Tissue-type Plasminogen Activator Antigen Research Articles

CEREBRAL AND SYSTEMIC ENDOTHELIAL DYSFUNCTION IN MIGRAINE: CURRENT KNOWLEDGE AND PERSPECTIVE

Migraine still causes a high rate of disability and is reported to increase the risk of cardiovascular and cerebrovascular diseases. Endothelial dysfunction is considered to be one of the underlying mechanisms linking migraine and vascular disorders. Investigation of endothelial function in migraine includes a variety of examinations including biomarkers and ultrasonography-based studies. Several proposed biomarkers for endothelial dysfunction are endothelial progenitor cells (EPCs), von Willebrand factor (vWF), nitric oxide (NO), tissue-type plasminogen activator antigen (tPA antigen), C-reactive protein (CRP), endothelin-1 (ET-1), and vascular endothelial growth factor (VEGF). Brachial flow-mediated dilatation (FMD) is quite commonly used to reflect systemic endothelial dysfunction, while cerebral endothelial function can be assessed using breath holding index (BHI) on transcranial Doppler (TCD). The results of most studies in migraine sufferers indicate that endothelial dysfunction is found locally in the cerebral circulation, especially at the posterior circulation, while evidence for endothelial dysfunction in the systemic circulation remains controversial.

Association of NT-proBNP and GDF-15 with markers of a prothrombotic state in patients with atrial fibrillation off anticoagulation

We investigated whether growth differentiation factor-15 (GDF-15), also known as macrophage inhibitory cytokine-1 (MIC-1), levels are associated with a prothrombotic state in atrial fibrillation (AF) as compared to N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin I (cTnI-hs). In 103 patients with AF assessed off anticoagulation (age: 71.0 [65.0–76.0] years; CHA2DS2-VASc score: 4.6 ± 1.7), we measured endogenous thrombin potential (ETP), plasma fibrin clot permeability (Ks, a measure of clot density) and clot lysis time (CLT) and other hemostatic parameters, along with GDF-15, NT-proBNP, and cTnI-hs. GDF-15 positively correlated with ETP and CLT (r = 0.25, P = 0.01 and R = 0.56, P < 0.0001, respectively) but not with Ks, von Willebrand factor, thrombin-activatable fibrinolysis inhibitor, plasminogen, antiplasmin or tissue-type plasminogen activator antigen. NT-proBNP showed a stronger association with ETP (r = 0.60, P < 0.0001) and a similar correlation with CLT (R = 0.53, P < 0.0001), while cTnI-hs correlated solely with CLT (R = 0.25, P = 0.01). After adjustment for clinical and laboratory parameters, GDF-15 was a better independent predictor of CLT (unstandardized coefficient B 0.009; 95% confidence interval [CI] 0.006–0.012) than NT-proBNP (B 0.007; 95% CI 0.004–0.010, R (2) = 0.51; P < 0.0001); while among the three biomarkers, only NT-proBNP was an independent predictor of ETP. Elevated GDF-15 and NT-proBNP independently predict impaired fibrin clot lysability, while NT-proBNP is a key predictor of heightened thrombin formation in AF. Our findings suggest that a predictive value of NT-proBNP and GDF-15 in AF could be in part attributed to their association with prothrombotic blood alterations.Graphic

Effect of spironolactone for 1 yr on endothelial function and vascular inflammation biomarkers in renal transplant recipients.

Kidney transplantation is associated with increased cardiovascular risk. Endothelial dysfunction and vascular inflammation contribute to negative outcome. In experimental models, mineralocorticoid receptor antagonists improved endothelial function and reduced inflammation. The present study tested the hypothesis that the mineralocorticoid receptor antagonist spironolactone improves endothelial function and reduces vascular inflammation in renal transplant patients. Eighty prevalent renal transplant patients from an ongoing, double-blind randomized placebo-controlled trial were included. Paired plasma samples before and after 1 yr of treatment (n = 39 in the spironolactone-treated group and 41 in the placebo-treated group) were used to determine markers of endothelial dysfunction (nitrite, nitrate, cGMP, arginine, citrulline, ornithine, asymmetric dimethylarginine, symmetric dimethylarginine, NG-monomethyl-l-arginine, von Willebrand factor, tissue-type plasminogen activator antigen, and plasminogen activator inhibitor 1 antigen) and markers of inflammation (intercellular adhesion molecule, vascular adhesion molecule, high-sensitivity C-reactive protein, and serum amyloid protein A). The median time since the transplantation was 4.6 (0.12-22.3) yr in the spironolactone-treated group and 2.1 (0.17-13.9) yr in the placebo-treated group (P > 0.05). Spironolactone increased plasma aldosterone (P < 0.001) and K+ (P < 0.001). Blood pressure did not change significantly. No significant differences were detected between groups in any of the measured markers of endothelial dysfunction or inflammation except in the subgroup analysis of patients with diabetes, where spironolactone decreased nitrite compared with placebo. In this study, mineralocorticoid receptor antagonism did not improve biomarkers of endothelial dysfunction or vascular inflammation in prevalent renal transplant patients. Further studies are needed to evaluate the potential beneficial effect of early or late mineralocorticoid receptor antagonism on vascular outcomes in renal transplant patients.

