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Gremmel T, Frelinger AL, Michelson AD. Platelet Physiology. Semin Thromb Hemost 2024. [PMID: 38653463 DOI: 10.1055/s-0044-1786387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Platelets are the smallest blood cells, numbering 150 to 350 × 109/L in healthy individuals. The ability of activated platelets to adhere to an injured vessel wall and form aggregates was first described in the 19th century. Besides their long-established roles in thrombosis and hemostasis, platelets are increasingly recognized as pivotal players in numerous other pathophysiological processes including inflammation and atherogenesis, antimicrobial host defense, and tumor growth and metastasis. Consequently, profound knowledge of platelet structure and function is becoming more important in research and in many fields of modern medicine. This review provides an overview of platelet physiology focusing particularly on the structure, granules, surface glycoproteins, and activation pathways of platelets.
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Affiliation(s)
- Thomas Gremmel
- Division of Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
- Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria
- Institute of Cardiovascular Pharmacotherapy and Interventional Cardiology, Karl Landsteiner Society, St. Pölten, Austria
- Karl Landsteiner University of Health Sciences, Krems, Austria
- Department of Internal Medicine I, Cardiology and Intensive Care Medicine, Landesklinikum Mistelbach-Gänserndorf, Mistelbach, Austria
| | - Andrew L Frelinger
- Division of Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Alan D Michelson
- Division of Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
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2
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Zou J, Sun S, De Simone I, ten Cate H, de Groot PG, de Laat B, Roest M, Heemskerk JW, Swieringa F. Platelet Activation Pathways Controlling Reversible Integrin αIIbβ3 Activation. TH OPEN 2024; 8:e232-e242. [PMID: 38911141 PMCID: PMC11193594 DOI: 10.1055/s-0044-1786987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 04/12/2024] [Indexed: 06/25/2024] Open
Abstract
Background Agonist-induced platelet activation, with the integrin αIIbβ3 conformational change, is required for fibrinogen binding. This is considered reversible under specific conditions, allowing a second phase of platelet aggregation. The signaling pathways that differentiate between a permanent or transient activation state of platelets are poorly elucidated. Objective To explore platelet signaling mechanisms induced by the collagen receptor glycoprotein VI (GPVI) or by protease-activated receptors (PAR) for thrombin that regulate time-dependent αIIbβ3 activation. Methods Platelets were activated with collagen-related peptide (CRP, stimulating GPVI), thrombin receptor-activating peptides, or thrombin (stimulating PAR1 and/or 4). Integrin αIIbβ3 activation and P-selectin expression was assessed by two-color flow cytometry. Signaling pathway inhibitors were applied before or after agonist addition. Reversibility of platelet spreading was studied by microscopy. Results Platelet pretreatment with pharmacological inhibitors decreased GPVI- and PAR-induced integrin αIIbβ3 activation and P-selectin expression in the target order of protein kinase C (PKC) > glycogen synthase kinase 3 > β-arrestin > phosphatidylinositol-3-kinase. Posttreatment revealed secondary αIIbβ3 inactivation (not P-selectin expression), in the same order, but this reversibility was confined to CRP and PAR1 agonist. Combined inhibition of conventional and novel PKC isoforms was most effective for integrin closure. Pre- and posttreatment with ticagrelor, blocking the P2Y 12 adenosine diphosphate (ADP) receptor, enhanced αIIbβ3 inactivation. Spreading assays showed that PKC or P2Y 12 inhibition provoked a partial conversion from filopodia to a more discoid platelet shape. Conclusion PKC and autocrine ADP signaling contribute to persistent integrin αIIbβ3 activation in the order of PAR1/GPVI > PAR4 stimulation and hence to stabilized platelet aggregation. These findings are relevant for optimization of effective antiplatelet treatment.
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Affiliation(s)
- Jinmi Zou
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
- Department of Biochemistry and Internal Medicine, Maastricht University Medical Center + , Maastricht, The Netherlands
| | - Siyu Sun
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
- Department of Biochemistry and Internal Medicine, Maastricht University Medical Center + , Maastricht, The Netherlands
| | - Ilaria De Simone
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
| | - Hugo ten Cate
- Department of Biochemistry and Internal Medicine, Maastricht University Medical Center + , Maastricht, The Netherlands
| | - Philip G. de Groot
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
| | - Bas de Laat
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
| | - Mark Roest
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
| | - Johan W.M. Heemskerk
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
| | - Frauke Swieringa
- Platelet (patho)physiology, Synapse Research Institute, Maastricht, The Netherlands
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3
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Fernández-Infante C, Hernández-Cano L, Herranz Ó, Berrocal P, Sicilia-Navarro C, González-Porras JR, Bastida JM, Porras A, Guerrero C. Platelet C3G: a key player in vesicle exocytosis, spreading and clot retraction. Cell Mol Life Sci 2024; 81:84. [PMID: 38345631 PMCID: PMC10861696 DOI: 10.1007/s00018-023-05109-8] [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: 10/06/2023] [Revised: 12/22/2023] [Accepted: 12/23/2023] [Indexed: 02/15/2024]
Abstract
C3G is a Rap1 GEF that plays a pivotal role in platelet-mediated processes such as angiogenesis, tumor growth, and metastasis by modulating the platelet secretome. Here, we explore the mechanisms through which C3G governs platelet secretion. For this, we utilized animal models featuring either overexpression or deletion of C3G in platelets, as well as PC12 cell clones expressing C3G mutants. We found that C3G specifically regulates α-granule secretion via PKCδ, but it does not affect δ-granules or lysosomes. C3G activated RalA through a GEF-dependent mechanism, facilitating vesicle docking, while interfering with the formation of the trans-SNARE complex, thereby restricting vesicle fusion. Furthermore, C3G promotes the formation of lamellipodia during platelet spreading on specific substrates by enhancing actin polymerization via Src and Rac1-Arp2/3 pathways, but not Rap1. Consequently, C3G deletion in platelets favored kiss-and-run exocytosis. C3G also controlled granule secretion in PC12 cells, including pore formation. Additionally, C3G-deficient platelets exhibited reduced phosphatidylserine exposure, resulting in decreased thrombin generation, which along with defective actin polymerization and spreading, led to impaired clot retraction. In summary, platelet C3G plays a dual role by facilitating platelet spreading and clot retraction through the promotion of outside-in signaling while concurrently downregulating α-granule secretion by restricting granule fusion.
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Affiliation(s)
- Cristina Fernández-Infante
- Instituto de Biología Molecular y Celular del Cáncer (IMBCC), USAL-CSIC, Centro de Investigación del Cáncer, Campus Unamuno S/N, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - Luis Hernández-Cano
- Instituto de Biología Molecular y Celular del Cáncer (IMBCC), USAL-CSIC, Centro de Investigación del Cáncer, Campus Unamuno S/N, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - Óscar Herranz
- Instituto de Biología Molecular y Celular del Cáncer (IMBCC), USAL-CSIC, Centro de Investigación del Cáncer, Campus Unamuno S/N, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - Pablo Berrocal
- Instituto de Biología Molecular y Celular del Cáncer (IMBCC), USAL-CSIC, Centro de Investigación del Cáncer, Campus Unamuno S/N, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - Carmen Sicilia-Navarro
- Instituto de Biología Molecular y Celular del Cáncer (IMBCC), USAL-CSIC, Centro de Investigación del Cáncer, Campus Unamuno S/N, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - José Ramón González-Porras
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
- Servicio de Hematología, Hospital Universitario de Salamanca, Salamanca, Spain
| | - José María Bastida
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
- Servicio de Hematología, Hospital Universitario de Salamanca, Salamanca, Spain
| | - Almudena Porras
- Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, Madrid, Spain.
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain.
| | - Carmen Guerrero
- Instituto de Biología Molecular y Celular del Cáncer (IMBCC), USAL-CSIC, Centro de Investigación del Cáncer, Campus Unamuno S/N, Salamanca, Spain.
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain.
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain.
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Green JR, Mahalingaiah PKS, Gopalakrishnan SM, Liguori MJ, Mittelstadt SW, Blomme EAG, Van Vleet TR. Off-target pharmacological activity at various kinases: Potential functional and pathological side effects. J Pharmacol Toxicol Methods 2023; 123:107468. [PMID: 37553032 DOI: 10.1016/j.vascn.2023.107468] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 06/16/2023] [Accepted: 08/01/2023] [Indexed: 08/10/2023]
Abstract
In drug discovery, during the lead optimization and candidate characterization stages, novel small molecules are frequently evaluated in a battery of in vitro pharmacology assays to identify potential unintended, off-target interactions with various receptors, transporters, ion channels, and enzymes, including kinases. Furthermore, these screening panels may also provide utility at later stages of development to provide a mechanistic understanding of unexpected safety findings. Here, we present a compendium of the most likely functional and pathological outcomes associated with interaction(s) to a panel of 95 kinases based on an extensive curation of the scientific literature. This panel of kinases was designed by AbbVie based on safety-related data extracted from the literature, as well as from over 20 years of institutional knowledge generated from discovery efforts. For each kinase, the scientific literature was reviewed using online databases and the most often reported functional and pathological effects were summarized. This work should serve as a practical guide for small molecule drug discovery scientists and clinical investigators to predict and/or interpret adverse effects related to pharmacological interactions with these kinases.
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Affiliation(s)
- Jonathon R Green
- Departments of Preclinical Safety, AbbVie, 1 North Waukegan Road, North Chicago, IL 60064, United States.
| | | | - Sujatha M Gopalakrishnan
- Drug Discovery Science and Technology, AbbVie, 1 North Waukegan Road, North Chicago, IL 60064, United States
| | - Michael J Liguori
- Departments of Preclinical Safety, AbbVie, 1 North Waukegan Road, North Chicago, IL 60064, United States
| | - Scott W Mittelstadt
- Departments of Preclinical Safety, AbbVie, 1 North Waukegan Road, North Chicago, IL 60064, United States
| | - Eric A G Blomme
- Departments of Preclinical Safety, AbbVie, 1 North Waukegan Road, North Chicago, IL 60064, United States
| | - Terry R Van Vleet
- Departments of Preclinical Safety, AbbVie, 1 North Waukegan Road, North Chicago, IL 60064, United States
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Li X, Zhao K, Lu Y, Wang J, Yao W. Genetic Analysis of Platelet-Related Genes in Hepatocellular Carcinoma Reveals a Novel Prognostic Signature and Determines PRKCD as the Potential Molecular Bridge. Biol Proced Online 2022; 24:22. [PMID: 36463115 PMCID: PMC9719151 DOI: 10.1186/s12575-022-00185-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 11/23/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Hepatocellular carcinoma (HCC) belongs to a representative lethality gastrointestinal malignancy, and comprehensive management of HCC remains intractable at present on account of its invasive biological feature that is easy to relapse and early metastasis. The intimate connection between platelets and tumor progression has been widely reported, and platelet-related indicators are also used in the clinical practice of carcinoma. This work is designed to investigate the significance of platelet-related genes in the prognostic prediction of patients with HCC and their potential role in the cross-talk between HCC cells and platelets in the tumor microenvironment. METHODS By integrating the RNA-seq data and clinicopathological information of HCC patients, we extracted prognosis-associated platelet-related genes based on the univariate cox analysis and further established a relevant prognostic signature via the lasso cox regression analysis, and two independent HCC cohorts were used as external validation. Multiple bioinformatics methods were utilized to explore the underlying functional discrepancy between different risk groups classified by the risk model. And in vitro proliferation, invasion, and migration assays were conducted to investigate the effect of platelet stimulation on HCC cells' viability and motility, and flow cytometric analysis was exerted to demonstrate the influence of HCC cells on platelet activation. RESULTS A novel platelet-related risk model was developed and patients both in the training and testing cohorts were divided into distinct risk subgroups according to the median risk score. It was observed that the high-risk status was closely associated with poor prognosis and worse clinicopathological parameters. Meanwhile, an obvious discrepancy in the constitution of the immune microenvironment also indicated that distinct immune status might be a potential determinant affecting prognosis as well as immunotherapy reactiveness. Moreover, in vitro experiments demonstrated that PRKCD could act as a molecular bridge between tumor cells and platelets, which could either participate in regulating tumor malignant phenotype or mediating platelet activation. CONCLUSIONS In brief, this work reveals a novel platelet-related risk signature for prognostic evaluation of HCC patients and confirms that PRKCD is a key messenger in HCC cell-platelet interaction and plays a crucial role in mediating platelet-induced tumor progression.
