Objectives: Using a novel, specific assay for proBNP(1-108), this study tested the hypotheses that proBNP(1-108) is secreted by both nonfailing and failing human hearts and that proBNP(1-108) secretion is increased in failing hearts.
Background: The prohormone of B-type natriuretic peptide (proBNP(1-108)) is a 108-amino acid peptide produced primarily by the heart and cleaved into biologically active BNP(1-32) and the biologically inactive NT-proBNP(1-76). It is unknown to what extent increased cardiac proBNP1-108 secretion compared to reduced peripheral processing is responsible for elevated proBNP(1-108) levels in patients with heart failure (HF) compared to subjects without HF.
Both cardiovascular and renal diseases are common and frequently coexist in the same patient. Indeed, renal dysfunction has been shown to be a more powerful independent predictor of poor outcomes in heart failure (HF) than left ventricular ejection fraction or functional class. Furthermore, acute kidney injury is a frequent therapeutic concern in heart failure.
View Article and Find Full Text PDFG protein-coupled receptors have been successfully targeted by numerous therapeutics including drugs that have transformed the management of cardiovascular disease. However, many GPCRs, when activated or blocked by drugs, elicit both beneficial and adverse pharmacology. Recent work has demonstrated that in some cases, the salutary and deleterious signals linked to a specific GPCR can be selectively targeted by "biased ligands" that entrain subsets of a receptor's normal pharmacology.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
January 2013
In heart failure (HF), the cardiac hormone natriuretic peptides (NPs) atrial (ANP), B-type (BNP), and C-type (CNP) play a key role to protect cardiac remodeling. The proprotein convertases corin and furin process their respective pro-NPs into active NPs. Here we define in a canine model of HF furin and corin gene and protein expression in normal and failing left atrium (LA) or ventricle (LV) testing the hypothesis that the NP proproteins convertases production is altered in experimental HF.
View Article and Find Full Text PDFObjectives: This study sought to investigate plasma levels of circulating cardiac natriuretic peptides, atrial natriuretic peptide (ANP) and B-type or brain natriuretic peptide (BNP), in the general community, focusing on their relative differences in worsening human hypertension.
Background: Although ANP and BNP are well-characterized regulators of blood pressure in humans, little is known at the population level about their relationship with hypertension. The authors hypothesized that hypertension is associated with a lack of activation of these hormones or their molecular precursors.
Background: TRV120027 is a novel β-arrestin biased ligand of the angiotensin II type 1 receptor; it antagonizes canonical G-protein-mediated coupling while, in contrast to classical angiotensin II type 1 receptor antagonists, it engages β-arrestin-mediated signaling. Consequently, TRV120027 inhibits angiotensin II-mediated vasoconstriction while, via β-arrestin coupling, it increases cardiomyocyte contractility. We hypothesized that TRV120027 would elicit beneficial cardiorenal actions when added to furosemide in experimental heart failure.
View Article and Find Full Text PDFBackground: The angiotensin II type 1 receptor (AT1R) plays a key role in regulating cardiorenal function. Classic "unbiased" AT1R antagonists block receptor coupling to both G(αq) and ß-arrestin-mediated signals, which desensitize G-protein signaling as well as transduce G-protein-independent signals. TRV120027 is a novel ß-arrestin-biased AT1R ligand, which engages ß-arrestins while blocking G-protein signaling.
View Article and Find Full Text PDFObjectives: We sought to define the cardiometabolic phenotype associated with rs5068, a genetic variant of the atrial natriuretic peptide (ANP) gene.
Background: The ANP and B-type natriuretic peptide play an important role in cardiorenal homeostasis but also exert metabolic actions.
Methods: We genotyped 1,608 randomly selected residents from Olmsted County, Minnesota.
Objectives: The purpose of this study was to investigate circulating pro-B-type natriuretic peptide (proBNP(1-108)) in the general community and evaluate its ability to detect left ventricular (LV) dysfunction.
Background: The current concept for cardiac endocrine function is that, in response to cardiac stress, the heart secretes B-type natriuretic peptide (BNP(1-32)) and amino-terminal pro-B-type natriuretic peptide (NT-proBNP(1-76)) after intracardiac cleavage of their molecular precursor, proBNP(1-108). We hypothesized that proBNP(1-108) circulates in normal human subjects and that it is a useful biomarker for LV dysfunction.
Objective: To assess in a US general adult population the effect of the functional single-nucleotide polymorphism rs198389 in the promoter region of the gene of brain-type natriuretic peptide (BNP) on 3 commonly used BNP assays, clinical phenotype, disease prevalence, overall survival, and diagnostic test characteristics of BNP as a biomarker.
Patients And Methods: We genotyped for rs198389 in a random sample of the general population (aged ≥ 45 years; n = 1970; enrolled between June 1, 1997, and September 30, 2000) from Olmsted County, Minnesota. Patients were characterized biochemically, clinically, echocardiographically, and regarding BNP molecular forms (2 assays for BNP and 1 assay for amino-terminal proBNP).
