1
|
Constantinescu-Bercu A, Wang YA, Woollard KJ, Mangin P, Vanhoorelbeke K, Crawley JTB, Salles-Crawley II. The GPIbα intracellular tail - role in transducing VWF- and collagen/GPVI-mediated signaling. Haematologica 2022; 107:933-946. [PMID: 34134470 PMCID: PMC8968903 DOI: 10.3324/haematol.2020.278242] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Indexed: 11/09/2022] Open
Abstract
The GPIbT-VWF A1 domain interaction is essential for platelet tethering under high shear. Synergy between GPIbα and GPVI signaling machineries has been suggested previously, however its molecular mechanism remains unclear. We generated a novel GPIbα transgenic mouse (GpIbαΔsig/Δsig) by CRISPR-Cas9 technology to delete the last 24 residues of the GPIbα intracellular tail that harbors the 14-3-3 and phosphoinositide-3 kinase binding sites. GPIbαΔsig/Δsig platelets bound VWF normally under flow. However, they formed fewer filopodia on VWF/botrocetin in the presence of a oIIbI3 blocker, demonstrating that despite normal ligand binding, VWF-dependent signaling is diminished. Activation of GpIbαΔsig/Δsig platelets with ADP and thrombin was normal, but GpIbαΔsig/Δsig platelets stimulated with collagen-related-peptide (CRP) exhibited markedly decreased P-selectin exposure and eIIbI3 activation, suggesting a role for the GpIbaaintracellular tail in GPVI-mediated signaling. Consistent with this, while haemostasis was normal in GPIbαΔsig/Δsig mice, diminished tyrosine-phosphorylation, (particularly pSYK) was detected in CRP-stimulated GpIbαΔsig/Δsig platelets as well as reduced platelet spreading on CRP. Platelet responses to rhodocytin were also affected in GpIbαΔsig/Δsig platelets but to a lesser extent than those with CRP. GpIbαΔsig/Δsig platelets formed smaller aggregates than wild-type platelets on collagen-coated microchannels at low, medium and high shear. In response to both VWF and collagen binding, flow assays performed with plasma-free blood or in the presence of bIIbI3- or GPVI-blockers suggested reduced bIIbI3 activation contributes to the phenotype of the GpIbαΔsig/Δsig platelets. Together, these results reveal a new role for the intracellular tail of GPIbiiin transducing both VWF-GPIbGGand collagen-GPVI signaling events in platelets.
Collapse
Affiliation(s)
| | - Yuxiao A Wang
- Centre for Haematology, Department of Immunology and Inflammation, Imperial College London, London, UK
| | - Kevin J Woollard
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, UK
| | - Pierre Mangin
- Université de Strasbourg, INSERM, EFS Grand-Est, BPPS UMR-S 1255, FMTS, Strasbourg, France
| | | | - James T B Crawley
- Centre for Haematology, Department of Immunology and Inflammation, Imperial College London, London, UK
| | - Isabelle I Salles-Crawley
- Centre for Haematology, Department of Immunology and Inflammation, Imperial College London, London, UK.
| |
Collapse
|
2
|
Braun A, Anders HJ, Gudermann T, Mammadova-Bach E. Platelet-Cancer Interplay: Molecular Mechanisms and New Therapeutic Avenues. Front Oncol 2021; 11:665534. [PMID: 34322381 PMCID: PMC8311658 DOI: 10.3389/fonc.2021.665534] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 06/17/2021] [Indexed: 12/18/2022] Open
Abstract
Although platelets are critically involved in thrombosis and hemostasis, experimental and clinical evidence indicate that platelets promote tumor progression and metastasis through a wide range of physical and functional interactions between platelets and cancer cells. Thrombotic and thromboembolic events are frequent complications in patients with solid tumors. Hence, cancer modulates platelet function by directly inducing platelet-tumor aggregates and triggering platelet granule release and altering platelet turnover. Also, platelets enhance tumor cell dissemination by activating endothelial cell function and recruiting immune cells to primary and metastatic tumor sites. In this review, we summarize current knowledge on the complex interactions between platelets and tumor cells and the host microenvironment. We also critically discuss the potential of anti-platelet agents for cancer prevention and treatment.
