Mineralocorticoid Receptor Research Articles

Clinical significance of normohydration state in peritoneal dialysis patients

Introduction: Assessing the fluid status of dialysis patients is crucial, as overhydration can lead to hypertension and left ventricular hypertrophy. Objectives: We aimed to determine the hydration of peritoneal dialysis (PD) patients by using a bioimpedance device and performing concomitant echocardiographic measurements. Patients and Methods: In our cohort, we enrolled PD patients in the study group and kidney transplantation waitlisted patients on hemodialysis (HD) or with stage 4-5 chronic kidney disease (CKD) in the control group. Fluid status was measured with a Fresenius Body Composition Monitor (BCM), and we performed an echocardiography examination. For statistical analysis, we used the Fisher’s exact test for categorical variables and the Kruskal-Wallis test for continuous variables to compare groups. Results: The patients’ average age was 47 (SD 9.45), with a mild female predominance (54.3%). Overhydration was only found in 8 (12%) patients and was related to non-significantly lower ejection fraction (EF). Follow-up found that preserved EF was a non-significantly better outcome (HR: 0.881, 95% CI interval: 0.776; 1.001, P=0.0514). PD patients had significantly lower potassium levels (P=0.0006) and more angiotensin-converting-enzyme inhibitors (ACEis) (46%) and mineralocorticoid receptor antagonists (MRAs) (26%). Conclusion: Lower potassium levels in continuous ambulatory peritoneal dialysis (CAPD) patients allow for the administration of drugs to treat cardiac remodeling and volume overload, which can help reduce patient mortality. The possible usage of MRAs in CKD could reduce cardiovascular mortality effectively.

Insights on prevalence and incidence of anemia and rapid up-titration of oral heart failure treatment from the STRONG-HF study.

Anemia is one of the most frequent comorbidities in patients with heart failure (HF), which potentially can interfere with the effect of guideline-recommended HF medical therapy and can be associated with the use of neurohormonal blockers. The aim of this analysis was to determine the prevalence and changes of anemia status in the STRONG-HF study, its association with clinical endpoints, and possible interaction of the presence of anemia with the efficacy and safety of high-intensity HF treatment. The design and main results of the study have been previously described. Patients were randomized within 2days prior to anticipated hospital discharge after HF worsening in a 1:1 fashion to either high-intensity care (HIC) or usual care (UC). Baseline characteristics, clinical and safety outcomes, and treatment effect of HIC vs. UC on the primary and secondary outcomes were compared in groups based on baseline anemia. In addition, dynamics of hemoglobin during the study follow-up and predictors of incident anemia at 90days were investigated. The proportion of anemia in 1077 STRONG-HF patients at enrollment was 27.2%, while at 90days, it changed to 32.1%. The primary composite outcome occurred in 18.2% of patients without baseline anemia, and 22.5% of patients with baseline anemia (unadjusted HR 1.27; 95% CI 0.90-1.80), a difference that did not reach statistical significance. However, patients with baseline anemia had significantly less improvement of EQ-VAS questionnaire values from baseline to day 90 (adjusted LS-Mean difference -2.34 (-4.37, -0.31), P = 0.02). During the study, anemia developed in 19.4 and 14.6% in HIC and UC groups, respectively. The opposite phenomenon-recovery of anemia-occurred in 27.6 and 28.8% in HIC and UC groups (P = 0.1379). The predictors of incident anemia at 90days were male sex, geographical region other than Europe, ischemic etiology, higher glucose, and elevated uric acid at baseline. The percentages of optimal doses of renin-angiotensin system inhibitors, beta-blockers, and mineralocorticoid receptor antagonists were not different between anemic and non-anemic patients. High-intensity care strategy did not increase rate of incident anemia at 90days and reduced the rate of primary and secondary endpoints regardless of baseline hemoglobin. Hemoglobin level and status of anemia have a dynamic nature in the acute HF patients in the post-discharge period dependent on multiple factors. High-intensity HF treatment is safe and beneficial regardless of baseline hemoglobin level and presence of anemia. The improvement of quality of life is significantly lower in anemic HF patients implying specific attention to correction of this condition.

Heart failure in Europe: Guideline-directed medical therapy use and decision making in chronic and acute, pre-existing and de novo, heart failure with reduced, mildly reduced, and preserved ejection fraction-the ESC EORP Heart Failure III Registry.

