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Journal of the American Heart... Apr 2023The incidence of heart failure and chronic kidney disease is increasing, and many patients develop both diseases. Angiotensin receptor-neprilysin inhibitor (ARNI) is a... (Review)
Review
The incidence of heart failure and chronic kidney disease is increasing, and many patients develop both diseases. Angiotensin receptor-neprilysin inhibitor (ARNI) is a promising therapeutic candidate for both diseases. ARNI has demonstrated superior cardioprotective effects compared with renin-angiotensin system inhibitors (RAS-Is) in large clinical trials such as the PARADIGM-HF (Prospective Comparison of ARNI With ACEI [Angiotensin-Converting Enzyme Inhibitor] to Determine Impact on Global Mortality and Morbidity in Heart Failure) trial. It has also been suggested that ARNI can provide renoprotective effects beyond those of RAS-Is in patients with HF. ARNI might have beneficial effects on the kidneys because of its ability to improve cardiac function in patients with heart failure and affect renal hemodynamics by enhancing the effects of hormones such as natriuretic peptide. In contrast, in the PARADIGM-HF trial, ARNI was associated with more albuminuria compared with RAS-I; thus, it is unclear whether long-term ARNI therapy has renoprotective effects. Additionally, ARNI did not provide renoprotective effects beyond RAS-I in patients with chronic kidney disease in the UK HARP-III (United Kingdom Heart and Renal Protection-III) trial. In other words, the patient population in which ARNI is more renoprotective than RAS-I might be limited. Collectively, ARNI may have renoprotective effects in addition to cardioprotective effects, but the evidence to date is applicable only to heart failure. Theoretically, given the molecular mechanism of ARNI, it could also be renoprotective in conditions such as nephrosclerosis, which has low risks of albuminuria and reduced kidney perfusion, but the evidence for such effects is lacking. Further research is needed to clarify whether ARNI therapy is an acceptable treatment strategy for renal protection.
Topics: Humans; Valsartan; Neprilysin; Tetrazoles; Receptors, Angiotensin; Albuminuria; Angiotensin Receptor Antagonists; Drug Combinations; Heart Failure; Antihypertensive Agents; Kidney; Enzyme Inhibitors; Renal Insufficiency, Chronic; Biphenyl Compounds; Stroke Volume
PubMed: 37066800
DOI: 10.1161/JAHA.122.029565 -
JAMA Network Open Sep 2022In recent years, significant progress has been made in the pharmacologic treatment of heart failure (HF) with reduced ejection fraction (HFrEF), but there is still... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
In recent years, significant progress has been made in the pharmacologic treatment of heart failure (HF) with reduced ejection fraction (HFrEF), but there is still insufficient evidence for drug therapy for HF with preserved ejection fraction (HFpEF) and mildly reduced ejection fraction (HFmrEF).
OBJECTIVE
To compare the outcomes associated with different drug combinations for the treatment of HFpEF and HFmrEF.
DATA SOURCES
A search of the PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases was conducted for studies published from inception to October 9, 2021.
STUDY SELECTION
Randomized clinical trials on the use of angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), angiotensin receptor-neprilysin inhibitors (ARNIs), mineralocorticoid receptor antagonists (MRAs), β-blockers, and sodium-glucose cotransporter 2 (SGLT2) inhibitors for patients with HFpEF or HFmrEF.
DATA EXTRACTION AND SYNTHESIS
Data extraction and bias assessment were independently performed by 2 reviewers following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. All data for 3 outcomes were pooled with a fixed-effect model.
MAIN OUTCOMES AND MEASURES
The main outcomes were first hospitalization for HF, all-cause mortality, and cardiovascular mortality. Hazard ratios (HRs) and 95% credible intervals (CrIs) were evaluated using a bayesian network meta-analysis model.
