scholarly journals Human solCD39 inhibits injury-induced development of neointimal hyperplasia

2010 ◽  
Vol 103 (02) ◽  
pp. 426-435 ◽  
Author(s):  
Rosemary Kraemer ◽  
Hao Shen ◽  
Rita Upmacis ◽  
Aaron Marcus ◽  
Elgilda Musi ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Platelet Activation ◽  
Blood Platelets ◽  
Neointimal Hyperplasia ◽  
Endothelial Injury ◽  
Vascular Endothelial ◽  
Leukocyte Infiltration ◽  
Post Injury ◽  
Arterial Lumen ◽  
Activated Platelets

SummaryBlood platelets provide the initial response to vascular endothelial injury, becoming activated as they adhere to the injured site. Activated platelets recruit leukocytes, and initiate proliferation and migration of vascular smooth muscle cells (SMC) within the injured vessel wall, leading to development of neointimal hyperplasia. Endothelial CD39/NTPDase1 and recombinant solCD39 rapidly metabolise nucleotides, including stimulatory ADP released from activated platelets, thereby suppressing additional platelet reactivity. Using a murine model of vascular endothelial injury, we investigated whether circulating human solCD39 could reduce platelet activation and accumulation, thus abating leukocyte infiltration and neointimal formation following vascular damage. Intraperitoneally-administered solCD39 ADP -ase activity in plasma peaked 1 hour (h) post-injection, with an elimination half-life of 43 h. Accordingly, mice were administered solCD39 or saline 1 h prior to vessel injury, then either sacrificed 24 h post-injury or treated with solCD39 or saline (three times weekly) for an additional 18 days. Twenty-four hours post-injury, solCD39-treated mice displayed a reduction in platelet activation and recruitment, P-selectin expression, and leukocyte accumulation in the arterial lumen. Furthermore, repeated administration of solCD39 modulated the late stage of vascular injury by suppressing leukocyte deposition, macrophage infiltration and smooth muscle cell (SMC) proliferation/migration, resulting in abrogation of neointimal thickening. In contrast, injured femoral arteries of saline-injected mice exhibited massive platelet thrombus formation, marked P-selectin expression, and leukocyte infiltration. Pronounced neointimal growth with macrophage and SMC accretion was also observed (intimal-to-medial area ratio 1.56 ± 0.34 at 19 days). Thus, systemic administration of solCD39 profoundly affects injury-induced cellular responses, minimising platelet deposition and leukocyte recruitment, and suppressing neointimal hyperplasia.

scholarly journals A neutralizing IL-11 antibody reduces vessel hyperplasia in a mouse carotid artery wire injury model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
David Schumacher ◽  
Elisa A. Liehn ◽  
Pakhwan Nilcham ◽  
David Castaño Mayan ◽  
Chutima Rattanasopa ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Wall Thickness ◽  
Vessel Wall ◽  
Neointimal Hyperplasia ◽  
Endothelial Injury ◽  
Collagen Content ◽  
Arterial Stenosis ◽  
Matrix Metalloproteinase 2 ◽  
Vessel Wall Thickness ◽  
Artery Disease

AbstractVascular restenosis remains a major problem in patients with coronary artery disease (CAD) and peripheral artery disease (PAD). Neointimal hyperplasia, defined by post-procedure proliferation and migration of vascular smooth muscle cells (VSMCs) is a key underlying pathology. Here we investigated the role of Interleukin 11 (IL-11) in a mouse model of injury-related plaque development. Apoe−/− mice were fed a hyperlipidaemic diet and subjected to carotid wire injury of the right carotid. Mice were injected with an anti-IL11 antibody (X203), IgG control antibody or buffer. We performed ultrasound analysis to assess vessel wall thickness and blood velocity. Using histology and immunofluorescence approaches, we determined the effects of IL-11 inhibition on VSMC and macrophages phenotypes and fibrosis. Treatment of mice with carotid wire injury using X203 significantly reduced post-endothelial injury vessel wall thickness, and injury-related plaque, when compared to control. Immunofluorescence staining of the injury-related plaque showed that X203 treatment did not reduce macrophage numbers, but reduced the number of VSMCs and lowered matrix metalloproteinase 2 (MMP2) levels and collagen content in comparison to control. X203 treatment was associated with a significant increase in smooth muscle protein 22α (SM22α) positive cells in injury-related plaque compared to control, suggesting preservation of the contractile VSMC phenotype. Interestingly, X203 also reduced the collagen content of uninjured carotid arteries as compared to IgG, showing an additional effect on hyperlipidemia-induced arterial remodeling in the absence of mechanical injury. Therapeutic inhibition of IL-11 reduced vessel wall thickness, attenuated neointimal hyperplasia, and has favorable effects on vascular remodeling following wire-induced endothelial injury. This suggests IL-11 inhibition as a potential novel therapeutic approach to reduce arterial stenosis following revascularization in CAD and PAD patients.

