RESUMEN
BACKGROUND: Foetal growth restriction (FGR) occurs when a foetus fails to reach its growth potential. This observational study assessed the expression and significance of cell migration-including protein (CEMIP) and aldosterone synthase (CYP11B2) in the serum of pregnant women with FGR. METHODS: 40 singleton FGR-suffered pregnant women, as well as 40 normal singleton pregnant women, were enrolled. The expression of CEMIP and CYP11B2 in serum was detected in early pregnancy. The correlations between parameters were evaluated. The predictive variables for FGR were determined. The diagnostic value of CEMIP and CYP11B2 for FGR was analysed. RESULTS: CEMIP and CYP11B2 mRNA expression in the serum of pregnant women with FGR decreased (both P < 0.001). CEMIP (95%CI: 0.802-0.921, P < 0.001) and CYP11B2 (95%CI: 0.795-0.907, P < 0.001) mRNA expression in serum and soluble fms like tyrosine kinase-1 (sFLT1)/placental growth factor (PlGF) ratio (95%CI: 0.866-0.974, P < 0.001) were independent predictors of FGR, and CEMIP (r = -0.578, P = 0.001) and CYP11B2 (r = -0.602, P < 0.001) mRNA expression in serum were negatively correlated with sFLT1/PlGF ratio. CEMIP (AUC = 0.741) and CYP11B2 (AUC = 0.764) mRNA expression in serum had good diagnostic value for FGR. CONCLUSION: The expression of CEMIP and CYP11B2 is reduced in the serum of pregnant women with FGR and may become new diagnostic markers for FGR.
Foetal growth restriction is the inability of the foetus to reach its growth potential in the uterus due to various factors. This study aimed to investigate the expression and significance of cell migration-including protein and aldosterone synthase in serum of pregnant women with foetal growth restriction. In our study, we found that the expression of cell migration-including protein and aldosterone synthase in serum of pregnant women with foetal growth restriction were decreased. Cell migration-including protein and aldosterone synthase expression was negatively correlated with soluble fms like tyrosine kinase-1/placental growth factor ratio. In addition, the study also found that cell migration-including protein and aldosterone synthase expression in serum had good diagnostic value for foetal growth restriction.
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Citocromo P-450 CYP11B2 , Retardo del Crecimiento Fetal , Humanos , Femenino , Retardo del Crecimiento Fetal/sangre , Retardo del Crecimiento Fetal/diagnóstico , Retardo del Crecimiento Fetal/genética , Embarazo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/sangre , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , ARN Mensajero/sangreRESUMEN
The distribution of CYP11B2-positive or aldosterone producing adrenocortical cells in human fetuses and children and their age-dependent changes has not been studied. We aimed to explore the changes of aldosterone biosynthesis and age-related histological alterations of the zona glomerulosa in human adrenal gland during fetal and pediatric periods. We first reviewed 125 fetal and pediatric autopsy cases and retrieved 78 adrenals from 70 cases. CYP11B2 immunohistochemistry and quantitative image analysis of its results were performed in all adrenal glands. The ratio of the definitive zone (DZ) or zona glomerulosa (ZG) / the whole adrenocortical areas started to increase in the 2nd trimester, subsequently decreased in the 3rd, increased after birth, peaked in infancy, and then gradually decreased. The ratio of CYP11B2-positive / whole adrenocortical areas remained low during the fetal period but increased after birth, peaked at infancy, and then decreased. The ratio of CYP11B2-positive / DZ or ZG areas and CYP11B2-positive areas / depth of DZ or ZG demonstrated a distinctive bimodal pattern, with one peak in the fetal period and another in the neonatal period to infancy. This is the first study to perform quantitative analysis of the distribution of CYP11B2-positive cells, the histological DZ or ZG, and the development of aldosterone biosynthesis in human adrenal glands during fetal and pediatric periods.