RESULTS
In this analysis, 19 randomized clinical trials, including 20 633 patients with HF and an ejection fraction of 40% or more, without a remarkable risk of bias were included. Compared with placebo, no treatments were associated with a significant reduction in the risk of all-cause death or cardiovascular death. SGLT2 inhibitors, ARNIs, and MRAs were associated with a significant decrease in the risk of HF hospitalization compared with placebo (SGLT2 inhibitors: HR, 0.71 [95% CrI, 0.60-0.83]; ARNIs: HR, 0.76 [95% CrI, 0.61-0.95]; MRAs: HR, 0.83 [95% CrI, 0.69-0.99]), and SGLT2 inhibitors were the optimal drug class in terms of reducing the risk for HF admission. Sensitivity analysis results demonstrated a progressive decrease in the risk of HF admission and an advance in mean rank associated with the increasing use of drug classes.
CONCLUSIONS AND RELEVANCE
The findings of this study suggest that SGLT2 inhibitors were the optimal drug class for HFpEF and HFmrEF, consistent with the most recent guideline recommendation. The incremental use of combinations of SGLT2 inhibitors, ACE inhibitors or ARBs, and β-blockers may be associated with accumulative benefits in HF hospitalization rather than all-cause death among patients with HFpEF and HFmrEF.
Topics: Adrenergic beta-Antagonists; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Angiotensins; Bayes Theorem; Glucose; Heart Failure; Humans; Mineralocorticoid Receptor Antagonists; Neprilysin; Receptors, Angiotensin; Sodium; Sodium-Glucose Transporter 2; Sodium-Glucose Transporter 2 Inhibitors; Stroke Volume
PubMed: 36125813
DOI: 10.1001/jamanetworkopen.2022.31963 -
Biochemical Pharmacology Sep 2022Angiotensin-(1-9) [Ang-(1-9)] is a peptide of the non-canonical renin-angiotensin system (RAS) synthesized from angiotensin I by the monopeptidase angiotensin-converting... (Review)
Review
Angiotensin-(1-9) [Ang-(1-9)] is a peptide of the non-canonical renin-angiotensin system (RAS) synthesized from angiotensin I by the monopeptidase angiotensin-converting enzyme type 2 (ACE2). Using osmotic minipumps, infusion of Ang-(1-9) consistently reduces blood pressure in several rat hypertension models. In these animals, hypertension-induced end-organ damage is also decreased. Several pieces of evidence suggest that Ang-(1-9) is the endogenous ligand that binds and activates the type-2 angiotensin II receptor (AT2R). Activation of AT2R triggers different tissue-specific signaling pathways. This phenomenon could be explained by the ability of AT2R to form different heterodimers with other G protein-coupled receptors. Because of the antihypertensive and protective effects of AT2R activation by Ang-(1-9), associated with a short half-life of RAS peptides, several synthetic AT2R agonists have been synthesized and assayed. Some of them, particularly CGP42112, C21 and novokinin, have demonstrated antihypertensive properties. Only two synthetic AT2R agonists, C21 and LP2-3, have been tested in clinical trials, but none of them like an antihypertensive. Therefore, Ang-(1-9) is a promising antihypertensive drug that reduces hypertension-induced end-organ damage. However, further research is required to translate this finding successfully to the clinic.
Topics: Angiotensin I; Angiotensin II; Animals; Antihypertensive Agents; Hypertension; Imidazoles; Peptidyl-Dipeptidase A; Rats; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Renin-Angiotensin System; Sulfonamides; Thiophenes
PubMed: 35870482
DOI: 10.1016/j.bcp.2022.115183 -
The American Journal of Medicine Jan 2024Simultaneous initiation of quadruple therapy with angiotensin receptor-neprilysin inhibitor, beta-adrenergic receptor blocker, mineralocorticoid receptor antagonist, and... (Review)
Review
Simultaneous initiation of quadruple therapy with angiotensin receptor-neprilysin inhibitor, beta-adrenergic receptor blocker, mineralocorticoid receptor antagonist, and sodium glucose cotransporter 2 inhibitor aims at prompt improvement and prevention of readmission in patients hospitalized for heart failure with reduced ejection fraction. However, titration of quadruple therapy is time consuming. Lengthy up-titration of quadruple therapy may negate the benefit of early initiation. Quadruple therapy should start with a sodium glucose cotransporter 2 inhibition and a mineralocorticoid antagonist, as both enable safe decongestion and require minimal or no titration. Depending on the level of decongestion and clinical characteristics, patients receive an angiotensin receptor-neprilysin inhibitor or a beta-adrenergic receptor blocker to be titrated after hospital discharge. Outpatient addition of an angiotensin receptor-neprilysin inhibitor to a beta-adrenergic receptor blocker or vice versa completes the quadruple therapy scheme. By focusing on decongestion and matching intervention to patients' profile, the present therapeutic sequence allows rapid implementation of quadruple therapy at fully recommended doses.