The Role of Endothelial Cell Injury and Platelet Response in Atherogenesis

1977 ◽  
Author(s):  
L. A. Harker ◽  
R. Ross ◽  
J. Glomset
Keyword(s):  
Smooth Muscle ◽  
Endothelial Cell ◽  
Connective Tissue ◽  
Smooth Muscle Cells ◽  
Lipid Accumulation ◽  
Blood Platelets ◽  
Muscle Cells ◽  
Endothelial Injury ◽  
Intimal Proliferation ◽  
Flowing Blood

Endothelium forms a resistant barrier between flowing blood and vessel wall structures. Endothelial thromboresistance is maintained in part by the synthesis of prostacyclin, a potent prostaglandin inhibitor of platelet function. Loss of endothelial cells, mediated by physical, chemical, infectious or immune mechanisms, exposes the sub endothelium to flowing blood. Platelets react to the subendothelial connective tissue structures, undergoing adhesion and release of intracellular constituents, including a factor that is mitogenic to smooth muscle cells. This growth factor is a heat stable, basic protein (IP 7.4–9.4) of 20,000 Daltons and appears to be responsible for the intimal proliferation of smooth muscle cells that follows endothelial cell desquamation. After a single injury event the intimal lesion regresses over several months. Repeated or continuous endothelial cell loss results in progressive intimal proliferation of smooth muscle cells, their secretion of connective tissue matrix components (collagen, elastin and proteoglycans) and accumulation of lipid when animals are on a hypercholesterolemic diet to form early atherosclerotic intimal lesions. Discontinuance of endothelial injury and restoration of the endothelium appear to be followed by lesion regression except when lipid accumulation is extensive. Possible approaches to atherosclerosis prevention include: 1) protection of the endothelium by interruption or avoidance of endothelial injury factors, and perhaps by pharmacologic protection; 2) inhibition of platelet reactivity; 3) modification of SMC proliferation, secretion or lipid accumulation.

scholarly journals Calpain I remains intact and intracellular during platelet activation. Immunochemical measurements with monoclonal and polyclonal antibodies

1987 ◽  
Vol 246 (2) ◽  
pp. 481-488 ◽  
Author(s):  
J A Samis ◽  
G Zboril ◽  
J S Elce
Keyword(s):  
Platelet Activation ◽  
Polyclonal Antibodies ◽  
Blood Platelets ◽  
Large Subunit ◽  
Active Form ◽  
Cytoskeletal Proteins ◽  
Exterior Surface ◽  
Activated Platelets ◽  
Igg1 Monoclonal Antibody ◽  
Calpain Ii

As a step towards understanding the physiological function of calpain (Ca2+-activated neutral proteinase, EC 3.4.22.17) in blood platelets, and in view of some suggestions that calpain is transferred to the platelet external surface during platelet activation, the enzyme was studied with immunochemical methods in resting and thrombin-activated cells. (1) A mouse IgG1 monoclonal antibody was prepared which binds strongly only to the denatured large subunit of human calpain I, and weakly to that of human calpain II. A polyclonal antibody raised against rat calpain II was available which, apart from binding strongly to rat calpain II, binds to the large subunits of human calpain I and II about equally. (2) With these antibodies, it was found that calpain could be detected in fixed platelets in suspension only after permeabilization with 0.1% saponin, and could not be detected on the exterior surface of resting or of activated platelets, or in the supernatant media of these platelets. It was concluded that calpain is not significantly externalized during platelet activation. (3) Immunoblotting showed that conversion of the larger calpain I subunit from 80 kDa into 76-78 kDa occurred only when thrombin-activated platelets were stirred to permit aggregation, and did not occur during unstirred thrombin activation. Although an action of calpain in the 80 kDa form on possible platelet substrates such as cytoskeletal proteins cannot be excluded, calpain is certainly not present as the 76-78 kDa form, which is assumed to be its active form, until aggregation is initiated.

scholarly journals Preparations from Selected Cucurbit Vegetables as Antiplatelet Agents – An in Vitro Study

