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Vacik Díaz R, Munsch G, Iglesias MJ, Pallares Robles A, Ibrahim-Kosta M, Nourse J, Khan E, Castoldi E, Saut N, Boland A, Germain M, Deleuze JF, Odeberg J, Morange PE, Danckwardt S, Tregouët DA, Goumidi L. Plasma levels of complement components C5 and C9 are associated with thrombin generation. J Thromb Haemost 2024; 22:2531-2542. [PMID: 38838952 DOI: 10.1016/j.jtha.2024.04.026] [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: 09/11/2023] [Revised: 03/30/2024] [Accepted: 04/24/2024] [Indexed: 06/07/2024]
Abstract
BACKGROUND The thrombin generation assay (TGA) evaluates the potential of plasma to generate thrombin over time, providing a global picture of an individual's hemostatic balance. OBJECTIVES This study aimed to identify novel biological determinants of thrombin generation using a multiomics approach. METHODS Associations between TGA parameters and plasma levels of 377 antibodies targeting 236 candidate proteins for cardiovascular risk were tested using multiple linear regression analysis in 770 individuals with venous thrombosis from the Marseille Thrombosis Association (MARTHA) study. Proteins associated with at least 3 TGA parameters were selected for validation in an independent population of 536 healthy individuals (Etablissement Français du Sang Alpes-Méditerranée [EFS-AM]). Proteins with strongest associations in both groups underwent additional genetic analyses and in vitro experiments. RESULTS Eighteen proteins were associated (P < 1.33 × 10⁻4) with at least 3 TGA parameters in MARTHA, among which 13 demonstrated a similar pattern of associations in EFS-AM. Complement proteins C5 and C9 had the strongest associations in both groups. Ex vivo supplementation of platelet-poor plasma with purified C9 protein had a significant dose-dependent effect on TGA parameters. No effect was observed with purified C5. Several single nucleotide polymorphisms associated with C5 and C9 plasma levels were identified, with the strongest association for the C5 missense variant rs17611, which was associated with a decrease in C5 levels, endogenous thrombin potential, and peak in MARTHA. No association of this variant with TGA parameters was observed in EFS-AM. CONCLUSION This study identified complement proteins C5 and C9 as potential determinants of thrombin generation. Further studies are warranted to establish causality and elucidate the underlying mechanisms.
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Affiliation(s)
- Rocío Vacik Díaz
- Cardiovascular and Nutrition Research Center Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, Institut national de la santé et de la recherche médicale 1263, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement 1260, Marseille, France; Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg, Mainz, Germany. https://twitter.com/RocioVacik
| | - Gaëlle Munsch
- Institut national de la santé et de la recherche médicale Unité Mixte de Recherche_S 1219, Bordeaux Population Health Center, University of Bordeaux, Bordeaux, France
| | - Maria Jesus Iglesias
- Science for Life Laboratory, Kungliga Tekniska högskolan-Royal Institute of Technology, Stockholm, Sweden
| | - Alejandro Pallares Robles
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg, Mainz, Germany
| | - Manal Ibrahim-Kosta
- Cardiovascular and Nutrition Research Center Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, Institut national de la santé et de la recherche médicale 1263, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement 1260, Marseille, France; Department of Hematology, Centre Hospitalier Universitaire Timone, Marseille, France
| | - Jamie Nourse
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg, Mainz, Germany
| | - Essak Khan
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg, Mainz, Germany
| | - Elisabetta Castoldi
- Department of Biochemistry, Cell Biochemistry of Thrombosis and Haemostasis, Maastricht University, Maastricht, the Netherlands
| | - Noémie Saut
- Department of Hematology, Centre Hospitalier Universitaire Timone, Marseille, France
| | - Anne Boland
- Commissariat à l'énergie atomique et aux énergies alternatives, Centre National de Recherche en Génomique Humaine, Université Paris-Saclay, Evry, France
| | - Marine Germain
- Institut national de la santé et de la recherche médicale Unité Mixte de Recherche_S 1219, Bordeaux Population Health Center, University of Bordeaux, Bordeaux, France
| | - Jean-François Deleuze
- Commissariat à l'énergie atomique et aux énergies alternatives, Centre National de Recherche en Génomique Humaine, Université Paris-Saclay, Evry, France
| | - Jacob Odeberg
- Science for Life Laboratory, Kungliga Tekniska högskolan-Royal Institute of Technology, Stockholm, Sweden
| | - Pierre-Emmanuel Morange
- Cardiovascular and Nutrition Research Center Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, Institut national de la santé et de la recherche médicale 1263, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement 1260, Marseille, France; Department of Hematology, Centre Hospitalier Universitaire Timone, Marseille, France
| | - Sven Danckwardt
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg, Mainz, Germany
| | - David-Alexandre Tregouët
- Institut national de la santé et de la recherche médicale Unité Mixte de Recherche_S 1219, Bordeaux Population Health Center, University of Bordeaux, Bordeaux, France
| | - Louisa Goumidi
- Cardiovascular and Nutrition Research Center Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, Institut national de la santé et de la recherche médicale 1263, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement 1260, Marseille, France.
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Meijers JCM, van der Harst J, Marx PF, Sahbaie P, Clark DJ, Morser J. Brain Expression of CPB2 and Effects of Cpb2 Deficiency in Mouse Models of Behavior. Thromb Haemost 2024; 124:4-19. [PMID: 37532120 DOI: 10.1055/s-0043-1771304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2023]
Abstract
BACKGROUND Procarboxypeptidase B2 (proCPB2 or TAFI) is a zymogen that after activation cleaves C-terminal basic residues from peptides or proteins with many identified targets. A splice variant of CPB2 has been found in the brain lacking essential residues for its carboxypeptidase function. The aim was to determine CPB2 expression in the brain and effects of CPB2 deficiency (Cpb2 -/-) on behavior. MATERIALS AND METHODS Behavioral effects were tested by comparing Cpb2 -/- mice in short-term (open field and elevated zero maze tests) and long-term (Phenotyper) observations with wild-type (WT) controls. RESULTS Long-term observation compared day 1 (acclimatizing to novel environment) to day 4 (fully acclimatized) with the inactive (day) and active (night) periods analyzed separately. Brain expression of CPB2 mRNA and protein was interrogated in publicly available databases. Long-term observation demonstrated differences between WT and Cpb2 -/- mice in several parameters. For example, Cpb2 -/- mice moved more frequently on both days 1 and 4, especially in the normally inactive periods. Cpb2 -/- mice spent more time on the shelter and less time in it. Differences were more pronounced on day 4 after the mice had fully acclimatized. In short-term observations, no differences were observed between Cpb2 -/- mice and WT mice. Brain expression of CBP2 was not detectable in the human protein atlas. Databases of single-cell RNAseq did not show expression of CPB2 mRNA in either human or mouse brain. CONCLUSION Continuous observation of home-cage behavior suggests that Cpb2 -/- mice are more active than WT mice, show different day-night activity levels, and might have a different way of processing information.
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Affiliation(s)
- Joost C M Meijers
- Department of Experimental Vascular Medicine, Amsterdam UMC, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Pulmonary Hypertension and Thrombosis, Amsterdam, The Netherlands
- Department of Molecular Hematology, Sanquin Research, Amsterdam, The Netherlands
| | | | - Pauline F Marx
- Department of Experimental Vascular Medicine, Amsterdam UMC, Amsterdam, The Netherlands
| | - Peyman Sahbaie
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, California, United States
- Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, Palo Alto, California, United States
| | - David J Clark
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, California, United States
- Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, Palo Alto, California, United States
| | - John Morser
- Division of Hematology, Stanford University School of Medicine, Stanford, California, United States
- Palo Alto Institute of Research and Education, Veterans Affairs Palo Alto Health Care System, Palo Alto, California, United States
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Moore HB, Moore EE, Huebner BR, Dzieciatkowska M, Stettler GR, Nunns GR, Lawson PJ, Ghasabyan A, Chandler J, Banerjee A, Silliman C, Sauaia A, Hansen KC. Fibrinolysis shutdown is associated with a fivefold increase in mortality in trauma patients lacking hypersensitivity to tissue plasminogen activator. J Trauma Acute Care Surg 2017; 83:1014-1022. [PMID: 29190254 PMCID: PMC5726780 DOI: 10.1097/ta.0000000000001718] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Fibrinolysis shutdown (SD) is an independent risk factor for increased mortality in trauma. High levels of plasminogen activator inhibitor-1 (PAI-1) directly binding tissue plasminogen activator (t-PA) is a proposed mechanism for SD; however, patients with low PAI-1 levels present to the hospital with a rapid TEG (r-TEG) LY30 suggestive SD. We therefore hypothesized that two distinct phenotypes of SD exist, one, which is driven by t-PA inhibition, whereas another is due to an inadequate t-PA release in response to injury. METHODS Trauma activations from our Level I center between 2014 and 2016 with blood collected within an hour of injury were analyzed with r-TEG and a modified TEG assay to quantify fibrinolysis sensitivity using exogenous t-PA (t-TEG). Using the existing r-TEG thresholds for SD (<0.9%), physiologic (LY30 0.9-2.9%), and hyperfibrinolysis (LY30 > 2.9%) patients were stratified into phenotypes. A t-TEG LY30 greater than 95th percentile of healthy volunteers (n = 140) was classified as t-PA hypersensitive and used to subdivide phenotypes. A nested cohort had t-PA and PAI-1 activity levels measured in addition to proteomic analysis of additional fibrinolytic regulators. RESULTS This study included 398 patients (median New Injury Severity Score, 18), t-PA-Sen was present in 27% of patients. Shutdown had the highest mortality rate (20%) followed by hyperfibinolysis (16%) and physiologic (9% p = 0.020). In the non-t-PA hypersensitive cohort, SD had a fivefold increase in mortality (15%) compared with non-SD patients (3%; p = 0.003) which remained significant after adjusting for Injury Severity Score and age (p = 0.033). Overall t-PA activity (p = 0.002), PAI-1 (p < 0.001), and t-PA/PAI-1 complex levels (p = 0.006) differed between the six phenotypes, and 54% of fibrinolytic regulator proteins analyzed (n = 19) were significantly different. CONCLUSION In conclusion, acute fibrinolysis SD is not caused by a single etiology, and is clearly associated with PAI-1 activity. The differential phenotypes require an ongoing investigation to identify the optimal resuscitation strategy for these patients. LEVEL OF EVIDENCE Prognostic, level III.
