Selection of a mineralocorticoid receptor antagonist for patients with hypertension or heart failure

Comparative Analysis of The Effectiveness of Antihypertensive Therapy Including Spironolactone and Eplerenone in Patients With Essential Hypertension and Atrial Fibrillation

AIM

To perform a comparative analysis of the efficacy of antihypertensive therapy (AHT) containing spironolactone or eplerenone in patients with essential arterial hypertension (AH) and atrial fibrillation (AF).

MATERIAL AND METHODS

The study included 99 male and female patients with essential AH complicated by permanent AF, who were receiving the outpatient treatment at the National Specialized Scientific and Practical Medical Center of Cardiology (Tashkent). The patients aged 61.3±9.5 years, the mean duration of AH was 12.9±8.3 years. All patients were divided into two groups: Group 1, patients who completed a 6-month combination AHT containing spironolactone (n=51); Group 2, patients who completed a 6-month combination AHT containing eplerenone (n=48). AF was diagnosed by electrocardiogram (ECG) and/or 24-hour ECG monitoring according to standard diagnostic criteria. The ECG study was performed in compliance with the American Society of Echocardiography Guidelines in M- and B-modes. The degree of structural vascular alterations was determined by the intima-media thickness of the common carotid artery by duplex scanning and microalbuminuria in morning urine. The concentrations of sex hormones were measured by the enzyme immunoassay. The serum concentrations of lipids, glucose, creatinine, and uric acid were measured by the enzymatic method. The glomerular filtration rate (GFR) was calculated with the EPI formula. Results of all studies were considered statistically significant at p<0.05.

RESULTS

The proportion of patients who achieved the target diastolic blood pressure (BP) values was significantly greater in the eplerenone-containing treatment group than in the spironolactone-containing treatment group: 87.8% vs. 67.5% (p=0.043). The proportion of patients who simultaneously achieved the target systolic and diastolic BP values was slightly greater in the eplerenone-containing treatment group than in the spironolactone-containing group (100% vs. 92.1%, p=0.060). The best cardioprotective efficacy was observed in the group of combination AHT containing eplerenone. Specifically, in Group 2, the left ventricular ejection fraction (LVEF) was significantly improved compared to Group 1: from 55.4±10.6% at baseline to 52.6±9.1% in Group 1 (p>0.05) and from 54.8±8.8% at baseline to 58.2±6.4% in Group 2 (p<0.02). Only in Group 2, the left atrial volume index (LAVI) was significantly decreased compared to Group 1. Thus, in Group 1, the LAVI changed from 42.2±15.1 ml/m2 at baseline to 40.4±12.2 ml/m2 (p>0.05) and in Group 2, from 41.2±15.3 ml/m2 at baseline to 37.3±13.5 ml/m2 after the treatment (p<0.05); the ∆% LAVI in the eplerenone group was -5.9% vs. -0.36% in the spironolactone group. In men of Group 1, estradiol significantly increased from 13.9±12.6 pmol/l at baseline to 22.7±12.4 pmol/l (p<0.001).

CONCLUSION

The good antihypertensive efficacy of the 6-month combination therapy containing eplerenone was significantly superior to spironolactone in achieving the target BP values. The eplerenone-containing treatment significantly improved LVEF and decreased LAVI compared to the spironolactone-containing treatment. A trend towards a beneficial effect of the AHT containing eplerenone on concentrations of sex hormones was noted in both women and men.

Comparative effectiveness and safety of eplerenone and spironolactone in patients with heart failure: a systematic review and meta-analysis

BACKGROUND

Eplerenone and spironolactone, recognized as mineralocorticoid receptor antagonists (MRAs), have been reported to improve clinical prognosis among individuals diagnosed with heart failure (HF). However, the difference in the clinical effects between eplerenone and spironolactone in individuals with HF remains uncertain. We aimed to assess the impact of eplerenone compared to spironolactone on clinical outcomes within the HF population.

METHODS

An extensive search was executed in several databases (PubMed, Web of Science, Scopus, Cochrane Library). All relevant studies evaluating eplerenone compared to spironolactone in patients with HF were included. Dichotomous data were pooled as Hazard ratio (HR) or Risk ratio (RR) with a 95% confidence interval (CI). Our main outcome was all-cause mortality. Secondary outcomes included death from cardiovascular causes, treatment withdrawal, and gynecomastia.

