Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tissue factor pathway inhibitor (TFPI) plays an important role in inhibiting tissue factor-induced coagulation by a factor Xadependent pathway of the activated tissue-factor VIIa complex. Decreased values of the latter inhibitor have been recently reported in adult patients with venous thrombosis (VT) or ischaemic stroke (IS). The present case-control study was therefore performed to evaluate whether a decreased TFPI concentration is also involved in paediatric symptomatic thromboembolism (ST). Total TFPI concentrations were measured along with established prothrombotic risk factors six to twelve months after the acute thrombotic onset in 144 Caucasian children aged 0.6 to 18 years (VT: n=80; IS: n=64). The cut-off values defined as age-dependent 10(th) percentiles were obtained from 244 healthy controls. Median (range) values of TFPI were significantly lower in patients compared with control subjects [50.0(20.0-132.3) ng/ml vs. 59.5(25.4-117.4) ng/ml; p-value < 0.0001]. In addition, 42 of the 144 patients (29.2%) compared with 25 of the 244 controls (10.2%) showed TFPI concentrations below the 10(th) age-dependent percentiles. Compared to baseline values 78.6% of children with total TFPI Ag < 10(th) percentiles showed a low response to enoxaparin administration, whereas in children with normal baseline TFPI values 30% show a low TFPI release (p = 0.007). Multivariate analysis adjusted for the presence of established prothrombotic risk factors showed a significantly increased odds ratio (OR) and 95% confidence interval (CI) for patients with ST [OR/CI: 3.8/2.2-6.6; p < 0.0001]. Data shown here give evidence that total TFPI concentrations below the 10(th) age-dependent percentiles independently increase the risk of ST in Caucasian children 3.8-fold.
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PMID:Total tissue factor pathway inhibitor is an independent risk factor for symptomatic paediatric venous thromboembolism and stroke. 1546 99

The Kunitz-type proteinase inhibitor, tissue factor pathway inhibitor (TFPI), is the only endogenous inhibitor of the tissue factor (TF)-mediated coagulation pathway that plays a dominant role in normal haemostasis. TFPI exerts its action by binding to factor Xa (FXa) forming a TFPI-FXa complex that then, in a second step, binds and effectively inhibits the TF-factor VIIa (FVIIa) complex. Both full-length TFPI and chemically modified forms (e.g., truncated, glycosylated or phosphorylated TFPI variants) exert various pharmacological effects. The anticoagulant and antiplatelet actions of TFPI, its potency in inhibiting thrombin and FXa generation, as well as its favourable antithrombotic effectiveness seen in different animal models of venous and arterial thrombosis make this inhibitor a promising agent that could be potentially useful in several clinical indications. The inhibitory action of TFPI is accelerated by heparin. Heparin, as well as low molecular weight heparin (LMWH) derivatives, release TFPI from the vascular endothelium, an effect which seems to contribute mainly to the antithrombotic effectiveness of these drugs. The clinical relevance of TFPI is still undefined. Based on the beneficial actions in animal studies, as well as on the results obtained in first clinical investigations, TFPI is expected to be effective in the treatment of various diseases, such as disseminated intravascular coagulation, sepsis, coronary syndromes, stroke and acute respiratory distress syndrome (ARD). Further clinical trials should clarify the role of TFPI and more importantly define its potential usefulness as a prophylactic and/or therapeutic agent.
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PMID:Recombinant TFPI and variants: potential implications in the treatment of cardiovascular disorders. 1599 20

To explore the role of the the tissue factor (TF) pathway in ischemic stroke. We measured blood concentrations of markers of the TF pathway [TF antigen, free tissue factor pathway inhibitor antigen (TFPIf) and activity (TFPIac), and activated factor VII (FVIIa)] within 7 days (acute phase) and after 3-6 months (convalescence) in 150 patients with first-ever ischemic stroke and 150 community controls. During the acute phase, TF antigen and TFPIf were not significantly altered but TFPIac was increased (mean 1.27 versus 1.13 U/ml, P = 0.04) and FVIIa was decreased in cases compared with controls (mean 43.3 versus 57.9 mU/ml, P = 0.0004). After adjusting for baseline differences between cases and controls, increasing quartiles of TFPIf were independently associated with reduced odds of stroke, and reducing quartiles of FVIIa and increasing quartiles of TFPIac with increased odds of stroke. During the convalescent phase, FVIIa and TFPIac returned to normal but TF antigen and TFPIf were significantly decreased compared with controls [median TF antigen, 110 (follow-up) versus 155 pg/ml (controls), P = 0.0008; median TFPIf, 15.5 (follow-up) versus 23.3 ng/ml (controls), P = 0.002]. Alterations of blood concentrations of TF pathway markers are common in patients with acute ischemic stroke. The mechanisms are unclear but may relate to enhanced formation of TF-FVIIa complexes and upregulation and release of TFPI during the acute phase, and ongoing consumption of TF antigen and TFPIf during the chronic phase as the atherosclerotic plaque heals.
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PMID:The tissue factor pathway in ischemic stroke. 1698 46