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Affiliation(s)
| | - Ernest E Moore
- University of Colorado Department of Surgery
- Denver Health Medical Center
| | | | | | | | | | | | | | | | | | | | - Angela Sauaia
- University of Colorado Department of Surgery
- University of Colorado School of Public Health
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Masuda Y, Saotome D, Takada K, Sugimoto K, Sasaki T, Ishii H. Peroxisome proliferator-activated receptor-alpha agonists repress expression of thrombin-activatable fibrinolysis inhibitor by decreasing transcript stability. Thromb Haemost 2017; 108:74-85. [DOI: 10.1160/th12-02-0101] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 04/13/2012] [Indexed: 12/12/2022]
Abstract
SummaryThrombin-activatable fibrinolysis inhibitor (TAFI) (carboxypeptidase B2) is a plasma zymogen that is biosynthesised in the liver and released into the circulation. Activated TAFI is a prothrombotic factor which inhibits fibrin clot lysis. Cultured human hepatoma HepG2 cells were treated with peroxisome proliferator-activated receptor (PPAR)α, β or γ agonists, and the levels of TAFI antigen and mRNA (here, termed CPB2 mRNA) were measured. HepG2 cells treated with the PPARα agonist WY14643, but not agonists for PPARβ or PPARγ, decreased their release of TAFI antigen into the conditioned medium. In parallel, there were decreased levels of CPB2 mRNA and TAFI antigen in the cells. The WY14643-mediated decrease in CPB2 mRNA levels was accelerated by overexpression of PPARα and abolished by RNA interference of PPARA mRNA. CPB2 gene promoter activity was not influenced by treatment of the cells with WY14643. The half-life of the CPB2 transcript was shortened by treatment with WY14643 as compared with that of the control, and the decreased half-life of mRNA returned to control levels by treatment with a PPARα antagonist MK886 or transfection of PPARΑ-specific siRNA to WY14643-treated HepG2 cells. The present results suggest that PPARα agonists not only play a hypolipidaemic role, but also decrease the expression of TAFI, a prothrombotic factor, by decreasing stability of CPB2 transcripts.
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Takada K, Seike T, Sasaki T, Masuda Y, Ito A, Ishii H. Nobiletin, a polymethoxyflavone in citrus fruits, reduces TAFI expression in HepG2 cells through transcriptional inhibition. Thromb Haemost 2017; 109:1060-9. [DOI: 10.1160/th12-08-0597] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 03/04/2013] [Indexed: 11/05/2022]
Abstract
SummaryThrombin-activatable fibrinolysis inhibitor (TAFI, carboxypeptidase B2) is a 58-kDa plasma glycoprotein secreted by hepatocytes as an inactive form. TAFI is activated by the thrombin-thrombomodulin complex, and activated TAFI (TAFIa) plays an important role in regulating the balance between coagulation and fibrinolysis through inhibition of fibrinolysis. It has been suggested that high levels of TAFI in circulating plasma increase the risks of cardiovascular death and acute phase in ischaemic stroke. However, the mechanisms of regulating TAFI expression have been unclear. The present study investigated the effects of nobiletin (a polymethoxy flavonoid contained in the rind of citrus fruits) on TAFI gene (CPB2) and TAFI antigen expression in cultured human hepatoma HepG2 cells. Nobiletin decreased the release of TAFI antigen from HepG2 cells into conditioned medium in parallel with decreased levels of CPB2 mRNA and antigen. The half-life time of CPB2 mRNA in nobiletin-treated cells was unchanged compared to that of untreated control cells. Using nobiletin-treated cells that were transfected with a luciferase CPB2 promoter reporter plasmid, activity decreased to half of that in untreated control cells. A series of luciferase reporter constructs containing 5´-flanking region deletions of the human CPB2 gene showed that the sequences from –150 bp to –50 bp were essential for transcription of CPB2 and contained an AP-1 binding sequence at ∼ –119 bp to – 99 bp in the CPB2 promoter. The amount of complexed nuclear protein and sequences from ∼ –119 bp to –99 bp was decreased in nobiletin-treated cells. ChIP assays showed that c-Jun bound to the ∼ –119 bp to –99 bp region of the CPB2 promoter and that the amount of the immunocomplex decreased after nobiletin treatment. Therefore, nobiletin-induced repression of CPB2 transcription might involve AP-1 inhibition and/or prevention of AP-1 binding in a specific region on the CPB2 gene in HepG2 cells.
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Inhibition of plasmin generation in plasma by heparin, low molecular weight heparin, and a covalent antithrombin–heparin complex. Blood Coagul Fibrinolysis 2017; 28:431-437. [DOI: 10.1097/mbc.0000000000000611] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Association between thrombin-activatable fibrinolysis inhibitor gene polymorphisms and venous thrombosis risk: a meta-analysis. Blood Coagul Fibrinolysis 2017; 27:419-30. [PMID: 26656901 DOI: 10.1097/mbc.0000000000000475] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Thrombin-activatable fibrinolysis inhibitor (TAFI) is an important antifibrinolytic factor that has been shown in increased concentrations to be associated with an increased risk for venous thrombosis. However, the effect of TAFI gene polymorphisms on the risk of venous thrombosis remains debatable. The aim of the current study was to evaluate the association of three single nucleotide polymorphisms: 505G>A (rs3742264), 1040 C>T (rs1926447) and -438G>A (rs2146881) with venous thrombosis risk using a meta-analysis. A systematic literature search for eligible studies published before 20 January 2015 was conducted in PubMed, EMBASE, Web of Science, WanFang database and Chinese National Knowledge Infrastructure. We assessed the possible association by pooled odds ratio and its 95% confidence interval. A total of 14 independent case-control studies including 2970 cases and 3049 controls were enrolled in the final meta-analysis. A significant reduction of venous thrombosis risk in the 505G>A polymorphism was observed under allele comparison, homozygote comparison and recessive models, but opposite results were seen in Asians. Likewise, there was a significant decreased susceptibility to venous thrombosis in the 1040C>T polymorphism in homozygote comparison and recessive models. In the subgroup analysis, the nonvenous thromboembolism disease group showed a significantly increased venous thrombosis risk. Pooled estimates did not show evidence of association between -438G>A and venous thrombosis risk in any genetic model. This meta-analysis suggested that although the -438G>T polymorphism is not correlated with venous thrombosis risk in all models, a trend toward reduced risk still could be observed. The A allele and AA genotype of 505G>A in whites and the TT genotype of 1040C>T were significantly associated with a decreased risk of venous thrombosis, except in the non-venous thromboembolism group.
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Brzoska T, Suzuki Y, Sano H, Suzuki S, Tomczyk M, Tanaka H, Urano T. Imaging analyses of coagulation-dependent initiation of fibrinolysis on activated platelets and its modification by thrombin-activatable fibrinolysis inhibitor. Thromb Haemost 2017; 117:682-690. [PMID: 28150854 DOI: 10.1160/th16-09-0722] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/26/2016] [Indexed: 11/05/2022]
Abstract
Using intravital confocal microscopy, we observed previously that the process of platelet phosphatidylserine (PS) exposure, fibrin formation and lysine binding site-dependent plasminogen (plg) accumulation took place only in the centre of thrombi, not at their periphery. These findings prompted us to analyse the spatiotemporal regulatory mechanisms underlying coagulation and fibrinolysis. We analysed the fibrin network formation and the subsequent lysis in an in vitro experiment using diluted platelet-rich plasma supplemented with fluorescently labelled coagulation and fibrinolytic factors, using confocal laser scanning microscopy. The structure of the fibrin network formed by supplemented tissue factor was uneven and denser at the sites of coagulation initiation regions (CIRs) on PS-exposed platelets. When tissue-type plasminogen activator (tPA; 7.5 nM) was supplemented, labelled plg (50 nM) as well as tPA accumulated at CIRs, from where fibrinolysis started and gradually expanded to the peripheries. The lysis time at CIRs and their peripheries (50 µm from the CIR) were 27.9 ± 6.6 and 44.4 ± 9.7 minutes (mean ± SD, n=50 from five independent experiments) after the addition of tissue factor, respectively. Recombinant human soluble thrombomodulin (TMα; 2.0 nM) attenuated the CIR-dependent plg accumulation and strongly delayed fibrinolysis at CIRs. A carboxypeptidase inhibitor dose-dependently enhanced the CIR-dependent fibrinolysis initiation, and at 20 µM it completely abrogated the TMα-induced delay of fibrinolysis. Our findings are the first to directly present crosstalk between coagulation and fibrinolysis, which takes place on activated platelets' surface and is further controlled by thrombin-activatable fibrinolysis inhibitor (TAFI).
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Affiliation(s)
| | | | | | | | | | | | - Tetsumei Urano
- Dr. Tetsumei Urano, Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handa-yama Higashi-ku Hamamatsu, Shizuoka 431-3192, Japan, Tel.: +81 53 435 2248, Fax: +81 53 435 7020, E-mail:
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Radioprotection as a Method to Enhance the Therapeutic Ratio of Radiotherapy. CANCER DRUG DISCOVERY AND DEVELOPMENT 2017. [DOI: 10.1007/978-3-319-40854-5_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Reduced thrombin activatable fibrinolysis inhibitor and enhanced proinflammatory cytokines in acute coronary syndrome. Med Intensiva 2016; 41:475-482. [PMID: 28038785 DOI: 10.1016/j.medin.2016.10.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 10/09/2016] [Accepted: 10/11/2016] [Indexed: 11/22/2022]
Abstract
OBJECTIVE A study was made of the changes in the serum levels of thrombin activatable fibrinolysis inhibitor (TAFI), proinflammatory cytokines and acute phase proteins in the acute stage of acute coronary syndrome (ACS), in order to explore the possibility of using TAFI as a biomarker for ACS risk assessment. METHODS A total of 211 patients with ACS were enrolled, and healthy subjects were used as controls. Blood samples were taken within 24h after admission. Serum TAFI levels were determined by immunoturbidimetry. Serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were determined by enzyme linked immunosorbent assay (ELISA). Procalcitonin (PCT) and C-reactive protein (CRP) levels were measured by gold-immunochromatographic assay. RESULTS Serum TAFI levels in ACS patients were significantly decreased versus the controls. The IL-1β, IL-6, TNF-α, PCT and CRP levels were markedly higher in the ACS patients than in the controls. Correlation analysis revealed a strong negative correlation between TAFI concentration and the IL-1β, IL-6, TNF-а, PCT and CRP levels in ACS patients and in controls. Multivariate logistic regression analysis suggested decreased serum TAFI to be an independent risk factor for ACS (OR 9.459; 95% CI 2.306-38.793; P=0.002). The area under the receiver operating characteristic (ROC) curve for TAFI was 0.872 (95% CI 0.787-0.909; P<0.001). The optimum TAFI cutoff point for the prediction of ACS was 24μg/ml, with a sensitivity of 75.83% and a specificity of 72.57%. CONCLUSION These findings suggest that TAFI can be useful as a potential biomarker for ACS risk assessment.