Collapse
Affiliation(s)
- Attila Braun
- Walther-Straub-Institute for Pharmacology and Toxicology, Ludwig-Maximilian-University, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Hans-Joachim Anders
- Division of Nephrology, Department of Medicine IV, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Thomas Gudermann
- Walther-Straub-Institute for Pharmacology and Toxicology, Ludwig-Maximilian-University, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Elmina Mammadova-Bach
- Walther-Straub-Institute for Pharmacology and Toxicology, Ludwig-Maximilian-University, Member of the German Center for Lung Research (DZL), Munich, Germany.,Division of Nephrology, Department of Medicine IV, Ludwig-Maximilians-University Hospital, Munich, Germany
| |
Collapse
|
3
|
Zhang X, Li Y, Wang N, Zhang C, Zhang D, Li Q. Effects of permanent cardiac pacemaker implantation on vascular endothelial function, blood coagulation and cardiac function in patients with bradycardia. Exp Ther Med 2018; 16:4717-4721. [PMID: 30542426 PMCID: PMC6257567 DOI: 10.3892/etm.2018.6808] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 09/24/2018] [Indexed: 11/08/2022] Open
Abstract
Changes in vascular endothelial function, blood coagulation and cardiac function indexes after the implantation of a permanent cardiac pacemaker in patients with bradycardia were investigated. A total of 53 healthy people and 117 patients with bradycardia in Jining First People's Hospital from January 2015 to August 2017 were selected. Factor VIII: coagulation (FVIII:C), von Willebr and factor (vWF), antithrombin activity (AT:A), D-dimmer (D-D), thrombomodulin (TM), tissue factor (TF), left ventricular ejection fraction (LVEF) and left ventricular end-systolic volume (LVESV) in the non-pacemaker group and the pacemaker group were significantly different from those in the control group (P<0.05), in which FVIII:C, vWF, D-D, TM, TF and LVESV were significantly higher than those in the control group, while LVEFs were significantly lower than that in the control group. After the implantation of a pacemaker, the FVIII:C, vWF, fibrinogen (FIB), D-D, TF and LVESV in patients were significantly higher than those before implantation (P<0.05), while the LVEF was significantly lower than that before implantation (P<0.05). In addition, in different pacemaker groups, there were no significant differences in blood coagulation and vascular endothelial indexes, but differences in cardiac function levels were obvious, in which LVEF in dual-chamber (DDD) pacemaker group was significantly higher than that in ventricular inhibited (VVI) pacemaker group, and LVESV in the former was significantly lower than that in the latter (P<0.05). Finally, here was no significant difference in the quality of life of patients implanted with different pacemakers (P>0.05), but the quality of life of patients in the DDD pacemaker group was better than that of patients in the VVI group. Therefore, implanting pacemakers in patients with bradycardia affects vascular endothelial function, blood coagulation, and cardiac function indexes in patients, and complications become less after the implantation of DDD pacemakers.
