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Prognostic Value of Platelet to Lymphocyte Ratio in Sepsis: A Systematic Review and Meta-analysis. BIOMED RESEARCH INTERNATIONAL 2022; 2022:9056363. [PMID: 35707370 PMCID: PMC9192240 DOI: 10.1155/2022/9056363] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 05/10/2022] [Indexed: 12/27/2022]
Abstract
The goal of this study was to conduct a systematic review of the literature on the relationship between peripheral blood platelet to lymphocyte ratio (PLR) and mortality in sepsis and to integrate the findings in a meta-analysis. An electronic search of three main databases was performed: PubMed, Embase, and Scopus on 19 December 2021. Finally, 16 studies comprising 2403 septic patients, including 1249 survivors and 1154 nonsurvivors, were included in this meta-analysis. We found that PLR levels were significantly higher in nonsurvivors than in survivors (random effect model: SMD = 0.72, 95% CI; 0.35–1.10, p < 0.001). However, significant heterogeneity was observed across the studies (I2 = 94.1%, p < 0.01). So, we used random effect model in our meta-analysis. In the subgroup analysis, according to mortality time, patients deceased during one month after sepsis had elevated levels of PLR compared to survivors (SMD = 1.03, 95% CI = 0.15-1.92, p = 0.22). However, in-hospital mortality was not associated with PLR level (SMD = 0.41, 95% CI = −0.18-0.99, p = 0.175). Our findings support PLR to be a promising biomarker that can be readily integrated into clinical settings to aid in the prediction and prevention of sepsis mortality.
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2
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Wang CC, Wang LC, Yang KC, Chen MJ, Lin HC, Han YY. Enhancement of the anticoagulant capacity of polyvinyl chloride tubing for cardiopulmonary bypass circuit using aluminum oxide nanoscale coating applied through atomic layer deposition. J Biomed Mater Res B Appl Biomater 2021; 110:527-534. [PMID: 34492134 DOI: 10.1002/jbm.b.34932] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 08/11/2021] [Accepted: 08/22/2021] [Indexed: 12/13/2022]
Abstract
For cardiopulmonary bypass, the polyvinyl chloride (PVC) circuit which can initiate the activation of platelets and the coagulation cascade after blood cell contacting is the possible detrimental effect. Surface coating of the PVC tubing system can be an effective approach to enhance circuit's hemocompatibility. In this study, aluminum oxide (Al2 O3 ) thin films were deposited through thermal atomic layer deposition (T-ALD) or plasma-enhanced ALD (PE-ALD) on PVC samples, and the anticoagulation of the Al2 O3 -coated PVC samples was demonstrated. The results revealed that Al2 O3 deposition through ALD increased surface roughness, whereas T-ALD had a relative hydrophilicity compared with blank PVC and PE-ALD. Whole blood immersion tests showed that blood clots formed on blank PVC and that a large amount of red blood cells was found on PE-ALD substrates, whereas less blood cells were noted in T-ALD samples. Both T-ALD and PE-ALD Al2 O3 films did not cause activation of blood cells, as evidenced in CD3+ /CD4+ /CD8+ , CD61+ /CD62P+ , and CD45+ /CD42b+ populations. Analysis of serum coagulation factors showed that a lower amount of prothrombin was absorbed on T-ALD Al2 O3 samples than that on blank PVC. For albumin and fibrinogen immersion tests, immunostaining and scanning electron microscopy further revealed that a thin albumin layer was absorbed on T-ALD Al2 O3 substrates but not on PVC samples. This study revealed that deposition of Al2 O3 films by T-ALD can improve anticoagulation of the PVC tubing system.
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Affiliation(s)
- Chen-Chie Wang
- Department of Orthopedic Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan.,Department of Orthopedics, School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Li-Chun Wang
- Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan
| | - Kai-Chiang Yang
- Department of Orthopedic Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan.,School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
| | - Miin-Jang Chen
- Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan
| | - Hsin-Chih Lin
- Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan
| | - Yin-Yi Han
- Department of Traumatology, National Taiwan University Hospital, Taipei, Taiwan.,Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
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3
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Bosco O, Vizio B, Gruden G, Schiavello M, Lorenzati B, Cavallo-Perin P, Russo I, Montrucchio G, Lupia E. Thrombopoietin Contributes to Enhanced Platelet Activation in Patients with Type 1 Diabetes Mellitus. Int J Mol Sci 2021; 22:ijms22137032. [PMID: 34210000 PMCID: PMC8269076 DOI: 10.3390/ijms22137032] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 12/11/2022] Open
Abstract
Atherosclerotic cardiovascular disease is the major cause of morbidity and mortality in patients with type 1 diabetes mellitus (T1DM). Enhanced platelet reactivity is considered a main determinant of the increased atherothrombotic risk of diabetic patients. Thrombopoietin (THPO), a humoral growth factor able to stimulate megakaryocyte proliferation and differentiation, also modulates the response of mature platelets by enhancing both activation and binding to leukocytes in response to different agonists. Increased THPO levels have been reported in different clinical conditions characterized by a generalized pro-thrombotic state, from acute coronary syndromes to sepsis/septic shock, and associated with elevated indices of platelet activation. To investigate the potential contribution of elevated THPO levels in platelet activation in T1DM patients, we studied 28 T1DM patients and 28 healthy subjects. We measured plasma levels of THPO, as well as platelet-leukocyte binding, P-selectin, and THPO receptor (THPOR) platelet expression. The priming activity of plasma from diabetic patients or healthy subjects on platelet–leukocyte binding and the role of THPO on this effect was also studied in vitro. T1DM patients had higher circulating THPO levels and increased platelet–monocyte and platelet–granulocyte binding, as well as platelet P-selectin expression, compared to healthy subjects, whereas platelet expression of THPOR did not differ between the two groups. THPO concentrations correlated with platelet–leukocyte binding, as well as with fasting glucose and Hb1Ac. In vitro, plasma from diabetic patients, but not from healthy subjects, primed platelet–leukocyte binding and platelet P-selectin expression. Blocking THPO biological activity using a specific inhibitor prevented the priming effect induced by plasma from diabetic patients. In conclusion, augmented THPO may enhance platelet activation in patients with T1DM, potentially participating in increasing atherosclerotic risk.
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Affiliation(s)
- Ornella Bosco
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
| | - Barbara Vizio
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
| | - Gabriella Gruden
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
| | - Martina Schiavello
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
| | | | - Paolo Cavallo-Perin
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
| | - Isabella Russo
- Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy
- Correspondence: (I.R.); (G.M.); (E.L.)
| | - Giuseppe Montrucchio
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
- Correspondence: (I.R.); (G.M.); (E.L.)
| | - Enrico Lupia
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (O.B.); (B.V.); (G.G.); (M.S.); (P.C.-P.)
