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Discovering anti-platelet drug combinations with an integrated model of activator-inhibitor relationships, activator-activator synergies and inhibitor-inhibitor synergies. PLoS Comput Biol 2015; 11:e1004119. [PMID: 25875950 PMCID: PMC4405222 DOI: 10.1371/journal.pcbi.1004119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 01/08/2015] [Indexed: 12/01/2022] Open
Abstract
Identifying effective therapeutic drug combinations that modulate complex
signaling pathways in platelets is central to the advancement of effective
anti-thrombotic therapies. However, there is no systems model of the platelet
that predicts responses to different inhibitor combinations. We developed an
approach which goes beyond current inhibitor-inhibitor combination screening to
efficiently consider other signaling aspects that may give insights into the
behaviour of the platelet as a system. We investigated combinations of platelet
inhibitors and activators. We evaluated three distinct strands of information,
namely: activator-inhibitor combination screens (testing a panel of inhibitors
against a panel of activators); inhibitor-inhibitor synergy screens; and
activator-activator synergy screens. We demonstrated how these analyses may be
efficiently performed, both experimentally and computationally, to identify
particular combinations of most interest. Robust tests of activator-activator
synergy and of inhibitor-inhibitor synergy required combinations to show
significant excesses over the double doses of each component. Modeling
identified multiple effects of an inhibitor of the P2Y12 ADP receptor, and
complementarity between inhibitor-inhibitor synergy effects and
activator-inhibitor combination effects. This approach accelerates the mapping
of combination effects of compounds to develop combinations that may be
therapeutically beneficial. We integrated the three information sources into a
unified model that predicted the benefits of a triple drug combination targeting
ADP, thromboxane and thrombin signaling. Drugs are often used in combinations, but establishing the best combinations is a
considerable challenge for basic and clinical research. Anti-platelet therapies
reduce thrombosis and heart attacks by lowering the activation of platelet
cells. We wanted to find good drug combinations, but a full systems model of the
platelet is absent, so we had no good predictions of how particular combinations
might behave. Instead, we put together three sources of knowledge. The first
concerned what inhibitors act on what activators; the second concerned what
pairs of activators synergise together (having a bigger effect than expected);
and the third concerned what pairs of inhibitors synergise together. We
implemented an efficient experimental approach to collect this information from
experiments on platelets. We developed a statistical model that brought these
separate results together. This gave us insights into how platelet inhibitors
act. For example, an inhibitor of an ADP receptor showed multiple effects. We
also worked out from the model what further (triple) combinations of drugs may
be most efficient. We predicted, and then tested experimentally, the effects of
a triple drug combination. This simultaneously inhibited the platelet’s
responses to three stimulants that it encounters during coronary thrombosis,
namely ADP, thromboxane and thrombin.
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252
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Yang H, Xu S, Li J, Wang L, Wang X. Potassium 2-(1-hydroxypentyl)-benzoate inhibits ADP-induced rat platelet aggregation through P2Y1-PLC signaling pathways. Naunyn Schmiedebergs Arch Pharmacol 2015; 388:983-90. [PMID: 25787305 DOI: 10.1007/s00210-015-1113-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 03/03/2015] [Indexed: 01/09/2023]
Abstract
Potassium 2-(1-hydroxypenty1)-benzoate (dl-PHPB) is a new drug candidate for treatment of ischemic stroke with antiplatelet effect. In this study, we investigated the mechanisms of dl-PHPB in inhibiting platelet aggregation. The ADP-activated P2Y1-Gq-PLC and P2Y12-Gi-AC pathways were observed, respectively. Intravenous injection of dl-PHPB (1.3, 3.9, 12.9 mg/kg) significantly inhibited ADP-, collagen-, and arachidonic acid-induced rat platelet aggregation in a dose-dependent manner, and dl-PHPB had a relatively more potent inhibitory effect on ADP-induced rat platelet aggregation than other agonists. Dl-PHPB also showed a decreased expression of CD62P (a marker for platelet activation) mediated by ADP. Both dl-PHPB and ticlopidine (P2Y12 receptor antagonist) decreased cytoplasmic Ca(2+) concentration. But, dl-PHPB did not reverse the inhibition of PGE1-induced platelet cAMP formation by ADP, which was different from ticlopidine. Further, dl-PHPB instead of ticlopidine showed increasing phospholipase C-β phosphorylation (ser(1105)). The m-3M3FBS, a phospholipase C activator, attenuated the inhibitory effect of dl-PHPB on ADP-induced platelet aggregation and enhanced IP1 accumulation in rat platelets. Dl-PHPB decreased IP1 accumulation induced by ADP but had no effect on IP1 level enhanced by m-3M3FBS. Our results suggest that dl-PHPB has a potent antiplatelet effect, which is mainly through blockade of P2Y1 receptor-PLC-IP3 pathway and decreasing cytoplasmic calcium.
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Affiliation(s)
- Hongyan Yang
- State Key laboratory of Bioactive Substances and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Xiannongtan Street, Beijing, 100050, China
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253
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Nording HM, Seizer P, Langer HF. Platelets in inflammation and atherogenesis. Front Immunol 2015; 6:98. [PMID: 25798138 PMCID: PMC4351644 DOI: 10.3389/fimmu.2015.00098] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 02/19/2015] [Indexed: 12/12/2022] Open
Abstract
Platelets contribute to processes beyond thrombus formation and may play a so far underestimated role as an immune cell in various circumstances. This review outlines immune functions of platelets in host defense, but also how they may contribute to mechanisms of infectious diseases. A particular emphasis is placed on the interaction of platelets with other immune cells. Furthermore, this article outlines the features of atherosclerosis as an inflammatory vascular disease highlighting the role of platelet crosstalk with cellular and soluble factors involved in atheroprogression. Understanding, how platelets influence these processes of vascular remodeling will shed light on their role for tissue homeostasis beyond intravascular thrombosis. Finally, translational implications of platelet-mediated inflammation in atherosclerosis are discussed.
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Affiliation(s)
- Henry M. Nording
- University Clinic for Cardiology and Cardiovascular Medicine, Eberhard Karls-University Tübingen, Tübingen, Germany
- Section for Cardioimmunology, Eberhard Karls-University Tübingen, Tübingen, Germany
| | - Peter Seizer
- University Clinic for Cardiology and Cardiovascular Medicine, Eberhard Karls-University Tübingen, Tübingen, Germany
| | - Harald F. Langer
- University Clinic for Cardiology and Cardiovascular Medicine, Eberhard Karls-University Tübingen, Tübingen, Germany
- Section for Cardioimmunology, Eberhard Karls-University Tübingen, Tübingen, Germany
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254
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Inamdar V, Patel A, Manne BK, Dangelmaier C, Kunapuli SP. Characterization of UBO-QIC as a Gαq inhibitor in platelets. Platelets 2015; 26:771-8. [PMID: 25734215 DOI: 10.3109/09537104.2014.998993] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Gαq plays an important role in platelet activation by agonists such as thrombin, adenosine diphosphate (ADP) and thromboxane. The significance of Gαq signaling in platelets was established using YM254890, a Gαq/11-specific inhibitor and Gαq knockout murine platelets. However, YM-254890 is no longer available for investigators and there is a need to characterize other Gαq inhibitors. The aim of this study is to characterize the specificity of a compound, {L-threonine,(3R)-N-acetyl-3-hydroxy-L-leucyl-(aR)-a-hydroxybenzenepropanoyl-2,3-idehydro-N-methylalanyl-L-alanyl-N-methyl-L-alanyl-(3R)-3-[[(2S,3R)-3-hydroxy-4-methyl-1-oxo-2-[(1-oxopropyl)amino]pentyl]oxy]-L-leucyl-N,O-dimethyl-,(7 → 1)-lactone (9CI)} (UBO-QIC), as a Gαq inhibitor in platelets. Human platelets treated with UBO-QIC showed a concentration-dependent inhibition of platelet aggregation and secretion by protease-activated receptors (PAR) agonists, U46619 and ADP. UBO-QIC also abolished Gαq pathway signaling events such as calcium mobilization and pleckstrin phosphorylation. UBO-QIC had no nonspecific effects on the Gα12/13 pathway since platelet shape change was intact in Gαq knockout murine platelets stimulated with PAR agonists in the presence of the inhibitor. In addition, UBO-QIC-treated platelets did not affect collagen-related peptide-induced platelet activation suggesting that this inhibitor had no non-specific effects on the GPVI pathway. Furthermore, Akt phosphorylation downstream of the Gαi and Gαz pathways, and vasodilator-stimulated phosphoprotein phosphorylation downstream of the Gαs pathway were not inhibited in UBO-QIC-treated platelets. UBO-QIC is a specific inhibitor for Gαq, which can be a useful tool for investigating Gαq-coupled receptor signaling pathways in platelets.
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Affiliation(s)
- Vaishali Inamdar
- a Sol Sherry Thrombosis Research Center and Department of Physiology , Temple University School of Medicine , Philadelphia , PA , USA
| | - Akruti Patel
- a Sol Sherry Thrombosis Research Center and Department of Physiology , Temple University School of Medicine , Philadelphia , PA , USA
| | - Bhanu Kanth Manne
- a Sol Sherry Thrombosis Research Center and Department of Physiology , Temple University School of Medicine , Philadelphia , PA , USA
| | - Carol Dangelmaier
- a Sol Sherry Thrombosis Research Center and Department of Physiology , Temple University School of Medicine , Philadelphia , PA , USA
| | - Satya P Kunapuli
- a Sol Sherry Thrombosis Research Center and Department of Physiology , Temple University School of Medicine , Philadelphia , PA , USA
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255
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Reddi BA, Iannella SM, O'Connor SN, Deane AM, Willoughby SR, Wilson DP. Attenuated platelet aggregation in patients with septic shock is independent from the activity state of myosin light chain phosphorylation or a reduction in Rho kinase-dependent inhibition of myosin light chain phosphatase. Intensive Care Med Exp 2015. [PMID: 26215804 PMCID: PMC4512995 DOI: 10.1186/s40635-014-0037-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Background Impaired coagulation contributes to the morbidity and mortality associated with septic shock. Whether abnormal platelet contraction adds to the bleeding tendency is unknown. Platelets contract when Ca2+-dependent myosin light chain kinase (MLCK) phosphorylates Ser19 of myosin light chain (MLC20), promoting actin-myosin cross-bridge cycling. Contraction is opposed when myosin light chain phosphatase (MLCP) dephosphorylates MLC20. It is thought that Rho kinase (ROK) inhibits MLCP by phosphorylating Thr855 of the regulatory subunit MYPT, favouring platelet contraction. This study tested the hypotheses that in septic shock, (i) platelet function is inversely correlated with illness severity and (ii) ROK-dependent MLCP inhibition and myosin light chain phosphorylation are reduced. Methods Blood was sampled from non-septic shock patients and patients in the first 24 h of septic shock. Platelet function was assessed using whole blood impedance aggregation induced by 1) ADP (1.6 and 6.5 μM), 2) thrombin receptor-activating protein (TRAP; 32 μM), 3) arachidonic acid (500 μM) and 4) collagen (3.2 μg/ml). Arachidonic acid-induced aggregation was measured in the presence of the ROK inhibitor Y27632. Illness severity was evaluated using sequential organ failure assessment (SOFA) and acute physiology and chronic health evaluation (APACHE) II scores. Western blot analysis of [Ser19]MLC20 and [Thr855]MYPT phosphorylation quantified activation and inhibition of platelet MLC20 and MLCP, respectively. Data were analysed using Spearman's rank correlation coefficient, Student's t-test and Mann-Whitney test; p < 0.05 was considered significant. Results Agonist-induced aggregation was attenuated in septic shock patients (n = 22 to 34; p < 0.05). Aggregation correlated inversely with SOFA and APACHE II scores (n = 34; p < 0.05). Thr855 phosphorylation of MYPT from unstimulated platelets was not decreased in patients with septic shock (n = 22 to 24). Both septic shock and ROK inhibition attenuated arachidonic acid-induced platelet aggregation independent of changes in [Ser19]MLC20 and [Thr855]MYPT phosphorylation (n = 14). Conclusions Impairment of whole blood aggregation in patients within the first 24 h of septic shock was correlated with SOFA and APACHE II scores. Attenuated aggregation was independent of molecular evidence of diminished platelet contraction or reduced ROK inhibition of MLCP. Efforts to restore platelet function in septic shock should therefore focus on platelet adhesion and degranulation.
