Contribution of aldosterone to cardiovascular and renal inflammation and fibrosis

Remodeling of the cardiac striatin interactome and its dynamics in the diabetic heart

Diabetic cardiomyopathy (DbCM) is a silent and complex condition involving numerous signaling pathways that impair cardiomyocyte metabolism and cardiac performance. Striatin (STRN) is a multifaceted protein that binds metabolic proteins, yet its role in diabetic heart remains unexplored. Here we characterized the cardiac STRN interactome by performing immunoprecipitation on left ventricle (LV) proteins from control and diabetic hearts (rats treated with streptozotocin for 24 weeks) to dissect its derivative protein complex. Diabetic rats exhibited pathological heart remodeling characterized by increased heart weight/body weight ratio, elevated levels of Atrial Natriuretic Factor (ANF), and altered expression of alpha and beta-myosin heavy chain isoforms. Notably, STRN expression mirrored that of the remodeling marker ANF across all cardiac chambers. Proteomic analysis yielded 247 proteins interacting with STRN exclusively in diabetic LV, 94 in both control and diabetic LV, and 11 only in control LV. STRN retained a higher interaction with some STRN interacting phosphatase and kinase complex (STRIPAK) proteins (i.e. protein phosphatase 2A (PP2A), and sarcolemmal associated membrane protein (SLMAP)) in diabetic LV, indicating a preserved role of this signalosome in diabetic settings. Functional enrichment and gene ontology revealed that the STRN interactome in diabetic LV carried signalosomes related to cardiac contractility, endoplasmic reticulum stress, mitochondrial function, and apoptotic processes. Western blot experiments confirmed the interaction between STRN and SLMAP in both control and diabetic heart. These data suggest a pivotal role for the STRN signalosome in cardiometabolic disorders, potentially paving the way for novel therapeutic management of DbCM. Targeting the STRN interactome in DbCM, mainly the first-line interactors SLMAP, PP2A, and Cav-1 may offer hope for patients with diabetes-induced cardiac injuries.

Canonical or non-canonical, all aspects of G protein-coupled receptor kinase 2 in heart failure

G protein-coupled receptor kinase 2 (GRK2) with its multidomain structure performs various crucial cellular functions under both normal and pathological conditions. Overexpression of GRK2 is linked to cardiovascular diseases, and its inhibition or deletion has been shown to be protective. The functions of GRK2 extend beyond G protein-coupled receptor (GPCR) signaling, influencing non-GPCR substrates as well. Increased GRK2 in heart failure (HF) initially may be protective but ultimately leads to maladaptive effects such as GPCR desensitization, insulin resistance, and apoptosis. The multifunctional nature of GRK2, including its action in hypertrophic gene expression, insulin signaling, and cardiac fibrosis, highlights its complex role in HF pathogenesis. Additionally, GRK2 is involved in mitochondrial biogenesis and lipid metabolism. GRK2 also regulates epinephrine secretion from the adrenal gland and its increase in circulating lymphocytes can be used to monitor HF status. Overall, GRK2 is a multifaceted protein with significant implications for HF and the regulation of GRK2 is crucial for understanding and treating cardiovascular diseases.

Comparison of the clinical significance of lymphocyte-based inflammatory indices between the two major subtypes of primary aldosteronism

PURPOSE

Primary aldosteronism (PA) can be classified into aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) and is related to chronic inflammatory diseases. We compared lymphocyte-based inflammatory indices among patients with APA, IHA and essential hypertension (EH), and investigated the relationships between these indices and background factors in patients with PA.

METHODS

A total of 186 patients (39 with APA, 48 with IHA, and 99 with blood-pressure-matched EH) were retrospectively included. Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) were calculated as lymphocyte-based inflammatory indices.

RESULTS

Lymphocyte count was lower in the APA group than in the IHA and EH groups. NLR and PLR were significantly higher in the APA group than in the IHA and EH groups. In the APA group, NLR correlated positively with plasma aldosterone concentration after the saline infusion test, while in the IHA group, NLR correlated positively with body mass index and negatively with flow-mediated dilation. Lymphocyte-based inflammatory indices did not differ significantly between KCNJ5-mutant and wild-type groups. NLR, MLR, and PLR remained unchanged from baseline to 1 week after adrenalectomy (ADX), but a cut-off baseline MLR of 0.18 was predictive of complete clinical success after ADX (sensitivity, 0.8095; specificity, 0.7222; area under the curve, 0.719).

CONCLUSION

Lymphocyte-based inflammatory indices showed distinct patterns in patients with APA and IHA. This study provides a better understanding of the implications of complete blood cell counts in patients with PA.

Drug Development in Pediatric Chronic Kidney Disease: A Review of Promising Treatments, Old Challenges, and New Strategies

Youth under the age of 18 years represent a distinct subset of the population living with chronic kidney disease (CKD). The etiology of CKD differs greatly between children and adults, and young people with CKD face an extended lifetime living with their disease. Few rigorous randomized controlled trials in CKD have included people under the age of 18 years. As such, the recent success of CKD trials with sodium glucose co-transporter 2 inhibitors, mineralocorticoid antagonists, dual endothelin agonists, and hypoxia-induced factor prolyl hydroxylase inhibitors have largely not extended to children and adolescents. There are many reasons to believe these medications could prove as transformative in youth as they have in older adults, but trial data are missing. Innovative strategies are required to ensure that trials of recent, and future, agents in youth with CKD are successful.

Differences in target organ damage between captopril challenge test-defined definitive-positive and borderline-range groups among patients with primary aldosteronism

The new Japanese guidelines for primary aldosteronism introduce a category in the judgment of functional confirmatory tests that is called the "borderline range," which is rare in the other international guidelines. The clinical characteristics of this borderline group are not yet understood. To investigate whether this borderline group has any significant differences in terms of target organ damage, we used data from a Japanese nationwide registry (JPAS-II) of individuals with primary aldosteronism or essential hypertension to compare the borderline group with the definitive-positive group and the negative group. We analyzed the cases of 1785 patients based on their captopril-challenge test results. Since the JPAS-II database contains plasma aldosterone concentration values obtained based on both radioimmunoassay (n = 1555) and chemiluminescent enzyme immunoassay (n = 230) principles, we converted these values to their equivalents as if measured by chemiluminescent enzyme immunoassay and conducted all analyses under the simulated condition. Multicovariate-adjusted models revealed significant prevalance odds ratios for chronic kidney disease (2.01, 95% confidence interval: 1.13 to 3.61), electrocardiographic abnormalities (1.66, 95% confidence interval: 1.16 to 2.37). No significant difference was observed between the borderline and negative groups in these assessments (odds ratio [95% confidence interval] for chronic kidney disease: 0.73 [0.26 to 2.02] and electrocardiographic abnormalities: 1.01 [0.60 to 1.70]). We confirmed that the prevalence of target organ damage increases linearly as the aldosterone-to-renin ratio rises following the captopril challenge test. These results provide material to consider regarding the significance of the provisionally established borderline group.

Involvement of Mineralocorticoid Receptor Activation by High Mobility Group Box 1 and Receptor for Advanced Glycation End Products in the Development of Acute Kidney Injury

Key Points

Our study revealed that high mobility group box 1 activates the mineralocorticoid receptor (MR) through the receptor for advanced glycation end products (RAGE) in AKI. MR antagonists and RAGE aptamers inhibited high mobility group box 1–induced Rac1/MR activation and downstream inflammatory molecules in endothelial cells. MR antagonists and RAGE aptamers may represent promising therapeutic strategies for preventing AKI and CKD progression.

Background

Although AKI is associated with an increased risk of CKD, the underlying mechanisms remain unclear. High mobility group box 1 (HMGB1), one of the ligands for the receptor for advanced glycation end products (RAGE), is elevated in patients with AKI. We recently demonstrated that the mineralocorticoid receptor (MR) is activated by the RAGE/Rac1 pathway, contributing to chronic renal damage in hypertensive mice. Therefore, this study investigated the role of the HMGB1/RAGE/MR pathway in AKI and progression to CKD.

Methods

We performed a mouse model of renal ischemia–reperfusion (I/R) with or without MR antagonist (MRA). In vitro experiments were conducted using cultured endothelial cells to examine the interaction between the HMGB1/RAGE and Rac1/MR pathways.

Results

In renal I/R injury mice, renal MR activation was associated with elevated serum HMGB1, renal RAGE, and activated Rac1, all of which were suppressed by MRA. Renal I/R injury led to renal dysfunction, tubulointerstitial injury, and increased expressions of inflammation and fibrosis mediators, which were ameliorated by MRA. In vitro , RAGE aptamer or MRA inhibited HMGB1-induced Rac1/MR activation and upregulation of monocyte chemoattractant protein 1 and NF-κB expressions. Seven days after I/R injury, renal I/R injury mice developed CKD, whereas MRA prevented renal injury progression and decreased the mortality rate. Furthermore, in case of MRA treatment even after I/R injury, attenuated renal dysfunction compared with untreated mice was also observed.

