Identification of a Novel CYP11B2 Variant in a Family with Varying Degrees of Aldosterone Synthase Deficiency

Isolated aldosterone synthase deficiency is a rare autosomal recessive disorder caused by pathogenic variants in CYP11B2, resulting in impaired aldosterone synthesis. We report on a neonate with isolated aldosterone synthase deficiency caused by a novel homozygous CYP11B2 variant Chr8:NM_000498.3:c.400G>A p.(Gly134Arg). The patient presented shortly after birth with severe signs of aldosterone deficiency. Interestingly, segregation analysis revealed that the patient’s asymptomatic father was also homozygous for the CYP11B2 variant. Biochemical evaluation of the father indicated subclinical enzyme impairment, characterized by elevated aldosterone precursors. Apparently, this homozygous variant led to different clinical phenotypes in two affected relatives. In this manuscript we elaborate on the biochemical and genetic work-up performed and describe potential pitfalls in CYP11B2 sequencing due to its homology to CYP11B1.

Active plasma renin concentration throughout healthy and complicated pregnancy: a systematic review and meta-analysis

BACKGROUND

Pregnancy is characterized by profound circulatory changes and compensatory adjustments in the renin-angiotensin-aldosterone system (RAAS). Differences in regulatory response may antedate or accompany vascular complicated pregnancy. We performed a systematic review and meta-analysis to delineate the trajectory of active plasma renin concentration (APRC) in healthy pregnancy and compare this to complicated pregnancy.

METHODS

We performed a systematic review and meta-analysis on APRC during normotensive and hypertensive pregnancies, using PubMed (NCBI) and Embase (Ovid) databases. We included only studies reporting measurements during pregnancy together with a nonpregnant reference group measurement. Risk of bias was assessed with QUIPS. Ratio of the mean (ROM) and 95% confidence intervals (CI) of APRC values between pregnant and nonpregnant women were estimated for predefined intervals of gestational age using a random-effects model. Meta-regression was used to analyze APRC over time.

RESULTS

In total, we included 18 studies. As compared to nonpregnant, APRC significantly increased as early as the first weeks of healthy pregnancy and stayed increased throughout the whole pregnancy (ROM 2.77; 95% CI 2.26-3.39). APRC in hypertensive complicated pregnancy was not significantly different from nonpregnancy (ROM 1.32; 95% CI 0.97-1.80).

CONCLUSION

Healthy pregnancy is accompanied by a profound rise in APRC in the first trimester that is maintained until term. In hypertensive complicated pregnancy, this increase in APRC is not observed.

Differences in the clinical and hormonal presentation of patients with familial and sporadic primary aldosteronism

Purpose

To compare the clinical and hormonal characteristics of patients with familial hyperaldosteronism (FH) and sporadic primary aldosteronism (PA).

Methods

A systematic review of the literature was performed for the identification of FH patients. The SPAIN-ALDO registry cohort of patients with no suspicion of FH was chosen as the comparator group (sporadic group).

Results

A total of 360 FH (246 FH type I, 73 type II, 29 type III, and 12 type IV) cases and 830 sporadic PA patients were included. Patients with FH-I were younger than sporadic cases, and women were more commonly affected (P = 0.003). In addition, the plasma aldosterone concentration (PAC) was lower, plasma renin activity (PRA) higher, and hypokalemia (P < 0.001) less frequent than in sporadic cases. Except for a younger age (P < 0.001) and higher diastolic blood pressure (P = 0.006), the clinical and hormonal profiles of FH-II and sporadic cases were similar. FH-III had a distinct phenotype, with higher PAC and higher frequency of hypokalemia (P < 0.001), and presented 45 years before sporadic cases. Nevertheless, the clinical and hormonal phenotypes of FH-IV and sporadic cases were similar, with the former being younger and having lower serum potassium levels.

Conclusion

In addition to being younger and having a family history of PA, FH-I and III share other typical characteristics. In this regard, FH-I is characterized by a low prevalence of hypokalemia and FH-III by a severe aldosterone excess causing hypokalemia in more than 85% of patients. The clinical and hormonal phenotype of type II and IV is similar to the sporadic cases.