Increased Fibrinolysis as a Specific Marker of Poor Outcome After Cardiac Arrest.

Recent data suggest that early increased fibrinolysis may be associated with unfavorable prognosis in cardiac arrest. The current study aimed to assess whether there is an optimal fibrinolysis cutoff value as determined by thrombelastometry at hospital admission to predict poor outcome in a cohort of adult patients with out-of-hospital cardiac arrest. Prospective observational cohort study. Emergency department of a 2.100-bed tertiary care facility in Vienna, Austria, Europe. Patients with out-of-hospital cardiac arrest of presumed cardiac origin, subjected to targeted temperature management, who had achieved return of spontaneous circulation at admission were analyzed. None. Fibrinolysis was assessed by thrombelastometry at the bedside immediately after hospital admission and is given as maximum lysis (%). The outcome measure was the optimal cutoff for maximum lysis at hospital admission to predict poor outcome (a composite of Cerebral Performance Category 3-5 or death) at day 30, assessed by receiver operating characteristic curve analysis. Seventy-eight patients (61% male, median 59 yr) were included in the study from March 2014 to March 2017. Forty-two patients (54%) had a poor 30-day outcome including 23 nonsurvivors (30%). The maximum lysis cutoff at admission predicting poor 30-day outcome with 100% specificity (95% CI, 90-100%) was greater than or equal to 20%. Tissue-type plasminogen activator antigen levels were likewise elevated in patients with poor neurologic outcome or death 52 ng/mL (interquartile range, 26-79 ng/mL) versus 29 ng/mL (interquartile range, 17-49 ng/mL; p = 0.036). Increased fibrinolysis at admission assessed by thrombelastometry specifically predicts poor outcome in cardiac arrest with presumed cardiac etiology.

Effects of gastric bypass surgery followed by supervised physical training on inflammation and endothelial function: A randomized controlled trial

Background and aimsObesity and physical inactivity are both associated with low-grade inflammation and endothelial dysfunction. Bariatric surgery improves markers of inflammation and endothelial function, but it is unknown if physical training after bariatric surgery can improve these markers even further. Therefore, we aimed to investigate the effects of Roux-en-Y gastric bypass (RYGB) followed by physical training on markers of low-grade inflammation and endothelial function. MethodsSixty patients approved for RYGB underwent examinations pre-surgery, 6, 12, and 24 months post-surgery. Six months post-surgery, they were randomized 1:1 to an intervention group or a control group. The interventions consisted of two weekly sessions of supervised moderate intensity physical training for a period of 26 weeks. Fasting blood samples were analyzed for concentrations of interleukin 6 (IL-6), C-reactive protein (CRP), intercellular adhesion molecule 1 (ICAM-1), tissue-type plasminogen activator antigen (t-PA:Ag) and von Willebrand factor (vWF). ResultsRYGB markedly improved markers of inflammation (IL-6, CRP) (p < 0.001) and endothelial function (ICAM-1, t-PA:Ag, vWF) (p < 0.05), and the improvements were sustained 24 months post-surgery (p < 0.01), except for the effects on vWF. We found no correlations between the changes in weight or BMI and the changes in markers of inflammation and endothelial function, except that the change in vWF was found to be inversely correlated with the changes in weight and BMI. We observed no effects of supervised physical training on markers on inflammation or endothelial function (p>0.1 for all). ConclusionsRYGB causes substantial and sustained favorable effects on markers of inflammation and endothelial function. Supervised physical training after RYGB did not cause additional improvements.

