The endothelial mineralocorticoid receptor: Contributions to sex differences in cardiovascular disease

Cardiovascular Disease and Cancer: A Dangerous Liaison

The field of cardio-oncology has traditionally focused on the impact of cancer and its therapies on cardiovascular health. Mounting clinical and preclinical evidence, however, indicates that the reverse may also be true: cardiovascular disease can itself influence tumor growth and metastasis. Numerous epidemiological studies have reported that individuals with prevalent cardiovascular disease have an increased incidence of cancer. In parallel, studies using preclinical mouse models of myocardial infarction, heart failure, and cardiac remodeling support the notion that cardiovascular disorders accelerate the growth of solid tumors and metastases. These findings have ushered in a new and burgeoning field termed reverse cardio-oncology that investigates the impact of cardiovascular disease pathophysiology on cancer emergence and progression. Recent studies have begun to illuminate the mechanisms driving this relationship, including shared risk factors, reprogramming of immune responses, changes in gene expression, and the release of cardiac factors that result in selective advantages for tumor cells or their local milieu, thus exacerbating cancer pathology. Here, we review the evidence supporting the relationship between cardiovascular disease and cancer, the mechanistic pathways enabling this connection, and the implications of these findings for patient care.

Conjunctival microvascular alteration in patients with coronary artery disease assessed using optical coherence tomographic angiography

BACKGROUND

To quantify conjunctival microvascular characteristics obtained by optical coherence tomographic angiography (OCTA) and investigate their relationship with the presence and severity of coronary artery disease (CAD).

METHODS

This cross-sectional study included 103 consecutive CAD patients confirmed by coronary angiography and 125 non-CAD controls. The temporal conjunctivas along the limbus of each participant were scanned using OCTA. Quantification of conjunctival microvasculature was performed by AngioTool software. The severity of the disease was evaluated using SYNTAX and Gensini scores.

RESULTS

Compared to the controls, the CAD group exhibited significantly lower vessel area density (30.22 ± 3.34 vs. 26.70 ± 4.43 %, p < 0.001), lower vessel length density (6.39 ± 0.77 vs. 5.71 ± 0.89/m, p < 0.001), lower junction density (3.44 ± 0.56 vs. 3.05 ± 0.63/m, p < 0.001), and higher lacunarity (0.11 ± 0.03 vs. 0.14 ± 0.05, p < 0.001). Among all participants, lower vessel area density, lower vessel length density, lower junction density, and higher lacunarity were associated with greater odds of having CAD; the adjusted ORs (95 % confidence intervals) per one SD decrease were 2.71 (1.71, 4.29), 2.51(1.61, 3.90), 2.06 (1.39, 3.05), and 0.36 (0.23, 0.58), respectively. Among CAD patients, junction density was negatively associated with the Gensini score (r = -0.359, p = 0.037) and the Syntax score (r = -0.350, p = 0.042) in women but not in men (p > 0.05).

CONCLUSIONS

Conjunctival microvascular characteristics were significantly associated with the presence of CAD. Junction density significantly associated with the severity of CAD among women patients.

Sex Differences in Kidney Health and Disease

BACKGROUND

Sex differences exist in kidney physiology and disease which are underpinned by the biological actions of the sex hormones estrogen, progesterone and testosterone. In this review, we present an up-to-date discussion of the hormonal and molecular signalling pathways implicated in sex differences in kidney health and disease.

SUMMARY

Estrogen and progesterone have protective effects on renal blood flow, glomerular filtration rate and nephron ion and water reabsorptive processes, whereas testosterone tends to compromise these functions. The biological effects of estrogen appear to be the most important in reinforcing kidney function and protecting against kidney diseases in females. The actions of estrogen are myriad but all tend to bolster kidney physiology to maintain a steady-state and adaptable extracellular fluid volume (ECFV) and blood pressure. Estrogen safeguards ECFV homeostasis by stimulating renal epithelial sodium channel (ENaC) and water channel (AQP2) expression and transport function. Renal maintenance of ECFV within narrow physiological limits is a first-line of defense against hypertension and lowers the risk of cardiovascular disease in women. The estrogenic and XX chromosome basis for a female advantage are evident in a wide range of kidney diseases including acute kidney injury, chronic kidney disease, end-stage kidney disease, diabetic kidney disease, and polycystic kidney disease. The molecular mechanisms involve estrogen regulation of nephron ion and water transport, genetic immunogenic responses, activation of the protective arm of the renin angiotensin-aldosterone system and XX chromosome reinforcement of immune responses. Kidney disease can also predispose patients to cancer and women are protected in renal cancer with lower incidence, morbidity, and mortality than age-matched men with the disease.

KEY MESSAGES

This review underscores the importance of incorporating sex-specific considerations into clinical practice and basic research to bridge the gap in understanding and addressing biological sex disparities in kidney disease and renal cancer.