How should anti-hypertensive medications be adjusted before screening for primary aldosteronism?

Anti-hypertensive medications may affect plasma renin activity and/or plasma aldosterone concentration, misleading the interpretation of the aldosterone-to-renin ratio when screening for primary aldosteronism. The Task Force of Taiwan PA recommends that, when necessary, using α-adrenergic receptor blocking agents, centrally acting α-adrenergic agonists, and/or non-dihydropyridine calcium channel blockers should be considered to control blood pressure before screening for PA. We recommend temporarily holding β-adrenergic receptor blocking agents, mineralocorticoid receptor antagonists, dihydropyridine calcium channel blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and all diuretics before screening for PA. Further large-scale randomized controlled studies are required to confirm the recommendations.

Evidence for the druggability of aldosterone targets in heart failure: A bioinformatics and data science-driven decision-making approach

BACKGROUND

Aldosterone plays a key role in the neurohormonal drive of heart failure. Systematic prioritization of drug targets using bioinformatics and database-driven decision-making can provide a competitive advantage in therapeutic R&D. This study investigated the evidence on the druggability of these aldosterone targets in heart failure.

METHODS

The target disease predictability of mineralocorticoid receptors (MR) and aldosterone synthase (AS) in cardiac failure was evaluated using Open Targets target-disease association scores. The Open Targets database collections were downloaded to MongoDB and queried according to the desired aggregation level, and the results were retrieved from the Europe PMC (data type: text mining), ChEMBL (data type: drugs), Open Targets Genetics Portal (data type: genetic associations), and IMPC (data type: genetic associations) databases. The target tractability of MR and AS in the cardiovascular system was investigated by computing activity scores in a curated ChEMBL database using supervised machine learning.

RESULTS

The medians of the association scores of the MR and AS groups were similar, indicating a comparable predictability of the target disease. The median of the MR activity scores group was significantly lower than that of AS, indicating that AS has higher target tractability than MR [Hodges-Lehmann difference 0.62 (95%CI 0.53-0.70, p < 0.0001]. The cumulative distributions of the overall multiplatform association scores of cardiac diseases with MR were considerably higher than with AS, indicating more advanced investigations on a wider range of disorders evaluated for MR (Kolmogorov-Smirnov D = 0.36, p = 0.0009). In curated ChEMBL, MR had a higher cumulative distribution of activity scores in experimental cardiovascular assays than AS (Kolmogorov-Smirnov D = 0.23, p < 0.0001). Documented clinical trials for MR in heart failures surfaced in database searches, none for AS.

CONCLUSIONS

Although its clinical development has lagged behind that of MR, our findings indicate that AS is a promising therapeutic target for the treatment of cardiac failure. The multiplatform-integrated identification used in this study allowed us to comprehensively explore the available scientific evidence on MR and AS for heart failure therapy.

The role of confirmatory tests in the diagnosis of primary aldosteronism

Confirmatory tests for diagnosis of primary aldosteronism (PA) play an important role in sparing patients with a false-positive aldosterone-to-renin ratio (ARR) screening test from undergoing invasive subtyping procedures. We recommend that patients with a positive ARR test should undergo at least one confirmatory test to confirm or exclude the diagnosis of PA before directly proceeding to subtype studies, except for patients with significant PA phenotypes, including spontaneous hypokalemia, plasma aldosterone concentration >20 ng/dL plus plasma renin activity below a detectable level. Although a gold standard confirmatory test has not been identified, we recommend that saline infusion test and captopril challenge test, which were widely used in Taiwan. Patients with PA have been reported to have a higher prevalence of concurrent autonomous cortisol secretion (ACS). ACS is a biochemical condition of mild cortisol overproduction from adrenal lesions, but without the typical clinical features of overt Cushing's syndrome. Concurrent ACS may result in incorrect interpretation of adrenal venous sampling (AVS) and may lead to adrenal insufficiency after adrenalectomy. We recommend screening for ACS in patients with PA scheduled for AVS examinations as well as for adrenalectomy. We recommend the 1-mg overnight dexamethasone suppression test as screening method to detect ACS.