Topics: Humans; Sodium-Glucose Transporter 2 Inhibitors; Neprilysin; Stroke Volume; Angiotensin Receptor Antagonists; Heart Failure; Anti-Arrhythmia Agents; Adrenergic beta-Antagonists; Enzyme Inhibitors; Receptors, Adrenergic, beta; Receptors, Angiotensin; Patient-Centered Care; Mineralocorticoid Receptor Antagonists
PubMed: 37838238
DOI: 10.1016/j.amjmed.2023.09.018 -
Proceedings of the National Academy of... Aug 2020There is considerable interest in developing antibodies as functional modulators of G protein-coupled receptor (GPCR) signaling for both therapeutic and research...
There is considerable interest in developing antibodies as functional modulators of G protein-coupled receptor (GPCR) signaling for both therapeutic and research applications. However, there are few antibody ligands targeting GPCRs outside of the chemokine receptor group. GPCRs are challenging targets for conventional antibody discovery methods, as many are highly conserved across species, are biochemically unstable upon purification, and possess deeply buried ligand-binding sites. Here, we describe a selection methodology to enrich for functionally modulatory antibodies using a yeast-displayed library of synthetic camelid antibody fragments called "nanobodies." Using this platform, we discovered multiple nanobodies that act as antagonists of the angiotensin II type 1 receptor (AT1R). Following angiotensin II infusion in mice, we found that an affinity matured nanobody antagonist has comparable antihypertensive activity to the angiotensin receptor blocker (ARB) losartan. The unique pharmacology and restricted biodistribution of nanobody antagonists may provide a path for treating hypertensive disorders when small-molecule drugs targeting the AT1R are contraindicated, for example, in pregnancy.
Topics: Angiotensin Receptor Antagonists; Animals; Antibody Affinity; Blood Pressure; Cell Line; Humans; Mice; Receptors, Angiotensin; Single-Domain Antibodies
PubMed: 32753386
DOI: 10.1073/pnas.2009029117 -
International Journal of Molecular... Aug 2021The renin-angiotensin-aldosterone system (RAAS) plays a major role in cardiovascular health and disease. Short-term RAAS activation controls water and salt retention and... (Review)
Review
The renin-angiotensin-aldosterone system (RAAS) plays a major role in cardiovascular health and disease. Short-term RAAS activation controls water and salt retention and causes vasoconstriction, which are beneficial for maintaining cardiac output in low blood pressure and early stage heart failure. However, prolonged RAAS activation is detrimental, leading to structural remodeling and cardiac dysfunction. Natriuretic peptides (NPs) are activated to counterbalance the effect of RAAS and sympathetic nervous system by facilitating water and salt excretion and causing vasodilation. Neprilysin is a major NP-degrading enzyme that degrades multiple vaso-modulatory substances. Although the inhibition of neprilysin alone is not sufficient to counterbalance RAAS activation in cardiovascular diseases (e.g., hypertension and heart failure), a combination of angiotensin receptor blocker and neprilysin inhibitor (ARNI) was highly effective in several clinical trials and may modulate the risk of atrial and ventricular arrhythmias. This review summarizes the possible link between ARNI and cardiac arrhythmias and discusses potential underlying mechanisms, providing novel insights about the therapeutic role and safety profile of ARNI in the cardiovascular system.