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Affiliation(s)
- Xiangyu Li
- Department of Biliary and Pancreatic Surgery/Cancer Research Center Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Kai Zhao
- Department of Biliary and Pancreatic Surgery/Cancer Research Center Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Yun Lu
- Department of Biliary and Pancreatic Surgery/Cancer Research Center Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Jianming Wang
- Department of Biliary and Pancreatic Surgery/Cancer Research Center Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.
- Affiliated Tianyou Hospital, Wuhan University of Science & Technology, Wuhan, 430064, China.
| | - Wei Yao
- Department of Oncology Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.
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Reversible Platelet Integrin αIIbβ3 Activation and Thrombus Instability. Int J Mol Sci 2022; 23:ijms232012512. [PMID: 36293367 PMCID: PMC9604507 DOI: 10.3390/ijms232012512] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 11/28/2022] Open
Abstract
Integrin αIIbβ3 activation is essential for platelet aggregation and, accordingly, for hemostasis and arterial thrombosis. The αIIbβ3 integrin is highly expressed on platelets and requires an activation step for binding to fibrinogen, fibrin or von Willebrand factor (VWF). A current model assumes that the process of integrin activation relies on actomyosin force-dependent molecular changes from a bent-closed and extended-closed to an extended-open conformation. In this paper we review the pathways that point to a functional reversibility of platelet αIIbβ3 activation and transient aggregation. Furthermore, we refer to mouse models indicating that genetic defects that lead to reversible platelet aggregation can also cause instable thrombus formation. We discuss the platelet agonists and signaling pathways that lead to a transient binding of ligands to integrin αIIbβ3. Our analysis points to the (autocrine) ADP P2Y1 and P2Y12 receptor signaling via phosphoinositide 3-kinases and Akt as principal pathways linked to reversible integrin activation. Downstream signaling events by protein kinase C, CalDAG-GEFI and Rap1b have not been linked to transient integrin activation. Insight into the functional reversibility of integrin activation pathways will help to better understand the effects of antiplatelet agents.
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Jain K, Tyagi T, Du J, Hu X, Patell K, Martin KA, Hwa J. Unfolded Protein Response Differentially Modulates the Platelet Phenotype. Circ Res 2022; 131:290-307. [PMID: 35862006 PMCID: PMC9357223 DOI: 10.1161/circresaha.121.320530] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 07/06/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND Unfolded protein response (UPR) is a multifaceted signaling cascade that alleviates protein misfolding. Although well studied in nucleated cells, UPR in absence of transcriptional regulation has not been described. Intricately associated with cardiovascular diseases, platelets, despite being anucleate, respond rapidly to stressors in blood. We investigate the UPR in anucleate platelets and explore its role, if any, on platelet physiology and function. METHODS Human and mouse platelets were studied using a combination of ex vivo and in vivo experiments. Platelet lineage-specific knockout mice were generated independently for each of the 3 UPR pathways, PERK (protein kinase RNA [PKR]-like endoplasmic reticulum kinase), XBP1 (X-binding protein), and ATF6 (activating transcription factor 6). Diabetes patients were prospectively recruited, and platelets were evaluated for activation of UPR under chronic pathophysiological disease conditions. RESULTS Tunicamycin induced the IRE1α (inositol-requiring enzyme-1alpha)-XBP1 pathway in human and mouse platelets, while oxidative stress predominantly activated the PERK pathway. PERK deletion significantly increased platelet aggregation and apoptosis and phosphorylation of PLCγ2, PLCβ3, and p38 MAPK. Deficiency of XBP1 increased platelet aggregation, with higher PLCβ3 and PKCδ activation. ATF6 deletion mediated a relatively modest effect on platelet phenotype with increased PKA (protein kinase A). Platelets from diabetes patients exhibited a positive correlation between disease severity, platelet activation, and protein aggregation, with only IRE1α-XBP1 activation. Moreover, IRE1α inhibition increased platelet aggregation, while clinically approved chemical chaperone, sodium 4-phenylbutyrate reduced the platelet hyperactivation. CONCLUSIONS We show for the first time, that UPR activation occurs in platelets and can be independent of genomic regulation, with selective induction being specific to the source and severity of stress. Each UPR pathway plays a key role and can differentially modulate the platelet activation pathways and phenotype. Targeting the specific arms of UPR may provide a new antiplatelet strategy to mitigate thrombotic risk in diabetes and other cardiovascular diseases.
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Affiliation(s)
- Kanika Jain
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
| | - Tarun Tyagi
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
| | - Jing Du
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
| | - Xiaoyue Hu
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
| | - Kanchi Patell
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
| | - Kathleen A. Martin
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
| | - John Hwa
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Room 759, New Haven, CT 06511
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8
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Gu W, Qi J, Zhang S, Ding Y, Qiao J, Han Y. Inhibition of HIF prolyl hydroxylase modulates platelet function. Thromb Haemost 2022; 122:1693-1705. [PMID: 35477177 DOI: 10.1055/a-1837-7797] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Hypoxia-inducible factors-1α (HIF-1α) involves in redox reaction. Considering the role of reactive oxygen species (ROS) in platelet function, whether it regulates platelet function remains unclear. Using an inhibitor of HIF prolyl hydroxylase IOX-2, we intend to investigate its effect on platelet function. Human platelets were treated with IOX-2 (0, 10, 25, and 50 M) followed by analysis of platelet aggregation, granule secretion, receptor expression, platelet spreading or clot retraction. Additionally, IOX-2 (10 mg/kg) was injected intraperitoneally into mice to measure tail bleeding time and arterial thrombosis. IOX-2 significantly inhibited collagen-related peptide (CRP, 0.25 μg/ml) or thrombin (0.03 U/ml)-induced platelet aggregation and ATP release dose dependently without affecting P-selectin expression and the surface levels of glycoprotein (GP)Ib, GPVI or IIb3. In addition, IOX-2-treated platelets presented significantly decreased spreading on fibrinogen or collagen and clot retraction. Moreover, IOX-2 administration into mice significantly impaired the in vivo hemostatic function of platelets and arterial thrombus formation without affecting the number of circulating platelets and coagulation factor (FVIII and FIX). Further, IOX-2 significantly upregulated HIF-1 in platelets, decreased ROS generation and downregulated NOX1 expression. Finally, IOX-2 increased the phosphorylation level of VASP (Ser157/239), and inhibited the phosphorylation of p38 (Thr180/Tyr182), ERK1/2 (Thr202/Tyr204), AKT (Thr308/Ser473) and PKC (Thr505) in CRP- or thrombin-stimulated platelets. In conclusion, inhibition of HIF prolyl hydroxylase modulates platelet function and arterial thrombus formation, possibly through upregulation of HIF-1α expression and subsequent inhibition of ROS generation, indicating that HIF-1α might be a novel target for the treatment of thrombotic disorders.
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Limami Y, Senhaji N, Zaid N, Khalki L, Naya A, Hajjaj-Hassouni N, Jalali F, Oudghiri M, Zaid Y. PKC-Delta-Dependent Pathways Contribute to the Exacerbation of the Platelet Activity in Crohn's Disease. Semin Thromb Hemost 2021; 48:246-250. [PMID: 34749401 DOI: 10.1055/s-0041-1736571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Youness Limami
- Department of Biology, Faculty of Sciences Ain Chock, Immunology and Biodiversity Laboratory, Hassan II University, Casablanca.,Department of Medicine, Research Center of Abulcasis University of Health Sciences, Rabat, Morocco
| | - Nezha Senhaji
- Faculty of Medicine, Laboratory of Genetic and Molecular Pathology, Hassan II University, Casablanca, Morocco
| | - Nabil Zaid
- Department of Biology, Faculty of Sciences, Mohammed V University in Rabat, Rabat, Morocco
| | - Loubna Khalki
- Faculty of Medicine, Research Center, Mohammed VI University of Health Sciences (UM6SS), Casablanca, Morocco
| | - Abdallah Naya
- Department of Biology, Faculty of Sciences Ain Chock, Immunology and Biodiversity Laboratory, Hassan II University, Casablanca
| | | | - Farid Jalali
- Department of Gastroenterology, Saddleback Medical Group, Laguna Hills, California
| | - Mounia Oudghiri
- Department of Biology, Faculty of Sciences Ain Chock, Immunology and Biodiversity Laboratory, Hassan II University, Casablanca
| | - Younes Zaid
- Department of Biology, Faculty of Sciences Ain Chock, Immunology and Biodiversity Laboratory, Hassan II University, Casablanca.,Department of Medicine, Research Center of Abulcasis University of Health Sciences, Rabat, Morocco.,Department of Biology, Faculty of Sciences, Mohammed V University in Rabat, Rabat, Morocco
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10
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Wang L, Liu G, Wu N, Dai B, Han S, Liu Q, Huang F, Chen Z, Xu W, Xia D, Gao C. mTOR regulates GPVI-mediated platelet activation. J Transl Med 2021; 19:201. [PMID: 33971888 PMCID: PMC8111939 DOI: 10.1186/s12967-021-02756-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 02/16/2021] [Indexed: 11/10/2022] Open
Abstract
Background Due to mTOR (mammalian/mechanistic target of rapamycin) gene-loss mice die during embryonic development, the role of mTOR in platelets has not been evaluated using gene knockout technology. Methods A mouse model with megakaryocyte/platelet-specific deletion of mTOR was established, and be used to evaluate the role of mTOR in platelet activation and thrombus formation. Results mTOR−/− platelets were deficient in thrombus formation when grown on low-concentration collagen-coated surfaces; however, no deficiency in thrombus formation was observed when mTOR−/− platelets were perfused on higher concentration collagen-coated surfaces. In FeCl3-induced mouse mesenteric arteriole thrombosis models, wild-type (WT) and mTOR−/− mice displayed significantly different responses to low-extent injury with respect to the ratio of occluded mice, especially within the first 40 min. Additionally, mTOR−/− platelets displayed reduced aggregation and dense granule secretion (ATP release) in response to low doses of the glycoprotein VI (GPVI) agonist collagen related peptide (CRP) and the protease-activated receptor-4 (PAR4) agonist GYPGKF-NH2; these deficiencies were overcame by stimulation with higher concentration agonists, suggesting dose dependence of the response. At low doses of GPVI or PAR agonist, the activation of αIIbβ3 in mTOR−/− platelets was reduced. Moreover, stimulation of mTOR−/− platelets with low-dose CRP attenuated the phosphorylation of S6K1, S6 and Akt Ser473, and increased the phosphorylation of PKCδ Thr505 and PKCε Ser729. Using isoform-specific inhibitors of PKCs (δ, ɛ, and α/β), we established that PKCδ/ɛ, and especially PKCδ but not PKCα/β or PKCθ, may be involved in low-dose GPVI-mediated/mTOR-dependent signaling. Conclusion These observations indicate that mTOR plays an important role in GPVI-dependent platelet activation and thrombus formation.