We analysed baseline characteristics and guideline-directed medical therapy (GDMT) use and decisions in the European Society of Cardiology (ESC) Heart Failure (HF) III Registry. Between 1 November 2018 and 31 December 2020, 10 162 patients with acute HF (AHF, 39%, age 70 [62-79], 36% women) or outpatient visit for HF (61%, age 66 [58-75], 33% women), with HF with reduced (HFrEF, 57%), mildly reduced (HFmrEF, 17%) or preserved (HFpEF, 26%) ejection fraction were enrolled from 220 centres in 41 European or ESC-affiliated countries. With AHF, 97% were hospitalized, 2.2% received intravenous treatment in the emergency department, and 0.9% received intravenous treatment in an outpatient clinic. AHF was seen by most by a general cardiologist (51%) and outpatient HF most by a HF specialist (48%). A majority had been hospitalized for HF before, but 26% of AHF and 6.1% of outpatient HF had de novo HF. Baseline use, initiation and discontinuation of GDMT varied according to AHF versus outpatient HF, de novo versus pre-existing HF, and by ejection fraction. After the AHF event or outpatient HF visit, use of any renin-angiotensin system inhibitor, angiotensin receptor-neprilysin inhibitor, beta-blocker, mineralocorticoid receptor antagonist and loop diuretics was 89%, 29%, 92%, 78%, and 85% in HFrEF; 89%, 9.7%, 90%, 64%, and 81% in HFmrEF; and 77%, 3.1%, 80%, 48%, and 80% in HFpEF. Use and initiation of GDMT was high in cardiology centres in Europe, compared to previous reports from cohorts and registries including more primary care and general medicine and regions more local or outside of Europe and ESC-affiliated countries.

Mineralocorticoid Receptor Blocker Prevents Mineralocorticoid Receptor-Mediated Inflammation by Modulating Transcriptional Activity of Mineralocorticoid Receptor-p65-Signal Transducer and Activator of Transcription 3 Complex.

Mineralocorticoid receptor (MR) induces cardiac inflammation cooperatively with nuclear factor-κB and signal transducer and activator of transcription 3 (STAT3); MR blockers exert anti-inflammatory effects. However, the underlying mechanism remains unclear. We investigated the anti-inflammatory effect of esaxerenone, a novel MR blocker, in experimental myocardial infarction (MI) and its underlying mechanisms. Male C57BL/6J mice subjected to ligation of the left anterior descending artery were randomly assigned to either the vehicle or esaxerenone group. Esaxerenone was provided with a regular chow diet. The mice were euthanizedat either 4 or 15 days after MI. Cardiac function, fibrosis, and inflammation were evaluated. Esaxerenone significantly improved cardiac function and attenuated cardiac fibrosis at 15 days after MI independently of its antihypertensive effect. Inflammatory cell infiltration, inflammatory-related gene expression, and elevated serum interleukin-6 levels at 4 days after MI were significantly attenuated by esaxerenone. Invitro experiments using mouse macrophage-like cell line RAW264.7 cells demonstrated that esaxerenone- and spironolactone-attenuated lipopolysaccharide-induced interleukin-6 expression without altering the posttranslational modification and nuclear translocation of p65 and STAT3. Immunoprecipitation assays revealed that MR interacted with both p65 and STAT3 and enhanced the p65-STAT3 interaction, leading to a subsequent increase in interleukin-6 promoter activity, which was reversed by esaxerenone. Esaxerenone ameliorated postinfarct remodeling in experimental MI through its anti-inflammatory properties exerted by modulating the transcriptional activity of the MR-p65-STAT3 complex. These results suggest that the MR-p65-STAT3 complex can be a novel therapeutic target for treating MI.

Acute stress and blockade of mineralocorticoid or glucocorticoid receptors: Effects on working memory

Although early studies were able to demonstrate a negative impact of stress on working memory performance, present research findings are heterogeneous. Numerous further studies found no effects or even improved performance, with the direction of these stress effects likely depending on the underlying biological mechanisms. The aim of this study was to investigate receptor-specific effects, as part of the stress-induced cortisol response, on working memory performance. Healthy, male participants (N=318, mean age 25.4 ± 5.1y) were exposed to the Trier Social Stress Test (TSST), a social-evaluative stress manipulation, or a non-stress control condition after they had received either spironolactone (blockade of the mineralocorticoid receptor, MR) or mifepristone (blockade of the glucocorticoid receptor, GR) or a placebo. Both substances are potent antagonists with high affinity for the respective receptors. To assess working memory, we implemented the n-back task subsequent to stress exposure, number of correct responses and reaction times served as outcome measures. We did not find effects of stress on working memory for any outcome measure, i.e. correct responses and reaction times. Yet, post hoc tests revealed that the group that received mifepristone exhibited longer reaction times under medium load conditions when compared to the placebo group, which might be an indication of the GR’s involvement in task performance. We conclude that working memory performance is not affected by acute stress, at least under these prevalent conditions.

