Mineralocorticoid Receptor Blocker Research Articles

Home blood pressure control and prescribing patterns of anti-hypertensive medications in a home blood pressure-based hypertension-specialized clinic in Japan: a sub-analysis of the Ohasama study.

Although the benefits of anti-hypertensive treatment are well known, the proportion of hypertensive patients with controlled blood pressure (BP) remains suboptimal. The present study aimed to compare BP control conditions in a hypertension-specialized clinic and non-hypertension-specialized clinics. This cross-sectional study used data from 379 treated patients who measured home BP in the Ohasama study between 2016 and 2019 (men: 43.0%, age: 71.6 years). Of those, 172 patients were managed at the hypertension-specialized clinic where physicians distributed home BP devices to each patient, evaluated the home BP data, and adjusted medications to maintain home BP values according to the recent Japanese guidelines. When we set morning home systolic/diastolic BP of <135/ < 85 mmHg as controlled BP, 93.6% of patients fulfilled the controlled home BP range, compared to 43.0% in non-specialized clinics (n = 207). The proportion of the patients with home morning BP < 125/ < 75 mmHg was 73.3% in the hypertension-specialized clinic and 20.8% in the non-hypertension-specialized clinics. Hypertension-specialized clinics prescribed three or more anti-hypertensive drug classes to 41.9% of patients, compared to 15.2% in non-specialized clinics. In the hypertension-specialized clinic, angiotensin II receptor blockers were most commonly prescribed (86.6%), followed by dihydropyridine calcium channel blockers (77.9%), thiazide (including thiazide-like) diuretics (30.2%), mineralocorticoid receptor blockers (23.8%), and beta- and alpha-beta blockers (10.5%). In conclusion, the proportion of patients with controlled home BP was excellent in the hypertension-specialized clinic. Home BP-based hypertension practices, as recommended in the current Japanese guidelines, may be the key to achieving sufficient BP control.

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.

Esaxerenone Attenuates Aldosterone-Induced Mitochondrial Damage-Mediated Pyroptosis in Mouse Aorta and Rat Vascular Smooth Muscle Cells.

Vascular smooth muscle cell (VSMC) injury caused by the inflammatory response plays a key role in cardiovascular disease (CVD), and the vasoprotective effects of mineralocorticoid receptor blockers (MRBs) support the role of mineralocorticoid receptor (MR) activation. C57BL/6 mice and VSMCs isolated from rats were treated with aldosterone and esaxerenone. Caspase-1, GSDMD-N, IL-1β, and NR3C2 expression and DNA damage in aortic VSMCs were detected using immunohistochemistry, Western blotting, and TUNEL staining. Mitochondrial changes were detected by transmission electron microscopy (TEM). Reactive oxygen species (ROS), MitoTracker, JC-I, mitochondrial respiratory chain complexes I-V, and NR3C2 were detected using immunofluorescence and flow cytometry. Pyroptosis was detected with scanning electron microscopy (SEM). After aldosterone treatment, the number of TUNEL-positive cells increased significantly, and the expression of caspase-1, GSDMD-N, and IL-1β increased. TEM revealed mitochondrial damage, and SEM revealed specific pyroptotic changes, such as cell membrane pore changes and cytoplasmic extravasation. Increased ROS levels and nuclear translocation of NR3C2 were also observed. These pyroptosis-related changes were reversed by esaxerenone. Aldosterone activates the MR and mediates mitochondrial damage, thereby inducing pyroptosis in VSMCs via the NLRP3/caspase-1 pathway. Esaxerenone inhibits MR activation and reduces mitochondrial damage and oxidative stress, thereby inhibiting pyroptosis.

Esaxerenone: blood pressure reduction and cardiorenal protection without reflex sympathetic activation in salt-loaded stroke-prone spontaneously hypertensive rats.

