Protein expression profiling suggests relevance of noncanonical pathways in isolated pulmonary embolism.

Patients with isolated pulmonary embolism (PE) have a distinct clinical profile from those with deep vein thrombosis (DVT)-associated PE, with more pulmonary conditions and atherosclerosis. These findings suggest a distinct molecular pathophysiology and the potential involvement of alternative pathways in isolated PE. To test this hypothesis, data from 532 individuals from the Genotyping and Molecular Phenotyping of Venous ThromboEmbolism Project, a multicenter prospective cohort study with extensive biobanking, were analyzed. Targeted, high-throughput proteomics, machine learning, and bioinformatic methods were applied to contrast the acute-phase plasma proteomes of isolated PE patients (n = 96) against those of patients with DVT-associated PE (n = 276) or isolated DVT (n = 160). This resulted in the identification of shared molecular processes between PE phenotypes, as well as an isolated PE-specific protein signature. Shared processes included upregulation of inflammation, response to oxidative stress, and the loss of pulmonary surfactant. The isolated PE-specific signature consisted of 5 proteins: interferon-γ, glial cell line-derived neurotrophic growth factor, polypeptide N-acetylgalactosaminyltransferase 3, peptidyl arginine deiminase type-2, and interleukin-15 receptor subunit α. These proteins were orthogonally validated using cis protein quantitative trait loci. External replication in an independent population-based cohort (n = 5778) further validated the proteomic results and showed that they were prognostic for incident primary isolated PE in individuals without history of VTE (median time to event: 2.9 years; interquartile range: 1.6-4.2 years), supporting their possible involvement in the early pathogenesis. This study has identified molecular overlaps and differences between VTE phenotypes. In particular, the results implicate noncanonical pathways more commonly associated with respiratory and atherosclerotic disease in the acute pathophysiology of isolated PE.

Plasma ACE2 and risk of death or cardiometabolic diseases: a case-cohort analysis.

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is an endogenous counter-regulator of the renin-angiotensin hormonal cascade. We assessed whether plasma ACE2 concentrations were associated with greater risk of death or cardiovascular disease events. METHODS: We used data from the Prospective Urban Rural Epidemiology (PURE) prospective study to conduct a case-cohort analysis within a subset of PURE participants (from 14 countries across five continents: Africa, Asia, Europe, North America, and South America). We measured plasma concentrations of ACE2 and assessed potential determinants of plasma ACE2 levels as well as the association of ACE2 with cardiovascular events. FINDINGS: We included 10 753 PURE participants in our study. Increased concentration of plasma ACE2 was associated with increased risk of total deaths (hazard ratio [HR] 1·35 per 1 SD increase [95% CI 1·29-1·43]) with similar increases in cardiovascular and non-cardiovascular deaths. Plasma ACE2 concentration was also associated with higher risk of incident heart failure (HR 1·27 per 1 SD increase [1·10-1·46]), myocardial infarction (HR 1·23 per 1 SD increase [1·13-1·33]), stroke (HR 1·21 per 1 SD increase [1·10-1·32]) and diabetes (HR 1·44 per 1 SD increase [1·36-1·52]). These findings were independent of age, sex, ancestry, and traditional cardiac risk factors. With the exception of incident heart failure events, the independent relationship of ACE2 with the clinical endpoints, including death, remained robust after adjustment for BNP. The highest-ranked determinants of ACE2 concentrations were sex, geographic ancestry, and body-mass index (BMI). When compared with clinical risk factors (smoking, diabetes, blood pressure, lipids, and BMI), ACE2 was the highest ranked predictor of death, and superseded several risk factors as a predictor of heart failure, stroke, and myocardial infarction. INTERPRETATION: Increased plasma ACE2 concentration was associated with increased risk of major cardiovascular events in a global study. FUNDING: Canadian Institute of Health Research, Heart & Stroke Foundation of Canada, and Bayer.

Correction: Multimorbidity in patients with heart failure from 11 Asian regions: A prospective cohort study using the ASIAN-HF registry.

[This corrects the article DOI: 10.1371/journal.pmed.1002541.].

Multimorbidity in patients with heart failure from 11 Asian regions: A prospective cohort study using the ASIAN-HF registry.

