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Measurement of natriuretic peptides (NPs) has proven its clinical value as biomarker, especially in the context of heart failure (HF). In contrast, a state of partial NP deficiency appears integral to several conditions in which lower NP concentrations in plasma presage overt cardiometabolic disease. Here, obesity and type 2 diabetes have attracted considerable attention. Other factors—including age, sex, race, genetics, and diurnal regulation—affect the NP “armory” and may leave some individuals more prone to development of cardiovascular disease. The molecular maturation of NPs has also proven complex, with highly variable O-glycosylation within the biosynthetic precursors. The relevance of this regulatory step in post-translational propeptide maturation has recently become recognized in biomarker measurement/interpretation and cardiovascular pathophysiology. An important proportion of people appear to have reduced effective net NP bioactivity in terms of receptor activation and physiological effects. The state of NP deficiency both entails a potential for further biomarker development and could also offer novel pharmacological possibilities. Alleviating the state of NP deficiency before development of overt cardiometabolic disease in selected patients could be a future path for improving precision medicine.

Measurement of natriuretic peptides (NPs) has proven its clinical value as biomarker, especially in the context of heart failure (HF). In contrast, a state partial NP deficiency appears integral to several conditions in which lower NP concentrations in plasma presage overt cardiometabolic disease. Here, obesity and type 2 diabetes have attracted considerable attention. Other factors - including age, sex, race, genetics, and diurnal regulation - affect the NP "armory" and may leave some individuals more prone to development of cardiovascular disease. The molecular maturation of NPs has also proven complex with highly variable O-glycosylation within the biosynthetic precursors. The relevance of this regulatory step in post-translational propeptide maturation has recently become recognized in biomarker measurement/interpretation and cardiovascular pathophysiology. An important proportion of people appear to have reduced effective net NP bioactivity in terms of receptor activation and physiological effects. The state of NP deficiency, then, both entails a potential for further biomarker development and could also offer novel pharmacological possibilities. Alleviating the state of NP deficiency before development of overt cardiometabolic disease in selected patients could be a future path for improving precision medicine.

In patients with ST-elevation myocardial infarction (STEMI) the immune system is activated with an inflammatory response to follow. In STEMI patients with a severe inflammatory response, risk of development of cardiogenic shock (CS) seems increased. Neutrophil Gelatinase-Associated Lipocalin (NGAL) is a glycoprotein released from mature neutrophils and plasma concentration may increase immediately after STEMI. We therefore aimed to assess whether admission NGAL plasma concentration in patients with STEMI was associated with CS development after leaving the catheterization laboratory (late CS) and 30-day all-cause mortality. PATIENTS AND METHODS: From 1,892 consecutive patients with STEMI 1,626 (86%) had plasma NGAL concentration measured upon hospital admission before angiography throughout a 1-year period at two tertiary heart centers in Denmark. Patients were stratified according to NGAL quartiles (Q1-4). To assess late CS development, we adjusted for the Observatoire Régional Breton sur l'Infarctus risk score for late CS. For mortality assessment, we adjusted for gender, age, post-PCI culprit Thrombolysis in myocardial infarction flow, left ventricular ejection fraction (LVEF), kidney dysfunction, and being comatose after cardiac arrest. RESULTS: Increasing NGAL concentration was associated with higher age, more comorbidities, and more critical patient conditions including lower blood pressure and LVEF. When adjusted for factors associated with poor outcome, NGAL remained independently associated with both late CS development (Q4 vs. Q1-3) (OR (95% CI) 3.64 (1.79-7.41) and 30-day mortality (HR (95% CI) 3.18 (1.73-5.84)). CONCLUSION: Admission plasma concentration of NGAL in STEMI patients is independently associated with 30-day all-cause mortality and predictive of late CS development.