2021 ◽  
Author(s):  
Agata Rolnik ◽  
Bartosz Skalski ◽  
Anna Stochmal ◽  
Beata Olas
Keyword(s):  
Platelet Activation ◽  
Cucurbita Pepo ◽  
Thrombus Formation ◽  
Blood Platelets ◽  
In Vitro Study ◽  
Blood Platelet ◽  
Arachidonic Acid Metabolism ◽  
Platelet Activity ◽  
Activated Platelets

Abstract Increased blood platelet activation plays an important role in cardiovascular diseases (CVDs). Recent experiments indicate that certain fruits and vegetables, including onion, garlic, and beetroot, have anti-platelet potential and therefore may reduce the likelihood of CVDs. While vegetables from the Cucuritaceae family are known to exerting beneficial antioxidant and anti-inflammatory effects, their effects on blood platelet activation are poorly understood. Therefore, the aim of the present study was to determine the effect on platelet adhesion of preparations from selected cucurbits: pumpkin (Cucirbita pepo; fruit without seeds), zucchini (Cucurbita pepo convar. giromontina; fruit with seeds), cucumber (Cucumis sativus; fruit with seeds), white pattypan squash (Cucurbita pepo var. patisoniana; fruit without seeds) and yellow pattypan squash (Cucurbita pepo var. patisoniana, fruit without seeds). It also evaluates the activity of these preparations on enzymatic lipid peroxidation in thrombin-activated washed blood platelets by TBARS assay. The study also determines the anti-platelet and anticoagulant properties of these five cucurbit preparations in whole blood by flow cytometry and with the total thrombus-formation analysis system (T-TAS) and evaluates the cytotoxicity of the tested preparations against platelets based on LDH activity. The results indicate that the yellow Cucurbita pepo var. patisoniana preparation demonstrated stronger anti-platelet properties than the other tested preparations, reducing the adhesion of thrombin-activated platelets to collagen/fibrinogen, and inhibiting arachidonic acid metabolism and GPIIb/IIIa expression on 10 µM ADP-activated platelets. None of the preparations was found to cause platelet lysis. Our findings provide new information on the anti-platelet activity of the tested cucurbit preparations and their potential for treating CVDs associated with platelet hyperactivity.

Activation-dependent surface expression of gC1qR/p33 on human blood platelets

2003 ◽  
Vol 89 (02) ◽  
pp. 331-339 ◽  
Author(s):  
Tara Murphy ◽  
Berhane Ghebrehiwet ◽  
Ellinor Peerschke
Keyword(s):  
Amino Acids ◽  
Platelet Activation ◽  
Human Blood ◽  
Cultured Cells ◽  
Blood Platelets ◽  
Surface Membrane ◽  
Protein A ◽  
Activated Platelets ◽  
Terminal Amino ◽  
Human Blood Platelets

SummaryGC1qR/p33 (gC1qR) is expressed by a variety of somatic and cultured cells, including blood platelets. It interacts with several cellular, viral, bacterial, and plasma proteins, suggesting a potential role in thrombosis, inflammation, and infection. Considerable controversy has surrounded the surface membrane localization of gC1qR, however, since its cDNA sequence does not predict a traditional membrane-anchoring domain, and bears a typical mitochondrial targeting sequence. The present study examined gC1qR expression on resting and activated human blood platelets using flow cytometry and confocal microscopy with two monoclonal antibodies, 74.5.2 and 60.11, directed against gC1qR C-terminal amino acids 204-218, and N-terminal amino acids 76-93, respectively. Unstimulated platelets reacted minimally with either antibody. In contrast, platelet activation with TRAP, epinephrine, or ADP produced markedly increased gC1qR expression as reflected by 74.5.2 binding but not 60.11 binding. Platelet activation was verified using PAC-1 and anti CD 62 antibodies. Whereas PAC-1 binding to activated platelets could be reversed following platelet incubation with PGE1, 74.5.2 binding remained unchanged, suggesting the sustained expression of gC1qR following platelet stimulation. The data further demonstrate that detection of cell surface gC1qR may be dependent on antibody specificity. The ability of gC1qR to bind proteins involved in complement, coagulation, and kinin systems, as well as viral and bacterial pathogens including S. aureus protein A, supports the hypothesis that gC1qR expressed on activated platelets may contribute directly to thrombosis, inflammation, and endovascular infections.

scholarly journals Human Cytomegalovirus–Platelet Interaction Triggers Toll-Like Receptor 2–Dependent Proinflammatory and Proangiogenic Responses