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Masuda Y, Yazawa J, Makino Y, Takada K. PI3-Kinase Inhibitor LY294002 Repressed the Expression of Thrombin-Activatable Fibrinolysis Inhibitor in Human Hepatoma HepG2 Cells. Biol Pharm Bull 2016; 38:1529-35. [PMID: 26424017 DOI: 10.1248/bpb.b15-00295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Thrombin-activatable fibrinolysis inhibitor (TAFI) is a carboxypeptidase B-like proenzyme biosynthesized in the liver and released into the blood circulation. Activated TAFI (TAFIa) has been implicated as an important player in maintaining the balance between blood coagulation and fibrinolysis. In the present study, regulation of TAFI (CPB2) gene expression was investigated using cultured human hepatoma HepG2 cells. HepG2 cells were treated with the phosphoinositide 3-kinase (PI3K) inhibitor LY294002, and the levels of TAFI antigen and CPB2 mRNA were measured. HepG2 cells treated with LY29400 decreased their release of TAFI antigen into the conditioned medium (CM). In parallel, there were decreased levels of CPB2 mRNA and TAFI antigen in the cells. However, CPB2 gene promoter activity was not influenced by treatment of the cells with LY294002. The half-life of the CPB2 transcript was shortened by treatment with LY294002 compared with control. The present results suggest that the PI3K inhibitor LY294002 suppresses expression of TAFI, a prothrombotic factor, by decreasing the stability of CPB2 transcripts.
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Affiliation(s)
- Yutaka Masuda
- Laboratory of Clinical Pharmacy, Showa Pharmaceutical University
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Plug T, Meijers JCM. Structure-function relationships in thrombin-activatable fibrinolysis inhibitor. J Thromb Haemost 2016; 14:633-44. [PMID: 26786060 DOI: 10.1111/jth.13261] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Indexed: 11/30/2022]
Abstract
Thrombin-activatable fibrinolysis inhibitor (TAFI) is an important regulator in the balance of coagulation and fibrinolysis. TAFI is a metallocarboxypeptidase that circulates in plasma as zymogen. Activated TAFI (TAFIa) cleaves C-terminal lysine or arginine residues from peptide substrates. The removal of C-terminal lysine residues from partially degraded fibrin leads to reduced plasmin formation and thus attenuation of fibrinolysis. TAFI also plays a role in inflammatory processes via the removal of C-terminal arginine or lysine residues from bradykinin, thrombin-cleaved osteopontin, C3a, C5a and chemerin. TAFI has been studied extensively over the past three decades and recent publications provide a wealth of information, including crystal structures, mutants and structural data obtained with antibodies and peptides. In this review, we combined and compared available data on structure/function relationships of TAFI.
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Affiliation(s)
- T Plug
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - J C M Meijers
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Department of Plasma Proteins, Sanquin Research, Amsterdam, the Netherlands
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Fawzy MS, Toraih EA. Data supporting the structural and functional characterization of Thrombin-Activatable Fibrinolysis Inhibitor in breast cancer. Data Brief 2015; 5:981-9. [PMID: 26740968 PMCID: PMC4675892 DOI: 10.1016/j.dib.2015.10.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 10/19/2015] [Indexed: 11/06/2022] Open
Abstract
The data in this paper is related to the research article entitled “Thrombin-activatable fibrinolysis inhibitor Thr325Ile polymorphism and plasma level in breast cancer: A pilot study” (Fawzy et al., 2015) [1]. Many emerging studies have begun to unravel the pathophysiologic role of the fibrinolytic system in breast cancer (BC) progression (Zorio et al., 2008) [2]. Activation of the fibrinolytic plasminogen/plasmin system results in degradation of protein barriers, thereby mediating cell migration essential for tumor growth, angiogenesis, and dissemination (Castellino and Ploplis, 2005) [3]. In the current study, in silico data analysis of Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) gene and protein has been done. Data have been retrieved from several databases mentioned in details in the text. Determination and analysis of the structural and functional impact of TAFI and its expression could help elucidate the contribution of the TAFI pathway to acquired hemostatic dysfunction and will form the basis of potential therapeutic strategies to manipulate this pathway. An inhibition of TAFI (e.g. by FXI inhibitors) will offer the therapeutic possibilities to improve the decreased fibrinolysis and increase the efficiency of fibrinolytic therapy in thrombotic disorders including cancer.
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Affiliation(s)
- Manal S Fawzy
- Department of Medical Biochemistry, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Eman A Toraih
- Department of Histology and Cell Biology (Genetics Unit), Faculty of Medicine, Suez Canal University, Ismailia, Egypt
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Plug T, Marquart JA, Marx PF, Meijers JCM. Selective modulation of thrombin-activatable fibrinolysis inhibitor (TAFI) activation by thrombin or the thrombin-thrombomodulin complex using TAFI-derived peptides. J Thromb Haemost 2015; 13:2093-101. [PMID: 26341360 DOI: 10.1111/jth.13133] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND Thrombin-activatable fibrinolysis inhibitor (TAFI) is a risk factor for coronary heart disease. TAFI is proteolytically activated by thrombin, the thrombin-thrombomodulin complex and plasmin. Once active, it dampens fibrinolysis and inflammation. The aim of this study was to generate TAFI-derived peptides that specifically modulate TAFI activation and activity. METHODS Thirty-four overlapping TAFI peptides, and modifications thereof, were synthesized. The effects of these peptides on TAFI activation and TAFIa activity were determined. In addition, the binding of the peptides to thrombin were determined. RESULTS Four peptides (peptides 2, 18, 19 and 34) inhibited TAFI activation and two peptides (peptides 14 and 24) inhibited TAFIa activity directly. Peptide 2 (Arg12-Glu28) and peptide 34 (Cys383-Val401) inhibited TAFI activation by the thrombin-thrombomodulin complex with IC50 values of 7.3 ± 1.8 and 6.1 ± 0.9 μm, respectively. However, no inhibition was observed in the absence of thrombomodulin. This suggests that the regions Arg12-Glu28 and Cys383-Val401 in TAFI are involved in thrombomodulin-mediated TAFI activation. Peptide 18 (Gly205-Ser221) and peptide 19 (Arg214-Asp232) inhibited TAFI activation by thrombin and the thrombin-thrombomodulin complex. Furthermore, these peptides bound to thrombin (KD : 1.5 ± 0.4 and 0.52 ± 0.07 μm for peptides 18 and 19, respectively), suggesting that Gly205-Asp232 of TAFI is involved in binding to thrombin. Peptide 14 (His159-His175) inhibited TAFIa activity. The inhibition was TAFIa specific, because no effect on the homologous enzyme carboxypeptidase B was observed. CONCLUSIONS Thrombin-activatable fibrinolysis inhibitor-derived peptides show promise as new tools to modulate TAFI activation and TAFIa activity. Furthermore, these peptides revealed potential binding sites on TAFI for thrombin and the thrombin-thrombomodulin complex.
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Affiliation(s)
- T Plug
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - J A Marquart
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Department of Plasma Proteins, Sanquin Research, Amsterdam, the Netherlands
| | - P F Marx
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - J C M Meijers
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Department of Plasma Proteins, Sanquin Research, Amsterdam, the Netherlands
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15
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Plug T, Meijers JCM. New clues regarding the mysterious mechanism of activated thrombin-activatable fibrinolysis inhibitor self-destruction. J Thromb Haemost 2015; 13:1081-3. [PMID: 25777152 DOI: 10.1111/jth.12900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 03/02/2015] [Indexed: 12/01/2022]
Affiliation(s)
- T Plug
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - J C M Meijers
- Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Department of Plasma Proteins, Sanquin Research, Amsterdam, the Netherlands
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16
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Plug T, Kramer G, Meijers JCM. A role for arginine-12 in thrombin-thrombomodulin-mediated activation of thrombin-activatable fibrinolysis inhibitor. J Thromb Haemost 2014; 12:1717-25. [PMID: 25066897 DOI: 10.1111/jth.12674] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 07/14/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND Thrombin-activatable fibrinolysis inhibitor (TAFI) is a proenzyme that links coagulation and fibrinolysis. TAFI can be activated by thrombin, the thrombin-thrombomodulin complex and plasmin through cleavage of the first 92 amino acids from the enzyme. In silico analysis of the TAFI sequence revealed a potential thrombin cleavage site at Arg12. The aim of this study was to determine whether TAFI can be cleaved at Arg12 and whether this cleavage plays a role in TAFI activation. METHODS A peptide based on the first 18 amino acids of TAFI was used to determine whether thrombin was able to cleave at Arg12. Mass spectrometry was performed to determine whether the Arg12-cleaved peptide was released from full-length TAFI. Furthermore, a TAFI mutant in which Arg12 was replaced by a glutamine (TAFI-R12Q) was constructed and characterized with respect to its activation kinetics. RESULTS The peptide and mass spectrometry data showed that thrombin was able to cleave TAFI at Arg12, but with low efficiency in full-length TAFI. Characterization of TAFI-R12Q showed no difference in thrombin-mediated activation from wild-type TAFI. However, there was an approximately 60-fold impairment in activation of TAFI-R12Q by the thrombin-thrombomodulin complex. CONCLUSIONS Arg12 of TAFI plays an important role in thrombomodulin-mediated TAFI activation by thrombin. Thrombin is able to cleave TAFI at Arg12, but it remains to be determined whether Arg12 is part of an exosite for thrombomodulin or whether cleavage at Arg12 accelerates thrombomodulin-mediated TAFI activation.