RESULTS

Ten studies, comprising 21,930 HF individuals, were included in our investigation. Eplerenone showed a lower risk of all-cause mortality (HR = 0.78, 95%CI [0.64 to 0.94], P = 0.009) and cardiovascular mortality (HR = 0.54, 95%CI [0.39, 0.74], P = 0.0001) compared to spironolactone. Furthermore, eplerenone exhibited a reduced risk of treatment withdrawal (RR = 0.69, 95% CI [0.62, 0.78], P = 0.0001) and gynecomastia (RR = 0.07, 95% CI [0.02 to 0.31], P = 0.0001) than spironolactone.

CONCLUSION

Eplerenone revealed lower all-cause and cardiovascular mortality events in comparison to spironolactone. Moreover, eplerenone was associated with lower gynecomastia and treatment withdrawal events compared to spironolactone. Further well-designed randomized controlled trials are still warranted better to identify the clinical differences between eplerenone and spironolactone.

TRIAL REGISTRATION

Protocol registration: https://doi.org/10.17605/OSF.IO/VNMGK.

Enzalutamide: Understanding and Managing Drug Interactions to Improve Patient Safety and Drug Efficacy

Enzalutamide is an oral androgen receptor signaling inhibitor utilized in the treatment of men with prostate cancer. It is a moderate inducer of the cytochrome P450 (CYP) enzymes CYP2C9 and CYP2C19, and a strong inducer of CYP3A4. It was also shown to be a mild inhibitor of the efflux transporter P-glycoprotein in patients with prostate cancer. Enzalutamide is primarily metabolized by CYP3A4 and CYP2C8. The risk of enzalutamide drug interactions arises primarily when it is coadministered with other drugs that interact with these CYPs, including CYP3A4. In this review, we begin by providing an overview of enzalutamide including its dosing, use in special populations, pharmacokinetics, changes to its prescribing information, and potential for interaction with coadministered drugs. Enzalutamide interactions with drugs from a wide range of medication classes commonly prescribed to patients with prostate cancer are described, including oral androgen deprivation therapy, agents used to treat a range of cardiovascular diseases, antidiabetic drugs, antidepressants, anti-seizure medications, common urology medications, analgesics, proton pump inhibitors, immunosuppressants, and antigout drugs. Enzalutamide interactions with common vitamins and supplements are also briefly discussed. This review provides a resource for healthcare practitioners and patients that will help provide a basis for the understanding and management of enzalutamide drug-drug interactions to inform decision making, improve patient safety, and optimize drug efficacy.

The Effectiveness of Eplerenone vs Spironolactone on Left Ventricular Systolic Function, Hospitalization and Cardiovascular Death in Patients With Chronic Heart Failure-HFrEF

Background

Heart failure remains one of the most prevalent clinical syndromes associated with significant morbidity and mortality. According to current guidelines, the prescription of a MRA is recommended to reduce the risk of HF hospitalization and death in all patients with symptomatic heart failure and no contraindications for this therapy.

Objective

The aim of our study was to determine the efficacy of eplerenone vs. spironolactone on left ventricular systolic function by measuring left ventricle ejection fraction (LVEF) in patients with chronic heart failure, especially their effect on preventing hospitalization, reducing mortality, and improving clinical status among patients with chronic HF.

Methods

From June 2021 to June 2022, the study was a randomized, prospective clinical trial single blind study. A total of 142 patients of chronic heart failure with reduced ejection fraction were selected by random sampling. Each patient was randomly allocated into either of the two groups and was continued receiving treatment with either spironolactone (Spiron-HF group) or eplerenone (Epler-HF group). Patients in Epler-HF group were compared with an arm of the same size and matched by age and gender patients in Spiron-HF group for management of chronic HFrEF. Each patient was evaluated clinically, biochemically, and echocardiographically at the beginning of treatment (baseline) after 6 months and at the end of 12th month. Echocardiography was performed to find out change in left ventricular systolic function.