2014 ◽  
Vol 34 (4) ◽  
pp. 801-809 ◽  
Author(s):  
Alice Assinger ◽  
Julia B. Kral ◽  
Koon C. Yaiw ◽  
Waltraud C. Schrottmaier ◽  
Ewa Kurzejamska ◽  
...  
Keyword(s):  
Growth Factor ◽  
Platelet Activation ◽  
Human Cytomegalovirus ◽  
Viral Reactivation ◽  
In Vivo Model ◽  
Vascular Endothelial ◽  
Toll Like Receptor ◽  
Wild Type ◽  
Tlr2 Expression ◽  
Activated Platelets

Objective— Human cytomegalovirus (HCMV) is a widespread pathogen that correlates with various clinical complications, including atherosclerosis. HCMV is released into the circulation during primary infection and periodic viral reactivation, allowing virus–platelet interactions. Platelets are important in the onset and development of atherosclerosis, but the consequences of platelet–HCMV interactions are unclear. Approach and Results— We studied the effects of HCMV–platelet interactions in blood from healthy donors using the purified clinical HCMV isolate VR1814. We demonstrated that HCMV bound to a Toll-like receptor (TLR) 2–positive platelet subpopulation, which resulted in signal transduction, degranulation, and release of proinflammatory CD40L and interleukin-1β and proangiogenic vascular endothelial–derived growth factor. In mice, murine CMV activated wild-type but not TLR2-deficient platelets. However, supernatant from murine CMV–stimulated wild-type platelets also activated TLR2-deficient platelets, indicating that activated platelets generated soluble mediators that triggered further platelet activation, independent of TLR2 expression. Inhibitor studies, using ADP receptor antagonists and apyrase, revealed that ADP release is important to trigger secondary platelet activation in response to HCMV. HCMV-activated platelets rapidly bound to and activated neutrophils, supporting their adhesion and transmigration through endothelial monolayers. In an in vivo model, murine CMV induced systemic upregulation of platelet–leukocyte aggregates and plasma vascular endothelial–derived growth factor in mice and showed a tendency to enhance neutrophil extravasation in a TLR2-dependent fashion. Conclusions— HCMV is a well-adapted pathogen that does not induce immediate thrombotic events. However, HCMV–platelet interactions lead to proinflammatory and proangiogenic responses, which exacerbate tissue damage and contribute to atherogenesis. Therefore, platelets might contribute to the effects of HCMV in accelerating atherosclerosis.

scholarly journals Preparations from selected cucurbit vegetables as antiplatelet agents

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Agata Rolnik ◽  
Bartosz Skalski ◽  
Anna Stochmal ◽  
Beata Olas
Keyword(s):  
Platelet Activation ◽  
Cucurbita Pepo ◽  
Fruits And Vegetables ◽  
Thrombus Formation ◽  
Blood Platelets ◽  
Antiplatelet Agents ◽  
Blood Platelet ◽  
Arachidonic Acid Metabolism ◽  
Platelet Activity ◽  
Activated Platelets

AbstractIncreased blood platelet activation plays an important role in cardiovascular diseases (CVDs). Recent experiments indicate that certain fruits and vegetables, including onion, garlic, and beetroot, have anti-platelet potential and therefore may reduce the likelihood of CVDs. While vegetables from the Cucuritaceae family are known to exerting beneficial antioxidant and anti-inflammatory effects, their effects on blood platelet activation are poorly understood. Therefore, the aim of the present study was to determine the effect on platelet adhesion of preparations from selected cucurbits: pumpkin (Cucurbita pepo; fruit without seeds), zucchini (Cucurbita pepo convar. giromontina; fruit with seeds), cucumber (Cucumis sativus; fruit with seeds), white pattypan squash (Cucurbita pepo var. patisoniana; fruit without seeds) and yellow pattypan squash (Cucurbita pepo var. patisoniana, fruit without seeds). It also evaluates the activity of these preparations on enzymatic lipid peroxidation in thrombin-activated washed blood platelets by TBARS assay. The study also determines the anti-platelet properties of these five cucurbit preparations in whole blood by flow cytometry and with the total thrombus-formation analysis system (T-TAS) and evaluates the cytotoxicity of the tested preparations against platelets based on LDH activity. The results indicate that the yellow Cucurbita pepo var. patisoniana preparation demonstrated stronger anti-platelet properties than the other tested preparations, reducing the adhesion of thrombin-activated platelets to collagen/fibrinogen, and inhibiting arachidonic acid metabolism and GPIIb/IIIa expression on 10 µM ADP-activated platelets. None of the preparations was found to cause platelet lysis. Our findings provide new information on the anti-platelet activity of the tested cucurbit preparations and their potential for treating CVDs associated with platelet hyperactivity.

Sign in / Sign up

Export Citation Format

Share Document