Mineralocorticoid receptor blockade reverses obesity-related changes in expression of adiponectin, peroxisome proliferator-activated receptor-gamma, and proinflammatory adipokines

Understanding the Role of Adipokines in Cardiometabolic Dysfunction: A Review of Current Knowledge

Cardiometabolic risk and associated dysfunctions contribute largely to the recent rise in mortality globally. Advancements in multi-omics in recent years promise a better understanding of potential biomarkers that enable an early diagnosis of cardiometabolic dysfunction. However, the molecular mechanisms driving the onset and progression of cardiometabolic disorders remain poorly understood. Adipokines are adipocyte-specific cytokines that are central to deleterious cardiometabolic alterations. They exhibit both pro-inflammatory and anti-inflammatory effects, complicating their association with cardiometabolic disturbances. Thus, understanding the cardiometabolic association of adipokines from a molecular and signaling perspective assumes great importance. This review presents a comprehensive outline of the most prominent adipokines exhibiting pro-inflammatory and/or anti-inflammatory functions in cardiometabolic dysfunction. The review also presents an insight into the pathophysiological implications of such adipokines in different cardiometabolic dysfunction conditions, the status of adipokine druggability, and future studies that can be undertaken to address the existing scientific gap. A clear understanding of the functional and mechanistic role of adipokines can potentially improve our understanding of cardiovascular disease pathophysiology and enhance our current therapeutic regimen in the years to come.

MicroRNA-24-3p targeting Top1 in perirenal fat is involved in circulating inflammation and high cardiovascular disease risk in patients with primary aldosteronism

CONTEXT

Patients with primary aldosteronism (PA) are at a high risk of cardiovascular diseases (CVD) and metabolic syndrome. Notable inflammatory and fibrotic changes and differential microRNA (miRNA) expression profiles in the perirenal fat observed in PA may contribute to this increased risk, however, which has not been fully elucidated.

OBJECTIVE

This study aimed to explore the role of high expression of miR-24-3p in perirenal fat in circulating inflammation and its correlation with a high risk of CVD in patients with PA.

METHODS

Perirenal fat thickness (PRFT) measured by computed tomography (CT), miR-24-3p expression in perirenal fat, circulating inflammatory factors from adrenal veins and peripheral blood in patients with PA were analyzed. In vitro, white and brown adipocytes with miR-24-3p overexpression or inhibition respectively were stimulated with aldosterone and a unidirectional co-culture model of adipocytes and HUVEC was established. The target genes of miR-24-3p were identified.

RESULTS

Patients with PA and CVD have significantly higher PRFT than those without CVD. The expression level of miR-24-3p in perirenal fat was significantly positively correlated with PRFT. MiR-24-3p was significantly upregulated in the perirenal fat of PA and was associated with increased adipogenesis, inflammation, and oxidative stress, correlating with plasma aldosterone concentration (PAC), PRFT, cardiac remodeling, and weight gain. The IL-6 level in the peripheral blood was elevated in patients with PA and CVD, and the affected adrenal vein had the highest IL-6 level. Targeting Top1, miR-24-3p modulated aldosterone-induced effects in adipocytes and influenced IL-6 secretion, thereby affecting HUVEC.

CONCLUSION

The upregulation of miR-24-3p in the perirenal fat induced inflammation and oxidative stress by targeting Top1, which may contribute to a high risk of CVD in patients with PA.

The renin-angiotensin-aldosterone system and salt sensitivity of blood pressure offer new insights in obesity phenotypes

OBJECTIVE

Individuals who have metabolically healthy overweight/obesity (MHOO) do not have cardiometabolic complications despite an elevated BMI. Renin-angiotensin-aldosterone system (RAAS) activation and salt sensitivity of blood pressure (SSBP) are cardiovascular disease (CVD) risks, which are increased in individuals with higher BMI values. Little is known about the differences in RAAS activation and SSBP between MHOO and metabolically unhealthy overweight/obesity (MUOO) phenotypes.

METHODS

We studied 1430 adults on controlled dietary sodium. Individuals in the MHOO group had BMI ≥ 25 kg/m2 without comorbidities (e.g., diabetes, dyslipidemia, hypertension, CVD), whereas individuals in the MUOO group had BMI ≥ 25 kg/m2 and at least one comorbidity. The control group included healthy individuals (BMI 18.5-24.9 kg/m2).

RESULTS

BMI was similar between the MHOO (28.9 kg/m2) and MUOO groups (29.3 kg/m2; p = 0.317). On liberal sodium, the MUOO group had activated RAAS compared with the MHOO group, including higher plasma aldosterone concentration (mean [SD], 1.11 [0.48] ng/dL; p = 0.020), plasma angiotensin II levels (4.11 [2.0] pg/mL; p = 0.040), and percentage of individuals with plasma renin activity ≥ 1.0 ng/mL/h (+3.6%; p = 0.017). The MUOO group had higher SSBP than the MHOO group (6.0 [1.9] mm Hg; p = 0.002). Applying a zero-to-six-point metabolic health score found that a worse score was associated with higher measurements of RAAS activity and SSBP (p < 0.001).

CONCLUSIONS

Compared to the MHOO group, the MUOO group was characterized by an increase in the following two CVD risk factors: higher RAAS activity and SSBP on controlled sodium diets. Therapeutic interventions targeting the effects of angiotensin II and/or aldosterone may offer cardiometabolic protection for individuals with the MUOO phenotype.

Serum Cortisol and Cardiovascular Disease Risk - A Potential Biomarker

Cardiovascular disease (CVD), the leading cause of death globally, poses a significant burden on the healthcare sector. Its association with stress and Cushing's Syndrome has driven cortisol, the 'stress hormone,' to be a potential candidate in determining CVD risk. Cortisol synthesis and release through the hypothalamic-pituitary-adrenal (HPA) axis are regulated by several hormones and receptors involved in the pathological cascade towards CVD. Evidence suggests that metabolic syndrome plays a major role in cortisol-mediated CVD risk. On the other hand, non-metabolic features are also implicated when the association between cortisol and CVD risk remains significant upon normalisation of metabolic parameters. Correspondingly, the treatment for hypercortisolism is often found effective in lowering CVD risk. Despite available evidence, several factors continue to hinder the clinical use of cortisol as a risk biomarker for CVD. This review provides an insight into the role of serum cortisol in CVD progression and risk, with emphasis on the mechanistic features and parameters.

Mineralocorticoid receptor activates postnatal adiposity in zebrafish lacking proopiomelanocortin

The proopiomelanocortin (Pomc)-derived peptides, including adrenocorticotropic hormone and α-melanocyte stimulating hormone (α-Msh), play both a central and a peripheral role in modulating the stress response. The central role is predominantly associated with nutrient homeostasis, while peripherally they play an important role in the synthesis of glucocorticoids (GCs) in response to stress. Pomc mutations are a major risk factor in the development of early-onset childhood obesity in humans. This is attributed primarily to their central effects on melanocortin receptor dysfunction leading to hyperphagia and reduced energy expenditure, while the peripheral mechanism contributing to obesity has largely been unexplored. Here, we tested the hypothesis that Pomc mutation-mediated adrenal insufficiency and the associated changes in GC signaling contribute to postnatal adiposity using zebrafish as a model. We generated a ubiquitous Pomc knockout zebrafish that mimicked the mammalian mutant phenotype of adrenal insufficiency and enhanced adiposity. The loss of Pomc inhibited stress-induced cortisol production and reprogrammed GC signaling by reducing glucocorticoid receptor responsiveness, whereas the mineralocorticoid receptor (Mr) signaling was enhanced. Larval feeding led to enhanced growth and adipogenesis in the Pomc mutants, and this was inhibited by eplerenone, an Mr antagonist. Altogether, our results underscore a key role for Mr signaling in early developmental adipogenesis and a possible target for therapeutic intervention for early-onset childhood obesity due to Pomc dysfunction.