Therapeutic potential of finerenone for diabetic cardiomyopathy: focus on the mechanisms

Diabetic cardiomyopathy (DCM) is a kind of myocardial disease that occurs in diabetes patients and cannot be explained by hypertensive heart disease, coronary atherosclerotic heart disease and other heart diseases. Its pathogenesis may be closely related to programmed cell death, oxidative stress, intestinal microbes and micro-RNAs. The excessive activation of mineralocorticoid receptors (MR) in DCM can cause damage to the heart and kidneys. The third-generation non-steroidal mineralocorticoid receptor antagonist (MRA), finerenone, can effectively block MR, thus playing a role in protecting the heart and kidneys. This review mainly introduces the classification of MRA, and the mechanism of action, applications and limitations of finerenone in DCM, in order to provide reference for the study of treatment plans for DCM patients.

MicroRNA-19 is regulated by aldosterone in a sex-specific manner to alter kidney sodium transport

A key regulator of blood pressure homeostasis is the steroid hormone aldosterone, which is released as the final signaling hormone of the renin-angiotensin-aldosterone-signaling (RAAS) system. Aldosterone increases sodium (Na+) reabsorption in the kidney distal nephron to regulate blood volume. Unregulated RAAS signaling can lead to hypertension and cardiovascular disease. The serum and glucocorticoid kinase (SGK1) coordinates much of the Na+ reabsorption in the cortical collecting duct (CCD) tubular epithelial cells. We previously demonstrated that aldosterone alters the expression of microRNAs (miRs) in CCD principal cells. The aldosterone-regulated miRs can modulate Na+ transport and the cellular response to aldosterone signaling. However, the sex-specific regulation of miRs by aldosterone in the kidney distal nephron has not been explored. In this study, we report that miR-19, part of the miR-17-92 cluster, is upregulated in female mouse CCD cells in response to aldosterone activation. Mir-19 binding to the 3'-untranslated region of SGK1 was confirmed using a dual-luciferase reporter assay. Increasing miR-19 expression in CCD cells decreased SGK1 message and protein expression. Removal of this cluster using a nephron-specific, inducible knockout mouse model increased SGK1 expression in female mouse CCD cells. The miR-19-induced decrease in SGK1 protein expression reduced the response to aldosterone stimulation and may account for sex-specific differences in aldosterone signaling. By examining evolution of the miR-17-92 cluster, phylogenetic sequence analysis indicated that this cluster arose at the same time that other Na+-sparing and salt regulatory proteins, specifically SGK1, first emerged, indicating a conserved role for these miRs in kidney function of salt and water homeostasis.NEW & NOTEWORTHY Expression of the microRNA-17-92 cluster is upregulated by aldosterone in mouse cortical collecting duct principal cells, exclusively in female mice. MiR-19 in this cluster targets the serum and glucocorticoid kinase (SGK1) to downregulate both mRNA and protein expression, resulting in a decrease in sodium transport across epithelial cells of the collecting duct. The miR-17-92 cluster is evolutionarily conserved and may act as a novel feedback regulator for aldosterone signaling in females.

Sex-specific differences in risk factors, comorbidities, diagnostic challenges, optimal management, and prognostic outcomes of heart failure with preserved ejection fraction: A comprehensive literature review

Due to hormonal variations, heart failure with preserved ejection fraction (HFpEF) remains prevalent in women and affects almost half of the heart failure (HF) patients. Given the yearly death rate of 10-30% and the unavailability of medications targeting HFpEF, the need arises for a better understanding of the fundamental mechanisms of this syndrome. This comprehensive review explores sex-specific differences in traditional risk factors; female-specific factors that may impact HFpEF development and response to therapy, including variations in hormone levels that may occur pre- and post-menopausal or during pregnancy; and disparities in comorbidities, clinical presentation, and diagnostic challenges. Lastly, the review addresses prognostic outcomes, noting that women with HFpEF have a poor quality of life but a higher survival rate. It also discusses novel biomarkers and precision medicine, emphasizing their potential to improve early detection and personalized treatment.

Molecular mechanisms of endothelial dysfunction in coronary microcirculation dysfunction

Coronary microvascular endothelial cells (CMECs) react to changes in coronary blood flow and myocardial metabolites and regulate coronary blood flow by balancing vasoconstrictors-such as endothelin-1-and the vessel dilators prostaglandin, nitric oxide, and endothelium-dependent hyperpolarizing factor. Coronary microvascular endothelial cell dysfunction is caused by several cardiovascular risk factors and chronic rheumatic diseases that impact CMEC blood flow regulation, resulting in coronary microcirculation dysfunction (CMD). The mechanisms of CMEC dysfunction are not fully understood. However, the following could be important mechanisms: the overexpression and activation of nicotinamide adenine dinucleotide phosphate oxidase (Nox), and mineralocorticoid receptors; the involvement of reactive oxygen species (ROS) caused by a decreased expression of sirtuins (SIRT3/SIRT1); forkhead box O3; and a decreased SKCA/IKCA expression in the endothelium-dependent hyperpolarizing factor electrical signal pathway. In addition, p66Shc is an adapter protein that promotes oxidative stress; although there are no studies on its involvement with cardiac microvessels, it is possible it plays an important role in CMD.

