351
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Hess K, Grant PJ. Inflammation and thrombosis in diabetes. Thromb Haemost 2011; 105 Suppl 1:S43-54. [PMID: 21479339 DOI: 10.1160/ths10-11-0739] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Accepted: 02/14/2011] [Indexed: 02/06/2023]
Abstract
Patients with diabetes mellitus are at increased risk of cardiovascular morbidity and mortality. Atherothrombosis, defined as atherosclerotic lesion disruption with superimposed thrombus formation, is the most common cause of death among these patients. Following plaque rupture, adherence of platelets is followed by local activation of coagulation, the formation of a cross-linked fibrin clot and the development of an occlusive platelet rich fibrin mesh. Patients with diabetes exhibit a thrombotic risk clustering which is composed of hyper-reactive platelets, up regulation of pro-thrombotic markers and suppression of fibrinolysis. These changes are mainly mediated by the presence of insulin resistance and dysglycaemia and an increased inflammatory state which directly affects platelet function, coagulation factors and clot structure. This prothrombotic state is related to increased cardiovascular risk and may account for the reduced response to antithrombotic therapeutic approaches, underpinning the need for adequate antithrombotic therapy in patients with diabetes to reduce their cardiovascular mortality.
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Affiliation(s)
- Katharina Hess
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Genetics, Health and Therapeutics, LIGHT Laboratories, Clarendon Way, University of Leeds, Leeds, UK
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352
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Reid HM, Wikström K, Kavanagh DJ, Mulvaney EP, Kinsella BT. Interaction of angio-associated migratory cell protein with the TPα and TPβ isoforms of the human thromboxane A2 receptor. Cell Signal 2011; 23:700-17. [DOI: 10.1016/j.cellsig.2010.12.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 12/08/2010] [Accepted: 12/12/2010] [Indexed: 11/16/2022]
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353
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Oral antiplatelet therapy for atherothrombotic disease: current evidence and new directions. Am Heart J 2011; 161:450-61. [PMID: 21392598 DOI: 10.1016/j.ahj.2010.10.043] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 10/04/2010] [Indexed: 11/22/2022]
Abstract
Despite the proven efficacy of dual antiplatelet therapy with aspirin and one of the first-generation P2Y(12) antagonists (clopidogrel, prasugrel) in patients with atherothrombotic disease, residual ischemic risk remains substantial, and bleeding rates are increased. Incomplete protection against ischemic events can be attributed to the fact that these therapies each target a single platelet activation pathway, allowing continued platelet activation via other pathways, including the protease-activated receptor-1 (PAR-1) pathway stimulated by thrombin. Increased bleeding with dual antiplatelet therapy can be attributed to blockade of the thromboxane A(2) (by aspirin) and adenosine diphosphate (by P2Y(12) antagonist) platelet activation pathways that are essential to hemostasis. The second-generation P2Y(12) inhibitor ticagrelor plus aspirin demonstrated superior ischemic outcomes, including reduction in total mortality, versus clopidogrel plus aspirin, but event rates remain high, and major bleeding not related to coronary artery bypass grafting is increased. The novel P2Y(12) antagonist elinogrel, available in intravenous and oral formulations, may have a more favorable benefit-to-risk profile than existing agents in this class because of reversible and competitive binding to the P2Y(12) receptor. Inhibition of PAR-1 is an attractive, novel approach in antiplatelet therapy because it may provide incremental ischemic protection without increasing bleeding. The PAR-1 antagonist vorapaxar (SCH 530348) has been associated with favorable efficacy and safety in phase 2 trials. Two phase 3 trials are evaluating the efficacy and safety of vorapaxar in patients presenting with non-ST-segment elevation acute coronary syndromes and in patients with documented atherothrombotic disease.
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354
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Turner EC, Kavanagh DJ, Mulvaney EP, McLean C, Wikström K, Reid HM, Kinsella BT. Identification of an interaction between the TPalpha and TPbeta isoforms of the human thromboxane A2 receptor with protein kinase C-related kinase (PRK) 1: implications for prostate cancer. J Biol Chem 2011; 286:15440-57. [PMID: 21357687 DOI: 10.1074/jbc.m110.181180] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In humans, thromboxane (TX) A(2) signals through the TPα and TPβ isoforms of the TXA(2) receptor or TP. Here, the RhoA effector protein kinase C-related kinase (PRK) 1 was identified as an interactant of both TPα and ΤPβ involving common and unique sequences within their respective C-terminal (C)-tail domains and the kinase domain of PRK1 (PRK1(640-942)). Although the interaction with PRK1 is constitutive, agonist activation of TPα/TPβ did not regulate the complex per se but enhanced PRK1 activation leading to phosphorylation of its general substrate histone H1 in vitro. Altered PRK1 and TP expression and signaling are increasingly implicated in certain neoplasms, particularly in androgen-associated prostate carcinomas. Agonist activation of TPα/TPβ led to phosphorylation of histone H3 at Thr(11) (H3 Thr(11)), a previously recognized specific marker of androgen-induced chromatin remodeling, in the prostate LNCaP and PC-3 cell lines but not in primary vascular smooth muscle or endothelial cells. Moreover, this effect was augmented by dihydrotestosterone in androgen-responsive LNCaP but not in nonresponsive PC-3 cells. Furthermore, PRK1 was confirmed to constitutively interact with TPα/TPβ in both LNCaP and PC-3 cells, and targeted disruption of PRK1 impaired TPα/TPβ-mediated H3 Thr(11) phosphorylation in, and cell migration of, both prostate cell types. Collectively, considering the role of TXA(2) as a potent mediator of RhoA signaling, the identification of PRK1 as a bona fide interactant of TPα/TPβ, and leading to H3 Thr(11) phosphorylation to regulate cell migration, has broad functional significance such as within the vasculature and in neoplasms in which both PRK1 and the TPs are increasingly implicated.
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Affiliation(s)
- Elizebeth C Turner
- School of Biomolecular and Biomedical Sciences, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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355
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Abstract
Although their central role is to control bleeding and to induce thrombosis, platelets are important inflammatory and immune cells as well as modulators of angiogenesis. This review focuses on the different roles of platelets in hemostasis, thrombosis, inflammation, arteriosclerosis, angiogenesis, antimicrobial host defense and hematogenous tumor metastasis. Platelets are the central regulators of hemostasis. On their surface the important thrombin burst takes place. Platelets cause atherothrombotic vascular occlusions. However, they are probably involved in early stages of arteriosclerosis, e.g. extravasation of leukocytes at sites of vascular injury, formation of foam cells and proliferation of smooth muscle cells. These processes are triggered by secretion of proinflammatory substances and growth factors as well as by platelet-cell interactions via specific adhesive axes. During infections platelets kill pathogens through secretion of antimicrobial substances and extracellular traps or nets. Platelets facilitate the revascularisation of ischemic tissue and therefore even promote tumor growth.
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Affiliation(s)
- K Jurk
- Experimentelle und Klinische Hämostaseologie, Klinik und Poliklinik für Anästhesiologie und operative Intensivmedizin, Universitätsklinikum Münster, Mendelstraße 11, 48149, Münster, Deutschland
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356
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Johnston-Cox HA, Ravid K. Adenosine and blood platelets. Purinergic Signal 2011; 7:357-65. [PMID: 21484090 DOI: 10.1007/s11302-011-9220-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 01/19/2011] [Indexed: 02/07/2023] Open
Abstract
Adenosine is an important regulatory metabolite and an inhibitor of platelet activation. Adenosine released from different cells or generated through the activity of cell-surface ectoenzymes exerts its effects through the binding of four different G-protein-coupled adenosine receptors. In platelets, binding of A(2) subtypes (A(2A) or A(2B)) leads to consequent elevation of intracellular cyclic adenosine monophosphate, an inhibitor of platelet activation. The significance of this ligand and its receptors for platelet activation is addressed in this review, including how adenosine metabolism and its A(2) subtype receptors impact the expression and activity of adenosine diphosphate receptors. The expression of A(2) adenosine receptors is induced by conditions such as oxidative stress, a hallmark of aging. The effect of adenosine receptors on platelet activation during aging is also discussed, as well as potential therapeutic applications.