Retrospective study of the efficacy of methylprednisolone vs. triamcinolone in lumbar epidural steroid injections for the treatment of low back pain due to degenerative disc disease

ObjectiveA common low back pain treatment is epidural injection of corticosteroids. The nominal target of anti-inflammatory corticosteroid drugs is the glucocorticoid receptor (GR). In vitro studies show many clinically used steroids also activate the mineralocorticoid receptor (MR) with substantial potency. Based on preclinical studies, this may have pro-inflammatory and pro-nociceptive effects that counter the desired GR effects. Of two outpatient pain clinics associated with the University of Cincinnati Department of Anesthesiology, one primarily used methylprednisolone while the other used mainly triamcinolone for epidural steroid injections. We hypothesized that triamcinolone would give better outcomes because in vitro, ratio of MR/GR potency is about 10 fold less favorable for methylprednisolone.MethodsWe conducted a retrospective chart review of adults receiving lumbar epidural steroid injection for low back pain due to degenerative disc disease at the two pain clinics. For subjects treated at the first clinic, we obtained basic demographics, smoking history, 2 primary outcomes (patient-rated percent improvement in pain levels, and injection outcome rated as poor, partial, or good), and pain ratings (0–10 scale) before and after injection. For analysis, a subset of subjects from the second clinic was matched as closely as possible (sex, age, race, and ethnicity) to those from the first clinic.ResultsEighty-six subjects from the first clinic were identified, of whom fifty-five met inclusion criteria. Review of 83 potentially matched subjects from the second clinic yielded 37 subjects. From this combined set of subjects, 44 receiving triamcinolone and 48 receiving methylprednisolone were obtained. Matching was effective in avoiding significant differences between the two drug groups in age, weight, sex, race, and body mass index, however, the incidence of smoking (current and former) was significantly higher in the methylprednisolone group (who were primarily from clinic 1). The injection responses codified on a 0–2 scale, where 0 indicated a poor response, 1 a partial response with a second injection recommended, and 2 a good response where no further treatment was recommended at the 1 month follow up point, were not significantly different between the groups (Mann–Whitney, p = 0.44) although the triamcinolone group overall had slightly better responses. However, the patient-reported percent improvement after the injection was significantly better for the triamcinolone than for methylprednisolone (60% ± 5.3 vs. 42% ± 4.9), as was the pain ratings (0–10 scale) after the injection (5.0 ± 0.5 vs. 6.3 ± 0.3). A marked demographic difference between the two clinics in smoking rates was not controlled for in subject matching but accounting for smoking status did not affect the observed differences between the two steroids.ConclusionsDifferences in the two primary outcomes, patient-reported percent improvement and pain ratings after epidural steroid injection, were consistent with the hypothesis that more GR-selective steroids may give better outcomes though the differences were modest. We propose that one factor in choosing steroids should be their relative potency in also activating the pro-inflammatory mineralocorticoid receptor.Graphical

Looking for the ideal medication for heart failure with reduced ejection fraction: a narrative review.

The main goals of the pharmacological treatment of Heart failure with reduced ejection fraction (HFrEF) are the reduction of mortality and the prevention of hospitalizations. However, other outcomes such as improvements in cardiac remodeling and clinical status, functional capacity and quality of life, should be taken into account. Also, given the significant inter-individual and intra-individual variability of HF, and the fact that patients usually present with comorbidities, an appropriate treatment for HFrEF should exert a clinical benefit in most patient profiles irrespective of their characteristics or the presence of comorbidities, while providing organ protection beyond the cardiovascular system. The aim of this narrative review is to determine which are the proven effects of the guideline-directed treatments for HFrEF on five key clinical outcomes: cardiovascular mortality and hospitalization due to HF, sudden death, reverse cardiac remodeling, renal protection and evidence in hospitalized patients. Publications that fulfilled the pre-established selection criteria were selected and reviewed. Renin-angiotensin system (RAS) inhibitors, namely angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARBs) or angiotensin receptor-neprilysin inhibitors (ARNI), beta-blockers (BB), mineralocorticoid receptor antagonists (MRA), sodium-glucose co-transporter 2 inhibitors (SGLT2i) show a benefit in terms of mortality and hospitalization rates. ARNI, BB, and MRA have demonstrated a significant positive effect on the incidence of sudden death. ARB, ARNI, BB and SGLT2i have been associated with clear benefits in reverse cardiac remodeling. Additionally, there is consistent evidence of renal protection from ARB, ARNI, and SGLT2i in renal protection and of benefits for hospitalized patients from ARNI and SGLT2i. In conclusion, the combination of drugs that gather most beneficial effects in HFrEF, beyond cardiovascular mortality and hospitalization, would be ideally pursued.

Cardiovascular and all-cause mortality outcomes of adrenalectomy versus medical treatment in primary aldosteronism: an umbrella review.