The effects of antihypertensive drugs on glucose metabolism

Abnormal glucose metabolism is a common disease of the endocrine system. The effects of drugs on glucose metabolism have been reported frequently in recent years, and since abnormal glucose metabolism increases the risk of microvascular and macrovascular complications, metabolic disorders, and infection, clinicians need to pay close attention to these effects. A variety of common drugs can affect glucose metabolism and have different mechanisms of action. Hypertension is a common chronic cardiovascular disease that requires long-term medication. Studies have shown that various antihypertensive drugs also have an impact on glucose metabolism. Among them, α-receptor blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and calcium channel blockers can improve insulin resistance, while β-receptor blockers, thiazides and loop diuretics can impair glucose metabolism. The aim of this review was to discuss the mechanisms underlying the effects of various antihypertensive drugs on glucose metabolism in order to provide reference information for rational clinical drug use.

Two-Pronged Attack: Dual Activation of Fat Reduction Using Near-Infrared-Responsive Nanosandwich for Targeted Anti-Obesity Treatment

Excessive fat accumulation and chronic inflammation are two typical characteristics of obesity. AMP-activated protein kinase (AMPK), a master regulator of energy metabolism, is involved in adipogenesis, lipogenesis, and inflammation modulation in adipose tissue (AT). Thus, effective lipid reduction and anti-inflammation through AMPK regulation play vital roles in treating obesity. Herein, an anti-obesity nanosandwich is fabricated through attaching polymetformin (PolyMet) onto photothermal agent black phosphorus nanosheets (BP). PolyMet activates AMPK to inhibit adipogenesis, promote browning, and mitigate AT inflammation by decreasing macrophage infiltration, repolarizing macrophage phenotype, and downregulating pro-inflammatory cytokines. Additionally, BP induces lipolysis and apoptosis of adipocytes and macrophages through a photothermal effect. By further functionalization using hyaluronic acid (HA) and MMP2 substrate-linking P3 peptide-modified HA (P3-HA), an enhanced anti-obesity effect is obtained by dual-targeting of P3 and HA, and HA-mediated CD44 poly-clustering after MMP2 cleavage. Upon laser irradiation, the designed nanosandwich (P3-HA/PM@BP) effectively inhibits obesity development in obese mice, increases M2/M1 ratio in AT, reduces the serum levels of cholesterol/triglyceride and improves insulin sensitivity, exhibiting promising research potential to facilitate the clinical development of modern anti-obesity therapies.

Mitochondrial Reactive Oxygen Species Dysregulation in Heart Failure with Preserved Ejection Fraction: A Fraction of the Whole

Heart failure with preserved ejection fraction (HFpEF) is a multifarious syndrome, accounting for over half of heart failure (HF) patients receiving clinical treatment. The prevalence of HFpEF is rapidly increasing in the coming decades as the global population ages. It is becoming clearer that HFpEF has a lot of different causes, which makes it challenging to find effective treatments. Currently, there are no proven treatments for people with deteriorating HF or HFpEF. Although the pathophysiologic foundations of HFpEF are complex, excessive reactive oxygen species (ROS) generation and increased oxidative stress caused by mitochondrial dysfunction seem to play a critical role in the pathogenesis of HFpEF. Emerging evidence from animal models and human myocardial tissues from failed hearts shows that mitochondrial aberrations cause a marked increase in mitochondrial ROS (mtROS) production and oxidative stress. Furthermore, studies have reported that common HF medications like beta blockers, angiotensin receptor blockers, angiotensin-converting enzyme inhibitors, and mineralocorticoid receptor antagonists indirectly reduce the production of mtROS. Despite the harmful effects of ROS on cardiac remodeling, maintaining mitochondrial homeostasis and cardiac functions requires small amounts of ROS. In this review, we will provide an overview and discussion of the recent findings on mtROS production, its threshold for imbalance, and the subsequent dysfunction that leads to related cardiac and systemic phenotypes in the context of HFpEF. We will also focus on newly discovered cellular and molecular mechanisms underlying ROS dysregulation, current therapeutic options, and future perspectives for treating HFpEF by targeting mtROS and the associated signal molecules.

Effects of glucocorticoids on adipose tissue plasticity

Glucocorticoids (GCs) play an important role in metabolic adaptation, regulating carbohydrate-lipid homeostasis and the immune system. Because they also have anti-inflammatory and immunosuppressive properties, synthetic analogues of GCs have been developed and are widely used in the treatment of chronic inflammatory conditions and in organ transplantation. GCs are among the most commonly prescribed drugs in the world. However, long term and high GC doses can cause side effects such as GC-induced diabetes and lipodystrophy. In recent years, a large number of independent studies have reported the effects of constitutive and adipocyte-specific deletion of the GC receptor (GR) in mice under different diets and treatments, resulting in contrasting phenotypes. To avoid potential compensatory mechanisms associated with the constitutive adipocyte GR silencing during adipose tissue development, our team has generated an inducible mouse model of GR deletion specifically in the adipocyte (AdipoGR-KO). Using this mouse model, we were able to demonstrate the critical role of the adipocyte GR in GC-induced metabolic changes. Indeed, under conditions of hypercorticism, AdipoGR-KO mice showed an improvement in glucose tolerance and insulin sensitivity, as well as in lipid profile, despite a massive increase in adiposity. This result is explained by a densification of adipose tissue vascularization, highlighting the repressive role of adipocyte GR in the healthy expansion of this tissue. Our work has largely contributed to the demonstration of the important role of the adipocyte GR in the physiology and pathophysiology of the adipose tissue and its impact on energy homeostasis.

The molecular mechanism of macrophage-adipocyte crosstalk in maintaining energy homeostasis

Interactions between macrophages and adipocytes in adipose tissue are critical for the regulation of energy metabolism and obesity. Macrophage polarization induced by cold or other stimulations can drive metabolic reprogramming of adipocytes, browning, and thermogenesis. Accordingly, investigating the roles of macrophages and adipocytes in the maintenance of energy homeostasis is critical for the development of novel therapeutic approaches specifically targeting macrophages in metabolic disorders such as obesity. Current review outlines macrophage polarization not only regulates the release of central nervous system and inflammatory factors, but controls mitochondrial function, and other factor that induce metabolic reprogramming of adipocytes and maintain energy homeostasis. We also emphasized on how the adipocytes conversely motivate the polarization of macrophage. Exploring the interactions between adipocytes and macrophages may provide new therapeutic strategies for the management of obesity-related metabolic diseases.

Effects of the mineralocorticoid receptor antagonist eplerenone in experimental autoimmune encephalomyelitis

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

Clinical and biochemical outcomes after adrenalectomy for primary aldosteronism in tertiary and quaternary referral centers: data from SOPRANO study

Hypertension cure following adrenalectomy in unilateral primary aldosteronism (PA) remains uncertain. Previous meta-analyses have shown highly variable surgical outcomes. Our study aimed to determine the unknown proportion of complete clinical and biochemical success in tertiary and quaternary referral centers. We conducted a systematic review and meta-analysis of studies reporting surgical outcomes of unilateral PA patients within the Surgical Outcome of PRimary Aldosteronism progNostic mOdels (SOPRANO) study. From 27 publications we identified 32 eligible studies, of which 22 were judged to be at low risk of bias. Eighteen were single-center studies, while fourteen were multi-center studies, with patients recruited from 132 referral centers worldwide. Adrenalectomy was performed on 5887 patients, with 4861 (83%) included in the final analysis. The pooled estimates of complete clinical and biochemical success for all studies were 39% (95% CI: 34-44%) and 99% (95% CI: 96-99%), respectively, similar to that found for studies at low risk of bias. Multivariate meta-regression analyses for all studies and low-bias risk studies revealed that BMI (P < 0.01), recruitment time period (P < 0.01), and hypertension duration (P < 0.05) inversely correlated with complete clinical success, while BMI (P < 0.05) and the number of enrolled centers (P < 0.05) inversely correlated with complete biochemical success. In summary, our findings offer robust estimates of complete clinical and biochemical success rates following adrenalectomy for unilateral PA in tertiary and quaternary referral centers and identify new potential effect modifiers that can help clinicians to inform and counsel patients about post-surgery expectations, guaranteeing effective treatment and ultimately enhancing outcomes.

Renoprotective Effects of Mineralocorticoid Receptor Antagonists Against Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a growing epidemic worldwide and a leading cause of end-stage kidney disease. Mineralocorticoid receptor (MR) blockade using Finerenone is a recently approved therapeutic approach to slow down the progression of DKD in patients with type 2 diabetes in addition to other therapies such as angiotensin-II converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), sodium-glucose co-transporter 2 (SGLT2) inhibitors, and glucagon-like peptide 1 (GLP-1) analogs. This review elaborates on the pathophysiologic pathways activated by aldosterone (the human mineralocorticoid) in DKD, the pharmacology of three different generations of mineralocorticoid receptor antagonists (MRAs), specifically, spironolactone, eplerenone, and finerenone, and the mechanisms by which these MRAs elicit their protective effects on the kidney under diabetic settings.