Iron gets in the way

Accumulation of iron with age may inhibit the benefits of hormone replacement therapy on cardiovascular disease in late postmenopause.

Hormone replacement therapy for postmenopausal atherosclerosis is offset by late age iron deposition

Postmenopausal atherosclerosis (AS) has been attributed to estrogen deficiency. However, the beneficial effect of hormone replacement therapy (HRT) is lost in late postmenopausal women with atherogenesis. We asked whether aging-related iron accumulation affects estrogen receptor α (ERα) expression, thus explaining HRT inefficacy. A negative correlation has been observed between aging-related systemic iron deposition and ERα expression in postmenopausal AS patients. In an ovariectomized Apoe-/- mouse model, estradiol treatment had contrasting effects on ERα expression in early versus late postmenopausal mice. ERα expression was inhibited by iron treatment in cell culture and iron-overloaded mice. Combined treatment with estradiol and iron further decreased ERα expression, and the latter effect was mediated by iron-regulated E3 ligase Mdm2. In line with these observations, cellular cholesterol efflux was reduced, and endothelial homeostasis was disrupted. Consequently, AS was aggravated. Accordingly, systemic iron chelation attenuated estradiol-triggered progressive AS in late postmenopausal mice. Thus, iron and estradiol together downregulate ERα through Mdm2-mediated proteolysis, providing a potential explanation for failures of HRT in late postmenopausal subjects with aging-related iron accumulation. This study suggests that immediate HRT after menopause, along with appropriate iron chelation, might provide benefits from AS.

Female mice are protected from impaired parenchymal arteriolar TRPV4 function and impaired cognition in hypertension

Hypertension is a leading modifiable risk factor for cerebral small vessel disease. Our laboratory has shown that endothelium-dependent dilation in cerebral parenchymal arterioles (PAs) is dependent on transient receptor potential vanilloid 4 (TRPV4) activation, and this pathway is impaired in hypertension. This impaired dilation is associated with cognitive deficits and neuroinflammation. Epidemiological evidence suggests that women with midlife hypertension have an increased dementia risk that does not exist in age-matched men, though the mechanisms responsible for this are unclear. This study aimed to determine the sex differences in young, hypertensive mice to serve as a foundation for future determination of sex differences at midlife. We tested the hypothesis that young hypertensive female mice would be protected from the impaired TRPV4-mediated PA dilation and cognitive dysfunction observed in male mice. Angiotensin II (ANG II)-filled osmotic minipumps (800 ng/kg/min, 4 wk) were implanted in 16- to 19-wk-old male C56BL/6 mice. Age-matched female mice received either 800 ng/kg/min or 1,200 ng/kg/min ANG II. Sham-operated mice served as controls. Systolic blood pressure was elevated in ANG II-treated male mice and in 1,200 ng ANG II-treated female mice versus sex-matched shams. PA dilation in response to the TRPV4 agonist GSK1016790A (10-9-10-5 M) was impaired in hypertensive male mice, which was associated with cognitive dysfunction and neuroinflammation, reproducing our previous findings. Hypertensive female mice exhibited normal TRPV4-mediated PA dilation and were cognitively intact. Female mice also showed fewer signs of neuroinflammation than male mice. Determining the sex differences in cerebrovascular health in hypertension is critical for developing effective therapeutic strategies for women.NEW & NOTEWORTHY Vascular dementia is a significant public health concern, and the effect of biological sex on dementia development is not well understood. TRPV4 channels are essential regulators of cerebral parenchymal arteriolar function and cognition. Hypertension impairs TRPV4-mediated dilation and memory in male rodents. Data presented here suggest female sex protects against impaired TRPV4 dilation and cognitive dysfunction during hypertension. These data advance our understanding of the influence of biological sex on cerebrovascular health in hypertension.

Mineralocorticoid receptor antagonist treatment improved arterial stiffness in patients with primary aldosteronism: a cohort study compared with adrenalectomy

Background

Elevated arterial stiffness in patients with primary aldosteronism (PA) can be reversed after adrenalectomy; however, the effect of medical treatment with mineralocorticoid receptor antagonist (MRAs) is unknown.

Objectives

The aim of this study was to evaluate the effect of MRAs and compare both treatment strategies on arterial stiffness in PA patients.

Design

Prospective cohort study.

