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36
result(s) for
"Angiotensin modulators"
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RAS modulation prevents progressive cognitive impairment after experimental stroke: a randomized, blinded preclinical trial
by
Fouda, Abdelrahman Y.
,
Pillai, Bindu
,
Ahmed, Heba A.
in
Aging
,
Alzheimer's disease
,
Amyloid beta-Peptides - pharmacology
2018
Background
With the aging population, the prevalence and incidence of cerebrovascular disease will continue to rise, as well as the number of individuals with vascular cognitive impairment/dementia (VCID). No specific FDA-approved treatments for VCID exist. Although clinical evidence supports that angiotensin receptor blockers (ARBs) prevent cognitive decline in older adults, whether ARBs have a similar effect on VCID after stroke is unknown. Moreover, these agents reduce BP, which is undesirable in the acute stroke period, so we believe that giving C21 in this acute phase or delaying ARB administration would enable us to achieve the neurovascular benefits without the risk of unintended and potentially dangerous, acute BP lowering.
Methods
The aim of our study was to determine the impact of candesartan (ARB) or compound-21 (an angiotensin type 2 receptor––AT2R––agonist) on long-term cognitive function post-stroke, in spontaneously hypertensive rats (SHRs). We hypothesized that AT2R stimulation, either directly with C21, or indirectly by blocking the angiotensin type 1 receptor (AT1R) with candesartan, initiated after stroke, would reduce cognitive impairment. Animals were subjected to a 60-min transient middle cerebral artery occlusion and randomly assigned to either saline/C21 monotherapy, for the full study duration (30 days), or given sequential therapy starting with saline/C21 (7 days) followed by candesartan for the remainder of the study (21 days). Outcome measures included sensorimotor/cognitive-function, amyloid-β determination, and histopathologic analyses.
Results
Treatment with RAS modulators effectively preserved cognitive function, reduced cytotoxicity, and prevented chronic-reactive microgliosis in SHRs, post-stroke. These protective effects were apparent even when treatment was delayed up to 7 days post-stroke and were independent of blood pressure and β-amyloid accumulation.
Conclusion
Collectively, our findings demonstrate that RAS modulators effectively prevent cognitive impairment after stroke, even when treatment is delayed.
Journal Article
The Brain AT2R—a Potential Target for Therapy in Alzheimer’s Disease and Vascular Cognitive Impairment: a Comprehensive Review of Clinical and Experimental Therapeutics
2020
Dementia is a potentially avertable tragedy, currently considered among the top 10 greatest global health challenges of the twenty-first century. Dementia not only robs individuals of their dignity and independence, it also has a ripple effect that starts with the inflicted individual’s family and projects to the society as a whole. The constantly growing number of cases, along with the lack of effective treatments and socioeconomic impact, poses a serious threat to the sustainability of our health care system. Hence, there is a worldwide effort to identify new targets for the treatment of Alzheimer’s disease (AD), the leading cause of dementia. Due to its multifactorial etiology and the recent clinical failure of several novel amyloid-β (Aβ) targeting therapies, a comprehensive “multitarget” approach may be most appropriate for managing this condition. Interestingly, renin angiotensin system (RAS) modulators were shown to positively impact all the factors involved in the pathophysiology of dementia including vascular dysfunction, Aβ accumulation, and associated cholinergic deficiency, in addition to tau hyperphosphorylation and insulin derangements. Furthermore, for many of these drugs, the preclinical evidence is also supported by epidemiological data and/or preliminary clinical trials. The purpose of this review is to provide a comprehensive update on the major causes of dementia including the risk factors, current diagnostic criteria, pathophysiology, and contemporary treatment strategies. Moreover, we highlight the angiotensin II receptor type 2 (AT2R) as an effective drug target and present ample evidence supporting its potential role and clinical applications in cognitive impairment to encourage further investigation in the clinical setting.
Journal Article
Patterns of use and dose optimization of renin-angiotensin system modulators among chronic heart failure patients with reduced ejection fraction in resource-limited settings: a multicenter cohort study
by
Wondm, Samuel Agegnew
,
Anberbr, Sisay Sitotaw
,
Ayele, Teklie Mengie
in
Cohort analysis
,
Drug dosages
,
Ejection fraction
2025
Background:
Optimal use of renin-angiotensin system (RAS) modulators plays a crucial role in improving the outcomes for chronic heart failure (CHF) patients with reduced ejection fraction (rEF). Despite their established benefits, there is limited evidence regarding real-world prescribing patterns, dose optimization, and factors influencing RAS modulator use in this population.
Objective:
This study aimed to evaluate the patterns of use, dose optimization, and associated factors affecting the administration of RAS modulators among CHF patients with rEF at Public Comprehensive Specialized Hospitals (PCSHs).