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Affiliation(s)
- Longsheng Wang
- Chronic Disease Research Institute, Department of Nutrition and Food Hygiene, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Gang Liu
- Chronic Disease Research Institute, Department of Nutrition and Food Hygiene, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China.,Department of Pharmacology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, Guizhou, China
| | - Nannan Wu
- Chronic Disease Research Institute, Department of Nutrition and Food Hygiene, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Baiyun Dai
- Chronic Disease Research Institute, Department of Nutrition and Food Hygiene, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Shuang Han
- Chronic Disease Research Institute, Department of Nutrition and Food Hygiene, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Qiaoyun Liu
- Department of Toxicology, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Fang Huang
- Department of Toxicology, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Zhihua Chen
- Department of Respiratory Medicine, Second Affiliated Hospital, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China
| | - Weihong Xu
- Zhejiang Hospital, 12 Lingyin Road, Hangzhou, 310013, China
| | - Dajing Xia
- Department of Toxicology, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China
| | - Cunji Gao
- Chronic Disease Research Institute, Department of Nutrition and Food Hygiene, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, 310058, China. .,Blood Research Institute, Blood Center of Wisconsin, Milwaukee, Milwaukee, WI, 53201, USA.
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11
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Kostyak JC, Mauri B, Patel A, Dangelmaier C, Reddy H, Kunapuli SP. Phosphorylation of protein kinase Cδ Tyr311 positively regulates thromboxane generation in platelets. J Biol Chem 2021; 296:100720. [PMID: 33932405 PMCID: PMC8164046 DOI: 10.1016/j.jbc.2021.100720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/21/2021] [Accepted: 04/27/2021] [Indexed: 11/19/2022] Open
Abstract
Platelets are key mediators of physiological hemostasis and pathological thrombosis, whose function must be carefully balanced by signaling downstream of receptors such as protease-activated receptor (PAR)4. Protein kinase C (PKC) is known to regulate various aspects of platelet function. For instance, PKCδ is known to regulate dense granule secretion, which is important for platelet activation. However, the mechanism by which PKCδ regulates this process as well as other facets of platelet activity is unknown. We speculated that the way PKCδ regulates platelet function may be because of the phosphorylation of tyrosine residues on PKCδ. We investigated phosphorylation of PKCδ following glycoprotein VI-mediated and PAR4-mediated platelet activation and found that Y311 is selectively phosphorylated when PAR4 is activated in human platelets. Therefore, we generated PKCδ Y311F knock-in mice, which are viable and have no gross abnormalities. However, PKCδY311F mice have significantly enhanced tail-bleeding times compared with WT littermate controls, which means hemostasis is interrupted. Furthermore, PKCδY311F mice exhibit longer time to carotid artery occlusion compared with WT control using a ferric chloride in vivo thrombosis model, indicating that the phosphorylation of PKCδ Y311 is prothrombotic. Washed platelets from PKCδY311F mice have reduced reactivity after stimulation with a PAR-4 agonist indicating its importance in platelet signaling. The phenotype observed in Y311F mouse platelets is because of reduced thromboxane generation, as an inhibitor of thromboxane generation equalizes the PKCδY311F platelet response to that of WT. Therefore, phosphorylation of PKCδ on Y311 is important for regulation of platelet function and specifically thromboxane generation, which reinforces platelet activation.
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Affiliation(s)
- John C Kostyak
- Sol Sherry Thrombosis Research Center, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA
| | - Benjamin Mauri
- Sol Sherry Thrombosis Research Center, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA
| | - Akruti Patel
- Sol Sherry Thrombosis Research Center, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA
| | - Carol Dangelmaier
- Sol Sherry Thrombosis Research Center, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA
| | - Haritha Reddy
- Sol Sherry Thrombosis Research Center, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA
| | - Satya P Kunapuli
- Sol Sherry Thrombosis Research Center, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA; Department of Physiology, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA; Department of Pharmacology, Temple University School Lewis M Katz School of Medicine, Philadelphia, Pennsylvania, USA.
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12
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Ether lipid metabolism by AADACL1 regulates platelet function and thrombosis. Blood Adv 2020; 3:3818-3828. [PMID: 31770438 DOI: 10.1182/bloodadvances.2018030767] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 09/28/2019] [Indexed: 12/25/2022] Open
Abstract
We previously reported the discovery of a novel lipid deacetylase in platelets, arylacetamide deacetylase-like 1 (AADACL1/NCEH1), and that its inhibition impairs agonist-induced platelet aggregation, Rap1 GTP loading, protein kinase C (PKC) activation, and ex vivo thrombus growth. However, precise mechanisms by which AADACL1 impacts platelet signaling and function in vivo are currently unknown. Here, we demonstrate that AADACL1 regulates the accumulation of ether lipids that impact PKC signaling networks crucial for platelet activation in vitro and in vivo. Human platelets treated with the AADACL1 inhibitor JW480 or the AADACL1 substrate 1-O-hexadecyl-2-acetyl-sn-glycerol (HAG) exhibited decreased platelet aggregation, granule secretion, Ca2+ flux, and PKC phosphorylation. Decreased aggregation and secretion were rescued by exogenous adenosine 5'-diphosphate, indicating that AADACL1 likely functions to induce dense granule secretion. Experiments with P2Y12-/- and CalDAG GEFI-/- mice revealed that the P2Y12 pathway is the predominate target of HAG-mediated inhibition of platelet aggregation. HAG itself displayed weak agonist properties and likely mediates its inhibitory effects via conversion to a phosphorylated metabolite, HAGP, which directly interacted with the C1a domains of 2 distinct PKC isoforms and blocked PKC kinase activity in vitro. Finally, AADACL1 inhibition in rats reduced platelet aggregation, protected against FeCl3-induced arterial thrombosis, and delayed tail bleeding time. In summary, our data support a model whereby AADACL1 inhibition shifts the platelet ether lipidome to an inhibitory axis of HAGP accumulation that impairs PKC activation, granule secretion, and recruitment of platelets to sites of vascular damage.
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Chaudhary PK, Kim S, Jee Y, Lee SH, Kim S. Characterization of Integrin αIIbβ3-Mediated Outside-in Signaling by Protein Kinase Cδ in Platelets. Int J Mol Sci 2020; 21:ijms21186563. [PMID: 32911704 PMCID: PMC7555476 DOI: 10.3390/ijms21186563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/01/2020] [Accepted: 09/07/2020] [Indexed: 11/16/2022] Open
Abstract
Engagement of integrin αIIbβ3 promotes platelet-platelet interaction and stimulates outside-in signaling that amplifies activation. Protein kinase Cδ (PKCδ) is known to play an important role in platelet activation, but its role in outside-in signaling has not been established. In the present study, we determined the role of PKCδ and its signaling pathways in integrin αIIbβ3-mediated outside-in signaling in platelets using PKCδ-deficient platelets. Platelet spreading to immobilized fibrinogen resulted in PKCδ phosphorylation, suggesting that αIIbβ3 activation caused PKCδ activation. αIIbβ3-mediated phosphorylation of Akt was significantly inhibited in PKCδ -/- platelets, indicating a role of PKCδ in outside-in signaling. αIIbβ3-mediated PKCδ phosphorylation was inhibited by proline-rich tyrosine kinase 2 (Pyk2) selective inhibitor, suggesting that Pyk2 contributes to the regulation of PKCδ phosphorylation in outside-in signaling. Additionally, Src-family kinase inhibitor PP2 inhibited integrin-mediated Pyk2 and PKCδ phosphorylation. Lastly, platelet spreading was inhibited in PKCδ -/- platelets compared to the wild-type (WT) platelets, and clot retraction from PKCδ -/- platelets was markedly delayed, indicating that PKCδ is involved in the regulation of αIIbβ3-dependent interactivities with cytoskeleton elements. Together, these results provide evidence that PKCδ plays an important role in outside-in signaling, which is regulated by Pyk2 in platelets.
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Affiliation(s)
- Preeti Kumari Chaudhary
- College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea; (P.K.C.); (S.K.); (S.-H.L.)
| | - Sanggu Kim
- College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea; (P.K.C.); (S.K.); (S.-H.L.)
| | - Youngheun Jee
- College of Veterinary Medicine and Veterinary Medical Research Institute, Jeju National University, Jeju 63243, Korea;
| | - Seung-Hun Lee
- College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea; (P.K.C.); (S.K.); (S.-H.L.)
| | - Soochong Kim
- College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea; (P.K.C.); (S.K.); (S.-H.L.)
- Correspondence: ; Tel.: +82-43-249-1846
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14
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Protein Kinase C-Delta (PKCδ) Tyrosine Phosphorylation is a Critical Regulator of Neutrophil-Endothelial Cell Interaction in Inflammation. Shock 2020; 51:538-547. [PMID: 30095599 DOI: 10.1097/shk.0000000000001247] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Neutrophil dysfunction plays an important role in inflammation-induced tissue injury. Previously, we identified protein kinase C-δ (PKCδ) as a critical controller of neutrophil activation and trafficking but how PKCδ is regulated in inflammation has not been delineated. PKCδ activity is regulated by tyrosine phosphorylation on multiple sites. Tyrosine155 is a key regulator of apoptosis and gene expression, but its role in proinflammatory signaling is not known. METHODS In-vitro studies - superoxide anion (O2) and neutrophil extracellular traps (NETs) were measured in bone marrow neutrophils (BMN) isolated from wild type (WT) and PKCδY155F knock-in mice (PKCδ tyrosine 155 → phenylalanine). Our novel 3D biomimetic microfluidic assay (bMFA) was used to delineate PKCδ-mediated regulation of individual steps in neutrophil adhesion and migration using WT and PKCδY155F BMN and mouse lung microvascular endothelial cells (MLMVEC). In-vivo studies - WT and PKCδY155F knock-in mice underwent sham or cecal ligation and puncture surgery and the lungs harvested 24 h post-surgery. RESULTS In vitro - PKCδY155F BMN had significantly reduced O2 and NETs release compared with WT. WT BMN, but not PKCδY155F BMN, demonstrated significant adhesion and migration across tumor necrosis factor-activated MLMVEC in bMFA. PKCδ inhibition significantly reduced WT BMN adhesion and migration under low shear and near bifurcations, but had no effect on PKCδY155F BMN. In vivo - mutation of PKCδ tyrosine 155 significantly decreased neutrophil migration into the lungs of septic mice. CONCLUSIONS PKCδ tyrosine 155 is a key phosphorylation site controlling proinflammatory signaling and neutrophil-endothelial cell interactions. These studies provide mechanistic insights into PKCδ regulation during inflammation.
