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Khalil JS, Law R, Raslan Z, Cheah LT, Hindle MS, Aburima AA, Kearney MT, Naseem KM. Protein Kinase A Regulates Platelet Phosphodiesterase 3A through an A-Kinase Anchoring Protein Dependent Manner. Cells 2024; 13:1104. [PMID: 38994957 PMCID: PMC11240354 DOI: 10.3390/cells13131104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 06/14/2024] [Accepted: 06/21/2024] [Indexed: 07/13/2024] Open
Abstract
Platelet activation is critical for haemostasis, but if unregulated can lead to pathological thrombosis. Endogenous platelet inhibitory mechanisms are mediated by prostacyclin (PGI2)-stimulated cAMP signalling, which is regulated by phosphodiesterase 3A (PDE3A). However, spatiotemporal regulation of PDE3A activity in platelets is unknown. Here, we report that platelets possess multiple PDE3A isoforms with seemingly identical molecular weights (100 kDa). One isoform contained a unique N-terminal sequence that corresponded to PDE3A1 in nucleated cells but with negligible contribution to overall PDE3A activity. The predominant cytosolic PDE3A isoform did not possess the unique N-terminal sequence and accounted for >99% of basal PDE3A activity. PGI2 treatment induced a dose and time-dependent increase in PDE3A phosphorylation which was PKA-dependent and associated with an increase in phosphodiesterase enzymatic activity. The effects of PGI2 on PDE3A were modulated by A-kinase anchoring protein (AKAP) disruptor peptides, suggesting an AKAP-mediated PDE3A signalosome. We identified AKAP7, AKAP9, AKAP12, AKAP13, and moesin expressed in platelets but focussed on AKAP7 as a potential PDE3A binding partner. Using a combination of immunoprecipitation, proximity ligation techniques, and activity assays, we identified a novel PDE3A/PKA RII/AKAP7 signalosome in platelets that integrates propagation and termination of cAMP signalling through coupling of PKA and PDE3A.
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Affiliation(s)
- Jawad S. Khalil
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK; (J.S.K.); (Z.R.); (L.T.C.); (M.S.H.); (M.T.K.)
| | - Robert Law
- Hull York Medical School, University of Hull, Hull HU6 7EL, UK; (R.L.); (A.A.A.)
| | - Zaher Raslan
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK; (J.S.K.); (Z.R.); (L.T.C.); (M.S.H.); (M.T.K.)
| | - Lih T. Cheah
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK; (J.S.K.); (Z.R.); (L.T.C.); (M.S.H.); (M.T.K.)
| | - Matthew S. Hindle
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK; (J.S.K.); (Z.R.); (L.T.C.); (M.S.H.); (M.T.K.)
| | - Ahmed A. Aburima
- Hull York Medical School, University of Hull, Hull HU6 7EL, UK; (R.L.); (A.A.A.)
| | - Mark T. Kearney
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK; (J.S.K.); (Z.R.); (L.T.C.); (M.S.H.); (M.T.K.)
| | - Khalid M. Naseem
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK; (J.S.K.); (Z.R.); (L.T.C.); (M.S.H.); (M.T.K.)
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2
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Provenzale I, Solari FA, Schönichen C, Brouns SLN, Fernández DI, Kuijpers MJE, van der Meijden PEJ, Gibbins JM, Sickmann A, Jones C, Heemskerk JWM. Endothelium-mediated regulation of platelet activation: Involvement of multiple protein kinases. FASEB J 2024; 38:e23468. [PMID: 38334433 DOI: 10.1096/fj.202300360rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 01/11/2024] [Accepted: 01/23/2024] [Indexed: 02/10/2024]
Abstract
The endothelial regulation of platelet activity is incompletely understood. Here we describe novel approaches to find molecular pathways implicated on the platelet-endothelium interaction. Using high-shear whole-blood microfluidics, employing coagulant or non-coagulant conditions at physiological temperature, we observed that the presence of human umbilical vein endothelial cells (HUVEC) strongly suppressed platelet adhesion and activation, via the collagen receptor glycoprotein VI (GPVI) and the PAR receptors for thrombin. Real-time monitoring of the cytosolic Ca2+ rises in the platelets indicated no major improvement of inhibition by prostacyclin or nitric oxide. Similarly under stasis, exposure of isolated platelets to HUVEC reduced the Ca2+ responses by collagen-related peptide (CRP-XL, GPVI agonist) and thrombin (PAR agonist). We then analyzed the label-free phosphoproteome of platelets (three donors), exposed to HUVEC, CRP-XL, and/or thrombin. High-resolution mass spectrometry gave 5463 phosphopeptides, corresponding to 1472 proteins, with good correlation between biological and technical replicates (R > .86). Stringent filtering steps revealed 26 regulatory pathways (Reactome) and 143 regulated kinase substrates (PhosphoSitePlus), giving a set of protein phosphorylation sites that was differentially (44) or similarly (110) regulated by HUVEC or agonist exposure. The differential regulation was confirmed by stable-isotope analysis of platelets from two additional donors. Substrate analysis indicated major roles of poorly studied protein kinase classes (MAPK, CDK, DYRK, STK, PKC members). Collectively, these results reveal a resetting of the protein phosphorylation profile in platelets exposed to endothelium or to conventional agonists and to endothelium-promoted activity of a multi-kinase network, beyond classical prostacyclin and nitric oxide actors, that may contribute to platelet inhibition.
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Affiliation(s)
- Isabella Provenzale
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Institute for Cardiovascular and Metabolic Research (ICMR), School of Biological Sciences, University of Reading, Reading, UK
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Dortmund, Germany
| | - Fiorella A Solari
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Dortmund, Germany
| | - Claudia Schönichen
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Center for Thrombosis and Haemostasis, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sanne L N Brouns
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Delia I Fernández
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Marijke J E Kuijpers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Thrombosis Expertise Center, Heart and Vascular Center, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Paola E J van der Meijden
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Thrombosis Expertise Center, Heart and Vascular Center, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Jonathan M Gibbins
- Institute for Cardiovascular and Metabolic Research (ICMR), School of Biological Sciences, University of Reading, Reading, UK
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Dortmund, Germany
- Medizinische Fakultät, Medizinische Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
- Department of Chemistry, College of Physical Sciences, University of Aberdeen, Aberdeen, UK
| | - Chris Jones
- Institute for Cardiovascular and Metabolic Research (ICMR), School of Biological Sciences, University of Reading, Reading, UK
| | - Johan W M Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Synapse Research Institute Maastricht, Maastricht, The Netherlands
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3
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Noce D, Foco L, Orth-Höller D, König E, Barbieri G, Pietzner M, Ghasemi-Semeskandeh D, Coassin S, Fuchsberger C, Gögele M, Del Greco M F, De Grandi A, Summerer M, Wheeler E, Langenberg C, Lass-Flörl C, Pramstaller PP, Kronenberg F, Würzner R, Pattaro C. Genetic determinants of complement activation in the general population. Cell Rep 2024; 43:113611. [PMID: 38159276 DOI: 10.1016/j.celrep.2023.113611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 09/08/2023] [Accepted: 12/07/2023] [Indexed: 01/03/2024] Open
Abstract
Complement is a fundamental innate immune response component. Its alterations are associated with severe systemic diseases. To illuminate the complement's genetic underpinnings, we conduct genome-wide association studies of the functional activity of the classical (CP), lectin (LP), and alternative (AP) complement pathways in the Cooperative Health Research in South Tyrol study (n = 4,990). We identify seven loci, encompassing 13 independent, pathway-specific variants located in or near complement genes (CFHR4, C7, C2, MBL2) and non-complement genes (PDE3A, TNXB, ABO), explaining up to 74% of complement pathways' genetic heritability and implicating long-range haplotypes associated with LP at MBL2. Two-sample Mendelian randomization analyses, supported by transcriptome- and proteome-wide colocalization, confirm known causal pathways, establish within-complement feedback loops, and implicate causality of ABO on LP and of CFHR2 and C7 on AP. LP causally influences collectin-11 and KAAG1 levels and the risk of mouth ulcers. These results build a comprehensive resource to investigate the role of complement in human health.
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Affiliation(s)
- Damia Noce
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy; Institute of Hygiene & Medical Microbiology, Department of Hygiene, Microbiology and Public Health, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria
| | - Luisa Foco
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Dorothea Orth-Höller
- Institute of Hygiene & Medical Microbiology, Department of Hygiene, Microbiology and Public Health, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria; MB-LAB - Clinical Microbiology Laboratory, Franz-Fischer-Str. 7b, 6020 Innsbruck, Austria
| | - Eva König
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Giulia Barbieri
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy; Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Maik Pietzner
- Computational Medicine, Berlin Institute of Health (BIH) at Charité - Universitätsmedizin Berlin, Berlin, Germany; MRC Epidemiology Unit, University of Cambridge, Cambridge, UK
| | - Dariush Ghasemi-Semeskandeh
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy; Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Stefan Coassin
- Institute of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria
| | - Christian Fuchsberger
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Martin Gögele
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Fabiola Del Greco M
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Alessandro De Grandi
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Monika Summerer
- Institute of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria
| | - Eleanor Wheeler
- MRC Epidemiology Unit, University of Cambridge, Cambridge, UK
| | - Claudia Langenberg
- Computational Medicine, Berlin Institute of Health (BIH) at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Cornelia Lass-Flörl
- Institute of Hygiene & Medical Microbiology, Department of Hygiene, Microbiology and Public Health, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria
| | - Peter Paul Pramstaller
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy
| | - Florian Kronenberg
- Institute of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria.
| | - Reinhard Würzner
- Institute of Hygiene & Medical Microbiology, Department of Hygiene, Microbiology and Public Health, Medical University of Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria.
| | - Cristian Pattaro
- Institute for Biomedicine (affiliated to the University of Lübeck), Eurac Research, Via Volta 21, 39100 Bolzano, Italy.
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4
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Reimann MJ, Faisst DN, Knold M, Meurs KM, Stern JA, Cremer SE, Møller JE, Ljungvall I, Häggström J, Olsen LH. No impact of polymorphism in the phosphodiesterase 5A gene in Cavalier King Charles Spaniels on pimobendan-induced inhibition of platelet aggregation response. J Vet Intern Med 2023; 37:2145-2156. [PMID: 37743723 PMCID: PMC10658480 DOI: 10.1111/jvim.16871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 09/08/2023] [Indexed: 09/26/2023] Open
Abstract
BACKGROUND A variant in the canine phosphodiesterase (PDE) 5A gene (PDE5A:E90K) is associated with decreased concentrations of circulating cyclic guanosine monophosphate (cGMP) and response to PDE5 inhibitor treatment. Pimobendan is a PDE inhibitor recommended for medical treatment of certain stages of myxomatous mitral valve disease (MMVD) in dogs. HYPOTHESIS PDE5A:E90K polymorphism attenuates the inhibitory effect of pimobendan on in vitro platelet aggregation and increases basal platelet aggregation in Cavalier King Charles Spaniels (CKCS). Selected clinical variables (MMVD severity, sex, age, hematocrit, platelet count in platelet-rich plasma [PRP], and echocardiographic left ventricular fractional shortening [LV FS]) will not show an association with results. ANIMALS Fifty-two privately owned CKCS with no or preclinical MMVD. METHODS Using blood samples, we prospectively assessed PDE5A genotype using Sanger sequencing and adenosine diphosphate-induced platelet aggregation response (area under the curve [AUC], maximal aggregation [MaxA], and velocity [Vel]) with and without pimobendan using light transmission aggregometry. Dogs also underwent echocardiography. RESULTS Pimobendan inhibited platelet function as measured by AUC, MaxA, and Vel at a concentration of 10 μM (P < .0001) and Vel at 0.03 μM (P < .001). PDE5A:E90K polymorphism did not influence the inhibitory effect of pimobendan or basal platelet aggregation response. CONCLUSIONS AND CLINICAL IMPORTANCE The PDE5A:E90K polymorphism did not influence in vitro basal platelet aggregation response or the inhibitory effect of pimobendan on platelet aggregation in CKCS. Dogs with the PDE5A:E90K polymorphism did not appear to have altered platelet function or response to pimobendan treatment.
