Project description:Background Neprilysin is a transmembrane endopeptidase involved in the breakdown of a variety of vasoactive peptides and serves as a therapeutic target in heart failure with reduced ejection fraction (HFrEF). This study aimed to investigate the relationship of circulating neprilysin with neurohumoral activation and the impact of plasma neprilysin activity on prognosis in HFrEF. Methods and Results A total of 369 chronic HFrEF patients were enrolled prospectively. Plasma neprilysin concentration and activity were determined by a specific ELISA and a fluorometric method. The association between plasma neprilysin and heart failure (HF) severity, neurohumoral activation, ie norepinephrine and absolute renin concentration, as well as all-cause mortality was assessed. Median plasma neprilysin concentrations and activity levels were 413 pg/mL (interquartile range 0-4111) and 2.36 nmol/mL per minute (interquartile range 1.16-4.59). No correlation could be shown between plasma neprilysin concentrations and activity (rs=0.09, P=0.088). Plasma neprilysin activity correlated with HF severity reflected by New York Heart Association stage (P=0.003) and tertiles of N-terminal pro-B-type natriuretic peptide (P<0.001), whereas neprilysin concentrations did not (P=0.220; P=0.849). There was no relevant relationship between plasma neprilysin concentrations and activity, with neurohumoral activation reflected by absolute renin concentration (rs=-0.02, P=0.648; rs=0.03, P=0.574) or norepinephrine levels (rs=-0.06, P=0.248; rs=0.20, P<0.001). Neither circulating neprilysin concentrations nor activity were associated with outcome. Conclusions Plasma neprilysin concentrations and activity are not directly related to neurohumoral activation, indicating that neprilysin regulation is either more complex or not correctly mirrored by circulating neprilysin as a biomarker. Circulating neprilysin concentrations and activity were not associated with overall survival, implicating limited prognostic value of plasma neprilysin measurements in HFrEF patients.
Project description:AimsHeart failure (HF) patients may lack improvement of left ventricular (LV) ejection fraction (LVEF) despite optimal HF medication comprising an angiotensin receptor-neprilysin inhibitor (ARNI). Therefore, we aimed to identify key predictors for LV functional enhancement and prognostic reverse cardiac remodelling in HF patients on ARNI treatment.MethodsWe retrospectively analysed 294 consecutive patients with HF with reduced (HFrEF) or mildly reduced (HFmrEF) ejection fraction in our 'EnTruth' patient registry. LVEF was determined by echocardiography at initiation of ARNI and at 12 months of follow-up. We assessed the predictive value of clinically relevant patient-, HF- and treatment-related parameters in regard to changes in LVEF and all-cause mortality using medoid clustering and the XGBoost machine learning algorithm.ResultsCluster analysis integrating clinically relevant patient characteristics unveiled four characteristic sub-phenotypes of patients with HFrEF and HFmrEF, respectively. Distinct clusters exhibit a strong (P < 0.05) therapeutic response to ARNI treatment and enhanced LV function. Key patient criteria, such as duration and aetiology of HF, renal function and de novo ARNI treatment, were significantly (P < 0.05) associated with change of LVEF and independently predicted cardiac remodelling. By training various machine learning models on relevant clinical parameters, stratification of LVEF improvement by XGBoost resulted in a high prediction accuracy. The stratification of patients with HFrEF [area under the receiver operating characteristic curve (AUC) = 0.77] and HFmrEF (AUC = 0.70) led to an increased diagnostic accuracy of LVEF improvement in the validation cohort. Using machine learning, the likelihood of cardiac remodelling following ARNI treatment, as indicated by our newly established EnTruth score, was directly associated with absolute LVEF improvement in both HFrEF (r = 0.51, P < 0.0001) and HFmrEF (r = 0.42, P = 0.001). Ultimately, patients with HFrEF and a high EnTruth score have a lower risk of all-cause mortality (P < 0.05 in survival analysis).ConclusionsRecognition of essential clinical factors by integrating machine learning and cluster analyses may help to identify HF patients benefiting from improvement of LVEF following ARNI treatment. Early identification of those patients with a high response to ARNI treatment may allow a more refined selection of patients benefiting from an early escalation of HF treatment or interventional therapy.
