Hecogenin (HEC) is a steroidal saponin found in many plant species and serves as a precursor for steroidal drugs. The diuretic effects of HEC and its derivative, hecogenin acetate (HA), remain largely unexplored. The present study aimed to explore the potential diuretic effects of HEC and HA compared to furosemide (FUR) and spironolactone (SPIR). Additionally, the study aimed to explore the underlying mechanism particularly focusing on aldosterone synthase gene expression. Fifty-four Sprague-Dawley rats were allocated into nine groups (Group 1-9). Group 1 (control) received the vehicle, Groups 2 received FUR 10 mg/kg, Group 3, 4, and 5 were given HEC, while Groups 6, 7 and 8 received HA i.p at doses of 5, 10, and 25 mg/kg, respectively. Group 9 received SPIR i.p at the dose of 25 mg/kg. Urine volume, diuretic index and diuretic activity were monitored at 1, 2, 3, 4, 5, 6, and 24 h post-administration. Treatment was given daily for seven days. After that, rats were sacrificed and blood was collected for serum electrolytes determination. Adrenal glands were dissected out for gene expression studies. The results revealed that HEC and HA at the administered doses significantly and dose-dependently increased urine and electrolyte excretion. These results were primarily observed at 25 mg/kg of each compound. Gene expression studies demonstrated a dose-dependent reduction in aldosterone synthase gene expression, suggesting aldosterone synthesis inhibition as a potential mechanism for their diuretic activity. Notably, HA exhibited more pronounced diuretic effects surpassing those of HEC. This enhanced diuretic activity of HA can be attributed to its stronger impact on aldosterone synthase inhibition. These findings offer valuable insights into the diuretic effects of both HEC and HA along with their underlying molecular mechanisms.

Background: Aldosterone synthase (CYP11B2) is crucial for aldosterone production, and variations in its gene may influence type 2 diabetes mellitus (T2DM) development. This study explores the link between two single nucleotide polymorphisms (SNPs) in the CYP11B2 gene - -344T/C and K173R and T2DM in the Moroccan population . Methods: The research involved 86 individuals with T2DM and 75 control subjects. Genotyping for the -344T/C and K173R SNPs was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis . Result: Results indicated significant differences in the genotype and allelic distribution of the CYP11B2 K173R polymorphism between T2DM patients and control subjects, with P-values of 0.02 and 0.04, respectively. The -344T/C polymorphism showed no significant genomic level differences, but its allelic variations were statistically significant (P=0.01), indicating a notable association between the C allele and T2DM. Furthermore, the K173R polymorphism was found to significantly increase T2DM risk, with a 2.34-fold higher risk in individuals carrying the KR genotype. The study also examined the combined effect of these SNPs. The dominant model analysis (TT vs. TC+CC and KK vs. KR+RR) showed significant differences between T2DM patients and controls for both SNPs. Additionally, a haplotype-based analysis revealed that the C-R haplotype was associated with an increased risk of T2DM. Conclusion: Our study suggests a significant association between the CYP11B2-K173R polymorphism and T2DM in the Moroccan population. Conversely, while the CYP11B2 -344T/C polymorphism exhibits a significant difference in allelic distribution, no significant difference is observed at the genomic level.

The human adrenal cortex secretes aldosterone and cortisol as major corticosteroids. For their production, CYP11B2 and CYP11B1 catalyze the last steps in the syntheses of aldosterone and cortisol, respectively. In our previous study, CYP11B2 was the first successfully purified from rat adrenals and human clinical samples and then was proved to be aldosterone synthase. We demonstrated the immunohistochemistry for CYP11B2 of both rats and humans and applied it clinically to visualize the functional histology of aldosterone-producing adenoma (APA) causing primary aldosteronism (PA). We discovered aldosterone-producing cell clusters (APCCs) and possible APCC-to-APA transitional lesions (pAATLs) and further visualized aldosterone-producing lesions for rare forms of PA including familial hyperaldosteronism type 3 and novel non-familial juvenile PA. Here we review the history of our research on aldosterone-producing lesions.

