A number of marketed dihydropyridine calcium channel blockers have mineralocorticoid receptor antagonist activity

Clinical Management of Primary Aldosteronism: An Update

Despite carrying an excess risk of cardiovascular events, primary aldosteronism (PA) is a commonly overlooked secondary form of arterial hypertension. An increased awareness of its high prevalence and broader screening strategies are urgently needed to improve its detection rate and allow early diagnosis and targeted treatment. For patients with unilateral PA, these measures can correct hyperaldosteronism and ensure cure of hypertension, even when resistant to drug treatment, thus preventing adverse cardiovascular events. Among these, atrial fibrillation is the most common, but left ventricular hypertrophy, stroke, chronic kidney disease, and myocardial infarction also occur more often than in patients with hypertension and no PA. Young patients, who have higher chances of being cured long term, and high-risk patients, such as those with stage III or resistant hypertension, are those who will benefit most from an early diagnosis of PA. Therefore, the implementation of strategies to detect PA by a simplified diagnostic algorithm is necessary. In the patients who seek for surgical cure, adrenal vein sampling is key for the identification of unilateral PA and the achievement of optimal outcomes. Unfortunately, being technically demanding and poorly available, adrenal vein sampling represents the bottleneck in the workup of PA. Considering the novel knowledge generated in the past 5 years in many studies, particularly in the AVIS-2 study (Adrenal Vein Sampling International Study-2), based on 4 decades of experience at our center and on the last guidelines, we herein provide an update on the management of PA with recommendations for drug treatment and strategies to avoid adrenal vein sampling wherever it is poorly, or not, available.

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.

Decoding the role of aldosterone in glycation-induced diabetic complications

Diabetes-mediated development of micro and macro-vascular complications is a global concern. One of the factors is hyperglycemia induced the non-enzymatic formation of advanced glycation end products (AGEs). Accumulated AGEs bind with receptor of AGEs (RAGE) causing inflammation, oxidative stress and extracellular matrix proteins (ECM) modifications responsible for fibrosis, cell damage and tissue remodeling. Moreover, during hyperglycemia, aldosterone (Aldo) secretion increases, and its interaction with mineralocorticoid receptor (MR) through genomic and non-genomic pathways leads to inflammation and fibrosis. Extensive research on individual involvement of AGEs-RAGE and Aldo-MR pathways in the development of diabetic nephropathy (DN), cardiovascular diseases (CVDs), and impaired immune system has led to the discovery of therapeutic drugs. Despite mutual repercussions, the cross-talk between AGEs-RAGE and Aldo-MR pathways remains unresolved. Hence, this review focuses on the possible interaction of Aldo and glycation in DN and CVDs, considering the clinical significance of mutual molecular targets.

Current Landscape of Therapeutics for the Management of Hypertension - A Review

Hypertension is a critical health problem. It is also the primary reason for coronary heart disease, stroke, and renal vascular disease. The use of herbal drugs in the management of any disease is increasing. They are considered the best immune booster to fight against several types of diseases. To date, the demand for herbal drugs has been increasing because of their excellent properties. This review highlights antihypertensive drugs, polyphenols, and synbiotics for managing hypertension. Evidence is mounting in favour of more aggressive blood pressure control with reduced adverse effects, especially for specific patient populations. This review aimed to present contemporary viewpoints and novel treatment options, including cutting-edge technological applications and emerging interventional and pharmaceutical therapies, as well as key concerns arising from several years of research and epidemiological observations related to the management of hypertension.

Future treatments in hypertension: Can we meet the unmet needs of patients?

The prevalence of arterial hypertension is approximately 47% in the United States and 55% in Europe. Multiple different medical therapies are used to treat hypertension including diuretics, beta blockers, calcium channel blockers, angiotensin receptor blockers, angiotensin converting enzyme inhibitors, alpha blockers, central acting alpha receptor agonists, neprilysin inhibitors and vasodilators. However, despite the numerous number of medications, the prevalence of hypertension is on the rise, a considerable proportion of the hypertensive population is resistant to these therapeutic modalities and a definitive cure is not possible with the current treatment approaches. Therefore, there is a need for novel therapeutic strategies to provide better treatment and control of hypertension. In this review, our aim is to describe the latest developments in the treatment of hypertension including novel medication classes, gene therapies and RNA-based modalities.

Mineralocorticoid receptor antagonists in cardiovascular translational biology

This review examines the role of mineralocorticoid receptor antagonists (MRAs) in cardiovascular biology and the molecular mechanisms involved in mineralocorticoid receptor antagonism. The data discussed suggest that MRAs can play an important role in decreasing the impact of inflammation and fibrosis on cardiorenal outcomes. Evidence derived from major randomized clinical trials demonstrates that steroidal MRAs reduce mortality in patients with heart failure and reduced ejection fraction. Initial positive findings observed in patients with chronic kidney disease and type 2 diabetes (T2D) indicate the possible mechanisms of action of nonsteroidal MRAs, and the clinical benefits for patients with cardiorenal disease and T2D. This article supports the application of basic science concepts to expand our understanding of the molecular mechanisms of action involved in pathophysiology. This approach encourages the development of treatment options before diseases clinically manifest. Video Abstract: http://links.lww.com/CAEN/A42.

