Plasma NT-proBNP increases in response to LPS administration in healthy men

Voluntary wheel running as a promising strategy to promote autonomic resilience to social stress in females: Vagal tone lies at the heart of the matter

Social stress is a major risk factor for comorbid conditions including cardiovascular disease and depression. While women exhibit 2-3× the risk for these stress-related disorders compared to men, the mechanisms underlying heightened stress susceptibility among females remain largely unknown. Due to a lack in understanding of the pathophysiology underlying stress-induced comorbidities among women, there has been a significant challenge in developing effective therapeutics. Recently, a causal role for inflammation has been established in the onset and progression of comorbid cardiovascular disease/depression, with women exhibiting increased sensitivity to stress-induced immune signaling. Importantly, reduced vagal tone is also implicated in stress susceptibility, through a reduction in the vagus nerve's well-recognized anti-inflammatory properties. Thus, examining therapeutic strategies that stabilize vagal tone during stress may shed light on novel targets for promoting stress resilience among women. Recently, accumulating evidence has demonstrated that physical activity exerts cardio- and neuro-protective effects by enhancing vagal tone. Based on this evidence, this mini review provides an overview of comorbid cardiovascular and behavioral dysfunction in females, the role of inflammation in these disorders, how stress may impart its negative effects on the vagus nerve, and how exercise may act as a preventative. Further, we highlight a critical gap in the literature with regard to the study of females in this field. This review also presents novel data that are the first to demonstrate a protective role for voluntary wheel running over vagal tone and biomarkers of cardiac dysfunction in the face of social stress exposure in female rats.

Elevated brain natriuretic peptide in a patient with metastatic cancer without heart failure: A case study

ABSTRACT

Brain natriuretic peptide (BNP) is a well-established biomarker for heart failure (HF). However, its diagnostic utility can be limited in patients with comorbidities that independently elevate serum BNP levels, including chronic renal failure and sepsis. We describe a rare occurrence of significantly elevated serum BNP levels in a patient with metastatic urothelial cancer without HF or obvious signs of sepsis. The report highlights the need for considering alternative causes for increased serum BNP levels, especially in the presence of malignancy.

Predictive value of serum level of B type Natriuretic Peptide (BNP) in neonatal sepsis

"Background: NT-proB-type Natriuretic Peptide (BNP) (NT-pro BNP) is one of the biomarkers that has been studied in recent decades in connection with pediatric heart failure (HF) and congenital heart disease (CHD). Recently, infants hypothesized that serum. NT-pro BNP levels might be a good predictor of septicemia severity and response to treatment and prognosis in these patients. This study investigated the relationship between serum natriuretic type B peptide level and neonatal sepsis. Materials and Method: In this case-control study, all full-term and pre-term neonates admitted to children’s Hospital, TabrizIran(2021), with sepsis and a septicemia diagnosis were confirmed after obtaining consent. The study was deliberately entered by the patient's parents or legal guardian. Complete Blood Count with Differential (CBC/Diff ), C - reactive protein (CRP) , Bacterial Culture (B/C) , Urine Analyze(U/A),Urine Culture (U/C) ,NT-pro BNP were checked and finally compared with laboratory results of the same number of infants who did not have clinical and laboratory symptoms of sepsis. After collecting samples, laboratory results, including serum levels of NT-pro BNP, were compared in case and control groups. Results: One hundred patients were studied in two groups. Thirty-eight patients (38%) were boys, and 62 patients (62%) were girls. The mean age of the patients was 7.58±7.46 days. The mean weight of the studied patients was 2811.80±620.33 grams, with a median of 2855 grams. The most common clinical symptom observed in patients in the case group was fever (100%) followed by Poor feeding (84%). In the control group, all patients had jaundice. Neonates with sepsis had significantly higher initial pro-BNP values than the control group (10023.80 vs. 2247.20; p=0.001). The NT-pro BNP level cut-off point in predicting the final treatment status and mortality of neonates with sepsis was 9583 pg/ml with 97.7% sensitivity and 93.6% specificity. Conclusion: Measurement of serum level of NT-Pro BNP in neonates with sepsis at the time of clinical signs with 97.7% sensitivity and 93.6% specificity with a cut-off point of 9583 is an important prognostic factor in the therapeutic management of patients."

N-terminal Pro-B-Type Natriuretic Peptide is a Myocardial Biomarker in Pulmonary Sepsis and Septic Shock

The objective: to study changes and prognostic significance of the blood NT-proBNP in the patients with pulmonary sepsis.

Subjects and Methods. The study included 34 patients aged 54.5 ± 2.9 years with pulmonary sepsis or septic shock. Lethality in the intensive care unit (ICU) was 47.1%. NT-proBNP, procalcitonin (PCT) levels, blood lactate and hemodynamic parameters were registered on the 1st day (stage 1) and on the 4th-5th day of the ICU stay (stage 2). Hemodynamics was assessed through transpulmonary thermodilution. The differences were considered statistically significant at p < 0.05.

Results: At stage 1, NT-proBNP level was 5,220 [1,380‒17,850] pg/ml, did not decrease (p = 0.726) at stage 2 and amounted to 1,760 [631‒847] pg/ml. At stage 1, NT-proBNP correlated with extravascular lung water index (rho = 0.445; p = 0.038) and systolic pulmonary artery pressure (rho = 0.414; p = 0.023). At stage 2, NT-proBNP correlated with PCT (rho = 0.569; p = 0.003), blood lactate (rho = 0.525; p = 0.001), and mean arterial pressure to norepinephrine dosage ratio (rho = -0.422; p = 0.035). At stage 1, NT-proBNP was no predictor of lethality in the ICU: OR 1.0000; 95% CI 1.0000-1.0001. At stage 2, NT-proBNP > 4,260 pg/ml (sensitivity 87.5%, specificity 94.4%) was a predictor of lethality: OR 1.0004, 95% CI 1.0000-1.0008, p = 0.046 (AUC 0.893, 95% CI 0.732-0.974). Any increase of NT-proBNP level (> 0 pg/ml) between stages 2 and 1 was a predictor of lethality (sensitivity 87.5%, specificity 94.4%): OR 119.0, 95% CI 9.7432‒1,453.4241, p = 0.0002 (AUC 0.903, 95% CI 0.751-0.977).

