Rapid transcriptional activation and early mRNA turnover of brain natriuretic peptide in cardiocyte hypertrophy. Evidence for brain natriuretic peptide as an "emergency" cardiac hormone against ventricular overload

Multiple Biomarkers to Predict Major Adverse Cardiovascular Events in Patients With Coronary Chronic Total Occlusions

There are limited tools available to predict the long-term prognosis of persons with coronary chronic total occlusions (CTO). A previously described blood biomarker panel to predict cardiovascular (CV) events was evaluated in patients with CTO. From 1,251 patients in the CASABLANCA study, 241 participants with a CTO were followed for an average of 4 years for occurrence of major adverse CV events (MACE, CV death, nonfatal myocardial infarction or stroke) and CV death/heart failure (HF) hospitalization. Results of a biomarker panel (kidney injury molecule-1, N-terminal pro-B-type natriuretic peptide, osteopontin, and tissue inhibitor of metalloproteinase-1) from baseline samples were expressed as low-, medium-, and high-risk. By 4 years, a total of 67 (27.8%) MACE and 56 (23.2%) CV death/HF hospitalization events occurred. The C-statistic of the panel for MACE through 4 years was 0.79 (p < 0.001). Considering the low-risk group as referent, the hazard ratio (HR) of MACE by 4 years was 6.65 (95% confidence interval [CI]: 2.98 to 14.8) and 12.4 (95% CI:5.17 to 29.6) for the medium and high-risk groups (both p < 0.001). The C-statistic for CVD/HF hospitalization by 4 years was 0.84 (p < 0.001). Compared to the low-risk score group, the medium and high-risk groups had HR of 5.61 (95% CI: 2.33 to 13.5) and 15.6 (95% CI: 6.18, 39.2; both p value <0.001). In conclusion, a multiple biomarker panel assisted in discriminating a broad range of risk for adverse outcomes in patients with coronary CTO. These results may have implications for risk stratification, patient care and could have a role for clinical trial enrichment.

A Characterization of the Nonclinical Pharmacology and Toxicology of Aficamten, a Reversible Allosteric Inhibitor of Cardiac Myosin

Aficamten (CK-3773274) is a cardiac myosin inhibitor in development for the treatment of hypertrophic cardiomyopathy (HCM), a commonly inherited heart condition often characterized as a disease of the sarcomere. Aficamten reduces pathologic cardiac hypercontractility by selectively binding to an allosteric site on cardiac myosin. To characterize the pharmacology and toxicology of aficamten, a series of nonclinical repeated dose studies were conducted. In a 10-day repeated dose pharmacology study in Sprague Dawley rats, aficamten produced dose-dependent reductions in left ventricular fractional shortening (FS) which were fully reversible within 24 h. Aficamten did not change the ratio of heart weight to tibia length (HW/TL) or left ventricular posterior wall (LVPW) thickness at any dose tested. At a supratherapeutic dose of 6 mg/kg/day, there was a significant increase in interventricular septum (IVS) thickness. Aficamten did not affect mRNA expression of the cardiac injury biomarkers BNP, β-MHC, or ANP. In repeated dose Good Laboratory Practice (GLP) regulatory toxicology studies in Sprague Dawley rats for up to 6 months and beagle dogs for up to 9 months, the primary adverse findings at supratherapeutic doses were consistent across all studies and observed in the heart consisting of atrial/ventricular dilatation that correlated with increased heart weights. These findings were largely reversible and consistent with excessive on-target pharmacology associated with cardiac myosin inhibition. The reversible nature of aficamten-associated adverse effects is supportive of its clinical safety as this property suggests that these findings, should they occur in humans, may also be reversible, limiting long-term human cardiac risk.

Impact of preoperative brain natriuretic peptide level for predicting postoperative respiratory complications

Background

Predicting respiratory complications after pulmonary surgery is important for thoracic surgeons. This study aimed to clarify the relationship between preoperative brain natriuretic peptide (BNP) levels and postoperative respiratory complications (PRC).

Methods

A total of 383 patients with primary or metastatic lung cancer who underwent surgical resection were included in this retrospective study. The cut-off value of elevated BNP was set as 35 pg/mL, and its relationship with PRCs was analyzed. Risk factors for PRCs were determined using a logistic regression model.

Results

Among the patients, 66 (17%) experienced PRCs: 24% vs. 14% with BNP levels ≥35 and <35 pg/mL, respectively (P=0.02). In patients with a BNP level ≥35 pg/mL, the development of PRCs was higher in those who underwent lobectomy (34%) than in those who underwent sublobar resection (14%) (P=0.01). Univariate [odds ratio (OR): 1.947, 95% confidence interval (CI): 1.13-3.352, P=0.02] and multivariate (OR: 1.838, 95% CI: 1.032-3.273, P=0.04) analyses revealed a significant association between a preoperative BNP level ≥35 pg/mL and a higher risk of PRCs in all patients.

Conclusions

Preoperative BNP levels ≥35 pg/mL were associated with an increased risk for PRCs, suggesting its potential utility for identifying patients with elevated risk for PRCs before pulmonary surgery.

Effect of heart rate on B-type natriuretic peptide in sinus rhythm

B-type natriuretic peptide (BNP) levels accurately reflect the degree of cardiac overload in heart failure. Considering cardiac morphology and intracardiac pressure, including the left ventricular end-systolic volume index (LVESVI) and left ventricular end-diastolic volume index (LVEDVI), is essential for cardiac overload assessment. These indexes influence plasma BNP levels, and high heart rate is likely associated with cardiac morphology. However, the direct relationship between high heart rate and plasma BNP levels remains unknown. In this study, we simultaneously measured various hemodynamic parameters and plasma BNP levels during cardiac catheterization in 5,429 inpatients with sinus rhythm at our hospital. Furthermore, we examined how heart rate is associated with cardiac morphology, intracardiac pressure, and plasma BNP levels via regression analysis and structure equation modeling (SEM). Univariate regression analysis revealed a significant positive correlation between heart rate and log BNP. The path model with SEM revealed significant positive relations of heart rate and LVESVI with left ventricular end-diastolic pressure, in addition to a significant negative relation of heart rate and LVEDVI with log BNP. Collectively, these findings suggest no positive relation (rather, a negative relation) between heart rate and log BNP and that high heart rate is indirectly associated with increased plasma BNP levels by altering cardiac morphology and intracardiac pressure.

Blunted increase in plasma BNP during acute coronary syndrome attacks in obese patients

Background

Unexpectedly low natriuretic peptide (NP) levels in proportion to heart failure severity are often observed in obese individuals. However, the magnitude of NP elevation in response to acute cardiac stress in obesity has not yet been extensively studied. This study aimed to determine the impact of obesity on the increase in plasma NP in response to cardiac hemodynamic stress during acute coronary syndrome (ACS) attacks.

Methods and Results

The study population included 557 consecutive patients with ACS for whom data were collected during emergency cardiac catheterization. To determine the possible impact of body mass index (BMI) on the relationship between left ventricular ejection fraction (LVEF) and plasma B-type NP (BNP) levels, the study population was divided into two groups (Group 1: BMI <25, Group 2: BMI ≥25 [kg/m2]). Both BMI and LVEF were significantly and negatively correlated with BNP. Although a significant negative correlation between LVEF and BNP was observed in both groups, the regression line of Group 2 was significantly less steep than that of Group 1. Accordingly, BNP/LVEF ratio in Group 2, which indicates the extent of BNP increase in response to LVEF change, was significantly lower than that in Group 1.

Conclusions

Blunted increase in plasma BNP in response to cardiac hemodynamic stress during ACS attacks was observed in obese individuals. In addition to the relatively low plasma BNP levels at baseline in obese individuals, the blunted response of BNP elevation to ACS attacks may have important pathophysiological implications for hemodynamic regulation and myocardial energy metabolism.

Predictive biomarkers for the early detection and management of heart failure

Cardiovascular disease (CVD) is a serious public health concern whose incidence has been on a rise and is projected by the World Health Organization to be the leading global cause of mortality by 2030. Heart failure (HF) is a complicated syndrome resulting from various CVDs of heterogeneous etiologies and exhibits varying pathophysiology, including activation of inflammatory signaling cascade, apoptosis, fibrotic pathway, and neuro-humoral system, thereby leading to compromised cardiac function. During this process, several biomolecules involved in the onset and progression of HF are released into circulation. These circulating biomolecules could serve as unique biomarkers for the detection of subclinical changes and can be utilized for monitoring disease severity. Hence, it is imperative to identify these biomarkers to devise an early predictive strategy to stop the deterioration of cardiac function caused by these complex cellular events. Furthermore, measurement of multiple biomarkers allows clinicians to divide HF patients into sub-groups for treatment and management based on early health outcomes. The present article provides a comprehensive overview of current omics platform available for discovering biomarkers for HF management. Some of the existing and novel biomarkers for the early detection of HF with special reference to endothelial biology are also discussed.

Differential Associations of A-/B-Type Natriuretic Peptides With Cardiac Structure, Function, and Prognosis in Heart Failure

BACKGROUND

Natriuretic peptide (NP) elevations are prognostic in heart failure (HF), but relative atrial NP deficiency in acute HF has been suggested.

OBJECTIVES

The authors compared plasma concentrations and relative strength of associations of A- and B-type NPs with cardiac structure/function and clinical outcomes in HF.

METHODS

Midregional pro-atrial natriuretic peptide (MR-proANP), B-type natriuretic peptide (BNP), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were measured in patients with compensated HF in a prospective, multicenter study. The primary outcome was a composite of HF-hospitalization or all-cause mortality. Secondary outcomes included individual primary outcome components and cardiovascular admission.