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Affiliation(s)
- Benjamin Aj Reddi
- Intensive Care Unit, Royal Adelaide Hospital, North Terrace, Adelaide, South Australia, 5000, Australia,
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256
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Elvers M. RhoGAPs and Rho GTPases in platelets. Hamostaseologie 2015; 36:168-77. [PMID: 25639730 DOI: 10.5482/hamo-14-09-0046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 01/13/2015] [Indexed: 01/03/2023] Open
Abstract
Platelet cytoskeletal reorganization is essential for platelet adhesion and thrombus formation in hemostasis and thrombosis. The Rho GTPases RhoA, Rac1 and Cdc42 are the main players in cytoskeletal dynamics of platelets responsible for the formation of filopodia and lamellipodia to strongly increase the platelet surface upon activation. They are involved in platelet activation and aggregate formation including platelet secretion, integrin activation and arterial thrombus formation. The activity of Rho GTPases is tightly controlled by different proteins such as GTPase-activating proteins (GAPs). GAPs stimulate GTP hydrolysis to terminate Rho signaling. The role and impact of GAPs in platelets is not well-defined and many of the RhoGAPs identified are not known to be present in platelets or to have any function in platelets. The recently identified RhoGAPs Oligophrenin1 (OPHN1) and Nadrin regulate the activity of RhoA, Rac1 and Cdc42 and subsequent platelet cytoskeletal reorganization, platelet activation and thrombus formation. In the last years, the analysis of genetically modified mice helped to gain the understanding of Rho GTPases and their regulators in cytoskeletal rearrangements and other Rho mediated cellular processes in platelets.
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Affiliation(s)
- Margitta Elvers
- Margitta Elvers, Ph.D., Department of Clinical and Experimental Hemostasis, Hemotherapy and Transfusion Medicine, Heinrich-Heine-University Duesseldorf, Moorenstr. 5, 40225 Duesseldorf, Germany, Tel. +49/(0)211/81-08851, Fax -17498., E-mail:
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257
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Gurbel PA, Kuliopulos A, Tantry US. G-protein-coupled receptors signaling pathways in new antiplatelet drug development. Arterioscler Thromb Vasc Biol 2015; 35:500-12. [PMID: 25633316 DOI: 10.1161/atvbaha.114.303412] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Platelet G-protein-coupled receptors influence platelet function by mediating the response to various agonists, including ADP, thromboxane A2, and thrombin. Blockade of the ADP receptor, P2Y12, in combination with cyclooxygenase-1 inhibition by aspirin has been among the most widely used pharmacological strategies to reduce cardiovascular event occurrence in high-risk patients. The latter dual pathway blockade strategy is one of the greatest advances in the field of cardiovascular medicine. In addition to P2Y12, the platelet thrombin receptor, protease activated receptor-1, has also been recently targeted for inhibition. Blockade of protease activated receptor-1 has been associated with reduced thrombotic event occurrence when added to a strategy using P2Y12 and cyclooxygenase-1 inhibition. At this time, the relative contributions of these G-protein-coupled receptor signaling pathways to in vivo thrombosis remain incompletely defined. The observation of treatment failure in ≈10% of high-risk patients treated with aspirin and potent P2Y12 inhibitors provides the rationale for targeting novel pathways mediating platelet function. Targeting intracellular signaling downstream from G-protein-coupled receptor receptors with phosphotidylionisitol 3-kinase and Gq inhibitors are among the novel strategies under investigation to prevent arterial ischemic event occurrence. Greater understanding of the mechanisms of G-protein-coupled receptor-mediated signaling may allow the tailoring of antiplatelet therapy.
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Affiliation(s)
- Paul A Gurbel
- From the Sinai Center for Thrombosis Research, Sinai Hospital of Baltimore, MD (P.A.G., U.S.T.); and Center for Hemostasis and Thrombosis Research, Tufts Medical Center, Boston, MA (A.K.).
| | - Athan Kuliopulos
- From the Sinai Center for Thrombosis Research, Sinai Hospital of Baltimore, MD (P.A.G., U.S.T.); and Center for Hemostasis and Thrombosis Research, Tufts Medical Center, Boston, MA (A.K.)
| | - Udaya S Tantry
- From the Sinai Center for Thrombosis Research, Sinai Hospital of Baltimore, MD (P.A.G., U.S.T.); and Center for Hemostasis and Thrombosis Research, Tufts Medical Center, Boston, MA (A.K.)
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258
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Noris M, Mele C, Remuzzi G. Podocyte dysfunction in atypical haemolytic uraemic syndrome. Nat Rev Nephrol 2015; 11:245-52. [PMID: 25599621 DOI: 10.1038/nrneph.2014.250] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Genetic or autoimmune defects that lead to dysregulation of the alternative pathway of complement have been associated with the development of atypical haemolytic uraemic syndrome (aHUS), which is characterized by thrombocytopenia, haemolytic anaemia and acute kidney injury. The relationship between aHUS, podocyte dysfunction and the resultant proteinuria has not been adequately investigated. However, the report of mutations in diacylglycerol kinase ε (DGKE) as a cause of recessive infantile aHUS characterized by proteinuria, highlighted podocyte dysfunction as a potential complication of aHUS. DGKE deficiency was originally thought to trigger aHUS through pathogenetic mechanisms distinct from complement dysregulation; however, emerging findings suggest an interplay between DGKE and complement systems. Podocyte dysfunction with nephrotic-range proteinuria can also occur in forms of aHUS associated with genetic or autoimmune complement dysregulation without evidence of DGKE mutations. Furthermore, proteinuric glomerulonephritides can be complicated by aHUS, possibly as a consequence of podocyte dysfunction inducing endothelial injury and prothrombotic abnormalities.
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Affiliation(s)
- Marina Noris
- IRCCS Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Centre for Rare Diseases "Aldo e Cele Daccò", Via Camozzi 3, 24020, Ranica, Bergamo, Italy
| | - Caterina Mele
- IRCCS Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Centre for Rare Diseases "Aldo e Cele Daccò", Via Camozzi 3, 24020, Ranica, Bergamo, Italy
| | - Giuseppe Remuzzi
- IRCCS Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Centre for Rare Diseases "Aldo e Cele Daccò", Via Camozzi 3, 24020, Ranica, Bergamo, Italy
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259
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Ro JY, Ryu JH, Park HJ, Cho HJ. Onion (Allium cepa L.) peel extract has anti-platelet effects in rat platelets. SPRINGERPLUS 2015; 4:17. [PMID: 25628983 PMCID: PMC4303602 DOI: 10.1186/s40064-015-0786-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/02/2015] [Indexed: 11/10/2022]
Abstract
The effects of onion peel extract (OPE) in collagen (5 μg/mL)-stimulated washed rat platelet aggregation were investigated. OPE inhibited platelet aggregation via inhibition of aggregation-inducing molecules, intracellular Ca(2+) and thromboxane A2 (TXA2) by blocking cyclooxygenase-1 (COX-1) and TXA2 synthase (TXAS) activities in a dose-dependent manner. In addition, OPE elevated the formation of cyclic adenosine monophosphate (cAMP), aggregation-inhibiting molecule, but not cyclic guanosine monophosphate (cGMP). High performance liquid chromatography (HPLC) analysis of OPE revealed that OPE contains quercetin, one of the major flavonoids, which has anti-platelet effect. In conclusion, we suggest that OPE is an effective inhibitor of collagen-stimulated platelet aggregation in vitro. Therefore, it can be a promising and safe strategy for anti-cardiovascular diseases.
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Affiliation(s)
- Ju-Ye Ro
- Department of Biomedical Laboratory Science, College of Medical Science, Konyang University, 685, Gasuwon-dong, Seo-gu, Daejeon 302-718 Korea
| | - Jin-Hyeob Ryu
- Department of Biomedical Laboratory Science, College of Medical Science, Konyang University, 685, Gasuwon-dong, Seo-gu, Daejeon 302-718 Korea.,Present address: Department of Microbiology and Immunology, Institute of Medical Science, Tokyo University, Minato-ku, Tokyo, 108-8639 Japan
| | - Hwa-Jin Park
- Department of Biomedical Laboratory Science, College of Biomedical Science and Engineering and Regional Research Center, Inje University, 607, Obang-dong, Gimhae, Gyungnam 621-749 Korea
| | - Hyun-Jeong Cho
- Department of Biomedical Laboratory Science, College of Medical Science, Konyang University, 685, Gasuwon-dong, Seo-gu, Daejeon 302-718 Korea
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260
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van Rooy MJ, Pretorius E. Metabolic syndrome, platelet activation and the development of transient ischemic attack or thromboembolic stroke. Thromb Res 2015; 135:434-42. [PMID: 25601172 DOI: 10.1016/j.thromres.2014.12.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 12/26/2014] [Accepted: 12/29/2014] [Indexed: 10/24/2022]
Abstract
Stroke is the second most common cause of mortality in the world today, where transient ischemic attack (TIA) is a period of focal ischemia, the symptoms of which resemble a thromboembolic stroke. Contrary to stroke, TIA symptoms typically last less than one hour and necrosis is absent. Stroke is often preceded by TIA, making it an important predictor of future ischemic events. The causal role of atherosclerosis in the development of TIA is well established, however, research indicates that the atherosclerotic process begins years earlier with the development of metabolic syndrome, which affects approximately 45% of the adult population worldwide. Metabolic syndrome is present if three or more of the following is present: increased waist circumference, increased triglycerides, decreased HDL, increased fasting glucose and hypertension. This syndrome causes systemic inflammation that activates the coagulation system and may cause the formation of pathological thrombi. The role of platelets in stroke has been studied and platelet activation pathways identified. ADP and thromboxane A(2) are the most common activators of platelets in normal physiology. Several pharmacological treatments have been employed to prevent the activation of platelets, the most common of which include aspirin and P2Y(12)-inhibitors. Although treatment is administered strokes and subsequent TIAs are very common in individuals that suffered an initial event. This indicates that research needs to be done in order to elucidate new therapeutic targets, but also to better treat ischemic events to not only decrease the amount of recurring events but also decrease stroke mortality worldwide.