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Affiliation(s)
- Hillary A Johnston-Cox
- Departments of Medicine and Biochemistry, Whitaker Cardiovascular Institute, and Evans Center for Interdisciplinary Biomedical Research, Boston University School of Medicine, CVI, 700 Albany St., Boston, MA, 02118, USA
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357
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Abstract
Traditionally viewed as major cellular components in hemostasis and thrombosis, the contribution of platelets to the progression of cancer is an emerging area of research interest. Complex interactions between tumor cells and circulating platelets play an important role in cancer growth and dissemination, and a growing body of evidence supports a role for physiologic platelet receptors and platelet agonists in cancer metastases and angiogenesis. Platelets provide a procoagulant surface facilitating amplification of cancer-related coagulation, and can be recruited to shroud tumor cells, thereby shielding them from immune responses, and facilitate cancer growth and dissemination. Experimental blockade of key platelet receptors, such as GP1b/IX/V, GPIIbIIIa and GPVI, has been shown to attenuate metastases. Platelets are also recognized as dynamic reservoirs of proangiogenic and anti-angiogenic proteins that can be manipulated pharmacologically. A bidirectional relationship between platelets and tumors is also seen, with evidence of 'tumor conditioning' of platelets. The platelet as a reporter of malignancy and a targeted delivery system for anticancer therapy has also been proposed. The development of platelet inhibitors that influence malignancy progression and clinical testing of currently available antiplatelet drugs represents a promising area of targeted cancer therapy.
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Affiliation(s)
- N M Bambace
- Division of Hematology and Oncology, Department of Medicine, University of Vermont, Burlington, VT 05401, USA
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358
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Wu CC, Wu SY, Liao CY, Teng CM, Wu YC, Kuo SC. The roles and mechanisms of PAR4 and P2Y12/phosphatidylinositol 3-kinase pathway in maintaining thrombin-induced platelet aggregation. Br J Pharmacol 2011; 161:643-58. [PMID: 20880402 DOI: 10.1111/j.1476-5381.2010.00921.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE Activation of human platelets by thrombin is mediated predominately through two proteinase-activated receptors (PARs), PAR1 and PAR4. Phosphatidylinositol 3-kinase (PI3K) inhibition leads to reversible PAR1-mediated platelet aggregation, but has no effect on the stability of platelet aggregation induced by thrombin. In the present study, the molecular mechanisms underlying this difference were investigated. EXPERIMENTAL APPROACH The functions of PI3K and PAR4 were assessed using specific inhibitors and aggregometry. The duration of platelet glycoprotein (GP) IIb/IIIa exposure was determined by flow cytometry with the antibody PAC-1. Western blotting and fluo-3 was used to evaluate the activation of Akt and protein kinase C (PKC) and intracellular Ca(2+) mobilization respectively. KEY RESULTS When PAR4 function was inhibited either by the PAR4 antagonist YD-3 [1-benzyl-3-(ethoxycarbonylphenyl)-indazole] or by receptor desensitization, the PI3K inhibitor wortmannin turned thrombin-elicited platelet aggregation from an irreversible event to a reversible event. Moreover, wortmannin plus YD-3 markedly accelerated the inactivation of GPIIb/IIIa in thrombin-stimulated platelets. The aggregation-reversing activity mainly resulted from inhibition of both PI3K-dependent PKC activation and PAR4-mediated sustained intracellular Ca(2+) rises. Blockade of ADP P2Y(12) receptor with 2-methylthioadenosine 5'-monophosphate triethylammonium salt mimicked the inhibitory effect of wortmannin on PI3K-dependent PKC activation and its ability to reverse PAR1-activating peptide-induced platelet aggregation. Co-administration of 2-methylthioadenosine 5'-monophosphate triethylammonium salt with YD-3 also decreased the stability of thrombin-induced platelet aggregation. CONCLUSIONS AND IMPLICATIONS These results suggest that PAR4 acts in parallel with the P2Y(12)/PI3K pathway to stabilize platelet aggregates, and provide new insights into the mechanisms of thrombus stabilization and potential applications for antithrombotic therapy.
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Affiliation(s)
- Chin-Chung Wu
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan
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359
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Zhang Y, Zhao Y, Lu S, Zhu M, He Y, Ruan C. A high-throughput biotin-avidin-ELISA for studying expression of platelet membrane glycoproteins and its clinical application. TOHOKU J EXP MED 2011; 222:83-8. [PMID: 20823666 DOI: 10.1620/tjem.222.83] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Platelet membrane glycoproteins (GPs) are critical for normal platelet adhesion, activation and aggregation. To define the abnormalities in surface GP expression on circulating platelets and provide a better biomarker of bleeding and thrombotic disorders, we have developed a accurate, time-saving and high-throughput biotin-avidin enzyme-linked immunosorbent assay (BA-ELISA) with the monoclonal antibodies (mAbs), 7E3 against the complex of GPIIb and GPIIIa (GPIIb/IIIa), SZ-51 against P-selectin, and SZ-2 against GPIb, respectively. The levels of P-selectin and GPIIb/IIIa were measured in patients with acute myocardial infarction (AMI), intracerebral hemorrhage (ICH), or diabetes mellitus (DM)) and healthy subjects. Inhibition of GP expression was evaluated with SZ-21, an inhibitory mAb against GPIIIa and aspirin, respectively. The sensitivity of BA-ELISA is high enough to detect platelet count as low as 3.13 x 10(9)/L in platelet-rich plasma (PRP). Both the inter-assay and intra-assay coefficient variation are less than 10%. Adenosine diphosphate (ADP)-induced or non-ADP-induced expression of P-selectin and GPIIb/IIIa was significantly higher in AMI, ICH or DM than that in controls (P < 0.01 for each). Either SZ-21 or aspirin can inhibit the ADP-induced expression of P-selectin and GPIIb/IIIa. Importantly, a high correlation was detected between BA-ELISA and flow cytometry methods. These observations indicate that BA-ELISA is a sensitive and high-throughput assay for evaluating platelet GP expression. The newly developed BA-ELISA can be popularized in community hospitals, because it does not require sophisticated equipments and reagents. This method is suitable for screening inhibitors of platelet activation and has a potential in use for diagnostic purposes.
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Affiliation(s)
- Youtao Zhang
- Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Haemostasis, Ministry of Health, Suzhou, Jiangsu, China
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360
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Schinner E, Salb K, Schlossmann J. Signaling via IRAG is essential for NO/cGMP-dependent inhibition of platelet activation. Platelets 2011; 22:217-27. [PMID: 21244222 DOI: 10.3109/09537104.2010.544151] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Platelet activation is strongly affected by nitric oxide/cyclic GMP (NO/cGMP) signaling involving cGMP-dependent protein kinase I (cGKI). Previously it was shown that interaction of the cGKI substrate IRAG with InsP(3)RI is essential for NO/cguanosine monophosphate (GMP)-dependent inhibition of platelet aggregation in vitro and in vivo. However, the role of Inositol-trisphosphate receptor associated cGMP kinase substrate (IRAG) for platelet adhesion or granule secretion was unknown. Here, we analysed the functional role of IRAG for platelet activation. Murine IRAG-deficient platelets displayed enhanced aggregability towards several agonists (collagen, thrombin and TxA2). NO- or cGMP-dependent inhibition of agonist induced ATP- or 5-HT secretion from dense granules, and P-selectin secretion from alpha granules was severely affected in IRAG-deficient platelets. Concomitantly, the effect of NO/cGMP on platelet aggregation was strongly reduced in IRAG-deficient platelets. Furthermore, GPIIb/IIIa-mediated adhesion of platelets to fibrinogen could only weakly be inhibited in IRAG-deficient mice contrary to wild-type (WT) mice. Our results suggest that signaling via IRAG is essential for NO/cGMP-dependent inhibition of platelet activation regarding granule secretion, aggregation and adhesion. This platelet disorder might cause that the bleeding time of IRAG-deficient mice was reduced.