M-atrial natriuretic peptide (ANP; M-ANP) is a novel next generation 40 amino acid peptide based on ANP, which is highly resistant to enzymatic degradation and has greater and more sustained beneficial actions compared with ANP. The current study was designed to advance our understanding of the therapeutic potential of M-ANP in a canine model of acute angiotensin II-induced hypertension with elevated cardiac filling pressures and aldosterone activation. We compare M-ANP with vehicle and equimolar human B-type natriuretic peptide, which possesses the most potent in vivo actions of the native natriuretic peptides.
View Article and Find Full Text PDFBackground: Reductions in numbers of circulating progenitor cells (CD34+ cell subsets) have been demonstrated in patients at risk for, or in the presence of, cardiovascular disease. The mediators of these reductions remain undefined. To determine whether neurohumoral factors might regulate circulating CD34+ cell subsets in vivo, we studied complementary canine models of left ventricular (LV) dysfunction.
View Article and Find Full Text PDFBackground: Hemodynamic and neurohumoral function can affect the efficacy of diuretic therapy in congestive heart failure. Arginine vasopressin increases water reabsorption through the V(2) receptor in the collecting duct, whereas B-type natriuretic peptide (BNP) decreases sodium reabsorption in the collecting duct. We hypothesized that combining BNP to the V(2)-receptor antagonist tolvaptan (TLV) would enhance renal excretory function by augmenting sodium excretion together with aquaresis without adversely affecting renal hemodynamics in experimental congestive heart failure.
View Article and Find Full Text PDFCirculating levels of the BNP system can help in the diagnosis of cardiovascular disease and provide prognostic information not only for patients who have HF but also for the general population and other patient groups. Changes over time also carry prognostic information, and studies are assessing BNP-guided treatment strategies. With the identification of circulating molecular forms of BNP, new insights regarding the biology of the BNP system are emerging that may improve the diagnostic and prognostic value of BNP.
View Article and Find Full Text PDFAlternative RNA splicing may provide unique opportunities to identify drug targets and therapeutics. We identified an alternative spliced transcript for B-type natriuretic peptide (BNP) resulting from intronic retention. This transcript is present in failing human hearts and is reduced following mechanical unloading.
View Article and Find Full Text PDF32-amino acid B-type natriuretic peptide (BNP 1-32) plays an important role in cardiovascular homeostasis. Recently, it was reported that BNP 1-32 is cleaved by the metalloprotease meprin A to BNP 8-32, the bioactivity of which is undefined. We hypothesized that BNP 8-32 has reduced vasodilating and natriuretic bioactivity compared with BNP 1-32 in vivo.
View Article and Find Full Text PDFHeart failure (HF) is a common disease that continues to be associated with high morbidity and mortality warranting novel therapeutic strategies. Cyclic guanosine monophosphate (cGMP) is the second messenger of several important signaling pathways based on distinct guanylate cyclases (GCs) in the cardiovascular system. Both the nitric oxide/soluble GC (NO/sGC) as well as the natriuretic peptide/GC-A (NP/GC-A) systems are disordered in HF, providing a rationale for their therapeutic augmentation.
View Article and Find Full Text PDFBackground: We previously reported the feasibility of an acute, orally delivered, newly developed, conjugated form of human B-type natriuretic peptide (hBNP) in normal animals. The objective of the present study was to extend our findings and to define the chronic actions of an advanced oral conjugated hBNP (hBNP-054) administered for 6 days on sodium excretion and blood pressure. We also sought to establish the ability of this new conjugate to acutely activate cGMP and to reduce blood pressure in an experimental model of angiotensin II (ANG II) -mediated hypertension.
View Article and Find Full Text PDFCongestive heart failure (CHF) is characterized by fluid and water retention, which frequently is a therapeutic challenge. Most conventional diuretics act primarily as saluretics, i.e.
View Article and Find Full Text PDFNatriuretic peptides (NPs) secreted by the heart in response to volume overload are pleiotropic molecules with vasodilating, diuretic, natriuretic, antiproliferative, and antifibrotic actions. Functioning of the NP system is altered in congestive heart failure (CHF), suggesting that support of the NP system might be beneficial in treatment of acute and chronic CHF. Several approaches alone or in combination with other pharmacologic therapies have been shown to enhance function of the NP system: direct administration of native and designer NPs, inhibition of degradation of NPs and their second messenger (cyclic guanosine monophosphate ), and stimulation of cGMP generation.
View Article and Find Full Text PDFBackground: Renal dysfunction is an important independent prognostic factor in heart failure (HF). Cardiac resynchronization therapy (CRT) improves functional status and left ventricular (LV) function in HF patients with ventricular dyssynchrony, but the impact of CRT on renal function is less defined. We hypothesized that CRT would improve glomerular filtration rate as estimated by the abbreviated Modification of Diet in Renal Disease equation (eGFR).
View Article and Find Full Text PDFThe prevalence and incidence of congestive heart failure continues to increase. The two hallmarks of this syndrome, sodium and water retention, are frequently a therapeutic challenge. Most conventional diuretics act primarily as saluretics by inhibiting renal tubular electrolyte reabsorption, which, due to osmotic pressure, promotes excretion of isotonic fluid.
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