Colistin dampens fibrinolysis and endothelial activation during endotoxaemia

SummaryColistin electrostatically interacts with lipopolysaccharides (LPS). Preclinical studies demonstrated beneficial effects of colistin on LPS-induced coagulation and fibrinolysis. The objective of this trial was to investigate the effects of colistin during experimental endotoxaemia. In this randomised, double-blind, placebo-controlled, crossover trial 16 healthy volunteers received a 2 ng/kg LPS bolus after infusion of 2.5 million IU colistin or placebo. Plasma levels of F1+2 prothrombin fragments, thrombin-antithrombin complexes (TAT), von Willebrand factor antigen levels (vWF), E-selectin, plasmin-antiplasmin complexes (PAP), tissue-type plasminogen activator (t-PA) antigen and activity, plasminogen activator inhibitor-1 (PAI-1) were measured. Infusion of colistin significantly reduced peak concentrations of PAP complexes by 70 %, t-PA antigen levels by 63 % and t-PA activity by 48 %, while PAI-1 levels decreased numerically by 63 %. Two hours after the LPS bolus F1+2 levels and TAT complexes were slightly reduced in the colistin period, but peak concentrations were similar in both periods. Colistin blunted the LPS induced four-fold increase in soluble E-Selectin levels by ∼50 % and the two-fold increase in vWF antigen levels by ∼70 %. The LPS-scavenging actions of colistin significantly reduce endothelial activation and fibrinolytic response in the human endotoxaemia model, while the activation of the coagulation system remains largely unaffected.Note: This work was conducted at the Medical University of Vienna.EudraCT-Nr.: 2014–00285720 Supplementary Material to this article is available online at http://www.thrombosis-online.com

Impact of carbon monoxide and nitrogen dioxide on cardiovascular biomarkers in the Study of Women's Health Across the Nation

Introduction: Impacts from ambient carbon monoxide (CO) and nitrogen dioxide (NO2) on cardiovascular disease (CVD) has been reported, but the biologic mechanisms connecting them remain uncertain. This study examined whether elevated ambient CO and NO2 levels related to levels of CVD markers in midlife women. Methods: Annual repeated measurements of ten CVD markers, including high-sensitivity C-reactive protein (hs-CRP), fibrinogen, Factor VIIc, tissue-type plasminogen activator antigen (tPA-ag), plasminogen activator inhibitor Type 1 (PAI-1), and lipoprotein markers, were obtained from 2,207 women from five racial/ethnic groups enrolled in 6 US cities for the longitudinal Study of Women’s Health Across the Nation (average 3.8 visits/woman, mean age: 51±3 years). CO and NO2 data were obtained from the USEPA and assigned to each woman based on proximity to her home address. Prior year, 6-month, 30-day, 7-day, and one-day exposures were calculated, and their associations with CVD markers were examined using longitudinal mixed-effects models. Results: Adjusting for site, race/ethnicity, education, menopause status, body mass index, smoking, and recent alcohol use, CO and NO2 exposures were positively associated with fibrinogen, PAI-1, and tPA-ag levels. For an interquartile increase of the 1-year average gas concentration, 0.68 ppm for CO and 13 ppb for NO2, PAI-1 level increased 35% (95% CI: 29%, 42%) and 71% (57%, 86%), respectively. The same increases in the 30-day average CO and NO2 concentration corresponded to 4.5% (2.6%, 6.5%) and 4.5% (2.0%, 7.0%) increases in fibrinogen level. Adjusting for long-term PM2.5 exposure, the impact of 1-year CO exposure on PAI-1 was reduced to 18% (12%, 25%), and the association between CO and tPA-ag was null, indicating that PM2.5 also contributed to variations in these CVD markers. Conclusions: CO and NO2 exposures may increase coagulation and thrombotic potential, and thus may increase risks of CVD in midlife women.

THE RELATION BETWEEN FIBRINOLYTIC SYSTEM AND THE RENIN ANGIOTENSIN SYSTEM

Several lines of evidence point to an interrelation of the renin-angiotensin system (RAS) with the endogenous fibrinolytic system. This study was planned to examine the effect of salt depletion as a method of activation of the endogenous RAS on plasma fibrinolytic balance in 10 healthy human subjects in the presence and absence of angiotensin converting enzyme inhibitor-ACEi (captopril). Activation of the RAS during low salt intake was documented by a significant increase in serum aldosterone concentration. The data suggest that activation of the RAS results in increased plasminogen activator inhibitors (PAI-I) antigen and that interruption of the RAS with the ACE inhibitor captopril significantly lowers PAI-I antigen without lowering tissue-type plasminogen activator (t-PA) antigen. In conclusion, this study provides an evidence of a direct functional link between the RAS and the fibrinolytic system in humans and these findings may help to elucidate possible mechanisms by which ACE inhibition exerts vasculo protective effects and reduces the risk of atherothrombotic events.

Determinants of hypofibrinolysis in patients with digestive tract cancer.

