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Che K, Pobbati AV, Seavey CN, Fedorov Y, Komar AA, Burtscher A, Ma S, Rubin BP. Aurintricarboxylic acid is a canonical disruptor of the TAZ-TEAD transcriptional complex. PLoS One 2022; 17:e0266143. [PMID: 35417479 PMCID: PMC9007350 DOI: 10.1371/journal.pone.0266143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/14/2022] [Indexed: 01/07/2023] Open
Abstract
Disrupting the formation of the oncogenic YAP/TAZ-TEAD transcriptional complex holds substantial therapeutic potential. However, the three protein interaction interfaces of this complex cannot be easily disrupted using small molecules. Here, we report that the pharmacologically active small molecule aurintricarboxylic acid (ATA) acts as a disruptor of the TAZ-TEAD complex. ATA was identified in a high-throughput screen using a TAZ-TEAD AlphaLISA assay that was tailored to identify disruptors of this transcriptional complex. We further used fluorescence polarization assays both to confirm disruption of the TAZ-TEAD complex and to demonstrate that ATA binds to interface 3. We have previously shown that cell-based models that express the oncogenic TAZ-CAMTA1 (TC) fusion protein display enhanced TEAD transcriptional activity because TC functions as an activated form of TAZ. Utilizing cell-based studies and our TC model system, we performed TC/TEAD reporter, RNA-Seq, and qPCR assays and found that ATA inhibits TC/TEAD transcriptional activity. Further, disruption of TC/TEAD and TAZ/TEAD interaction by ATA abrogated anchorage-independent growth, the phenotype most closely linked to dysregulated TAZ/TEAD activity. Therefore, this study demonstrates that ATA is a novel small molecule that has the ability to disrupt the undruggable TAZ-TEAD interface.
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Affiliation(s)
- Kepeng Che
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Ajaybabu V. Pobbati
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Caleb N. Seavey
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- Department of General Surgery, Digestive Disease and Surgery Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Yuriy Fedorov
- Small Molecule Drug Development Core, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Anton A. Komar
- Department of Biological, Geological and Environmental Sciences, Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland, Ohio, United States of America
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Ashley Burtscher
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Shuang Ma
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Brian P. Rubin
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
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Bonnefoy A, Vermylen J, Hoylaerts MF. Inhibition of von Willebrand factor-GPIb/IX/V interactions as a strategy to prevent arterial thrombosis. Expert Rev Cardiovasc Ther 2014; 1:257-69. [PMID: 15030285 DOI: 10.1586/14779072.1.2.257] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although drugs exist for the primary and secondary prevention of thrombosis, more potent antiplatelet drugs with sufficiently wide therapeutic windows to avoid bleeding complications are needed. Both academic and pharmaceutical laboratories are working to develop such drugs. This chapter reviews the potential of inhibiting interactions between von Willebrand factor (vWF) and the second most abundant receptor on the platelet, the glycoprotein (GP) Ib/IX/V complex, interactions that are essential for the activation of circulating platelets, contacting a vessel wall injury. Although still at the level of preclinical testing, this area is expected to progress quickly during the next few years, also in view of the three-dimensional structural information that has recently become available and that allows a molecular understanding of vWF binding to the GPIbalpha chain of the GPIb complex.
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Affiliation(s)
- Arnaud Bonnefoy
- Center for Molecular and Vascular Biology, University of Leuven, Belgium
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3
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Kiki İ, Köse N, Gündoğdu M, Kaya H, Çetinkaya R. RELATIONSHIP BETWEEN VON WILLEBRAND FACTOR ACTIVITY AND THERAPEUTIC SUCCESS OF THROMBOLYTIC THERAPY IN PATIENTS WITH MYOCARDIAL INFARCTION. ELECTRONIC JOURNAL OF GENERAL MEDICINE 2007. [DOI: 10.29333/ejgm/82456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Thromboembolic diseases remain the main cause of death in Western societies despite current antithrombotic treatments. Recent advances in the molecular bases of haemostasis have highlighted new targets for novel antiplatelet or anticoagulant agents. Considering antiplatelet agents, selective antagonists of specific receptors (von Willebrand factor, collagen or thrombin receptors) are effective in thrombosis models and direct ADP receptor antagonists and nitric-oxide-releasing aspirin are in Phase I-II clinical trials. Concerning anticoagulants, inhibitors of tissue-factor-induced clotting activation, selective inhibitors of thrombin and factor Xa, and components of the anticoagulant protein C system (recombinant activated human protein C or human soluble thrombomodulin) have been studied. Some of these agents have had promising results in Phase III studies. Several achievements are anticipated from the development of new antithrombotics, including a further reduction of cardiovascular mortality and unwanted bleeding, and easier patient management.
