plasminogen is an important ligand of ADAMTS13 in plasma by binding to the C-terminus of ADAMTS13. Plasmin proteolytically degrades ADAMTS13 in a lysine-dependent manner, which may contribute to its regulation. Adapting BioID to identify protein-interaction networks in plasma provides a powerful new tool to study protease regulation in the cardiovascular system.
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Affiliation(s)
- Hasam Madarati
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Veronica DeYoung
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Kanwal Singh
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Taylor Sparring
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Andrew C Kwong
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - James C Fredenburgh
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Cherie Teney
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Marlys L Koschinsky
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Robarts Research Institute, The University of Western Ontario, London, ON, Canada
| | - Michael B Boffa
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Robarts Research Institute, The University of Western Ontario, London, ON, Canada
| | - Jeffrey I Weitz
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada
| | - Colin A Kretz
- Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, ON, Canada.
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2
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McQuilten ZK, Wood EM, Medcalf RL. When to use tranexamic acid for the treatment of major bleeding? J Thromb Haemost 2024; 22:581-593. [PMID: 37827378 DOI: 10.1016/j.jtha.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 08/15/2023] [Accepted: 10/02/2023] [Indexed: 10/14/2023]
Abstract
Tranexamic acid (TXA) is an antifibrinolytic agent originally developed for the management of bleeding in the setting of postpartum hemorrhage (PPH). Over the last 15 years, there has been accumulating evidence on the use of TXA for the treatment of active bleeding in a variety of clinical contexts. Clinical trials have shown that the efficacy and safety of TXA for the treatment of bleeding differ according to the clinical context in which it is being administered, timing of administration, and dose. Early administration is important for efficacy, particularly in trauma and PPH. Further studies are needed to understand the mechanisms by which TXA provides benefit, optimal modes of administration and dosing, and its effect in some clinical settings, such as spontaneous intracerebral hemorrhage. There is no evidence that TXA increases the risk of thrombotic events in patients with major bleeding overall. However, there is evidence of increased risk of venous thrombosis in patients with gastrointestinal bleeding. There is also evidence of increased risk of seizures with the use of higher doses. This review summarizes the current evidence for the use of TXA for patients with active bleeding and highlights the importance of generating evidence of efficacy and safety of hemostatic interventions specific to the bleeding contexts-as findings from 1 clinical setting may not be generalizable to other contexts-and that of individual patient assessment for bleeding, thrombotic, and other risks, as well as important logistical and other practical considerations, to optimize care and outcomes in these settings.
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Affiliation(s)
- Zoe K McQuilten
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia; Department of Haematology, Monash Health, Melbourne, Victoria, Australia.
| | - Erica M Wood
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia; Department of Haematology, Monash Health, Melbourne, Victoria, Australia
| | - Robert L Medcalf
- Central Clinical School, Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia
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3
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Goto S, Goto S. Is there a potential role of inhibition of thrombin-activatable fibrinolysis inhibitor in regulation of local fibrinolytic activities on fibrin thrombi in patients with pulmonary embolism? J Thromb Haemost 2023; 21:2708-2710. [PMID: 37739589 DOI: 10.1016/j.jtha.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 07/02/2023] [Accepted: 07/03/2023] [Indexed: 09/24/2023]
Affiliation(s)
- Shinya Goto
- Department of Medicine (Cardiology), Tokai University School of Medicine, Isehara, Japan.
| | - Shinichi Goto
- Department of Medicine (Cardiology), Tokai University School of Medicine, Isehara, Japan
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4
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Stanford S, Roy A, Cecil T, Hegener O, Schulz P, Turaj A, Lim S, Arbuthnot E. Differences in coagulation-relevant parameters: Comparing cryoprecipitate and a human fibrinogen concentrate. PLoS One 2023; 18:e0290571. [PMID: 37647278 PMCID: PMC10468048 DOI: 10.1371/journal.pone.0290571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 08/09/2023] [Indexed: 09/01/2023] Open
Abstract
BACKGROUND Variable fibrinogen content within cryoprecipitate makes accurate dosing challenging in patients with coagulopathic bleeding, in addition to pathogen transmission risks associated with its administration. Purified and standardized human fibrinogen concentrates (HFCs) represent reliable alternatives. Full cryoprecipitate characterization is required to inform selection of an appropriate fibrinogen source for supplementation therapy. METHODS Extended biochemical comparison of pooled cryoprecipitate and HFC (Fibryga, Octapharma) was performed using commercially available assays to determine levels of variability in cryoprecipitate and HFC. In addition to standard procoagulant factors, measurements included activities of platelet-derived microparticles (PMPs) and plasminogen, and levels of fibrin degradation products. RESULTS Cryoprecipitate contains lower fibrinogen levels than HFC (4.83 vs.19.73 g/L; p<0.001), translating to approximately half the amount of fibrinogen per standard cryoprecipitate dose (two pools, pre-pooled from five donations each) vs. HFC (2.14 vs. 3.95 g; p<0.001). Factor XIII (FXIII) levels were also lower in cryoprecipitate vs. HFC (192.17 vs. 328.33 IU/dL; p = 0.002). Levels of procoagulants in cryoprecipitate, such as von Willebrand Factor (VWF) and factor VIII (FVIII), were highly variable, as was PMP activity. A standard cryoprecipitate dose contains significantly higher levels of measured plasminogen and D-dimer fragments than a standard HFC dose. CONCLUSION The tested HFC is a more reliable fibrinogen and FXIII source for accurate dosing compared with cryoprecipitate. Cryoprecipitate appears considerably less predictable for bleeding management due to wide variation in pro- and anticoagulation factors, the presence of PMPs, and the potential to elevate VWF and FVIII to prothrombotic levels.
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Affiliation(s)
- Sophia Stanford
- Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Basingstoke, United Kingdom
| | - Ashok Roy
- Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Basingstoke, United Kingdom
| | - Tom Cecil
- Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Basingstoke, United Kingdom
| | | | - Petra Schulz
- Octapharma Pharmazeutika Produktionsges.m.b.H., Vienna, Austria
| | - Anna Turaj
- Faculty of Medicine, Centre for Cancer Immunology, University of Southampton, University Hospital Southampton, Southampton, United Kingdom
| | - Sean Lim
- Faculty of Medicine, Centre for Cancer Immunology, University of Southampton, University Hospital Southampton, Southampton, United Kingdom
| | - Emily Arbuthnot
- Peritoneal Malignancy Institute, Basingstoke and North Hampshire Hospital, Basingstoke, United Kingdom
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5
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Risman RA, Kirby NC, Bannish BE, Hudson NE, Tutwiler V. Fibrinolysis: an illustrated review. Res Pract Thromb Haemost 2023; 7:100081. [PMID: 36942151 PMCID: PMC10024051 DOI: 10.1016/j.rpth.2023.100081] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 01/16/2023] [Accepted: 01/25/2023] [Indexed: 02/18/2023] Open
Abstract
In response to vessel injury (or other pathological conditions), the hemostatic process is activated, resulting in a fibrous, cellular-rich structure commonly referred to as a blood clot. Succeeding the clot's function in wound healing, it must be resolved. This illustrated review focuses on fibrinolysis-the degradation of blood clots or thrombi. Fibrin is the main mechanical and structural component of a blood clot, which encases the cellular components of the clot, including platelets and red blood cells. Fibrinolysis is the proteolytic degradation of the fibrin network that results in the release of the cellular components into the bloodstream. In the case of thrombosis, fibrinolysis is required for restoration of blood flow, which is accomplished clinically through exogenously delivered lytic factors in a process called external lysis. Fibrinolysis is regulated by plasminogen activators (tissue-type and urokinase-type) that convert plasminogen into plasmin to initiate fiber lysis and lytic inhibitors that impede this lysis (plasminogen activator inhibitors, alpha 2-antiplasmin, and thrombin activatable fibrinolysis inhibitor). Furthermore, the network structure has been shown to regulate lysis: thinner fibers and coarser clots lyse faster than thicker fibers and finer clots. Clot contraction, a result of platelets pulling on fibers, results in densely packed red blood cells (polyhedrocytes), reduced permeability to fibrinolytic factors, and increased fiber tension. Extensive research in the field has allowed for critical advancements leading to improved thrombolytic agents. In this review, we summarize the state of the field, highlight gaps in knowledge, and propose future research questions.
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Affiliation(s)
| | - Nicholas C Kirby
- Department of Chemistry, East Carolina University, Greenville, North Carolina, USA
| | | | - Nathan E Hudson
- Department of Physics, East Carolina University Greenville, North Carolina, USA
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6
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Yatsenko T, Skrypnyk M, Troyanovska O, Tobita M, Osada T, Takahashi S, Hattori K, Heissig B. The Role of the Plasminogen/Plasmin System in Inflammation of the Oral Cavity. Cells 2023; 12:cells12030445. [PMID: 36766787 PMCID: PMC9913802 DOI: 10.3390/cells12030445] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/26/2023] [Accepted: 01/28/2023] [Indexed: 02/03/2023] Open
Abstract
The oral cavity is a unique environment that consists of teeth surrounded by periodontal tissues, oral mucosae with minor salivary glands, and terminal parts of major salivary glands that open into the oral cavity. The cavity is constantly exposed to viral and microbial pathogens. Recent studies indicate that components of the plasminogen (Plg)/plasmin (Pm) system are expressed in tissues of the oral cavity, such as the salivary gland, and contribute to microbial infection and inflammation, such as periodontitis. The Plg/Pm system fulfills two major functions: (a) the destruction of fibrin deposits in the bloodstream or damaged tissues, a process called fibrinolysis, and (b) non-fibrinolytic actions that include the proteolytic modulation of proteins. One can observe both functions during inflammation. The virus that causes the coronavirus disease 2019 (COVID-19) exploits the fibrinolytic and non-fibrinolytic functions of the Plg/Pm system in the oral cavity. During COVID-19, well-established coagulopathy with the development of microthrombi requires constant activation of the fibrinolytic function. Furthermore, viral entry is modulated by receptors such as TMPRSS2, which is necessary in the oral cavity, leading to a derailed immune response that peaks in cytokine storm syndrome. This paper outlines the significance of the Plg/Pm system for infectious and inflammatory diseases that start in the oral cavity.
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Affiliation(s)
- Tetiana Yatsenko
- Department of Research Support Utilizing Bioresource Bank, Graduate School of Medicine, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421, Japan
| | - Maksym Skrypnyk
- Department of Research Support Utilizing Bioresource Bank, Graduate School of Medicine, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421, Japan
| | - Olga Troyanovska
- Department of Research Support Utilizing Bioresource Bank, Graduate School of Medicine, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421, Japan
| | - Morikuni Tobita
- Department of Oral and Maxillofacial Surgery, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421, Japan
| | - Taro Osada
- Department of Gastroenterology, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu-Shi 279-0021, Japan
| | - Satoshi Takahashi
- Division of Clinical Genome Research, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-Ku, Tokyo 108-8639, Japan
| | - Koichi Hattori
- Center for Genome and Regenerative Medicine, Graduate School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421, Japan
- Correspondence: (K.H.); (B.H.); Tel.: +81-3-3813-3111 (switchboard 2115) (B.H.)
| | - Beate Heissig
- Department of Research Support Utilizing Bioresource Bank, Graduate School of Medicine, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421, Japan
- Correspondence: (K.H.); (B.H.); Tel.: +81-3-3813-3111 (switchboard 2115) (B.H.)