Results

After 12 months of treatment, significant improvement of left ventricular ejection fraction was observed in eplerenone treated arm (37.9 ± 3.8 ± 4.6 in Spiron-HF group versus 40.1 ± 5.7 in Epler-HF group; P < 0.05). A significant reduction in left ventricular end-systolic volume (6.3 ± 2.5ml in Spiron-HF versus 17.8± 4.4ml in Epler-HF group; P < 0.05) and left ventricular systolic diameter volume (2.7 ± 0.5ml in Spiron-HF versus 6.7 ± 0.2ml in Epler-HF group; P < 0.05), occurred after 12 months of treatment. Left ventricular global longitudinal strain (LV GLS) was significantly improved in Epler-HF group compared with Spiron-HF group (0.6 ± 0.4 versus 3.4 ± 0.9; P < 0.05). There were no significant differences observed in reduction of left ventricular end-diastolic volume (2.2 ± 0.5 ml versus 4.7 ± 1.1ml; P =0.103) and left ventricular diastolic diameter (1.2 ± 0.6 versus 1.7 ± 0.3; P=0.082) in both arms. The effects of both MRA agents spironolactone and eplerenone on the primary composite outcome, each of the individual mortality and hospital admission outcomes are shown in Figure 1 and 2. Patients of the Epler-HF group showed statistically significant lower cardiovascular mortality (HR 0.53; 95% CI 0.34-0.82; p= 0.007) and all-cause mortality (HR 0.64; 95% CI 0.44-0.93; p= 0.022) than patients of the Spiron-HF group. The statistical analysis did not show a statistically significant difference between Epler -HF and Spiron-HF study groups regarding the risk of the primary composite outcome; cardiovascular death or hospitalization due to HF (Hazard Ratio (HR) eplerenone vs. spironolactone = 0.95; 95% Confidence Interval (CI) 0.73- 1.27; p= 0.675).

Conclusion

Our study has demonstrated favorable effects of eplerenone on cardiac remodeling parameters and reduction of cardiovascular mortality and all-cause mortality compared with spironolactone in the treatment of HFrEF. The ability of eplerenone to effectively block the mineralocorticoid receptor while minimizing side effects and a significant reduction in the risk of hospitalization and cardiovascular death confirms its key role in the treatment of patients with chronic HFrEF.

Steroidal MRA Across the Spectrum of Renal Function: A Pooled Analysis of RCTs

BACKGROUND

Mineralocorticoid receptor antagonists (MRAs) are underused in patients with kidney dysfunction, and their efficacy among patients with chronic kidney disease (CKD) is uncertain.

OBJECTIVES

The goal of this study was to analyze the efficacy and safety of steroidal MRAs across the spectrum of estimated glomerular filtration rates (eGFRs) in randomized controlled trials. The study included patients with heart failure (HF) or myocardial infarction and advanced CKD who participated in the RALES (Randomized Aldactone Evaluation Study), EMPHASIS-HF (Eplerenone in Mild Patients Hospitalization and Survival Study in Heart Failure), TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) in the Americas, and EPHESUS (Eplerenone Post-AMI Heart Failure Efficacy and Survival Study) trials.

METHODS

This study used individual patient data meta-analysis using Cox models stratified by trial with treatment-by-eGFR interaction terms. eGFR was recalculated by using the Chronic Kidney Disease Epidemiology Collaboration creatinine formula.

RESULTS

A total of 12,700 patients were included, of whom 331 (2.6%) had an eGFR ≤30 mL/min/1.73 m² (mean eGFR: 26.8 ± 3.2 mL/min/1.73 m²). Patients with advanced CKD had higher annualized event rates for all studied outcomes: placebo event rate for the composite of cardiovascular death or HF hospitalization was ∼3-fold higher in patients with eGFR ≤30 compared with those with eGFR >90 mL/min/1.73 m²: 41.6 vs 14.6 events per 100 person-years. MRAs (vs placebo) reduced the composite of cardiovascular death or HF hospitalization, but the effect was attenuated as eGFR decreased: the corresponding HRs by eGFR categories were: HR for >90 mL/min/1.73 m²: 0.62 (95% CI: 0.49-0.78); HR for 61-90 mL/min/1.73 m²: 0.69 (95% CI: 0.61-0.77); HR for 46-60 mL/min/1.73 m²: 0.84 (95% CI: 0.74-0.95); HR for 31-45 mL/min/1.73 m²: 0.79 (95% CI: 0.68-0.91); and HR for ≤30 mL/min/1.73 m²: 0.96 (95% CI: 0.70-1.32) (treatment-by-eGFR interaction P for trend = 0.033). Investigator-reported hyperkalemia and worsening renal function were more frequent (2- to 3-fold) among MRA users, and hyperkalemia was more frequent as eGFR decreased (treatment-by-eGFR interaction P for trend = 0.002).