Mineralocorticoid receptor overactivation: targeting systemic impact with non-steroidal mineralocorticoid receptor antagonists

The overactivation of the mineralocorticoid receptor (MR) promotes pathophysiological processes related to multiple physiological systems, including the heart, vasculature, adipose tissue and kidneys. The inhibition of the MR with classical MR antagonists (MRA) has successfully improved outcomes most evidently in heart failure. However, real and perceived risk of side effects and limited tolerability associated with classical MRA have represented barriers to implementing MRA in settings where they have been already proven efficacious (heart failure with reduced ejection fraction) and studying their potential role in settings where they might be beneficial but where risk of safety events is perceived to be higher (renal disease). Novel non-steroidal MRA have distinct properties that might translate into favourable clinical effects and better safety profiles as compared with MRA currently used in clinical practice. Randomised trials have shown benefits of non-steroidal MRA in a range of clinical contexts, including diabetic kidney disease, hypertension and heart failure. This review provides an overview of the literature on the systemic impact of MR overactivation across organ systems. Moreover, we summarise the evidence from preclinical studies and clinical trials that have set the stage for a potential new paradigm of MR antagonism.

Influence of Perivascular Adipose Tissue on Microcirculation: A Link Between Hypertension and Obesity

Alterations in microcirculation play a crucial role in the pathogenesis of cardiovascular and metabolic disorders such as obesity and hypertension. The small resistance arteries of these patients show a typical remodeling, as indicated by an increase of media or total wall thickness to lumen diameter ratio that impairs organ flow reserve. The majority of blood vessels are surrounded by a fat depot which is termed perivascular adipose tissue (PVAT). In recent years, data from several studies have indicated that PVAT is an endocrine organ that can produce a variety of adipokines and cytokines, which may participate in the regulation of vascular tone, and the secretory profile varies with adipocyte phenotype and disease status. The PVAT of lean humans largely secretes the vasodilator adiponectin, which will act in a paracrine fashion to reduce peripheral resistance and improve nutrient uptake into tissues, thereby protecting against the development of hypertension and diabetes. In obesity, PVAT becomes enlarged and inflamed, and the bioavailability of adiponectin is reduced. The inevitable consequence is a rise in peripheral resistance with higher blood pressure. The interrelationship between obesity and hypertension could be explained, at least in part, by a cross-talk between microcirculation and PVAT. In this article, we propose an integrated pathophysiological approach of this relationship, in order to better clarify its role in obesity and hypertension, as the basis for effective and specific prevention and treatment.

Inflammation in Heart Failure-Future Perspectives

Chronic heart failure is a terminal point of a vast majority of cardiac or extracardiac causes affecting around 1-2% of the global population and more than 10% of the people above the age of 65. Inflammation is persistently associated with chronic diseases, contributing in many cases to the progression of disease. Even in a low inflammatory state, past studies raised the question of whether inflammation is a constant condition, or if it is, rather, triggered in different amounts, according to the phenotype of heart failure. By evaluating the results of clinical studies which focused on proinflammatory cytokines, this review aims to identify the ones that are independent risk factors for heart failure decompensation or cardiovascular death. This review assessed the current evidence concerning the inflammatory activation cascade, but also future possible targets for inflammatory response modulation, which can further impact the course of heart failure.

Mineralocorticoid Receptor Antagonism Prevents Type 2 Familial Partial Lipodystrophy Brown Adipocyte Dysfunction

Type-2 Familial Partial Lipodystrophy (FPLD2), a rare lipodystrophy caused by LMNA mutations, is characterized by a loss of subcutaneous fat from the trunk and limbs and excess accumulation of adipose tissue in the neck and face. Several studies have reported that the mineralocorticoid receptor (MR) plays an essential role in adipose tissue differentiation and functionality. We previously showed that brown preadipocytes isolated from a FPLD2 patient's neck aberrantly differentiate towards the white lineage. As this condition may be related to MR activation, we suspected altered MR dynamics in FPLD2. Despite cytoplasmic MR localization in control brown adipocytes, retention of MR was observed in FPLD2 brown adipocyte nuclei. Moreover, overexpression of wild-type or mutated prelamin A caused GFP-MR recruitment to the nuclear envelope in HEK293 cells, while drug-induced prelamin A co-localized with endogenous MR in human preadipocytes. Based on in silico analysis and in situ protein ligation assays, we could suggest an interaction between prelamin A and MR, which appears to be inhibited by mineralocorticoid receptor antagonism. Importantly, the MR antagonist spironolactone redirected FPLD2 preadipocyte differentiation towards the brown lineage, avoiding the formation of enlarged and dysmorphic lipid droplets. Finally, beneficial effects on brown adipose tissue activity were observed in an FPLD2 patient undergoing spironolactone treatment. These findings identify MR as a new lamin A interactor and a new player in lamin A-linked lipodystrophies.

Blockade of the mineralocorticoid receptor improves markers of human endothelial cell dysfunction and hematological indices in a mouse model of sickle cell disease

Increased endothelin-1 (ET-1) levels in patients with sickle cell disease (SCD) and transgenic mouse models of SCD contribute to disordered hematological, vascular, and inflammatory responses. Mineralocorticoid receptor (MR) activation by aldosterone, a critical component of the Renin-Angiotensin-Aldosterone-System, modulates inflammation and vascular reactivity, partly through increased ET-1 expression. However, the role of MR in SCD remains unclear. We hypothesized that MR blockade in transgenic SCD mice would reduce ET-1 levels, improve hematological parameters, and reduce inflammation. Berkeley SCD (BERK) mice, a model of severe SCD, were randomized to either sickle standard chow or chow containing the MR antagonist (MRA), eplerenone (156 mg/Kg), for 14 days. We found that MRA treatment reduced ET-1 plasma levels (p = .04), improved red cell density gradient profile (D50 ; p < .002), and increased mean corpuscular volume in both erythrocytes (p < .02) and reticulocytes (p < .024). MRA treatment also reduced the activity of the erythroid intermediate-conductance Ca2+ -activated K+ channel - KCa 3.1 (Gardos channel, KCNN4), reduced cardiac levels of mRNAs encoding ET-1, Tumor Necrosis Factor Receptor-1, and protein disulfide isomerase (PDI) (p < .01), and decreased plasma PDI and myeloperoxidase activity. Aldosterone (10-8  M for 24 h in vitro) also increased PDI mRNA levels (p < .01) and activity (p < .003) in EA.hy926 human endothelial cells, in a manner blocked by pre-incubation with the MRA canrenoic acid (1 μM; p < .001). Our results suggest a novel role for MR activation in SCD that may exacerbate SCD pathophysiology and clinical complications.

Adiposity, aldosterone and plasma renin activity among African Americans: The Jackson Heart Study

Objective

To analyze associations between adiposity and the renin-angiotensin-aldosterone system (RAAS) in a large African American (AA) cohort.

Methods

Cross-sectional associations of adiposity (body mass index [BMI], waist circumference [WC], waist:height ratio, waist:hip ratio, leptin, adiponectin, leptin:adiponectin ratio [LAR], subcutaneous [SAT] and visceral adipose tissue [VAT], and liver attenuation [LA]) with aldosterone, plasma renin activity (renin), and aldosterone:renin ratio (ARR) were assessed in the Jackson Heart Study using adjusted linear regression models.

Results

A 1-SD higher BMI was associated with a 4.8 % higher aldosterone, 9.4 % higher renin, and 5.0 % lower ARR (all p < 0.05). Log-leptin had the largest magnitude of association with renin (30.2 % higher) and ARR (9.6 % lower), while the strongest association of aldosterone existed for log-LAR (15.3 % higher) (all 1-SD, p < 0.05). SAT was only associated with renin. VAT was associated with higher aldosterone, renin, and ARR. Liver fat was associated with aldosterone and renin, but not ARR. Associations of WC, BMI, and SAT with aldosterone were greater in men while the association with VAT was greater in women (p-interactions < 0.05).