- Correspondence: (I.R.); (G.M.); (E.L.)
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4
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van Dijk WEM, Brandwijk ON, Heitink-Polle KMJ, Schutgens REG, van Galen KPM, Urbanus RT. Hemostatic changes by thrombopoietin-receptor agonists in immune thrombocytopenia patients. Blood Rev 2020; 47:100774. [PMID: 33213987 DOI: 10.1016/j.blre.2020.100774] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/02/2020] [Accepted: 11/04/2020] [Indexed: 01/08/2023]
Abstract
Thrombopoietin receptor agonist (TPO-RA) treatment increases the thrombosis rate in immune thrombocytopenia (ITP). We hypothesize that TPO-RAs influence platelet function, global and secondary hemostasis and/or fibrinolysis. A systematic review was performed. If possible, data were compared between responders (relevant increase in platelet count), and non-responders. Twelve observational studies with 305 patients were included (responders (127/150 (85%))). There were indications that TPO-RA treatment enhanced platelet function, with respect to platelet-monocyte aggregates, soluble P-selectin, GPVI expression, and adhesion under flow. Studies addressing global and secondary hemostasis and fibrinolysis were scarce. Overall, no changes were found during TPO-RA treatment, apart from an accelerated clot formation and conflicting data on levels of plasminogen activator inhibitor (PAI)-1. The parameters that increased have previously been associated with thrombosis in other patient groups, and might contribute to the increased rate of thrombosis observed in TPO-RA-treated ITP patients.
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Affiliation(s)
- Wobke E M van Dijk
- Department of Hematology, Van Creveldkliniek, University Medical Centre Utrecht, Postbox 85500, 3508 GA Utrecht, The Netherlands.
| | - Odila N Brandwijk
- Education Centre, University Medical Centre Utrecht, Utrecht University, Universiteitsweg 98, 3584 CG Utrecht, The Netherlands
| | - Katja M J Heitink-Polle
- Department of Hematology, Van Creveldkliniek, University Medical Centre Utrecht, Postbox 85500, 3508 GA Utrecht, The Netherlands
| | - Roger E G Schutgens
- Department of Hematology, Van Creveldkliniek, University Medical Centre Utrecht, Postbox 85500, 3508 GA Utrecht, The Netherlands.
| | - Karin P M van Galen
- Department of Hematology, Van Creveldkliniek, University Medical Centre Utrecht, Postbox 85500, 3508 GA Utrecht, The Netherlands.
| | - Rolf T Urbanus
- Department of Hematology, Van Creveldkliniek, University Medical Centre Utrecht, Postbox 85500, 3508 GA Utrecht, The Netherlands.
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5
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Korde A, Ahangari F, Haslip M, Zhang X, Liu Q, Cohn L, Gomez JL, Chupp G, Pober JS, Gonzalez A, Takyar SS. An endothelial microRNA-1-regulated network controls eosinophil trafficking in asthma and chronic rhinosinusitis. J Allergy Clin Immunol 2020; 145:550-562. [PMID: 32035607 DOI: 10.1016/j.jaci.2019.10.031] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 09/25/2019] [Accepted: 10/16/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND Airway eosinophilia is a prominent feature of asthma and chronic rhinosinusitis (CRS), and the endothelium plays a key role in eosinophil trafficking. To date, microRNA-1 (miR-1) is the only microRNA known to be regulated in the lung endothelium in asthma models. OBJECTIVE We sought to determine the role of endothelial miR-1 in allergic airway inflammation. METHODS We measured microRNA and mRNA expression using quantitative RT-PCR. We used ovalbumin and house dust mite models of asthma. Endothelium-specific overexpression of miR-1 was achieved through lentiviral vector delivery or induction of a transgene. Tissue eosinophilia was quantified by using Congo red and anti-eosinophil peroxidase staining. We measured eosinophil binding with a Sykes-Moore adhesion chamber. Target recruitment to RNA-induced silencing complex was assessed by using anti-Argonaute2 RNA immunoprecipitation. Surface P-selectin levels were measured by using flow cytometry. RESULTS Serum miR-1 levels had inverse correlations with sputum eosinophilia, airway obstruction, and number of hospitalizations in asthmatic patients and sinonasal tissue eosinophilia in patients with CRS. IL-13 stimulation decreased miR-1 levels in human lung endothelium. Endothelium-specific overexpression of miR-1 reduced airway eosinophilia and asthma phenotypes in murine models and inhibited IL-13-induced eosinophil binding to endothelial cells. miR-1 recruited P-selectin, thymic stromal lymphopoietin, eotaxin-3, and thrombopoietin receptor to the RNA-induced silencing complex; downregulated these genes in the lung endothelium; and reduced surface P-selectin levels in IL-13-stimulated endothelial cells. In our asthma and CRS cohorts, miR-1 levels correlated inversely with its target genes. CONCLUSION Endothelial miR-1 regulates eosinophil trafficking in the setting of allergic airway inflammation. miR-1 has therapeutic potential in asthmatic patients and patients with CRS.
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Affiliation(s)
- Asawari Korde
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn
| | - Farida Ahangari
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn
| | - Maria Haslip
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn; Yale School of Nursing, Orange, Conn
| | - Xuchen Zhang
- Department of Pathology, Yale School of Medicine, New Haven, Conn
| | - Qing Liu
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn
| | - Lauren Cohn
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn
| | - Jose L Gomez
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn
| | - Geoffrey Chupp
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn
| | - Jordan S Pober
- Department of Immunobiology, Yale School of Medicine, New Haven, Conn
| | | | - Shervin S Takyar
- Section of Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Conn.
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6
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Margraf A, Zarbock A. Platelets in Inflammation and Resolution. THE JOURNAL OF IMMUNOLOGY 2019; 203:2357-2367. [DOI: 10.4049/jimmunol.1900899] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/30/2019] [Indexed: 12/22/2022]
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7
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Mezger M, Nording H, Sauter R, Graf T, Heim C, von Bubnoff N, Ensminger SM, Langer HF. Platelets and Immune Responses During Thromboinflammation. Front Immunol 2019; 10:1731. [PMID: 31402914 PMCID: PMC6676797 DOI: 10.3389/fimmu.2019.01731] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 07/09/2019] [Indexed: 12/17/2022] Open
Abstract
Besides mediating hemostatic functions, platelets are increasingly recognized as important players of inflammation. Data from experiments in mice and men revealed various intersection points between thrombosis, hemostasis, and inflammation, which are addressed and discussed in this review in detail. One such example is the intrinsic coagulation cascade that is initiated after platelet activation thereby further propagating and re-enforcing wound healing or thrombus formation but also contributing to the pathophysiology of severe diseases. FXII of the intrinsic pathway connects platelet activation with the coagulation cascade during immune reactions. It can activate the contact system thereby either creating an inflammatory state or accelerating inflammation. Recent insights into platelet biology could show that platelets are equipped with complement receptors. Platelets are important for tissue remodeling after injury has been inflicted to the endothelial barrier and to the subendothelial tissue. Thus, platelets are increasingly recognized as more than just cells relevant for bleeding arrest. Future insights into platelet biology are to be expected. This research will potentially offer novel opportunities for therapeutic intervention in diseases featuring platelet abundance.