BACKGROUND: Comorbidities are common in patients with heart failure (HF) and complicate treatment and outcomes. We identified patterns of multimorbidity in Asian patients with HF and their association with patients' quality of life (QoL) and health outcomes. METHODS AND FINDINGS: We used data on 6,480 patients with chronic HF (1,204 with preserved ejection fraction) enrolled between 1 October 2012 and 6 October 2016 in the Asian Sudden Cardiac Death in Heart Failure (ASIAN-HF) registry. The ASIAN-HF registry is a prospective cohort study, with patients prospectively enrolled from in- and outpatient clinics from 11 Asian regions (Hong Kong, Taiwan, China, Japan, Korea, India, Malaysia, Thailand, Singapore, Indonesia, and Philippines). Latent class analysis was used to identify patterns of multimorbidity. The primary outcome was defined as a composite of all-cause mortality or HF hospitalization within 1 year. To assess differences in QoL, we used the Kansas City Cardiomyopathy Questionnaire. We identified 5 distinct multimorbidity groups: elderly/atrial fibrillation (AF) (N = 1,048; oldest, more AF), metabolic (N = 1,129; obesity, diabetes, hypertension), young (N = 1,759; youngest, low comorbidity rates, non-ischemic etiology), ischemic (N = 1,261; ischemic etiology), and lean diabetic (N = 1,283; diabetic, hypertensive, low prevalence of obesity, high prevalence of chronic kidney disease). Patients in the lean diabetic group had the worst QoL, more severe signs and symptoms of HF, and the highest rate of the primary combined outcome within 1 year (29% versus 11% in the young group) (p for all <0.001). Adjusting for confounders (demographics, New York Heart Association class, and medication) the lean diabetic (hazard ratio [HR] 1.79, 95% CI 1.46-2.22), elderly/AF (HR 1.57, 95% CI 1.26-1.96), ischemic (HR 1.51, 95% CI 1.22-1.88), and metabolic (HR 1.28, 95% CI 1.02-1.60) groups had higher rates of the primary combined outcome compared to the young group. Potential limitations include site selection and participation bias. CONCLUSIONS: Among Asian patients with HF, comorbidities naturally clustered in 5 distinct patterns, each differentially impacting patients' QoL and health outcomes. These data underscore the importance of studying multimorbidity in HF and the need for more comprehensive approaches in phenotyping patients with HF and multimorbidity. TRIAL REGISTRATION: ClinicalTrials.gov NCT01633398.

Androgen inhibits key atherosclerotic processes by directly activating ADTRP transcription.

Low androgen levels are associated with an increased risk of coronary artery disease (CAD), thrombosis and myocardial infarction (MI), suggesting that androgen has a protective role. However, little is known about the underlying molecular mechanism. Our genome-wide association study identified the ADTRP gene encoding the androgen-dependent TFPI regulating protein as a susceptibility gene for CAD and MI. The expression level of ADTRP was regulated by androgen, but the molecular mechanism is unknown. In this study, we identified the molecular mechanism by which androgen regulates ADTRP expression and tested the hypothesis that androgen plays a protective role in cardiovascular disease by activating ADTRP expression. Luciferase assays with an ADTRP promoter luciferase reporter revealed that androgen regulated ADTRP transcription in a dose- and time-dependent manner, and the effect was abolished by three different androgen inhibitors, including pyrvinium pamoate, bicalutamide, and cyproterone acetate. Chromatin-immunoprecipitation showed that the androgen receptor bound to a half androgen response element (ARE, TGTTCT) located at +324bp from the ADTRP transcription start site. The ARE is required for concentration-dependent transcriptional activation of ADTRP. HL-60 monocyte adhesion to EAhy926 endothelial cells (ECs) and transmigration across the EC layer, the two processes critical to development of CAD and MI, were inhibited by androgen, but the effect was rescued by ADTRP siRNA and exacerbated by overexpression of ADTRP and its downstream genes PIK3R3 and MIA3. These data suggest that one molecular mechanism by which androgen confers protection against CAD is stimulation of ADTRP expression.

Coronary atherosclerosis burden, but not transient troponin elevation, predicts long-term outcome in recreational marathon runners.