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Affiliation(s)
- T Plug
- Department of Experimental Vascular Medicine, Academic Medical Center, Amsterdam, The Netherlands
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17
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Brink M, Dahlén A, Olsson T, Polla M, Svensson T. Design and synthesis of conformationally restricted inhibitors of active thrombin activatable fibrinolysis inhibitor (TAFIa). Bioorg Med Chem 2014; 22:2261-8. [PMID: 24588961 DOI: 10.1016/j.bmc.2014.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/15/2014] [Accepted: 02/10/2014] [Indexed: 10/25/2022]
Abstract
A series of 4,5,6,7-tetrahydro-1H-benzimidazole-5-carboxylic acid and 5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-7-carboxylic acid derivatives designed as inhibitors of TAFIa has been prepared via a common hydrogenation-alkylation sequence starting from the appropriate benzimidazole and imidazopyridine system. We present a successful design strategy using a conformational restriction approach resulting in potent and selective inhibitors of TAFIa. The X-ray structure of compound 5 in complex with a H333Y/H335Q double mutant TAFI indicate that the conformational restriction is responsible for the observed potency increase.
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Affiliation(s)
- Mikael Brink
- Cardiovascular and Metabolic Disorders Research Area, AstraZeneca R&D Mölndal, SE-431 83 Mölndal, Sweden
| | - Anders Dahlén
- Cardiovascular and Metabolic Disorders Research Area, AstraZeneca R&D Mölndal, SE-431 83 Mölndal, Sweden
| | - Thomas Olsson
- Cardiovascular and Metabolic Disorders Research Area, AstraZeneca R&D Mölndal, SE-431 83 Mölndal, Sweden
| | - Magnus Polla
- Cardiovascular and Metabolic Disorders Research Area, AstraZeneca R&D Mölndal, SE-431 83 Mölndal, Sweden.
| | - Tor Svensson
- Cardiovascular and Metabolic Disorders Research Area, AstraZeneca R&D Mölndal, SE-431 83 Mölndal, Sweden
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18
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Hendrickx MLV, Zatloukalova M, Hassanzadeh-Ghassabeh G, Muyldermans S, Gils A, Declerck PJ. Identification of a novel, nanobody-induced, mechanism of TAFI inactivation and its in vivo application. J Thromb Haemost 2014; 12:229-36. [PMID: 24354544 DOI: 10.1111/jth.12473] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Down-regulation of fibrinolysis due to cleavage of C-terminal lysine residues from partially degraded fibrin is mainly exerted by the carboxypeptidase activity of activated thrombin-activatable fibrinolysis inhibitor (TAFIa). Recently, some intrinsic carboxypeptidase activity (i.e. zymogen activity) was reported for the proenzyme (TAFI); however, there is some discussion about its ability to cleave high molecular weight substrates. OBJECTIVE We aimed to identify and characterize nanobodies toward mouse TAFI (mTAFI) that stimulate the zymogen activity and to test their effect in an in vitro clot lysis assay and an in vivo mouse thromboembolism model. METHODS AND RESULTS Screening of a library of nanobodies toward mTAFI revealed one nanobody (VHH-mTAFI-i49) that significantly stimulates the zymogen activity of mTAFI from undetectable (< 0.35 U mg⁻¹) to 4.4 U mg⁻¹ (at a 16-fold molar ratio over mTAFI). The generated carboxypeptidase activity is unstable at 37 °C. Incubation of mTAFI with VHH-mTAFI-i49 revealed a time-dependent reduced activatability of mTAFI. Epitope mapping revealed that Arg227 and Lys212 are important for the nanobody/mTAFI interaction and suggest destabilization of mTAFI by disrupting the stabilizing interaction between the activation peptide and the dynamic flap region. In vitro clot lysis experiments revealed an enhanced clot lysis due to a reduced activation of mTAFI during clot formation. In vivo application of VHH-mTAFI-i49 in a mouse thromboembolism model decreased dose-dependently the fibrin deposition in the lungs of thromboembolism-induced mice. CONCLUSION The novel, nanobody-induced, reduced activatability of mTAFI demonstrates to be a very potent approach to enhance clot lysis.
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Affiliation(s)
- M L V Hendrickx
- Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Brussels, Belgium
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19
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Yoshimoto N, Itoh T, Inaba Y, Ishii H, Yamamoto K. Structural Basis for Inhibition of Carboxypeptidase B by Selenium-Containing Inhibitor: Selenium Coordinates to Zinc in Enzyme. J Med Chem 2013; 56:7527-35. [DOI: 10.1021/jm400816v] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nobuko Yoshimoto
- High
Technology Research Center, ‡Laboratory of Drug Design and Medicinal Chemistry and §Laboratory of
Molecular and Cellular Pathophysiology, Showa Pharmaceutical University, 3-3165
Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Toshimasa Itoh
- High
Technology Research Center, ‡Laboratory of Drug Design and Medicinal Chemistry and §Laboratory of
Molecular and Cellular Pathophysiology, Showa Pharmaceutical University, 3-3165
Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Yuka Inaba
- High
Technology Research Center, ‡Laboratory of Drug Design and Medicinal Chemistry and §Laboratory of
Molecular and Cellular Pathophysiology, Showa Pharmaceutical University, 3-3165
Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Hidemi Ishii
- High
Technology Research Center, ‡Laboratory of Drug Design and Medicinal Chemistry and §Laboratory of
Molecular and Cellular Pathophysiology, Showa Pharmaceutical University, 3-3165
Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Keiko Yamamoto
- High
Technology Research Center, ‡Laboratory of Drug Design and Medicinal Chemistry and §Laboratory of
Molecular and Cellular Pathophysiology, Showa Pharmaceutical University, 3-3165
Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
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20
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Binding of carboxypeptidase N to fibrinogen and fibrin. Biochem Biophys Res Commun 2012; 427:421-5. [DOI: 10.1016/j.bbrc.2012.09.081] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 09/12/2012] [Indexed: 11/18/2022]
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21
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Yoshimoto N, Sasaki T, Sugimoto K, Ishii H, Yamamoto K. Design and characterization of a selenium-containing inhibitor of activated thrombin-activatable fibrinolysis inhibitor (TAFIa), a zinc-containing metalloprotease. J Med Chem 2012; 55:7696-705. [PMID: 22891675 DOI: 10.1021/jm300735t] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Available therapies for thromboembolic disorders include thrombolytics, anticoagulants, and antiplatelets, but these are associated with complications such as bleeding. To develop an alternative drug which is clinically safe, we focused on activated thrombin-activatable fibrinolysis inhibitor (TAFIa) as the target molecule. TAFIa is a zinc-containing carboxypeptidase that significantly inhibits fibrinolysis. Here we designed and synthesized selenium-containing compounds 5-13 to discover novel TAFIa inhibitors having a superior zinc-coordinating group. Compounds 5-13 significantly inhibited TAFIa activity (IC(50) 2.2 × 10(-12) M - 2.6 × 10(-6) M). We found that selenol is a better functional group than thiol for coordinating to zinc at the active site of TAFIa. Furthermore, compound 12, which has an amino-chloro-pyridine ring, was found to be a potent and selective TAFIa inhibitor that lacks carboxypeptidase N inhibitory activity. Therefore, compound 12 is a promising candidate for the treatment of thromboembolic disorders. This is the first report of a selenium-containing inhibitor for TAFIa.
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Affiliation(s)
- Nobuko Yoshimoto
- High Technology Research Center, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan.
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22
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Ozkan G, Ulusoy S, Sönmez M, Karahan SC, Menteşe A, Kaynar K, Bektaş O. Thrombin activatable fibrinolysis inhibitor (TAFI) levels in hypertensive patients and a comparison of the effects of amlodipine and ramipril on TAFI levels. Clin Exp Hypertens 2012; 35:134-40. [PMID: 22799880 DOI: 10.3109/10641963.2012.702833] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Hypertension is associated with fibrinolysis abnormality. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a novel molecule-linking coagulation and fibrinolysis. The aim of this study was to investigate the levels of TAFI in primary hypertensive patients and to compare the effects of amlodipine and ramipril on TAFI levels. The study was performed with 58 hypertensive subjects and 27 healthy volunteers. Biochemical and hematological parameters and TAFI levels were measured at baseline and after 1-month follow-up. TAFI concentrations increased in hypertensive patients compared with the controls (P = .030). Additionally, TAFI levels decreased with blood pressure control at 1-month follow-up (P = .026). There was no significant difference between TAFI levels in the amlodipine and ramipril groups at baseline. However, after 1-month follow-up, TAFI levels were decreased in the amlodipine group (P = .037) but not in the ramipril group. Our study is the first in the literature to determine increased TAFI levels in primary hypertension patients. In addition, we determined a decrease in TAFI levels in the amlodipine group after 1 month, but none in the ramipril group.
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Affiliation(s)
- Gulsum Ozkan
- Department of Nephrology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey.
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23
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Sasaki T, Yoshimoto N, Sugimoto K, Takada K, Murayama N, Yamazaki H, Yamamoto K, Ishii H. Intravenous and oral administrations of DD2 [7-Amino-2-(sulfanylmethyl)heptanoic acid] produce thrombolysis through inhibition of plasma TAFIa in rats with tissue factor-induced microthrombosis. Thromb Res 2012; 130:e222-8. [PMID: 22795218 DOI: 10.1016/j.thromres.2012.06.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 06/03/2012] [Accepted: 06/13/2012] [Indexed: 12/24/2022]
Abstract
Thrombin-activatable fibrinolysis inhibitor (TAFI) is a plasma zymogen that is activated by thrombin in plasma. In fibrinolytic processes, carboxy-terminal lysine (Lys) residues in partially degraded fibrin are important sites for plasminogen binding and activation, and an active form of TAFI (TAFIa) inhibits fibrinolysis by eliminating these residues proteolytically. We synthesized DD2 [7-Amino-2-(sulfanylmethyl)heptanoic acid], a Lys analogue containing sulfur, as an inhibitor of TAFIa and investigated its pharmacological profile and pathophysiological role in thrombolysis via in vitro and in vivo studies. DD2 specifically inhibited plasma TAFIa activity with an apparent IC(50) (50% inhibitory concentration) value of 3.4×10(-8)M under the present experimental condition and enhanced tissue plasminogen activator-mediated clot lysis in a concentration-dependent manner. In order to study tissue factor (TF)-induced microthrombosis in an animal model, rats were given intravenous injection (2.5mg/kg and higher) or oral administration (10mg/kg and higher) of DD2. This attenuated TF-induced glomerular fibrin deposition and increased the plasma levels of fibrin degradation products and D-dimer in a dose-dependent manner. A DD2 dose approximately 4X higher than the dose used in intravenous injections was required to achieve an equivalent thrombolytic effect to that seen following oral administration. Moreover, the oral absorption efficiency of DD2 into the vasculature was 29.8%. These results indicate that both intravenous and oral administration of DD2 enhanced endogenous fibrinolysis and reduced thrombi in a TF-induced microthrombosis model.