Background C-type natriuretic peptide (CNP) is a cardioprotective peptide with high affinity for the ectoenzyme neutral endopeptidase (neprilysin). We aimed to determine whether angiotensin receptor-neprilysin inhibitor treatment acutely affects circulating concentrations of bioactive CNP and its molecular amino-terminal precursor (NT-proCNP). Methods We included 9 and 10 healthy young men in 2 randomized crossover trials with sacubitril/valsartan vs control (Trial 1) and sacubitril/valsartan and sitagliptin vs sitagliptin (Trial 2). The participants were randomized to a single dose of sacubitril/valsartan (194/206 mg) or control at the first visit 30 min prior to a standardized meal intake. We obtained blood samples at 12 time points over 5 h and measured plasma concentrations of NT-proCNP in both trials and CNP in Trial 2. Results NT-proCNP concentrations increased 3.5 h after sacubitril/valsartan treatment, and at 4.5 h concentrations were 42% and 65% higher compared with control in Trial 1 and Trial 2, respectively. The total area under the curve (tAUC)15–270 min was 22% higher (P = 0.007) in Trial 1 and 17% higher with treatment (P = 0.017) in Trial 2. Concentrations of bioactive CNP followed a similar temporal pattern with an increase of 93% at 4.5 h and a 31% higher tAUC15–270 min compared with control (P = 0.001) in Trial 2. Conclusions Sacubitril/valsartan augments circulating concentrations of both bioactive CNP and NT-proCNP in healthy young men. The increase in bioactive CNP is most likely caused by de novo synthesis and secretion rather than diminished breakdown through neprilysin inhibition. ClinicalTrials.gov registration number NCT03717688

Context Inhibitors of the protease neprilysin (NEP) are used for treating heart failure, but are also linked to improvements in metabolism. NEP may cleave proglucagon-derived peptides, including the glucose and amino acid (AA)-regulating hormone glucagon. Studies investigating NEP inhibition on glucagon metabolism are warranted. Objective This work aims to investigate whether NEP inhibition increases glucagon levels. Methods Plasma concentrations of glucagon and AAs were measured in eight healthy men during a mixed meal with and without a single dose of the NEP inhibitor/angiotensin II type 1 receptor antagonist, sacubitril/valsartan (194 mg/206 mg). Long-term effects of sacubitril/valsartan (8 weeks) were investigated in individuals with obesity (n = 7). Mass spectrometry was used to investigate NEP-induced glucagon degradation, and the derived glucagon fragments were tested pharmacologically in cells transfected with the glucagon receptor (GCGR). Genetic deletion or pharmacological inhibition of NEP with or without concomitant GCGR antagonism was tested in mice to evaluate effects on AA metabolism. Results In healthy men, a single dose of sacubitril/valsartan significantly increased postprandial concentrations of glucagon by 228%, concomitantly lowering concentrations of AAs including glucagonotropic AAs. Eight-week sacubitril/valsartan treatment increased fasting glucagon concentrations in individuals with obesity. NEP cleaved glucagon into 5 inactive fragments (in vitro). Pharmacological NEP inhibition protected both exogenous and endogenous glucagon in mice after an AA challenge, while NEP-deficient mice showed elevated fasting and AA-stimulated plasma concentrations of glucagon and urea compared to controls. Conclusion NEP cleaves glucagon, and inhibitors of NEP result in hyperglucagonemia and may increase postprandial AA catabolism without affecting glycemia.

Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Rigshospitalets Forskningsfond (Grant number: 07IO) Hjerteforeningen (Grant number A6024) Lundbeckfonden (Grant number R186-2015-2132) BACKGROUND In patients with ST-elevation myocardial infarction (STEMI) increased inflammatory response is associated with development of cardiogenic shock (CS). Neutrophil Gelatinase-Associated Lipocalin (NGAL) is a glycoprotein released from mature neutrophils and the plasma concentration of NGAL likely increases immediately after STEMI. PURPOSE We aimed to assess whether admission NGAL plasma concentration in patients with STEMI was associated with CS development after leaving the catheterization laboratory (late CS) and 30-day all-cause mortality. MATERIALS AND METHODS From 1892 consecutive patients with STEMI 1626 (86%) had plasma NGAL concentration measured upon hospital admission before angiography throughout a 1-year period at two tertiary heart centers in Denmark. Patients were stratified according to NGAL quartiles (Q1-4). To assess late CS development, we adjusted for the Observatoire Régional Breton sur l’Infarctus (ORBI) risk score for late CS. For mortality assessment, we adjusted for gender, age, post-PCI culprit Thrombolysis in myocardial infarction (TIMI) flow, left ventricular ejection fraction (LVEF), kidney dysfunction, admission lactate concentration and being comatose after cardiac arrest. RESULTS Increasing NGAL concentration was associated with higher age, more comorbidities (hypertension, diabetes, heart failure, previous stroke, and kidney dysfunction) and more critical patient conditions at presentation including lower blood pressure and LVEF. Plasma NGAL concentration was associated with both late CS development and 30-day mortality (Figure). When adjusted for factors associated with poor outcome, NGAL remained independently associated with both late CS development (Q4 vs. Q1-3) (OR (95% CI) 2.64 (1.57-6.03)) and 30-day mortality (HR (95% CI) 3.18 (1.46-6.93)). CONCLUSION High admission plasma concentration of NGAL in patients with STEMI was independently associated late CS development and 30-day all-cause mortality. Abstract Figure. NGAL quartiles and late CS/mortality