Conclusion: Patients with pulmonary sepsis are characterized by a significant increase of blood NT-proBNP. At stage 1, the biomarker correlated with pulmonary hypertension and moderate pulmonary edema and was no predictor of lethality. At stage 2, NT-proBNP correlated with the indices of infection and sepsis severity (procalcitonin, blood lactate, and mean arterial blood pressure/norepinephrine dosage ratio). At this stage, NT-proBNP levels greater than 4,000 pg/mL and/or any degree of increase in blood levels of the biomarker were both sensitive and specific predictors of a lethal outcome. Specific features of etiopathogenesis of BNP hyperproduction in pulmonary sepsis make it difficult to interpret the elevation of NT-proBNP as an indicator of septic cardiomyopathy but does not reduce its value as a sensitive and specific predictor of lethality.

Glucagon-like peptide 1 levels predict cardiovascular risk in patients with acute myocardial infarction

AIMS

Glucagon-like peptide 1 (GLP-1) is a gut incretin hormone inducing post-prandial insulin secretion. Glucagon-like peptide 1 levels were recently found to be increased in patients with acute myocardial infarction. Glucagon-like peptide 1 receptor agonists improve cardiovascular outcomes in patients with diabetes. The aim of this study was to assess the predictive capacity of GLP-1 serum levels for cardiovascular outcome in patients with myocardial infarction.

METHODS AND RESULTS

In 918 patients presenting with myocardial infarction [321 ST-segment elevation myocardial infarction and 597 non-ST-segment elevation myocardial infarction (NSTEMI)] total GLP-1, N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and the Global Registry of Acute Coronary Events (GRACE) score were assessed at time of hospital admission. The primary composite outcome of the study was the first occurrence of cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke. Kaplan-Meier survival plots and univariable Cox regression analyses found GLP-1 to be associated with adverse outcome [hazard ratio (HR) of logarithmized GLP-1 values: 6.29, 95% confidence interval (CI): 2.67-14.81; P < 0.0001]. After further adjustment for age, sex, family history of cardiovascular disease, smoking, diabetes, hypertension, hypercholesterinaemia, glomerular filtration rate (GFR) CKD-EPI, hs-CRP, hs-Troponin T, and NT-proBNP levels the HR remained significant at 10.98 (95% CI: 2.63-45.90; P = 0.0010). Time-dependent receiver operating characteristic curve analyses illustrated that GLP-1 levels are a strong indicator for early events. For events up to 30 days after admission, GLP-1 proved to be superior to other biomarkers including hs-Troponin T, GFR CKD-EPI, hs-CRP, and NT-proBNP. Adjustment of the GRACE risk estimate by addition of GLP-1 increased the area under the receiver operating characteristic curve over time in NSTEMI patients.

CONCLUSION

In patients hospitalized for myocardial infarction, GLP-1 levels are associated with cardiovascular events.

Inflammatory markers and incident heart failure in older men: the role of NT-proBNP

Aim:

To determine the relationship between baseline inflammation (CRP and IL-6) with natriuretic peptide (NP) activity (measured by NT-proBNP) and incident heart failure (HF) in older men.

Methods & results:

In the British Regional Heart Study, 3569 men without prevalent myocardial infarction or HF were followed for mean 16.3 years; 327 developed HF. Baseline CRP and IL-6 were significantly and positively associated with NT-proBNP. Those in the highest CRP and IL-6 quartiles had an elevated risk of HF after age and BMI adjustment (HR = 1.42 [1.01–1.98] and 1.71 [1.24–2.37], respectively), which markedly attenuated after NT-proBNP adjustment (HR = 1.15 [0.81–1.63] and 1.25 [0.89–1.75], respectively).

Conclusion:

NP activity is associated with pro-inflammatory biomarkers and may explain the link between inflammation and incident HF.

Inflammation describes the body’s natural response to infections, injuries and toxins. Inflammation is a helpful response in the short term, but it is thought that long-lasting inflammation – for example, due to illnesses such as diabetes or obesity – may have harmful effects. Previous studies have found that people with higher levels of inflammatory molecules in the blood seem to be more likely to develop heart failure (HF) later on. The amount of fluid in the body is controlled, in part, by molecules in the blood known as ‘natriuretic peptides' (NPs). People with HF have much higher levels of NPs in their blood, and these are used to help diagnose HF. There are suggestions that inflammation and natriuretic peptides are linked to one another. Using a sample of men aged 60–79 years, who did not have HF, we compared blood markers of inflammation and NPs at a baseline examination. Men with higher blood inflammatory markers tended to have higher blood NP levels. We then followed these men up for an average of 16.3 years. Men with higher blood inflammatory markers at baseline were more likely to develop HF, as expected, even after accounting for differences in age and BMI. However, when we accounted for NP levels at baseline, the increased risk of HF with inflammation disappeared. This suggests that NP activity is important in the relationship between inflammation and the risk of HF. Future studies should account for this when examining the link. It is possible that NPs or, more likely, whatever is driving their release, may explain why people with inflammation are more likely to get HF.

Brain Natriuretic Peptide for Predicting Contrast-Induced Acute Kidney Injury in Patients with Acute Coronary Syndrome Undergoing Coronary Angiography: A Systematic Review and Meta-Analysis

Objective

To assess the diagnostic value of B-type natriuretic peptide (BNP) or N-terminal pro-B-type natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with acute coronary syndrome (ACS) undergoing coronary angiography.

Background

ACS remains a major cause of death worldwide. Patients with ACS undergoing coronary angiography are more likely to develop CI-AKI, which correlates highly with poor clinical outcomes. Early diagnosis of CI-AKI remains a challenge. Many recent studies have suggested that BNP or NT-proBNP may be a useful biomarker for the early diagnosis of CI-AKI.

Methods

We searched databases (PubMed, EMBASE, and Cochrane Library) to identify eligible studies. Two authors independently screened the studies and extracted data. We used the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) criteria to assess the methodological quality of the included studies and STATA to perform all statistical analyses.

Results

Nine studies including 2832 patients were identified. The pooled sensitivity of 0.73 (95% CI 0.65–0.79), specificity of 0.79 (95% CI 0.70–0.85), and area under the summary receiver operating characteristic curve of 0.81 (95% CI 0.77–0.84) suggested that BNP or NT-proBNP had a good diagnostic value for CI-AKI in patients with ACS undergoing coronary angiography.