Methods

We prospectively enrolled PA patients from 2006 to 2019 who received either adrenalectomy or MRA treatment (spironolactone). We compared their baseline and 1-year post-treatment biochemistry characteristics and arterial pulse wave velocity (PWV) to verify the effects of treatment and related determinant factors.

Results

A total 459 PA patients were enrolled. After 1:1 propensity score matching for age, sex and blood pressure (BP), each group had 176 patients. The major determinant factors of baseline PWV were age and baseline BP. The adrenalectomy group had greater improvements in BP, serum potassium level, plasma aldosterone concentration, and aldosterone-to-renin ratio. The MRA group had a significant improvement in PWV after 1 year of treatment (1706.2 ± 340.05 to 1613.6 ± 349.51 cm/s, p < 0.001). There were no significant differences in post-treatment PWV (p = 0.173) and improvement in PWV (p = 0.579) between the adrenalectomy and MRA groups. The determinant factors for an improvement in PWV after treatment were hypertension duration, baseline PWV, and the decrease in BP.

Conclusion

The PA patients who received medical treatment with MRAs had a significant improvement in arterial stiffness. There was no significant difference in the improvement in arterial stiffness between the two treatment strategies.

Emerging vascular cell-specific roles for mineralocorticoid receptor: implications for understanding sex differences in cardiovascular disease

As growing evidence implicates extrarenal mineralocorticoid receptor (MR) in cardiovascular disease (CVD), recent studies have defined both cell- and sex-specific roles. MR is expressed in vascular smooth muscle (SMC) and endothelial cells (ECs). This review integrates published data from the past 5 years to identify novel roles for vascular MR in CVD, with a focus on understanding sex differences. Four areas are reviewed in which there is recently expanded understanding of the cell type- or sex-specific role of MR in 1) obesity-induced microvascular endothelial dysfunction, 2) vascular inflammation in atherosclerosis, 3) pulmonary hypertension, and 4) chronic kidney disease (CKD)-related CVD. The review focuses on preclinical data on each topic describing new mechanistic paradigms, cell type-specific mechanisms, sexual dimorphism if addressed, and clinical implications are then considered. New data support that MR drives vascular dysfunction induced by cardiovascular risk factors via sexually dimorphic mechanisms. In females, EC-MR contributes to obesity-induced endothelial dysfunction by regulating epithelial sodium channel expression and by inhibiting estrogen-induced nitric oxide production. In males with hyperlipidemia, EC-MR promotes large vessel inflammation by genomic regulation of leukocyte adhesion molecules, which is inhibited by the estrogen receptor. In pulmonary hypertension models, MRs in EC and SMC contribute to distinct components of disease pathologies including pulmonary vessel remodeling and RV dysfunction. Despite a female predominance in pulmonary hypertension, sex-specific roles for MR have not been explored. Vascular MR has also been directly implicated in CKD-related vascular dysfunction, independent of blood pressure. Despite these advances, sex differences in MR function remain understudied.

The Association Between Circulating Sex Hormones and Central Serous Chorioretinopathy: A Case-Control Study

Background

Central serous chorioretinopathy (CSC) is preferential cocurated in males, however the associations between sex hormones and CSC incidence or progression remains unclear. The sex hormone concentration assessments in CSC cases and healthy controls will update the knowledge in CSC management.

Methods

This case-control study included 59 CSC cases and 30 healthy controls, from January 2019 to December 2020. The CSC cases would be defined as spontaneous resolved if the subretinal fluid were absorbed within three months. The concentrations of total testosterone (TT), free testosterone (FT), estradiol (E2), sex hormone-binding globulin (SHBG), progesterone, leuteinizing hormone (LH) and dehydroepiandrosterone sulfate (DHEA-S) were detected in all the participants. The relationships between sex hormone concentrations and CSC-related characteristics were analyzed with Pearson correlation analyses.

Results

Significantly increased TT, FT, FT/E2 ratio, SHBG concentrations as well as decreased DHEA-S level were detected in non-resolved CSC group compared with the control group. Comparing with the resolved ones, it was found that TT, FT and SHBG concentrations were increased in the non-resolved CSC. A significant positive correlation between TT concentrations and CMT (R²=0.168, P=0.031) as well as SRF height (R²=0.146, P=0.045) were detected in the non-solved CSC group.

Conclusion

Different concentrations of TT, FT, FT/E2 ratio, DHEA-S and SHBG were detected in resolved and non-resolved CSC cases. Sex hormones were related to CSC symptom durations and related parameters.