Conclusion

Multiple measures of adiposity are associated with the RAAS in AAs. Further studies should examine the role of RAAS in obesity-driven cardiometabolic diseases.

Shared biological mechanisms of depression and obesity: focus on adipokines and lipokines

Depression and obesity are both common disorders currently affecting public health, frequently occurring simultaneously within individuals, and the relationship between these disorders is bidirectional. The association between obesity and depression is highly co-morbid and tends to significantly exacerbate metabolic and related depressive symptoms. However, the neural mechanism under the mutual control of obesity and depression is largely inscrutable. This review focuses particularly on alterations in systems that may mechanistically explain the in vivo homeostatic regulation of the obesity and depression link, such as immune-inflammatory activation, gut microbiota, neuroplasticity, HPA axis dysregulation as well as neuroendocrine regulators of energy metabolism including adipocytokines and lipokines. In addition, the review summarizes potential and future treatments for obesity and depression and raises several questions that need to be answered in future research. This review will provide a comprehensive description and localization of the biological connection between obesity and depression to better understand the co-morbidity of obesity and depression.

Body mass index and clinical outcomes in patients with heart failure with preserved ejection fraction mediated by diastolic blood pressure status?

Background

The "obesity paradox" has been elucidated in patients with heart failure (HF). Current guidelines introduce a target diastolic blood pressure (DBP) < 80 mmHg but >70 mmHg in HF patients. Due to reduced coronary perfusion, low DBP has a deleterious impact on cardiovascular outcomes. This present study aimed to assess the relationship between BMI and adjudicated clinical outcomes in HFpEF patients according to the status of DBP.

Methods

We analyzed the data in 1749 HFpEF patients from the Americas of the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist) Trial. The population was stratified by DBP (<70 mmHg, and ≥70 mmHg) and BMI strata (normal weight, overweight, and obesity). Cox proportional hazards models and competing-risks regression analysis were performed.

Results

At baseline, the median BMI and DBP were 32.9 kg/m² (interquartile range 28.0-38.5 kg/m²) and 70 mmHg (interquartile range 62-80 mmHg), respectively. In the multivariable analysis, obesity was associated with better survival rates in the total HFpEF population (all-cause death: HR = 0.439, 95% CI 0.256-0.750; and cardiovascular death: HR = 0.378, 95% CI 0.182-0.787). In patients with DBP<70 mmHg, obesity was not significantly associated with reduced risks for all-cause death (HR = 0.531, 95% CI: 0.263-1.704) and cardiovascular death (HR = 0.680, 95% CI: 0.254-1.819). However, multivariate analyses for cardiovascular death (HR = 0.339, 95% CI: 0.117-0.983) and all-cause death (HR = 0.389, 95% CI: 0.156-0.969) were significant in patients with DBP≥70 mmHg. Nevertheless, there were no interactions between DBP and BMI.

Conclusions

The obesity paradox was observed in patients with HFpEF, regardless of DBP strata (<70 mmHg, and ≥70 mmHg).

Multi-omic analysis of the cardiac cellulome defines a vascular contribution to cardiac diastolic dysfunction in obese female mice

Coronary microvascular dysfunction (CMD) is associated with cardiac dysfunction and predictive of cardiac mortality in obesity, especially in females. Clinical data further support that CMD associates with development of heart failure with preserved ejection fraction and that mineralocorticoid receptor (MR) antagonism may be more efficacious in obese female, versus male, HFpEF patients. Accordingly, we examined the impact of smooth muscle cell (SMC)-specific MR deletion on obesity-associated coronary and cardiac diastolic dysfunction in female mice. Obesity was induced in female mice via western diet (WD) feeding alongside littermates fed standard diet. Global MR blockade with spironolactone prevented coronary and cardiac dysfunction in obese females and specific deletion of SMC-MR was sufficient to prevent obesity-associated coronary and cardiac diastolic dysfunction. Cardiac gene expression profiling suggested reduced cardiac inflammation in WD-fed mice with SMC-MR deletion independent of blood pressure, aortic stiffening, and cardiac hypertrophy. Further mechanistic studies utilizing single-cell RNA sequencing of non-cardiomyocyte cell populations revealed novel impacts of SMC-MR deletion on the cardiac cellulome in obese mice. Specifically, WD feeding induced inflammatory gene signatures in non-myocyte populations including B/T cells, macrophages, and endothelium as well as increased coronary VCAM-1 protein expression, independent of cardiac fibrosis, that was prevented by SMC-MR deletion. Further, SMC-MR deletion induced a basal reduction in cardiac mast cells and prevented WD-induced cardiac pro-inflammatory chemokine expression and leukocyte recruitment. These data reveal a central role for SMC-MR signaling in obesity-associated coronary and cardiac dysfunction, thus supporting the emerging paradigm of a vascular origin of cardiac dysfunction in obesity.

The role of aldosterone and ideal cardiovascular health in incident diabetes: The Jackson Heart Study

Background

Greater attainment of ideal cardiovascular health (ICH) and lower serum aldosterone are associated with lower diabetes risk. Higher levels of ICH are associated with lower aldosterone. The mediational role of aldosterone in the association of ICH with incident diabetes remains unexplored. Thus, we examined the mediational role of aldosterone in the association of 5 ICH components (smoking, diet, physical activity, body mass index [BMI], and cholesterol) with incident diabetes. Additionally, we investigated the mediational role of glucose and blood pressure (BP) in the association of aldosterone with incident diabetes in an African American (AA) cohort.

Methods

We conducted a prospective cohort analysis among AA adults, aged 21-94 years, in the Jackson Heart Study. Data on ICH, aldosterone, and cardiometabolic risk factors were collected at exam 1 (2000-2004). Diabetes (fasting glucose ≥ 126 mg/dL, physician diagnosis, use of diabetes drugs, or glycated hemoglobin ≥ 6.5%) was assessed at exams 1 through 3 (2009-2012). ICH metrics were defined by American Heart Association 2020 goals for smoking, dietary intake, physical activity, BMI, total cholesterol, BP and glucose. The number of ICH metrics attained at exam 1, excluding BP and fasting glucose, were summed (0-2, vs. 3+). R Package Mediation was used to examine: 1) The mediational role of aldosterone in the association of ICH with incident diabetes; and 2) the mediational role of BP and glucose in the association of aldosterone with incident diabetes.

Results

Among 2,791 participants (mean age: 53±12, 65% female) over a median of 7.5 years, there were 497 incident diabetes cases. Risk of incident diabetes was 37% (HR: 0.63, 95%CI: 0.47, 0.84) lower in 3+ ICH category compared to 0-2 ICH category. Aldosterone mediated 6.98% (95% CI: 1.8%, 18.0%) of the direct effect of ICH on incident diabetes. A 1-unit increase in log-aldosterone was associated with a 44% higher risk of diabetes (HR 1.44, 95%CI 1.25-1.64). BP and glucose mediated 16.3% (95% CI: 7.0%, 31.0%) and 19.7% (95% CI: 6.5%, 34.0%) of the association of aldosterone with incident diabetes, respectively.

Conclusion

Aldosterone is a mediator of the association of ICH with incident diabetes, whereas BP and glucose are mediators of the association of aldosterone with incident diabetes, emphasizing the importance of the renin-angiotensin-aldosterone system and ICH in lowering risk of diabetes in AA populations.