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Affiliation(s)
- Paolo Gresele
- Division of Internal and Cardiovascular Medicine, Dept of Internal Medicine, University of Perugia, Via E. Dal Pozzo, I-06126, Perugia, Italy.
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5
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Rozalski M, Boncler M, Golanski J, Watala C. Effects of fibrinogen receptor antagonist GR144053F and aurintricarboxylic acid on platelet activation and degranulation. Biochem Pharmacol 2001; 62:1399-408. [PMID: 11709200 DOI: 10.1016/s0006-2952(01)00777-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Activated blood platelets play crucial role in restenosis due to their fundamental significance in thrombus formation. Therefore, platelets are attractive targets for the inhibition with a variety of antagonists. In this study, we present direct evidence that GR144053F [non-peptide antagonist of glycoprotein IIb-IIIa complex (GPIIb-IIIa)] inhibits activation and degranulation of human platelets, and opposes the action of aurintricarboxylic acid (ATA), the antagonist of von Willebrand factor, which augments platelet secretion. The effects of both drugs on platelet function were monitored by using various instrumental methods. Platelet-rich plasma and whole-blood aggregation was measured by using ADP and collagen as agonists. Platelet degranulation was assessed based on the expression of surface membrane activation markers: P-selectin, glycoprotein Ib, and activated GPIIb-IIIa complex. Measurements of closure time with platelet function analyzer PFA-100 enabled us to reason on primary hemostatic capacity and reflected both aggregability and adhesiveness. GR144053F markedly reduced primary hemostatic platelet response (IC(50) = 114.0 +/- 9.6 nM) under conditions that closely mimicked natural blood flow in circulation, and inhibited aggregation in platelet-rich plasma (IC(50) = 17.7 +/- 7.0 nM). It was equally potent inhibitor of platelet activation, degranulation, fibrinogen binding, platelet consumption, and aggregate formation. Also, ATA was efficient in inhibition of platelet aggregation and adhesion (by up to 50% at 100 microM), but the combined action of both drugs on primary haemostatic capacity was not additive. GR144053F suppressed the activating effects of ATA on platelet degranulation and secretion. Overall, our data indicate that GR144053F is not only the efficient blocker of fibrinogen binding to GPIIb-IIIa, but also hampers platelet degranulation and may attenuate the activating effects of ATA.
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Affiliation(s)
- M Rozalski
- Laboratory of Haemostasis and Haemostatic Disorders, Medical University of Lodz, Narutowicza 96, 90-141, Lodz, Poland
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6
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Abstract
OBJECTIVE To determine whether platelets obtained from cats expressed glycoprotein Ib (GPIb). SAMPLE POPULATION Platelets obtained from 11 specific-pathogen-free cats. PROCEDURE Platelets were analyzed by use of immunofluorescence microscopy, flow cytometry, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, western immunoblot analysis, and immunoprecipitation. RESULTS Immunofluorescence microscopy and flow cytometry revealed the protein on the surface of feline platelets. Biochemical studies (western immunoblot analysis and immunoprecipitation) revealed a 140-kd membrane glycoprotein. Additional biochemical studies revealed that feline GPIb was sensitive to proteolysis, because platelet cytoskeletons prepared with low concentrations of a calpain inhibitor (ie, leupeptin; 100 microg/ml) had substantial proteolysis, and there was an association of protein fragments with the actin cytoskeleton. CONCLUSIONS AND CLINICAL RELEVANCE Analysis of these results indicate that feline platelets express a 140-kd membrane protein that is recognized by monoclonal antibodies developed against GPIb. Application of standardized ELISA to quantitate glycocalicin, the water-soluble fragment of GPIb, may provide important information on the production of microvesicles, increased platelet turnover, and abnormal proteolysis.
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Affiliation(s)
- F Tablin
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, USA
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7
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Yamamoto J, Kawano M, Hashimoto M, Sasaki Y, Yamashita T, Taka T, Watanabe S, Giddings JC. Adjuvant effect of antibodies against von Willebrand Factor, fibrinogen, and fibronectin on staphylokinase-induced thrombolysis as measured using mural thrombi formed in rat mesenteric venules. Thromb Res 2000; 97:327-33. [PMID: 10709908 DOI: 10.1016/s0049-3848(99)00184-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The change in thrombus mass during thrombolytic therapy is thought to be the difference between its growth and its degradation induced by thrombolytic agents. Platelets play a pivotal role in arterial thrombosis and bind to each other and to exposed subendothelial matrices via adhesive proteins such as von Willebrand Factor, fibrinogen, and fibronectin. The aim of the present study was to assess whether administration of antibodies against these adhesive proteins, in conjunction with plasminogen activator, could enhance the degradation of platelet-rich thrombus. Mural platelet-rich thrombi were formed in rat mesenteric venules using He-Ne laser irradiation. Recombinant staphylokinase was infused continuously and polyclonal antibodies against adhesive proteins were given by bolus injection. The thrombolytic process was analysed using computer-enhanced image analysis software. Administration of each of the antibodies enhanced staphylokinase-induced thrombolysis.