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7
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Bunch CM, Chang E, Moore EE, Moore HB, Kwaan HC, Miller JB, Al-Fadhl MD, Thomas AV, Zackariya N, Patel SS, Zackariya S, Haidar S, Patel B, McCurdy MT, Thomas SG, Zimmer D, Fulkerson D, Kim PY, Walsh MR, Hake D, Kedar A, Aboukhaled M, Walsh MM. SHock-INduced Endotheliopathy (SHINE): A mechanistic justification for viscoelastography-guided resuscitation of traumatic and non-traumatic shock. Front Physiol 2023; 14:1094845. [PMID: 36923287 PMCID: PMC10009294 DOI: 10.3389/fphys.2023.1094845] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 02/07/2023] [Indexed: 03/03/2023] Open
Abstract
Irrespective of the reason for hypoperfusion, hypocoagulable and/or hyperfibrinolytic hemostatic aberrancies afflict up to one-quarter of critically ill patients in shock. Intensivists and traumatologists have embraced the concept of SHock-INduced Endotheliopathy (SHINE) as a foundational derangement in progressive shock wherein sympatho-adrenal activation may cause systemic endothelial injury. The pro-thrombotic endothelium lends to micro-thrombosis, enacting a cycle of worsening perfusion and increasing catecholamines, endothelial injury, de-endothelialization, and multiple organ failure. The hypocoagulable/hyperfibrinolytic hemostatic phenotype is thought to be driven by endothelial release of anti-thrombogenic mediators to the bloodstream and perivascular sympathetic nerve release of tissue plasminogen activator directly into the microvasculature. In the shock state, this hemostatic phenotype may be a counterbalancing, yet maladaptive, attempt to restore blood flow against a systemically pro-thrombotic endothelium and increased blood viscosity. We therefore review endothelial physiology with emphasis on glycocalyx function, unique biomarkers, and coagulofibrinolytic mediators, setting the stage for understanding the pathophysiology and hemostatic phenotypes of SHINE in various etiologies of shock. We propose that the hyperfibrinolytic phenotype is exemplified in progressive shock whether related to trauma-induced coagulopathy, sepsis-induced coagulopathy, or post-cardiac arrest syndrome-associated coagulopathy. Regardless of the initial insult, SHINE appears to be a catecholamine-driven entity which early in the disease course may manifest as hyper- or hypocoagulopathic and hyper- or hypofibrinolytic hemostatic imbalance. Moreover, these hemostatic derangements may rapidly evolve along the thrombohemorrhagic spectrum depending on the etiology, timing, and methods of resuscitation. Given the intricate hemochemical makeup and changes during these shock states, macroscopic whole blood tests of coagulative kinetics and clot strength serve as clinically useful and simple means for hemostasis phenotyping. We suggest that viscoelastic hemostatic assays such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM) are currently the most applicable clinical tools for assaying global hemostatic function-including fibrinolysis-to enable dynamic resuscitation with blood products and hemostatic adjuncts for those patients with thrombotic and/or hemorrhagic complications in shock states.
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Affiliation(s)
- Connor M Bunch
- Department of Emergency Medicine, Henry Ford Hospital, Detroit, MI, United States.,Department of Internal Medicine, Henry Ford Hospital, Detroit, MI, United States
| | - Eric Chang
- Department of Medical Education, Indiana University School of Medicine, Notre Dame Campus, South Bend, IN, United States
| | - Ernest E Moore
- Department of Surgery, Ernest E. Moore Shock Trauma Center at Denver Health, University of Colorado, Denver, CO, United States
| | - Hunter B Moore
- Department of Surgery, Ernest E. Moore Shock Trauma Center at Denver Health, University of Colorado, Denver, CO, United States.,Department of Transplant Surgery, Denver Health and University of Colorado Health Sciences Center, Denver, CO, United States
| | - Hau C Kwaan
- Division of Hematology and Oncology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Joseph B Miller
- Department of Emergency Medicine, Henry Ford Hospital, Detroit, MI, United States.,Department of Internal Medicine, Henry Ford Hospital, Detroit, MI, United States
| | - Mahmoud D Al-Fadhl
- Department of Medical Education, Indiana University School of Medicine, Notre Dame Campus, South Bend, IN, United States
| | - Anthony V Thomas
- Department of Medical Education, Indiana University School of Medicine, Notre Dame Campus, South Bend, IN, United States
| | - Nuha Zackariya
- Department of Medical Education, Indiana University School of Medicine, Notre Dame Campus, South Bend, IN, United States
| | - Shivani S Patel
- Department of Emergency Medicine, Henry Ford Hospital, Detroit, MI, United States
| | - Sufyan Zackariya
- Department of Emergency Medicine, Henry Ford Hospital, Detroit, MI, United States
| | - Saadeddine Haidar
- Department of Emergency Medicine, Henry Ford Hospital, Detroit, MI, United States
| | - Bhavesh Patel
- Division of Critical Care, Department of Medicine, Mayo Clinic Arizona, Phoenix, AZ, United States
| | - Michael T McCurdy
- Division of Pulmonary and Critical Care, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Scott G Thomas
- Department of Trauma Surgery, Memorial Leighton Trauma Center, South Bend, IN, United States
| | - Donald Zimmer
- Department of Trauma Surgery, Memorial Leighton Trauma Center, South Bend, IN, United States
| | - Daniel Fulkerson
- Department of Trauma Surgery, Memorial Leighton Trauma Center, South Bend, IN, United States
| | - Paul Y Kim
- Department of Medicine, McMaster University, Hamilton, ON, Canada.,Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada
| | | | - Daniel Hake
- Departments of Emergency Medicine and Internal Medicine, Saint Joseph Regional Medical Center, Mishawaka, IN, United States
| | - Archana Kedar
- Departments of Emergency Medicine and Internal Medicine, Saint Joseph Regional Medical Center, Mishawaka, IN, United States
| | - Michael Aboukhaled
- Departments of Emergency Medicine and Internal Medicine, Saint Joseph Regional Medical Center, Mishawaka, IN, United States
| | - Mark M Walsh
- Department of Medical Education, Indiana University School of Medicine, Notre Dame Campus, South Bend, IN, United States.,Departments of Emergency Medicine and Internal Medicine, Saint Joseph Regional Medical Center, Mishawaka, IN, United States
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8
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Bouthors AS, Gilliot S, Sentilhes L, Hennart B, Jeanpierre E, Deneux-Tharaux C, Lebuffe G, Odou P. The role of tranexamic acid in the management of postpartum haemorrhage. Best Pract Res Clin Anaesthesiol 2022; 36:411-426. [PMID: 36513435 DOI: 10.1016/j.bpa.2022.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 12/15/2022]
Abstract
In the last decades, tranexamic acid (TXA) has emerged as an essential tool in blood loss management in obstetrics. TXA prophylaxis for postpartum haemorrhage (PPH) has been studied in double-blind, placebo-controlled, randomized clinical trials (RCTs). Given the small observed preventive effect, the systematic use of TXA for vaginal and/or caesarean deliveries remains controversial. The result of a pharmacokinetic modelling suggests that relative to intravenous administration, intramuscular administration may be an equally effective alternative route for preventing PPH and may enable access to this drug in low-resource countries. Prophylaxis is currently studied in high-risk populations, such as women with prepartum anaemia or placenta previa. TXA effectively reduces blood loss and PPH-related morbidity and mortality during active PPH, as demonstrated by high-grade evidence from large RCTs. The drug has a good safety profile: in most cases, only mild gastrointestinal or visual adverse events may be observed. TXA use does not increase the risk of serious adverse events, such as venous or arterial thromboembolism, seizures, or acute kidney injury. The TRACES in vivo analysis of biomarkers of TXA's antifibrinolytic effect have suggested that a dose of at least 1 g is required for the treatment of PPH. The TRACES pharmacokinetic model suggests that because TXA can be lost in the haemorrhaged blood, a second dose should be administered if the PPH continues or if severe coagulopathy occurs. Future pharmacodynamic analyses will focus on the appropriateness of TXA dosing regimens with regard to the intensity of fibrinolysis in catastrophic obstetric events.
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Affiliation(s)
- Anne-Sophie Bouthors
- Anaesthesia Intensive Care Unit, Jeanne de Flandre Women's Hospital, Lille University Medical Centre, F-59037, Lille, France; Univ. Lille, ULR 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associées, F-59000, Lille, France.
| | - Sixtine Gilliot
- Univ. Lille, ULR 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associées, F-59000, Lille, France; Central Pharmacy, Lille University Medical Centre, F-59037, Lille, France.
| | - Loïc Sentilhes
- Department of Obstetrics and Gynaecology, Bordeaux University Hospital, F-33076 Bordeaux, France
| | - Benjamin Hennart
- Toxicology Unit, Biology and Pathology Centre, Lille University Medical Centre, F-59037, Lille, France
| | - Emmanuelle Jeanpierre
- Haemostasis Unit, Biology and Pathology Centre, Lille University Medical Centre, F-59037, Lille, France
| | - Catherine Deneux-Tharaux
- Université Paris Cité, CRESS UMR 1153, Obstetrical Perinatal and Paediatric Epidemiology Research Team, EPOPé, INSERM, F75014 Paris, France
| | - Gilles Lebuffe
- Univ. Lille, ULR 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associées, F-59000, Lille, France; Anaesthesia and Intensive Care Unit, Lille University Medical Centre, F-59037 Lille, France
| | - Pascal Odou
- Univ. Lille, ULR 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associées, F-59000, Lille, France; Central Pharmacy, Lille University Medical Centre, F-59037, Lille, France
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9
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Gando S, Shiraishi A, Wada T, Yamakawa K, Fujishima S, Saitoh D, Kushimoto S, Ogura H, Abe T, Mayumi T, Sasaki J, Kotani J, Takeyama N, Tsuruta R, Takuma K, Shiraishi SI, Shiino Y, Nakada TA, Okamoto K, Sakamoto Y, Hagiwara A, Fujimi S, Umemura Y, Otomo Y. Effects of tranexamic acid on coagulofibrinolytic markers during the early stage of severe trauma: A propensity score-matched analysis. Medicine (Baltimore) 2022; 101:e29711. [PMID: 35960088 PMCID: PMC9371565 DOI: 10.1097/md.0000000000029711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Tranexamic acid (TXA) reduces the risk of bleeding trauma death without altering the need for blood transfusion. We examined the effects of TXA on coagulation and fibrinolysis dynamics and the volume of transfusion during the early stage of trauma. This subanalysis of a prospective multicenter study of severe trauma included 276 patients divided into propensity score-matched groups with and without TXA administration. The effects of TXA on coagulation and fibrinolysis markers immediately at (time point 0) and 3 hours after (time point 3) arrival at the emergency department were investigated. The transfusion volume was determined at 24 hours after admission. TXA was administered to the patients within 3 hours (median, 64 minutes) after injury. Significant reductions in fibrin/fibrinogen degradation products and D-dimer levels from time points 0 to 3 in the TXA group compared with the non-TXA group were confirmed, with no marked differences noted in the 24-hour transfusion volumes between the 2 groups. Continuously increased levels of soluble fibrin, a marker of thrombin generation, from time points 0 to 3 and high levels of plasminogen activator inhibitor-1, a marker of inhibition of fibrinolysis, at time point 3 were observed in both groups. TXA inhibited fibrin(ogen)olysis during the early stage of severe trauma, although this was not associated with a reduction in the transfusion volume. Other confounders affecting the dynamics of fibrinolysis and transfusion requirement need to be clarified.