We determined the prognostic value of transient increases in high-sensitive serum troponin I (hsTnI) during a marathon and its association with traditional cardiovascular risk factors and imaging-based risk markers for incident coronary events and all-cause mortality in recreational marathon runners. Baseline data of 108 marathon runners, 864 age-matched controls and 216 age- and risk factor-matched controls from the general population were recorded and their coronary event rates and all-cause mortality after 6 ± 1 years determined. hsTnI was measured in 74 marathon finishers before and after the race. Other potential predictors for coronary events, i.e., Framingham Risk Score (FRS), coronary artery calcium (CAC) and presence of myocardial fibrosis as measured by magnetic resonance imaging-based late gadolinium enhancement (LGE), were also assessed. An increase beyond the 99 % hsTnI-threshold, i.e., 0.04 µg/L, was observed in 36.5 % of runners. FRS, CAC, or prevalent LGE did not predict hsTnI values above or increases in hsTnI beyond the median after the race, nor did they predict future events. However, runners with versus without LGE had higher hsTnI values after the race (median (Q1/Q3), 0.08 µg/L (0.04/0.09) versus 0.03 µg/L (0.02/0.06), p = 0.039), and higher increases in hsTnI values during the race (median (Q1/Q3), 0.05 µg/L (0.03/0.08) versus 0.02 µg/L (0.01/0.05), p = 0.0496). Runners had a similar cumulative event rate as age-matched or age- and risk factor-matched controls, i.e., 6.5 versus 5.0 % or 4.6 %, respectively. Event rates in runners with CAC scores <100, 100-399, and ≥400 were 1.5, 12.0, and 21.4 % (p = 0.002 for trend) and not different from either control group. Runners with coronary events had a higher prevalence of LGE than runners without events (57 versus 8 %, p = 0.003). All-cause mortality was similar in marathon runners (3/108, 2.8 %) and controls (26/864, 3.0 % or 5/216, 2.4 %, respectively). Recreational marathon runners with prevalent myocardial fibrosis develop higher hsTnI values during the race than those without. Increasing coronary artery calcium scores and prevalent myocardial fibrosis, but not increases in hsTnI are associated with higher coronary event rates. All-cause mortality in marathon runners is similar to that in risk factor-matched controls.

Unsupervised clustering of venous thromboembolism patients by clinical features at presentation identifies novel endotypes that improve prognostic stratification.

BACKGROUND: Individuals with acute venous thromboembolism (VTE) constitute a heterogeneous group of patients with diverse clinical characteristics and outcome. OBJECTIVES: To identify endotypes of individuals with acute VTE based on clinical characteristics at presentation through unsupervised cluster analysis and to evaluate their molecular proteomic profile and clinical outcome. METHODS: Data from 591 individuals from the Genotyping and Molecular phenotyping of Venous thromboembolism (GMP-VTE) project were explored. Hierarchical clustering was applied to 58 variables to define VTE endotypes. Clinical characteristics, three-year incidence of thromboembolic events or death, and acute-phase plasma proteomics were assessed. RESULTS: Four endotypes were identified, exhibiting different patterns of clinical characteristics and clinical course. Endotype 1 (n = 300), comprising older individuals with comorbidities, had the highest incidence of thromboembolic events or death (HR [95 % CI]: 3.76 [1.96-7.19]), followed by endotype 4 (n = 127) (HR [95 % CI]: 2.55 [1.26-5.16]), characterised by men with history of VTE and provoking risk factors, and endotype 3 (n = 57) (HR [95 % CI]: 1.57 [0.63-3.87]), composed of young women with provoking risk factors, vs. reference endotype 2 (n = 107). The reference endotype was constituted by individuals diagnosed with PE without comorbidities, who had the lowest incidence of the investigated endpoint. Differentially expressed proteins associated with the endotypes were related to distinct biological processes, supporting differences in molecular pathophysiology. The endotypes had superior prognostic ability compared to existing risk stratifications such as provoked vs unprovoked VTE and D-dimer levels. CONCLUSION: Four endotypes of VTE were identified by unsupervised phenotype-based clustering that diverge in clinical outcome and plasmatic protein signature. This approach might support the future development of individualized treatment in VTE.

Partial adenosine A1 receptor agonists for cardiovascular therapies.