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15
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Abstract
Phosphatidylinositol 3-kinase is an important signaling molecule that, once activated, leads to the generation of phosphatidylinositol (3,4,5)-trisphosphate (PIP3). We performed a proteomic screen to identify PIP3-interacting proteins in human platelets. Among these proteins, we found engulfment and cell motility 1 (ELMO1), a scaffold protein with no catalytic activity. ELMO1 is expressed in platelets and interacts with active RhoG. However, the function of ELMO1 in platelets is not known. The focus of this study was to determine the function of ELMO1 in platelets utilizing ELMO1-/- mice. Platelet aggregation, granule secretion, integrin αIIbβ3 activation, and thromboxane generation were enhanced in ELMO1-/- platelets in response to glycoprotein VI (GPVI) agonists but unaltered when a protease-activated receptor 4 agonist was used. The kinetics of spreading on immobilized fibrinogen was enhanced in ELMO1-/- platelets compared with wild-type (WT) littermate controls. This suggests that ELMO1 plays a role downstream of the GPVI and integrin αIIbβ3 pathway. Furthermore, whole blood from ELMO1-/- mice perfused over collagen exhibited enhanced thrombus formation compared with WT littermate controls. ELMO1-/- mice showed reduced survival compared with control following pulmonary embolism. ELMO1-/- mice also exhibited a shorter time to occlusion using the ferric-chloride injury model and reduced bleeding times compared with WT littermate controls. These results indicate that ELMO1 plays an important role in hemostasis and thrombosis in vivo. RhoG activity was enhanced in ELMO1-/- murine platelets compared with WT littermate controls in response to GPVI agonist. Together, these data suggest that ELMO1 negatively regulates GPVI-mediated thrombus formation via RhoG.
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16
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Nagy M, van Geffen JP, Stegner D, Adams DJ, Braun A, de Witt SM, Elvers M, Geer MJ, Kuijpers MJE, Kunzelmann K, Mori J, Oury C, Pircher J, Pleines I, Poole AW, Senis YA, Verdoold R, Weber C, Nieswandt B, Heemskerk JWM, Baaten CCFMJ. Comparative Analysis of Microfluidics Thrombus Formation in Multiple Genetically Modified Mice: Link to Thrombosis and Hemostasis. Front Cardiovasc Med 2019; 6:99. [PMID: 31417909 PMCID: PMC6682619 DOI: 10.3389/fcvm.2019.00099] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/03/2019] [Indexed: 12/15/2022] Open
Abstract
Genetically modified mice are indispensable for establishing the roles of platelets in arterial thrombosis and hemostasis. Microfluidics assays using anticoagulated whole blood are commonly used as integrative proxy tests for platelet function in mice. In the present study, we quantified the changes in collagen-dependent thrombus formation for 38 different strains of (genetically) modified mice, all measured with the same microfluidics chamber. The mice included were deficient in platelet receptors, protein kinases or phosphatases, small GTPases or other signaling or scaffold proteins. By standardized re-analysis of high-resolution microscopic images, detailed information was obtained on altered platelet adhesion, aggregation and/or activation. For a subset of 11 mouse strains, these platelet functions were further evaluated in rhodocytin- and laminin-dependent thrombus formation, thus allowing a comparison of glycoprotein VI (GPVI), C-type lectin-like receptor 2 (CLEC2) and integrin α6β1 pathways. High homogeneity was found between wild-type mice datasets concerning adhesion and aggregation parameters. Quantitative comparison for the 38 modified mouse strains resulted in a matrix visualizing the impact of the respective (genetic) deficiency on thrombus formation with detailed insight into the type and extent of altered thrombus signatures. Network analysis revealed strong clusters of genes involved in GPVI signaling and Ca2+ homeostasis. The majority of mice demonstrating an antithrombotic phenotype in vivo displayed with a larger or smaller reduction in multi-parameter analysis of collagen-dependent thrombus formation in vitro. Remarkably, in only approximately half of the mouse strains that displayed reduced arterial thrombosis in vivo, this was accompanied by impaired hemostasis. This was also reflected by comparing in vitro thrombus formation (by microfluidics) with alterations in in vivo bleeding time. In conclusion, the presently developed multi-parameter analysis of thrombus formation using microfluidics can be used to: (i) determine the severity of platelet abnormalities; (ii) distinguish between altered platelet adhesion, aggregation and activation; and (iii) elucidate both collagen and non-collagen dependent alterations of thrombus formation. This approach may thereby aid in the better understanding and better assessment of genetic variation that affect in vivo arterial thrombosis and hemostasis.
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Affiliation(s)
- Magdolna Nagy
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Johanna P van Geffen
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - David Stegner
- Rudolf Virchow Center, Institute of Experimental Biomedicine, University Hospital Würzburg, University of Würzburg, Würzburg, Germany
| | - David J Adams
- Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Attila Braun
- Rudolf Virchow Center, Institute of Experimental Biomedicine, University Hospital Würzburg, University of Würzburg, Würzburg, Germany
| | - Susanne M de Witt
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Margitta Elvers
- Department of Vascular Surgery, Experimental Vascular Medicine, Heinrich Heine University, Düsseldorf, Germany
| | - Mitchell J Geer
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Marijke J E Kuijpers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Karl Kunzelmann
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Jun Mori
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Cécile Oury
- GIGA-Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Joachim Pircher
- Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Ludwig-Maximilians-University, and DZHK (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany
| | - Irina Pleines
- Rudolf Virchow Center, Institute of Experimental Biomedicine, University Hospital Würzburg, University of Würzburg, Würzburg, Germany
| | - Alastair W Poole
- Department of Physiology and Pharmacology, School of Medical Sciences, University of Bristol, Bristol, United Kingdom
| | - Yotis A Senis
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Remco Verdoold
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Christian Weber
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands.,Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-Universität München, Munich, Germany
| | - Bernhard Nieswandt
- Rudolf Virchow Center, Institute of Experimental Biomedicine, University Hospital Würzburg, University of Würzburg, Würzburg, Germany
| | - Johan W M Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Constance C F M J Baaten
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands.,Institute for Molecular Cardiovascular Research (IMCAR), University Hospital Aachen, Aachen, Germany
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17
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Huang J, Li X, Shi X, Zhu M, Wang J, Huang S, Huang X, Wang H, Li L, Deng H, Zhou Y, Mao J, Long Z, Ma Z, Ye W, Pan J, Xi X, Jin J. Platelet integrin αIIbβ3: signal transduction, regulation, and its therapeutic targeting. J Hematol Oncol 2019; 12:26. [PMID: 30845955 PMCID: PMC6407232 DOI: 10.1186/s13045-019-0709-6] [Citation(s) in RCA: 208] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 02/21/2019] [Indexed: 12/18/2022] Open
Abstract
Integrins are a family of transmembrane glycoprotein signaling receptors that can transmit bioinformation bidirectionally across the plasma membrane. Integrin αIIbβ3 is expressed at a high level in platelets and their progenitors, where it plays a central role in platelet functions, hemostasis, and arterial thrombosis. Integrin αIIbβ3 also participates in cancer progression, such as tumor cell proliferation and metastasis. In resting platelets, integrin αIIbβ3 adopts an inactive conformation. Upon agonist stimulation, the transduction of inside-out signals leads integrin αIIbβ3 to switch from a low- to high-affinity state for fibrinogen and other ligands. Ligand binding causes integrin clustering and subsequently promotes outside-in signaling, which initiates and amplifies a range of cellular events to drive essential platelet functions such as spreading, aggregation, clot retraction, and thrombus consolidation. Regulation of the bidirectional signaling of integrin αIIbβ3 requires the involvement of numerous interacting proteins, which associate with the cytoplasmic tails of αIIbβ3 in particular. Integrin αIIbβ3 and its signaling pathways are considered promising targets for antithrombotic therapy. This review describes the bidirectional signal transduction of integrin αIIbβ3 in platelets, as well as the proteins responsible for its regulation and therapeutic agents that target integrin αIIbβ3 and its signaling pathways.
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Affiliation(s)
- Jiansong Huang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xia Li
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiaofeng Shi
- Department of Hematology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Mark Zhu
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jinghan Wang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Shujuan Huang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xin Huang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Huafeng Wang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Department of Hematological Malignancies Translational Science, Gehr Family Center for Leukemia Research, Hematologic Malignancies and Stem Cell Transplantation Institute, Beckman Research Institute, City of Hope Medical Center, Duarte, CA, 91010, USA
| | - Ling Li
- Department of Hematological Malignancies Translational Science, Gehr Family Center for Leukemia Research, Hematologic Malignancies and Stem Cell Transplantation Institute, Beckman Research Institute, City of Hope Medical Center, Duarte, CA, 91010, USA
| | - Huan Deng
- Department of Pathology, The Fourth Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Yulan Zhou
- Department of Hematology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Jianhua Mao
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Collaborative Innovation Center of Hematology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Sino-French Research Centre for Life Sciences and Genomics, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhangbiao Long
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhixin Ma
- Clinical Prenatal Diagnosis Center, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Wenle Ye
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jiajia Pan
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China.,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiaodong Xi
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Collaborative Innovation Center of Hematology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China. .,Sino-French Research Centre for Life Sciences and Genomics, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Jie Jin
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China. .,Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China. .,Institute of Hematology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
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19
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Tang Y, Soroush F, Sun S, Liverani E, Langston JC, Yang Q, Kilpatrick LE, Kiani MF. Protein kinase C-delta inhibition protects blood-brain barrier from sepsis-induced vascular damage. J Neuroinflammation 2018; 15:309. [PMID: 30400800 PMCID: PMC6220469 DOI: 10.1186/s12974-018-1342-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 10/22/2018] [Indexed: 12/21/2022] Open
Abstract
Background Neuroinflammation often develops in sepsis leading to activation of cerebral endothelium, increased permeability of the blood-brain barrier (BBB), and neutrophil infiltration. We have identified protein kinase C-delta (PKCδ) as a critical regulator of the inflammatory response and demonstrated that pharmacologic inhibition of PKCδ by a peptide inhibitor (PKCδ-i) protected endothelial cells, decreased sepsis-mediated neutrophil influx into the lung, and prevented tissue damage. The objective of this study was to elucidate the regulation and relative contribution of PKCδ in the control of individual steps in neuroinflammation during sepsis. Methods The role of PKCδ in mediating human brain microvascular endothelial (HBMVEC) permeability, junctional protein expression, and leukocyte adhesion and migration was investigated in vitro using our novel BBB on-a-chip (B3C) microfluidic assay and in vivo in a rat model of sepsis induced by cecal ligation and puncture (CLP). HBMVEC were cultured under flow in the vascular channels of B3C. Confocal imaging and staining were used to confirm tight junction and lumen formation. Confluent HBMVEC were pretreated with TNF-α (10 U/ml) for 4 h in the absence or presence of PKCδ-i (5 μM) to quantify neutrophil adhesion and migration in the B3C. Permeability was measured using a 40-kDa fluorescent dextran in vitro and Evans blue dye in vivo. Results During sepsis, PKCδ is activated in the rat brain resulting in membrane translocation, a step that is attenuated by treatment with PKCδ-i. Similarly, TNF-α-mediated activation of PKCδ and its translocation in HBMVEC are attenuated by PKCδ-i in vitro. PKCδ inhibition significantly reduced TNF-α-mediated hyperpermeability and TEER decrease in vitro in activated HBMVEC and rat brain in vivo 24 h after CLP induced sepsis. TNF-α-treated HBMVEC showed interrupted tight junction expression, whereas continuous expression of tight junction protein was observed in non-treated or PKCδ-i-treated cells. PKCδ inhibition also reduced TNF-α-mediated neutrophil adhesion and migration across HBMVEC in B3C. Interestingly, while PKCδ inhibition decreased the number of adherent neutrophils to baseline (no-treatment group), it significantly reduced the number of migrated neutrophils below the baseline, suggesting a critical role of PKCδ in regulating neutrophil transmigration. Conclusions The BBB on-a-chip (B3C) in vitro assay is suitable for the study of BBB function as well as screening of novel therapeutics in real-time. PKCδ activation is a key signaling event that alters the structural and functional integrity of BBB leading to vascular damage and inflammation-induced tissue damage. PKCδ-TAT peptide inhibitor has therapeutic potential for the prevention or reduction of cerebrovascular injury in sepsis-induced vascular damage.