Collapse
Affiliation(s)
- Xinling Zhang
- The Heart Center, Jining First People's Hospital, Jining, Shandong 272011, P.R. China
| | - Yan Li
- The Heart Center, Jining First People's Hospital, Jining, Shandong 272011, P.R. China
| | - Nan Wang
- Department of Stomatology, Affiliated Hospital of Jining Medical University, Jining, Shandong 272011, P.R. China
| | - Chunxiang Zhang
- The Heart Center, Jining First People's Hospital, Jining, Shandong 272011, P.R. China
| | - Debing Zhang
- The Heart Center, Jining First People's Hospital, Jining, Shandong 272011, P.R. China
| | - Qiang Li
- The Heart Center, Jining First People's Hospital, Jining, Shandong 272011, P.R. China
| |
Collapse
|
4
|
The potential applications of mushrooms against some facets of atherosclerosis: A review. Food Res Int 2018; 105:517-536. [DOI: 10.1016/j.foodres.2017.11.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 11/08/2017] [Accepted: 11/19/2017] [Indexed: 12/16/2022]
|
5
|
Swieringa F, Kuijpers MJE, Lamers MME, van der Meijden PEJ, Heemskerk JWM. Rate-limiting roles of the tenase complex of factors VIII and IX in platelet procoagulant activity and formation of platelet-fibrin thrombi under flow. Haematologica 2015; 100:748-56. [PMID: 25769543 DOI: 10.3324/haematol.2014.116863] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 03/10/2015] [Indexed: 11/09/2022] Open
Abstract
The importance of factor Xa generation in thrombus formation has not been studied extensively so far. Here, we used mice deficient in either factor VIII or factor IX to determine the role of platelet-stimulated tenase activity in the formation of platelet-fibrin thrombi on collagen. With tissue factor present, deficiency in factor VIII or IX markedly suppressed thrombus growth, fibrin formation and platelet procoagulant activity (phosphatidylserine exposure). In either case, residual fibrin formation was eliminated in the absence of tissue factor. Effects of factor deficiencies were antagonized by supplementation of the missing coagulation factor. In wild-type thrombi generated under flow, phosphatidylserine-exposing platelets bound (activated) factor IX and factor X, whereas factor VIII preferentially co-localized at sites of von Willebrand factor binding. Furthermore, proteolytic activity of the generated activated factor X and thrombin was confined to the sites of phosphatidylserine exposure. With blood from a hemophilia A or B patient, the formation of platelet-fibrin thrombi was greatly delayed and reduced, even in the presence of high concentrations of tissue factor. A direct activated factor X inhibitor, rivaroxaban, added to human blood, suppressed both thrombin and fibrin formation. Together, these data point to a potent enforcement loop in thrombus formation due to factor X activation, subsequent thrombin and fibrin generation, causing activated factor X-mediated stimulation of platelet phosphatidylserine exposure. This implies that the factor VIII/factor IX-dependent stimulation of platelet procoagulant activity is a limiting factor for fibrin formation under flow conditions, even at high tissue factor concentrations.
Collapse
Affiliation(s)
- Frauke Swieringa
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands
| | - Marijke J E Kuijpers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands
| | - Moniek M E Lamers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands
| | - Paola E J van der Meijden
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands
| | - Johan W M Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands
| |
Collapse
|
6
|
de Witt SM, Verdoold R, Cosemans JM, Heemskerk JW. Insights into platelet-based control of coagulation. Thromb Res 2014; 133 Suppl 2:S139-48. [DOI: 10.1016/s0049-3848(14)50024-2] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
7
|
Van Kruchten R, Cosemans JMEM, Heemskerk JWM. Measurement of whole blood thrombus formation using parallel-plate flow chambers - a practical guide. Platelets 2012; 23:229-42. [PMID: 22502645 DOI: 10.3109/09537104.2011.630848] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Custom-made and commercial parallel-plate flow chambers are widely used for studies of platelet activation and thrombus formation in whole blood at defined shear rates. When used in a reproducible way, such flow chamber devices give valuable information on the thrombogenic potential of human, mouse, or rat blood. This article aims to provide a practical guide for the use of parallel-plate flow chambers in combination with routine microscopic imaging techniques. The following methodological aspects are addressed: preparation of surface coatings, calculation of blood flow and shear rate, control of pre-analytical variables, protocols for routine performing of flow chamber tests with non-coagulating or coagulating blood, and procedures for real-time and end-point analysis of thrombus formation. Frequently encountered experimental problems and artifacts are discussed, as well as possibilities for using flow chamber devices as a diagnostic tool to test antithrombotic medication.