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Affiliation(s)
- Matthias Mezger
- University Hospital, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany
| | - Henry Nording
- University Hospital, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany.,DZHK (German Research Centre for Cardiovascular Research), Partner Site Hamburg/Lübeck/Kiel, Lübeck, Germany
| | - Reinhard Sauter
- University Hospital, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany
| | - Tobias Graf
- University Hospital, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany
| | - Christian Heim
- Department of Cardiac Surgery, University Hospital Erlangen, Erlangen, Germany
| | - Nikolas von Bubnoff
- Department of Hematology and Oncology, Medical Center, University of Schleswig-Holstein, Lübeck, Germany
| | - Stephan M Ensminger
- Department of Cardiac and Thoracic Vascular Surgery, University Heart Center Lübeck, Lübeck, Germany
| | - Harald F Langer
- University Hospital, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany.,DZHK (German Research Centre for Cardiovascular Research), Partner Site Hamburg/Lübeck/Kiel, Lübeck, Germany
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8
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Shimizu M, Konishi A, Nomura S. Examination of biomarker expressions in sepsis-related DIC patients. Int J Gen Med 2018; 11:353-361. [PMID: 30254480 PMCID: PMC6140747 DOI: 10.2147/ijgm.s173684] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Disseminated avascular coagulation (DIC) is the main cause of death among patients with sepsis. In particular, low platelet count is predictive of poor outcome. However, the significance of platelet activation in patients with sepsis-related DIC is poorly understood. To determine the characteristics of platelet-related abnormality in patients with sepsis-related DIC, we assessed the expression levels of several biomarkers. METHODS Plasma levels of biomarkers, including cytokines, chemokines, soluble selectins, platelet-derived microparticles (PDMPs), soluble vascular adhesion molecule 1, and high mobility group box protein 1 were measured by enzyme-linked immunosorbent assay at baseline and after 4, 7, 14, and 21 days of DIC treatment. RESULTS Differences in platelet activation and in the elevation of activated platelet-related PDMPs and of soluble P-selectin were seen between patients suffering from sepsis and hematologic malignancy with DIC. In addition, the elevation of interleukin (IL)-6 and thrombopoietin (TPO) was significant in sepsis patients with DIC. Furthermore, IL-6 and TPO promoted platelet activation in vitro. CONCLUSION Assessment of PDMPs, sP-selectin, IL-6, and TPO may be beneficial in the primary prevention of multi-organ failure in sepsis patients with DIC.
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Affiliation(s)
- Michiomi Shimizu
- First Department of Internal Medicine, Kansai Medical University, Hirakata, Japan,
| | - Akiko Konishi
- First Department of Internal Medicine, Kansai Medical University, Hirakata, Japan,
| | - Shosaku Nomura
- First Department of Internal Medicine, Kansai Medical University, Hirakata, Japan,
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9
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Greco E, Lupia E, Bosco O, Vizio B, Montrucchio G. Platelets and Multi-Organ Failure in Sepsis. Int J Mol Sci 2017; 18:ijms18102200. [PMID: 29053592 PMCID: PMC5666881 DOI: 10.3390/ijms18102200] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/13/2017] [Accepted: 10/17/2017] [Indexed: 12/11/2022] Open
Abstract
Platelets have received increasing attention for their role in the pathophysiology of infectious disease, inflammation, and immunity. In sepsis, a low platelet count is a well-known biomarker for disease severity and more recently authors have focused their attention on the active role of platelets in the pathogenesis of multi-organ failure. Septic shock is characterised by a dysregulated inflammatory response, which can impair the microcirculation and lead to organ injury. Being at the crossroads between the immune system, clotting cascade, and endothelial cells, platelets seem to be an appealing central mediator and possible therapeutic target in sepsis. This review focuses on the pathogenic role of platelets in septic organ dysfunction in humans and animal models.
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Affiliation(s)
- Elisabetta Greco
- Department of Medical Science, University of Turin, 10126 Turin, Italy.
| | - Enrico Lupia
- Department of Medical Science, University of Turin, 10126 Turin, Italy.
| | - Ornella Bosco
- Department of Medical Science, University of Turin, 10126 Turin, Italy.
| | - Barbara Vizio
- Department of Medical Science, University of Turin, 10126 Turin, Italy.
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10
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Larsen SB, Grove EL, Neergaard-Petersen S, Würtz M, Hvas AM, Kristensen SD. Thrombopoietin and platelet aggregation in patients with stable coronary artery disease. Platelets 2017; 28:822-824. [PMID: 28436258 DOI: 10.1080/09537104.2017.1296567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Thrombopoietin (TPO) may facilitate platelet activation and aggregation. However, data on the impact of TPO on platelet aggregation in patients with stable coronary artery disease (CAD) are scarce. We aimed to investigate associations between TPO and platelet aggregation and activation in patients with stable coronary artery disease (CAD). We studied 900 stable CAD patients. Serum TPO was assessed by ELISA. Platelet aggregation was evaluated using the Multiplate Analyzer (agonists: arachidonic acid [AA] and collagen) and the VerifyNow Aspirin Assay. Platelet activation was evaluated by soluble (s)P-selectin. Cyclooxygenase-1 inhibition was evaluated by serum thromboxane B2 (TXB2). We found that TPO correlated weakly with platelet aggregation evaluated by Multiplate using AA (r = -0.09, p = 0.01) and collagen as agonists (r = -0.03, p = 0.43) and by VerifyNow (r = 0.07, p = 0.03). We found no correlation between TPO and sP-selectin (r = -0.01, p = 0.70). Independent predictors of AA-induced platelet aggregation by Multiplate included high levels of sP-selectin and serum TXB2, high platelet count, increasing age and body mass index, female sex, and active smoking. Independent predictors of TPO included low AA-induced platelet aggregation by Multiplate, high levels of hs-CRP, active smoking, and high platelet aggregation evaluated by VerifyNow. In conclusion, TPO levels did not correlate with platelet activation and only weak associations were found between TPO and platelet aggregation, suggesting that TPO did not substantially facilitate platelet aggregation in stable CAD patients.