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Affiliation(s)
- Mia-Jeanne van Rooy
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia 0007, South Africa
| | - Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia 0007, South Africa.
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261
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A novel role of Eruca sativa Mill. (rocket) extract: antiplatelet (NF-κB inhibition) and antithrombotic activities. Nutrients 2014; 6:5839-52. [PMID: 25514563 PMCID: PMC4277002 DOI: 10.3390/nu6125839] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/24/2014] [Accepted: 11/25/2014] [Indexed: 11/17/2022] Open
Abstract
Background: Epidemiological studies have shown the prevention of cardiovascular diseases through the regular consumption of vegetables. Eruca sativa Mill., commonly known as rocket, is a leafy vegetable that has anti-inflammatory activity. However, its antiplatelet and antithrombotic activities have not been described. Methods: Eruca sativa Mill. aqueous extract (0.1 to 1 mg/mL), was evaluated on human platelets: (i) P-selectin expression by flow cytometry; (ii) platelet aggregation induced by ADP, collagen and arachidonic acid; (iii) IL-1β, TGF-β1, CCL5 and thromboxane B2 release; and (iv) activation of NF-κB and PKA by western blot. Furthermore, (v) antithrombotic activity (200 mg/kg) and (vi) bleeding time in murine models were evaluated. Results: Eruca sativa Mill. aqueous extract (0.1 to 1 mg/mL) inhibited P-selectin expression and platelet aggregation induced by ADP. The release of platelet inflammatory mediators (IL-1β, TGF-β1, CCL5 and thromboxane B2) induced by ADP was inhibited by Eruca sativa Mill. aqueous extract. Furthermore, Eruca sativa Mill. aqueous extract inhibited NF-κB activation. Finally, in murine models, Eruca sativa Mill. aqueous extract showed significant antithrombotic activity and a slight effect on bleeding time. Conclusion: Eruca sativa Mill. presents antiplatelet and antithrombotic activity.
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262
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Affiliation(s)
- Kushal U Naik
- a Delaware Cardiovascular Research Center ; Department of Biological Sciences; Department of Chemistry and Biochemistry; Delaware Biotechnology Institute; University of Delaware ; Newark, DE USA
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263
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Jurk K. Analysis of platelet function and dysfunction. Hamostaseologie 2014; 35:60-72. [PMID: 25482925 DOI: 10.5482/hamo-14-09-0047] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 11/21/2014] [Indexed: 12/17/2022] Open
Abstract
Although platelets act as central players of haemostasis only their cross-talk with other blood cells, plasma factors and the vascular compartment enables the formation of a stable thrombus. Multiple activation processes and complex signalling networks are responsible for appropriate platelet function. Thus, a variety of platelet function tests are available for platelet research and diagnosis of platelet dysfunction. However, universal platelet function tests that are sensitive to all platelet function defects do not exist and therefore diagnostic algorithms for suspected platelet function disorders are still recommended in clinical practice. Based on the current knowledge of human platelet activation this review evaluates point-of-care related screening tests in comparison with specific platelet function assays and focuses on their diagnostic utility in relation to severity of platelet dysfunction. Further, systems biology-based platelet function methods that integrate global and specific analysis of platelet vessel wall interaction (advanced flow chamber devices) and post-translational modifications (platelet proteomics) are presented and their diagnostic potential is addressed.
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Affiliation(s)
- K Jurk
- Priv.-Doz. Dr. rer. nat. Kerstin Jurk, Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg-University, Langenbeckstr. 1, 55131 Mainz, Germany, E-mail:
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264
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The sweeter aspects of platelet activation: A lectin-based assay reveals agonist-specific glycosylation patterns. Biochim Biophys Acta Gen Subj 2014; 1840:3423-33. [PMID: 25175560 DOI: 10.1016/j.bbagen.2014.08.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 08/17/2014] [Accepted: 08/21/2014] [Indexed: 01/28/2023]
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265
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Nisar SP, Jones ML, Cunningham MR, Mumford AD, Mundell SJ. Rare platelet GPCR variants: what can we learn? Br J Pharmacol 2014; 172:3242-53. [PMID: 25231155 DOI: 10.1111/bph.12941] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 09/05/2014] [Accepted: 09/09/2014] [Indexed: 12/31/2022] Open
Abstract
Platelet-expressed GPCRs are critical regulators of platelet function. Pharmacological blockade of these receptors forms a powerful therapeutic tool in the treatment and prevention of arterial thrombosis associated with coronary atherosclerosis and ischaemic stroke. However, anti-thrombotic drug therapy is associated with high inter-patient variability in therapeutic response and adverse bleeding side effects. In order to optimize the use of existing anti-platelet drugs and to develop new therapies, more detailed knowledge is required relating to the molecular mechanisms that regulate GPCR and therefore platelet function. One approach has been to identify rare, function-disrupting mutations within key platelet proteins in patients with bleeding disorders. In this review, we describe how an integrated functional genomics strategy has contributed important structure-function information about platelet GPCRs with specific emphasis upon purinergic and thromboxane A2 receptors. We also discuss the potential implications these findings have for pharmacotherapy and for understanding the molecular basis of mild bleeding disorders.
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Affiliation(s)
- S P Nisar
- School of Physiology and Pharmacology, University of Bristol, Bristol, UK
| | - M L Jones
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - M R Cunningham
- School of Physiology and Pharmacology, University of Bristol, Bristol, UK
| | - A D Mumford
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - S J Mundell
- School of Physiology and Pharmacology, University of Bristol, Bristol, UK
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266
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French SL, Arthur JF, Tran HA, Hamilton JR. Approval of the first protease-activated receptor antagonist: Rationale, development, significance, and considerations of a novel anti-platelet agent. Blood Rev 2014; 29:179-89. [PMID: 25467961 DOI: 10.1016/j.blre.2014.10.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 10/27/2014] [Indexed: 12/12/2022]
Abstract
Twenty-three years after the discovery of the first thrombin receptor, now known as protease-activated receptor 1 (PAR1), the first drug targeting this receptor is available for human use. The PAR1 inhibitor, vorapaxar (Zontivity, MSD), was recently approved by the FDA for use in the USA for the prevention of thrombotic cardiovascular events in patients with a history of myocardial infarction or peripheral artery disease. In this review, we detail the rationale, development, as well as the clinical significance and considerations of vorapaxar, the original PAR antagonist and the latest anti-platelet agent in the pharmaco-armoury against arterial thrombosis.
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Affiliation(s)
- Shauna L French
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia; Department of Clinical Haematology, Monash University, Melbourne, Victoria, Australia
| | - Jane F Arthur
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia; Department of Clinical Haematology, Monash University, Melbourne, Victoria, Australia
| | - Huyen A Tran
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia; Department of Clinical Haematology, Monash University, Melbourne, Victoria, Australia
| | - Justin R Hamilton
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia; Department of Clinical Haematology, Monash University, Melbourne, Victoria, Australia.
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267
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Amison RT, Momi S, Morris A, Manni G, Keir S, Gresele P, Page CP, Pitchford SC. RhoA signaling through platelet P2Y₁ receptor controls leukocyte recruitment in allergic mice. J Allergy Clin Immunol 2014; 135:528-38. [PMID: 25445826 DOI: 10.1016/j.jaci.2014.09.032] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 07/21/2014] [Accepted: 09/19/2014] [Indexed: 01/09/2023]
Abstract
BACKGROUND Clinical studies reveal platelet activation in patients with asthma, allergic rhinitis, and eczema. This is distinct from platelet aggregation, which is critical for the maintenance of hemostasis and in which a role for platelet purinergic receptors is well documented. However, purines are also essential for inflammatory cell trafficking in animal models of allergic lung inflammation, which are known to be platelet dependent, yet the role of purines in the platelet activation accompanying inflammation is unknown. OBJECTIVES We investigated whether the involvement of purine activation of platelets during allergic inflammation is distinct from purine involvement in platelet aggregation. METHODS BALB/c mice were sensitized to ovalbumin and subsequent airway ovalbumin challenge. Bronchoalveolar lavage fluid was analyzed for inflammatory cells, and blood samples were assessed for platelet activation. The role of platelet purinergic receptors and associated signaling mechanisms (RhoA) were assessed. RESULTS P2Y₁, but not P2Y₁₂ or P2X₁, antagonism inhibited pulmonary leukocyte recruitment. The formation of platelet-leukocyte complexes in vivo and platelet/P-selectin-dependent polymorphonuclear cell migration in vitro were exclusively platelet P2Y₁ receptor dependent. Furthermore, platelet P2Y₁ activation resulted in RhoA activity in vivo after allergen challenge, and RhoA signaling in platelets through P2Y₁ stimulation was required for platelet-dependent leukocyte chemotaxis in vitro. Leukocyte recruitment in thrombocytopenic mice remained suppressed after reinfusion of platelets pretreated with a P2Y₁ antagonist or a Rho-associated kinase 1 inhibitor, confirming the crucial role of platelet P2Y₁ receptor and subsequent activation of RhoA. CONCLUSION RhoA signaling downstream of platelet P2Y₁, but not P2Y₁₂, represents a clear dichotomy in platelet activation during allergic inflammation versus hemostasis.
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Affiliation(s)
- Richard T Amison
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom
| | - Stefania Momi
- Department of Medicine, Section of Internal and Cardiovascular Medicine, University of Perugia, Perugia, Italy
| | - Abigail Morris
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom
| | - Giorgia Manni
- Department of Medicine, Section of Internal and Cardiovascular Medicine, University of Perugia, Perugia, Italy
| | - Sandra Keir
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom
| | - Paolo Gresele
- Department of Medicine, Section of Internal and Cardiovascular Medicine, University of Perugia, Perugia, Italy
| | - Clive P Page
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom
| | - Simon C Pitchford
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom.