Project description:BackgroundFew studies have compared the performances of those reported miRNAs as biomarkers for heart failure with reduced EF (HFrEF) in a population at high risk. The purpose of this study is to investigate comprehensively the performance of those miRNAs as biomarkers for HFrEF.MethodsBy using bioinformatics methods, we also examined these miRNAs' target genes and possible signal transduction pathways. We collected serum samples from patients with HFrEF at Zhongshan Hospital. Receiver operating characteristic (ROC) curves were used to evaluate the accuracy of those miRNAs as biomarkers for HFrEF. miRWALK2.0, Gene Ontology (GO) analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed to predict the target genes and pathways of selected miRNAs.ResultsThe study included 48 participants, of whom 30 had HFrEF and 18 had hypertension with normal left ventricular ejection fraction (LVEF). MiR-378, miR-195-5p were significantly decreased meanwhile ten miRNAs were remarkably elevated (miR-21-3p, miR-21-5p, miR-106-5p, miR-23a-3p, miR-208a-3p, miR-1-3p, miR-126-5p, miR-133a-3p, miR-133b, miR-223-3p) in the serum of the HFrEF group.ConclusionThe combination of miR 133a-3p, miR 378, miR 1-3p, miR 106b-5p, and miR 133b has excellent diagnostic performance for HFrEF, and there is a throng of mechanisms and pathways by which regulation of these miRNAs may affect the risk of HFrEF.
Project description:PurposeCirculating endothelial cells (CECs) and progenitor cells are currently evaluated as potential biomarkers of antiangiogenic therapy. CD146 is considered a panendothelial-specific marker, but its utility as a CEC marker in cancer patients remains unclear.Patients and methodsWe analyzed the expression of CD146 on mononuclear blood cells, primary tissue endothelial cells, and malignant and normal tissues by flow cytometric and immunohistochemical analyses. Furthermore, we measured the circulation kinetics of CD146+ cells before, and then 3 and 12 days after vascular endothelial growth factor (VEGF) antibody blockade by bevacizumab infusion in rectal cancer patients enrolled in a phase I trial.ResultsIn the peripheral blood of these cancer patients, over 90% of the CD146+ cells were CD45+ hematopoietic cells. CD146 expression was primarily detected on a subset of CD3+CD4+ lymphocytes, and was undetectable on CD34+CD133+CD45(dim) progenitor cells or CD31(bright)CD45- viable CECs. In contradistinction, CD146 was detectable in tissues on both cellular components of tumor vessel wall: CD31(bright)CD45- endothelial cells and alpha-SMA+ pericytes. Unlike viable CECs and progenitor cells, CD146+ cell concentration in the peripheral blood of cancer patients did not decrease during VEGF blockade.ConclusionCD146 is fairly homogeneously expressed on vascular endothelium but not on viable CECs or progenitor cells. The vast majority of CD146+ blood cells are lymphocytes, and VEGF blockade by bevacizumab did not significantly change their number in rectal cancer patients. These results underscore the need for further characterization and identification of new markers for CEC subpopulations for their development as biomarkers of antiangiogenic therapy.
Project description:AimsRecent updates of international treatment guidelines for heart failure with reduced ejection fraction (HFrEF) differ regarding the use of angiotensin receptor neprilysin inhibitor (ARNI) as first-line treatment. The American Heart Association/American College of Cardiology/Heart Failure Society of America (AHA/ACC/HFSA) 2022 guidelines gives ARNI a Class IA recommendation for HFrEF patients while the European Society of Cardiology's guidelines are less clear when ARNI could be considered as first line treatment option in de novo patients. This study aimed to model the clinical and budgetary outcomes of implementing these guidelines, comparing conservative ARNI prescription patterns with less conservative in Sweden and in the United Kingdom.Methods and resultsA health economic model was developed to compare different treatment patterns for HFrEF. Incident cohorts were included on an annual basis and followed over 10 years. The model included treatment specific all-cause mortality and hospitalization rates, as well as drug acquisition, monitoring, and hospitalization costs. Increasing the use of ARNI could lead to about 7000-12 300 life years gained and 2600-4600 hospitalizations prevented in Sweden. These health benefits come with an additional cost of 112-195 million euros. Similar results were estimated for the United Kingdom, albeit on a larger population.ConclusionsIncreasing the proportion of patients receiving ARNI instead of angiotensin converting enzyme inhibitors as first-line treatment of HFrEF will lead to a considerable number of additional life years gained and prevented hospitalizations but with additional cost in terms of health care expenditure in Sweden and in the United Kingdom.