Mineralocorticoid receptor (MR) is involved in the mechanisms of blood pressure elevation, organ fibrosis, and inflammation. MR antagonists have been used in patients with hypertension, heart failure, or chronic kidney disease. Esaxerenone, a recently approved MR blocker with a nonsteroidal structure, has demonstrated a strong blood pressure-lowering effect. However, blood pressure reduction may lead to sympathetic activation through the baroreflex. The effect of esaxerenone on the sympathetic nervous system remains unclear. We investigated the effect of esaxerenone on organ damage and the sympathetic nervous system in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP), a well-established model of essential hypertension with sympathoexcitation and organ damage. Three-week administration of esaxerenone or hydralazine successfully attenuated the blood pressure elevation. Both esaxerenone and hydralazine comparably suppressed left ventricular hypertrophy and urinary albumin excretion. However, renal fibrosis and glomerular sclerosis were suppressed by esaxerenone but not hydralazine. Furthermore, plasma norepinephrine level, a parameter of systemic sympathetic activity, was significantly increased by hydralazine but not by esaxerenone. Consistent with these findings, the activity of the control centers of sympathetic nervous system, the parvocellular region of the paraventricular nucleus in the hypothalamus and the rostral ventrolateral medulla, was enhanced by hydralazine but remained unaffected by esaxerenone. These results suggest that esaxerenone effectively lowers blood pressure without inducing reflex sympathetic nervous system activation. Moreover, the organ-protective effects of esaxerenone appear to be partially independent of its blood pressure-lowering effect. In conclusion, esaxerenone demonstrates a blood pressure-lowering effect without concurrent sympathetic activation and exerts organ-protective effects in salt-loaded SHRSP. Esaxerenone has antihypertensive and cardiorenal protective effects without reflex sympathetic activation in salt-loaded stroke-prone spontaneously hypertensive rats.

#87 Hospital readmissions among individuals with severe kidney disease hospitalized for fluid overload

Abstract Background and Aims Fluid overload is a common presentation and a leading cause for hospitalizations in severe kidney disease, but interventions can help reduce readmissions. To identify at-risk individuals, we evaluated the incidence and risk factors associated with fluid overload and all-cause hospital readmission among individuals with severe kidney disease. Method Single-center retrospective cohort study of patients hospitalized in Singapore General Hospital for fluid overload between 2015 and 2017. Fluid overload was identified from discharge codes for fluid overload, heart failure, pulmonary edema, and generalized edema. Patients were included if their estimated glomerular filtration rate (eGFR) was between 11 and 30 ml/min/1.73 m2, but excluded if they had urgent indications for dialysis or were lost to follow-up (Fig. 1). Baseline data on demographics, comorbidities, biochemistry and medication use during admission were retrieved from electronic medical records up till 30th December 2018. The outcomes were fluid overload-related and all-cause readmissions within 30 days of discharge of the index hospitalization. Multivariable logistic regression analysis (stepwise method) was performed with inclusion of covariates with P ≤ .10 on univariate analysis. Results Among 783 patients, the median age was 75 (IQR 67, 83) years and the admission eGFR was 20.9 (IQR 16.1, 25.4) ml/min/1.73 m2 at index hospitalization. 30-day readmission for fluid overload and all-causes occurred in 10.6% and 26.8% of the cohort, respectively (Table 1). Individuals with fluid overload readmissions were more likely to have atherosclerotic cardiovascular disease (ASCVD), atrial fibrillation (AF), prior hospitalization for fluid overload within 6 months, lower serum sodium and bicarbonate, but higher serum potassium at admission (Table 1). They were less likely to have hypertension, prior nephrology consult within 3 months and renin-angiotensin system (RAS) blocker prescription at discharge. In multivariable analysis, 30-day readmission for fluid overload was independently associated with ASCVD (adjusted odds ratio (aOR) 1.81, 95% CI 1.08-3.03, P = .02), AF (aOR 1.93, 95% CI 1.13-3.29, p = 0.02), higher serum potassium (aOR 1.61, 95% CI 1.14-2.26, P = .007), high-dose intravenous furosemide (aOR 1.66, 95% CI 1.02-2.67, P = .04), and inversely associated with prior nephrology consult (aOR, 0.51, 95% CI 0.29-0.89, P = .02) and RAS blocker prescription at discharge (aOR 0.61, 95% CI 0.38-0.99, P = .04). Individuals with all-cause readmissions were more likely to have AF, more frequent emergency department visits within 6 months, lower eGFR and serum sodium, but higher serum potassium on admission, longer length of stay and higher LACE index (Table 1). They were less likely to have hypertension, RAS blocker and statin prescription at discharge. 30-day readmission for all-causes was independently associated with higher number of emergency department visits (aOR 1.21, 95% CI 1.04-1.40, P = .02), higher LACE index (aOR 1.08, 95% CI 0.001-1.17, P = .048), and inversely associated with mineralocorticoid receptor blocker (aOR 0.55, 95% CI 0.31-0.97, P = .04) and statin prescription at discharge (aOR 0.51, 95% CI 0.33-0.78, P = .002) in multivariable analysis. Conclusion Risk stratification of patients with severe kidney disease who are at-risk of fluid overload and all-cause readmissions may allow for targeted interventions to reduce hospital readmissions.