Primary aldosteronism (PA) is now recognized as the most prevalent form of secondary hypertension globally, contributing significantly to cardiovascular morbidity and mortality. This umbrella review aims to systematically compare cardiovascular outcomes and all-cause mortality in PA patients undergoing adrenalectomy versus mineralocorticoid receptor antagonist (MRA) treatment, aiming to inform optimal management strategies. Following PRISMA guidelines, Supplemental Digital Content 1, http://links.lww.com/JS9/D386, Supplemental Digital Content 2, http://links.lww.com/JS9/D387, a comprehensive search strategy was employed across multiple databases. Meta-analyses focusing on cardiovascular outcomes or all-cause mortality, comparing adrenalectomy and MRAs treatment in PA patients, were included. Studies were independently screened and assessed for quality using AMSTAR 2, Supplemental Digital Content 3, http://links.lww.com/JS9/D388 and GRADE checklists. A total of 8 studies met the inclusion criteria. Adrenalectomy showed potential benefits over MRAs in reducing the risk of arrhythmias (OR=2.17; 95% CI: 1.25-3.76) and major adverse cardiovascular events (OR=1.81; 95% CI: 1.33-2.46). Patients treated with MRAs exhibited a higher risk of cardiovascular events (OR=1.23; 95% CI: 1.05-1.44), hypertension (OR=3.22; 95% CI: 1.15-8.97), and all-cause mortality (OR=3.03; 95% CI: 1.36-6.70) compared to adrenalectomy. Adrenalectomy appears to offer favorable outcomes compared to MRAs treatment in PA patients, particularly in reducing the risk of major adverse cardiovascular events and all-cause mortality. These findings suggest the importance of considering surgical intervention as a primary treatment modality for PA.

Factors Associated With Sacubitril/Valsartan Continuation and the Methods of Combining Heart Failure Medications in Patients With Heart Failure.

Sacubitril/valsartan (SV) is recommended for patients with heart failure (HF). In addition, a combination of 4 HF medications, including SV, is recommended in patients with HF with reduced ejection fraction (HFrEF). However, evidence on the characteristics of patients who could continue SV and its initiation methods is limited. To investigate the factors associated with SV continuation and methods of combining HF medications. This retrospective cohort study included HF patients who initiated with SV at our institution. The endpoint was SV continuation for 6 months after its initiation. Multivariate analysis was used to extract factors associated with SV continuation. The relationship between the methods of combining HF medications (renin-angiotensin system inhibitors, beta-blockers, mineralocorticoid receptor antagonists, or sodium-glucose cotransporter 2 inhibitors), including the number of HF medications, their combination patterns, and the timing of their initiation, and SV continuation was examined in patients with HFrEF. Of 186 eligible patients, 68.8% had HFrEF, and 79.0% continued SV for 6 months. Significant factors associated with SV continuation were albumin ≥ 3.5 g/dL (odds ratio, 4.81; 95% confidence interval, 2.19-10.59), body mass index (BMI) ≥ 18.5 kg/m2 (4.17; 1.10-15.85), and systolic blood pressure (SBP) ≥ 110 mmHg (2.66; 1.12-6.28). In patients with HFrEF, the proportion of HF medications not initiated simultaneously with SV was significantly higher in the continuation group than in the discontinuation group (67.3% vs 33.3%, P = 0.002). The number of HF medications and their combination patterns were not significantly associated with SV continuation. Albumin, BMI, and SBP are useful indicators for selecting patients who are likely to continue SV. In addition, initiating only SV without simultaneously initiating other HF medications in patients with HFrEF may lead to SV continuation.

Endogenous bufadienolides, mineralocorticoid receptor antagonists and fibrosis in chronic kidney disease.

Every year millions die prematurely of complications related to chronic kidney disease (CKD). Main causes of death are connected with cardiovascular (CV) complications. There is no cure for CKD although current treatment can slow the progression of the disease if diagnosed early. Fortunately, last decades have witnessed an accelerating pace of discovery regarding the cellular and molecular basis for CKD and CV disease. Novel biomarkers, including amino-terminal type III procollagen peptide (PIIINP), carboxy-terminal type I procollagen peptide (PICP), FGF23, marinobufagenin, and several miRNAs, show promise for early detection and risk stratification. In this review, we provide an overview of recent advances in the "fibrotic concept" of the etiology and pathogenesis of CKD which involves system consisting of Na/K-ATPase and its endogenous ligands including marinobufagenin which inhibits Fli1 and stimulates synthesis of collagen-1 in the vasculature. A novel treatment of CKD already involves the use of mineralocorticoid receptor antagonists capable of impairing marinobufagenin-Na/K-ATPase interactions.

Finerenone and left ventricular hypertrophy in chronic kidney disease and type 2 diabetes.