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Affiliation(s)
- Maria J. Reimann
- Department of Veterinary and Animal SciencesUniversity of CopenhagenFrederiksbergDenmark
| | - Daniel N. Faisst
- Department of Veterinary and Animal SciencesUniversity of CopenhagenFrederiksbergDenmark
| | - Mads Knold
- Department of Veterinary and Animal SciencesUniversity of CopenhagenFrederiksbergDenmark
| | - Kathryn M. Meurs
- Department of Clinical SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
| | - Joshua A. Stern
- Department of Medicine and Epidemiology, School of Veterinary MedicineUniversity of California‐DavisDavisCaliforniaUSA
| | - Signe E. Cremer
- Department of Veterinary Clinical SciencesUniversity of CopenhagenFrederiksbergDenmark
| | - Jacob E. Møller
- Department of CardiologyCopenhagen University Hospital RigshospitaletCopenhagenDenmark
| | - Ingrid Ljungvall
- Department of Clinical SciencesSwedish University of Agricultural SciencesUppsalaSweden
| | - Jens Häggström
- Department of Clinical SciencesSwedish University of Agricultural SciencesUppsalaSweden
| | - Lisbeth H. Olsen
- Department of Veterinary and Animal SciencesUniversity of CopenhagenFrederiksbergDenmark
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5
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Gawaz M, Geisler T, Borst O. Current concepts and novel targets for antiplatelet therapy. Nat Rev Cardiol 2023; 20:583-599. [PMID: 37016032 DOI: 10.1038/s41569-023-00854-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/27/2023] [Indexed: 04/06/2023]
Abstract
Platelets have a crucial role in haemostasis and atherothrombosis. Pharmacological control of platelet hyper-reactivity has become a cornerstone in the prevention of thrombo-ischaemic complications in atherosclerotic diseases. Current antiplatelet therapies substantially improve clinical outcomes in patients with coronary artery disease, but at the cost of increased risk of bleeding. Beyond their role in thrombosis, platelets are known to regulate inflammatory (thrombo-inflammatory) and microcirculatory pathways. Therefore, controlling platelet hyper-reactivity might have implications for both tissue inflammation (myocardial ischaemia) and vascular inflammation (vulnerable plaque formation) to prevent atherosclerosis. In this Review, we summarize the pathophysiological role of platelets in acute myocardial ischaemia, vascular inflammation and atherosclerotic progression. Furthermore, we highlight current clinical concepts of antiplatelet therapy that have contributed to improving patient care and have facilitated more individualized therapy. Finally, we discuss novel therapeutic targets and compounds for antiplatelet therapy that are currently in preclinical development, some of which have a more favourable safety profile than currently approved drugs with regard to bleeding risk. These novel antiplatelet targets might offer new strategies to treat cardiovascular disease.
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Affiliation(s)
- Meinrad Gawaz
- Department of Cardiology and Angiology, Eberhard Karls University of Tübingen, Tübingen, Germany.
| | - Tobias Geisler
- Department of Cardiology and Angiology, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Oliver Borst
- Department of Cardiology and Angiology, Eberhard Karls University of Tübingen, Tübingen, Germany
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6
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Gui X, Chu X, Du Y, Wang Y, Zhang S, Ding Y, Tong H, Xu M, Li Y, Ju W, Sun Z, Li Z, Zeng L, Xu K, Qiao J. Impaired Platelet Function and Thrombus Formation in PDE5A-Deficient Mice. Thromb Haemost 2023; 123:207-218. [PMID: 36252813 DOI: 10.1055/a-1962-1613] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Intracellular cyclic GMP (cGMP) inhibits platelet function. Platelet cGMP levels are controlled by phosphodiesterase 5A (PDE5A)-mediated degradation. However, the exact role of PDE5A in platelet function and thrombus formation remains poorly understood. In this study, we characterized the role of PDE5A in platelet activation and function. Platelets were isolated from wild type or PDE5A-/- mice to measure platelet aggregation, activation, phosphatidylserine exposure (annexin-V binding), reactive oxygen species (ROS) generation, platelet spreading as well as clot retraction. Cytosolic calcium mobilization was measured using Fluo-4 AM by a microplate reader. Western blot was used to measure the phosphorylation of VASP, ERK1/2, p38, JNK, and AKT. FeCl3-induced arterial thrombosis and venous thrombosis were assessed to evaluate the in vivo hemostatic function and thrombus formation. Additionally, in vitro thrombus formation was assessed in a microfluidic whole-blood perfusion assay. PDE5A-deficient mice presented significantly prolonged tail bleeding time and delayed arterial and venous thrombus formation. PDE5A deficiency significantly inhibited platelet aggregation, ATP release, P-selectin expression, and integrin aIIbb3 activation. In addition, an impaired spreading on collagen or fibrinogen and clot retraction was observed in PDE5A-deficient platelets. Moreover, PDE5A deficiency reduced phosphatidylserine exposure, calcium mobilization, ROS production, and increased intracellular cGMP level along with elevated VASP phosphorylation and reduced phosphorylation of ERK1/2, p38, JNK, and AKT. In conclusion, PDE5A modulates platelet activation and function and thrombus formation, indicating that therapeutically targeting it might be beneficial for the treatment of thrombotic diseases.
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Affiliation(s)
- Xiang Gui
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Xiang Chu
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Yuwei Du
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Yuhan Wang
- School of Medical Technology, Xuzhou Medical University, Xuzhou, People's Republic of China
| | - Sixuan Zhang
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Yangyang Ding
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Huan Tong
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Mengdi Xu
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Yue Li
- School of Medical Technology, Xuzhou Medical University, Xuzhou, People's Republic of China
| | - Wen Ju
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Zengtian Sun
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Zhenyu Li
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Lingyu Zeng
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China.,School of Medical Technology, Xuzhou Medical University, Xuzhou, People's Republic of China
| | - Kailin Xu
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
| | - Jianlin Qiao
- Blood Diseases Institute, Xuzhou Medical University, Xuzhou, People's Republic of China.,Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China.,Key Laboratory of Bone Marrow Stem Cell, Jiangsu Province, Xuzhou, People's Republic of China
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7
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More than reverting tyrosine kinases. Blood 2022; 140:939-941. [PMID: 36048474 DOI: 10.1182/blood.2022017208] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 06/04/2022] [Indexed: 11/02/2022] Open
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8
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Yoshida H, Itoh S, Ferdousi F, Isoda H. Post-stroke treatment with K-134, a phosphodiesterase 3 inhibitor, improves stroke outcomes in the stroke-prone spontaneously hypertensive rat model-A comparative evaluation of antiplatelet drugs. J Pharmacol Sci 2022; 148:229-237. [PMID: 35063138 DOI: 10.1016/j.jphs.2021.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/14/2021] [Accepted: 12/02/2021] [Indexed: 11/17/2022] Open
Abstract
Post-stroke antiplatelet therapy has been proved to reduce the risk of recurrent stroke; however, it may also increase the incidence of intracranial hemorrhage that could offset any benefits. Therefore, the balance between the benefits and risks of antiplatelet drugs is a critical issue to consider. In the present study, we have compared the effects of post-stroke administration of antiplatelet agents on functional outcomes in the stroke-prone spontaneously hypertensive rat (SHRSP), an established animal model that mimics human lacunar stroke and cerebral small vessel disease. We confirmed that a potent phosphodiesterase 3 (PDE3) inhibitor, K-134, significantly improved post-stroke survival rate and survival time, attenuated stroke-induced neurological deficits, and decreased the incidence of cerebral lesion caused by intracerebral hemorrhage and softening. Similarly, cilostazol showed beneficial effects, though to a lower extent with respect to the survival outcome and neurological symptoms. On the other hand, a P2Y12 inhibitor, clopidogrel significantly improved survival outcomes at the higher dose but caused massive bleeding in the brain at both low and high doses. In contrast, no hemorrhagic lesion was observed in K-134-treated SHRSPs despite its antiplatelet activity. Our findings indicate that K-134 may have a superior post-stroke therapeutic outcome in comparison to other antiplatelet drugs.
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Affiliation(s)
- Hideo Yoshida
- Tokyo New Drug Research Laboratories, Kowa Company, Ltd., Tokyo, Japan; Graduate School of Science and Technology, University of Tsukuba, Tsukuba, Ibaraki, Japan.
| | - Shinsuke Itoh
- Tokyo New Drug Research Laboratories, Kowa Company, Ltd., Tokyo, Japan
| | - Farhana Ferdousi
- Alliance for Research on the Mediterranean and North Africa (ARENA), University of Tsukuba, Tsukuba, Ibaraki, Japan; AIST-University of Tsukuba Open Innovation Laboratory for Food and Medicinal Resource Engineering (FoodMed-OIL), University of Tsukuba, Tsukuba, Japan; Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Hiroko Isoda
- Alliance for Research on the Mediterranean and North Africa (ARENA), University of Tsukuba, Tsukuba, Ibaraki, Japan; AIST-University of Tsukuba Open Innovation Laboratory for Food and Medicinal Resource Engineering (FoodMed-OIL), University of Tsukuba, Tsukuba, Japan; Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
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9
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Fernández DI, Provenzale I, Cheung HY, van Groningen J, Tullemans BM, Veninga A, Dunster JL, Honarnejad S, van den Hurk H, Kuijpers MJ, Heemskerk JW. Ultra-high-throughput Ca 2+ assay in platelets to distinguish ITAM-linked and G-protein-coupled receptor activation. iScience 2022; 25:103718. [PMID: 35072010 PMCID: PMC8762394 DOI: 10.1016/j.isci.2021.103718] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 11/12/2021] [Accepted: 12/29/2021] [Indexed: 12/30/2022] Open
Abstract
Antiplatelet drugs targeting G-protein-coupled receptors (GPCRs), used for the secondary prevention of arterial thrombosis, coincide with an increased bleeding risk. Targeting ITAM-linked receptors, such as the collagen receptor glycoprotein VI (GPVI), is expected to provide a better antithrombotic-hemostatic profile. Here, we developed and characterized an ultra-high-throughput (UHT) method based on intracellular [Ca2+]i increases to differentiate GPVI and GPCR effects on platelets. In 96-, 384-, or 1,536-well formats, Calcium-6-loaded human platelets displayed a slow-prolonged or fast-transient [Ca2+]i increase when stimulated with the GPVI agonist collagen-related peptide or with thrombin and other GPCR agonists, respectively. Semi-automated curve fitting revealed five parameters describing the Ca2+ responses. Verification of the UHT assay was done with a robustness compound library and clinically relevant platelet inhibitors. Taken together, these results present proof of principle of distinct receptor-type-dependent Ca2+ signaling curves in platelets, which allow identification of new inhibitors in a UHT way.