Project description:Both ppGpp and pppGpp are thought to function collectively as second messengers for many complex cellular responses to nutritional stress throughout biology. There are few indications that their regulatory effects might be different; however, this question has been largely unexplored for lack of an ability to experimentally manipulate the relative abundance of ppGpp and pppGpp. Here, we achieve preferential accumulation of either ppGpp or pppGpp with Escherichia coli strains through induction of different Streptococcal (p)ppGpp synthetase fragments. In addition, expression of E. coli GppA, a pppGpp 5'-gamma phosphate hydrolase that converts pppGpp to ppGpp, is manipulated to fine tune differential accumulation of ppGpp and pppGpp. In vivo and in vitro experiments show that pppGpp is less potent than ppGpp with respect to regulation of growth rate, RNA/DNA ratios, ribosomal RNA P1 promoter transcription inhibition, threonine operon promoter activation and RpoS induction. To provide further insights into regulation by (p)ppGpp, we have also determined crystal structures of E. coli RNA polymerase-σ(70) holoenzyme with ppGpp and pppGpp. We find that both nucleotides bind to a site at the interface between β' and ω subunits.
Project description:BackgroundIn heart failure with reduced ejection fraction (HFrEF), elevated soluble neprilysin (sNEP) levels are associated with an increased risk of cardiovascular death, and its inhibition with sacubitril/valsartan has improved survival.ObjectivesThis study sought to determine the relevance of sNEP as a biomarker in heart failure with preserved ejection fraction (HFpEF) and to compare circulating sNEP levels in patients with HFpEF with normal controls.MethodsA case-control study was performed in 242 symptomatic patients with HFpEF previously enrolled in the Phosphodiesterase-5 Inhibition to Improve Clinical Status and Exercise Capacity in Heart Failure with Preserved Ejection Fraction (RELAX) and Nitrates's Effect on Activity Tolerance in Heart Failure With Preserved Ejection (NEAT-HFpEF) clinical trials and 891 asymptomatic subjects without HF or diastolic dysfunction (confirmed by NT-proBNP levels <200 pg/ml and echocardiography) who were enrolled in the Prevalence of Asymptomatic Left Ventricular Dysfunction study. sNEP was measured using a sandwich enzyme-linked immunosorbent assay (ELISA) in all subjects.ResultsOverall, sNEP levels were lower in HFpEF compared with controls (3.5 ng/ml; confidence interval [CI]: 2.5 to 4.8 vs. 8.5 ng/ml; CI: 7.2 to 10.0; p < 0.001). After adjusting for age, gender, body mass index (BMI), and smoking history, mean sNEP levels were also lower in HFpEF compared with controls (4.0 ng/ml [CI: 2.7 to 5.4] vs. 8.2 ng/ml [CI: 6.8 to 9.7]; p = 0.002). The cohorts were propensity matched based on age, BMI, diabetes, hypertension, smoking history, and renal function, and sNEP levels remained lower in HFpEF compared with controls (median 2.4 ng/ml [interquartile range: 0.6 to 27.7] vs. 4.9 ng/ml [interquartile range: 1.2 to 42.2]; p = 0.02).ConclusionsPatients with HFpEF on average have significantly lower circulating sNEP levels compared with controls. These findings challenge our current understanding of the complex biology of circulating sNEP in HFpEF.
Project description:Despite significant advances in disease modifying therapy in heart failure (HF), diuretics have remained the cornerstone of volume management in all HF phenotypes. Diuretics, alongside their definite acute haemodynamic and symptomatic benefits, also possess many possible deleterious side effects. Moreover, questions remain regarding the prognostic impact of chronic diuretic use. To date, few data exist pertaining to diuretic reduction as a result of individual traditional guideline directed medical therapy in HF with reduced ejection fraction (HFrEF). However, diuretic reduction has been demonstrated with sacubitril/valsartan (angiotensin receptor-neprilysin inhibitor [ARNi]) from the PARADIGM study, as well as, post-marketing reports from our own group and others. Whether the ARNi compound represents the dawn of a new era, where effective therapies will have a more noticeable reduction on diuretic need, remains to be seen. The emergence of sodium glucose transport 2 inhibitors and guanylate cyclase stimulators may further exemplify this issue and potentially extend this benefit to HF patients outside of the HFrEF phenotype. In conclusion, emerging new therapies in HFrEF could reduce the reliance on diuretics in the management of this phenotype of HF. These developments further highlight the clinical importance to continually assess an individual's diuretic requirements through careful volume assessment.
