Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tissue factor (TF), formerly known as thromboplastin, is the key initiator of the coagulation cascade; it binds factor VIIa resulting in activation of factor IX and factor X, ultimately leading to fibrin formation. TF expression and activity can be induced in endothelial cells, vascular smooth muscle cells, and monocytes by various stimuli such as cytokines, growth factors, and biogenic amines. These mediators act through diverse signal transduction mechanisms including MAP kinases, PI3-kinase, and protein kinase C. Cellular TF is present in three pools as surface, encrypted, and intracellular protein. TF can also be detected in the bloodstream, referred to as circulating or blood-borne TF. Elevated levels of TF are observed in patients with cardiovascular risk factors such as hypertension, diabetes, dyslipidemia, and smoking as well as in those with acute coronary syndromes. TF may indeed be involved in the pathogenesis of atherosclerosis by promoting thrombus formation; in addition, it can induce migration and proliferation of vascular smooth muscle cells. As a consequence, therapeutic strategies have been developed to specifically interfere with the action of TF such as antibodies against TF, site-inactivated factor VIIa, or recombinant TF pathway inhibitor. Inhibition of TF action appears to be an attractive target for the treatment of cardiovascular diseases.
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PMID:Tissue factor in cardiovascular diseases: molecular mechanisms and clinical implications. 1646 45

The stress-responsive serum- and glucocorticoid-inducible kinase Sgk-1 is involved in osmoregulation and cell survival and may contribute to fibrosis and hypertension. However, the function of Sgk-1 in vascular remodeling and thrombosis, 2 major determinants of pulmonary hypertension (PH), has not been elucidated. We investigated the role of Sgk-1 in thrombin signaling and tissue factor (TF) expression and activity in pulmonary artery smooth muscle cells (PASMC). Thrombin increased Sgk-1 activity and mRNA and protein expression. H2O2 similarly induced Sgk-1 expression. Antioxidants, dominant-negative Rac, and depletion of the NADPH oxidase subunit p22phox diminished thrombin-induced Sgk-1 expression. Inhibition of p38 mitogen-activated protein kinase, phosphatidylinositol 3-kinase, and phosphoinositide-dependent kinase-1 prevented thrombin-induced Sgk-1 expression. Thrombin or Sgk-1 overexpression enhanced TF expression and procoagulant activity, whereas TF upregulation by thrombin was diminished by kinase-deficient Sgk-1 and was not detectable in fibroblasts from mice deficient in sgk-1 (sgk1(-/-)). Similarly, dexamethasone treatment failed to induce TF expression and activity in lung tissue from sgk1(-/-) mice. Transcriptional induction of TF by Sgk-1 was mediated through nuclear factor kappaB. Finally, Sgk-1 and TF proteins were detected in the media of remodeled pulmonary vessels associated with PH. These data show that thrombin potently induces Sgk-1 involving NADPH oxidases, phosphatidylinositol 3-kinase, p38 mitogen-activated protein kinase, and phosphoinositide-dependent kinase-1, and that activation of nuclear factor kappaB by Sgk-1 mediates TF expression and activity by thrombin. Because enhanced procoagulant activity can promote pulmonary vascular remodeling, and Sgk-1 and TF were present in the media of remodeled pulmonary vessels, this pathway may play a critical role in vascular remodeling in PH.
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PMID:The serum- and glucocorticoid-inducible kinase Sgk-1 is involved in pulmonary vascular remodeling: role in redox-sensitive regulation of tissue factor by thrombin. 1648 15