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Affiliation(s)
- Satoshi Gando
- Division of Acute and Critical Care Medicine, Department of Anesthesiology and Critical Care Medicine, Hokkaido University Faculty of Medicine, Japan
- Department of Acute and Critical Care Medicine, Sapporo Higashi Tokushukai Hospital, Japan
- *Correspondence: Satoshi Gando, Department of Acute and Critical Care Medicine, Sapporo Higashi Tokushukai Hospital, N33E14, Higashi-ku 065-0033, Japan (e-mail: )
| | | | - Takeshi Wada
- Division of Acute and Critical Care Medicine, Department of Anesthesiology and Critical Care Medicine, Hokkaido University Faculty of Medicine, Japan
| | - Kazuma Yamakawa
- Department of Emergency Medicine, Osaka Medical College, Japan
| | - Seitaro Fujishima
- Center for General Medicine Education, Keio University School of Medicine, Japan
| | - Daizoh Saitoh
- Division of Traumatology, Research Institute, National Defense Medical College, Japan
| | - Shigeki Kushimoto
- Division of Emergency and Critical Care Medicine, Tohoku University Graduate School of Medicine, Japan
| | - Hiroshi Ogura
- Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Japan
| | - Toshikazu Abe
- Department of Emergency and Critical Care Medicine, Tsukuba Memorial Hospital, Tsukuba, Japan
- Health Services Research and Development Center, University of Tsukuba, Japan
| | - Toshihiko Mayumi
- Department of Emergency Medicine, School of Medicine, University of Occupational and Environmental Health, Japan
| | - Junichi Sasaki
- Department of Emergency and Critical Care Medicine, Keio University School of Medicine, Japan
| | - Joji Kotani
- Division of Disaster and Emergency Medicine, Department of Surgery Related, Kobe University Graduate School of Medicine, Japan
| | - Naoshi Takeyama
- Advanced Critical Care Center, Aichi Medical University Hospital, Japan
| | - Ryosuke Tsuruta
- Advanced Medical Emergency and Critical Care Center, Yamaguchi University Hospital, Japan
| | - Kiyotsugu Takuma
- Emergency and Critical Care Center, Kawasaki Municipal Hospital, Japan
| | | | - Yasukazu Shiino
- Department of Acute Medicine, Kawasaki Medical School, Japan
| | - Taka-aki Nakada
- Department of Emergency and Critical Care Medicine, Chiba University Graduate School of Medicine, Japan
| | - Kohji Okamoto
- Department of Surgery, Center for Gastroenterology and Liver Disease, Kitakyushu City Yahata Hospital, Japan
| | - Yuichiro Sakamoto
- Emergency and Critical Care Medicine, Saga University Hospital, Japan
| | - Akiyoshi Hagiwara
- Center Hospital of the National Center for Global Health and Medicine, Japan
| | - Satoshi Fujimi
- Division of Trauma and Surgical Critical Care, Osaka General Medical Center, Japan
| | - Yutaka Umemura
- Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Japan
| | - Yasuhiro Otomo
- Trauma and Acute Critical Care Center, Medical Hospital, Tokyo Medical and Dental University, Japan
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10
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Valke LLFG, Meijer D, Nieuwenhuizen L, Laros‐van Gorkom BAP, Blijlevens NMA, Heerde WL, Schols SEM. Fibrinolytic assays in bleeding of unknown cause: Improvement in diagnostic yield. Res Pract Thromb Haemost 2022; 6:e12681. [PMID: 35316940 PMCID: PMC8922970 DOI: 10.1002/rth2.12681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/28/2022] [Accepted: 01/31/2022] [Indexed: 11/11/2022] Open
Abstract
Introduction Aim Methods Results Discussion
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Affiliation(s)
- Lars L. F. G. Valke
- Department of Hematology Radboud University Medical Center Nijmegen The Netherlands
- Hemophilia Treatment Center Nijmegen‐Eindhoven‐Maastricht The Netherlands
| | - Danielle Meijer
- Department of Laboratory Medicine Laboratory of Hematology Radboud University Medical Center Nijmegen The Netherlands
| | - Laurens Nieuwenhuizen
- Hemophilia Treatment Center Nijmegen‐Eindhoven‐Maastricht The Netherlands
- Department of Hematology Maxima Medical Center Veldhoven The Netherlands
| | - Britta A. P. Laros‐van Gorkom
- Department of Hematology Radboud University Medical Center Nijmegen The Netherlands
- Hemophilia Treatment Center Nijmegen‐Eindhoven‐Maastricht The Netherlands
| | | | - Waander L. Heerde
- Hemophilia Treatment Center Nijmegen‐Eindhoven‐Maastricht The Netherlands
- Enzyre BV Novio Tech Campus Nijmegen The Netherlands
| | - Saskia E. M. Schols
- Department of Hematology Radboud University Medical Center Nijmegen The Netherlands
- Hemophilia Treatment Center Nijmegen‐Eindhoven‐Maastricht The Netherlands
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11
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Fibrin(ogen) as a Therapeutic Target: Opportunities and Challenges. Int J Mol Sci 2021; 22:ijms22136916. [PMID: 34203139 PMCID: PMC8268464 DOI: 10.3390/ijms22136916] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 12/19/2022] Open
Abstract
Fibrinogen is one of the key molecular players in haemostasis. Thrombin-mediated release of fibrinopeptides from fibrinogen converts this soluble protein into a network of fibrin fibres that form a building block for blood clots. Thrombin-activated factor XIII further crosslinks the fibrin fibres and incorporates antifibrinolytic proteins into the network, thus stabilising the clot. The conversion of fibrinogen to fibrin also exposes binding sites for fibrinolytic proteins to limit clot formation and avoid unwanted extension of the fibrin fibres. Altered clot structure and/or incorporation of antifibrinolytic proteins into fibrin networks disturbs the delicate equilibrium between clot formation and lysis, resulting in either unstable clots (predisposing to bleeding events) or persistent clots that are resistant to lysis (increasing risk of thrombosis). In this review, we discuss the factors responsible for alterations in fibrin(ogen) that can modulate clot stability, in turn predisposing to abnormal haemostasis. We also explore the mechanistic pathways that may allow the use of fibrinogen as a potential therapeutic target to treat vascular thrombosis or bleeding disorders. Better understanding of fibrinogen function will help to devise future effective and safe therapies to modulate thrombosis and bleeding risk, while maintaining the fine balance between clot formation and lysis.
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12
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Tranexamic acid rapidly inhibits fibrinolysis, yet transiently enhances plasmin generation in vivo. Blood Coagul Fibrinolysis 2021; 32:172-179. [PMID: 33443933 DOI: 10.1097/mbc.0000000000001008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tranexamic acid (TXA) is a lysine analogue that inhibits plasmin generation and has been used for decades as an antifibrinolytic agent to reduce bleeding. Recent reports have indicated that TXA can paradoxically promote plasmin generation. Blood was obtained from 41 cardiac surgical patients randomly assigned to TXA or placebo before start of surgery (preOP), at the end of surgery (EOS), then again on postoperative day 1 (POD-1) as well as POD-3. Plasma levels of tissue-type plasminogen activator (t-PA), urokinase (u-PA), the plasmin-antiplasmin (PAP) complex, as well as t-PA and u-PA-induced clot lysis assays were then determined. Clot lysis and PAP complex levels were also assessed in healthy volunteers before and at various time points after taking 1 g TXA orally. Surgery induced an increase in circulating t-PA, yet not u-PA at EOS. t-PA levels were unaffected by TXA; however, u-PA levels were significantly reduced in patients on POD-3. t-PA and u-PA-induced clot lysis were both inhibited in plasma from TXA-treated patients. In contrast, PAP complex formation, representing plasmin generation, was unexpectedly enhanced in the plasma of patients administered TXA at the EOS time point. In healthy volunteers, oral TXA effectively blocked fibrinolysis within 30 min and blockade was sustained for 8 h. However, TXA also increased PAP levels in volunteers 4 h after administration. Our findings demonstrate that TXA can actually augment PAP complex formation, consistent with an increase in plasmin generation in vivo despite the fact that it blocks fibrinolysis within 30 min. This may have unanticipated consequences in vivo.
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13
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Tranexamic acid is associated with reduced complement activation in trauma patients with hemorrhagic shock and hyperfibrinolysis on thromboelastography. Blood Coagul Fibrinolysis 2021; 31:578-582. [PMID: 32732500 DOI: 10.1097/mbc.0000000000000938] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
: Trauma with hemorrhagic shock causes massive tissue plasminogen activator release, plasmin generation, and hyperfibrinolysis. Tranexamic acid (TXA) has recently been used to treat bleeding in trauma by preventing plasmin generation to limit fibrinolysis. Trauma patients also have increased complement activation that correlates with mortality and organ failure, but the source of activation is not clear, and plasmin has recently been shown to efficiently cleave C3 and C5 to their activated fragments. We hypothesized that trauma patients in hemorrhagic shock with hyperfibrinolysis on thromboelastography (TEG) LY30 would have increased complement activation at early time points, as measured by soluble C5b-9 complex, and TXA would prevent this. Plasma samples were obtained from an unrelated, previously performed IRB-approved prospective randomized study of trauma patients. Three groups were studied with n = 5 patients in each group: patients without hyperfibrinolysis (TEG LY30 < 3%) (who therefore did not get TXA), patients with hyperfibrinolysis (TEG LY30 > 3%) who did not get TXA, and patients with hyperfibrinolysis who were then treated with TXA. We found that patients who did not receive TXA, regardless of fibrinolytic phenotype, had elevated soluble C5b-9 levels at 6 h relative to emergency department levels. In contrast, all five patients with initial TEG LY30 more than 3% and were then treated with TXA had reduced soluble C5b-9 levels at 6 h relative to emergency department levels. There were no differences in PF1 + 2, Bb, or C4d levels between groups, suggesting that coagulation and complement activation pathways may not be primarily responsible for the observed differences.
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14
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Sillen M, Declerck PJ. Thrombin Activatable Fibrinolysis Inhibitor (TAFI): An Updated Narrative Review. Int J Mol Sci 2021; 22:ijms22073670. [PMID: 33916027 PMCID: PMC8036986 DOI: 10.3390/ijms22073670] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/26/2021] [Accepted: 03/29/2021] [Indexed: 01/02/2023] Open
Abstract
Thrombin activatable fibrinolysis inhibitor (TAFI), a proenzyme, is converted to a potent attenuator of the fibrinolytic system upon activation by thrombin, plasmin, or the thrombin/thrombomodulin complex. Since TAFI forms a molecular link between coagulation and fibrinolysis and plays a potential role in venous and arterial thrombotic diseases, much interest has been tied to the development of molecules that antagonize its function. This review aims at providing a general overview on the biochemical properties of TAFI, its (patho)physiologic function, and various strategies to stimulate the fibrinolytic system by interfering with (activated) TAFI functionality.
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15
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Assessing Plasmin Generation in Health and Disease. Int J Mol Sci 2021; 22:ijms22052758. [PMID: 33803235 PMCID: PMC7963172 DOI: 10.3390/ijms22052758] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/20/2021] [Accepted: 03/05/2021] [Indexed: 12/13/2022] Open
Abstract
Fibrinolysis is an important process in hemostasis responsible for dissolving the clot during wound healing. Plasmin is a central enzyme in this process via its capacity to cleave fibrin. The kinetics of plasmin generation (PG) and inhibition during fibrinolysis have been poorly understood until the recent development of assays to quantify these metrics. The assessment of plasmin kinetics allows for the identification of fibrinolytic dysfunction and better understanding of the relationships between abnormal fibrin dissolution and disease pathogenesis. Additionally, direct measurement of the inhibition of PG by antifibrinolytic medications, such as tranexamic acid, can be a useful tool to assess the risks and effectiveness of antifibrinolytic therapy in hemorrhagic diseases. This review provides an overview of available PG assays to directly measure the kinetics of plasmin formation and inhibition in human and mouse plasmas and focuses on their applications in defining the role of plasmin in diseases, including angioedema, hemophilia, rare bleeding disorders, COVID-19, or diet-induced obesity. Moreover, this review introduces the PG assay as a promising clinical and research method to monitor antifibrinolytic medications and screen for genetic or acquired fibrinolytic disorders.
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16
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Abstract
Physiological fibrinolysis under normal conditions progresses slowly, in contrast to coagulation which is triggered rapidly to stop bleeding and defend against microbial invasion. Methods to detect fibrinolysis abnormalities are less simple and poorly standardized compared with common coagulation tests. Fibrinolysis can be accelerated by preparing euglobulin from plasma to reduce endogenous inhibitors, or by adding plasminogen activators to normal plasma. However, these manipulations complicate interpretation of results and diagnosis of a "fibrinolysis deficit." Many observational studies on antigen levels of fibrinolysis inhibitors, plasminogen activator inhibitor 1 or thrombin-activatable fibrinolysis inhibitor, zymogen or active enzyme have been published. However, conclusions are mixed and there are clear problems with harmonization of results. Viscoelastic methods have the advantage of being rapid and are used as point-of-care tests. They also work with whole blood, allowing the contribution of platelets to be explored. However, there are no agreed protocols for applying viscoelastic methods in acute care for the diagnosis of hyperfibrinolysis or to direct therapy. The emergence of SARS-CoV-2 and the dangers of associated coagulopathy provide new challenges. A common finding in hospitalized patients is high levels of D-dimer fibrin breakdown products, indicative of ongoing fibrinolysis. Well-established problems with D-dimer testing standardization signal that we should be cautious in using results from such tests as prognostic indicators or to target therapies.