Glucagon (gcg) regulates hepatic glucose and amino acid (AA) metabolism, and increased gcg levels (hyperglucagonemia) contribute to hyperglycemia in diabetes. We hypothesized that the enzyme neprilysin (NEP) contributes to gcg degradation. We measured plasma gcg levels during a mixed meal in nine healthy men after a single dose of the NEP-inhibitor/angiotensin II receptor blocker (194 mg sacubitril/206 mg valsartan, 30 min prior to meal), a DPP-4 inhibitor (sitagliptin, 2x100mg), these combined, or the meal alone. Postprandial gcg levels were 2.7-fold higher in sacubitril/valsartan treated individuals compared to controls (P=0.005) and this was not significantly altered by the addition of sitagliptin (P=0.28). Sacubitril/valsartan also lowered postprandial plasma AA levels (P=0.01), but glucose levels were unaffected (P=0.76). In obese individuals (n=7), eight weeks sacubitril/valsartan treatment increased fasting gcg levels (P=0.02). To test whether NEP degrades gcg and diminishes its signaling, we performed mass-spectrometry and assessed cells transfected with the gcg receptor (gcgr). We found that NEP cleaves gcg and that the gcg fragments produced were unable to activate the gcgr. In non-sedated C57BL/6JRj female mice (n=8) NEP inhibition (sacubitril, 0.7 nmol/g) increased gcg levels (P=0.02) and tended to increase AA disappearance (P=0.076) and urea formation (P=0.08) during an AA challenge. A gcgr antagonist (Novo Nordisk; 25-2648, 100 mg/kg) abolished the increase in urea formation observed with sacubitril alone. Gcg levels were increased 1.9-fold (P Disclosure S. Kjeldsen: None. S. Zraika: Research Support; Self; Novartis Pharmaceuticals Corporation. S.M. Mongovin: None. L.H. Hansen: None. D. Terzic: None. P.D. Mark: None. P. Plomgaard: None. J.P. Gøtze: None. M. Winther-Soerensen: None. J. Hunt: None. K.D. Galsgaard: None. M.M. Rosenkilde: Board Member; Self; Synklino. Consultant; Self; Antag Therapeutics, Bainan Biotech. G.H. Goossens: None. E.E. Blaak: None. J.J. Holst: Advisory Panel; Self; AstraZeneca, Merck Sharp & Dohme Corp., Novo Nordisk A/S, Zealand Pharma A/S. Other Relationship; Spouse/Partner; Antag Therapeutics. N.J. Wewer Albrechtsen: Research Support; Self; Mercodia, Novo Nordisk A/S, Novo Nordisk Foundation. Speaker’s Bureau; Self; Merck Sharp & Dohme Corp. Funding Novo Nordisk Foundation (NNF19OC0055001)