Adrenal insufficiency (AI) is a severe endocrine disorder characterized by insufficient glucocorticoid (GC) and/or mineralocorticoid (MC) secretion by the adrenal glands, due to impaired adrenal function (primary adrenal insufficiency, PAI) or to insufficient adrenal stimulation by pituitary ACTH (secondary adrenal insufficiency, SAI) or tertiary adrenal insufficiency due to hypothalamic dysfunction. In this review, we describe rare genetic causes of PAI with isolated GC or combined GC and MC deficiencies and we also describe rare syndromes of isolated MC deficiency. In children, the most frequent cause of PAI is congenital adrenal hyperplasia (CAH), a group of adrenal disorders related to steroidogenic enzyme deficiencies, which will not be included in this review. Less frequently, several rare diseases can cause PAI, either affecting exclusively the adrenal glands or with systemic involvement. The diagnosis of these diseases is often challenging, due to the heterogeneity of their clinical presentation and to their rarity. Therefore, the current review aims to provide an overview on these rare genetic forms of paediatric PAI, offering a review of genetic and clinical features and a summary of diagnostic and therapeutic approaches, promoting awareness among practitioners, and favoring early diagnosis and optimal clinical management in suspect cases.

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.

Primary aldosteronism (PA) is the most common form of secondary arterial hypertension, with a prevalence of approximately 20% in patients with resistant hypertension. In the last decade, somatic pathogenic variants in KCNJ5, CACNA1D, ATP1A1 and ATP2B3 genes, which are involved in maintaining intracellular ionic homeostasis and cell membrane potential, were described in aldosterone-producing adenomas (aldosteronomas). All variants in these genes lead to the activation of calcium signaling, the major trigger for aldosterone production. Genetic causes of familial hyperaldosteronism have been expanded through the report of germline pathogenic variants in KCNJ5, CACNA1H and CLCN2 genes. Moreover, PDE2A and PDE3B variants were associated with bilateral PA and increased the spectrum of genetic etiologies of PA. Of great importance, the genetic investigation of adrenal lesions guided by the CYP11B2 staining strongly changed the landscape of somatic genetic findings of PA. Furthermore, CYP11B2 staining allowed the better characterization of the aldosterone-producing adrenal lesions in unilateral PA. Aldosterone production may occur from multiple sources, such as solitary aldosteronoma or aldosterone-producing nodule (classical histopathology) or clusters of autonomous aldosterone-producing cells without apparent neoplasia denominated aldosterone-producing micronodules (non-classical histopathology). Interestingly, KCNJ5 mutational status and classical histopathology of unilateral PA (aldosteronoma) have emerged as relevant predictors of clinical and biochemical outcome, respectively. In this review, we summarize the most recent advances in the pathogenesis of PA and discuss their impact on clinical outcome.

Intracranial stenosis is one of the most common causes of stroke worldwide. Several single nucleotide polymorphisms have been associated with intracranial atherosclerosis, which is inferred to be the most common underlying cause of intracranial large artery stenosis (ILAS). We previously reviewed known genetic variants related to ILAS in predominantly Asian cohorts, but their prevalence and role in ILAS among western multiethnic populations are uncertain.
We leveraged existing imaging and genetic data from the Northern Manhattan Study, a multiethnic prospective cohort study. Based on literature review, we selected adiponectin Q (ADIPOQ) rs2241767 and rs182052, ring finger protein 213 (RNF213) rs112735431, apolipoprotein E (APOE) rs429358, phosphodiesterase 4D (PDE4D) rs2910829, lipoprotein lipase (LPL) rs320, and aldosterone synthase (CYP11B2) rs1799998 variants as candidates to explore. We defined ILAS as luminal stenosis >50% in any intracranial large artery using time-of-flight magnetic resonance angiography (MRA).
We included 1109 participants (mean age 70 ± 9 years, 70% Hispanic, 60% women) in this study. ILAS was identified in 81 (7%) NOMAS participants. Logistic regression analyses adjusted for age, sex, principal components, and vascular risk factors showed ILAS prevalence associated with CYP11B2 rs1799998 under the dominant model (OR = 0.56, 95%CI: 0.35-0.89) and LPL rs320 heterozygote genotype (OR = 1.68, 95%CI: 1.05-2.71). The genotype distributions of ADIPOQ rs2241767 and rs182052, APOE rs429358 and CYP11B2 rs1799998 variants were significantly different among non-Hispanic white and Black, and Hispanic groups. When participants were further stratified by race/ethnicity, the estimates were consistent for CYP11B2 rs1799998 across race/ethnic groups but not for LPL rs320.
The CYP11B2 rs1799998 variant may be a protective genetic factor for ILAS across race/ethnic groups, but the risk of ILAS associated with LPL rs320 varies by race/ethnic group. Further functional studies may help elucidate the role that these variants play in the pathophysiology of ILAS.