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Affiliation(s)
- Tomoyuki Sasaki
- High Technology Research Center, Showa Pharmaceutical University, 3-3165 Higashi Tamagawa Gakuen, Machida, Tokyo 194-8543, Japan
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24
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Fidan E, Kavgaci H, Orem A, Yilmaz M, Yildiz B, Fidan S, Akcan B, Ozdemir F, Aydin F. Thrombin activatable fibrinolysis inhibitor and thrombin-antithrombin-III-complex levels in patients with gastric cancer. Tumour Biol 2012; 33:1519-25. [PMID: 22535370 DOI: 10.1007/s13277-012-0403-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 04/13/2012] [Indexed: 10/28/2022] Open
Abstract
The relation between cancer and coagulation is the subject of investigation since a relation between tumor and thrombosis has been determined. Antithrombin III is an important thrombin inhibitor, and increased thrombin-antithrombin (TAT) complex levels activate coagulation. Activated thrombin activatable fibrinolysis inhibitor (TAFI) inhibits the conversion of plasminogen to plasmin. In addition, it directly inactivates plasmin. Defective fibrinolysis increases the risk of thrombosis. In this study, we evaluated homeostatic parameters, TAFI, and TAT levels in patients with gastric cancer applying to the medical oncology outpatient clinic. Fifty-two patients and 35 healthy controls were included. ELISA was used to measure TAFI and TAT complex levels. These were statistically higher in the patient group (p < 0.05 and p = 0.001, respectively). D-dimer levels were higher in stage IV (p = 0.05). Correlations between lymph nodes and TAFI and TAT levels were examined. Weak but positive correlation between lymph nodes and TAFI was detected (R = 0.452, p = 0.027). TAFI and TAT levels were evaluated using relative operating characteristic analysis to differentiate the disease. TAT was more specific than TAFI according to this analysis (TAFI area under curve (AUC), 0.676; TAT AUC, 0.874). Thrombotic events and bleeding disorders need to be borne in mind in gastric cancer. This situation is due to the impairment of the balance between coagulation and fibrinolysis. Further studies are now needed to evaluate the effects of TAFI and TAT on survey and prognosis as well as the potential of these parameters as tumor markers for gastric cancer.
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Affiliation(s)
- Evren Fidan
- Division of Medical Oncology, School of Medicine, Karadeniz Technical University, 61080, Trabzon, Turkey.
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25
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Kim PY, Kim PYG, Taylor FB, Nesheim ME. Thrombin-activatable fibrinolysis inhibitor is activated in vivo in a baboon model of Escherichia coli induced sepsis. J Thromb Thrombolysis 2012; 33:412-5. [DOI: 10.1007/s11239-011-0676-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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26
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Orbe J, Barrenetxe J, Rodriguez JA, Vivien D, Orset C, Parks WC, Birkland TP, Serrano R, Purroy A, Martinez de Lizarrondo S, Angles-Cano E, Páramo JA. Matrix metalloproteinase-10 effectively reduces infarct size in experimental stroke by enhancing fibrinolysis via a thrombin-activatable fibrinolysis inhibitor-mediated mechanism. Circulation 2011; 124:2909-19. [PMID: 22104553 DOI: 10.1161/circulationaha.111.047100] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The fibrinolytic and matrix metalloproteinase (MMP) systems cooperate in thrombus dissolution and extracellular matrix proteolysis. The plasminogen/plasmin system activates MMPs, and some MMPs have been involved in the dissolution of fibrin by targeting fibrin(ogen) directly or by collaborating with plasmin. MMP-10 has been implicated in inflammatory/thrombotic processes and vascular integrity, but whether MMP-10 could have a profibrinolytic effect and represent a promising thrombolytic agent is unknown. METHODS AND RESULTS The effect of MMP-10 on fibrinolysis was studied in vitro and in vivo, in MMP-10-null mice (Mmp10(-/-)), with the use of 2 different murine models of arterial thrombosis: laser-induced carotid injury and ischemic stroke. In vitro, we showed that MMP-10 was capable of enhancing tissue plasminogen activator-induced fibrinolysis via a thrombin-activatable fibrinolysis inhibitor inactivation-mediated mechanism. In vivo, delayed fibrinolysis observed after photochemical carotid injury in Mmp10(-/-) mice was reversed by active recombinant human MMP-10. In a thrombin-induced stroke model, the reperfusion and the infarct size in sham or tissue plasminogen activator-treated animals were severely impaired in Mmp10(-/-) mice. In this model, administration of active MMP-10 to wild-type animals significantly reduced blood reperfusion time and infarct size to the same extent as tissue plasminogen activator and was associated with shorter bleeding time and no intracranial hemorrhage. This effect was not observed in thrombin-activatable fibrinolysis inhibitor-deficient mice, suggesting thrombin-activatable fibrinolysis inhibitor inactivation as one of the mechanisms involved in the MMP-10 profibrinolytic effect. CONCLUSIONS A novel profibrinolytic role for MMP-10 in experimental ischemic stroke is described, opening new pathways for innovative fibrinolytic strategies in arterial thrombosis.
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Affiliation(s)
- J Orbe
- Laboratory of Atherosclerosis, Division of Cardiovascular Science, CIMA, Avenida Pio XII, 55, 31008 Pamplona, Navarra, Spain.
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27
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Declerck PJ. Thrombin activatable fibrinolysis inhibitor. Hamostaseologie 2011; 31:165-6, 168-73. [PMID: 21629966 DOI: 10.5482/ha-1155] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Accepted: 05/26/2011] [Indexed: 12/14/2022] Open
Abstract
Thrombin activatable fibrinolysis inhibitor (TAFI) was discovered two decades ago as a consequence of the identification of an unstable carboxypeptidase (CPU), which was formed upon thrombin activation of the respective pro-enzyme (proCPU). The antifibrinolytic function of the activated form (TAFIa, CPU) is directly linked to its capacity to remove C-terminal lysines from the surface of the fibrin clot. No endogenous inhibitors have been identified, but TAFIa activity is regulated by its intrinsic temperature-dependent instability with a half-life of 8 to 15 min at 37 °C. A variety of studies have demonstrated a role for TAFI/TAFIa in venous and arterial diseases. In addition, a role in inflammation and cell migration has been shown. Since an elevated level of TAFIa it is a potential risk factor for thrombotic disorders, many inhibitors, both at the level of activation or at the level of activity, have been developed and were proven to exhibit a profibrinolytic effect in animal models. Pharmacologically active inhibitors of the TAFI/TAFIa system may open new ways for the prevention of thrombotic diseases or for the establishment of adjunctive treatments during thrombolytic therapy.
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Affiliation(s)
- P J Declerck
- Katholieke Universiteit Leuven, Campus Gasthuisberg, Herestraat 49, Leuven, Belgium.
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28
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Mishra N, Vercauteren E, Develter J, Bammens R, Declerck PJ, Gils A. Identification and characterisation of monoclonal antibodies that impair the activation of human thrombin activatable fibrinolysis inhibitor through different mechanisms. Thromb Haemost 2011; 106:90-101. [PMID: 21544309 DOI: 10.1160/th10-08-0546] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 03/18/2011] [Indexed: 11/05/2022]
Abstract
Thrombin activatable fibrinolysis inhibitor (TAFI) forms a molecular link between coagulation and fibrinolysis and is a putative target to develop profibrinolytic drugs. Out of a panel of monoclonal antibodies (MA) raised against TAFI-ACIIYQ, we selected MA-TCK11A9, MA-TCK22G2 and MA-TCK27A4, which revealed high affinity towards human TAFI-TI-wt. MA-TCK11A9 was able to inhibit mainly plasmin-mediated TAFI activation, MA-TCK22G2 inhibited plasmin- and thrombin-mediated TAFI activation and MA-TCK27A4 inhibited TAFI activation by plasmin, thrombin and thrombin/thrombomodulin (T/TM) in a dose-dependent manner. These MA did not interfere with TAFIa activity. Using an eight-fold molar excess of MA over TAFI, all three MA were able to reduce clot lysis time significantly, i.e. in the presence of exogenous TM, MA-TCK11A9, MA-TCK22G2 and MA-TCK27A4 reduced clot lysis time by 47 ± 9.1%, 80 ± 8.6% and 92 ± 14%, respectively, compared to PTCI. This effect was even more pronounced in the absence of TM i.e. MA-TCK11A9, MA-TCK22G2 and MA-TCK27A4 reduced clot lysis time by 90 ± 14%, 140 ± 12% and 147 ± 29%, respectively, compared to PTCI. Mutagenesis analysis revealed that residues at position 268, 272 and 276 are involved in the binding of MA-TCK11A9, residues 147 and 148 in the binding of MA-TCK22G2 and residue 113 in the binding of MA-TCK27A4. The present study identified three MA, with distinct epitopes, that impair the activation of human TAFI and demonstrated that MA-TCK11A9 which mainly impairs plasmin-mediated TAFI activation can also reduce significantly clot lysis time in vitro.
