Despite the success of renin-angiotensin system (RAS) blockade by angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor (AT
R) blockers, current therapies for hypertension ...and related cardiovascular diseases are still inadequate. Identification of additional components of the RAS and associated vasoactive pathways, as well as new structural and functional insights into established targets, have led to novel therapeutic approaches with the potential to provide improved cardiovascular protection and better blood pressure control and/or reduced adverse side effects. The simultaneous modulation of several neurohumoral mediators in key interconnected blood pressure-regulating pathways has been an attractive approach to improve treatment efficacy, and several novel approaches involve combination therapy or dual-acting agents. In addition, increased understanding of the complexity of the RAS has led to novel approaches aimed at upregulating the ACE2/angiotensin-(1-7)/Mas axis to counter-regulate the harmful effects of the ACE/angiotensin II/angiotensin III/AT
R axis. These advances have opened new avenues for the development of novel drugs targeting the RAS to better treat hypertension and heart failure. Here we focus on new therapies in preclinical and early clinical stages of development, including novel small molecule inhibitors and receptor agonists/antagonists, less conventional strategies such as gene therapy to suppress angiotensinogen at the RNA level, recombinant ACE2 protein, and novel bispecific designer peptides.
The number of studies concerning Submarine Groundwater Discharge (SGD) grew quickly as we entered the 21st century. Many hydrological and oceanographic processes that drive and influence SGD were ...identified and characterized during this period. These processes included tidal effects on SGD, water and solute fluxes, biogeochemical transformations through the subterranean estuary, and material transport via SGD from land to sea. Here we compile and summarize the significant progress in SGD assessment methodologies, considering both the terrestrial and marine driving forces, and local as well as global evaluations of groundwater discharge with an emphasis on investigations published over the past decade. Our treatment presents the state-of-the-art progress of SGD studies from geophysical, geochemical, bio-ecological, economic, and cultural perspectives. We identify and summarize remaining research questions, make recommendations for future research directions, and discuss potential future challenges, including impacts of climate change on SGD and improved estimates of the global magnitude of SGD.
Societal Impact Statement
Therapeutic protein production in plants is an area of great potential for increasing and improving the production of proteins for the treatment or prevention of disease in ...humans and other animals. There are a number of key benefits of this technique for scientists and society, as well as regulatory challenges that need to be overcome by policymakers. Increased public understanding of the costs and benefits of therapeutic protein production in plants will be instrumental in increasing the acceptance, and thus the medical and veterinary impact, of this approach.
Summary
Therapeutic recombinant proteins are a powerful tool for combating many diseases which have previously been hard to treat. The most utilized expression systems are Chinese Hamster Ovary cells and Escherichia coli, but all available expression systems have strengths and weaknesses regarding development time, cost, protein size, yield, growth conditions, posttranslational modifications and regulatory approval. The plant industry is well established and growing and harvesting crops is easy and affordable using current infrastructure. Growth conditions are generally simple: sunlight, water, and the addition of cheap, available fertilizers. There are multiple options for plant expression systems, including species, genetic constructs and protein targeting, each best suited to a particular type of therapeutic protein production. Transient expression systems provide a mechanism to rapidly transfect plants and produce therapeutic protein in a matter of weeks, rather than the months it can take for many competing expression systems, while proteins targeted to cereal seeds can be harvested, stored and potentially purified much more easily than in competing systems. Current challenges for plant expression systems include a lack of regulatory approval, environmental containment concerns and nonhuman glycosylation, which may limit the scope of the type of therapeutic proteins that can be manufactured in plants. The specific strengths of plant expression systems could facilitate the production of certain therapeutic proteins quickly and cheaply in the near future.
Therapeutic protein production in plants is an area of great potential for increasing and improving the production of proteins for the treatment or prevention of disease in humans and other animals. There are a number of key benefits of this technique for scientists and society, as well as regulatory challenges that need to be overcome by policymakers. Increased public understanding of the costs and benefits of therapeutic protein production in plants will be instrumental in increasing the acceptance, and thus the medical and veterinary impact, of this approach.