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Affiliation(s)
- Delia I. Fernández
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Isabella Provenzale
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- Institute for Cardiovascular and Metabolic Research, University of Reading, RG6 6AX Reading, UK
| | - Hilaire Y.F. Cheung
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- ISASLeibniz-Institut fur Analytische Wissenschaften-ISAS-e.V., 44227 Dortmund, Germany
- Institute of Cardiovascular Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | | | - Bibian M.E. Tullemans
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Alicia Veninga
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Joanne L. Dunster
- Institute for Cardiovascular and Metabolic Research, University of Reading, RG6 6AX Reading, UK
| | | | | | - Marijke J.E. Kuijpers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- Thrombosis Expertise Centre, Heart and Vascular Centre, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Johan W.M. Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- Synapse Research Institute, Kon. Emmaplein 7, 6214 AC, Maastricht, the Netherlands
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Lee CY, Wu TC, Lin SJ. Effects of Postoperative Percutaneous Coronary Intervention, Pharmacologic Treatment, and Predisposing Factors on Clinical Outcomes in Patients With and Without Type 2 Diabetes Along With Critical Limb Ischemia. Clin Ther 2020; 43:195-210.e2. [PMID: 33358255 DOI: 10.1016/j.clinthera.2020.11.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/29/2020] [Accepted: 11/22/2020] [Indexed: 12/16/2022]
Abstract
PURPOSE Critical limb ischemia (CLI) has been identified as being connected to rates of cardiovascular mortality and lower extremity amputation (LEA). This prospective study investigated the effects of percutaneous coronary intervention (PCI), pharmacologic treatment, and predisposing factors on clinical outcomes in patients with and without type 2 diabetes mellitus (DM) along with CLI after endovascular intervention. METHODS 249 consecutive patients with CLI (Fontaine stages III-IV) received pharmacologic treatment after successful endovascular intervention. Their primary patency rates of infrapopliteal lesions and cardiovascular and amputation events during a 36-month follow-up period were assessed. FINDINGS Patients with DM were more likely to be younger (P = 0.026); 50% (n = 63), 42.9% (n = 54), 52.4% (n = 66), and 77% (n = 97) of DM patients had arterial calcification, end-stage renal disease, diabetic neuropathy, and Fontaine stage IV (P < 0.001, P < 0.001, P < 0.001, and P = 0.019, respectively). The primary patency rates were 61%, 48.8%, and 42.3% at 12, 24, and 36 months, in the patients without DM (P = 0.034, P = 0.013, and P = 0.005). Patients with DM had higher risks of 36-month coronary artery disease, cerebrovascular accident, mortality, and LEA (P = 0.005, P = 0.042, P = 0.042, and P < 0.001). Patients with CLI receiving long-term cilostazol treatment had a better primary patency and amputation-free survival, and a lower risk of mortality at 36 months (P < 0.001, P < 0.001, and P = 0.001). Statin use was associated with 36-month amputation-free survival but not with primary patency (P = 0.032 and P = 0.088). Subgroup multivariate Cox analyses showed that primary patency was independently associated with long-term cilostazol treatment, PCI in the first postoperative year, and direct revascularization in the DM group, whereas in the control group, long-term cilostazol treatment was the main independent factor. The risk of amputation was independently associated with a high high-sensitivity chronic reactive protein level, diabetic neuropathy, sole use of an oral hypoglycemic agent, and lack of supervised exercise. IMPLICATIONS Long-term cilostazol treatment, aggressive management of dyslipidemia, and meticulous assessment and prevention of postoperative unstable coronary artery disease should be considered in CLI patients with and without DM to maximize clinical outcomes. PCI in the first postoperative year may be a predisposing factor for patency failure in patients with CLI, especially those with DM. A large-scale prospective randomized trial should be conducted to confirm these findings (TVGH IRB No. 2013-08-020B).
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Affiliation(s)
- Chiu-Yang Lee
- Division of Cardiovascular Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei City, Taiwan; Institute of Clinical Medicine, School of Medicine, National Yang Ming University, Taipei, Taiwan.
| | - Tao-Cheng Wu
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Shing-Jong Lin
- Institute of Clinical Medicine, School of Medicine, National Yang Ming University, Taipei, Taiwan; Taipei Heart Institute, Taipei Medical University, Taipei, Taiwan; Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan.
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11
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Impaired iloprost-induced platelet inhibition and phosphoproteome changes in patients with confirmed pseudohypoparathyroidism type Ia, linked to genetic mutations in GNAS. Sci Rep 2020; 10:11389. [PMID: 32647264 PMCID: PMC7347634 DOI: 10.1038/s41598-020-68379-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 06/22/2020] [Indexed: 11/16/2022] Open
Abstract
Patients diagnosed with pseudohypoparathyroidism type Ia (PHP Ia) suffer from hormonal resistance and abnormal postural features, in a condition classified as Albright hereditary osteodystrophy (AHO) syndrome. This syndrome is linked to a maternally inherited mutation in the GNAS complex locus, encoding for the GTPase subunit Gsα. Here, we investigated how platelet phenotype and omics analysis can assist in the often difficult diagnosis. By coupling to the IP receptor, Gsα induces platelet inhibition via adenylyl cyclase and cAMP-dependent protein kinase A (PKA). In platelets from seven patients with suspected AHO, one of the largest cohorts examined, we studied the PKA-induced phenotypic changes. Five patients with a confirmed GNAS mutation, displayed impairments in Gsα-dependent VASP phosphorylation, aggregation, and microfluidic thrombus formation. Analysis of the platelet phosphoproteome revealed 2,516 phosphorylation sites, of which 453 were regulated by Gsα-PKA. Common changes in the patients were: (1) a joint panel of upregulated and downregulated phosphopeptides; (2) overall PKA dependency of the upregulated phosphopeptides; (3) links to key platelet function pathways. In one patient with GNAS mutation, diagnosed as non-AHO, the changes in platelet phosphoproteome were reversed. This combined approach thus revealed multiple phenotypic and molecular biomarkers to assist in the diagnosis of suspected PHP Ia.
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12
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Therapeutic opportunities in colon cancer: Focus on phosphodiesterase inhibitors. Life Sci 2019; 230:150-161. [PMID: 31125564 DOI: 10.1016/j.lfs.2019.05.043] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/16/2019] [Accepted: 05/16/2019] [Indexed: 02/08/2023]
Abstract
Despite novel technologies, colon cancer remains undiagnosed and 25% of patients are diagnosed with metastatic colon cancer. Resistant to chemotherapeutic agents is one of the major problems associated with treating colon cancer which creates the need to develop novel agents targeting towards newer targets. A phosphodiesterase is a group of isoenzyme, which, hydrolyze cyclic nucleotides and thereby lowers intracellular levels of cAMP and cGMP leading to tumorigenic effects. Many in vitro and in vivo studies have confirmed increased PDE expression in different types of cancers including colon cancer. cAMP-specific PDE inhibitors increase intracellular cAMP that leads to activation of effector molecules-cAMP-dependent protein kinase A, exchange protein activated by cAMP and cAMP gated ion channels. These molecules regulate cellular responses and exert its anticancer role through different mechanisms including apoptosis, inhibition of angiogenesis, upregulating tumor suppressor genes and suppressing oncogenes. On the other hand, cGMP specific PDE inhibitors exhibit anticancer effects through cGMP dependent protein kinase and cGMP dependent cation channels. Elevation in cGMP works through activation of caspases, suppression of Wnt/b-catenin pathway and TCF transcription leading to inhibition of CDK and survivin. These studies point out towards the fact that PDE inhibition is associated with anti-proliferative, anti-apoptotic and anti-angiogenic pathways involved in its anticancer effects in colon cancer. Thus, inhibition of PDE enzymes can be used as a novel approach to treat colon cancer. This review will focus on cAMP and cGMP signaling pathways leading to tumorigenesis and the use of PDE inhibitors in colon cancer.
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14
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Makhoul S, Walter E, Pagel O, Walter U, Sickmann A, Gambaryan S, Smolenski A, Zahedi RP, Jurk K. Effects of the NO/soluble guanylate cyclase/cGMP system on the functions of human platelets. Nitric Oxide 2018; 76:71-80. [PMID: 29550521 DOI: 10.1016/j.niox.2018.03.008] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 03/03/2018] [Accepted: 03/12/2018] [Indexed: 02/07/2023]
Abstract
Platelets are circulating sentinels of vascular integrity and are activated, inhibited, or modulated by multiple hormones, vasoactive substances or drugs. Endothelium- or drug-derived NO strongly inhibits platelet activation via activation of the soluble guanylate cyclase (sGC) and cGMP elevation, often in synergy with cAMP-elevation by prostacyclin. However, the molecular mechanisms and diversity of cGMP effects in platelets are poorly understood and sometimes controversial. Recently, we established the quantitative human platelet proteome, the iloprost/prostacyclin/cAMP/protein kinase A (PKA)-regulated phosphoproteome, and the interactions of the ADP- and iloprost/prostacyclin-affected phosphoproteome. We also showed that the sGC stimulator riociguat is in vitro a highly specific inhibitor, via cGMP, of various functions of human platelets. Here, we review the regulatory role of the cGMP/protein kinase G (PKG) system in human platelet function, and our current approaches to establish and analyze the phosphoproteome after selective stimulation of the sGC/cGMP pathway by NO donors and riociguat. Present data indicate an extensive and diverse NO/riociguat/cGMP phosphoproteome, which has to be compared with the cAMP phosphoproteome. In particular, sGC/cGMP-regulated phosphorylation of many membrane proteins, G-proteins and their regulators, signaling molecules, protein kinases, and proteins involved in Ca2+ regulation, suggests that the sGC/cGMP system targets multiple signaling networks rather than a limited number of PKG substrate proteins.
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Affiliation(s)
- Stephanie Makhoul
- University Medical Center Mainz, Center for Thrombosis and Hemostasis (CTH), Mainz, Germany
| | - Elena Walter
- University Medical Center Mainz, Center for Thrombosis and Hemostasis (CTH), Mainz, Germany
| | - Oliver Pagel
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e. V., Dortmund, Germany
| | - Ulrich Walter
- University Medical Center Mainz, Center for Thrombosis and Hemostasis (CTH), Mainz, Germany
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e. V., Dortmund, Germany; Ruhr Universität Bochum, Medizinisches Proteom Center, Medizinische Fakultät, Bochum, Germany; Department of Chemistry, College of Physical Sciences, University of Aberdeen, Aberdeen, UK
| | - Stepan Gambaryan
- University Medical Center Mainz, Center for Thrombosis and Hemostasis (CTH), Mainz, Germany; Russian Academy of Sciences, Sechenov Institute of Evolutionary Physiology and Biochemistry, St. Petersburg, Russia; St. Petersburg State University, Department of Cytology and Histology, St. Petersburg, Russia
| | - Albert Smolenski
- Conway Institute of Biomolecular & Biomedical Research, Univ. College Dublin, Dublin, Ireland; Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - René P Zahedi
- Gerald Bronfman Department of Oncology, Jewish General Hospital, McGill University , Montreal, Quebec H4A 3T2, Canada; Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University , Montreal, Quebec H3T 1E2, Canada
| | - Kerstin Jurk
- University Medical Center Mainz, Center for Thrombosis and Hemostasis (CTH), Mainz, Germany.
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Galyfos G, Sianou A. Cilostazol for Secondary Prevention of Stroke: Should the Guidelines Perhaps Be Extended? Vasc Specialist Int 2017; 33:89-92. [PMID: 28955697 PMCID: PMC5614376 DOI: 10.5758/vsi.2017.33.3.89] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 06/25/2017] [Accepted: 06/27/2017] [Indexed: 12/31/2022] Open
Abstract
Cilostazol belongs to the new generation antiplatelet agents that have been introduced and studied regarding a potential role in cardiovascular disease prevention or treatment. Although data on peripheral artery disease are sufficient, and the drug has been recommended as first line treatment for intermittent claudication, it has not been approved nor recommended as far as cerebrovascular events are concerned. However, a great volume of randomized as well as pooled data has been published during the last years. Therefore, this review aims to describe the basic mechanisms of cilostazol’s action as well as to present all recent clinical data in order to conclude on whether official guidelines should be extended.
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Affiliation(s)
- George Galyfos
- Division of Vascular Surgery, Department of Propaedeutic Surgery, University of Athens Medical School, Hippocration Hospital, Athens, Greece
| | - Argyri Sianou
- Department of Microbiology, University of Athens Medical School, Areteion Hospital, Athens, Greece
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16
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Rahman K, Lowe GM, Smith S. Aged Garlic Extract Inhibits Human Platelet Aggregation by Altering Intracellular Signaling and Platelet Shape Change. J Nutr 2016; 146:410S-415S. [PMID: 26764324 DOI: 10.3945/jn.114.202408] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 03/30/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Increased platelet aggregation plays a pivotal role in the etiology of cardiovascular disease. Upon platelet aggregation, an increase in free cytoplasmic Ca(2+) results in the inhibition of soluble guanylyl cyclase (sGC) and adenylyl cyclase (AC), leading to a decrease in cyclic guaninosine-5'-monophosphate (cGMP) and cAMP, respectively. This leads to the activation of the glycoprotein IIb/IIIa (GPIIb/IIIa) fibrinogen receptor, resulting in platelet shape change. Aged garlic extract (AGE) decreases platelet aggregation; however, the mechanisms involved are not clearly defined. OBJECTIVE Our objective was to investigate the effects of AGE on intraplatelet cell signaling and platelet shape change. METHODS Platelets from 14 participants were studied. Platelet aggregation was induced by ADP in the presence of AGE up to a concentration of 6.25% (vol:vol) alone or in combination with 3-morpholinosydnonimine (Sin-1), a nitric oxide donor. The experiments with AGE were repeated in the presence of 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor. In a series of separate experiments, platelet aggregation was induced in the presence of either 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), an sGC inhibitor, or 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22536), an AC inhibitor, or a combination of both in the presence of IBMX and AGE. Intraplatelet cGMP and cAMP were measured. The platelets were also subjected to scanning electron microscopic analysis, and their binding to fibrinogen was determined. RESULTS AGE decreased platelet aggregation at all concentrations tested; this decrease was more marked in the presence of Sin-1 and ranged between 15% and 67%.The presence of IBMX also led to a decrease (17-35%) in platelet aggregation at all AGE concentrations and a significant decrease in the amounts of cGMP (24-41%) and cAMP (19-70%), respectively, in the presence of ODQ and SQ22536. The presence of AGE significantly inhibited the binding of activated platelets to fibrinogen, preventing changes in platelet shape. CONCLUSION These results indicate that AGE inhibits platelet aggregation by increasing cyclic nucleotides and inhibiting fibrinogen binding and platelet shape change.