Adenosine, a purine nucleoside, is present in all cells in tightly regulated concentrations. It has many different physiological effects in the whole body and in the heart. Adenosine activates four G protein-coupled receptors A1, A2a, A2b, and A3. Activation of myocardial A1 receptors has been shown to inhibit a variety of myocardial pathologies associated with ischemia and reperfusion injury, including stunning, arrhythmogenesis, coronary and ventricular dysfunction, acute myocardial infarction, apoptosis, and chronic heart failure, implying several options for new cardiovascular therapies for diseases, like angina pectoris, control of cardiac rhythm, ischemic injury during an acute coronary syndrome, or heart failure. However, the main issue of using full A1 receptor agonists in such indications is the broad physiologic spectrum of cardiac and extracardiac effects. Desired A1 receptor-mediated protective and regenerative cardiovascular effects might be counter-regulated by unintended side effects when considering full A1 receptor agonists. These effects can be overcome by partial A1 agonists. Partial A1 agonists can be used to trigger only some of the physiological responses of receptor activation depending on endogenous adenosine levels and on receptor reserve in different tissues. CV-Therapeutics reported the identification of a partial A1 receptor agonist CVT-3619, and recently, another partial A1 receptor agonist VCP28 was published. Both compounds are adenosine derivatives. Adenosine-like A1 receptor agonists often have the drawback of a short half-life and low bioavailability, making them not suitable for chronic oral therapy. We identified the first non-adenosine-like partial A1 receptor agonist(s) with pharmacokinetics optimal for oral once daily treatment and characterized the qualities of the partial character of the A1 receptor agonist(s) in preclinical and clinical studies.

Variation of platelet function in clinical phenotypes of acute venous thromboembolism - Results from the GMP-VTE project.

BACKGROUND: The role of platelets in the pathogenesis of venous thromboembolism (VTE) is receiving increasing attention; however, limited information is available on platelet function in the acute phase of the disease. OBJECTIVE: To characterize platelet function according to VTE phenotypes. PATIENTS/METHODS: In total, 154 subjects (isolated pulmonary embolism [iPE], n = 28; isolated deep vein thrombosis [iDVT], n = 35; DVT+PE, n = 91) were included. In this study platelet function analyzer (PFA)-200, light transmission aggregometry (LTA), thrombin generation (TG) in presence (PRP) and absence (PFP) of platelets and platelet flow cytometry were investigated. LASSO regression was used to select clinical and platelet biomarkers that distinguish between VTE phenotypes. RESULTS: PFA-200 results did not differ between VTE phenotypes. LTA from DVT+PE subjects showed lowest maximum aggregation after epinephrine and adenosine diphosphate compared to iPE and iDVT. Lower % of PAC-1-positive platelets after in-vitro trigger were present in DVT+PE and iPE compared to iDVT. TG in PRP had lower peak height and velocity in DVT+PE and iPE against iDVT. The results of LASSO regression for the distinction between DVT+PE vs iDVT identified 18 variables (AUC =0.93) of which 72% were platelet biomarkers. For distinction between iPE and iDVT, 10 variables were selected (AUC = 0.96) of which 50% were platelet-related. Obesity was the only variable weakly discriminating between DVT+PE vs iPE (AUC = 0.66). CONCLUSION: This explorative study suggests an important distinction between PE-related phenotypes and iDVT when considering clinical and platelet function data. Lower platelet-dependent TG along with reduced platelet reactivity suggest higher platelet degranulation in PE-dependent phenotypes compared to iDVT.

Association of FXI activity with thrombo-inflammation, extracellular matrix, lipid metabolism and apoptosis in venous thrombosis.

Animal experiments and early phase human trials suggest that inhibition of factor XIa (FXIa) safely prevents venous thromboembolism (VTE), and specific murine models of sepsis have shown potential efficacy in alleviating cytokine storm. These latter findings support the role of FXI beyond coagulation. Here, we combine targeted proteomics, machine learning and bioinformatics, to discover associations between FXI activity (FXI:C) and the plasma protein profile of patients with VTE. FXI:C was measured with a modified activated partial prothrombin time (APTT) clotting time assay. Proximity extension assay-based protein profiling was performed on plasma collected from subjects from the Genotyping and Molecular Phenotyping of Venous Thromboembolism (GMP-VTE) Project, collected during an acute VTE event (n = 549) and 12-months after (n = 187). Among 444 proteins investigated, N = 21 and N = 66 were associated with FXI:C during the acute VTE event and at 12 months follow-up, respectively. Seven proteins were identified as FXI:C-associated at both time points. These FXI-related proteins were enriched in immune pathways related to causes of thrombo-inflammation, extracellular matrix interaction, lipid metabolism, and apoptosis. The results of this study offer important new avenues for future research into the multiple properties of FXI, which are of high clinical interest given the current development of FXI inhibitors.

Subtype-specific plasma signatures of platelet-related protein releasate in acute pulmonary embolism.