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Affiliation(s)
- Colin Longstaff
- Department of Biotherapeutics, National Institute for Biological Standards and Control, South Mimms, Herts, United Kingdom
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17
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Whyte CS, Mutch NJ. uPA-mediated plasminogen activation is enhanced by polyphosphate. Haematologica 2021; 106:522-531. [PMID: 32029503 PMCID: PMC7849561 DOI: 10.3324/haematol.2019.237966] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 01/31/2020] [Indexed: 11/09/2022] Open
Abstract
Tissue plasminogen activator (tPA) and urokinase (uPA) differ in their modes of action. Efficient tPA-mediated plasminogen activation requires binding to fibrin. In contrast, uPA is fibrin independent and activates plasminogen in solution or when associated with its cellular receptor uPAR. We have previously shown that polyphosphate (polyP), alters fibrin structure and attenuates tPA and plasminogen binding to fibrin, thereby down-regulating fibrinolysis. Here we investigate the impact of polyP on uPA-mediated fibrinolysis. As previously reported polyP of an average chain length of 65 (polyP65) delays tPA-mediated fibrinolysis. The rate of plasmin generation was also delayed and reduced 1.6-fold in polyP65-containing clots (0.74 ± 0.06 vs. 1.17 ± 0.14 pM/s in P < 0.05). Analysis of tPA-mediated fibrinolysis in real-time by confocal microscopy was significantly slower in polyP65-containing clots. In marked contrast, polyP65 augmented the rate of uPA-mediated plasmin generation 4.7-fold (3.96 ± 0.34 vs. 0.84 ± 0.08 pM/s; P < 0.001) and accelerated fibrinolysis (t1/2 64.5 ± 1.7 min vs. 108.2 ± 3.8 min; P < 0.001). Analysis of lysis in real-time confirmed that polyP65 enhanced uPA-mediated fibrinolysis. Varying the plasminogen concentration (0.125 to 1 μM) in clots dose-dependently enhanced uPA-mediated fibrinolysis, while negligible changes were observed on tPA-mediated fibrinolysis. The accelerating effect of polyP65 on uPA-mediated fibrinolysis was overcome by additional plasminogen, while the down-regulation of tPA-mediated lysis and plasmin generation was largely unaffected. PolyP65 exerts opposing effects on tPA- and uPA-mediated fibrinolysis, attenuating the fibrin cofactor function in tPA-mediated plasminogen activation. In contrast, polyP may facilitate the interaction between fibrin-independent uPA and plasminogen thereby accelerating plasmin generation and downstream fibrinolysis.
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18
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Miszta A, Ahmadzia HK, Luban NLC, Li S, Guo D, Holle LA, Berger JS, James AH, Gobburu JVS, van den Anker J, de Laat B, Wolberg AS. Application of a plasmin generation assay to define pharmacodynamic effects of tranexamic acid in women undergoing cesarean delivery. J Thromb Haemost 2021; 19:221-232. [PMID: 33001565 PMCID: PMC7875467 DOI: 10.1111/jth.15114] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/27/2022]
Abstract
Essentials Tranexamic acid (TXA) is an antifibrinolytic drug used to reduce bleeding. Assaying plasmin generation (PG) in plasma detects clinically relevant TXA levels in vitro and ex vivo. 3.1-16.2 µg/mL TXA half-maximally inhibits PG in plasma from women undergoing cesarean delivery. PG velocity shows the strongest dose-relationship at low TXA concentrations (≤10 µg/mL). ABSTRACT: Background Tranexamic acid (TXA) is used to reduce bleeding. TXA inhibits plasmin(ogen) binding to fibrin and reduces fibrinolysis. TXA antifibrinolytic activity is typically measured by clot lysis assays; however, effects on plasmin generation (PG) are unclear due to a lack of tools to measure PG in plasma. Aims Develop an assay to measure PG kinetics in human plasma. Determine effects of TXA on PG and compare with fibrinolysis measured by rotational thromboelastometry (ROTEM). Methods We characterized effects of plasminogen, tissue plasminogen activator, fibrinogen, and α2 -antiplasmin on PG in vitro. We also studied effects of TXA on PG in plasma from 30 pregnant women administered intravenous TXA (5, 10, or 15 mg/kg) during cesarean delivery. PG was measured by calibrated fluorescence. PG parameters were compared with TXA measured by mass spectrometry and ROTEM of whole blood. Results The PG assay is specific for plasmin and sensitive to tissue plasminogen activator, fibrin(ogen), and α2 -antiplasmin. Addition of TXA to plasma in vitro dose dependently prolonged the clot lysis time and delayed and reduced PG. For all doses of TXA administered intravenously, the PG assay detected delayed time-to-peak (≤3 hours) and reduced the velocity, peak, and endogenous plasmin potential (≤24 hours) in plasma samples obtained after infusion. The PG time-to-peak, velocity, and peak correlated significantly with TXA concentration and showed less variability than the ROTEM lysis index at 30 minutes or maximum lysis. Conclusions The PG assay detects pharmacologically relevant concentrations of TXA administered in vitro and in vivo, and demonstrates TXA-mediated inhibition of PG in women undergoing cesarean delivery.
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Affiliation(s)
- Adam Miszta
- Department of Pathology and UNC Blood Research Center, University of North Carolina, Chapel Hill, NC, USA
- Synapse Research Institute, Maastricht, The Netherlands
| | - Homa K. Ahmadzia
- Division of Maternal-Fetal Medicine, Department of Obstetrics & Gynecology, The George Washington University, Washington, DC, USA
| | - Naomi L. C. Luban
- Division of Hematology/Oncology, Department of Pediatrics and Pathology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Shuhui Li
- Center for Translational Medicine, School of Pharmacy, University of Maryland, Baltimore, MD, USA
| | - Dong Guo
- Center for Translational Medicine, School of Pharmacy, University of Maryland, Baltimore, MD, USA
| | - Lori A. Holle
- Department of Pathology and UNC Blood Research Center, University of North Carolina, Chapel Hill, NC, USA
| | - Jeffrey S. Berger
- Department of Anesthesiology, The George Washington University, Washington, DC, USA
| | - Andra H. James
- Division of Maternal-Fetal Medicine, Department of Obstetrics & Gynecology, Duke University, Durham, NC, USA
| | - Jogarao V. S. Gobburu
- Center for Translational Medicine, School of Pharmacy, University of Maryland, Baltimore, MD, USA
| | - John van den Anker
- Division of Clinical Pharmacology, Department of Pediatrics, Children’s National Hospital, George Washington University of School of Medicine and Health Sciences, Washington, DC, USA
| | - Bas de Laat
- Synapse Research Institute, Maastricht, The Netherlands
| | - Alisa S. Wolberg
- Department of Pathology and UNC Blood Research Center, University of North Carolina, Chapel Hill, NC, USA
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19
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Larsen JB, Hvas AM. Fibrin Clot Formation and Lysis in Plasma. Methods Protoc 2020; 3:mps3040067. [PMID: 32993011 PMCID: PMC7712220 DOI: 10.3390/mps3040067] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/21/2020] [Accepted: 09/23/2020] [Indexed: 12/20/2022] Open
Abstract
Disturbance in the balance between fibrin formation and fibrinolysis can lead to either bleeding or thrombosis; however, our current routine coagulation assays are not sensitive to altered fibrinolysis. The clot formation and lysis assay is a dynamic plasma-based analysis that assesses the patient’s capacity for fibrin formation and fibrinolysis by adding an activator of coagulation as well as fibrinolysis to plasma and measuring ex vivo fibrin clot formation and breakdown over time. This assay provides detailed information on the fibrinolytic activity but is currently used for research only, as the assay is prone to inter-laboratory variation and as it demands experienced laboratory technicians as well as specialized personnel to validate and interpret the results. Here, we describe a protocol for the clot formation and lysis assay used at our research laboratory.
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Affiliation(s)
- Julie Brogaard Larsen
- Thrombosis and Haemostasis Research Unit, Department of Clinical Biochemistry, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus, Denmark;
- Correspondence: ; Tel.: +45-4046-5766
| | - Anne-Mette Hvas
- Thrombosis and Haemostasis Research Unit, Department of Clinical Biochemistry, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus, Denmark;
- Department of Clinical Medicine, Health, Aarhus University, Palle Juul-Jensens Boulevard 82, 8200 Aarhus, Denmark
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20
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Ni R, Neves MAD, Wu C, Cerroni SE, Flick MJ, Ni H, Weitz JI, Gross PL, Kim PY. Activated thrombin-activatable fibrinolysis inhibitor (TAFIa) attenuates fibrin-dependent plasmin generation on thrombin-activated platelets. J Thromb Haemost 2020; 18:2364-2376. [PMID: 32506822 PMCID: PMC7719609 DOI: 10.1111/jth.14950] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 05/29/2020] [Accepted: 05/29/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Thrombin-activated platelets can promote fibrinolysis by binding plasminogen in a fibrinogen-dependent manner and enhancing its activation by tissue-type plasminogen activator (t-PA). Whether t-PA also binds to activated platelets and the mechanism for regulation of platelet-dependent fibrinolysis remain unknown. OBJECTIVES Determine the mechanism of plasminogen and t-PA binding on thrombin-activated platelets and its regulation by activated thrombin-activatable fibrinolysis inhibitor (TAFIa). METHODS Plasminogen and t-PA binding with or without TAFIa treatment was quantified using flow cytometry. Plasmin generation on platelets was quantified using a plasmin-specific substrate. Mass spectrometry analyses identified fibrinogen as a potential target of TAFIa. Thrombus formation was studied in mice lacking fibrinogen (Fg-/- ) using intravital microscopy. RESULTS Plasminogen and t-PA bind to platelets activated by thrombin but not by other agonists, including protease-activated receptor agonists (PAR-AP). Plasminogen binds via its kringle domains because ε-aminocaproic acid eliminates binding, whereas t-PA binds via its finger and kringle domains. Plasminogen binding is fibrinogen-dependent because it is abolished on (a) Fg-/- platelets, and (b) thrombi in Fg-/- mice. Binding requires thrombin-mediated fibrinogen modification because addition of batroxobin to PAR-AP activated platelets has no effect on plasminogen binding but induces t-PA binding. TAFIa reduces plasminogen and t-PA binding to thrombin-activated platelets and attenuates plasmin generation in a concentration-dependent manner. Mass spectrometry identified K556 on the fibrinogen alpha-chain as a potential thrombin cleavage site that generates a TAFIa sensitive C-terminal lysine residue. CONCLUSION These findings provide novel mechanistic insights into how platelets activated by thrombin at sites of vascular injury can influence fibrinolysis.
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Affiliation(s)
- Ran Ni
- Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada
- Departments of Medicine and Medical Sciences, McMaster University, Hamilton, ON, Canada
| | - Miguel A. D. Neves
- Department of Laboratory Medicine, Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto Platelet Immunobiology Group, Toronto, ON, Canada
| | - Chengliang Wu
- Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada
| | | | - Matthew J. Flick
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children’s Research Foundation, Cincinnati, OH, USA
| | - Heyu Ni
- Department of Laboratory Medicine, Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto Platelet Immunobiology Group, Toronto, ON, Canada
- Canadian Blood Services Centre for Innovation, Toronto, ON, Canada
- Department of Medicine and Physiology, University of Toronto, Toronto, ON, Canada
| | - Jeffrey I. Weitz
- Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada
- Departments of Medicine and Medical Sciences, McMaster University, Hamilton, ON, Canada
| | - Peter L. Gross
- Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada
- Departments of Medicine and Medical Sciences, McMaster University, Hamilton, ON, Canada
| | - Paul Y. Kim
- Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada
- Departments of Medicine and Medical Sciences, McMaster University, Hamilton, ON, Canada
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21
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Wu TB, Orfeo T, Moore HB, Sumislawski JJ, Cohen MJ, Petzold LR. Computational model of tranexamic acid on urokinase mediated fibrinolysis. PLoS One 2020; 15:e0233640. [PMID: 32453766 PMCID: PMC7250412 DOI: 10.1371/journal.pone.0233640] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 05/09/2020] [Indexed: 11/18/2022] Open
Abstract
Understanding the coagulation process is critical to developing treatments for trauma and coagulopathies. Clinical studies on tranexamic acid (TXA) have resulted in mixed reports on its efficacy in improving outcomes in trauma patients. The largest study, CRASH-2, reported that TXA improved outcomes in patients who received treatment prior to 3 hours after the injury, but worsened outcomes in patients who received treatment after 3 hours. No consensus has been reached about the mechanism behind the duality of these results. In this paper we use a computational model for coagulation and fibrinolysis to propose that deficiencies or depletions of key anti-fibrinolytic proteins, specifically antiplasmin, a1-antitrypsin and a2-macroglobulin, can lead to worsened outcomes through urokinase-mediated hyperfibrinolysis.