Aims Neprilysin degrades natriuretic peptides in circulation and is also suggested to degrade the gut hormones gastrin and cholecystokinin. Neprilysin inhibition has become a therapeutic strategy and thus a regimen in need of further testing in terms of other hormonal axes besides natriuretic peptides. The aim of this study was to examine whether acute inhibition of neprilysin affects meal-induced responses in gastrin and cholecystokinin concentrations in healthy individuals. Methods and results Nine healthy young men were included in an open-labelled, randomized cross-over clinical trial. The participants received a standardized meal (25 g fat, 26 g protein, 42 g carbohydrate) on two separate days with or without a one-time dosage of sacubitril ((194 mg)/valsartan (206 mg)). Blood pressure, heart rate and blood samples were measured and collected during the experiment. Statistical differences between groups were assessed using area under the curve together with an ANOVA with a Bonferroni post hoc test. Sacubitril/valsartan increased the postprandial plasma concentrations of both gastrin and cholecystokinin (80% (AUC0-270 min, P = 0.004) and 60% (AUC0-270 min, P = 0.003), respectively) compared with the control meal. No significant hemodynamic effects were noted (blood pressure, AUC0-270 min, P = 0.86, heart rate, AUC0-270 min, P = 0.96). Conclusion Our study demonstrates that sacubitril/valsartan increases the postprandial plasma concentrations of gastrin and cholecystokinin in healthy individuals. The results thus suggest that neprilysin-mediated degradation of gastrin and cholecystokinin is physiologically relevant and may have a role in heart failure patients treated with sacubitril/valsartan.

ObjectiveTo determine the predictive value of pro-C-type natriuretic peptide (pro-CNP) measurement in plasma sampled on admission from patients presenting with ST-elevation myocardial infarction (STEMI).DesignProspective cohort study.SettingTwo University Hospitals in Denmark.Participants1760 consecutive patients (470 females and 1290 males) with confirmed STEMI.Main outcomes and measuresThe main outcome was all-cause mortality at 1 year after presentation and the primary measure was pro-CNP concentration in plasma at admission in all patients and longitudinal measurements in a consecutive subgroup of 287 patients. A reference population (n=688) defined cut-off values of increased pro-CNP concentrations.ResultsIn all patients, an increased pro-CNP concentration was associated with a higher all-cause mortality after 1 year (HR 1.6, 95% CI 1.1 to 2.4, Plogrank=0.009) including an interaction of sex (p=0.03). In separate sex-stratified analyses, female patients showed increased all-cause mortality (HR1 year 2.6, 95% CI 1.5 to 4.6), Plogrank 1 year 1.1, 95% CI 0.7 to 1.9, Plogrank=0.66). After adjusting for potential risk factors, we found increased pro-CNP concentrations≥the median value to be independently associated with increased risk of mortality in female patients within 1 year (HR per 1 pmol/L increase: 1.04, 95% CI 1.01 to 1.06, p=0.007). Moreover, we found indications of sex differences in pro-CNP concentrations over time (higher pro-CNP in males (4.4, 95% CI −0.28 to 9.1 pmol/L, p=0.07) and interaction of sex and time (p=0.13)), and that hypertension was independently associated with higher pro-CNP (4.5, 95% CI 0.6 to 8.4 pmol/L, p=0.03).ConclusionsIn female but not male patients presenting with STEMI, high concentrations of pro-CNP (≥median) at admission independently indicate a higher risk of all-cause mortality. The findings are remarkably specific for female patients, suggesting a different vascular phenotype beyond traditional measures of coronary artery flow compared with male patients.

Background: Decreased concentrations of pro-atrial-derived natriuretic peptides (proABP) in plasma have been associated with obesity and suggested as a predictor of type 2 diabetes. However, assays for measuring proANP are generally aimed to quantitate higher concentrations of proANP associated with cardiac disease. Therefore, we aimed to measure plasma proANP concentrations in a non-obese Scandinavian reference material and evaluate potential associations of plasma proANP with body mass index (BMI) and plasma glucose, respectively. Methods: We report an optimized processing-independent assay (PIA) for proANP in the lower concentration range. The assay was optimized by raising the amount of radioactive tracer and modifying the mixing ratio of resuspended plasma and buffer. Blood samples from a Scandinavian plasma cohort of 693 healthy subjects were then analyzed and age and gender-specific reference intervals were determined. Results: Simple linear regression analyses of proANP and both BMI and plasma glucose in fasting subjects displayed insignificant associations. Multiple regression analyses supported these findings. However, a higher median plasma concentration of proANP was noted among women Conclusions: Our results show that in a healthy non-obese population, BMI and plasma glucose in fasting subjects do not affect plasma proANP concentrations. Our method should be considered for future studies on low proANP concentration studies, e.g. in obesity and diabetes.