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Affiliation(s)
- J Yamamoto
- Laboratory of Physiology, Faculty of Nutrition, Kobe Gakuin University, Japan.
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Unique Antiplatelet Effects of a Novel S-Nitrosoderivative of a Recombinant Fragment of von Willebrand Factor, AR545C: In Vitro and Ex Vivo Inhibition of Platelet Function. Blood 1999. [DOI: 10.1182/blood.v94.5.1693.417k32_1693_1700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The recombinant fragment of von Willebrand factor (vWF) spanning Ala444 to Asp730 and containing an Arg545Cys mutation (denoted AR545C) has antithrombotic properties that are principally a consequence of its ability to inhibit platelet adhesion to subendothelial matrix. Endothelial-derived nitric oxide (NO) can also inhibit platelet function, both as a consequence of inhibiting adhesion as well as activation and aggregation. Nitric oxide can react with thiol functional groups in the presence of oxygen to form S-nitrosothiols, which are naturally occurring NO derivatives that prolong the biological actions of NO. Because AR545C has a single free cysteine (Cys545), we attempted to synthesize the S-nitroso-derivative of AR545C and to characterize its antiplatelet effects. We successfully synthesized S-nitroso-AR545C and found that it contained 0.96 mol S-NO per mole peptide. S-nitroso-AR545C was approximately 5-fold more potent at inhibiting platelet agglutination than was the unmodified peptide (IC50 = 0.02 ± 0.006 μmol/L v 0.1 ± 0.03 μmol/L, P = .001). In addition and by contrast, S-nitroso-AR545C was a powerful inhibitor of adenosine diphosphate–induced platelet aggregation (IC50 = 0.018 ± 0.002 μmol/L), while AR545C had no effect on aggregation. These effects were confirmed in studies of adhesion to and aggregation on extracellular matrix under conditions of shear stress in a cone-plate viscometer, where 1.5 μmol/L S-nitroso-AR545C inhibited platelet adhesion by 83% and essentially completely inhibited aggregate formation, while the same concentration of AR545C inhibited platelet adhesion by 74% and had significantly lesser effect on aggregate formation on matrix (P ≤ .004 for each parameter by ANOVA). In an ex vivo rabbit model, we also found that S-nitroso-AR545C had a more marked and more durable inhibitory effect on botrocetin-induced platelet aggregation than did AR545C, and these differences were also reflected in the extent and duration of effect on the prolongation of the bleeding time in these animals. These data show that S-nitroso-AR545C has significant and unique antiplatelet effects, inhibiting both adhesion and aggregation, by blocking platelet GPIb receptor through the AR545C moiety and elevating platelet cyclic 3′,5′-guanosine monophosphate through the -SNO moiety. These observations suggest that this NO-modified fragment of vWF may have potential therapeutic benefits as a unique antithrombotic agent.