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Affiliation(s)
- Tie Bo Wu
- Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, California, United States of America
- * E-mail:
| | - Thomas Orfeo
- Department of Biochemistry, University of Vermont, Burlington, Vermont, United States of America
| | - Hunter B. Moore
- Department of Surgery, Denver Health and Hospital Authority, Denver, Colorado, United States of America
| | - Joshua J. Sumislawski
- Department of Surgery, Denver Health and Hospital Authority, Denver, Colorado, United States of America
| | - Mitchell J. Cohen
- Department of Surgery, Denver Health and Hospital Authority, Denver, Colorado, United States of America
| | - Linda R. Petzold
- Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, California, United States of America
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22
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Locke M, Longstaff C. How treatment delay may lead to loss of effectiveness of tranexamic acid. ANZ J Surg 2020; 90:416-418. [PMID: 32339423 DOI: 10.1111/ans.15669] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/27/2019] [Accepted: 12/05/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew Locke
- Division of Biotherapeutics, National Institute for Biological Standards and Control (NIBSC), Herts, UK
| | - Colin Longstaff
- Division of Biotherapeutics, National Institute for Biological Standards and Control (NIBSC), Herts, UK
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23
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Barrett CD, Yaffe MB. Influence of tranexamic acid on the complement system in trauma. ANZ J Surg 2020; 90:418-420. [DOI: 10.1111/ans.15538] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/02/2019] [Accepted: 10/03/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Christopher D. Barrett
- Koch InstituteMassachusetts Institute of Technology Cambridge Massachusetts USA
- Department of Surgery, Beth Israel Deaconess Medical CenterHarvard Medical School Boston Massachusetts USA
| | - Michael B. Yaffe
- Koch InstituteMassachusetts Institute of Technology Cambridge Massachusetts USA
- Department of Surgery, Beth Israel Deaconess Medical CenterHarvard Medical School Boston Massachusetts USA
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24
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Tranexamic acid is an active site inhibitor of urokinase plasminogen activator. Blood Adv 2020; 3:729-733. [PMID: 30814058 DOI: 10.1182/bloodadvances.2018025429] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 01/20/2019] [Indexed: 11/20/2022] Open
Abstract
Key Points
TXA is an active-site inhibitor of uPA. TXA attenuates MDA-MB-231 BAG cell migration and inhibits endogenous uPA activity.
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Li T, Yuan D, Yuan J. Antithrombotic Drugs-Pharmacology and Perspectives. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1177:101-131. [PMID: 32246445 DOI: 10.1007/978-981-15-2517-9_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Thrombosis, the localized clotting of blood that affects arterial or venous circulation, is one of the leading causes of death worldwide. Arterial thrombosis is commonly initiated by vascular endothelial injury, while venous thrombosis mainly stems from blood stasis. Despite these differences, platelet adhesion, activation and aggregation, and fibrin formation as a result of coagulation constitute the fundamental processes of thrombus formation. Antithrombotic drugs permitted on the clinical currently can dramatically reduce major adverse cardiovascular events; however, they can also increase the bleeding risk. Discovery of antithrombotic drugs that can effectively prevent thrombosis while sparing bleeding side effects remains unmet medical need. In this chapter, we provide an overview on the pathophysiology of thrombosis, followed by introduction of each class of antithrombotic drugs including their pharmacology, clinical applications and limitations. Practical challenges and future perspectives of antithrombotic drugs are discussed in the last part of this chapter.
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Affiliation(s)
- Tianyu Li
- Department of Cardiology, Fuwai Hospital, National Center of Cardiovascular Diseases, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Deshan Yuan
- Department of Cardiology, Fuwai Hospital, National Center of Cardiovascular Diseases, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Jinqing Yuan
- Department of Cardiology, Fuwai Hospital, National Center of Cardiovascular Diseases, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China.
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Cardenas JC. Mechanisms of Traumatic Hyperfibrinolysis and Implications for Antifibrinolytic Therapy. CURRENT TRAUMA REPORTS 2019. [DOI: 10.1007/s40719-019-00175-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tutwiler V, Peshkova AD, Le Minh G, Zaitsev S, Litvinov RI, Cines DB, Weisel JW. Blood clot contraction differentially modulates internal and external fibrinolysis. J Thromb Haemost 2019; 17:361-370. [PMID: 30582674 DOI: 10.1111/jth.14370] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Indexed: 01/16/2023]
Abstract
Essentials Clot contraction influences the rate of fibrinolysis in vitro. Internal fibrinolysis is enhanced ∼2-fold in contracted vs. uncontracted blood clots. External fibrinolysis is ∼4-fold slower in contracted vs. uncontracted blood clots. Contraction can modulate lytic resistance and potentially the clinical outcome of thrombosis. SUMMARY: Background Fibrinolysis involves dissolution of polymeric fibrin networks that is required to restore blood flow through vessels obstructed by thrombi. The efficiency of lysis depends in part on the susceptibility of fibrin to enzymatic digestion, which is governed by the structure and spatial organization of fibrin fibers. How platelet-driven clot contraction affects the efficacy of fibrinolysis has received relatively little study. Objective Here, we examined the effects of clot contraction on the rate of internal fibrinolysis emanating from within the clot to simulate (patho)physiological conditions and external fibrinolysis initiated from the clot exterior to simulate therapeutic thrombolysis. Methods Clot contraction was prevented by inhibiting platelet myosin IIa activity, actin polymerization or platelet-fibrin(ogen) binding. Internal fibrinolysis was measured by optical tracking of clot size. External fibrinolysis was determined by the release of radioactive fibrin degradation products. Results and Conclusions Clot contraction enhanced the rate of internal fibrinolysis ∼2-fold. In contrast, external fibrinolysis was ~4-fold slower in contracted clots. This dichotomy in the susceptibility of contracted and uncontracted clots to internal vs. external lysis suggests that the rate of lysis is dependent upon the interplay between accessibility of fibrin fibers to fibrinolytic agents, including clot permeability, and the spatial proximity of the fibrin fibers that modulate the effects of the fibrinolytic enzymes. Understanding how compaction of blood clots influences clot lysis might have important implications for prevention and treatment of thrombotic disorders.
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Affiliation(s)
- Valerie Tutwiler
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Alina D Peshkova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - Giang Le Minh
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - Sergei Zaitsev
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Rustem I Litvinov
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - Douglas B Cines
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - John W Weisel
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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Longstaff C, Locke M. Increased urokinase and consumption of α 2 -antiplasmin as an explanation for the loss of benefit of tranexamic acid after treatment delay. J Thromb Haemost 2019; 17:195-205. [PMID: 30451372 PMCID: PMC6334274 DOI: 10.1111/jth.14338] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Indexed: 12/26/2022]
Abstract
Essentials Delayed treatment with tranexamic acid results in loss of efficacy and poor outcomes. Increasing urokinase activity may account for adverse effects of late tranexamic acid treatment. Urokinase + tranexamic acid produces plasmin in plasma or blood and disrupts clotting. α2 -Antiplasmin consumption with ongoing fibrinolysis increases plasmin-induced coagulopathy. SUMMARY: Background Tranexamic acid (TXA) is an effective antifibrinolytic agent with a proven safety record. However, large clinical trials show TXA becomes ineffective or harmful if treatment is delayed beyond 3 h. The mechanism is unknown but urokinase plasminogen activator (uPA) has been implicated. Methods Inhibitory mechanisms of TXA were explored in a variety of clot lysis systems using plasma and whole blood. Lysis by tissue plasminogen activator (tPA), uPA and plasmin were investigated. Coagulopathy was investigated using ROTEM and activated partial thromboplastin time (APTT). Results IC50 values for antifibrinolytic activity of TXA varied from < 10 to > 1000 μmol L-1 depending on the system, but good fibrin protection was observed in the presence of tPA, uPA and plasmin. However, in plasma or blood, active plasmin was generated by TXA + uPA (but not tPA) and coagulopathy developed leading to no or poor clot formation. The extent of coagulopathy was sensitive to available α2 -antiplasmin. No clot formed with plasma containing 40% normal α2 -antiplasmin after short incubation with TXA + uPA. Adding purified α2 -antiplasmin progressively restored clotting. Plasmin could be inhibited by aprotinin, IC50 = 530 nmol L-1 , in plasma. Conclusions Tranexamic acid protects fibrin but stimulates uPA activity and slows inhibition of plasmin by α2 -antiplasmin. Plasmin proteolytic activity digests fibrinogen and disrupts coagulation, exacerbated when α2 -antiplasmin is consumed by ongoing fibrinolysis. Additional direct inhibition of plasmin by aprotinin may prevent development of coagulopathy and extend the useful time window of TXA treatment.
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Affiliation(s)
- C. Longstaff
- Biotherapeutics DivisionNational Institute for Biological Standards and ControlSouth MimmsUK
| | - M. Locke
- Biotherapeutics DivisionNational Institute for Biological Standards and ControlSouth MimmsUK
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Tranexamic acid mediates proinflammatory and anti-inflammatory signaling via complement C5a regulation in a plasminogen activator–dependent manner. J Trauma Acute Care Surg 2019; 86:101-107. [DOI: 10.1097/ta.0000000000002092] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Wyseure T, Cooke EJ, Declerck PJ, Behrendt N, Meijers JCM, von Drygalski A, Mosnier LO. Defective TAFI activation in hemophilia A mice is a major contributor to joint bleeding. Blood 2018; 132:1593-1603. [PMID: 30026184 PMCID: PMC6182268 DOI: 10.1182/blood-2018-01-828434] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 07/11/2018] [Indexed: 02/02/2023] Open
Abstract
Joint bleeds are common in congenital hemophilia but rare in acquired hemophilia A (aHA) for reasons unknown. To identify key mechanisms responsible for joint-specific bleeding in congenital hemophilia, bleeding phenotypes after joint injury and tail transection were compared in aHA wild-type (WT) mice (receiving an anti-factor VIII [FVIII] antibody) and congenital HA (FVIII-/-) mice. Both aHA and FVIII-/- mice bled severely after tail transection, but consistent with clinical findings, joint bleeding was notably milder in aHA compared with FVIII-/- mice. Focus was directed to thrombin-activatable fibrinolysis inhibitor (TAFI) to determine its potentially protective effect on joint bleeding in aHA. Joint bleeding in TAFI-/- mice with anti-FVIII antibody was increased, compared with WT aHA mice, and became indistinguishable from joint bleeding in FVIII-/- mice. Measurements of circulating TAFI zymogen consumption after joint injury indicated severely defective TAFI activation in FVIII-/- mice in vivo, consistent with previous in vitro analyses in FVIII-deficient plasma. In contrast, notable TAFI activation was observed in aHA mice, suggesting that TAFI protected aHA joints against bleeding. Pharmacological inhibitors of fibrinolysis revealed that urokinase-type plasminogen activator (uPA)-induced fibrinolysis drove joint bleeding, whereas tissue-type plasminogen activator-mediated fibrinolysis contributed to tail bleeding. These data identify TAFI as an important modifier of hemophilic joint bleeding in aHA by inhibiting uPA-mediated fibrinolysis. Moreover, our data suggest that bleed protection by TAFI was absent in congenital FVIII-/- mice because of severely defective TAFI activation, underscoring the importance of clot protection in addition to clot formation when considering prohemostatic strategies for hemophilic joint bleeding.
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Affiliation(s)
- Tine Wyseure
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA
| | - Esther J Cooke
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA
- Department of Medicine, University of California San Diego, San Diego, CA
| | - Paul J Declerck
- Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
| | - Niels Behrendt
- The Finsen Laboratory, Rigshospitalet/Biotech Research and Innovation Centre, University of Copenhagen, Copenhagen, Denmark
| | - Joost C M Meijers
- Department of Plasma Proteins, Sanquin Research, Amsterdam, The Netherlands; and
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Annette von Drygalski
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA
- Department of Medicine, University of California San Diego, San Diego, CA
| | - Laurent O Mosnier
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA
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Pryzdial ELG, Lee FMH, Lin BH, Carter RLR, Tegegn TZ, Belletrutti MJ. Blood coagulation dissected. Transfus Apher Sci 2018; 57:449-457. [PMID: 30049564 DOI: 10.1016/j.transci.2018.07.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Hemostasis is the physiological control of bleeding and is initiated by subendothelial exposure. Platelets form the primary vascular seal in three stages (localization, stimulation and aggregation), which are triggered by specific interactions between platelet surface receptors and constituents of the subendothelial matrix. As a secondary hemostatic plug, fibrin clot formation is initiated and feedback-amplified to advance the seal and stabilize platelet aggregates comprising the primary plug. Once blood leakage has been halted, the fibrinolytic pathway is initiated to dissolve the clot and restore normal blood flow. Constitutive and induced anticoagulant and antifibrinolytic pathways create a physiological balance between too much and too little clot production. Hemostatic imbalance is a major burden to global healthcare, resulting in thrombosis or hemorrhage.
