Effect of ionizing radiation on procoagulant activity
Ontology highlight
ABSTRACT: Ionizing radiation (IR) is associated with thrombotic vascular occlusion. Thrombosis in malignancy predicts a poor clinical outcome. Tissue factor (TF) is the initiator of the extrinsic co-agulation system and induces thrombus formation. Our study examined whether IR induced TF expression and procoagulability in the myelomonocytic leukemia THP-1 cell model. We further investigated coordinated gene alterations associated with TF upregulation and IR-induced thrombogenicity. Gene expression profiling revealed IR to increase the expression of inflammatory and apoptosis-related pathways, contributing to TF upregulation and increased TF procoagulability on day 7 post IR. The upregulation of these pathways together with TF upregulation contributed to the increased thrombogenic potential of tissues post application of IR. Keywords: irridiation response
Project description:Ionizing radiation (IR) is associated with thrombotic vascular occlusion. Thrombosis in malignancy predicts a poor clinical outcome. Tissue factor (TF) is the initiator of the extrinsic co-agulation system and induces thrombus formation. Our study examined whether IR induced TF expression and procoagulability in the myelomonocytic leukemia THP-1 cell model. We further investigated coordinated gene alterations associated with TF upregulation and IR-induced thrombogenicity. Gene expression profiling revealed IR to increase the expression of inflammatory and apoptosis-related pathways, contributing to TF upregulation and increased TF procoagulability on day 7 post IR. The upregulation of these pathways together with TF upregulation contributed to the increased thrombogenic potential of tissues post application of IR. Experiment Overall Design: THP-1 cells were harvested on day 3 (1 sample) and day 7 (3 samples) post irradiation. For each time point untreated control samples were run.
Project description:Atrial fibrillation (AF) is a major risk factor for cardioembolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern particularly when antiplatelet treatment is simultaneously administered. Here, microarray analysis in peripheral blood cells in eight patients with AF and stroke and eight AF subjects without stroke identified a stroke related gene expression pattern. HSPA1B, which encodes for heat-shock protein 70 kDa (Hsp70), was the most differentially expressed gene. This gene was downregulated in stroke subjects, a finding confirmed further in an independent AF cohort of 200 individuals. Hsp70 knock-out (KO) mice subjected to different thrombotic challenges developed thrombosis significantly earlier than their wild-type (WT) counterparts. In WT mice, Hsp70 inducers (TRC051384, or tubastatin A) delayed thrombus formation. Remarkably, Hsp70 inducers did not increase the bleeding risk even when aspirin was concomitantly administered. Hsp70 induction was associated with an increased vascular thrombomodulin expression, higher circulating levels of activated protein C (APC) upon thrombotic stimulus and increased protection against endothelial apoptosis. Thus, Hsp70 induction is a novel approach to delay thrombus formation with minimal bleeding risk, being especially promising in situations where there is a major bleeding hazard. Microarray analysis in peripheral blood cells includes eight patients with AF and stroke and eight AF subjects without stroke
Project description:Blood-contacting medical implants made of Nitinol and other titanium alloys, such as neurovascular flow diverters and peripheral stents, have the disadvantage of being highly thrombogenic. This makes the use of systemic (dual) anti platelet / anticoagulant therapies inevitable with related risks of device thrombosis, bleeding and other complications. Meeting the urgent clinical demand for a less thrombogenic Nitinol surface, we describe here a treatment of standard, commercially available Nitinol that renders its surface ultra-hydrophilic and functionalized with phosphate ions. The efficacy of this treatment was assessed by comparing standard and surface-treated Nitinol disks and braids, equivalent to flow diverters. Static and dynamic (Chandler loop) blood incubation tests showed a drastic reduction of thrombus formation on treated devices. Surface chemistry and proteomic analysis indicated a key role of phosphate and calcium ions in steering blood protein adsorption and avoiding coagulation cascade activation and platelet adhesion. A good endothelialization of the surface confirmed the biocompatibility of the treated surface.