Conclusions

Our findings suggest that BNP or NT-proBNP may be an effective predictive marker for CI-AKI. However, additional high-quality studies are required to find the optimal cutoff value and the diagnostic value of BNP or NT-proBNP in combination with other biomarkers.

Inflammation and Circulating Natriuretic Peptide Levels

BACKGROUND

NPs (natriuretic peptides) are cardiac-derived hormones that promote natriuresis, diuresis, and vasodilation. Preclinical evidence suggests that nonhemodynamic triggers for NP release exist, with a few studies implicating inflammatory stimuli. We examined the association between inflammation and NP levels in humans.

METHODS

The associations between inflammation and NP levels were examined in 3 independent studies. First, in 5481 MESA (Multi-Ethnic Study of Atherosclerosis) participants, the cross-sectional (exam 1) and longitudinal (exams 1 to 3) associations between circulating IL6 (interleukin-6) and NT-proBNP (N terminal pro B-type natriuretic peptide) levels were examined in multivariable-adjusted models. Second, in a prospective study of 115 healthy individuals, changes in NP levels were quantified following exposure to lipopolysaccharide as an inflammatory stimulus. Third, in 13 435 hospitalized patients, the association between acute inflammatory conditions and circulating NP levels was assessed using multivariable-adjusted models.

RESULTS

At the baseline MESA exam, each 1-unit higher natural log IL6 was associated with 16% higher NT-proBNP level ([95% CI, 10%-22%]; P=0.002). Each 1-unit higher baseline natural log IL6 level also associated with 6% higher NT-proBNP level ([95% CI, 1%-11%]; P=0.02) at 4-year follow-up. In the lipopolysaccharide study, median NT-proBNP levels rose from 21 pg/mL pre-lipopolysaccharide to 54 pg/mL post-lipopolysaccharide, P<0.001. In the hospitalized patient study, acute inflammatory conditions were associated with 36% higher NP levels ([95% CI, 17%-60%]; P<0.001).

CONCLUSIONS

Inflammation appears to be associated with NP release. Interpretation of NP levels should therefore take into account inflammatory conditions.

Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Is Not Induced in Artificial Human Inflammation and Is Not Correlated with Inflammatory Response

Lipoproteins, as well as proprotein convertase subtilisin/kexin type 9 (PCSK9), have been shown to play a key role in the innate immune response. However, knowledge about the role and kinetics of PCSK9 in human inflammation is currently insufficient. This study aimed to investigate the interaction between inflammation and lipid metabolism, including the possible role of PCSK9. A single-blinded, placebo-controlled cross-over study using the human endotoxin model was performed.

Lipoproteins, as well as proprotein convertase subtilisin/kexin type 9 (PCSK9), have been shown to play a key role in the innate immune response. However, knowledge about the role and kinetics of PCSK9 in human inflammation is currently insufficient. This study aimed to investigate the interaction between inflammation and lipid metabolism, including the possible role of PCSK9. A single-blinded, placebo-controlled cross-over study using the human endotoxin model was performed. Ten healthy men received lipopolysaccharide (LPS) or placebo on two different study days after overnight fasting. Lipoproteins as well as PCSK9 were measured repetitively over 48 h. PCSK9 plasma concentrations were not induced by LPS infusion, and no correlation between PCSK9 plasma concentrations and the degree of inflammation could be identified. The observed low-density lipoprotein (LDL) response to inflammation was more complex than anticipated, especially in the very early phase after the inflammatory stimulus. Baseline concentrations of LDL, as well as high-density lipoprotein (HDL), correlated negatively with inflammatory response. Our data suggest that the lipoprotein response to inflammation is independent of PCSK9. The proposed elevations of PCSK9 and suspected correlations between PCSK9 levels and inflammatory response are not supported by our data. (This study has been registered at ClinicalTrials.gov under registration no. NCT03392701.)

Host Peptidic Hormones Affecting Bacterial Biofilm Formation and Virulence

Bacterial biofilms constitute a critical problem in hospitals, especially in resuscitation units or for immunocompromised patients, since bacteria embedded in their own matrix are not only protected against antibiotics but also develop resistant variant strains. In the last decade, an original approach to prevent biofilm formation has consisted of studying the antibacterial potential of host communication molecules. Thus, some of these compounds have been identified for their ability to modify the biofilm formation of both Gram-negative and Gram-positive bacteria. In addition to their effect on biofilm production, a detailed study of the mechanism of action of these human hormones on bacterial physiology has allowed the identification of new bacterial pathways involved in biofilm formation. In this review, we focus on the impact of neuropeptidic hormones on bacteria, address some future therapeutic issues, and provide a new view of inter-kingdom communication.

Different Dose-Dependent Modes of Action of C-Type Natriuretic Peptide on Pseudomonas aeruginosa Biofilm Formation

We have previously shown that the C-type Natriuretic Peptide (CNP), a peptide produced by lungs, is able to impact Pseudomonasaeruginosa physiology. In the present work, the effect of CNP at different concentrations on P. aeruginosa biofilm formation was studied and the mechanisms of action of this human hormone on P. aeruginosa were deciphered. CNP was shown to inhibit dynamic biofilm formation in a dose-dependent manner without affecting the bacterial growth at any tested concentrations. The most effective concentrations were 1 and 0.1 µM. At 0.1 µM, the biofilm formation inhibition was fully dependent on the CNP sensor protein AmiC, whereas it was only partially AmiC-dependent at 1 µM, revealing the existence of a second AmiC-independent mode of action of CNP on P. aeruginosa. At 1 µM, CNP reduced both P. aeruginosa adhesion on glass and di-rhamnolipid production and also increased the bacterial membrane fluidity. The various effects of CNP at 1 µM and 0.1 µM on P. aeruginosa shown here should have major consequences to design drugs for biofilm treatment or prevention.

The prognostic value of brain natriuretic peptide (BNP) in non-cardiac patients with sepsis, ultra-long follow-up

OBJECTIVES

Sepsis is a multifactorial syndrome with increasing incidence of morbidity and mortality. Identification of outcome predictors is therefore essential. Recently, elevated brain natriuretic peptide (BNP) levels have been observed in patients with septic shock. Little information is available concerning BNP levels in patients with critical illness, especially with sepsis. Therefore, this study aims to evaluate the role of BNP as a biomarker for long-term mortality in patients with sepsis.