Effect of the interaction between the visceral-to-subcutaneous fat ratio and aldosterone on cardiac function in patients with primary aldosteronism

Primary aldosteronism is the most frequent secondary hypertensive disease and is characterized by an elevated risk for cardiovascular disease. The current standard treatments are adrenalectomy and/or administration of mineralocorticoid receptor blockers, both of which are effective at ameliorating hypertension via intervention for hyperaldosteronism. However, both of these approaches have side effects and contraindications, and mineralocorticoid receptor blockers also have limited preventive efficacy against cardiovascular events. Recently, in vitro experiments have shown that aldosterone regulation is closely related to abdominal fat accumulation and that there is crosstalk between aldosterone and visceral fat tissue accumulation. We previously reported that this interaction was clinically significant in renal dysfunction; however, its effects on the heart remain unclear. Here, we analyzed data from 49 patients with primary aldosteronism and 29 patients with essential hypertension to examine the potential effect of the interaction between the ratio of visceral-to-subcutaneous fat tissue volume and the plasma aldosterone concentration on echocardiographic indices, including the tissue Doppler-derived E/e' ratio. A significant interaction was found in patients with primary aldosteronism (p < 0.05), indicating that patients with the combination of a high plasma aldosterone concentration and high visceral-to-subcutaneous fat ratio show an increased E/e' ratio, which is a well-known risk factor for future cardiovascular events. Our results confirm the clinical importance of the interaction between aldosterone and abdominal fat tissue, suggesting that an improvement in the visceral-to-subcutaneous fat ratio may be synergistically and complementarily effective in reducing the elevated risk of cardiovascular disease in patients with primary aldosteronism when combined with conventional therapies for reducing aldosterone activity. A significant effect of the interaction between plasma aldosterone concentration and the visceral-to-subcutaneous fat ratio on the tissue Doppler-derived E/e' ratio in patients with primary aldosteronism.

Obesity and heart failure with preserved ejection fraction: new insights and pathophysiological targets

Obesity and heart failure with preserved ejection fraction (HFpEF) represent two intermingling epidemics driving perhaps the greatest unmet health problem in cardiovascular medicine in the 21st century. Many patients with HFpEF are either overweight or obese, and recent data have shown that increased body fat and its attendant metabolic sequelae have widespread, protean effects systemically and on the cardiovascular system leading to symptomatic HFpEF. The paucity of effective therapies in HFpEF underscores the importance of understanding the distinct pathophysiological mechanisms of obese HFpEF to develop novel therapies. In this review, we summarize the current understanding of the cardiovascular and non-cardiovascular features of the obese phenotype of HFpEF, how increased adiposity might pathophysiologically contribute to the phenotype, and how these processes might be targeted therapeutically.

Secondary diabetes mellitus due to primary aldosteronism

Primary aldosteronism (PA) and diabetes mellitus (DM) are clinical conditions that increase cardiovascular risk. Approximately one in five patients with PA have DM. Nevertheless, the pathophysiology linking these two entities is not entirely understood. In addition, the majority of patients with PA have glucocorticoid co-secretion, which is associated with increased risk of impaired glucose homeostasis. In the present review, we aim to comprehensively discuss all the available research data concerning the interplay between mineralocorticoid excess and glucose metabolism, with separate analysis of the sequalae in muscle, adipose tissue, liver and pancreas. Aldosterone binds both mineralocorticoid and glucocorticoid receptors and amplifies tissue glucocorticoid activity, via 11-β-hydroxysteroid dehydrogenase type 1 stimulation. A clear classification of the molecular events as per specific receptor in insulin-sensitive tissues is impossible, while their synergistic interaction is plausible. Furthermore, aldosterone induces oxidative stress and inflammation, perturbs adipokine expression, thermogenesis and lipogenesis in adipose tissue, and increases hepatic steatosis. In pancreas, enhanced oxidative stress and inflammation of beta cells, predominantly upon glucocorticoid receptor activation, impair insulin secretion. No causality between hypokalemia and impaired insulin response is yet proven; in contrast, hypokalemia appears to be implicated with insulin resistance and hepatic steatosis. The superior efficacy of adrenalectomy in ameliorating glucose metabolism vs. mineralocorticoid receptor antagonists in clinical studies highlights the contribution of non-mineralocorticoid receptor-mediated mechanisms in the pathophysiologic process. The exact role of hypokalemia, the mechanisms linking mineralocorticoid excess with hepatic steatosis, and possible disease-modifying role of pioglitazone warrant further studies.

Association between Use of Spironolactone and Risk of Stroke in Hypertensive Patients: A Cohort Study

Objective: to investigate the relationship between the use of spironolactone and the risk of stroke in hypertensive patients. Methods: a total of 2464 spironolactone users and 12,928 non-users were identified (unmatched original cohort), and 1:1 matched pairs of 2461 spironolactone users and 2461 non-users based on propensity scores were created (propensity-score-matched cohort). Results: In the unmatched original cohort, the unadjusted analysis showed that the use of spironolactone was associated with a lower risk of total stroke (HR, 0.71; 95% CI, 0.61−0.84; p < 0.001), which was sustained in the adjusted analysis. According to stroke type, the association was with ischemic strokes (propensity-score-adjusted HR, 0.71; 95% CI, 0.59−0.85; p < 0.001) and hemorrhagic ones (propensity-score-adjusted HR, 0.63; 95% CI, 0.45−0.88; p = 0.008). Similar results were shown in the propensity-score-matched cohort. The results of the subgroup and sensitivity analyses were consistent with those of the primary analysis. The dose−response analysis demonstrated a dose-dependent association of spironolactone with a lower risk of stroke in hypertensive patients. Conclusions: The use of spironolactone was associated with a significantly lower risk of stroke events in hypertensive patients. Further research, including prospective randomized clinical trials, is needed to validate our findings.

Obesity and sudden cardiac death: Prevalence, pathogenesis, prevention and intervention

Obesity and sudden cardiac death (SCD) share common risk factors. Obesity, in and of itself, can result in the development of SCD. Numerous epidemiologic and clinical studies have demonstrated the close relationships between obesity and SCD, however, the underlying mechanisms remain incompletely understood. Various evidences support the significance of excess adiposity in determining the risk of SCD, including anatomical remodeling, electrical remodeling, metabolic dysfunction, autonomic imbalance. Weight reduction has improved obesity related comorbidities, and reversed abnormal cardiac remodeling. Indeed, it is still unknown whether weight loss contributes to decreased risk of SCD. Further high-quality, prospective trials are needed to strengthen our understanding on weight management and SCD.

Nonsteroidal Mineralocorticoid Receptor Antagonist Eliciting Cardiorenal Protection Is a New Option for Patients with Chronic Kidney Disease

Background

Mineralocorticoid receptor antagonists (MRAs) protect cardiorenal function by robust anti-inflammatory and antifibrotic functions beyond classical functions of maintaining fluid and electrolyte homeostasis. The application of traditional steroidal MRAs to chronic kidney disease (CKD) has been limited by adverse events, especially when combined with renin-angiotensin system inhibitors, guideline-recommend drugs for CKD patients. Recently, the development of nonsteroidal MRAs gives patients with CKD a promising option.

Summary

The discovery of nonsteroidal MRAs is based on the molecular structure of the mineralocorticoid receptor (MR) and differs in structure from spironolactone, a progesterone derivative. The structure of nonsteroidal MRAs determines their more effective and selective inhibition of MR providing patients more benefits with fewer adverse effects than MRAs. Recently, two types of nonsteroidal MRAs, finerenone and esaxerenone, have been authorized for clinical use. We elaborate on the physiological and pathophysiological mechanisms of MR, review the history of MRAs, compare two generations of MRAs, and introduce the forward clinical trials of finerenone and esaxerenone.

Key Messages

Finerenone reduces the cardiovascular and kidney composite outcomes in diabetic patients with CKD eliciting a cardiorenal protection effect. Esaxerenone can effectively reduce blood pressure in hypertensive patients and albuminuria in diabetic patients with CKD. The risk of hyperkalemia is controllable and acceptable through the serum potassium-based dose titrate. Combination therapy with sodium-glucose cotransport-2 inhibition or a new potassium binder may be a safer and more efficient approach.

Adipose Tissue Dysfunction in Obesity: Role of Mineralocorticoid Receptor

The mineralocorticoid receptor (MR) acts as an essential regulator of blood pressure, volume status, and electrolyte balance. However, in recent decades, a growing body of evidence has suggested that MR may also have a role in mediating pro-inflammatory, pro-oxidative, and pro-fibrotic changes in several target organs, including the adipose tissue. The finding that MR is overexpressed in the adipose tissue of patients with obesity has led to the hypothesis that this receptor can contribute to adipokine dysregulation and low-grade chronic inflammation, alterations that are linked to the development of obesity-related metabolic and cardiovascular complications. Moreover, several studies in animal models have investigated the role of MR antagonists (MRAs) in preventing the metabolic alterations observed in obesity. In the present review we will focus on the potential mechanisms by which MR activation can contribute to adipose tissue dysfunction in obesity and on the possible beneficial effects of MRAs in this setting.

