Effects of MASP-1 of the Complement System on Activation of Coagulation Factors and Plasma Clot Formation

BACKGROUND: Numerous interactions between the coagulation and complement systems have been shown. Recently, links between coagulation and mannan-binding lectin-associated serine protease-1 (MASP-1) of the complement lectin pathway have been proposed. Our aim was to investigate MASP-1 activation of factor XIII (FXIII), fibrinogen, prothrombin, and thrombin-activatable fibrinolysis inhibitor (TAFI) in plasma-based systems, and to analyse effects of MASP-1 on plasma clot formation, structure and lysis. METHODOLOGY/PRINCIPAL FINDINGS: We used a FXIII incorporation assay and specific assays to measure the activation products prothrombin fragment F1+2, fibrinopeptide A (FPA), and activated TAFI (TAFIa). Clot formation and lysis were assessed by turbidimetric assay. Clot structure was studied by scanning electron microscopy. MASP-1 activated FXIII and, contrary to thrombin, induced FXIII activity faster in the Val34 than the Leu34 variant. MASP-1-dependent generation of F1+2, FPA and TAFIa showed a dose-dependent response in normal citrated plasma (NCP), albeit MASP-1 was much less efficient than FXa or thrombin. MASP-1 activation of prothrombin and TAFI cleavage were confirmed in purified systems. No FPA generation was observed in prothrombin-depleted plasma. MASP-1 induced clot formation in NCP, affected clot structure, and prolonged clot lysis. CONCLUSIONS/SIGNIFICANCE: We show that MASP-1 interacts with plasma clot formation on different levels and influences fibrin structure. Although MASP-1-induced fibrin formation is thrombin-dependent, MASP-1 directly activates prothrombin, FXIII and TAFI. We suggest that MASP-1, in concerted action with other complement and coagulation proteins, may play a role in fibrin clot formation

Catecholamine up-regulates MMP-7 expression by activating AP-1 and STAT3 in gastric cancer

<p>Abstract</p> <p>Background</p> <p>Stress, anxiety and depression can cause complex physiological and neuroendocrine changes, resulting in increased level of stress related hormone catecholamine, which may constitute a primary mechanism by which physiological factors impact gene expression in tumors. In the present study, we investigated the effects of catecholamine stimulation on MMP-7 expression in gastric cancer cells and elucidated the molecular mechanisms of the up-regulation of MMP-7 level by catecholamine through an adrenergic signaling pathway.</p> <p>Results</p> <p>Increased MMP-7 expression was identified at both mRNA and protein levels in the gastric cancer cells in response to isoproterenol stimulation. β2-AR antigonist effectively abrogated isoproterenol-induced MMP-7 expression. The activation of STAT3 and AP-1 was prominently induced by isoproterenol stimulation and AP-1 displayed a greater efficacy than STAT3 in isoproterenol-induced MMP-7 expression. Mutagenesis of three STAT3 binding sites in MMP-7 promoter failed to repress the transactivation of MMP-7 promoter and silencing STAT3 expression was not effective in preventing isoproterenol-induced MMP-7 expression. However, isoproterenol-induced MMP-7 promoter activities were completely disappeared when the AP-1 site was mutated. STAT3 and c-Jun could physically interact and bind to the AP-1 site, implicating that the interplay of both transcriptional factors on the AP-1 site is responsible for isoproterenol-stimulated MMP-7 expression in gastric cancer cells. The expression of MMP-7 in gastric cancer tissues was found to be at the site where β2-AR was overexpressed and the levels of MMP-7 and β2-AR were the highest in the metastatic locus of gastric cancer.</p> <p>Conclusions</p> <p>Up-regulation of MMP-7 expression through β2-AR-mediated signaling pathway is involved in invasion and metastasis of gastric cancer.</p

Matrix Metalloproteinases-8 and-9 and Tissue Inhibitor of Metalloproteinase-1 in Burn Patients. A Prospective Observational Study