Nonsteroidal mineralocorticoid receptor blockers as a new tool for managing cardiorenal risks in type 2 diabetes mellitus

Today, the importance of targeted cardionephroprotection is increasingly increasing as one of the vectors of a multifactorial therapeutic strategy to reduce the risk of development and progression of complications of type 2 diabetes. Pathological hyperactivation of the renin-angiotensin-aldosterone system (RAAS) and mineralocorticoid receptors (MCRs) is considered as one of the mechanisms for the development of cadiorenal syndrome (RCS) in diabetes. Blocking this pathophysiological pathway in patients with CKD and type 2 diabetes can break the vicious circle of mutually aggravating damage to the kidneys and heart. ACE inhibitors and angiotensin receptor blockers (ARBs) are currently the standard of care in patients with CRS due to diabetes. But despite their effectiveness, the residual risk of CKD progression within 4–5 years remains high in almost half of patients with type 2 diabetes, mainly due to multicomponent processes of MCR hyperactivation. This causes a range of pathological reactions affecting the entire body and may contribute to kidney, heart and CD disease in patients with type 2 diabetes by promoting inflammation and fibrosis. Functional and structural changes in the kidneys and heart develop, which leads to the development of metabolic disorders, arterial hypertension, cardiovascular complications and progressive CKD. Pharmacological blockade of aldosterone binding to MCR appears to be an effective additional line for preventing the progression of the pathological cascade of KRS reactions in type 2 diabetes. The recently developed selective non-steroidal MCR antagonist (nsAMPR) finerenone has convincingly demonstrated improved renal and cardiovascular outcomes in patients with CKD and type 2 diabetes. This review covers in detail the role of MCRs in the development of cardiorenal syndrome in type 2 diabetes and CKD, describes the mechanisms of effectiveness of MCR blockade in preventing the progression of cardiorenal syndrome in type 2 diabetes and the difference between non-steroidal MCRs and steroids, and presents the results of RCTs confirming the cardionephroprotective potential of nsAMCRs in CKD and diabetes. type 2, and the place of finerenone as a multifactorial therapeutic strategy for type 2 diabetes in clinical practice.

Esaxerenone Inhibits Interferon-γ Induced Pyroptosis of Macrophages in the Lungs of Aldosterone-treated Mice.