Left ventricular hypertrophy (LVH) has been associated with an increased risk of cardiovascular (CV) disease and linked to increased morbidity and mortality. In patients with chronic kidney disease (CKD) and type 2 diabetes (T2D), hypertension is common, and patients with these co-morbidities additionally have a high prevalence of LVH. This analysis of the prespecified pooled FIDELITY analysis comprising the randomized, double-blind, placebo-controlled, multicentre FIDELIO-DKD and FIGARO-DKD phase III studies aimed to explore the CV and kidney effects of finerenone, a nonsteroidal mineralocorticoid receptor antagonist, in patients with CKD and T2D stratified by a diagnosis of LVH at baseline. A diagnosis of LVH in the FIDELITY patient population was determined at baseline using investigator-reported electrocardiogram (ECG) findings. The two efficacy outcomes, assessed by baseline LVH, were the composite CV outcome of time to CV death, non-fatal myocardial infarction, non-fatal stroke, or hospitalization for heart failure (HHF), and a composite kidney outcome of time to onset of kidney failure, a sustained decrease in estimated glomerular filtration rate (eGFR)≥57% from baseline over ≥4weeks, or kidney-related death. Safety outcomes by baseline LVH were reported as treatment-emergent adverse events. At baseline out of 13026 patients in FIDELITY, 96.5% had hypertension and 9.6% had investigator-reported LVH. The relative risk reduction for the composite CV and kidney outcomes with finerenone versus placebo was lower in the LVH subgroup; however, the treatment effect of finerenone was not modified by baseline LVH for either outcome (Pinteraction=0.1075 for composite CV outcome and Pinteraction=0.1782 for composite kidney outcome). Analysis of the composite CV outcome components showed a greater reduction in the risk of HHF versus placebo for patients with baseline LVH compared with those without (Pinteraction=0.0024). Overall safety events were comparable between the LVH subgroups and treatment arms. Treatment-emergent hyperkalaemia was observed more frequently with finerenone versus placebo, but discontinuation rates were low in both treatment arms and between LVH subgroups. In conclusion, the overall CV and kidney benefits of finerenone versus placebo were not modified by the presence of LVH at baseline, with overall safety findings being similar between LVH subgroups. A greater benefit was observed for HHF in patients with versus without LVH, suggesting that LVH may be a predictor of the treatment effect of finerenone on HHF.

Epidemiology of paediatric chronic heart failure in Germany-A population-based analysis.

Paediatric chronic heart failure (CHF) is associated with significant morbidity. The aim of this study was to describe paediatric CHF epidemiology in Germany. This is a retrospective cross-sectional analysis of anonymized healthcare claims data in the InGef database. This database includes longitudinal data from a representative sample of the German population of approximately 4.8 million insured members. We included individuals <18years from 2016 to 2021. CHF was defined by ≥2 diagnoses in different quarters of the year as inpatient or outpatient, using ICD-10-GM codes I50.- or P29.0. The number of eligible children in the database was 674462 in 2016 and 660692 in 2021. Prevalence of CHF per 100000 children was 20.6 [95% confidence interval (CI), 17.3-24.3] in 2016 and 19.4 (95% CI, 16.2 to 23.0) in 2021. Incidence per 100000 children was 9.6 (95% CI, 7.4 to 12.3) in 2016 and 7.6 (95% CI, 5.6 to 10.0) in 2021 for newly diagnosed CHF. All-cause hospitalizations occurred in 47.3% to 57.7% of children with CHF per year. Up to 6.3% of children with CHF were hospitalized, coded primarily for heart failure. Mortality of children with CHF was <5 death per year in the studied population. In 128 children with CHF in 2021, the most common ICD-coded comorbidities were congenital malformations of cardiac septa (57.8%), atrial septal defect (44.5%), congenital malformations of the great arteries (43.0%) and ventricular septal defect (32.0%). Coded treatment modalities for paediatric CHF in 2021 included angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor blockers (18.8%), beta-blockers (17.2%), mineralocorticoid receptor antagonists (14.8%) and surgical procedures (13.3%). This representative cohort study reveals a relatively high incidence proportion. Approximately half of the children with CHF are hospitalized annually while mortality is low.

The mineralocorticoid receptor in diabetic kidney disease.