METHODS

We studied 259 patients with sepsis and absence of heart failure. BNP levels were obtained for all patients. A long-term survival follow-up was done, and survival was evaluated 90days after admission, and during the subsequent 60months of follow-up.

RESULTS

Eighty-two patients died during the 90-day follow-up (31.7%), 53 died in the index hospitalization (20.5%). On multivariate analysis models, elevated values of BNP were a strong predictor of in-hospital mortality, 90-day and 60-month mortality in patients with sepsis. BNP was a better prognostic predictor than the Sepsis-related Organ Failure Assessment (SOFA) score for 90-day mortality, and a better predictor for 60-month mortality in low risk groups.

CONCLUSION

In the population of hospitalized patients with sepsis, BNP is a strong independent predictor of short- and long-term mortality.

Plasma brain natriuretic peptide levels are elevated in patients with cancer

BACKGROUND

Natriuretic peptides have been proposed as biomarkers of cardiovascular disease, especially heart failure. Brain natriuretic peptide (BNP) has also been shown to be upregulated at the transcriptional and translational levels by pro-inflammatory cytokines in cardiac myocytes. Although we often measure plasma BNP levels in cancer patients, it remains unknown whether cancer-related inflammation affects the plasma BNP levels. We investigated the relationship between the BNP and human cancers.

METHODS

We retrospectively studied 2,923 patients in whom the plasma BNP levels and serum C-reactive protein (CRP) were measured and echocardiography was performed. Patients with clinically evident heart failure (NYHA II or higher), heart disease requiring medical treatment or surgery, renal dysfunction, and inflammatory disease were excluded. There were 234 patients in the final analysis. Blood sampling was performed before surgery and chemotherapy. In addition, we evaluated the relationship between the inflammation and plasma BNP levels in mouse models of colon cancer.

RESULTS

Of the 234 patients, 80 were diagnosed with cancer. Both the plasma BNP and serum CRP levels were significantly higher in cancer patients than those without. There were no significant differences in the echocardiographic parameters. There was a significant positive correlation between the plasma BNP and serum CRP levels in cancer patients (r = 0.360, P<0.01) but not in those without. In cancer patients, only the CRP correlated with the BNP independent of the age, creatinine level, hypertension, and body mass index. In addition, in nude mice with subcutaneous colon cancer, the plasma BNP level was elevated compared with that in non-cancer mice, and there was a significant relationship between the plasma BNP and serum levels of the inflammatory markers.

CONCLUSIONS

In cancer patients, as well as colon cancer model mice, the plasma BNP levels were elevated, possibly due to cancer-related inflammation. The effect of cancer on the BNP levels should be considered when using BNP as an indicator of heart failure in cancer patients.

B-type natriuretic peptide increases cortisol and catecholamine concentrations in healthy subjects

B-type natriuretic peptide (BNP) is a hormone released by the heart in response to volume load and exerts natriuretic properties. It is clinically used as a diagnostic and prognostic biomarker and investigated as a pharmacological agent in the therapy of heart failure. Here we investigate the changes in pituitary, adrenal, and thyroid hormones in response to BNP administration in a randomized single-blinded crossover study conducted in ten healthy men aged 21–29 yr. Participants received in two study sessions a continuous intravenous infusion during 4 h (once placebo and once 3 pmol·kg−1·min−1 BNP) and remained in supine position throughout the study. Circulating concentrations of pituitary, adrenal, and thyroid hormones, heart rate, and blood pressure were measured at baseline and hourly afterwards. BNP prevented the physiological decrease in cortisol during the late morning hours leading to elevated serum cortisol levels ( P = 0.022) and increased circulating epinephrine and norepinephrine concentrations ( P = 0.018 and P = 0.036, respectively). These hormone changes were accompanied by an increase in heart rate ( P = 0.019) but no differences in blood pressure. Taken together, the impact of BNP on the endocrine system extends beyond the well-known inhibition of the renin-angiotensin-aldosterone system and includes increased adrenergic activity and cortisol concentrations. This neuroendocrine activation might impact the outcome of therapeutical BNP administrations and should be further investigated in conditions associated with increased BNP secretion.

NEW & NOTEWORTHY The heart hormone B-type natriuretic peptide (BNP) is increased in patients with heart failure, where it is thought to have beneficial effects by reducing the preload. Here we report that intravenous administration of BNP in men leads to increases in adrenal hormones cortisol, epinephrine, and norepinephrine. Cortisol and catecholamine levels are independent predictors of increased cardiovascular mortality risk; therefore, drugs targeting the BNP system should be evaluated regarding their effects on the neuroendocrine activation accompanying heart failure.

Serum B-type natriuretic peptide levels as a marker for anthracycline-induced cardiotoxicity

Observational and experimental studies have produced inconsistent evidence about the association of serum levels of B-type natriuretic peptide (BNP) with anthracycline-induced cardiotoxicity (AIC). Therefore, the current meta-analysis examined the association between serum BNP levels and AIC by using data from high quality studies published in peer-reviewed journals. Relevant studies were identified through literature searches of China National Knowledge Infrastructure (CNKI), Web of Science, PubMed, Google Scolar and China BioMedicine (CBM). STATA software was used in this meta-analysis for statistical analysis. In addition, the crude standardized mean difference (SMD) with 95% confidence interval (CI) for the highest vs. the lowest category of serum BNP levels was calculated. A total of 8 independent case-control studies, containing 126 AIC patients and 569 healthy controls, were included for the current meta-analysis. The results indicated a significant difference in serum BNP levels between the cardiotoxic group and normal group, with respect to post-treatment and pretreatment with anthracyclines. Specifically, the serum levels of BNP increased remarkably after treatment with anthracyclines in the cardiotoxic group, compared with the normal group. No publication bias was detected in this meta-analysis. The findings of the present study provide strong evidence that serum BNP levels may be associated with AIC.