Introduction Matrix metalloproteinases (MMPs) -8 and -9 are released from neutrophils in acute inflammation and may contribute to permeability changes in burn injury. In retrospective studies on sepsis, levels of MMP-8, MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) differed from those of healthy controls, and TIMP-1 showed an association with outcome. Our objective was to investigate the relationship between these proteins and disease severity and outcome in burn patients. Methods In this prospective, observational, two-center study, we collected plasma samples from admission to day 21 post-burn, and burn blister fluid samples on admission. We compared MMP-8, -9, and TIMP-1 levels between TBSA20% (N = 30) injured patients and healthy controls, and between 90-day survivors and non-survivors. MMP-8, -9, and TIMP-1 levels at 24-48 hours from injury, their maximal levels, and their time-adjusted means were compared between groups. Correlations with clinical parameters and the extent of burn were analyzed. MMP-8, -9, and TIMP-1 levels in burn blister fluids were also studied. Results Plasma MMP-8 and -9 were higher in patients than in healthy controls (P20% groups. MMP-8 and -9 were not associated with clinical severity or outcome measures. TIMP-1 differed significantly between patients and controls (P20% groups (PPeer reviewe

Soluble neprilysin and survival in critically ill patients

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): -) Association for the Promotion of Research on Arteriosclerosis, Thrombosis and Vascular Biology (ATVB) -) Ludwig Boltzmann Cluster for Cardiovascular Research BACKGROUND Critically ill patients admitted to an intensive care unit (ICU) exhibit a high mortality rate irrespective of the initial cause of hospitalization. Neprilysin is a neutral endopeptidase degrading an array of vasoactive peptides, including bradykinin, adrenomedullin and natriuretic peptides and became a drug target within the treatment of heart failure with reduced ejection fraction. The aim of this study was to analyze whether circulating levels of neprilysin at ICU admission are associated with 30-day mortality, due to its physiologic effects. METHODS In this single-center prospective observational study, 222 consecutive patients admitted to a tertiary ICU at a university hospital were included. Blood was drawn at admission and soluble neprilysin levels were measured using ELISA. RESULTS Median simplified acute physiology score was 44 and 30-day mortality was 35.1% in medical patients (n = 151) and 7.1% in patients after surgery and heart valve interventions (n = 71). Neprilysin levels did not differ according to survival status after 30 days and admission type. When assessing neprilysin and survival according to admission type, no association was found in medical patients, while in patients after surgery or heart valve intervention, 30-day survivors exhibited significantly lower neprilysin levels as compared to those that died within 30 days (660.2, IQR: 156.4 – 2512.5 pg/ml versus 6532.6, IQR: 1840.1 – 10000.0 pg/ml; p = 0.02). Neprilysin predicted mortality independently from age, gender, NT-proBNP, and SAPS II score (OR per 1-SD increase of neprilysin: 2.52, 95%CI 1.01–6.32; p = 0.049). Additionally, neprilysin was markedly elevated in patients with sepsis and septic shock (p &amp;lt; 0.05). CONCLUSION At the time of ICU-admission, circulating levels of neprilysin independently predicted 30-day mortality in patients following cardiac surgery or heart valve intervention, but not in critically ill medical patients. </jats:sec

Indications, outcomes and complications after ECMO implantation in the cath lab - a single-center retrospective study

Abstract Funding Acknowledgements Type of funding sources: None. Background Despite the increase of extracorporeal membrane oxygenation (ECMO) employment around the globe over the last decades, studies describing the emergency use of venoarterial (VA)-ECMO in the cardiac catheterization laboratory (CCL) are scarce. Purpose The aim of this study was to describe the patient population that received ECMO in the CCL of a tertiary care center and the associated complications and outcomes. Methods In this single-center retrospective study we reviewed the baseline clinical and laboratory characteristics, indications and outcomes of adult patients, who received VA-ECMO between 2011 and 2019. Results In the given time period, ECMO use in the CCL increased drastically. Mean age of the 83 patients was 58.3 ± 12.5 years, 78.3% were male. From 2011 to 2018 ECMO-use in the CCL increased drastically. The most common indication for ECMO implantation was cardiac arrest (66%), followed by cardiogenic shock (12%), high-risk PCI (11%), and procedure-related complications (10%). While 30-day mortality in the total study population was 69%, it varied greatly depending on the underlying indication for ECMO therapy (cardiac arrest 78%, cardiogenic shock 20%, high-risk PCI 44%, procedure-related complications 88%). The most commonly occurring complications were acute kidney injury (20%) and cannula site bleeding (20%), followed by extremity complications (19%), sepsis (18%), major bleeding (10%) and stroke (8%). Of interest, patients receiving ECMO therapy after in-hospital cardiac arrest showed greater survival rates (28.2%) as compared to patients after out of hospital cardiac arrest (18.2%; p=0.045). High serum lactate levels (p=0.018) and low baseline pH values (p=0.001) at baseline were associated with a significantly increased 30-day mortality after ECMO implantation. Conclusion The emergency use of VA-ECMO in the CCL increased over the last years and was associated with a high 30-day mortality in our study population. Still, a &amp;gt;20% survival rate in the group of patients with refractory cardiac arrest, an otherwise futile situation, suggests that VA-ECMO implantation is reasonable in selected patients. As high admission serum lactate levels and the baseline pH are strong predictors of outcome, such parameters may be used to guide decision making. </jats:sec