Diabetes mellitus is one of the leading causes of chronic kidney disease and its progression to end-stage kidney disease (ESKD). Diabetic kidney disease (DKD) is characterized by glomerular hypertrophy, hyperfiltration, inflammation, and the onset of albuminuria, together with a progressive reduction in glomerular filtration rate. This progression is further accompanied by tubulointerstitial inflammation and fibrosis. Factors such as genetic predisposition, epigenetic modifications, metabolic derangements, hemodynamic alterations, inflammation, and inappropriate renin-angiotensin-aldosterone system (RAAS) activity contribute to the onset and progression of DKD. In this context, decades of work have focused on glycemic and blood pressure reduction strategies, especially targeting the RAAS to slow disease progression. Although much of the work has focused on targeting angiotensin II, emerging data support that the mineralocorticoid receptor (MR) is integral in the development and progression of DKD. Molecular mechanisms linked to the underlying pathophysiological changes derived from MR activation include vascular endothelial and epithelial cell responses to oxidative stress and inflammation. These responses lead to alterations in the microcirculatory environment, the abnormal release of extracellular vesicles, gut dysbiosis, epithelial-mesenchymal transition, and kidney fibrosis. Herein, we present recent experimental and clinical evidence on the MR in DKD onset and progress along with new MR-based strategies for the treatment and prevention of DKD.

Abstract 60: Atlas of Distal Nephron Mineralocorticoid Receptor-Dependent Transcriptome Reveals Novel Aldosterone Actions

Aldosterone regulation of Na+ and K+ balance and blood pressure are mediated by the mineralocorticoid receptor (MR, Nr3c2). Although several aldosterone/MR-dependent genes have been identified, their regulation cannot fully explain how aldosterone activates electrogenic Na+- K+ exchange in the aldosterone-sensitive distal nephron (ASDN). Here, we apply RNA-Seq and comprehensive downstream analysis to define the complete inventory of MR-regulated genes. MRfl/fl/Pax8,rtTA/LC1 mice were used to knock out the Nr3c2 gene in an inducible and kidney-specific manner. RNA-Seq analysis was conducted in the micro-dissected connecting tubule and cortical collecting duct tubule segments, followed by multimodal bioinformatic analyses. Direct MR-dependent gene regulation was validated in vitro on immortalized collecting duct cells, ex vivo with isolated distal nephron segments and gene reporter assays. All known aldosterone-response genes, including Sgk1, Scnn1a, Ndrg2, Per3, Tsc22d3, Zbtb16, MLPH, and Atp1a1 were significantly decreased in MR KO mice. 1193 additional genes were down-regulated in the MR KO, and 526 of these have a Mineralocorticoid Responsive Element (MRE), revealing the MR-dependent transcriptome is much larger than previously imagined. MREs were found in most genes with closed chromatin regions, suggesting MR binding might pioneer transcription for most of its regulated genes. The architecture of some MR-regulated genes, highlighted by the co-regulation of 7 Kallikrein genes, points to a novel mechanism of MR-regulation involving epigenetic remodeling in topology-associated domains. Pathway enrichment analysis revealed that MR-regulated genes are highly enriched in mitochondria-associated metabolic processes, and direct MR regulation of Klf15 was identified as a key transcriptional driver. In summary, the inventory of MR-regulated genes in the ASDN is much larger than previously imagined, involving new mechanisms of gene regulation. In addition to pathways that directly up-regulate transport, the data suggest that aldosterone-MR may directly influence metabolism to make energy-consuming transport highly efficient.

Abstract P443: Role of miRNA-99a, endothelial mineralocorticoid receptor and CD36 in arterial stiffening

The surge in overweight and obesity rates has triggered a rise in metabolic syndrome cases and related cardiovascular diseases, including vascular stiffness and hypertension. We recently found that consumption of a high-fat/high-fructose Western diet (WD) increases the expression and activation of endothelial cell (EC) mineralocorticoid receptor (ECMR), which is associated with arterial oxidative stress, inflammation, remodeling, and vascular stiffening. However, the precise mechanisms by which enhanced activation of ECMR induces vascular stiffening remain to be elucidated. We hypothesize that miR-99a regulates the activated ECMR-induced upregulation of ECCD36 expression, which promotes vascular endothelial dysfunction and aortic stiffness. First, 16 weeks of WD inhibited miR-99a in the aorta which was prevented by additional spironolactone treatment. With bioinformatics, we predicted that miR-99a would target CD36 expression. To test our hypothesis that miR-99a, regulated by ECMR activation, may also directly affect CD36 mRNA expression in cultured ECs, we used miR-99a mimic or inhibitor to transfect ECs with or without palmitic acid treatment. miR-99a mimic also prevented palmitic acid-induced EC CD36 expression and lipid droplet formation. In vivo gene deletion of ECCD36 blunted WD-induced increases in pulse pressure and reduced vascular activity as well as aortic remodeling. These data indicate that the interaction of endothelial-specific ECMR/miRNA/ECCD36 mediates vascular endothelium dysfunction and prompts arterial stiffness.

