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Morrow GB, Mutch NJ. Removing plasmin from the equation - Something to chew on…. J Thromb Haemost 2022; 20:280-284. [PMID: 34816576 DOI: 10.1111/jth.15590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 11/08/2021] [Accepted: 11/10/2021] [Indexed: 11/29/2022]
Affiliation(s)
- Gael B Morrow
- Aberdeen Cardiovascular & Diabetes Centre, Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Nicola J Mutch
- Aberdeen Cardiovascular & Diabetes Centre, Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
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Tilvawala R, Nemmara VV, Reyes AC, Sorvillo N, Salinger AJ, Cherpokova D, Fukui S, Gutch S, Wagner D, Thompson PR. The role of SERPIN citrullination in thrombosis. Cell Chem Biol 2021; 28:1728-1739.e5. [PMID: 34352225 DOI: 10.1016/j.chembiol.2021.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 04/29/2021] [Accepted: 07/08/2021] [Indexed: 02/01/2023]
Abstract
Aberrant protein citrullination is associated with many pathologies; however, the specific effects of this modification remain unknown. We have previously demonstrated that serine protease inhibitors (SERPINs) are highly citrullinated in rheumatoid arthritis (RA) patients. These citrullinated SERPINs include antithrombin, antiplasmin, and t-PAI, which regulate the coagulation and fibrinolysis cascades. Notably, citrullination eliminates their inhibitory activity. Here, we demonstrate that citrullination of antithrombin and t-PAI impairs their binding to their cognate proteases. By contrast, citrullination converts antiplasmin into a substrate. We recapitulate the effects of SERPIN citrullination using in vitro plasma clotting and fibrinolysis assays. Moreover, we show that citrullinated antithrombin and antiplasmin are increased and decreased in a deep vein thrombosis (DVT) model, accounting for how SERPIN citrullination shifts the equilibrium toward thrombus formation. These data provide a direct link between increased citrullination and the risk of thrombosis in autoimmunity and indicate that aberrant SERPIN citrullination promotes pathological thrombus formation.
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Affiliation(s)
- Ronak Tilvawala
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA; Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Venkatesh V Nemmara
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA; Department of Chemistry, Rowan University, Glassboro, NJ 08028, USA
| | - Archie C Reyes
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA
| | - Nicoletta Sorvillo
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Ari J Salinger
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA; Department of Chemistry, Boston College, Chestnut Hill, MA 02467, USA
| | - Deya Cherpokova
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Saeko Fukui
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Sarah Gutch
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Denisa Wagner
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA; Whitman Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Paul R Thompson
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA.
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Singh S, Saleem S, Reed GL. Alpha2-Antiplasmin: The Devil You Don't Know in Cerebrovascular and Cardiovascular Disease. Front Cardiovasc Med 2020; 7:608899. [PMID: 33426005 PMCID: PMC7785519 DOI: 10.3389/fcvm.2020.608899] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 12/02/2020] [Indexed: 01/23/2023] Open
Abstract
Alpha2-antiplasmin (α2AP), the fast-reacting, serine protease inhibitor (serpin) of plasmin, was originally thought to play a key role in protection against uncontrolled, plasmin-mediated proteolysis of coagulation factors and other molecules. However, studies of humans and mice with genetic deficiency of α2AP have expanded our understanding of this serpin, particularly in disease states. Epidemiology studies have shown an association between high α2AP levels and increased risk or poor outcome in cardiovascular diseases. Mechanistic studies in disease models indicate that α2AP stops the body's own fibrinolytic system from dissolving pathologic thrombi that cause venous thrombosis, pulmonary embolism, arterial thrombosis, and ischemic stroke. In addition, α2AP fosters the development of microvascular thrombosis and enhances matrix metalloproteinase-9 expression. Through these mechanisms and others, α2AP contributes to brain injury, hemorrhage and swelling in experimental ischemic stroke. Recent studies also show that α2AP is required for the development of stasis thrombosis by inhibiting the early activation of effective fibrinolysis. In this review, we will discuss the key role played by α2AP in controlling thrombosis and fibrinolysis and, we will consider its potential value as a therapeutic target in cardiovascular diseases and ischemic stroke.