A new hypothesis is presented on the function of factor XII, which is postulated to be a "missing link" between acute stress and transient hypercoagulability. The implications of this idea are developed to show how chronic stress, which involves activation of hypertension and migraine as well as hypercoagulability, can cause of cerebrovascular disease. "Acute stress" is defined as "the normal short-term physiological response to the perception of major threats or demands". "Chronic stress" is "the abnormal ongoing physiological response to the continuing perception of unresolvable major threats or demands". The factor XII hypothesis is as follows: Acute stress includes release of epinephrine by the adrenal medulla. Epinephrine activates platelets by binding to alpha-2A adrenergic receptors. Activated platelets convert pre-bound factor XII to its active form, which then initiates the intrinsic coagulation cascade. This can be called the "activated platelet initiation pathway" for coagulation. Neither tissue factor nor pre-formed thrombin is required. Thrombosis proceeds to completion, but only a minute amount of thrombin is formed, and the process normally stops at this point. In people who lapse into a state of chronic stress, essential hypertension, which is also a manifestation of stress, synergizes with hypercoagulability: there is both a baseline rise in blood pressure and systemic platelet activation as well as superimposed labile rises of both. Upregulation of these two stress parameters is atherogenic: epinephrine-activated platelets stimulating thrombin formation interact with endothelial cells activated by angiotensin II to cause, first, smooth muscle cell proliferation, which is a histological hallmark of atherosclerosis, and, lastly, a symptomatic thrombotic occlusion-the stroke. The migraine symptoms which often accompany this process are a marker of chronic stress and ongoing pathophysiologic damage. Therapeutic predictions are made regarding novel ways of blocking stress-induced hypercoagulability and hypertension. Hypercoagulability could be targeted by monoclonal antibodies directed against the platelet-specific alpha-2 adrenergic receptor or the (putative) platelet receptor for Factor XII; hypertension could be treated with monoclonal antibodies directed against the beta-adrenergic receptor in the juxtaglomerular apparatus or by surgical denervation of the kidneys, either of which would decrease the renin release which helps drive the hypertension.
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PMID:Factor XII (Hageman factor) is a missing link between stress and hypercoagulability and plays an important role in the pathophysiology of ischemic stroke. 1675 26

Severe pulmonary arterial hypertension (PAH) occurs in idiopathic form and in association with diverse diseases. The pathological hallmarks are distal smooth muscle hypertrophy, obliteration of small pulmonary arteriole lumens, and disorganized cellular proliferation in plexiform lesions. In situ thrombosis is also observed. A detailed understanding of the disease progression has been hampered by the absence of an animal model bearing all the pathological features of human disease. To create a model with these characteristics, we gave young (200-g) rats monocrotaline 1 wk following left pneumonectomy; controls with vehicle treatment or sham operation were also studied. In experimental rats, pulmonary arteries had distal smooth muscle hypertrophy and proliferative perivascular lesions. The lesions had a plexiform appearance, occurred early in disease development, and were composed of cells expressing endothelial antigens. Three-dimensional microangiography revealed severe vascular pruning and disorganized vascular networks. We found that expression of tissue factor (TF), the membrane glycoprotein that initiates coagulation, facilitates angiogenesis, and mediates arterial injury in the systemic circulation, was increased in the pulmonary arterioles and plexiform-like lesions of the rats. TF was also heavily expressed in the vessels and plexiform lesions of humans with pulmonary arterial hypertension. We conclude that plexiform-like lesions can be reproduced in rats, and this model will facilitate experiments to address controversies about the role of these lesions in PAH. Increased TF expression may contribute to the prothrombotic diathesis and vascular cell proliferation typical of human disease.
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PMID:Plexiform-like lesions and increased tissue factor expression in a rat model of severe pulmonary arterial hypertension. 1766 Mar 27

Several studies have indicated association between hematologic markers and increased risks of cerebrovascular disease, but few reports referred to their roles together. We studied plasma levels of 16 hematologic markers in 50 cases diagnosed as acute cerebral infarction (ACI) and 54 hospital control subjects. Plasma levels of thrombomodulin, fibrinogen, and activity of tissue factor (aTF) were significantly higher in cases than in control subjects (P < .001, P < .01, and P < .05, respectively). Multivariate logistic regression analysis showed that hypertension and high plasma levels of thrombomodulin, fibrinogen, and aTF were significantly associated with presence of ACI (odds ratio [OR], 143.74, P < .001; OR, 2.05, P < .05; OR, 2.09, P < .05; OR, 1.02, P < .05, respectively). Our findings indicate that hypertension and elevation of plasma thrombomodulin, fibrinogen, and aTF are independent risk factors for ACI.
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PMID:Plasma thrombomodulin, fibrinogen, and activity of tissue factor as risk factors for acute cerebral infarction. 1763 64

We tested the hypothesis that selected prothrombotic biomarkers might be associated with early spontaneous coronary recanalization in patients with ST-segment elevation acute myocardial infarction (STEMI). We prospectively enrolled 123 patients with STEMI including 53 patients with spontaneous coronary recanalization (cases) and 70 patients with persistent occlusion (controls) at the time of emergent coronary angiography and before angioplasty. All had received aspirin and heparin. Blood samples were collected immediately before angioplasty to measure soluble P-selectin, circulating microparticles originating from platelets (PMPs), granulocytes (GMPs), endothelial cells (EMPs); tissue factor-associated MP (TF-MP); soluble platelet glycoprotein V (sGPV) and prothrombin F1 + 2; tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI-1) and plasmin-antiplasmin (PAP). A sub-group of 70 patients (35 cases, 35 controls) was available for flow cytometry analysis of platelet P-selectin and activated GPIIb-IIIa. Baseline clinical characteristics did not differ between groups except for more frequent hypertension and dyslipidemia in controls. Platelet activation markers and PMP did not differ between the two groups. Controls had higher numbers of EMPs and GMPs compared to cases, but the difference was no longer significant when corrected for risk factors. Controls differed from cases by higher plasma levels of sGPV [64 (47-84) ng/ml vs. 53 (44-63) ng/ml] and PAP [114(65-225) ng/ml vs. 88 (51-147) ng/ml]. The difference persisted after adjustment for risks factors (p = 0.031 and 0.037, respectively). Persistent occlusion of the infarct related artery is associated with some markers related to higher thrombin (sGPV) and plasmin (PAP) production but is not associated with markers of platelet activation.
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PMID:Prothrombotic markers and early spontaneous recanalization in ST-segment elevation myocardial infarction. 1772 26