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Affiliation(s)
- Elisabeth Schinner
- Pharmacology and Toxicology, University Regensburg, Universitätsstr. 31, 93040 Regensburg, Germany
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361
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Magallon J, Chen J, Rabbani L, Dangas G, Yang J, Bussel J, Diacovo T. Humanized mouse model of thrombosis is predictive of the clinical efficacy of antiplatelet agents. Circulation 2011; 123:319-26. [PMID: 21220740 DOI: 10.1161/circulationaha.110.951970] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND In vivo testing of novel antiplatelet agents requires informative biomarkers. By genetically modifying mouse von Willebrand factor (VWF(R1326H)), we have developed a small animal model that supports human but not mouse platelet-mediated thrombosis. Here, we evaluate the use of this biological platform as a pharmacodynamic biomarker for antithrombotic therapies. METHODS AND RESULTS The antithrombotic effects of several αIIbβ3 inhibitors were determined in VWF(R1326H) mutant mice infused with human platelets. Administration of abciximab, eptifibatide, or tirofiban at doses recommended for percutaneous coronary intervention (per 1 kg of body weight) significantly reduced human platelet-mediated thrombus formation in laser-injured arterioles by > 75% (P < 0.001). In contrast, clot size in wild-type control animals remained essentially unchanged (P > 0.05), results consistent with observed species differences in IC₅₀ values obtained by aggregometry. To further demonstrate that our biological platform is unique among standard mouse models, we evaluated the thrombogenic potential of platelets from healthy volunteers before and after clopidogrel therapy. Consistent with the antithrombotic effect of this agent, platelets postdrug administration formed smaller thrombi than cells before therapy and were less responsive to ADP-induced aggregation (P < 0.001). CONCLUSIONS The ability of αIIbβ3 and P2Y₁₂ inhibitors to limit human platelet clot formation at doses recommended by the American College of Cardiology/American Heart Association suggests that VWF(R1326H) mutant mice can serve as both a pharmacodynamic and a functional response biomarker, attributes essential for not only expediting drug development but also designing clinical studies.
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Affiliation(s)
- Jorge Magallon
- Division of Cardiology, Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA
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362
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Israels SJ, El-Ekiaby M, Quiroga T, Mezzano D. Inherited disorders of platelet function and challenges to diagnosis of mucocutaneous bleeding. Haemophilia 2011; 16 Suppl 5:152-9. [PMID: 20590875 DOI: 10.1111/j.1365-2516.2010.02314.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
SUMMARY Platelets play a pivotal role in the arrest of bleeding at sites of vascular injury. Following endothelial damage, they respond rapidly by adhesion to subendothelial matrix proteins resulting in platelet activation, spreading, aggregation, secretion and recruitment of additional platelets to form the primary haemostatic plug. This mass provides a surface for thrombin generation and fibrin mesh formation that stabilizes the clot. Careful study of patients with inherited platelet disorders and, subsequently, of informative animal models, has identified structural platelet abnormalities that have enhanced our understanding of platelet function. The investigations of rare, but severe, inherited platelet disorders have led us to the discovery of causative molecular defects. One of the most informative is the rare autosomal recessive disorder Glanzmann thrombasthenia, caused by defect or deficiency in the platelet integrin alphaIIbbeta3, resulting in absent platelet aggregation and a significant clinical bleeding diathesis. Our new challenge is to understand the mechanisms underlying more common, but less well-defined, mucocutaneous bleeding (MCB) disorders. Present diagnostic testing for platelet function disorders and von Willebrand's Disease often fails to identify the cause of bleeding in individuals with inherited MCB.
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Affiliation(s)
- S J Israels
- Department of Pediatrics & Child Health, University of Manitoba, Winnipeg, MB, Canada.
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363
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Ueno M, Kodali M, Tello-Montoliu A, Angiolillo DJ. Role of Platelets and Antiplatelet Therapy in Cardiovascular Disease. J Atheroscler Thromb 2011; 18:431-42. [DOI: 10.5551/jat.7633] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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364
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Schneider JG, Amend SH, Weilbaecher KN. Integrins and bone metastasis: integrating tumor cell and stromal cell interactions. Bone 2011; 48:54-65. [PMID: 20850578 PMCID: PMC3010439 DOI: 10.1016/j.bone.2010.09.016] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 09/04/2010] [Indexed: 01/24/2023]
Abstract
Integrins on both tumor cells and the supporting host stromal cells in bone (osteoclasts, new blood vessels, inflammatory cells, platelets and bone marrow stromal cells) play key roles in enhancing bone metastasis. Tumor cells localize to specific tissues through integrin-mediated contacts with extracellular matrix and stromal cells. Integrin expression and signaling are perturbed in cancer cells, allowing them to "escape" from cell-cell and cell-matrix tethers, invade, migrate and colonize within new tissues and matrices. Integrin signaling through αvβ3 and VLA-4 on tumor cells can promote tumor metastasis to and proliferation in the bone microenvironment. Osteoclast (OC) mediated bone resorption is a critical component of bone metastasis and can promote tumor growth in bone and αvβ3 integrins are critical to OC function and development. Tumors in the bone microenvironment can recruit new blood vessel formation, platelets, pro-tumor immune cells and bone marrow stromal cells that promote tumor growth and invasion in bone. Integrins and their ligands play critical roles in platelet aggregation (αvβ3 and αIIbβ3), hematopoietic cell mobilization (VLA-4 and osteopontin), neoangiogenesis (αvβ3, αvβ5, α6β4, and β1 integrin) and stromal function (osteopontin and VLA-4). Integrins are involved in the pathogenesis of bone metastasis at many levels and further study to define integrin dysregulation by cancer will yield new therapeutic targets for the prevention and treatment of bone metastasis.
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Affiliation(s)
- Jochen G. Schneider
- Institute for Clinical Biochemistry and Pathobiochemistry, University of Wuerzburg, Germany, and Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Luxembourg
| | - Sarah H. Amend
- Department of Medicine and Division of Oncology, Washington University, School of Medicine, St. Louis, MO, USA
| | - Katherine N. Weilbaecher
- Department of Medicine and Division of Oncology, Washington University, School of Medicine, St. Louis, MO, USA
- Corresponding author: Katherine Weilbaecher, Department of Medicine and Cell Biology and Physiology, Division of Oncology, Washington University, School of Medicine, 660 S. Euclid Ave, PO Box 8069, St. Louis, MO, 63110, USA
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365
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Abstract
Emergency department physicians, along with hospitalists and interventional cardiologists, provide first-line care for patients experiencing symptoms potentially associated with acute coronary syndromes (ACS). Because these health care providers encounter and manage patients with varying degrees of risk, a clear understanding of the modes of action, benefits, and limitations of various therapeutic options is crucial for achieving optimal outcomes in the acute-care setting. Oral antiplatelet therapy has a major role in the acute care of patients with suspected ACS due to the critical role of platelets in the pathophysiology of disease. The current standard-of-care oral antiplatelet therapy for ACS is aspirin in combination with a P2Y12 adenosine diphosphate (ADP) receptor antagonist, most commonly clopidogrel. Aspirin and P2Y12 antagonists have both demonstrated efficacy in reducing morbidity and mortality in patients with ACS, but are also associated with increased bleeding risk compared with controls. Additionally, despite dual oral antiplatelet therapy, patients remain at substantial residual risk for ischemic events due to thrombotic episodes driven by platelet activation pathways that are not inhibited by these agents, including the protease-activated receptor (PAR)-1 platelet activation pathway, stimulated by thrombin. Novel oral antiplatelet agents in advanced clinical development include a direct and more readily reversible P2Y12 antagonist, ticagrelor, as well as a new class of PAR-1 antagonists, which includes vorapaxar and atopaxar. Ticagrelor has shown a significant ischemic benefit and an increase in non-surgical bleeding over clopidogrel in the large phase 3 Platelet Inhibition and Patient Outcomes trial. Results of phase 2 trials with PAR-1 antagonists suggest that these agents may provide incremental reduction in ischemic events without a bleeding liability. This hypothesis is being evaluated in 2 large ongoing phase 3 trials with vorapaxar, including the Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome (TRA*CER) trial in patients with non-ST-segment elevation ACS.