Signs and symptoms of congestion are the most common cause for hospitalization for heart failure (HHF). The clinical course and prognostic value of congestion during HHF has not been systemically ...characterized.
A post hoc analysis was performed of the placebo group (n = 2061) of the EVEREST trial, which enrolled patients within 48 h of admission (median ~24 h) for worsening HF with an EF ≤ 40% and two or more signs or symptoms of fluid overload dyspnoea, oedema, or jugular venous distension (JVD) for a median follow-up of 9.9 months. Clinician-investigators assessed patients daily for dyspnoea, orthopnoea, fatigue, rales, pedal oedema, and JVD and rated signs and symptoms on a standardized 4-point scale ranging from 0 to 3. A modified composite congestion score (CCS) was calculated by summing the individual scores for orthopnoea, JVD, and pedal oedema. Endpoints were HHF, all-cause mortality (ACM), and ACM + HHF. Multivariable Cox regression models were used to evaluate the risk of CCS at discharge on outcomes at 30 days and for the entire follow-up period. The mean CCS obtained after initial therapy decreased from the mean ± SD of 4.07 ± 1.84 and the median (25th, 75th) of 4 (3, 5) at baseline to 1.11 ± 1.42 and 1 (0, 2) at discharge. At discharge, nearly three-quarters of study participants had a CCS of 0 or 1 and fewer than 10% of patients had a CCS >3. B-type natriuretic peptide (BNP) and amino terminal-proBNP, respectively, decreased from 734 (313, 1523) pg/mL and 4857 (2251, 9642) pg/mL at baseline to 477 (199, 1079) pg/mL, and 2834 (1218, 6075) pg/mL at discharge/Day 7. A CCS at discharge was associated with increased risk (HR/point CCS, 95% CI) for a subset of endpoints at 30 days (HHF: 1.06, 0.95-1.19; ACM: 1.34, 1.14-1.58; and ACM + HHF: 1.13, 1.03-1.25) and all outcomes for the overall study period (HHF: 1.07, 1.01-1.14; ACM: 1.16, 1.09-1.24; and ACM + HHF 1.11, 1.06-1.17). Patients with a CCS of 0 at discharge experienced HHF of 26.2% and ACM of 19.1% during the follow-up.
Among patients admitted for worsening signs and symptoms of HF and reduced EF, congestion improves substantially during hospitalization in response to standard therapy alone. However, patients with absent or minimal resting signs and symptoms at discharge still experienced a high mortality and readmission rate.
Behavioral choice is ubiquitous in the animal kingdom and is central to goal-oriented behavior. Hypothalamic Agouti-related peptide (AgRP) neurons are critical regulators of appetite. Hungry animals, ...bombarded by multiple sensory stimuli, are known to modify their behavior during times of caloric need, rapidly adapting to a consistently changing environment. Utilizing ARCAgRP neurons as an entry point, we analyzed the hierarchical position of hunger related to rival drive states. Employing a battery of behavioral assays, we found that hunger significantly increases its capacity to suppress competing motivational systems, such as thirst, anxiety-related behavior, innate fear, and social interactions, often only when food is accessible. Furthermore, real-time monitoring of ARCAgRP activity revealed time-locked responses to conspecific investigation in addition to food presentation, further establishing that, even at the level of ARCAgRP neurons, choices are remarkably flexible computations, integrating internal state, external factors, and anticipated yield.
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•ARCAgRP activation directs biased caloric consumption•ARCAgRP stimulation suppresses anxiety-like behavior depending on food location•ARCAgRP activation competes with innate motivational drives•ARCAgRP neural activity responds to food and conspecifics
Burnett et al. investigate the competitive influence of physiological and simulated hunger state on orthogonal motivated behaviors, revealing that a subset of hypothalamic neurons respond to initial investigative contact with a conspecific in addition to food cues.
