Project description:Vascular damage is aggravated in animal models of hypertension with mineralocorticoid (MR) excess and in hypertensive patients with primary hyperaldosteronism. MR antagonism has shown to provide effective blood pressure (BP)-control in patients with treatment resistant hypertension (TRH), but the concurrent effects on the vasculature have not been examined. In a randomized, double-blinded, placebo-controlled parallel-group study, 51 patients with TRH received either eplerenone 50 mg or placebo for 6 months together with additional antihypertensives titrated to achieve a BP target of <140/90 mm Hg. Pulse wave velocity (PWV), augmentation index (AIx), augmentation pressure (AP), AP normalized to a heart rate of 75/min (AP@HR75), renal resistive index (RRI), intima-media thickness (IMT) and urinary albumin excretion rate (UAER) were assessed before and after treatment. PWV was reduced only with eplerenone (from 11.3±3.6 to 9.8±2.6 m/s, P˂.001), but not with placebo (10.3±2.0 to 10.1±1.8 m/s, P=.60), despite similar reductions in BP (-35±20/-15±11 mm Hg vs -30±19/-13±7 mm Hg, n.s.). Further, reductions in AP and AP@HR75 were greater with eplerenone, while changes in AIx, RRI, IMT and UAER were similar. Our data show that eplerenone beneficially affects markers of arterial stiffness and wave reflection in patients with TRH, independently of BP lowering. These data add to the evidence that MR antagonism should be the preferred treatment option in TRH.
Project description:This study investigated the effects and safety of eplerenone or thiazide diuretics in patients with hypertension and albuminuria (pretreatment urinary albumin/creatinine ratio ≥10 mg/gCr) treated with an angiotensin II receptor blocker. The primary end point was the mean percent change in the urinary albumin/creatinine ratio from baseline to 48 weeks. An efficacy analysis was performed in 195 patients (98 in the eplerenone group and 97 in the thiazide group). Systolic and diastolic blood pressures at 48 weeks were similar in the two groups. The mean percent change in the urinary albumin/creatinine ratio from baseline to 48 weeks was similar in the two groups (P=.804). In the safety analysis, the withdrawal rates for adverse events were similar in both groups. The antialbuminuric effects and safety of eplerenone therapy were similar to those of thiazide diuretics when combined with an angiotensin II receptor blocker in patients with hypertension and albuminuria.
Project description:BackgroundAldosterone is a mineralocorticoid hormone critically involved in arterial blood pressure regulation. Although pharmacological aldosterone antagonism reduces mortality and morbidity among patients with severe left-sided heart failure, the contribution of aldosterone to the pathobiology of pulmonary arterial hypertension (PAH) and right ventricular (RV) heart failure is not fully understood.MethodsThe effects of Eplerenone (0.1% Inspra® mixed in chow) on pulmonary vascular and RV remodeling were evaluated in mice with pulmonary hypertension (PH) caused by Sugen5416 injection with concomitant chronic hypoxia (SuHx) and in a second animal model with established RV dysfunction independent from lung remodeling through surgical pulmonary artery banding.ResultsPreventive Eplerenone administration attenuated the development of PH and pathological remodeling of pulmonary arterioles. Therapeutic aldosterone antagonism - starting when RV dysfunction was established - normalized mineralocorticoid receptor gene expression in the right ventricle without direct effects on either RV structure (Cardiomyocyte hypertrophy, Fibrosis) or function (assessed by non-invasive echocardiography along with intra-cardiac pressure volume measurements), but significantly lowered systemic blood pressure.ConclusionsOur data indicate that aldosterone antagonism with Eplerenone attenuates pulmonary vascular rather than RV remodeling in PAH.
