Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0012739 (disseminated intravascular coagulation)
 8,673 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A decrease in light transmittance before clot formation, manifesting as a biphasic waveform (BPW) pattern in coagulation assays, was previously correlated with the onset of disseminated intravascular coagulation (DIC). In this study of 1187 consecutive admissions to the intensive care unit, the degree of this change on admission predicts DIC better than D-dimer measurements. Additionally, the BPW preceded the time of DIC diagnosis by 18 hours, on average, in 56% (203 of 362) of DIC patients. The BPW is due to the rapid formation of a precipitate and coincident turbidity change on recalcification of plasma. The isolated precipitate contains very-low-density lipoprotein (VLDL) and C-reactive protein (CRP). The addition of CRP and Ca(++) to normal plasma also causes the precipitation of VLDL and IDL, but not LDL or HDL. The K(d) of the CRP/VLDL interaction is 340 nM, and the IC(50) for Ca(++) is 5.0 mM. In 15 plasmas with the BPW, CRP was highly elevated (77-398 microg/mL), and the concentration of isolated VLDL ranged from 0.082 to 1.32 mM (cholesterol). The turbidity change on recalcification correlates well with the calculated level of the CRP-VLDL complex. Clinically, the BPW better predicts for DIC than either CRP or triglyceride alone. The complex may have pathophysiological implications because CRP can be detected in the VLDL fraction from sera of patients with the BPW, and the VLDL fraction has enhanced prothrombinase surface activity. The complex has been designated lipoprotein complexed C-reactive protein.
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PMID:Biphasic transmittance waveform in the APTT coagulation assay is due to the formation of a Ca(++)-dependent complex of C-reactive protein with very-low-density lipoprotein and is a novel marker of impending disseminated intravascular coagulation. 1223 65

The biphasic waveform that can predict for disseminated intravascular coagulation (DIC) is due to the formation of a calcium-dependent complex between C reactive protein (CRP) and very low density lipoprotein (VLDL). As thrombin generation is pivotal to DIC, this aspect has been specifically investigated and the VLDL component has been found to increase prothrombinase activity via both quantitative and qualitative changes. The specific prothrombinase activity of VLDL from patients manifesting the biphasic waveform was 2.5 times that of normal individuals or critically ill patients without the biphasic waveform. This activity was due to an increase in anionic phospholipid surfaces that could be inhibited with excess annexin V and which was dependent on structurally intact apolipoprotein B. The qualitative change appeared to be due to a deficiency of phosphatidylethanolamine in VLDL from patients with the biphasic waveform. The functional consequence of this enhanced prothrombinase activity was an increased procoagulant effect in plasma. Using a modified activated partial thromboplastin time assay, the mean normal clot time decreased significantly when VLDL from patients with biphasic waveforms was substituted. These results indicate that VLDL derived from patients with the biphasic waveform can enhance thrombin procoagulant activity. As the CRP-VLDL complex exists in vivo, it could have a pathogenic role in disseminating the process of intravascular coagulation.
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PMID:Prothrombinase enhancement through quantitative and qualitative changes affecting very low density lipoprotein in complex with C-reactive protein. 1498 28

A series of benzimidazole derivatives with the side chain on the nitrogen atom oriented to the prime site of factor Xa (FXa) were designed and synthesized. Compounds with substituted aminocarbonylmethyl groups as the side chain showed potent FXa inhibitory activity. Compounds 1 and 2 exhibited most potent inhibitory activity and were effective as anticoagulants in a DIC model.
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PMID:Structure-activity relationships of potent and selective factor Xa inhibitors: benzimidazole derivatives with the side chain oriented to the prime site of factor Xa. 1526 Dec 87