Collapse
Affiliation(s)
- Roger Van Kruchten
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | | | | |
Collapse
|
8
|
Xu Z, Christley S, Lioi J, Kim O, Harvey C, Sun W, Rosen ED, Alber M. Multiscale model of fibrin accumulation on the blood clot surface and platelet dynamics. Methods Cell Biol 2012; 110:367-88. [PMID: 22482956 DOI: 10.1016/b978-0-12-388403-9.00014-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A multiscale computational model of thrombus (blood clot) development is extended by incorporating a submodel describing formation of fibrin network through "fibrin elements" representing regions occupied by polymerized fibrin. Simulations demonstrate that fibrin accumulates on the surface of the thrombus and that fibrin network limits growth by reducing thrombin concentrations on the thrombus surface and decreasing adhesivity of resting platelets in blood near thrombus surface. These results suggest that fibrin accumulation may not only increase the structural integrity of the thrombus but also considerably contribute toward limiting its growth. Also, a fast Graphics Processing Unit implementation is described for a multiscale computational model of the platelet-blood flow interaction.
Collapse
Affiliation(s)
- Zhiliang Xu
- Department of Applied and Computational Mathematics, University of Notre Dame, Notre Dame, Indiana, USA
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Li S, Wang Z, Liao Y, Zhang W, Shi Q, Yan R, Ruan C, Dai K. The glycoprotein Ibalpha-von Willebrand factor interaction induces platelet apoptosis. J Thromb Haemost 2010; 8:341-50. [PMID: 19840363 DOI: 10.1111/j.1538-7836.2009.03653.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
BACKGROUND The interaction of glycoprotein (GP) Ibalpha with von Willebrand factor (VWF) initiates platelet adhesion, and simultaneously triggers intracellular signaling cascades leading to platelet aggregation and thrombus formation. Some of the signaling events are similar to those occurring during apoptosis, however, it is still unclear whether platelet apoptosis is induced by the GPIbalpha-VWF interaction. OBJECTIVES To investigate whether the GPIbalpha-VWF interaction induces platelet apoptosis and the role of 14-3-3zeta in apoptotic signaling. METHODS Apoptotic events were assessed in platelets or Chinese hamster ovary (CHO) cells expressing wild-type (1b9) or mutant GPIb-IX interacting with VWF by flow cytometry or western blotting. RESULTS Ristocetin-induced GPIbalpha-VWF interaction elicited apoptotic events in platelets, including phosphatidylserine exposure, elevations of Bax and Bak, gelsolin cleavage, and depolarization of mitochondrial inner transmembrane potential. Apoptotic events were also elicited in platelets exposed to pathologic shear stresses in the presence of VWF; however, the shear-induced apoptosis was eliminated by the anti-GPIbalpha antibody AK2. Furthermore, apoptotic events occurred in 1b9 cells stimulated with VWF and ristocetin, but were significantly diminished in two CHO cell lines expressing mutant GPIb-IX with GPIbalpha truncated at residue 551 or a serine-to-alanine mutation at the 14-3-3zeta-binding site in GPIbalpha. CONCLUSIONS This study demonstrates that the GPIbalpha-VWF interaction induces apoptotic events in platelets, and that the association of 14-3-3zeta with the cytoplasmic domain of GPIbalpha is essential for apoptotic signaling. This finding may suggest a novel mechanism for platelet clearance or some thrombocytopenic diseases.