Mineralocorticoid Receptor Activation in Vascular Insulin Resistance and Dysfunction

Systemic insulin resistance is characterized by reduced insulin metabolic signaling and glucose intolerance. Mineralocorticoid receptors (MRs), the principal receptors for the hormone aldosterone, play an important role in regulating renal sodium handling and blood pressure. Recent studies suggest that MRs also exist in tissues outside the kidney, including vascular endothelial cells, smooth muscle cells, fibroblasts, perivascular adipose tissue, and immune cells. Risk factors, including excessive salt intake/salt sensitivity, hypertension, and obesity, can lead to the activation of vascular MRs to promote inflammation, oxidative stress, remodeling, and fibrosis, as well as cardiovascular stiffening and microcirculatory impairment. These pathophysiological changes are associated with a diminished ability of insulin to initiate appropriate intracellular signaling events, resulting in a reduced glucose uptake within the microcirculation and related vascular insulin resistance. Therefore, the pharmacological inhibition of MR activation provides a potential therapeutic option for improving vascular function, glucose uptake, and vascular insulin sensitivity. This review highlights recent experimental and clinical data that support the contribution of abnormal MR activation to the development of vascular insulin resistance and dysfunction.

Sex-specific Association of Primary Aldosteronism With Visceral Adiposity

Context

The association between primary aldosteronism and obesity, especially its sex difference, remains unknown.

Objective

To assess the association for each subtype of primary aldosteronism with obesity parameters including visceral adipose tissue and differences between sexes.

Methods

In this case-control study, 4 normotensive controls were selected for each case with primary aldosteronism. Multivariable conditional logistic regression models were used to estimate the association between each type of primary aldosteronism and obesity indicators. We used a random forest to identify which visceral or subcutaneous tissue areas had a closer association with disease status.

Results

The study subjects included 42 aldosterone-producing adenoma cases (22 women) and 68 idiopathic hyperaldosteronism cases (42 women). In multivariable conditional logistic regressions, aldosterone-producing adenoma was significantly associated with body mass index only in men (odds ratio [OR] [95% CI)], 4.62 [1.98-10.80] per 2.89 kg/m2) but not in women (OR [95% CI], 1.09 [0.69-1.72] per 3.93 kg/m2) compared with the matched controls, whereas idiopathic hyperaldosteronism was associated with body mass index in both men (OR [95% CI], 3.96 [2.03-7.73] per 3.75 kg/m2) and women (OR [95% CI], 2.65 [1.77-3.96] per 3.85 kg/m2) compared with the matched controls. In random forests, visceral adipose tissue areas were the better predictor of both aldosterone-producing adenoma and idiopathic hyperaldosteronism than subcutaneous adipose tissue.

Conclusions

Aldosterone-producing adenoma cases were obese among men, but not among women. Idiopathic hyperaldosteronism cases were obese among both men and women. Visceral adipose tissue may contribute to the pathophysiology of primary aldosteronism.

Sex-Related Signaling of Aldosterone/Mineralocorticoid Receptor Pathway in Calcific Aortic Stenosis

BACKGROUND

There are sex differences in the pathophysiology of aortic valve (AV) calcification in patients with aortic stenosis, although the molecular and cellular mechanisms have not been elucidated. Aldosterone (Aldo) promotes proteoglycan synthesis in valve interstitial cells (VICs) from mitral valves via the mineralocorticoid receptor (MR). We investigated the influence of sex in the role of Aldo/MR pathway in AV alterations in patients with aortic stenosis.

METHODS AND RESULTS

MR was expressed by primary aortic VICs and in AVs from patients with aortic stenosis. MR expression positively correlated with VIC activation markers in AVs from both sexes. However, MR expression was positively associated with molecules involved in AV calcification only in AV from men. Aldo enhanced VIC activation markers in cells from men and women. Interestingly, Aldo increased the expression of calcification markers only in VICs isolated from men. In female VICs, Aldo enhanced fibrotic molecules. MR antagonism (spironolactone) blocked all the above effects. Cytokine arrays showed ICAM (intercellular adhesion molecule)-1 and osteopontin to be specifically increased by Aldo in male VICs. In AVs from men, MR expression positively associated with both ICAM-1 (intercellular adhesion molecule-1) and osteopontin. Only in female VICs, estradiol treatment blocked Aldo-induced VICs activation, inflammation, and fibrosis.

CONCLUSIONS

These findings demonstrate that the Aldo/MR pathway could play a role in early stages of aortic stenosis by promoting VICs activation, fibrosis, and ulterior calcification. Importantly, Aldo/MR pathway is involved in fibrosis in women and in early AV calcification only in men. Accordingly, MR antagonism emerges as a new sex-specific pharmacological treatment to prevent AV alterations.