The adipocyte metabolism has been shown to change during the fat enlargement process associated to obesity. Several procoagulant proteins such as plasminogen activator inhibitor type 1, tissue factor or factor VII and also inducible nitric oxide synthase show higher expression in adipose tissue of obese people in comparison to lean. This overexpression could explain at least a part of the atherogenic and cardiovascular risk associated with obesity. In addition to cytokine secretion, many other features have been observed to be common to adipocyte and monocyte/macrophage lines: for example, phagocytic and microbicidal activities, and possibly a cellular plasticity of adipose precursors. Overweight and obesity are associated with an increased risk of such metabolic abnormalities as dyslipidemia, hypertension or type 2 diabetes mellitus and cardiovascular diseases, common features of the metabolic syndrome. Initially, insulin resistance or hyperinsulinemia was suggested as the origin of these abnormalities. More recent studies indicate that adipokynes have an important role in obesity-associated metabolic complications, and suggest that chronically elevated local or systemic concentrations of adipokynes contribute to the development of complications associated with obesity and metabolic syndrome. Considering all the evidence relating to diet and inflammation, the best diet for protecting against the metabolic derangements associated with obesity and metabolic syndrome would be high in fibre-rich cereals, fruit, vegetables, fish, virgin olive oil and nuts; moderate in wine; and low in meat, processed meat foods and trans-fatty acids.
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PMID:Inflammation, obesity and comorbidities: the role of diet. 1790 26

During the last decade, the role of inflammation in the etiopathogenesis of arterial thrombosis has been elucidated. However, little is known about the relationship between inflammation and venous thrombosis. Recently, inflammation has been accepted as a possible mechanism through which different risk factors trigger thrombus formation in veins. The data indicate that inflammation of the vessel wall initiates thrombus formation in an intact vein and that inflammation and coagulation systems are coupled by a common activation pathway. The first event in thrombus formation is most probably activation of endothelial cells, platelets and leucocytes, with initiation of inflammation and formation of microparticles that trigger the coagulation system through the induction of a tissue factor. Therefore, the key event in the initiation of venous thrombus formation is most probably vein wall inflammation. However, expected relationship between inflammatory markers as indicators of inflammatory process and clinical venous thromboembolism (VTE) has not yet been elucidated. C-reactive protein does not appear to be useful in predicting future venous thrombosis or to be useful in the diagnosis of VTE. Recently, it was demonstrated that probable association between VTE and several other markers of inflammation such as: interleukin (IL)-6, IL-8 and tumor necrosis factor-a exists. While these markers of inflammation were studied during or after acute venous thrombosis, further prospective studies are needed to determine the predictive value of inflammatory markers for VTE. The identification and elucidation of inflammatory markers relevant to venous thrombosis could provide targets for future therapy. That inflammation is the basic etiopathogenetic process of VTE is also supported by the relation of some risk factors to both arterial and venous thrombosis: age, increased body mass index, hypercholesterolemia, hypertension, lupus anticoagulant and hyperhomocysteinemia. A relation was also found between preclinical and clinical atherosclerotic disease and VTE. Also in line with these arguments are the preventive effects of aspirin and statins in both arterial and venous disease.
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PMID:The role of inflammation in venous thromboembolism and the link between arterial and venous thrombosis. 1809 97