Epidemiological studies have linked levels of particulate matter (PM) in ambient air to cardiovascular mortality and hospitalizations for myocardial infarction (MI) and stroke. Thrombus formation plays a primary role in potentiating acute cardiovascular events, and this study was undertaken to determine whether pulmonary exposure to PM alters hemostasis. PM was collected from the Chapel Hill, NC airshed and was administered to mice by intratracheal instillation at a dose previously shown to exacerbate myocardial ischemia-reperfusion injury. Twenty-four hours after exposure, an increase occurred in the number of circulating platelets and plasma concentrations of fibrinogen and soluble P-selectin. The concentration of tissue factor pathway inhibitor (TFPI) in plasma was decreased, whereas the plasma concentration of plasminogen activator inhibitor (PAI-1) was increased. Consistent with these observations, bleeding time from a tail-tip transection was shortened. These results provide evidence that PM exposure alters hemostasis in otherwise healthy animals and may thereby promote clot formation and impede clot resolution in susceptible individuals. The results also establish definite hemostatic endpoints that can be used to further investigate the effects of dose and particle characteristics on the toxicity of ambient particles.
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PMID:Effect of ambient particulate matter exposure on hemostasis. 1754 51

The present study aimed to determine whether four previously described polymorphisms found within the tissue factor pathway inhibitor (TFPI) gene are associated with free plasma TFPI levels or with TFPI activity as well as the risk of ischaemic stroke in stroke patients and control individuals. We conducted a case-control study of 162 first-ever ischaemic stroke cases and 170 randomly selected community control individuals. The TFPI genotype was determined for the T-287C, C-399T, Intron 7 C-33T, and Val264Met (G874A) polymorphisms. Free plasma TFPI and TFPI activity were measured during the first 7 days and 3-6 months after the acute stroke event. Free plasma TFPI levels were significantly lowered 3-6 months after stroke compared with levels observed in the patient group during the acute phase of the stroke (mean, 16.3 versus 22.46 ng/ml; P = 0.046) and among the control group (mean, 16.3 versus 22.79 ng/ml; P < 0.0001). Conversely, TFPI activity was significantly up-regulated during the acute phase (mean, 1.30 versus 1.11 U/ml; P = 0.0051) and remained elevated 3-6 months later (mean, 1.28 versus 1.11 U/ml; P = 0.03). The TFPI gene polymorphisms studied were not significantly associated with TFPI levels or activity, nor with the risk of ischaemic stroke. In conclusion, the TFPI activity and concentration in plasma varied significantly after an ischaemic stroke; however, these variations were not found to be due to the presence of any of the genetic mutations analysed in this study. Our results are consistent with the emerging model suggesting the lipoprotein-bound portion of TFPI has a significant influence on coagulation and diseases of haemostasis.
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PMID:Polymorphisms in the tissue factor pathway inhibitor gene are not associated with ischaemic stroke. 1789 Sep 62

Ischaemia/reperfusion (I/R) injury is central to a number of pathologies including myocardial infarction and stroke. Several cellular processes are involved in the progress of I/R injury, involving complex interactions between coagulation and inflammatory or apoptotic processes. Besides for their anti-coagulant function, anticoagulant proteins such as activated protein C (APC), active site inhibited factor VIIa (ASIS), tissue factor pathway inhibitor (TFPI), and antithrombin (AT) are also known for their anti-inflammatory or cell protective effects. This review gives an overview of the application of these anti-coagulants in several animal models of I/R injury in critical organs and describes the effects of these proteins on cellular processes including inflammation and apoptosis. The future testing of mutant forms of some of these inhibitors including APC in a clinical setting should be actively explored.
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PMID:Anticoagulant therapy in critical organ ischaemia/reperfusion injury. 2043 46

Blood neutrophils provide the first line of defense against pathogens but have also been implicated in thrombotic processes. This dual function of neutrophils could reflect an evolutionarily conserved association between blood coagulation and antimicrobial defense, although the molecular determinants and in vivo significance of this association remain unclear. Here we show that major microbicidal effectors of neutrophils, the serine proteases neutrophil elastase and cathepsin G, together with externalized nucleosomes, promote coagulation and intravascular thrombus growth in vivo. The serine proteases and extracellular nucleosomes enhance tissue factor- and factor XII-dependent coagulation in a process involving local proteolysis of the coagulation suppressor tissue factor pathway inhibitor. During systemic infection, activation of coagulation fosters compartmentalization of bacteria in liver microvessels and reduces bacterial invasion into tissue. In the absence of a pathogen challenge, neutrophil-derived serine proteases and nucleosomes can contribute to large-vessel thrombosis, the main trigger of myocardial infarction and stroke. The ability of coagulation to suppress pathogen dissemination indicates that microvessel thrombosis represents a physiological tool of host defense.
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PMID:Reciprocal coupling of coagulation and innate immunity via neutrophil serine proteases. 2108 May 76