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.

Effect of amlodipine on the circulating renin-angiotensin-aldosterone system in healthy cats

BACKGROUND

Systemic hypertension (SH) is a common cardiovascular disease in older cats that is treated primarily with the calcium channel blocker amlodipine besylate (AML). The systemic effect of AML on the classical and alterative arms of the renin-angiotensin-aldosterone system (RAAS) in cats is incompletely characterized.

HYPOTHESIS/OBJECTIVES

To determine the effect of AML compared to placebo on circulating RAAS biomarkers in healthy cats using RAAS fingerprinting.

ANIMALS

Twenty healthy client-owned cats.

METHODS

Cats were administered amlodipine besylate (0.625 mg in toto) or placebo by mouth once daily for 14 days in a crossover design with a 4-week washout period. Plasma AML concentrations and RAAS biomarker concentrations were measured at multiple timepoints after the final dose in each treatment period. Time-weighted averages for RAAS biomarkers over 24 hours after dosing were compared between treatment groups using Wilcoxon rank-sum testing.

RESULTS

Compared to placebo, AML treatment was associated with increases in markers of plasma renin concentration (median 44% increase; interquartile range [IQR] 19%-86%; P = .009), angiotensin I (59% increase; IQR 27-101%; P = .006), angiotensin II (56% increase; IQR 5-70%; P = .023), angiotensin IV (42% increase; -19% to 89%; P = .013); and angiotensin 1-7 (38% increase; IQR 9-118%; P = .015).

CONCLUSIONS AND CLINICAL IMPORTANCE

In healthy cats, administration of AML resulted in nonspecific activation of both classical and alternative RAAS pathways.

Treatment decision based on unilateral index from nonadrenocorticotropic hormone-stimulated and adrenocorticotropic hormone-stimulated adrenal vein sampling in primary aldosteronism

OBJECTIVE

Adrenal venous sampling (AVS) is recommended for identifying the subtype of primary aldosteronism before making a surgical treatment decision, but failed cannulation of one adrenal vein is common. To evaluate whether using results of one adrenal vein during AVS could accurately predict unilateral primary aldosteronism.

METHODS

A retrospective study was conducted in primary aldosteronism patients receiving bilaterally or unilaterally successful AVS. The aldosterone-cortisol ratio from the adrenal vein divided by the aldosterone-cortisol ratio from the inferior vena cava (IVC) was calculated as the AV/IVC index.

RESULTS

The study examined 455 patients with primary aldosteronism, including 347 patients with unilateral primary aldosteronism. Among them, 250 and 125 patients received non- adrenocorticotropic hormone (ACTH) and ACTH-stimulated AVS, respectively, and 80 patients received both forms of AVS. Under non-ACTH-stimulated AVS, AUC of the AV/IVC index to diagnose ipsilateral and contralateral primary aldosteronism were 0.778 and 0.924, respectively. The specificity was 100% for both, with sensitivities of 5 and 26%, respectively, when using cutoffs of 17.05 to diagnose ipsilateral primary aldosteronism and 0.15 to diagnose contralateral primary aldosteronism. When using cutoffs of 3.60 and 0.70, the specificity decreased, but if combined with CT results (ipsilateral or contralateral adrenal nodules larger than 10 mm), the specificity could be maintained at 99%, with sensitivities of 33 and 45%, respectively. Under ACTH-stimulated AVS, the AV/IVC index showed similar accuracy to diagnose ipsilateral and contralateral primary aldosteronism.

CONCLUSION

The unilateral AV/IVC index can be used to diagnose unilateral primary aldosteronism during AVS. Combining CT results can increase the accuracy further.