Lung immune cells such as lymphocytes and macrophages can induce an inflammatory response due to the activation of mineralocorticoid receptor (MR), which is manifested by the infiltration of inflammatory cells and the secretion of inflammatory cytokines and subsequent apoptosis, pyroptosis and necrosis of intrinsic lung cells and immune cells. Macrophages are immune cells that are abundant in the lung and act as the first line of defense against pathogens but are also aggravating factors of infection. The activation of the renin-angiotensin-aldosterone system (RAAS), especially aldosterone-stimulated MR activation, can induce macrophage and CD8+T cell aggregation and the secretion of cytokines such as tumor necrosis factor-α (TNF-α) and interferon-gamma (IFN-γ). Increased IFN-γ secretion can induce macrophage pyroptosis and the release of interleukin 1-β (IL-1β), aggravating lung injury. In this study, lung injury in C57BL/6 mice was induced by subcutaneous micro-osmotic pump infusion of aldosterone. After 12weeks of administration, the kidney, heart, blood vessels and lungs all showed obvious inflammatory injury, which manifested as rapid accumulation of macrophages. The overexpression of IFN-γ in the lungs of aldosterone-treated mice and the stimulation of MH-S and RAW264.7 alveolar macrophages (AMs) with aldosterone in vitro showed that IFN-γ induced pyroptosis of macrophages via the activation of the inflammasome, and the MR blocker esaxerenone effectively inhibited this effect and alleviated lung injury. In addition, IFN-γ secreted by CD8+T cells is associated with macrophage pyroptosis. In conclusion, the inhibition of macrophage pyroptosis can effectively alleviate lung injury.

Eplerenone reduces lymphangiogenesis in the contralateral kidneys of UUO rats.

Inflammation and fibrosis often occur in the kidney after acute injury, resulting in chronic kidney disease and consequent renal failure. Recent studies have indicated that lymphangiogenesis can drive renal inflammation and fibrosis in injured kidneys. However, whether and how this pathogenesis affects the contralateral kidney remain largely unknown. In our study, we uncovered a mechanism by which the contralateral kidney responded to injury. We found that the activation of mineralocorticoid receptors and the increase in vascular endothelial growth factor C in the contralateral kidney after unilateral ureteral obstruction could promote lymphangiogenesis. Furthermore, mineralocorticoid receptor activation in lymphatic endothelial cells resulted in the secretion of myofibroblast markers, thereby contributing to renal fibrosis. We observed that this process could be attenuated by administering the mineralocorticoid receptor blocker eplerenone, which, prevented the development of fibrotic injury in the contralateral kidneys of rats with unilateral ureteral obstruction. These findings offer valuable insights into the intricate mechanisms underlying kidney injury and may have implications for the development of therapeutic strategies to mitigate renal fibrosis in the context of kidney disease.

The potential for improved outcomes in the prevention and therapy of diabetic kidney disease through 'stacking' of drugs from different classes.

Aggressive therapy of diabetic kidney disease (DKD) can not only slow the progression of DKD to renal failure but, if utilized at an early enough stage of DKD, can also stabilize and/or reverse the decline in renal function. The currently recognized standard of therapy for DKD is blockade of the renin-angiotensin system with angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs). However, unless utilized at a very early stage, monotherapy with these drugs in DKD will only prevent or slow the progression of DKD and will neither stabilize nor reverse the progression of DKD to renal decompensation. Recently, the addition of a sodium-glucose cotransporter-2 inhibitor and/or a mineralocorticoid receptor blocker to ACE inhibitors or ARBs has been clearly shown to further decelerate the decline in renal function. The use of glucagon-like peptide-1 (GLP-1) agonists shown promise in decelerating the progression of DKD. Other drugs that may aid in the deceleration the progression of DKD are dipeptidyl peptidase-4 inhibitors, pentoxifylline, statins, and vasodilating beta blockers. Therefore, aggressive therapy with combinations of these drugs (stacking) should improve the preservation of renal function in DKD.

Effects of the mineralocorticoid receptor antagonist eplerenone in experimental autoimmune encephalomyelitis

There is growing evidence indicating that mineralocorticoid receptor (MR) expression influences a wide variety of functions in metabolic and immune response. The present study explored if antagonism of the MR reduces neuroinflammation in the spinal cord of mice with experimental autoimmune encephalomyelitis (EAE). Eplerenone (EPLE) (100 mg/kg dissolved in 30% 2-hydroxypropyl-β-cyclodextrin) was administered intraperitoneally (i.p.) daily from EAE induction (day 0) until sacrificed on day 17 post-induction. The MR blocker (a) significantly decreased the inflammatory parameters TLR4, MYD88, IL-1β, and iNOS mRNAs; (b) attenuated HMGB1, NLRP3, TGF-β mRNAs, microglia, and aquaporin4 immunoreaction without modifying GFAP. Serum IL-1β was also decreased in the EAE+EPLE group. Moreover, EPLE treatment prevented demyelination and improved clinical signs of EAE mice. Interestingly, MR was decreased and GR remained unchanged in EAE mice while EPLE treatment restored MR expression, suggesting that a dysbalanced MR/GR was associated with the development of neuroinflammation. Our results indicated that MR blockage with EPLE attenuated inflammation-related spinal cord pathology in the EAE mouse model of Multiple Sclerosis, supporting a novel therapeutic approach for immune-related diseases.