Elevated resistance and reduced compliance of the pulmonary vasculature increase right ventricular (RV) afterload. Local and systemic inflammation and haemostatic abnormalities are prominent in pulmonary vascular diseases. We hypothesized that plasma biomarker levels indicating greater inflammation and coagulability associated with pulmonary vascular disease would be associated with RV structure and function measured by cardiac magnetic resonance imaging (MRI). The Multi-Ethnic Study of Atherosclerosis (MESA) performed cardiac MRI among participants aged 45-84 years without clinical cardiovascular disease. We assessed the associations of RV mass, RV end-diastolic volume (RVEDV), RV stroke volume (RVSV) and RV ejection fraction (RVEF) with plasma measures of inflammation (matrix metalloproteinase (MMP)-3 and -9, intercellular adhesion molecule (ICAM)-1, tumour necrosis factor receptor (TNF-R1), and E-selectin) and thrombosis (plasminogen activator inhibitor (PAI)-1, tissue factor, tissue factor pathway inhibitor and CD40 ligand).The study sample included 731 subjects. Higher MMP-9 levels were associated with lower RV mass before and after adjustment for left ventricular (LV) mass (p=0.008 and p=0.044, respectively). Higher levels of MMP-9 and PAI-1 were also associated with smaller RVEDV (p<0.05). Higher PAI-1 levels were associated with lower RVEF even after adjustment for LV ejection fraction (p=0.017). In conclusion, MMP-9 and PAI-1 are associated with changes in RV structure and function which could be potentially related to a subclinical increase in pulmonary vascular resistance.
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PMID:Matrix metalloproteinase-9 and plasminogen activator inhibitor-1 are associated with right ventricular structure and function: the MESA-RV Study. 2092 24

Tissue factor pathway inhibitor (TFPI) is the main inhibitor of tissue factor (TF)-mediated coagulation. In atherosclerotic plaques TFPI co-localizes with TF, where it is believed to play an important role in attenuating TF activity. Findings in animal models such as TFPI knockout models and gene transfer models are consistent on the role of TFPI in arterial thrombosis as they reveal an active role for TFPI in attenuating arterial thrombus formation. In addition, ample experimental evidence exists indicating that TFPI has inhibitory effects on both smooth muscle cell migration and proliferation, both which are recognized as important pathological features in atherosclerosis development. Nonetheless, the clinical relevance of these antithrombotic and atheroprotective effects remains unclear. Paradoxically, the majority of clinical studies find increased instead of decreased TFPI antigen and activity levels in atherothrombotic disease, particularly in atherosclerosis and coronary artery disease (CAD). Increased TFPI levels in cardiovascular disease might result from complex interactions with established cardiovascular risk factors, such as hypercholesterolemia, diabetes and smoking. Moreover, it is postulated that increased TFPI levels reflect either the amount of endothelial perturbation and platelet activation, or a compensatory mechanism for the increased procoagulant state observed in cardiovascular disease. In all, the prognostic value of plasma TFPI in cardiovascular disease remains to be established. The current review focuses on TFPI in clinical studies of asymptomatic and symptomatic atherosclerosis, coronary artery disease and ischemic stroke, and discusses potential atheroprotective actions of TFPI.
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PMID:The role of tissue factor pathway inhibitor in atherosclerosis and arterial thrombosis. 2363 10

The lectin pathway (LP) of complement has a protective function against invading pathogens. Recent studies have also shown that the LP plays an important role in ischemia/reperfusion (I/R)-injury. MBL-associated serine protease (MASP)-2 appears to be crucial in this process. The serpin C1-inhibitor is the major inhibitor of MASP-2. In addition, aprotinin, a Kunitz-type inhibitor, was shown to inhibit MASP-2 activity in vitro. In this study we investigated whether the Kunitz-type inhibitor tissue factor pathway inhibitor (TFPI) is also able to inhibit MASP-2. Ex vivo LP was induced and detected by C4-deposition on mannan-coated plates. The MASP-2 activity was measured in a fluid-phase chromogenic assay. rTFPI in the absence or presence of specific monoclonal antibodies was used to investigate which TFPI-domains contribute to MASP-2 inhibition. Here, we identify TFPI as a novel selective inhibitor of MASP-2, without affecting MASP-1 or the classical pathway proteases C1s and C1r. Kunitz-2 domain of TFPI is required for the inhibition of MASP-2. Considering the role of MASP-2 in complement-mediated I/R-injury, the inhibition of this protease by TFPI could be an interesting therapeutic approach to limit the tissue damage in conditions such as cerebral stroke, myocardial infarction or solid organ transplantation.
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PMID:TFPI inhibits lectin pathway of complement activation by direct interaction with MASP-2. 2535 15


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