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268
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In vitro evaluation of pathogen-inactivated buffy coat-derived platelet concentrates during storage: psoralen-based photochemical treatment step-by-step. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2014; 13:255-64. [PMID: 25369598 DOI: 10.2450/2014.0082-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 07/22/2014] [Indexed: 12/22/2022]
Abstract
BACKGROUND The Intercept Blood SystemTM (Cerus) is used to inactivate pathogens in platelet concentrates (PC). The aim of this study was to elucidate the extent to which the Intercept treatment modifies the functional properties of platelets. MATERIAL AND METHODS A two-arm study was conducted initially to compare buffy coat-derived pathogen-inactivated PC to untreated PC (n=5) throughout storage. A four-arm study was then designed to evaluate the contribution of the compound adsorbing device (CAD) and ultraviolet (UV) illumination to the changes observed upon Intercept treatment. Intercept-treated PC, CAD-incubated PC, and UV-illuminated PC were compared to untreated PC (n=5). Functional characteristics were assessed using flow cytometry, hypotonic shock response (HSR), aggregation, adhesion assays and flow cytometry for the detection of CD62P, CD42b, GPIIb-IIIa, phosphatidylserine exposure and JC-1 aggregates. RESULTS Compared to fresh platelets, end-of-storage platelets exhibited greater passive activation, disruption of the mitochondrial transmembrane potential (Δψm), and phosphatidylserine exposure accompanied by a decreased capacity to respond to agonist-induced aggregation, lower HSR, and CD42b expression. The Intercept treatment resulted in significantly lower HSR and CD42b expression compared to controls on day 7, with no significant changes in CD62P, Δψm, or phosphatidylserine exposure. GPIIbIIIa expression was significantly increased in Intercept-treated platelets throughout the storage period. The agonist-induced aggregation response was highly dependent on the type and concentration of agonist used, indicating a minor effect of the Intercept treatment. The CAD and UV steps alone had a negligible effect on platelet aggregation. DISCUSSION The Intercept treatment moderately affects platelet function in vitro. CAD and UV illumination alone make negligible contributions to the changes in aggregation observed in Intercept-treated PC.
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269
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Platelet mechanosensing of substrate stiffness during clot formation mediates adhesion, spreading, and activation. Proc Natl Acad Sci U S A 2014; 111:14430-5. [PMID: 25246564 DOI: 10.1073/pnas.1322917111] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
As platelets aggregate and activate at the site of vascular injury to stem bleeding, they are subjected to a myriad of biochemical and biophysical signals and cues. As clot formation ensues, platelets interact with polymerizing fibrin scaffolds, exposing platelets to a large range of mechanical microenvironments. Here, we show for the first time (to our knowledge) that platelets, which are anucleate cellular fragments, sense microenvironmental mechanical properties, such as substrate stiffness, and transduce those cues into differential biological signals. Specifically, as platelets mechanosense the stiffness of the underlying fibrin/fibrinogen substrate, increasing substrate stiffness leads to increased platelet adhesion and spreading. Importantly, adhesion on stiffer substrates also leads to higher levels of platelet activation, as measured by integrin αIIbβ3 activation, α-granule secretion, and procoagulant activity. Mechanistically, we determined that Rac1 and actomyosin activity mediate substrate stiffness-dependent platelet adhesion, spreading, and activation to different degrees. This capability of platelets to mechanosense microenvironmental cues in a growing thrombus or hemostatic plug and then mechanotransduce those cues into differential levels of platelet adhesion, spreading, and activation provides biophysical insight into the underlying mechanisms of platelet aggregation and platelet activation heterogeneity during thrombus formation.
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270
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Tsai HJ, Huang CL, Chang YW, Huang DY, Lin CC, Cooper JA, Cheng JC, Tseng CP. Disabled-2 is required for efficient hemostasis and platelet activation by thrombin in mice. Arterioscler Thromb Vasc Biol 2014; 34:2404-12. [PMID: 25212232 DOI: 10.1161/atvbaha.114.302602] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The essential role of platelet activation in hemostasis and thrombotic diseases focuses attention on unveiling the underlying intracellular signals of platelet activation. Disabled-2 (Dab2) has been implicated in platelet aggregation and in the control of clotting responses. However, there is not yet any in vivo study to provide direct evidence for the role of Dab2 in hemostasis and platelet activation. APPROACH AND RESULTS Megakaryocyte lineage-restricted Dab2 knockout (Dab2(-/-)) mice were generated to delineate in vivo functions of Dab2 in platelets. Dab2(-/-) mice appeared normal in size with prolonged bleeding time and impaired thrombus formation. Although normal in platelet production and granule biogenesis, Dab2(-/-) platelets elicited a selective defect in platelet aggregation and spreading on fibrinogen in response to low concentrations of thrombin, but not other soluble agonists. Investigation of the role of Dab2 in thrombin signaling revealed that Dab2 has no effect on the expression of thrombin receptors and the outside-in signaling. Dab2(-/-) platelets stimulated by low concentrations of thrombin were normal in Gαq-mediated calcium mobilization and protein kinase C activation, but were defective in Gα₁₂/₁₃-mediated RhoA-ROCKII activation. The attenuated Gα₁₂/₁₃ signaling led to impaired ADP release, Akt-mammalian target of rapamycin and integrin αIIbβ3 activation, fibrinogen binding, and clot retraction. The defective responses of Dab2(-/-) platelets to low concentrations of thrombin stimulation may contribute to the impaired hemostasis and thrombosis of Dab2(-/-) mice. CONCLUSIONS This study sheds new insight in platelet biology and represents the first report demonstrating that Dab2 is a key regulator of hemostasis and thrombosis by functional interplay with Gα₁₂/₁₃-mediated thrombin signaling.
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Affiliation(s)
- Hui-Ju Tsai
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Chien-Ling Huang
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yao-Wen Chang
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Ding-Yuan Huang
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Chung-Ching Lin
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Jonathan A Cooper
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Ju-Chien Cheng
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Ching-Ping Tseng
- From the Graduate Institute of Biomedical Sciences (H.-J.T., Y.-W.C., C.-P.T.), and Department of Medical Biotechnology and Laboratory Science (C.-L.H., D.-Y.H., C.-C.L., C.-P.T.), College of Medicine, Chang Gung University, Taoyuan, Taiwan; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (J.A.C.); Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (J.-C.C.); Molecular Medicine Research Center, Chang Gung University (C.-P.T.) and Department of Family Medicine (C.-P.T.), Chang Gung Memorial Hospital, Taoyuan, Taiwan.
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271
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Lee DS, Kim TH, Jung YS. Inhibitory effect of allyl isothiocyanate on platelet aggregation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:7131-7139. [PMID: 24980285 DOI: 10.1021/jf4041518] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Allyl isothiocyanate (AITC) is one of the major components of mustard. The present study for the first time attempted to evaluate the effect of AITC on platelet aggregation. In the in vitro study using platelet-rich plasma (PRP) from rats and humans, AITC at concentrations of 100 and 300 μM significantly inhibited platelet aggregation induced by collagen, thrombin, ADP, and arachidonic acid. AITC also attenuated thromboxane A2 production and ATP release in rat and human PRP. AITC elicited inhibitory effects on cellular Ca(2+) increase and platelet shape change in rat PRP. AITC further showed inhibitory effects on the phosphorylation of PKCδ, p38, ERK, and Akt in rat PRP. In the rat ex vivo study, 1 and 3 mg/kg (po) of AITC showed significant inhibitory effect on platelet aggregation. Furthermore, AITC showed a protective effect in thromboembolism attack model in mouse. These results suggest that AITC has remarkable antiplatelet effects and maybe a therapeutic potential for the prevention of aberrant platelet activation-related disorders.
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Affiliation(s)
- Do-Seop Lee
- College of Pharmacy and ‡College of Pharmacy, Research Institute of Pharmaceutical Sciences and Technology, Ajou University , Suwon 443-749, Republic of Korea
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272
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Kim M, Han CH, Lee MY. Enhancement of platelet aggregation by ursolic Acid and oleanolic Acid. Biomol Ther (Seoul) 2014; 22:254-9. [PMID: 25009707 PMCID: PMC4060080 DOI: 10.4062/biomolther.2014.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 03/17/2014] [Accepted: 03/24/2014] [Indexed: 01/05/2023] Open
Abstract
The pentacyclic triterpenoid ursolic acid (UA) and its isomer oleanolic acid (OA) are ubiquitous in food and plant medicine, and thus are easily exposed to the population through natural contact or intentional use. Although they have diverse health benefits, reported cardiovascular protective activity is contentious. In this study, the effect of UA and OA on platelet aggregation was examined on the basis that alteration of platelet activity is a potential process contributing to cardiovascular events. Treatment of UA enhanced platelet aggregation induced by thrombin or ADP, which was concentration-dependent in a range of 5-50 μM. Quite comparable results were obtained with OA, in which OA-treated platelets also exhibited an exaggerated response to either thrombin or ADP. UA treatment potentiated aggregation of whole blood, while OA failed to increase aggregation by thrombin. UA and OA did not affect plasma coagulation assessed by measuring prothrombin time and activated partial thromboplastin time. These results indicate that both UA and OA are capable of making platelets susceptible to aggregatory stimuli, and platelets rather than clotting factors are the primary target of them in proaggregatory activity. These compounds need to be used with caution, especially in the population with a predisposition to cardiovascular events.