Pseudomonas aeruginosa Expresses a Functional Human Natriuretic Peptide Receptor Ortholog: Involvement in Biofilm Formation

Considerable evidence exists that bacteria detect eukaryotic communication molecules and modify their virulence accordingly. In previous studies, it has been demonstrated that the increasingly antibiotic-resistant pathogen Pseudomonas aeruginosa can detect the human hormones brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) at micromolar concentrations. In response, the bacterium modifies its behavior to adapt to the host physiology, increasing its overall virulence. The possibility of identifying the bacterial sensor for these hormones and interfering with this sensing mechanism offers an exciting opportunity to directly affect the infection process. Here, we show that BNP and CNP strongly decrease P. aeruginosa biofilm formation. Isatin, an antagonist of human natriuretic peptide receptors (NPR), prevents this effect. Furthermore, the human NPR-C receptor agonist cANF^4-23 mimics the effects of natriuretic peptides on P. aeruginosa, while sANP, the NPR-A receptor agonist, appears to be weakly active. We show in silico that NPR-C, a preferential CNP receptor, and the P. aeruginosa protein AmiC have similar three-dimensional (3D) structures and that both CNP and isatin bind to AmiC. We demonstrate that CNP acts as an AmiC agonist, enhancing the expression of the ami operon in P. aeruginosa. Binding of CNP and NPR-C agonists to AmiC was confirmed by microscale thermophoresis. Finally, using an amiC mutant strain, we demonstrated that AmiC is essential for CNP effects on biofilm formation. In conclusion, the AmiC bacterial sensor possesses structural and pharmacological profiles similar to those of the human NPR-C receptor and appears to be a bacterial receptor for human hormones that enables P. aeruginosa to modulate biofilm expression.

The bacterium Pseudomonas aeruginosa is a highly dangerous opportunist pathogen for immunocompromised hosts, especially cystic fibrosis patients. The sites of P. aeruginosa infection are varied, with predominance in the human lung, in which bacteria are in contact with host molecular messengers such as hormones. The C-type natriuretic peptide (CNP), a hormone produced by lung cells, has been described as a bacterial virulence enhancer. In this study, we showed that the CNP hormone counteracts P. aeruginosa biofilm formation and we identified the bacterial protein AmiC as the sensor involved in the CNP effects. We showed that AmiC could bind specifically CNP. These results show for the first time that a human hormone could be sensed by bacteria through a specific protein, which is an ortholog of the human receptor NPR-C. The bacterium would be able to modify its lifestyle by favoring virulence factor production while reducing biofilm formation.

Association of N-terminal pro-B-type natriuretic peptide with contrast-induced nephropathy and long-term outcomes in patients with chronic kidney disease and relative preserved left ventricular function

The aim of the present article was to evaluate the association of N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) with contrast-induced nephropathy (CIN) and long-term outcomes in patients with chronic kidney disease (CKD) and relative preserved left ventricular function (LVF) undergoing percutaneous coronary intervention (PCI). We prospectively enrolled 1203 consecutive patients with CKD and preserved LVF undergoing elective PCI. The primary end point was the development of CIN, defined as an absolute increase in serum creatinine (SCr) ≥0.5 mg/dL, from baseline within 48 to 72 hours after contrast medium exposure. CIN incidence varied from 2.2% to 5.2%. Univariate logistic analysis showed that lg-NT-pro-BNP was significantly associated with CIN (odds ratio [OR] = 3.93, 95% confidence interval [CI], 2.22-6.97, P < 0.001). Furthermore, lg-NT-pro-BNP remained a significant predictor of CIN (OR = 3.30, 95% CI, 1.57-6.93, P = 0.002), even after adjusting for potential confounding risk factors. These results were confirmed by using other CIN criteria, which were defined as elevations of the SCr by 25% or 0.5 and 0.3 mg/dL from the baseline. The best cutoff value of lg-NT-pro-BNP for detecting CIN was 2.73 pg/mL (537 pg/mL) with 73.1% sensitivity and 70.0% specificity according to the receiver operating characteristic (ROC) analysis (C statistic = 0.754, 95% CI, 0.67-0.84, P < 0.001). In addition, NT-pro-BNP ≥537 pg/mL (2.73 pg/mL, lg-NT-pro-BNP) was associated with an increased risk of all-cause mortality and composite end points during 2.5 years of follow-up. NT-pro-BNP ≥537 pg/mL is independently associated with an increased risk of CIN with different definitions and poor clinical outcomes in patients with CKD and relative preserved LVF undergoing PCI.

Effects of B-type natriuretic peptide on cardiovascular biomarkers in healthy volunteers

Cardiovascular biomarkers provide independent prognostic information in the assessment of mortality and cardiovascular complications. However, little is known about possible interactions between these biomarkers. In the present study, we evaluated the influence of B-type natriuretic peptide (BNP) on midregional-proadrenomedullin (MR-proADM), C-terminal-proendothelin-1 (CT-proET-1), growth differentiation factor-15 (GDF-15), midregional-proatrial natriuretic peptide (MR-proANP), copeptin, and procalcitonin in healthy volunteers. Ten healthy male subjects (mean age 24 yr) participating in a randomized, placebo-controlled, single-blinded crossover study received placebo or 3.0 pmol·kg−1·min−1human BNP 32 during a continuous infusion lasting for 4 h. Effects of BNP on other cardiovascular biomarkers were assessed. BNP did not change concentrations of MR-proADM, copeptin, CT-proET1, GDF-15, or procalcitonin. In contrast, MR-proANP was significantly decreased during BNP infusion. BNP as an established cardiovascular biomarker did not affect plasma concentrations of other cardiovascular biomarkers in a model of healthy volunteers.

Association between N-terminal pro-brain natriuretic peptide levels and contrast-induced nephropathy in patients undergoing percutaneous coronary intervention for acute coronary syndrome

BACKGROUND

Contrast-induced nephropathy (CIN) is associated with significantly increased morbidity and mortality after percutaneous coronary intervention (PCI). Patients with acute coronary syndrome (ACS) are at higher risk for CIN. N-terminal pro-brain natriuretic peptide (NT-proBNP) is closely linked to the prognosis as a strong predictor of both short- and long-term mortality in patients with ACS.

HYPOTHESIS

We hypothesized that NT-proBNP levels on admission can predict the development of CIN after PCI for ACS.

METHODS

A total of 436 patients (age 62.27 ± 13.01 years; 64.2% male) with ACS undergoing PCI enrolled in this study. Admission NT-proBNP levels were measured before PCI. Serum creatinine values were measured before and within 72 hours after the administration of contrast agents. Patients were divided into 2 groups: CIN group and no-CIN group. CIN was defined as an increase in serum creatinine level of ≥0.5 mg/dL or ≥25% above baseline within 72 hours after contrast administration.