Strategies for subtyping primary aldosteronism

Adrenal venous sampling (AVS) is a crucial method for the lateralization of primary aldosteronism (PA). It is advised to halt the use of the patient's antihypertensive medications and correct hypokalemia prior to undergoing AVS. Hospitals equipped to conduct AVS should establish their own diagnostic criteria based on current guidelines. If the patient's antihypertensive medications cannot be discontinued, AVS can be performed as long as the serum renin level is suppressed. The Task Force of Taiwan PA recommends using a combination of adrenocorticotropic hormone stimulation, quick cortisol assay, and C-arm cone-beam computed tomography to maximize the success of AVS and minimize errors by using the simultaneous sampling technique. If AVS is not successful, an NP-59 (131 I-6-β-iodomethyl-19-norcholesterol) scan can be used as an alternative method to lateralize PA. We depicted the details of the lateralization procedures (mainly AVS, and alternatively NP-59) and their tips and tricks for confirmed PA patients who would consider to undergo surgical treatment (unilateral adrenalectomy) if the subtyping shows unilateral disease.

Aldosterone-to-renin ratio (ARR) as a screening tool for primary aldosteronism (PA)

The aldosterone-to-renin ratio (ARR) is the standard screening test for primary aldosteronism (PA). Because of the poor reproducibility of the ARR, repeat testing is recommended if the result is not compatible with the clinical condition. Various methods to measure renin are used in different hospitals in Taiwan, and the ARR cutoff values also differ among laboratories. The Task Force of Taiwan PA recommend using plasma renin activity (PRA) to calculate ARR instead of direct renin concentration (DRC) unless PRA is unavailable, because PRA is widely used in international guidelines and most studies.

Spironolactone improves left atrial function and atrioventricular coupling in patients with resistant hypertension

To determine the blood pressure independent effects of spironolactone on left atrial (LA) size and function in patients with resistant hypertension (RHTN). Patients with RHTN (n = 36, mean age 55 ± 7) were prospectively recruited. Spironolactone was initiated at 25 mg/day and increased to 50 mg/day after 4 weeks. Other antihypertensives were withdrawn to maintain constant blood pressure. Cardiac magnetic resonance imaging was performed at baseline and after 6 months of spironolactone treatment and changes in LA functional metrics were assessed. LA size and function parameters were improved (p < 0.05) from baseline to month-6: LA volumes indexed to body surface area (LAVI) were reduced (LAVImaximum 41.4 ± 12 vs. 33.2±9.7 mL/m2; LAVIpre-A 32.6 ± 9.8 vs. 25.6 ± 8.1 mL/m2; median LAVIminimum 18.5 [13.9-24.8] vs. 14.1 [10.9-19.2] mL/m2); left atrioventricular coupling index was reduced (28.2 ± 11.5 vs. 22.7 ± 9.2%); LA emptying fractions (LAEF) were increased (median total LAEF 52.4 [48.7-60.3] vs. 55.9 [50.3-61.1] %; active LAEF 40.2 ± 8.6 vs. 43.1 ± 7.8%). LA global longitudinal strain in the active phase was increased (16.3 ± 4.1 vs. 17.8 ± 4.2%). The effect of spironolactone was similar in patients with high (N = 18) and normal (N = 18) aldosterone status (defined by plasma renin activity and 24-h urine aldosterone). Treatment of RHTN with spironolactone is associated with improvements in LA size and function, and atrioventricular coupling, regardless of whether aldosterone levels were normal or high at baseline. This study suggests the need for larger prospective studies examining effects of mineralocorticoid receptor antagonists on atrial function and atrioventricular coupling.

Follow-up care and assessment of comorbidities and complications in patients with primary aldosteronism: The clinical practice guideline of the Taiwan Society of aldosteronism

Primary aldosteronism (PA) is the most common form of endocrine hypertension, characterized by excess aldosterone production that leads to an increased risk of cardiovascular events and target organ damage. Both adrenalectomy and medical treatment have shown efficacy in improving clinical outcomes and comorbidities associated with PA, including a specific subtype of PA with autonomous cortisol secretion (ACS). Understanding the comorbidities of PA and establishing appropriate follow-up protocols after treatment are crucial for physicians to enhance morbidity and mortality outcomes in patients with PA. Additionally, the screening for hypercortisolism prior to surgery is essential, as the prognosis of patients with coexisting PA and ACS differs from those with PA alone. In this review, we comprehensively summarize the comorbidities of PA, encompassing cardiovascular, renal, and metabolic complications. We also discuss various post-treatment outcomes and provide insights into the strategy for glucocorticoid replacement in patients with overt or subclinical hypercortisolism. This clinical practice guideline aims to equip medical professionals with up-to-date information on managing concurrent hypercortisolism, assessing treatment outcomes, and addressing comorbidities in patients with PA, thereby improving follow-up care.