Conclusions

Our findings suggest that HMGB1 may play a crucial role in AKI and CKD development by activating the Rac1/MR pathway through interactions with RAGE.

Exploring Anti-Inflammatory Treatment as Upstream Therapy in the Management of Atrial Fibrillation

Inflammation has been widely recognized as one of the major pathophysiological drivers of the development of atrial fibrillation (AF), which works in tandem with other risk factors of AF including obesity, diabetes, hypertension, and heart failure (HF). Our current understanding of the role of inflammation in the natural history of AF remains elusive; however, several key players, including the NLRP3 (NLR family pyrin domain containing 3) inflammasome, have been acknowledged to be heavily influential on chronic inflammation in the atrial myocardium, which leads to fibrosis and eventual degradation of its electrical function. Nevertheless, our current methods of pharmacological modalities with reported immunomodulatory properties, including well-established classes of drugs e.g., drugs targeting the renin-angiotensin-aldosterone system (RAAS), statins, and vitamin D, have proven effective in reducing the overall risk of developing AF, the onset of postoperative atrial fibrillation (POAF), and reducing overall mortality among patients with AF. This might bring hope for further progress in developing new treatment modalities targeting cellular checkpoints of the NLRP3 inflammasome pathway, or revisiting other well-known anti-inflammatory drugs e.g., colchicine, vitamin C, nonsteroidal anti-inflammatory drugs (NSAIDs), glucocorticosteroids, and antimalarial drugs. In our review, we aim to find relevant upstream anti-inflammatory treatment methods for the management of AF and present the most current real-world evidence of their clinical utility.

Critical Appraisal of Pharmaceutical Therapy in Diabetic Cardiomyopathy-Challenges and Prospectives

Diabetes mellitus (DM) is a multifaceted disorder with a pandemic spread and a remarkable burden of cardiovascular mortality and morbidity. Diabetic cardiomyopathy (DBCM) has been increasingly recognized as the development of cardiac dysfunction, which is accompanied by heart failure (HF) symptoms in the absence of obvious reasons like ischemic heart disease, hypertension, or valvulopathies. Several pathophysiological mechanisms have been proposed, including metabolic disorders (e.g., glycation products), oxidative stress, low-grade inflammation, mitochondrial dysfunction, etc., which should guide the development of new therapeutic strategies. Up to now, HF treatment has not differed between patients with and without diabetes, which limits the expected benefits despite the high cardiovascular risk in the former group. However, DBCM patients may require different management, which prioritize anti-diabetic medications or testing other novel therapies. This review aims to appraise the challenges and prospectives of the individualized pharmaceutical therapy for DBCM.

Clinical implications of mineralocorticoid receptor overactivation

The mineralocorticoid receptor (MR) is a nuclear transcription factor that plays a critical role in regulating fluid, electrolytes, blood pressure, and hemodynamic stability. In conditions such as chronic kidney disease (CKD) and heart failure (HF), MR overactivation leads to increased salt and water retention, inflammatory and fibrotic gene expression, and organ injury. The MR is essential for transcriptional regulation and is implicated in metabolic, proinflammatory, and pro-fibrotic pathways. It is widely expressed in various cell types throughout the body, including the gastrointestinal tract, heart, brain, kidneys, immune cells, and vasculature. Animal studies suggest that MR activation induces oxidative stress in the kidneys and mediates renal inflammation and fibrosis. Immune cell-specific deletion of MR has shown protection against cardiac fibrosis, indicating the MR's role in pathological remodeling. In vascular smooth muscle cells, the MR regulates vascular tone and vasoconstriction. Mineralocorticoid receptor antagonists (MRAs) can be categorized based on their chemical structure as either steroidal or nonsteroidal. Steroidal MRAs (sMRA), such as spironolactone and eplerenone, have demonstrated cardiovascular benefits but are limited by hyperkalemia, gynecomastia, and sexual dysfunction. Nonsteroidal MRAs (nsMRA) have shown promise in preclinical studies and clinical trials. They offer a promising alternative by effectively blocking MR without hormone-like effects, potentially improving cardiovascular and renal disease management. Further education is necessary regarding the significance of MRA utilization in CKD and HF, balancing benefits with the risk of hyperkalemia. This risk could be mitigated by combining MRAs with potassium-binding agents. Studies are underway to explore the synergistic effects between nsMRAs and other agents, such as SGLT-2i inhibitors and Glucagon-like peptide-1 agonists, to optimize cardiorenal outcomes. Overall, MR overactivation remains a significant therapeutic target, with nsMRAs showing promise as pivotal therapies in CKD and HF management. This review highlights the evolving landscape of MR-targeted therapies, their molecular mechanisms, and clinical implications in cardiorenal diseases.

Association between mineralocorticoid receptor antagonists and kidney harm: A systematic review and meta-analysis of randomized controlled trials

Conflicting data have been reported on the association between mineralocorticoid receptor antagonists (MRAs) and acute kidney injury (AKI). This systematic review and meta-analysis aimed to evaluate whether MRAs affect the risk of AKI. MEDLINE via PubMed, the Cochrane Central Register of Controlled Trials, and the ClinicalTrials.gov website were comprehensively searched to extract all relevant studies. Randomized controlled trials (RCTs) were selected that compared MRA versus placebo or no treatment and had study populations consisting of patients with heart or kidney disease. The primary outcome was AKI. The secondary outcome was kidney injury, including AKI and non-AKI. Thirty-three studies were included in the meta-analysis. MRAs were not associated with an increased risk of AKI (risk ratio [RR] 1.13, 95% confidence interval [CI] 0.88-1.46, p = 0.29, I2 = 15%, 18,065 patients, 13 RCTs, moderate certainty). For the secondary outcome, MRAs were associated with an increased risk of kidney injury (RR 1.52, 95% CI 1.24-1.87, p < 0.01, I2 = 48%, 27,492 patients, 33 RCTs, low certainty). In particular, only canrenone (RR 5.39, 95% CI 2.17-13.37, p < 0.01) and spironolactone (RR 1.78, 95% CI 1.48-2.14, p < 0.01) were associated with an increased risk of kidney injury. However, eplerenone and finerenone seem not to increase the risk of kidney injury in patients with heart or kidney disease. The selection of MRAs might influence the risk of kidney-associated events. Further studies focusing on individual MRAs may be needed to clarify these differences.

The effect of adrenalectomy on bleomycin-induced pulmonary fibrosis in mice

Progressive lung fibrosis is often fatal and has limited treatment options. Though the mechanisms are poorly understood, fibrosis is increasingly linked with catecholamines such as adrenaline (AD) and noradrenaline (NA) and hormones such as aldosterone (ALD). The essential functions of the adrenal glands include the production of catecholamines and numerous hormones, but the contribution of adrenal glands to lung fibrosis remains less well studied. Here, we characterized the impact of surgical adrenal ablation in the bleomycin model of lung fibrosis. Wild-type mice underwent surgical adrenalectomy or sham surgery followed by bleomycin administration. We found that although bleomycin-induced collagen overdeposition in the lung was not affected by adrenalectomy, histologic indices of lung remodeling were ameliorated. These findings were accompanied by a decrease of lymphocytes in bronchoalveolar lavage (BAL) and macrophages in lung tissues, along with concomitant reductions in alpha-smooth muscle actin (αSMA) and fibronectin. Surgical adrenalectomy completely abrogated AD, not NA, detection in all compartments. Systemic ALD levels were reduced after adrenalectomy, whereas ALD levels in lung tissues remained unaffected. Taken together, these results support the presence of a pulmonary-adrenal axis in lung fibrosis and suggest that adrenalectomy is protective in this disease. Further investigation will be needed to better understand this observation and aid in the development of novel therapeutic strategies.NEW & NOTEWORTHY The lung-adrenal axis plays a significant role in pulmonary fibrosis. Adrenalectomy provides protection against lung fibrotic ECM remodeling and lung inflammation by reducing the levels of lymphocytes in BAL and macrophages in lung of bleomycin-treated mice. Although compared with sham surgery, adrenalectomy raised collagen concentration in uninjured mice, there was no discernible difference in bleomycin-induced collagen accumulation. However, adrenalectomy significantly reversed the enhanced expression and colocalization of αSMA and fibronectin induced by bleomycin.

Mineralocorticoid receptor antagonists and heart failure with preserved ejection fraction: current understanding and future prospects

The mineralocorticoid receptor (MR), part of the steroid hormone receptor subfamily within nuclear hormone receptors, is found in the kidney and various non-epithelial tissues, including the heart and blood vessels. When improperly activated, it can contribute to heart failure processes such as cardiac hypertrophy, fibrosis, stiffening of arteries, inflammation, and oxidative stress. MR antagonists (MRAs) have shown clear clinical benefits in patients with heart failure with reduced ejection fraction (HFrEF). However, in cases of heart failure with preserved ejection fraction (HFpEF), there is considerable diversity due to its complex underlying mechanisms, resulting in conflicting findings regarding the effectiveness of MRAs in relevant studies. The concept of phenomapping presents an encouraging avenue for investigating different intervention targets and novel therapies for HFpEF. Post hoc analysis of the TOPCAT trial identified certain HFpEF phenotypes that responded favorably to spironolactone. Growing clinical and preclinical evidence suggests that non-steroidal MRAs, which exhibit greater receptor selectivity, stronger anti-fibrotic and anti-inflammatory properties, and fewer hormone-related side effects, may emerge as another promising treatment option for HFpEF alongside sodium-glucose co-transporter 2 (SGLT2) inhibitors. This review aims to outline the structural and functional characteristics of MR, discuss the physiological effects of its activation and inhibition, and delve into the potential for personalized MRA therapy based on the concept of HFpEF phenotype.