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Affiliation(s)
- Satish Singh
- Department of Medicine, University of Arizona-College of Medicine, Phoenix, AZ, United States
| | - Sofiyan Saleem
- Department of Medicine, University of Arizona-College of Medicine, Phoenix, AZ, United States
| | - Guy L Reed
- Department of Medicine, University of Arizona-College of Medicine, Phoenix, AZ, United States
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4
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Singh S, Houng AK, Wang D, Reed GL. Physiologic variations in blood plasminogen levels affect outcomes after acute cerebral thromboembolism in mice: a pathophysiologic role for microvascular thrombosis. J Thromb Haemost 2016; 14:1822-32. [PMID: 27319402 PMCID: PMC5035596 DOI: 10.1111/jth.13390] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/13/2016] [Indexed: 12/14/2022]
Abstract
UNLABELLED Essentials Physiologic variations in blood plasminogen (Pg) levels may affect ischemic stroke outcomes. We tested Pg effects in a model with translational relevance to human thromboembolic stroke. A dose-response exists between Pg levels and brain injury, fibrinolysis, barrier breakdown. Higher Pg levels reduce microvascular thrombosis and improve outcomes in ischemic stroke. SUMMARY Background and Objectives Plasminogen appears to affect brain inflammation, cell movement, fibrinolysis, neuronal excitotoxicity, and cell death. However, brain tissue and circulating blood plasminogen may have different roles, and there is wide individual variation in blood plasminogen levels. The aim of this study was to determine the integrated effect of blood plasminogen levels on ischemic brain injury. Methods We examined thromboembolic stroke in mice with varying, experimentally determined, blood plasminogen levels. Ischemic brain injury, blood-brain barrier breakdown, matrix metalloproteinase-9 expression and microvascular thrombosis were determined. Results Within the range of normal variation, plasminogen levels were strongly associated with ischemic brain injury; higher blood plasminogen levels had dose-related, protective effects. Higher plasminogen levels were associated with increased dissolution of the middle cerebral artery thrombus. Higher plasminogen levels decreased blood-brain barrier breakdown, matrix metalloproteinase-9 expression and microvascular thrombosis in the ischemic brain. In plasminogen-deficient mice, selective restoration of blood plasminogen levels reversed the harmful effects of plasminogen deficiency on ischemic brain injury. Specific inhibition of thrombin also reversed the effect of plasminogen deficiency on ischemic injury by decreasing microvascular thrombosis, blood-brain barrier breakdown, and matrix metalloproteinase-9 expression. Conclusions Variation in blood plasminogen levels, within the range seen in normal individuals, had marked effects on experimental ischemic brain injury. Higher plasminogen levels protected against ischemic brain injury, and decreased blood-brain barrier breakdown, matrix metalloproteinase-9 expression, and microvascular thrombosis. The protective effects of blood plasminogen appear to be mediated largely through a decrease in microvascular thrombosis in the ischemic territory.
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Affiliation(s)
- S Singh
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - A K Houng
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - D Wang
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - G L Reed
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA.
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Reed GL, Houng AK, Singh S, Wang D. α2-Antiplasmin: New Insights and Opportunities for Ischemic Stroke. Semin Thromb Hemost 2016; 43:191-199. [PMID: 27472428 DOI: 10.1055/s-0036-1585077] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Thrombotic vascular occlusion is the leading cause of ischemic stroke. High blood levels of α2-antiplasmin (a2AP), an ultrafast, covalent inhibitor of plasmin, have been linked in humans to increased risk of ischemic stroke and failure of tissue plasminogen activator (tPA) therapy. Consistent with these observations, a2AP neutralizes the therapeutic benefit of tPA therapy in experimental stroke. In addition, a2AP has deleterious, dose-related effects on ischemic brain injury in the absence of therapy. Experimental therapeutic inactivation of a2AP markedly reduces microvascular thrombosis, ischemic brain injury, brain swelling, brain hemorrhage, and death after thromboembolic stroke. These data provide new insights into the critical importance of a2AP in the pathogenesis of ischemic brain injury and suggest that transiently inactivating a2AP may have therapeutic value in ischemic stroke.