Introduction Endothelial C-type natriuretic peptide (CNP) contributes to the local regulation of vascular homeostasis including a vasodilatory function in the microcirculation when studied in animal models. Clinical investigations have shown that high concentrations of C-type natriuretic peptides in plasma are associated with adverse clinical outcome in subgroups of patients with cardiac disease. Purpose To determine the prognostic potential of pro-C-type natriuretic peptide (proCNP) measurement in plasma sampled on admission of patients with ST-elevation myocardial infarction (STEMI). Methods In 1760 patients (470 women, 1290 men) with confirmed STEMI, we measured proCNP concentration in plasma obtained on hospital admission before coronary angiography. We divided patients into groups of low, normal or raised proCNP concentrations based on lower and upper cut-off values of sex- and age-specific 95% reference intervals from a reference population (688 individuals). We estimated differences in baseline characteristics including medical history and determined the prognostic value of proCNP measurement by Kaplan-Meier plots including log-rank tests and Cox regression survival analyses (expressed as hazard ratio (HR) and 95% confidence interval). Results Raised proCNP concentrations in plasma were associated with a higher prevalence of hypertension (P median) were independently associated with increased risk of death within one year after adjusting for age, plasma concentrations of creatinine and proANP, and quartiles of plasma troponins (HR: 1.02 (1.00–1.05) per 1 pmol/L increase of proCNP, P=0.047). One-year all-cause mortality rates Conclusion In patients with STEMI, a raised concentration of proCNP from plasma sampled on admission was associated with a higher risk of death within one year. However, only women displayed this difference of mortality rate in sex-specific estimates. Moreover, stepwise increases of proCNP concentration in the upper range independently predicted a higher risk of one-year death in women following STEMI after adjusting for potential confounders.

Context Combined inhibition of neprilysin and dipeptidyl peptidase 4 (DPP-4) has been shown to augment plasma concentrations of glucagon-like peptide-1(GLP-1) in animal models, but whether this occurs in humans is unknown. Objective To investigate the effects of inhibition of neprilysin by sacubitril/valsartan alone or in combination with a DPP-4 inhibitor (sitagliptin) on plasma concentrations of GLP-1 in healthy men. Design Two open-labeled crossover studies were performed in human subjects. Setting General community. Participants Nine and 10 healthy young men were included in study 1 and study 2, respectively. Intervention Study participants received a standardized meal (34% carbohydrates, 45% fat, 21% protein; total caloric content, 2106 kJ) combined with a prior dose of either sacubitril/valsartan (194/206 mg) or control in study 1 and in study 2, with a prior dose of sitagliptin (2 ×100 mg, given ∼10 hours apart) either alone or with sacubitril/valsartan (194/206 mg). Main Outcome Measures Plasma concentrations of total and intact GLP-1. Results Sacubitril/valsartan increased postprandial plasma concentrations of total GLP-1 by 67% [total area under the curve (tAUC)0–240min: 3929 ± 344 vs 2348 ± 181 minutes × pmol/L, P = 0.0023] and increased concentrations of intact GLP-1 plasma concentrations more than sitagliptin alone (tAUC0–240min: 1021 ± 114 vs 660 ± 80 minutes × pmol/L, P = 0.01). Plasma concentrations of glucose, insulin, and GIP were not significantly (P > 0.10) changed upon sacubitril/valsartan treatment. Conclusions Sacubitril/valsartan combined with a DPP-4 inhibitor led to markedly higher concentrations of intact GLP-1 than DPP-4 inhibition alone, supporting a role for both neprilysin and DPP-4 in the metabolism of GLP-1 in humans, a finding that may have therapeutic implications.

