Novel heart failure biomarkers: why do we fail to exploit their potential?

Update on cardiovascular prevention in clinical practice: A position paper of the European Association of Preventive Cardiology of the European Society of Cardiology

European guidelines on cardiovascular prevention in clinical practice were first published in 1994 and have been regularly updated, most recently in 2016, by the Sixth European Joint Task Force. Given the amount of new information that has become available since then, components from the task force and experts from the European Association of Preventive Cardiology of the European Society of Cardiology were invited to provide a summary and critical review of the most important new studies and evidence since the latest guidelines were published. The structure of the document follows that of the previous document and has six parts: Introduction (epidemiology and cost effectiveness); Cardiovascular risk; How to intervene at the population level; How to intervene at the individual level; Disease-specific interventions; and Settings: where to intervene? In fact, in keeping with the guidelines, greater emphasis has been put on a population-based approach and on disease-specific interventions, avoiding re-interpretation of information already and previously considered. Finally, the presence of several gaps in the knowledge is highlighted.

Pharmacological myeloperoxidase (MPO) inhibition in an obese/hypertensive mouse model attenuates obesity and liver damage, but not cardiac remodeling

Lifestyle factors are important drivers of chronic diseases, including cardiovascular syndromes, with low grade inflammation as a central player. Attenuating myeloperoxidase (MPO) activity, an inflammatory enzyme associated with obesity, hypertension and heart failure, could have protective effects on multiple organs. Herein, the effects of the novel oral available MPO inhibitor AZM198 were studied in an obese/hypertensive mouse model which displays a cardiac phenotype. Eight week old male C57BL6/J mice received 16 weeks of high fat diet (HFD) combined with angiotensin II (AngII) infusion during the last 4 weeks, with low fat diet and saline infusion as control. Treated animals showed therapeutic AZM198 levels (2.1 µM), corresponding to 95% MPO inhibition. AZM198 reduced elevated circulating MPO levels in HFD/AngII mice to normal values. Independent of food intake, bodyweight increase and fat accumulation were attenuated by AZM198, alongside with reduced visceral adipose tissue (VAT) inflammation and attenuated severity of nonalcoholic steatohepatitis. The HFD/AngII perturbation caused impaired cardiac relaxation and contraction, and increased cardiac hypertrophy and fibrosis. AZM198 treatment did, however, not improve these cardiac parameters. Thus, AZM198 had positive effects on the main lipid controlling tissues in the body, namely adipose tissue and liver. This did, however, not directly result in improved cardiac function.

Novel Molecular Targets Participating in Myocardial Ischemia-Reperfusion Injury and Cardioprotection

Worldwide morbidity and mortality from acute myocardial infarction (AMI) and related heart failure remain high. While effective early reperfusion of the criminal coronary artery after a confirmed AMI is the typical treatment at present, collateral myocardial ischemia-reperfusion injury (MIRI) and pertinent cardioprotection are still challenging to address and have inadequately understood mechanisms. Therefore, unveiling the related novel molecular targets and networks participating in triggering and resisting the pathobiology of MIRI is a promising and valuable frontier. The present study specifically focuses on the recent MIRI advances that are supported by sophisticated bio-methodology in order to bring the poorly understood interrelationship among pro- and anti-MIRI participant molecules up to date, as well as to identify findings that may facilitate the further investigation of novel targets.

Inflammatory and Molecular Pathways in Heart Failure-Ischemia, HFpEF and Transthyretin Cardiac Amyloidosis

Elevated pro-inflammatory biomarkers and cytokines are associated with morbidity and mortality in heart failure (HF). Preclinical and clinical studies have shown multiple inflammatory mechanisms causing cardiac remodeling, dysfunction and chronic failure. Therapeutics in trials targeting the immune response in heart failure and its effects did not result in evident benefits regarding clinical endpoints and mortality. This review elaborates pathways of immune cytokines in pathogenesis and worsening of heart failure in clinical and cellular settings. Besides the well-known mechanisms of immune activation and inflammation in atherosclerosis causing ischemic cardiomyopathy or myocarditis, attention is focused on other mechanisms leading to heart failure such as transthyretin (TTR) amyloidosis or heart failure with preserved ejection fraction. The knowledge of the pathogenesis in heart failure and amyloidosis on a molecular and cellular level might help to highlight new disease defining biomarkers and to lead the way to new therapeutic targets.