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Affiliation(s)
- Guy L Reed
- Department of Medicine, University of Tennessee Health Sciences Center, Memphis, Tennessee
| | - Aiilyan K Houng
- Department of Medicine, University of Tennessee Health Sciences Center, Memphis, Tennessee
| | - Satish Singh
- Department of Medicine, University of Tennessee Health Sciences Center, Memphis, Tennessee
| | - Dong Wang
- Department of Medicine, University of Tennessee Health Sciences Center, Memphis, Tennessee
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Song SJ, Smiddy WE. Ocriplasmin for symptomatic vitreomacular adhesion: an evidence-based review of its potential. CORE EVIDENCE 2014; 9:51-9. [PMID: 24711777 PMCID: PMC3968080 DOI: 10.2147/ce.s39363] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Vitreomacular traction is a multicategory entity that may cause substantial visual loss due to the formation of a macular hole or traction-induced tissue distortion. The advent of optical coherent tomography (OCT) has demonstrated the anatomic features of persistent vitreomacular attachment (VMA) more definitively, including in many asymptomatic or minimally symptomatic patients. The indications for intervention are unclear, since it is not possible to predict which eyes might be likely to develop progressive visual loss. This has been especially important since for many years, the only treatment option involved surgical intervention (vitrectomy) to release the persistent VMA. Recently, a pharmacolytic agent, ocriplasmin, has become available after many years of development and investigation, and may offer a feasible alternative to surgery, or even a risk/benefit ratio sufficiently favorable to offer intervention at an earlier stage of VMA. Several studies, including a large, prospective clinical trial, have established the foundation of its rationale and efficacy, providing the basis of its approval. The role for ocriplasmin in clinical practice is in the process of being determined. This paper summarizes current knowledge and status of investigations regarding ocriplasmin-induced pharmacologic vitreolysis, and offers some evidence-based considerations for its use.
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Affiliation(s)
- Su Jeong Song
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA ; Department of Ophthalmology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - William E Smiddy
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
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Reversing the deleterious effects of α2-antiplasmin on tissue plasminogen activator therapy improves outcomes in experimental ischemic stroke. Exp Neurol 2014; 255:56-62. [PMID: 24556477 DOI: 10.1016/j.expneurol.2014.02.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 01/17/2014] [Accepted: 02/07/2014] [Indexed: 12/20/2022]
Abstract
High blood levels of α2-antiplasmin have been associated with failed tissue plasminogen activator (TPA) therapy for ischemic stroke. Yet, other data suggests that α2-antiplasmin may be protective in stroke, because it defends against bleeding and excitotoxicity. To address this paradox, we examined the effects of high α2-antiplasmin levels and α2-antiplasmin inactivation in mice treated with TPA 0.5-2.5h after middle cerebral artery (MCA) thromboembolism. Brain infarction, swelling, hemorrhage, blood brain barrier breakdown and neuronal apoptosis were measured by a blinded observer. Thrombus dissolution was determined by gamma counting. During TPA treatment, high α2-antiplasmin blood levels increased brain infarction (2.2-fold) and swelling (3.7-fold), but decreased MCA thrombus dissolution. Conversely, α2-antiplasmin inactivation during TPA treatment reduced brain infarction, hemorrhage and swelling, but increased MCA thrombus dissolution. Inactivation of α2-antiplasmin during TPA treatment reduced neuronal apoptosis and blood brain barrier breakdown. Inactivation of α2-antiplasmin also reduced short-term mortality. Taken together these data show that α2-antiplasmin opposes the effects of TPA therapy and contributes to enhanced brain injury after experimental thromboembolic stroke. Conversely, α2-antiplasmin inactivation during TPA treatment improves thrombus dissolution and reduces brain infarction, swelling and hemorrhage. Consistent with clinical observations, these data suggest that α2-antiplasmin exerts deleterious effects that reduce the efficacy and safety of TPA therapy for ischemic stroke.