Host factors associated with either VP16 or VP16-induced complex differentially affect HSV-1 lytic infection

Herpes simplex virus type 1 (HSV-1) is an important human pathogen with neurotropism. Following lytic infection in mucosal or skin epithelium, life-long latency is established mainly in sensory neurons, which can periodically reactivate by stress, leading to recurrent disease and virus transmission. During the virus's productive infection, the tegument protein VP16, a component of HSV-1 virion, is physically associated with two cellular factors, host cell factor-1 (HCF-1), and POU domain protein Oct-1, to construct the VP16-induced complex, which is essential to stimulate immediate early (IE)-gene transcription as well as initiate the lytic programme. Apart from HCF-1 and Oct-1, VP16 also associates with a series of other host factors, making a VP16-induced regulatory switch to either activate or inactivate virus gene transcription. In addition, VP16 has effects on distinct signalling pathways via binding to various host molecules that are essentially related to innate immune responses, RNA polymerases, molecular chaperones, and virus infection-induced host shutoff. VP16 also functionally compensates for given host factors, such as PPAR-γ and ß-catenin. In this review, we provide an overview of the updated insights on the interplay between VP16 and the host factors that coordinate virus infection.

Targeting efficacy of spironolactone in patients with heart failure with preserved ejection fraction: the TOPCAT study

AIMS

We aimed to explore the heterogeneous treatment effects (HTEs) for spironolactone treatment in patients with Heart failure with preserved ejection fraction (HFpEF) and examine the efficacy and safety of spironolactone medication, ensuring a better individualized therapy.

METHODS AND RESULTS

We used the causal forest algorithm to discover the heterogeneous treatment effects (HTEs) from patients in the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial. Cox regressions were performed to assess the hazard ratios (HRs) of spironolactone medication for cardiovascular death and drug discontinuation in each group. The causal forest model revealed three representative covariates and participants were partitioned into four subgroups which were Group 1 (baseline BMI ≤ 31.71 kg/m² and baseline ALP ≤ 80 U/L, n = 759); Group 2 (BMI ≤ 31.71 kg/m² and ALP > 80 U/L, n = 1088); Group 3 (BMI > 31.71 kg/m² , and WBC ≤ 6.6 cells/μL, n = 633); Group 4 (BMI > 31.71 kg/m² and WBC > 6.6 cells/μL, n = 832), respectively. In the four subgroups, spironolactone therapy reduced the risk of cardiovascular death in high-risk group (Group 4) with both high BMI and WBC count (HR: 0.76; 95% CI 0.58 to 0.99; P = 0.045) but increased the risk in low-risk group (Group 1) with both low BMI and ALP (HR: 1.45; 95% CI 1.02 to 2.07; P = 0.041; P for interaction = 0.020) but showed similar risk of drug discontinuation (P for interaction = 0.498).

CONCLUSION

Our study manifested the HTEs of spironolactone in patients with HFpEF. Spironolactone treatment in HFpEF patients is feasible and effective in patients with high BMI and WBC while harmful in patients with low BMI and ALP. Machine learning model could be meaningful for improved categorization of patients with HFpEF, ensuring a better individualized therapy in the clinical setting.

Cardiorenal benefits of mineralocorticoid antagonists in CKD and type 2 diabetes : Lessons from the FIGARO-DKD trial

Diabetic kidney disease (DKD) develops in almost half of all patients with diabetes and is the most common cause of chronic kidney disease (CKD) worldwide. Despite the high risk of chronic renal failure in these patients, only few therapeutic strategies are available. The use of renin-angiotensin system blockers to reduce the incidence of kidney failure in patients with DKD was established years ago and remains the hallmark of therapy. The past 2 years have seen a dramatic change in our therapeutic arsenal for CKD. Sodium-glucose co-transporter‑2 inhibitors (SGLT2s) have been successfully introduced for the treatment of CKD. A further addition is a novel compound antagonizing the activation of the mineralocorticoid receptor: finerenone. Finerenone reduces albuminuria and surrogate markers of cardiovascular disease in patients who are already on optimal therapy. In the past, treatment with other mineralocorticoid receptor antagonists was hampered by a significantly increased risk of hyperkalemia. Finerenone had a much smaller effect on hyperkalemia. Together with a reduced effect on blood pressure and no signs of gynecomastia, this therapeutic strategy had a more specific anti-inflammatory effect and a smaller effect on the volume/electrolyte axis. In the FIDELIO-DKD study comparing the actions of the non-steroidal mineralocorticoid receptor antagonist finerenone with placebo, finerenone reduced the progression of DKD and the incidence of cardiovascular events, with a relatively safe adverse event profile. In this article, we summarize the available evidence on the cardioprotective and nephroprotective effects of finerenone and analyze the molecular mechanisms involved. In addition, we discuss the potential future role of mineralocorticoid receptor inhibition in the treatment of patients with diabetic CKD.

Esaxerenone, a selective mineralocorticoid receptor blocker, improves insulin sensitivity in mice consuming high-fat diet

BACKGROUND

Esaxerenone is a novel, non-steroidal selective mineralocorticoid receptor (MR) blocker. MR activation plays a crucial role in the development of cardiovascular and metabolic diseases. In this study, we investigated the effects of esaxerenone on various metabolic parameters in mice.

MATERIALS AND METHODS

Esaxerenone (3 mg/kg/day) was orally administered to high-fat diet (HFD)-fed male C57BL/6 mice. Mice fed a normal diet (ND) served as controls. Glucose and insulin tolerance, plasma lipid levels, and transaminase levels were assessed as metabolic parameters. Macrophage accumulation in the adipose tissue was evaluated using histological analysis. 3T3-L1 adipocytes, HepG2 cells, and C2C12 myotubes were used for in vitro experiments. Gene expression and insulin signaling were examined using quantitative RT-PCR and western blotting, respectively.

RESULTS

HFD successfully induced insulin resistance compared with that in ND. Esaxerenone ameliorated insulin resistance (P < 0.05) without altering other metabolic parameters, such as the lipid profile. Esaxerenone administration tended to decrease plasma transaminase levels compared with those in the non-treated group. In the adipose tissue, esaxerenone decreased macrophage accumulation (P < 0.05) and increased the expression levels of adiponectin and PPARγ. Aldosterone significantly decreased the expression levels of PPARγ and adiponectin in 3T3-L1 adipocytes. Furthermore, aldosterone attenuated insulin-induced Akt phosphorylation in 3T3-L1 adipocytes, HepG2 cells, and C2C12 myotubes in a dose-dependent manner (P < 0.01). These effects were ameliorated by pretreatment with esaxerenone.

CONCLUSION

Esaxerenone ameliorated insulin resistance in HFD-fed mice. Reduction of inflammation and improvement in insulin signaling may underlie the beneficial effects of esaxerenone.

Primary Aldosteronism and Resistant Hypertension: A Pathophysiological Insight

Primary aldosteronism (PA) is a pathological condition characterized by an excessive aldosterone secretion; once thought to be rare, PA is now recognized as the most common cause of secondary hypertension. Its prevalence increases with the severity of hypertension, reaching up to 29.1% in patients with resistant hypertension (RH). Both PA and RH are "high-risk phenotypes", associated with increased cardiovascular morbidity and mortality compared to non-PA and non-RH patients. Aldosterone excess, as occurs in PA, can contribute to the development of a RH phenotype through several mechanisms. First, inappropriate aldosterone levels with respect to the hydro-electrolytic status of the individual can cause salt retention and volume expansion by inducing sodium and water reabsorption in the kidney. Moreover, a growing body of evidence has highlighted the detrimental consequences of "non-classical" effects of aldosterone in several target tissues. Aldosterone-induced vascular remodeling, sympathetic overactivity, insulin resistance, and adipose tissue dysfunction can further contribute to the worsening of arterial hypertension and to the development of drug-resistance. In addition, the pro-oxidative, pro-fibrotic, and pro-inflammatory effects of aldosterone may aggravate end-organ damage, thereby perpetuating a vicious cycle that eventually leads to a more severe hypertensive phenotype. Finally, neither the pathophysiological mechanisms mediating aldosterone-driven blood pressure rise, nor those mediating aldosterone-driven end-organ damage, are specifically blocked by standard first-line anti-hypertensive drugs, which might further account for the drug-resistant phenotype that frequently characterizes PA patients.