We compared the antithrombotic properties of a factor Xa inhibitor (DX-9065a) with those of a thrombin inhibitor (melagatran) in a rat disseminated intravascular coagulation model and a rat venous thrombosis model. Rat disseminated intravascular coagulation and venous thrombosis models were produced by injection of tissue factor and platinum wire placement, respectively. DX-9065a exerted antithrombotic effects dose dependently in both models. Melagatran was also effective in the venous thrombosis model, whereas it showed an aggravation in the disseminated intravascular coagulation model at low but not high doses. In the in vitro study, DX-9065a decreased the C(max) of the thrombin generation curve in plasma irrespective of whether protein C was present or not. However, melagatran increased the C(max) at low concentrations when protein C was present. This increase was not detected in protein C-deficient plasma. These results suggest that, unlike DX-9065a, melagatran in low doses aggravates disseminated intravascular coagulation by increasing thrombin generation, which may be partly due to suppression of negative feedback by activated protein C.
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PMID:Different antithrombotic properties of factor Xa inhibitor and thrombin inhibitor in rat thrombosis models. 1587 22

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

Serpins maintain haemostasis through regulation of serine proteinases in the thrombotic and thrombolytic pathways. Viruses encode serpins that can alter thrombotic and thrombolytic responses producing, in some cases, disseminated intravascular coagulation (DIC). However, it has not been precisely defined how viral serpins induce these profound responses. The rabbit myxoma viral serpin, Serp-1 inhibits urokinase- and tissue-type plasminogen activators (uPA and tPA), plasmin and factor Xa in vitro and exhibits remarkable anti-inflammatory activity in various animal models. The effects of Serp-1 on activation of human platelets, endothelial cells, monocytes and T cells that mediate thrombosis and innate immune responses were therefore examined. We found that Serp-1 attenuated platelet and mononuclear cell adhesion to fibronectin and collagen. Serp-1 similarly inhibited monocyte migration into the peritoneum. Serp-1 inhibition of monocyte migration was lost in uPA receptor (uPAR) deficient mice. Serp-1 bound to the plasma membrane surface and altered uPA activation of endothelial cells (p=0.001), thrombin activation of platelets (p=0.021) and phorbol ester activation of endothelial (p=0.047), monocyte (p=0.011) and Jurkat T cells (p=0.012) as measured by intracellular calcium. Modulation of cellular activation was confirmed by membrane fluidity analysis. Microarray analysis of Serp-1 treated endothelial cells revealed alterations in Inositol 1,4,5-triphosphate receptor type II (ITPR2) a calcium-regulating gene. This study demonstrates the unique capacity of a viral serpin, Serp-1 to modify adhesion, activation, gene expression and calcium homeostasis in a wide range of cells that regulate coagulation and inflammation. Endothelial cells potentially represent a pivotal regulatory point for Serp-1 anti-inflammatory activity.
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PMID:Myxoma viral serpin, Serp-1, a unique interceptor of coagulation and innate immune pathways. 1652 79

Snake venom induced consumption coagulopathy (VICC) is a common complication of snake bite due to prothrombin activators or thrombin-like enzymes in the venom. This study aimed to determine the efficacy and dose of antivenom for treating VICC in patients envenomed by brown snakes (Pseudonaja spp.), including in vitro coagulation studies. In serial blood samples from patients with brown snake envenoming, venom and antivenom concentrations were measured using enzyme immunoassays. In vitro mixtures of brown snake venom and antivenom were used to investigate antivenom binding, neutralisation of prothrombin activity, prevention of venom-mediated clotting and effect on thrombin generation parameters using a thrombinoscope. In 27 envenomed patients the median venom concentration was 20 ng/mL (Interquartile range[IQR]:12-44 ng/mL) prior to antivenom and was not detected after antivenom administration, including 9 patients given one vial. In vitro, 200 microg/mL of antivenom bound all free venom at venom concentrations seen in patients. In vitro prothrombinase activity of the venom (using a chromogenic substrate) was not neutralised by antivenom. However, for venom concentrations seen in humans, 100 microg/mL of antivenom prevented venom clotting activity in human plasma and 479 microg/mL neutralised procoagulant venom activity measured by triggering thrombin generation. One vial of antivenom appears to be sufficient to bind and neutralise all venom in patients with severe brown snake envenoming.
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PMID:Efficacy of antivenom against the procoagulant effect of Australian brown snake (Pseudonaja sp.) venom: in vivo and in vitro studies. 1705 16