The role of the mineralocorticoid receptor in immune cells in in cardiovascular disease

Chronic low-grade inflammation and immune cell activation are important mechanisms in the pathophysiology of cardiovascular disease (CVD). Therefore, targeted immunosuppression is a promising novel therapy to lower cardiovascular risk. In this review, we identify the mineralocorticoid receptor (MR) on immune cells as a potential target to modulate inflammation. The MR is present in almost all cells of the cardiovascular system, including immune cells. Activation of the MR in innate and adaptive immune cells induces inflammation which can contribute to CVD, by inducing endothelial dysfunction and hypertension. Moreover, it accelerates atherosclerotic plaque formation and destabilization and impairs tissue regeneration after ischemic events. Identifying the molecular targets for these non-renal actions of the MR provide promising novel cardiovascular drug targets for mineralocorticoid receptor antagonists (MRAs), which are currently mainly applied in hypertension and heart failure.

Single-cell analysis of salt-induced hypertensive mouse aortae reveals cellular heterogeneity and state changes

Elevated blood pressure caused by excessive salt intake is common and associated with cardiovascular diseases in most countries. However, the composition and responses of vascular cells in the progression of hypertension have not been systematically described. We performed single-cell RNA sequencing on the aortic arch from C57BL/6J mice fed a chow/high-salt diet. We identified 19 distinct cell populations representing 12 lineages, including smooth muscle cells (SMCs), fibroblasts, endothelial cells (ECs), B cells, and T cells. During the progression of hypertension, the proportion of three SMC subpopulations, two EC subpopulations, and T cells increased. In two EC clusters, the expression of reactive oxygen species-related enzymes, collagen and contractility genes was upregulated. Gene set enrichment analysis showed that three SMC subsets underwent endothelial-to-mesenchymal transition. We also constructed intercellular networks and found more frequent cell communication among aortic cells in hypertension and that some signaling pathways were activated during hypertension. Finally, joint public genome-wide association study data and our single-cell RNA-sequencing data showed the expression of hypertension susceptibility genes in ECs, SMCs, and fibroblasts and revealed 21 genes involved in the initiation and development of high-salt-induced hypertension. In conclusion, our data illustrate the transcriptional landscape of vascular cells in the aorta associated with hypertension and reveal dramatic changes in cell composition and intercellular communication during the progression of hypertension.

The Role of the Mineralocorticoid Receptor and Mineralocorticoid Receptor-Directed Therapies in Heart Failure

Mineralocorticoid receptor (MR) antagonists (MRA), also referred to as aldosterone blockers, are now well-recognized for their clinical benefit in patients who have heart failure (HF) with reduced ejection fraction (HFrEF). Recent studies have also shown MRA can improve outcomes in patients with HFpEF, where the ejection fraction is preserved but left ventricular filling is reduced. While the MR is a steroid hormone receptor best known for antinatriuretic actions on electrolyte homeostasis in the distal nephron, it is now established that the MR has many physiological and pathophysiological roles in the heart, vasculature, and other nonepithelial tissue types. It is the impact of MR activation on these tissues that underpins the use of MRA in cardiovascular disease, in particular HF. This mini-review will discuss the origins and the development of MRA and highlight how their use has evolved from the "potassium-sparing diuretics" spironolactone and canrenone over 60 years ago, to the more receptor-selective eplerenone and most recently the emergence of new nonsteroidal receptor antagonists esaxerenone and finerenone.

Mineralocorticoid receptors in pulmonary hypertension and right heart failure: From molecular biology to therapeutic targeting

Pulmonary hypertension (PH) is a devastating condition characterized by pulmonary vascular remodelling, leading to progressive increase in pulmonary artery pressure and subsequent right ventricular failure. Aldosterone and the mineralocorticoid receptor (MR), a nuclear transcription factor, are key drivers of cardiovascular disease and MR antagonists are well-established in heart failure. Now, a growing body of evidence points at a detrimental role of MR in PH. Pharmacological MR blockade attenuated PH and prevented RV failure in experimental models. Mouse models with cell selective MR deletion suggest that this effect is mediated by MR in endothelial cells. While the evidence from experimental studies appears convincing, the available clinical data on MR antagonist use in patients with PH is more controversial. Integrated analysis of clinical data together with MR-dependent molecular alterations may provide insights why some patients respond to MRA treatment while others do not. Potential ways to identify MRA 'responders' include the analysis of underlying PH causes, stage of disease, or sex, as well as new biomarkers.

Mineralocorticoid receptor blockade normalizes coronary resistance in obese swine independent of functional alterations in Kv channels