IntroductionRecently, we demonstrated that digestive tract cancer (DTC) is associated with reduced fibrin clot permeability and impaired fibrinolysis.AimWe investigated determinants of fibrinolysis in DTC patients.Material and methodsIn 44 consecutive patients with DTC and 47 controls matched for age, sex, and cardiovascular risk, we evaluated fibrinolysis proteins, platelet activation markers, thrombin formation, together with plasma clot lysis time assays in the absence (CLT) and presence of carboxypeptidase potato inhibitor (CLT CPI) that blocks thrombin activatable fibrinolysis inhibitor (TAFI).ResultsIn the DTC group CLT (by 22.3%) and CLT CPI (by 27.4%) were longer compared with controls. The DTC patients had higher plasma fibrinolysis inhibitors, plasminogen activator inhibitor 1 (PAI-1) (by 18.2%), TAFI activity (by 17.3%), and antigen (by 11.2%). The patients had markedly increased platelet markers – soluble CD40 ligand (by 338%) and P-selectin (by 97%), together with von Willebrand factor (vWF) antigen (by 61%). Thrombin-antithrombin complexes (TAT) (by 48.7%) and soluble thrombomodulin (sTM) (by 17.2%) were also increased in the DTC group (all p < 0.05). Patients with high-grade tumours (n = 26) compared with remainders (n = 18) had longer CLT, higher tissue-type plasminogen activator antigen, both TAFI antigen and activity levels, vWF, and sTM. Multiple regression analysis after adjustment for potential confounders showed that independent predictors of CLT in DTC patients were TAT, TAFI activity, and vWF. The only independent predictor of CLT CPI was TAT.ConclusionsHypofibrinolysis in DTC patients is largely driven by enhanced thrombin generation, TAFI, and endothelial injury.

Long- and Short-term Exposure to Air Pollution and Inflammatory/Hemostatic Markers in Midlife Women.

Studies have reported associations between long-term air pollution exposures and cardiovascular mortality. The biological mechanisms connecting them remain uncertain. We examined associations of fine particles (PM2.5) and ozone with serum markers of cardiovascular disease risk in a cohort of midlife women. We obtained information from women enrolled at six sites in the multi-ethnic, longitudinal Study of Women's Health Across the Nation, including repeated measurements of high-sensitivity C-reactive protein, fibrinogen, tissue-type plasminogen activator antigen, plasminogen activator inhibitor type 1, and factor VIIc (factor VII coagulant activity). We obtained residence-proximate PM2.5 and ozone monitoring data for a maximum five annual visits, calculating prior year, 6-month, 1-month, and 1-day exposures and their relations to serum markers using longitudinal mixed models. For the 2,086 women studied from 1999 to 2004, PM2.5 exposures were associated with all blood markers except factor VIIc after adjusting for age, race/ethnicity, education, site, body mass index, smoking, and recent alcohol use. Adjusted associations were strongest for prior year exposures for high-sensitivity C-reactive protein (21% increase per 10 μg/m³ PM2.5, 95% confidence interval [CI]: 6.6, 37), tissue-type plasminogen activator antigen (8.6%, 95% CI: 1.8, 16), and plasminogen activator inhibitor (35%, 95% CI: 19, 53). An association was also observed between year prior ozone exposure and factor VIIc (5.7% increase per 10 ppb ozone, 95% CI: 2.9, 8.5). Our findings suggest that prior year exposures to PM2.5 and ozone are associated with adverse effects on inflammatory and hemostatic pathways for cardiovascular outcomes in midlife women.

Estimating the Effects of Long-Term Exposure to Air Pollution on Inflammatory/Hemostatic Markers. Findings from the SWAN Study