CONCLUSIONS

Steroidal MRAs reduced HF hospitalizations and mortality across a wide range of eGFR. However, declining benefit and worsening safety may limit their use in patients with lower eGFR, particularly those with levels ≤30 mL/min/1.73 m².

Real world comparison of spironolactone and eplerenone in patients with heart failure

AIMS

In the absence of previous direct comparative studies, we aimed to evaluate the effectiveness of spironolactone and eplerenone in patients with heart failure and reduced ejection fraction (HFrEF) in a real-world clinical setting.

METHODS

Using Fine-Gray´s competing risk regression, we compared the clinical outcomes of 293 patients with chronic HF and left ventricular ejection fraction <40% treated with eplerenone and 293 propensity-score matched individuals treated with spironolactone. Study subjects were selected from a prospective cohort of 1404 ambulatory patients with HFrEF seen since 2010 to 2019 in a single specialized HF clinic, among which 992 received a mineralocorticoid receptor antagonist at baseline. Median follow-up was 3.95 years.

RESULTS

No statistically significant differences between patients treated with eplerenone versus spironolactone were observed with regard to the risk of the primary composite end-point cardiovascular death or HF hospitalization (HR 0.95; 95% CI 0.73-1.23; p= 0.677). However, eplerenone use was associated to lower cardiovascular mortality (HR 0.55; 95% CI 0.35-0.85; p= 0.008) and lower all-cause mortality (HR 0.67; 95% CI 0.47-0.95; p= 0.027). The incidence of drug suspension due to side effects (HR 0.58, 95% CI 0.40-0.85; p= 0.005) and drug suspension due to any reason (HR 0.70, 95% CI 0.51-0.97; p= 0.033) were lower among patients treated with eplerenone.

CONCLUSIONS

In this observational, real-world, propensity-score matched study of patients with HFrEF, eplerenone was associated to lower cardiovascular mortality and lower all-cause mortality than spironolactone.

MRAs in Elderly HF Patients: Individual Patient-Data Meta-Analysis of RALES, EMPHASIS-HF, and TOPCAT

OBJECTIVES

This study sought to assess the effect of MRA treatment (vs. placebo) in older patients (≥75 years of age) compared with younger patients (<75 years of age) with heart failure (HF).

BACKGROUND

Mineralocorticoid receptor antagonists (MRAs) have been shown to reduce morbidity and mortality in patients with HF with reduced ejection fraction (HFrEF) and in a subset of patients with HF with preserved EF (HFpEF). Notwithstanding, MRAs are underused, especially in the elderly. Pooling the individual patient data (IPD) provided more statistical power with which to assess the efficacy and safety of MRA treatment in this subpopulation.

METHODS

An IPD meta-analysis was performed using Cox proportional hazards models stratified by trial. A total of 1,756 patients (853 randomized to placebo and 903 to MRA) ≥75 years of age, along with 4,411 patients (2,242 randomized to placebo and 2,169 to MRA) <75 years of age were included. The primary outcome was a composite of death from cardiovascular causes or hospitalization for HF.

RESULTS

The treatment groups were well balanced. Patients ≥75 years of age or older and those 80 years of age, 61% were male, 30% had diabetes, and the mean estimated glomerular filtration rate 59 ml/min. The primary outcome occurred in 331 patients (38.8%) in the placebo group versus 281 (31.1%) in the MRA group (hazard ratio: 0.74; 95% confidence interval: 0.63 to 0.86; p < 0.001; and the heterogeneity p value [heterogeneity p = Cochran's Q p value of treatment effect by study interaction] was 0.52). Cardiovascular death and all-cause death were also reduced by MRAs without significant between-trial or age (younger vs. older) heterogeneity. Worsening renal function and hyperkalemia occurred more frequently in patients taking MRAs (vs. placebo). Compared to younger patients, worsening renal function (but not hyperkalemia) was found more frequently in the elderly.