UNASSIGNED: Aldosterone synthase (AS) is a key enzyme involved in the final three rate-limiting steps of the biosynthesis pathway of aldosterone, and its inhibition has been considered as an effective strategy to treat hypertension, heart failure, and related cardio-metabolic diseases.
UNASSIGNED: This review provides an update on the discovery and development of aldosterone synthase inhibitors by means of patents published between January 2014 and March 2021. The molecules are classified by pharmaceutical company with progress that has been made in clinical trials being highlighted.
UNASSIGNED: Mineralocorticoid receptor antagonists (MRAs) and aldosterone synthase inhibitors (ASI) represent two of the main approaches for the blockade of aldosterone. Clinical success, as well as foreseen side effects of steroidal MRAs, prompted the discovery and development of ASI. Since the observation of decreased cortisol levels in clinical trials for LCI699, subsequent efforts have been largely focused on improving its selectivity over hCYP11B1. Candidates with improved potency and selectivity are under investigation across a wide range of indications. Whether ASI will provide an additional therapeutic advantage over current safe and selective non-steroidal MRAs is highly anticipated.

Aldosterone synthase deficiency (ASD) is a rare potentially life-threatening genetic disorder that usually presents during infancy due to pathogenic variants in the CYP11B2 gene. Knowledge about CYP11B2 variants in the Arab population is scarce. Here, we present and analyze five Palestinian patients and their different novel pathogenic variants. Data on clinical presentation, electrolytes, plasma renin activity, and steroid hormone levels of five patients diagnosed with ASD were summarized. Sequencing of the CYP11B2 gene exons was followed by evolutionary conservation analysis and structural modeling of the variants. All patients were from highly consanguineous Palestinian families. The patients presented at 1-4 months of age with recurrent vomiting, poor weight gain, hyponatremia, hyperkalemia, and low aldosterone levels. Genetic analysis of the CYP11B2 gene revealed three homozygous pathogenic variants: p.Ser344Profs*9, p.G452W in two patients from an extended family, and p.Q338stop. A previously described pathogenic variant was found in one patient: p.G288S. We described four different CYP11B2 gene pathogenic variants in a relatively small population. Our findings may contribute to the future early diagnosis and therapy for patients with ASD among Arab patients who present with failure to thrive and compatible electrolyte disturbances.

OBJECTIVE: Several recent studies have shown that the aldosterone synthase gene (CYP11B2) -344C/T polymorphism is related to cardiovascular diseases. However, whether the -344C allele influences the incidence of cardiovascular diseases in Chinese patients with hypertension is unclear.
METHODS: Chinese patients with essential hypertension were genotyped for the -344C/T polymorphism in CYP11B2 (n = 755; CC, n = 112; CT, n = 361; TT, n = 282) and followed for 11 years for major adverse cardiovascular events (MACEs), including stroke, onset of coronary artery disease (CAD), and CAD-related death. Established cardiovascular risk factors were used to adjust the multivariate Cox analysis.
RESULTS: After a mean follow-up period of 7.60 ± 1.12 years, a significantly higher incidence of MACEs was seen in patients with the CC genotype than in those with the CT and TT genotypes. The CC variant was significantly and independently predictive of MACEs (hazard ratio = 2.049), CAD (hazard ratio = 1.754), and stroke (hazard ratio = 2.588), but not CAD-related stroke or death.
CONCLUSIONS: The CYP11B2 -344 CC genotype is a risk factor for CAD and stroke, independent of other established cardiovascular risk factors in Chinese patients with hypertension.