Abstract 10: Adrenal Zona Glomerulosa Long Form Leptin Receptor (LepRb) Protects from Leptin-Mediated Vascular Disorders in Female Mice

Introduction: Previous work from our group demonstrated that leptin is a major contributor to obesity-associated cardiovascular disease, in females, by acting on the adrenal gland to promote aldosterone production. Hypothesis: This leptin-mediated aldosterone secretion is dependent on the presence of the long form leptin receptor (LepRb) in adrenal aldosterone synthase (AS) expressing cells. Methods: We generated AS LepRb deficient mice, ASKO and WT control (ASWT), by crossing LepRb flox/flox mice with AS-Cre mice to investigate the role of LepRb in AS expressing cells in leptin-mediated cardiovascular alteration in females and also generated db/AS + mice that have LepRb only in AS expressing cells by crossing LepR TBflox/flox (db/db) with AS-Cre mice to compare their phenotype. Results: Under baseline conditions, ASKO female mice exhibited no alteration in adrenal AS, plasma aldosterone, systolic blood pressure, and aortic endothelium-dependent relaxation. To mimic obese conditions, we submitted ASWT and ASKO to chronic leptin infusion for a week. Leptin increased adrenal AS expression, aldosterone levels, and blood pressure and impaired endothelial function, which were further elevated in ASKO compared to ASWT, suggesting protective effects of AS LeRb. Both mineralocorticoid receptor (MR) antagonist. eplerenone, or AS antagonist, fadrazole, rescued endothelial function in ASWT and ASKO mice treated with leptin, indicating that leptin-mediated endothelial dysfunction is still aldosterone-dependent in ASKO mice. Restoration of LepRb in AS expressing cells in db/db decreased adrenal AS and plasma aldosterone and improved endothelial function further indicating that AS LepRb blunts leptin-mediated aldosterone production. On a molecular level, leptin treatment elevated aorta NOX1 expression in ASWT, which was further increased in ASKO. Aldosterone treatment increased NOX1 expression in cultured microvascular endothelial cells. Incubation of aortic rings with a selective NOX1 inhibitor restored endothelial function in both ASWT and ASKO treated with leptin, suggesting leptin-mediated aldosterone increased NOX1 expression in the aorta, which causes endothelial dysfunction. Conclusion: These data indicate that AS LepRb protects from leptin-mediated aldosterone production and vascular dysfunction by mitigating the effects of leptin on aldosterone production and suggests that other isoforms of LepR are involved in stimulating aldosterone production.

The mineralocorticoid system, cardiometabolic health and its interplay with adipose tissue.

The mineralocorticoid system, comprising the renin-angiotensin-aldosterone system (RAAS) and associated receptors, is traditionally viewed as a regulator of sodium and fluid balance and blood pressure (BP), with the main mineralocorticoid hormone aldosterone acting via the mineralocorticoid receptor (MR) in distal renal tubules. Over the past few decades, there has been a wider understanding of the role of the mineralocorticoid system in regulating both classical BP-dependent and non-BP-dependent systemic effects. Mounting evidence indicates the novel role of the mineralocorticoid system in cardiometabolic health with excess mineralocorticoid system activity being associated with adiposity, diabetes, insulin resistance and cardiovascular diseases independent of its effect on BP, and RAAS blockade and MR antagonists offering protection against cardiometabolic dysfunction. The metabolic manifestations of mineralocorticoid system overactivation are mainly mediated by their interactions with adipose tissue which orchestrates energy, lipids and glucose homeostasis via effects on the functions of brown and white adipocytes and immune cells. Adipose tissue can in turn influence mineralocorticoid system activity by harbouring its own RAAS system and by releasing mineralocorticoid-secretory factors/adipokines, with resultant further progression of cardiometabolic dysfunction. This article discusses the interplay between the mineralocorticoid system and adipose tissue in the pathophysiology of cardiometabolic diseases.

Role of L-type Ca2+-channels in the vasorelaxing response to finerenone in arteries of human visceral adipose tissue.

Inadequate blood supply to the expanding adipose tissue (AT) is involved in the unhealthy AT remodeling and cardiometabolic consequences of obesity. Because of the pathophysiological role of upregulated mineralocorticoid receptor (MR) signaling in the complications of obesity, this study tested the vasoactive properties of finerenone, a nonsteroidal MR antagonist, in arteries of human AT. Arteries isolated from the visceral AT of obese subjects were studied in a wire myograph. Finerenone resulted in a concentration-dependent relaxation of arteries precontracted with either the thromboxane-A2 analog U46619, ET-1, or high-K+ solution; the steroidal MR antagonist potassium canrenoate, by contrast, did not relax arteries contracted with either U46619 or high-K+ solution. Finerenone-induced relaxation after precontraction with U46619 was greater in the arteries of obese versus nonobese subjects. Mechanistically, the vasorelaxing response to finerenone was not influenced by preincubation with the nitric oxide synthase inhibitor L-NAME or by endothelium removal. Interestingly, finerenone, like the dihydropyridine Ca2+-channel blocker nifedipine, relaxed arteries contracted with the L-type Ca2+-channel agonist Bay K8644. In conclusion, finerenone relaxes arteries of human visceral AT, likely through antagonism of L-type Ca2+ channels. This finding identifies a novel mechanism by which finerenone may improve AT perfusion, hence protecting against the cardiometabolic complications of obesity.