Estimating the Effects of Long-Term Exposure to Air Pollution on Inflammatory/Hemostatic Markers. Findings from the SWAN StudyAbstract Number:2038 Rochelle Green*, Rachel Broadwin, Brian Malig, Rupa Basu, Ellen Gold, Lihong Qi, Joyce Bromberger, Gail Greendale, Howard Kravitz, Kristin Tomey, Karen Matthews, Carol Derby, Elizabeth Jackson, Robin Green, and Bart Ostro Rochelle Green* Office of Environmental Health Hazard Assessment, United States, E-mail Address: [email protected] Search for more papers by this author , Rachel Broadwin Office of Environmental Health Hazard Assessment, United States, E-mail Address: [email protected] Search for more papers by this author , Brian Malig Office of Environmental Health Hazard Assessment, United States, E-mail Address: [email protected] Search for more papers by this author , Rupa Basu Office of Environmental Health Hazard Assessment, United States, E-mail Address: [email protected] Search for more papers by this author , Ellen Gold Department of Public Health Sciences, University of California Davis School of Medicine, United States, E-mail Address: [email protected] Search for more papers by this author , Lihong Qi Department of Public Health Sciences, University of California Davis School of Medicine, United States, E-mail Address: [email protected] Search for more papers by this author , Joyce Bromberger Department of Psychiatry, University of Pittsburgh School of Medicine, United States, E-mail Address: [email protected] Search for more papers by this author , Gail Greendale Department of Medicine, David Geffen School of Medicine, University of California-Los Angeles, United States, E-mail Address: [email protected] Search for more papers by this author , Howard Kravitz Rush University Medical Center, United States, E-mail Address: [email protected] Search for more papers by this author , Kristin Tomey School of Public Health, University of Michigan, United States, E-mail Address: [email protected] Search for more papers by this author , Karen Matthews Department of Psychiatry, University of Pittsburgh School of Medicine, United States, E-mail Address: [email protected] Search for more papers by this author , Carol Derby Albert Einstein College of Medicine, United States, E-mail Address: [email protected] Search for more papers by this author , Elizabeth Jackson Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan Hospital and Health Systems, United States, E-mail Address: [email protected] Search for more papers by this author , Robin Green Albert Einstein College of Medicine, United States, E-mail Address: [email protected] Search for more papers by this author , and Bart Ostro Office of Environmental Health Hazard Assessment, United States, E-mail Address: [email protected] Search for more papers by this author AbstractBackground: Several studies have reported associations between long-term air pollution exposures and cardiovascular mortality. The biological mechanisms connecting them remain uncertain.Objectives: Examine effects of fine particles (PM2.5) and ozone on serum markers of cardiovascular disease (CVD) risk in a cohort of midlife women.Methods: We obtained information from women enrolled at six sites in the multi-ethnic, longitudinal Study of Women’s Health Across the Nation, including repeated measurements of high-sensitivity C-reactive protein (hs-CRP), fibrinogen, tissue-type plasminogen activator antigen (tPA-ag), plasminogen activator inhibitor Type 1 (PAI-1), and Factor VIIc. We obtained residence-proximate PM2.5 and ozone monitoring data for a maximum five annual visits, calculating prior year, six-month, one-month, and one-day exposures and their relations to serum markers using longitudinal mixed models.Results: For the 2,086 women studied, after adjusting for age, race/ethnicity, site, body mass index, smoking and recent alcohol use, PM2.5 exposures were significantly associated with all blood markers except Factor VIIc. Adjusted associations were of the highest magnitude for year-prior exposures for hs-CRP (20.88% increase per 10 µg/m3 PM2.5, 95% CI: 6.59, 37.10), tPA-ag (8.61%, 95% CI: 1.82, 15.86), and PAI-1 (34.64%, 95% CI: 18.70, 52.72). Findings did not change significantly after further adjustment for health and other lifestyle characteristics. A significant association was also observed between year prior ozone exposure and Factor V11C (5.67% increase per 10 ppb ozone, 95% CI: 2.90 , 8.53).Conclusions: Our findings suggest that prior year exposures to PM2.5 and ozone adversely affect inflammatory and hemostatic pathways for cardiovascular outcomes in midlife women.

Extracellular histones mediate the effects of metal-rich air particles on blood coagulation

BackgroundEpidemiological studies have shown associations of particulate matter (PM) exposure with hypercoagulability and thrombosis. Extracellular circulating histones have recently been identified as novel mediators of inflammatory and procoagulant responses. The potential roles of extracellular histones in PM-related hypercoagulability have yet not been investigated. ObjectivesIn 63 steel workers, we evaluated the effects of exposure to PM and PM metal components on two extracellular histone modifications (H3K4me3 and H3K9ac); and the association of H3K4me3 and H3K9ac with coagulation markers. MethodsExtracellular H3K4me3 and H3K9ac were determined in plasma through enzyme-linked immunosorbent assays. Coagulation markers included endogenous thrombin potentials (ETPs), tissue-type plasminogen activator antigen (t-PA) and d-dimer. Exposure to PM with aerodynamic diameters <1μm (PM1) or <10μm (PM10) and PM10 metal components were estimated for each participant. ResultsThe coagulation marker ETP, measured in the presence of soluble thrombomodulin (ETP TM+), showed significant positive associations with PM1 (β=107.84, p=0.03), PM10 (β=83.06, p=0.02), and zinc (β=75.14, p=0.03); and a marginal association with iron (β=122.58, p=0.07). Additional PM effects were observed on t-PA, D-dimer, and ETP TM+. PM1 exposure was associated with increased plasma H3K4me3 and H3K9ac (β=0.20, p=0.02; β=0.16, p=0.05, respectively). H3K4me3, but not H3K9ac, was associated with zinc (β=0.13, p=0.03) and iron (β=0.32, p=0.01) contained in PM. ETP TM+ was increased in association with higher plasma H3K4me3 (β=0.50, p=0.05) and H3K9ac (β=0.54, p=0.05). ConclusionsThis observational study suggests potential roles of extracellular histones in PM-induced hypercoagulability. Experimental studies are warranted to further characterize these findings.