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Affiliation(s)
- Sanne Bøjet Larsen
- a Department of Cardiology , Aarhus University Hospital , Aarhus , Denmark
| | - Erik Lerkevang Grove
- a Department of Cardiology , Aarhus University Hospital , Aarhus , Denmark.,b Faculty of Health, Institute of Clinical Medicine , Aarhus University , Aarhus , Denmark
| | | | - Morten Würtz
- a Department of Cardiology , Aarhus University Hospital , Aarhus , Denmark
| | - Anne-Mette Hvas
- b Faculty of Health, Institute of Clinical Medicine , Aarhus University , Aarhus , Denmark.,c Department of Clinical Biochemistry , Aarhus University Hospital , Aarhus , Denmark
| | - Steen Dalby Kristensen
- a Department of Cardiology , Aarhus University Hospital , Aarhus , Denmark.,b Faculty of Health, Institute of Clinical Medicine , Aarhus University , Aarhus , Denmark
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Abstract
OBJECTIVES To study the concentrations of thrombopoietin (TPO), a growth factor recently involved in the pathogenesis of experimental acute pancreatitis (AP), and its potential role as an early diagnostic and prognostic biomarker in patients with AP. METHODS Thrombopoietin was measured in 44 AP patients, 18 patients with nonpancreatic acute abdominal pain, and 18 healthy volunteers. Acute pancreatitis severity was classified on the basis of the 2012 International Atlanta Symposium on Acute Pancreatitis criteria. RESULTS Thrombopoietin levels did not differ between AP patients and control subjects, whereas these were higher in patients with moderately severe or severe AP compared with those with mild AP. Receiver operating characteristic curve analysis of TPO for severe AP diagnosis showed an area under the curve of 0.80. A cutoff value of 31.48 pg/mL showed the highest sensitivity, allowing to rule out severe AP when TPO was lower, whereas TPO higher than 98.23 pg/mL was associated with severe AP with high specificity (93.5%). Furthermore, TPO levels were greater in AP patients developing organ dysfunction or sepsis and in nonsurvivors compared with survivors. CONCLUSIONS Our data provide the first evidence for TPO as potential early prognostic biomarker in AP patients. High TPO levels at hospital admission may predict organ dysfunction, sepsis, and fatal outcome in AP patients.
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12
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Immature platelet fraction predicts coagulopathy-related platelet consumption and mortality in patients with sepsis. Thromb Res 2016; 144:169-75. [DOI: 10.1016/j.thromres.2016.06.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/06/2016] [Accepted: 06/02/2016] [Indexed: 01/25/2023]
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13
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Blockade of Thrombopoietin Reduces Organ Damage in Experimental Endotoxemia and Polymicrobial Sepsis. PLoS One 2016; 11:e0151088. [PMID: 26963510 PMCID: PMC4786277 DOI: 10.1371/journal.pone.0151088] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 02/22/2016] [Indexed: 12/23/2022] Open
Abstract
Background and Purpose Thrombopoietin (TPO), a growth factor primarily involved in thrombopoiesis may also have a role in the pathophysiology of sepsis. In patients with sepsis, indeed, TPO levels are markedly increased, with disease severity being the major independent determinant of TPO concentrations. Moreover, TPO increases and correlates with ex vivo indices of platelet activation in patients with burn injury upon sepsis development, and may contribute to depress cardiac contractility in septic shock. Still, the role of TPO in sepsis pathophysiology remains controversial, given the protective role of TPO in other experimental disease models, for instance in doxorubicin-induced cardiotoxicity and myocardial ischemia/reperfusion injury. The aim of our study was to define the contribution of TPO in the development of organ damage induced by endotoxemia or sepsis, and to investigate the effects of inhibiting TPO in these conditions. Methods We synthesized a chimeric protein able to inhibit TPO, mTPOR-MBP, and studied its effect in two murine experimental models, acute endotoxemia and cecal ligation and puncture (CLP) model. Results In both models, TPO levels markedly increased, from 289.80±27.87 pg/mL to 465.60±45.92 pg/mL at 3 hours in the LPS model (P<0.01), and from 265.00±26.02 pg/mL to 373.70±26.20 pg/mL in the CLP model (P<0.05), respectively. Paralleling TPO levels, also platelet-monocyte aggregates increased, from 32.86±2.48% to 46.13±1.39% at 3 hours in the LPS model (P<0.01), and from 43.68±1.69% to 56.52±4.66% in the CLP model (P<0.05). Blockade of TPO by mTPOR-MBP administration reduced histological damage in target organs, namely lung, liver, and gut. In particular, neutrophil infiltration and lung septal thickening were reduced from a score of 1.86±0.34 to 0.60±0.27 (P<0.01) and from 1.43±0.37 to 0.40±0.16 (P<0.05), respectively, in the LPS model at 3 hours, and from a score of 1.75±0.37 to 0.38±0.18 (P<0.01) and from 1.25±0.31 to 0.13±0.13 (P<0.001), respectively, in the CLP model. Similarly, the number of hepatic microabscesses was decreased from 14.14±1.41 to 3.64±0.56 in the LPS model at 3 hours (P<0.001), and from 1.71±0.29 to 0.13±0.13 in the CLP model (P<0.001). Finally, the diameter of intestinal villi decreased from 90.69±3.95 μm to 70.74±3.60 μm in the LPS model at 3 hours (P<0.01), and from 74.29±4.29 μm to 57.50±1.89 μm in the CLP model (P<0.01). This protective effect was associated with the blunting of the increase in platelet-monocyte adhesion, and, on the contrary, with increased platelet-neutrophil aggregates in the circulation, which may be related to decreased neutrophil sequestration into the inflamed tissues. Conversely, circulating cytokine levels were not significantly changed, in both models, by mTPOR-MBP administration. Conclusion Our results demonstrate that TPO participates in the development of organ damage induced by experimental endotoxemia or polymicrobial sepsis via a mechanism involving increased platelet-leukocyte adhesion, but not cytokine release, and suggest that blocking TPO may be useful in preventing organ damage in patients affected by systemic inflammatory response or sepsis.