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Affiliation(s)
- Khalid Rahman
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Gordon M Lowe
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Sarah Smith
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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17
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Galyfos G, Geropapas G, Sigala F, Aggeli K, Sianou A, Filis K. Meta-Analysis of Studies Evaluating the Effect of Cilostazol on Major Outcomes After Carotid Stenting. J Endovasc Ther 2015; 23:186-95. [PMID: 26620397 DOI: 10.1177/1526602815619409] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate the effect of cilostazol on major outcomes after carotid artery stenting (CAS). METHODS A systematic literature review was conducted conforming to established criteria in order to identify articles published prior to May 2015 evaluating major post-CAS outcomes in patients treated with cilostazol vs patients not treated with cilostazol. Major outcomes included in-stent restenosis (ISR) within the observation period, the revascularization rate, major/minor bleeding, and the myocardial infarction/stroke/death rate (MI/stroke/death) at 30 days and within the observation period. Data were pooled for all studies containing adequate data for each outcome investigated; effect estimates are presented as the odds ratios (ORs) and 95 confidence intervals (CI). RESULTS Overall, 7 studies pertaining to 1297 patients were eligible. Heterogeneity was low among studies so a fixed-effect analysis was conducted. Six studies (n=1233) were compared for the ISR endpoint, showing a significantly lower ISR rate with cilostazol treatment after a mean follow-up of 20 months (OR 0.158, 95% CI 0.072 to 0.349, p<0.001). Five studies (n=649) were compared regarding 30-day MI/stroke/death (OR 0.724, 95% CI 0.293 to 1.789, p=0.484) and 3 studies (n=1076) were analyzed regarding MI/stroke/death within the entire follow-up period (OR 0.768, 95% CI 0.477 to 1.236, p=0.276); no significant difference was found between the groups. Data on bleeding rates and revascularization rates post ISR were inadequate to conduct further analysis. CONCLUSION Cilostazol seems to decrease total ISR rates in patients undergoing CAS without affecting MI/stroke/death events, both in the early and late settings.
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Affiliation(s)
- George Galyfos
- First Department of Propaedeutic Surgery, University of Athens Medical School, Hippocration Hospital, Athens, Greece Department of Vascular Surgery, KAT General Hospital, Athens, Greece
| | | | - Fragiska Sigala
- First Department of Propaedeutic Surgery, University of Athens Medical School, Hippocration Hospital, Athens, Greece
| | - Konstantina Aggeli
- First Department of Cardiology, University of Athens Medical School, Hippocration Hospital, Athens, Greece
| | - Argiri Sianou
- Department of Microbiology, University of Athens Medical School, Areteion Hospital, Athens, Greece
| | - Konstantinos Filis
- First Department of Propaedeutic Surgery, University of Athens Medical School, Hippocration Hospital, Athens, Greece
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Raslan Z, Aburima A, Naseem KM. The Spatiotemporal Regulation of cAMP Signaling in Blood Platelets-Old Friends and New Players. Front Pharmacol 2015; 6:266. [PMID: 26617518 PMCID: PMC4639615 DOI: 10.3389/fphar.2015.00266] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/26/2015] [Indexed: 11/22/2022] Open
Abstract
Atherothrombosis, the pathology underlying numerous cardiovascular diseases, is a major cause of death globally. Hyperactive blood platelets play a key role in the atherothrombotic process through the release of inflammatory mediators and formation of thrombi. In healthy blood vessels, excessive platelet activation is restricted by endothelial-derived prostacyclin (PGI2) through cyclic adenosine-5′-monophosphate (cAMP) and protein kinase A (PKA)-dependent mechanisms. Elevation in intracellular cAMP is associated with the control of a number of distinct platelet functions including actin polymerisation, granule secretion, calcium mobilization and integrin activation. Unfortunately, in atherosclerotic disease the protective effects of cAMP are compromised, which may contribute to pathological thrombosis. The cAMP signaling network in platelets is highly complex with the presence of multiple isoforms of adenylyl cyclase (AC), PKA, and phosphodiesterases (PDEs). However, a precise understanding of the relationship between specific AC, PKA, and PDE isoforms, and how individual signaling substrates are targeted to control distinct platelet functions is still lacking. In other cells types, compartmentalisation of cAMP signaling has emerged as a key mechanism to allow precise control of specific cell functions. A-kinase anchoring proteins (AKAPs) play an important role in this spatiotemporal regulation of cAMP signaling networks. Evidence of AKAP-mediated compartmentalisation of cAMP signaling in blood platelets has begun to emerge and is providing new insights into the regulation of platelet function. Dissecting the mechanisms that allow cAMP to control excessive platelet activity without preventing effective haemostasis may unleash the possibility of therapeutic targeting of the pathway to control unwanted platelet activity.
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Affiliation(s)
- Zaher Raslan
- Centre for Cardiovascular and Metabolic Research, Hull-York Medical School, University of Hull , Hull, UK
| | - Ahmed Aburima
- Centre for Cardiovascular and Metabolic Research, Hull-York Medical School, University of Hull , Hull, UK
| | - Khalid M Naseem
- Centre for Cardiovascular and Metabolic Research, Hull-York Medical School, University of Hull , Hull, UK
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Mawhin MA, Tilly P, Fabre JE. The receptor EP3 to PGE2: A rational target to prevent atherothrombosis without inducing bleeding. Prostaglandins Other Lipid Mediat 2015; 121:4-16. [PMID: 26463849 DOI: 10.1016/j.prostaglandins.2015.10.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 09/23/2015] [Accepted: 10/01/2015] [Indexed: 10/22/2022]
Abstract
The prostanoid E2 (PGE2) is known to modulate the aggregative response of platelets to their conventional agonists such as ADP, TXA2, thrombin or collagen. Through the activation of its receptor EP3, PGE2 sensitizes platelets to their agonists but also inhibits them through its two other receptors, EP2 and EP4. In mice, the net result of these opposed actions is the EP3-mediated potentiation of platelet aggregation and the in vivo aggravation of murine atherothrombosis. Since the pathway PGE2/EP3 is not involved in murine hemostasis, we propose a "platelet EP3 paradigm" to describe this apparently paradoxical association between the facilitating impact on atherothrombosis and the unaltered hemostasis. Consistent with this paradigm, a drug blocking EP3 dramatically decreased atherothrombosis without inducing bleeding in mice. In humans, several studies did not agree on the effect of PGE2 on platelets. Reinterpreting these data with the notion of "potentiation window" and taking the platelet initial cAMP level into account reconciled these inconsistent results. Thereby, the in vitro potentiating effect of PGE2 on human platelets becomes clear. In addition, the EP3 blocking drug DG-041 abrogated the potentiating effect of PGE2 in whole human blood but did not prolong bleeding times in volunteers. Thus, the murine "platelet EP3 paradigm" would apply to humans if the aggravating role of PGE2 on atherothrombosis is shown in patients. Therefore, testing an EP3 blocker in a phase III trial would be of high interest to fulfill the unmet medical need which is to control atherothrombosis without impacting hemostasis and thus to improve the prevention of myocardial infarction.
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Affiliation(s)
- Marie-Anne Mawhin
- LVTS, Institut National de la santé et de la recherche Médicale U1148, Hôpital Bichat, Paris, 18ième, France
| | - Peggy Tilly
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
| | - Jean-Etienne Fabre
- LVTS, Institut National de la santé et de la recherche Médicale U1148, Hôpital Bichat, Paris, 18ième, France.
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Huh JH, Seok H, Lee BW, Kang ES, Lee HC, Cha BS. Effect of cilostazol on carotid intima-media thickness in type 2 diabetic patients without cardiovascular event. Endocrine 2014; 47:138-45. [PMID: 24381128 DOI: 10.1007/s12020-013-0120-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 11/08/2013] [Indexed: 11/28/2022]
Abstract
We investigated the efficacy of cilostazol treatment for 2 years on the attenuation of carotid intima-media thickness (IMT) progression in type 2 diabetic patients without cardiovascular disease history, as compared with other antiplatelet agents. We recruited a total of 230 type 2 diabetic patients who had undergone IMT measurement twice within 1.5-2.5 years (mean 2.06 ± 0.32 years) interval. Among these participants, we classified them into three groups according to antiplatelet agent administration at baseline: Group I (n = 66), antiplatelet naïve; Group II (n = 75), other antiplatelet agent administration; and Group III (n = 50), cilostazol administration. We then analyzed the changes in clinical characteristics from baseline to 2 years. The changes in annual mean IMT at 2 years were 0.019 ± 0.045 mm/year, -0.001 ± 0.058 mm/year, and -0.019 ± 0.043 mm/year for Group I, II, and III, respectively (P < 0.001). Mean change in total cholesterol, low-density lipoprotein-cholesterol, and triglyceride compared with baseline decreased the most in Group III even after adjustment for statin use. We also observed that the odds ratio of carotid IMT progression at 2 years was the lowest in patients who were treated with cilostazol even after adjustment for change of metabolic parameters. When we categorized patients according to baseline carotid IMT tertile, the efficacy of cilostazol against carotid IMT progression was significant only when baseline IMT was over 0.662 mm (mean 0.801). Two-year treatment with cilostazol strongly inhibited carotid IMT progression compared to other antiplatelet agents in type 2 diabetic patients. This beneficial effect of cilostazol was significant when baseline IMT was thicker than 0.662 mm (mean 0.801 mm).
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Affiliation(s)
- Ji Hye Huh
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Korea
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Nygaard G, Herfindal L, Kopperud R, Aragay AM, Holmsen H, Døskeland SO, Kleppe R, Selheim F. Time-dependent inhibitory effects of cGMP-analogues on thrombin-induced platelet-derived microparticles formation, platelet aggregation, and P-selectin expression. Biochem Biophys Res Commun 2014; 449:357-63. [PMID: 24845383 DOI: 10.1016/j.bbrc.2014.05.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 05/13/2014] [Indexed: 10/25/2022]
Abstract
In platelets, nitric oxide (NO) activates cGMP/PKG signalling, whereas prostaglandins and adenosine signal through cAMP/PKA. Cyclic nucleotide signalling has been considered to play an inhibitory role in platelets. However, an early stimulatory effect of NO and cGMP-PKG signalling in low dose agonist-induced platelet activation have recently been suggested. Here, we investigated whether different experimental conditions could explain some of the discrepancy reported for platelet cGMP-PKG-signalling. We treated gel-filtered human platelets with cGMP and cAMP analogues, and used flow cytometric assays to detect low dose thrombin-induced formation of small platelet aggregates, single platelet disappearance (SPD), platelet-derived microparticles (PMP) and thrombin receptor agonist peptide (TRAP)-induced P-selectin expression. All four agonist-induced platelet activation phases were blocked when platelets were costimulated with the PKG activators 8-Br-PET-cGMP or 8-pCPT-cGMP and low-doses of thrombin or TRAP. However, extended incubation with 8-Br-PET-cGMP decreased its inhibition of TRAP-induced P-selectin expression in a time-dependent manner. This effect did not involve desensitisation of PKG or PKA activity, measured as site-specific VASP phosphorylation. Moreover, PKG activators in combination with the PKA activator Sp-5,6-DCL-cBIMPS revealed additive inhibitory effect on TRAP-induced P-selectin expression. Taken together, we found no evidence for a stimulatory role of cGMP/PKG in platelets activation and conclude rather that cGMP/PKG signalling has an important inhibitory function in human platelet activation.