RESULTS

CIN developed in 63 patients (14.4%). Baseline NT-proBNP levels were significantly higher in patients who developed CIN compared to those who did not develop CIN (median 774 pg/mL, interquartile range 177.4-2184 vs median 5159 pg/mL, interquartile range 2282-9677, respectively; P < 0.001). Multivariate analysis found that NT-proBNP (odds ratio [OR]: 3.448, 95% confidence interval [CI]: 1.394-8.474, P = 0.007) and baseline creatinine (OR: 6.052, 95% CI: 1.860-19.686, P = 0.003) were independent predictors of CIN.

CONCLUSIONS

Admission NT-proBNP level is an independent predictor of the development of CIN after PCI in ACS.

B-type natriuretic Peptide: not just a heart throb

We present 2 cases of patients with septic shock and discuss changes in B-type natriuretic peptide (BNP) levels. While previous increases in BNP in septic shock were attributed to the accompanying myocardial depression, recent work claims that high levels of BNP in sepsis are related to an alteration in the BNP clearance pathway. We postulate from these cases that increased BNP should not automatically be associated with cardiac dysfunction and may assist in an early, difficult diagnosis of septic shock.

Brain natriuretic Peptide production and secretion in inflammation

Gene expression and secretion of the cardiac polypeptide hormones atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) are simultaneously upregulated in various cardiac disorders such as congestive heart failure, ischemic heart disease, and hypertensive heart disease, in which hemodynamic or neuroendocrine changes are key components in the progression of disease. However, during acute cardiac allograft rejection, plasma BNP levels are increased but not those of ANF. Successful treatment of the rejection episode decreases the elevated plasma BNP to prerejection values suggesting that substances related to inflammation may selectively influence BNP gene expression. Indeed, cytokines such as TNFα and IL-1β selectively stimulate cardiac BNP at the transcriptional and translational levels in cardiomyocyte cultures without affecting ANF. This selective BNP increase is seen in vivo, in addition to acute cardiac allograft rejection, in several circumstances where inflammation significantly contributes to the pathogenesis of disease such as in sepsis and in acute myocarditis.

B-type natriuretic peptide modulates ghrelin, hunger, and satiety in healthy men

Chronic heart failure is accompanied by anorexia and increased release of B-type natriuretic peptide (BNP) from ventricular cardiomyocytes. The pathophysiological mechanisms linking heart failure and appetite regulation remain unknown. In this study, we investigated the impact of intravenous BNP administration on appetite-regulating hormones and subjective ratings of hunger and satiety in 10 healthy volunteers. Participants received in a randomized, placebo-controlled, crossover, single-blinded study (subject) placebo once and 3.0 pmol/kg/min human BNP-32 once administered as a continuous infusion during 4 h. Circulating concentrations of appetite-regulating peptides were measured hourly. Subjective ratings of hunger and satiety were evaluated by visual analog scales. BNP inhibited the fasting-induced increase in total and acylated ghrelin concentrations over time (P = 0.043 and P = 0.038, respectively). In addition, BNP decreased the subjective rating of hunger (P = 0.009) and increased the feeling of satiety (P = 0.012) when compared with placebo. There were no significant changes in circulating peptide YY, glucagon-like peptide 1, oxyntomodulin, pancreatic polypeptide, leptin, and adiponectin concentrations. In summary, our results demonstrate that BNP exerts anorectic effects and reduces ghrelin concentrations in men. These data, taken together with the known cardiovascular properties of ghrelin, support the existence of a heart-gut-brain axis, which could be therapeutically targeted in patients with heart failure and obesity.

Effect of lipopolysaccharide, cytokines, and catecholamines on brain natriuretic peptide release from human myocardium

BACKGROUND

During sepsis and septic shock, elevated plasma concentrations of brain natriuretic peptide (BNP) have been reported but may be related to several underlying mechanisms. The aim of the present experimental study was to investigate the effect of lipopolysaccharide (LPS), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6), dobutamine (Dobu), epinephrine (Epi), and norepinephrine (Nor) on BNP synthesis by atrial human myocardium in vitro.

METHODS

After the approval of local ethics committee, right atrial appendages were obtained during cannulation for cardiac surgery and pinned in a isolated organ bath containing 15 ml of Tyrode's modified solution. Preparations were oxygenated, maintained at 36 ± 0.5°C and stimulated at a frequency of 1 Hz. A 60-min equilibration period was followed by 180-min exposure to 1 μM endothelin 1 (ET-1; n = 9), 20,000 pg/ml TNF-α (n = 10), 1000 pg/ml IL-1β (n = 10), 5000 pg/ml IL-6 (n = 10), 10,000 pg/ml LPS (n = 10), 100 μM Epi (n = 9), 100 μM Nor (n = 10), and 100 μM Dobu (n = 8). No product was added in Control group (n = 10). Two BNP dosages were performed: the first after 60 min of stabilization and the second after 180 min of stimulation. Absolute and relative changes in BNP concentration were compared between groups.

RESULTS

Exposure to ET-1 significantly increased BNP release as compared with Control group. Dobu, Epi, Nor, and LPS significantly increased BNP concentration but not TNF-α, IL-1β, or IL-6.

CONCLUSIONS

In vitro, LPS, Dobu, Epi, and Nor induced BNP synthesis by human atrial myocardium.

B-type natriuretic peptide (BNP) affects the initial response to intravenous glucose: a randomised placebo-controlled cross-over study in healthy men

AIMS/HYPOTHESIS

B-type natriuretic peptide (BNP) is a hormone released from cardiomyocytes in response to cell stretching and elevated in heart failure. Recent observations indicate a distinct connection between chronic heart failure and diabetes mellitus. This study investigated the role of BNP on glucose metabolism.

METHODS

Ten healthy volunteers (25 ± 1 years; BMI 23 ± 1 kg/m(2); fasting glucose 4.6 ± 0.1 mmol/l) were recruited to a participant-blinded investigator-open placebo-controlled cross-over study, performed at a university medical centre. They were randomly assigned (sequentially numbered opaque sealed envelopes) to receive either placebo or 3 pmol kg(-1) min(-1) BNP-32 intravenously during 4 h on study day 1 or 2. One hour after beginning the BNP/placebo infusion, a 3 h intravenous glucose tolerance test (0.33 g/kg glucose + 0.03 U/kg insulin at 20 min) was performed. Plasma glucose, insulin and C-peptide were frequently measured.