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Abbonante V, Di Buduo CA, Gruppi C, Malara A, Gianelli U, Celesti G, Anselmo A, Laghi L, Vercellino M, Visai L, Iurlo A, Moratti R, Barosi G, Rosti V, Balduini A. Thrombopoietin/TGF-β1 Loop Regulates Megakaryocyte Extracellular Matrix Component Synthesis. Stem Cells 2016; 34:1123-33. [PMID: 26748484 DOI: 10.1002/stem.2285] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 11/13/2015] [Accepted: 12/01/2015] [Indexed: 11/11/2022]
Abstract
Extracellular matrix (ECM) components initiate crucial biochemical and biomechanical cues that are required for bone marrow homeostasis. In our research, we prove that a peri-cellular matrix composed primarily of type III and type IV collagens, and fibronectin surrounds human megakaryocytes in the bone marrow. The data we collected support the hypothesis that bone marrow megakaryocytes possess a complete mechanism to synthesize the ECM components, and that thrombopoietin is a pivotal regulator of this new function inducing transforming growth factor-β1 (TGF-β1) release and consequent activation of the downstream pathways, both in vitro and in vivo. This activation results in a dose dependent increase of ECM component synthesis by megakaryocytes, which is reverted upon incubation with JAK and TGF-β1 receptor specific inhibitors. These data are pivotal for understanding the central role of megakaryocytes in creating their own regulatory niche within the bone marrow environment.
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Affiliation(s)
- Vittorio Abbonante
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Christian A Di Buduo
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Cristian Gruppi
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Alessandro Malara
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Umberto Gianelli
- Hematopathology Service, Division of Pathology, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Giuseppe Celesti
- Laboratory of Molecular Gastroenterology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | - Achille Anselmo
- Laboratory of Molecular Gastroenterology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | - Luigi Laghi
- Laboratory of Molecular Gastroenterology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | - Marco Vercellino
- Center for Tissue Engineering (CIT), INSTM UdR of Pavia, University of Pavia, Pavia, Italy.,Department of Occupational Medicine, Ergonomics and Disability, Salvatore Maugeri Foundation (FSM), Laboratory of Nanotechnology, Pavia, Italy
| | - Livia Visai
- Center for Tissue Engineering (CIT), INSTM UdR of Pavia, University of Pavia, Pavia, Italy.,Department of Occupational Medicine, Ergonomics and Disability, Salvatore Maugeri Foundation (FSM), Laboratory of Nanotechnology, Pavia, Italy
| | - Alessandra Iurlo
- Oncohematology of the Elderly Unit, Oncohematology Division, IRCCS Ca' Granda-Maggiore Policlinico Hospital Foundation, Milan, Italy
| | - Remigio Moratti
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Giovanni Barosi
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Vittorio Rosti
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Alessandra Balduini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy.,Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, USA
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Malara A, Abbonante V, Di Buduo CA, Tozzi L, Currao M, Balduini A. The secret life of a megakaryocyte: emerging roles in bone marrow homeostasis control. Cell Mol Life Sci 2015; 72:1517-36. [PMID: 25572292 PMCID: PMC4369169 DOI: 10.1007/s00018-014-1813-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 12/15/2014] [Accepted: 12/19/2014] [Indexed: 12/19/2022]
Abstract
Megakaryocytes are rare cells found in the bone marrow, responsible for the everyday production and release of millions of platelets into the bloodstream. Since the discovery and cloning, in 1994, of their principal humoral factor, thrombopoietin, and its receptor c-Mpl, many efforts have been directed to define the mechanisms underlying an efficient platelet production. However, more recently different studies have pointed out new roles for megakaryocytes as regulators of bone marrow homeostasis and physiology. In this review we discuss the interaction and the reciprocal regulation of megakaryocytes with the different cellular and extracellular components of the bone marrow environment. Finally, we provide evidence that these processes may concur to the reconstitution of the bone marrow environment after injury and their deregulation may lead to the development of a series of inherited or acquired pathologies.
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Affiliation(s)
- Alessandro Malara
- Department of Molecular Medicine, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Vittorio Abbonante
- Department of Molecular Medicine, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Christian A. Di Buduo
- Department of Molecular Medicine, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Lorenzo Tozzi
- Department of Molecular Medicine, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
- Department of Biomedical Engineering, Tufts University, Medford, MA USA
| | - Manuela Currao
- Department of Molecular Medicine, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
| | - Alessandra Balduini
- Department of Molecular Medicine, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
- Laboratory of Biotechnology, IRCCS San Matteo Foundation, Pavia, Italy
- Department of Biomedical Engineering, Tufts University, Medford, MA USA
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Lozano ML, Rivera J, Vicente V. Concentrados de plaquetas procedentes de sangre total (buffy coat) u obtenidos por aféresis; ¿qué producto emplear? Med Clin (Barc) 2012; 138:528-33. [DOI: 10.1016/j.medcli.2011.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 05/30/2011] [Accepted: 05/31/2011] [Indexed: 10/28/2022]
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17
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Thrombopoietin as biomarker and mediator of cardiovascular damage in critical diseases. Mediators Inflamm 2012; 2012:390892. [PMID: 22577249 PMCID: PMC3337636 DOI: 10.1155/2012/390892] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 02/01/2012] [Indexed: 02/07/2023] Open
Abstract
Thrombopoietin (TPO) is a humoral growth factor originally identified for its ability to stimulate the proliferation and differentiation of megakaryocytes. In addition to its actions on thrombopoiesis, TPO directly modulates the homeostatic potential of mature platelets by influencing their response to several stimuli. In particular, TPO does not induce platelet aggregation per se but is able to enhance platelet aggregation in response to different agonists (“priming effect”). Our research group was actively involved, in the last years, in characterizing the effects of TPO in several human critical diseases. In particular, we found that TPO enhances platelet activation and monocyte-platelet interaction in patients with unstable angina, chronic cigarette smokers, and patients with burn injury and burn injury complicated with sepsis. Moreover, we showed that TPO negatively modulates myocardial contractility by stimulating its receptor c-Mpl on cardiomyocytes and the subsequent production of NO, and it mediates the cardiodepressant activity exerted in vitro by serum of septic shock patients by cooperating with TNF-α and IL-1β.
This paper will summarize the most recent results obtained by our research group on the pathogenic role of elevated TPO levels in these diseases and discuss them together with other recently published important studies on this topic.
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A novel role of thrombopoietin as a physiological modulator of coronary flow. ACTA ACUST UNITED AC 2011; 167:5-8. [PMID: 21237210 DOI: 10.1016/j.regpep.2010.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 11/19/2010] [Accepted: 12/29/2010] [Indexed: 11/24/2022]
Abstract
Thrombopoietin (TPO) is known for its ability to stimulate platelet production. However, little is currently known whether TPO plays a physiological function in the heart. The potential vasodilatory role of TPO was tested on the isolated rat heart. The expression of TPO receptor (c-mpl) and the TPO-dependent eNOS phosphorylation (P(Ser1179)) were studied on Cardiac-derived normal Human Micro Vascular Endothelial Cells (HMVEC-C) by Western blot analysis. While TPO (10-200 pg/mL) did not modify coronary flow (CF) under basal conditions, it reduced the coronary constriction caused by endothelin-1 (ET-1; 10nM) in a dose-dependent manner. This effect was blocked by both Wortmannin (100 nM) and L-NAME (100 nM); on HMVEC-C, TPO induced eNOS phosphorylation through a Wortmannin sensitive mechanism. Taken together, our data suggest a potential role of TPO as a physiological regulator of CF. By acting on specific receptors present on endothelial cells, TPO may induce PI3K/Akt-dependent eNOS phosphorylation and NO release.