Histamine H2-receptor antagonism improves conduit artery endothelial function and reduces plasma aldosterone level without lowering arterial blood pressure in angiotensin II-hypertensive mice

Aldosterone through the mineralocorticoid receptor MR has detrimental effects on cardiovascular disease. It reduces the bioavailability of nitric oxide and impairs endothelium-dependent vasodilatation. In resistance arteries, aldosterone impairs the sensitivity of vascular smooth muscle cells to nitric oxide by promoting the local secretion of histamine which activates H2 receptors. The present experiments tested in vivo and ex vivo the hypothesis that systemic H2-receptor antagonism reduces arterial blood pressure and improves vasodilatation in angiotensin II-induced chronic hypertension. Hypertension was induced by intravenous infusion of angiotensin II (60 ng kg-1 min-1) in conscious, unrestrained mice infused concomitantly with the H2-receptor antagonist ranitidine (27.8 µg kg-1 min-1) or vehicle for 24 days. Heart rate and arterial blood pressure were recorded by indwelling arterial catheter. Resistance (mesenteric) and conductance (aortae) arteries were harvested for perfusion myography and isometric tension recordings by wire myography, respectively. Plasma was analyzed for aldosterone concentration. ANGII infusion resulted in elevated arterial blood pressure and while in vivo treatment with ranitidine reduced plasma aldosterone concentration, it did not reduce blood pressure. Ranitidine improved ex vivo endothelial function (acetylcholine 10-9 to 10-6 mol L-1) in mesenteric resistance arteries. This was abolished by ex vivo treatment with aldosterone (10-9 mol L-1, 1 h). In aortic segments, in vivo ranitidine treatment impaired relaxation. Activation of histamine H2 receptors promotes aldosterone secretion, does not affect arterial blood pressure, and protects endothelial function in conduit arteries but promotes endothelial dysfunction in resistance arteries during angiotensin II-mediated hypertension. Aldosterone contributes little to angiotensin II-induced hypertension in mice.

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.

Comprehensive characterization of the effect of mineralocorticoid receptor antagonism with spironolactone on the renin-angiotensin-aldosterone system in healthy dogs

OBJECTIVE

To characterize the dose-exposure-response effect of spironolactone on biomarkers of the classical and alternative arms of the renin-angiotensin-aldosterone system (RAAS) in healthy dogs.

ANIMALS

Ten healthy purpose-bred Beagle dogs.

PROCEDURES

Study dogs were randomly allocated to 2 spironolactone dosing groups (2 mg/kg PO q24hr, 4 mg/kg PO q24hr). The dogs received 7-day courses of spironolactone followed by a 14-day washout period in a crossover (AB/BA) design. Angiotensin peptides and aldosterone were measured in serum using equilibrium analysis, and plasma canrenone and 7-α-thiomethyl spironolactone (TMS) were quantified via liquid chromatography-mass spectrometry/mass spectroscopy (LC-MS/MS). Study results were compared before and after dosing and between groups.

RESULTS

Following spironolactone treatment, dogs had a significant increase in serum aldosterone concentration (P = 0.07), with no statistical differences between dosing groups. Significant increases in angiotensin II (P = 0.09), angiotensin I (P = 0.08), angiotensin 1-5 (P = 0.08), and a surrogate marker for plasma renin activity (P = 0.06) were detected compared to baseline following spironolactone treatment during the second treatment period only. Overall, changes from baseline did not significantly differ between spironolactone dosages. RAAS analytes were weakly correlated (R < 0.4) with spironolactone dosage and plasma canrenone or plasma TMS. There were no adverse clinical or biochemical effects seen at any spironolactone dosage during treatment.