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Polat SB, Ugurlu N, Yulek F, Simavli H, Ersoy R, Cakir B, Erel O. Evaluation of serum fibrinogen, plasminogen, α2-anti-plasmin, and plasminogen activator inhibitor levels (PAI) and their correlation with presence of retinopathy in patients with type 1 DM. J Diabetes Res 2014; 2014:317292. [PMID: 24818165 PMCID: PMC4003747 DOI: 10.1155/2014/317292] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 03/16/2014] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND. Diabetic retinopathy (DR) is the leading cause of blindness in the world. Retinopathy can still progress despite optimal metabolic control. The aim of the study was to determine whether different degrees of DR (proliferative or nonproliferative) were associated with abnormally modulated hemostatic parameters in patients with T1DM. METHOD. 52 T1DM patients and 40 healthy controls were enrolled in the study. Patients were subdivided into three categories. Group I was defined as those without retinopathy, group II with NPRP, and group III with PRP. We compared these subgroups with each other and the control group (Group IV) according to the serum fibrinogen, plasminogen, alpha2-anti-plasmin ( α2-anti-plasmin), and PAI. RESULTS. We detected that PAI-1, serum fibrinogen, and plasminogen levels were similar between the diabetic and control groups (P = 0.209, P = 0.224, and P = 0.244, resp.), whereas α2-anti-plasmin was higher in Groups I, II, and III compared to the control group (P < 0.01, P < 0.05, and P < 0.001, resp.). There was a positive correlation between serum α2-anti-plasmin and HbA1c levels (r = 0,268, P = 0.031). CONCLUSION. To our knowledge there is scarce data in the literature about α2-anti-plasmin levels in type 1 diabetes. A positive correlation between α2-anti-plasmin with HbA1c suggests that fibrinolytic markers may improve with disease regulation and better glycemic control.
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Affiliation(s)
- Sefika Burcak Polat
- Endocrinology and Metabolism Department, Ataturk Training and Research Hospital, Yildirim Beyazit University, 6800 Ankara, Turkey
- *Sefika Burcak Polat:
| | - Nagihan Ugurlu
- Ophthalmology Department, Ataturk Training and Research Hospital, Yildirim Beyazit University, Ankara, Turkey
| | - Fatma Yulek
- Ophthalmology Department, Ataturk Training and Research Hospital, Yildirim Beyazit University, Ankara, Turkey
| | - Huseyin Simavli
- Ophtalmology Department, Izzet Baysal Government Hospital, Bolu, Turkey
| | - Reyhan Ersoy
- Endocrinology and Metabolism Department, Ataturk Training and Research Hospital, Yildirim Beyazit University, 6800 Ankara, Turkey
| | - Bekir Cakir
- Endocrinology and Metabolism Department, Ataturk Training and Research Hospital, Yildirim Beyazit University, 6800 Ankara, Turkey
| | - Ozcan Erel
- Department of Biochemistry, Ataturk Training and Research Hospital, Yildirim Beyazit University, Ankara, Turkey
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Di Nardo MA, Annunziata ML, Ammirabile M, Di Minno MND, Ruocco AL, De Falco M, Di Lieto A. Pelvic adhesion and gonadotropin-releasing hormone analogue: effects of triptorelin acetate depot on coagulation and fibrinolytic activities. Reprod Sci 2012; 19:615-22. [PMID: 22344729 DOI: 10.1177/1933719111428517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The study investigated the impact of gonadotropin-releasing hormone analogue (GnRH-a) on coagulation and fibrinolytic activities and its effectiveness in the prevention of pelvic adhesion after myomectomy. Thirty-two infertile women underwent myomectomy followed by adhesion evaluation surgery with a second-look laparoscopy. Before myomectomy, 15 women were treated with triptorelin acetate for 3 months and 17 received no treatment. Plasminogen activator inhibitor (PAI), thrombin activatable fibrinolysis inhibitor (TAFI), protein C (PC), plasminogen, α2-antiplasmin were determined by enzyme-linked immunosorbent assays and the activity of coagulation factors V and VIII by coagulometric methods. Patients treated with GnRH-a showed significant decrease in PAI, TAFI, factors V, and VIII (P < .05) and increased PC (P < .05), but no significant change in plasminogen and α2-antiplasmin levels compared with control group. The incidence, extent, and severity of adhesions were significantly lower in GnRH-a-treated patients compared with control group (P < .05), suggesting a possible critical role of the GnRH-a therapy in preventing postoperative adhesion development.