Circulating levels of proprotein convertase subtilisin/kexin type 9 (PCSK9) are associated with monocyte subsets in patients with stable coronary artery disease

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): FWF Background and aims Proprotein convertase subtilisin/kexin type-9 (PCSK9) is an enzyme promoting the degradation of low-density lipoprotein receptors (LDL-R) in hepatocytes. Inhibition of PCSK9 has emerged as a novel target for lipid-lowering therapy. Monocytes are crucially involved in the pathogenesis of atherosclerosis and can be divided into three subsets. The aim of this study was to examine whether circulating levels of PCSK9 are associated with monocyte subsets. Methods We included 69 patients with stable coronary artery disease. PCSK9 levels were measured and monocyte subsets were assessed by flow cytometry and divided into classical monocytes (CD14++CD16-; CM), intermediate monocytes (CD14++CD16+; IM) and non-classical monocytes (CD14 + CD16++; NCM). Results Mean age was 64 years and 80% of patients were male. Patients on statin treatment (n = 55) showed higher PCSK9-levels (245.4 (206.0-305.5) ng/mL) as opposed to those without statin treatment (186.1 (162.3-275.4) ng/mL; p = 0.05). In patients on statin treatment, CM correlated with circulating PCSK9 levels (R = 0.29; p = 0.04), while NCM showed an inverse correlation with PCSK9 levels (R=-0.33; p = 0.02). Patients with PCSK9 levels above the median showed a significantly higher proportion of CM as compared to patients with PCSK-9 below the median (83.5 IQR 79.2-86.7 vs. 80.4, IQR 76.5-85.2%; p = 0.05). Conversely, PCSK9 levels &amp;gt;median were associated with a significantly lower proportion of NCM as compared to those with PCSK9 &amp;lt;median (10.2, IQR 7.3-14.6 vs. 14.3, IQR 10.9-18.7%; p = 0.02). In contrast, IM showed no association with PCSK-9 levels. Conclusions We hereby provide a novel link between PCSK9 regulation, innate immunity and atherosclerotic disease in statin-treated patients. </jats:sec

Soluble neprilysin and survival in critically ill patients

Abstract Funding Acknowledgements Type of funding sources: None. Background Critically ill patients admitted to an intensive care unit (ICU) exhibit a high mortality rate irrespective of the initial cause of hospitalization. Neprilysin, a neutral endopeptidase degrading an array of vasoactive peptides became a drug target within the treatment of heart failure with reduced ejection fraction.The aim of this study was to analyze whether circulating levels of neprilysin at ICU admission are associated with 30-day mortality. Methods In this single-center prospective observational study, 222 consecutive patients admitted to a tertiary ICU at a university hospital were included. Blood was drawn at admission and soluble neprilysin levels were measured using ELISA. Results In the total cohort, Soluble neprilysin levels did not differ according to survival status after 30 days as well as type of admission. However, in patients after surgery or heart valve intervention, 30-day survivors exhibited significantly lower circulating neprilysin levels as compared to those who died within 30 days (660.2, IQR: 156.4 – 2512.5 pg/ml versus 6532.6, IQR: 1840.1 – 10000.0 pg/ml; p=0.02). Soluble neprilysin predicted mortality independently from age, gender, and commonly used scores of risk-prediction (EuroSCORE II, STS-score, and SAPS II score). Additionally, soluble neprilysin was markedly elevated in patients with sepsis and septic shock (p&amp;lt;0.05). Conclusion At the time of ICU-admission, circulating levels of neprilysin independently predicted 30-day mortality in patients following cardiac surgery or heart valve intervention, but not in critically ill medical patients. Furthermore, patients suffering from sepsis and septic shock displayed significantly increased circulating neprilysin levels. </jats:sec