Topics: Angiotensin Receptor Antagonists; Antihypertensive Agents; Arrhythmias, Cardiac; Cardiovascular Diseases; Heart Failure; Humans; Hypertension; Natriuretic Peptides; Neprilysin; Receptors, Angiotensin; Renin-Angiotensin System; Sympathetic Nervous System; Tetrazoles
PubMed: 34445698
DOI: 10.3390/ijms22168994 -
Molecular and Cellular Endocrinology Jun 2021The most classical view of the renin-angiotensin system (RAS) emphasizes its role as an endocrine regulator of sodium balance and blood pressure. However, it has long... (Review)
Review
The most classical view of the renin-angiotensin system (RAS) emphasizes its role as an endocrine regulator of sodium balance and blood pressure. However, it has long become clear that the RAS has pleiotropic actions that contribute to organ damage, including modulation of inflammation. Angiotensin II (Ang II) activates angiotensin type 1 receptors (AT1R) to promote an inflammatory response and organ damage. This represents the pathophysiological basis for the successful use of RAS blockers to prevent and treat kidney and heart disease. However, other RAS components could have a built-in capacity to brake proinflammatory responses. Angiotensin type 2 receptor (AT2R) activation can oppose AT1R actions, such as vasodilatation, but its involvement in modulation of inflammation has not been conclusively proven. Angiotensin-converting enzyme 2 (ACE2) can process Ang II to generate angiotensin-(1-7) (Ang-(1-7)), that activates the Mas receptor to exert predominantly anti-inflammatory responses depending on the context. We now review recent advances in the understanding of the interaction of the RAS with inflammation. Specific topics in which novel information became available recently include intracellular angiotensin receptors; AT1R posttranslational modifications by tissue transglutaminase (TG2) and anti-AT1R autoimmunity; RAS modulation of lymphoid vessels and T lymphocyte responses, especially of Th17 and Treg responses; interactions with toll-like receptors (TLRs), programmed necrosis, and regulation of epigenetic modulators (e.g. microRNAs and bromodomain and extraterminal domain (BET) proteins). We additionally discuss an often overlooked effect of the RAS on inflammation which is the downregulation of anti-inflammatory factors such as klotho, peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), transient receptor potential ankyrin 1 (TRPA1), SNF-related serine/threonine-protein kinase (SNRK), serine/threonine-protein phosphatase 6 catalytic subunit (Ppp6C) and n-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP). Both transcription factors, such as nuclear factor κB (NF-κB), and epigenetic regulators, such as miRNAs are involved in downmodulation of anti-inflammatory responses. A detailed analysis of pathways and targets for downmodulation of anti-inflammatory responses constitutes a novel frontier in RAS research.
Topics: Angiotensin I; Angiotensin II; Angiotensin-Converting Enzyme 2; Animals; Autoimmunity; Blood Pressure; Gene Expression Regulation; Humans; Inflammation; Kidney; Klotho Proteins; Peptide Fragments; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Renin-Angiotensin System; Signal Transduction; T-Lymphocytes; Water-Electrolyte Balance
PubMed: 33798633
DOI: 10.1016/j.mce.2021.111254 -
The EMBO Journal Jun 2023The peptide hormone angiotensin II regulates blood pressure mainly through the type 1 angiotensin II receptor AT R and its downstream signaling proteins G and...
The peptide hormone angiotensin II regulates blood pressure mainly through the type 1 angiotensin II receptor AT R and its downstream signaling proteins G and β-arrestin. AT R blockers, clinically used as antihypertensive drugs, inhibit both signaling pathways, whereas AT R β-arrestin-biased agonists have shown great potential for the treatment of acute heart failure. Here, we present a cryo-electron microscopy (cryo-EM) structure of the human AT R in complex with a balanced agonist, Sar -AngII, and G protein at 2.9 Å resolution. This structure, together with extensive functional assays and computational modeling, reveals the molecular mechanisms for AT R signaling modulation and suggests that a major hydrogen bond network (MHN) inside the receptor serves as a key regulator of AT R signal transduction from the ligand-binding pocket to both G and β-arrestin pathways. Specifically, we found that the MHN mutations N111 A and N294 A induce biased signaling to G and β-arrestin, respectively. These insights should facilitate AT R structure-based drug discovery for the treatment of cardiovascular diseases.