RESULTS

Among 1,278 patients (age 60.1 ± 12.1 years, 82% men, left ventricular ejection fraction [LVEF] 34% ± 14%), median concentrations of MR-proANP were 990 pg/mL (Q1-Q3: 557-1,563 pg/mL), NT-proBNP 1,648 pg/mL (Q1-Q3: 652-3,960 pg/mL), and BNP 291 pg/mL (Q1-Q3: 103-777 pg/mL). No subpopulation with inappropriately low MR-proANP (relative to BNP/NT-proBNP) was observed. Clinical event rates were similar for biomarker tertiles. Increments in MR-proANP exhibited steeper associations with concurrent shifts in left ventricular size, diastolic indexes and LVEF than BNP/NT-proBNP at baseline and serially (P < 0.05), and lower odds of beneficial left ventricular reverse remodeling: OR: 0.35 (95% CI: 0.18-0.70). In single-biomarker models, MR-proANP(log10) was associated with the highest hazard (4 to 6 times) for each outcome. In multimarker models, independent associations were observed for the primary outcome (MR-proANP and NT-proBNP), HF-hospitalization and cardiovascular admission (MR-proANP only), and all-cause mortality (NT-proBNP only) (P < 0.05). The discriminative value of MR-proANP was superior to BNP/NT-proBNP (HF-hospitalization) and BNP (primary outcome) (P < 0.05).

CONCLUSIONS

MR-proANP was not inappropriately low relative to concurrent BNP/NT-proBNP values. Proportional increments in MR-proANP were more pronounced than for B-peptides for given decrements in cardiac structure/function. MR-proANP offered greater independent predictive power overall.

Switching of hypertrophic signalling towards enhanced cardiomyocyte identity and maturity by a GATA4-targeted compound

BACKGROUND

The prevalence of heart failure is constantly increasing, and the prognosis of patients remains poor. New treatment strategies to preserve cardiac function and limit cardiac hypertrophy are therefore urgently needed. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are increasingly used as an experimental platform for cardiac in vitro studies. However, in contrast to adult cardiomyocytes, hiPSC-CMs display immature morphology, contractility, gene expression and metabolism and hence express a naive phenotype that resembles more of a foetal cardiomyocyte.

METHODS

A library of 14 novel compounds was synthesized in-house and screened for GATA4-NKX2-5 reporter activity and cellular toxicity. The most potent compound, 3i-1262, along with previously reported GATA4-acting compounds, were selected to investigate their effects on hypertrophy induced by endothelin-1 or mechanical stretch. Morphological changes and protein expression were characterized using immunofluorescence staining and high-content analysis. Changes in gene expression were studied using qPCR and RNA sequencing.

RESULTS

The prototype compound 3i-1262 inhibited GATA4-NKX2-5 synergy in a luciferase reporter assay. Additionally, the isoxazole compound 3i-1262 inhibited the hypertrophy biomarker B-type natriuretic peptide (BNP) by reducing BNP promoter activity and proBNP expression in neonatal rat ventricular myocytes and hiPSC-CMs, respectively. Treatment with 3i-1262 increased metabolic activity and cardiac troponin T expression in hiPSC-CMs without affecting GATA4 protein levels. RNA sequencing analysis revealed that 3i-1262 induces gene expression related to metabolic activity and cell cycle exit, indicating a change in the identity and maturity status of hiPSC-CMs. The biological processes that were enriched in upregulated genes in response to 3i-1262 were downregulated in response to mechanical stretch, and conversely, the downregulated processes in response to 3i-1262 were upregulated in response to mechanical stretch.

CONCLUSIONS

There is currently a lack of systematic understanding of the molecular modulation and control of hiPSC-CM maturation. In this study, we demonstrated that the GATA4-interfering compound 3i-1262 reorganizes the cardiac transcription factor network and converts hypertrophic signalling towards enhanced cardiomyocyte identity and maturity. This conceptually unique approach provides a novel structural scaffold for further development as a modality to promote cardiomyocyte specification and maturity.

Natriuretic peptides: Another tool for the management of cancer?

The connection between heart failure (HF) and cancer through multiple pathways such as inflammation, oxidative stress, and neurohormonal activation, among others, is well established. As a consequence, increases in plasma levels of several biomarkers have been described in both disorders. The most consistent information is related to natriuretic peptides (NPs). Although they are known to be produced in the ventricles as a response to myocardial distension, and thus can be useful for the diagnosis and prognosis of HF, and also for the management of chemotherapy-induced myocardial damage, they are also produced by tumour cells. In this regard, increased plasma levels of NPs have been described in patients with multiple malignancies in the absence of volume overload. Natriuretic peptide levels have been shown to correlate directly with the extension of tumours and with poorer outcomes. Moreover, some data indicate that they may help in the detection of subclinical tumours. Given that these peptides have been described to have anti-proliferative and anti-angiogenic effects, a plausible hypothesis is that they may be produced by tumours as a negative feed-back mechanism to avoid tumour progression. This would lead to increased levels of NPs in plasma that could be potentially useful for early detection of malignancies as well as for a prognostic assessment. Nevertheless, since the sample size of many studies published so far is limited, more data are needed to provide consistent data in order to confirm or rule out this hypothesis.

Do Heart Failure Biomarkers Influence Heart Failure Treatment Response?

PURPOSE OF REVIEW

Heart failure (HF) is one of the leading causes of cardiac morbidity and mortality around the world. Our evolving understanding of the cellular and molecular pathways of HF has led to the identification and evaluation of a growing number of HF biomarkers. Natriuretic peptides remain the best studied and understood HF biomarkers, with demonstrated clinical utility in the diagnosis and prognostication of HF. Less commonly understood is the utility of HF biomarkers for guiding and monitoring treatment response. In this review, we outline the current HF biomarker landscape and identify novel biomarkers that have potential to influence HF treatment response.

RECENT FINDINGS

An increasing number of biomarkers have been identified through the study of HF mechanisms. While these biomarkers hold promise, they have not yet been proven to be effective in guiding HF therapy. A more developed understanding of HF mechanisms has resulted in an increased number of available pharmacologic HF therapies. In the past, biomarkers have been useful for the diagnosis and prognostication of HF. Future evaluation on their use to guide pharmacologic therapy is ongoing, and there is promise that biomarker-guided therapy will allow clinicians to begin personalizing treatment for their HF patients.

Correlation between non-invasive to invasive right-heart data in paediatric heart transplant patients

BACKGROUND

Paediatric studies have shown serum N-terminal pro b-type natriuretic peptide levels to be a valuable tool in the surveillance of myocardial function and an early biomarker for rejection in transplant patients. The correlation between low mean right atrial pressure and increased inferior vena cava collapsibility index is well studied in adults. Our study aims to assess correlation between non-invasive measurements (serum N-terminal pro b-type natriuretic peptide, inferior vena cava dimensions collapsibility, tricuspid regurgitation, and left ventricular remodelling index to invasive mean right atrial pressure in paediatric heart transplant patients).

METHODS

A single centre, retrospective chart review of the paediatric transplant patients from 0 to 21 years of age was performed between 2015 and 2017. Thirty-nine patients had complete data which includes cardiac catheterisation, transthoracic echocardiogram, and serum N-terminal pro b-type natriuretic peptide levels done within a two weeks of interval.

RESULTS

A higher inferior vena cava collapsibility index correlated with a lower mean right atrial pressure (r = -0.21, p = 0.04) and a larger inferior vena cava diameter in expiration indexed to body surface area (IVCmax/BSA0.5) correlated with a higher mean right atrial pressure (r = 0.29, p = 0.01). There was a correlation between elevated N-terminal pro b-type natriuretic peptide and inferior vena cava collapsibility index (r = -0.38, p = 0.0001), IVCmax/BSA0.5 (r = 0.25, p = 0.0002), and mean right atrial pressure (r = 0.6, p = 0.0001).

CONCLUSION

Serum N-terminal pro b-type natriuretic peptide levels correlated to non-invasive measurements (inferior vena cava collapsibility index and IVCmax/BSA0.5) and to the invasive mean right atrial pressure. Non-invasive (IVC-CI IVCmax/BSA0.5) correlates with elevated mean right atrial pressure in this population. Together, these may serve as a reliable surveillance tool in assessing right heart filling pressures and cardiac function within the paediatric heart transplant patient.

Multiple Biomarkers to Predict Major Adverse Cardiovascular Events in Patients With Coronary Chronic Total Occlusions

Background

There are limited tools available to predict the long-term prognosis of persons with coronary chronic total occlusions (CTO).

Objectives

We evaluated performance of a blood biomarker panel to predict cardiovascular (CV) events in patients with CTO.

Methods

From 1251 patients in the CASABLANCA study, 241 participants with a CTO were followed for an average of 4 years for occurrence of major adverse CV events (MACE, CV death, non-fatal myocardial infarction or stroke) and CV death/heart failure (HF) hospitalization. Results of a biomarker panel (kidney injury molecule-1, N-terminal pro-B-type natriuretic peptide, osteopontin, and tissue inhibitor of metalloproteinase-1) from baseline samples were expressed as low-, moderate-, and high-risk.

Results

By 4 years, a total of 67 (27.8%) MACE events and 56 (23.2%) CV death/HF hospitalization events occurred. The C-statistic of the panel for MACE through 4 years was 0.79. Considering patients in the low-risk group as a reference, the hazard ratio of MACE by 4 years was 6.65 (95% confidence interval [CI]: 2.98-14.8) and 12.4 (95% CI:5.17-29.6) for the moderate and high-risk groups (both P <0.001). The C-statistic for CVD/HF hospitalization by 4 years was 0.84. Compared to the low-risk score group, the moderate and high-risk groups had hazard ratios of 5.61 (95% CI: 2.33-13.5) and 15.6 (95% CI: 6.18, 39.2; both P value <0.001).

Conclusion

A multiple biomarker panel assists in evaluating the risk of adverse outcomes in patients with coronary CTO. These results may have implications for patient care and could have a role for clinical trial enrichment.

Clinical Trial

CASABLANCA, ClinicalTrials.gov Identifier: NCT00842868.