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Affiliation(s)
- Yuan Tang
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, PA, 19122, USA
| | - Fariborz Soroush
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, PA, 19122, USA
| | - Shuang Sun
- Center for Inflammation, Clinical and Translational Lung Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Elisabetta Liverani
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Jordan C Langston
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, PA, 19122, USA
| | - Qingliang Yang
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, PA, 19122, USA
| | - Laurie E Kilpatrick
- Center for Inflammation, Clinical and Translational Lung Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Mohammad F Kiani
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, PA, 19122, USA. .,Department of Radiation Oncology, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA.
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20
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Liverani E, Mondrinos MJ, Sun S, Kunapuli SP, Kilpatrick LE. Role of Protein Kinase C-delta in regulating platelet activation and platelet-leukocyte interaction during sepsis. PLoS One 2018; 13:e0195379. [PMID: 29617417 PMCID: PMC5884571 DOI: 10.1371/journal.pone.0195379] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 03/21/2018] [Indexed: 12/25/2022] Open
Abstract
Sepsis is characterized by an intense systemic inflammatory response activating a cascade of proinflammatory events resulting in leukocyte dysregulation and host tissue damage. The lung is particularly susceptible to systemic inflammation, leading to acute lung injury. Key to inflammation-induced lung damage is the excessive migration of neutrophils across the vascular endothelium. The mechanisms which regulate neutrophil activation and migration in sepsis are not well defined but there is growing evidence that platelets are actively involved and play a key role in microvascular permeability and neutrophil-mediated organ damage. We previously identified PKC-delta (PKCδ) as a critical regulator of the inflammatory response in sepsis and demonstrated PKCδ inhibition was lung protective. However, the role of PKCδ in sepsis-induced platelet activation and platelet-leukocyte interactions is not known. In this study, rats underwent sham surgery or cecal ligation and puncture (CLP) to induce sepsis. Following surgeries, a PKCδ inhibitor (200μg/kg) or vehicle (PBS) was administered intra-tracheally. At 24 hours post-surgeries, lung tissue, BAL fluid, and blood samples were collected. While sepsis caused thrombocytopenia, the remaining circulating platelets were activated as demonstrated by increased p-selectin expression, elevated plasma PF4, and enhanced platelet-leukocyte aggregate formation compared to Sham animals. Platelet activation was associated with increased platelet PKCδ activity. Inhibition of PKCδ attenuated sepsis-induced platelet activation, secretion and aggregate formation. Sepsis-induced thrombocytopenia was also significantly reduced and circulating platelet numbers were similar to sham animals. In the lung, sepsis induced significant influx of platelets and neutrophils and the development of lung injury. Administration of the PKCδ inhibitor decreased platelet and neutrophil influx, and was lung protective. Thus, PKCδ inhibition modulated platelet activity both locally and systemically, decreased neutrophil influx into the lung, and was lung protective. We demonstrate for the first time that PKCδ plays an important role in platelet activation and platelet-neutrophil interaction during sepsis.
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Affiliation(s)
- Elisabetta Liverani
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Center for Inflammation, Translational and Clinical Lung Research, Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail:
| | - Mark J. Mondrinos
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Center for Inflammation, Translational and Clinical Lung Research, Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Shuang Sun
- Center for Inflammation, Translational and Clinical Lung Research, Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Satya P. Kunapuli
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Department of Physiology, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Laurie E. Kilpatrick
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Center for Inflammation, Translational and Clinical Lung Research, Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Department of Physiology, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
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Kostyak JC, Liverani E, Kunapuli SP. PKC-epsilon deficiency alters progenitor cell populations in favor of megakaryopoiesis. PLoS One 2017; 12:e0182867. [PMID: 28783756 PMCID: PMC5544228 DOI: 10.1371/journal.pone.0182867] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 07/25/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND It has long been postulated that Protein Kinase C (PKC) is an important regulator of megakaryopoiesis. Recent contributions to the literature have outlined the functions of several individual PKC isoforms with regard to megakaryocyte differentiation and platelet production. However, the exact role of PKCε remains elusive. OBJECTIVE To delineate the role of PKCε in megakaryopoiesis. APPROACH AND RESULTS We used a PKCε knockout mouse model to examine the effect of PKCε deficiency on platelet mass, megakaryocyte mass, and bone marrow progenitor cell distribution. We also investigated platelet recovery in PKCε null mice and TPO-mediated signaling in PKCε null megakaryocytes. PKCε null mice have higher platelet counts due to increased platelet production compared to WT littermate controls (p<0.05, n = 8). Furthermore, PKCε null mice have more bone marrow megakaryocyte progenitor cells than WT littermate control mice. Additionally, thrombopoietin-mediated signaling is perturbed in PKCε null mice as Akt and ERK1/2 phosphorylation are enhanced in PKCε null megakaryocytes stimulated with thrombopoietin. Finally, in response to immune-induced thrombocytopenia, PKCε null mice recovered faster and had higher rebound thrombocytosis than WT littermate control mice. CONCLUSIONS Enhanced platelet recovery could be due to an increase in megakaryocyte progenitor cells found in PKCε null mice as well as enhanced thrombopoietin-mediated signaling observed in PKCε deficient megakaryocytes. These data suggest that PKCε is a negative regulator of megakaryopoiesis.
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Affiliation(s)
- John C. Kostyak
- Sol Sherry Thrombosis Research Center, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Elisabetta Liverani
- Center for Inflammation, Translational and Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Satya P. Kunapuli
- Sol Sherry Thrombosis Research Center, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Pharmacology, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Physiology, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, United States of America
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Unsworth AJ, Bye AP, Gibbins JM. Platelet-Derived Inhibitors of Platelet Activation. PLATELETS IN THROMBOTIC AND NON-THROMBOTIC DISORDERS 2017. [PMCID: PMC7123044 DOI: 10.1007/978-3-319-47462-5_37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
Platelets are small, anucleate circulating cells that possess a dynamic repertoire of functions spanning the hemostatic, inflammatory, and immune continuum. Once thought to be merely cell fragments with responses limited primarily to acute hemostasis and vascular wall repair, platelets are now increasingly recognized as key sentinels and effector cells regulating host responses to many inflammatory and infectious cues. Platelet granules, including α-granules and dense-granules, store hundreds of factors and secrete these mediators in response to activating signals. The cargo packaged and stored within platelet granules orchestrates communication between platelets and other circulating cells, augments host defense mechanisms to invading pathogens and tumor cells, and - in some settings - drives dysregulated and injurious responses. This focused review will highlight several of the established and emerging mechanisms and roles of platelet secretion in inflammatory and infectious diseases.
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Affiliation(s)
- Bhanu K Manne
- a The University of Utah Molecular Medicine Program , Salt Lake City , Utah , USA
| | | | - Matthew T Rondina
- a The University of Utah Molecular Medicine Program , Salt Lake City , Utah , USA.,c Department of Internal Medicine , Salt Lake City , Utah , USA.,d The GRECC, George E. Wahlen Salt Lake City VAMC , Salt Lake City , Utah , USA
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Tsai JY, Rédei D, Forgo P, Li Y, Vasas A, Hohmann J, Wu CC. Isolation of Phorbol Esters from Euphorbia grandicornis and Evaluation of Protein Kinase C- and Human Platelet-Activating Effects of Euphorbiaceae Diterpenes. JOURNAL OF NATURAL PRODUCTS 2016; 79:2658-2666. [PMID: 27731641 DOI: 10.1021/acs.jnatprod.6b00603] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Human platelets contain conventional (α and β) and novel isoforms of PKC (δ and θ), and PKC activation can result in platelet aggregation and secretion reaction that are important for thrombus formation. Several tumor-promoting Euphorbiaceae diterpenes are known to act as direct activators of PKC, but many types of such diterpenes have not been studied as platelet stimulators. In the present study, two new and five known phorbol esters were isolated from Euphorbia grandicornis. Two of the isolated phorbol esters together with compounds representing ingenane, jatrophane, and myrsinane structural types were studied on PKC activation and platelet stimulation. The investigated phorbol esters and ingenane esters induced blood platelet aggregation and ATP secretion. PKC activation was demonstrated by inducing membrane translocation of PKCs, phosphorylation of PKC substrates, and activation of PKC signaling pathways. The PKC-activating effect of the compounds correlated well with their efficacy to cause platelet stimulation. Moreover, by using an isoform-specific PKC inhibitor, it was found that besides conventional PKCs novel PKCs also play a positive role in platelet activation caused by phorbol/ingenane esters, especially in regulating platelet aggregation. The present results suggest that platelets afford a useful model for studying PKC activators of natural origin or their chemical derivatives.
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Affiliation(s)
- Ju-Ying Tsai
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Dóra Rédei
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Peter Forgo
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Yu Li
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Andrea Vasas
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Judit Hohmann
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Chin-Chung Wu
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
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25
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Distinctive roles of PKC delta isozyme in platelet function. Curr Res Transl Med 2016; 64:135-139. [PMID: 27765273 DOI: 10.1016/j.retram.2016.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 05/15/2016] [Accepted: 05/20/2016] [Indexed: 12/15/2022]
Abstract
Platelet activation is a complex balance of positive and negative signaling pathways. Several protein kinase C (PKC) isoforms are expressed in human platelets. They are a major regulator of platelet granule secretion, activation and aggregation activity. One of those isoforms is the PKCδ isozyme, it has a central yet complex role in platelets such as opposite signaling functions depending on the nature of the agonist, it concentration and pathway. In fact, it has been shown that PKCδ has an overall negative influence on platelet function in response to collagen, while, following PAR stimulation, PKCδ has a positive effect on platelet function. Understanding the crucial role of PKCδ in platelet functions is recently emerging in the literature, therefore, further investigations should shed light into its specific role in hemostasis. In this review, we focus on the different roles of PKCδ in platelet activation, aggregation and thrombus formation.
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Zaid Y, Senhaji N, Naya A, Fadainia C, Kojok K. PKCs in thrombus formation. ACTA ACUST UNITED AC 2015; 63:268-71. [PMID: 26476932 DOI: 10.1016/j.patbio.2015.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 09/01/2015] [Indexed: 10/22/2022]
Abstract
The protein kinase C (PKC) family has been implicated in several physiological processes regulating platelet activation. Each isoform of PKC expressed on platelets, may have a positive and/or negative role depending on the nature and concentration of the agonist. Mice lacking PKCα show much reduced thrombus formation in vivo, while PKCθ(-/-) showed inhibition of aggregation in response to PAR4. On the other hand, PKCδ by associating with Fyn, inhibits platelet aggregation. In addition, PKCβ by interacting with its receptor RACK1 has been implicated in the primary phases of signaling via the αIIbβ3 and finally PKCɛ appears to be involved in platelet function downstream GPVI. The present review discusses the latest observations relevant to the role of individual PKC isoforms in platelet activation and thrombus formation.