Impaired coronary microvascular function (e.g., reduced dilation and coronary flow reserve) predicts cardiac mortality in obesity, yet underlying mechanisms and potential therapeutic strategies remain poorly understood. Mineralocorticoid receptor (MR) antagonism improves coronary microvascular function in obese humans and animals. Whether MR blockade improves in vivo regulation of coronary flow, a process involving voltage-dependent K⁺ (K_v) channel activation, or reduces coronary structural remodeling in obesity is unclear. Thus, the goals of this investigation were to determine the effects of obesity on coronary responsiveness to reductions in arterial PO₂ and potential involvement of K_v channels and whether the benefit of MR blockade involves improved coronary K_v function or altered passive structural properties of the coronary microcirculation. Hypoxemia increased coronary blood flow similarly in lean and obese swine; however, baseline coronary vascular resistance was significantly higher in obese swine. Inhibition of K_v channels reduced coronary blood flow and augmented coronary resistance under baseline conditions in lean but not obese swine and had no impact on hypoxemic coronary vasodilation. Chronic MR inhibition in obese swine normalized baseline coronary resistance, did not influence hypoxemic coronary vasodilation, and did not restore coronary K_v function (assessed in vivo, ex vivo, and via patch clamping). Lastly, MR blockade prevented obesity-associated coronary arteriolar stiffening independent of cardiac capillary density and changes in cardiac function. These data indicate that chronic MR inhibition prevents increased coronary resistance in obesity independent of K_v channel function and is associated with mitigation of obesity-mediated coronary arteriolar stiffening.

Association of ultra-processed food consumption with cardiovascular mortality in the US population: long-term results from a large prospective multicenter study

BACKGROUND

Ultra-processed foods have now become dominant in the global food system. Whether their consumption is associated with cardiovascular mortality remains controversial. Moreover, data on ultra-processed foods and cardiovascular outcomes are scarce in the US population. We aimed to examine the association of ultra-processed food consumption with cardiovascular mortality in a US population.

METHODS

A population-based cohort of 91,891 participants was identified from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Dietary data were collected through a validated 137-item food frequency questionnaire. Ultra-processed foods were defined by the NOVA classification. Cox regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for cardiovascular mortality. Restricted cubic spline regression was used to test nonlinearity. Subgroup analyses were conducted to identify the potential effect modifiers.

RESULTS

After an average follow-up of 13.5 years (1,236,049.2 person-years), 5490 cardiovascular deaths were documented, including 3985 heart disease deaths and 1126 cerebrovascular deaths. In the fully adjusted model, participants in the highest vs. the lowest quintiles of ultra-processed food consumption had higher risks of death from cardiovascular disease (HR_{quintile 5 vs. 1}, 1.50; 95% CI, 1.36-1.64) and heart disease (HR_{quintile 5 vs. 1}, 1.68; 95% CI, 1.50-1.87) but not cerebrovascular disease (HR_{quintile 5 vs. 1}, 0.94; 95% CI, 0.76-1.17). A nonlinear dose-response pattern was observed for overall cardiovascular and heart disease mortality (all P_nonlinearity < 0.05), with a threshold effect observed at ultra-processed food consumption of 2.4 servings/day and 2.3 servings/day, respectively; below the thresholds, no significant associations were observed for these two outcomes. Subgroup analyses showed that the increased risks of mortality from ultra-processed foods were significantly higher in women than in men (all P_interaction < 0.05).

CONCLUSIONS

High consumption of ultra-processed foods is associated with increased risks of overall cardiovascular and heart disease mortality. These harmful associations may be more pronounced in women. Our findings need to be confirmed in other populations and settings.

Effect of Mineralocorticoid Receptor Blockade on Arterial Stiffness and Endothelial Function: A Meta-Analysis of Randomized Trials

Although numerous studies have confirmed the beneficial effects of pharmacological therapy for arterial stiffness and endothelial dysfunction, which are predictors/therapeutic targets for cardiovascular diseases, only a few overall quantitative evaluations of MRAs (mineralocorticoid receptor antagonists) exist. We searched PubMed and Cochrane CENTRAL (Cochrane Central Register of Controlled Trials) for randomized trials evaluating MRA effects on arterial stiffness measured by pulse wave velocity (PWV) or augmentation index and endothelial function measured by flow-mediated dilation. Data from the included trials were pooled by using random-effects meta-analysis of the weighted mean difference (MD) between the comparator groups. The primary outcome was the MD of PWV. In 11 trials including 515 patients, the MRA treatment reduced the PWV when compared with control (MD, -0.75 m/s [95% CI, -1.12 to -0.39], P<0.00001), without heterogeneity. There were comparable effects of MRA on carotid-femoral PWV and those on other forms of PWV (P=0.705 for heterogeneity). The effects of MRA on PWV were independent of blood pressure reduction related to the treatment according to meta-regression analysis. The MRA treatment reduced the augmentation index compared with control in 5 trials including 283 patients (MD, -6.74% [95% CI, -10.26 to -3.21], P=0.0002) and increased the flow-mediated dilation in 11 trials including 570 patients (MD, 1.18% [95% CI, 0.14 to 2.23], P=0.03). In conclusion, the current meta-analysis demonstrates the beneficial effects of MRA on PWV, augmentation index, and flow-mediated dilation.