BNP protects against diabetic cardiomyopathy by promoting Opa1-mediated mitochondrial fusion via activating the PKG-STAT3 pathway

Brain natriuretic peptide (BNP) belongs to the family of natriuretic peptides, which are responsible for a wide range of actions. Diabetic cardiomyopathy (DCM) is often associated with increased BNP levels. This present research intends to explore the role of BNP in the development of DCM and the underlying mechanisms. Diabetes was induced in mice using streptozotocin (STZ). Primary neonatal cardiomyocytes were treated with high glucose. It was found that the levels of plasma BNP started to increase at 8 weeks after diabetes, which preceded the development of DCM. Addition of exogenous BNP promoted Opa1-mediated mitochondrial fusion, inhibited mitochondrial oxidative stress, preserved mitochondrial respiratory capacity and prevented the development of DCM, while knockdown of endogenous BNP exacerbated mitochondrial dysfunction and accelerated DCM. Opa1 knockdown attenuated the aforementioned protective action of BNP both in vivo and in vitro. BNP-induced mitochondrial fusion requires the activation of STAT3, which facilitated Opa1 transcription by binding to its promoter regions. PKG, a crucial signaling biomolecule in the BNP signaling pathway, interacted with STAT3 and induced its activation. Knockdown of NPRA (the receptor of BNP) or PKG blunted the promoting effect of BNP on STAT3 phosphorylation and Opa1-mediated mitochondrial fusion. The results of this study demonstrate for the first time that there is a rise in BNP during the early stages of DCM as a compensatory protection mechanism. BNP is a novel mitochondrial fusion activator in protecting against hyperglycemia-induced mitochondrial oxidative injury and DCM through the activation of NPRA-PKG-STAT3-Opa1 signaling pathway.

Prospective Observational Study of N-terminal Pro-Brain Natriuretic Peptide Levels in Obese and Nonobese Women during Pregnancy

OBJECTIVE

N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of ventricular dysfunction, varies by body mass index (BMI) outside of pregnancy. This study aimed to determine whether obesity affects NT-proBNP levels in pregnancy.

STUDY DESIGN

This was a prospective observational study of healthy pregnant people in the third trimester (3TM) and postpartum (PP). Patients were excluded if they had significant medical comorbidities or if their fetuses had anomalies, growth restriction or aneuploidy. NT-proBNP was measured at 28 weeks (3TM), predelivery (PD), 1 to 2 days PP (immediate postpartum [IPP]), and 4 to 6 weeks PP (delayed postpartum [DPP]). LogNT-proBNP levels were analyzed using linear mixed effects models, including BMI < or ≥30, time, and time-by-BMI interactions.

RESULTS

Fifty-five people (28 [51%] with BMI ≥ 30 and 27 [49%] with BMI < 30) were enrolled. A greater proportion of obese than nonobese subjects developed hypertensive disorders of pregnancy (50 vs. 15%, p = 0.010) and obese patients had higher systolic blood pressures at all time points (p < 0.05). NT-proBNP levels (median [interquartile range] in pg/mL) were 18 (6-28) versus 26 (17-48) at 3TM, 16 (3-38) versus 43 (21-60) at PD, 58 (20-102) versus 63 (38-155) at IPP, and 33 (27-56) versus 23 (8-42) at DPP for obese compared with nonobese patients. In linear mixed effects models, logNT-proBNP was lower in obese patients at 3TM (β = -0.89 [95% confidence interval, CI: -1.51, -0.26]) and PD (β = -1.05 [95% CI: -1.72, -0.38]). The logNT-proBNP trends over time differed by BMI category, with higher values in obese patients at both PP time points compared with the 3TM (IPP β = 1.24 [95% CI: 0.75, 1.73]; DPP β = 1.08 [95% CI: 0.52, 1.63]), but only IPP for nonobese patients (β = 0.87 [95% CI: 0.36, 1.38]).

CONCLUSION

Obese patients had lower NT-proBNP levels than nonobese patients during pregnancy but not PP. The prolonged PP elevation in NT-proBNP in obese patients suggests that their PP cardiac recovery may be more prolonged.

KEY POINTS

· NT-proBNP levels are lower in obese than nonobese patients during pregnancy.. · Levels remain elevated in obese, but not nonobese, patients up to 4 to 6 weeks' postpartum.. · A lower threshold for concern regarding NT-proBNP levels may be needed in obese pregnant people..

Inhibition of Ceramide Synthesis Attenuates Chronic Ethanol Induced Cardiotoxicity by Restoring Lysosomal Function and Reducing Necroptosis

AIMS

Chronic alcohol misuse could cause alcoholic cardiomyopathy (ACM), and the specific mechanisms remained largely unknown. In this study, we aimed to explore the effects of endogenous ceramides on chronic ethanol-induced myocardial injury or cell loss (e.g. necroptosis).

METHODS

We established chronic alcohol intoxication models in vivo (male C57BL/6 mice) and in vitro (H9c2 cardiomyoblasts). The ceramide profiles were analyzed in mice myocardium and cultured cardiomyocytes. Further research on the role of ceramides and underlying signaling pathways was carried out in H9c2 cells.

RESULTS AND CONCLUSIONS

The ceramide profiles analysis revealed increased long and very long-chain ceramides in alcoholic myocardium and ethanol-treated cardiomyocytes. Next, we proved that endogenous ceramide inhibition could reduce necroptosis and alleviate cardiomyocytes injury as suggested by decreased levels of p-RIPK1, p-RIPK3 and p-MLKL proteins and cardiac injury factors expression. Furthermore, we found that lysosomal dysfunction also contributed to alcohol-induced cardiac damage and inhibiting ceramide biosynthesis could repaired this to some extent. Cells studies with exogenous C6 ceramide confirmed the pleotropic roles of ceramide in myocardial damage by causing both necroptosis and lysosomal dysfunction. Finally, our data suggested that lysosomal dysfunction could sensitize cardiomyocytes to induction of necroptosis due to the restriction on degradation of RIPK1/RIPK3 proteins. In conclusion, chronic ethanol treatment boosted myocardial ceramide synthesis in animal hearts and cultured cardiomyocytes. Moreover, ceramides exerted crucial roles in the intrinsic signaling pathways of alcohol-induced cardiotoxicity. Targeting ceramide biosynthesis to simultaneously attenuate necroptosis and lysosomal dysfunction might be a novel strategy for preventing alcoholic cardiotoxicity.

Cardiac Dysfunction Biomarkers Are Associated With Potential for Successful Separation From Extracorporeal Membrane Oxygenation in Children

Biomarkers of cardiac dysfunction may aid in decision making about organ recovery and optimal timing of separation from extracorporeal membrane oxygenation (ECMO). We conducted a prospective observational study of children from 0 to <18 years who underwent ECMO between 7/2010 and 6/2015 in a single center. In this pilot study, we aimed to determine whether Suppression of tumorigenicity 2 (ST2), N -terminal pro-B-type natriuretic peptide (NT-proBNP), galectin-3, and endostatin were associated with ability to separate from ECMO. Fifty neonatal and pediatric participants supported on venoarterial ECMO were included (median age 13 days, 50% male). Twelve (24%) participants were unable to separate from extracorporeal support. Plasma ST2 concentrations at cannulation were higher in children who were ultimately unable to separate versus those who successfully separated from ECMO (median 395.3 ng/mL vs. 207.4 ng/mL, p = 0.012). ST2 and NT-proBNP concentrations decreased significantly from the first to the last ECMO day in patients successfully separated from ECMO ( p < 0.0001 and p = 0.017, respectively). Endostatin concentrations increased significantly from the first to the last ECMO day in both groups. Galectin-3 concentrations were not associated with the ability to separate from ECMO. Cardiac dysfunction biomarkers, particularly ST2, may aid in decannulation decision-making in pediatric ECMO patients. These results should be validated with a larger study.

Prognostic Value of Admission Peak NT-proBNP Combined with Culprit Plaque Types for Predicting Cardiovascular Risk in ST-Segment Elevated Myocardial Infarction: An Optical Coherence Tomography Study

OBJECTIVE

Different culprit plaque phenotypes including plaque rupture (PR) and non-plaque rupture (NPR), and N-Terminal prohormone of brain natriuretic peptide (NT-proBNP) have been reported to influence clinical outcomes in patients with acute coronary syndrome (ACS). We aimed to investigate the prognostic implication of the peak and baseline values at admission for NT-proBNP for major adverse cardiovascular events (MACE) in ST-Segment Elevated Myocardial Infarction (STEMI) patients with different plaque phenotype.

METHODS

A total of 428 patients with STEMI undergoing optical coherence tomography (OCT) were enrolled and divided into four groups: PR/Tertile1-2 NT-proBNP (n = 132), PR/Tertile3 NT-proBNP (n = 65), NPR/Tertile1-2 NT-proBNP (n = 154), NPR/Tertlie3 NT-proBNP (n = 77). Baseline and Peak values of NT-proBNP were obtained in the admission period. The MACEs were defined as the composite of all-cause death, recurrence of myocardial infarction and stroke.

RESULTS

High levels for peak NT-proBNP were significantly associated with a higher incidence of MACE and death (Log rank p = 0.037 and 0.0012, respectively). In the subgroup with NPR, a high level for peak NT-proBNP was significantly associated with higher incidence of death (Log rank p = 0.0022) but this association was not significant in the subgroup of PR (Log rank p = 0.24). Though plaque types were not associated with adverse event, the combination of NPR and a higher peak value for NT-proBNP indicated higher incidence of death compared with other groups (Log rank p = 0.0017). The area under the receiver operating characteristic curve for predicting death to evaluate the diagnostic value of the peak value for NT-proBNP and plaque types combined with traditional risk factors was 0.843 (95% CI: 0.805-0.876), which is superior to solely traditional risk factors: NRI (26.8% [95% CI: 0.4-53.1%], p = 0.046) and IDI (5.1% [95% CI: 1.0-9.2%], p = 0.016).

CONCLUSION

STEMI patients with NPR and a high level for peak NT-proBNP showed higher incidence of death. The peak value of NT-proBNP in combination with plaque types can be used in risk stratification and prediction of death in patients with STEMI.