Exploratory study on the relationship between urinary sodium/potassium ratio, salt intake, and the antihypertensive effect of esaxerenone: the ENaK Study

Excessive salt intake is one of the causes of hypertension, and reducing salt intake is important for managing the risk of hypertension and subsequent cardiovascular events. Esaxerenone, a mineralocorticoid receptor blocker, has the potential to exert an antihypertensive effect in hypertensive patients with excessive salt intake, but evidence is still lacking, especially in clinical settings. We aimed to determine if baseline sodium/potassium ratio and baseline estimated 24-h urinary sodium excretion can predict the antihypertensive effect of esaxerenone in patients with essential hypertension inadequately controlled with an angiotensin receptor blocker (ARB) or a calcium channel blocker (CCB). This was an exploratory, open-label, interventional study with a 4-week observation period and a 12-week treatment period. Esaxerenone was orally administered once daily in accordance with the Japanese package insert. In total, 126 patients met the eligibility criteria and were enrolled (ARB subcohort, 67; CCB subcohort, 59); all were included in the full analysis set (FAS) and safety analysis. In the FAS, morning home systolic blood pressure (SBP)/diastolic blood pressure (DBP) significantly decreased from baseline to end of treatment (primary efficacy endpoint) (−11.9 ± 10.9/ − 6.4 ± 6.8 mmHg, both p < 0.001); a similar trend was observed in both subcohorts. Significant reductions were also shown in bedtime home and office SBP/DBP (all p < 0.001). Each BP change was consistent regardless of the urinary sodium/potassium ratio or estimated 24-h urinary sodium excretion at baseline. The urinary albumin-creatinine ratio (UACR) and N-terminal pro-brain natriuretic peptide (NT-proBNP) significantly decreased from baseline to Week 12 in the total population and both subcohorts. No new safety concerns were raised. Esaxerenone significantly decreased morning home, bedtime home, and office BP; UACR; and NT-proBNP in this patient population, regardless of concomitant ARB or CCB use. The antihypertensive effect of esaxerenone was independent of the urinary sodium/potassium ratio and estimated 24-h urinary sodium excretion at baseline.

Additive Effects of Esaxerenone, a Nonsteroidal Mineralocorticoid Receptor Blocker, on Cardioplegic Arrest in Rat Hearts.

Esaxerenone, a mineralocorticoid receptor blocker, attenuates global ischemia-induced myocardial damage and coronary endothelial dysfunction. This study aimed to determine whether esaxerenone exerted cardioprotective effects against cardioplegic arrest in Wistar rat hearts. Isolated male Wistar rat hearts aerobically perfused via the Langendorff method for 20 min were randomly allocated to the Control (n = 6; perfused for an additional 10 min and subjected to no treatment) or Esax (n = 6; perfused with 0.1 μmol/L esaxerenone in perfusate for 10 min before ischemia) groups. Hearts in both groups were perfused with St. Thomas' Hospital No. 2 solution (STH2) for 2 min and subjected to 28 min of global ischemia. The recovery of left ventricular developed pressure (LVDP) and total troponin T leakage were measured after reperfusion. The final recovery of LVDP (expressed as a percentage of pre-ischemic value) in the Control and Esax groups was 50.8 ± 3.5% and 62.1 ± 5.6%, respectively (p <0.05, Esax vs. Control). The total troponin T leakage in the Control and Esax groups was 138.8 ± 18.5 ng/g heart wt and 74.3 ± 18.6 ng/g heart wt, respectively (p <0.05, Esax vs. Control). The administration of esaxerenone before cardioplegic arrest enhanced the cardioprotective effect exerted by STH2.