Collapse
Affiliation(s)
- S Li
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Elvers M, Stegner D, Hagedorn I, Kleinschnitz C, Braun A, Kuijpers MEJ, Boesl M, Chen Q, Heemskerk JWM, Stoll G, Frohman MA, Nieswandt B. Impaired alpha(IIb)beta(3) integrin activation and shear-dependent thrombus formation in mice lacking phospholipase D1. Sci Signal 2010; 3:ra1. [PMID: 20051593 DOI: 10.1126/scisignal.2000551] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Platelet aggregation is essential for hemostasis but can also cause myocardial infarction and stroke. A key but poorly understood step in platelet activation is the shift of the principal adhesive receptor, alpha(IIb)beta(3) integrin, from a low- to high-affinity state for its ligands, a process that enables adhesion and aggregation. In response to stimulation of heterotrimeric guanosine triphosphate-binding protein or immunoreceptor tyrosine-based activation motif-coupled receptors, phospholipases cleave membrane phospholipids to generate lipid and soluble second messengers. An essential role in platelet activation has been established for phospholipase C (PLC) but not for PLD and its product phosphatidic acid. Here, we report that platelets from Pld1(-/-) mice displayed impaired alpha(IIb)beta(3) integrin activation in response to major agonists and defective glycoprotein Ib-dependent aggregate formation under high shear conditions. These defects resulted in protection from thrombosis and ischemic brain infarction without affecting tail bleeding times. These results indicate that PLD1 may be a critical regulator of platelet activity in the setting of ischemic cardiovascular and cerebrovascular events.
Collapse
Affiliation(s)
- Margitta Elvers
- University Clinic Würzburg and Rudolf Virchow Center, DFG Research Center for Experimental Biomedicine, University of Würzburg, Josef-Schneider-Strasse 2, 97080 Würzburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Arthur JF, Shen Y, Kahn ML, Berndt MC, Andrews RK, Gardiner EE. Ligand Binding Rapidly Induces Disulfide-dependent Dimerization of Glycoprotein VI on the Platelet Plasma Membrane. J Biol Chem 2007; 282:30434-41. [PMID: 17690106 DOI: 10.1074/jbc.m701330200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thrombus formation in hemostasis or thrombotic disease is initiated by adhesion of circulating platelets to damaged blood vessel walls. Exposed subendothelial collagen interacting with platelet glycoprotein (GP) VI leads to platelet activation and integrin alpha(IIb)beta(3)-mediated aggregation. We previously showed that ligand binding to GPVI also induces metalloproteinase-dependent shedding, generating an approximately 55-kDa soluble ectodomain fragment and an approximately 10-kDa membrane-associated remnant. Here, treatment of platelets with collagen or the GPVI-targeting rattlesnake toxin convulxin also induces rapid (10-30 s) formation of a high molecular weight GPVI complex (GPVIc) under nonreducing conditions, as detected by immunoblotting with anti-GPVI antibodies. The appearance of an approximately 20-kDa remnant detectable using a polyclonal antibody against the GPVI cytoplasmic tail under nonreducing, but not reducing, conditions after ectodomain shedding and nonreduced/reduced two-dimensional SDS-polyacrylamide gel analysis of biotinylated platelets confirmed that that GPVIc was a homodimer. Formation of disulfide-linked GPVIc was prolonged in the presence of metalloproteinase inhibitor GM6001 and was independent of GPVI signaling because it was unaffected by inhibitors of Src kinases, Syk, or phosphoinositide 3-kinase. To identify the thiol involved in disulfide bond formation, wild-type or mutant GPVI, where two available sulfhydryls (Cys-274 and Cys-338) were individually mutated to serine, was expressed in rat basophilic leukemia cells. Dimerization of wild-type and C274S GPVI, but not the C338S mutant, was observed after treating cells with convulxin. We conclude that (i) a subpopulation of GPVI forms a constitutive dimer on the platelet surface, facilitating rapid disulfide cross-linking, (ii) convulxin or other GPVI agonists induce disulfide-linked GPVI dimerization independent of GPVI signaling, and (iii) the penultimate residue of the GPVI cytoplasmic tail, Cys-338, mediates disulfide-dependent dimer formation.