RESULTS

Ten volunteers per group were analysed. BNP increased the initial glucose distribution volume (13 ± 1% body weight vs 11 ± 1%, p < 0.002), leading to an overall reduction in glucose concentration (p < 0.001), particularly during the initial 20 min of the test (p = 0.001), accompanied by a reduction in the initial C-peptide levels (1.42 ± 0.13 vs 1.62 ± 0.10 nmol/l, p = 0.015). BNP had no impact on beta cell function, insulin clearance or insulin sensitivity and induced no adverse effects.

CONCLUSIONS/INTERPRETATION

Intravenous administration of BNP increases glucose initial distribution volume and lowers plasma glucose concentrations following a glucose load, without affecting beta cell function or insulin sensitivity. These data support the theory that BNP has no diabetogenic properties, but improves metabolic status in men, and suggest new questions regarding BNP-induced differences in glucose availability and signalling in various organs/tissues.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01324739

FUNDING

The study was funded by Jubilée Fonds of the Austrian National Bank (OeNB-Fonds).

Is mid-regional pro-atrial natriuretic peptide (MRproANP) an accurate marker of bacteremia in pyelonephritis?

INTRODUCTION

Mid-regional pro-atrial natriuretic peptide (MRproANP) increases during systemic infections and could possibly correlate with bacteremia.

METHODS

We determined the characteristics of MRproANP for accuracy to detect positive blood culture.

RESULTS

Bacteremia was positive in 58 (15%) of 347 patients. MRproANP levels increased in patients with bacteremia (98.4 pmol/L [interquartile range (IQR) 68.2-153.1] vs. 66.4 pmol/L [IQR 51.0-90.3], p <0.01). Performance of MRproANP to predict bacteremia [AUC = 0.69, 95%CI: 0.61-0.77] was equivalent to C-reactive protein (0.66 [95%CI: 0.59-0.74], p = 0.53) but less accurate than procalcitonin (0.78 [95%CI: 0.72-0.84], p <0.001).

CONCLUSION

Although MRproANP increased in bacteremic patients with acute pyelonephritis, results of likelihood ratios discarded its use at bedside to predict bacteremia.

C-type natriuretic peptide modulates quorum sensing molecule and toxin production in Pseudomonas aeruginosa

Pseudomonas aeruginosa coordinates its virulence expression and establishment in the host in response to modification of its environment. During the infectious process, bacteria are exposed to and can detect eukaryotic products including hormones. It has been shown that P. aeruginosa is sensitive to natriuretic peptides, a family of eukaryotic hormones, through a cyclic nucleotide-dependent sensor system that modulates its cytotoxicity. We observed that pre-treatment of P. aeruginosa PAO1 with C-type natriuretic peptide (CNP) increases the capacity of the bacteria to kill Caenorhabditis elegans through diffusive toxin production. In contrast, brain natriuretic peptide (BNP) did not affect the capacity of the bacteria to kill C. elegans. The bacterial production of hydrogen cyanide (HCN) was enhanced by both BNP and CNP whereas the production of phenazine pyocyanin was strongly inhibited by CNP. The amount of 2-heptyl-4-quinolone (HHQ), a precursor to 2-heptyl-3-hydroxyl-4-quinolone (Pseudomonas quinolone signal; PQS), decreased after CNP treatment. The quantity of 2-nonyl-4-quinolone (HNQ), another quinolone which is synthesized from HHQ, was also reduced after CNP treatment. Conversely, both BNP and CNP significantly enhanced bacterial production of acylhomoserine lactone (AHL) [e.g. 3-oxo-dodecanoyl-homoserine lactone (3OC12-HSL) and butanoylhomoserine lactone (C4-HSL)]. These results correlate with an induction of lasI transcription 1 h after bacterial exposure to BNP or CNP. Concurrently, pre-treatment of P. aeruginosa PAO1 with either BNP or CNP enhanced PAO1 exotoxin A production, via a higher toxA mRNA level. At the same time, CNP led to elevated amounts of algC mRNA, indicating that algC is involved in C. elegans killing. Finally, we observed that in PAO1, Vfr protein is essential to the pro-virulent effect of CNP whereas the regulator PtxR supports only a part of the CNP pro-virulent activity. Taken together, these data reinforce the hypothesis that during infection natriuretic peptides, particularly CNP, could enhance the virulence of PAO1. This activity is relayed by Vfr and PtxR activation, and a general diagram of the virulence activation cascade involving AHL, HCN and exotoxin A is proposed.

N-terminal-proB-type natriuretic peptide predicts cardiovascular disease events in HIV-infected patients

BACKGROUND

Cardiovascular disease (CVD) is increasing in HIV-infected patients. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a significant predictor of CVD in the general population. We aimed to quantify the risk of CVD events associated with NT-proBNP at baseline in the Strategies for Management of Anti-Retroviral Therapy study.

METHODS

In a nested case-control study, NT-proBNP was measured at baseline in 186 patients who experienced a CVD event over an average of 2.8 years of follow-up and in 329 matched controls. Odds ratios (ORs) associated with baseline levels of NT-proBNP for CVD were estimated using conditional logistic regression.

RESULTS

At baseline median NT-proBNP [interquartile range (IQR)] was 48.1 (18.5, 112.9) pg/ml in patients who developed a CVD event and 25.7 (12.4, 50.2) pg/ml in controls. The unadjusted OR for the highest versus the lowest quartile was 3.7 [95% confidence interval (CI) 2.1-6.5, P < 0.0001]. After adjustment for baseline covariates and CVD risk factors, OR was 2.8 (95% CI 1.4-5.6, P = 0.003); with additional adjustment for IL-6, high-sensitivity C-reactive protein and D-dimer, OR was 2.3 (95% CI 1.1-4.9, P = 0.02).

CONCLUSIONS

Higher levels of NT-proBNP are associated with increased risk of CVD in HIV patients after considering established CVD risk factors and markers for inflammation and thrombosis.

High N-terminal pro-B-type natriuretic peptide: a biomarker of lung cancer?