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Affiliation(s)
- Mikyung Kim
- College of Pharmacy, Dongguk University, Goyang 410-820
| | - Chang-Ho Han
- Department of Internal Medicine, College of Korean Medicine, Dongguk University, Gyeongju 780-714, Republic of Korea
| | - Moo-Yeol Lee
- College of Pharmacy, Dongguk University, Goyang 410-820
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273
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Giordanetto F, Bach P, Zetterberg F, Antonsson T, Bylund R, Johansson J, Sellén M, Brown D, Hideståhl L, Berntsson P, Hovdal D, Zachrisson H, Björkman JA, van Giezen J. Optimization of ketone-based P2Y12 receptor antagonists as antithrombotic agents: Pharmacodynamics and receptor kinetics considerations. Bioorg Med Chem Lett 2014; 24:2963-8. [DOI: 10.1016/j.bmcl.2014.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 03/31/2014] [Accepted: 04/01/2014] [Indexed: 10/25/2022]
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274
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Pietraforte D, Vona R, Marchesi A, de Jacobis IT, Villani A, Del Principe D, Straface E. Redox control of platelet functions in physiology and pathophysiology. Antioxid Redox Signal 2014; 21:177-93. [PMID: 24597688 DOI: 10.1089/ars.2013.5532] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
SIGNIFICANCE An imbalance between the production and the detoxification of reactive oxygen species and reactive nitrogen species (ROS/RNS) can be implicated in many pathological processes. Platelets are best known as primary mediators of hemostasis and can be either targets of ROS/RNS or generate radicals during cell activation. These conditions can dramatically affect platelet physiology, leading even, as an ultimate event, to the cell number modification. In this case, pathological conditions such as thrombocytosis (promoted by increased cell number) or thrombocytopenia and myelodysplasia (promoted by cell decrease mediated by accelerated apoptosis) can occur. RECENT ADVANCES Usually, in peripheral blood, ROS/RNS production is balanced by the rate of oxidant elimination. Under this condition, platelets are in a nonadherent "resting" state. During endothelial dysfunction or under pathological conditions, ROS/RNS production increases and the platelets respond with specific biochemical and morphologic changes. Mitochondria are at the center of these processes, being able to both generate ROS/RNS, that drive redox-sensitive events, and respond to ROS/RNS-mediated changes of the cellular redox state. Irregular function of platelets and enhanced interaction with leukocytes and endothelial cells can contribute to pathogenesis of atherosclerotic and thrombotic events. CRITICAL ISSUES The relationship between oxidative stress, platelet death, and the activation-dependent pathways that drive platelet pro-coagulant activity is unclear and deserves to be explored. FUTURE DIRECTIONS Expanding knowledge about how platelets can mediate hemostasis and modulate inflammation may lead to novel and effective therapeutic strategies for the long and growing list of pathological conditions that involve both thrombosis and inflammation.
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Affiliation(s)
- Donatella Pietraforte
- 1 Department of Cell Biology and Neurosciences, Section of Cell Aging and Gender Medicine, Istituto Superiore di Sanità , Rome, Italy
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275
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Moscardó A, Vallés J, Latorre A, Santos M. The association of thromboxane A2
receptor with lipid rafts is a determinant for platelet functional responses. FEBS Lett 2014; 588:3154-9. [DOI: 10.1016/j.febslet.2014.06.057] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 06/24/2014] [Indexed: 10/25/2022]
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276
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Danese E, Montagnana M, Lippi G. Platelets and migraine. Thromb Res 2014; 134:17-22. [DOI: 10.1016/j.thromres.2014.03.055] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/31/2014] [Accepted: 03/31/2014] [Indexed: 10/25/2022]
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277
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Fuentes E, Palomo I. Regulatory mechanisms of cAMP levels as a multiple target for antiplatelet activity and less bleeding risk. Thromb Res 2014; 134:221-6. [PMID: 24830902 DOI: 10.1016/j.thromres.2014.04.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 04/22/2014] [Accepted: 04/25/2014] [Indexed: 12/19/2022]
Abstract
Platelet activation is a critical component of atherothrombosis. The multiple pathways of platelet activation limit the effect of specific receptor/pathway inhibitors, resulting in limited clinical efficacy. Recent research has confirmed that combination therapy results in enhanced antithrombotic efficacy without increasing bleeding risk. In this way, the best-known inhibitor and turn off signaling in platelet activation is cAMP. In this article we discuss the mechanisms of regulation of intraplatelet cAMP levels, a) platelet-dependent pathway: Gi/Gs protein-coupled receptors, phosphodiesterase inhibition and activation of PPARs and b) platelet-independent pathway: inhibition of adenosine uptake by erythrocytes. With respect to the association between intraplatelet cAMP levels and bleeding risk it is possible to establish that compounds/drugs with pleitropic effect for increased intraplatelet cAMP level could have an antithrombotic activity with less risk of bleeding.
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Affiliation(s)
- Eduardo Fuentes
- Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile; Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, R09I2001, Chile.
| | - Iván Palomo
- Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile; Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, R09I2001, Chile.
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278
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Daito J, Harada Y, Dai P, Yamaoka Y, Tamagawa-Mineoka R, Katoh N, Takamatsu T. Neutrophil Phagocytosis of Platelets in the Early Phase of 2,4,6-trinitro-1-chlorobenzene (TNCB)-induced Dermatitis in Mice. Acta Histochem Cytochem 2014; 47:67-74. [PMID: 25221365 PMCID: PMC4138403 DOI: 10.1267/ahc.14013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 03/03/2014] [Indexed: 01/12/2023] Open
Abstract
Activated platelets form platelet–leukocyte aggregates in the circulation in inflammatory diseases. We investigated whether activated platelets in inflamed skin tissues are phagocytized and removed by neutrophils. To investigate the kinetics of platelets and neutrophils, we immunohistochemically examined the spatiotemporal distribution of them in a murine model of 2,4,6-trinitro-1-chlorobenzene (TNCB)-induced dermatitis by using confocal and structured illumination microscopy. Four hours after elicitation, aggregates of CD41-positive platelets were adhered to CD31-positive endothelial cells within the vessels, and CD62P and PF4, markers of activated platelets, were expressed on platelet aggregates. At 8 hour post-elicitation, fragmented CD41-positive platelets were located both inside and outside vessels. Twenty-four hours after elicitation, the number of Ly-6G-positive neutrophils ingesting fragmented CD41-positive platelets outside vessels was increased, and CD62P and PF4 expression on the phagocytosed platelets was no longer observed. Disc-shaped CD41-positive platelets were not found outside vessels at any time during the experiment. Our data revealed that aggregates of activated platelets inside vessels were ingested and removed by neutrophils in the early stage of TNCB-induced dermatitis, suggesting that the process of removal of activated platelets by neutrophils may play an important role not only in the early phase of skin inflammation but also in other types of acute inflammation.
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Affiliation(s)
- Junko Daito
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine
- Department of Dermatology, Kyoto Prefectural University of Medicine
| | - Yoshinori Harada
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine
| | - Ping Dai
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine
| | - Yoshihisa Yamaoka
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine
| | | | - Norito Katoh
- Department of Dermatology, Kyoto Prefectural University of Medicine
| | - Tetsuro Takamatsu
- Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine
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279
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Wang X, Jiang W, Li F, Hua F, Zhan Y, Li Y, Ji L, Zou S, Min Z, Song D, Cheng Y. Abnormal platelet kinetics are detected before the occurrence of thrombocytopaenia in HBV-related liver disease. Liver Int 2014; 34:535-43. [PMID: 24612171 DOI: 10.1111/liv.12309] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 08/10/2013] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Thrombocytopaenia is a frequent feature in patients with HBV-related liver disease. Its underlying mechanism is not fully understood. Multiple factors might contribute to the development of thrombocytopaenia. In this study, we investigated the reticulated platelets (RP), glycocalicin (GC), serum thrombopoietin (TPO) and platelet glycoprotein (GP) in different stages of the disease. METHODS One hundred and fourteen patients with HBV-related liver disease (30 with chronic hepatitis B (CHB), 20 patients in Child A without thrombocytopaenia, 19 patients in Child A with thrombocytopaenia, 45 in Child B/C with thrombocytopaenia) and 25 normal controls (NC) were enrolled. Liver cirrhosis (LC) was classified according to modified Child-Turcotte-Pugh (CTP) score. Serum TPO levels and GC were measured by ELISA. RP and platelet glycoprotein (GP) expression were detected by flow cytometry. RESULTS The TPO levels of patients with LC were significantly lower than that of controls, even in patients of Child A without thrombocytopaenia group. Serum TPO level was positively correlated (r = 0.65, p < 0.01) with serum albumin in Child B/C group. Both the RP percentages and the glycocalicin index (GCI) levels were significantly higher in patients groups including CHB and Child A without thrombocytopaenia than that of normal controls. A negative correlation existed in HBV DNA copies and the GPs% in patients with CHB and Child A without thrombocytopaenia. CONCLUSION Abnormal platelet production, destruction and platelet-specific glycoproteins levels were detected before the occurrence of thrombocytopaenia in HBV-related liver disease, indicating that multiple mechanisms might play roles in thrombocytopaenia in HBV-infected patients.
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Affiliation(s)
- Xiaoyun Wang
- Department of Hematology, Zhongshan Hospital, Fudan University, Shanghai, China; Department of Gastroenterology, Wuxi Second People's Hospital, Jiangsu Province, China; Department of Gastroenterology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
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280
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Prudent M, D’Alessandro A, Cazenave JP, Devine DV, Gachet C, Greinacher A, Lion N, Schubert P, Steil L, Thiele T, Tissot JD, Völker U, Zolla L. Proteome Changes in Platelets After Pathogen Inactivation—An Interlaboratory Consensus. Transfus Med Rev 2014; 28:72-83. [DOI: 10.1016/j.tmrv.2014.02.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 01/31/2014] [Accepted: 02/07/2014] [Indexed: 12/21/2022]
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281
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Lopez-Vilchez I, Serra-Millas M, Navarro V, Rosa Hernandez M, Villalta J, Diaz-Ricart M, Gasto C, Escolar G, Galan AM. Prothrombotic platelet phenotype in major depression: downregulation by antidepressant treatment. J Affect Disord 2014; 159:39-45. [PMID: 24679387 DOI: 10.1016/j.jad.2014.02.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/10/2014] [Accepted: 02/12/2014] [Indexed: 12/16/2022]
Abstract
BACKGROUND Serotonergic mechanisms have been suggested as a link between major depression and cardiovascular risk. We investigated the existence of a prothrombotic condition in depressed patients and its possible modulation during treatment with a selective serotonin-reuptake inhibitor (SSRI). METHODS Modifications in a series of biomarkers of platelet and coagulation activation were evaluated in blood from 19 patients with a major depression disorder (MDD) at the time of diagnosis, and at 8 and 24 weeks of treatment with escitalopram. Response of blood aliquots recirculated through a thrombogenic surface was assessed in a thrombosis model. Results were compared with those of 20 healthy-matched controls. RESULTS In comparison with controls, platelets from MDD patients showed elevated volumes (p<0.01), significantly enhanced aggregating response to arachidonic acid and augmented expression of GPIb, fibrinogen, factor V, and anionic phospholipids by flow cytometry (p<0.05). Clot firmness and procoagulant activity of platelet-associated tissue factor were also significantly elevated (p<0.05). Studies with circulating blood revealed increased fibrin formation in early diagnosed patients (71.1±9.5% vs. 45.8±5.3%; p<0.05 vs. controls). After 24 weeks of treatment with escitalopram, the majority of the alterations observed were normalized, except for a residual increased expression of GPIIbIIIa (p<0.05) and persistent alterations in thromboelatometic parameters. LIMITATIONS Despite the reduced number of followed-up patients our findings were consistent reaching statistical significance. CONCLUSIONS Our results reveal a prothrombotic phenotype in MDD patients. While continuous treatment with an SSRI downregulated the majority of the biomarkers analyzed, alterations in viscoelastic parameters of clot formation remained unaffected by the antidepressant treatment.