Novel 1,4-Dihydropyridine Derivatives as Mineralocorticoid Receptor Antagonists

The mineralocorticoid receptor (MR) belongs to the steroid receptor subfamily of nuclear receptors. MR is a transcription factor key in regulating blood pressure and mineral homeostasis. In addition, it plays an important role in a broad range of biological and pathological conditions, greatly expanding its interest as a pharmacological target. Non-steroidal MR antagonists (MRAs) are of particular interest to avoid side effects and achieve tissue-specific modulation of the receptor. The 1,4-dihydropyridine (1,4-DHP) ring has been identified as an appropriate scaffold to develop non-steroidal MRAs. We report the identification of a novel series of 1,4-DHP that has been guided by structure-based drug design, focusing on the less explored DHP position 2. Interestingly, substituents at this position might interfere with MR helix H12 disposition, which is essential for the recruitment of co-regulators. Several of the newly synthesized 1,4-DHPs show interesting properties as MRAs and have a good selectivity profile. These 1,4-DHPs promote MR nuclear translocation with less efficiency than the natural agonist aldosterone, which explains, at least in part, its antagonist character. Molecular dynamic studies are suggestive of several derivatives interfering with the disposition of H12 in the agonist-associated conformation, and thus, they might stabilize an MR conformation unable to recruit co-activators.

Clinical effect of nonsteroidal mineralocorticoid receptor (MR) antagonists in the treatment of diabetic kidney disease: expectations as a new therapeutic strategy

Diabetes mellitus is the main cause of chronic kidney disease (CKD) in Japan and worldwide. Although angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor blockers (ARBs) are basic drugs for the treatment of CKD with diabetes (diabetic kidney disease, DKD) with albuminuria and/or proteinuria, it has also become clear that the use of an ACE inhibitor or ARB alone is not fully sufficient. We have previously reported the clinical effects of mineralocorticoid receptor (MR) antagonists and recommended their use in addition to renin-angiotensin system inhibitors. Recently, new types of nonsteroidal MR antagonists have been developed, and the results of a large-scale study are expected. Nonsteroidal MR antagonists are distributed in the heart, lungs, liver, and kidneys when administered orally and are characterized by their equivalent distribution between the heart (nonepithelial tissue) and kidneys (epithelial tissue). We summarize the latest evidence regarding the use of nonsteroidal MR antagonists in the treatment of DKD. Hyperkalemia and renal dysfunction are frequent during MR antagonist treatment. However, with careful and combined monitoring of these two conditions, the effectiveness of MR antagonists will not be diminished; conversely, it is apparent that patients at such risk will benefit more from the addition of an MR antagonist to the treatment regimen. The most important measure against hyperkalemia is the regular monitoring of serum potassium levels and renal function. The safest and most reliable measure against hyperkalemia is the combined use of a new oral potassium adsorbent that has high potassium selectivity and few side effects. In DKD treatment, it is important to continue using MR antagonists without interruption as much as possible.

Intratracheally Inhalable Nifedipine-Loaded Chitosan-PLGA Nanocomposites as a Promising Nanoplatform for Lung Targeting: Snowballed Protection via Regulation of TGF-β/β-Catenin Pathway in Bleomycin-Induced Pulmonary Fibrosis

Pulmonary fibrosis is a serious ailment that may progress to lung remodeling and demolition, where the key participants in its incidence are fibroblasts responding to growth factors and cellular calcium swinging. Calcium channel blockers, like nifedipine (NFD), may represent auspicious agents in pulmonary fibrosis treatment. Unfortunately, NFD bears complicated pharmacodynamics and a diminished systemic bioavailability. Thus, the current study aimed to develop a novel, non-invasive nanoplatform for NFD for direct/effective pulmonary targeting via intratracheal instillation. A modified solvent emulsification–evaporation method was adopted for the fabrication of NFD-nanocomposites, integrating poly(D,L-lactide-co-glycolide) (PLGA), chitosan (CTS), and polyvinyl alcohol, and optimized for different physiochemical properties according to the 3² full factorial design. Additionally, the aerodynamic behavior of the nanocomposites was scrutinized through cascade impaction. Moreover, the pharmacokinetic investigations were conducted in rats. Furthermore, the optimum formulation was tested in bleomycin-induced pulmonary fibrosis in rats, wherein fibrotic and oxidative stress parameters were measured. The optimum nanocomposites disclosed a nanosized spherical morphology (226.46 nm), a high entrapment efficiency (61.81%) and a sustained release profile over 24 h (50.4%). As well, it displayed a boosted in vitro lung deposition performance with a mass median aerodynamic diameter of 1.12 µm. Pharmacokinetic studies manifested snowballed bioavailability of the optimal nanocomposites by 3.68- and 2.36-fold compared to both the oral and intratracheal suspensions, respectively. The intratracheal nanocomposites revealed a significant reduction in lung fibrotic and oxidative stress markers notably analogous to normal control besides repairing abnormality in TGF-β/β-catenin pathway. Our results conferred a compelling proof-of-principle that NFD-CTS-PLGA nanocomposites can function as a promising nanoparadigm for pulmonary fibrosis management.

Finerenone: First Approval

Finerenone (Kerendia^®), a first-in-class, orally administered, selective, nonsteroidal mineralocorticoid receptor antagonist (MRA), is being developed by Bayer HealthCare Pharmaceuticals for the treatment of diabetic kidney disease (DKD) and heart failure (HF), including chronic HF (CHF). Finerenone has been approved in the USA to reduce the risk of sustained estimated glomerular filtration rate (eGFR) decline, end stage renal disease (ESRD), cardiovascular death, nonfatal myocardial infarction (MI), and hospitalization for HF in adults with chronic kidney disease (CKD) associated with type 2 diabetes (T2D). Finerenone is undergoing regulatory assessment in the EU and in China. A phase III trial is investigating finerenone in patients who have HF with preserved ejection fraction. This article summarizes the milestones in the development of finerenone leading to this first approval to reduce the risk of serious kidney and heart complications in adults with CKD and T2D.