Design:
A hospital-based, multicenter cohort study was conducted from February 1, 2020, to May 31, 2024, at PCSHs among CHF patients with rEF.
Methods:
A total sample size of 385 patients was determined using a systematic random sampling technique at the Northwest Ethiopian PCSHs during the study period. Data were collected from medical records and interviews using standardized questionnaires. Data analysis was performed using SPSS version 27.0, and binary logistic regression analysis was employed to identify factors associated with the use and optimization of RAS modulators. The study strictly adhered to the most recent guideline recommendations from the American Heart Association (2022) and the European Society of Cardiology (2021).
Results:
Of 385 patients, 263 (68.3%) were prescribed RAS modulators; however, only 86 (32.7%) of these patients were receiving an optimal dose. Predictors significantly associated with the use of RAS modulators included a duration of CHF with rEF of ⩾3 years (AOR: 1.79, 95% CI: 1.02–3.15), the presence of ischemic heart disease (AOR: 8.23, 95% CI: 4.23–16), hypertension (AOR: 2, 95% CI: 1.09–3.69), diabetes mellitus (AOR: 7.34, 95% CI: 1.48–36.34), chronic kidney disease (AOR: 4.35, 95% CI: 1.32–14.34), and a furosemide dose of ⩾40 mg (AOR: 0.26, 95% CI: 0.013–0.49). Regarding suboptimal RAS modulator dosing, significant predictors identified were age ⩾65 years (AOR: 2.83, 95% CI: 1.46–5.50), a previous history of hospitalization (AOR: 2.05, 95% CI: 1.07–3.95), the use of diuretics (AOR: 5.34, 95% CI: 2.73–10.44), a furosemide dose of ⩾40 mg (AOR: 3.88, 95% CI: 1.89–7.97), and CHF with rEF for ⩾3 years (AOR: 0.31, 95% CI: 0.16–0.63).
Conclusions:
The majority of CHF patients with rEF received suboptimal doses of RAS modulators, with only one-third receiving optimal therapy. This highlights a critical gap in treatment that must be urgently addressed. Targeted interventions are needed to identify and mitigate modifiable predictors contributing to suboptimal dosing, thereby improving therapeutic outcomes and reducing the burden of CHF with rEF.
Journal Article
Activation pathway of a G protein-coupled receptor uncovers conformational intermediates as targets for allosteric drug design
2021
G protein-coupled receptors (GPCRs) are the most common proteins targeted by approved drugs. A complete mechanistic elucidation of large-scale conformational transitions underlying the activation mechanisms of GPCRs is of critical importance for therapeutic drug development. Here, we apply a combined computational and experimental framework integrating extensive molecular dynamics simulations, Markov state models, site-directed mutagenesis, and conformational biosensors to investigate the conformational landscape of the angiotensin II (AngII) type 1 receptor (AT
1
receptor) — a prototypical class A GPCR—activation. Our findings suggest a synergistic transition mechanism for AT
1
receptor activation. A key intermediate state is identified in the activation pathway, which possesses a cryptic binding site within the intracellular region of the receptor. Mutation of this cryptic site prevents activation of the downstream G protein signaling and β-arrestin-mediated pathways by the endogenous AngII octapeptide agonist, suggesting an allosteric regulatory mechanism. Together, these findings provide a deeper understanding of AT
1
receptor activation at an atomic level and suggest avenues for the design of allosteric AT
1
receptor modulators with a broad range of applications in GPCR biology, biophysics, and medicinal chemistry.
G protein-coupled receptors (GPCRs) are a critical target in modern drug development across a wide range of indications. Here the authors provide a comprehensive characterization of a typical GPCR, the angiotensin II (AngII) type 1 receptor (AT1R), and provide insight into its activation mechanism that suggest avenues for the design of allosteric GPCR modulators.
Journal Article
Synthetic nanobodies as angiotensin receptor blockers
by
Elgeti, Matthias
,
Staus, Dean P.
,
Hubbell, Wayne L.
in
Angiotensin AT1 receptors
,
Angiotensin II
,
Angiotensin Receptor Antagonists
2020
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.