Markers of Thrombogenesis and Fibrinolysis and Their Relation to Inflammation and Endothelial Activation in Patients with Idiopathic Pulmonary Arterial Hypertension

BackgroundChronic anticoagulation is a standard of care in idiopathic pulmonary arterial hypertension (IPAH). However, hemostatic abnormalities in this disease remain poorly understood. Therefore, we aimed to study markers of thrombogenesis and fibrinolysis in patients with IPAH.MethodsWe studied 27 consecutive patients (67% female) with IPAH aged 50.0 years (IQR: 41.0 - 65.0) and 16 controls without pulmonary hypertension. Prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin (TAT) complexes were measured to assess thrombogenesis; tissue-type plasminogen activator (tPA) antigen and plasmin-anti-plasmin complex to characterize activation of fibrinolysis; plasminogen activator inhibitor 1 (PAI-1) to measure inhibition of fibrinolysis; and endothelin-1 (ET-1) and interleukin-6 (IL-6) to assess endothelial activation and systemic inflammation, respectively. In addition, in treatment-naive IPAH patients these markers were assessed after 3 months of PAH-specific therapies.ResultsTPA (10.1[6.8-15.8] vs 5.2[3.3-7.3] ng/ml, p<0.001), plasmin-anti-plasmin (91.5[60.3-94.2] vs 55.8[51.1-64.9] ng/ml, p<0.001), IL-6 (4.9[2.5-7.9] vs 2.1[1.3-3.8] pg/ml, p=0.001) and ET-1 (3.7 [3.3-4.5] vs 3.4[3.1-3.5], p= 0.03) were higher in patients with IPAH than in controls. In IPAH patients plasmin-anti-plasmin and tPA correlated positively with IL-6 (r=0.39, p=0.04 and r=0.63, p<0.001, respectively) and ET-1 (r=0.55, p=0.003 and r=0.59, p=0.001, respectively). No correlation was found between tPA or plasmin-anti-plasmin and markers of thrombogenesis. Plasmin-anti-plasmin decreased after 3 months of PAH specific therapy while the other markers remained unchanged.ConclusionsIn the present study we showed that markers of fibrynolysis were elevated in patients with IPAH however we did not find a clear evidence for increased thrombogenesis in this group of patients. Fibrinolysis, inflammation, and endothelial activation were closely interrelated in IPAH.

Short-term alcohol consumption may have detrimental effect on fibrinolysis and endothelial function: preliminary report of prospective randomised study

This study was designed to clarify the impact of the short-term consumption of different types of alcoholic beverages on haemostatic factors, C-reactive protein (hsCRP) and endothelin-1 (E-1) plasma levels. The study group consisted of 57 healthy male volunteers, aged 20-29 years. Subjects were randomised to consume 300 mL of red wine, white wine, 12% ethanol, black currant juice or water for five days. Blood samples were collected for CRP, tissue type plasminogen activator antigen (t-PA:Ag), plasminogen activator inhibitor antigen (PAI-1:Ag) and E-1 at baseline, on day 2, and on day 6. A significant increase in PAI-1:Ag concentration was observed in the red wine drinking group (day 1: 44.98; day 2:56.86; day 6: 47.44 ng/mL; p = 0.05). A similar increase of E-1 level was found in the 12% ethanol group (day 1: 0.53; day 2:1.65; day 6: 1.11 fmol/mL; p = 0.01). Dividing the whole study group according to ethanol content of consumed beverages revealed significant changes in tPA:Ag, PAI-1:Ag and E-1 levels. In the alcohol drinking group, significant increases of PAI-1:Ag (day 1: 44.75; day 2: 54.07; day 6: 44.80 ng/mL; p < 0.05); tPA:Ag level (day 1: 3.65; day 2: 4.17; day 6: 5.03 ng/mL;p < 0.02) and E-1 (day 1: 0.42; day 2: 1.01; day 6: 0.97 fmol/mL; p < 0.002) were observed. Short-term alcohol consumption increases tPA:Ag, PAI:Ag and E-1 plasma levels. This effect may have an unfavourable impact on the fibrinolytic system and endothelial function.