INTRODUCTION: There is evidence that plasma protein profiles differ in the two subtypes of pulmonary embolism (PE), isolated PE (iPE) and deep vein thrombosis (DVT)-associated PE (DVT-PE), in the acute phase. The aim of this study was to determine specific plasma signatures for proteins related to platelets in acute iPE and DVT-PE compared to isolated DVT (iDVT). METHODS: Within the Genotyping and Molecular Phenotyping of Venous ThromboEmbolism (GMP-VTE) Project, a multicenter prospective cohort study of 693 confirmed VTE cases, a highly sensitive targeted proteomics approach based on dual-antibody proximity extension assay was applied. LASSO-regularized logistic regression analysis selected 33 and 30 of 135 platelet-related candidate proteins in iPE and DVT-PE vs. iDVT, respectively. RESULTS: All regulated proteins were well associated with six prominently released platelet proteins and the majority showed specificity for iPE and DVT-PE compared to iDVT. While iPE-specific proteins were assigned to be predominantly released via shedding mechanisms and extracellular vesicles, granule secretion was identified as a major release mechanism assigned to DVT-associated PE-specific proteins. Network analysis demonstrated three interconnected clusters of specifically regulated proteins in iPE linked to immunoreceptor signaling, pathogen clearance and chemotaxis, whereas for DVT-associated PE one cluster linked to tissue remodeling and leukocyte trafficking. Machine learning-based analysis reveals specific plasma signatures and differential release mechanisms of proteins related to platelets in acute iPE and DVT-associated PE. CONCLUSION: These data suggest that the platelet protein releasate contributes to the differential regulation of plasma proteins in acute PE compared to iDVT, which may be associated with different platelet activation patterns.

A targeted proteomics investigation of the obesity paradox in venous thromboembolism.

The obesity paradox, the controversial finding that obesity promotes disease development but protects against sequelae in patients, has been observed in venous thromboembolism (VTE). The aim of this investigation was to identify a body mass-related proteomic signature in VTE patients and to evaluate whether this signature mediates the obesity paradox in VTE patients. Data from the Genotyping and Molecular Phenotyping in Venous ThromboEmbolism Project, a prospective cohort study of 693 VTE patients, were analyzed. A combined end point of recurrent VTE or all-cause death was used. Relative quantification of 444 proteins was performed using high-throughput targeted proteomics technology. Measurements were performed in samples collected during the acute VTE event and at 12-month follow-up. An 11-protein signature (CLEC4C, FABP4, FLT3LG, IL-17C, LEP, LYVE1, MASP1, ST2, THBS2, THBS4, TSLP) for body mass in VTE patients was identified. The signature did not significantly mediate the obesity paradox (change in hazard ratio [HR]: 0.04; likelihood ratio test of nested models = 7.7; P = .74), but its main constituent protein, leptin, was inversely associated with recurrent VTE or death (adjusted HR [95% confidence interval] per standard deviation increase: 0.66 [0.46-0.94]). This relationship was significantly (P = .007) modified by markers of leptin resistance (ie, high body mass index and high circulating matrix metalloproteinase-2 levels). Although the signature did not substantially explain the obesity paradox, leptin appears to be protective against disease recurrence and death in VTE patients. This protective effect was abrogated under conditions of leptin resistance and hence was unrelated to the obesity paradox.

Imatinib ameliorates fibrosis in uraemic cardiac disease in BALB/c without improving cardiac function.