CONCLUSIONS

MRAs reduced morbidity and mortality in elderly patients with HF, a beneficial effect that is more marked in patients with HFrEF but homogenous across HFrEF and HFpEF. Implementation of measures that increase MRA treatment in this population are warranted.

Patient characteristics and initiation of mineralocorticoid receptor antagonists in patients with chronic kidney disease in routine clinical practice in the US: a retrospective cohort study

Background

Steroidal mineralocorticoid receptor antagonists (MRAs) are recommended for the treatment of heart failure (HF) and resistant hypertension, both common comorbidities in patients with diabetes and chronic kidney disease (CKD). This study explored the clinical characteristics of, and steroidal MRA use in, patients with CKD with and without type 2 diabetes mellitus (T2D) and/or HF.

Methods

This retrospective cohort study used PharMetrics Plus US claims database data (October 2009–September 2014) to identify two patient populations aged ≥18 years with a first diagnosis of CKD or a first prescription for steroidal MRAs. Demographic characteristics, comorbidities, clinical events, medication use and healthcare costs were reported by population and stratified by diagnosis: CKD, CKD + T2D (DKD), CKD + HF and DKD + HF. The CKD population cohorts were further stratified by steroidal MRA treatment duration (no MRAs, < 6 and ≥ 6 months’ treatment).

Results

The CKD and MRA populations comprised 229,004 patients and 5899 patients, respectively. Median age and the proportion of men were similar in the CKD and MRA populations across disease cohorts. Disease burden increased across the cohorts as comorbidity and clinical event incidences increased. Hypertension was reported in 70–92% of patients, irrespective of disease cohort or population. In the CKD population, MRA use was low but increased with disease burden: CKD, 1.2%; DKD, 1.8%; CKD + HF, 6.5%; and DKD + HF, 6.6%. Moreover, MRA users presented with higher rates of comorbidities and medication use, and higher healthcare costs than MRA non-users. Longer MRA treatment duration was associated with reduced polypharmacy, lower event rates and lower healthcare costs. In the MRA population, patients almost exclusively received spironolactone (≥ 96%; median dose across all groups 25 mg; one-year persistence, ≤ 43%); up to 16% of patients had end-stage renal disease at baseline despite steroidal MRAs being contraindicated.

Conclusions

Steroidal MRA use was low across all cohorts, but increased with disease severity, driven particularly by HF. Steroidal MRAs were used in patients with advanced CKD, despite being contraindicated. The persistent morbidity and clinical event rates in CKD and DKD patients highlight the disease burden and the need for treatments that effectively target both cardio-vascular and kidney-related events.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1348-4) contains supplementary material, which is available to authorized users.

Preclinical pharmacology of AZD9977: A novel mineralocorticoid receptor modulator separating organ protection from effects on electrolyte excretion

Excess mineralocorticoid receptor (MR) activation promotes target organ dysfunction, vascular injury and fibrosis. MR antagonists like eplerenone are used for treating heart failure, but their use is limited due to the compound class-inherent hyperkalemia risk. Here we present evidence that AZD9977, a first-in-class MR modulator shows cardio-renal protection despite a mechanism-based reduced liability to cause hyperkalemia. AZD9977 in vitro potency and binding mode to MR were characterized using reporter gene, binding, cofactor recruitment assays and X-ray crystallopgraphy. Organ protection was studied in uni-nephrectomised db/db mice and uni-nephrectomised rats administered aldosterone and high salt. Acute effects of single compound doses on urinary electrolyte excretion were tested in rats on a low salt diet. AZD9977 and eplerenone showed similar human MR in vitro potencies. Unlike eplerenone, AZD9977 is a partial MR antagonist due to its unique interaction pattern with MR, which results in a distinct recruitment of co-factor peptides when compared to eplerenone. AZD9977 dose dependently reduced albuminuria and improved kidney histopathology similar to eplerenone in db/db uni-nephrectomised mice and uni-nephrectomised rats. In acute testing, AZD9977 did not affect urinary Na+/K+ ratio, while eplerenone increased the Na+/K+ ratio dose dependently. AZD9977 is a selective MR modulator, retaining organ protection without acute effect on urinary electrolyte excretion. This predicts a reduced hyperkalemia risk and AZD9977 therefore has the potential to deliver a safe, efficacious treatment to patients prone to hyperkalemia.