A Pathophysiological Approach To Current Biomarkers

Biomarkers are necessary for screening and diagnosing numerous diseases, predicting the prognosis of patients, and following-up treatment and the course of the patient. Everyday new biomarkers are being used in clinics for these purposes. This section will discuss the physiological roles of the various current biomarkers in a healthy person and the pathophysiological mechanisms underlying the release of these biomarkers. This chapter aims to gain a new perspective for evaluating and interpreting the most current biomarkers.

NRSF/REST-Mediated Epigenomic Regulation in the Heart: Transcriptional Control of Natriuretic Peptides and Beyond

Reactivation of fetal cardiac genes, including those encoding atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), is a key feature of pathological cardiac remodeling and heart failure. Intensive studies on the regulation of ANP and BNP have revealed the involvement of numerous transcriptional factors in the regulation of the fetal cardiac gene program. Among these, we identified that a transcriptional repressor, neuron-restrictive silencer factor (NRSF), also named repressor element-1-silencing transcription factor (REST), which was initially detected as a transcriptional repressor of neuron-specific genes in non-neuronal cells, plays a pivotal role in the transcriptional regulation of ANP, BNP and other fetal cardiac genes. Here we review the transcriptional regulation of ANP and BNP gene expression and the role of the NRSF repressor complex in the regulation of cardiac gene expression and the maintenance of cardiac homeostasis.

B-Type Natriuretic Peptide (BNP) Revisited—Is BNP Still a Biomarker for Heart Failure in the Angiotensin Receptor/Neprilysin Inhibitor Era?

Simple Summary

Active BNP-32, less active proBNP-108, and inactive N-terminal proBNP-76 all circulate in the blood. The circulating protease neprilysin has lower substrate specificity for BNP than ANP, while proBNP and N-terminal proBNP are not degraded by neprilysin. Currently available BNP immunoassays react with both mature BNP and proBNP; therefore, measured plasma BNP is mature BNP + proBNP. Because ARNI administration increases mature BNP, measured plasma BNP initially increases with ARNI administration by the amount of the increase in mature BNP. Later, ARNI administration reduces myocardial wall stress, and the resultant reduction in BNP production more than offsets the increase of mature BNP due to inhibition of degradation by neprilysin, resulting in lower plasma BNP levels. In the ARNI era, BNP remains a useful biomarker for heart failure, though mild increases early during ARNI administration should be taken into consideration.

Abstract

Myocardial wall stress, cytokines, hormones, and ischemia all stimulate B-type (or brain) natriuretic peptide (BNP) gene expression. Within the myocardium, ProBNP-108, a BNP precursor, undergoes glycosylation, after which a portion is cleaved by furin into mature BNP-32 and N-terminal proBNP-76, depending on the glycosylation status. As a result, active BNP, less active proBNP, and inactive N-terminal proBNP all circulate in the blood. There are three major pathways for BNP clearance: (1) cellular internalization via natriuretic peptide receptor (NPR)-A and NPR-C; (2) degradation by proteases in the blood, including neprilysin, dipeptidyl-peptidase-IV, insulin degrading enzyme, etc.; and (3) excretion in the urine. Because neprilysin has lower substrate specificity for BNP than atrial natriuretic peptide (ANP), the increase in plasma BNP after angiotensin receptor neprilysin inhibitor (ARNI) administration is much smaller than the increase in plasma ANP. Currently available BNP immunoassays react with both mature BNP and proBNP. Therefore, BNP measured with an immunoassay is mature BNP + proBNP. ARNI administration increases mature BNP but not proBNP, as the latter is not degraded by neprilysin. Consequently, measured plasma BNP initially increases with ARNI administration by the amount of the increase in mature BNP. Later, ARNI reduces myocardial wall stress, and the resultant reduction in BNP production more than offsets the increase in mature BNP mediated by inhibiting degradation by neprilysin, which lowers plasma BNP levels. These results suggest that even in the ARNI era, BNP can be used for diagnosis and assessment of the pathophysiology and prognosis of heart failure, though the mild increases early during ARNI administration should be taken into consideration.

Higher BNP/NT-pro BNP levels stratify prognosis equally well in patients with and without heart failure: a meta-analysis

AIMS

The initial and dynamic levels of B-type natriuretic peptide (BNP) and N-terminal-prohormone BNP (NT-proBNP) are routinely used in clinical practice to identify patients with acute and chronic heart failure. In addition, BNP/NT-proBNP levels might be useful for risk stratification in patients with and without heart failure. We performed a meta-analysis to investigate, whether the value of BNP/NT-proBNP as predictors of long-term prognosis differentiates in cohorts with and without heart failure.

METHODS AND RESULTS

We systematically searched established scientific databases for studies evaluating the prognostic value of BNP or NT-proBNP. Random effect models were constructed. Data from 66 studies with overall 83 846 patients (38 studies with 46 099 patients with heart failure and 28 studies with 37 747 patients without heart failure) were included. In the analysis of the log-transformed BNP/NT-proBNP levels, an increase in natriuretic peptides by one standard deviation was associated with a 1.7-fold higher MACE rate (hazard ratio [95% confidence interval]: 1.74[1.58-1.91], P < 0.0001). The effect sizes were comparable, with a substantial overlap in the confidence intervals, when comparing studies involving patients with and without heart failure (1.75[1.54-2.0], P < 0.0001 vs. 1.74[1.47-2.06], P < 0.0001). Similar results were observed when stratifying by quartiles of BNP/NT-proBNP. In studies using pre-defined cut-off-values for BNP/NT-proBNP, elevated levels were associated with the long-term prognosis, independent of the specific cut-off value used.

CONCLUSIONS

BNP/NT-proBNP levels are predictors for adverse long-term outcome in patients with and without known heart failure. Further research is necessary to establish appropriate thresholds, especially in non-heart failure cohorts.

Cardiovascular Biomarkers: Lessons of the Past and Prospects for the Future

Cardiovascular diseases (CVDs) are a major healthcare burden on the population worldwide. Early detection of this disease is important in prevention and treatment to minimise morbidity and mortality. Biomarkers are a critical tool to either diagnose, screen, or provide prognostic information for pathological conditions. This review discusses the historical cardiac biomarkers used to detect these conditions, discussing their application and their limitations. Identification of new biomarkers have since replaced these and are now in use in routine clinical practice, but still do not detect all disease. Future cardiac biomarkers are showing promise in early studies, but further studies are required to show their value in improving detection of CVD above the current biomarkers. Additionally, the analytical platforms that would allow them to be adopted in healthcare are yet to be established. There is also the need to identify whether these biomarkers can be used for diagnostic, prognostic, or screening purposes, which will impact their implementation in routine clinical practice.

Global PIEZO1 Gain-of-Function Mutation Causes Cardiac Hypertrophy and Fibrosis in Mice

PIEZO1 is a subunit of mechanically-activated, nonselective cation channels. Gain-of-function PIEZO1 mutations are associated with dehydrated hereditary stomatocytosis (DHS), a type of anaemia, due to abnormal red blood cell function. Here, we hypothesised additional effects on the heart. Consistent with this hypothesis, mice engineered to contain the M2241R mutation in PIEZO1 to mimic a DHS mutation had increased cardiac mass and interventricular septum thickness at 8–12 weeks of age, without altered cardiac contractility. Myocyte size was greater and there was increased expression of genes associated with cardiac hypertrophy (Anp, Acta1 and β-MHC). There was also cardiac fibrosis, increased expression of Col3a1 (a gene associated with fibrosis) and increased responses of isolated cardiac fibroblasts to PIEZO1 agonism. The data suggest detrimental effects of excess PIEZO1 activity on the heart, mediated in part by amplified PIEZO1 function in cardiac fibroblasts.

Transcriptomic Response in the Heart and Kidney to Different Types of Antihypertensive Drug Administration

Certain classes of antihypertensive drug may exert specific, blood pressure (BP)-independent protective effects on end-organ damages such as left ventricular hypertrophy, although the overall evidence has not been definitive in clinical trials. To unravel antihypertensive drug-induced gene expression changes that are potentially related to the amelioration of end-organ damages, we performed in vivo phenotypic evaluation and transcriptomic analysis on the heart and the kidney, with administration of antihypertensive drugs to two inbred strains (ie, hypertensive and normotensive) of rats. We chose 6 antihypertensive classes: enalapril (angiotensin-converting enzyme inhibitor), candesartan (angiotensin receptor blocker), hydrochlorothiazide (diuretics), amlodipine (calcium-channel blocker), carvedilol (vasodilating β-blocker), and hydralazine. In the tested rat strains, 4 of 6 drugs, including 2 renin-angiotensin system inhibitors, were effective for BP lowering, whereas the remaining 2 drugs were not. Besides BP lowering, there appeared to be some interdrug heterogeneity in phenotypic changes, such as suppressed body weight gain and body weight-adjusted heart weight reduction. For the transcriptomic response, a considerable number of genes showed prominent mRNA expression changes either in a BP-dependent or BP-independent manner with substantial diversity between the target organs. Noticeable changes of mRNA expression were induced particularly by renin-angiotensin system blockade, for example, for genes in the natriuretic peptide system (Nppb and Corin) in the heart and for those in the renin-angiotensin system/kallikrein-kinin system (Ren and rat Klk1 paralogs) and those related to calcium ion binding (Calb1 and Slc8a1) in the kidney. The research resources constructed here will help corroborate occasionally inconclusive evidence in clinical settings.

Characterisation of the single-cell human cardiomyocytes taken from the excess heart tissue of the right ventricular outlet in congenital heart disease

Cardiovascular disease is the second highest cause of death across the globe. Myocardial infarction is one of the heart diseases that cause permanent impairment of the heart wall leads to heart failure. Cellular therapy might give hope to regenerate the damaged myocardium. Single cells isolated from an excess heart tissue obtained from the correction of the right ventricular hypertrophy in patients with Tetralogy of Fallot for future heart study were investigated.