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Affiliation(s)
- Y Zaid
- Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, H1T 1C8 Quebec, Canada.
| | - N Senhaji
- Laboratory of Genetic and Molecular Pathology (LGPM), Medical School, Hassan II University, Casablanca, Morocco
| | - A Naya
- Laboratory of Physiology and Molecular Genetic, Faculty of Sciences, Hassan II University, Casablanca, Morocco
| | - C Fadainia
- Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, H1T 1C8 Quebec, Canada
| | - K Kojok
- Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, H1T 1C8 Quebec, Canada
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27
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Bhavanasi D, Badolia R, Manne BK, Janapati S, Dangelmaier CT, Mazharian A, Jin J, Kim S, Zhang X, Chen X, Senis YA, Kunapuli SP. Cross talk between serine/threonine and tyrosine kinases regulates ADP-induced thromboxane generation in platelets. Thromb Haemost 2015; 114:558-68. [PMID: 25947062 DOI: 10.1160/th14-09-0775] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 03/26/2015] [Indexed: 11/05/2022]
Abstract
ADP-induced thromboxane generation depends on Src family kinases (SFKs) and is enhanced with pan-protein kinase C (PKC) inhibitors, but it is not clear how these two events are linked. The aim of the current study is to investigate the role of Y311 phosphorylated PKCδ in regulating ADP-induced platelet activation. In the current study, we employed various inhibitors and murine platelets from mice deficient in specific molecules to evaluate the role of PKCδ in ADP-induced platelet responses. We show that, upon stimulation of platelets with 2MeSADP, Y311 on PKCδ is phosphorylated in a P2Y1/Gq and Lyn-dependent manner. By using PKCδ and Lyn knockout murine platelets, we also show that tyrosine phosphorylated PKCδ plays a functional role in mediating 2MeSADP-induced thromboxane generation. 2MeSADP-induced PKCδ Y311 phosphorylation and thromboxane generation were potentiated in human platelets pre-treated with either a pan-PKC inhibitor, GF109203X or a PKC α/β inhibitor and in PKC α or β knockout murine platelets compared to controls. Furthermore, we show that PKC α/β inhibition potentiates the activity of SFK, which further hyper-phosphorylates PKCδ and potentiates thromboxane generation. These results show for the first time that tyrosine phosphorylated PKCδ regulates ADP-induced thromboxane generation independent of its catalytic activity and that classical PKC isoforms α/β regulate the tyrosine phosphorylation on PKCδ and subsequent thromboxane generation through tyrosine kinase, Lyn, in platelets.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Satya P Kunapuli
- Satya P. Kunapuli PhD, Department of Physiology and Sol Sherry Thrombosis Center,, Temple University School of Medicine,, 3420 North Broad street, MRB 414, Philadelphia PA, 19140, USA, Tel.: +1 215 707 4615, Fax: +1 215 707 6944, E-mail:
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28
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Li J, Kim K, Barazia A, Tseng A, Cho J. Platelet-neutrophil interactions under thromboinflammatory conditions. Cell Mol Life Sci 2015; 72:2627-43. [PMID: 25650236 DOI: 10.1007/s00018-015-1845-y] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Revised: 01/07/2015] [Accepted: 01/26/2015] [Indexed: 12/11/2022]
Abstract
Platelets primarily mediate hemostasis and thrombosis, whereas leukocytes are responsible for immune responses. Since platelets interact with leukocytes at the site of vascular injury, thrombosis and vascular inflammation are closely intertwined and occur consecutively. Recent studies using real-time imaging technology demonstrated that platelet-neutrophil interactions on the activated endothelium are an important determinant of microvascular occlusion during thromboinflammatory disease in which inflammation is coupled to thrombosis. Although the major receptors and counter receptors have been identified, it remains poorly understood how heterotypic platelet-neutrophil interactions are regulated under disease conditions. This review discusses our current understanding of the regulatory mechanisms of platelet-neutrophil interactions in thromboinflammatory disease.
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Affiliation(s)
- Jing Li
- Department of Pharmacology, University of Illinois College of Medicine, 835 S. Wolcott Ave, E403, Chicago, IL, 60612, USA
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29
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Kostyak JC, Bhavanasi D, Liverani E, McKenzie SE, Kunapuli SP. Protein kinase C δ deficiency enhances megakaryopoiesis and recovery from thrombocytopenia. Arterioscler Thromb Vasc Biol 2014; 34:2579-85. [PMID: 25359855 DOI: 10.1161/atvbaha.114.304492] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE We previously determined that protein kinase C δ (PKCδ) regulates platelet function. However, the function of PKCδ in megakaryopoiesis is unknown. APPROACH AND RESULTS Using PKCδ(-/-) and wild-type littermate mice, we found that deficiency of PKCδ caused an increase in white blood cells and platelet counts, as well as in bone marrow and splenic megakaryocytes (P<0.05). Additionally, the megakaryocyte number and DNA content were enhanced in PKCδ(-/-) mouse bone marrow after culturing with exogenous thrombopoietin compared with wild-type (P<0.05). Importantly, thrombopoietin-induced signaling was also altered with PKCδ deletion because both extracellular signal-regulated kinase and Akt308 phosphorylation were heightened in PKCδ(-/-) megakaryocytes compared with wild-type. Finally, PKCδ(-/-) mice recovered faster and had a heightened rebound thrombocytosis after thrombocytopenic challenge. CONCLUSIONS These data suggest that PKCδ is an important megakaryopoietic protein, which regulates signaling induced by thrombopoietin and represents a potential therapeutic target.
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Affiliation(s)
- John C Kostyak
- From the Sol Sherry Thrombosis Research Center (J.C.K., D.B, S.P.K.), Department of Pharmacology and Department of Physiology (S.P.K.), Temple University School of Medicine, Philadelphia, PA; and Cardeza Division of Hematology, Department of Medicine, Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA (S.E.M.)
| | - Dheeraj Bhavanasi
- From the Sol Sherry Thrombosis Research Center (J.C.K., D.B, S.P.K.), Department of Pharmacology and Department of Physiology (S.P.K.), Temple University School of Medicine, Philadelphia, PA; and Cardeza Division of Hematology, Department of Medicine, Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA (S.E.M.)
| | - Elisabeta Liverani
- From the Sol Sherry Thrombosis Research Center (J.C.K., D.B, S.P.K.), Department of Pharmacology and Department of Physiology (S.P.K.), Temple University School of Medicine, Philadelphia, PA; and Cardeza Division of Hematology, Department of Medicine, Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA (S.E.M.)
| | - Steven E McKenzie
- From the Sol Sherry Thrombosis Research Center (J.C.K., D.B, S.P.K.), Department of Pharmacology and Department of Physiology (S.P.K.), Temple University School of Medicine, Philadelphia, PA; and Cardeza Division of Hematology, Department of Medicine, Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA (S.E.M.)
| | - Satya P Kunapuli
- From the Sol Sherry Thrombosis Research Center (J.C.K., D.B, S.P.K.), Department of Pharmacology and Department of Physiology (S.P.K.), Temple University School of Medicine, Philadelphia, PA; and Cardeza Division of Hematology, Department of Medicine, Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA (S.E.M.).
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30
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Bhavanasi D, Kostyak JC, Swindle J, Kilpatrick LE, Kunapuli SP. CGX1037 is a novel PKC isoform delta selective inhibitor in platelets. Platelets 2014; 26:2-9. [PMID: 24433221 DOI: 10.3109/09537104.2013.868877] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Platelets upon activation change their shape, aggregate and secrete alpha and dense granule contents among which ADP acts as a feedback activator. Different Protein Kinase C (PKC) isoforms have specific non-redundant roles in mediating platelet responses including secretion and thrombus formation. Murine platelets lacking specific PKC isoforms have been used to evaluate the isoform specific functions. Novel PKC isoform δ has been shown to play an important role in some pathological processes. Lack of specific inhibitors for PKCδ has restricted analysis of its role in various cells. The current study was carried out to evaluate a novel small molecule PKCδ inhibitor, CGX1037 in platelets. Platelet aggregation, dense granule secretion and western blotting experiments were performed to evaluate CGX1037. In human platelets, CGX1037 inhibited PAR4-mediated phosphorylation on PKD2, a PKCδ-specific substrate. Pre-treatment of human or murine platelets with CGX1037 inhibited PAR4-mediated dense granule secretion whereas it potentiated GPVI-mediated dense granule secretion similar to the responses observed in murine platelets lacking PKCδ· Furthermore, pre-treatment of platelets from PKCδ(-/-) mice with CGX1037 had no significant additive effect on platelet responses suggesting the specificity of CGX1037. Hence, we show that CGX1037 is a selective small molecule inhibitor of PKCδ in platelets.
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Affiliation(s)
- Dheeraj Bhavanasi
- Department of Physiology, Temple University School of Medicine , Philadelphia, PA , USA
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31
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Zimman A, Titz B, Komisopoulou E, Biswas S, Graeber TG, Podrez EA. Phosphoproteomic analysis of platelets activated by pro-thrombotic oxidized phospholipids and thrombin. PLoS One 2014; 9:e84488. [PMID: 24400094 PMCID: PMC3882224 DOI: 10.1371/journal.pone.0084488] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 11/15/2013] [Indexed: 11/19/2022] Open
Abstract
Specific oxidized phospholipids (oxPCCD36) promote platelet hyper-reactivity and thrombosis in hyperlipidemia via the scavenger receptor CD36, however the signaling pathway(s) induced in platelets by oxPCCD36 are not well defined. We have employed mass spectrometry-based tyrosine, serine, and threonine phosphoproteomics for the unbiased analysis of platelet signaling pathways induced by oxPCCD36 as well as by the strong physiological agonist thrombin. oxPCCD36 and thrombin induced differential phosphorylation of 115 proteins (162 phosphorylation sites) and 181 proteins (334 phosphorylation sites) respectively. Most of the phosphoproteome changes induced by either agonist have never been reported in platelets; thus they provide candidates in the study of platelet signaling. Bioinformatic analyses of protein phosphorylation dependent responses were used to categorize preferential motifs for (de)phosphorylation, predict pathways and kinase activity, and construct a phosphoproteome network regulating integrin activation. A putative signaling pathway involving Src-family kinases, SYK, and PLCγ2 was identified in platelets activated by oxPCCD36. Subsequent ex vivo studies in human platelets demonstrated that this pathway is downstream of the scavenger receptor CD36 and is critical for platelet activation by oxPCCD36. Our results provide multiple insights into the mechanism of platelet activation and specifically in platelet regulation by oxPCCD36.
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Affiliation(s)
- Alejandro Zimman
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Bjoern Titz
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, Institute for Molecular Medicine, Jonsson Comprehensive Cancer Center and California NanoSystems Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Evangelia Komisopoulou
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, Institute for Molecular Medicine, Jonsson Comprehensive Cancer Center and California NanoSystems Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Sudipta Biswas
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Thomas G. Graeber
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, Institute for Molecular Medicine, Jonsson Comprehensive Cancer Center and California NanoSystems Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Eugene A. Podrez
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- * E-mail:
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32
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Golebiewska EM, Poole AW. Secrets of platelet exocytosis - what do we really know about platelet secretion mechanisms? Br J Haematol 2013; 165:204-216. [PMID: 24588354 PMCID: PMC4155865 DOI: 10.1111/bjh.12682] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Upon activation by extracellular matrix components or soluble agonists, platelets release in excess of 300 active molecules from intracellular granules. Those factors can both activate further platelets and mediate a range of responses in other cells. The complex microenvironment of a growing thrombus, as well as platelets' roles in both physiological and pathological processes, require platelet secretion to be highly spatially and temporally regulated to ensure appropriate responses to a range of stimuli. However, how this regulation is achieved remains incompletely understood. In this review we outline the importance of regulated secretion in thrombosis as well as in 'novel' scenarios beyond haemostasis and give a detailed summary of what is known about the molecular mechanisms of platelet exocytosis. We also discuss a number of theories of how different cargoes could be released in a tightly orchestrated manner, allowing complex interactions between platelets and their environment.
