Matrix metalloproteinase-10 is upregulated by thrombin in endothelial cells and increased in patients with enhanced thrombin generation

OBJECTIVE: Thrombin is a multifunctional serine protease that promotes vascular proinflammatory responses whose effect on endothelial MMP-10 expression has not previously been evaluated. METHODS AND RESULTS: Thrombin induced endothelial MMP-10 mRNA and protein levels, through a protease-activated receptor-1 (PAR-1)-dependent mechanism, in a dose- and time-dependent manner. This effect was mimicked by a PAR-1 agonist peptide (TRAP-1) and antagonized by an anti-PAR-1 blocking antibody. MMP-10 induction was dependent on extracellular regulated kinase1/2 (ERK1/2) and c-jun N-terminal kinase (JNK) pathways. By serial deletion analysis, site-directed mutagenesis and electrophoretic mobility shift assay an AP-1 site in the proximal region of MMP-10 promoter was found to be critical for thrombin-induced MMP-10 transcriptional activity. Thrombin and TRAP-1 upregulated MMP-10 in murine endothelial cells in culture and in vivo in mouse aorta. This effect of thrombin was not observed in PAR-1-deficient mice. Interestingly, circulating MMP-10 levels (P<0.01) were augmented in patients with endothelial activation associated with high (disseminated intravascular coagulation) and moderate (previous acute myocardial infarction) systemic thrombin generation. CONCLUSIONS: Thrombin induces MMP-10 through a PAR-1-dependent mechanism mediated by ERK1/2, JNK, and AP-1 activation. Endothelial MMP-10 upregulation could be regarded as a new proinflammatory effect of thrombin whose pathological consequences in thrombin-related disorders and plaque stability deserve further investigation

Von Willebrand factor levels predict clinical outcome in patients with cirrhosis and portal hypertension

Background and aims: Endothelial dysfunction is a major determinant of the increased hepatic vascular tone of cirrhotic livers. Von Willebrand factor (vWF), P-selectin and 8-iso-PGF2\u3b1 (isoprostanes), surrogate markers of endothelial dysfunction, are increased in patients with cirrhosis. This study was aimed at exploring in patients with cirrhosis and portal hypertension the relation of these endothelial factors with systemic and hepatic haemodynamics and their possible clinical prognostic value. Methods: 42 consecutive patients with cirrhosis and portal hypertension had measurement of the hepatic venous pressure gradient (HVPG), cardiopulmonary pressures and vWF, P-selectin and isoprostane levels in blood samples from hepatic and peripheral veins. Patients were followed up to 2 years, death or liver transplantation and any clinical event were recorded. Results: vWF, P-selectin and isoprostanes were increased in patients with cirrhosis compared with controls (p<0.001). vWF levels significantly correlated with HVPG, Child-Pugh score and MELD. Cox model analysis disclosed an independent indirect association of peripheral vWF with survival free of portal hypertension-related events and of transplantation. The vWF cut-off value of 216 U/dl (Youden index) disclosed two different populations of patients with cirrhosis with a highly different probability of survival free of portal hypertension-related events and transplantation (87% vs 22%, p=0.001). The prognostic role of vWF persisted after adjusting for parameters of liver dysfunction and for HVPG. Conclusions: In patients with cirrhosis and portal hypertension vWF levels correlate with liver function and HVPG and independently predict clinical outcome

Multicentric evaluation of a new assay for prothrombin fragment F 1+2 determi-nation

A multicenter study of a recently developed ELISA for the determination of prothrombin fragment F1+2 was performed in order to evaluate analytical and clinical aspects. Mean intra-assay and inter-assay reproducibility were found to be 11.0 and 12.6%, respectively. The measuring range covered by the calibration curve reaches from 0.04 to 10.0nM/l F1+2. Testing 133 healthy subjects a reference range of 0.37 to 1.11nM/l F1+2 (2.5-97.5 percentile) with a median of 0.66nM/l F1+2 was calculated. Minor difficulties with blood sampling (venous occlusion for 2 min) did not affect F1+2 plasma concentrations. Significantly increased F1+2 levels were measured in patients with leukemia (p<0.0001), severe liver disease (p<0.005) and after myocardial infarction (p<0.01). Elevated F1+2 concentration before the beginning of heparin therapy (1.25nM/l) decreased to 0.77 nM/l (p<0.0001) after 1 day of therapy. For patients in the stable phase of oral anticoagulant therapy decreasing F1+2 concentrations were measured with increasing INR. F1+2 levels were already significantly reduced in patients with INR <2.0 (0.56nM/l; p=0.0005). Thus F1+2 determination may be helpful in identifying activation processes as well as in monitoring anticoagulant therapy

Patients whose first episode of bleeding occurs while taking a &#946;-blocker have high long-term risks of rebleeding and death