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Affiliation(s)
- Gyrid Nygaard
- Proteomic Unit at University of Bergen (PROBE), University of Bergen, Bergen, Norway; Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Lars Herfindal
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Reidun Kopperud
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Anna M Aragay
- Department of Biomedicine, University of Bergen, Bergen, Norway; Molecular Biology Institute of Barcelona (IBMB, CSIC), Barcelona, Spain
| | - Holm Holmsen
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | | | - Rune Kleppe
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Frode Selheim
- Proteomic Unit at University of Bergen (PROBE), University of Bergen, Bergen, Norway; Department of Biomedicine, University of Bergen, Bergen, Norway.
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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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de Witt SM, Verdoold R, Cosemans JM, Heemskerk JW. Insights into platelet-based control of coagulation. Thromb Res 2014; 133 Suppl 2:S139-48. [DOI: 10.1016/s0049-3848(14)50024-2] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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De Caterina R. Inhibiting thrombosis without causing bleeding: can EP3 blockers fulfil the dream? Cardiovasc Res 2014; 101:335-8. [DOI: 10.1093/cvr/cvu020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Tilly P, Charles AL, Ludwig S, Slimani F, Gross S, Meilhac O, Geny B, Stefansson K, Gurney ME, Fabre JE. Blocking the EP3 receptor for PGE2 with DG-041 decreases thrombosis without impairing haemostatic competence. Cardiovasc Res 2013; 101:482-91. [PMID: 24323317 DOI: 10.1093/cvr/cvt276] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AIMS Haemostasis interrupts bleeding from disrupted blood vessels by activating platelet aggregation and coagulation. A similar mechanism termed thrombosis generates obstructive thrombi inside diseased arteries. As a consequence of this similarity, current anti-thrombotic agents increase the risk of bleeding. Atherosclerotic plaques produce significant amounts of prostaglandin E2 (PGE2), which activates its receptor EP3 on platelets and aggravates atherothrombosis. We investigated whether blocking EP3 could dissociate atherothrombosis from haemostasis. METHODS AND RESULTS Inhibiting in vivo the receptor EP3 for PGE2 with the blocking agent DG-041 reduced murine thrombosis triggered by local delivery of arachidonic acid or ferric chloride on healthy arteries. Importantly, it also reduced thrombosis triggered by scratching murine atherosclerotic plaques. PGE2 was not produced at the bleeding site after tail clipping. Consistently, blocking EP3 did not alter murine tail, liver, or cerebral haemostasis. Furthermore, blocking EP3 reduced murine pulmonary embolism and intensified platelet inhibition by clopidogrel leaving tail bleeding times unchanged. Human atherosclerotic plaques produced PGE2, which facilitated platelet aggregation in human blood and rescued the function of P2Y12-blocked platelets. Finally, in healthy patients, DG-041 reduced platelet aggregation, but did not significantly alter the cutaneous bleeding time at doses up to eight times the dose that inhibited the facilitating effect of PGE2 on platelets. CONCLUSION In mice, blocking EP3 inhibited atherothrombosis without affecting haemostasis and intensified efficiency of conventional anti-platelet treatment without aggravating the bleeding risk. In patients, blocking EP3 should improve the prevention of cardiovascular diseases, which is currently limited by the risk of bleeding.
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Affiliation(s)
- Peggy Tilly
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Institut National de la Santé et de la Recherche Médicale U596, Centre National de la Recherche Scientifique UMR7104, Université Louis Pasteur, 67400 Illkirch, France
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Fuentes E, Badimon L, Caballero J, Padró T, Vilahur G, Alarcón M, Pérez P, Palomo I. Protective mechanisms of adenosine 5'-monophosphate in platelet activation and thrombus formation. Thromb Haemost 2013; 111:491-507. [PMID: 24306059 DOI: 10.1160/th13-05-0386] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 10/28/2013] [Indexed: 11/05/2022]
Abstract
Platelet activation is relevant to a variety of acute thrombotic events. We sought to examine adenosine 5'-monophosphate (AMP) mechanisms of action in preventing platelet activation, thrombus formation and platelet-related inflammatory response. We assessed the effect of AMP on 1) P-selectin expression and GPIIb/IIIa activation by flow cytometry; 2) Platelet aggregation and ATP secretion induced by ADP, collagen, TRAP-6, convulxin and thrombin; 3) Platelet rolling and firm adhesion, and platelet-leukocyte interactions under flow-controlled conditions; and, 4) Platelet cAMP levels, sP-selectin, sCD40L, IL-1β, TGF-β1 and CCL5 release, PDE3A activity and PKA phosphorylation. The effect of AMP on in vivo thrombus formation was also evaluated in a murine model. The AMP docking with respect to A2 adenosine receptor was determined by homology. AMP concentration-dependently (0.1 to 3 mmol/l) inhibited P-selectin expression and GPIIb/IIIa activation, platelet secretion and aggregation induced by ADP, collagen, TRAP-6 and convulxin, and diminished platelet rolling and firm adhesion. Furthermore, AMP induced a marked increase in the rolling speed of leukocytes retained on the platelet surface. At these concentrations AMP significantly decreased inflammatory mediator from platelet, increased intraplatelet cAMP levels and inhibited PDE3A activity. Interestingly, SQ22536, ZM241385 and SCH58261 attenuated the antiplatelet effect of AMP. Docking experiments revealed that AMP had the same orientation that adenosine inside the A2 adenosine receptor binding pocket. These in vitro antithrombotic properties were further supported in an in vivo model of thrombosis. Considering the successful use of combined antiplatelet therapy, AMP may be further developed as a novel antiplatelet agent.
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Affiliation(s)
| | | | | | | | | | | | | | - I Palomo
- Iván Palomo G., PhD, Immunology and Haematology Laboratory, Faculty of Health Sciences, Universidad de Talca, Casilla: 747, Talca, Chile, Tel.: +56 71 200493, Fax: +56 71 20048, E-mail:
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Relationship between Platelet PPARs, cAMP Levels, and P-Selectin Expression: Antiplatelet Activity of Natural Products. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:861786. [PMID: 24324520 PMCID: PMC3845334 DOI: 10.1155/2013/861786] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 09/23/2013] [Indexed: 11/22/2022]
Abstract
Platelets are no longer considered simply as cells participating in thrombosis. In atherosclerosis, platelets are regulators of multiple processes, with the recruitment of inflammatory cells towards the lesion sites, inflammatory mediators release, and regulation of endothelial function. The antiplatelet therapy has been used for a long time in an effort to prevent and treat cardiovascular diseases. However, limited efficacy in some patients, drug resistance, and side effects are limitations of current antiplatelet therapy. In this context, a large number of natural products (polyphenols, terpenoids, alkaloids, and fatty acids) have been reported with antiplatelet activity. In this sense, the present paper describes mechanisms of antiplatelet action of natural products on platelet P-selectin expression through cAMP levels and its role as peroxisome proliferator-activated receptors agonists.
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Protective Mechanisms of S. lycopersicum Aqueous Fraction (Nucleosides and Flavonoids) on Platelet Activation and Thrombus Formation: In Vitro, Ex Vivo and In Vivo Studies. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:609714. [PMID: 24159349 PMCID: PMC3789491 DOI: 10.1155/2013/609714] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 07/14/2013] [Accepted: 08/08/2013] [Indexed: 12/20/2022]
Abstract
The purpose of this research was to investigate mechanisms of antiplatelet action of bioactive principle from S. lycopersicum. Aqueous fraction had a high content of nucleosides (adenosine, guanosine, and adenosine 5′-monophosphate) by HPLC analysis. Also aqueous fraction presented flavonoids content. Aqueous fraction inhibited platelet activation by 15 ± 6% (P < 0.05). Fully spread of human platelets on collagen in the presence of aqueous fraction was inhibited from 15 ± 1 to 9 ± 1 μm2 (P < 0.001). After incubation of whole blood with aqueous fraction, the platelet coverage was inhibited by 55 ± 12% (P < 0.001). Platelet ATP secretion and aggregation were significantly inhibited by the aqueous fraction. At the same concentrations that aqueous fraction inhibits platelet aggregation, levels of sCD40L significantly decreased and the intraplatelet cAMP levels increased. In addition, SQ22536, an adenylate cyclase inhibitor, attenuated the effect of aqueous fraction toward ADP-induced platelet aggregation and intraplatelet level of cAMP. Platelet aggregation ex vivo (human study) and thrombosis formation in vivo (murine model) were inhibited by aqueous fraction. Finally, aqueous fraction may be used as a functional ingredient adding antiplatelet activities (nucleosides and flavonoids) to processed foods.
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Kobsar A, Putz E, Yilmaz P, Weinig E, Boeck M, Koessler J. Decreasing phosphodiesterase 5A activity contributes to platelet cGMP accumulation during storage of apheresis-derived platelet concentrates. Transfusion 2013; 54:1008-14. [PMID: 23909451 DOI: 10.1111/trf.12360] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 06/12/2013] [Accepted: 06/12/2013] [Indexed: 12/26/2022]
Abstract
BACKGROUND Platelet storage lesion (PSL) considerably decreases the quality of platelets (PLTs) in concentrates characterized by a loss of signaling responses to agonists and impaired PLT activation, secretion, and aggregation. To understand the role of inhibitory signaling pathways in the mechanism of PSL, the basal state of the cyclic nucleotide (CN)-dependent signaling systems in stored PLTs was investigated. STUDY DESIGN AND METHODS Whole blood samples (WB) and apheresis-derived PLT concentrates (APCs) were obtained from healthy volunteers. Washed PLTs were prepared from WB on Day 0 and from APCs on Days 0, 2, and 5. The basal phosphorylation of the vasodilator-stimulated phosphoprotein (VASP) and phosphodiesterase 5A (PDE5A) levels were quantified by Western blot. CN and PDE5A activity were measured by enzyme-linked immunoassay kits. Fibrinogen binding and aggregation were measured in PLT-rich plasma of WB or APC samples. Unpaired t test was used for statistical analysis. RESULTS Basal VASP phosphorylation levels were comparable in WB and APCs on Day 0. VASP phosphorylation increased significantly during storage of APCs, more pronounced at Ser(239) than at Ser(157) . Similarly, intracellular cGMP, but not cAMP, concentration continuously increased in stored PLTs, whereas PDE5A levels and activity significantly decreased accompanied by diminished thrombin receptor activator peptide 6-induced fibrinogen binding and aggregation. CONCLUSION Storage of APCs leads to intracellular cGMP accumulation that could be caused by degradation of PDE5A. Enhanced cGMP level supports subsequent cGMP-dependent protein kinase-mediated increase of VASP phosphorylation resulting in reduced fibrinogen binding and aggregation.
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Affiliation(s)
- Anna Kobsar
- Institute of Transfusion Medicine and Haemotherapy, University of Wuerzburg, Wuerzburg, Germany
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30
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Boyle KL, Leech E. A review of the pharmacology and clinical uses of pimobendan. J Vet Emerg Crit Care (San Antonio) 2013; 22:398-408. [PMID: 22928748 DOI: 10.1111/j.1476-4431.2012.00768.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To review the pharmacology, research developments, and clinical uses of pimobendan DATA SOURCES Original research articles and clinical studies from 1984 to August 2011. VETERINARY DATA SYNTHESIS Pimobendan is approved for use in dogs for the treatment of congestive heart failure (CHF) secondary to chronic valvular heart disease (CVHD) and dilated cardiomyopathy (DCM). Expert-based veterinary guidelines recommend the use of pimobendan in the management of acute, hospital-based therapy for patients with CHF attributable to CVHD. CONCLUSIONS The use of pimobendan, an inodilator with phosphodiesterase 3 (PDE3) inhibitory and calcium-sensitizing properties, is regarded as a component of the standard of care in the management of dogs with CHF secondary to both DCM and CVHD. Further studies are warranted to confirm the safety and efficacy of pimobendan for the off-label use of this drug in asymptomatic CVHD, pulmonary arterial hypertension, asymptomatic myocardial diseases, CHF from all other causes and in cats with CHF.