The effect of a serine protease (ASP) secreted from Aeromonas sobria on plasma coagulation was investigated. Proteolytically active ASP promoted human plasma coagulation in a dose-dependent manner. Consistent with the preference for a factor Xa-specific oligo-peptide substrate, ASP produced enzymatic activity from human prothrombin but not from factors IX and X. ASP cleaved prothrombin to produce enzymatically active 37 kDa-fragment displaying the same molecular mass as alpha-thrombin. ASP is the first bacterial serine protease that produces alpha-thrombin, through which ASP may contribute to the induction of thrombotic tendency in disseminated intravascular coagulation complicated with sepsis caused by A. sobria infections.
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PMID:Activation of prothrombin by ASP, a serine protease released from Aeromonas sobria. 1806 62

Amniotic fluid (AF) may induce disseminated intravascular coagulation (DIC) when it enters maternal circulation by breaching the placental-maternal circulation barrier. The precise mechanism of the procoagulant activity of AF is unclear, but tissue factor (TF) has been proposed to be the main cause. As one constituent of AF, AF cells accumulate and undergo apoptosis continuously. Therefore, we speculate that AF cells have procoagulant activity due to the externalisation of phosphatidylserine (PS). The present study aims to demonstrate that, in addition to TF, the PS that is externalised on AF cells is important for the procoagulant activity of AF. Ten AF samples from parturient women were analysed using lactadherin as the probe for PS. Anti-TF antibody also was used to identify TF and its associated coagulation functions in AF cells. Normal platelets, neutrophils, and lymphocytes were harvested as controls. Confocal microscopy and flow cytometry was used to assess PS expression on AF cells. The procoagulant activity of AF cells was demonstrated by a plasma coagulation assay and further confirmed by factor Xase/prothrombinase assays. PS and TF were present on most AF cells, providing substantial procoagulant activity. Furthermore, factor Xase and prothrombinase assays showed that AF cells substantially enforced the activation of factor X and prothrombin. PS on AF cells is an important procoagulant source for AF. Lactadherin is an ideal anticoagulant for inhibiting the procoagulant activity of AF cells.
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PMID:Procoagulant activity and phosphatidylserine of amniotic fluid cells. 1940 26

Recently we prepared sulfated, low-molecular-weight lignins (LMWLs) to mimic the biological activities of heparin and heparan sulfate. Chemo-enzymatically prepared sulfated LMWLs represent a library of diverse non-sugar, aromatic molecules with structures radically different from the heparins, and have been found to potently inhibit thrombin and factor Xa. To assess their effect on the fibrinolytic system, we studied the interaction of LMWLs with human plasmin. Enzyme inhibition studies indicate that the three sulfated LMWLs studied inhibit plasmin with IC50 values in the range of 0.24 and 1.3 mM, which are marginally affected in the presence of antithrombin. Similarly, plasmin degradation of polymeric fibrin is also inhibited by sulfated LMWLs. Michaelis-Menten kinetic studies indicate that maximal velocity of hydrolysis of chromogenic substrates decreases nearly 70% in the presence of LMWLs, while the effect on Michaelis constant is dependent on the nature of the substrate. Competitive binding studies indicate that the sulfated LMWLs compete with full-length heparin. Comparison with thrombin-heparin crystal structure identifies an anionic region on plasmin as a plausible sulfated LMWL binding site. Overall, the chemo-enzymatic origin coupled with coagulation and fibrinolysis inhibition properties of sulfated LMWLs present novel opportunities for designing new pharmaceutical agents that regulate complex pathologies in which both systems are known to play important roles such as disseminated intravascular coagulation.
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PMID:Sulfated, low-molecular-weight lignins are potent inhibitorsof plasmin, in addition to thrombin and factor Xa: Novel opportunity for controlling complex pathologies. 2002


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