Therapeutic Effects of Heart Failure Medical Therapies on Standardized Kidney Outcomes: Comprehensive Individual Participant-Level Analysis of 6 Randomized Clinical Trials.

Background: Kidney outcomes have been variably defined using non-standardized composite endpoints in key heart failure (HF) trials, thus introducing complexity in their interpretation and cross-trial comparability. We examined the effects of steroidal mineralocorticoid receptor antagonists (MRAs), the angiotensin receptor-neprilysin inhibitor (ARNI) sacubitril/valsartan, and sodium-glucose cotransporter-2 (SGLT2) inhibitors on composite kidney endpoints using uniform definitions in 6 contemporary HF trials. Methods: Individual participant-level data from trials of steroidal MRAs (EMPHASIS-HF, TOPCAT Americas), ARNI (PARADIGM-HF, PARAGON-HF), and SGLT2 inhibitors (DAPA-HF, DELIVER) were included. The standardized composite kidney endpoint was defined as a sustained decline (a reduction in estimated glomerular filtration rate (eGFR) confirmed by a subsequent measurement at least 30 days later) in eGFR by 40%, 50%, or 57%, end-stage kidney disease, or renal death. eGFR was recalculated in a standardized manner using the 2009 Chronic Kidney Disease Epidemiology Collaboration creatinine equation. Results: Among 28,690 participants across the 6 trials (median age 69 years [IQR, 62-76]; 9,656 [33.7% ] women), the proportion experiencing the composite kidney endpoint with a more stringent definition of a sustained decline in kidney function (eGFR threshold of 57%) ranged from 0.3% to 3.3%. The proportion of patients experiencing this endpoint with a less stringent definition (eGFR threshold of 40%) ranged from 1.0% and 10.0%. The steroidal MRAs doubled the risk of the composite kidney endpoint when applying the least stringent definition compared with placebo, but these effects were less apparent and no longer significant with application of more stringent definitions. ARNI appeared to consistently reduce the occurrence of the composite kidney endpoints irrespective of specific eGFR threshold applied. The potential benefits of SGLT2-inhibitors on the composite kidney endpoints appeared more apparent when defined by more stringent eGFR thresholds, although none of these effects individually were statistically significant. Conclusions: When applying standardized stringent kidney endpoint definitions, steroidal MRAs, ARNI, and SGLT2-inhibitors have either neutral or beneficial effects on kidney outcomes in HF. Applying less stringent definitions increased event rates but included acute declines in eGFR that might not ultimately reflect long-term effects on kidney disease progression.

Finerenone in heart failure and chronic kidney disease with type 2 diabetes: FINE-HEART pooled analysis of cardiovascular, kidney and mortality outcomes.

Cardiovascular-kidney-metabolic syndrome is an emerging entity that connects cardiovascular diseases, chronic kidney disease and diabetes. The non-steroidal mineralocorticoid receptor antagonist finerenone has been studied in three prospective randomized clinical trials of patients with cardiovascular-kidney-metabolic syndrome: FIDELIO-DKD, FIGARO-DKD and FINEARTS-HF. In light of the strong epidemiological overlap and shared mechanistic drivers of clinical outcomes across cardiovascular-kidney-metabolic syndrome, we summarize the efficacy and safety of finerenone on cardiovascular, kidney and mortality outcomes in this pre-specified participant-level pooled analysis. The three trials included 18,991 participants (mean age 67 ± 10 years; 35% women). During 2.9 years of median follow-up, the primary outcome of cardiovascular death occurred in 421 (4.4%) participants assigned to finerenone and 471 (5.0%) participants assigned to placebo (hazard ratio (HR): 0.89; 95% confidence interval (CI): 0.78-1.01; P = 0.076). Death from any cause occurred in 1,042 (11.0%) participants in the finerenone arm and in 1,136 (12.0%) participants in the placebo arm (HR: 0.91; 95% CI: 0.84-0.99; P = 0.027). Finerenone further reduced the risk of hospitalization from heart failure (HR: 0.83; 95% CI: 0.75-0.92; P < 0.001) and the composite kidney outcome (HR: 0.80; 95% CI: 0.72-0.90; P < 0.001). While in this pooled analysis the reduction in cardiovascular death was not statistically significant, finerenone reduced the risks for deaths of any cause, cardiovascular events and kidney outcomes. PROSPERO identifier: CRD42024570467 .