Recent Advances and Perspectives on the Use of Mineralocorticoid Receptor Antagonists for the Treatment of Hypertension and Chronic Kidney Disease: A Review

Chronic kidney disease (CKD) is a major public health concern around the world. It is a significant risk factor for cardiovascular disease (CVD), and, as it progresses, the risk of cardiovascular events increases. Furthermore, end-stage kidney disease severely affects life expectancy and quality of life. Type 2 diabetes and hypertension are not only primary causes of CKD but also independent risk factors for CVD, which underscores the importance of effective treatment strategies for these conditions. The current therapies, including angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and sodium-glucose co-transporter 2 inhibitors, are administered to control hypertension, slow the progression of CKD, and reduce cardiovascular risk. However, their efficacy remains suboptimal in certain instances. Mineralocorticoid receptor (MR), a nuclear receptor found in various tissues, such as the kidney and heart, plays a pivotal role in the progression of CKD. Overactivation of MR triggers inflammation and fibrosis, which exacerbates kidney damage and accelerates disease progression. MR antagonists (MRAs) have substantial beneficial effects in patients with cardiac and renal conditions; however, their use has been constrained because of adverse effects, such as hyperkalemia and kidney dysfunction. Recently, novel non-steroidal MRAs are more efficacious and have superior safety profiles to steroidal MRAs, making them promising potential components of future treatment strategies. Here, we discuss recent findings and the roles of MRAs in the management of hypertension and CKD, with a focus on the evidence obtained from fundamental research and major clinical trials.

The Effects of Aldosterone on Hypertension-Associated Kidney Injury in a Tg-hAS Mouse Model

Hypertension remains a global health challenge due to its high prevalence and association with premature morbidity and mortality. Aldosterone, a mineralocorticoid hormone, and its receptor, the mineralocorticoid receptor (MR), are highly implicated in hypertension pathogenesis. Aldosterone synthase is the sole enzyme responsible for producing aldosterone in humans. We established transgenic mice carrying the human aldosterone synthase gene (cyp11B2) and showed dramatically increased levels of aldosterone in female hemizygotes. High-salt diets persistently increased blood pressure in these mice, and salt-induced hypertension was significantly ameliorated by reducing aldosterone levels via an aldosterone synthase inhibitor or blocking MR via an MR inhibitor. Since both hypertension and hyperaldosteronism specifically induce chronic kidney disease, in this model, we demonstrated that chronic high-salt diets induced hypertension in this mouse line and resulted in kidney inflammation and injury. Both the aldosterone synthase inhibitor and the MR antagonist markedly blocked high-salt-diet-mediated kidney injury. Thus, this transgenic mouse line can be used to study the pathogenic mechanisms underlying aldosterone and its receptor and to screen therapeutic compounds for aldosterone-mediated hypertension and related complications, such as kidney disease, in humans.

Aldosterone and Potassium in Heart Failure: Overcoming This Major Impediment in Clinical Practice

Aldosterone is a key regulator of fluid and electrolyte balance in the body. It is often dysregulated in heart failure (HF) and is a key driver of cardiac remodelling and worse clinical outcomes. Potassium regulation is essential for normal cardiac, gastrointestinal and neuromuscular function. Serum potassium fluctuations are largely determined by aldosterone, the final step of the renin-angiotensin-aldosterone system. Dyskalaemia (i.e. hypokalaemia and hyperkalaemia) is prevalent in HF because of the disease itself, its therapies and related comorbidities such as chronic kidney disease. Prognostic implications of abnormal serum potassium follow a U-shaped curve, where both hypokalaemia and hyperkalaemia are associated with adverse outcomes. Hypokalaemia is associated with increased mortality, starting from potassium <4.0 mmol/l but especially at potassium <3.5 mmol/l. Hyperkalaemia, along with increasing arrhythmia risk, limits the use of lifesaving renin-angiotensin- aldosterone system inhibitors, which may have long-term survival implications. The advent of novel potassium binders aims to manage chronic hyperkalaemia and may allow for uptitration and optimal dosing of guideline-recommended therapy. This review discusses the impacts of dyskalaemia in HF, along with management strategies, including the relevance of potassium binder use in optimising HF treatment. Current and potential future aldosterone-modulating therapies, such as non-steroidal mineralocorticoid receptor antagonists and aldosterone synthase inhibitors, are also discussed.

Mineralocorticoid Receptor and Aldosterone: Interaction Between NR3C2 Genetic Variants, Sex, and Age in a Mixed Cohort

CONTEXT

Hypertension, a prevalent cardiovascular risk, often involves dysregulated aldosterone and its interaction with the mineralocorticoid receptor (MR). Experimental designs in animal models and human cohorts have demonstrated a sex and age dependency of aldosterone secretion that expands our pathophysiologic understanding.

OBJECTIVE

This study explores the genetic variation of NR3C2, which encodes MR, in relation to aldosterone, considering age, sex, and race.

METHODS

Incorporating 720 Caucasians and 145 Africans from the HyperPATH cohort, we investigated the impact of rs4835490, a single nucleotide risk allele variant, on aldosterone levels and vasculature.

RESULTS

Notably, a significant association between rs4835490 and plasma aldosterone under liberal salt conditions emerged in individuals of European ancestry (P = .0002). Homozygous carriers of the risk A allele exhibited elevated plasma aldosterone levels (AA = 8.1 ± .9 vs GG = 4.9 ± .5 ng/dL). Additionally, aldosterone activation through posture (P = .025) and urinary excretion (P = .0122) showed notable associations. Moreover, genetic interactions with race, sex, and age were observed. Caucasian females under 50 years displayed higher plasma aldosterone, urine aldosterone, and posture aldosterone with the AA genotype compared to females over 50 years, suggesting a potential connection with menopausal or estrogen influences. Interestingly, such age-dependent interactions were absent in the African cohort.

CONCLUSION

Our study highlights the significance of the NR3C2 genetic variation and its interplay with age, sex, and race in aldosterone activation. The findings point toward an estrogen-modulating effect on MR activation, particularly in women, underlining the role of aldosterone dysregulation in hypertension development. This insight advances our comprehension of hypertension's complexities and opens avenues for personalized interventions. Clinical Trial Registration Number: NCT03029806 (registered January 24, 2017).

Serum symmetric dimethylarginine concentrations in enalapril- or telmisartan-treated dogs with proteinuric chronic kidney disease

Introduction

Renin-angiotensin-aldosterone system inhibition (RAASi) reduces intraglomerular pressure and is a standard therapy for dogs with proteinuric chronic kidney disease (CKD). RAASi can acutely decrease glomerular filtration rate (GFR); however, its effects on the marker of GFR serum symmetric dimethylarginine (SDMA) concentration in dogs have not been specifically evaluated. The objective of this study was to evaluate changes, relative to pretreatment values, in serum SDMA concentrations in dogs with proteinuric CKD receiving RAASi therapy.

Methods

This retrospective study used banked samples from 29 dogs with proteinuric CKD treated with enalapril (0.5 mg/kg PO q12h; n = 16) or telmisartan (1 mg/kg PO q24h; n = 13) alone (n = 22) or in combination with amlodipine if severely hypertensive (n = 7). Serum SDMA, creatinine, and urea nitrogen (SUN) concentrations were measured before and 7 and 30 days after starting RAASi. Percentage and absolute changes in these biomarkers were calculated for each dog and time point. A linear mixed model was used to test whether changes significantly differed from zero (α < 0.05).

Results

Overall, mean ± SEM Day 7 and 30 percentage change in SDMA were  - 4.8 ± 3.6% and  - 3.2 ± 3.4%, respectively; in creatinine were 7.4 ± 3.3% and 3.0 ± 3.1%, respectively; and in SUN were 22.1 ± 6.8% and 16.7 ± 6.2%, respectively. Mean changes varied according to whether all dogs, those on RAASi alone, or those co-treated with amlodipine were evaluated. In dogs receiving RAASi alone, at day 7, there were significant mean percentual increases in creatinine (9%; p = 0.023) and SUN (23%; p = 0.005), but SDMA was unchanged. In dogs co-treated with amlodipine, a significant absolute decrease in mean SDMA (-2.29 μg/dL; p = 0.026) occurred at days 7 and 30, while mean creatinine was unchanged and mean SUN increased.