Heart failure 2016: still more questions than answers

Heart failure has reached epidemic proportions given the ageing of populations and is associated with high mortality and re-hospitalization rates. This article reviews and summarizes recent advances in the diagnosis, assessment and treatment of the patients with heart failure. Data are discussed based also on the most recent guidelines indications. Open issues and unmet needs are highlighted.

Vascular mineralocorticoid receptor regulates microRNA-155 to promote vasoconstriction and rising blood pressure with aging

Hypertension is nearly universal yet poorly controlled in the elderly despite proven benefits of intensive treatment. Mice lacking mineralocorticoid receptors in smooth muscle cells (SMC-MR-KO) are protected from rising blood pressure (BP) with aging, despite normal renal function. Vasoconstriction is attenuated in aged SMC-MR-KO mice, thus they were used to explore vascular mechanisms that may contribute to hypertension with aging. MicroRNA (miR) profiling identified miR-155 as the most down-regulated miR with vascular aging in MR-intact but not SMC-MR-KO mice. The aging-associated decrease in miR-155 in mesenteric resistance vessels was associated with increased mRNA abundance of MR and of predicted miR-155 targets Cav1.2 (L-type calcium channel (LTCC) subunit) and angiotensin type-1 receptor (AgtR1). SMC-MR-KO mice lacked these aging-associated vascular gene expression changes. In HEK293 cells, MR repressed miR-155 promoter activity. In cultured SMCs, miR-155 decreased Cav1.2 and AgtR1 mRNA. Compared to MR-intact littermates, aged SMC-MR-KO mice had decreased systolic BP, myogenic tone, SMC LTCC current, mesenteric vessel calcium influx, LTCC-induced vasoconstriction and angiotensin II-induced vasoconstriction and oxidative stress. Restoration of miR-155 specifically in SMCs of aged MR-intact mice decreased Cav1.2 and AgtR1 mRNA and attenuated LTCC-mediated and angiotensin II-induced vasoconstriction and oxidative stress. Finally, in a trial of MR blockade in elderly humans, changes in serum miR-155 predicted the BP treatment response. Thus, SMC-MR regulation of miR-155, Cav1.2 and AgtR1 impacts vasoconstriction with aging. This novel mechanism identifies potential new treatment strategies and biomarkers to improve and individualize antihypertensive therapy in the elderly.

Systems Pharmacology Dissection of the Integrated Treatment for Cardiovascular and Gastrointestinal Disorders by Traditional Chinese Medicine

Though cardiovascular diseases (CVDs) and gastrointestinal disorders (GIDs) are different diseases associated with different organs, they are highly correlated clinically. Importantly, in Traditional Chinese Medicine (TCM), similar treatment strategies have been applied in both diseases. However, the etiological mechanisms underlying them remain unclear. Here, an integrated systems pharmacology approach is presented for illustrating the molecular correlations between CVDs and GIDs. Firstly, we identified pairs of genes that are associated with CVDs and GIDs and found that these genes are functionally related. Then, the association between 115 heart meridian (HM) herbs and 163 stomach meridian (SM) herbs and their combination application in Chinese patent medicine was investigated, implying that both CVDs and GIDs can be treated by the same strategy. Exemplified by a classical formula Sanhe Decoration (SHD) treating chronic gastritis, we applied systems-based analysis to introduce a drug-target-pathway-organ network that clarifies mechanisms of different diseases being treated by the same strategy. The results indicate that SHD regulated several pathological processes involved in both CVDs and GIDs. We experimentally confirmed the predictions implied by the effect of SHD for myocardial ischemia. The systems pharmacology suggests a novel integrated strategy for rational drug development for complex associated diseases.

[Mineralocorticoid receptor antagonists in the treatment of patients with chronic heart failure. Positions in 2015]

Mineralocorticoid receptor antagonists (MCRA) are part of standard medical therapy for heart failure (HF). The clinical efficacy of MCRA in patients with systolic HF has been proven by randomized clinical trials. The efficacy of this drug group in patients with chronic HF with preserved left ventricular systolic function and the advent and practical introductions of safer new-generation MCRA remain to be answered.