PurposeThe aim of this study was to investigate structure and function of the heart in subclinical hyperthyroidism (SH) before and after obtaining euthyroidism by radioactive iodine treatment, using high precision and observer-independent magnetic resonance imaging (MRI) technology.MethodsCardiac MRI was performed before and after euthyroidism was obtained by radioactive iodine treatment in 12 otherwise healthy patients (11 women and one man, mean age 59 years, range 44–71 years) with a nodular goiter and SH, and compared with eight healthy controls investigated at baseline. Cardiac data were expressed as an index, as per body surface area, except for heart rate (HR) and ejection fraction.ResultsPost-treatment cardiac MRI was performed in median 139 days after a normalized serum TSH value had been recorded. During treatment, serum TSH increased from (median (range)) 0.01 (0.01–0.09) to 0.88 (0.27–3.99) mU/l. Patients with untreated SH had increased resting HR (PP2 (P=0.034), in HR of 8 bpm (P=0.001), and in cardiac index of 0.24 l/min per m2 (P=0.017).ConclusionsNormalization of thyroid function by radioactive iodine treatment of SH resulted in significant reductions in clinically important heart parameters such as LVMI, HR, and cardiac index. SH should be regarded as a condition in which aggressive treatment should be considered to protect cardiac function.

SummaryBackground Chronic heart failure (HF) is characterized by reduced serum T3 levels and increased activity of the T3 degrading enzyme deiodinase D3. This may result in an intracellular composition of the cardiomyocyte mimicking that of hypothyroidism. Short-term T3-administration to systolic HF patients might be beneficial. Question Does long-term treatment with T3 have a beneficial effect on cardiac function and neurohormonal activation in chronic systolic HF patients with serum T3 levels below 1·6 nmol/l? Design A randomized, double-blind, cross-over, placebo-controlled intervention study with oral T3 treatment twice daily for 3 months. The T3 dose was uptitrated to a final dose avoiding reduced TSH levels. Primary end-point Left-ventricular ejection fraction (LVEF). Methods Cardiac imaging was performed using multiple gated tomographic radionuclide ventriculography (MUGA-SPECT). Neurohormonal stimulation was evaluated by plasma measurements of natriuretic peptides, aldosterone, renin, noradrenalin and copeptin levels. The patients were monitored for potential cardiac arrhythmias at the start of each treatment period. Results Thirteen patients completed the protocol. Mean LVEF was 43%, range: 37–52 and serum T3 levels 1·4 nmol/l (0·9–1·6). The T3 dose was 20 μg per day (10–40). TSH levels did not change between groups, whereas serum T3 levels increased in the active arm. Cardiac function as measured by LVEF, end-diastolic and end-systolic volumes and cardiac output did not change during T3-treatment and neither did the neurohormonal profile. There were no side-effects in terms of cardiac arrhythmias and no change in resting heart rate. Conclusions This study does not support the hypothesis that oral T3 treatment might be beneficial to patients with chronic, stable systolic HF with a modest degree of reduced LVEF and low-normal serum T3 concentrations. The study included both functional studies of heart contractility as well as measures of the neurohormonal activation.

Sylow subgroups are fundamental in the design of asymptotically efficient group-theoretic algorithms, just as they have been in the study of the structure of finite groups. We present efficient parallel (NC) algorithms for finding and conjugating Sylow subgroups of permutation groups, as well as for related problems. Polynomial-time solutions to these problems were obtained more than a dozen years ago, exploiting a well-developed polynomial-time library. We replace some of those highly sequential procedures with ones that work through a polylog-length normal series that is a by-product of NC membership-testing. As in previous investigations, we reduce to the base case of simple groups, and handle this by a case-by-case analysis that depends heavily upon the classification of finite simple groups.

In the last decades, the developmental origins of health and disease (DOHaD) have emerged as a vigorous field combining experimental, clinical and public health research. Its goal is to understand how events in early life shape later morbidity risk, especially of non-communicable chronic disease. As these diseases become the major cause of morbidity and mortality worldwide, research arising from DoHaD is likely to gain significance to public health and economic development. In this article, we provide a succinct historical review of the resesarch into the relationship between development and later disease, consider the evolutionary and developmental significance and discuss the underlying mechanisms of the DOHaD phenomenon.