Bilateral or Unilateral Aldosterone Hypersecretion and Responsiveness to Therapy Are Associated with Differences in Calcium/Phosphate Homeostasis in Patients with Primary Aldosteronism.

Introduction Primary aldosteronism is characterized by the autonomous excretion of aldosterone, which may induce bone mineral disorders. Methods A total of 96 patients with primary aldosteronism were analyzed to identify differences in the regulation of serum calcium/phosphate balance between patients with unilateral and bilateral aldosterone hypersecretion and to determine whether or not adrenalectomy or mineralocorticoid receptor blockers affected such differences. Results Serum phosphate concentrations were significantly lower in patients with unilateral aldosterone hypersecretion than in patients with bilateral aldosterone hypersecretion (2.96±0.45 vs. 3.36±0.55 mg/dL, p<0.05), and recovered after adrenalectomy (2.96±0.45 vs. 3.49±0.32 mg/dL, p<0.01). In patients with bilateral aldosterone hypersecretion, the baseline serum phosphate levels were significantly lower in responders to mineralocorticoid receptor blocker treatment, defined as post-treatment plasma renin activity ≥1 ng/mL/h, than in non-responders. In responders, these levels tended to recover after treatment. A weak negative correlation between the plasma aldosterone concentration (PAC) and serum phosphate was observed, but there were no associations between the PAC and serum calcium concentration or between the aldosterone renin ratio and serum calcium and phosphate concentrations. Conclusion The effects on calcium/phosphate homeostasis may differ according to the primary aldosteronism subtype.

Effect of esaxerenone on ischemia and reperfusion injury in rat hearts.

In myocardial infarction, the addition of mineralocorticoid receptor blockers (MRBs) to standard therapies, such as angiotensin-converting enzyme inhibitors or beta-blockers, reportedly reduces mortality and cardiac events. We investigated whether the non-steroidal MRB esaxerenone has cardioprotective effects and its protective mechanisms. Isolated rat hearts were Langendorff-perfused (constant pressure, 80 mmHg) with oxygenated Krebs-Henseleit bicarbonate buffer and reperfused for 60 min; afterwards, recovery of function (left ventricular pressure, measured with an intraventricular balloon) and myocardial injury were measured. In a preliminary study, we determined the optimal concentration of esaxerenone required for myocardial protection. Next, esaxerenone was administered in the pre- and post-ischemic phases to determine the optimal timing of administration. In addition, we assessed coronary flow response to acetylcholine (ACh) with and without esaxerenone. We examined whether esaxerenone-induced cardioprotection was prevented by targeting putative components in the preconditioning manner (the mitochondrial ATP-sensitive potassium (KATP) channel). Myocardial protection by esaxerenone was observed when esaxerenone was administered before ischemia but not after ischemia. The coronary flow response to ACh was significantly better in the esaxerenone group than in the control group. The cardioprotective effect of esaxerenone was eliminated by the mitochondrial KATP channel blocker, 5-hydroxy decanoate. This study confirmed the myocardial protective effect of the pre-ischemic administration of esaxerenone. Esaxerenone may contribute to coronary endothelial protection and exert pharmacological preconditioning via the mitochondrial KATP channel.

A selective mineralocorticoid receptor blocker, esaxerenone, attenuates vascular dysfunction and inhibits atherogenesis in apolipoprotein e-deficient mice