Topics: Humans; Cryoelectron Microscopy; Signal Transduction; beta-Arrestins; Angiotensin II; Receptors, Angiotensin
PubMed: 37038975
DOI: 10.15252/embj.2022112940 -
Hypertension Research : Official... Jul 2022Angiotensin receptor-neprilysin inhibitors have multiple beneficial effects on the cardiovascular system. The angiotensin receptor-neprilysin inhibitor... (Review)
Review
Angiotensin receptor-neprilysin inhibitors have multiple beneficial effects on the cardiovascular system. The angiotensin receptor-neprilysin inhibitor sacubitril/valsartan has been shown to effectively reduce ambulatory 24-h blood pressure in patients with hypertension, and improvements in many aspects of hemodynamic function have also been reported. Overall hemodynamic effects on arterial stiffness and nocturnal blood pressure play an important role in the pathogenesis of hypertensive heart disease. Therefore, these could represent mechanistic targets underlying the effects of angiotensin receptor-neprilysin inhibitors on the continuum of cardiovascular disease from hypertension to heart failure. Other potential mechanisms include reductions in circulating volume and sympathetic activity, both of which contribute to the protection against target organ damage and positive changes in cardiac biomarkers seen during angiotensin receptor-neprilysin inhibitor therapy. The mechanisms of action and beneficial effects of angiotensin receptor-neprilysin inhibitors are complementary to those of a number of other treatment options for hypertension, suggesting the possibility of additive or even synergistic benefits. Based on available data, there are a number of patient groups who will benefit from antihypertensive treatment with an angiotensin receptor-neprilysin inhibitor, including those with salt-sensitive hypertension, structural hypertension, resistant hypertension, and hypertension in the presence of heart failure. Overall, angiotensin receptor-neprilysin inhibitors regulate blood pressure and pulse pressure via multiple mechanisms and provide cardiovascular protection. This provides an option for effective intervention early in the vicious cycle of elevated blood pressure and central pressures with progression toward heart failure that should help to address the growing worldwide heart failure epidemic.
Topics: Aminobutyrates; Angiotensin Receptor Antagonists; Antihypertensive Agents; Biphenyl Compounds; Drug Combinations; Heart Failure; Hemodynamics; Humans; Hypertension; Neprilysin; Receptors, Angiotensin; Tetrazoles; Valsartan
PubMed: 35501475
DOI: 10.1038/s41440-022-00923-2 -
Frontiers in Endocrinology 2022In conjunction with the endothelin (ET) type A (ETR) and type B (ETR) receptors, angiotensin (AT) type 1 (ATR) and type 2 (ATR) receptors, are peptide-binding class A... (Review)
Review
In conjunction with the endothelin (ET) type A (ETR) and type B (ETR) receptors, angiotensin (AT) type 1 (ATR) and type 2 (ATR) receptors, are peptide-binding class A G-protein-coupled receptors (GPCRs) acting in a physiologically overlapping context. Angiotensin receptors (ATRs) are involved in regulating cell proliferation, as well as cardiovascular, renal, neurological, and endothelial functions. They are important therapeutic targets for several diseases or pathological conditions, such as hypertrophy, vascular inflammation, atherosclerosis, angiogenesis, and cancer. Endothelin receptors (ETRs) are expressed primarily in blood vessels, but also in the central nervous system or epithelial cells. They regulate blood pressure and cardiovascular homeostasis. Pathogenic conditions associated with ETR dysfunctions include cancer and pulmonary hypertension. While both receptor groups are activated by their respective peptide agonists, pathogenic autoantibodies (auto-Abs) can also activate the ATR and ETR accompanied by respective clinical conditions. To date, the exact mechanisms and differences in binding and receptor-activation mediated by auto-Abs as opposed to endogenous ligands are not well understood. Further, several questions regarding signaling regulation in these receptors remain open. In the last decade, several receptor structures in the apo- and ligand-bound states were determined with protein X-ray crystallography using conventional synchrotrons or X-ray Free-Electron Lasers (XFEL). These inactive and active complexes provide detailed information on ligand binding, signal induction or inhibition, as well as signal transduction, which is fundamental for understanding properties of different activity states. They are also supportive in the development of pharmacological strategies against dysfunctions at the receptors or in the associated signaling axis. Here, we summarize current structural information for the ATR, ATR, and ETR to provide an improved molecular understanding.
Topics: Angiotensins; Ligands; Receptor, Angiotensin, Type 1; Receptor, Endothelin A; Signal Transduction
PubMed: 35518926
DOI: 10.3389/fendo.2022.880002