Discussion

Proteinuric dogs receiving RAASi had low-magnitude changes in serum SDMA and creatinine, and moderate-magnitude changes in SUN concentrations. The direction of change in SDMA did not consistently match that of creatinine and SUN.

Aldosterone Synthase Inhibitors for Cardiorenal Protection: Ready for Prime Time?

BACKGROUND

Aldosterone is the principal mineralocorticoid hormone and the final effector of the renin-angiotensin-aldosterone system. This hormone is primarily synthesized by the CYP11B2 enzyme and produced by the adrenal zona glomerulosa. Through genomic and non-genomic effects, it plays an important role in cardiovascular and renal disease. To counteract aldosterone-mediated damage, steroidal mineralocorticoid receptor antagonists are recommended by international guidelines, but endocrine side effects often limit their use in a substantial proportion of patients. Conversely, nonsteroidal mineralocorticoid receptor antagonists, with an improved selectivity and safety profile, are gaining a prominent position among therapeutic pillars. However, blocking the mineralocorticoid receptors does not completely inhibit aldosterone effects because of escape mechanisms and non-genomic activity. Thus, inhibiting aldosterone synthesis could be a promising strategy to prevent aldosterone-mediated cardiorenal damage. The limited specificity for CYP11B2 and side effects due to off-target activity hampered the development of first-generation aldosterone synthase inhibitors (ASIs).

SUMMARY

The development of highly specific ASIs led to successful clinical trials in patients with resistant and uncontrolled hypertension. Additionally, a recent randomized clinical trial showed a significant benefit of ASIs in patients with chronic kidney disease and albuminuria.

KEY MESSAGES

The strength of the clinical evidence collected so far is still limited, and larger outcome-based clinical trials are needed to confirm the promising role of ASIs in cardiorenal damage.

Emerging insights into the pathogenesis and therapeutic strategies for vascular endothelial injury-associated diseases: focus on mitochondrial dysfunction

As a vital component of blood vessels, endothelial cells play a key role in maintaining overall physiological function by residing between circulating blood and semi-solid tissue. Various stress stimuli can induce endothelial injury, leading to the onset of corresponding diseases in the body. In recent years, the importance of mitochondria in vascular endothelial injury has become increasingly apparent. Mitochondria, as the primary site of cellular aerobic respiration and the organelle for "energy information transfer," can detect endothelial cell damage by integrating and receiving various external stress signals. The generation of reactive oxygen species (ROS) and mitochondrial dysfunction often determine the evolution of endothelial cell injury towards necrosis or apoptosis. Therefore, mitochondria are closely associated with endothelial cell function, helping to determine the progression of clinical diseases. This article comprehensively reviews the interconnection and pathogenesis of mitochondrial-induced vascular endothelial cell injury in cardiovascular diseases, renal diseases, pulmonary-related diseases, cerebrovascular diseases, and microvascular diseases associated with diabetes. Corresponding therapeutic approaches are also provided. Additionally, strategies for using clinical drugs to treat vascular endothelial injury-based diseases are discussed, aiming to offer new insights and treatment options for the clinical diagnosis of related vascular injuries.

Aldosterone in the brain and cognition: knowns and unknowns

Mineralocorticoid receptors are expressed in several structures of the central nervous system, and aldosterone levels can be measured in the brain, although in smaller amounts than in plasma. Nevertheless, these amounts appear to be sufficient to elicit substantial clinical effects. Primary aldosteronism, characterized by high levels of plasma aldosterone, is one of the most common causes of secondary hypertension. In this context, high aldosterone levels may have both indirect and direct effects on the brain with a negative impact on several cerebral functions. Thus, chronic aldosterone excess has been associated with symptoms of anxiety and depression - two clinical entities themselves associated with cognitive deficits. Today, there is an increasing number of reports on the influence of aldosterone on the brain, but there is also a significant amount of uncertainty, such as the role of high aldosterone levels on cognitive functions and decline independently of blood pressure. In this mini review, we discuss the known and unknowns of the impact of aldosterone on the brain putting emphasis on cognitive functions.

Prognostic Predictors of Hypertension Outcomes After Adrenalectomy in Primary Aldosteronism

BACKGROUND/AIM

Hypertension does not always improve after adrenalectomy for primary aldosteronism (PA), and antihypertensive medications cannot always be discontinued. This study aimed to identify the prognostic predictors of hypertension following adrenalectomy for PA.

PATIENTS AND METHODS

This retrospective cohort study included patients undergoing adrenalectomy for PA between 2008 and 2022 at a tertiary hospital, grouping them based on whether they had normal blood pressure without antihypertensive medications or still required medications postoperatively. Age, sex, body mass index (BMI), biochemical data, hypertension duration, pre- and post-operative defined daily dose (DDD) of antihypertensive drugs, presence of metabolic syndrome (MetS)-related diseases, and visceral fat area and volume (recorded using preoperative abdominal computed tomography) were the outcome measures.

RESULTS

A total of 71 (clinical success, n=21) (nonclinical success, n=50) patients were included. A high BMI (p=0.038), DDD (p=0.008), and visceral fat volume (p=0.048); long hypertension duration (p=0.034); and the presence of MetS-related diseases (p=0.014) were associated with a low clinical success rate on univariate analyses. After adjusting for age and sex, hypertension duration (p=0.047), MetS-related diseases (p=0.021), and DDD (p=0.011) were potential prognostic predictors.

CONCLUSION

Hypertension duration, MetS-related diseases, and DDD are potential prognostic predictors of hypertension following surgery for PA.

Stroke-Induced Renal Dysfunction: Underlying Mechanisms and Challenges of the Brain-Kidney Axis

Stroke, a major neurological disorder and a leading cause of disability and death, often inflicts damage upon other organs, particularly the kidneys. While chronic kidney disease (CKD) has long been established as a significant risk factor for cerebrovascular disease, stroke can induce renal dysfunction, manifesting as acute kidney injury (AKI) or CKD. Mounting clinical and basic research evidence supports the existence of a bidirectional brain-kidney crosstalk following stroke, implicating specific mechanisms and pathways in stroke-related renal dysfunction. This review analyzes pertinent experimental studies, elucidating the underlying mechanisms of this cerebro-renal interaction following stroke. Additionally, we summarize the current landscape of clinical research investigating brain-kidney interplay and discuss potential challenges in the future. By enhancing our understanding of the scientific underpinnings of brain-kidney crosstalk, this review paves the way for improved treatment strategies and outcomes for stroke patients. Recognizing the intricate interplay between the brain and kidneys after stroke holds profound clinical implications.

Mineralocorticoid Receptor Blocker Prevents Mineralocorticoid Receptor-Mediated Inflammation by Modulating Transcriptional Activity of Mineralocorticoid Receptor-p65-Signal Transducer and Activator of Transcription 3 Complex

BACKGROUND

Mineralocorticoid receptor (MR) induces cardiac inflammation cooperatively with nuclear factor-κB and signal transducer and activator of transcription 3 (STAT3); MR blockers exert anti-inflammatory effects. However, the underlying mechanism remains unclear. We investigated the anti-inflammatory effect of esaxerenone, a novel MR blocker, in experimental myocardial infarction (MI) and its underlying mechanisms.

METHODS AND RESULTS

Male C57BL/6J mice subjected to ligation of the left anterior descending artery were randomly assigned to either the vehicle or esaxerenone group. Esaxerenone was provided with a regular chow diet. The mice were euthanized at either 4 or 15 days after MI. Cardiac function, fibrosis, and inflammation were evaluated. Esaxerenone significantly improved cardiac function and attenuated cardiac fibrosis at 15 days after MI independently of its antihypertensive effect. Inflammatory cell infiltration, inflammatory-related gene expression, and elevated serum interleukin-6 levels at 4 days after MI were significantly attenuated by esaxerenone. In vitro experiments using mouse macrophage-like cell line RAW264.7 cells demonstrated that esaxerenone- and spironolactone-attenuated lipopolysaccharide-induced interleukin-6 expression without altering the posttranslational modification and nuclear translocation of p65 and STAT3. Immunoprecipitation assays revealed that MR interacted with both p65 and STAT3 and enhanced the p65-STAT3 interaction, leading to a subsequent increase in interleukin-6 promoter activity, which was reversed by esaxerenone.

CONCLUSIONS

Esaxerenone ameliorated postinfarct remodeling in experimental MI through its anti-inflammatory properties exerted by modulating the transcriptional activity of the MR-p65-STAT3 complex. These results suggest that the MR-p65-STAT3 complex can be a novel therapeutic target for treating MI.