Abstract Introduction Pharmacological blockade of mineralocorticoid receptors (MR) is a potential therapeutic approach to reduce cardiovascular complications because MR play a crucial role in cardiovascular regulation. Recent studies suggest that MR antagonists affect several extrarenal tissues, including vascular function. We investigated the effects of a novel non-steroidal selective MR blocker, esaxerenone (ESAX), recently approved for hypertension treatment in Japan, on vascular function and the development of atherosclerosis. Methods and results ESAX (3mg/kg/day) or vehicle was orally administered to western type diet-fed apolipoprotein E-deficient mice for 20 weeks or for 8 weeks to investigate the effects on atherogenesis or vascular dysfunction. Administration of ESAX for 20 weeks suppressed the development of atherosclerotic plaques in the aortic arch compared with the vehicle group (p&amp;lt;0.001) without alteration of blood pressure. In addition, ESAX reduced the expression of intercellular cell adhesion molecule-1 (p&amp;lt;0.05), macrophage infiltration (p&amp;lt;0.01), lipid deposition (p&amp;lt;0.05) and tended to decrease the expression of vascular cell adhesion molecule-1 as determined by immunohistochemical analysis. Moreover, phosphorylation of eNOSSer1177 (p&amp;lt;0.05) and Akt (p&amp;lt;0.05) were increased in the aorta of ESAX-treated mice. Administration of ESAX for 8 weeks attenuated western type diet-induced endothelial dysfunction (p&amp;lt;0.05) accompanied with the decrease in expression of ICAM1 (p&amp;lt;0.05) and phosphorylation of JNK (p&amp;lt;0.05) in the descending aorta. In in vitro experiment, aldosterone decreased the phosphorylation of eNOSSer1177 and increased the phosphorylation of eNOSThr495 in a dose dependent manner, which were attenuated by ESAX in HUVECs. In ex vivo vascular reactivity assay, ESAX diminished the aldosterone-induced endothelial dysfunction. Conclusion ESAX ameliorated hyperlipidemia-induced atherosclerosis and vascular dysfunction in mice, suggesting that ESAX is a promising therapeutic approach for cardiovascular complications.

The Impact of Mineralocorticoid Receptor Blockers on Changes in Pulse Wave Velocity, Arterial Pressure and Heart Related Deaths in Hemodialysis Patients

The Impact of Mineralocorticoid Receptor Blockers on Changes in Pulse Wave Velocity, Arterial Pressure and Heart Related Deaths in Hemodialysis Patients

Exposure-response analysis of the efficacy and safety of esaxerenone, a novel nonsteroidal mineralocorticoid receptor blocker, in hypertensive patients with or without diabetic kidney disease

BackgroundEsaxerenone is a novel non-steroidal mineralocorticoid receptor blocker. Here, we assessed efficacy and safety exposure-response relationships of esaxerenone and its covariates and thereby justified the recommended dosage regimens, focusing on the safety benefits of up-titration regimen in patients at higher risk for increased serum potassium (sK+). MethodsThe relationships between model-derived individual esaxerenone exposure and efficacy (blood pressure [BP]) and safety (increased sK+) were evaluated using multivariate linear regression and Cox regression analyses, respectively, using data from 1453 hypertensive patients with or without diabetic kidney disease in five clinical studies. ResultsExposure-efficacy analyses demonstrated that higher exposure was linearly associated with greater BP reduction over the investigated dose range. Exposure-safety analyses showed that higher exposure was associated with a higher risk of increased sK+ under a fixed-dosing regimen; higher baseline sK+ and lower baseline estimated glomerular filtration rate (eGFR) were influential covariates. Model-based simulations suggested that fewer occurrences of increased sK+ are expected under the up-titration regimen (from 1.25 to 5 mg) relative to the fixed-dosing regimen (5 mg) in patients with different combinations of these covariates. ConclusionsThe exposure-response analyses supported the esaxerenone recommended doses and the safety benefits of using the up-titration regimen.

MicroRNA-155 mediates endogenous angiotensin II type 1 receptor regulation: implications for innovative type 2 diabetes mellitus management.