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Affiliation(s)
- Charles V Pollack
- Department of Emergency Medicine, Pennsylvania Hospital, Philadelphia, PA 19107, USA.
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366
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Johnston-Cox HA, Yang D, Ravid K. Physiological implications of adenosine receptor-mediated platelet aggregation. J Cell Physiol 2010; 226:46-51. [PMID: 20717958 DOI: 10.1002/jcp.22379] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Adenosine is an important mediator of inhibition of platelet activation. This metabolite is released from various cells, as well as generated via activity of ecto-enzymes on the cell surface. Binding of adenosine to A(2) subtypes (A(2A) or A(2B)), G-protein coupled adenosine receptors, results in increased levels of intracellular cyclic adenosine monophosphate (cAMP), a strong inhibitor of platelet activation. The role and importance of adenosine and its receptors in platelet physiology are addressed in this review, including recently identified roles for the A(2B) adenosine receptor as a modulator of platelet activation through its newly described role in the control of expression of adenosine diphosphate (ADP) receptors.
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Affiliation(s)
- Hillary A Johnston-Cox
- Departments of Medicine and Biochemistry, Whitaker Cardiovascular Institute, Evans Center for Interdisciplinary Biomedical Research, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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367
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Abstract
Upon vascular injury, platelets are activated by adhesion to adhesive proteins, such as von Willebrand factor and collagen, or by soluble platelet agonists, such as ADP, thrombin, and thromboxane A(2). These adhesive proteins and soluble agonists induce signal transduction via their respective receptors. The various receptor-specific platelet activation signaling pathways converge into common signaling events that stimulate platelet shape change and granule secretion and ultimately induce the "inside-out" signaling process leading to activation of the ligand-binding function of integrin α(IIb)β(3). Ligand binding to integrin α(IIb)β(3) mediates platelet adhesion and aggregation and triggers "outside-in" signaling, resulting in platelet spreading, additional granule secretion, stabilization of platelet adhesion and aggregation, and clot retraction. It has become increasingly evident that agonist-induced platelet activation signals also cross talk with integrin outside-in signals to regulate platelet responses. Platelet activation involves a series of rapid positive feedback loops that greatly amplify initial activation signals and enable robust platelet recruitment and thrombus stabilization. Recent studies have provided novel insight into the molecular mechanisms of these processes.
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Affiliation(s)
- Zhenyu Li
- Department of Medicine, University of Kentucky
| | | | | | - Xiaoping Du
- Department of Pharmacology, University of Illinois at Chicago
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368
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Affiliation(s)
- M Jandrot-Perrus
- Inserm U698, hôpital Bichat, 46, rue Henri-Huchard, 75877 Paris cedex 18, France.
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369
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Platelet receptor signaling in thrombus formation. J Mol Med (Berl) 2010; 89:109-21. [DOI: 10.1007/s00109-010-0691-5] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 09/27/2010] [Accepted: 10/08/2010] [Indexed: 01/09/2023]
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370
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Thijs T, Nuyttens BP, Deckmyn H, Broos K. Platelet physiology and antiplatelet agents. Clin Chem Lab Med 2010; 48 Suppl 1:S3-13. [PMID: 21054192 DOI: 10.1515/cclm.2010.363] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Apart from the central beneficial role platelets play in hemostasis, they are also involved in atherothrombotic diseases. Here, we review the current knowledge of platelet intracellular signal transduction pathways involved in platelet adhesion, activation, amplification of the activation signal and aggregation, as well as pathways limiting platelet aggregation. A thorough understanding of these pathways allows explanation of the mechanism of action of existing antiplatelet agents, but also helps to identify targets for novel drug development.
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Affiliation(s)
- Tim Thijs
- Laboratory for Thrombosis Research, KU Leuven campus Kortrijk, Kortrijk, Belgium
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371
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Leonardi S, Tricoci P, Becker RC. Thrombin Receptor Antagonists for the Treatment of Atherothrombosis. Drugs 2010; 70:1771-83. [DOI: 10.2165/11538060-000000000-00000] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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372
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Bonaca MP, Morrow DA. SCH 530348: a novel oral thrombin receptor antagonist. Future Cardiol 2010; 5:435-42. [PMID: 19715408 DOI: 10.2217/fca.09.27] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SCH 530348, a synthetic tricyclic 3-phenylpyridine, is an orally active fourth generation himbacine-based antagonist of the protease-activated receptor (PAR)-1, the primary receptor for thrombin on platelets in humans. SCH 530348 is the first in a new class of compounds that inhibit thrombin-mediated platelet aggregation without affecting the enzymatic activity of thrombin on fibrinogen. Preclinical and initial clinical studies have demonstrated this compound to be a highly potent inhibitor of thrombin-induced platelet activation, to have excellent oral bioavailability and to have a favorable safety profile. These data suggest that this compound has the potential to reduce the risk of ischemic events without significantly increasing the rate of bleeding. Two large Phase III clinical outcome trials are currently underway to evaluate the safety and efficacy of SCH 530348 for the management of acute coronary syndromes and the secondary prevention of atherothrombotic events.
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Affiliation(s)
- Marc P Bonaca
- TIMI Study Group, Brigham & Women's Hospital, Boston, MA 02115, USA.
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373
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Smid J, Braun-Dullaeus R, Gawaz M, Langer HF. Platelet interactions as therapeutic targets for prevention of atherothrombosis. Future Cardiol 2010; 5:285-96. [PMID: 19450054 DOI: 10.2217/fca.09.9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Physiologically, platelets perform important tasks to maintain the homeostasis of the vascular wall and the surrounding environment. In pathologic conditions, however, platelets contribute to the formation of atherosclerotic plaques as well as to atherothrombotic events (i.e., acute myocardial infarction). This review aims to elucidate the role of platelets in atherogenesis and atherothrombosis and to provide an insight into current and future strategies for platelet inhibition.
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Affiliation(s)
- Jan Smid
- Universitätsklinik für Kardiologie, Angiologie & Pneumologie, Universitätsklinikum Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany.
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374
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Antiplatelet therapy for atherothrombotic disease: How can we improve the outcomes? J Thromb Thrombolysis 2010; 30:240-9. [DOI: 10.1007/s11239-010-0488-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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375
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Ellison S, Mori J, Barr AJ, Senis YA. CD148 enhances platelet responsiveness to collagen by maintaining a pool of active Src family kinases. J Thromb Haemost 2010; 8:1575-83. [PMID: 20345711 DOI: 10.1111/j.1538-7836.2010.03865.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
SUMMARY BACKGROUND We have previously shown that the receptor-like protein tyrosine phosphatase (PTP) CD148 is essential for initiating glycoprotein VI (GPVI) signaling in platelets. We proposed that CD148 does so by dephosphorylating the C-terminal inhibitory tyrosine of Src family kinases (SFKs). However, this mechanism is complicated by CD148-deficient mouse platelets having a concomitant reduction in GPVI expression. OBJECTIVES To investigate the effect of CD148 on GPVI signaling independent of the decrease in GPVI expression and to further establish the molecular basis of the activatory effect of CD148 and downregulation of GPVI. METHODS CD148-deficient mouse platelets were investigated for functional and biochemical defects. The DT40/NFAT-lucifierase reporter assay was used to analyze the effect of CD148 on GPVI signaling. CD148-SFK interactions and dephosphorylation were quantified using biochemical assays. RESULTS CD148-deficient mouse platelets exhibited reduced collagen-mediated aggregation, secretion and spreading in association with reduced expression of GPVI and FcR gamma-chain and reduced tyrosine phosphorylation. The phosphorylation status of SFKs suggested a global reduction in SFK activity in resting CD148-deficient platelets. Studies in a cell model confirmed that CD148 inhibits GPVI signaling independent of a change in receptor expression and through a mechanism dependent on tyrosine dephosphorylation. Recombinant CD148 dephosphorylated the inhibitory tyrosines of Fyn, Lyn and Src in vitro, although paradoxically it also dephosphorylated the activation loop of SFKs. CONCLUSIONS CD148 plays a critical role in regulating GPVI/FcR gamma-chain expression and maintains a pool of active SFKs in platelets by directly dephosphorylating the C-terminal inhibitory tyrosines of SFKs that is essential for platelet activation.