Differential effects of eplerenone versus amlodipine on muscle metaboreflex function in hypertensive humans

Numerous studies have demonstrated that sympathetic nervous system overactivation during exercise in hypertensive rodents and humans is due, in part, to an exaggerated reflex response known as the exercise pressor reflex. Our prior studies have implicated a key role of mineralocorticoid receptor activation in mediating an augmented exercise pressor reflex in spontaneously hypertensive rats, which is mitigated by blockade with eplerenone. However, the effect of eplerenone on exercise pressor reflex has not been assessed in human hypertension. Accordingly, the authors performed a randomized crossover study to compare the effects of eplerenone to another antihypertensive drug from a different class amlodipine on sympathetic nerve activity (SNA) in 14 patients with uncomplicated hypertension. The authors found that amlodipine unexpectedly augmented the increase in SNA during the second minute of isometric handgrip, which persisted into the post‐exercise circulatory arrest period (∆ SNA, from rest of 15 ± 2 vs. 9 ± 2 vs. 10 ± 2 bursts/min, amlodipine vs. baseline vs. eplerenone, respectively, p < .01), suggesting an exaggerated muscle metaboreflex function. Eplerenone did not alter sympathetic responses to exercise or post‐exercise circulatory arrest in the same hypertensive individuals. In conclusions, our studies provide the first direct evidence for a potentially unfavorable potentiation of muscle metaboreflex by amlodipine during isometric handgrip exercise in hypertensive patients whereas eplerenone has no significant effect. Our study may have clinical implications in terms of selection of antihypertensive agents that have the least detrimental effects on sympathetic neural responses to isometric exercise.

NP-59 Adrenal Scintigraphy as an Imaging Biomarker to Predict KCNJ5 Mutation in Primary Aldosteronism Patients

PURPOSE

Somatic KCNJ5 mutation occurs in half of unilateral primary aldosteronism (PA) and is associated with more severe phenotype. Mutation status can only be identified by tissue sample from adrenalectomy. NP-59 adrenal scintigraphy is a noninvasive functional study for disease activity assessment. This study aimed to evaluate the predictive value of NP-59 adrenal scintigraphy in somatic KCNJ5 mutation among PA patients who received adrenalectomy.

METHODS

Sixty-two PA patients who had NP-59 adrenal scintigraphy before adrenalectomy with available KCNJ5 mutation status were included. Two semiquantitative parameters, adrenal to liver ratio (ALR) and lesion to contralateral ratio of bilateral adrenal glands (CON) derived from NP-59 adrenal scintigraphy, of mutated and wild-type patients were compared. Cutoff values calculated by receiver-operating characteristic (ROC) analysis were used as a predictor of KCNJ5 mutation.

RESULTS

Twenty patients had KCNJ5 mutation and 42 patients were wild type. Patients harboring KCNJ5 mutation had both higher ALR and CON (p = 0.0031 and 0.0833, respectively) than wild-type patients. With ALR and CON cutoff of 2.10 and 1.95, the sensitivity and specificity to predict KCNJ5 mutation were 85%, 57% and 45%, 93%, respectively. Among 20 patients with KCNJ5 mutation, 16 showed G151R point mutation (KCNJ5- G151R) and 4 showed L168R point mutation (KCNJ5-L168R), which former one had significantly lower ALR (p=0.0471).

CONCLUSION

PA patients harboring somatic KCNJ5 mutation had significantly higher NP-59 uptake regarding to ALR and CON than those without mutation. APAs with KCNJ5-L168R point mutation showed significantly higher ALR than those with KCNJ5-G151R point mutation.

New drug targets for hypertension: A literature review

Hypertension is one of the most prevalent cardiovascular diseases worldwide. However, in the population of resistant hypertension, blood pressure is difficult to control effectively. Moreover, antihypertensive drugs may have adverse effect currently. Hence, new therapeutic targets and treatments are needed to uncovered and exploited to control hypertension and its comorbidities. In the past, classical drug targets, such as the aldosterone receptor, aldosterone synthase, and ACE2/angiotensin 1-7/Mas receptor axis, have been investigated. Recently, vaccines and drugs targeting the gastrointestinal microbiome, which represent drug classes, have also been investigated for the management of blood pressure. In this review, we summarized current knowledge on classical and new drug targets and discussed the potential utility of new drugs in the treatment of hypertension.

Felodipine in Treatment of Arterial Hypertension and Ischemic Heart Disease

Cardiovascular diseases are the leading cause of death both in the world and in the Russian Federation. The most significant contributors to the increase in mortality are arterial hypertension (AH) and ischemic heart disease (IHD). Dihydropyridine calcium channel blockers (CCBs) are the first line of treatment for these conditions. This is noted in the clinical guidelines for the diagnosis and treatment of AH and in the guidelines for the management of patients with chronic coronary syndromes. CCBs are a heterogeneous group of drugs that have both general and individual pharmacokinetic and pharmacodynamic properties. They are used in patients with AH and/or IHD, including those with concomitant diseases (diabetes mellitus, chronic kidney disease, bronchial asthma, chronic obstructive pulmonary disease, peripheral arterial disease). Felodipine is one of the CCBs. It has a combination of clinical effects, allowing the drug to be prescribed as a first-line therapy for AH, IHD and a combination of these diseases. This is noted in the registered indications for its use. This CCB has a sufficient evidence base of clinical trials demonstrating not only good antihypertensive and antianginal potential of the drug, but also the nephroprotection and cerebroprotection properties. The nephroprotective effect of felodipine is associated with a slowdown in the progression of chronic kidney disease, and the cerebroprotective effect is associated with a decrease in the risk of stroke and an improvement in cognitive functioning. The safety profile of felodipine is favorable: peripheral edema develops much less frequently. This is confirmed by the results of comparative studies. Felodipine is recommended for a wide range of patients with AH, IHD and their combination due to such clinical and pharmacological properties.