METHODS

Once resected, the heart tissues were transported at 37 °C, in Dulbecco's Modified Eagle's medium/ DMEM (4.5 g.L^-1, antibiotic-antimycotic 3x, PRP10% (v/v)), to reach the lab within 30 min, weighted and grouped into less than 500 mg and more than 1000 mg (n = 4). Each sample was digested with 250 U.mL^-1 Collagenase type V and 4U.mL^-1 Proteinase XXIV in the MACS™ C-tube (Milltenyi, Germany), then dissociated using the MACS™ Octo Dissociator with Heater (Milltenyi, Germany) for 60 min at 37 °C.

RESULTS

All cells isolated were rod-shaped cells; viability was up to 90%. The cell density obtained from the 500 mg group were 4,867 ± 899 cells.mg^-1 tissue weight, significantly higher compared to the 1,000 mg group; had 557 ± 490 cells.mg^-1 tissue weight (mean of (n = 3) ± 95% C.l). The isolated cells were analyzed using FACs BD Flowcytometer, expressed cTnT + 13.38%, PECAM-1 + /VCAM-1- 32.25%, cKit + 7.85%, ICAM + 85.53%, indicating the cardiomyocyte progenitor cells.

CONCLUSION

Cardiomyocytes taken from the wasted heart tissue might be a candidate of cardiomyocytes source to study interventions to the heart as it contained up to 13.38% cardiomyocytes, and 32.25% of cardiac progenitor cells. Moreover, perhaps when cardiac cell therapy needs autologous cardiomyocytes, less than 500 mg tissue weight can be considered as sufficient.

Biomarkers for oxidative stress and organ injury during Transnasal Humidified Rapid-Insufflation Ventilatory Exchange compared to mechanical ventilation in adults undergoing microlaryngoscopy: A randomised controlled study

BACKGROUND

Apnoeic oxygenation using Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) during general anaesthesia prolongs the safe apnoeic period. However, there is a gap of knowledge how THRIVE-induced hyperoxia and hypercapnia impact vital organs. The primary aim of this randomised controlled trial was to characterise oxidative stress and, secondary, vital organ function biomarkers during THRIVE compared to mechanical ventilation (MV).

METHODS

Thirty adult patients, American Society of Anesthesiologists (ASA) 1-2, undergoing short laryngeal surgery under general anaesthesia were randomised to THRIVE, F_I O₂ 1.0, 70 L min^-1 during apnoea or MV. Blood biomarkers for oxidative stress, malondialdehyde and TAC and vital organ function were collected (A) preoperatively, (B) at procedure completion and (C) at PACU discharge.

RESULTS

Mean apnoea time was 17.9 (4.8) min and intubation to end-of-surgery time was 28.1 (12.8) min in the THRIVE and MV group, respectively. Malondialdehyde increased from 11.2 (3.1) to 12.7 (3.1) µM (P = .02) and from 9.5 (2.2) to 11.6 (2.6) µM (P = .003) (A to C) in the THRIVE and MV group, respectively. S100B increased from 0.05 (0.02) to 0.06 (0.02) µg L^-1 (P = .005) (A to C) in the THRIVE group. No increase in TAC, CRP, leukocyte count, troponin-T, NTproBNP, creatinine, eGFRcrea or NSE was demonstrated during THRIVE.

CONCLUSION

While THRIVE and MV was associated with increased oxidative stress, we found no change in cardiac, inflammation or kidney biomarkers during THRIVE. Further evaluation of stress and inflammatory response and cerebral and cardiac function during THRIVE is needed.

NT-proBNP/BNP ratio for prognostication in European Caucasian patients enrolled in a heart failure prevention programme

Aims

Guidelines support the role of B‐type natriuretic peptide (BNP) and amino‐terminal pro‐BNP (NT‐proBNP) for risk stratification of patients in programmes to prevent heart failure (HF). Although biologically formed in a 1:1 ratio, the ratio of NT‐proBNP to BNP exhibits wide inter‐individual variability. A report on an Asian population suggests that molar NT‐proBNP/BNP ratio is associated with incident HF. This study aims to determine whether routine, simultaneous evaluation of both BNP and NT‐proBNP is warranted in a European, Caucasian population.

Methods and Results

We determined BNP and NT‐proBNP levels for 782 Stage A/B HF patients in the STOP‐HF programme. The clinical, echocardiographic, and biochemical associates of molar NT‐proBNP/BNP ratio were analysed. The primary endpoint was the adjusted association of baseline molar NT‐proBNP/BNP ratio with new‐onset HF and/or progression of left ventricular dysfunction (LVD). We estimated the C‐statistic, integrated discrimination improvement, and the category‐free net reclassification improvement metric for the addition of molar NT‐proBNP/BNP ratio to adjusted models. The median age was 66.6 years [interquartile range (IQR) 59.5–73.1], 371 (47.4%) were female, and median molar NT‐proBNP/BNP ratio was 1.91 (IQR 1.37–2.93). Estimated glomerular filtration rate, systolic blood pressure, left ventricular mass index, and heart rate were associated with NT‐proBNP/BNP ratio in a linear regression model (all P < 0.05). Over a median follow‐up period of 5 years (IQR 3.4–6.8), 247 (31.5%) patients developed HF or progression of LVD. Log‐transformed NT‐proBNP/BNP ratio is inversely associated with HF and LVD risk when adjusted for age, gender, diabetes, hypertension, vascular disease, obesity, heart rate, number of years of follow‐up, estimated glomerular filtration rate, and baseline NT‐proBNP (odds ratio 0.71, 95% confidence interval 0.55–0.91; P = 0.008). However, molar NT‐proBNP/BNP ratio did not increase the C‐statistic (Δ −0.01) and net reclassification improvement (0.0035) for prediction of HF and LVD compared with NT‐proBNP or BNP alone. Substitution of NT‐proBNP for BNP in the multivariable model eliminated the association with HF and LVD risk.

Conclusions

This study characterized, for the first time in a Caucasian Stage A/B HF population, the relationship between NT‐proBNP/BNP ratio and biological factors and demonstrated an inverse relationship with the future development of HF and LVD. However, this study does not support routine simultaneous BNP and NT‐proBNP measurement in HF prevention programmes amongst European, Caucasian patients.

Comparison of High-Sensitive CRP, RDW, PLR and NLR between Patients with Chronic Obstructive Pulmonary Disease and Chronic Heart Failure

Background:

Chronic obstructive pulmonary disease (COPD) is a chronic systemic inflammation, which has similar signs and symptoms to chronic heart failure (CHF).

Objective:

To compare high-sensitive C-reactive protein (hsCRP) level and selected blood indices in patients with COPD and CHF.

Methods:

This prospective cross-sectional study (July 2019-July 2020) was conducted on patients aged 40-70 years old with a previous diagnosis of COPD, CHF, and cor pulmonale. They were divided into four groups: 1) patients with COPD, who were hospitalized due to exacerbation of dyspnea, 2) patients with CHF without a history of COPD, 3) patients with CHF and history of COPD (COPD+CHF), and finally 4) patients who had concomitant COPD and cor pulmonale condition. Spirometry, echocardiography, and six-minute walking test were performed. The hsCRP level was assessed at the beginning and end of hospital admission. Finally, RDW, neutrophil, lymphocyte, platelet counts, neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR) were measured. Data were analyzed by SPSS software (α = 0.05).

Results:

In total, 140 patients were enrolled. The highest hsCRP level was observed in patients in the COPD+CHF group, and the lowest level was found in patients with CHF. Overall, a significant difference was observed in the hsCRP level at the beginning and the end of admission (P =0.0001). HsCRP had a positive correlation with the duration of hospital stay and a negative correlation with the results of the six-minute walking test. The lymphocyte counts and PLR had significant positive correlations with the six-minute walking test (R =0.38, P =0.0001 vs. R =0.325, P =0.001, respectively), and significant negative correlations with duration of hospital stay (R =-0.317, P =0.0001 vs. R =-0.380, P =0.001, respectively). At the admission, a significant difference in hsCRP was only observed comparing the COPD and cor pulmonale groups (OR =1.097, P =0.002). There were significant differences in the six-minute walking test comparing the COPD group with either of CHF or COPD+CHF groups. Significant differences were noted in the hospital stay duration comparing the COPD group with all other groups.

Neurohormones, inflammatory mediators, and cardiovascular injury in the setting of heart failure

Neurohormones and inflammatory mediators have effects in both the heart and the peripheral vasculature. In patients with heart failure (HF), neurohormonal activation and increased levels of inflammatory mediators promote ventricular remodeling and development of HF, as well as vascular dysfunction and arterial stiffness. These processes may lead to a vicious cycle, whereby arterial stiffness perpetuates further ventricular remodeling leading to exacerbation of symptoms. Although significant advances have been made in the treatment of HF, currently available treatment strategies slow, but do not halt, this cycle. The current treatment for HF patients involves the inhibition of neurohormonal activation, which can reduce morbidity and mortality related to this condition. Beyond benefits associated with neurohormonal blockade, other strategies have focused on inhibition of inflammatory pathways implicated in the pathogenesis of HF. Unfortunately, attempts to target inflammation have not yet been successful to improve prognosis of HF. Further work is required to interrupt key maladaptive mechanisms involved in disease progression.

The natriuretic peptide system in heart failure: Diagnostic and therapeutic implications

Natriuretic peptides, which are activated in heart failure, play an important cardioprotective role. The most notable of the cardioprotective natriuretic peptides are atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), which are abundantly expressed and secreted in the atrium and ventricles, respectively, and C-type natriuretic peptide (CNP), which is expressed mainly in the vasculature, central nervous system, and bone. ANP and BNP exhibit antagonistic effects against angiotensin II via diuretic/natriuretic actions, vasodilatory actions, and inhibition of aldosterone secretion, whereas CNP is involved in the regulation of vascular tone and blood pressure, among other roles. ANP and BNP are of particular interest with respect to heart failure, as their levels, most notably BNP and N-terminal proBNP-a cleavage product produced when proBNP is processed to mature BNP-are increased in patients with heart failure. Furthermore, the identification of natriuretic peptides as sensitive markers of cardiac load has driven significant research into their physiological roles in cardiovascular homeostasis and disease, as well as their potential use as both biomarkers and therapeutics. In this review, I discuss the physiological functions of the natriuretic peptide family, with a particular focus on the basic research that has led to our current understanding of its roles in maintaining cardiovascular homeostasis, and the pathophysiological implications for the onset and progression of heart failure. The clinical significance and potential of natriuretic peptides as diagnostic and/or therapeutic agents are also discussed.