BACKGROUND: Cardiovascular disease is one of the major causes of mortality and morbidity in patients with end-stage renal disease (ESRD). It is characterized by multiple left ventricular abnormalities, referred to as 'uraemic cardiomyopathy'. The aim of the study was to investigate uraemic cardiac disease in a mouse model of chronic renal failure induced by subtotal nephrectomy and to evaluate the impact of the tyrosine kinase inhibitor imatinib and its antifibrotic as well as functional properties on the extent of the disease. METHODS: Male BALB/c mice were sham operated (SH) or subtotally nephrectomized and either left untreated (5/6) or treated with imatinib (5/6+I: 10 mg/kg/day p.o.) for up to 24 weeks. Cardiac and arterial structure and function were analysed using echocardiography, histology, extent of lipid peroxidation and myography, respectively. RESULTS: Subtotal nephrectomy resulted in cardiac dysfunction characterized by reduced fractional shortening (SH: 21.6 +/- 4.7%; 5/6: 11.1 +/- 2.4%; 5/6+I: 8.4 +/- 2.7%; P < 0.05) and ejection fraction (SH: 38.8 +/- 4.5%; 5/6: 26.1 +/- 2.8%; 5/6+I: 18.6 +/- 2.6%; P < 0.05) after 24 weeks. This was associated with impaired endothelium-dependent vasodilatation in mesenteric resistance vessels and elevated cardiac malondialdehyde concentrations as a marker of lipid peroxidation. In this model, the continuous application of the tyrosine kinase inhibitor imatinib was associated with less myocardial fibrosis (SH: 2.52 +/- 0.34%; 5/6: 5.50 +/- 0.18%; 5/6+I: 3.52 +/- 0.52%; P < 0.05), but did not preserve myocardial function. CONCLUSIONS: Uraemic cardiac disease in BALB/c results in fibrosis, oxidative damage and endothelial dysfunction. However, the anti-fibrotic activity of imatinib did not ameliorate cardiac dysfunction. Thus, our data suggest that uraemic cardiac disease in this mouse model is driven by oxidative damage and endothelial dysfunction.

A novel functional haplotype in the human GNAS gene alters Galphas expression, responsiveness to beta-adrenoceptor stimulation, and peri-operative cardiac performance.

AIMS: Cardiac overexpression of the beta-adrenoceptor-coupled G-protein subunit Galphas in mice enhances inotropic responses to sympathetic stimulation, but evokes cardiomyopathy with increasing age. We tested whether functional single nucleotide polymorphisms (SNPs) in the human Galphas (GNAS) gene modulate Galphas expression and assessed functional consequences. METHODS AND RESULTS: Sequencing the promoter and intron 1 of GNAS revealed 11 SNPs resulting in three common haplotypes. Haplotype *3 constructs exhibited significantly higher promoter activity than haplotypes *1 and *2, resulting in a more than 50% higher Galphas mRNA expression in homozygous *3 carriers (*3/*3) than in heterozygous (*3/-) and negative *3 (-/-) carriers (P = 0.002). Basal, Galphas- (via NaF and GTP) and isoproterenol-stimulated adenylyl cyclase (AC) activities were also significantly higher in *3/*3 than in *3/- and -/- carriers. In contrast, direct AC activation via forskolin was independent of GNAS haplotypes. Furthermore, haemodynamic measurements in 137 coronary artery bypass patients revealed a higher cardiac index in *3/*3 carriers than in *3/- and -/- carriers (P = 0.025) associated with a lower NYHA functional class (P = 0.040) and serum NT-proBNP concentrations (P = 0.002). CONCLUSION: SNPs in regulatory regions of GNAS impact upon Galphas expression and stimulated cAMP formation in human hearts in vitro and upon cardiac performance in vivo.

Comprehensive platelet phenotyping supports the role of platelets in the pathogenesis of acute venous thromboembolism - results from clinical observation studies.

BACKGROUND: The pathogenesis of arterial and venous thrombosis is in large part interlaced. How much platelet phenotype relates to acute venous thromboembolism (VTE) independent of the underlying cardiovascular profile is presently poorly investigated. METHODS: Platelet count and mean platelet volume (MPV), platelet aggregation in whole blood and platelet rich plasma (PRP), platelet-dependent thrombin generation (TG) and platelet surface activation markers were measured under standardized conditions. Machine learning was applied to identify the most relevant characteristics associated with VTE from a large array (N = 58) of clinical and platelet-related variables. FINDINGS: VTE cases (N = 159) presented with lower platelet count and MPV vs controls (N = 140). Whole blood aggregation showed shorter collagen/Epinephrine closure times in cases, particularly within acetylsalicylic acid (ASA) users. Within ASA users, higher PRP aggregation after adenosine diphosphate (ADP), epinephrine, collagen and arachidonic acid was observed in cases vs controls. Within non-ASA and/or subjects on anticoagulants, cases presented with lower aggregation after ADP and collagen vs controls. Lower platelet-dependent TG, higher CD63 on resting and lower PAC-1 expression after collagen/ADP in-vitro stimulated platelets further characterized VTE cases vs controls, independent of therapy. Lasso regression analysis identified 26 variables associated with VTE of which 69% were platelet-related. INTERPRETATION: Comprehensive phenotyping of platelet function identified a large proportion of low responders to ASA in VTE cases. Lower platelet-dependent TG and lower platelet reactivity after ex-vivo stimulation characterized the "platelet exhausted syndrome" in cases. Finally, from a large array of covariates including clinical risk factors, platelet biomarkers comprised 69% of all selected variables differentiating VTE cases vs controls. FUNDING: German Federal Ministry of Education and Research, CTH-Mainz and Bayer AG.