Primary Aldosteronism: JACC State-of-the-Art Review

Primary aldosteronism (PA) is a common, but frequently overlooked, cause of arterial hypertension and excess cardiovascular events, particularly atrial fibrillation. As timely diagnosis and treatment can provide a cure of hyperaldosteronism and hypertension, even when the latter is resistant to drug treatment, strategies to screen patients for PA early with a simplified diagnostic algorithm are justified. They can be particularly beneficial in some subgroups of hypertensive patients, as those who are at highest cardiovascular risk. However, identification of the surgically curable cases of PA and achievement of optimal results require subtyping with adrenal vein sampling, which, as it is technically challenging and currently performed only in tertiary referral centers, represents the bottleneck in the work-up of PA. Measures aimed at improving the clinical use of adrenal vein sampling and at developing alternative techniques for subtyping, alongside recommendations for drug treatment, including new development in the field, and for follow-up are discussed.

Mineralocorticoid Receptor Blockers: Novel Selective Nonsteroidal Mineralocorticoid Receptor Antagonists

PURPOSE OF REVIEW

Recently, nonsteroidal mineralocorticoid receptor (MR) antagonists (MRAs), which have been proposed to be called MR blockers (MRBs), have become available for clinical use, but their clinical role is unknown. We reviewed the clinical roles of MRAs and MRBs based on previous knowledge and as demonstrated in representative clinical trials.

RECENT FINDINGS

Steroidal MRAs, such as spironolactone and eplerenone, inhibit the action of aldosterone and cortisol in MRs expressed in several organs and cell types, and accumulating clinical studies have revealed that they exert hypotensive and cardiorenal protective effects. Recently, MRBs, including finerenone and esaxerenone, have been developed and are expected to lower the risk of hyperkalemia, which is common when steroidal MRAs are used. Although the differences between MRAs and MRBs in clinical practice have not yet been established, further studies in this field are expected to broaden our understanding. MRBs exert antihypertensive and cardiorenal protective effects, and their potency is thought to be far superior to that of MRAs, because MRBs have both strong MR inhibitory action and high selectivity. Thus, MRBs could be a promising agent for the treatment of hypertension and cardiorenal, cerebral, and metabolic disorders.

The expanding class of mineralocorticoid receptor modulators: New ligands for kidney, cardiac, vascular, systemic and behavioral selective actions

This paper reviews the class of mineralocorticoid receptor (MR) modulators, especially new nonsteroidal antagonists. MR is a nuclear receptor expressed in many tissues and cell types. Aldosterone, the most important mineralocorticoid hormone and MR agonist, has many unfavorable effects, especially on the heart, blood vessels, and kidneys, by promoting fibrosis and tissue remodelling. Classical synthetic MR antagonists (spironolactone, eplerenone) have proven useful in clinical practice through their antihypertensive effects in resistant forms, and through benefits on morbidity and mortality in heart failure with reduced ejection fraction. These benefits are associated with important side effects, hyperkalemia being the main limitation. In the latest years, a new generation of MR modulators with a nonsteroidal structure has emerged. These compounds are more selective than classical MR antagonists, with much higher affinity for the MR than for the glucocorticoid, androgen, or progesterone receptors. Recent clinical and experimental observations suggest that nonsteroidal MR antagonists, especially finerenone, have proven superior renoprotective properties, antiproteinuric efficacy, inhibition of inflammation and heart fibrosis in animal models, without sharing the side effects of steroidal MR antagonists. Nonsteroidal MR modulators represent an interesting new therapeutic approach for the prevention and progression of chronic kidney disease and for patients with heart failure and renal disease. Despite these promising data, there are still many issues to be clarified and it is necessary to accumulate solid evidence from studies on larger numbers of patients and from head-to-head clinical trials.

Epidermal growth factor receptor/extracellular signal-regulated kinase pathway enhances mineralocorticoid receptor transcriptional activity through protein stabilization

Activation of mineralocorticoid receptor (MR) is evoked by aldosterone, and it induces hypertension and cardiovascular disease when it's concomitant with excessive salt loading. We have proposed the notion of "MR-associated hypertension", in which add-on therapy of MR blockers is effective even though serum aldosterone level is within normal range. To elucidate its underlying molecular mechanism, we focused on the effect of epidermal growth factor receptor (EGFR)/extracellular signal-regulated kinase (ERK) activation on MR activity. Epidermal growth factor (EGF) administration increased MR transcriptional activity through EGFR/ERK pathway and increased protein level by counteracting MR ubiquitylation in vitro. EGF administration in vivo also increased MR protein level and target gene expression in kidney, which were decreased by EGFR inhibitor. In addition, the administration of EGFR inhibitor lowered systolic blood pressure and MR activity in DOCA/salt-treated mice. In conclusion, EGFR/ERK pathway activation is considered as one of the underlying mechanisms of aberrant MR activation and EGFR/ERK pathway blockade could be an alternative approach for the prevention of MR-related cardiovascular events.