Journal Article
In vitro and in vivo identification of clinically approved drugs that modify ACE2 expression
by
Aldape, Kenneth
,
Schiff, Eyal
,
Cheng, Kuoyuan
in
ACE2
,
angiotensin I‐converting enzyme 2
,
Angiotensin-converting enzyme 2
2020
The COVID‐19 pandemic caused by SARS‐CoV‐2 has been a global health challenge. Angiotensin‐converting enzyme 2 (
ACE
2
) is the host receptor for SARS‐CoV‐2 entry. Recent studies have suggested that patients with hypertension and diabetes treated with ACE inhibitors (ACEIs) or angiotensin receptor blockers have a higher risk of COVID‐19 infection as these drugs could upregulate
ACE
2
, motivating the study of
ACE
2
modulation by drugs in current clinical use. Here, we mined published datasets to determine the effects of hundreds of clinically approved drugs on
ACE
2
expression. We find that ACEIs are enriched for
ACE
2
‐upregulating drugs, while antineoplastic agents are enriched for
ACE
2
‐downregulating drugs. Vorinostat and isotretinoin are the top
ACE
2
up/downregulators, respectively, in cell lines. Dexamethasone, a corticosteroid used in treating severe acute respiratory syndrome and COVID‐19, significantly upregulates
ACE
2
both
in vitro
and
in vivo
. Further top
ACE
2
regulators
in vivo
or in primary cells include erlotinib and bleomycin in the lung and vancomycin, cisplatin, and probenecid in the kidney. Our study provides leads for future work studying
ACE
2
expression modulators.
Synopsis
Analyzing large‐scale
in vitro
and
in vivo
publicly available transcriptomic data of drug treatments, we identify the effects of hundreds of clinically approved drugs on expression of
ACE2
, the host receptor of SARS‐CoV‐2.
ACE inhibitors are enriched for
ACE2
‐upregulating drugs among antihypertensives, while antineoplastic agents are enriched for
ACE2
‐down-regulating drugs.
Dexamethasone significantly upregulates
ACE2
both
in vitro
and
in vivo
.
Additionally, the top ranked up‐regulators include vorinostat, erlotinib and vancomycin; top down‐regulators include isotretinoin, bleomycin and probenecid.
Graphical Abstract
Analyzing large‐scale
in vitro
and
in vivo
publicly available transcriptomic data of drug treatments, we identify the effects of hundreds of clinically approved drugs on expression of
ACE2
, the host receptor of SARS‐CoV‐2.
Journal Article
Chronic kidney disease
by
Kalantar-Zadeh, Kamyar
,
Jafar, Tazeen H
,
Nitsch, Dorothea
in
Aldosterone
,
Angiotensin
,
Blood pressure
2021
Chronic kidney disease is a progressive disease with no cure and high morbidity and mortality that occurs commonly in the general adult population, especially in people with diabetes and hypertension. Preservation of kidney function can improve outcomes and can be achieved through non-pharmacological strategies (eg, dietary and lifestyle adjustments) and chronic kidney disease-targeted and kidney disease-specific pharmacological interventions. A plant-dominant, low-protein, and low-salt diet might help to mitigate glomerular hyperfiltration and preserve renal function for longer, possibly while also leading to favourable alterations in acid-base homoeostasis and in the gut microbiome. Pharmacotherapies that alter intrarenal haemodynamics (eg, renin–angiotensin–aldosterone pathway modulators and SGLT2 [SLC5A2] inhibitors) can preserve kidney function by reducing intraglomerular pressure independently of blood pressure and glucose control, whereas other novel agents (eg, non-steroidal mineralocorticoid receptor antagonists) might protect the kidney through anti-inflammatory or antifibrotic mechanisms. Some glomerular and cystic kidney diseases might benefit from disease-specific therapies. Managing chronic kidney disease-associated cardiovascular risk, minimising the risk of infection, and preventing acute kidney injury are crucial interventions for these patients, given the high burden of complications, associated morbidity and mortality, and the role of non-conventional risk factors in chronic kidney disease. When renal replacement therapy becomes inevitable, an incremental transition to dialysis can be considered and has been proposed to possibly preserve residual kidney function longer. There are similarities and distinctions between kidney-preserving care and supportive care. Additional studies of dietary and pharmacological interventions and development of innovative strategies are necessary to ensure optimal kidney-preserving care and to achieve greater longevity and better health-related quality of life for these patients.
Journal Article
Renin-angiotensin system modulators and other risk factors in COVID-19 patients with hypertension: a Korean perspective
by
Kang, Minseok
,
Kim, Hee-Sung
,
Kang, Gilwon
in
Aged
,
Angiotensin
,
Angiotensin converting enzyme inhibitor (ACEI)
2021
Background
While hypertension is the most common comorbid condition in patients with coronavirus disease 2019 (COVID-19) in Korea, there is a lack of studies investigating risk factors in COVID-19 patients with hypertension in Korea. In this study, we aimed to examine the effects risk factors in hypertensive Korean COVID-19 patients.
Methods
We selected patients from the database of the project #OpenData4Covid19. This information was linked to their 3-year historical healthcare data. The severity of the disease was classified into five levels. We also clustered the levels into two grades.