Effects of mineralocorticoid receptor antagonists on new-onset or recurrent atrial fibrillation: a Bayesian and frequentist network meta-analysis of randomized trials

Background Clinical and translational research suggests that mineralocorticoid receptor antagonists (MRAs) may prevent atrial fibrosis and electrical remodeling associated with atrial fibrillation (AF). This study aimed to consolidate existing evidence from randomized controlled trials (RCTs) evaluating the effect of MRAs on incident or recurrent AF. Methods Medline, Cochrane Library and Scopus were searched until February 12, 2024. Triple-independent study selection, data extraction and quality assessment were performed. Evidence was pooled using both pairwise and Bayesian and frequentist network meta-analyses. Results Twenty-three RCTs (13,358 participants) were identified. Based on the pairwise random effects meta-analysis, MRAs were associated with a significant reduction in AF events compared to placebo or usual care (risk ratio {RR}= 0.75; 95% confidence interval {CI}= [0.66, 0.87]; P< 0.001; I2= 3%). This protective effect was robust both for new-onset and recurrent AF episodes (subgroup p-value= 0.69), while the baseline HF status was not a significant effect modifier (subgroup p-value= 0.58). MRAs demonstrated a significantly higher reduction in AF events for patients with chronic renal disease compared to placebo (RR= 0.78; 95% CI= [0.62, 0.98]; P= 0.03; I2= 0%). The network meta-analyses revealed that only spironolactone was associated with a significant reduction in AF events (Bayesian RR= 0.76; 95% CI= [0.65, 0.89]; P< 0.001; level of evidence moderate; SUCRA 0.731), while eplerenone and finerenone showed a neutral effect. Conclusion MRAs confer a significant benefit in terms of reducing incident or recurrent AF episodes, irrespective of HF status. In this context, spironolactone may be preferable compared to eplerenone or finerenone.

A Multivariable Mendelian Randomization Study of Systolic and Diastolic Blood Pressure, Lipid Profile, and Heart Failure Subtypes

Heart failure (HF) is a significant health burden, with two major clinical subtypes: HF with reduced (HFrEF) and preserved ejection fraction (HFpEF). Blood pressure and lipid profile are established risk factors of HF. We performed univariable and multivariable Mendelian randomization (MR) analyses to assess potential causal effects of blood pressures and lipids on HF subtypes. Genetic instruments for blood pressures and lipids were derived from genome-wide association studies (GWASs) among the European participants of the UK Biobank. GWAS summaries of HFrEF and HFpEF were obtained from the meta-analysis of the European participants from the Million Veteran Program and the Vanderbilt University DNA Databank. Systolic blood pressure exhibited a supportive MR association primarily with HFpEF (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.04-1.23), while diastolic blood pressure had an independent MR association with HFrEF (OR, 1.43; 95% CI, 1.13-1.77). MR associations also supported the observation that higher levels of low-density lipoprotein cholesterol increase the risk for both subtypes (HFrEF OR, 1.10 and 95% CI, 1.05-1.17; HFpEF OR, 1.05 and 95% CI, 1.02-1.09). These findings underscore differences in HF subtype-specific risk profiles and mechanisms, which may lead to different interventional strategies for different HF subtypes.

Decoding the role of aldosterone in glycation-induced diabetic complications

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

Obesity: the perfect storm for heart failure

Obesity condition causes morphological and functional alterations involving the cardiovascular system. These can represent the substrates for different cardiovascular diseases, such as atrial fibrillation, coronary artery disease, sudden cardiac death, and heart failure (HF) with both preserved ejection fraction (EF) and reduced EF. Different pathogenetic mechanisms may help to explain the association between obesity and HF including left ventricular remodelling and epicardial fat accumulation, endothelial dysfunction, and coronary microvascular dysfunction. Multi-imaging modalities are required for appropriate recognition of subclinical systolic dysfunction typically associated with obesity, with echocardiography being the most cost-effective technique. Therapeutic approach in patients with obesity and HF is challenging, particularly regarding patients with preserved EF in which few strategies with high level of evidence are available. Weight loss is of extreme importance in patients with obesity and HF, being a primary therapeutic intervention. Sodium-glucose co-transporter-2 inhibitors have been recently introduced as a novel tool in the management of HF patients. The present review aims at analysing the most recent studies supporting pathogenesis, diagnosis, and management in patients with obesity and HF.

Esaxerenone: blood pressure reduction and cardiorenal protection without reflex sympathetic activation in salt-loaded stroke-prone spontaneously hypertensive rats

Mineralocorticoid receptor (MR) is involved in the mechanisms of blood pressure elevation, organ fibrosis, and inflammation. MR antagonists have been used in patients with hypertension, heart failure, or chronic kidney disease. Esaxerenone, a recently approved MR blocker with a nonsteroidal structure, has demonstrated a strong blood pressure-lowering effect. However, blood pressure reduction may lead to sympathetic activation through the baroreflex. The effect of esaxerenone on the sympathetic nervous system remains unclear. We investigated the effect of esaxerenone on organ damage and the sympathetic nervous system in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP), a well-established model of essential hypertension with sympathoexcitation and organ damage. Three-week administration of esaxerenone or hydralazine successfully attenuated the blood pressure elevation. Both esaxerenone and hydralazine comparably suppressed left ventricular hypertrophy and urinary albumin excretion. However, renal fibrosis and glomerular sclerosis were suppressed by esaxerenone but not hydralazine. Furthermore, plasma norepinephrine level, a parameter of systemic sympathetic activity, was significantly increased by hydralazine but not by esaxerenone. Consistent with these findings, the activity of the control centers of sympathetic nervous system, the parvocellular region of the paraventricular nucleus in the hypothalamus and the rostral ventrolateral medulla, was enhanced by hydralazine but remained unaffected by esaxerenone. These results suggest that esaxerenone effectively lowers blood pressure without inducing reflex sympathetic nervous system activation. Moreover, the organ-protective effects of esaxerenone appear to be partially independent of its blood pressure-lowering effect. In conclusion, esaxerenone demonstrates a blood pressure-lowering effect without concurrent sympathetic activation and exerts organ-protective effects in salt-loaded SHRSP. Esaxerenone has antihypertensive and cardiorenal protective effects without reflex sympathetic activation in salt-loaded stroke-prone spontaneously hypertensive rats.

The current landscape of antifibrotic therapy across different organs: A systematic approach

Fibrosis is a common pathological process that can affect virtually all the organs, but there are hardly any effective therapeutic options. This has led to an intense search for antifibrotic therapies over the last decades, with a great number of clinical assays currently underway. We have systematically reviewed all current and recently finished clinical trials involved in the development of new antifibrotic drugs, and the preclinical studies analyzing the relevance of each of these pharmacological strategies in fibrotic processes affecting tissues beyond those being clinically studied. We analyze and discuss this information with the aim of determining the most promising options and the feasibility of extending their therapeutic value as antifibrotic agents to other fibrotic conditions.

Strategies to address diabetic kidney disease burden in Mexico: a narrative review by the Mexican College of Nephrologists

Chronic kidney disease (CKD) is a growing global public health challenge worldwide. In Mexico, CKD prevalence is alarmingly high and remains a leading cause of morbidity and mortality. Diabetic kidney disease (DKD), a severe complication of diabetes, is a leading determinant of CKD. The escalating diabetes prevalence and the complex regional landscape in Mexico underscore the pressing need for tailored strategies to reduce the burden of CKD. This narrative review, endorsed by the Mexican College of Nephrologists, aims to provide a brief overview and specific strategies for healthcare providers regarding preventing, screening, and treating CKD in patients living with diabetes in all care settings. The key topics covered in this review include the main cardiometabolic contributors of DKD (overweight/obesity, hyperglycemia, arterial hypertension, and dyslipidemia), the identification of kidney-related damage markers, and the benefit of novel pharmacological approaches based on Sodium-Glucose Co-Transporter-2 Inhibitors (SGLT2i) and Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RA). We also address the potential use of novel therapies based on Mineralocorticoid Receptor Antagonists (MRAs) and their future implications. Emphasizing the importance of multidisciplinary treatment, this narrative review aims to promote strategies that may be useful to alleviate the burden of DKD and its associated complications. It underscores the critical role of healthcare providers and advocates for collaborative efforts to enhance the quality of life for millions of patients affected by DKD.

Angiotensin receptor blocker-neprilysin inhibitor for heart failure with reduced ejection fraction

Heart failure with reduced ejection fraction (HFrEF) is a clinical syndrome characterized by volume overload, impaired exercise capacity, and recurrent hospital admissions. A major contributor to the pathophysiology and clinical presentation of heart failure is the activation of the renin-angiotensin-aldosterone system (RAAS). Normally, RAAS is responsible for the homeostatic regulation of blood pressure, extracellular fluid volume, and serum sodium concentration. In HFrEF, RAAS gets chronically activated in response to decreased cardiac output, further aggravating the congestion and cardiotoxic effects. Hence, inhibition of RAAS is a major approach in the pharmacologic treatment of those patients. The most recently introduced RAAS antagonizing medication class is angiotensin receptor blocker/ neprilysin inhibitor (ARNI). In this paper, we discuss ARNIs' superiority over traditional RAAS antagonizing agents in reducing heart failure hospitalization and mortality. We also tease out the evidence that shows ARNIs' renoprotective functions in heart failure patients including those with chronic or end stage kidney disease. We also discuss the evidence showing the added benefit resulting from combining ARNIs with a sodium-glucose cotransporter-2 (SGLT-2) inhibitor. Moreover, how ARNIs decrease the risk of arrhythmias and reverse cardiac remodeling, ultimately lowering the risk of cardiovascular death, is also discussed. We then present the positive outcome of ARNIs' use in patients with diabetes mellitus and those recovering from acute decompensated heart failure. ARNIs' side effects are also appreciated and discussed. Taken together, the provided insight and critical appraisal of the evidence justifies and supports the implementation of ARNIs in the guidelines for the treatment of HFrEF.