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Affiliation(s)
- Edward L G Pryzdial
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada; Centre for Blood Research, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
| | - Frank M H Lee
- Centre for Blood Research, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Bryan H Lin
- Centre for Blood Research, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Rolinda L R Carter
- Centre for Blood Research, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Tseday Z Tegegn
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada; Centre for Blood Research, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Mark J Belletrutti
- Pediatric Hematology, Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
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Urano T, Castellino FJ, Suzuki Y. Regulation of plasminogen activation on cell surfaces and fibrin. J Thromb Haemost 2018; 16:S1538-7836(22)02204-8. [PMID: 29779246 PMCID: PMC6099326 DOI: 10.1111/jth.14157] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Indexed: 01/27/2023]
Abstract
The fibrinolytic system dissolves fibrin and maintains vascular patency. Recent advances in imaging analyses allowed visualization of the spatiotemporal regulatory mechanism of fibrinolysis, as well as its regulation by other plasma hemostasis cofactors. Vascular endothelial cells (VECs) retain tissue-type plasminogen activator (tPA) after secretion and maintain high plasminogen (plg) activation potential on their surfaces. As in plasma, the serpin, plasminogen activator inhibitor type 1 (PAI-1), regulates fibrinolytic potential via inhibition of the VEC surface-bound plg activator, tPA. Once fibrin is formed, plg activation by tPA is initiated and effectively amplified on the surface of fibrin, and fibrin is rapidly degraded. The specific binding of plg and tPA to lytic edges of partly degraded fibrin via newly generated C-terminal lysine residues, which amplifies fibrin digestion, is a central aspect of this pathophysiological mechanism. Thrombomodulin (TM) plays a role in the attenuation of plg binding on fibrin and the associated fibrinolysis, which is reversed by a carboxypeptidase B inhibitor. This suggests that the plasma procarboxypeptidase B, thrombin-activatable fibrinolysis inhibitor (TAFI), which is activated by thrombin bound to TM on VECs, is a critical aspect of the regulation of plg activation on VECs and subsequent fibrinolysis. Platelets also contain PAI-1, TAFI, TM, and the fibrin cross-linking enzyme, factor (F) XIIIa, and either secrete or expose these agents upon activation in order to regulate fibrinolysis. In this review, the native machinery of plg activation and fibrinolysis, as well as their spatiotemporal regulatory mechanisms, as revealed by imaging analyses, are discussed.
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Affiliation(s)
- T. Urano
- Department of Medical PhysiologyHamamatsu University School of MedicineHamamatsuJapan
| | - F. J. Castellino
- W.M. Keck Center for Transgene ResearchUniversity of Notre DameUniversity of Notre DameNotre DameINUSA
| | - Y. Suzuki
- Department of Medical PhysiologyHamamatsu University School of MedicineHamamatsuJapan
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Computational Model for Hyperfibrinolytic Onset of Acute Traumatic Coagulopathy. Ann Biomed Eng 2018; 46:1173-1182. [PMID: 29675813 DOI: 10.1007/s10439-018-2031-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 04/16/2018] [Indexed: 12/16/2022]
Abstract
The onset of acute traumatic coagulopathy in trauma patients exacerbates hemorrhaging and dramatically increases mortality. The disease is characterized by increased localized bleeding, and the mechanism for its onset is not yet known. We propose that the fibrinolytic response, specifically the release of tissue-plasminogen activator (t-PA), within vessels of different sizes leads to a variable susceptibility to local coagulopathy through hyperfibrinolysis which can explain many of the clinical observations in the early stages from severely injured coagulopathic patients. We use a partial differential equation model to examine the consequences of vessel geometry and extent of injury on fibrinolysis profiles. In addition, we simulate the efficacy of tranexamic acid treatment on coagulopathy initiated through endothelial t-PA release, and are able to reproduce the time-sensitive nature of the efficacy of this treatment as observed in clinical studies.
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Abstract
Development and standardization of fibrinolysis methods have progressed more slowly than coagulation testing and routine high-throughput screening tests for fibrinolysis are still lacking. In laboratory research, a variety of approaches are available and are applied to understand the regulation of fibrinolysis and its contribution to the hemostatic balance. Fibrinolysis in normal blood is slow to develop. For practical purposes plasminogen activators can be added to clotting plasma, or euglobulin prepared to reduce endogenous inhibitors, but results are complicated by these manipulations. Observational studies to identify a 'fibrinolysis deficit' have concluded that excess fibrinolysis inhibitors, plasminogen activator inhibitor 1 (PAI-1) or thrombin-activatable fibrinolysis inhibitor (TAFI), zymogen or active enzyme, may be associated with an increased risk of thrombosis. However, results are not always consistent and problems of adequate standardization are evident with these inhibitors and also for measurement of fibrin degradation products (D-dimer). Few methods are available to investigate fibrinolysis under flow, or in whole blood, but viscoelastic methods (VMs) such as ROTEM and TEG do permit the contribution of cells, and importantly platelets, to be explored. VMs are used to diagnose clinical hyperfibrinolysis, which is associated with high mortality. There is a debate on the usefulness of VMs as a point-of-care test method, particularly in trauma. Despite the difficulties of many fibrinolysis methods, research on the fibrinolysis system, taking in wider interactions with hemostasis proteins, is progressing so that in future we may have more complete models and better diagnostic methods and therapeutics.
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Affiliation(s)
- C. Longstaff
- Biotherapeutics DivisionNational Institute for Biological Standards and ControlSouth MimmsUK
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35
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Assumpção TC, Mizurini DM, Ma D, Monteiro RQ, Ahlstedt S, Reyes M, Kotsyfakis M, Mather TN, Andersen JF, Lukszo J, Ribeiro JMC, Francischetti IMB. Ixonnexin from Tick Saliva Promotes Fibrinolysis by Interacting with Plasminogen and Tissue-Type Plasminogen Activator, and Prevents Arterial Thrombosis. Sci Rep 2018; 8:4806. [PMID: 29555911 PMCID: PMC5859130 DOI: 10.1038/s41598-018-22780-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 02/22/2018] [Indexed: 12/11/2022] Open
Abstract
Tick saliva is a rich source of modulators of vascular biology. We have characterized Ixonnexin, a member of the "Basic-tail" family of salivary proteins from the tick Ixodes scapularis. Ixonnexin is a 104 residues (11.8 KDa), non-enzymatic basic protein which contains 3 disulfide bonds and a C-terminal rich in lysine. It is homologous to SALP14, a tick salivary FXa anticoagulant. Ixonnexin was produced by ligation of synthesized fragments (51-104) and (1-50) followed by folding. Ixonnexin, like SALP14, interacts with FXa. Notably, Ixonnexin also modulates fibrinolysis in vitro by a unique salivary mechanism. Accordingly, it accelerates plasminogen activation by tissue-type plasminogen activator (t-PA) with Km 100 nM; however, it does not affect urokinase-mediated fibrinolysis. Additionally, lysine analogue ε-aminocaproic acid inhibits Ixonnexin-mediated plasmin generation implying that lysine-binding sites of Kringle domain(s) of plasminogen or t-PA are involved in this process. Moreover, surface plasmon resonance experiments shows that Ixonnexin binds t-PA, and plasminogen (KD 10 nM), but not urokinase. These results imply that Ixonnexin promotes fibrinolysis by supporting the interaction of plasminogen with t-PA through formation of an enzymatically productive ternary complex. Finally, in vivo experiments demonstrates that Ixonnexin inhibits FeCl3-induced thrombosis in mice. Ixonnexin emerges as novel modulator of fibrinolysis which may also affect parasite-vector-host interactions.
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Affiliation(s)
- Teresa C Assumpção
- Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Bethesda, USA
| | - Daniella M Mizurini
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Dongying Ma
- Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Bethesda, USA
| | - Robson Q Monteiro
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Sydney Ahlstedt
- Department of Pathology, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY, USA
| | - Morayma Reyes
- Department of Pathology, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY, USA
| | - Michail Kotsyfakis
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Thomas N Mather
- Rhode Island Center for Vector-Borne Disease, University of Rhode Island, Kingston, Rhode Island, USA
| | - John F Andersen
- Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Bethesda, USA
| | - Jan Lukszo
- Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Bethesda, USA
| | - José M C Ribeiro
- Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Bethesda, USA
| | - Ivo M B Francischetti
- Laboratory of Malaria and Vector Research, NIAID, National Institutes of Health, Bethesda, USA.
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Abstract
We all know about classical fibrinolysis, how plasminogen activation by either tissue-type plasminogen activator (t-PA) or urokinase-type plasminogen activator (u-PA) promotes fibrin breakdown, and how this process was harnessed for the therapeutic removal of blood clots. While this is still perfectly true and still applicable to thromboembolic conditions today, another dimension to this system came to light over two decades ago that implicated the plasminogen activating system in a context far removed from the dissolution of blood clots. This unsuspected area related to brain biology where t-PA was linked to a plethora of activities in the CNS, some of which do not necessarily require plasmin generation. Indeed, t-PA either directly or via plasmin, has been shown to not only have key roles in modulating astrocytes, neurons, microglia, and pericytes, but also to have profound effects in a number of CNS conditions, including ischaemic stroke, severe traumatic brain injury and also in neurodegenerative disorders. While compelling insights have been obtained from various animal models, the clinical relevance of aberrant expression of these components in the CNS, although strongly implied, are only just emerging. This review will cover these areas and will also discuss how the use of thrombolytic agents and anti-fibrinolytic drugs may potentially have impacts outside of their clinical intention, particularly in the CNS.
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Affiliation(s)
- R L Medcalf
- Australian Centre for Blood Diseases, Monash University, Melbourne, Vic, Australia
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37
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Maegele M, Schöchl H, Menovsky T, Maréchal H, Marklund N, Buki A, Stanworth S. Coagulopathy and haemorrhagic progression in traumatic brain injury: advances in mechanisms, diagnosis, and management. Lancet Neurol 2017; 16:630-647. [PMID: 28721927 DOI: 10.1016/s1474-4422(17)30197-7] [Citation(s) in RCA: 189] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 05/08/2017] [Accepted: 05/30/2017] [Indexed: 01/28/2023]
Abstract
Normal haemostasis depends on an intricate balance between mechanisms of bleeding and mechanisms of thrombosis, and this balance can be altered after traumatic brain injury (TBI). Impaired haemostasis could exacerbate the primary insult with risk of initiation or aggravation of bleeding; anticoagulant use at the time of injury can also contribute to bleeding risk after TBI. Many patients with TBI have abnormalities on conventional coagulation tests at admission to the emergency department, and the presence of coagulopathy is associated with increased morbidity and mortality. Further blood testing often reveals a range of changes affecting platelet numbers and function, procoagulant or anticoagulant factors, fibrinolysis, and interactions between the coagulation system and the vascular endothelium, brain tissue, inflammatory mechanisms, and blood flow dynamics. However, the degree to which these coagulation abnormalities affect TBI outcomes and whether they are modifiable risk factors are not known. Although the main challenge for management is to address the risk of hypocoagulopathy with prolonged bleeding and progression of haemorrhagic lesions, the risk of hypercoagulopathy with an increased prothrombotic tendency also warrants consideration.
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Affiliation(s)
- Marc Maegele
- Department for Trauma and Orthopaedic Surgery, Cologne-Merheim Medical Center, University Witten/Herdecke, Cologne, Germany; Institute for Research in Operative Medicine, University Witten/Herdecke, Cologne, Germany.
| | - Herbert Schöchl
- Department for Anaesthesiology and Intensive Care Medicine, AUVA Trauma Academic Teaching Hospital, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Tomas Menovsky
- Department for Neurosurgery, Antwerp University Hospital, University of Antwerp, Edegem, Belgium
| | - Hugues Maréchal
- Department of Anaesthesiology and Intensive Care Medicine, CRH La Citadelle, Liège, Belgium
| | - Niklas Marklund
- Department of Clinical Sciences, Division of Neurosurgery, University Hospital of Southern Sweden, Lund University, Lund, Sweden
| | - Andras Buki
- Department of Neurosurgery, The MTA-PTE Clinical Neuroscience MR Research Group, Janos Szentagothai Research Center, Hungarian Brain Research Program, University of Pécs, Pécs, Hungary
| | - Simon Stanworth
- NHS Blood and Transplant/Oxford University Hospitals NHS Foundation Trust, University of Oxford, John Radcliffe Hospital, Oxford, UK
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Moore EE, Moore HB, Gonzalez E, Sauaia A, Banerjee A, Silliman CC. Rationale for the selective administration of tranexamic acid to inhibit fibrinolysis in the severely injured patient. Transfusion 2017; 56 Suppl 2:S110-4. [PMID: 27100746 DOI: 10.1111/trf.13486] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 11/30/2015] [Indexed: 12/12/2022]
Abstract
Postinjury fibrinolysis can manifest as three distinguishable phenotypes: 1) hyperfibrinolysis, 2) physiologic, and 3) hypofibrinolysis (shutdown). Hyperfibrinolysis is associated with uncontrolled bleeding due to clot dissolution; whereas, fibrinolysis shutdown is associated with organ dysfunction due to microvascular occlusion. The incidence of fibrinolysis phenotypes at hospital arrival in severely injured patients is: 1) hyperfibrinolysis 18%, physiologic 18%, and shutdown 64%. The mechanisms responsible for dysregulated fibrinolysis following injury remain uncertain. Animal work suggests hypoperfusion promotes fibrinolysis, while tissue injury inhibits fibrinolysis. Clinical experience is consistent with these observations. The predominant mediator of postinjury hyperfibrinolysis appears to be tissue plasminogen activator (tPA) released from ischemic endothelium. The effects of tPA are accentuated by impaired hepatic clearance. Fibrinolysis shutdown, on the other hand, may occur from inhibition of circulating tPA, enhanced clot strength impairing the binding of tPA and plasminogen to fibrin, or the inhibition of plasmin. Plasminogen activator inhibitor -1 (PAI-1) binding of circulating tPA appears to be a major mechanism for postinjury shutdown. The sources of PAI-1 include endothelium, platelets, and organ parenchyma. The laboratory identification of fibrinolysis phenotype, at this moment, is best determined with viscoelastic hemostatic assays (TEG, ROTEM). While D-dimer and plasmin antiplasmin (PAP) levels corroborate fibrinolysis, they do not provide real-time assessment of the circulating blood capacity. Our clinical studies indicate that fibrinolysis is a very dynamic process and our experimental work suggests plasma first resuscitation reverses hyperfibrinolysis. Collectively, we believe recent clinical and experimental work suggest antifibrinolytic therapy should be employed selectively in the acutely injured patient, and optimally guided by TEG or ROTEM.