Neprilysin (NEP) is a membrane-bound neutral endopeptidase that degrades a variety of bioactive peptides. The substrates include natriuretic peptides (NPs), which are important regulating mediators ...for cardiovascular and renal biology. Inhibition of NEP activity and exogenous NP administration thus have emerged as potential therapeutic strategies for treating cardiorenal diseases. More recently, B-type natriuretic peptide (BNP) or N-terminal-proBNP (NT-proBNP), 3'-5' cyclic guanosine monophosphate (cGMP), and soluble NEP as biomarkers have also been investigated in heart failure (HF) trials and their predictive value are beginning to be recognized.
The biological functions of NEP and NPs are discussed. Enhancing NPs through NEP inhibition combined with renin-angiotensin-aldosterone system (RAAS) antagonism has proved to be successful in HF treatment, although future surveillance studies will be required. Direct NP enhancement through peptide delivery may have fewer potentially hazardous effects compared to NEP inhibition. Strategies of combined inhibition on NEP with other cardiorenal pathophysiological pathways are promising. Finally, monitoring BNP/NT-proBNP/cGMP concentrations during NEP inhibition treatment may provide supplemental benefits to conventional biomarkers, and the identification of soluble NEP as a novel biomarker for HF needs further investigation.
In this review, the biology of NEP is summarized, with a focus on NP regulation. The degradation of NPs by NEP provides the rationale for NEP inhibition as a strategy for cardiorenal disease treatment. We also describe the current therapeutic strategies of NEP inhibition and NP therapeutics in cardiorenal diseases. Moreover, the discovery of its circulating form, soluble NEP, as a biomarker is also discussed.
With the discovery of atrial natriuretic peptide (ANP), the heart as an endocrine organ was established. Basic science revealed that ANP, through the particulate guanylyl cyclase A receptor and cGMP, ...plays a fundamental role in cardiorenal biology. This work has led to the development of ANP as a therapeutic, especially in heart failure (HF). Human genomics has strengthened our understanding of ANP, revealing specific ANP gene variants that may be associated with biological dysfunction, but also may mediate protective properties, including in metabolic syndrome. Advances in understanding the processing and degradation of ANP molecular forms have resulted in therapeutic breakthroughs, especially inhibition of ANP degradation by neprilysin inhibitors. Although ANP is administered intravenously for acute HF, a novel therapeutic strategy is its chronic delivery by subcutaneous injection. An innovative therapeutic development is engineering to develop ANP-based peptides for chronic use. These interconnected topics of ANP biology and therapeutics will be reviewed in detail.
With sacubitril/valsartan treatment, B-type natriuretic peptide (BNP) concentrations increase; it remains unclear whether change in BNP concentrations is similar across all assays for its ...measurement. Effects of sacubitril/valsartan on atrial natriuretic peptide (ANP) concentrations in patients are unknown. Lastly, the impact of neprilysin inhibition on mid-regional pro-ANP (MR-proANP), N-terminal pro-BNP (NT-proBNP), proBNP1-108, or C-type natriuretic peptide (CNP) is not well understood.
This study sought to examine the effects of sacubitril/valsartan on results from different natriuretic peptide assays.
Twenty-three consecutive stable patients with heart failure and reduced ejection fraction were initiated and titrated on sacubitril/valsartan. Change in ANP, MR-proANP, BNP (using 5 assays), NT-proBNP (3 assays), proBNP1-108, and CNP were measured over 3 visits.
Average time to 3 follow-up visits was 22, 46, and 84 days. ANP rapidly and substantially increased with initiation and titration of sacubitril/valsartan, more than doubling by the first follow-up visit (+105.8%). Magnitude of ANP increase was greatest in those with concentrations above the median at baseline (+188%) compared with those with lower baseline concentrations (+44%); ANP increases were sustained. Treatment with sacubitril/valsartan led to inconsistent changes in BNP, which varied across methods assessed. Concentrations of MR-proANP, NT-proBNP, and proBNP1-108 variably declined after treatment; whereas CNP concentrations showed no consistent change.
Initiation and titration of sacubitril/valsartan led to variable changes in concentrations of multiple natriuretic peptides. These results provide important insights into the effects of sacubitril/valsartan treatment on individual patient results, and further suggest the benefit of neprilysin inhibition may be partially mediated by increased ANP concentrations.