CONCLUSIONS

Treatment with spironolactone increased serum aldosterone concentration in healthy dogs and impacted other biomarkers of the classical and alternative arms of the RAAS. There was no difference in effect on the RAAS between 2 and 4 mg/kg/day dosing. Dosage of 4 mg/kg/day was safe and well-tolerated in healthy dogs.

mTOR Regulates Mineralocorticoid Receptor Transcriptional Activity by ULK1-Dependent and -Independent Mechanisms

The mineralocorticoid receptor (MR) is a transcription factor for genes mediating diverse, cell-specific functions, including trophic effects as well as promoting fluid/electrolyte homeostasis. It was reported that in intercalated cells, phosphorylation of the MR at serine 843 (S843) by Unc-51-like kinase (ULK1) inhibits MR activation and that phosphorylation of ULK1 by mechanistic target of rapamycin (mTOR) inactivates ULK1, and thereby prevents MR inactivation. We extended these findings with studies in M1 mouse cortical collecting duct cells stably expressing the rat MR and a reporter gene. Pharmacological inhibition of ULK1 dose-dependently increased ligand-induced MR transactivation, while ULK1 activation had no effect. Pharmacological inhibition of mTOR and CRISPR/gRNA gene knockdown of rapamycin-sensitive adapter protein of mTOR (Raptor) or rapamycin-insensitive companion of mTOR (Rictor) decreased phosphorylated ULK1 and ligand-induced activation of the MR reporter gene, as well as transcription of endogenous MR-target genes. As predicted, ULK1 inhibition had no effect on aldosterone-mediated transcription in M1 cells with the mutated MR-S843A (alanine cannot be phosphorylated). In contrast, mTOR inhibition dose-dependently decreased transcription in the MR-S843A cells, though not as completely as in cells with the wild-type MR-S843. mTOR, Raptor, and Rictor coprecipitated with the MR and addition of aldosterone increased their phosphorylated, active state. These results suggest that mTOR significantly regulates MR activity in at least 2 ways: by suppressing MR inactivation by ULK1, and by a yet ill-defined mechanism that involves direct association with MR. They also provide new insights into the diverse functions of ULK1 and mTOR, 2 key enzymes that monitor the cell's energy status.

Effect of Accessory Renal Arteries on Essential Hypertension and Related Mechanisms

BACKGROUND

This case-control study aimed to determine whether there were differences between patients with essential hypertension with accessory renal arteries (ARAs) and those without ARAs.

METHODS AND RESULTS

The enrolled patients with essential hypertension were divided into the ARA group (n=200) and control group without ARAs (n=238). After propensity matching, 394 patients (197 in each of the 2 groups), were included. The 24-hour BP (4.33/2.43 mm Hg) and daytime BP (4.48/2.61 mm Hg) of patients in the ARA group were significantly higher than those of the control group (P<0.05). The flow-mediated dilation was lower in the ARA group (5.98±2.70 versus 5.18±2.66; P<0.05). In correlation analysis, the horizontal plasma aldosterone concentration had the highest correlation with 24-hour, daytime, and nighttime systolic BP (r=0.263, 0.247, and 0.243, respectively; P<0.05) and diastolic BP (r=0.325, 0.298, and 0.317, respectively; P<0.05). As for multivariate regression analysis, plasma aldosterone concentration was a significant risk factor for elevated 24-hour, daytime, and nighttime systolic BP (β=0.249 [95% CI, 0.150-0.349], 0.228 [95% CI, 0.128-0.329], and 0.282 [95% CI, 0.187-0.377], respectively; P<0.05) and elevated diastolic BP (β=0.289 [95% CI, 0.192-0.385], 0.256 [95% CI, 0.158-0.353], and 0.335 [95% CI, 0.243-0.427], respectively; P<0.05). Direct renin concentration was also a risk factor for 24-hour and daytime BPs, whereas heart rate was a risk factor correlated with 24-hour, daytime, and nighttime diastolic BP (all P<0.05). For the mixed-effects model for repeated measures, the results were similar to results of the multivariate regression analysis (all P<0.05).