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Affiliation(s)
- Irene Lopez-Vilchez
- Department of Hemotherapy and Hemostasis, Hospital Clinic, Biomedical Diagnosis Centre, Institute of Biomedical Research August Pi i Sunyer, University of Barcelona, Barcelona, Spain.
| | - Montserrat Serra-Millas
- Department of Psychiatry, Hospital Clinic, Institute Clinic of Neurosciences, Barcelona, Spain
| | - Victor Navarro
- Department of Psychiatry, Hospital Clinic, Institute Clinic of Neurosciences, Barcelona, Spain
| | - M Rosa Hernandez
- Department of Hemotherapy and Hemostasis, Hospital Clinic, Biomedical Diagnosis Centre, Institute of Biomedical Research August Pi i Sunyer, University of Barcelona, Barcelona, Spain
| | - Jaume Villalta
- Department of Internal Medicine, Hospital Clinic, Barcelona, Spain
| | - Maribel Diaz-Ricart
- Department of Hemotherapy and Hemostasis, Hospital Clinic, Biomedical Diagnosis Centre, Institute of Biomedical Research August Pi i Sunyer, University of Barcelona, Barcelona, Spain
| | - Cristobal Gasto
- Department of Psychiatry, Hospital Clinic, Institute Clinic of Neurosciences, Barcelona, Spain
| | - Gines Escolar
- Department of Hemotherapy and Hemostasis, Hospital Clinic, Biomedical Diagnosis Centre, Institute of Biomedical Research August Pi i Sunyer, University of Barcelona, Barcelona, Spain
| | - Ana M Galan
- Department of Hemotherapy and Hemostasis, Hospital Clinic, Biomedical Diagnosis Centre, Institute of Biomedical Research August Pi i Sunyer, University of Barcelona, Barcelona, Spain
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282
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Akrawinthawong K, Park JW, Piknova B, Sibmooh N, Fucharoen S, Schechter AN. A flow cytometric analysis of the inhibition of platelet reactivity due to nitrite reduction by deoxygenated erythrocytes. PLoS One 2014; 9:e92435. [PMID: 24642865 PMCID: PMC3958531 DOI: 10.1371/journal.pone.0092435] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 02/21/2014] [Indexed: 11/18/2022] Open
Abstract
Nitric oxide (NO), a small gas molecule, has long been known to be a potent inhibitor of platelet function but the physiological and pathological implications of platelet inhibition by NO have not been well clarified. We recently showed that the addition of nitrite to platelet-rich plasma in the presence of erythrocytes could inhibit platelet aggregation and this inhibitory effect of nitrite + erythrocytes was enhanced by deoxygenation of erythrocytes as measured by P-selectin expression and cGMP production. In order to study the nitrite effect on platelets at different oxygen levels, we used the flow cytometric assays to detect platelet membrane surface markers upon activation. The P-selectin and activated gpIIb/IIIa expression on platelet membranes in response to ADP, collagen and thrombin stimulation was measured at various hematocrit and oxygen levels. Nitrite (0.1 to 1.0 μM) significantly decreased the percentage of these surface markers on the platelet membrane at the hematocrit values above 23% and oxygen levels lower than 49 mmHg. The inhibitory effect of nitrite was augmented by increasing hematocrit values and decreasing oxygen saturation. C-PTIO (an NO scavenger) prevented the platelet inhibition by nitrite + erythrocytes whereas the inhibitors of NO synthase and xanthine oxidoreductase had no effect. These results support the proposal that circulating nitrite decreases platelet reactivity in the presence of partially deoxygenated erythrocytes through its reduction to NO, which may also explain certain differences between arterial and venous thrombosis and support directly the role of deoxyhemoglobin in this process. We believe that our flow cytometric assays offer a possibility to identify the individual molecular process involved in these effects.
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Affiliation(s)
- Krittapoom Akrawinthawong
- Molecular Medicine Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of Biochemistry, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Ji Won Park
- Molecular Medicine Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Barbora Piknova
- Molecular Medicine Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Nathawut Sibmooh
- Department of Pharmacology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Suthat Fucharoen
- Thalassemia Research Center, Institute of Science and Technology for Research and Development, Mahidol University, Nakhonpathom, Thailand
| | - Alan N. Schechter
- Molecular Medicine Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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283
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Secor D, Swarbreck S, Ellis CG, Sharpe MD, Tyml K. Ascorbate reduces mouse platelet aggregation and surface P-selectin expression in an ex vivo model of sepsis. Microcirculation 2014; 20:502-10. [PMID: 23402318 DOI: 10.1111/micc.12047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 02/05/2013] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Compromised perfusion of the capillary bed can lead to organ failure and mortality in sepsis. We have reported that intravenous injection of ascorbate inhibits platelet adhesion and plugging in septic capillaries. In this study, we hypothesized that ascorbate reduces aggregation of platelets and their surface expression of P-selectin (a key adhesion molecule) in mice. METHODS Platelets were isolated from control mice and subjected to agents known to be released into the bloodstream during sepsis (thrombin, ADP or U46619, thromboxane A2 analog). Platelet aggregation was analyzed by aggregometry and P-selectin expression by flow cytometry. RESULTS Platelet-activating agents increased aggregation and P-selectin expression. Ascorbate inhibited these increases. This inhibitory effect was NOS-independent (LNAME had no effect). In contrast to the platelet-activating agents, direct stimuli lipopolysaccharide, TNFα, or plasma from septic mice did not increase aggregation/expression, a finding consistent with the literature. The results suggest a complex mechanism of platelet aggregation and P-selectin expression in sepsis, where generation of platelet-activating stimuli is required first, before platelet aggregation and adhesion in capillaries occur. CONCLUSION The ability of ascorbate to reduce platelet aggregation and P-selectin expression could be an important mechanism by which ascorbate inhibits capillary plugging in sepsis.
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Affiliation(s)
- Dan Secor
- Critical Illness Research, Lawson Health Research Institute, London, Ontario, Canada
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284
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Overview of platelet physiology: its hemostatic and nonhemostatic role in disease pathogenesis. ScientificWorldJournal 2014; 2014:781857. [PMID: 24729754 PMCID: PMC3960550 DOI: 10.1155/2014/781857] [Citation(s) in RCA: 203] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Accepted: 11/10/2013] [Indexed: 12/23/2022] Open
Abstract
Platelets are small anucleate cell fragments that circulate in blood playing crucial role in managing vascular integrity and regulating hemostasis. Platelets are also involved in the fundamental biological process of chronic inflammation associated with disease pathology. Platelet indices like mean platelets volume (MPV), platelets distributed width (PDW), and platelet crit (PCT) are useful as cheap noninvasive biomarkers for assessing the diseased states. Dynamic platelets bear distinct morphology, where α and dense granule are actively involved in secretion of molecules like GPIIb , IIIa, fibrinogen, vWf, catecholamines, serotonin, calcium, ATP, ADP, and so forth, which are involved in aggregation. Differential expressions of surface receptors like CD36, CD41, CD61 and so forth have also been quantitated in several diseases. Platelet clinical research faces challenges due to the vulnerable nature of platelet structure functions and lack of accurate assay techniques. But recent advancement in flow cytometry inputs huge progress in the field of platelets study. Platelets activation and dysfunction have been implicated in diabetes, renal diseases, tumorigenesis, Alzheimer's, and CVD. In conclusion, this paper elucidates that platelets are not that innocent as they keep showing and thus numerous novel platelet biomarkers are upcoming very soon in the field of clinical research which can be important for predicting and diagnosing disease state.
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285
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Ibelli AMG, Kim TK, Hill CC, Lewis LA, Bakshi M, Miller S, Porter L, Mulenga A. A blood meal-induced Ixodes scapularis tick saliva serpin inhibits trypsin and thrombin, and interferes with platelet aggregation and blood clotting. Int J Parasitol 2014; 44:369-79. [PMID: 24583183 DOI: 10.1016/j.ijpara.2014.01.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/29/2013] [Accepted: 01/06/2014] [Indexed: 01/22/2023]
Abstract
Ixodes scapularis is a medically important tick species that transmits causative agents of important human tick-borne diseases including borreliosis, anaplasmosis and babesiosis. An understanding of how this tick feeds is needed prior to the development of novel methods to protect the human population against tick-borne disease infections. This study characterizes a blood meal-induced I. scapularis (Ixsc) tick saliva serine protease inhibitor (serpin (S)), in-house referred to as IxscS-1E1. The hypothesis that ticks use serpins to evade the host's defense response to tick feeding is based on the assumption that tick serpins inhibit functions of protease mediators of the host's anti-tick defense response. Thus, it is significant that consistent with hallmark characteristics of inhibitory serpins, Pichia pastoris-expressed recombinant IxscS-1E1 (rIxscS-1E1) can trap thrombin and trypsin in SDS- and heat-stable complexes, and reduce the activity of the two proteases in a dose-responsive manner. Additionally, rIxscS-1E1 also inhibited, but did not apparently form detectable complexes with, cathepsin G and factor Xa. Our data also show that rIxscS-1E1 may not inhibit chymotrypsin, kallikrein, chymase, plasmin, elastase and papain even at a much higher rIxscS-1E1 concentration. Native IxscS-1E1 potentially plays a role(s) in facilitating I. scapularis tick evasion of the host's hemostatic defense as revealed by the ability of rIxscS-1E1 to inhibit adenosine diphosphate- and thrombin-activated platelet aggregation, and delay activated partial prothrombin time and thrombin time plasma clotting in a dose-responsive manner. We conclude that native IxscS-1E1 is part of the tick saliva protein complex that mediates its anti-hemostatic, and potentially inflammatory, functions by inhibiting the actions of thrombin, trypsin and other yet unknown trypsin-like proteases at the tick-host interface.
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Affiliation(s)
- Adriana M G Ibelli
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA; Federal University of São Carlos, Graduate Program in Genetics and Evolution, Brazil
| | - Tae K Kim
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA
| | - Creston C Hill
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA
| | - Lauren A Lewis
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA
| | - Mariam Bakshi
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA
| | - Stephanie Miller
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA; College Station High School, Science Department-Biology, 4002 Victoria Ave, College Station, TX 77845, USA
| | - Lindsay Porter
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA
| | - Albert Mulenga
- Texas A & M University AgriLife Research, Department of Entomology, 2475 TAMU, College Station, TX 77843, USA.