Calcium Ion Channels: Roles in Infection and Sepsis Mechanisms of Calcium Channel Blocker Benefits in Immunocompromised Patients at Risk for Infection

Immunosuppression may occur for a number of reasons related to an individual's frailty, debility, disease or from therapeutic iatrogenic intervention or misadventure. A large percentage of morbidity and mortality in immunodeficient populations is related to an inadequate response to infectious agents with slow response to antibiotics, enhancements of antibiotic resistance in populations, and markedly increased prevalence of acute inflammatory response, septic and infection related death. Given known relationships between intracellular calcium ion concentrations and cytotoxicity and cellular death, we looked at currently available data linking blockade of calcium ion channels and potential decrease in expression of sepsis among immunosuppressed patients. Notable are relationships between calcium, calcium channel, vitamin D mechanisms associated with sepsis and demonstration of antibiotic-resistant pathogens that may utilize channels sensitive to calcium channel blocker. We note that sepsis shock syndrome represents loss of regulation of inflammatory response to infection and that vitamin D, parathyroid hormone, fibroblast growth factor, and klotho interact with sepsis defense mechanisms in which movement of calcium and phosphorus are part of the process. Given these observations we consider that further investigation of the effect of relatively inexpensive calcium channel blockade agents of infections in immunosuppressed populations might be worthwhile.

Identification of Morpholino-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-ones as Nonsteroidal Mineralocorticoid Antagonists

A novel series of morpholine-based nonsteroidal mineralocorticoid receptor antagonists is reported. Starting from a pyrrolidine HTS hit 9 that possessed modest potency but excellect selectivity versus related nuclear hormone receptors, a series of libraries led to identification of morpholine lead 10. After further optimization, cis disubstituted morpholine 22 was discovered, which showed a 45-fold boost in binding affinity and corresponding functional potency compared to 13. While 22 had high clearance in rat, it provided sufficient exposure at high doses to favorably assess in vivo efficacy (increased urinary Na⁺/K⁺ ratio) and safety. In contrast to rat, the dog and human MetID and PK profiles of 22 were adequate, suggesting that it could be suitable as a potential clinical asset.

A comprehensive review of an unmet public health issue: resistant hypertension

Resistant hypertension is an intractable problem to patients and physicians. In recent decades, a substantial amount of basic and epidemiological studies provide us a vast number of valuable evidence and information about this once elusive disease. Better understanding about this entity could help physicians improve diagnostic and therapeutic accuracy. In present review, therefore, we first will detail the definition and diagnosis of resistant hypertension between cardiology societies, and followed by the information of prevalence of resistant hypertension around the world, and then briefly discuss currently used different nomenclature of resistant hypertension, and finally present diagnostic and therapeutic strategies of resistant hypertension.

Clinical roles of calcium channel blockers in ischemic heart diseases

Calcium (Ca) channel blockers (CCBs) inhibit Ca²⁺ channels in the myocardium or vascular smooth muscle cells, inhibit myocardium contraction, inhibit the impulse conduction system (anti-arrhythmias) and cause vasodilation. New classifications based on subtypes of Ca channels and α1 subunits have been proposed. Moreover, CCBs have pleiotropic effects on coronary spastic angina (CSA), including variant angina, myocardial infarction (MI) and stent thrombosis (ST). Although the roles of CCBs in clinical situations remain unknown, further studies in this field are expected to broaden our understanding. In this article, we explain the clinical roles of CCBs in ischemic heart diseases, such as CSA, MI and ST, based on previous knowledge and as demonstrated in representative clinical trials.

Steroidal and Novel Non-steroidal Mineralocorticoid Receptor Antagonists in Heart Failure and Cardiorenal Diseases: Comparison at Bench and Bedside

Characterization of mice with cell-specific deletion or overexpression of the mineralocorticoid receptor (MR) shed a new light on its role in health and disease. Pathophysiological MR activation contributes to a plethora of deleterious molecular mechanisms in the development of cardiorenal diseases like chronic kidney disease (CKD) and heart failure (HF). Accordingly, the available steroidal MR antagonists (MRAs) spironolactone (first generation MRA) and eplerenone (second generation MRA) have been shown to be effective in reducing cardiovascular (CV) mortality and morbidity in patients with chronic HF and a reduced left ventricular ejection fraction (HFrEF). However, they remain underutilized, in large part owing to the risk inducing severe adverse events including hyperkalemia and worsening of kidney function, particularly when given on top of inhibitors of the renin angiotensin system (RAS) to patients with concomitant kidney dysfunction. Novel, potent, and selective non-steroidal MRAs (third generation) were identified in drug discovery campaigns and a few entered clinical development recently. One of these is finerenone with different physicochemical, pharmacokinetics, and pharmacological properties in comparison with the steroidal MRAs. Available data from five clinical phase II trials with finerenone in more than 2,000 patients with HF and additional CKD and/or diabetes as well as in patients with diabetic kidney disease demonstrated that neither hyperkalemia nor reductions in kidney function were limiting factors to its use. Moreover, finerenone demonstrated a nominally improved outcome compared to eplerenone in a phase IIb trial with 1,066 patients with HFrEF and concomitant type 2 diabetes mellitus (T2DM) and/or CKD.