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Affiliation(s)
- Niraj Mishra
- Laboratory for Pharmaceutical Biology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, O&N II, Leuven, Belgium
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Borowiecka M, Polac I, Nowak P, Radwan P, Ponczek MB, Wachowicz B. Changes in Hemostatic Parameters After Oral Hormone Therapy in Postmenopausal Women. J Womens Health (Larchmt) 2010; 19:2267-70. [DOI: 10.1089/jwh.2010.2040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Marta Borowiecka
- Department of General Biochemistry, University of Lodz, Lodz, Poland
| | - Ireneusz Polac
- Department of Gynaecology and Menopausal Disorders ICZMP, Lodz, Poland
| | - Pawel Nowak
- Department of General Biochemistry, University of Lodz, Lodz, Poland
| | | | - Michal B. Ponczek
- Department of General Biochemistry, University of Lodz, Lodz, Poland
| | - Barbara Wachowicz
- Department of General Biochemistry, University of Lodz, Lodz, Poland
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Jessen LR, Wiinberg B, Kjelgaard-Hansen M, Jensen AL, Rozanski E, Kristensen AT. ORIGINAL RESEARCH: Thrombin-activatable fibrinolysis inhibitor activity in healthy and diseased dogs. Vet Clin Pathol 2010; 39:296-301. [DOI: 10.1111/j.1939-165x.2010.00230.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Quagraine M, Tan F, Tamei H, Erdös E, Skidgel R. Plasmin alters the activity and quaternary structure of human plasma carboxypeptidase N. Biochem J 2009; 388:81-91. [PMID: 15617514 PMCID: PMC1186696 DOI: 10.1042/bj20041471] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Human CPN (carboxypeptidase N) is a tetrameric plasma enzyme containing two glycosylated 83 kDa non-catalytic/regulatory subunits that carry and protect two active catalytic subunits. Because CPN can regulate the level of plasminogen binding to cell surface proteins, we investigated how plasmin cleaves CPN and the consequences. The products of hydrolysis were analysed by activity assays, Western blotting, gel filtration and sequencing. When incubated with intact CPN tetramer, plasmin rapidly cleaved the 83 kDa subunit at the Arg457-Ser458 bond near the C-terminus to produce fragments of 72 and 13 kDa, thereby releasing an active 142 kDa heterodimer, and also cleaved the active subunit, decreasing its size from 55 kDa to 48 kDa. Further evidence for the heterodimeric form of CPN was obtained by re-complexing the non-catalytic 72 kDa fragment with recombinant catalytic subunit or by immunoprecipitation of the catalytic subunit after plasmin treatment of CPN using an antibody specific for the 83 kDa subunit. Upon longer incubation, plasmin cleaved the catalytic subunit at Arg218-Arg219 to generate fragments of 27 kDa and 21 kDa, held together by non-covalent bonds, that were more active than the native enzyme. These data show that plasmin can alter CPN structure and activity, and that the C-terminal 13 kDa fragment of the CPN 83 kDa subunit is a docking peptide that is necessary to maintain the stable active tetrameric form of human CPN in plasma.
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Affiliation(s)
- Mercy O. Quagraine
- *Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
| | - Fulong Tan
- *Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
- †Department of Anesthesiology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
| | - Hironori Tamei
- *Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
| | - Ervin G. Erdös
- *Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
- †Department of Anesthesiology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
| | - Randal A. Skidgel
- *Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
- †Department of Anesthesiology, University of Illinois College of Medicine, Chicago, IL 60612, U.S.A
- To whom correspondence should be addressed: Department of Pharmacology (M/C 868), University of Illinois College of Medicine, 835 S. Wolcott, Chicago, IL 60612, U.S.A. (email )
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Falk K, BjÖrquist P, Falk P, Hedgren M, Ivarsson M, Lanne B, Panfilov O, Holmdahl L. Antifibrinolytic proCPU is present in the peritoneal cavity during surgery. Scandinavian Journal of Clinical and Laboratory Investigation 2009. [DOI: 10.1080/00365510310001726] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
Factor XI (FXI) deficiency is an autosomal recessive injury-related bleeding tendency, which is common in Jews particularly of Ashkenazi origin. To date, 152 mutations in the FXI gene have been reported with four exhibiting founder effects in specific populations, Glu117stop in Ashkenazi and Iraqi Jews and Arabs, Phe283Leu in Ashkenazi Jews, Cys38Arg in Basques, and Cys128stop in the United Kingdom. Severe FXI deficiency does not confer protection against acute myocardial infarction, but is associated with a reduced incidence of ischemic stroke. Inhibitors to FXI develop in one-third of patients with very severe FXI deficiency following exposure to blood products. Therapy for prevention of bleeding during surgery in patients with severe FXI deficiency consists of plasma, factor XI concentrates, fibrin glue and antifibrinolytic agents. In patients with an inhibitor to FXI, recombinant factor VIIa is useful.
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Affiliation(s)
- U Seligsohn
- Amalia Biron Research Institute of Thrombosis and Hemostasis, Sheba Medical Center, Tel Hashomer, Israel.
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Higuchi T, Nakamura T, Kakutani H, Ishii H. Thrombomodulin suppresses invasiveness of HT1080 tumor cells by reducing plasminogen activation on the cell surface through activation of thrombin-activatable fibrinolysis inhibitor. Biol Pharm Bull 2009; 32:179-85. [PMID: 19182372 DOI: 10.1248/bpb.32.179] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cell malignancy is negatively correlated with the expression of thrombomodulin (TM), a thrombin receptor expressed on the surface of various cells, including tumor cells. TM accelerates thrombin-activatable fibrinolysis inhibitor (TAFI) activation catalyzed by thrombin. The active form of TAFI (TAFIa) contributes to inhibition of plasmin formation through its carboxypeptidase B (CPB)-like activity. Here, we examined whether TM- and tumor cell-dependent TAFI activation participates in controlling pericellular fibrinolysis and cell invasion. Human fibrosarcoma HT1080 cells retained the ability to activate both prothrombin and plasminogen, but did not express TM. HT1080 cells mediated activation of TAFI in plasma in the presence of soluble-type TM (sTM) through cell-dependent prothrombin activation. HT1080 cells stably expressing TM (TM-HT1080) mediated plasma TAFI activation without added sTM, but HT1080 (wild-type) and Mock-transfected HT1080 cells (Mock) did not. Production of TAFIa suppressed cell-mediated plasminogen activation. Matrigel invasion by wild-type and Mock cells was enhanced two-fold by diluted plasma (10%), whereas the plasma-induced invasion of TM-HT1080 cells (65% of wild-type invasion) was lower than those of wild-type and Mock cells. Cell invasion by TM-HT1080 was partially enhanced by addition of a TAFIa/CPB inhibitor. These results suggest that TM suppresses pericellular fibrinolysis and plasma-induced tumor cell invasion, and that it is mediated, at least in part, by plasma TAFI activation.
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Affiliation(s)
- Toshiyuki Higuchi
- Department of Molecular and Cellular Pathophysiology, Showa Pharmaceutical University, Tokyo, Japan.
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Binding of Thrombin Activatable Fibrinolysis Inhibitor (TAFI) to Plasminogen May Play a Role in the Fibrinolytic Pathway. B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.11.2209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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36
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Anand K, Pallares I, Valnickova Z, Christensen T, Vendrell J, Wendt KU, Schreuder HA, Enghild JJ, Avilés FX. The crystal structure of thrombin-activable fibrinolysis inhibitor (TAFI) provides the structural basis for its intrinsic activity and the short half-life of TAFIa. J Biol Chem 2008; 283:29416-23. [PMID: 18669641 PMCID: PMC2662027 DOI: 10.1074/jbc.m804003200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Revised: 06/17/2008] [Indexed: 11/06/2022] Open
Abstract
Mature thrombin-activable fibrinolysis inhibitor (TAFIa) is a highly unstable metallocarboxypeptidase that stabilizes blood clots by clipping C-terminal lysine residues from partially degraded fibrin. In accordance with its in vitro antifibrinolytic activity, animal studies have reported that inhibition of mature TAFI aids in the prevention of thrombosis. The level of TAFI activity is stringently regulated through (i) controlled proteolytic truncation of the zymogen (TAFI), generating the mature enzyme, TAFIa, and (ii) the short half-life of TAFIa. TAFI itself exhibits an intrinsic enzymatic activity, which is likely required to provide a baseline level of antifibrinolytic activity. The novel crystal structure presented here reveals that the active site of TAFI is accessible, providing the structural explanation for the its intrinsic activity. It also supports the notion that an "instability region" exists, in agreement with site-directed mutagenesis studies. Sulfate ions, bound to this region, point toward a potential heparin-binding site and could explain how heparin stabilizes TAFIa.
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Affiliation(s)
- Kanchan Anand
- Sanofi-Aventis Pharma Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
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37
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Martínez-Montemayor MM, Hill GM, Raney NE, Rilington VD, Tempelman RJ, Link JE, Wilkinson CP, Ramos AM, Ernst CW. Gene expression profiling in hepatic tissue of newly weaned pigs fed pharmacological zinc and phytase supplemented diets. BMC Genomics 2008; 9:421. [PMID: 18799003 PMCID: PMC2566318 DOI: 10.1186/1471-2164-9-421] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2008] [Accepted: 09/17/2008] [Indexed: 12/17/2022] Open
Abstract
Background Zinc (Zn) is an essential trace element. However, Zn bioavailability from commonly consumed plants may be reduced due to phytic acid. Zn supplementation has been used to treat diarrheal disease in children, and in the U.S. swine industry at pharmacological levels to promote growth and fecal consistency, but underlying mechanisms explaining these beneficial effects remain unknown. Moreover, adding supplemental phytase improves Zn bioavailability. Thus, we hypothesized that benefits of pharmacological Zn supplementation result from changes in gene expression that could be further affected by supplemental phytase. The goal of this study was to investigate the effects of feeding newly weaned pigs dietary Zn (150, 1,000, or 2,000 mg Zn/kg) as Zn oxide with or without phytase [500 phytase units (FTU)/kg] for 14 d on hepatic gene expression. Liver RNA from pigs fed 150, 1,000, or 2,000 mg Zn/kg, or 1,000 mg Zn/kg with phytase (n = 4 per treatment) was reverse transcribed and examined using the differential display reverse transcription polymerase chain reaction technique. Liver RNA from pigs fed 150 or 2,000 mg Zn/kg (n = 4 per treatment) was also evaluated using a 70-mer oligonucleotide microarray. Results Expressed sequence tags for 61 putatively differentially expressed transcripts were cloned and sequenced. In addition, interrogation of a 13,297 element oligonucleotide microarray revealed 650 annotated transcripts (FDR ≤ 0.05) affected by pharmacological Zn supplementation. Seven transcripts exhibiting differential expression in pigs fed pharmacological Zn with sequence similarities to genes encoding GLO1, PRDX4, ACY1, ORM1, CPB2, GSTM4, and HSP70.2 were selected for confirmation. Relative hepatic GLO1 (P < 0.0007), PRDX4 (P < 0.009) and ACY1 (P < 0.01) mRNA abundances were confirmed to be greater in pigs fed 1,000 (n = 8) and 2,000 (n = 8) mg Zn/kg than in pigs fed 150 (n = 7) mg Zn/kg. Relative hepatic HSP70.2 (P < 0.002) mRNA abundance was confirmed to be lower in pigs fed 2,000 mg Zn/kg than in pigs fed 150 or 1,000 mg Zn/kg. Conclusion Results suggest that feeding pharmacological Zn (1,000 or 2,000 mg Zn/kg) affects genes involved in reducing oxidative stress and in amino acid metabolism, which are essential for cell detoxification and proper cell function.