BACKGROUND

The level of N-terminal pro-B-type natriuretic peptide (NT-proBNP) is affected by many known factors. Our study aimed to evaluate whether other factors, in particular lung cancer, could be responsible for an increase in NT-proBNP levels in a population with no known risk factors for elevated NT-proBNP.

PATIENTS AND METHODS

This study was based on the RIABO (Recueil de l'Ischémie au Bloc Opératoire) database, a single-center registry that prospectively records in elective noncardiac surgery. Patients aged > 75 years and those presenting with 1 or more known risk factors for high NT-proBNP were excluded. Patients were divided into 2 groups according to preoperative NT-proBNP levels: (≥ 125 pg/mL or < 125 pg/mL).

RESULTS

Between October 2005 and February 2007, 439 patients were eligible for inclusion. Among 35 patients with lung cancer, 26 (74%) had elevated NT-proBNP (≥ 125 pg/mL), versus 9 (26%) with NT-proBNP < 125 pg/mL (P < .0001). By multivariate analysis, the presence of lung cancer was an independent risk factor for a level of NT-proBNP ≥ 125 pg/mL (odds ratio, 7; 95% CI, 2.9-17; P < .0001). We also observed an independent relationship between NT-proBNP ≥ 125 pg/mL and age, female sex, smoking status, and C-reactive protein levels.

CONCLUSION

In our study, patients with lung cancer were 7 times more likely to have elevated NT-proBNP (≥ 125 pg/mL). The presence of lung cancer should therefore be taken into account when interpreting NT-proBNP levels. Further studies are warranted to explore the diagnostic value of this marker in lung cancer and to identify the cause of the elevation.

Midregional pro-atrial natriuretic peptide for the diagnosis of cardiac-related dyspnea according to renal function in the emergency department: a comparison with B-type natriuretic peptide (BNP) and N-terminal proBNP

BACKGROUND

Although renal dysfunction influences the threshold values of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) in diagnosis of cardiac-related dyspnea (CRD), its effects on midregional pro-atrial natriuretic peptide (MR-proANP) threshold values are unknown. We evaluated the impact of renal function on MR-proANP concentrations and compared our results to those of BNP and NT-proBNP.

METHODS

MR-proANP, BNP, and NT-proBNP concentrations were measured in blood samples collected routinely from dyspneic patients admitted to the emergency department. Patients were subdivided into tertiles based on their estimated glomerular filtration rate [eGFR, in mL · min(-1) · (1.73 m(2))(-1)]: tertiles 1 (<44.3), 2 (44.3-58.5), and 3 (≥58.6).

RESULTS

Of 378 patients studied, 69% (n = 260) had impaired renal function [<60 mL · min(-1) · (1.73 m(2))(-1)] and 30% (n = 114) had CRD. MR-proANP, BNP, and NT-proBNP concentrations were significantly increased in patients with impaired renal function. In each tertile, all peptides remained significantly increased in CRD patients by comparison with non-CRD patients. By ROC analysis, MR-proANP, BNP, and NT-proBNP threshold values for the diagnosis of CRD increased as eGFR decreased from tertile 3 to tertile 1. Areas under the ROC curve for all peptides were significantly lower in tertile 1. Using adapted thresholds, MR-proANP, BNP, and NT-proBNP remained independently predictive of CRD, even in tertile 1 patients.

CONCLUSIONS

Renal function influences optimum cutoff points of MR-proANP for the diagnosis of CRD. With use of an optimum threshold value adapted to the eGFR category, MR-proANP remains as effective as BNP and NT-proBNP in independently predicting a diagnosis of CRD in the emergency department.

Gram-negative bacterial sensors for eukaryotic signal molecules

Ample evidence exists showing that eukaryotic signal molecules synthesized and released by the host can activate the virulence of opportunistic pathogens. The sensitivity of prokaryotes to host signal molecules requires the presence of bacterial sensors. These prokaryotic sensors, or receptors, have a double function: stereospecific recognition in a complex environment and transduction of the message in order to initiate bacterial physiological modifications. As messengers are generally unable to freely cross the bacterial membrane, they require either the presence of sensors anchored in the membrane or transporters allowing direct recognition inside the bacterial cytoplasm. Since the discovery of quorum sensing, it was established that the production of virulence factors by bacteria is tightly growth-phase regulated. It is now obvious that expression of bacterial virulence is also controlled by detection of the eukaryotic messengers released in the micro-environment as endocrine or neuro-endocrine modulators. In the presence of host physiological stress many eukaryotic factors are released and detected by Gram-negative bacteria which in return rapidly adapt their physiology. For instance, Pseudomonas aeruginosa can bind elements of the host immune system such as interferon-γ and dynorphin and then through quorum sensing circuitry enhance its virulence. Escherichia coli sensitivity to the neurohormones of the catecholamines family appears relayed by a recently identified bacterial adrenergic receptor. In the present review, we will describe the mechanisms by which various eukaryotic signal molecules produced by host may activate Gram-negative bacteria virulence. Particular attention will be paid to Pseudomonas, a genus whose representative species, P. aeruginosa, is a common opportunistic pathogen. The discussion will be particularly focused on the pivotal role played by these new types of pathogen sensors from the sensing to the transduction mechanism involved in virulence factors regulation. Finally, we will discuss the consequence of the impact of host signal molecules on commensally or opportunistic pathogens associated with different human tissue.

[Heart failure in diabetes]

Interactions of glucose metabolism and chronic heart failure have been confirmed by many epidemiologic studies. The association of HbA1c with an increasing risk of heart failure clearly underlines the connection between both diseases. Coronary artery disease (CAD), hypertension and diabetic cardiomyopathy are long-term complications of diabetes mellitus, resulting in diabetic heart failure. Dysfunction of many regulation systems leads to specific diabetic cardiomyopathy, which has been firstly described by Rubler. A reduction in the cardiac expression of the Na-Ca exchanger pump and SERCA2a protein results in an imbalance in cardiac calcium handling. The overactive renin angiotensin aldosteron system (RAAS) also contributes to the impairment of myocardial function. Hyperlipidaemia, hpyerinsulinaemia and hyperglycaemia directly trigger diabetic cardiomyopathy. Generally chronic heart failure is a clinical diagnosis verified by blood tests like NT-proBNP and cardiac ultrasound. Recommendations on treatment of diabetic heart failure are based on subgroup analysis of the large heart failure trials.