Project description:Cancer patients often have an activated clotting system and are at increased risk for venous thrombosis. In this study, we analyzed tissue factor (TF) expression in four different human pancreatic tumor cell lines for the purpose of producing derivative tumors in vivo. We found that two of the lines expressed TF and released TF-positive microparticles (MPs) into the culture medium. The majority of TF protein in the culture medium was associated with MPs. Importantly, only TF-positive cell lines activated coagulation in nude mice, and this activation was abolished by an anti-human TF antibody. Of the two TF-positive lines only one produced detectable levels of human MP TF activity in the plasma when grown orthotopically in nude mice. Surprisingly, <5% of human TF protein in plasma from tumor-bearing mice was associated with MPs. Mice with TF-positive tumors and elevated levels of circulating TF-positive MPs had increased thrombosis in a saphenous vein model. In contrast, we observed no difference in thrombus weight between tumor bearing and control mice in an inferior vena cava stenosis model. Our studies suggest that in a xenograft mouse model tumor TF activates coagulation, whereas TF on circulating MPs may trigger venous thrombosis.
Project description:Atrial fibrillation (AF) is a major risk factor for cardioembolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern particularly when antiplatelet treatment is simultaneously administered. Here, microarray analysis in peripheral blood cells in eight patients with AF and stroke and eight AF subjects without stroke identified a stroke related gene expression pattern. HSPA1B, which encodes for heat-shock protein 70 kDa (Hsp70), was the most differentially expressed gene. This gene was downregulated in stroke subjects, a finding confirmed further in an independent AF cohort of 200 individuals. Hsp70 knock-out (KO) mice subjected to different thrombotic challenges developed thrombosis significantly earlier than their wild-type (WT) counterparts. In WT mice, Hsp70 inducers (TRC051384, or tubastatin A) delayed thrombus formation. Remarkably, Hsp70 inducers did not increase the bleeding risk even when aspirin was concomitantly administered. Hsp70 induction was associated with an increased vascular thrombomodulin expression, higher circulating levels of activated protein C (APC) upon thrombotic stimulus and increased protection against endothelial apoptosis. Thus, Hsp70 induction is a novel approach to delay thrombus formation with minimal bleeding risk, being especially promising in situations where there is a major bleeding hazard.
Project description:<p><strong>BACKGROUND AND AIMS:</strong> The increasing incidence of cardiovascular diseases has created an urgent need for safe and effective anti-thrombotic agents. Leech, as a traditional Chinese medicine, has the effect of promoting blood circulation and removing blood stasis, but its real material basis and mechanism of action for the treatment of diseases such as blood stasis and thrombosis have not been reported.</p><p><strong>METHODS:</strong> In this study, <em>Whitmania Pigra Whitman</em> (WPW), <em>Hirudo nipponica Whitman</em> (HNW) and <em>Whitmania acranutata Whitman</em> (WAW) were hydrolyzed by biomimetic enzymatic hydrolysis to obtain the active peptides of WPW (APP), the active peptides of HNW (APH) and the active peptides of WAW (APA), respectively. Then their structures were characterized by sykam amino acid analyzer, fourier transform infrared spectrometer (FT-IR), circular dichroism (CD) spectrometer and LC-MS. Next, the anti-thrombotic activities of APP, APH and APA were determined by carrageenan-induced tail vein thrombosis model in mice, and the anti-thrombotic mechanisms of high-dose APP group (HAPP), high-dose APH group (HAPH) and high-dose APA group (HAPA) were explored based on UHPLC-Q-Exactive Orbitrap mass spectrometry.</p><p><strong>RESULTS:</strong> The results showed that the amino acid composition of APP, APH and APA was consistent, and the proportion of each amino acid was few different. The results of FT-IR and CD showed that there were no significant differences in the proportion of secondary structures (such as β-sheet and random coil) and infrared absorption peaks between APP, APH and APA. Mass spectrometry data showed that there were 43 common peptides in APP, APH and APA, indicating that the three have common material basis. APP, APH and APA could significantly inhibit platelet aggregation, reduce black-tail length, whole blood viscosity (WBV), plasma viscosity (PV), and Fibrinogen (FIB), and prolong coagulation time, including activated partial thrombin time (APTT), prothrombin time (PT) and thrombin time (TT). In addition, 24 metabolites were identified as potential biomarkers associated with thrombosis development. Among these, 19, 23, and 20 metabolites were significantly normalized after administration of HAPP, HAPH, and HAPA in the mice, respectively. Furthermore, the intervention mechanism of HAPP, HAPH and HAPA on tail vein thrombosis mainly involved in linoleic acid metabolism, primary bile acid biosynthesis and ether lipid metabolism.</p><p><strong>CONCLUSION:</strong> Our findings suggest that APP, APH and APA can exert their anti-blood stasis and anti-thrombotic activities by interfering with disordered metabolic pathways in vivo, and there is no significant difference in their efficacies.</p>
Project description:Recent advancements have identified numerous long non-coding RNAs (lncRNAs) involved in various biological processes and diseases. However, the roles of lncRNAs in venous thromboembolism (VTE) remain largely unexplored. This study aims to elucidate the expression profiles of lncRNAs and mRNAs in a well-established animal model of VTE. Acute thrombosis was induced by surgical ligation of the inferior vena cava (IVC) within 24 hours. The thrombus burden in venous vessels was evaluated using hematoxylin and eosin staining and Masson's trichrome staining. The IVC and associated thrombus were harvested 24 hours post-ligation, and the extracted RNA was subjected to RNA sequencing (RNA-seq) analysis. This study offers a comprehensive overview of the expression profiles of lncRNAs and mRNAs in a murine model of venous thrombosis, providing novel insights into the roles of RNAs in VTE.