Type 2 diabetes mellitus (T2DM) is a lifelong condition and a threat to human health. Thorough understanding of its pathogenesis is acutely needed in order to devise innovative, preventative, and potentially curative pharmacological interventions. MicroRNAs (miRNA), are small, non-coding, one-stranded RNA molecules, that can target and silence around 60% of all human genes through translational repression. MiR-155 is an ancient, evolutionarily well-conserved miRNA, with distinct expression profiles and multifunctionality, and a target repertoire of over 241 genes involved in numerous physiological and pathological processes including hematopoietic lineage differentiation, immunity, inflammation, viral infections, cancer, cardiovascular conditions, and particularly diabetes mellitus. MiR-155 Levels are progressively reduced in aging, obesity, sarcopenia, and T2DM. Thus, the loss of coordinated repression of multiple miR-155 targets acting as negative regulators, such as C/EBPβ, HDAC4, and SOCS1 impacts insulin signaling, deteriorating glucose homeostasis, and causing insulin resistance (IR). Moreover, deranged regulation of the renin angiotensin aldo-sterone system (RAAS) through loss of Angiotensin II Type 1 receptor downregulation, and negated repression of ETS-1, results in unopposed detrimental Angiotensin II effects, further promoting IR. Finally, loss of BACH1 and SOCS1 repression abolishes cytoprotective, anti-oxidant, anti-apoptotic, and anti-inflammatory cellular pathways, and promotes β-cell loss. In contrast to RAAS inhibitor treatments that further decrease already reduced miR-155 Levels, strategies to increase an ailing miR-155 production in T2DM, e.g., the use of metformin, mineralocorticoid receptor blockers (spironolactone, eplerenone, finerenone), and verapamil, alone or in various combinations, represent current treatment options. In the future, direct tissue delivery of miRNA analogs is likely.

Esaxerenone Inhibits Renal Angiogenesis and Endothelial-Mesenchymal Transition via the VEGFA and TGF-β1 Pathways in Aldosterone-Infused Mice.

Renal fibrosis is an inevitable process in the progression of chronic kidney disease (CKD). Angiogenesis plays an important role in this process. Vascular endothelial cells are involved in renal fibrosis by phenotypic transformation and secretion of extracellular matrix. Aldosterone stimulates mineralocorticoid receptor (MR) activation and induces inflammation, which is important for angiogenesis. Clinically, MR blockers (MRBs) have a protective effect on damaged kidneys, which may be associated with inhibition of angiogenesis. In this study, we used aldosterone-infused mice and found that aldosterone induced angiogenesis and that endothelial-mesenchymal transition (EndMT) in neovascular endothelial cells was involved in renal fibrosis. Notably, aldosterone induced inflammation and stimulated macrophages to secrete vascular endothelial growth factor (VEGF) A to regulate angiogenesis by activating MR, whereas EndMT occurred in response to transforming growth factor-β1 (TGF-β1) induction and participated in renal fibrosis. These effects were antagonized by the MRB esaxerenone. These findings suggest that reducing angiogenesis may be an effective strategy for treating renal fibrosis.

Aldosterone Contributes to Vasopressin Escape through Changes in Water and Urea Transport.

Hyponatremia (hypo-osmolality) is a disorder of water homeostasis due to abnormal renal diluting capacity. The body limits the degree to which serum sodium concentration falls through a mechanism called "vasopressin escape". Vasopressin escape is a process that prevents the continuous decrease in serum sodium concentration even under conditions of sustained high plasma vasopressin levels. Previous reports suggest that aldosterone may be involved in the vasopressin escape mechanism. The abilities of aldosterone synthase (Cyp11b2) knockout and wild-type mice to escape from vasopressin were compared. Wild-type mice escaped while the aldosterone synthase knockout mice did not. Both the water channel aquaporin 2 (AQP2) and the urea transporter UT-A1 protein abundances were higher in aldosterone synthase knockout than in wild-type mice at the end of the escape period. Vasopressin escape was also blunted in rats given spironolactone, a mineralocorticoid receptor blocker. Next, the role of the phosphatase, calcineurin (protein phosphatase 2B, PP2B), in vasopressin escape was studied since aldosterone activates calcineurin in rat cortical collecting ducts. Tacrolimus, a calcineurin inhibitor, blunted vasopressin escape in rats compared with the control rats, increased UT-A1, AQP2, and pS256-AQP2, and decreased pS261-AQP2 protein abundances. Our results indicate that aldosterone regulates vasopressin escape through calcineurin-mediated protein changes in UT-A1 and AQP2.