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Affiliation(s)
- Maria Antonietta Di Nardo
- Department of Obstetrical-Gynecological and Urological Science and Reproductive Medicine, Federico II University, Naples, Italy.
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Abstract
The coagulation and fibrinolytic pathways regulate hemostasis and thrombosis, and an imbalance in these pathways may result in pathologic hemophilia or thrombosis. The plasminogen system is the primary proteolytic pathway for fibrinolysis, but also has important proteolytic functions in cell migration, extracellular matrix degradation, metalloproteinase activation, and hormone processing. Several studies have demonstrated plasmin cleavage and inactivation of several coagulation factors, suggesting plasmin may be not only be the primary fibrinolytic enzyme, but may have anticoagulant properties as well. The objective of this review is to examine both in vitro and in vivo evidence for plasmin inactivation of coagulation, and to consider whether plasmin may act as a physiological regulator of coagulation. While several studies have demonstrated strong evidence for plasmin cleavage and inactivation of coagulation factors FV, FVIII, FIX, and FX in vitro, in vivo evidence is lacking for a physiologic role for plasmin as an anticoagulant. However, inactivation of coagulation factors by plasmin may be useful as a localized anticoagulant therapy or as a combined thrombolytic and anticoagulant therapy.
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Affiliation(s)
- Jane Hoover-Plow
- Joseph J Jacobs Center for Thrombosis and Vascular Biology, Department of Cardiovascular Medicine, Lerner Research Institute Cleveland Clinic, Cleveland, Ohio 44195, USA.
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Sazonova IY, McNamee RA, Houng AK, King SM, Hedstrom L, Reed GL. Reprogrammed streptokinases develop fibrin-targeting and dissolve blood clots with more potency than tissue plasminogen activator. J Thromb Haemost 2009; 7:1321-8. [PMID: 19566545 PMCID: PMC3911889 DOI: 10.1111/j.1538-7836.2009.03491.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Given the worldwide epidemic of cardiovascular diseases, a more effective means of dissolving thrombi that cause heart attacks, could markedly reduce death, disability and healthcare costs. Plasminogen activators (PAs) such as streptokinase (SK) and tissue plasminogen activator (TPA) are currently used to dissolve fibrin thrombi. SK is cheaper and more widely available, but it appears less effective because it lacks TPA's fibrin-targeted properties that focus plasminogen activation on the fibrin surface. OBJECTIVE We examined whether re-programming SK's mechanism of action would create PAs with greater fibrin-targeting and potency than TPA. METHODS AND RESULTS When fibrinogen consumption was measured in human plasma, reprogrammed molecules SKDelta1 and SKDelta59 were 5-fold and > 119-fold more fibrin-dependent than SK (P < 0.0001), and 2-fold and > 50-fold more fibrin-dependent than TPA (P < 0.001). The marked fibrin-targeting of SKDelta59 was due to the fact that: (i) it did not generate plasmin in plasma, (ii) it was rapidly inhibited by alpha2-antiplasmin, and (iii) it only processed fibrin-bound plasminogen. To assess the fibrin-targeting and therapeutic potential of these PAs in vivo, a novel 'humanized' fibrinolysis model was created by reconstituting plasminogen-deficient mice with human plasminogen. When compared with TPA, SKDelta1 and SKDelta59 were 4-fold (P < 0.0001) and 2-fold (P < 0.003) more potent at dissolving blood clots in vivo, respectively, on a mass-dose basis and 2-3 logs more potent than TPA (P < 0.0001) when doses were calibrated by standard activity assays. CONCLUSION These experiments suggest that reprogramming SK's mechanism of action markedly enhances fibrin-targeting and creates, in comparison with TPA, activators with greater fibrinolytic potency.
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Affiliation(s)
- I Y Sazonova
- Cardiovascular Research Medical College of Georgia, Augusta, GA, USA
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