Effect of Spironolactone on Kidney Function in Kidney Transplant Recipients (the SPIREN trial): A Randomized Placebo-Controlled Clinical Trial

Key Points

Spironolactone is safe for kidney transplant patients. Spironolactone reduces kidney function by an acute effect, whereafter it remains stable. Spironolactone does not affect the progression of interstitial fibrosis in protocol biopsies.

Background

Long-term kidney allograft survival is hampered by progressive interstitial fibrosis and tubular atrophy. The SPIREN trial tested the hypothesis that the mineralocorticoid receptor antagonist spironolactone stabilizes kidney function and attenuates glomerular barrier injury in kidney transplant patients treated with calcineurin inhibitors.

Methods

We conducted a randomized, placebo-controlled, double-blind clinical trial including 188 prevalent kidney transplant patients. Patients were randomized to spironolactone or placebo for 3 years. GFR was measured along with proteinuria and kidney fibrosis. The primary end point was change in measured GFR. Secondary outcomes were 24-hour proteinuria, kidney allograft fibrosis, and cardiovascular events. Measured GFRs, 24-hour proteinuria, and BP were determined yearly. Kidney biopsies were collected at baseline and after 2 years (n =48). Fibrosis was evaluated by quantitative stereology and classified according to Banff.

Results

The groups were comparable at baseline except for slightly older allografts in the spironolactone group. Spironolactone reduced measured GFRs (up to –7.6 [95% confidence interval, −10.9 to −4.3] ml/min compared with placebo) independently of time since transplantation and BP with no effect on the kidney function curve over time and reduced 24-hour proteinuria after 1 year. There was no significant effect of spironolactone on the development of interstitial fibrosis.

Conclusions

Spironolactone added to standard therapy for 3 years in kidney transplant patients did not improve kidney function, long-term proteinuria, or interstitial fibrosis.

Clinical Trial registration number

NCT01602861 .

Challenging and target-based shifting strategies for heart failure treatment: An update from the last decades

Heart failure (HF) is a major global health problem afflicting millions worldwide. Despite the significant advances in therapies and prevention, HF still carries very high morbidity and mortality, requiring enormous healthcare-related expenditure, and the search for new weapons goes on. Following initial treatment strategies targeting inotropism and congestion, attention has focused on offsetting the neurohormonal overactivation and three main therapies, including angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor antagonists, β-adrenoceptor antagonists, and mineralocorticoid receptor antagonists, have been the foundation of standard treatment for patients with HF. Recently, a paradigm shift, including angiotensin receptor-neprilysin inhibitor, sodium glucose co-transporter 2 inhibitor, and ivabradine, has been added. Moreover, soluble guanylate cyclase stimulator, elamipretide, and omecamtiv mecarbil have come out as a next-generation therapeutic agent for patients with HF. Although these pharmacologic therapies have been significantly successful in relieving symptoms, there is still no complete cure for HF. We may be currently entering a new era of treatment for HF with animal experiments and human clinical trials assessing the value of antibody-based immunotherapy and gene therapy as a novel therapeutic strategy. Such tempting therapies still have some challenges to be addressed but may become a weighty option for treatment of HF. This review article will compile the paradigm shifts in HF treatment over the past dozen years or so and illustrate current landscape of antibody-based immunotherapy and gene therapy as a new therapeutic algorithm for patients with HF.

Combination of ADAM17 knockdown with eplerenone is more effective than single therapy in ameliorating diabetic cardiomyopathy

Background

The renin-angiotensin-aldosterone system (RAAS) members, especially Ang II and aldosterone, play key roles in the pathogenesis of diabetic cardiomyopathy (DCM). Angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers combined with aldosterone receptor antagonists (mineralocorticoid receptor antagonists) have substantially improved clinical outcomes in patients with DCM. However, the use of the combination has been limited due to its high risk of inducing hyperkalemia.

Methods

Type 1 diabetes was induced in 8-week-old male C57BL/6J mice by intraperitoneal injection of streptozotocin at a dose of 55 mg/kg for 5 consecutive days. Adeno-associated virus 9-mediated short-hairpin RNA (shRNA) was used to knock down the expression of ADAM17 in mice hearts. Eplerenone was administered via gavage at 200 mg/kg daily for 4 weeks. Primary cardiac fibroblasts were exposed to high glucose (HG) in vitro for 24 h to examine the cardiac fibroblasts to myofibroblasts transformation (CMT).

Results

Cardiac collagen deposition and CMT increased in diabetic mice, leading to cardiac fibrosis and dysfunction. In addition, ADAM17 expression and activity increased in the hearts of diabetic mice. ADAM17 inhibition and eplerenone treatment both improved diabetes-induced cardiac fibrosis, cardiac hypertrophy and cardiac dysfunction, ADAM17 deficiency combined with eplerenone further reduced the effects of cardiac fibrosis, cardiac hypertrophy and cardiac dysfunction compared with single therapy in vivo. High-glucose stimulation promotes CMT in vitro and leads to increased ADAM17 expression and activity. ADAM17 knockdown and eplerenone pretreatment can reduce the CMT of fibroblasts that is induced by high glucose levels by inhibiting TGFβ1/Smad3 activation; the combination of the two can further reduce CMT compared with single therapy in vitro.

Conclusion

Our findings indicated that ADAM17 knockout could improve diabetes-induced cardiac dysfunction and remodeling through the inhibition of RAAS overactivation when combined with eplerenone treatment, which reduced TGF-β1/Smad3 pathway activation-mediated CMT. The combined intervention of ADAM17 deficiency and eplerenone therapy provided additional cardiac protection compared with a single therapy alone without disturbing potassium level. Therefore, the combination of ADAM17 inhibition and eplerenone is a potential therapeutic strategy for human DCM.

The New Challenge of Obesity - Obesity-Associated Nephropathy

In recent years, obesity has become one of the major diseases that affect human health and consume human health resources, especially when it causes comorbidities such as hypertension, diabetes, cardiovascular disease and kidney disease. Many studies have demonstrated that obesity is associated with the development of chronic kidney disease and can exacerbate the progression of end-stage renal disease. This review described the mechanisms associated with the development of obesity-associated nephropathy and the current relevant therapeutic modalities, with the aim of finding new therapeutic targets for obesity-associated nephropathy. The mechanisms of obesity-induced renal injury include, in addition to the traditional alterations in renal hemodynamics, the involvement of various mechanisms such as macrophage infiltration in adipose tissue, alterations in adipokines (leptin and adiponectin), and ectopic deposition of lipids. At present, there is no "point-to-point" treatment for obesity-induced kidney injury. The renin-angiotensin-aldosterone system (RAAS) inhibitors, sodium-dependent glucose transporter 2 (SGLT-2) inhibitors and bariatric surgery described in this review can reduce urinary protein to varying degrees and delay the progression of kidney disease. In addition, recent studies on the therapeutic effects of intestinal flora on obesity may reduce the incidence of obesity-related kidney disease from the perspective of primary prevention. Both of these interventions have their own advantages and disadvantages, so the continuous search for the mechanism of obesity-induced related kidney disease will be extremely helpful for the future treatment of obesity-related kidney disease.

Role of the CCL5 and Its Receptor, CCR5, in the Genesis of Aldosterone-Induced Hypertension, Vascular Dysfunction, and End-Organ Damage

BACKGROUND

Aldosterone has been described to initiate cardiovascular diseases by triggering exacerbated sterile vascular inflammation. The functions of CCL5 (C-C motif chemokine ligand 5) and its receptor CCR5 (C-C motif chemokine receptor 5) are well known in infectious diseases, their contributions to aldosterone-induced vascular injury and hypertension remain unknown.

METHODS

We analyzed the vascular profile, blood pressure, and renal damage in wild-type (CCR5+/+) and CCR5 knockout (CCR5-/-) mice treated with aldosterone (600 µg/kg per day for 14 days) while receiving 1% saline to drink. Vascular function was analyzed in aorta and mesenteric arteries, blood pressure was measured by telemetry and renal injury and inflammation were analyzed via histology and flow cytometry. Endothelial cells were used to study the molecular signaling whereby CCL5 induces endothelial dysfunction.

RESULTS

Aldosterone treatment resulted in exaggerated CCL5 circulating levels and vascular CCR5 expression in CCR5+/+ mice accompanied by endothelial dysfunction, hypertension, and renal inflammation and damage. CCR5-/- mice were protected from these aldosterone-induced effects. Mechanistically, we demonstrated that CCL5 increased NOX1 (NADPH oxidase 1) expression, reactive oxygen species formation, NFκB (nuclear factor kappa B) activation, and inflammation and reduced NO production in isolated endothelial cells. These effects were abolished by antagonizing CCR5 with Maraviroc. Finally, aorta incubated with CCL5 displayed severe endothelial dysfunction, which is prevented by blocking NOX1, NFκB, or CCR5.