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286
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Fälker K, Klarström-Engström K, Bengtsson T, Lindahl TL, Grenegård M. The Toll-like receptor 2/1 (TLR2/1) complex initiates human platelet activation via the src/Syk/LAT/PLCγ2 signalling cascade. Cell Signal 2014; 26:279-86. [DOI: 10.1016/j.cellsig.2013.11.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 11/06/2013] [Indexed: 11/16/2022]
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287
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Involvement of neutrophils in thrombus formation in living mice. ACTA ACUST UNITED AC 2014; 62:1-9. [PMID: 24485849 DOI: 10.1016/j.patbio.2013.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 11/12/2013] [Indexed: 12/24/2022]
Abstract
Thrombosis is one of the major causes of human death worldwide. Identification of the cellular and molecular mechanisms leading to thrombus formation is thus crucial for the understanding of the thrombotic process. To examine thrombus formation in a living mouse, new technologies have been developed. Digital intravital microscopy allows to visualize the development of thrombosis and generation of fibrin in real-time within living animal in a physiological context. This specific system allowed the identification of new cellular partners involved in platelet adhesion and activation. Furthermore, it improved, especially, the knowledge of the early phase of thrombus formation and fibrin generation in vivo. Until now, platelets used to be considered the sole central player in thrombus generation. However, recently, it has been demonstrated that leukocytes, particularly neutrophils, play a crucial role in the activation of the blood coagulation cascade leading to thrombosis. In this review, we summarized the mechanisms leading to thrombus formation in the microcirculation according to the method of injury in mice with a special focus on the new identified roles of neutrophils in this process.
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288
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Tsai JC, Lin YW, Huang CY, Lin CY, Tsai YT, Shih CM, Lee CY, Chen YH, Li CY, Chang NC, Lin FY, Tsai CS. The role of calpain-myosin 9-Rab7b pathway in mediating the expression of Toll-like receptor 4 in platelets: a novel mechanism involved in α-granules trafficking. PLoS One 2014; 9:e85833. [PMID: 24489676 PMCID: PMC3904858 DOI: 10.1371/journal.pone.0085833] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 12/02/2013] [Indexed: 01/26/2023] Open
Abstract
Toll-like receptors (TLRs) plays a critical role in innate immunity. In 2004, Aslam R. and Shiraki R. first determined that murine and human platelets express functional TLRs. Additionally, Andonegui G. demonstrated that platelets express TLR4, which contributes to thrombocytopenia. However, the underlying mechanisms of TLR4 expression by platelets have been rarely explored until now. The aim of this study was to identify the mechanism of TLR4 expression underlying thrombin treatment. The human washed platelets were used in this study. According to flowcytometry and western blot analysis, the surface levels of TLR4 were significantly enhanced in thrombin-activated human platelets and decreased by TMB-8, calpeptin, and U73122, but not Y27632 (a Rho-associated protein kinase ROCK inhibitor) indicating that thrombin-mediated TLR4 expression was modulated by PAR/PLC pathway, calcium and calpain. Co-immunoprecipitation (co-IP) assay demonstrated that the interaction between TLR4 and myosin-9 (a substrate of calpain) was regulated by calpain; cleavage of myosin-9 enhanced TLR4 expression in thrombin treated platelets. Transmission electron microscope data indicated that human platelets used α-granules to control TLR4 expression; the co-IP experiment suggested that myosin-9 did not coordinate with Rab7b to negatively regulate TLR4 trafficking in thrombin treated platelets. In summary, phospholipase Cγ-calpain-myosin 9-Rab7b axis was responsible for the mechanism underlying the regulation of TLR4 containing α-granules trafficking in thrombin-stimulated platelets, which was involved in coagulation.
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Affiliation(s)
- Jui-Chi Tsai
- Graduate Institute of Medical Sciences, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
- Departments of Internal Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yi-Wen Lin
- Division of Cardiovascular Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Chun-Yao Huang
- Departments of Internal Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology and Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chih-Yuan Lin
- Division of Cardiovascular Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Yi-Ting Tsai
- Division of Cardiovascular Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Chun-Min Shih
- Departments of Internal Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology and Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chung-Yi Lee
- Division of Cardiovascular Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Yung-Hsiang Chen
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
| | - Chi-Yuan Li
- Graduate Institute of Clinical Medical Sciences, China Medical University, Taichung, Taiwan
- Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan
| | - Nen-Chung Chang
- Departments of Internal Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology and Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Feng-Yen Lin
- Departments of Internal Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology and Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
- * E-mail: (FYL); (CST)
| | - Chien-Sung Tsai
- Division of Cardiovascular Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
- * E-mail: (FYL); (CST)
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Palmer TD, Martínez CH, Vasquez C, Hebron KE, Jones-Paris C, Arnold SA, Chan SM, Chalasani V, Gomez-Lemus JA, Williams AK, Chin JL, Giannico GA, Ketova T, Lewis JD, Zijlstra A. Integrin-free tetraspanin CD151 can inhibit tumor cell motility upon clustering and is a clinical indicator of prostate cancer progression. Cancer Res 2014; 74:173-87. [PMID: 24220242 PMCID: PMC3947299 DOI: 10.1158/0008-5472.can-13-0275] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Normal physiology relies on the organization of transmembrane proteins by molecular scaffolds, such as tetraspanins. Oncogenesis frequently involves changes in their organization or expression. The tetraspanin CD151 is thought to contribute to cancer progression through direct interaction with the laminin-binding integrins α3β1 and α6β1. However, this interaction cannot explain the ability of CD151 to control migration in the absence of these integrins or on non-laminin substrates. We demonstrate that CD151 can regulate tumor cell migration without direct integrin binding and that integrin-free CD151 (CD151(free)) correlates clinically with tumor progression and metastasis. Clustering CD151(free) through its integrin-binding domain promotes accumulation in areas of cell-cell contact, leading to enhanced adhesion and inhibition of tumor cell motility in vitro and in vivo. CD151(free) clustering is a strong regulator of motility even in the absence of α3 expression but requires PKCα, suggesting that CD151 can control migration independent of its integrin associations. The histologic detection of CD151(free) in prostate cancer correlates with poor patient outcome. When CD151(free) is present, patients are more likely to recur after radical prostatectomy and progression to metastatic disease is accelerated. Multivariable analysis identifies CD151(free) as an independent predictor of survival. Moreover, the detection of CD151(free) can stratify survival among patients with elevated prostate-specific antigen levels. Cumulatively, these studies demonstrate that a subpopulation of CD151 exists on the surface of tumor cells that can regulate migration independent of its integrin partner. The clinical correlation of CD151(free) with prostate cancer progression suggests that it may contribute to the disease and predict cancer progression.
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Affiliation(s)
- Trenis D Palmer
- Authors' Affiliations:Departments of Pathology, Microbiology and Immunology and Cancer Biology, Vanderbilt University, Nashville, Tennessee; Department of Oncology, University of Alberta, Edmonton, Alberta; Translational Prostate Cancer Research Group, London Regional Cancer Program; and Department of Pathology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario Canada
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290
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Fuentes E, Caballero J, Alarcón M, Rojas A, Palomo I. Chlorogenic acid inhibits human platelet activation and thrombus formation. PLoS One 2014; 9:e90699. [PMID: 24598787 PMCID: PMC3944540 DOI: 10.1371/journal.pone.0090699] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 02/04/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Chlorogenic acid is a potent phenolic antioxidant. However, its effect on platelet aggregation, a critical factor in arterial thrombosis, remains unclear. Consequently, chlorogenic acid-action mechanisms in preventing platelet activation and thrombus formation were examined. METHODS AND RESULTS Chlorogenic acid in a dose-dependent manner (0.1 to 1 mmol/L) inhibited platelet secretion and aggregation induced by ADP, collagen, arachidonic acid and TRAP-6, and diminished platelet firm adhesion/aggregation and platelet-leukocyte interactions under flow conditions. At these concentrations chlorogenic acid significantly decreased platelet inflammatory mediators (sP-selectin, sCD40L, CCL5 and IL-1β) and increased intraplatelet cAMP levels/PKA activation. Interestingly, SQ22536 (an adenylate cyclase inhibitor) and ZM241385 (a potent A2A receptor antagonist) attenuated the antiplatelet effect of chlorogenic acid. Chlorogenic acid is compatible to the active site of the adenosine A2A receptor as revealed through molecular modeling. In addition, chlorogenic acid had a significantly lower effect on mouse bleeding time when compared to the same dose of aspirin. CONCLUSIONS Antiplatelet and antithrombotic effects of chlorogenic acid are associated with the A2A receptor/adenylate cyclase/cAMP/PKA signaling pathway.
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Affiliation(s)
- Eduardo Fuentes
- Department of Clinical Biochemistry and Immunohematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile
- Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, Talca, Chile
- * E-mail: (IP); (EF)
| | - Julio Caballero
- Center for Bioinformatics and Molecular Simulations, Faculty of Engineering in Bioinformatics, Universidad de Talca, Talca, Chile
| | - Marcelo Alarcón
- Department of Clinical Biochemistry and Immunohematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile
- Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, Talca, Chile
| | - Armando Rojas
- Biomedical Research Laboratories, Medicine Faculty, Catholic University of Maule, Talca, Chile
| | - Iván Palomo
- Department of Clinical Biochemistry and Immunohematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile
- Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, Talca, Chile
- * E-mail: (IP); (EF)
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292
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Albright RA, Ornstein DL, Cao W, Chang WC, Robert D, Tehan M, Hoyer D, Liu L, Stabach P, Yang G, De La Cruz EM, Braddock DT. Molecular basis of purinergic signal metabolism by ectonucleotide pyrophosphatase/phosphodiesterases 4 and 1 and implications in stroke. J Biol Chem 2013; 289:3294-306. [PMID: 24338010 DOI: 10.1074/jbc.m113.505867] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
NPP4 is a type I extracellular membrane protein on brain vascular endothelium inducing platelet aggregation via the hydrolysis of Ap3A, whereas NPP1 is a type II extracellular membrane protein principally present on the surface of chondrocytes that regulates tissue mineralization. To understand the metabolism of purinergic signals resulting in the physiologic activities of the two enzymes, we report the high resolution crystal structure of human NPP4 and explore the molecular basis of its substrate specificity with NPP1. Both enzymes cleave Ap3A, but only NPP1 can hydrolyze ATP. Comparative structural analysis reveals a tripartite lysine claw in NPP1 that stabilizes the terminal phosphate of ATP, whereas the corresponding region of NPP4 contains features that hinder this binding orientation, thereby inhibiting ATP hydrolysis. Furthermore, we show that NPP1 is unable to induce platelet aggregation at physiologic concentrations reported in human blood, but it could stimulate platelet aggregation if localized at low nanomolar concentrations on vascular endothelium. The combined studies expand our understanding of NPP1 and NPP4 substrate specificity and range and provide a rational mechanism by which polymorphisms in NPP1 confer stroke resistance.