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Affiliation(s)
- Kimberly L Boyle
- VCA All-Care Animal Referral Center, Fountain Valley, CA, 92708, USA.
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31
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Mischnik M, Boyanova D, Hubertus K, Geiger J, Philippi N, Dittrich M, Wangorsch G, Timmer J, Dandekar T. A Boolean view separates platelet activatory and inhibitory signalling as verified by phosphorylation monitoring including threshold behaviour and integrin modulation. MOLECULAR BIOSYSTEMS 2013; 9:1326-39. [DOI: 10.1039/c3mb25597b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Mendes-Silverio CB, Leiria LOS, Morganti RP, Anhê GF, Marcondes S, Mónica FZ, De Nucci G, Antunes E. Activation of haem-oxidized soluble guanylyl cyclase with BAY 60-2770 in human platelets lead to overstimulation of the cyclic GMP signaling pathway. PLoS One 2012; 7:e47223. [PMID: 23144808 PMCID: PMC3493568 DOI: 10.1371/journal.pone.0047223] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 09/12/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND AND AIMS Nitric oxide-independent soluble guanylyl cyclase (sGC) activators reactivate the haem-oxidized enzyme in vascular diseases. This study was undertaken to investigate the anti-platelet mechanisms of the haem-independent sGC activator BAY 60-2770 in human washed platelets. The hypothesis that sGC oxidation potentiates the anti-platelet activities of BAY 60-2770 has been tested. METHODS Human washed platelet aggregation and adhesion assays, as well as flow cytometry for α(IIb)β(3) integrin activation and Western blot for α1 and β1 sGC subunits were performed. Intracellular calcium levels were monitored in platelets loaded with a fluorogenic calcium-binding dye (FluoForte). RESULTS BAY 60-2770 (0.001-10 µM) produced significant inhibition of collagen (2 µg/ml)- and thrombin (0.1 U/ml)-induced platelet aggregation that was markedly potentiated by the sGC inhibitor ODQ (10 µM). In fibrinogen-coated plates, BAY 60-2770 significantly inhibited platelet adhesion, an effect potentiated by ODQ. BAY 60-2770 increased the cGMP levels and reduced the intracellular Ca(2+) levels, both of which were potentiated by ODQ. The cell-permeable cGMP analogue 8-Br-cGMP (100 µM) inhibited platelet aggregation and Ca(2+) levels in an ODQ-insensitive manner. The cAMP levels remained unchanged by BAY 60-2770. Collagen- and thrombin-induced α(IIb)β(3) activation was markedly inhibited by BAY 60-2770 that was further inhibited by ODQ. The effects of sodium nitroprusside (3 µM) were all prevented by ODQ. Incubation with ODQ (10 µM) significantly reduced the protein levels of α1 and β1 sGC subunits, which were prevented by BAY 60-2770. CONCLUSION The inhibitory effects of BAY 60-2770 on aggregation, adhesion, intracellular Ca(2+) levels and α(IIb)β(3) activation are all potentiated in haem-oxidizing conditions. BAY 60-2770 prevents ODQ-induced decrease in sGC protein levels. BAY 60-2770 could be of therapeutic interest in cardiovascular diseases associated with thrombotic complications.
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Affiliation(s)
- Camila B. Mendes-Silverio
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Luiz O. S. Leiria
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Rafael P. Morganti
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Gabriel F. Anhê
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Sisi Marcondes
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Fabíola Z. Mónica
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Gilberto De Nucci
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
- * E-mail:
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Effects of cilostazol against the progression of carotid IMT in symptomatic ischemic stroke patients. J Neurol 2012; 260:122-30. [PMID: 22820682 PMCID: PMC3535378 DOI: 10.1007/s00415-012-6599-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 06/19/2012] [Accepted: 06/21/2012] [Indexed: 01/17/2023]
Abstract
Carotid intima-media thickness (IMT) is a surrogate marker for evaluating atherosclerotic vascular diseases. The phosphodiesterase inhibitor cilostazol attenuates the increase in carotid IMT in diabetes patients. We studied whether cilostazol can reduce the progression of carotid IMT in symptomatic ischemic stroke patients. From our prospective registry of acute ischemic stroke patients who were admitted during a 4.5-year period, follow-up carotid ultrasound was performed in a random sample of survivors. Patients were divided into two groups: the cilostazol group, who continued cilostazol treatment during the follow-up period; and the control group, who were prescribed antiplatelets other than cilostazol. Analysis of covariance and propensity score-matched analysis were used to evaluate the difference between groups. Among a total of 1,049 cases in our registry, 208 patients were utilized to construct two comparable sets by propensity score analysis, including 101 who received cilostazol and 107 who took antiplatelet medication without cilostazol. Both maximum and mean carotid IMT values were significantly reduced in the cilostazol group but increased in the control group (maximum left –0.048 ± 0.186 vs. 0.022 ± 0.163 mm, p = 0.001; maximum right –0.037 ± 0.173 vs. 0.050 ± 0.200 mm, p = 0.001; mean left –0.052 ± 0.102 vs. 0.023 ± 0.112 mm, p < 0.001; and mean right –0.038 ± 0.106 vs. 0.042 ± 0.139 mm, p < 0.001). After matching by propensity score, the improvements in both maximum and mean carotid IMT values in the cilostazol group remained significant. This study shows that cilostazol causes a significant regression in carotid IMT in symptomatic stroke patients.
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Abstract
Endothelial prostacyclin and nitric oxide potently inhibit platelet functions. Prostacyclin and nitric oxide actions are mediated by platelet adenylyl and guanylyl cyclases, which synthesize cyclic AMP (cAMP) and cyclic GMP (cGMP), respectively. Cyclic nucleotides stimulate cAMP-dependent protein kinase (protein kinase A [PKA]I and PKAII) and cGMP-dependent protein kinase (protein kinase G [PKG]I) to phosphorylate a broad panel of substrate proteins. Substrate phosphorylation results in the inactivation of small G-proteins of the Ras and Rho families, inhibition of the release of Ca(2+) from intracellular stores, and modulation of actin cytoskeleton dynamics. Thus, PKA/PKG substrates translate prostacyclin and nitric oxide signals into a block of platelet adhesion, granule release, and aggregation. cAMP and cGMP are degraded by phosphodiesterases, which might restrict signaling to specific subcellular compartments. An emerging principle of cyclic nucleotide signaling in platelets is the high degree of interconnection between activating and cAMP/cGMP-dependent inhibitory signaling pathways at all levels, including cAMP/cGMP synthesis and breakdown, and PKA/PKG-mediated substrate phosphorylation. Furthermore, defects in cAMP/cGMP pathways might contribute to platelet hyperreactivity in cardiovascular disease. This article focuses on recent insights into the regulation of the cAMP/cGMP signaling network and on new targets of PKA and PKG in platelets.
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Affiliation(s)
- A Smolenski
- UCD Conway Institute, UCD School of Medicine and Medical Science, University College Dublin, Belfield, Dublin, Ireland.
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Srivastava K, Bath PMW, Bayraktutan U. Current therapeutic strategies to mitigate the eNOS dysfunction in ischaemic stroke. Cell Mol Neurobiol 2011; 32:319-36. [PMID: 22198555 DOI: 10.1007/s10571-011-9777-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 11/29/2011] [Indexed: 12/22/2022]
Abstract
Impairment of endothelial nitric oxide synthase (eNOS) activity is implicated in the pathogenesis of endothelial dysfunction in many diseases including ischaemic stroke. The modulation of eNOS during and/or following ischaemic injury often represents a futile compensatory mechanism due to a significant decrease in nitric oxide (NO) bioavailability coupled with dramatic increases in the levels of reactive oxygen species that further neutralise NO. However, applications of a number of therapeutic agents alone or in combination have been shown to augment eNOS activity under a variety of pathological conditions by potentiating the expression and/or activity of Akt/eNOS/NO pathway components. The list of these therapeutic agents include NO donors, statins, angiotensin-converting enzyme inhibitors, calcium channel blockers, phosphodiesterase-3 inhibitors, aspirin, dipyridamole and ellagic acid. While most of these compounds exhibit anti-platelet properties and are able to up-regulate eNOS expression in endothelial cells and platelets, others suppress eNOS uncoupling and tetrahydrobiopterin (an eNOS stabiliser) oxidation. As the number of therapeutic molecules that modulate the expression and activity of eNOS increases, further detailed research is required to reveal their mode of action in preventing and/or reversing the endothelial dysfunction.
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Affiliation(s)
- Kirtiman Srivastava
- Division of Stroke, Clinical Sciences Building, Nottingham City Hospital Campus, The University of Nottingham, Nottingham, UK.
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Wangorsch G, Butt E, Mark R, Hubertus K, Geiger J, Dandekar T, Dittrich M. Time-resolved in silico modeling of fine-tuned cAMP signaling in platelets: feedback loops, titrated phosphorylations and pharmacological modulation. BMC SYSTEMS BIOLOGY 2011; 5:178. [PMID: 22034949 PMCID: PMC3247139 DOI: 10.1186/1752-0509-5-178] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 10/28/2011] [Indexed: 02/13/2023]
Abstract
Background Hemostasis is a critical and active function of the blood mediated by platelets. Therefore, the prevention of pathological platelet aggregation is of great importance as well as of pharmaceutical and medical interest. Endogenous platelet inhibition is predominantly based on cyclic nucleotides (cAMP, cGMP) elevation and subsequent cyclic nucleotide-dependent protein kinase (PKA, PKG) activation. In turn, platelet phosphodiesterases (PDEs) and protein phosphatases counterbalance their activity. This main inhibitory pathway in human platelets is crucial for countervailing unwanted platelet activation. Consequently, the regulators of cyclic nucleotide signaling are of particular interest to pharmacology and therapeutics of atherothrombosis. Modeling of pharmacodynamics allows understanding this intricate signaling and supports the precise description of these pivotal targets for pharmacological modulation. Results We modeled dynamically concentration-dependent responses of pathway effectors (inhibitors, activators, drug combinations) to cyclic nucleotide signaling as well as to downstream signaling events and verified resulting model predictions by experimental data. Experiments with various cAMP affecting compounds including anti-platelet drugs and their combinations revealed a high fidelity, fine-tuned cAMP signaling in platelets without cross-talk to the cGMP pathway. The model and the data provide evidence for two independent feedback loops: PKA, which is activated by elevated cAMP levels in the platelet, subsequently inhibits adenylyl cyclase (AC) but as well activates PDE3. By multi-experiment fitting, we established a comprehensive dynamic model with one predictive, optimized and validated set of parameters. Different pharmacological conditions (inhibition, activation, drug combinations, permanent and transient perturbations) are successfully tested and simulated, including statistical validation and sensitivity analysis. Downstream cyclic nucleotide signaling events target different phosphorylation sites for cAMP- and cGMP-dependent protein kinases (PKA, PKG) in the vasodilator-stimulated phosphoprotein (VASP). VASP phosphorylation as well as cAMP levels resulting from different drug strengths and combined stimulants were quantitatively modeled. These predictions were again experimentally validated. High sensitivity of the signaling pathway at low concentrations is involved in a fine-tuned balance as well as stable activation of this inhibitory cyclic nucleotide pathway. Conclusions On the basis of experimental data, literature mining and database screening we established a dynamic in silico model of cyclic nucleotide signaling and probed its signaling sensitivity. Thoroughly validated, it successfully predicts drug combination effects on platelet function, including synergism, antagonism and regulatory loops.