The role of hypovitaminosis D in pregnancy-related venous thromboembolism

To the Editor: Venous thromboembolism (VTE) is a leading cause of maternal morbidity and mortality during pregnancy (1). Strategies of pharmacological thromboprophylaxis are based on balancing the perceived risk of thrombosis with the adverse effects of thromboprophylaxis. We propose that an important risk factor for VTE, which is easily overlooked, and which needs to be checked in this setting is hypovitaminosis D. Mounting evidence has shown a high prevalence of vitamin D deficiency during pregnancy (2). Hypovitaminosis D during pregnancy not only is linked to maternal skeletal preservation and fetal skeletal formation, but is also vital to the fetal ‘imprinting’ that may affect chronic disease susceptibility later in life as well as soon after birth (3, 4). On the other hand, it has been found that active sun exposure lowers the risk of thrombotic events (5), thus suggesting that variation in vitamin D status, strictly related to sun exposure, might be a plausible cause for the seasonal variation in thromboembolic complications. 1,25-dihydroxyvitamin [1,25(OH)2D], the active form of the vitamin D, has been shown to have anticoagulant properties by upregulating thrombomodulin and downregulating tissue factor (6). Furthermore, levels of 25-hydroxyvitamin D [25(OH)D], the measurable form of vitamin D, which better represents vitamin D status, have been shown to be inversely related to plasminogen activator inhibitor 1 and tissue-type plasminogen activator antigen levels (7), thus indicating that vitamin D is related to fibrinolytic activity and to the integrity of the vascular endothelium. Interestingly, a randomised controlled study of 250 patients with prostate cancer, half of whom were given 45 micrograms of 1,25(OH)2D weekly, found an unexpected significantly lower risk of thrombotic events (2 vs. 11) (8). On the basis of this evidence, it seems worthwhile to recommend to pregnant women that they supplement with vitamin D for global health benefits, and for VTE prevention in particular. A randomised controlled trial of vitamin D during pregnancy and lactation found that 4000 IU/d vitamin D3 was required for pregnant women to have sufficient 25(OH)D to control gene expression during fetal development and for nursing women to have sufficient unconverted vitamin D3 in their milk so the nursing infant can produce its own 25(OH)D (9). In addition, no adverse effects of this supplementation was found. In particular, there was no change in urine or serum calcium (9). It was therefore recommended that circulating 25(OH)D be 40–60 ng/ml (100–150 nmol/l) during pregnancy, and that a daily intake of 4000 IU vitamin D3 is required to attain that circulating concentration (10). Therefore, hypovitaminosis D should represent a potentially modifiable risk factor to be targeted at the beginning and during pregnancy, also to prevent thromboembolic complications. W.B.G. receives funding from the UV Foundation (McLean, VA), Bio-Tech Pharmacal (Fayetteville, AR), the Vitamin D Council (San Luis Obispo, CA), and the Vitamin D Society (Canada).

Extracellular histones affect blood coagulation in subjects exposed to metal-rich air particles

ObjectivesEpidemiological findings suggest an association between particulate matter (PM) exposure and hypercoagulability and thrombosis. The underlying mechanism for PM-related procoagulative effects is still unknown, but recently, elevated levels of extracellular...

Anticoagulant and Fibrinolytic Disorders in Patients with Behçet's Disease and Recurrent Aphthous Ulcer

Behçet's disease (BD) is a chronic multisystemic inflammatory disorder characterized by recurrent oral and genital aphthous ulcers, uveitis and skin lesions. Recurrent aphthous ulcer (RAU) is the most prevalent oral mucosal disease in humans. The pathogenesis and thrombopoiesis of BD and RAU have not been fully clarified. To reveal the haemostatic dysfunctions in the patients with BD and RAU, we evaluated the levels of coagulant, anticoagulant and fibrinolytic parameters in these patients.Factor VIII clotting activity (FVIII:c), protein C antigen (PC:Ag), total protein S antigen (TPS: Ag), tissue-type plasminogen activator antigen (t-PA:Ag), plasminogen activator inhibitor-1 antigen (PAI-1:Ag) and D-dimer were detected in 24 BD, 58 RAU patients and 50 controls. Results showed that levels of PC:Ag, TPS:Ag, PAI-1:Ag and D-dimer were significantly elevated in both BD and RAU patients compared with controls (P<0.01). PAI-1:Ag was even higher in BD patients than in RAU patients (74.99±12.28 vs. 69.57±13.11, P<0.05), whereas the level of t-PA:Ag was significantly reduced in patients with BD and RAU (P<0.01). In patients with RAU, PC:Ag was lower in major aphthous ulcer (MjAU) group than in minor aphthous ulcer (MiAU) group (P<0.05). The expression of FVIII:c was significantly elevated in MiAU patients compared with controls (P<0.01), while no difference was observed between MjAU patients and controls (P>0.05). Our studies showed that there were anticoagulant and fibrinolytic disorders in BD patients, which may be responsible for diminished fibrinolysis in BD. Some haemostatic parameters may be correlated with the severity of RAU.