CONCLUSIONS

Our data demonstrate that CCL5/CCR5, through activation of NFκB and NOX1, is critically involved in aldosterone-induced vascular and renal damage and hypertension placing CCL5 and CCR5 as potential therapeutic targets for conditions characterized by aldosterone excess.

Mineralocorticoid promotes intestinal inflammation through receptor dependent IL17 production in ILC3s

Aldosterone is a key mineralocorticoid involved in regulating the concentration of blood electrolytes and physiological volume balance. Activation of mineralocorticoid receptor (MR) has been recently reported to participate in adaptive and innate immune responses under inflammation. Here, we evaluated the role of aldosterone and MR in inflammation bowel diseases (IBD). Aldosterone elevated in the colon of DSS-induced colitis mice. Aldosterone addition induced IL17 production and ROS/RNS level in group 3 innate lymphoid cells (ILC3s) and exacerbated intestinal injury. A selective mineralocorticoid receptor antagonism, eplerenone, inhibited IL17-producing ILC3s and its ROS/RNS production, protected mice from DSS-induced colitis. Mice lacking Nr3c2 (MR coding gene) in ILC3s exhibited decreased IL17 and ROS/RNS production, which alleviated colitis and colitis-associated colorectal cancer (CAC). Further experiments revealed that MR could directly bind to IL17A promoter and facilitate its transcription, which could be enhanced by aldosterone. Thus, our findings demonstrated the critical role of aldosterone-MR-IL17 signaling in ILC3s and gut homeostasis, indicating the therapeutic strategy of eplerenone in IBD clinical trial.

Fibrosis in Chronic Kidney Disease: Pathophysiology and Therapeutic Targets

Chronic kidney disease (CKD) is a slowly progressive condition characterized by decreased kidney function, tubular injury, oxidative stress, and inflammation. CKD is a leading global health burden that is asymptomatic in early stages but can ultimately cause kidney failure. Its etiology is complex and involves dysregulated signaling pathways that lead to fibrosis. Transforming growth factor (TGF)-β is a central mediator in promoting transdifferentiation of polarized renal tubular epithelial cells into mesenchymal cells, resulting in irreversible kidney injury. While current therapies are limited, the search for more effective diagnostic and treatment modalities is intensive. Although biopsy with histology is the most accurate method of diagnosis and staging, imaging techniques such as diffusion-weighted magnetic resonance imaging and shear wave elastography ultrasound are less invasive ways to stage fibrosis. Current therapies such as renin-angiotensin blockers, mineralocorticoid receptor antagonists, and sodium/glucose cotransporter 2 inhibitors aim to delay progression. Newer antifibrotic agents that suppress the downstream inflammatory mediators involved in the fibrotic process are in clinical trials, and potential therapeutic targets that interfere with TGF-β signaling are being explored. Small interfering RNAs and stem cell-based therapeutics are also being evaluated. Further research and clinical studies are necessary in order to avoid dialysis and kidney transplantation.

Mineralocorticoid receptor antagonists and atrial fibrillation: a meta-analysis of clinical trials

BACKGROUND AND AIMS

Mineralocorticoid receptor antagonists (MRAs) improve cardiovascular outcomes in a variety of settings. This study aimed to assess whether cardioprotective effects of MRAs are modified by heart failure (HF) and atrial fibrillation (AF) status and to study their impact on AF events.

METHODS

MEDLINE, Embase, and Cochrane Central databases were searched to 24 March 2023 for randomized controlled trials evaluating the efficacy of MRAs as compared with placebo or usual care in reducing cardiovascular outcomes and AF events in patients with or at risk for cardiovascular diseases. Random-effects models and interaction analyses were used to test for effect modification.

RESULTS

Meta-analysis of seven trials (20 741 participants, mean age: 65.6 years, 32% women) showed that the efficacy of MRAs, as compared with placebo, in reducing a composite of cardiovascular death or HF hospitalization remains consistent across patients with HF [risk ratio = 0.81; 95% confidence interval (CI): 0.67-0.98] and without HF (risk ratio = 0.84; 95% CI: 0.75-0.93; interaction P = .77). Among patients with HF, MRAs reduced cardiovascular death or HF hospitalization in patients with AF (hazard ratio = 0.95; 95% CI: 0.54-1.66) to a similar extent as in those without AF (hazard ratio = 0.82; 95% CI: 0.63-1.07; interaction P = .65). Pooled data from 20 trials (21 791 participants, mean age: 65.2 years, 31.3% women) showed that MRAs reduce AF events (risk ratio = 0.76; 95% CI: 0.67-0.87) in both patients with and without prior AF.

CONCLUSIONS

Mineralocorticoid receptor antagonists are similarly effective in preventing cardiovascular events in patients with and without HF and most likely retain their efficacy regardless of AF status. Mineralocorticoid receptor antagonists may also be moderately effective in preventing incident or recurrent AF events.

Aldosterone and aldosterone synthase inhibitors in cardiorenal disease

Modulation of the renin-angiotensin-aldosterone system is a foundation of therapy for cardiovascular and kidney diseases. Excess aldosterone plays an important role in cardiovascular disease, contributing to inflammation, fibrosis, and dysfunction in the heart, kidneys, and vasculature through both genomic and mineralocorticoid receptor (MR)-mediated as well as nongenomic mechanisms. MR antagonists have been a key therapy for attenuating the pathologic effects of aldosterone but are associated with some side effects and may not always adequately attenuate the nongenomic effects of aldosterone. Aldosterone is primarily synthesized by the CYP11B2 aldosterone synthase enzyme, which is very similar in structure to other enzymes involved in steroid biosynthesis including CYP11B1, a key enzyme involved in glucocorticoid production. Lack of specificity for CYP11B2, off-target effects on the hypothalamic-pituitary-adrenal axis, and counterproductive increased levels of bioactive steroid intermediates such as 11-deoxycorticosterone have posed challenges in the development of early aldosterone synthase inhibitors such as osilodrostat. In early-phase clinical trials, newer aldosterone synthase inhibitors demonstrated promise in lowering blood pressure in patients with treatment-resistant and uncontrolled hypertension. It is therefore plausible that these agents offer protection in other disease states including heart failure or chronic kidney disease. Further clinical evaluation will be needed to clarify the role of aldosterone synthase inhibitors, a promising class of agents that represent a potentially major therapeutic advance.

Multifocal, Asymmetric Bilateral Primary Aldosteronism Cannot be Excluded by Strong Adrenal Vein Sampling Lateralization: An International Retrospective Cohort Study

BACKGROUND

Primary aldosteronism (PA) has been broadly dichotomized into unilateral and bilateral forms. Adrenal vein sampling (AVS) lateralization indices (LI) ≥2 to 4 are the standard-of-care to recommend unilateral adrenalectomy for presumed unilateral PA. We aimed to assess the rates and characteristics of residual PA after AVS-guided adrenalectomy.

METHODS

We conducted an international, retrospective, cohort study of patients with PA from 7 referral centers who underwent unilateral adrenalectomy based on LI≥4 on baseline and/or cosyntropin-stimulated AVS. Aldosterone synthase (CYP11B2) immunohistochemistry and next generation sequencing were performed on available formalin-fixed paraffin-embedded adrenal tissue.

RESULTS

The cohort included 283 patients who underwent AVS-guided adrenalectomy, followed for a median of 326 days postoperatively. Lack of PA cure was observed in 16% of consecutive patients, and in 22 patients with lateralized PA on both baseline and cosyntropin-stimulated AVS. Among patients with residual PA postoperatively, 73% had multiple CYP11B2 positive areas within the resected adrenal tissue (versus 23% in those cured), wherein CACNA1D mutations were most prevalent (63% versus 33% in those cured). In adjusted regression models, independent predictors of postoperative residual PA included Black versus White race (odds ratio, 5.10 [95% CI, 1.45-17.86]), AVS lateralization only at baseline (odds ratio, 8.93 [95% CI 3.00-26.32] versus both at baseline and after cosyntropin stimulation), and CT-AVS disagreement (odds ratio, 2.75 [95% CI, 1.20-6.31]).

CONCLUSIONS

Multifocal, asymmetrical bilateral PA is relatively common, and it cannot be excluded by robust AVS lateralization. Long-term postoperative monitoring should be routinely pursued, to identify residual PA and afford timely initiation of targeted medical therapy.