Collapse
Affiliation(s)
- Jane F Arthur
- Department of Immunology, Monash University, Melbourne 3004, Australia
| | | | | | | | | | | |
Collapse
|
12
|
White TC, Berny MA, Robinson DK, Yin H, DeGrado WF, Hanson SR, McCarty OJT. The leech product saratin is a potent inhibitor of platelet integrin α2β1 and von Willebrand factor binding to collagen. FEBS J 2007; 274:1481-91. [PMID: 17489103 DOI: 10.1111/j.1742-4658.2007.05689.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Subendothelial collagen plays an important role, via both direct and indirect mechanisms, in the initiation of thrombus formation at sites of vascular injury. Collagen binds plasma von Willebrand factor, which mediates platelet recruitment to collagen under high shear. Subsequently, the direct binding of the platelet receptors glycoprotein VI and alpha2beta1 to collagen is critical for platelet activation and stable adhesion. Leeches, have evolved a number of inhibitors directed towards platelet-collagen interactions so as to prevent hemostasis in the host during hematophagy. In this article, we describe the molecular mechanisms underlying the ability of the leech product saratin to inhibit platelet binding to collagen. In the presence of inhibitors of ADP and thromboxane A2, both saratin and 6F1, a blocking alpha2beta1 mAb, abrogated platelet adhesion to fibrillar and soluble collagen. Additionally, saratin eliminated alpha2beta1-dependent platelet adhesion to soluble collagen in the presence of an Src kinase inhibitor. Moreover, saratin prevented platelet-rich plasma adhesion to fibrillar collagen, a process dependent upon both alpha2beta1 and von Willebrand factor binding to collagen. Furthermore, saratin specifically inhibited the binding of the alpha2 integrin subunit I domain to collagen, and prevented platelet adhesion to collagen under flow to the same extent as observed in the presence of a combination of mAbs to glycoprotein Ib and alpha2beta1. These results demonstrate that saratin interferes with integrin alpha2beta1 binding to collagen in addition to inhibiting von Willebrand factor-collagen binding, presumably by binding to an overlapping epitope on collagen. This has significant implications for the use of saratin as a tool to inhibit platelet-collagen interactions.
Collapse
Affiliation(s)
- Tara C White
- Department of Biomedical Engineering, Oregon Health & Science University, 13B-CHH, 3303 SW Bond Avenue, Portland, OR 97239, USA
| | | | | | | | | | | | | |
Collapse
|
13
|
Munnix ICA, Strehl A, Kuijpers MJE, Auger JM, van der Meijden PEJ, van Zandvoort MAM, oude Egbrink MGA, Nieswandt B, Heemskerk JWM. The Glycoprotein VI-Phospholipase Cγ2 Signaling Pathway Controls Thrombus Formation Induced by Collagen and Tissue Factor In Vitro and In Vivo. Arterioscler Thromb Vasc Biol 2005; 25:2673-8. [PMID: 16254207 DOI: 10.1161/01.atv.0000193568.71980.4a] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Both collagen and tissue factor can be initiating factors in thrombus formation. We investigated the signaling pathway of collagen-induced platelet activation in interaction with tissue factor–triggered coagulation during the thrombus-forming process.
Methods and Results—
In murine blood flowing over collagen, platelet exposure of phosphatidylserine and procoagulant activity, but not adhesion, completely relied on each of the following signaling modules: glycoprotein VI (GPVI), FcR γ-chain, Src kinases, adaptor protein LAT, and phospholipase Cγ2 (PLCγ2). On flow in the presence of tissue factor, these signaling components were essential for platelet aggregation and greatly enhanced fibrin clot formation. Collagen-stimulated thrombin generation relied on the presence and activity of GPVI, FcR γ-chain, Src kinase, LAT, and PLCγ2. The physiological importance of this GPVI pathway was shown in a FeCl
3
-induced in vivo murine thrombosis model. In both venules and arterioles, signaling through GPVI, FcR γ-chain, and Src kinases enhanced the formation of phosphatidylserine-exposing and fibrin-rich thrombi.
Conclusions—
The GPVI-PLCγ2 activation pathway regulates collagen-dependent coagulation in venous and arterial thrombus formation.