Physiological Changes, Activity, and Stress During a 100-km-24-h Walking-March

Background

Long-endurance exercises like ultramarathons are known to elicit various metabolic and physiological changes in the human body. However, little is known about very long-duration exercise at low intensities regarding healthy human subjects.

Aim

The purpose of this study was to evaluate changes in body composition and metabolism in long-endurance but low-intensity events.

Methods

Twenty-five male and 18 female healthy recreational athletes (age 34.6 ± 8.8 years; BMI: 22.4 ± 2.0 kg/m²) of the "100 km Mammutmarsch" were recruited for participation during the events in 2014-2016. Other than classical ultramarathons, the "Mammutmarsch" is a hiking event, in which participants were required to walk but not run or jog. It was expected to complete the 100-km distance within 24 h, resulting in a calculated mean speed of 4.17 km/h, which fits to the mean speed observed (4.12 ± 0.76 km/h). As not all participants reached the finish line, comparison of finishers (FIN, n = 11) and non-finishers (NON, n = 21) allowed differential assessment of performance. Body composition measured through bioelectrical impedance analysis (BIA) was determined pre- and post-event, and serum samples were taken pre-event, at 30, 70, and 100 km to determine NT-pro-BNP, troponin T, C-reactive protein (CRP), cortisol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, total cholesterol, total creatine kinase (CK), CK-MB, aminotransferase (AST), ALT, and sodium levels. Nineteen participants wore actimeter armbands (SenseWear^®) to gain information about body activity and exercise intensity [metabolic equivalent of task (MET)]. Sixteen participants wore mobile heart rate monitors to assess mean heart rate during the race. Serum parameter alterations over the course of the race were analyzed with mixed-effects ANOVA and additional t-tests. All serum parameters were analyzed for correlation concerning different MET levels, speed, age, BMI, baseline NT-pro-BNP, mean heart rate during the race, and sex with linear regression analysis.

Results

We found significant elevations for muscle and cardiac stress markers (CRP, CK, CK-MB, AST, ALT, cortisol, and NT-pro-BNP) as well as decreasing markers of lipid metabolism (cholesterol, triglycerides, LDL). Although the intensity level demanded from our participants was low compared with other studies on (ultra-) marathons, the alteration of tested parameters was similar to those of high-intensity exercise, e.g., NT-pro-BNP showed a fourfold increase (p < 0.01) and LDL decreased by 20% (p = 0.05). Besides the duration of exercise, age, BMI, training status, and sex are relevant parameters that influence the elevation of stress factors. Notably, our data indicate that NT-pro-BNP might be a marker for cardiovascular fitness also in healthy adults.

Conclusion

This low-intensity long-endurance walk evoked a strong systemic reaction and large cell stress and shifted to a favorable lipid profile, comparable to higher intensity events. Despite increasing cardiac stress parameters, there were no indications of cardiac cell damage. Remarkably, the duration seems to have a greater influence on stress markers and metabolism than intensity.

Epidemiology, Pathophysiology, Diagnosis and Treatment of Heart Failure in Diabetes

The cardiovascular disease continuum begins with risk factors such as diabetes mellitus (DM), progresses to vasculopathy and myocardial dysfunction, and finally ends with cardiovascular death. Diabetes is associated with a 2- to 4-fold increased risk for heart failure (HF). Moreover, HF patients with DM have a worse prognosis than those without DM. Diabetes can cause myocardial ischemia via micro- and macrovasculopathy and can directly exert deleterious effects on the myocardium. Hyperglycemia, hyperinsulinemia, and insulin resistance can cause alterations in vascular homeostasis. Then, reduced nitric oxide and increased reactive oxygen species levels favor inflammation leading to atherothrombotic progression and myocardial dysfunction. The classification, diagnosis, and treatment of HF for a patient with and without DM remain the same. Until now, drugs targeting neurohumoral and metabolic pathways improved mortality and morbidity in HF with reduced ejection fraction (HFrEF). Therefore, all HFrEF patients should receive guideline-directed medical therapy. By contrast, drugs modulating neurohumoral activity did not improve survival in HF with preserved ejection fraction (HFpEF) patients. Trials investigating whether sodium-glucose cotransporter-2 inhibitors are effective in HFpEF are on-going. This review will summarize the epidemiology, pathophysiology, and treatment of HF in diabetes.

Direct Actions of AT1 (Type 1 Angiotensin) Receptors in Cardiomyocytes Do Not Contribute to Cardiac Hypertrophy

Supplemental Digital Content is available in the text.

Activation of AT₁ (type 1 Ang) receptors stimulates cardiomyocyte hypertrophy in vitro. Accordingly, it has been suggested that regression of cardiac hypertrophy associated with renin-Ang system blockade is due to inhibition of cellular actions of Ang II in the heart, above and beyond their effects to reduce pressure overload. We generated 2 distinct mouse lines with cell-specific deletion of AT_1A receptors, from cardiomyocytes. In the first line (C-SMKO), elimination of AT_1A receptors was achieved using a heterologous Cre recombinase transgene under control of the Sm22 promoter, which expresses in cells of smooth muscle lineage including cardiomyocytes and vascular smooth muscle cells of conduit but not resistance vessels. The second line (R-SMKO) utilized a Cre transgene knocked-in to the Sm22 locus, which drives expression in cardiac myocytes and vascular smooth muscle cells in both conduit and resistance arteries. Thus, although both groups lack AT₁ receptors in the cardiomyocytes, they are distinguished by presence (C-SMKO) or absence (R-SMKO) of peripheral vascular responses to Ang II. Similar to wild-types, chronic Ang II infusion caused hypertension and cardiac hypertrophy in C-SMKO mice, whereas both hypertension and cardiac hypertrophy were reduced in R-SMKOs. Thus, despite the absence of AT_1A receptors in cardiomyocytes, C-SMKOs develop robust cardiac hypertrophy. By contrast, R-SMKOs developed identical levels of hypertrophy in response to pressure overload–induced by transverse aortic banding. Our findings suggest that direct activation of AT₁ receptors in cardiac myocytes has minimal influence on cardiac hypertrophy induced by renin-Ang system activation or pressure overload.

Mating-induced increase in Kiss1 mRNA expression in the anteroventral periventricular nucleus prior to an increase in LH and testosterone release in male rats

Kisspeptin has an indispensable role in gonadotropin-releasing hormone/gonadotropin secretion in mammals. In rodents, kisspeptin neurons are located in distinct brain regions, namely the anteroventral periventricular nucleus-periventricular nucleus continuum (AVPV/PeN), arcuate nucleus (ARC), and medial amygdala (MeA). Among them, the physiological role of AVPV/PeN kisspeptin neurons in males has not been clarified yet. The present study aims to investigate the acute effects of the olfactory and/or mating stimulus with a female rat on hypothalamic and MeA Kiss1 mRNA expression, plasma luteinizing hormone (LH) and testosterone levels in male rats. Intact male rats were exposed to the following stimuli: exposure to clean bedding; exposure to female-soiled bedding as a female-olfactory stimulus; exposure to female-soiled bedding and mating stimulus with a female rat. The mating stimulus significantly increased the number of the AVPV/PeN Kiss1 mRNA-expressing cells in males within 5 minutes after the exposure, and significantly increased LH and testosterone levels, followed by an increase in male sexual behavior. Whereas, the males exposed to female-soiled bedding showed a moderate increase in LH levels and no significant change in testosterone levels and the number of the AVPV/PeN Kiss1 mRNA-expressing cells. Importantly, none of the stimuli affected the number of Kiss1 mRNA-expressing cells in the ARC and MeA. These results suggest that the mating-induced increase in AVPV/PeN Kiss1 mRNA expression may be, at least partly, involved in stimulating LH and testosterone release, and might consequently ensure male mating behavior. This study would be the first report suggesting that the AVPV/PeN kisspeptin neurons in males may play a physiological role in ensuring male reproductive performance.

Takotsubo Syndrome: Cardiotoxic Stress in the COVID Era

Takotsubo syndrome (TTS), also known as stress cardiomyopathy and broken heart syndrome, is a neurocardiac condition that is among the most dramatic manifestations of psychosomatic disorders. This paper is based on a systematic review of TTS and stress cardiomyopathy using a PubMed literature search. Typically, an episode of severe emotional or physical stress precipitates regions of left ventricular hypokinesis or akinesis, which are not aligned with a coronary artery distribution and are out of proportion to the modest troponin leak. A classic patient with TTS is described; one who had chest pain and dyspnea while watching an anxiety-provoking evening news program on the coronavirus disease 2019 (COVID-19) pandemic. An increase in the incidence of TTS appears to be a consequence of the COVID-19 pandemic, with the TTS incidence rising 4.5-fold during the COVID-19 pandemic even in individuals without severe acute respiratory syndrome coronavirus 2 infection. Takotsubo syndrome is often mistaken for acute coronary syndrome because they both typically present with chest pain, electrocardiographic changes suggesting myocardial injury/ischemia, and troponin elevations. Recent studies report that the prognosis for TTS is similar to that for acute myocardial infarction. This review is an update on the mechanisms underlying TTS, its diagnosis, and its optimal management.