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Sabater-Lleal M, Buil A, Souto JC, Alamsy L, Borrell M, Lathrop M, Blangero J, Fontcuberta J, Soria JM. A genome-wide exploration suggests an oligogenic model of inheritance for the TAFI activity and its antigen levels. Hum Genet 2008; 124:81-8. [PMID: 18563448 DOI: 10.1007/s00439-008-0527-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Accepted: 06/12/2008] [Indexed: 11/29/2022]
Abstract
Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) is a protein that potently attenuates fibrinolysis. A considerable proportion of its variability levels is genetically determined. It has been associated with arterial and venous thrombosis. We conducted a Genome Wide Scan for genes affecting variation in plasma TAFI levels in 398 subjects from 21 extended Spanish families. The data were analyzed by a variance-component linkage method. A strong linkage signal was found on the long arm of Chromosome 13, near the DNA marker D13S156, where the structural gene encoding for TAFI is located. In addition, other new linkage signals were detected on chromosome regions 5p and 7q. More importantly, we performed another multipoint linkage analysis of functional TAFI conditioned on TAFI antigen levels. We detected a strong linkage signal on Chromosome 19 (LOD = 3.0, P = 0.0001) suggesting a novel QTL in this region involved in the specific functional activity of TAFI, regardless of the TAFI antigen levels. One notable aspect of this study is the identification of new QTLs that reveal a clearer picture of the genetic determinants responsible for variation in TAFI levels. Another is the replication of the linkage signal of the CPB2 gene, which confirms an important genetic determinant for TAFI antigen levels. These results strongly suggest an oligogenic mode of inheritance for TAFI, in which CPB2 gene accounts for a proportion of the variation of the phenotype together with other unknown genes that may represent potential risk factors for thrombotic disease.
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Affiliation(s)
- Maria Sabater-Lleal
- Unitat d'Hemostàsia i Trombosi, Hospital de la Santa Creu i Sant Pau, C/Sant Antoni M.Claret 167. 08025, Barcelona, Spain.
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Crystal structures of TAFI elucidate the inactivation mechanism of activated TAFI: a novel mechanism for enzyme autoregulation. Blood 2008; 112:2803-9. [PMID: 18559974 DOI: 10.1182/blood-2008-03-146001] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thrombin-activatable fibrinolysis inhibitor (TAFI) is a pro-metallocarboxypeptidase that can be proteolytically activated (TAFIa). TAFIa is unique among carboxypeptidases in that it spontaneously inactivates with a short half-life, a property that is crucial for its role in controlling blood clot lysis. We studied the intrinsic instability of TAFIa by solving crystal structures of TAFI, a TAFI inhibitor (GEMSA) complex and a quadruple TAFI mutant (70-fold more stable active enzyme). The crystal structures show that TAFIa stability is directly related to the dynamics of a 55-residue segment (residues 296-350) that includes residues of the active site wall. Dynamics of this flap are markedly reduced by the inhibitor GEMSA, a known stabilizer of TAFIa, and stabilizing mutations. Our data provide the structural basis for a model of TAFI auto-regulation: in zymogen TAFI the dynamic flap is stabilized by interactions with the activation peptide. Release of the activation peptide increases dynamic flap mobility and in time this leads to conformational changes that disrupt the catalytic site and expose a cryptic thrombin-cleavage site present at Arg302. This represents a novel mechanism of enzyme control that enables TAFI to regulate its activity in plasma in the absence of specific inhibitors.
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40
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Skidgel RA, Erdös EG. Structure and function of human plasma carboxypeptidase N, the anaphylatoxin inactivator. Int Immunopharmacol 2007; 7:1888-99. [PMID: 18039526 DOI: 10.1016/j.intimp.2007.07.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Accepted: 07/06/2007] [Indexed: 12/27/2022]
Abstract
Human carboxypeptidase N (CPN) was discovered in the early 1960s as a plasma enzyme that inactivates bradykinin and was identified 8 years later as the major "anaphylatoxin inactivator" of blood. CPN plays an important role in protecting the body from excessive buildup of potentially deleterious peptides that normally act as local autocrine or paracrine hormones. This review summarizes the structure, enzymatic properties and function of this important human enzyme, including insights gained by the recent elucidation of the crystal structure of the CPN catalytic subunit and structural modeling of the non-catalytic regulatory 83 kDa subunit. We also discuss its physiological role in cleaving substrates such as kinins, anaphylatoxins, creatine kinase, plasminogen receptors, hemoglobin and stromal cell-derived factor-1alpha (SDF-1alpha).
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Affiliation(s)
- Randal A Skidgel
- Department of Pharmacology, University of Illinois at Chicago College of Medicine Chicago, IL 60612, USA.
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Guimarães AHC, Laurens N, Weijers EM, Koolwijk P, van Hinsbergh VWM, Rijken DC. TAFI and pancreatic carboxypeptidase B modulate in vitro capillary tube formation by human microvascular endothelial cells. Arterioscler Thromb Vasc Biol 2007; 27:2157-62. [PMID: 17673703 DOI: 10.1161/atvbaha.107.150144] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Besides having a key role in fibrinolysis, the plasminogen system has been implicated in cell migration and angiogenesis. A common mechanism is the binding of plasminogen to carboxy-terminal lysine residues in partially degraded fibrin or on cellular surfaces. Here we examined the involvement of thrombin activatable fibrinolysis inhibitor (TAFI) and pancreatic carboxypeptidase B (CPB) in an in vitro capillary tube formation system, which is largely plasminogen-dependent. METHODS AND RESULTS Human microvascular endothelial cells (hMVECs) were seeded on a 3D plasma clot matrix and subsequently stimulated with bFGF/tumor necrosis factor (TNF)-alpha. Tube formation was analyzed and fibrin degradation products (FbDP) were determined in the medium. Supplementation of the matrix with additional TAFI or CPB produced a reduction in tube formation. Pretreatment of hMVECs with CPB before seeding resulted in a similar effect. FbDP-levels indicated a concomitant reduction in matrix proteolysis. A TAFIa inhibitor increased tube formation and FbDP release into the medium. In separate assays, CPB impaired the migration of hMVECs in a dose-dependent manner, whereas proliferation and adhesion remained unaffected. CONCLUSIONS Overall, these results demonstrate that TAFI and CPB in these systems modulate the plasminogen system both in the matrix and on the cell surface, thus leading to the inhibition of endothelial cell movement and tube formation.
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Affiliation(s)
- Ana H C Guimarães
- Laboratory for Physiology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
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Vucelić D, Pesko P, Stojakov D, Sabljak P, Bjelović M, Dunjić M, Ebrahimi K, Nenadić B, Velicković D, Spica B. [Systemic hemostatic drugs]. ACTA CHIRURGICA IUGOSLAVICA 2007; 54:177-95. [PMID: 17633882 DOI: 10.2298/aci0701177v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Understanding the haemostatic changes is crucial in developing strategies for the management of haemorrhage syndroma. In recent years, the revised model of coagulation ("cell based" model) provided a much more authentic description of the coagulation process. Pharmacological intervention, especially desmopresin, antifibrinolytics (synthetics and nature) and increasingly recombinant activated factor VII are being used in prevention and therapeutically to control bleeding of variety etiologies. Skillfull surgery combined with blood saving methods and careful management of blood coagulation will all help in sucessfull haemorrhage prevention and treatment, and reduce unnecessary blood loss and transfusion requirements and its attendant risks. Among the all avalaible tests, the use of thromboelastography has allowed for more detailed dynamic assessment of the various steps of hemostasis.
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Affiliation(s)
- D Vucelić
- Klinika za digestivnu hirurgiju, Institut za bolesti digestivnog sistema, KCS, Beograd
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Agin A, Jeandidier N, Gasser F, Grucker D, Sapin R. Glargine blood biotransformation: in vitro appraisal with human insulin immunoassay. DIABETES & METABOLISM 2007; 33:205-12. [PMID: 17360218 DOI: 10.1016/j.diabet.2006.12.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Accepted: 12/18/2006] [Indexed: 11/22/2022]
Abstract
AIM Glargine, a long-acting insulin analogue, is metabolized in the bloodstream and in subcutaneous tissue. Glargine metabolism and its implications for diabetes therapy remain poorly understood. The aim of our study was to assess in vitro the glargine blood biotransformation and its inter-individual variability. METHODS Formation of M1 glargine metabolite in vitro was studied with Elecsys Insulin immunoassay in pools of sera and sera from patients spiked with glargine. Elecsys Insulin assay is specific of human insulin, does not recognize glargine and its M2 metabolite but does recognize its M1 metabolite. RESULTS Glargine incubation with serum resulted in M1 metabolite formation which was detected and characterized as an enzymatic process: metabolite kinetics were dependant on temperature, substrate concentration and serum proportion. Carboxypeptidase inhibitors and chelating agents partially inhibited the activity of the enzyme(s). Glargine biotransformation was decreased when blood was collected on EDTA tubes. After 30 min incubation of glargine (100 mU/l) in 69 sera at 37 degrees C, percentage of glargine converted into M1 ranged from 46% to 98% (mean 72%; S.D. 11%). CONCLUSION Glargine blood biotransformation is an enzymatic process probably involving serum carboxypeptidase(s). Metabolite formation is rapid and non negligible. Inter-individual variability of glargine biotransformation is noteworthy and should be confronted to M1 metabolite bioactivity which has not been fully documented yet.
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Affiliation(s)
- A Agin
- Centre national de la recherche scientifique, UMR 7004, institut de physique biologique, faculté de médecine, université Louis-Pasteur, 67091 Strasbourg, France.
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Islam I, Bryant J, May K, Mohan R, Yuan S, Kent L, Morser J, Zhao L, Vergona R, White K, Adler M, Whitlow M, Buckman BO. 3-Mercaptopropionic acids as efficacious inhibitors of activated thrombin activatable fibrinolysis inhibitor (TAFIa). Bioorg Med Chem Lett 2006; 17:1349-54. [PMID: 17189688 DOI: 10.1016/j.bmcl.2006.11.078] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 11/27/2006] [Accepted: 11/30/2006] [Indexed: 11/17/2022]
Abstract
A novel series of cyclic potent, selective, small molecule, thiol-based inhibitors of activated thrombin activatable fibrinolysis inhibitor (TAFIa) and the crystal structures of TAFIa inhibitors bound to porcine pancreatic carboxypeptidase B are described. Three series of cyclic arginine and lysine mimetic inhibitors vary significantly in their selectivity against other human basic carboxypeptidases, carboxypeptidase N and carboxypeptidase B. (-)2a displays TAFIa IC50 = 3 nM and 600-fold selectivity against CPN. Inhibition of TAFIa with (rac)2a resulted in dose dependent acceleration of human plasma clot lysis in vitro and was efficacious as an adjunct to tPA in an in vivo rabbit jugular vein thrombolysis model.