Log-transformed B-type natriuretic peptide as a prognostic predictor in patients undergoing cardiovascular surgery

Objective

This study was performed to explore the association between circulating B-type natriuretic peptide (BNP) and other mortality-related factors in patients undergoing cardiovascular surgery.

Methods

In this observational study, multilevel linear regression analysis and multilevel survival analysis were performed to measure the log-transformed BNP (lnBNP) value at four time points in 197 patients with 788 repeated data measurements. Effects of the interaction between the time points and the two intervention groups (cardiac surgery and vascular surgery) were also investigated. Six models were evaluated to identify the best fit for the data. Stata/MP® version 14.2 (Stata Corp., College Station, TX, USA) was used to analyze the two-level variance component model fitting.

Results

There were significant differences in the fixed-effect parameters of lnBNP, such as the time point, age, body mass index, emergency operation, prognostic nutritional index, and estimated glomerular filtration rate. According to the multilevel survival analysis for all-cause death and vascular death, lnBNP significantly differed and was a common prognostic marker.

Conclusion

As lnBNP increased by 1 point, all-cause death increased 2.07 times and vascular death increased 3.10 times. lnBNP is an important prognostic predictor and quantitative biochemical marker in patients undergoing cardiovascular surgery.

Galectin-3-Mediated Glial Crosstalk Drives Oligodendrocyte Differentiation and (Re)myelination

Galectin-3 (Gal-3) is the only chimeric protein in the galectin family. Gal-3 structure comprises unusual tandem repeats of proline and glycine-rich short stretches bound to a carbohydrate-recognition domain (CRD). The present review summarizes Gal-3 functions in the extracellular and intracellular space, its regulation and its internalization and secretion, with a focus on the current knowledge of Gal-3 role in central nervous system (CNS) health and disease, particularly oligodendrocyte (OLG) differentiation, myelination and remyelination in experimental models of multiple sclerosis (MS). During myelination, microglia-expressed Gal-3 promotes OLG differentiation by binding glycoconjugates present only on the cell surface of OLG precursor cells (OPC). During remyelination, microglia-expressed Gal-3 favors an M2 microglial phenotype, hence fostering myelin debris phagocytosis through TREM-2b phagocytic receptor and OLG differentiation. Gal-3 is necessary for myelin integrity and function, as evidenced by myelin ultrastructural and behavioral studies from LGALS3^-/- mice. Mechanistically, Gal-3 enhances actin assembly and reduces Erk 1/2 activation, leading to early OLG branching. Gal-3 later induces Akt activation and increases MBP expression, promoting gelsolin release and actin disassembly and thus regulating OLG final differentiation. Altogether, findings indicate that Gal-3 mediates the glial crosstalk driving OLG differentiation and (re)myelination and may be regarded as a target in the design of future therapies for a variety of demyelinating diseases.

Plasma levels of heart failure biomarkers are primarily a reflection of extracardiac production

Plasma heart failure (HF) biomarkers, like natriuretic peptides, are important in diagnosis, prognosis and HF treatment. Several novel HF biomarkers have been identified, including Gal-3, GDF-15 and TIMP-1, but their clinical potential remains vague. Here we investigated plasma biomarker levels in relation to tissue expression and structural and functional cardiac changes. Methods: Cardiac remodeling, cardiac function, and plasma and tissue biomarker levels were investigated in mice after myocardial infarction induced by temporal and permanent LAD ligation (tLAD and pLAD). In addition, a pressure overload model induced by transverse aortic constriction (TAC) and an obese/hypertensive HFpEF-like mouse model were investigated. Results: Plasma levels of ANP and its cardiac expression were strictly associated with cardiac remodeling and function. Gal-3, GDF-15 and TIMP-1 cardiac expressions were also related to cardiac remodeling and function, but not their plasma levels. Only directly after myocardial infarction could elevated plasma levels of Gal-3 and TIMP-1 be detected. Eight weeks after infarction, plasma levels were not elevated despite enhanced cardiac expression and low EF (18.3±3.3%, pLAD). Plasma levels of TIMP-1 and GDF-15 were elevated after TAC, but this also correlated with increased lung expression and congestion. In obese-hypertensive mice, elevated plasma levels of Gal-3, GDF-15 and TIMP1 were associated with increased adipose tissue expression and not with cardiac function. Conclusions: The Gal-3, GDF-15 and TIMP-1 plasma pool levels are hardly influenced by dynamic changes in cardiac expression. These biomarkers are not specific for indices of cardiac remodeling, but predominantly reflect stress in other affected tissues and hence provide health information beyond the heart.