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Affiliation(s)
- Ewelina M Golebiewska
- School of Physiology and Pharmacology, Bristol Heart Institute, University of Bristol, Bristol, UK
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33
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Buitrago L, Bhavanasi D, Dangelmaier C, Manne BK, Badolia R, Borgognone A, Tsygankov AY, McKenzie SE, Kunapuli SP. Tyrosine phosphorylation on spleen tyrosine kinase (Syk) is differentially regulated in human and murine platelets by protein kinase C isoforms. J Biol Chem 2013; 288:29160-9. [PMID: 23960082 DOI: 10.1074/jbc.m113.464107] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Protein kinase C (PKC) isoforms differentially regulate platelet functional responses downstream of glycoprotein VI (GPVI) signaling, but the role of PKCs regulating upstream effectors such as Syk is not known. We investigated the role of PKC on Syk tyrosine phosphorylation using the pan-PKC inhibitor GF109203X (GFX). GPVI-mediated phosphorylation on Syk Tyr-323, Tyr-352, and Tyr-525/526 was rapidly dephosphorylated, but GFX treatment inhibited this dephosphorylation on Tyr-525/526 in human platelets but not in wild type murine platelets. GFX treatment did not affect tyrosine phosphorylation on FcRγ chain or Src family kinases. Phosphorylation of Lat Tyr-191 and PLCγ2 Tyr-759 was also increased upon treatment with GFX. We evaluated whether secreted ADP is required for such dephosphorylation. Exogenous addition of ADP to GFX-treated platelets did not affect tyrosine phosphorylation on Syk. FcγRIIA- or CLEC-2-mediated Syk tyrosine phosphorylation was also potentiated with GFX in human platelets. Because potentiation of Syk phosphorylation is not observed in murine platelets, PKC-deficient mice cannot be used to identify the PKC isoform regulating Syk phosphorylation. We therefore used selective inhibitors of PKC isoforms. Only PKCβ inhibition resulted in Syk hyperphosphorylation similar to that in platelets treated with GFX. This result indicates that PKCβ is the isoform responsible for Syk negative regulation in human platelets. In conclusion, we have elucidated a novel pathway of Syk regulation by PKCβ in human platelets.
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Dovizio M, Maier TJ, Alberti S, Di Francesco L, Marcantoni E, Münch G, John CM, Suess B, Sgambato A, Steinhilber D, Patrignani P. Pharmacological inhibition of platelet-tumor cell cross-talk prevents platelet-induced overexpression of cyclooxygenase-2 in HT29 human colon carcinoma cells. Mol Pharmacol 2013; 84:25-40. [PMID: 23580446 PMCID: PMC11037430 DOI: 10.1124/mol.113.084988] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 04/11/2013] [Indexed: 04/26/2024] Open
Abstract
Cyclooxygenase (COX)-2-derived prostanoids can influence several processes that are linked to carcinogenesis. We aimed to address the hypothesis that platelets contribute to aberrant COX-2 expression in HT29 colon carcinoma cells and to reveal the role of platelet-induced COX-2 on the expression of proteins involved in malignancy and marker genes of epithelial-mesenchymal transition (EMT). Human platelets cocultured with HT29 cells rapidly adhered to cancer cells and induced COX-2 mRNA expression, but not protein synthesis, which required the late release of platelet-derived growth factor and COX-2 mRNA stabilization. Platelet-induced COX-2-dependent prostaglandin E2 (PGE2) synthesis in HT29 cells was involved in the downregulation of p21(WAF1/CIP1) and the upregulation of cyclinB1 since these effects were prevented by rofecoxib (a selective COX-2 inhibitor) and rescued by exogenous PGE2. Galectin-3, which is highly expressed in HT29 cells, is unique among galectins because it contains a collagen-like domain. Thus, we studied the role of galectin-3 and platelet collagen receptors in platelet-induced COX-2 overexpression. Inhibitors of galectin-3 function (β-lactose, a dominant-negative form of galectin-3, Gal-3C, and anti-galectin-3 antibody M3/38) or collagen receptor-mediated platelet adhesion (revacept, a dimeric platelet collagen receptor GPVI-Fc) prevented aberrant COX-2 expression. Inhibition of platelet-cancer cell interaction by revacept was more effective than rofecoxib in preventing platelet-induced mRNA changes of EMT markers, suggesting that direct cell-cell contact and aberrant COX-2 expression synergistically induced gene expression modifications associated with EMT. In conclusion, our findings provide the rationale for testing blockers of collagen binding sites, such as revacept, and galectin-3 inhibitors in the prevention of colon cancer metastasis in animal models, followed by studies in patients.
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Affiliation(s)
- Melania Dovizio
- Department of Neuroscience and Imaging and Center of Excellence on Aging (CeSI), G. d'Annunzio University, Via dei Vestini, 31, 66100 Chieti, Italy
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Moncada de la Rosa C, Radziwon-Balicka A, El-Sikhry H, Seubert J, Ruvolo PP, Radomski MW, Jurasz P. Pharmacologic Protein Kinase CαInhibition Uncouples Human Platelet-Stimulated Angiogenesis from Collagen-Induced Aggregation. J Pharmacol Exp Ther 2013; 345:15-24. [DOI: 10.1124/jpet.112.200881] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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Xiang B, Zhang G, Stefanini L, Bergmeier W, Gartner TK, Whiteheart SW, Li Z. The Src family kinases and protein kinase C synergize to mediate Gq-dependent platelet activation. J Biol Chem 2012; 287:41277-87. [PMID: 23066026 DOI: 10.1074/jbc.m112.393124] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Src family kinases (SFKs) play essential roles in collagen- and von Willebrand factor (VWF)-mediated platelet activation. However, the roles of SFKs in G protein-coupled receptor-mediated platelet activation and the molecular mechanisms whereby SFKs are activated by G protein-coupled receptor stimulation are not fully understood. Here we show that the thrombin receptor protease-activated receptor 4 agonist peptide AYPGKF elicited SFK phosphorylation in P2Y(12) deficient platelets but stimulated minimal SFK phosphorylation in platelets lacking G(q). We have previously shown that thrombin-induced SFK phosphorylation was inhibited by the calcium chelator 5,5'-dimethyl-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (dimethyl-BAPTA). The calcium ionophore A23187 induced SFK phosphorylation in both wild-type and G(q) deficient platelets. Together, these results indicate that SFK phosphorylation in response to thrombin receptor stimulation is downstream from G(q)/Ca(2+) signaling. Moreover, A23187-induced thromboxane A(2) synthesis, platelet aggregation, and secretion were inhibited by preincubation of platelets with a selective SFK inhibitor, PP2. AYPGKF-induced thromboxane A(2) production in wild-type and P2Y(12) deficient platelets was abolished by PP2, and AYPGKF-mediated P-selectin expression, integrin α(IIb)β(3) activation, and aggregation of P2Y(12) deficient platelets were partially inhibited by the PKC inhibitor Ro-31-8220, PP2, dimethyl-BAPTA, or LY294002, but were abolished by Ro-31-8220 plus PP2, dimethyl-BAPTA, or LY294002. These data indicate that Ca(2+)/SFKs/PI3K and PKC represent two alternative signaling pathways mediating G(q)-dependent platelet activation.
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Affiliation(s)
- Binggang Xiang
- Saha Cardiovascular Research Center, College of Medicine, University of Kentucky, Lexington, Kentucky 40536, USA
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UNSWORTH AJ, FINNEY BA, NAVARRO-NUNEZ L, SEVERIN S, WATSON SP, PEARS CJ. Protein kinase Cε and protein kinase Cθ double-deficient mice have a bleeding diathesis. J Thromb Haemost 2012; 10:1887-94. [PMID: 22812584 PMCID: PMC3532618 DOI: 10.1111/j.1538-7836.2012.04857.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 07/10/2012] [Indexed: 01/24/2023]
Abstract
BACKGROUND In comparison to the classical isoforms of protein kinase C (PKC), the novel isoforms are thought to play minor or inhibitory roles in the regulation of platelet activation and thrombosis. OBJECTIVES To measure the levels of PKCθ and PKCε and to investigate the phenotype of mice deficient in both novel PKC isoforms. METHODS Tail bleeding and platelet activation assays were monitored in mice and platelets from mice deficient in both PKCθ and PKCε. RESULTS PKCε plays a minor role in supporting aggregation and secretion following stimulation of the collagen receptor GPVI in mouse platelets but has no apparent role in spreading on fibrinogen. PKCθ, in contrast, plays a minor role in supporting adhesion and filopodial generation on fibrinogen but has no apparent role in aggregation and secretion induced by GPVI despite being expressed at over 10 times the level of PKCε. Platelets deficient in both novel isoforms have a similar pattern of aggregation downstream of GPVI and spreading on fibrinogen as the single null mutants. Strikingly, a marked reduction in aggregation on collagen under arteriolar shear conditions is observed in blood from the double but not single-deficient mice along with a significant increase in tail bleeding. CONCLUSIONS These results reveal a greater than additive role for PKCθ and PKCε in supporting platelet activation under shear conditions and demonstrate that, in combination, the two novel PKCs support platelet activation.
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Affiliation(s)
- A J UNSWORTH
- Department of Biochemistry, University of OxfordOxford
| | - B A FINNEY
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of BirminghamBirmingham, UK
| | - L NAVARRO-NUNEZ
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of BirminghamBirmingham, UK
| | - S SEVERIN
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of BirminghamBirmingham, UK
| | - S P WATSON
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of BirminghamBirmingham, UK
| | - C J PEARS
- Department of Biochemistry, University of OxfordOxford
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Bynagari-Settipalli YS, Lakhani P, Jin J, Bhavaraju K, Rico MC, Kim S, Woulfe D, Kunapuli SP. Protein kinase C isoform ε negatively regulates ADP-induced calcium mobilization and thromboxane generation in platelets. Arterioscler Thromb Vasc Biol 2012; 32:1211-9. [PMID: 22362759 DOI: 10.1161/atvbaha.111.242388] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Members of the protein kinase C (PKC) family are shown to positively and negatively regulate platelet activation. Although positive regulatory roles are extensively studied, negative regulatory roles of PKCs are poorly understood. We investigated the mechanism and specific isoforms involved in PKC-mediated negative regulation of ADP-induced functional responses. METHODS AND RESULTS A pan-PKC inhibitor, GF109203X, potentiated ADP-induced cPLA(2) phosphorylation and thromboxane generation as well as ERK activation and intracellular calcium (Ca(2+)(i)) mobilization, 2 signaling molecules, upstream of cPLA(2) activation. Thus, PKCs inhibit cPLA(2) activation by inhibiting ERK and Ca(2+)(i) mobilization. Because the inhibitor of classic PKC isoforms, GO-6976, did not affect ADP-mediated thromboxane generation, we investigated the role of novel class of PKC isoforms. ADP-induced thromboxane generation, calcium mobilization, and ERK phosphorylation were potentiated in PKCε null murine platelets compared with platelets from wild-type littermates. Interestingly, when thromboxane release is blocked, ADP-induced aggregation in PKCε knockout and wild-type was similar, suggesting that PKCε does not affect ADP-induced aggregation directly. PKCε knockout mice exhibited shorter times to occlusion in an FeCl(3)-induced arterial injury model and shorter bleeding times in tail-bleeding experiments. CONCLUSIONS We conclude that PKCε negatively regulates ADP-induced thromboxane generation in platelets and offers protection against thrombosis.