CONCLUSIONS

ARAs could contribute a higher BP of patients with essential hypertension and might promote the development of essential hypertension. The mechanism might be related to overactivation of the renin-angiotensin-aldosterone system and sympathetic nervous system.

Association of Dip in eGFR With Clinical Outcomes in Unilateral Primary Aldosteronism Patients After Adrenalectomy

CONTEXT

Primary aldosteronism (PA) leads to kidney function deterioration after treatment, but the effects of the estimated glomerular filtration rate (eGFR) dip following adrenalectomy and its long-term implications are unclear.

OBJECTIVE

This study aims to examine eGFR dip in patients with unilateral PA (uPA) after adrenalectomy and clarify their long-term prognosis.

METHODS

This multicenter prospective population-based cohort study, enrolled patients with uPA who underwent adrenalectomy. Patients were divided into 4 groups based on their eGFR dip ratio. Outcomes investigated included mortality, cardiovascular composite events, and major adverse kidney events (MAKEs).

RESULTS

Among 445 enrolled patients, those with an eGFR dip ratio worse than -30% (n = 74, 16.6%) were older, had higher blood pressure, higher aldosterone concentration, and lower serum potassium levels. During 5.0 ± 3.6 years of follow-up, 2.9% died, 14.6% had cardiovascular composite events, and 17.3% had MAKEs. The group with eGFR dip worse than -30% had a higher risk of MAKEs (P < .001), but no significant differences in mortality (P = .295) or new-onset cardiovascular composite outcomes (P = .373) were found. Multivariate analysis revealed that patients with an eGFR dip ratio worse than -30% were significantly associated with older age (odds ratio [OR], 1.04), preoperative eGFR (OR, 1.02), hypokalemia (OR, 0.45), preoperative systolic blood pressure (OR, 1.03), and plasma aldosterone concentration (OR, 0.99).

CONCLUSION

Within 5 years post adrenalectomy, 17.3% of patients had reduced kidney function. Notably, individuals with an eGFR dip ratio worse than -30% faced higher MAKE risks, underscoring the need to monitor kidney function in PA patients after surgery.

Associations of maternal exposure to 2,4-dichlorophenoxyacetic acid during early pregnancy with steroid hormones among one-month-old infants

BACKGROUND

Exposure to 2,4-dichlorophenoxyacetic acid (2,4-D), a widely used hormonal herbicide, may disrupt steroid hormone homeostasis. However, evidence from population-based studies is limited, especially for one-month-old infants whose steroid hormones are in a state of adjustment to extrauterine life and can be important indicators of endocrine development. This study aimed to explore the associations between maternal 2,4-D exposure during early pregnancy and infant steroid hormone levels.

METHODS

The 885 mother-infant pairs were from a birth cohort in Wuhan, China. Maternal exposure to 2,4-D was determined in urine samples from early pregnancy, and nine steroid hormones were determined in infant urine. The associations of maternal 2,4-D exposure with infant steroid hormones and their product-to-precursor ratios were estimated based on generalized linear models, and bioinformatic analysis was conducted with public databases to explore the potential mechanisms involved.

RESULTS

The detection frequency of 2,4-D was 99.32 %, and the detection frequency of steroid hormones ranged from 98.42 % to 100.00 %. After adjusting for covariates, an interquartile range increase in 2,4-D concentrations was associated with a 7.84 % decrease in 11-deoxycortisol (95 % confidence interval, CI: -14.12 %, -1.10 %), an 8.09 % decrease in corticosterone (95 % CI: -14.56 %, -1.14 %), an 8.67 % decrease in cortisol (95 % CI: -14.43 %, -2.52 %), a 13.00 % decrease in cortisone (95 % CI: -20.64 %, -4.62 %), and an 11.17 % decrease in aldosterone (95 % CI: -19.62 %, -1.83 %). Maternal 2,4-D was also associated with lower infant cortisol/17α-OH-progesterone, cortisol/pregnenolone, and aldosterone/pregnenolone ratios. In bioinformatic analysis, pathways/biological processes related to steroid hormone synthesis and secretion were enriched from target genes of 2,4-D exposure.