Project description:EPLERENONE [SYSTEMATIC NAME: 7α-(methoxy-carbon-yl)-3-oxo-9α,11-ep-oxy-17α-pregn-4-ene-21,17-carbolactone], an aldo-sterone receptor antagonist, crystallizes from ethanol as a monosolvate, C(24)H(30)O(6)·C(2)H(6)O. The eplerenone mol-ecule has two five-membered rings, three six-membered rings and one three-membered ring. Both five-membered rings display envelope conformations, while the three six-membered rings assume envelope (cyclohexene), half-chair (cyclohexane sharing one edge with epoxy) and chair (other cyclohexane) conformations. The solvent mol-ecule is disordered equally over two sites. It is linked to the eplerenone mol-ecule by hydrogen bonds.
Project description:Hypertension is associated with endothelial dysfunction and activated Rho-associated kinases (ROCKs). The purpose of this study was to evaluate the effects of the selective mineralocorticoid receptor blocker, eplerenone, on endothelial function and ROCK activity in patients with hypertension. The study was carried out over 48 weeks in 60 untreated patients with hypertension who were randomly assigned to eplerenone, nifedipine, and losartan groups. We evaluated the effects of each treatment on flow-mediated vasodilation (FMD) and ROCK activity in peripheral leukocytes. Eplerenone increased FMD and decreased leukocyte ROCK activity. Nifedipine decreased ROCK activity but did not alter FMD. Losartan increased FMD but did not alter ROCK activity. Hypotensive effects were similar in the three groups, as was nitroglycerin-induced vasodilation during the follow-up period. There were no significant differences between the groups with respect to other parameters. The study results show that eplerenone improves endothelial function and inhibits ROCK activity in patients with essential hypertension.
Project description:The authors aimed to investigate the blood pressure (BP)-lowering ability of eplerenone in drug-resistant hypertensive patients. A total of 57 drug-resistant hypertensive patients whose home BP was ≥135/85 mm Hg were investigated. The patients were randomized to either an eplerenone group or a control group and followed for 12 weeks. The efficacy was evaluated by clinic, home, and ambulatory BP monitoring. Urinary albumin, pulse wave velocity, and flow-mediated vasodilation (FMD) were also evaluated. Home morning systolic BP (148±15 vs 140±15 mm Hg) and evening systolic BP (137±16 vs 130±16 mm Hg) were significantly lowered in the eplerenone group (n=35) compared with baseline (both P<.05), while unchanged in the control group (n=22). BP reductions in the eplerenone group were most pronounced for ambulatory awake systolic BP (P=.04), awake diastolic BP (P=.004), and 24-hour diastolic BP (P=.02). FMD was significantly improved in the eplerenone group. In patients with drug-resistant hypertension, add-on use of eplerenone was effective in lowering BP, especially home and ambulatory awake BP.
Project description:Conventionally, rennin-angiotensin-aldosterone system (RAAS) inhibition has focused on angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers and angiotensin receptor-neprilysin inhibitors (ARNI) are the latest addition to this armamentarium. However, mineralocorticoid receptor antagonists (MRAs) also constitute an integral part of this anti-RAAS brigade, which are perceived more often as diuretics and are often under prescribed in heart failure (HF) despite being universally advocated by all major guidelines. Apart from HF, they have also shown promise in the management of hypertension, post-myocardial infarction, and hyperaldosteronism. Eplerenone, Food and Drug Administration (FDA) approved in 2002, is an acceptable alternative to spironolactone due to its sparing androgenic effects. In two big pivotal trials in heart failure (EMPHASIS -HF) and post-myocardial infarction (EPHESUS), the drug has firmly shown a reduction in adverse cardiovascular events. It has an established place in the management of resistant hypertension too. In this article, we will discuss the role of RAAS and its pathophysiology, pitfalls of spironolactone, which led to success of its congener, eplerenone, major studies conducted on eplerenone, current role of eplerenone, and comparison of the two MRAs.