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Affiliation(s)
- S Ellison
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
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376
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Mao Y, Zhang L, Jin J, Ashby B, Kunapuli SP. Mutational analysis of residues important for ligand interaction with the human P2Y(12) receptor. Eur J Pharmacol 2010; 644:10-6. [PMID: 20599922 DOI: 10.1016/j.ejphar.2010.06.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 05/21/2010] [Accepted: 06/16/2010] [Indexed: 10/19/2022]
Abstract
The P2Y(12) receptor, a Gi protein-coupled receptor, plays a central role in platelet activation. In this study, we did a mutational analysis of residues possibly involved in the ligand interactions with the human P2Y(12) receptor. Mutant receptors were stably expressed in CHO-K1 cells with an HA-tag at the N-terminus. Expression of wild-type and mutant receptors was confirmed by detecting the HA-tag on the cell membrane. Residues in transmembrane helical domains (TMs) 3, 5, 6, and 7, which are homologous to residues important for P2Y(1) receptor activation and ligand recognition, were replaced by site-directed mutagenesis. ADP-induced inhibition of forskolin-stimulated cAMP levels in the presence or absence of antagonist AR-C69931MX were investigated for each of the mutant receptors. F104S and S288P significantly increased agonist-induced receptor function without affecting the antagonism by AR-C69931MX. Arg256 in TM6 and Arg 265 in extracellular loop 3 (EL3) are more important for antagonist recognition than effect on agonist-mediated receptor function. Compared to wild-type P2Y(12) receptor, mutations in Arg 256 or/and Arg 265 significantly increased the sensitivity to antagonist AR-C69931MX. Our study shows that the cytosolic side of TM3 and the exofacial side of TM5 are critical for P2Y(12) receptor function, which is different from P2Y(1). Arg 256 in TM6 and Arg265 in EL3 appear to play a role in antagonist recognition rather than effects on agonist-induced receptor function.
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Affiliation(s)
- Yingying Mao
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, USA
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377
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Adipocytokines in atherothrombosis: focus on platelets and vascular smooth muscle cells. Mediators Inflamm 2010; 2010:174341. [PMID: 20652043 PMCID: PMC2905911 DOI: 10.1155/2010/174341] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 03/14/2010] [Accepted: 04/29/2010] [Indexed: 12/11/2022] Open
Abstract
Visceral obesity is a relevant pathological condition closely associated with high risk of atherosclerotic vascular disease including myocardial infarction and stroke. The increased vascular risk is related also to peculiar dysfunction in the endocrine activity of adipose tissue responsible of vascular impairment (including endothelial dysfunction), prothrombotic tendency, and low-grade chronic inflammation. In particular, increased synthesis and release of different cytokines, including interleukins and tumor necrosis factor-α (TNF-α), and adipokines—such as leptin—have been reported as associated with future cardiovascular events. Since vascular cell dysfunction plays a major role in the atherothrombotic complications in central obesity, this paper aims at focusing, in particular, on the relationship between platelets and vascular smooth muscle cells, and the impaired secretory pattern of adipose tissue.
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378
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Montalescot G. Platelet biology and implications for antiplatelet therapy in atherothrombotic disease. Clin Appl Thromb Hemost 2010; 17:371-80. [PMID: 20566574 DOI: 10.1177/1076029610373366] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Platelet activation is crucial for wound healing at sites of endothelial cell injury and involves multiple factors that mediate platelet recruitment, adherence, and aggregation. Platelet activation in response to atherosclerotic plaque rupture or endothelial cell detachment can result in pathologic thrombus formation and acute ischemic events. Current oral antiplatelet agents, aspirin and adenosine diphosphate (ADP) receptor antagonists, are effective but associated with bleeding as they target activation pathways critical for protective hemostasis and pathologic thrombosis. Each inhibits a single platelet activation pathway and does not impact activation by thrombin. The lack of complete inhibition of platelet function allows continued thrombus formation and recurrent thrombotic events. Inhibition of the protease-activated receptor 1 (PAR-1) stimulated by thrombin offers a rational strategy to achieve more comprehensive platelet inhibition when used in combination with standard-of-care, dual antiplatelet therapy. We expect that this new approach may mitigate bleeding risk, because PAR-1 is not essential for hemostasis.
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379
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Elvers M, Pozgaj R, Pleines I, May F, Kuijpers MJE, Heemskerk JMW, Yu P, Nieswandt B. Platelet hyperreactivity and a prothrombotic phenotype in mice with a gain-of-function mutation in phospholipase Cgamma2. J Thromb Haemost 2010; 8:1353-63. [PMID: 20230420 DOI: 10.1111/j.1538-7836.2010.03838.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Agonist-induced platelet activation involves different signaling pathways leading to the activation of phospholipase C (PLC) beta or PLCgamma2. Activated PLC produces inositol 1,4,5-trisphosphate and diacylglycerol, which trigger Ca(2+) mobilization and the activation of protein kinase C, respectively. PLCbeta is activated downstream of Gq-coupled receptors for soluble agonists with only short interaction times in flowing blood. In contrast, PLCgamma2 becomes activated downstream of receptors that interact with immobilized ligands such as the collagen receptor glycoprotein (GP) VI or activated integrins. OBJECTIVE AND METHODS We speculated that PLCgamma2 activity might be optimized for sustained but submaximal signaling to control relatively slow platelet responses. To test this hypothesis, we analyzed platelets from mice heterozygous for a gain-of-function mutation in the Plcg2 gene (Plcg2(Ali5/+)). RESULTS Plcg2(Ali5/+) platelets showed enhanced Ca(2+) mobilization, integrin activation, granule secretion and phosphatidylserine exposure upon GPVI or C-type lectin-like receptor-2 stimulation. Furthermore, integrin alpha(IIb)beta(3) outside-in signaling was markedly enhanced in the mutant platelets, as shown by accelerated spreading on different matrices and faster clot retraction. These defects translated into virtually unlimited thrombus formation on collagen under flow in vitro and a prothrombotic phenotype in vivo. CONCLUSIONS These results demonstrate that the enzymatic activity of PLCgamma2 is tightly regulated to ensure efficient but limited platelet activation at sites of vascular injury.
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Affiliation(s)
- M Elvers
- Chair of Vascular Medicine, University Clinic, and Rudolf Virchow Center, DFG Research Center for Experimental Biomedicine, University of Würzburg, Germany
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380
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Jackson ECG, McNicol A. Cyclic nucleotides inhibit MAP kinase activity in low-dose collagen-stimulated platelets. Thromb Res 2010; 125:147-51. [PMID: 19595442 DOI: 10.1016/j.thromres.2009.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 06/05/2009] [Accepted: 06/22/2009] [Indexed: 10/20/2022]
Abstract
Collagen-induced platelet activation is a complex process involving multiple signaling pathways. The role(s) of MAP kinases (ERKs and p38(MAPK)) are unclear, although at high, but not low, collagen concentrations p38(MAPK) is involved in cPLA(2)-mediated arachidonic acid release, prior to thromboxane generation. Cyclic nucleotides are conventionally regarded as mediators of platelet inhibition. However recent studies suggested a role for cGMP early in a MAP kinase pathway in platelet activation. In the current study the roles and relationships of MAP kinases, cyclic nucleotides and cPLA(2) in platelet activation by low-dose collagen and a thromboxane analogue (U46619) have been evaluated. Stimulants of neither adenylate cyclase (PGI(2)) nor guanylate cyclase (NaNP) alone had any effect on the basal phosphorylation of either MAP kinase. PGI(2) inhibited ERK/p38(MAPK) phosphorylation in response to both agonists which was unaffected by a cPLA(2) inhibitor (AACOCF(3)). NaNP inhibited collagen-induced ERK/p38(MAPK) phosphorylation, which was enhanced by AACOCF(3) and reversed by a guanylate cyclase inhibitor (ODQ). However NaNP had no effect on U46619-induced p38(MAPK) phosphorylation. Thus adenylate cyclase activation inhibits low-dose collagen-induced MAP kinase phosphorylation both prior, and distal, to thromboxane release. The study also supports an inhibitory, rather than stimulatory, role for guanylate cyclase in platelet signaling.