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Affiliation(s)
- Imadul Islam
- Department of Medicinal Chemistry, 2600 Hilltop Drive, Richmond, CA 94804, USA
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Boffa MB, Koschinsky ML. Curiouser and curiouser: recent advances in measurement of thrombin-activatable fibrinolysis inhibitor (TAFI) and in understanding its molecular genetics, gene regulation, and biological roles. Clin Biochem 2006; 40:431-42. [PMID: 17331488 DOI: 10.1016/j.clinbiochem.2006.10.020] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Accepted: 10/29/2006] [Indexed: 10/23/2022]
Abstract
The thrombin-activatable fibrinolysis inhibitor (TAFI) pathway defines a novel molecular connection between blood coagulation and both fibrinolysis and inflammation. TAFI is a plasma zymogen that can be activated by thrombin, the thrombin-thrombomodulin complex, or plasmin. The activated form of TAFI (TAFIa) attenuates fibrinolysis by removing the carboxyl-terminal lysine residues from partially degraded fibrin that mediate positive feedback in the fibrinolytic cascade. A role for TAFIa in modulating inflammation is suggested by the ability of this enzyme to down-regulate pericellular plasminogen activation and to inactivate the inflammatory peptides bradykinin and the anaphylatoxins C3a and C5a. The focus of this review is on recent advances in the clinical measurement of the TAFI pathway in human subjects and what this has revealed in terms of the molecular genetics of TAFI, the biological variation in plasma TAFI antigen levels, potential regulators of expression of the gene encoding TAFI, and the TAFI pathway as a risk factor for the development of vascular diseases. Although this field is in its infancy, much recent progress has been made and the available data suggest that the TAFI pathway is an intriguing new player in a variety of physiological and pathophysiological contexts.
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Affiliation(s)
- Michael B Boffa
- Department of Biochemistry, Queen's University, Kingston, Ontario, Canada K7L 3N6.
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46
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Werle M, Bernkop-Schnürch A. Strategies to improve plasma half life time of peptide and protein drugs. Amino Acids 2006; 30:351-67. [PMID: 16622600 DOI: 10.1007/s00726-005-0289-3] [Citation(s) in RCA: 469] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 12/16/2005] [Indexed: 10/24/2022]
Abstract
Due to the obvious advantages of long-acting peptide and protein drugs, strategies to prolong plasma half life time of such compounds are highly on demand. Short plasma half life times are commonly due to fast renal clearance as well as to enzymatic degradation occurring during systemic circulation. Modifications of the peptide/protein can lead to prolonged plasma half life times. By shortening the overall amino acid amount of somatostatin and replacing L: -analogue amino acids with D: -amino acids, plasma half life time of the derivate octreotide was 1.5 hours in comparison to only few minutes of somatostatin. A PEG(2,40 K) conjugate of INF-alpha-2b exhibited a 330-fold prolonged plasma half life time compared to the native protein. It was the aim of this review to provide an overview of possible strategies to prolong plasma half life time such as modification of N- and C-terminus or PEGylation as well as methods to evaluate the effectiveness of drug modifications. Furthermore, fundamental data about most important proteolytic enzymes of human blood, liver and kidney as well as their cleavage specificity and inhibitors for them are provided in order to predict enzymatic cleavage of peptide and protein drugs during systemic circulation.
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Affiliation(s)
- M Werle
- ThioMatrix GmbH, Research Center Innsbruck, Innsbruck, Austria
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Kaftan O, Balcik OS, Cipil H, Ozet G, Bavbek N, Koşar A, Dagdas S. Plasma levels of thrombin-activatable fibrinolysis inhibitor in primary and secondary thrombocytosis. Clin Appl Thromb Hemost 2006; 11:449-54. [PMID: 16244771 DOI: 10.1177/107602960501100412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
An elevated platelet count is a common finding in both hospitalized and ambulatory patients. Thrombosis and bleeding complications are more frequently observed in patients with clonal thrombocytosis than secondary thrombocytosis. The aim of this study was to investigate the behaviors of thrombin-activatable fibrinolysis inhibitor (TAFI) activity, the inhibitor of fibrinolysis, and also prothrombin time (PT), active partial thromboplastin time, and D-dimer and fibrinogen levels in 21 patients affected with clonal thrombocytemia as compared with 21 patients with reactive thrombocytosis and 21 healthy controls. In the clonal thrombocytemia group, plasma levels of TAFI activity were significantly higher than in both the reactive thrombocytosis and the control group. Plasma levels of leukocyte and platelet counts were significantly higher in the clonal thrombocytemia group than in the other two groups and also higher in the reactive thrombocytosis group than in the control group, which was also significant. Fibrinogen and D-dimer levels were higher in patients than in the control group but showed no significant difference between the clonal and secondary thrombocytosis groups. Plasma levels of PT and aPTT were higher in secondary thrombocytosis group than the clonal thrombocytosis group. The results of this study showed for the first time that TAFI activity is increased in patients with clonal thrombocytosis. These increased levels in clonal thrombocytosis can be considered a factor to explain the thrombotic tendency in myeloproliferative disorders.
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Affiliation(s)
- O Kaftan
- Fatih University Medical School Department of Internal Medicine, Ankara, Turkey
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Mao SS, Holahan MA, Bailey C, Wu G, Colussi D, Carroll SS, Cook JJ. Demonstration of enhanced endogenous fibrinolysis in thrombin activatable fibrinolysis inhibitor-deficient mice. Blood Coagul Fibrinolysis 2006; 16:407-15. [PMID: 16093731 DOI: 10.1097/01.mbc.0000181175.62437.2a] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To investigate the importance of thrombin activatable fibrinolysis inhibitor (TAFI) in the stabilization of plasma clots, we have compared fibrinolysis in TAFI-deficient (KO) and wild-type (WT) littermate mice. TAFI-deficient mice were previously generated by targeted gene disruption. The level of TAFI activity generated in plasma from WT mice in the presence of added thrombin and thrombomodulin (activatable TAFI) is twice that of plasma from TAFI heterozygous mice (HET); no activatable TAFI is detected in TAFI KO plasma. In vitro, TAFI KO plasma clots lysed faster than WT plasma clots, and HET plasma clots lysed at an intermediate rate. The rate of clot lysis for KO mice is not changed in the presence of potato carboxypeptidase inhibitor, a specific inhibitor of TAFIa, whereas the WT and HET clot lysis rates are increased in the presence of potato carboxypeptidase inhibitor. C-terminal lysine residues are preserved on partially degraded clots from KO mice, but are absent from partially degraded WT clots. In vivo, in a batroxobin-induced pulmonary embolism model, KO mice displayed a lower retention of fibrin in the lungs than did WT mice. These results are the first demonstration of enhanced endogenous fibrinolysis in an in vivo model without the addition of exogenous thrombolytic.
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Affiliation(s)
- Shi-Shan Mao
- Department of Biological Chemistry, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
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Bouma BN, Mosnier LO. Thrombin activatable fibrinolysis inhibitor (TAFI)--how does thrombin regulate fibrinolysis? Ann Med 2006; 38:378-88. [PMID: 17008302 DOI: 10.1080/07853890600852898] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
The thrombin-catalysed conversion of plasma fibrinogen into fibrin and the development of an insoluble fibrin clot are the final steps of the coagulation cascade during haemostasis. A delicate balance between coagulation and fibrinolysis determines the stability of the fibrin clot. Thrombin plays a central role in this process, it not only forms the clot but it is also involved in stabilizing the clot by activating thrombin activatable fibrinolysis inhibitor (TAFI). Activated TAFI protects the fibrin clot against lysis. Here we will discuss the mechanisms for regulation of fibrinolysis by thrombin. The role of the coagulation system for the generation of thrombin and for the activation of TAFI implies that defects in thrombin generation will directly affect the protection of clots against lysis. Thus, defects in activation of TAFI might contribute to the severity of bleeding disorders. Vice versa an increased activation of TAFI due to an increased rate of thrombin generation might lead to thrombotic disorders. Specific inhibitors of activated TAFI or inhibitors that interfere with the generation of thrombin might provide novel therapeutic strategies for thrombolytic therapy. Besides having a role in the regulation of fibrinolysis, TAFI may also have an important function in the regulation of inflammation, wound healing and blood pressure.
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Affiliation(s)
- Bonno N Bouma
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA.
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Ceresa E, Brouwers E, Peeters M, Jern C, Declerck PJ, Gils A. Development of ELISAs measuring the extent of TAFI activation. Arterioscler Thromb Vasc Biol 2005; 26:423-8. [PMID: 16339503 DOI: 10.1161/01.atv.0000199246.08616.98] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To date, quantitation of TAFI antigen levels has been mainly focused on "total" antigen levels and has been shown to yield ambiguous results because of the existence of different isoforms and various degrees of activation. Our objective was to develop assays that allow measuring the extent of TAFI activation. METHODS AND RESULTS A variety of enzyme-linked immunosorbent assays (ELISAs) were evaluated for their preferential reactivity toward TAFI before and after activation, and toward the recombinantly expressed activation peptide. Three ELISAs with distinct reactivities were selected: recognizing either exclusively nonactivated TAFI, the released activation peptide, or exclusively TAFIa (activated TAFI). Evaluation of TAFI activation during clot lysis revealed that decreases of TAFI levels are associated with increases of the released activation peptide and TAFIa levels. In addition, antigenic measurement of TAFIa parallels activity measured by chromogenic assay. Analyzing plasma samples revealed that subjects with hyperlipidemia had significantly higher plasma levels of both the activation peptide (109.2 versus 95.5; P<0.001) and TAFIa (112.1 versus 103.3; P=0.03), and not of TAFI antigen (92.5 versus 87.9; P=0.07) (results in % of plasma pooled from normolipidemic subjects). CONCLUSIONS ELISAs that allow to measure the extent of TAFI activation were developed. These ELISAs constitute more sensitive markers in studies on the relationship between TAFI and cardiovascular diseases.
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Affiliation(s)
- Erik Ceresa
- Laboratory for Pharmaceutical Biology and Phytopharmacology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium
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