Background & Aims: Patients who have their first episode of variceal bleeding despite primary prophylaxis with a nonselective \u3b2-adrenergic receptor antagonist (also called a nonselective \u3b2-blocker [NSBB]) receive additional treatment by endoscopic band ligation to prevent further bleeding. However, little is known about their long-term outcomes. Methods: We collected data on 89 consecutive patients with cirrhosis who were admitted to the Liver Unit of Hospital Cl\uednic, Barcelona, with acute esophageal variceal bleeding between June 2007 and February 2011. Thirty-four patients were receiving primary prophylaxis with NSBBs when they had their first episode of variceal bleeding, whereas 55 were not receiving NSBBs (controls). All patients were subsequently treated with a combination of endoscopic band ligation and NSBBs. Patients were examined after 1, 3, and 6 months and every 6 months thereafter until 2 years. Results: After 2 years, a greater proportion of patients who had their first episode of bleeding while on NSBBs had further bleeding, compared with controls (48% vs 24%; P = .01). Primary prophylaxis with NSBBs and serum levels of bilirubin were independent predictors of rebleeding. Overall, 11 patients died, and 5 underwent liver transplantation. Liver transplantation-free survival was lower among patients who had their first episode of bleeding while taking NSBBs (66% vs 88% for controls; P = .02). Primary prophylaxis with NSBBs and Child-Pugh class were independently associated with liver transplantation-free survival. Conclusions: Patients who have their first episode of variceal bleeding while on primary prophylaxis with a \u3b2-blocking agent have an increased risk of further bleeding and death, despite adding endoscopic band ligation. These patients possibly require alternative treatment approaches

Metabolomics discloses potential biomarkers to predict the acute HVPG response to propranolol in patients with cirrhosis

Background: In cirrhosis, a decrease in hepatic venous pressure gradient (HVPG)&nbsp;&gt;&nbsp;10% after acute iv propranolol (HVPG response) is associated with a lower risk of decompensation and death. Only a part of patients are HVPG responders and there are no accurate non-invasive markers to identify them. We aimed at discovering metabolomic biomarkers of HVPG responders to propranolol. Methods: Sixty-six patients with cirrhosis and HVPG&nbsp; 65&nbsp;10&nbsp;mm Hg in whom the acute HVPG response to propranolol was assessed, were prospectively included. A targeted metabolomic serum analysis using ultrahigh-performance liquid chromatography coupled to mass spectrometry was performed. Different combinations of 2-3 metabolites identifying HVPG responders (HVPG reduction&nbsp;&gt;&nbsp;10%) were obtained by stepwise logistic regression. The best of these model (AUROC, Akaike criterion) underwent internal cross-validation and cut-offs to classify responders/non-responders was proposed. Results: A total of 41/66 (62%) patients were HVPG responders. Three hundred and eighty-nine metabolites were detected and 177 were finally eligible. Eighteen metabolites were associated to the HVPG response at univariate analysis; at multivariable analysis, a model including a phosphatidylcholine (PC(P-16:0/22:6)) and a free fatty acid (20:2(n-6), eicosadienoic acid) performed well for HVPG response, with an AUROC of 0.801 (0.761 at internal validation). The cut-off 0.629 was the most efficient for overall classification (49/66 patients correctly classified). Two cut-off values allowed identifying responders (0.688, PPV 84%) and non-responders (0.384, NPV 82%) with undetermined values for 17/66 patients. Clinical variables did not add to the model. Conclusions: The combination of two metabolites helps at identifying HVPG responders to acute propranolol. It could be a useful non-invasive test to classify the HVPG response to propranolol

Análise genética da habilidade de permanência em fêmeas da raça Nelore Genetic analysis of stayability among Nelore females

O objetivo deste estudo foi verificar a possibilidade da característica habilidade de permanência (HP) de matrizes ser utilizada como critério de seleção na raça Nelore. A HP foi definida como a probabilidade de uma vaca parir, no rebanho, na idade de seis anos ou depois desta idade, dado que ela teve uma parição em data anterior. Foram analisadas informações de 55.682 animais. Utilizou-se a amostragem de Gibbs para estimar os componentes de variância e um modelo de limiar de máximo a posteriori para predizer os valores genéticos. A análise forneceu estimativa posterior de herdabilidade e desvio-padrão de 0,21 &plusmn; 0,00 e tendência genética, média por ano, de 0,14% para HP. A facilidade de mensuração da característica, a estimativa de herdabilidade e a tendência indicam que a utilização desta característica como critério de seleção pode contribuir para o aumento da fertilidade do rebanho.<br>The purpose of this study was to analyse of the stayability trait (STAY) of Nelore cows. Stayability was defined as the probability of calving at a specific age, or after that age, given that the cow calved at least one time prior to that age. The study focused specifically on six year old groups, and the information corresponding to 55,682 animals were analysed. The data were analysed based on an a posteriori maximum threshold model to predict the genetic values, while the Gibbs sample was used to estimate the variance components. The analyses provided heritability estimate and standard deviation of 0.21 &plusmn; 0.003 and average genetic tendency a year was of 0.14% for STAY. The estimates indicate that the use of this trait as a criterion for selection may contribute toward increased female fertility