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Abstract
Three classes of inhibitors of platelet aggregation have demonstrated substantial clinical benfits. Aspirin acts by irreversibly inhibiting COX-1 and therefore blocking the synthesis of proaggregatory thromboxane A (2) (TxA(2)). The indirect acting (ticlopidine, clopidogrel, prasugrel) and the direct acting (ticagrelor) antagonists of P2Y(12) block the thrombus stabilizing activity of ADP. Parenteral GP IIb-IIIa inhibitors directly block platelet-platelet interactions. Despite well-established benefits, all antiplatelet agents have important limitations: increased bleeding and gastrointestinal toxicities (aspirin), high incidence of thrombotic thrombocytopenic purpura (ticlopidine), potentially nonresponders (clopidogrel), severe bleeding (prasugrel, GP IIb-IIIa antagonists) and "complicated" relationships with aspirin ticagrelor). In this chapter, we present the genetic and pharmacological evidence that supports the development and expectations associated with novel antiplatelet strategies directed at intrasignaling pathways.
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Affiliation(s)
- Patrick Andre
- Portola Pharmaceuticals Inc, 270 E. Grand Avenue, Suite 22 South, San Francisco, CA 94080, USA.
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Yeung J, Apopa PL, Vesci J, Kenyon V, Rai G, Jadhav A, Simeonov A, Holman TR, Maloney DJ, Boutaud O, Holinstat M. Protein kinase C regulation of 12-lipoxygenase-mediated human platelet activation. Mol Pharmacol 2011; 81:420-30. [PMID: 22155783 DOI: 10.1124/mol.111.075630] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Platelet activation is important in the regulation of hemostasis and thrombosis. Uncontrolled activation of platelets may lead to arterial thrombosis, which is a major cause of myocardial infarction and stroke. After activation, metabolism of arachidonic acid (AA) by 12-lipoxygenase (12-LOX) may play a significant role in regulating the degree and stability of platelet activation because inhibition of 12-LOX significantly attenuates platelet aggregation in response to various agonists. Protein kinase C (PKC) activation is also known to be an important regulator of platelet activity. Using a newly developed selective inhibitor for 12-LOX and a pan-PKC inhibitor, we investigated the role of PKC in 12-LOX-mediated regulation of agonist signaling in the platelet. To determine the role of PKC within the 12-LOX pathway, a number of biochemical endpoints were measured, including platelet aggregation, calcium mobilization, and integrin activation. Inhibition of 12-LOX or PKC resulted in inhibition of dense granule secretion and attenuation of both aggregation and αIIbβ(3) activation. However, activation of PKC downstream of 12-LOX inhibition rescued agonist-induced aggregation and integrin activation. Furthermore, inhibition of 12-LOX had no effect on PKC-mediated aggregation, indicating that 12-LOX is upstream of PKC. These studies support an essential role for PKC downstream of 12-LOX activation in human platelets and suggest 12-LOX as a possible target for antiplatelet therapy.
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Affiliation(s)
- Jennifer Yeung
- Department of Medicine, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Williams CM, Feng Y, Martin P, Poole AW. Protein kinase C alpha and beta are positive regulators of thrombus formation in vivo in a zebrafish (Danio rerio) model of thrombosis. J Thromb Haemost 2011; 9:2457-65. [PMID: 21951302 DOI: 10.1111/j.1538-7836.2011.04520.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND The zebrafish (Danio rerio) is becoming an attractive model organism for the assessment of gene function in thrombosis in vivo. Zebrafish, as a thrombosis model, have several advantages, with the capacity to follow thrombus formation at high resolution in real time using intravital microscopy, without the need for complex surgical techniques, and the capability to rapidly knockdown gene expression using morpholino antisense approaches. OBJECTIVES We have recently shown, in mouse models, that protein kinase C alpha (PKCα) plays a critical role in regulating thrombus formation in vivo. PKC beta (β) plays a non-redundant role also in platelet function in vitro, but the function of this gene had not yet been assessed in vivo. METHODS In the present study, we analyzed the function of both PKCα and PKCβ in the zebrafish model in vivo, by live imaging using a laser-induced injury of the main caudal artery in 3-day-old larvae. RESULTS We showed that D. rerio express orthologs of both the PKCα and PKCβ genes, with high sequence identity. Translation blocking and splice-blocking morpholinos effectively and specifically knockdown expression of these genes and knockdown with either morpholino leads to attenuated thrombus formation, as assessed by several quantitative parameters including time to initial adhesion and peak thrombus surface area. CONCLUSIONS Our data indicate that these two highly related genes play non-redundant roles in regulating thrombosis, an observation that supports our previous in vitro murine data, and suggests unique roles, and possibly unique regulation, for PKCα and PKCβ in controlling platelet function in vivo.
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Affiliation(s)
- C M Williams
- School of Physiology & Pharmacology, University Walk, Bristol, UK
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Bhavanasi D, Kim S, Goldfinger LE, Kunapuli SP. Protein kinase Cδ mediates the activation of protein kinase D2 in platelets. Biochem Pharmacol 2011; 82:720-7. [PMID: 21736870 DOI: 10.1016/j.bcp.2011.06.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 06/17/2011] [Accepted: 06/20/2011] [Indexed: 01/25/2023]
Abstract
Protein kinase D (PKD) is a subfamily of serine/threonine specific family of kinases, comprised of PKD1, PKD2 and PKD3 (PKCμ, PKD2 and PKCv in humans). It is known that PKCs activate PKD, but the relative expression of isoforms of PKD or the specific PKC isoform/s responsible for its activation in platelets is not known. This study is aimed at investigating the pathway involved in activation of PKD in platelets. We show that PKD2 is the major isoform of PKD that is expressed in human as well as murine platelets but not PKD1 or PKD3. PKD2 activation induced by AYPGKF was abolished with a G(q) inhibitor YM-254890, but was not affected by Y-27632, a RhoA/p160ROCK inhibitor, indicating that PKD2 activation is G(q)-, but not G₁₂/₁₃-mediated Rho-kinase dependent. Calcium-mediated signals are also required for activation of PKD2 as dimethyl BAPTA inhibited its phosphorylation. GF109203X, a pan PKC inhibitor abolished PKD2 phosphorylation but Go6976, a classical PKC inhibitor had no effect suggesting that novel PKC isoforms are involved in PKD2 activation. Importantly, Rottlerin, a non-selective PKCδ inhibitor, inhibited AYPGKF-induced PKD2 activation in human platelets. Similarly, AYPGKF- and Convulxin-induced PKD2 phosphorylation was dramatically inhibited in PKCδ-deficient platelets, but not in PKCθ- or PKCɛ-deficient murine platelets compared to that of wild type platelets. Hence, we conclude that PKD2 is a common signaling target downstream of various agonist receptors in platelets and G(q)-mediated signals along with calcium and novel PKC isoforms, in particular, PKCδ activate PKD2 in platelets.
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Affiliation(s)
- Dheeraj Bhavanasi
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA, USA
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Bird JE, Smith PL, Bostwick JS, Shipkova P, Schumacher WA. Bleeding response induced by anti-thrombotic doses of a phosphoinositide 3-kinase (PI3K)-β inhibitor in mice. Thromb Res 2011; 127:560-4. [DOI: 10.1016/j.thromres.2011.02.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Revised: 02/03/2011] [Accepted: 02/10/2011] [Indexed: 02/05/2023]
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Aktan Í, Dunkel B, Cunningham F. PKC isoenzymes in equine platelets and stimulus induced activation. Vet Immunol Immunopathol 2011; 141:276-82. [DOI: 10.1016/j.vetimm.2011.03.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 03/14/2011] [Accepted: 03/21/2011] [Indexed: 12/13/2022]
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Heemskerk JW, Harper MT, Cosemans JM, Poole AW. Unravelling the different functions of protein kinase C isoforms in platelets. FEBS Lett 2011; 585:1711-6. [DOI: 10.1016/j.febslet.2011.05.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 04/28/2011] [Accepted: 05/04/2011] [Indexed: 11/17/2022]
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47
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Lee CH. Treatment of blood flow abnormality using mucosal delivery of nitric oxide. Drug Deliv Transl Res 2011; 1:201-8. [DOI: 10.1007/s13346-011-0026-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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48
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Protein kinase C mediates platelet secretion and thrombus formation through protein kinase D2. Blood 2011; 118:416-24. [PMID: 21527521 DOI: 10.1182/blood-2010-10-312199] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Platelets are highly specialized blood cells critically involved in hemostasis and thrombosis. Members of the protein kinase C (PKC) family have established roles in regulating platelet function and thrombosis, but the molecular mechanisms are not clearly understood. In particular, the conventional PKC isoform, PKCα, is a major regulator of platelet granule secretion, but the molecular pathway from PKCα to secretion is not defined. Protein kinase D (PKD) is a family of 3 kinases activated by PKC, which may represent a step in the PKC signaling pathway to secretion. In the present study, we show that PKD2 is the sole PKD member regulated downstream of PKC in platelets, and that the conventional, but not novel, PKC isoforms provide the upstream signal. Platelets from a gene knock-in mouse in which 2 key phosphorylation sites in PKD2 have been mutated (Ser707Ala/Ser711Ala) show a significant reduction in agonist-induced dense granule secretion, but not in α-granule secretion. This deficiency in dense granule release was responsible for a reduced platelet aggregation and a marked reduction in thrombus formation. Our results show that in the molecular pathway to secretion, PKD2 is a key component of the PKC-mediated pathway to platelet activation and thrombus formation through its selective regulation of dense granule secretion.
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Unsworth AJ, Smith H, Gissen P, Watson SP, Pears CJ. Submaximal inhibition of protein kinase C restores ADP-induced dense granule secretion in platelets in the presence of Ca2+. J Biol Chem 2011; 286:21073-82. [PMID: 21489985 PMCID: PMC3122168 DOI: 10.1074/jbc.m110.187138] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Protein kinase C (PKC) is a family of serine/threonine kinases that play isoform-specific inhibitory and stimulatory roles in platelet activation. We show here that the pan-PKC inhibitor Ro31-8220 can be used to dissect these events following platelet activation by ADP. Submaximal concentrations of Ro31-8220 potentiated aggregation and dense granule secretion to ADP in plasma anticoagulated with citrate, in d-Phe-Pro-Arg-chloromethyl ketone-anticoagulated plasma, which has physiological levels of Ca2+, and in washed platelets. Potentiation was retained on inhibition of cyclooxygenase and was associated with an increase in intracellular Ca2+. Potentiation of aggregation and secretion was abolished by a maximally effective concentration of Ro31-8220, consistent with a critical role of PKC in secretion. ADP-induced secretion was potentiated in the presence of an inhibitor of PKCβ but not in the presence of available inhibitors of other PKC isoforms in human and mouse platelets. ADP-induced secretion was also potentiated in mouse platelets deficient in PKCϵ but not PKCθ. These results demonstrate that partial blockade of PKC potentiates aggregation and dense granule secretion by ADP in association with increased Ca2+. This provides a molecular explanation for the inability of ADP to induce secretion in plasma in the presence of physiological Ca2+ concentrations, and it reveals a novel role for PKC in inhibiting platelet activation by ADP in vivo. These results also demonstrate isoform-specific inhibitory effects of PKC in platelets.
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Affiliation(s)
- Amanda J Unsworth
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
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Getz TM, Mayanglambam A, Daniel JL, Kunapuli SP. Go6976 abrogates GPVI-mediated platelet functional responses in human platelets through inhibition of Syk. J Thromb Haemost 2011; 9:608-10. [PMID: 21251194 PMCID: PMC3057064 DOI: 10.1111/j.1538-7836.2011.04192.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Todd M. Getz
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA, U.S.A
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A
| | - Azad Mayanglambam
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA, U.S.A
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A
| | - James L. Daniel
- Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA, U.S.A
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A
| | - Satya P. Kunapuli
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA, U.S.A
- Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA, U.S.A
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A
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