Missing value imputation in proximity extension assay-based targeted proteomics data.

Targeted proteomics utilizing antibody-based proximity extension assays provides sensitive and highly specific quantifications of plasma protein levels. Multivariate analysis of this data is hampered by frequent missing values (random or left censored), calling for imputation approaches. While appropriate missing-value imputation methods exist, benchmarks of their performance in targeted proteomics data are lacking. Here, we assessed the performance of two methods for imputation of values missing completely at random, the previously top-benchmarked 'missForest' and the recently published 'GSimp' method. Evaluation was accomplished by comparing imputed with remeasured relative concentrations of 91 inflammation related circulating proteins in 86 samples from a cohort of 645 patients with venous thromboembolism. The median Pearson correlation between imputed and remeasured protein expression values was 69.0% for missForest and 71.6% for GSimp (p = 5.8e-4). Imputation with missForest resulted in stronger reduction of variance compared to GSimp (median relative variance of 25.3% vs. 68.6%, p = 2.4e-16) and undesired larger bias in downstream analyses. Irrespective of the imputation method used, the 91 imputed proteins revealed large variations in imputation accuracy, driven by differences in signal to noise ratio and information overlap between proteins. In summary, GSimp outperformed missForest, while both methods show good overall imputation accuracy with large variations between proteins.

ADTRP regulates TFPI expression via transcription factor POU1F1 involved in coronary artery disease.

Genomic variants in both ADTRP and TFPI genes are associated with risk of coronary artery disease (CAD). ADTRP regulates TFPI expression and endothelial cell functions involved in the initiation of atherosclerotic CAD. ADTRP also specifies primitive myelopoiesis and definitive hematopoiesis by upregulating TFPI expression. However, the underlying molecular mechanism is unknown. Here we show that transcription factor POU1F1 is the key by which ADTRP regulates TFPI expression. Luciferase reporter assays, chromatin-immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA) in combination with analysis of large and small deletions of the TFPI promoter/regulatory region were used to identify the molecular mechanism by which ADTRP regulates TFPI expression. Genetic association was assessed using case-control association analysis and phenome-wide association analysis (PhenGWA). ADTRP regulates TFPI expression at the transcription level in a dose-dependent manner. The ADTRP-response element was localized to a 50 bp region between -806 bp and -756 bp upstream of TFPI transcription start site, which contains a binding site for POU1F1. Deletion of POU1F1-binding site or knockdown of POU1F1 expression abolished ADTRP-mediated transcription of TFPI. ChIP and EMSA demonstrated that POU1F1 binds to the ADTRP response element. Genetic analysis identified significant association between POU1F1 variants and risk of CAD. PhenGWA identified other phenotypic traits associated with the ADTRP-POU1F1-TFPI axis such as lymphocyte count (ADTRP), waist circumference (TFPI), and standing height (POU1F1). These data identify POU1F1 as a transcription factor that regulates TFPI transcription in response to ADTRP, and link POU1F1 variants to risk of CAD for the first time.

Serotoninergic and non-serotoninergic effects of two tricyclic antidepressants on visceral nociception in a rat model.

OBJECTIVE: Tricyclic antidepressants (TCAs) are well established in the treatment of patients with irritable bowel syndrome (IBS). The effects are believed to be linked to serotoninergic antinociceptive properties, but data on the antinociceptive effects of various TCAs with variable serotoninergic and non-serotoninergic properties have not been investigated. The aim of this study was to compare the antinociceptive effects of different TCAs. MATERIAL AND METHODS: Colorectal distension (CRD) using a barostat device was carried out in rats and the visceromotor response (VMR) to CRD was quantified by abdominal wall electromyography. Prior to CRD, saline (control), amitriptyline (AM), desipramine (DES), reserpine (RES) or a combination of TCAs and RES (AM + RES or DES + RES) was applied intraperitoneally. Serum 5-HT levels were determined using high-performance liquid chromatography (HPLC). RES was used to antagonize the serotoninergic actions of TCAs in order to discriminate between these effects and others. RESULTS: Both TCAs decreased the VMR compared to placebo. After RES application without TCAs, the VMR was increased compared to controls (6403 microV+/-1772 microV). Co-administration of AM and RES resulted in a modest decrease in VMR (5774 microV+/-1953 microV), while in rats treated with RES and DES the VMR again was significantly lower (3446 microV (+/-1347 microV; p <0.05)). 5-HT levels were higher in TCA pretreated rats than those in controls and significantly lower 5-HT levels were found in all rats pretreated with RES. CONCLUSIONS: AM and DES have antinociceptive properties while RES is pro-nociceptive. The antinociceptive effects of DES are not abolished by RES pretreatment, while AM only attenuates the pro-nociceptive effects of RES. The non-serotoninergic properties of TCAs substantially contribute to the differences in the antinococeptive effects of various TCAs.