Project description:The obstructive sleep apnea (OSA) is highly associated with various significant cardiovascular outcomes such as resistant hypertension (RAH). Despite this, as of now the relationship between high night-time blood pressure (BP) and left ventricular hypertrophy (LVH) in patients with OSA and RAH is not fully understood. The aim of this study was to assess the influence of the addition of eplerenone to a standard antihypertensive therapy on parameters of 24-h ambulatory blood pressure measurement (ABPM) as well as on the results of echocardiography and polysomnography in patients with OSA and RAH. The patients were randomly assigned to one of the two study groups: the treatment group, receiving 50 mg/d eplerenone orally for 6 months (n = 51) and the control group, remaining on their standard antihypertensive therapy (n = 51). After that period, a significant reduction in the night-time BP parameters in the treatment group including an increased night blood pressure fall from 4.6 to 8.9% was noted. Additionally, the number of non-dipper patients was reduced by 45.1%. The treatment group also revealed a decrease in left ventricular hypertrophy and in the apnea-hypopnea index (AHI) with a positive correlation being observed between these two parameters. This study is the first to report the improvement of the circadian BP profile and the improvement of the left ventricle geometry in patients with OSA and RAH following the addition of selective mineralocorticoid receptor antagonists to antihypertensive therapy.
Project description:BACKGROUND:The aldosterone inhibitor eplerenone (EPL) has been shown to reduce the incidence of atrial fibrillation (AF) in patients with systolic heart failure, but the mechanism is unknown. OBJECTIVES:This study hypothesized that by reducing atrial dilation and fibrosis in the absence of heart failure, EPL also reduces AF burden and prevents AF perpetuation. METHODS:The authors conducted a randomized controlled study in 34 sheep that were atrially tachypaced (13 ± 1 week). They compared daily oral EPL (n = 19) versus sugar pill (SP) treatment (n = 15) from the start of tachypacing. The endpoint was a continuous 7-day stretch of persistent AF (n = 29) or completion of 23 weeks tachypacing (n = 5). RESULTS:EPL significantly reduced the rate of left atrial dilation increase during AF progression. Atria from EPL-treated sheep had less smooth muscle actin protein, collagen-III expression, interstitial atrial fibrosis, and cell hypertrophy than SP-treated sheep atria did. However, EPL did not modify the AF-induced increase in the rate of dominant frequency and ion channel densities seen under SP treatment, but rather prolonged the time to persistent AF in 26% of animals. It also reduced the degree of fibrillatory conduction, AF inducibility, and AF burden. CONCLUSIONS:In the sheep model, EPL mitigates fibrosis and atrial dilation, modifies AF inducibility and AF complexity, and prolongs the transition to persistent AF in 26% of animals, but it does not prevent AF-induced electrical remodeling or AF persistence. The results highlight structural remodeling as a central upstream target to reduce AF burden, and the need to prevent electrical remodeling to avert AF perpetuation.
Project description:Poor aqueous solubility of eplerenone (EPL) is a major obstacle to achieve sufficient bioavailability after oral administration. In this study, we aimed to develop and evaluate eplerenone nanocrystals (EPL-NCs) for solubility and dissolution enhancement. D-optimal combined mixture process using Design-Expert software was employed to generate different combinations for optimization. EPL-NCs were prepared by a bottom-up, controlled crystallization technique during freeze-drying. The optimized EPL-NCs were evaluated for their size, morphology, thermal behavior, crystalline structure, saturation solubility, dissolution profile, in vivo pharmacokinetics, and acute toxicity. The optimized EPL-NCs showed mean particle size of 46.8 nm. Scanning electron microscopy revealed the formation of elongated parallelepiped shaped NCs. DSC and PXRD analysis confirmed the crystalline structure and the absence of any polymorphic transition in EPL-NCs. Furthermore, EPL-NCs demonstrated a 17-fold prompt increase in the saturation solubility of EPL (8.96 vs. 155.85 µg/mL). The dissolution rate was also significantly higher as indicated by ∼95% dissolution from EPL-NCs in 10 min compared to only 29% from EPL powder. EPL-NCs improved the oral bioavailability as indicated by higher AUC, Cmax, and lower Tmax than EPL powder. Acute oral toxicity study showed that EPL-NCs do not pose any toxicity concern to the blood and vital organs. Consequently, NCs prepared by controlled crystallization technique present a promising strategy to improve solubility profile, dissolution velocity and bioavailability of poorly water-soluble drugs.