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Affiliation(s)
- Ernest E Moore
- Denver Health Medical Center, Bonfils Blood Center, Denver, Colorado.,Department of Surgery, University of Colorado, Denver, Colorado
| | - Hunter B Moore
- Denver Health Medical Center, Bonfils Blood Center, Denver, Colorado.,Department of Surgery, University of Colorado, Denver, Colorado
| | - Eduardo Gonzalez
- Denver Health Medical Center, Bonfils Blood Center, Denver, Colorado.,Department of Surgery, University of Colorado, Denver, Colorado
| | - Angela Sauaia
- Denver Health Medical Center, Bonfils Blood Center, Denver, Colorado.,Department of Surgery, University of Colorado, Denver, Colorado
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Hudson NE. Biophysical Mechanisms Mediating Fibrin Fiber Lysis. BIOMED RESEARCH INTERNATIONAL 2017; 2017:2748340. [PMID: 28630861 PMCID: PMC5467299 DOI: 10.1155/2017/2748340] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 04/30/2017] [Indexed: 01/19/2023]
Abstract
The formation and dissolution of blood clots is both a biochemical and a biomechanical process. While much of the chemistry has been worked out for both processes, the influence of biophysical properties is less well understood. This review considers the impact of several structural and mechanical parameters on lytic rates of fibrin fibers. The influences of fiber and network architecture, fiber strain, FXIIIa cross-linking, and particle transport phenomena will be assessed. The importance of the mechanical aspects of fibrinolysis is emphasized, and future research avenues are discussed.
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Affiliation(s)
- Nathan E. Hudson
- Department of Physics, East Carolina University, N304 Howell Science Complex, Greenville, NC 27858, USA
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40
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Miller VA, Madureira PA, Kamaludin AA, Komar J, Sharma V, Sahni G, Thelwell C, Longstaff C, Waisman DM. Mechanism of plasmin generation by S100A10. Thromb Haemost 2017; 117:1058-1071. [PMID: 28382372 DOI: 10.1160/th16-12-0936] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 03/19/2017] [Indexed: 12/21/2022]
Abstract
Plasminogen (Pg) is cleaved to form plasmin by the action of specific plasminogen activators such as the tissue plasminogen activator (tPA). Although the interaction of tPA and Pg with the surface of the fibrin clot has been well characterised, their interaction with cell surface Pg receptors is poorly understood. S100A10 is a cell surface Pg receptor that plays a key role in cellular plasmin generation. In the present report, we have utilised domain-switched/deleted variants of tPA, truncated plasminogen variants and S100A10 site-directed mutant proteins to define the regions responsible for S100A10-dependent plasmin generation. In contrast to the established role of the finger domain of tPA in fibrin-stimulated plasmin generation, we show that the kringle-2 domain of tPA plays a key role in S100A10-dependent plasmin generation. The kringle-1 domain of plasminogen, indispensable for fibrin-binding, is also critical for S100A10-dependent plasmin generation. S100A10 retains activity after substitution or deletion of the carboxyl-terminal lysine suggesting that internal lysine residues contribute to its plasmin generating activity. These studies define a new paradigm for plasminogen activation by the plasminogen receptor, S100A10.
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Affiliation(s)
| | | | | | | | | | | | | | | | - David M Waisman
- David M. Waisman*, Departments of Biochemistry & Molecular Biology and Pathology, Sir Charles Tupper Medical Building, 5850 College Street, room 11-N2, PO Box 15000, Dalhousie University, Halifax, Nova Scotia, B3H 4R2, Canada, Tel.: +1 902 494 1803, Fax: +1 902 494 1355, E-mail:
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41
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Roberts I, Edwards P, Prieto D, Joshi M, Mahmood A, Ker K, Shakur H. Tranexamic acid in bleeding trauma patients: an exploration of benefits and harms. Trials 2017; 18:48. [PMID: 28143564 PMCID: PMC5282847 DOI: 10.1186/s13063-016-1750-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 12/08/2016] [Indexed: 12/12/2022] Open
Abstract
Background The CRASH-2 trial showed that tranexamic acid (TXA) administration reduces mortality in bleeding trauma patients. However, the effect appeared to depend on how soon after injury TXA treatment was started. Treatment within 3 h reduced bleeding deaths whereas treatment after 3 h increased the risk. We examine how patient characteristics vary by time to treatment and explore whether any such variations explain the time-dependent treatment effect. Methods Exploratory analysis were carried out, including per-protocol analyses, of data from the CRASH-2 trial, a randomised placebo-controlled trial of the effect of TXA on mortality in 20,211 trauma patients with, or at risk of, significant bleeding. We examine how patient characteristics (age, type of injury, presence or absence of head injury, Glasgow coma scale (GCS), systolic blood pressure and capillary refill time) vary with time to treatment and use univariable (restriction) and multivariable methods to examine whether any such variations explain the time-dependent effect of TXA. If not explained by differences in patient characteristics, we planned to conduct separate prespecified subgroup analyses for the early benefit and late harm. Results There was no substantial variation in age or capillary refill by time to treatment. However, the proportion of patients with blunt trauma, the proportion with head injury and mean systolic blood pressure increased as time to treatment increased. Mean GCS decreased as time to treatment increased. Analyses restricted to patients with blunt trauma, those without head injury and those with a systolic blood pressure <100 mmHg showed that these characteristics did not explain the time-dependent treatment effect. In a multivariable analysis the interaction with time to treatment remained highly significant (p < 0.0001). Separate subgroup analyses that examine how the benefits of early TXA treatment and the harms of late TXA treatment vary by systolic blood pressure (≤75, 76–89, >89 mmHg); GCS (severe 3–8, moderate 9–12, mild 13–15); and type of injury (penetrating versus blunt) showed no significant heterogeneity. Conclusions The time-dependent effect of TXA in bleeding trauma patients is not explained by the type of injury, the presence or absence of head injury or systolic blood pressure. When given within 3 h of injury, TXA reduces death due to bleeding regardless of type of injury, GCS or blood pressure. Trial registration ClinicalTrials.gov, NCT00375258. Registered on 11 September 2006. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1750-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ian Roberts
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Phil Edwards
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - David Prieto
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,Catholic University of Murcia, Murcia, Spain
| | - Miland Joshi
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Abda Mahmood
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Katharine Ker
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Haleema Shakur
- Clinical Trials Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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42
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Huish S, Thelwell C, Longstaff C. Activity Regulation by Fibrinogen and Fibrin of Streptokinase from Streptococcus Pyogenes. PLoS One 2017; 12:e0170936. [PMID: 28125743 PMCID: PMC5268773 DOI: 10.1371/journal.pone.0170936] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 01/12/2017] [Indexed: 01/26/2023] Open
Abstract
Streptokinase is a virulence factor of streptococci and acts as a plasminogen activator to generate the serine protease plasmin which promotes bacterial metastasis. Streptokinase isolated from group C streptococci has been used therapeutically as a thrombolytic agent for many years and its mechanism of action has been extensively studied. However, group A streptococci are associated with invasive and potentially fatal infections, but less detail is available on the mechanism of action of streptokinase from these bacteria. We have expressed recombinant streptokinase from a group C strain to investigate the therapeutic molecule (here termed rSK-H46A) and a molecule isolated from a cluster 2a strain from group A (rSK-M1GAS) which is known to produce the fibrinogen binding, M1 protein, and is associated with life-threatening disease. Detailed enzyme kinetic models have been prepared which show how fibrinogen-streptokinase-plasminogen complexes regulate plasmin generation, and also the effect of fibrin interactions. As is the case with rSK-H46A our data with rSK-M1GAS support a "trigger and bullet" mechanism requiring the initial formation of SK•plasminogen complexes which are replaced by more active SK•plasmin as plasmin becomes available. This model includes the important fibrinogen interactions that stimulate plasmin generation. In a fibrin matrix rSK-M1GAS has a 24 fold higher specific activity than the fibrin-specific thrombolytic agent, tissue plasminogen activator, and 15 fold higher specific activity than rSK-H46A. However, in vivo fibrin specificity would be undermined by fibrinogen stimulation. Given the observed importance of M1 surface receptors or released M1 protein to virulence of cluster 2a strain streptococci, studies on streptokinase activity regulation by fibrin and fibrinogen may provide additional routes to addressing bacterial invasion and infectious diseases.
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Affiliation(s)
- Sian Huish
- Component development laboratory, NHS Blood and Transplant, Cambridge Donor Centre, Cambridge, United Kingdom
| | - Craig Thelwell
- Biotherapeutics Section, National Institute for Biological Standard and Control, South Mimms, Herts, United Kingdom
| | - Colin Longstaff
- Biotherapeutics Section, National Institute for Biological Standard and Control, South Mimms, Herts, United Kingdom
- * E-mail:
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43
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Pryzdial ELG, Meixner SC, Talbot K, Eltringham-Smith LJ, Baylis JR, Lee FMH, Kastrup CJ, Sheffield WP. Thrombolysis by chemically modified coagulation factor Xa. J Thromb Haemost 2016; 14:1844-54. [PMID: 27359348 PMCID: PMC5576980 DOI: 10.1111/jth.13402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 06/15/2016] [Indexed: 12/22/2022]
Abstract
UNLABELLED Essentials Factor Xa (FXa) acquires cleavage-mediated tissue plasminogen activator (tPA) cofactor activity. Recombinant (r) tPA is the predominant thrombolytic drug, but it may cause systemic side effects. Chemically modified, non-enzymatic FXa was produced (Xai-K), which rapidly lysed thrombi in mice. Unlike rtPA, Xai-K had no systemic fibrinolysis activation markers, indicating improved safety. SUMMARY Background Enzymatic thrombolysis carries the risk of hemorrhage and re-occlusion must be evaded by co-administration with an anticoagulant. Toward further improving these shortcomings, we report a novel dual-functioning molecule, Xai-K, which is both a non-enzymatic thrombolytic agent and an anticoagulant. Xai-K is based on clotting factor Xa, whose sequential plasmin-mediated fragments, FXaβ and Xa33/13, accelerate the principal thrombolytic agent, tissue plasminogen activator (tPA), but only when localized to anionic phospholipid. Methods The effect of Xai-K on fibrinolysis was measured in vitro by turbidity, thromboelastography and chromogenic assays, and measured in a murine model of occlusive carotid thrombosis by Doppler ultrasound. The anticoagulant properties of Xai-K were evaluated by normal plasma clotting assays, and in murine liver laceration and tail amputation hemostatic models. Results Xa33/13, which participates in fibrinolysis of purified fibrin, was rapidly inhibited in plasma. Cleavage was blocked at FXaβ by modifying residues at the active site. The resultant Xai-K (1 nm) enhanced plasma clot dissolution by ~7-fold in vitro and was dependent on tPA. Xai-K alone (2.0 μg g(-1) body weight) achieved therapeutic patency in mice. The minimum primary dose of the tPA variant, Tenecteplase (TNK; 17 μg g(-1) ), could be reduced by > 30-fold to restore blood flow with adjunctive Xai-K (0.5 μg g(-1) ). TNK-induced systemic markers of fibrinolysis were not detected with Xai-K (2.0 μg g(-1) ). Xai-K had anticoagulant activity that was somewhat attenuated compared with a previously reported analogue. Conclusion These results suggest that Xai-K may ameliorate the safety profile of therapeutic thrombolysis, either as a primary or tPA/TNK-adjunctive agent.