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Affiliation(s)
- Elke C G Jackson
- Department of Oral Biology, University of Manitoba, 780 Bannatyne Avenue, Winnipeg, Manitoba, Canada R3E 0W2
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381
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Abstract
Mechanisms of platelet inhibition are reviewed with emphasis on the pharmacokinetic and pharmacodynamic determinants of clinical efficacy and safety of antiplatelet drugs. Current developments in antiplatelet therapy are discussed in relation to both primary and secondary prevention of atherothrombotic complications. Interindividual variability in response to antiplatelet agents and new drug targets are outlined within the context of optimizing the balance between the cardiovascular benefits and bleeding risks of antiplatelet therapy. Recent advances in the pharmacogenetics of thienopyridines open the realistic prospect of a personalized choice of the most appropriate antiplatelet agent and tailored dose adjustment for an individual patient.
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Affiliation(s)
- Carlo Patrono
- Department of Pharmacology, Catholic University School of Medicine, Rome, Italy.
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382
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Zhu Z, Zhang Q, Chen L, Ren S, Xu P, Tang Y, Luo D. Higher specificity of the activity of low molecular weight fucoidan for thrombin-induced platelet aggregation. Thromb Res 2010; 125:419-26. [PMID: 20381830 DOI: 10.1016/j.thromres.2010.02.011] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Revised: 02/05/2010] [Accepted: 02/16/2010] [Indexed: 11/28/2022]
Abstract
Algal fucoidans possess a wide variety of biological activities, including anticoagulation and antithrombosis, making them potential candidates for clinical use. We assessed the antiaggregant, anticoagulant and antithrombotic activities and the underlying mechanism of the low- and high-molecular weight fucoidans from the seaweed Laminaria japonica of Qingdao, China (F-Q and HMWF-Q). In the platelets of rats and humans, HMWF-Q demonstrated a pro-aggregation response, whereas F-Q (like the commercially purchased fucoidan (F-S) and heparin), showed an inhibitory effect on thrombin-induced aggregation with an IC(50) of 8 microg/mL, approximately five times lower than those of F-S and heparin. In the activated partial thromboplastin time test, F-Q (40 microg/mL) demonstrated less potent effect than F-S (40 microg/mL) and heparin (7mug/mL); 162+/-2.4s vs. 250+/-13.2s and >300s, p<0.01, respectively. It was also less effective than F-S on inhibiting thrombin catalyzed fibrinogen cleavage (IC(50) 10 microg/mL vs. 2.8 microg/mL) in vitro and rat thrombosis in vivo at 3mg/kg (i.v.). The inhibitory effects of F-Q and heparin on thrombin activity were strikingly enhanced by either antithrombin (AT) or heparin cofactor II (HCII). A direct interaction of F-S with thrombin, and F-Q or heparin with AT was demonstrated in both fluorescence quenching and PAGE analysis. Additionally, a pro-aggregation effect and an enhancement of thrombin activity were also observed with F-S, but not with F-Q or heparin, treatment. These results indicate that F-Q inhibits thrombin via activation of AT and HCII, whereas F-S mainly interacts directly with thrombin. Importantly, F-Q shows a higher specificity for hypoaggregation and a weaker effect for anticoagulant profiles than heparin and F-S. Therefore, F-Q could be a promising candidate for the treatment of thrombosis-related cardiovascular diseases.
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Affiliation(s)
- Zhixiang Zhu
- Department of Pharmacology, Capital Medical University, Beijing 100069, PR China
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383
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Ting HJ, Khasawneh FT. Platelet function and Isoprostane biology. Should isoprostanes be the newest member of the orphan-ligand family? J Biomed Sci 2010; 17:24. [PMID: 20370921 PMCID: PMC2854111 DOI: 10.1186/1423-0127-17-24] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 04/06/2010] [Indexed: 12/19/2022] Open
Abstract
While there have been many reports investigating the biological activity and signaling mechanisms of isoprostanes, their role in biology, particularly in platelets, appears to still be underestimated. Moreover, whether these lipids have their own receptors is still debated, despite multiple reports that discrete receptors for isporpstanes do exist on platelets, vascular tissues, amongst others. This paper provides a review of the important literature of isoprostanes and provides reasoning that isoprostanes should be classified as orphan ligands until their receptor(s) is/are identified.
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Affiliation(s)
- Harold J Ting
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, California 91766, USA
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384
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Smyth EM. Thromboxane and the thromboxane receptor in cardiovascular disease. ACTA ACUST UNITED AC 2010; 5:209-219. [PMID: 20543887 DOI: 10.2217/clp.10.11] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Thromboxane A(2) (TXA(2)), the primary product of COX-1-dependent metabolism of arachidonic acid, mediates its biological actions through the TXA(2) receptor, termed the TP. Irreversible inhibition of platelet COX-1-derived TXA(2) with low-dose aspirin affords protection against primary and secondary vascular thrombotic events, underscoring the central role of TXA(2) as a platelet agonist in cardiovascular disease. The limitations associated with aspirin use include significant gastrointestinal toxicity, bleeding complications, potential interindividual response variability and poor efficacy in some disease states. This, together with the broad role of TXA(2) in cardiovascular disease beyond the platelet, has refocused interest towards additional TXA(2)-associated drug targets, in particular TXA(2) synthase and the TP. The superiority of these agents over low-dose aspirin, in terms of clinical efficacy, tolerability and commercial viability, remain open questions that are the focus of ongoing research.
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Affiliation(s)
- Emer M Smyth
- Institute for Translation Medicine & Therapeutics, University of Pennsylvania, 421 Curie Blvd, 808 BRB 2/3, Philadelphia, PA 19104, USA Tel.: +1 215 573 2323
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385
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Dietrich-Muszalska A, Rabe-Jablonska J, Nowak P, Kontek B. The first- and second-generation antipsychotic drugs affect ADP-induced platelet aggregation. World J Biol Psychiatry 2010; 11:268-75. [PMID: 20218792 DOI: 10.3109/15622970802505792] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Blood platelets play an important role in haemostasis and their hyperaggregability may lead to thrombosis and cardiovascular diseases. Increased incidence of mortality, caused by cardiovascular disease, and the increased risk of thrombotic complication in schizophrenic patients treated with antipsychotics have been reported. The effects of antipsychotic drugs on blood platelet function are not fully explained, therefore the purpose of the present study was to examine and compare the effects of the second-generation antipsychotic drugs used in schizophrenia (clozapine, risperidone and olanzapine), with the effects of the first generation antipsychotic, haloperidol, on the platelet aggregation induced by ADP in vitro. METHODS Blood obtained from healthy volunteers (n=25) collected into sodium citrate was centrifuged (250xg, 10 min) at room temperature to obtain platelet-rich plasma. Aggregation of blood platelets (10 microM ADP) was recorded (Chrono-log aggregometer) in platelet-rich plasma preincubated with antipsychotic drugs (final concentration: clozapine 420 ng/ml, risperidone 65 ng/ml, olanzapine 40 ng/ml, haloperidol 20 ng/ml) for 30 min. RESULTS Our results showed that all tested drugs inhibit platelet aggregation induced by ADP in vitro. Among studied antipsychotic drugs clozapine and olanzapine significantly reduced platelet aggregability in vitro. In comparison with control platelets (without the drug), clozapine inhibited ADP-induced platelet aggregation by 21% (P=3.7x10(-6)) and olanzapine by 18% (P=2.8x10(-4)), respectively. CONCLUSION The obtained results indicate that antipsychotic drugs, especially clozapine and olanzapine, contrary to haloperidol, reduced response of blood platelets to ADP measured as platelet aggregation. This suggests that therapy with such antipsychotics, particularly with second-generation antipsychotics, may partly reduce prothrombotic events associated with the increased platelet activation observed in schizophrenic patients. The mechanism of antiaggregatory influence of antipsychotics requires further studies.