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G-CSF-mediated thrombopoietin release triggers neutrophil motility and mobilization from bone marrow via induction of Cxcr2 ligands. Blood 2011; 117:4349-57. [PMID: 21224471 DOI: 10.1182/blood-2010-09-308387] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Emergency mobilization of neutrophil granulocytes (neutrophils) from the bone marrow (BM) is a key event of early cellular immunity. The hematopoietic cytokine granulocyte-colony stimulating factor (G-CSF) stimulates this process, but it is unknown how individual neutrophils respond in situ. We show by intravital 2-photon microscopy that a systemic dose of human clinical-grade G-CSF rapidly induces the motility and entry of neutrophils into blood vessels within the tibial BM of mice. Simultaneously, the neutrophil-attracting chemokine KC (Cxcl1) spikes in the blood. In mice lacking the KC receptor Cxcr2, G-CSF fails to mobilize neutrophils and antibody blockade of Cxcr2 inhibits the mobilization and induction of neutrophil motility in the BM. KC is expressed by megakaryocytes and endothelial cells in situ and is released in vitro by megakaryocytes isolated directly from BM. This production of KC is strongly increased by thrombopoietin (TPO). Systemic G-CSF rapidly induces the increased production of TPO in BM. Accordingly, a single injection of TPO mobilizes neutrophils with kinetics similar to G-CSF, and mice lacking the TPO receptor show impaired neutrophil mobilization after short-term G-CSF administration. Thus, a network of signaling molecules, chemokines, and cells controls neutrophil release from the BM, and their mobilization involves rapidly induced Cxcr2-mediated motility controlled by TPO as a pacemaker.
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20
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Lupia E, Spatola T, Cuccurullo A, Bosco O, Mariano F, Pucci A, Ramella R, Alloatti G, Montrucchio G. Thrombopoietin modulates cardiac contractility in vitro and contributes to myocardial depressing activity of septic shock serum. Basic Res Cardiol 2010; 105:609-20. [PMID: 20467749 DOI: 10.1007/s00395-010-0103-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 04/16/2010] [Accepted: 04/19/2010] [Indexed: 01/21/2023]
Abstract
Thrombopoietin (TPO) is a humoral growth factor that has been shown to increase platelet activation in response to several agonists. Patients with sepsis have increased circulating TPO levels, which may enhance platelet activation, potentially participating to the pathogenesis of multi-organ failure. Aim of this study was to investigate whether TPO affects myocardial contractility and participates to depress cardiac function during sepsis. We showed the expression of the TPO receptor c-Mpl on myocardial cells and tissue by RT-PCR, immunofluorescence and western blotting. We then evaluated the effect of TPO on the contractile function of rat papillary muscle and isolated heart. TPO did not change myocardial contractility in basal conditions, but, when followed by epinephrine (EPI) stimulation, it blunted the enhancement of contractile force induced by EPI both in papillary muscle and isolated heart. An inhibitor of TPO prevented TPO effect on cardiac inotropy. Treatment of papillary muscle with pharmacological inhibitors of phosphatidylinositol 3-kinase, NO synthase, and guanilyl cyclase abolished TPO effect, indicating NO as the final mediator. We finally studied the role of TPO in the negative inotropic effect exerted by human septic shock (HSS) serum and TPO cooperation with TNF-alpha and IL-1beta. Pre-treatment with the TPO inhibitor prevented the decrease in contractile force induced by HSS serum. Moreover, TPO significantly amplified the negative inotropic effect induced by TNF-alpha and IL-1beta in papillary muscle. In conclusion, TPO negatively modulates cardiac inotropy in vitro and contributes to the myocardial depressing activity of septic shock serum.
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Affiliation(s)
- Enrico Lupia
- Department of Clinical Pathophysiology, University of Turin, Italy
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21
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Lupia E, Bosco O, Goffi A, Poletto C, Locatelli S, Spatola T, Cuccurullo A, Montrucchio G. Thrombopoietin contributes to enhanced platelet activation in cigarette smokers. Atherosclerosis 2010; 210:314-9. [DOI: 10.1016/j.atherosclerosis.2009.11.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 11/05/2009] [Accepted: 11/13/2009] [Indexed: 02/03/2023]
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22
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Schrezenmeier H, Seifried E. Buffy-coat-derived pooled platelet concentrates and apheresis platelet concentrates: which product type should be preferred? Vox Sang 2010; 99:1-15. [PMID: 20059760 DOI: 10.1111/j.1423-0410.2009.01295.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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23
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Erhardt JA, Erickson-Miller CL, Aivado M, Abboud M, Pillarisetti K, Toomey JR. Comparative analyses of the small molecule thrombopoietin receptor agonist eltrombopag and thrombopoietin on in vitro platelet function. Exp Hematol 2009; 37:1030-7. [PMID: 19631713 DOI: 10.1016/j.exphem.2009.06.011] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 06/22/2009] [Accepted: 06/24/2009] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The thrombopoietin receptor (TPOR) is a therapeutic target for treatment of thrombocytopenia because stimulation of this receptor results in enhanced megakaryocyte proliferation, differentiation, and ultimately platelet production. In addition to effects on megakaryocytes, TPOR stimulation also impacts platelet function. The present study examined platelet function following stimulation with the small molecule TPOR agonist eltrombopag. MATERIALS AND METHODS Platelets were obtained from healthy volunteers, and signal transduction pathway activation was examined in washed platelet preparations. Platelet aggregation was examined in both washed platelet preparations and platelet-rich plasma. Platelet alpha-granule release was determined via fluorescein-activated cell sorting measurement of CD62P. RESULTS In signal transduction studies of washed human platelets, eltrombopag induced the phosphorylation signal transducers and activators of transcription (STAT) proteins with no phosphorylation of Akt, whereas recombinant human TPO (rhTPO) induced the phosphorylation of Akt as well as STAT-1, -3, and -5. In studies conducted at subthreshold/submaximal concentrations of adenosine diphosphate (ADP) or collagen, eltrombopag pretreatment did not result in platelet aggregation. In contrast, rhTPO acted in synergy with submaximal concentrations of ADP or collagen to induce maximal aggregation under all conditions examined. Similarly, platelet activation as examined via surface expression of CD62P was not enhanced by eltrombopag pretreatment as compared to rhTPO. CONCLUSIONS These results demonstrate that the nonpeptidyl TPOR agonist eltrombopag stimulates platelet signal transduction with little or no effect on overall platelet function, in contrast to TPO, which significantly primes platelet activation. These data demonstrate that effects of TPOR ligands on platelet function can vary depending on the specific mechanism utilized to stimulate the TPOR.