Functional analysis of the brain natriuretic peptide gene for high-altitude adaptation in Tibetan pigs

High-altitude adaptation in Tibetan pigs (TP) is associated with positively-selected genes. The brain natriuretic peptide (BNP) gene is critical in the regulation of cardiovascular homeostasis and energy metabolism. The present study was conducted to identify the function of BNP for high-altitude adaptations in TP. RT-qPCR and western blotting results indicated that BNP expression could be upregulated when the pigs (especially for the Tibetan pigs) were raised to high altitude. In the 5' flanking region, three polymorphic sites, A-1964G, C-1780G, and T-940C were detected, and the genotype distribution of C-1780G was significantly different between the highland (TP) and lowland (Diannan small-eared pig; Yorkshire pig) breeds. The site of C-1780G was in active promoter regions identified using the luciferase reporter gene system, and the fragment with allele G had higher transcriptional activity than that with allele C. The TP population had a higher frequency of allele G than the two lowland breeds. Our results collectively demonstrated that the G allele of C-1780G in the BNP gene may be advantageous for high-altitude adaptation in pigs through upregulating BNP expression. Our findings provide information that helps toward a comprehensive understanding of the mechanism underlying the involvement of the BNP gene in high-altitude adaptation.

Efficacy and safety of early ultrafiltration in patients with acute decompensated heart failure with volume overload: a prospective, randomized, controlled clinical trial

Background

Ultrafiltration decreases total body water and improves the alveolar to arterial oxygen gradient. The aims of the study were to investigate the efficacy and safety of early ultrafiltration in acute decompensated heart failure (ADHF) patients.

Methods

100 patients with ADHF within 24 h of admission were randomly assigned into early ultrafiltration (n = 40) or torasemide plus tolvaptan (n = 60) groups. The primary outcomes were weight loss and an increase in urine output on days 4 and 8 of treatment.

Results

Patients who received early ultrafiltration for 3 days achieved a greater weight loss (kg) (− 2.94 ± 3.76 vs − 0.64 ± 0.91, P < 0.001) and urine increase (mL) (198.00 ± 170.70 vs 61.77 ± 4.67, P < 0.001) than the torasemide plus tolvaptan group on day 4. From days 4 to 7, patients in the early ultrafiltration group received sequential therapy of torasemide and tolvaptan. Better control of volume was reflected in a greater weight loss (− 3.72 ± 3.81 vs − 1.34 ± 1.32, P < 0.001) and urine increase (373.80 ± 120.90 vs 79.5 ± 52.35, P < 0.001), greater reduction of B-type natriuretic peptide (BNP) (pg/mL) (− 1144 ± 1435 vs − 654.02 ± 889.65, P = 0.037), NYHA (New York Heart Association) functional class (− 1.45 ± 0.50 vs − 1.17 ± 0.62, P = 0.018), jugular venous pulse (JVP) score (points) (− 1.9 ± 1.13 vs − 0.78 ± 0.69, P < 0.001), inferior vena cava (IVC) diameter (mm) (− 15.35 ± 11.03 vs − 4.98 ± 6.00, P < 0.001) and an increase in the dyspnea score (points) (4.08 ± 3.44 vs 2.77 ± 2.03, P = 0.035) in the early ultrafiltration group on day 8. No significant differences were found in the readmission and mortality rates in the 2 patient groups at the 1-month and 3-month follow-ups. Both groups had a similar stable renal profile.

Conclusion

Early ultrafiltration is superior to diuretics for volume overload treatment initiation of ADHF patients.

Trial registration Chinese Clinical Trial Registry, ChiCTR2000030696, Registered 10 March 2020—Retrospectively registered, https://www.chictr.org.cn/showproj.aspx?proj=29099.

Single-cell Transcriptome Analysis Indicates New Potential Regulation Mechanism of ACE2 and NPs signaling among heart failure patients infected with SARS-CoV-2

BACKGROUND

COVID-19 patients with comorbidities such as hypertension or heart failure (HF) are associated with poor clinical outcomes. Angiotensin-converting enzyme 2 (ACE2), the critical enzyme for SARS-CoV-2 infection, is broadly expressed in many organs including heart. However, the cellular distribution of ACE2 in the human heart, particularly the failing heart is unknown.

METHODS

We analyzed single-cell RNA sequencing (scRNA-seq) data in both normal and failing hearts, and characterized the ACE2 gene expression profile in various cell subsets, especially in cardiomyocyte subsets, as well as its interaction with gene networks relating to various defense and immune responses at the single cell level.

RESULTS

The results demonstrated that ACE2 is present in cardiomyocytes (CMs), endothelial cells, fibroblasts and smooth muscle cells in the heart, while the number of ACE2-postive (ACE2+) CMs and ACE2 gene expression in these CMs are significantly increased in the failing hearts. Interestingly, both brain natriuretic peptides (BNP) and atrial natriuretic peptide (ANP) are significantly up-regulated in the ACE2+ CMs. Further analysis shows that ANP, BNP and ACE2 may form a negative feedback loop with a group of genes associated with the development of heart failure. To our surprise, we found that genes related to virus entry, virus replication and suppression of interferon-gamma（IFN-γ）signaling are all up-regulated in CMs in failing hearts, and the increases were significantly higher in ACE2+ CMs as compared with ACE2 negative (ACE2-) CMs, suggesting that these ACE2+ CMs may be more vulnerable to virus infection. Since ACE2 expression is correlated with BNP expression, we further performed retrospective analysis of the plasma BNP levels and clinic outcome of 91 COVID-19 patients from a single-center. Patients with higher plasma BNP were associated with significantly higher mortality rate and expression levels of inflammatory and infective markers such as procalcitonin and C-reactive protein.

CONCLUSION

In the failing heart, the upregulation of ACE2 and virus infection associated genes, as well as the increased expression of ANP and BNP could facilitate SARS-CoV-2 virus entry and replication in these vulnerable cardiomyocyte subsets. These findings may advance our understanding of the underlying molecular mechanisms of myocarditis associated with COVID-19.

[Possibilities of modern biomarkers for assessing the risk of developing ventricular tachyarrhythmias and sudden cardiac death in patients with chronic heart failure]

Current biomarkers allow diagnosing a wide array of pathological processes and evaluating effects of therapies and prognosis for cardiological patients. This review focuses on a possibility of using N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble suppressor of tumorigenicity 2 (sST2), galectin-3, and other biomarkers in patients with chronic heart failure for evaluating the risk of life-threatening ventricular tachyarrhythmias and sudden cardiac death.

Analyse biochimique multi-paramétrique révélant une augmentation de l'homocystéinémie et du NT-ProBNP chez les patients hypertendus à Bamako (Mali)

Introduction

L'hypertension artérielle est un problème majeur de santé publique en Afrique subsaharienne par sa fréquence élevée et le risque cardiovasculaire qu'elle entraine. L'objectif de cette étude était d'évaluer la prévalence des facteurs de risques cliniques et biologiques de l'hypertension artérielle à Bamako (Mali).

Méthodes

Il s'agit d'une étude cas-témoin, stratifiée en fonction du sexe, portant sur 72 participants dont 36 hypertendus et 36 contrôles. Vingt-deux paramètres biochimiques plasmatiques ont été mesurés et analysés par des tests univariés et multivariés.

Résultats

Une hyperhomocystéinémie a été retrouvée chez 55,6% des femmes (p = 0,03) et 100% des hommes (p = 0,007) hypertendus. Le N-terminal pro B-type natriuretic peptide (NT-Pro-BNP) était également augmenté chez 16,7% des femmes (VIP > 1 dans le modèle multivarié) et des hommes hypertendus (p = 0,00006). Un bon modèle multivarié prédictif (OPLS-DA) a uniquement été obtenu chez les femmes hypertendues, avec un Q²cum = 0,73, attestant ainsi d'un important dimorphisme sexuel associé à l'hypertension artérielle. Ce modèle impliquait huit paramètres dont la concentration plasmatique était modifiée (homocystéine, NT-Pro-BNP, potassium, urée, glycémie, sodium, chlore et protéines totales).

Conclusion

Nous avons noté une association significative entre l'hyperhomocystéinémie et l'hypertension artérielle. Par conséquent, le dosage de l'homocystéine associé à une bonne prise en charge diminuerait le risque cardiovasculaire tout en améliorant la qualité de vie des patients hypertendus.

B-type natriuretic peptide and its role in altering Ca2+-regulatory proteins in heart failure-mechanistic insights

Heart failure (HF) is a worldwide disease with high levels of morbidity and mortality. The pathogenesis of HF is complicated and involves imbalances in hormone and electrolyte. B-type natriuretic peptide (BNP) has served as a biomarker of HF severity, and in recent years, it has been used to treat the disease, thanks to its cardio-protective effects, such as diuresis, natriuresis, and vasodilatation. In stage C/D HF, symptoms are severe despite elevated BNP. Disturbances in Ca²⁺ homeostasis are often a dominating feature of the disease, causing Ca²⁺-regulatory protein dysfunction, including reduced expression and activity of sarcoplasmic reticulum Ca²⁺-ATPase2a (SERCA2a), impaired ryanodine receptors (RYRs) function, intensive Na⁺-Ca²⁺ exchanger (NCX), and downregulation of S100A1. The relationship between natriuretic peptides (NPs) and Ca²⁺-regulatory proteins has been widely studied and represents important mechanisms in the etiology of HF. In this review, we present evidence that BNP may regulate Ca²⁺-regulatory proteins, in particular, suppressing SERCA2a and S100A1 expression. However, relationships between BNP and other Ca²⁺-regulatory proteins remain vague.

Differential Regulation of ANP and BNP in Acute Decompensated Heart Failure: Deficiency of ANP

OBJECTIVES

This study investigated the differential regulation of circulating atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in patients with acute decompensated heart failure (ADHF) and tested the hypothesis that a relative deficiency of ANP exists in a subgroup of patients with ADHF.

BACKGROUND

The endocrine heart releases the cardiac hormones ANP and BNP, which play a key role in cardiovascular (CV), renal, and metabolic homeostasis. In heart failure (HF), both plasma ANP and BNP are increased as a compensatory homeostatic response to myocardial overload.

METHODS

ANP and BNP concentrations were measured in a small group of patients with ADHF (n = 112). To support this study's goal, a total of 129 healthy subjects were prospectively recruited to establish contemporary normal values for ANP and BNP. Plasma 3',5'cyclic guanosine monophosphate (cGMP), ejection fraction (EF), and body mass index (BMI) were measured in these subjects.