A small molecule screening to detect potential therapeutic targets in human podocytes

WIDMEIER E, TAN W, AIRIK M, HILDEBRANDT F

A small molecule screening to detect potential therapeutic targets in human podocytes. Am J Physiol Renal Physiol 312: F157-F171, 2017. First published October 19, 2016; doi:10.1152/ajprenal.00386.2016. Steroid-resistant nephrotic syndrome (SRNS) inevitably progresses to end-stage kidney disease, requiring dialysis or transplantation for survival. However, treatment modalities and drug discovery remain limited. Mutations in over 30 genes have been discovered as monogenic causes of SRNS. Most of these genes are predominantly expressed in the glomerular epithelial cell, the podocyte, placing it at the center of the pathogenesis of SRNS. Podocyte migration rate (PMR) represents a relevant intermediate phenotype of disease in monogenic causes of SRNS. We therefore adapted PMR in a high-throughput manner to screen small molecules as potential therapeutic targets for SRNS. We performed a high-throughput drug screening of a National Institutes of Health Clinical Collection (NCC) library (n = 725 compounds) measuring PMR by videomicroscopy. We used the Woundmaker to perform individual 96-well scratch wounds and screened compounds using a quantitative kinetic live cell imaging migration assay using IncuCyte ZOOM technology. Using a normal distribution for the average PMR in wild-type podocytes with a vehicle control (DMSO), we applied a 90% confidence interval to define "distinct" compounds (5% faster/slower PMR) and found that 12 of 725 compounds (at 10 μM) reduced PMR. Clusters of drugs that alter PMR included actin/tubulin modulators such as the azole class of antifungals and antineoplastic vinca-alkaloids. We hereby identify compounds that alter PMR. The PMR assay provides a new avenue to test therapeutics for nephrotic syndrome. Positive results may reveal novel pathways in the study of glomerular diseases such as SRNS.

Third-generation Mineralocorticoid Receptor Antagonists: Why Do We Need a Fourth?

The first mineralocorticoid receptor (MR) antagonist, spironolactone, was developed almost 60 years ago to treat primary aldosteronism and pathological edema. Its use waned in part because of its lack of selectivity. Subsequently, knowledge of the scope of MR function was expanded along with clinical evidence of the therapeutic importance of MR antagonists to prevent the ravages of inappropriate MR activation. Forty-two years elapsed between the first and MR-selective second generation of MR antagonists. Fifteen years later, despite serious shortcomings of the existing antagonists, a third-generation antagonist has yet to be marketed. Progress has been slowed by the lack of appreciation of the large variety of cell types that express the MR and its diverse cell-type-specific actions, and also its unique complex interaction actions at the molecular level. New MR antagonists should preferentially target the inflammatory and fibrotic effects of MR and perhaps its excitatory effects on sympathetic nervous system, but not the renal tubular epithelium or neurons of the cortex and hippocampus. This review briefly describes efforts to develop a third-generation MR antagonist and why fourth generation antagonists and selective agonists based on structural determinants of tissue and ligand-specific MR activation should be contemplated.

SFE/SFHTA/AFCE consensus on primary aldosteronism, part 7: Medical treatment of primary aldosteronism

Spironolactone, which is a potent mineralocorticoid receptor antagonist, represents the first line medical treatment of primary aldosteronism (PA). As spironolactone is also an antagonist of the androgen and progesterone receptor, it may present side effects, especially in male patients. In case of intolerance to spironolactone, amiloride may be used to control hypokaliemia and we suggest that eplerenone, which is a more selective but less powerful antagonist of the mineralocorticoid receptor, be used in case of intolerance to spironolactone and insufficient control of hypertension by amiloride. Specific calcic inhibitors and thiazide diuretics may be used as second or third line therapy. Medical treatment of bilateral forms of PA seem to be as efficient as surgical treatment of lateralized PA for the control of hypertension and the prevention of cardiovascular and renal morbidities. This allows to propose medical treatment of PA to patients with lateralized forms of PA who refuse surgery or to patients with PA who do not want to be explored by adrenal venous sampling to determine whether they have a bilateral or lateralized form.

Mineralocorticoid receptor antagonists-pharmacodynamics and pharmacokinetic differences

Mineralocorticoid receptor antagonists (MRAs) are best known as potassium-sparing diuretics due to their blockade of aldosterone action in renal epithelial tissues. They are also beneficial for the treatment of heart failure, primarily due to effects in non-epithelial tissues. Currently there are only two steroidal MRAs that have been approved for use; spironolactone (and its active metabolite canrenone) and eplerenone. However, the search is on for novel generations of MRAs with increased potency and tissue selectivity. A number of novel non-steroidal compounds are in preclinical and early development, with one agent moving to phase III trials. The development of these agents and the mechanisms for their pharmacologic superiority compared to earlier generations of MRAs will be discussed in this review.

Mineralocorticoid Receptor Antagonists and Clinical Outcomes in Primary Aldosteronism: As Good as Surgery?

Primary aldosteronism (PA) is detected with increasing frequency in hypertensive patients and is associated with excess cardiovascular, renal, and metabolic complications. For these reasons, appropriate choices for treatment of this endocrine condition are mandatory. Adrenalectomy is safely performed in PA patients when adrenal venous sampling (AVS) demonstrates lateralized aldosterone secretion. AVS, however, is a complex procedure and even among worldwide referral centers there are substantial discrepancies for interpretation of results. Also, in the majority of PA patients with lateralized aldosterone secretion, hypertension may persist after adrenalectomy requiring use of additional antihypertensive agents. Treatment with mineralocorticoid receptor antagonists (MRAs) is currently recommended for PA patients with bilateral adrenal disease, but these agents effectively decrease blood pressure also in patients with unilateral disease, although concern remains for possible sex-related side effects. Prospective studies indicate that MRAs have therapeutic values comparable to surgery in the long-term, inasmuch as they effectively correct metabolic abnormalities and subclinical organ damage and reduce the risk of cardiovascular events and renal disease progression. This article overviews the clinical outcomes obtained in patients with PA with use of MRAs.