Association of the trajectory of plasma aldosterone concentration with the risk of cardiovascular disease in patients with hypertension: a cohort study

The purpose of this study was to determine the long-term pattern of plasma aldosterone concentration (PAC) trajectories and to explore the relationship between PAC trajectory patterns and cardiovascular disease (CVD) risk in patients with hypertension. Participants were surveyed three times between 2010 and 2016, and latent mixed modeling was employed to determine the trajectory of PAC over the exposure period (2010-2016). A Cox regression analysis was used to examine the association between PAC trajectory patterns and the risk of CVD (stroke and myocardial infarction). Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were calculated and reported. During a median follow-up of 4.10 (3.37-4.50) years, 82 incident CVD cases (33 myocardial infarction cases and 49 stroke cases) were identified. Among all three PAC models, the high-stability PAC pattern exhibited the highest risk of CVD. After full adjustment for all covariables, HRs were 2.19 (95% CI 1.59-3.01) for the moderate-stable pattern and 2.56 (95% CI 1.68-3.91) for the high-stable pattern in comparison to the low-stable pattern. Subgroup and sensitivity analyses verified this association. The presence of a high-stable PAC trajectory pattern is associated with an elevated risk of CVD in hypertensive patients. Nevertheless, more studies are warranted to confirm these findings.

Efficacy and safety of nonsteroidal mineralocorticoid receptor antagonists for renal and cardiovascular outcomes in patients with chronic kidney disease: a meta-analysis of randomized clinical trials

Objective: To systematically review the efficacy and safety of nonsteroidal mineralocorticoid receptor antagonists (MRAs) in chronic kidney disease (CKD). Methods: We systematically searched six databases to identify randomized controlled trials (RCTs) about nonsteroidal MRAs for CKD, from inception to 22 August 2023. Two reviewers independently screened the retrieved articles, extracted data, and assessed the risk of bias of included RCTs using the Cochrane risk of bias tool. We then conducted meta-analysis of the data using Stata 17.0 software. Results: 11 RCTs (n = 15,817) were included in this meta-analysis. Compared with placebo, nonsteroidal MRAs significantly reduced the proportion of patients with ≥40% decline in estimated glomerular filtration rate (eGFR) from baseline [RR = 0.85, 95% CI (0.78, 0.92), p < 0.001], although the magnitude of eGFR reduction was greater [WMD = -2.83, 95% CI (-3.95, -1.72), p < 0.001]. The experimental group also had lower incidence of composite renal outcome [RR = 0.86, 95% CI (0.79, 0.93), p < 0.001] and greater reduction in urine albumin-to-creatinine ratio (UACR) from baseline [WMD = -0.41, 95% CI (-0.49, -0.32), p < 0.001], as well as reduced cardiovascular events [RR = 0.88, 95% CI (0.80, 0.95), p = 0.003]. MRAs did not increase any adverse events compared to placebo [RR = 1.00, 95% CI (0.99, 1.01), p = 0.909], but had higher incidence of hyperkalemia [RR = 2.05, 95% CI (1.85, 2.280), p < 0.001]. Compared with eplerenone, there was no significant difference in the proportion of patients with ≥40% decline in eGFR [RR = 0.57, 95% CI (0.18, 1.79), p = 0.335] or hyperkalemia [RR = 0.95, 95%CI (0.48, 1.88), p = 0.875]. Conclusion: Nonsteroidal MRAs can reduce the incidence of end-stage renal disease and cardiovascular adverse events in patients. Although there was still a risk of hyperkalemia compared to placebo, there was no significant difference in any adverse events compared to either placebo or eplerenone. It has become a new option for drug treatment of CKD patients, but more clinical trials are still needed to verify its efficacy and safety. Especially further direct comparison of the nonsteroidal MRAs to eplerenone in view of the relatively small number of patients reviewed are needed.

Cardiac and Renal Fibrosis, the Silent Killer in the Cardiovascular Continuum: An Up-to-Date

Cardiovascular disease (CVD) and chronic kidney disease (CKD) often coexist and have a major impact on patient prognosis. Organ fibrosis plays a significant role in the pathogenesis of cardio-renal syndrome (CRS), explaining the high incidence of heart failure and sudden cardiac death in these patients. Various mediators and mechanisms have been proposed as contributors to the alteration of fibroblasts and collagen turnover, varying from hemodynamic changes to the activation of the renin-angiotensin system, involvement of FGF 23, and Klotho protein or collagen deposition. A better understanding of all the mechanisms involved has prompted the search for alternative therapeutic targets, such as novel inhibitors of the renin-angiotensin-aldosterone system (RAAS), serelaxin, and neutralizing interleukin-11 (IL-11) antibodies. This review focuses on the molecular mechanisms of cardiac and renal fibrosis in the CKD and heart failure (HF) population and highlights the therapeutic alternatives designed to target the responsible pathways.

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.

Macrophages polarization in renal inflammation and fibrosis animal models (Review)

Chronic kidney disease (CKD) is a significant public health concern. Renal fibrosis is the final common pathway in the progression of kidney diseases, irrespective of the initial injury. Substantial evidence underscores the pivotal role of renal inflammation in the genesis of renal fibrosis. The presence of macrophages within normal renal tissue is significantly increased within diseased renal tissue, indicative of their crucial regulatory function in inflammation and fibrosis. Macrophages manifest a high degree of heterogeneity, exhibiting distinct phenotypic and functional traits in response to diverse stimuli within the local microenvironment in various types of kidney diseases. Broadly, macrophages are categorized into two principal groups: Classically activated, designated as M1 macrophages and alternatively activated, designated as M2 macrophages. A number of experimental models are widely used to study the underlying mechanisms driving renal inflammation and fibrosis progression. The present review delineated the phenotypic and functional attributes of macrophages present in diverse induced models, analyzing their disposition in relation to M1 and M2 polarization states.

Evaluation of a Best-Practice Advisory for Primary Aldosteronism Screening

Importance

Primary aldosteronism (PA) is a common cause of secondary hypertension and an independent risk factor for cardiovascular morbidity and mortality. Fewer than 2% to 4% of patients at risk are evaluated for PA.

Objective

To develop and evaluate an electronic health record best-practice advisory (BPA) that assists with PA screening.

Design, Setting, and Participants

This prospective quality improvement study was conducted at academic center outpatient clinics. Data analysis was performed between February and June 2023 and included adults with hypertension and at least 1 of the following: 4 or more current antihypertensive medications; hypokalemia; age younger than 35 years; or adrenal nodule(s). Patients previously tested for PA were excluded.

Exposure

A noninterruptive BPA was developed to trigger for PA screening candidates seen in outpatient setting by clinicians who treat hypertension. The BPA included an order set for PA screening and a link to results interpretation guidance.

Main Outcomes and Measures

(1) The number of PA screening candidates identified by the BPA between October 1, 2021, and December 31, 2022; (2) the rates of PA screening; and (3) the BPA use patterns, stratified by physician specialty were assessed.

Results

Over 15 months, the BPA identified 14 603 unique candidates (mean [SD] age, 65.5 [16.9] years; 7300 women [49.9%]; 371 [2.5%] Asian, 2383 [16.3%] Black, and 11 225 [76.9%] White individuals) for PA screening, including 7028 (48.1%) with treatment-resistant hypertension, 6351 (43.5%) with hypokalemia, 1537 (10.5%) younger than 35 years, and 445 (3.1%) with adrenal nodule(s). In total, 2040 patients (14.0%) received orders for PA screening. Of these, 1439 patients (70.5%) completed the recommended screening within the system, and 250 (17.4%) had positive screening results. Most screening orders were placed by internists (40.0%) and family medicine physicians (28.1%). Family practitioners (80.3%) and internists (68.9%) placed most orders via the embedded order set, while specialists placed most orders (83.0%-95.4%) outside the BPA. Patients who received screening were younger and included more women and Black patients than those not screened. The likelihood of screening was higher among patients with obesity and dyslipidemia and lower in those with chronic kidney disease and established cardiovascular complications.

Conclusions and Relevance

The study results suggest that noninterruptive BPAs are potentially promising PA screening-assistance tools, particularly among primary care physicians. Combined with artificial intelligence algorithms that optimize the detection yield, refined BPAs may contribute to personalized hypertension care.

Overview of the safety, efficiency, and potential mechanisms of finerenone for diabetic kidney diseases

Diabetic kidney disease (DKD) is a common disorder with numerous severe clinical implications. Due to a high level of fibrosis and inflammation that contributes to renal and cardiovascular disease (CVD), existing treatments have not effectively mitigated residual risk for patients with DKD. Excess activation of mineralocorticoid receptors (MRs) plays a significant role in the progression of renal and CVD, mostly by stimulating fibrosis and inflammation. However, the application of traditional steroidal MR antagonists (MRAs) to DKD has been limited by adverse events. Finerenone (FIN), a third-generation non-steroidal selective MRA, has revealed anti-fibrotic and anti-inflammatory effects in pre-clinical studies. Current clinical trials, such as FIDELIO-DKD and FIGARO-DKD and their combined analysis FIDELITY, have elucidated that FIN reduces the kidney and CV composite outcomes and risk of hyperkalemia compared to traditional steroidal MRAs in patients with DKD. As a result, FIN should be regarded as one of the mainstays of treatment for patients with DKD. In this review, the safety, efficiency, and potential mechanisms of FIN treatment on the renal system in patients with DKD is reviewed.