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Affiliation(s)
- E L G Pryzdial
- Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada.
| | - S C Meixner
- Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada
| | - K Talbot
- Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada
| | - L J Eltringham-Smith
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - J R Baylis
- Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Michael Smith Laboratories and Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - F M H Lee
- Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada
| | - C J Kastrup
- Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Michael Smith Laboratories and Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - W P Sheffield
- Centre for Innovation, Canadian Blood Services, Ottawa, ON, Canada
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
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44
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Kylväjä R, Ojalehto T, Kainulainen V, Virkola R, Westerlund-Wikström B. Penicillin binding protein 3 of Staphylococcus aureus NCTC 8325-4 binds and activates human plasminogen. BMC Res Notes 2016; 9:389. [PMID: 27488131 PMCID: PMC4972960 DOI: 10.1186/s13104-016-2190-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 07/28/2016] [Indexed: 11/25/2022] Open
Abstract
Background Staphylococcus aureus is a versatile pathogen expressing a number of virulence-associated adhesive molecules. In a previous study, we generated in a secretion-competent Escherichia coli strain a library of random FLAG-tag positive (FTP) polypeptides of S. aureus. To identify adhesive proteins and gain additional knowledge on putative virulence factors of S. aureus, we here screened the FTP library against human serum proteins. Findings Staphylococcus aureus NCTC 8325-4, origin of the FTP library, adhered to immobilized plasminogen in vitro. In an enzyme-linked immunoassay a C-terminal part of penicillin binding protein 3 (PBP3), included in the FTP library, bound to immobilized plasminogen. We expressed and purified full-length PBP3 and its C-terminal fragments as recombinant proteins. In a time-resolved fluorometry—based assay the PBP3 polypeptides bound to immobilized plasminogen. The polypeptides enhanced formation of plasmin from plasminogen as analyzed by cleavage of a chromogenic plasmin substrate. Conclusions The present findings, although preliminary, demonstrate reliably that S. aureus NCTC 8325-4 adheres to immobilized plasminogen in vitro and that the adhesion may be mediated by a C-terminal fragment of the PBP3 protein. The full length PBP3 and the penicillin binding C-terminal domain of PBP3 expressed as recombinant proteins bound plasminogen and activated plasminogen to plasmin. These phenomena were inhibited by the lysine analogue ε-aminocaproic acid suggesting that the binding is mediated by lysine residues. A detailed molecular description of surface molecules enhancing the virulence of S. aureus will aid in understanding of its pathogenicity and help in design of antibacterial drugs in the future. Electronic supplementary material The online version of this article (doi:10.1186/s13104-016-2190-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Riikka Kylväjä
- General Microbiology, Department of Biosciences, University of Helsinki, P.O.Box 56, FI-00014, University of Helsinki, Helsinki, Finland.,Thermo Fisher Scientific, Ratastie 2, 01620, Vantaa, Finland
| | - Tuomas Ojalehto
- General Microbiology, Department of Biosciences, University of Helsinki, P.O.Box 56, FI-00014, University of Helsinki, Helsinki, Finland.,Orion Diagnostica, Koivu-Mankkaan tie 6, 02200, Espoo, Finland
| | - Veera Kainulainen
- General Microbiology, Department of Biosciences, University of Helsinki, P.O.Box 56, FI-00014, University of Helsinki, Helsinki, Finland.,Pharmacology, Faculty of Medicine, University of Helsinki, P.O.Box 63, FI-00014, University of Helsinki, Helsinki, Finland
| | - Ritva Virkola
- General Microbiology, Department of Biosciences, University of Helsinki, P.O.Box 56, FI-00014, University of Helsinki, Helsinki, Finland
| | - Benita Westerlund-Wikström
- General Microbiology, Department of Biosciences, University of Helsinki, P.O.Box 56, FI-00014, University of Helsinki, Helsinki, Finland.
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45
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Abstract
The components and reactions of the fibrinolysis system are well understood. The pathway has fewer reactants and interactions than coagulation, but the generation of a complete quantitative model is complicated by the need to work at the solid‐liquid interface of fibrin. Diagnostic tools to detect disease states due to malfunctions in the fibrinolysis pathway are also not so well developed as is the case with coagulation. However, there are clearly a number of inherited or acquired pathologies where hyperfibrinolysis is a serious, potentially life‐threatening problem and a number of antifibrinolytc drugs are available to treat hyperfibrinolysis. These topics will be covered in the following review.
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Affiliation(s)
- Krasimir Kolev
- Department of Medical Biochemistry, Semmelweis University, Budapest, Hungary
| | - Colin Longstaff
- Biotherapeutics Group, National Institute for Biological Standards and Control, South Mimms, UK.
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46
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Godier A, Parmar K, Manandhar K, Hunt BJ. An in vitro study of the effects of t-PA and tranexamic acid on whole blood coagulation and fibrinolysis. J Clin Pathol 2016; 70:154-161. [PMID: 27445340 DOI: 10.1136/jclinpath-2016-203854] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 06/23/2016] [Accepted: 06/27/2016] [Indexed: 11/03/2022]
Abstract
AIMS Acute traumatic coagulopathy is characterised by fibrinolysis and low fibrinogen. It is unclear how much fibrinogenolysis contributes to reduce fibrinogen levels. The study aim was to: investigate in vitro the effects of tissue-plasminogen activator (t-PA) and tranexamic acid (TXA) on coagulation and fibrinolysis. METHODS Whole blood was spiked with varying t-PA concentrations. Clauss fibrinogen levels and thrombelastography (TEG, Haemonetics) were performed, including functional fibrinogen level (FLEV). TXA effects were assessed using four TXA concentrations. Recorded parameters from kaolin activated TEG included maximal amplitude (MA), clot strength (G), percentage lysis (LY). Plasmin-antiplasmin complex (PAP), endogenous thrombin potential (ETP), prothrombin fragment 1+2 (PF1+2), factor V and factor VIII levels were all measured. RESULTS t-PA induced fibrinolysis: it increased PAP and LY, but decreased MA and G. t-PA induced fibrinogenolysis, with a concentration-dependant decrease in fibrinogen from 2.7 (2.6-3.1) to 0.8 (0.8-0.9) g/L with 60 nM t-PA. FLEV and fibrinogen levels were well correlated. High t-PA doses increased PF1+2, decreased ETP of 19% and FVIII of 63% but not FV. TXA had no effect on plasmin generation as evidenced by no change in PAP. It corrected LY, MA and G and partly protected fibrinogen against fibrinogenolysis: 0.03 mg/mL TXA reduced the fibrinogen fall induced by t-PA 20 nM from 43% to 14%. TXA halved the FVIII fall and increased ETP. CONCLUSIONS t-PA induced plasminogen activation and fibrinogenolysis in a concentration-dependant manner. TXA did not affect plasmin activation but reduced fibrinogenolysis. These results suggest that TXA given early in bleeding patients may prevent fibrinogenolysis.
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Affiliation(s)
- Anne Godier
- Department of Anesthesia and Critical Care, Fondation Ophtalmologique Rothschild, Paris, France.,Faculté de Pharmacie, INSERM UMR-S1140, Université Paris Descartes, Paris, France.,Department of Thrombosis and Vascular Biology, Rayne Institute, London, UK
| | - Kiran Parmar
- Department of Thrombosis and Vascular Biology, Rayne Institute, London, UK
| | - Karuna Manandhar
- Department of Thrombosis and Vascular Biology, Rayne Institute, London, UK
| | - Beverley J Hunt
- Department of Thrombosis and Vascular Biology, Rayne Institute, London, UK.,Thrombosis and Haemostasis Centre, Guy's and St Thomas's NHS Foundation Trusts, and King's College, London, UK
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47
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Sawhney P, Katare K, Sahni G. PEGylation of Truncated Streptokinase Leads to Formulation of a Useful Drug with Ameliorated Attributes. PLoS One 2016; 11:e0155831. [PMID: 27192220 PMCID: PMC4871584 DOI: 10.1371/journal.pone.0155831] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 05/04/2016] [Indexed: 12/31/2022] Open
Abstract
Streptokinase (SK) remains a favored thrombolytic agent in the developing world as compared to the nearly 10-fold more expensive human tissue-plasminogen activator (tPA) for the dissolution of pathological fibrin clots in myocardial infarction. However, unlike the latter, SK induces systemic activation of plasmin which results in a greater risk of hemorrhage. Being of bacterial origin, it elicits generation of unwanted antibody and has a relatively short half-life in vivo that needs to be addressed to make it more efficacious clinically. In order to address these lacunae, in the present study we have incorporated cysteine residues specifically at the N- and C-termini of partially truncated SK and these were then PEGylated successfully. Some of the obtained derivatives displayed enhanced plasmin resistance, longer half-life (upto several hours), improved fibrin clot-specificity and reduced immune-reactivity as compared to the native SK (nSK). This paves the way for devising next-generation SK-based thrombolytic agent/s that besides being fibrin clot-specific are endowed with an improved efficacy by virtue of an extended in vivo half-life.
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Affiliation(s)
- Pooja Sawhney
- Department of Molecular Biology and Protein Science and Engineering, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
| | - Keya Katare
- Department of Molecular Biology and Protein Science and Engineering, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
| | - Girish Sahni
- Department of Molecular Biology and Protein Science and Engineering, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
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48
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Abstract
In this issue of Blood, Hijazi et al challenge the view that consumptive coagulopathy that accompanies traumatic brain injury (TBI) results in a sequence of events that lead to intracranial hemorrhage (ICH).
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49
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Abstract
Fibrinolysis appears in many diverse physiological situations, and the components of the system are well established, along with mechanistic details for the individual reactions and some high-resolution structures. Key questions in understanding the regulation of fibrinolysis surround mechanisms of initiation and propagation, the localization of fibrinolysis reactions to the fibrin clot, and the influence of fibrin structure and clot composition on thrombolysis. This review covers these key areas with a focus on recent developments on fibrin structure and binding, the effects of a variety of cell types, the consequences of histones and DNA released by neutrophils, and the influence of flow. A complete understanding of the regulation of fibrinolysis will come from the building of detailed mathematical models. Suitable models are at an early stage of development, but may improve as model clots increase in complexity to incorporate the components and interactions listed above.
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Affiliation(s)
- C Longstaff
- Biotherapeutics, Haemostasis Section, National Institute for Biological Standards and Control, South Mimms, Potters Bar, UK
| | - K Kolev
- Department of Medical Biochemistry, Semmelweis University, Budapest, Hungary
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50
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Endogenous plasminogen activators mediate progressive intracerebral hemorrhage after traumatic brain injury in mice. Blood 2015; 125:2558-67. [PMID: 25673638 DOI: 10.1182/blood-2014-08-588442] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 01/15/2015] [Indexed: 12/11/2022] Open
Abstract
Persistent intracerebral hemorrhage (ICH) is a major cause of death and disability after traumatic brain injury (TBI) for which no medical treatment is available. Delayed bleeding is often ascribed to consumptive coagulopathy initiated by exposed brain tissue factor. We examined an alternative hypothesis, namely, that marked release of tissue-type plasminogen activator (tPA) followed by delayed synthesis and release of urokinase plasminogen activator (uPA) from injured brain leads to posttraumatic bleeding by causing premature clot lysis. Using a murine model of severe TBI, we found that ICH is reduced in tPA(-/-) and uPA(-/-) mice but increased in PAI-1(-/-) mice compared with wild-type (WT) mice. tPA(-/-), but not uPA(-/-), mice developed a systemic coagulopathy post-TBI. Tranexamic acid inhibited ICH expansion in uPA(-/-)mice but not in tPA(-/-) mice. Catalytically inactive tPA-S(481)A inhibited plasminogen activation by tPA and uPA, attenuated ICH, lowered plasma d-dimers, lessened thrombocytopenia, and improved neurologic outcome in WT, tPA(-/-), and uPA(-/-) mice. ICH expansion was also inhibited by tPA-S(481)A in WT mice anticoagulated with warfarin. These data demonstrate that protracted endogenous fibrinolysis induced by TBI is primarily responsible for persistent ICH and post-TBI coagulopathy in this model and offer a novel approach to interrupt bleeding.
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