Drug therapy of apparent treatment-resistant hypertension: focus on mineralocorticoid receptor antagonists

Apparent treatment-resistant hypertension (aTRH) is defined as blood pressure (BP) >140/90 mmHg despite three different antihypertensive drugs including a diuretic. aTRH is associated with an increased risk of cardiovascular events, including stroke, chronic renal failure, myocardial infarction, congestive heart failure, aortic aneurysm, atrial fibrillation, and sudden death. Preliminary studies of renal nerve ablation as a therapy to control aTRH were encouraging. However, these results were not confirmed by the Symplicity 3 trial. Therefore, attention has refocused on drug therapy. Secondary forms of hypertension and associated conditions such as obesity, sleep apnea, and primary aldosteronism are common in patients with aTRH. The pivotal role of aldosterone in the pathogenesis of aTRH in many cases is well recognized. For patients with aTRH, the Joint National Committee-8, the European Society of Hypertension, and a recent consensus conference recommend that a diuretic, ACE inhibitor, or angiotensin receptor blocker and calcium channel blocker combination be used to maximally tolerated doses before starting a 'fourth-line' drug such as a mineralocorticoid receptor (MR) antagonist. Although the best fourth-line drug for aTRH has not been extensively investigated, a number of studies summarized here show that an MR antagonist is effective in reducing BP when added to the standard multi-drug regimen.

Management of hypertension and heart failure in patients with Addison's disease

Addison's disease may be complicated by hypertension and less commonly by heart failure. We review the pathophysiology of the renin-angiotensin-aldosterone axis in Addison's disease and how this is altered in the setting of hypertension and heart failure. An essential first step in management in both conditions is optimizing glucocorticoid replacement and considering dose reduction if excessive. Following this, if a patient with Addison's disease remains hypertensive, the fludrocortisone dose should be reviewed and reduced if there are clinical and/or biochemical signs of mineralocorticoid excess. In the absence of such signs, where the renin is towards the upper end of the normal range or elevated, an angiotensin II (AII) receptor antagonist or angiotensin converting enzyme (ACE) inhibitor is the treatment of choice, and the fludrocortisone dose should remain unchanged. Dihydropyridine calcium channel blockers are clinically useful as second line agents, but diuretics should be avoided. In the setting of heart failure, there is an increase in total body sodium and water; therefore, it is appropriate to reduce and rarely consider ceasing the fludrocortisone. Loop diuretics may be used, but not aldosterone antagonists such as spironolactone or eplerenone. Standard treatment with ACE inhibitors, or as an alternative, AII receptor antagonists, are appropriate. Measurements of renin are no longer helpful in heart failure to determine the volume status but plasma levels of brain natriuretic peptide (BNP/proBNP) may help guide therapy.

Outcomes of drug-based and surgical treatments for primary aldosteronism

Treatments for primary aldosteronism (PA) aim to correct or prevent the deleterious consequences of hyperaldosteronism: hypertension, hypokalemia, and direct target organ damage. Patients with unilateral PA considered fit for surgery can undergo laparoscopic adrenalectomy, which significantly decreases blood pressure (BP) and medications in most cases and cures hypertension in about 40%. Mineralocorticoid receptor antagonists (MRA) are used to treat patients with bilateral PA and those with unilateral PA if surgery is not possible or not desired. Spironolactone is more potent than eplerenone, but high doses are poorly tolerated in men. MRA can be replaced or complemented with epithelial sodium channel blockers, such as amiloride. Thiazide diuretics and calcium channel blockers are used when the first-line drugs are insufficient to control BP. Dietary sodium restriction should be implemented in all cases because the deleterious consequences of hyperaldosteronism are dependent on salt loading. Several studies comparing the results of surgery and MRA have reported no differences in terms of BP, serum potassium concentration, or cardiovascular and kidney outcomes, although the benefits of treatment tend to be observed sooner with surgery. Patients with PA display relative glomerular hyperfiltration, which is reversed by specific treatment, revealing CKD in 30% of patients. However, further kidney damage is lessened by the treatment of PA.

Is there a new dawn for selective mineralocorticoid receptor antagonism?

PURPOSE OF REVIEW

Aldosterone and the mineralocorticoid receptor contribute to resistant hypertension and cardiovascular mortality, and mineralocorticoid receptor antagonists effectively reduce these complications. Their use is limited in certain populations with a higher risk of hyperkalemia or renal dysfunction. This review will highlight recent developments in extra-renal mineralocorticoid receptor research and the development of novel mineralocorticoid receptor antagonists.

RECENT FINDINGS

Tissue-specific knockout-out models provide definitive evidence that the vascular mineralocorticoid receptor directly contributes to hypertension and vascular remodeling, independent of renal effects. Several nonsteroidal mineralocorticoid receptor antagonists are in preclinical development or early-stage clinical trials. Several nonsteroidal mineralocorticoid receptor antagonists have demonstrated preserved cardiovascular benefit with a reduced incidence of hyperkalemia in preclinical studies.

SUMMARY

Novel, potent nonsteroidal mineralocorticoid receptor antagonists are in development, although their effect on cardiovascular and adverse drug events requires further investigation.