Ancrod and Fibrin Formation

Ancrod, derived from Malayan pit viper venom, has been tested as ischemic stroke treatment in clinical trials with inconsistent results. We studied the actions of ancrod on fibrinolysis pathways in patient plasma samples and endothelial cell culture systems. We analyzed fibrinogen levels during the first 6 hours of ancrod infusion in patients entered in the Stroke Treatment with Ancrod Trial. For the in vitro study, human brain microvascular endothelial cells incubated with plasminogen or with human brain microvascular endothelial cell-conditioned medium were co-incubated with ancrod and fibrinogen under normal or oxygen-glucose deprivation conditions over 6 hours. Fibrinogen levels decreased both in vivo and in vitro. Ancrod generated fibrinopeptide A, caused visible clot formation, and reduced levels of tissue-type plasminogen activator antigen in the human brain microvascular endothelial cell system and in a cell-free system with conditioned media. The in vitro results indicate that ancrod causes local fibrin formation and secondary depletion of tissue-type plasminogen activator by binding to fibrin clot. Ancrod-induced fibrin formation could result in cerebral microvascular occlusion and may explain the suboptimal clinical effects of ancrod in human stroke trials.

THE RELATION BETWEEN THE RENIN-ANGIOTENSIN SYSTEM AND FIBRINOLYTIC SYSTEM

Background: Several lines of evidence point to an interrelation of the renin angiotensin system (RAS) with the endogenous fibrinolytic system. Aim & Methods: this study was planned to examine the effect of salt depletion as a method of activation of the endogenous RAS on plasma fibrinolytic balance in 10 healthy human subjects in the presence and absence of Angiotensin converting enzyme inhibitor- ACEi (captopril). Activation of the RAS during low salt intake was documented by a significant increase in serum aldosterone concentration. Results: the data suggest that activation of the RAS results in increased plasminogen activator inhibitors (PAI-I) antigen and that interruption of the RAS with the ACE inhibitor captopril significantly lowers PAI-I antigen without lowering tissue-type plasminogen activator (t-PA) antigen. Conclusion: this data provides an evidence of a direct functional link between the RAS and the fibrinolytic system in humans and these findings may help to elucidate possible mechanisms by which ACE inhibitionexerts vasculoprotective effects and reduces the risk of atherothrombotic events.

Levonorgestrel‐intrauterine system effects on hemostasis and menstrual blood loss in women seeking contraception

The purpose of the study is to determine the effects of levonorgestrel use on hemostasis, and menstrual blood loss over 24 months in a cohort of women seeking contraception. Data from 30 women (median age 36 years) were analyzed. Samplings at pre-insertion, 1 and 3 months for blood and additional endometrial aspirates at 2 and 6 months were performed. Systemic determination for hemoglobin, hematocrit, computerized thromboelastography, tissue-type plasminogen activator, urokinase-like plasminogen activator and receptor, plasminogen activator inhibitor-1/2, D-dimer and von Willebrand Factor was performed. In endometrial extracts, tissue-type plasminogen activator, urokinase-like plasminogen activator and receptor and plasminogen activator inhibitor-1/2 were assayed. The Menstrual Blood Loss Pictorial Chart Score for measurement of menstrual blood loss was carried out for 24 months. There were no significant changes in systemic hemostasis within 3 months of device use. In the endometrium, there was a significant increase in tissue-type plasminogen activator antigen, plasminogen activator inhibitor-1/2 and urokinase-like plasminogen activator receptor levels from pre-insertion state, with the highest level seen by 6 months. Amenorrhea was seen in 20% of women by 6 months and 50% by 24 months. Enhanced expression of plasminogen activator inhibitor-1/2 in the presence of increased urokinase-like plasminogen activator receptor and tissue-type plasminogen activator antigen was seen in the endometrium. The effects on hemostasis appear to be localized in the endometrium. Systemic hemostasis was not duly affected and menstrual blood loss was reduced. No women in the study had a pregnancy or expulsion of the levonorgestrel-intrauterine system device in the 24 months of the study period.