Project description:Arterial and venous (A/V) thrombosis constitutes the greatest source of morbidity and mortality worldwide. Long considered as distinct entities, accumulating evidence indicates that A/V thrombosis can occur in the same populations suggesting that common mechanisms are likely operative. Although hyperactivation of the immune system is a common forerunner to the genesis of thrombotic events in both vascular systems, the key molecular control points remain poorly understood. Consequently, anti-thrombotic therapies targeting the immune system for therapeutic gain are lacking. Here we show that neutrophils are key effectors of both A/V thrombosis and can be targeted via novel immunoregulatory nanoparticles. Using antiphopholipid antibody syndrome (APS) as a model for devastating A/V thrombosis, we identified the transcription factor Krüppel-like factor 2 (KLF2) as a key regulator of neutrophil activation. Upon activation via genetic loss of KLF2 or administration of antiphospholipid antibodies, neutrophils cluster P-selectin glycoprotein ligand 1 (PSGL-1) via cortical actin remodeling, thereby increasing adhesion potential at thrombosis sites. Targeting clustered PSGL-1 using designer nanoparticles attenuates neutrophil-mediated A/V thrombosis in APS and KLF2 knockout models, illustrating the importance and feasibility of targeting activated neutrophils to prevent pathological thrombosis. Together, our results demosntrate a role for activated neutrophils to prevent pathological thrombosis. Together, our results demonstrate a role for activated neutorphils in both arterial and venous thrombosis and identify key molecular events that serve as potential targets for therapeutics against diverse causes of immunothrombosis.
Project description:The antiphospholipid syndrome (APS) is an autoimmune disease in which antiphospholipid antibodies (aPL) cause vascular thrombosis (VT+) and/or pregnancy morbidity (PM+). The experiment aimed at determining whether specific aPL are associated with thrombotic or obstetric manifestations. In the present study we carried out microarray analysis comparing patterns of mRNA expression in monocytes from a healthy volunteer exposed to IgG from patients with a history of vascular thrombosis (VT+/PM-) or pregnancy morbidity (VT-/PM+) or to IgG from healthy controls (HC).
Project description:Hyperlipidemia is a well-established risk factor for cardiovascular diseases. Trillions of people worldwide display mildly elevated levels of plasma lipids and cholesterol due to diet and life-style. The relationship between severe hyperlipidemia and thrombosis has been extensively investigated, but the effects of the preliminary stages of hyperlipidemia on platelet function are unclear. Therefore, we investigated how moderate elevation of different plasma lipid profiles influence platelet activation and thrombus formation, as compared to higher plasma lipid concentrations. Hyperlipidemic Apoe-/- and Ldlr-/- and wild-type mice were fed a normal chow diet, resulting in mildly increased plasma cholesterol. Blood from both knockout mice was used in comparison to wild-type mice, for multiparameter ex vivo measurements of thrombus formation under flow. Whole blood (fibrin-)thrombus formation on collagen in the absence or presence of coagulation (with(out) tissue factor), indicated enhancement of the thrombotic process in both knockout mice. These effects were not further aggravated in aged mice, as well as in Apoe-/- mice on high fat diet with very high plasma cholesterol levels. Bone marrow chimeras of wild-type or Ldlr-/- platelets into irradiated Ldlr-/- recipient mice showed similar thrombus formation patterns. This suggested that hyperlipidemia itself, not the platelet LDL receptor deficiency is responsible for the altered platelet activation status in Ldlr-/- mice. Exploration of the platelet proteome revealed high similarity between the three genotypes, although some proteins showed significantly changed expression in Apoe-/- mice. Finally, platelet lipidomic analysis showed an increased lipid profile in mildly hyperlipidemic mice, which may further contribute to the observed prothrombotic phenotype