Heart failure with preserved ejection fraction in Asia.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a global public health problem. Unfortunately, little is known about HFpEF across Asia. METHODS AND RESULTS: We prospectively studied clinical characteristics, echocardiographic parameters and outcomes in 1204 patients with HFpEF (left ventricular ejection fraction ≥50%) from 11 Asian regions, grouped as Northeast Asia (Hong Kong, Taiwan, China, Japan, Korea, n = 543), South Asia (India, n = 252), and Southeast Asia (Malaysia, Thailand, Singapore, Indonesia, Philippines, n = 409). Mean age was 68 ±12 years (37% were < 65 years) and 50% were women. Seventy per cent of patients had ≥2 co-morbidities, most commonly hypertension (71%), followed by anaemia (57%), chronic kidney disease (50%), diabetes (45%), coronary artery disease (29%), atrial fibrillation (29%) and obesity (26%). Southeast Asian patients had the highest prevalence of all co-morbidities except atrial fibrillation, South Asians had the lowest prevalence of all co-morbidities except anaemia and obesity, and Northeast Asians had more atrial fibrillation. Left ventricular hypertrophy and concentric remodelling were most prominent among Southeast and South Asians, respectively (P < 0.001). Overall, 12.1% of patients died or were hospitalized for heart failure within 1 year. Southeast Asians were at higher risk for adverse outcomes, independent of co-morbidity burden and cardiac geometry. CONCLUSION: These first prospective multinational data from Asia show that HFpEF affects relatively young patients with a high burden of co-morbidities. Regional differences in types of co-morbidities, cardiac remodelling and outcomes of HFpEF across Asia have important implications for public health measures and global HFpEF trial design.

Impact of atherosclerotic plaque composition on coronary microembolization during percutaneous coronary interventions.

BACKGROUND: Cardiac marker release after percutaneous coronary interventions (PCI) reflects myocardial necrosis which is usually the result of periprocedural (micro)embolization of atherothrombotic debris and associated with impaired left ventricular function and adverse outcome. METHODS: In this prospective study, we examined 55 patients treated by direct stenting of single de-novo lesions to assess the relationship between plaque composition, as determined by preinterventional intravascular ultrasound (IVUS) with radiofrequency data (IVUS-RF) analysis (so-called Virtual Histology) versus coronary microembolization, as determined by serial measurement of cardiac markers. IVUS was performed with an electronic system and 20-MHz IVUS catheters. Serum creatine kinase (CK) and cardiac troponin I (CTnI) were determined before PCI and after 6, 12, and 24 hours. RESULTS: Plaques had a volume of 99 +/- 63 mm(3) and were composed of fibrous (61 +/- 9%) and fibro-fatty tissue (27 +/- 12%), dense calcium (4 +/- 3%), and necrotic core (NC) (8 +/- 6%). NC volume per se, volume per 10 mm of segment length, and volume % were correlated (r = 0.64, 0.66, and 0.52 respectively; all P < 0.01) with the maximum increase in cardiac markers (CK 55.4 +/- 55.7 U/l; CTnI 0.49 +/- 0.68 ng/ml). Patients in the 4th quartile of NC volume (>10.8 mm(3)) had a particularly high increase in markers (P < 0.001). In contrast, total plaque volume and plaque components other than NC had no relation with cardiac markers (ns). CONCLUSIONS: Patients with large NC in culprit lesions may experience more myocardial injury from peri-interventional microembolization. IVUS-RF assessment before PCI has the potential to identify lesions at particular high risk which may help to tailor PCI.