Collapse
Affiliation(s)
- Imke C A Munnix
- Department of Biochemistry, CARIM, Maastricht University, Maastricht, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Abstract
Coated-platelets, formerly known as COAT-platelets, represent a subpopulation of cells observed after dual agonist stimulation of platelets with collagen and thrombin. This class of platelets retains on its surface high levels of several procoagulant proteins, including fibrinogen, von Willebrand factor, fibronectin, factor V and thrombospondin. Coated-platelets also express surface phosphatidylserine and strongly support prothrombinase activity. Retention of alpha-granule proteins on the surface of coated-platelets involves an unexpected derivatization of these proteins with serotonin and an interaction of serotonin-conjugated proteins with serotonin binding sites on fibrinogen and thrombospondin. This review will also detail experimental systems where coated-platelets are generated as a result of other agonist(s). Finally, the putative physiological consequences of coated-platelet formation will be discussed.
Collapse
Affiliation(s)
- G L Dale
- W.K. Warren Medical Research Institute, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| |
Collapse
|
15
|
Heemskerk JWM, Kuijpers MJE, Munnix ICA, Siljander PRM. Platelet Collagen Receptors and Coagulation. A Characteristic Platelet Response as Possible Target for Antithrombotic Treatment. Trends Cardiovasc Med 2005; 15:86-92. [PMID: 16039967 DOI: 10.1016/j.tcm.2005.03.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Collagen is a unique agonist of platelets, because it acts as an immobilized ligand that only causes platelet activation after stable adhesion. This review addresses the present understanding of how platelet interaction with collagen supports the process of thrombin generation and coagulation. Only some of the collagen-adhered platelets, that is, those showing profound changes in shape and shedding microparticles (resembling apoptotic cells), appear to contribute to the procoagulant activity of platelets. The main signaling receptor for collagen, glycoprotein VI, plays a key role in the platelet procoagulant response during thrombus formation; this is a reason why new anti-glycoprotein-VI antibodies are promising antithrombotic tools.
Collapse
Affiliation(s)
- Johan W M Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), University of Maastricht, The Netherlands.
| | | | | | | |
Collapse
|
16
|
Remenyi G, Szasz R, Friese P, Dale GL. Role of Mitochondrial Permeability Transition Pore in Coated-Platelet Formation. Arterioscler Thromb Vasc Biol 2005; 25:467-71. [PMID: 15591217 DOI: 10.1161/01.atv.0000152726.49229.bf] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Coated-platelets are a subset of cells observed during costimulation of platelets with collagen and thrombin. Important characteristics of coated-platelets include retention of multiple alpha-granule proteins and expression of phosphatidylserine on the cell surface. The mitochondrial permeability transition pore (MPTP) is a key step in apoptosis and is suggested to be involved in some forms of platelet activation. The objective of this study was to examine the role of MPTP in the synthesis of coated-platelets. METHODS AND RESULTS Flow cytometric analysis of coated-platelet production was used to examine the impact of pharmacological effectors of MPTP formation. Cyclosporin A, coenzyme Q, and bongkrekic acid all inhibit MPTP formation as well as production of coated-platelets. Phenylarsine oxide and diamide, both potentiators of MPTP formation, stimulate coated-platelet synthesis. Atractyloside, another inducer of MPTP formation, does not affect the percentage of coated-platelets synthesized; however, it does increase the level of phosphatidylserine exposed on the surface of coated-platelets. CONCLUSIONS These findings indicate that MPTP formation is an integral event in the synthesis of coated-platelets. Although the exact function of the MPTP remains to be determined, these data support a growing body of evidence that apoptosis-associated events are vital components of the platelet activation process. Formation of coated-platelets involves a complex set of activation events initiated by dual agonist activation. The mitochondrial permeability transition pore (MPTP) is a key intermediate in apoptosis and has been suggested to impact platelet activation. This report demonstrates that MPTP formation is essential to production of coated-platelets.
Collapse
Affiliation(s)
- Gyula Remenyi
- W.K. Warren Medical Research Institute, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA
| | | | | | | |
Collapse
|