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386
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Multiple alterations of platelet functions dominated by increased secretion in mice lacking Cdc42 in platelets. Blood 2010; 115:3364-73. [PMID: 20139097 DOI: 10.1182/blood-2009-09-242271] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Platelet activation at sites of vascular injury is crucial for hemostasis, but it may also cause myocardial infarction or stroke. Cytoskeletal reorganization is essential for platelet activation and secretion. The small GTPase Cdc42 has been implicated as an important mediator of filopodia formation and exocytosis in various cell types, but its exact function in platelets is not established. Here, we show that the megakaryocyte/platelet-specific loss of Cdc42 leads to mild thrombocytopenia and a small increase in platelet size in mice. Unexpectedly, Cdc42-deficient platelets were able to form normally shaped filopodia and spread fully on fibrinogen upon activation, whereas filopodia formation upon selective induction of GPIb signaling was reduced compared with wild-type platelets. Furthermore, Cdc42-deficient platelets showed enhanced secretion of alpha granules, a higher adenosine diphosphate (ADP)/adenosine triphosphate (ATP) content, increased aggregation at low agonist concentrations, and enhanced aggregate formation on collagen under flow. In vivo, lack of Cdc42 resulted in faster occlusion of ferric chloride-injured arterioles. The life span of Cdc42-deficient platelets was markedly reduced, suggesting increased clearing of the cells under physiologic conditions. These data point to novel multiple functions of Cdc42 in the regulation of platelet activation, granule organization, degranulation, and a specific role in GPIb signaling.
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387
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388
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Maloney SF, Brass LF, Diamond SL. P2Y12 or P2Y1 inhibitors reduce platelet deposition in a microfluidic model of thrombosis while apyrase lacks efficacy under flow conditions. Integr Biol (Camb) 2010; 2:183-92. [PMID: 20473398 DOI: 10.1039/b919728a] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Determination of the patient-specific response to antiplatelet agents facilitates proper dosing for both acute and chronic prophylaxis. "Closed" systems (with or without flow) may fail to predict pharmacological potency in situations where platelets rapidly accumulate under flow conditions at a site of thrombosis ("Open" systems). Using an 8-channel microfluidic flow assay of human whole blood with corn trypsin inhibitor (+/- PPACK) perfused over focal zones of collagen, dose-response curves were measured for pharmacological agents at a wall shear rate of 210 s(-1). The P2Y(1) inhibitor MRS 2179 (IC(50) = 0.233 +/- 0.132 microM) and P2Y(12) inhibitor 2-MeSAMP (IC(50) = 2.558 +/- 0.799 microM) were potent blockers of secondary platelet accumulation under flow, while the P2X(1) inhibitor (NF 449) and apyrase failed to reduce platelet accumulation. MRS 2179 and 2-MeSAMP had undetectable effects on initial platelet adhesion to collagen. Numerical simulation of convective-diffusive transport and apyrase-mediated catalytic degradation of ADP indicated that ultra-high concentrations of apyrase ( approximately 2000 U mL(-1)) would be required to have the same effect under flow as much lower concentrations (1 U mL(-1)) currently used in closed systems (aggregometry or cone-and-plate viscometer). This is the first evaluation of IC(50) values for P2Y(12) and P2Y(1) antagonists under controlled flow conditions. Evaluation of antiplatelet agents in open flow systems demonstrates that inhibition of either ADP by apyrase or antagonism of P2X(1) signaling had no inhibitory effect on platelet accumulation. This technique provides a platform for rapidly investigating effects of antithrombotic therapies simultaneously in a model injury system.
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Affiliation(s)
- S F Maloney
- Department of Chemical and Biomolecular Engineering, Division of Hematology and Oncology, Institute for Medicine and Engineering, 1024 Vagelos Research Laboratories, University of Pennsylvania, Philadelphia, PA 19104, USA
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389
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Ahmed SM, Daulat AM, Meunier A, Angers S. G protein betagamma subunits regulate cell adhesion through Rap1a and its effector Radil. J Biol Chem 2010; 285:6538-51. [PMID: 20048162 DOI: 10.1074/jbc.m109.069948] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The activation of several G protein-coupled receptors is known to regulate the adhesive properties of cells in different contexts. Here, we reveal that Gbetagamma subunits of heterotrimeric G proteins regulate cell-matrix adhesiveness by activating Rap1a-dependent inside-out signals and integrin activation. We show that Gbetagamma subunits enter in a protein complex with activated Rap1a and its effector Radil and establish that this complex is required downstream of receptor stimulation for the activation of integrins and the positive modulation of cell-matrix adhesiveness. Moreover, we demonstrate that Gbetagamma and activated Rap1a promote the translocation of Radil to the plasma membrane at sites of cell-matrix contacts. These results add to the molecular understanding of how G protein-coupled receptors impinge on cell adhesion and suggest that the Gbetagamma x Rap1 x Radil complex plays important roles in this process.
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Affiliation(s)
- Syed M Ahmed
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 3M2, Canada
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390
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Offermanns S. Thrombozytäre Signaltransduktion. Hamostaseologie 2010. [DOI: 10.1007/978-3-642-01544-1_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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391
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Affiliation(s)
- Dominick J. Angiolillo
- Department of Medicine, Division of Cardiology, University of Florida College of Medicine-Jacksonville
| | - Masafumi Ueno
- Department of Medicine, Division of Cardiology, University of Florida College of Medicine-Jacksonville
| | - Shinya Goto
- Department of Medicine Division of Cardiology, Tokai University School of Medicine
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392
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Brass L. Understanding and evaluating platelet function. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2010; 2010:387-396. [PMID: 21239824 DOI: 10.1182/asheducation-2010.1.387] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The contribution of platelets to normal hemostasis and vascular disease is well described. However, recent studies make it clear that much remains to be learned about platelet activation at the single cell and the molecular level, and about the contribution of platelets to inflammation, tumor angiogenesis, and embryonic development. This article is divided into two themes. The first is an overview of current knowledge of the mechanisms that drive platelet function in vivo and a brief summary of some of the emerging ideas that are modifying older views. The second theme is a consideration of the strengths and weaknesses of the tools we have as hematologists to assess platelet function in the clinical setting, identify mechanisms, and evaluate the impact of antiplatelet agents.
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Affiliation(s)
- Lawrence Brass
- Hematology-Oncology Division, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19004, USA.
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393
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Gao Y. The multiple actions of NO. Pflugers Arch 2009; 459:829-39. [DOI: 10.1007/s00424-009-0773-9] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2009] [Revised: 12/01/2009] [Accepted: 12/03/2009] [Indexed: 01/22/2023]
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394
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Sobotková A, Mášová-Chrastinová L, Suttnar J, Štikarová J, Májek P, Reicheltová Z, Kotlín R, Weisel JW, Malý M, Dyr JE. Antioxidants change platelet responses to various stimulating events. Free Radic Biol Med 2009; 47:1707-14. [PMID: 19766712 PMCID: PMC2854508 DOI: 10.1016/j.freeradbiomed.2009.09.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 09/11/2009] [Accepted: 09/14/2009] [Indexed: 11/15/2022]
Abstract
The role of platelets in hemostasis may be influenced by alteration of the platelet redox state-the presence of antioxidants and the formation of reactive oxygen and nitrogen species. We investigated the effects of two antioxidants, resveratrol and trolox, on platelet activation. Trolox and resveratrol inhibited aggregation of washed platelets and platelet-rich plasma activated by ADP, collagen, and thrombin receptor-activating peptide. Resveratrol was a more effective agent in reducing platelet static and dynamic adhesion in comparison with trolox. The antioxidant capacity of resveratrol was, however, the same as that of trolox. After incubation of platelets with antioxidants, the resveratrol intraplatelet concentration was about five times lower than the intracellular concentration of trolox. Although both antioxidants comparably lowered hydroxyl radical and malondialdehyde production in platelets stimulated with collagen, TxB(2) levels were decreased by resveratrol much more effectively than by trolox. Cyclooxygenase 1 was inhibited by resveratrol and not by trolox. Our data indicate that antioxidants, apart from nonspecific redox or radical-quenching mechanisms, inhibit platelet activation also by specific interaction with target proteins. The results also show the importance of studying platelet activation under conditions of real blood flow in contact with reactive surfaces, e.g., using dynamic adhesion experiments.
