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Physiological Reviews Jul 2018The renin-angiotensin-aldosterone system plays crucial roles in cardiovascular physiology and pathophysiology. However, many of the signaling mechanisms have been... (Review)
Review
The renin-angiotensin-aldosterone system plays crucial roles in cardiovascular physiology and pathophysiology. However, many of the signaling mechanisms have been unclear. The angiotensin II (ANG II) type 1 receptor (ATR) is believed to mediate most functions of ANG II in the system. ATR utilizes various signal transduction cascades causing hypertension, cardiovascular remodeling, and end organ damage. Moreover, functional cross-talk between ATR signaling pathways and other signaling pathways have been recognized. Accumulating evidence reveals the complexity of ANG II signal transduction in pathophysiology of the vasculature, heart, kidney, and brain, as well as several pathophysiological features, including inflammation, metabolic dysfunction, and aging. In this review, we provide a comprehensive update of the ANG II receptor signaling events and their functional significances for potential translation into therapeutic strategies. ATR remains central to the system in mediating physiological and pathophysiological functions of ANG II, and participation of specific signaling pathways becomes much clearer. There are still certain limitations and many controversies, and several noteworthy new concepts require further support. However, it is expected that rigorous translational research of the ANG II signaling pathways including those in large animals and humans will contribute to establishing effective new therapies against various diseases.
Topics: Adipocytes; Angiotensin II; Animals; Blood Vessels; Brain; Heart Diseases; Humans; Inflammation; Kidney; Kidney Diseases; Receptors, Angiotensin; Signal Transduction
PubMed: 29873596
DOI: 10.1152/physrev.00038.2017 -
Cell Apr 2017G-protein-coupled receptors (GPCRs) play critical roles in regulating physiological processes ranging from neurotransmission to cardiovascular function. Current methods...
G-protein-coupled receptors (GPCRs) play critical roles in regulating physiological processes ranging from neurotransmission to cardiovascular function. Current methods for tracking GPCR signaling suffer from low throughput, modification or overexpression of effector proteins, and low temporal resolution. Here, we show that peroxidase-catalyzed proximity labeling can be combined with isobaric tagging and mass spectrometry to enable quantitative, time-resolved measurement of GPCR agonist response in living cells. Using this technique, termed "GPCR-APEX," we track activation and internalization of the angiotensin II type 1 receptor and the β2 adrenoceptor. These receptors co-localize with a variety of G proteins even before receptor activation, and activated receptors are largely sequestered from G proteins upon internalization. Additionally, the two receptors show differing internalization kinetics, and we identify the membrane protein LMBRD2 as a potential regulator of β2 adrenoceptor signaling, underscoring the value of a dynamic view of receptor function.
Topics: Ascorbate Peroxidases; Biotin; GTP-Binding Proteins; HEK293 Cells; Humans; Oligopeptides; Protein Engineering; Receptor, Angiotensin, Type 1; Signal Transduction; Staining and Labeling; beta-Arrestins
PubMed: 28388415
DOI: 10.1016/j.cell.2017.03.028 -
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 -
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 -
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 -
Arteriosclerosis, Thrombosis, and... Apr 2019There is a complex interaction between the brain and the cerebral vasculature to meet the metabolic demands of the brain for proper function. Preservation of... (Review)
Review
There is a complex interaction between the brain and the cerebral vasculature to meet the metabolic demands of the brain for proper function. Preservation of cerebrovascular function and integrity has a central role in this sophisticated communication within the brain, and any derangements can have deleterious acute and chronic consequences. In almost all forms of cognitive impairment, from mild to Alzheimer disease, there are changes in cerebrovascular function and structure leading to decreased cerebral blood flow, which may initiate or worsen cognitive impairment. In this focused review, we discuss the contribution of 2 major vasoactive pathways to cerebrovascular dysfunction and cognitive impairment in an effort to identify early intervention strategies.
Topics: Alzheimer Disease; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Blood-Brain Barrier; Brain; Cerebrovascular Circulation; Cognition; Cognition Disorders; Disease Models, Animal; Endothelins; Endothelium, Vascular; Forecasting; Humans; Receptors, Angiotensin; Receptors, Endothelin; Renin-Angiotensin System
PubMed: 30816798
DOI: 10.1161/ATVBAHA.118.311906 -
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 -
The FEBS Journal Mar 2020Obesity is often associated with high systemic and local renin-angiotensin system (RAS) activity in adipose tissue. Adipose-derived mesenchymal stem/stromal cells... (Review)
Review
Obesity is often associated with high systemic and local renin-angiotensin system (RAS) activity in adipose tissue. Adipose-derived mesenchymal stem/stromal cells (ADSCs), responsible for adipose tissue growth upon high-fat diet, express multiple angiotensin II receptor isoforms, including angiotensin II type 1 receptor (AT R), angiotensin II type 2 receptor (AT R), Mas and Mas-related G protein-coupled receptor D. Although AT R is expressed on most ADSCs, other angiotensin receptors are co-expressed on a small subpopulation of the cells, a phenomenon that results in a complex response pattern. Following AT R activation, the effects are transient due to rapid receptor internalisation. This short-lived effect can be prevented by heteromerisation with AT R, a particularly important strategy for the regulation of ADSC differentiation and secretory activity. Heteromeric AT R might be especially important for the generation of thermogenic beige adipocytes. This review summarises current data regarding the regulation of adipose tissue renewal and particularly ADSC adipogenic differentiation and secretory activity by RAS, with an emphasis on AT R and its effects. We reveal a new scheme that implicates AT R into the regulation of ADSC hormonal sensitivity.
Topics: Adipose Tissue; Animals; Cell Proliferation; Humans; Receptor, Angiotensin, Type 2
PubMed: 31899581
DOI: 10.1111/febs.15200 -
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 -
American Journal of Physiology.... Nov 2018Cigarette smoking is the single most important risk factor for the development of cardiovascular and pulmonary diseases (CVPD). Although cigarette smoking has been in... (Review)
Review
Cigarette smoking is the single most important risk factor for the development of cardiovascular and pulmonary diseases (CVPD). Although cigarette smoking has been in constant decline since the 1950s, the introduction of e-cigarettes or electronic nicotine delivery systems 10 yr ago has attracted former smokers as well as a new generation of consumers. Nicotine is a highly addictive substance, and it is currently unclear whether e-cigarettes are "safer" than regular cigarettes or whether they have the potential to reverse the health benefits, notably on the cardiopulmonary system, acquired with the decline of tobacco smoking. Of great concern, nicotine inhalation devices are becoming popular among young adults and youths, emphasizing the need for awareness and further study of the potential cardiopulmonary risks of nicotine and associated products. This review focuses on the interaction between nicotine and the renin-angiotensin system (RAS), one of the most important regulatory systems on autonomic, cardiovascular, and pulmonary functions in both health and disease. The literature presented in this review strongly suggests that nicotine alters the homeostasis of the RAS by upregulating the detrimental angiotensin-converting enzyme (ACE)/angiotensin (ANG)-II/ANG II type 1 receptor axis and downregulating the compensatory ACE2/ANG-(1-7)/Mas receptor axis, contributing to the development of CVPD.
Topics: Animals; Humans; Nicotine; Peptidyl-Dipeptidase A; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Smoking; Tobacco Products
PubMed: 30088946
DOI: 10.1152/ajpregu.00099.2018