Dysregulated Erythroid Mg2+ Efflux in Type 2 Diabetes

Hyperglycemia is associated with decreased Mg²⁺ content in red blood cells (RBC), but mechanisms remain unclear. We characterized the regulation of Mg²⁺ efflux by glucose in ex vivo human RBC. We observed that hemoglobin A_1C (HbA_1C) values correlated with Na⁺-dependent Mg²⁺ efflux (Na⁺/Mg²⁺ exchange) and inversely correlated with cellular Mg content. Treatment of cells with 50 mM D-glucose, but not with sorbitol, lowered total cellular Mg (2.2 ± 0.1 to 2.0 ± 0.1 mM, p < 0.01) and enhanced Na⁺/Mg²⁺ exchange activity [0.60 ± 0.09 to 1.12 ± 0.09 mmol/10¹³ cell × h (flux units, FU), p < 0.05]. In contrast, incubation with selective Src family kinase inhibitors PP2 or SU6656 reduced glucose-stimulated exchange activation (p < 0.01). Na⁺/Mg²⁺ exchange activity was also higher in RBC from individuals with type 2 diabetes (T2D, 1.19 ± 0.13 FU) than from non-diabetic individuals (0.58 ± 0.05 FU, p < 0.01). Increased Na⁺/Mg²⁺ exchange activity in RBC from T2D subjects was associated with lower intracellular Mg content. Similarly increased exchange activity was evident in RBC from the diabetic db/db mouse model as compared to its non-diabetic control (p < 0.03). Extracellular exposure of intact RBC from T2D subjects to recombinant peptidyl-N-glycosidase F (PNGase F) reduced Na⁺/Mg²⁺ exchange activity from 0.98 ± 0.14 to 0.59 ± 0.13 FU (p < 0.05) and increased baseline intracellular Mg content (1.8 ± 0.1 mM) to normal values (2.1 ± 0.1 mM, p < 0.05). These data suggest that the reduced RBC Mg content of T2D RBC reflects enhanced RBC Na⁺/Mg²⁺ exchange subject to regulation by Src family kinases and by the N-glycosylation state of one or more membrane proteins. The data extend our understanding of dysregulated RBC Mg²⁺ homeostasis in T2D.

Roles of Mineralocorticoid Receptors in Cardiovascular and Cardiorenal Diseases

Mineralocorticoid receptor (MR) activation in the heart and vessels leads to pathological effects, such as excessive extracellular matrix accumulation, oxidative stress, and sustained inflammation. In these organs, the MR is expressed in cardiomyocytes, fibroblasts, endothelial cells, smooth muscle cells, and inflammatory cells. We review the accumulating experimental and clinical evidence that pharmacological MR antagonism has a positive impact on a battery of cardiac and vascular pathological states, including heart failure, myocardial infarction, arrhythmic diseases, atherosclerosis, vascular stiffness, and cardiac and vascular injury linked to metabolic comorbidities and chronic kidney disease. Moreover, we present perspectives on optimization of the use of MR antagonists in patients more likely to respond to such therapy and review the evidence suggesting that novel nonsteroidal MR antagonists offer an improved safety profile while retaining their cardiovascular protective effects. Finally, we highlight future therapeutic applications of MR antagonists in cardiovascular injury.

Effects of mineralocorticoid receptor antagonists on sex hormones and body composition in patients with primary aldosteronism

Mineralocorticoid receptor antagonists are frequently used for the treatment of primary aldosteronism. Steroidal mineralocorticoid receptor antagonists may have antagonistic actions on androgen receptors, agonistic actions on progesterone receptors, and antagonistic actions on mineralocorticoid receptors. Because anti-androgen effects may cause body fat accumulation and skeletal muscle atrophy, there are concerns that this drug may have adverse effects on body composition. Therefore, in this randomized prospective study, we compared the adverse effects of spironolactone, a steroidal mineralocorticoid receptor antagonist, and esaxerenone, a nonsteroidal mineralocorticoid receptor antagonist, on sex hormone levels and body composition in patients with primary aldosteronism without severe renal dysfunction. The serum concentration of free testosterone was significantly higher in the spironolactone group than in the esaxerenone group in both males and females. However, the levels of estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone did not significantly increase. Changes in body fat percentage and muscle mass rate were not significantly different between the two groups. No patient showed a serum potassium level ≥6.0 mEq/L; however, serum potassium levels were significantly higher in the spironolactone group than in the esaxerenone group. These data indicate that spironolactone may have antagonistic effects on androgen receptors. Esaxerenone did not show any apparent adverse effects, suggesting that it can be safely used in patients with primary aldosteronism.

Mineralocorticoid receptor in non-alcoholic fatty liver disease

Liver diseases are the fourth common death in Europe responsible for about 2 million death per year worldwide. Among the known detrimental causes for liver dysfunction are virus infections, intoxications and obesity. The mineralocorticoid receptor (MR) is a ligand-dependent transcription factor activated by aldosterone or glucocorticoids but also by pathological milieu factors. Canonical actions of the MR take place in epithelial cells of kidney, colon and sweat glands and contribute to sodium reabsorption, potassium secretion and extracellular volume homeostasis. The non-canonical functions can be initiated by inflammation or an altered micro milieu leading to fibrosis, hypertrophy and remodeling in various tissues. This narrative review summarizes the evidence regarding the role of MR in portal hypertension, non-alcoholic fatty liver disease, liver fibrosis and cirrhosis, demonstrating that inhibition of the MR in vivo seems to be beneficial for liver function and not just for volume regulation. Unfortunately, the underlying molecular mechanisms are still not completely understood.

Coronary Vasculature and Myocardial Structure in HIV: Physiologic Insights From the Renin-Angiotensin-Aldosterone System

The landscape of HIV medicine dramatically changed with the advent of contemporary antiretroviral therapies, which has allowed persons with HIV (PWH) to achieve good virologic control, essentially eliminating HIV-related complications and increasing life expectancy. As PWH are living longer, noncommunicable diseases, such as cardiovascular disease (CVD), have become a leading cause of morbidity and mortality in PWH with rates that are 50% to 100% higher than in well-matched persons without HIV. In this review, we focus on disease of the coronary microvasculature and myocardium in HIV. We highlight a key hormonal system important to cardiovascular endocrinology, the renin-angiotensin-aldosterone system (RAAS), as a potential mediator of inflammatory driven-vascular and myocardial injury and consider RAAS blockade as a physiologically targeted strategy to reduce CVD in HIV.

High-fat and high-sodium diet induces metabolic dysfunction in the absence of obesity

OBJECTIVE

Excess dietary fat and sodium (NaCl) are both associated with obesity and metabolic dysfunction. In mice, high NaCl has been shown to block high-fat (HF) diet-induced weight gain. Here, the impact of an HF/NaCl diet on metabolic function in the absence of obesity was investigated.

METHODS

Wild-type mice were administered chow, NaCl (4%), HF, and HF/NaCl diets. Metabolic analysis was performed by measuring fasted blood glucose and insulin levels and by glucose tolerance test and insulin tolerance test.

RESULTS

After 10 weeks on diets, male and female mice on the HF diet gained weight, and HF/NaCl mice had significantly reduced weight gain similar to chow-fed mice. In the absence of obesity, HF/NaCl mice had significantly elevated fasting blood glucose and impaired glucose control during glucose tolerance tests. Both NaCl and HF/NaCl mice had decreased pancreas and β-cell mass. Administration of NaCl in drinking water did not protect mice from HF-diet-induced weight gain and obesity. Further analysis revealed that longer administration of HF/NaCl diets for 20 weeks resulted in significant weight gain and insulin resistance.

CONCLUSIONS

The data demonstrate that despite early inhibitory effects on fat deposition and weight gain, an HF/NaCl diet does not prevent the metabolic consequences of HF diet consumption.

Obesity, metabolic syndrome, and inflammation: an update for anaesthetists caring for patients with obesity

Our understanding of chronic inflammation in obesity is evolving. Suggested mechanisms include hypoxia of adipose tissue and a subsequent increase in circulating cytokines. It is now known that adipose tissue, far from being an inert tissue, produces and secretes multiple peptides that influence inflammation and metabolism, including substrates of the renin-angiotensin-aldosterone system (RAAS). RAAS blocking antihypertensive medication and cholesterol-lowering agents are now being evaluated for their metabolic and inflammation-modulating effects. Surgery also has pro-inflammatory effects, which may be exacerbated in patients with obesity. This narrative review will summarise the recent literature surrounding obesity, metabolic syndrome, inflammation, and interplay with the RAAS, with evidence-based recommendations for the optimisation of patients with obesity, prior to surgery and anaesthesia.