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Affiliation(s)
- Joseph A Erhardt
- Department of Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA.
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Lupia E, Bosco O, Mariano F, Dondi AE, Goffi A, Spatola T, Cuccurullo A, Tizzani P, Brondino G, Stella M, Montrucchio G. Elevated thrombopoietin in plasma of burned patients without and with sepsis enhances platelet activation. J Thromb Haemost 2009; 7:1000-8. [PMID: 19317837 DOI: 10.1111/j.1538-7836.2009.03348.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Thrombopoietin (TPO) is a humoral growth factor that does not induce platelet aggregation per se, but enhances platelet activation in response to several agonists. Circulating levels of TPO are increased in patients with sepsis and are mainly related to sepsis severity. OBJECTIVES To investigate the potential contribution of elevated TPO levels in platelet activation during burn injury complicated or not by sepsis. METHODS We studied 22 burned patients, 10 without and 12 with sepsis, and 10 healthy subjects. We measured plasma levels of TPO, as well as leukocyte-platelet binding and P-selectin expression. The priming activity of plasma from burned patients or healthy subjects on platelet aggregation and leukocyte-platelet binding, and the role of TPO in these effects were also studied in vitro. RESULTS Burned patients without and with sepsis showed higher circulating TPO levels and increased monocyte-platelet binding compared with healthy subjects. Moreover, TPO levels, monocyte-platelet binding and P-selectin expression were significantly higher in burned patients with sepsis than in burned patients without sepsis. In vitro, plasma from burned patients without and with sepsis, but not from healthy subjects, primed platelet aggregation, monocyte-platelet binding and platelet P-selectin expression. The effect of plasma from burned patients with sepsis was significantly higher than that of plasma from burned patients without sepsis. An inhibitor of TPO prevented the priming effect of plasma from burned patients. CONCLUSIONS Increased TPO levels may enhance platelet activation during burn injury and sepsis, potentially participating in the pathogenesis of multi-organ failure in these diseases.
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Affiliation(s)
- E Lupia
- Department of Clinical Pathophysiology, University of Turin, Turin, Italy
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Involvement of platelet activation by P2Y12 receptor in the development of transplant arteriosclerosis in mice. Transplantation 2009; 87:660-7. [PMID: 19295309 DOI: 10.1097/tp.0b013e318196305a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Although activated platelets influence inflammation by intraplatelet mediators in transplantation, their mechanism of involvement in the progression of transplant arteriosclerosis has not yet been elucidated. We, therefore, investigated this question using P2Y12 receptor knockout (KO) mice, in which platelets cannot be aggregated by adenosine diphosphate stimulation. METHODS Carotid arteries from 129X1 mice were orthotopically transplanted into wild-type or KO mice in a minor antigen(s)-mismatched strain combination. No immunosuppression was used. Grafts were harvested at 7, 14, 28, and 56 days after transplantation for morphometry and immunohistology. Fluorescence-activated cell sorting and quantitative real-time reverse-transcriptase polymerase chain reaction were performed at 7 and 14 days after transplantation. RESULTS The intima/media ratio of grafts in KO mice was significantly reduced compared with wild-type mice at 14, 28, and 56 days after transplantation. Fluorescence-activated cell sorting analysis showed a significant reduction of platelet CD154 expression and platelet-leukocyte aggregates in KO mice at 14 days after transplantation. Additionally, levels of intercellular adhesion molecule-1 and CD40 mRNA, and numbers of intercellular adhesion molecule-1- or CD40-positive cells in the grafts were lower in KO mice at 7 and 14 days after transplantation. These reductions resulted in a significant attenuation of CD45-positive leukocytes adhering to the graft vessel wall in KO mice at 14 days after transplantation. CONCLUSION Diminished platelet function by P2Y12 receptor deficiency attenuates initiation and strongly inhibits progression of transplant arteriosclerosis in mice by diminishing adhesion molecule expression and leukocyte accumulation in the grafts during the early phase after transplantation.
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Lupia E, Bosco O, Bergerone S, Dondi AE, Goffi A, Oliaro E, Cordero M, Del Sorbo L, Trevi G, Montrucchio G. Thrombopoietin contributes to enhanced platelet activation in patients with unstable angina. J Am Coll Cardiol 2007; 48:2195-203. [PMID: 17161245 DOI: 10.1016/j.jacc.2006.04.106] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 04/14/2006] [Accepted: 04/17/2006] [Indexed: 12/11/2022]
Abstract
OBJECTIVES We sought to investigate the potential role of elevated levels of thrombopoietin (TPO) in platelet activation during unstable angina (UA). BACKGROUND Thrombopoietin is a humoral growth factor that does not induce platelet aggregation per se, but primes platelet activation in response to several agonists. No data concerning its contribution to platelet function abnormalities described in patients with UA are available. METHODS We studied 15 patients with UA and, as controls, 15 patients with stable angina (SA) and 15 healthy subjects. We measured TPO and C-reactive protein (CRP), as well as monocyte-platelet binding and the platelet expression of P-selectin and of the TPO receptor, c-Mpl. The priming activity of patient or control plasma on platelet aggregation and monocyte-platelet binding and the role of TPO in this effect also were studied. RESULTS Patients with UA showed higher circulating TPO levels, as well as increased monocyte-platelet binding, platelet P-selectin expression, and CRP levels, than those with SA and healthy control subjects. The UA patients also showed reduced platelet expression of the TPO receptor, c-Mpl. In vitro, the plasma from UA patients, but not from SA patients or healthy controls, primed platelet aggregation and monocyte-platelet binding, which were both reduced when an inhibitor of TPO was used. CONCLUSIONS Thrombopoietin may enhance platelet activation in the early phases of UA, potentially participating in the pathogenesis of acute coronary syndromes.