CONCLUSIONS

Maternal urinary 2,4-D during early pregnancy was associated with lower infant urinary 11-deoxycortisol, corticosterone, cortisol, cortisone, and aldosterone, reflecting that 2,4-D exposure may interfere with infant steroid hormone homeostasis. Further efforts are still needed to study the relevant health effects of exposure to 2,4-D, particularly for vulnerable populations.

Treatment with Glycyrrhiza glabra Extract Induces Anxiolytic Effects Associated with Reduced Salt Preference and Changes in Barrier Protein Gene Expression

We have previously identified that low responsiveness to antidepressive therapy is associated with higher aldosterone/cortisol ratio, lower systolic blood pressure, and higher salt preference. Glycyrrhiza glabra (GG) contains glycyrrhizin, an inhibitor of 11β-hydroxysteroid-dehydrogenase type-2 and antagonist of toll-like receptor 4. The primary hypothesis of this study is that food enrichment with GG extract results in decreased anxiety behavior and reduced salt preference under stress and non-stress conditions. The secondary hypothesis is that the mentioned changes are associated with altered gene expression of barrier proteins in the prefrontal cortex. Male Sprague-Dawley rats were exposed to chronic mild stress for five weeks. Both stressed and unstressed rats were fed a diet with or without an extract of GG roots for the last two weeks. GG induced anxiolytic effects in animals independent of stress exposure, as measured in elevated plus maze test. Salt preference and intake were significantly reduced by GG under control, but not stress conditions. The gene expression of the barrier protein claudin-11 in the prefrontal cortex was increased in control rats exposed to GG, whereas stress-induced rise was prevented. Exposure to GG-enriched diet resulted in reduced ZO-1 expression irrespective of stress conditions. In conclusion, the observed effects of GG are in line with a reduction in the activity of central mineralocorticoid receptors. The treatment with GG extract or its active components may, therefore, be a useful adjunct therapy for patients with subtypes of depression and anxiety disorders with heightened renin-angiotensin-aldosterone system and/or inflammatory activity.

Striatin Gene Variants Are Associated With Salt Sensitivity of Blood Pressure by Mechanisms That Differ in Women and Men

BACKGROUND

Salt sensitivity of blood pressure (SSBP) is a substantial risk factor for cardiovascular morbidity and mortality. Striatin (STRN) is critical for estrogen and aldosterone nongenomic signaling. However, the role of biological sex on the SSBP phenotype associated with STRN gene variants remains unexplored.

METHOD

Data from 1306 subjects participating in the Hypertensive Pathotype (HyperPATH) Consortium were used to identify STRN gene single-nucleotide variants associated with SSBP. Haploblock analysis revealed a novel diplotype in the upstream regulatory region of STRN (rs888083 and rs6744560), with 31% of subjects being homozygous for the risk diplotype.

RESULTS

Individuals homozygous for the risk diplotype had significantly greater SSBP than nonrisk diplotypes (P<0.009). While a significant genotype/SSBP association was present in both sexes, their potential mechanisms differed. Women, but not men homozygous risk diplotypes, had significantly greater aldosterone levels than nonrisk diplotypes (5.8±0.4 versus 3.2±0.7 ng/dl; P=0.01; liberal Na+ diet, adjusted). Men, but not women, homozygous risk diplotypes, had significantly reduced renal plasma flow response to Angiotensin II than nonrisk diplotypes (delta 95.2±5.2 versus 122.9±10.2 mL/min per 1.73 m2; P=0.01; liberal Na+ diet, adjusted). The single-nucleotide variants composing the risk diplotype were associated with lower STRN mRNA expression in human tissues (in silico).

CONCLUSION

In women, the primary driver of SSBP is increased aldosterone, while in men, it is reduced renal plasma flow responses. Thus, despite a common hypertensive phenotype (SSBP) in both sexes, the specific treatment approaches might differ to increase therapeutic gain and mitigate adverse effects. These genetic- and sex-based observational results require confirmation in a prospective clinical study.