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Affiliation(s)
- Alžběta Sobotková
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
| | - Leona Mášová-Chrastinová
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
- Corresponding author. Fax: +42 0221977208. (L. Mášová-Chrastinová)
| | - Jiří Suttnar
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
| | - Jana Štikarová
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
| | - Pavel Májek
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
| | - Zuzana Reicheltová
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
| | - Roman Kotlín
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
| | - John W. Weisel
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6058, USA
| | - Martin Malý
- Department of Cardiology, Motol University Hospital, V úvalu 84, 15006 Prague 5, Czech Republic
| | - Jan E. Dyr
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 00 Prague 2, Czech Republic
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395
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Platelets contribute to postnatal occlusion of the ductus arteriosus. Nat Med 2009; 16:75-82. [DOI: 10.1038/nm.2060] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 10/23/2009] [Indexed: 12/24/2022]
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396
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Abstract
Clinical manifestations of atherothrombotic disease, such as acute coronary syndromes, cerebrovascular events, and peripheral arterial disease, are major causes of mortality and morbidity worldwide. Platelet activation and aggregation are ultimately responsible for the progression and clinical presentations of atherothrombotic disease. The current standard of care, dual oral antiplatelet therapy with aspirin and the P2Y(12) adenosine diphosphate (ADP) receptor inhibitor clopidogrel, has been shown to improve outcomes in patients with atherothrombotic disease. However, aspirin and P2Y(12) inhibitors target the thromboxane A(2) and the ADP P2Y(12) platelet activation pathways and minimally affect other pathways, while agonists such as thrombin, considered to be the most potent platelet activator, continue to stimulate platelet activation and thrombosis. This may help explain why patients continue to experience recurrent ischaemic events despite receiving such therapy. Furthermore, aspirin and P2Y(12) receptor antagonists are associated with bleeding risk, as the pathways they inhibit are critical for haemostasis. The challenge remains to develop therapies that more effectively inhibit platelet activation without increasing bleeding complications. The inhibition of the protease-activated receptor-1 (PAR-1) for thrombin has been shown to inhibit thrombin-mediated platelet activation without increasing bleeding in pre-clinical models and small-scale clinical trials. PAR-1 inhibition in fact does not interfere with thrombin-dependent fibrin generation and coagulation, which are essential for haemostasis. Thus PAR-1 antagonism coupled with existing dual oral antiplatelet therapy may potentially offer more comprehensive platelet inhibition without the liability of increased bleeding.
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Affiliation(s)
- Dominick J Angiolillo
- Division of Cardiology, Department of Medicine, University of Florida College of Medicine -Jacksonville, Shands Jacksonville, 655 West 8th St, Jacksonville, FL 32209, USA.
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397
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Fabre JE, Gurney ME. Limitations of current therapies to prevent thrombosis: a need for novel strategies. MOLECULAR BIOSYSTEMS 2009; 6:305-15. [PMID: 20094648 DOI: 10.1039/b914375k] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Bleeding limits the benefit of current anti-platelet drugs for preventing heart attacks and stroke. Aspirin and clopidogrel, the two most widely prescribed anti-platelet drugs, are metabolized to active compounds that covalently and irreversibly modify their respective therapeutic targets (COX1 and P2Y12). The enduring effects of aspirin and clopidogrel are of concern in patients receiving anti-platelet therapy who require emergency surgery as this places them at greater risk of haemorrhage. As clopidogrel must be activated by cytochrome P450 metabolism, recent pharmacogenomic studies have revealed that patients lacking a functional allele of CYP2C19 derive no therapeutic benefit from the drug. Prasugrel, a second generation thienopyridine, whose bioconversion is not affected by CYP genetic polymorphism, demonstrates improved clinical benefit, but with increased bleeding risk. Anti-platelet drugs currently in cardiovascular trials that may have reduced bleeding risk include reversible P2Y12 antagonists (cangrelor, ticagrelor, and elinogrel), a PAR1 antagonist (SCH 530 348) and an EP3 antagonist (DG-041). The platelet EP3 receptor for prostaglandin E(2) is an attractive therapeutic target as EP3 antagonists may selectively avert thrombosis over atherosclerotic plaques without affecting bleeding risk.
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Affiliation(s)
- Jean-Etienne Fabre
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Institut National de la Santé et de la Recherche Médicale U596, Centre National de la Recherche Scientifique UMR7104, Université Louis Pasteur, 67400 Illkirch, France.
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398
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Collet JP, Montalescot G. Platelet function testing and implications for clinical practice. J Cardiovasc Pharmacol Ther 2009; 14:157-69. [PMID: 19721130 DOI: 10.1177/1074248409339309] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Platelets are key mediators in the pathophysiology of atherothrombotic disease. Inappropriate platelet activation can lead to thrombosis and ischemic events. Platelet function testing has been used to monitor patient response to antiplatelet therapy. Variability in response to antiplatelet therapy may be due in part to incomplete inhibition of targeted pathways (thromboxane A(2) and adenosine diphosphate [ADP]) by currently available agents (aspirin and P2Y(12) ADP receptor antagonists). Low responsiveness to antiplatelet therapy (as measured in various platelet function assays) correlates with a high rate of ischemic events. However, tailoring treatment based on platelet response remains to be definitively proven in clinical trials, correlations between assays are modest, and concordance in defining suboptimal response is poor. Additional studies are needed to determine whether changes in therapy based on results of platelet function testing improve clinical outcomes, and thus will determine whether broader use of platelet function testing in clinical practice is warranted.
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Affiliation(s)
- Jean-Philippe Collet
- Institut de Cardiologie, Centre Hospitalier Universitaire Pitié-Salpêtrière, Paris, France
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399
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Gardner M, Palmer J, Manrique C, Lastra G, Gardner DW, Sowers JR. Utility of aspirin therapy in patients with the cardiometabolic syndrome and diabetes. ACTA ACUST UNITED AC 2009; 4:96-101. [PMID: 19614796 DOI: 10.1111/j.1559-4572.2008.00037.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Paralleling the rise in obesity, the cardiometabolic syndrome is a rapidly growing health problem in the United States. There is a 3-fold increase in the prevalence of coronary heart disease, myocardial infarction, and stroke due to the coagulation, hemodynamic, and metabolic abnormalities seen in these individuals. The use of aspirin for secondary prevention and, to a lesser degree, primary prevention of cardiovascular events is a well-established standard of care. However, in patients with diabetes or the cardiometabolic syndrome, the role of aspirin in prevention of cardiovascular events remains controversial. In this review, the authors examine the clinical trial data on the use of aspirin in diabetes and the cardiometabolic syndrome for cardiovascular protection. They also explore, in addition to aspirin's effects on platelet aggregation, some of the mechanisms by which aspirin may favorably alter the course of atherosclerosis, effects on endothelial function, and glycemia.
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Affiliation(s)
- Michael Gardner
- Diabetes and Cardiovascular Center, University of Missouri School of Medicine and Truman VA Hospital, Columbia, MO 65212, USA.
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400
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San Juan A, Bala M, Hlawaty H, Portes P, Vranckx R, Feldman LJ, Letourneur D. Development of a Functionalized Polymer for Stent Coating in the Arterial Delivery of Small Interfering RNA. Biomacromolecules 2009; 10:3074-80. [DOI: 10.1021/bm900740g] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Aurélie San Juan
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
| | - Madiha Bala
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
| | - Hanna Hlawaty
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
| | - Patrick Portes
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
| | - Roger Vranckx
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
| | - Laurent J. Feldman
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
| | - Didier Letourneur
- Inserm, U698, Bio-ingénierie Cardiovasculaire, Université Paris 7, Paris, France, and Université Paris 13, Villetaneuse, France, Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions (CNRS UPR 1311), Université Paris 13, Villetaneuse, France, and AP-HP, Hôpital Bichat, Département de Cardiologie, Paris, France
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