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Affiliation(s)
- Ronald A Albright
- From the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
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293
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Zhou X, Zheng Y. Cell type-specific signaling function of RhoA GTPase: lessons from mouse gene targeting. J Biol Chem 2013; 288:36179-88. [PMID: 24202176 DOI: 10.1074/jbc.r113.515486] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
RhoA GTPase is a key intracellular regulator of actomyosin dynamics and other cell functions, including adhesion, proliferation, survival, and gene expression. Most of our knowledge of RhoA signaling function is from studies in immortalized cell lines utilizing inhibitors or dominant mutant overexpression, both of which are limited in terms of specificity, dosage, and clonal variation. Recent mouse gene targeting studies of rhoA and its regulators/effectors have revealed cell type-specific signaling mechanisms in the context of mammalian physiology. The new knowledge may present therapeutic opportunities for the rational targeting of RhoA signaling-mediated pathophysiologies.
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Affiliation(s)
- Xuan Zhou
- From the Division of Experimental Hematology and Cancer Biology, Children's Hospital Research Foundation, University of Cincinnati, Cincinnati, Ohio 45229
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294
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Zhou Q, Jiang L, Xu C, Luo D, Zeng C, Liu P, Yue M, Liu Y, Hu X, Hu H. Ginsenoside Rg1 inhibits platelet activation and arterial thrombosis. Thromb Res 2013; 133:57-65. [PMID: 24196231 DOI: 10.1016/j.thromres.2013.10.032] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 10/19/2013] [Accepted: 10/20/2013] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Derived from the root of Panax ginseng C.A.Mey, Panax notoginsenosides (PNS) is a widely used herbal medicine to treat atherothrombotic diseases in Asian medicine. Ginsenoside Rg1 is one of the main compounds responsible for the pharmaceutical actions of PNS. As platelets play pivotal roles in atherothrombogenesis, we therefore studied the effect of Rg1 on platelet activation and its underlying mechanisms. MATERIALS AND METHODS Human platelets are obtained from healthy subjects. Platelet activation and the inhibition of Rg1 were assessed by Born aggregometer, flow cytmetry, flow chamber and western blot. The in vivo thrombosis model was induced by 10% FeCl3 on mesenteric arterioles of wild type B57/b6 mice. RESULTS Rg1 significantly inhibited platelet aggregation induced by thrombin, ADP, collagen and U46619, e.g., aggregation rate stimulated by 0.1UmL(-1) thrombin was decreased 46% by Rg1. Rg1 also reduced thrombin (0.1UmL(-1))-enhanced fibrinogen binding and P-selectin expression of single platelet by 81% and 66%, respectively. Rg1 affected αIIbβ3-mediated outside-in signaling as demonstrated by diminished platelet spreading on immobilized fibrinogen. Rg1 also decreased the rate of clot retraction in platelet rich plasma. Furthermore, Rg1 decreased platelet adhesion on collagen surface under a shear rate correlated to the arterial flow (1000s(-1)) by approximately 70%. Western blot showed that Rg1 potently inhibited ERK phosphrylation. The in vitro findings were further evaluated in the mouse model of in vivo arterial thrombosis, and Rg1 was found to prolong the mesenteric arterial occlusion time (34.9±4.1min without and 64.3±4.9min with Rg1; p<0.01). CONCLUSIONS Rg1 inhibits platelet activation via the inhibition of ERK pathway, and attenuates arterial thrombus formation in vivo.
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Affiliation(s)
- Qi Zhou
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Lei Jiang
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Chunhua Xu
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Dongjiao Luo
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Chunlai Zeng
- Department of Cardiology, Lishui Central Hospital, Lishui, China
| | - Pu Liu
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Ming Yue
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Yangyang Liu
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaosheng Hu
- Department of Cardiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hu Hu
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou, China.
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295
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Study of molecular mechanism of Prostaglandin E1 in inhibiting coronary heart disease. Mol Biol Rep 2013; 40:6701-8. [PMID: 24146100 DOI: 10.1007/s11033-013-2785-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 09/14/2013] [Indexed: 01/28/2023]
Abstract
Prostaglandin E1 has been used clinically for improving heart diseases. In this study, we examined the effect of Prostaglandin E1 on blood lipid levels, heart protein and genes expression in coronary heart disease (CHD) rats. Female rats were fed either a control diet or hypercholesterolemic diet for 14 weeks. The feeding of a hypercholesterolemic diet (HCD) increased the serum TC, TG, and LDL-c levels, decreased the serum HDL-c, E2, P, FSH, LH and PRL levels in CHD rats. In addition, The feeding of a HCD diet markedly increased the content of serum TXA2, TXB2, and decreased the content of serum PGI2, and PGI2/TXA2, 6-Keto PGF1a. Furthermore, the feeding of a hypercholesterolemic diet markedly increased expression levels of myocardium Fas and Caspase-3 protein and mRNA levels, vascular endothelial growth factor and basic fibroblast growth factor mRNA, and decreased RyR2 mRNA in CHD rats. The feeding of Prostaglandin E1 for 14 weeks significantly reversed these abnormal biochemical indexes in rats. These findings suggest that Prostaglandin E1 play a obvious heart protective effect. The mechanisms may be related to restraining the excessive activation of Fas and Caspase-3 protein and modulating some gene expressions associated with CHD.
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296
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Fälker K, Nazare M, Wonerow P, Kozian DH. Targeting Platelet G Protein-Coupled Receptors for Antithrombotic Therapy. Drug Dev Res 2013. [DOI: 10.1002/ddr.21101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Knut Fälker
- Department of Biomedicine; School of Health and Medical Sciences; Örebro University; 70182; Örebro; Sweden
| | - Marc Nazare
- Leibniz Institute for Molecular Pharmacology (FMP); Robert-Rössle-Strasse 10; 13125; Berlin; Germany
| | - Peter Wonerow
- Sanofi-Aventis Deutschland GmbH; Industriepark Hoechst; 65926; Frankfurt; Germany
| | - Detlef H. Kozian
- Sanofi-Aventis Deutschland GmbH; Industriepark Hoechst; 65926; Frankfurt; Germany
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297
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Capranzano P, Angiolillo DJ. Basics of Antithrombotic Therapy for Cardiovascular Disease: Pharmacologic Targets of Platelet Inhibitors and Anticoagulants. Interv Cardiol Clin 2013; 2:499-513. [PMID: 28582179 DOI: 10.1016/j.iccl.2013.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Arterial thrombus formation is the common pathophysiologic process of cardiovascular disease manifestations, requiring interplay between platelets and coagulation factors. Current platelet inhibitors block the formation of thromboxane A2 and interfer with adenosine diphosphate stimulation mediated by the P2Y12 receptor. Novel antiplatelet agents blocking these and other pathways are under clinical development. Thrombin represents a bridge between platelets and coagulation. Indirect and direct thrombin inhibitors are pivotal in clinical settings. Other key coagulation factors include factors IX and X which are therapeutic targets of current and novel anticoagulants. This article reviews the pathophysiology of arterial thrombosis and current and novel antiplatelet and anticoagulant agents.
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Affiliation(s)
- Piera Capranzano
- Cardiovascular Department, Ferrarotto Hospital, University of Catania, Citelli 1, Catania 95124, Italy
| | - Dominick J Angiolillo
- Division of Cardiology, Department of Medicine, Shands Jacksonville, University of Florida College of Medicine-Jacksonville, 655 West 8th Street, Jacksonville, FL 32209, USA.
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298
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Shishehbor MH, Katzen BT. Antithrombotic Strategies in Endovascular Interventions: Current Status and Future Directions. Interv Cardiol Clin 2013; 2:627-633. [PMID: 28582189 DOI: 10.1016/j.iccl.2013.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Despite increasing numbers of endovascular interventions to treat arterial and venous disease, scant level 1 evidence is available regarding the role of antithrombotic and antiplatelet therapy in patients undergoing these procedures. The current practice in this regard is heterogeneous and has mainly been driven by data from coronary artery disease and percutaneous coronary intervention. This article discusses the role of antithrombotic and antiplatelet agents for endovascular intervention.
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Affiliation(s)
- Mehdi H Shishehbor
- Endovascular Services, Heart & Vascular Institute, Cleveland Clinic, 9500 Euclid Avenue, J3-05, Cleveland, OH 44195, USA.
| | - Barry T Katzen
- Baptist Cardiac & Vascular Institute, 8900 North Kendall Drive, Miami, FL 33176, USA
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299
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Abstract
Platelets are anucleated fragments produced by megakaryocytes that circulate in the blood. Platelets are involved in the initial cellular response to damaged endothelium and migrate to this area to prevent excessive bleeding. What is becoming more acknowledged over the last few decades is that blood flow (hemodynamics) plays a critical role in platelet function. The purpose of this review is to summarize the current understanding of platelet biology with particular focus on the role of hemodynamics. The emerging concept of shear microgradients, which are challenging the traditional model of platelet function, will also be introduced in the review.
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Affiliation(s)
- Angus Ka Tsun Wong
- Australian Centre for Blood Diseases, 6th Floor, Burnet Tower, 89 Commercial Rd., Melbourne, VIC 3004, Australia.
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300
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Highly electronegative LDL from patients with ST-elevation myocardial infarction triggers platelet activation and aggregation. Blood 2013; 122:3632-41. [PMID: 24030386 DOI: 10.1182/blood-2013-05-504639] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Platelet activation and aggregation underlie acute thrombosis that leads to ST-elevation myocardial infarction (STEMI). L5-highly electronegative low-density lipoprotein (LDL)-is significantly elevated in patients with STEMI. Thus, we examined the role of L5 in thrombogenesis. Plasma LDL from patients with STEMI (n = 30) was chromatographically resolved into 5 subfractions (L1-L5) with increasing electronegativity. In vitro, L5 enhanced adenosine diphosphate-stimulated platelet aggregation twofold more than did L1 and induced platelet-endothelial cell (EC) adhesion. L5 also increased P-selectin expression and glycoprotein (GP)IIb/IIIa activation and decreased cyclic adenosine monophosphate levels (n = 6, P < .01) in platelets. In vivo, injection of L5 (5 mg/kg) into C57BL/6 mice twice weekly for 6 weeks shortened tail bleeding time by 43% (n = 3; P < .01 vs L1-injected mice) and increased P-selectin expression and GPIIb/IIIa activation in platelets. Pharmacologic blockade experiments revealed that L5 signals through platelet-activating factor receptor and lectin-like oxidized LDL receptor-1 to attenuate Akt activation and trigger granule release and GPIIb/IIIa activation via protein kinase C-α. L5 but not L1 induced tissue factor and P-selectin expression in human aortic ECs (P < .01), thereby triggering platelet activation and aggregation with activated ECs. These findings indicate that elevated plasma levels of L5 may promote thrombosis that leads to STEMI.
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