New Approaches in the Treatment of Hypertension

Hypertension is the most common modifiable risk factor for cardiovascular disease and death, and lowering blood pressure with antihypertensive drugs reduces target organ damage and prevents cardiovascular disease outcomes. Despite a plethora of available treatment options, a substantial portion of the hypertensive population has uncontrolled blood pressure. The unmet need of controlling blood pressure in this population may be addressed, in part, by developing new drugs and devices/procedures to treat hypertension and its comorbidities. In this Compendium Review, we discuss new drugs and interventional treatments that are undergoing preclinical or clinical testing for hypertension treatment. New drug classes, eg, inhibitors of vasopeptidases, aldosterone synthase and soluble epoxide hydrolase, agonists of natriuretic peptide A and vasoactive intestinal peptide receptor 2, and a novel mineralocorticoid receptor antagonist are in phase II/III of development, while inhibitors of aminopeptidase A, dopamine β-hydroxylase, and the intestinal Na + /H + exchanger 3, agonists of components of the angiotensin-converting enzyme 2/angiotensin(1–7)/Mas receptor axis and vaccines directed toward angiotensin II and its type 1 receptor are in phase I or preclinical development. The two main interventional approaches, transcatheter renal denervation and baroreflex activation therapy, are used in clinical practice for severe treatment resistant hypertension in some countries. Renal denervation is also being evaluated for treatment of various comorbidities, eg, chronic heart failure, cardiac arrhythmias and chronic renal failure. Novel interventional approaches in early development include carotid body ablation and arteriovenous fistula placement. Importantly, none of these novel drug or device treatments has been shown to prevent cardiovascular disease outcomes or death in hypertensive patients.

[New therapy concepts for heart failure with preserved ejection fraction]

The management of patients with heart failure and preserved ejection fraction (HFpEF) remains challenging and requires an accurate diagnosis. Although currently no convincing therapy that can prolong survival in patients with HFpEF has been established, treatment of fluid retention, heart rate and control of comorbidities are important cornerstones to improve the quality of life and symptoms. In recent years many new therapy targets have been tested for development of successful interventional strategies for HFpEF. Insights into new mechanisms of HFpEF have shown that heart failure is associated with dysregulation of the nitric oxide-cyclic guanosine monophosphate-protein kinase (NO-cGMP-PK) pathway. Two new drugs are currently under investigation to test whether this pathway can be significantly improved by either the neprilysin inhibitor LCZ 696 due to an increase in natriuretic peptides or by the soluble guanylate cyclase stimulator vericiguat, which is also able to increase cGMP. In addition, several preclinical or early phase studies which are currently investigating new mechanisms for matrix, intracellular calcium and energy regulation including the role of microRNAs and new devices are presented and discussed.

Beneficial effects of proanthocyanidins in the cardiac alterations induced by aldosterone in rat heart through mineralocorticoid receptor blockade

Aldosterone administration in rats results in several cardiac alterations. Previous studies have demonstrated that proanthocyanidins, phenolic bioactive compounds, have cardioprotective effects. We studied the potential beneficial effects of the proanthocyanidin-rich almond skin extract (PASE) on the cardiac alterations induced by aldosterone-salt treatment, their effects in mineralocorticoid receptor activity and we sought to confirm proanthocyanidins as the specific component of the extract involved in the beneficial cardiac effects. Male Wistar rats received aldosterone (1 mg/Kg/day) +1% NaCl for 3 weeks. Half of the animals in each group were simultaneously treated with either PASE (100 mg/Kg/day) or spironolactone (200 mg/Kg/day). The ability of PASE to act as an antagonist of the mineralocorticoid receptor was examined using a transactivation assay. High performance liquid chromatography was used to identify and to isolate proanthocyanidins. Hypertension and diastolic dysfunction induced by aldosterone were abolished by treatment with PASE. Expression of the aldosterone mediator SGK-1, together with fibrotic, inflammatory and oxidative mediators were increased by aldosterone-salt treatment; these were reduced by PASE. Aldosterone-salt induced transcriptional activity of the mineralocorticoid receptor was reduced by PASE. HPLC confirmed proanthocyanidins as the compound responsible for the beneficial effects of PASE. The effects of PASE were comparable to those seen with the mineralocorticoid antagonist, spironolactone. The observed responses in the aldosterone-salt treated rats together with the antagonism of transactivation at the mineralocorticoid receptor by PASE provides evidence that the beneficial effect of this proanthocyanidin-rich almond skin extract is via as a mineralocorticoid receptor antagonist with proanthocyanidins identified as the compounds responsible for the beneficial effects of PASE.

Interfering with mineralocorticoid receptor activation: the past, present, and future

Aldosterone is a potent mineralocorticoid produced by the adrenal gland. Aldosterone binds to and activates the mineralocorticoid receptor (MR) in a plethora of tissues, but the cardiovascular actions of aldosterone are of primary interest clinically. Although MR antagonists were developed as antihypertensive agents, they are now considered to be important therapeutic options for patients with heart failure. Specifically, blocking only the MR has proven to be a difficult task because of its similarity to other steroid receptors, including the androgen and progesterone receptors. This lack of specificity caused the use of the first-generation mineralocorticoid receptor antagonists to be fraught with difficulty because of the side effects produced by drug administration. However, in recent years, several advances have been made that could potentially increase the clinical use of agents that inhibit the actions of aldosterone. These will be discussed here along with some examples of the beneficial effects of these new therapeutic agents.

Are there any new pharmacologic therapies on the horizon to better treat hypertension? A state-of-the-art paper

Hypertension is the most important cardiovascular risk factor. We have witnessed a significant improvement in hypertension treatment and control and an impressive growth in the pharmacologic options available to clinicians and hypertension specialists. With up to a third of patients with hypertension not at the recommended goal blood pressures, it is critically important to develop novel therapeutic approaches to better treat hypertension. This review will explore the ever-expanding horizon of antihypertensive treatment and will focus on 2 major areas of drug development. First, we will review novel targets for pharmacologic treatment and novel molecules and classes of drugs in various phases of development and recognize the limitations we face in their transition from research and development to clinical practice. Then, we will discuss an expanding array of combination strategies to better treat hypertension with the goal of minimizing the burden of cardiovascular and renal complications of hypertension.