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CONTEXT Heart failure incidence increases with advancing age, and approximately half of patients with heart failure have preserved left ventricular ejection fraction. Although diastolic dysfunction ...plays a role in heart failure with preserved ejection fraction, little is known about age-dependent longitudinal changes in diastolic function in community populations. OBJECTIVE To measure changes in diastolic function over time and to determine the relationship between diastolic dysfunction and the risk of subsequent heart failure. DESIGN, SETTING, AND PARTICIPANTS Population-based cohort of participants enrolled in the Olmsted County Heart Function Study. Randomly selected participants 45 years or older (N = 2042) underwent clinical evaluation, medical record abstraction, and echocardiography (examination 1 1997-2000). Diastolic left ventricular function was graded as normal, mild, moderate, or severe by validated Doppler techniques. After 4 years, participants were invited to return for examination 2 (2001-2004). The cohort of participants returning for examination 2 (n = 1402 of 1960 surviving 72%) then underwent follow-up for ascertainment of new-onset heart failure (2004-2010). MAIN OUTCOME MEASURES Change in diastolic function grade and incident heart failure. RESULTS During the 4 (SD, 0.3) years between examinations 1 and 2, diastolic dysfunction prevalence increased from 23.8% (95% confidence interval CI, 21.2%-26.4%) to 39.2% (95% CI, 36.3%-42.2%) (P < .001). Diastolic function grade worsened in 23.4% (95% CI, 20.9%-26.0%) of participants, was unchanged in 67.8% (95% CI, 64.8%-70.6%), and improved in 8.8% (95% CI, 7.1%-10.5%). Worsened diastolic dysfunction was associated with age 65 years or older (odds ratio, 2.85 95% CI, 1.77-4.72). During 6.3 (SD, 2.3) years of additional follow-up, heart failure occurred in 2.6% (95% CI, 1.4%-3.8%), 7.8% (95% CI, 5.8%-13.0%), and 12.2% (95% CI, 8.5%-18.4%) of persons whose diastolic function normalized or remained normal, remained or progressed to mild dysfunction, or remained or progressed to moderate or severe dysfunction, respectively (P < .001). Diastolic dysfunction was associated with incident heart failure after adjustment for age, hypertension, diabetes, and coronary artery disease (hazard ratio, 1.81 95% CI, 1.01-3.48). CONCLUSIONS In a population-based cohort undergoing 4 years of follow-up, prevalence of diastolic dysfunction increased. Diastolic dysfunction was associated with development of heart failure during 6 years of subsequent follow-up.
Prader-Willi syndrome (PWS) is caused by a loss of paternally expressed genes in an imprinted region of chromosome 15q. Among the canonical PWS phenotypes are hyperphagic obesity, central ...hypogonadism, and low growth hormone (GH). Rare microdeletions in PWS patients define a 91-kb minimum critical deletion region encompassing 3 genes, including the noncoding RNA gene SNORD116. Here, we found that protein and transcript levels of nescient helix loop helix 2 (NHLH2) and the prohormone convertase PC1 (encoded by PCSK1) were reduced in PWS patient induced pluripotent stem cell-derived (iPSC-derived) neurons. Moreover, Nhlh2 and Pcsk1 expression were reduced in hypothalami of fasted Snord116 paternal knockout (Snord116p-/m+) mice. Hypothalamic Agrp and Npy remained elevated following refeeding in association with relative hyperphagia in Snord116p-/m+ mice. Nhlh2-deficient mice display growth deficiencies as adolescents and hypogonadism, hyperphagia, and obesity as adults. Nhlh2 has also been shown to promote Pcsk1 expression. Humans and mice deficient in PC1 display hyperphagic obesity, hypogonadism, decreased GH, and hypoinsulinemic diabetes due to impaired prohormone processing. Here, we found that Snord116p-/m+ mice displayed in vivo functional defects in prohormone processing of proinsulin, pro-GH-releasing hormone, and proghrelin in association with reductions in islet, hypothalamic, and stomach PC1 content. Our findings suggest that the major neuroendocrine features of PWS are due to PC1 deficiency.
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