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9
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Unique Antiplatelet Effects of a Novel S-Nitrosoderivative of a Recombinant Fragment of von Willebrand Factor, AR545C: In Vitro and Ex Vivo Inhibition of Platelet Function. Blood 1999. [DOI: 10.1182/blood.v94.5.1693] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThe recombinant fragment of von Willebrand factor (vWF) spanning Ala444 to Asp730 and containing an Arg545Cys mutation (denoted AR545C) has antithrombotic properties that are principally a consequence of its ability to inhibit platelet adhesion to subendothelial matrix. Endothelial-derived nitric oxide (NO) can also inhibit platelet function, both as a consequence of inhibiting adhesion as well as activation and aggregation. Nitric oxide can react with thiol functional groups in the presence of oxygen to form S-nitrosothiols, which are naturally occurring NO derivatives that prolong the biological actions of NO. Because AR545C has a single free cysteine (Cys545), we attempted to synthesize the S-nitroso-derivative of AR545C and to characterize its antiplatelet effects. We successfully synthesized S-nitroso-AR545C and found that it contained 0.96 mol S-NO per mole peptide. S-nitroso-AR545C was approximately 5-fold more potent at inhibiting platelet agglutination than was the unmodified peptide (IC50 = 0.02 ± 0.006 μmol/L v 0.1 ± 0.03 μmol/L, P = .001). In addition and by contrast, S-nitroso-AR545C was a powerful inhibitor of adenosine diphosphate–induced platelet aggregation (IC50 = 0.018 ± 0.002 μmol/L), while AR545C had no effect on aggregation. These effects were confirmed in studies of adhesion to and aggregation on extracellular matrix under conditions of shear stress in a cone-plate viscometer, where 1.5 μmol/L S-nitroso-AR545C inhibited platelet adhesion by 83% and essentially completely inhibited aggregate formation, while the same concentration of AR545C inhibited platelet adhesion by 74% and had significantly lesser effect on aggregate formation on matrix (P ≤ .004 for each parameter by ANOVA). In an ex vivo rabbit model, we also found that S-nitroso-AR545C had a more marked and more durable inhibitory effect on botrocetin-induced platelet aggregation than did AR545C, and these differences were also reflected in the extent and duration of effect on the prolongation of the bleeding time in these animals. These data show that S-nitroso-AR545C has significant and unique antiplatelet effects, inhibiting both adhesion and aggregation, by blocking platelet GPIb receptor through the AR545C moiety and elevating platelet cyclic 3′,5′-guanosine monophosphate through the -SNO moiety. These observations suggest that this NO-modified fragment of vWF may have potential therapeutic benefits as a unique antithrombotic agent.
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10
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Affiliation(s)
- J I Weitz
- Hamilton Civic Hospitals Research Centre, ON, Canada
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11
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Abstract
AbstractPlatelet membrane glycoprotein Ib (GPIb) is a major receptor for von Willebrand factor and thrombin, which plays a key role in the initial development of thrombi. Two polymorphisms (HPA-2 and VNTR) that affect phenotype have been described in GPIb. The relevance of these polymorphisms to thrombotic disease was investigated by genotypic identification in three case-control studies: 104 case patients with acute cerebrovascular disease (CVD), 101 case patients with acute coronary heart disease (CHD), 95 patients with deep venous thrombosis (DVT), and one control age-, sex-, and race-matched for each case patient. Results show that the C/B genotype of the VNTR and the HPA-2b polymorphisms of GPIb are strongly associated with increased risk of coronary heart disease and cerebral vascular disease but not with deep vein thrombosis. These two polymorphisms of GPIb may represent newly identified risk factors for arterial thrombotic disease, but not for venous thrombosis.© 1998 by The American Society of Hematology.
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12
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Abstract
Platelet membrane glycoprotein Ib (GPIb) is a major receptor for von Willebrand factor and thrombin, which plays a key role in the initial development of thrombi. Two polymorphisms (HPA-2 and VNTR) that affect phenotype have been described in GPIb. The relevance of these polymorphisms to thrombotic disease was investigated by genotypic identification in three case-control studies: 104 case patients with acute cerebrovascular disease (CVD), 101 case patients with acute coronary heart disease (CHD), 95 patients with deep venous thrombosis (DVT), and one control age-, sex-, and race-matched for each case patient. Results show that the C/B genotype of the VNTR and the HPA-2b polymorphisms of GPIb are strongly associated with increased risk of coronary heart disease and cerebral vascular disease but not with deep vein thrombosis. These two polymorphisms of GPIb may represent newly identified risk factors for arterial thrombotic disease, but not for venous thrombosis.© 1998 by The American Society of Hematology.
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Antithrombotic Effect of Crotalin, a Platelet Membrane Glycoprotein Ib Antagonist From Venom of Crotalus atrox. Blood 1998. [DOI: 10.1182/blood.v91.5.1582] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractA potent platelet glycoprotein Ib (GPIb) antagonist, crotalin, with a molecular weight of 30 kD was purified from the snake venom ofCrotalus atrox. Crotalin specifically and dose dependently inhibited aggregation of human washed platelets induced by ristocetin with IC50 of 2.4 μg/mL (83 nmol/L). It was also active in inhibiting ristocetin-induced platelet aggregation of platelet-rich plasma (IC50, 6.3 μg/mL). 125I-crotalin bound to human platelets in a saturable and dose-dependent manner with a kd value of 3.2 ± 0.1 × 10−7 mol/L, and its binding site was estimated to be 58,632 ± 3,152 per platelet. Its binding was specifically inhibited by a monoclonal antibody, AP1 raised against platelet GPIb. Crotalin significantly prolonged the latent period in triggering platelet aggregation caused by low concentration of thrombin (0.03 U/mL), and inhibited thromboxane B2formation of platelets stimulated either by ristocetin plus von Willebrand factor (vWF), or by thrombin (0.03 U/mL). When crotalin was intravenously (IV) administered to mice at 100 to 300 μg/kg, a dose-dependent prolongation on tail bleeding time was observed. The duration of crotalin in prolonging tail bleeding time lasted for 4 hours as crotalin was given at 300 μg/kg. In addition, its in vivo antithrombotic activity was evidenced by prolonging the latent period in inducing platelet-rich thrombus formation by irradiating the mesenteric venules of the fluorescein sodium-treated mice. When administered IV at 100 to 300 μg/kg, crotalin dose dependently prolonged the time lapse in inducing platelet-rich thrombus formation. In conclusion, crotalin specifically inhibited vWF-induced platelet agglutination in the presence of ristocetin because crotalin selectively bound to platelet surface receptor-glycoprotein Ib, resulting in the blockade of the interaction of vWF with platelet membrane GPIb. In addition, crotalin is a potent antithrombotic agent because it pronouncedly blocked platelet plug formation in vivo.