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Affiliation(s)
- Gaby Wangorsch
- Department of Bioinformatics, Biocenter, University of Würzburg, Germany
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Roger S, Badier-Commander C, Paysant J, Cordi A, Verbeuren TJ, Félétou M. The anti-aggregating effect of BAY 41-2272, a stimulator of soluble guanylyl cyclase, requires the presence of nitric oxide. Br J Pharmacol 2011; 161:1044-58. [PMID: 20977455 DOI: 10.1111/j.1476-5381.2010.00943.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE The purpose of the present study was to determine whether a stimulator of soluble guanylyl cyclase, BAY 41-2272, inhibits platelet aggregation and to clarify its interaction with nitric oxide (NO). EXPERIMENTAL APPROACH Blood was collected from anaesthetized Wistar Kyoto rats. The aggregation of washed platelets was measured and the production of cAMP and cGMP was determined. KEY RESULTS In adenosine 5'-diphosphate (ADP)-induced platelet aggregation, the anti-aggregating effects of BAY 41-2272, nitroglycerin, sodium nitroprusside and DEA-NONOate were associated with increased levels of cGMP while that of beraprost, a prostacyclin analogue, was correlated with an increase in cAMP. 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) prevented the effects of BAY 41-2272 and that of nitroglycerin and sodium nitroprusside, but only inhibited the increase in cGMP produced by of DEA-NONOate. Hydroxocobalamin, an NO scavenger, inhibited the effects of the three NO donors and BAY 41-2272 but did not affect those of beraprost. ADP-induced aggregation and the effects of BAY 41-2272 were not affected by L-nitroarginine. A positive interaction was observed between BAY 41-2272 and the three NO donors. BAY 41-2272 potentiated also the anti-aggregating effects of beraprost, and again this potentiation was inhibited by hydroxocobalamin. CONCLUSIONS AND IMPLICATIONS Inhibition of platelet aggregation by BAY 41-2272 requires the reduced form of soluble guanylyl cyclase and the presence of NO. The positive interaction observed between BAY 41-2272 and various NO donors is qualitatively similar whatever the mechanism involved in NO release. Furthermore, a potent synergism is observed between BAY 41-2272 and a prostacyclin analogue, but only in the presence of NO.
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Affiliation(s)
- Séverine Roger
- Département Angiologie, Institut de Recherches Servier, 11 rue des Moulineaux, Suresnes, France
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Anti-aggregating effect of BAY 58-2667, an activator of soluble guanylyl cyclase. Vascul Pharmacol 2010; 53:281-7. [PMID: 20933607 DOI: 10.1016/j.vph.2010.09.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 09/21/2010] [Accepted: 09/30/2010] [Indexed: 11/23/2022]
Abstract
The purpose of the present study was to determine whether an activator of soluble guanylyl cyclase (sGC), BAY 58-2667, inhibits platelet aggregation and to clarify its mechanism of action. Blood was collected from anesthetized WKY rats. The aggregation of washed platelet was measured and the production of cAMP and cGMP was determined. BAY 58-2667 produced a partial inhibition of the ADP- and collagen-induced platelet aggregation, but did not significantly affect thrombin-induced aggregation. In ADP-induced platelet aggregation, the inhibitory effects of BAY 58-2667 were associated with an increased level of both cGMP and cAMP while that of the prostacyclin analogue, beraprost, was correlated only with an increase in cAMP. The inhibitor of sGC, ODQ, enhanced the effects of BAY 58-2667. The presence of L-nitroarginine, an inhibitor of NO-synthase, hydroxocobalamin, a scavenger of NO, or that of three different NO-donors did not affect the anti-aggregating effect of BAY 58-2667. However, the anti-aggregating effects of beraprost were potentiated by BAY 58-2667. Therefore, the platelet inhibitory effects of BAY 58-2667 are associated with the generation of cGMP and a secondary increase in cAMP, both being totally NO-independent. When the sGC is oxidized, BAY 58-2667 becomes a relevant anti-aggregating agent, which synergizes with the cAMP-dependent pathway.
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Thrombospondin-1 induces platelet activation through CD36-dependent inhibition of the cAMP/protein kinase A signaling cascade. Blood 2010; 116:4297-306. [PMID: 20664056 DOI: 10.1182/blood-2010-01-265561] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Cyclic adenosine monophosphate (cAMP)-dependent signaling modulates platelet function at sites of vascular injury. Here we show that thrombospondin-1 (TSP-1) prevents cAMP/protein kinase A (PKA) signaling through a CD36-dependent mechanism. Prostaglandin E₁ (PGE₁) induced a robust inhibition of both platelet aggregation and platelet arrest under physiologic conditions of flow. Exogenous TSP-1 reduced significantly PGE₁-mediated inhibition of both platelet aggregation and platelet arrest. TSP-1 prevented PGE₁-stimulated cAMP accrual and phosphorylation of PKA substrates, through a mechanism requiring phosphodiesterase3A. TSP-1 also inhibited VASP phosphorylation stimulated by the nonhydrolyzable cAMP analog, 8-bromo-cAMP, indicating that it may regulate cAMP-mediated activation of PKA. The inhibitory effect of TSP-1 on cAMP signaling could be reproduced with a peptide possessing a CD36 binding sequence of TSP-1, while the effects of TSP-1 were prevented by a CD36 blocking antibody. TSP-1 and the CD36 binding peptide induced phosphorylation of Src kinases, p38 and JNK. Moreover, inhibition of Src kinases blocked TSP-1-mediated regulation of cAMP concentrations and the phosphorylation of VASP, indicating that TSP-1 modulated the cAMP/PKA signaling events through a tyrosine kinase-dependent pathway downstream of CD36. These data reveal a new role for TSP-1 in promoting platelet aggregation through modulation of the cAMP-PKA signaling pathway.
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Brito FCF, Kummerle AE, Lugnier C, Fraga CAM, Barreiro EJ, Miranda ALP. Novel thienylacylhydrazone derivatives inhibit platelet aggregation through cyclic nucleotides modulation and thromboxane A2 synthesis inhibition. Eur J Pharmacol 2010; 638:5-12. [PMID: 20412790 DOI: 10.1016/j.ejphar.2010.04.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 03/11/2010] [Accepted: 04/01/2010] [Indexed: 10/19/2022]
Abstract
The aim of this study has been to investigate the antiplatelet activity of a new series of thienylacylhydrazone derivatives analogous to the lead compound LASSBio-294 ((2-thienylidene) 3,4-methylenedioxybenzoylhydrazine). The antiplatelet effect was investigated in rabbit and human platelet rich plasma stimulated by arachidonic acid, collagen, ADP and in washed platelet stimulated by thrombin. The effects on the production of cyclic nucleotides and thromboxane A(2) (TXA(2)) in human platelets were also investigated. Compounds LASSBio-785 (N-Methyl (2-thienylidene) 3,4-methylenedioxybenzoylhydrazine), LASSBio-786 (N-Benzyl (2-thienylidene) 3,4-methylenedioxybenzoylhydrazine), LASSBio-787 ((5-Methyl-2-thienylidene) 3,4-methylenedioxybenzoylhydrazine), LASSBio-788 (N-Allyl (2-thienylidene) 3,4-methylenedioxybenzoylhydrazine) and LASSBio-789 ((5-Bromo-2-thienylidene) 3,4-methylenedioxybezoylhydrazine) inhibited platelet aggregation induced by arachidonic acid, collagen and ADP. LASSBio-785, LASSBio-788 and LASSBio-789 presented the higher potency in platelet aggregation induced by arachidonic acid (IC(50) values of 0.3, 0.2 and 3.1 microM, respectively) and collagen (IC(50) values of 0.9, 1.5 and 3.4 microM, respectively), with a 20 to 70-fold increase in potency compared to LASSBio-294. They inhibited the ATP release reaction by 95%, the whole blood aggregation by 35-45% and the TXB(2) production was totally abolished. In addition, they presented a significant effect on bleeding time. Qualitative studies in thrombin-induced washed platelet aggregation in the presence of sodium nitroprusside (SNP) suggested a phosphodiesterase-2 (PDE2) like effect for LASSBio-785, LASSBio-788 and LASSBio-789. They were able to increase the cGMP levels in non-stimulated platelets, in SNP-stimulated platelets and in the presence of 1-H- [1, 2, 4] oxadiazolo [4, 3- a] quinoxalin- 1- one (ODQ). The antiplatelet aggregation activity exerted by thienylacylhydrazone derivatives seems to be related to cyclic nucleotides regulation and TXA(2) synthesis inhibition. The structural modification of compound LASSBio-294 led to the optimization of its pharmacological properties and to the discovery of new potent antiplatelet prototypes with an antithrombotic potential.
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Affiliation(s)
- Fernanda C F Brito
- Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio), Departamento de Fármacos, Universidade Federal do Rio de Janeiro (UFRJ), Centro de Ciências da Saúde (CCS), P.O. Box 68006, Ilha do Fundão, 21941-902, Rio de Janeiro, RJ, Brazil
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Savai R, Pullamsetti SS, Banat GA, Weissmann N, Ghofrani HA, Grimminger F, Schermuly RT. Targeting cancer with phosphodiesterase inhibitors. Expert Opin Investig Drugs 2010; 19:117-31. [PMID: 20001559 DOI: 10.1517/13543780903485642] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
IMPORTANCE OF THE FIELD For many cancers, there has been a shift from management with traditional, nonspecific cytotoxic chemotherapies to treatment with molecule-specific targeted therapies that are used either alone or in combination with traditional chemotherapy and radiation therapy. Accumulating data suggest that multi-targeted agents may produce greater benefits than those observed with single-targeted therapies, may have acceptable tolerability profiles, and may be active against a broader range of tumour types. Thus, regulation of cyclic nucleotide signalling is properly regarded as a composite of multiple component pathways involved in diverse aspects of tumour cell function. The impairment of cAMP and/or cGMP generation by overexpression of PDE isoforms that has been described in various cancer pathologies, and the effects of PDE inhibitors in tumour models in vitro and in vivo, may offer promising insight into future cancer treatments because of the numerous advantages of PDE inhibitors. AREAS COVERED IN THIS REVIEW In this review, we focus on the expression and regulation of cyclic nucleotide phosphodiesterases (PDEs) in tumour progression and provide evidence that PDE inhibitors may be effective agents for treating cancer; the review covers literature from the past several years. WHAT THE READER WILL GAIN PDEs have been studied in a variety of tumours; data have suggested that the levels of PDE activity are elevated and, therefore, the ratio of cGMP to cAMP is affected. In addition, PDE inhibitors may be potential targets for tumour cell growth inhibition and induction of apoptosis. This review explores the prospects of targeting PDEs with therapeutic agents for cancer, as well as the shortcomings of this approach such as dose-limiting side effects, toxicity/efficacy ratio and selectivity towards tumour tissue. In addition, it includes opinions and suggestion for developing PDE inhibition for cancer treatment from initial concept to potential therapeutic application and final relevance in clinical use. TAKE HOME MESSAGE Impaired cAMP and/or cGMP generation upon overexpression of PDE isoforms has been described in various cancer pathologies. Inhibition of selective PDE isoforms, which raises the levels of intracellular cAMP and/or cGMP, induces apoptosis and cell cycle arrest in a broad spectrum of tumour cells and regulates the tumour microenvironment. Therefore, the development and clinical application of inhibitors specific for individual PDE isoenzymes may selectively restore normal intracellular signalling, providing antitumour therapy with reduced adverse effects.
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Affiliation(s)
- Rajkumar Savai
- Max-Planck-Institute for Heart and Lung Research, Department of Lung Development and Remodelling, Bad Nauheim, Germany
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42
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Proença-Ferreira R, Franco-Penteado CF, Traina F, Saad STO, Costa FF, Conran N. Increased adhesive properties of platelets in sickle cell disease: roles for alphaIIb beta3-mediated ligand binding, diminished cAMP signalling and increased phosphodiesterase 3A activity. Br J Haematol 2010; 149:280-8. [PMID: 20136824 DOI: 10.1111/j.1365-2141.2010.08087.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Whilst high pro-coagulant activity is reported in sickle cell disease (SCD), the precise role of platelets (PLTs) in SCD inflammatory and vaso-occlusive processes is unclear. Adhesion of PLTs from healthy controls (CON), SCD individuals (SCD) and SCD patients on hydroxycarbamide (SCDHC) to fibrinogen (FB) was compared using static adhesion assays. PLT adhesion molecules and intraplatelet cyclic adenosine monophosphate (icAMP) were observed by flow cytometry and enzyme-linked immunosorbent assay. SCD-PLTs demonstrated significantly greater adhesion than CON-PLTs to FB. Participation of the alpha(IIb)beta(3)-integrin in SCD-PLT adhesion was implicated by increased alpha(IIb)beta(3) activation and data showing that an alpha(IIb)beta(3)-function-inhibiting antibody significantly diminished SCD-PLT adhesion to FB. Platelet activation was potentiated by reductions in icAMP; cAMP levels were decreased in SCD-PLTs, being comparable to those of thrombin-stimulated CON-PLTs. Furthermore, SCD-PLT adhesion to FB was significantly reduced by cilostazol, an inhibitor of cAMP-hydrolyzing phosphodiesterase 3A (PDE3A). Both alpha(IIb)beta(3)-integrin activation and icAMP correlated significantly with fetal haemoglobin in SCD. Accordingly, hydroxycarbamide therapy was associated with lower PLT adhesion and higher icAMP. SCD-PLTs may be capable of adhering to proteins encountered on the inflamed vascular wall and, potentially, participate in vaso-occlusive processes. Hydroxycarbamide and, speculatively, nitric oxide donor or cyclic-nucleotide-targeted therapies may aid in the reversal of PLT adhesive properties in SCD.