Results
The risk factors associated with COVID-19 severity were old age, diabetes mellitus, cerebrovascular disease, chronic obstructive pulmonary disease (COPD), malignancy, and renal replacement therapy. The use of angiotensin converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) both before and after a diagnosis of COVID-19 were not associated with COVID-19 severity. A multivariate analysis revealed that old age, male sex, diabetes mellitus, and renal replacement therapy were risk factors for severe COVID-19.
Conclusion
The results suggest that in hypertensive patients with COVID-19, older age, male sex, a diagnosis of diabetes mellitus, and renal replacement therapy were risk factors for a severe clinical course. In addition, the use of ARBs and ACEIs before or after COVID-19 infection did not affect a patient’s risk of contracting COVID-19 nor did it contribute to a worse prognosis for the disease. These results highlighted that precautions should be considered for hypertensive patients with those risk factors and do not support discontinuation of ARBs and ACEIs during COVID-19 pandemic.
Journal Article
Angiotensin II receptor blocker intake associates with reduced markers of inflammatory activation and decreased mortality in patients with cardiovascular comorbidities and COVID-19 disease
2021
We analyzed 1946 consecutive patients with cardiovascular comorbidities or hypertension enrolled in one of the largest European COVID-19 registries, the Lean European Open Survey on SARS-CoV-2 (LEOSS) registry. Here, we show that angiotensin II receptor blocker intake is associated with decreased mortality in patients with COVID-19 [OR 0.75 (95% CI 0,59-0.96; p = 0.013)]. This effect was mainly driven by patients, who presented in an early phase of COVID-19 at baseline [OR 0,64 (95% CI 0,43-0,96; p = 0.029)]. Kaplan-Meier analysis revealed a significantly lower incidence of death in patients on an angiotensin receptor blocker (ARB) (n = 33/318;10,4%) compared to patients using an angiotensin-converting enzyme inhibitor (ACEi) (n = 60/348;17,2%) or patients who received neither an ACE-inhibitor nor an ARB at baseline in the uncomplicated phase (n = 90/466; 19,3%; p<0.034). Patients taking an ARB were significantly less frequently reaching the mortality predicting threshold for leukocytes (p<0.001), neutrophils (p = 0.002) and the inflammatory markers CRP (p = 0.021), procalcitonin (p = 0.001) and IL-6 (p = 0.049). ACE2 expression levels in human lung samples were not altered in patients taking RAAS modulators. These data suggest a beneficial effect of ARBs on disease severity in patients with cardiovascular comorbidities and COVID-19, which is linked to dampened systemic inflammatory activity.
Journal Article
Effect of selective BET protein inhibitor apabetalone on cardiovascular outcomes in patients with acute coronary syndrome and diabetes: Rationale, design, and baseline characteristics of the BETonMACE trial
by
Schwartz, Gregory G.
,
Nicholls, Stephen J.
,
Toth, Peter P.
in
Acute Coronary Syndrome - blood
,
Acute Coronary Syndrome - drug therapy
,
Acute Coronary Syndrome - mortality
2019
After an acute coronary syndrome (ACS), patients with diabetes remain at high risk for additional cardiovascular events despite use of current therapies. Bromodomain and extra-terminal (BET) proteins are epigenetic modulators of inflammation, thrombogenesis, and lipoprotein metabolism implicated in atherothrombosis. The BETonMACE trial tests the hypothesis that treatment with apabetalone, a selective BET protein inhibitor, will improve cardiovascular outcomes in patients with diabetes after an ACS.
Patients (n = 2425) with ACS in the preceding 7 to 90 days, with type 2 diabetes and low HDL cholesterol (≤40 mg/dl for men, ≤45 mg/dl for women), receiving intensive or maximum-tolerated therapy with atorvastatin or rosuvastatin, were assigned in double-blind fashion to receive apabetalone 100 mg orally twice daily or matching placebo. Baseline characteristics include female sex (25%), myocardial infarction as index ACS event (74%), coronary revascularization for index ACS (80%), treatment with dual anti-platelet therapy (87%) and renin-angiotensin system inhibitors (91%), median LDL cholesterol 65 mg per deciliter, and median HbA1c 7.3%. The primary efficacy measure is time to first occurrence of cardiovascular death, non-fatal myocardial infarction, or stroke. Assumptions include a primary event rate of 7% per annum in the placebo group and median follow-up of 1.5 years. Patients will be followed until at least 250 primary endpoint events have occurred, providing 80% power to detect a 30% reduction in the primary endpoint with apabetalone.
BETonMACE will determine whether the addition of the selective BET protein inhibitor apabetalone to contemporary standard of care for ACS reduces cardiovascular morbidity and mortality in patients with type 2 diabetes. Results are expected in 2019.
Journal Article