Project description:Chronic inflammation plays a crucial role in coronary artery disease (CAD), but differences in specific cytokine profiles between acute coronary syndrome (ACS) and stable CAD remain unknown. We investigated cytokine differences between these two manifestations of CAD. The study included 308 patients with angiographically detected, hemodynamically significant CAD: 150 patients undergone angiography for ACS, 158 patients undergone angiography for stable CAD. To assess dynamic changes, 116 patients had index angiogram at least 3 months earlier. We measured the serum concentrations of 48 circulating cytokines. The ACS group had decreased interleukin (IL) 4 (p = 0.005), and increased IL-8 (p = 0.008), hepatocyte growth factor (HGF) (p < 0.001) and macrophage colony-stimulating factor (M-CSF) (p = 0.002) levels compared with the stable CAD group. Multivariable logistic regression revealed increased levels of HGF (OR 18.050 [95% CI 4.372-74.517], p < 0.001), M-CSF (OR 2.257 [1.375-3.705], p = 0.001) and IL-6 (OR 1.586 [1.131-2.224], p = 0.007), independently associated with ACS. In the post-angiography group, only diminished platelet-derived growth factor-BB levels in ACS-manifested patients were observed (OR 0.478, [0.279-0.818], p = 0.007). Cytokine profiles differ between ACS and stable CAD. Such differences seem to be mainly reversible within 3 months after ACS. Thus, targeting one or two cytokines only might not offer one-size fits all-therapeutic approach for CAD-associated inflammation.Trial registration: NCT03444259.
Project description:BackgroundHFrEF is a heterogenous condition with high mortality. We used serial assessments of 4210 circulating proteins to identify distinct novel protein-based HFrEF subphenotypes and to investigate underlying dynamic biological mechanisms. Herewith we aimed to gain pathophysiological insights and fuel opportunities for personalised treatment.MethodsIn 382 patients, we performed trimonthly blood sampling during a median follow-up of 2.1 [IQR:1.1-2.6] years. We selected all baseline samples and two samples closest to the primary endpoint (PEP; composite of cardiovascular mortality, HF hospitalization, LVAD implantation, and heart transplantation) or censoring, and applied an aptamer-based multiplex proteomic approach. Using unsupervised machine learning methods, we derived clusters from 4210 repeatedly measured proteomic biomarkers. Sets of proteins that drove cluster allocation were analysed via an enrichment analysis. Differences in clinical characteristics and PEP occurrence were evaluated.FindingsWe identified four subphenotypes with different protein profiles, prognosis and clinical characteristics, including age (median [IQR] for subphenotypes 1-4, respectively:70 [64, 76], 68 [60, 79], 57 [47, 65], 59 [56, 66]years), EF (30 [26, 36], 26 [20, 38], 26 [22, 32], 33 [28, 37]%), and chronic renal failure (45%, 65%, 36%, 37%). Subphenotype allocation was driven by subsets of proteins associated with various biological functions, such as oxidative stress, inflammation and extracellular matrix organisation. Clinical characteristics of the subphenotypes were aligned with these associations. Subphenotypes 2 and 3 had the worst prognosis compared to subphenotype 1 (adjHR (95%CI):3.43 (1.76-6.69), and 2.88 (1.37-6.03), respectively).InterpretationFour circulating-protein based subphenotypes are present in HFrEF, which are driven by varying combinations of protein subsets, and have different clinical characteristics and prognosis.Clinical trial registrationClinicalTrials.gov Identifier: NCT01851538https://clinicaltrials.gov/ct2/show/NCT01851538.FundingEU/EFPIA IMI2JU BigData@Heart grant n°116074, Jaap Schouten Foundation and Noordwest Academie.