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Tucker KL, Kaiser WJ, Bergeron AL, Hu H, Dong JF, Tan TH, Gibbins JM. Proteomic analysis of resting and thrombin-stimulated platelets reveals the translocation and functional relevance of HIP-55 in platelets. Proteomics 2009; 9:4340-54. [PMID: 19725075 DOI: 10.1002/pmic.200900024] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The platelet surface is a dynamic interface that changes rapidly in response to stimuli to co-ordinate the formation of thrombi at sites of vascular injury. Tight control is essential as loss of organisation may result in the inappropriate formation of thrombi (thrombosis) or excessive bleeding. In this paper we describe the comparative analysis of resting and thrombin-stimulated platelet membrane proteomes and associated proteins to identify proteins important to platelet function. Surface proteins were labelled using a biotin tag and isolated by NeurtrAvidin affinity chromatography. Liquid phase IEF and SDS-PAGE were used to separate proteins, and bands of increased intensity in the stimulated platelet fractions were digested and identified by FT-ICR mass spectrometry. Novel proteins were identified along with proteins known to be translocated to the platelet surface. Furthermore, many platelet proteins revealed changes in location associated with function, including G6B and Hip-55. HIP-55 is an SH3-binding protein important in T-cell receptor signalling. Further analysis of HIP-55 revealed that this adaptor protein becomes increasingly associated with both Syk and integrin beta3 upon platelet activation. Analysis of HIP-55 deficient platelets revealed reduced fibrinogen binding upon thrombin stimulation, suggesting HIP-55 to be an important regulator of platelet function.
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Affiliation(s)
- Katherine L Tucker
- Institute for Cardiovascular and Metabolic Research, School of Biological Sciences, The University of Reading, Whiteknights, Reading, UK.
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44
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Turner ST, Fornage M, Jack CR, Mosley TH, Knopman DS, Kardia SLR, Boerwinkle E, de Andrade M. Genomic susceptibility Loci for brain atrophy, ventricular volume, and leukoaraiosis in hypertensive sibships. ACTA ACUST UNITED AC 2009; 66:847-57. [PMID: 19597086 DOI: 10.1001/archneurol.2009.110] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
OBJECTIVE To localize susceptibility genes for alterations in brain structure associated with risk of stroke and dementia. We conducted genomewide linkage analyses for magnetic resonance imaging (MRI) measures of brain atrophy, ventricular, and subcortical white matter hyperintensity (leukoaraiosis) in 689 non-Hispanic white (673 sibling pairs; median age, 61 years) and 544 non-Hispanic black participants (503 sibling pairs; median age, 64 years) from sibships with at least 2 members with essential hypertension. DESIGN, SETTING, AND PATIENTS We determined brain, ventricular, and leukoaraiosis volumes from axial fluid-attenuated inversion recovery MRI; we calculated brain atrophy as the difference between total intracranial and brain volumes. Microsatellite markers (n = 451) distributed across the 22 autosomes were genotyped, and we used variance components methods to estimate heritability and assess evidence of genetic linkage for each MRI measure. MAIN OUTCOME MEASURES Brain atrophy ventricular volume, and leukoaraiosis determined from fluid-attenuated inversion recovery MRI. RESULTS In both races, the heritability of each MRI measure was statistically greater than 0 (P < .001), ranging in magnitude from 0.42 (for ventricular volume in blacks) to 0.69 (for brain atrophy in blacks). Based on multipoint logarithm of odds scores (MLS), the strongest evidence of genetic linkage was observed for brain atrophy on chromosomes 1 (MLS, 3.49 at 161 cM; P < .001) and 17 (MLS, 3.08 at 18 cM; P < .001) in whites; for ventricular volume on chromosome 12 (MLS, 3.67 at 49 cM; P < .001) in blacks and chromosome 10 (MLS, 2.47 at 110 cM; P < .001) in whites; and for leukoaraiosis on chromosome 11 (MLS, 2.21 at 118 cM; P < .001) in whites and chromosome 22 (MLS, 2.02 at 36 cM; P = .001) in blacks. CONCLUSIONS The MRI measures of structural brain injury are heritable in non-Hispanic black and white sibships ascertained through hypertensive sibling pairs. The susceptibility loci for brain atrophy, ventricular volume, and leukoaraiosis identified by linkage analyses differ among MRI measures and between races.
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Affiliation(s)
- Stephen T Turner
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
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45
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Role of cAMP-dependent protein kinase in the regulation of platelet procoagulant activity. Arch Biochem Biophys 2009; 485:41-8. [DOI: 10.1016/j.abb.2009.02.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 11/24/2022]
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Liu FC, Liao CH, Chang YW, Liou JT, Day YJ. Splitomicin suppresses human platelet aggregation via inhibition of cyclic AMP phosphodiesterase and intracellular Ca++ release. Thromb Res 2009; 124:199-207. [PMID: 19327818 DOI: 10.1016/j.thromres.2009.02.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 02/11/2009] [Accepted: 02/19/2009] [Indexed: 01/03/2023]
Abstract
Splitomicin is derived from beta-naphthol and is an inhibitor of Silent Information Regulator 2 (SIR2). Its naphthoic moiety might be responsible for its inhibitory effects on platelets. The major goal of our study was to examine possible mechanisms of action of splitomicin on platelet aggregation in order to promote development of a novel anti-platelet aggregation therapy for cardiovascular and cerebrovascular diseases. To study the inhibitory effects of splitomicin on platelet aggregation, we used washed human platelets, and monitored platelet aggregation and ATP release induced by thrombin (0.1 U/ml), collagen (2 microg/ml), arachidonic acid (AA) (0.5 mM), U46619 (2 microM) or ADP (10 microM). Splitomicin inhibited platelet aggregation induced by thrombin, collagen, AA and U46619 with a concentration dependent manner. Splitomicin increased cAMP and this effect was enhanced when splitomicin (150 microM) was combined with PGE1 (0.5 microM). It did not further increase cAMP when combined with IBMX. This data indicated that splitomicin increases cAMP by inhibiting activity of phosphodiestease. In addition, splitomicin (300 microM) attenuated intracellular Ca(++) mobilization, and production of thromboxane B2 (TXB2) in platelets that was induced by thrombin, collagen, AA or U46619. The inhibitory mechanism of splitomicin on platelet aggregation may increase cyclic AMP levels via inhibition of cyclic AMP phosphodiesterase activity and subsequent inhibition of intracellular Ca(++) mobilization, TXB2 formation and ATP release.
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Affiliation(s)
- Fu-Chao Liu
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou, Taiwan, ROC
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Hunter RW, Mackintosh C, Hers I. Protein kinase C-mediated phosphorylation and activation of PDE3A regulate cAMP levels in human platelets. J Biol Chem 2009; 284:12339-48. [PMID: 19261611 DOI: 10.1074/jbc.m807536200] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The elevation of [cAMP](i) is an important mechanism of platelet inhibition and is regulated by the opposing activity of adenylyl cyclase and phosphodiesterase (PDE). In this study, we demonstrate that a variety of platelet agonists, including thrombin, significantly enhance the activity of PDE3A in a phosphorylation-dependent manner. Stimulation of platelets with the PAR-1 agonist SFLLRN resulted in rapid and transient phosphorylation of PDE3A on Ser(312), Ser(428), Ser(438), Ser(465), and Ser(492), in parallel with the PKC (protein kinase C) substrate, pleckstrin. Furthermore, phosphorylation and activation of PDE3A required the activation of PKC, but not of PI3K/PKB, mTOR/p70S6K, or ERK/RSK. Activation of PKC by phorbol esters also resulted in phosphorylation of the same PDE3A sites in a PKC-dependent, PKB-independent manner. This was further supported by the finding that IGF-1, which strongly activates PI3K/PKB, but not PKC, did not regulate PDE3A. Platelet activation also led to a PKC-dependent association between PDE3A and 14-3-3 proteins. In contrast, cAMP-elevating agents such as PGE(1) and forskolin-induced phosphorylation of Ser(312) and increased PDE3A activity, but did not stimulate 14-3-3 binding. Finally, complete antagonism of PGE(1)-evoked cAMP accumulation by thrombin required both G(i) and PKC activation. Together, these results demonstrate that platelet activation stimulates PKC-dependent phosphorylation of PDE3A on Ser(312), Ser(428), Ser(438), Ser(465), and Ser(492) leading to a subsequent increase in cAMP hydrolysis and 14-3-3 binding.
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Affiliation(s)
- Roger W Hunter
- Department of Biochemistry, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, UK
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Ofosu FA, Dewar L, Song Y, Cedrone AC, Hortelano G, Craven SJ. Early Intraplatelet Signaling Enhances the Release of Human Platelet PAR-1 and -4 Amino-Terminal Peptides in Response to Thrombin. Biochemistry 2009; 48:1562-72. [DOI: 10.1021/bi801399c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Frederick A. Ofosu
- Department of Pathology and Molecular Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario L8N 3Z5, Canada
| | - Lori Dewar
- Department of Pathology and Molecular Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario L8N 3Z5, Canada
| | - Yingqi Song
- Department of Pathology and Molecular Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario L8N 3Z5, Canada
| | - Aisha C. Cedrone
- Department of Pathology and Molecular Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario L8N 3Z5, Canada
| | - Gonzalo Hortelano
- Department of Pathology and Molecular Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario L8N 3Z5, Canada
| | - Sharon J. Craven
- Department of Pathology and Molecular Medicine, McMaster University, and Canadian Blood Services, Hamilton, Ontario L8N 3Z5, Canada
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Liu FC, Liao CH, Chang YW, Liou JT, Day YJ. A new insight of anti-platelet effects of sirtinol in platelets aggregation via cyclic AMP phosphodiesterase. Biochem Pharmacol 2009; 77:1364-73. [PMID: 19426675 DOI: 10.1016/j.bcp.2009.01.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Revised: 01/15/2009] [Accepted: 01/20/2009] [Indexed: 12/21/2022]
Abstract
Sirtinol, a cell permeable six-membered lactone ring, is derived from naphthol and potent inhibitor of SIR2 and its naphtholic may have the inhibitory effects on platelets aggregation. In this study, platelet function was examined by collagen/epinephrine (CEPI) and collagen/ADP-induced closure times using the PFA-100 system reveal that CEPI-CT and CADP-CT were prolonged by sirtinol. The platelets aggregation regulated by physiological agonists such as: thrombin, collagen and AA and U46619 were significantly inhibited by sirtinol. Increases cAMP level was observed when sirtinol treated with Prostaglandin E1 in washed platelets. Moreover, sirtinol attenuated intracellular Ca(2+) release and thromboxane B2 formation stimulated by thrombin, collagen, AA and U46619 in human washed platelets. This study indicated that sirtinol could inhibit the platelet aggregation induced by physiological agonists, AA and U46619. The mechanism of action may include an increase of cAMP level with enhanced VASP-Ser157 phosphorylation via inhibition of cAMP phosphodiesterase activity and subsequent inhibition of intracellular Ca(2+) mobilization, thromboxane A2 formation, and ATP release during the platelet aggregation.
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Affiliation(s)
- Fu-Chao Liu
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou Taiwan, ROC
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50
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The critical roles of cyclic AMP/cyclic AMP-dependent protein kinase in platelet physiology. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/s11515-008-0098-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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