Efficacy of mineralocorticoid receptor antagonism in the acute myocardial infarction phase: eplerenone versus spironolactone

AIMS

The selective mineralocorticoid receptor (MR) antagonist eplerenone given early in patients with acute myocardial infarction (MI) improves clinical outcome, whereas little is known about the effectiveness of early spironolactone therapy. We aimed to compare the ability of eplerenone and spironolactone to promote cardiac repair after experimental MI.

METHODS AND RESULTS

Starting immediately after coronary artery ligation, C57BL/6J mice were treated with placebo, eplerenone, or spironolactone. At 7 days, treatment with eplerenone or spironolactone reduced thinning and expansion of healing infarct and improved early left ventricular chamber enlargement. Remarkably, eplerenone therapy resulted in significantly greater improvement than spironolactone of left ventricular contractile function and relaxation, associated with a more considerable leftward and downward shift of the pressure volume curve. Seven-day survival rate was significantly increased only in eplerenone treated mice. Moreover, eplerenone was superior to spironolactone in ameliorating neovessel formation in the injured myocardium. Optimized flow cytometry analysis of the monocyte differentiation marker Ly6C revealed predominant accumulation of Ly6Chigh monocytes/macrophages at the site of ischemic injury during the early inflammatory phase in placebo-treated mice. In contrast, MR antagonism, especially by eplerenone, led to a skewing of the monocyte/macrophage population toward a higher frequency of healing promoting Ly6Clow cells.

CONCLUSION

The MR antagonist eplerenone versus spironolactone showed superior efficacy during the acute MI phase with more beneficial effects on survival, early cardiac dilation, and functional decline. Modulation of monocyte maturation and enhanced infarct neovessel formation appears to play a pivotal role.

Berberine attenuates adverse left ventricular remodeling and cardiac dysfunction after acute myocardial infarction in rats: role of autophagy

The present study aimed to test the hypothesis that berberine, a plant-derived anti-oxidant, attenuates adverse left ventricular remodelling and improves cardiac function in a rat model of myocardial infarction (MI). Furthermore, the potential mechanisms that mediated the cardioprotective actions of berberine, in particular the effect on autophagy, were also investigated. Acute MI was induced by ligating the left anterior descending coronary artery of Sprague-Dawley rats. Cardiac function was assessed by transthoracic echocardiography. The protein activity/levels of autophagy related to signalling pathways (e.g. LC-3B, Beclin-1) were measured in myocardial tissue by immunohistochemical staining and western blot. Four weeks after MI, berberine significantly prevented cardiac dysfunction and adverse cardiac remodelling. MI rats treated with low dose berberine (10 mg/kg per day) showed higher left ventricular ejection fraction and fractional shortening than those treated with high-dose berberine (50 mg/kg per day). Both doses reduced interstitial fibrosis and post-MI adverse cardiac remodelling. The cardioprotective action of berberine was associated with increased LC-3B II and Beclin-1 expressions. Furthermore, cardioprotection with berberine was potentially related to p38 MAPK inhibition and phospho-Akt activation. The present in vivo study showed that berberine is effective in promoting autophagy, and subsequently attenuating left ventricular remodelling and cardiac dysfunction after MI. The potential underlying mechanism is augmentation of autophagy through inhibition of p38 MAPK and activation of phospho-Akt signalling pathways.

Emerging cardiovascular indications of mineralocorticoid receptor antagonists

Mineralocorticoid receptor (MR) antagonism is a well-established treatment modality for patients with hypertension, heart failure, and left ventricular systolic dysfunction (LVSD) post-myocardial infarction (MI). There are emerging data showing potential benefits of MR antagonists in other cardiovascular conditions. Studies have shown association between MR activation and the development of myocardial fibrosis, coronary artery disease, metabolic syndrome, and cerebrovascular diseases. This review examines the preclinical and clinical data of MR antagonists for novel indications including heart failure with preserved ejection fraction (HFPEF), pulmonary arterial hypertension (PAH), arrhythmia, sudden cardiac death, valvular heart disease, metabolic syndrome, renal disease, and stroke. MR antagonists are not licensed for these conditions yet; however, emerging data suggest that indication for MR antagonists are likely to broaden; further studies are warranted.