RESULTS

In cases of ADHF, 74% of patients showed elevated ANP and BNP. Importantly, 26% of patients were characterized as having normal ANP (21% of this subgroup had normal ANP and elevated BNP). Cyclic GMP was lowest in the ADHF group with normal levels of ANP (p < 0.001), whereas BMI and EF were inversely related to ANP levels (p = 0.003).

CONCLUSIONS

Among a subgroup of patients hospitalized with ADHF, the presence of an ANP deficiency is consistent with a differential regulation of ANP and BNP and suggests the existence of a potentially compromised compensatory cardiac endocrine response. These findings have implications for the pathophysiology, diagnostics, and therapeutics of human HF.

Change in the NT-proBNP/Mature BNP Molar Ratio Precedes Worsening Renal Function in Patients With Acute Heart Failure: A Novel Predictor Candidate for Cardiorenal Syndrome

Background Early detection for worsening renal function (WRF) is indispensable in patients with acute decompensated heart failure (HF). We tested the hypothesis that the difference in the circulating levels of each B-type or brain natriuretic peptide (BNP) molecular form is associated with the occurrence of WRF. Methods and Results Circulating levels of proBNP, the NT-proBNP (N-terminal proBNP), and total BNP (proBNP+mature BNP) were prospectively measured in patients with acute decompensated HF using specific and sensitive enzyme immunochemiluminescent assays. An estimated mature BNP (emBNP) concentration was calculated by subtracting proBNP levels from total BNP levels. WRF was defined as a >20% decrease in the estimated glomerular filtration rate during the hospitalization. One-way repeated-measures ANOVA was used to compare the changes of variables between the patients with and without WRF. In patients with acute decompensated HF (New York Heart Association class III-IV; 96%) hospitalized for HF, NT-proBNP levels did not differ during the hospitalization between patients with and without WRF (n=42 and 140, respectively). By contrast, emBNP levels were lower in patients with WRF than in those without WRF on day 3 after admission. NT-proBNP/emBNP molar ratios were elevated on day 3 after admission in the patients with WRF, before estimated glomerular filtration rate declined, but were unchanged in patients without WRF. On day 3 after hospital admission, NT-proBNP/emBNP ratios were strongly associated with percentage decreases in estimated glomerular filtration rate. Conclusions These findings suggest that elevation of NT-proBNP/emBNP ratio precedes WRF in patients with acute HF and can be a potentially useful biomarker for risk stratification of cardiorenal syndrome.

Maternal androgen excess induces cardiac hypertrophy and left ventricular dysfunction in female mice offspring

Aims

Polycystic ovary syndrome (PCOS) is a common endocrinopathy that is suggested to increase the risk for cardiovascular disease. How PCOS may lead to adverse cardiac outcomes is unclear and here we hypothesized that prenatal exposure to dihydrotestosterone (DHT) and/or maternal obesity in mice induce adverse metabolic and cardiac programming in female offspring that resemble the reproductive features of the syndrome.

Methods and results

The maternal obese PCOS phenotype was induced in mice by chronic high-fat–high-sucrose consumption together with prenatal DHT exposure. The prenatally androgenized (PNA) female offspring displayed cardiac hypertrophy during adulthood, an outcome that was not accompanied by aberrant metabolic profile. The expression of key genes involved in cardiac hypertrophy was up-regulated in the PNA offspring, with limited or no impact of maternal obesity. Furthermore, the activity of NADPH oxidase, a major source of reactive oxygen species in the cardiovascular system, was down-regulated in the PNA offspring heart. We next explored for early transcriptional changes in the heart of newly born PNA offspring, which could account for the long-lasting changes observed in adulthood. Neonatal PNA hearts displayed an up-regulation of transcription factors involved in cardiac hypertrophic remodelling and of the calcium-handling gene, Slc8a2. Finally, to determine the specific role of androgens in cardiovascular function, female mice were continuously exposed to DHT from pre-puberty to adulthood, with or without the antiandrogen flutamide. Continuous exposure to DHT led to adverse left ventricular remodelling, and increased vasocontractile responses, while treatment with flutamide partly alleviated these effects.

Conclusion

Taken together, our results indicate that intrauterine androgen exposure programmes long-lasting heart remodelling in female mouse offspring that is linked to left ventricular hypertrophy and highlight the potential risk of developing cardiac dysfunction in daughters of mothers with PCOS.

The Confounding Effects of Non-cardiac Pathologies on the Interpretation of Cardiac Biomarkers

PURPOSE OF REVIEW

Cardiac biomarkers play important roles in routine evaluation of cardiac patients. But while these biomarkers can be extremely valuable, none of them should ever be used by themselves-without adding the clinical context. This paper explores the non-cardiac pathologies that can be seen with the cardiac biomarkers most commonly used.

RECENT FINDINGS

High-sensitivity troponin assay gained FDA approval for use in the USA, and studies demonstrated its diagnostic utility can be extended to patients with renal impairment. Gender-specific cut points may be utilized for high-sensitivity troponin assays. In the realm of the natriuretic peptides, studies demonstrated states of natriuretic peptide deficiency in obesity and in subjects of African-American race. Regardless, BNP and NT-proBNP both retained prognostic utilities across a variety of comorbid conditions. We are rapidly gaining clinical evidence with use of soluble ST2 and procalcitonin levels in management of cardiac disease states. In order to get the most utility from their measurement, one must be aware of non-cardiac pathologies that may affect the levels of biomarkers as although many of these are actually true values, they may not represent the disease we are trying to delineate. A few take-home points are as follows: 1. A biomarker value should never be used without clinical context 2. Serial sampling of biomarkers is often helpful 3. Panels of biomarkers may be valuable.

Deficiency of T-type Ca2+ channels Cav3.1 and Cav3.2 has no effect on angiotensin II-induced hypertension but differential effect on plasma aldosterone in mice

T-type Ca²⁺ channel Ca_v3.1 promotes microvessel contraction ex vivo. It was hypothesized that in vivo, functional deletion of Ca_v3.1, but not Ca_v3.2, protects mice against angiotensin II (ANG II)-induced hypertension. Mean arterial blood pressure (MAP) and heart rate were measured continuously with chronically indwelling catheters during infusion of ANG II (30 ng·kg^-1·min^-1, 7 days) in wild-type (WT), Ca_v3.1^-/-, and Ca_v3.2^-/- mice. Plasma aldosterone and renin concentrations were measured by radioimmunoassays. In a separate series, WT mice were infused with ANG II (100 ng·kg^-1·min^-1) with and without the mineralocorticoid receptor blocker canrenoate. Ca_v3.1^-/- and Ca_v3.2^-/- mice exhibited no baseline difference in MAP compared with WT mice, but day-night variation was blunted in both Ca_v3.1 and Ca_v3.2^-/- mice. ANG II increased significantly MAP in WT, Ca_v3.1^-/-, and Ca_v3.2^-/- mice with no differences between genotypes. Heart rate was significantly lower in Ca_v3.1^-/- and Ca_v3.2^-/- mice compared with control mice. After ANG II infusion, plasma aldosterone concentration was significantly lower in Ca_v3.1^-/- compared with Ca_v3.2^-/- mice. In response to ANG II, fibrosis was observed in heart sections from both WT and Ca_v3.1^-/- mice and while cardiac atrial natriuretic peptide mRNA was similar, the brain natriuretic peptide mRNA increase was mitigated in Ca_v3.1^-/- mice ANG II at 100 ng/kg yielded elevated pressure and an increased heart weight-to-body weight ratio in WT mice. Cardiac hypertrophy, but not hypertension, was prevented by the mineralocorticoid receptor blocker canrenoate. In conclusion, T-type channels Ca_v3.1and Ca_v3.2 do not contribute to baseline blood pressure levels and ANG II-induced hypertension. Ca_v3.1, but not Ca_v3.2, contributes to aldosterone secretion. Aldosterone promotes cardiac hypertrophy during hypertension.

Characterisation of N-terminal pro-brain natriuretic peptide in dialysis patients and its reduced prognostic significance in the elderly

Characterisation of N-terminal pro-brain natriuretic peptide (NT-proBNP) in chronic haemodialysis patients and its prognostic significance in age stratification have not been addressed. A prospective cohort study with cross-sectional analyses at baseline was performed. Outcomes were all-cause mortality, non-malignancy-related mortality, and cardiovascular disease (CVD)-related mortality. NT-proBNP was significantly higher in elderly, female, and low dry weight patients. Study patients were divided into two groups: Group-O (≥75 years) and Group-Y (<75 years). The 7-year follow-up receiver operating curve analysis showed that NT-proBNP significantly predicted all outcomes. All-cause mortality cut-off points were significantly different among the groups (total cohort, 5375 pg/mL; Group-Y, 3682 pg/mL; Group-O, 11750 pg/mL). Cox regression analysis showed risks for all outcomes by tertile NT-proBNP significantly higher in the total cohort and Group-Y as adjusted by potential confounders. For all-cause mortality, hazard ratios and 95% confidence intervals (CI) were T2 1.70 (0.89 to 3.25), p = 0.11, T3 2.95 (1.54 to 5.67), p < 0.01 in Group-Y; and T2 1.00 (0.64 to 1.58), p = 1.00; T3 1.50 (0.94 to 2.40), p = 0.09 in Group-O. In conclusion, NT-proBNP was significantly higher in elderly, female, and low dry weight chronic dialysis patients. NT-proBNP was significantly associated with all outcomes. However, this association was reduced in elderly patients.

BNP and NT-proBNP as Diagnostic Biomarkers for Cardiac Dysfunction in Both Clinical and Forensic Medicine

Currently, brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are widely used as diagnostic biomarkers for heart failure (HF) and cardiac dysfunction in clinical medicine. They are also used as postmortem biomarkers reflecting cardiac function of the deceased before death in forensic medicine. Several previous studies have reviewed BNP and NT-proBNP in clinical medicine, however, few articles have reviewed their application in forensic medicine. The present article reviews the biological features, the research and application status, and the future research prospects of BNP and NT-proBNP in both clinical medicine and forensic medicine, thereby providing valuable assistance for clinicians and forensic pathologists.