Management of acute coronary syndromes, particularly unstable angina, acute myocardial infarction and non-Q-wave myocardial infarction, is one of the most common and costly problems facing modern medicine. Furthermore, the increasing availability of new research and clinical information relevant to the treatment of these conditions means that continuing reappraisal of management strategies is necessary. Accordingly, the Ushuaia conference, Tierra Del Fuego, Argentina, was convened to discuss current approaches and future treatment prospects for patients with these conditions. The conference was comprised of leading Argentinian cardiologists whose primary aim was to formulate consensus recommendations regarding the management of patients with acute coronary syndromes. The first of the major recommendations for the pharmacological management of acute coronary syndromes arising from the Ushuaia Consensus Conference was that aspirin (200 to 500mg initially, then 100 to 325 mg/day) should be administered to all patients except those for whom aspirin is absolutely (or relatively, depending on the clinician's discretion) contraindicated. In such cases, ticlopidine is a suitable alternative. Intravenous nitrates are indicated for patients with angina pain (24 to 48 hours' duration), ECG changes, recurrence of angina, or signs of heart failure; in other cases, oral, transdermal or sublingual nitrates may be administered. Use of beta-blockers is recommended except when absolutely contraindicated or when there is a strong suspicion of vasospasm as a dominant mechanism in angina. Intravenous administration of these agents is preferred in patients with tachycardia, arterial hypertension or angina. Calcium antagonists are generally not recommended as first choice therapy, but can be indicated (preferably using agents that decrease heart rate) when beta-blockers are contraindicated or when there is a strong suspicion of vasospasm as a dominant mechanism in angina. Calcium antagonists are also useful in combination with other drugs in patients with high blood pressure or treatment-refractory recurrent angina. Subcutaneous low molecular weight heparins and intravenous unfractionated heparin provide similar results and are indicated in a number of clinical situations. Emergency videocoronary angiography (VCA) is indicated in patients with persistent clinical and haemodynamic instability, recurrent ischaemia with heart failure, and refractory angina. Patients should also be referred for VCA if they have signs of left ventricular dysfunction, post-acute myocardial infarction angina with ECG changes, or ischaemia during functional studies. Post-VCA treatment will be determined by anatomical findings during VCA. Future prospects in the management of acute coronary syndromes include the development of more accurate prognostic markers and means of stratifying risk, such as sophisticated ECG criteria, serum markers of necrosis (e.g. troponin T and I), markers of thrombosis (e.g. D-dimer and fibrinopeptide A levels), markers of inflammation (e.g. reactive protein C, cell adhesion receptor expression, neopterine), and markers of 'good' prognosis (e.g. interleukin-10). Other pharmacological approaches under investigation include platelet IIb/IIIa receptor antagonists, clopidogrel and hirudin. Novel agents, such as anti-Xa, pentasaccharide, anti-tissue factor compounds, Ib receptor-blocking agents, agents that influence vascular endothelium and control cellular acidosis (e.g. HOE 642), macrolide antibiotics, HLA-DR system blockers and fusion compounds, are also in various stages of investigation or development.
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PMID:Current treatment and future prospects for the management of acute coronary syndromes: consensus recommendations of the 1997 ushuaia conference, tierra del fuego, Argentina. 1837 Apr 92

Orthostatic stress causes significant plasma shift and raises transmural pressure in lower extremities, resulting in an increase in endothelial activation and plasma proteins concentrations, possibly including coagulation factors. This may lead to activation of the coagulation system during standing. To test this hypothesis, we recruited 18 healthy volunteers (9 females and 9 males; mean age: 25+/-1.2 years; body mass index: 21.7+/-0.5 kg/m(2)). Hemodynamics, plasma shift (extrapolated from sequential hematocrit concentration), plasma proteins, and coagulation tests, including procoagulants; fibrinogen, factor V, and factor VIII activity; prothrombin fragments 1 and 2; and endothelial activation-related factors (tissue factor and von Willebrand factor), as well as protein C global pathway, were determined at rest supine and at 15 minutes, 30 minutes, and 60 minutes of still standing. Thirty minutes of standing caused a decrease in plasma volume by 12.0+/-0.5% and an increase in plasma protein by 13.0+/-0.7%. Fibrinogen, factor V, and factor VIII activity rose by 12.0+/-1.2%, 13.0+/-1.0%, and 40.0+/-6.0% (P<0.002 for all), respectively. Prothrombin fragments 1 and 2 were elevated by 150.0+/-30.0%. Tissue factor and von Willebrand factor increased by 30.0+/-9.0% and 17.4+/-51.0% (P<0.02 for both), respectively. However, protein C assay results decreased from 0.95+/-0.20 to 0.83+/-0.16 (P<0.001). We hereby introduce a novel physiological mechanism, "orthostatic procoagulation," that should be considered during coagulation tests. Furthermore, it could be extrapolated to the pathophysiology of stasis and venous thromboembolism.
Hypertension 2008 Jun
PMID:Orthostatic hypercoagulability: a novel physiological mechanism to activate the coagulation system. 1841 85


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