Nonsteroidal mineralcorticoid receptor antagonists: Novel therapeutic implication in the management of patients with type 2 diabetes

Growing evidencehas described a correlation between aldosterone, obesity, and insulin resistance, suggesting that adipocyte-related factors and mineralocorticoid receptor (MR) overactivation may alter aldosterone secretion, potentially leading to obesity and glucose intolerance. Preclinical studies showed that pharmacological antagonism of MR prevents white adipose tissue dysfunction(s) and expansion, activates brown adipose tissue, and improves glucose tolerance. The clinical use of nonsteroidal MR antagonists has been shown to reduce the risk of diabetic kidney disease progression and cardiovascular events in patients with diabetes. This review aims to summarize the effects of pharmacological MR blockade on obesity and its associated metabolic comorbidities, with a particular focus on the therapeutic implications of nonsteroidal MR antagonists in the management of patients with diabetes.

Inflammatory Cytokines, Immune Cells, and Organ Interactions in Heart Failure

Despite mounting evidence demonstrating the significance of inflammation in the pathophysiological mechanisms of heart failure (HF), most large clinical trials that target the inflammatory responses in HF yielded neutral or even worsening outcomes. Further in-depth understanding about the roles of inflammation in the pathogenesis of HF is eagerly needed. This review summarizes cytokines, cardiac infiltrating immune cells, and extracardiac organs that orchestrate the complex inflammatory responses in HF and highlights emerging therapeutic targets.

Role of mineralocorticoid receptor antagonists in kidney diseases

Mineralocorticoid receptor (MR) antagonists, for example, spironolactone and eplerenone, are in clinical use to treat hypertension. Increasing evidence suggests that mineralocorticoid receptor activation causes the pathogenesis and progression of chronic kidney disease. Aldosterone-induced MR activation increases inflammation, fibrosis, and oxidative stress in the kidney. MR antagonists (MRAs) have demonstrated therapeutic actions in chronic kidney disease (CKD), diabetic nephropathy (DN), renal fibrosis, and drug-induced renal injury in preclinical and clinical studies. We have summarized and discussed these studies in this review. The nonsteroidal MRA, esaxerenone, recently received approval for the treatment of hypertension. It has also shown a positive therapeutic effect in phase 3 clinical trials in patients with DN. Other nonsteroidal MRA such as apararenone, finerenone, AZD9977, and LY2623091 are in different clinical trials in patients with hypertension suffering from renal or hepatic fibrotic diseases. Hyperkalemia associated with MRA therapy has frequently led to the discontinuation of the treatment. The new generation nonsteroidal MRAs like esaxerenone are less likely to cause hyperkalemia at therapeutic doses. It appears that the nonsteroidal MRAs can provide optimum therapeutic benefit for patients suffering from kidney diseases.

Effect of Obesity on Response to Spironolactone in Patients With Heart Failure With Preserved Ejection Fraction

Obesity is common in heart failure with preserved ejection fraction (HFpEF). Whether obesity modifies the response to spironolactone in patients with HFpEF remains unclear. We aimed to investigate the effect of obesity, defined by body mass index (BMI) and waist circumference (WC), on response to spironolactone in patients with HFpEF enrolled in Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist trial. This was a post-hoc, exploratory analysis of the Americas cohort of Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist trial. BMI≥30 kg/m2 was used to define the obese group and WC≥102 cm in men and ≥88 cm in women were defined as high WC. In separate analyses, BMI and WC were treated as continuous variables. The effect of spironolactone versus placebo on outcomes was calculated by BMI and WC using Cox proportional hazard models. Obese patients were younger and had more co-morbidities. In multivariate analysis, spironolactone use was associated with a significant reduction in the primary end point, compared with placebo in obese [hazard ratio (HR = 0.618, 95% CI 0.460 to 0.831, p = 0.001), but not in nonobese subjects (HR = 0.946, 95% CI 0.623 to 1.437, p = 0.796; p for interaction = 0.056). There was a linear association between continuous BMI and the effect of spironolactone, with the effect becoming significant at 33kg/m². Similar results were obtained for the WC-based analysis. In conclusion, use of spironolactone in obese patients with HFpEF was associated with a decreased risk of the primary end point, cardiovascular death and HF hospitalizations, compared with placebo. Further prospective randomized studies in obese subjects are required.

Adipocyte-Mineralocorticoid Receptor Alters Mitochondrial Quality Control Leading to Mitochondrial Dysfunction and Senescence of Visceral Adipose Tissue

Mineralocorticoid receptor (MR) expression is increased in the adipose tissue (AT) of obese patients and animals. We previously demonstrated that adipocyte-MR overexpression in mice (Adipo-MROE mice) is associated with metabolic alterations. Moreover, we showed that MR regulates mitochondrial dysfunction and cellular senescence in the visceral AT of obese db/db mice. Our hypothesis is that adipocyte-MR overactivation triggers mitochondrial dysfunction and cellular senescence, through increased mitochondrial oxidative stress (OS). Using the Adipo-MROE mice with conditional adipocyte-MR expression, we evaluated the specific effects of adipocyte-MR on global and mitochondrial OS, as well as on OS-induced damage. Mitochondrial function was assessed by high throughput respirometry. Molecular mechanisms were probed in AT focusing on mitochondrial quality control and senescence markers. Adipo-MROE mice exhibited increased mitochondrial OS and altered mitochondrial respiration, associated with reduced biogenesis and increased fission. This was associated with OS-induced DNA-damage and AT premature senescence. In conclusion, targeted adipocyte-MR overexpression leads to an imbalance in mitochondrial dynamics and regeneration, to mitochondrial dysfunction and to ageing in visceral AT. These data bring new insights into the MR-dependent AT dysfunction in obesity.

Mineralocorticoid receptors in the pathogenesis of insulin resistance and related disorders: from basic studies to clinical disease

Aldosterone is a steroid hormone that regulates blood pressure and cardiovascular function by acting on renal and vascular mineralocorticoid receptors (MRs) to promote sodium retention and modulate endothelial function. Indeed, MRs are expressed in endothelial cells, vascular smooth muscle cells, adipocytes, immune cells, skeletal muscle cells, and cardiomyocytes. Excessive aldosterone and associated MR activation impair insulin secretion, insulin metabolic signaling to promote development of diabetes, and the related cardiometabolic syndrome. These adverse effects of aldosterone are mediated, in part, via increased inflammation, oxidative stress, dyslipidemia, and ectopic fat deposition. Therefore, inhibition of MR activation may have a beneficial effect in prevention of impaired insulin metabolic signaling, type 2 diabetes, and cardiometabolic disorders. This review highlights findings from the recent surge in research regarding MR-related cardiometabolic disorders as well as our contemporary understanding of the detrimental effects of excess MR activation on insulin metabolic signaling.

The mineralocorticoid receptor-an emerging player in metabolic syndrome?

Metabolic syndrome is a cluster of conditions that increase the risk of cardiovascular diseases, and comprises obesity, hypertension, impaired glucose metabolism and dyslipidaemia. It is well recognised that the mineralocorticoid receptor (MR) plays an important role in blood pressure regulation via its effect on salt and water retention in renal tubules, with hypertension being a key feature in primary aldosteronism patients with excess adrenal production of aldosterone, the primary ligand for MRs in the epithelial tissues. MRs are also expressed in a number of non-epithelial tissues including adipose tissue; in these tissues, glucocorticoids or cortisol can also activate MRs due to low levels of 11-beta-hydroxysteroid-dehydrogenase type 2 (11-βHSD2), the enzyme which inactivates cortisol. There is increasing evidence suggesting that over-activation of MRs plays a role in the pathophysiology of the other components of metabolic syndrome, promoting adiposity, inflammation and glucose intolerance, and that MR antagonists may confer beneficial effects on energy and substrate homeostasis and cardiometabolic diseases. This review discusses the advances in the literature shedding light on the MR as an emerging player in metabolic syndrome.