Obesity and cardiovascular disease in women

As the prevalence of obesity continues to grow worldwide, the health and financial burden of obesity-related comorbidities grows too. Cardiovascular disease (CVD) is clearly associated with increased adiposity. Importantly, women are at higher risk of CVD when obese and insulin resistant, in particular at higher risk of developing heart failure with preserved ejection fraction and ischemic heart disease. Increased aldosterone and mineralocorticoid receptor activation, aberrant estrogenic signaling and elevated levels of androgens are among some of the proposed mechanisms explaining the heightened CVD risk. In addition to traditional cardiovascular risk factors, understanding nontraditional risk factors specific to women, like excess weight gain during pregnancy, preeclampsia, gestational diabetes, and menopause are central to designing personalized interventions aimed to curb the epidemic of CVD. In the present review, we examine the available evidence supporting a differential cardiovascular impact of increased adiposity in women compared with men and the proposed pathophysiological mechanisms behind these differences. We also discuss women-specific cardiovascular risk factors associated with obesity and insulin resistance.

CD38: A Potential Therapeutic Target in Cardiovascular Disease

Substantial research has demonstrated the association between cardiovascular disease and the dysregulation of intracellular calcium, ageing, reduction in nicotinamide adenine dinucleotide NAD+ content, and decrease in sirtuin activity. CD38, which comprises the soluble type, type II, and type III, is the main NADase in mammals. This molecule catalyses the production of cyclic adenosine diphosphate ribose (cADPR), nicotinic acid adenine dinucleotide phosphate (NAADP), and adenosine diphosphate ribose (ADPR), which stimulate the release of Ca²⁺, accompanied by NAD+ consumption and decreased sirtuin activity. Therefore, the relationship between cardiovascular disease and CD38 has been attracting increased attention. In this review, we summarize the structure, regulation, function, targeted drug development, and current research on CD38 in the cardiac context. More importantly, we provide original views about the as yet elusive mechanisms of CD38 action in certain cardiovascular disease models. Based on our review, we predict that CD38 may serve as a novel therapeutic target in cardiovascular disease in the future.

Regulation of ion channels in the microcirculation by mineralocorticoid receptor activation

The mineralocorticoid receptor (MR) has classically been studied in the renal epithelium for its role in regulating sodium and water balance and, subsequently, blood pressure. However, the MR also plays a critical role in the microvasculature by regulating ion channel expression and function. Activation of the MR by its endogenous agonist aldosterone results in translocation of the MR into the nucleus, where it can act as a transcription factor. Although most of the actions of the aldosterone can be attributed to its genomic activity though MR activation, it can also act by nongenomic mechanisms. Activation of this ubiquitous receptor increases the expression of epithelial sodium channels (ENaC) in both the endothelium and smooth muscle cells of peripheral and cerebral vessels. MR activation also regulates activity of calcium channels, calcium-activated potassium channels, and various transient receptor potential (TRP) channels. Modification of these ion channels results in a myriad of negative consequences, including impaired endothelium-dependent vasodilation, alterations in generation of myogenic tone, and increased inflammation and oxidative stress. Taken together, these studies demonstrate the importance of studying the impact of the MR on ion channel function in the vasculature. While research in this area has made advances in recent years, there are still many large gaps in knowledge that need to be filled. Crucial future directions of study include defining the molecular mechanisms involved in this interaction, as well as elucidating the potential sex differences that may exist, as these areas of understanding are currently lacking.

Mineralocorticoid Receptor and Endothelial Dysfunction in Hypertension

PURPOSE OF REVIEW

To review the latest reports of the contributions of the endothelial mineralocorticoid receptor to endothelial dysfunction and hypertension to begin to determine the clinical potential for this pathway for hypertension treatment.

RECENT FINDINGS

Endothelial mineralocorticoid receptor expression is sex-specifically increased in female mice and humans compared with males. Moreover, the expression of endothelial mineralocorticoid receptors is increased by endothelial progesterone receptor activation and naturally occurring fluctuations in progesterone levels (estrous, pregnancy) predict endothelial mineralocorticoid receptor expression levels in female mice. These data follow many previous reports that have indicated that endothelial mineralocorticoid receptor deletion is protective in the development of obesity- and diabetes-associated endothelial dysfunction in female mouse models. These studies have more recently been followed up by reports indicating that both intact endothelial mineralocorticoid receptor and progesterone receptor expression are required for obesity-associated, leptin-mediated endothelial dysfunction in female mice. In addition, the intra-endothelial signaling pathway for endothelial mineralocorticoid receptors to induce dysfunction requires the intact expression of α-epithelial sodium channels (αENaC) in endothelial cells in females. Endothelial mineralocorticoid receptors are sex-specifically upregulated in the vasculature of females, a sex difference which is driven by endothelial progesterone receptor activation, and increased activity of these endothelial mineralocorticoid receptors is a crucial mediator of endothelial dysfunction, and potentially hypertension, in obese female experimental models.