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Antithrombotic Effect of Crotalin, a Platelet Membrane Glycoprotein Ib Antagonist From Venom of Crotalus atrox. Blood 1998. [DOI: 10.1182/blood.v91.5.1582.1582_1582_1589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A potent platelet glycoprotein Ib (GPIb) antagonist, crotalin, with a molecular weight of 30 kD was purified from the snake venom ofCrotalus atrox. Crotalin specifically and dose dependently inhibited aggregation of human washed platelets induced by ristocetin with IC50 of 2.4 μg/mL (83 nmol/L). It was also active in inhibiting ristocetin-induced platelet aggregation of platelet-rich plasma (IC50, 6.3 μg/mL). 125I-crotalin bound to human platelets in a saturable and dose-dependent manner with a kd value of 3.2 ± 0.1 × 10−7 mol/L, and its binding site was estimated to be 58,632 ± 3,152 per platelet. Its binding was specifically inhibited by a monoclonal antibody, AP1 raised against platelet GPIb. Crotalin significantly prolonged the latent period in triggering platelet aggregation caused by low concentration of thrombin (0.03 U/mL), and inhibited thromboxane B2formation of platelets stimulated either by ristocetin plus von Willebrand factor (vWF), or by thrombin (0.03 U/mL). When crotalin was intravenously (IV) administered to mice at 100 to 300 μg/kg, a dose-dependent prolongation on tail bleeding time was observed. The duration of crotalin in prolonging tail bleeding time lasted for 4 hours as crotalin was given at 300 μg/kg. In addition, its in vivo antithrombotic activity was evidenced by prolonging the latent period in inducing platelet-rich thrombus formation by irradiating the mesenteric venules of the fluorescein sodium-treated mice. When administered IV at 100 to 300 μg/kg, crotalin dose dependently prolonged the time lapse in inducing platelet-rich thrombus formation. In conclusion, crotalin specifically inhibited vWF-induced platelet agglutination in the presence of ristocetin because crotalin selectively bound to platelet surface receptor-glycoprotein Ib, resulting in the blockade of the interaction of vWF with platelet membrane GPIb. In addition, crotalin is a potent antithrombotic agent because it pronouncedly blocked platelet plug formation in vivo.
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Kawano M, Watanabe S, Sasaki Y, Giddings JC, Yamamoto J. Adjuvant effect of argatroban on staphylokinase induced thrombolysis of platelet rich thrombi in rat mesenteric venules in vivo. Thromb Res 1997; 86:115-26. [PMID: 9175233 DOI: 10.1016/s0049-3848(97)00055-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Effective, therapeutic thrombolysis should not only promote dissolution of fibrin but should also regulate continued thrombin-induced fibrin formation and the accumulation of platelets on the thrombotic lesion. The aim of the present study was to assess the use of a synthetic, low molecular weight thrombin inhibitor, argatroban in association with a well defined thrombolytic agent in a reproducible animal model of thrombolysis in vivo. Thrombi were formed in rat mesenteric venules with a helium neon (He-Ne) laser in the presence of Evans blue and were stabilised for 10 minutes. Thrombi formed in this manner were shown by transmission electron microscopy to be composed mainly of platelets. Thrombolysis was induced with recombinant staphylokinase in the presence and absence of argatroban and the process was monitored using computerised image analysis. Co-infusion of argatroban at a dose of 2.0 mg/kg/h with staphylokinase significantly enhanced the rate of thrombolysis. The results suggested that administration of the thrombin inhibitor together with the fibrinolytic agent moderated platelet-dependent mechanisms and led to a more rapid restoration of blood vessel patency.
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Affiliation(s)
- M Kawano
- Laboratory of Physiology, Faculty of Nutrition, Kobe Gakuin University, Japan
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