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Affiliation(s)
- Enrico Lupia
- Azienda Ospedaliera San Giovanni Battista-Molinette, Turin, Italy
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Othman M, Labelle A, Mazzetti I, Elbatarny HS, Lillicrap D. Adenovirus-induced thrombocytopenia: the role of von Willebrand factor and P-selectin in mediating accelerated platelet clearance. Blood 2006; 109:2832-9. [PMID: 17148587 DOI: 10.1182/blood-2006-06-032524] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AbstractThrombocytopenia has been consistently reported following the administration of adenoviral gene transfer vectors. The mechanism underlying this phenomenon is currently unknown. In this study, we have assessed the influence of von Willebrand Factor (VWF) and P-selectin on the clearance of platelets following adenovirus administration. In mice, thrombocytopenia occurs between 5 and 24 hours after adenovirus delivery. The virus activates platelets and induces platelet-leukocyte aggregate formation. There is an associated increase in platelet and leukocyte-derived microparticles. Adenovirus-induced endothelial cell activation was shown by VCAM-1 expression on virus-treated, cultured endothelial cells and by the release of ultra-large molecular weight multimers of VWF within 1 to 2 hours of virus administration with an accompanying elevation of endothelial microparticles. In contrast, VWF knockout (KO) mice did not show significant thrombocytopenia after adenovirus administration. We have also shown that adenovirus interferes with adhesion of platelets to a fibronectin-coated surface and flow cytometry revealed the presence of the Coxsackie adenovirus receptor on the platelet surface. We conclude that VWF and P-selectin are critically involved in a complex platelet-leukocyte-endothelial interplay, resulting in platelet activation and accelerated platelet clearance following adenovirus administration.
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Affiliation(s)
- Maha Othman
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada
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Abstract
BACKGROUND Earlier it was reported that metabolic arrest followed by incubation at 4 degrees C reduces the platelet (PLT) storage defect. Here it is reported that this treatment also reduces binding and phagocytosis by macrophages. STUDY DESIGN AND METHODS Phagocytosis of mepacrine-labeled PLTs by macrophages changes the latter into bright fluorescent particles easily detected by fluorescence-activated cell sorting. RESULTS In combination with conventional binding analysis it was found that binding to phorbol 12-myristate 13-acetate-matured THP-1 cells is primarily regulated by PLT P-selectin expression and phagocytosis by combined phosphatidylserine (PS) exposure and glycoprotein (GP) Ibalpha clustering. It was found that trapping of PLT Ca2+ and raising cAMP reduces phagocytosis by lowering PS exposure. Chilling of PLTs leads to an increase in binding and PS- and GPIbalpha-mediated phagocytosis. Prior depletion of PLT energy stores prevents this increase by preserving low Ca2+ concentration, PS exposure, and PS-mediated phagocytosis. CONCLUSION These data characterize the individual factors that control PLT binding and phagocytosis and might help to define conditions that improve the survival of stored PLTs after transfusion.
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Affiliation(s)
- Bahram A Badlou
- Thrombosis and Hemostasis Laboratory, Department of Hematology, University Medical Center Utrecht, the Netherlands
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29
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Badlou BA, Ijseldijk MJW, Smid WM, Akkerman JWN. Prolonged platelet preservation by transient metabolic suppression. Transfusion 2005; 45:214-22. [PMID: 15660830 DOI: 10.1111/j.1537-2995.2004.04022.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND In this study whether metabolic suppression can be used to preserve platelet (PLT) function during prolonged storage was investigated. STUDY DESIGN AND METHODS Washed human PLTs were incubated without glucose and with antimycin A to block energy generation. Metabolic suppressed PLTs (MSPs) were stored for 72 hours at different temperatures to find the optimal storage temperature. Controls were incubated with 5 mmol per L glucose and stored at 22 and 4 degrees C. RESULTS Following metabolic recovery with glucose, MSPs stored at 37, 22, and 4 degrees C showed an increase in basal P-selectin expression (PSE) reaching greater than 40 percent after about 2, 20, and 48 hours; a decrease in thrombin receptor-activating peptide SFLLRN (TRAP)-induced PSE inversely related to the increase in basal PSE; and a decrease in TRAP-induced aggregation reaching less than 30 percent after about 4, 24, and more than 72 hours. When compared with control suspensions, MSPs stored at 4 degrees C better preserved a low basal PSE and in addition showed a better adhesion to surface coated-von Willebrand factor and fibrinogen in a flow chamber. CONCLUSION Metabolic suppression before storage at 4 degrees C contributes to better preservation of PLT function.
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Affiliation(s)
- B A Badlou
- Thrombosis and Haemostasis Laboratory, Department of Haematology, University Medical Center Utrecht, the Netherlands
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30
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Abstract
Platelet dysfunction likely contributes to the pathophysiology of catastrophic hemorrhages in preterm neonates. In vitro studies have demonstrated that platelets of both term and preterm neonates are hyporesponsive to a variety of agonists. In contrast,template bleeding times of term neonates are shorter than those from adults. Very little is known about this and other tests of primary hemostasis in premature and sick neonates in the neonatal intensive care unit (NICU). This article covers the current knowledge of platelet function in preterm and term neonates and review show new agents (such as recombinant thrombopoietin and recombinant factor VIIa) may enhance neonatal platelet function.
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Affiliation(s)
- Matthew A Saxonhouse
- Division of Neonatology, Department of Pediatrics, University of Florida, College of Medicine, P.O. Box 100296, 1600 SW Archer Road, Gainesville, FL 32610, USA.
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31
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Hankins J, Naidu P, Rieman M, Wang W, Kaushansky K, Rodriguez-Galindo C. Thrombocytosis in an infant with high thrombopoietin concentrations. J Pediatr Hematol Oncol 2004; 26:142-5. [PMID: 14767209 DOI: 10.1097/00043426-200402000-00019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Patients with essential thrombocythemia (ET) usually have normal thrombopoietin (TPO) concentrations because of negative feedback from thrombocytosis. TPO mutations in familial ET cases result in increased translation efficiency with excessive TPO stimulation and thrombocytosis. The authors describe an infant with a high platelet count (1300 x 103/mm3) and an elevated TPO concentration who was successfully treated with anagrelide. Sequencing of TPO revealed no genetic cause. This case may represent a case of atypical ET in which thrombocytosis results from TPO stimulation rather than clonal proliferation. Measuring TPO concentrations may be warranted for children with unexplained extreme thrombocytosis.
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Affiliation(s)
- Jane Hankins
- Department of Hematology-Oncology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
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32
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Schattner M, Lazzari MA. Thrombopoietin (TPO) capable of inducing P-selectin expression independently of calcium movements or platelet aggregation. Biochem Biophys Res Commun 2002; 299:343. [PMID: 12445804 DOI: 10.1016/s0006-291x(02)02641-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M Schattner
- Department of Thrombosis and Hemostasis, National Academy of Medicine, CONICET Pacheco de Melo 3081, Buenos Aires, Argentina.
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