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Aldosterona , Citocromo P-450 CYP11B2 , Feto , Zona Glomerular , Humanos , Citocromo P-450 CYP11B2/metabolismo , Citocromo P-450 CYP11B2/genética , Aldosterona/biosíntesis , Aldosterona/metabolismo , Lactante , Zona Glomerular/metabolismo , Femenino , Preescolar , Feto/metabolismo , Masculino , Recién Nacido , Niño , Glándulas Suprarrenales/metabolismo , Glándulas Suprarrenales/embriología , Adolescente , EmbarazoRESUMEN
Activation of the renin-angiotensin-aldosterone system (RAAS) plays an important pathophysiological role in hypertension. Increased mRNA levels of the angiotensinogen angiotensin-converting enzyme, angiotensin type 1 receptor gene, Agtr1a, and the aldosterone synthase gene, CYP11B2, have been reported in the heart, blood vessels, and kidneys in salt-sensitive hypertension. However, the mechanism of gene regulation in each component of the RAAS in cardiovascular and renal tissues is unclear. Epigenetic mechanisms, which are important for regulating gene expression, include DNA methylation, histone post-translational modifications, and microRNA (miRNA) regulation. A close association exists between low DNA methylation at CEBP-binding sites and increased AGT expression in visceral adipose tissue and the heart of salt-sensitive hypertensive rats. Several miRNAs influence AGT expression and are associated with cardiovascular diseases. Expression of both ACE and ACE2 genes is regulated by DNA methylation, histone modifications, and miRNAs. Expression of both angiotensinogen and CYP11B2 is reversibly regulated by epigenetic modifications and is related to salt-sensitive hypertension. The mineralocorticoid receptor (MR) exists in cardiovascular and renal tissues, in which many miRNAs influence expression and contribute to the pathogenesis of hypertension. Expression of the 11beta-hydroxysteroid dehydrogenase type 2 (HSD11B2) gene is also regulated by methylation and miRNAs. Epigenetic regulation of renal and vascular HSD11B2 is an important pathogenetic mechanism for salt-sensitive hypertension.
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Metilación de ADN , Epigénesis Genética , Hipertensión , Sistema Renina-Angiotensina , Sistema Renina-Angiotensina/genética , Hipertensión/genética , Hipertensión/metabolismo , Animales , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Angiotensinógeno/genética , Angiotensinógeno/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Receptor de Angiotensina Tipo 1/genética , Receptor de Angiotensina Tipo 1/metabolismo , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismoRESUMEN
Dysregulation of the mineralocorticoid hormone aldosterone is an increasingly prevalent cause of hypertension. Aldosterone synthase (CYP11B2) shares 93% homology to 11ß-hydroxylase (CYP11B1), which produces cortisol. Lorundrostat, a highly selective inhibitor of CYP11B2, is a potential safe and effective treatment for aldosterone-dependent, uncontrolled hypertension, including treatment-resistant hypertension. Lorundrostat showed highly selective inhibition of CYP11B2 in vitro, with 374-fold selectivity for CYP11B2 vs. CYP11B1. A first-in-human study of single ascending doses ranging from 5 to 800 mg and multiple ascending doses ranging from 40 to 360 mg once daily was conducted in healthy participants. After single- and multiple-dose administration, lorundrostat plasma levels peaked 1-3 h after administration with a t1/2 of 10-12 h. Plasma aldosterone decreased up to 40% with single 100-mg to 200-mg doses and up to 70% with single 400 to 800-mg doses. Plasma aldosterone returned to baseline within 16 h after single 100-mg doses and multiple once-daily 120-mg doses. Lorundrostat demonstrated a favorable safety profile in healthy participants. Dose- and exposure-dependent inhibition of renal tubular sodium reabsorption was observed across a clinically relevant dose range with no suppression of basal or cosyntropin-stimulated cortisol production and only a modest increase in mean serum potassium.
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Aldosterona , Citocromo P-450 CYP11B2 , Relación Dosis-Respuesta a Droga , Humanos , Citocromo P-450 CYP11B2/antagonistas & inhibidores , Masculino , Adulto , Aldosterona/sangre , Femenino , Persona de Mediana Edad , Adulto Joven , Voluntarios Sanos , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/efectos adversos , Método Doble Ciego , AdolescenteRESUMEN
Hypertension affects one-third of the adult population worldwide, with primary aldosteronism (PA) accounting for at least 5-10% of these cases. The aldosterone synthase enzyme (CYP11B2) plays a pivotal role in PA manifestation, as increased expression of CYP11B2 leads to excess aldosterone synthesis. Physiological expression of CYP11B2 in humans is normally limited to cells of the adrenal zona glomerulosa under tight homeostatic regulation. In PA, however, there are CYP11B2-positive lesions in the adrenal cortex that autonomously secrete aldosterone, highlighting the dysregulation of adrenal cortex zonation and function as a key aspect of PA pathogenesis. Thus, this review aims to summarize the development of the adrenal glands, the key regulators of adrenal cortex homeostasis, and the dysregulation of this homeostasis. It also discusses the development of CYP11B2 inhibitors for therapeutic use in patients with hypertension, as well as the current knowledge of the effects of CYP11B2 inhibition on adrenal cortex homeostasis and cell fate. Understanding the control of adrenal cell fate may offer valuable insights into both the pathogenesis of PA and the development of alternative treatment approaches for PA.
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Glándulas Suprarrenales , Aldosterona , Citocromo P-450 CYP11B2 , Hiperaldosteronismo , Humanos , Aldosterona/metabolismo , Aldosterona/biosíntesis , Citocromo P-450 CYP11B2/metabolismo , Hiperaldosteronismo/metabolismo , Hiperaldosteronismo/patología , Glándulas Suprarrenales/metabolismo , Animales , Corteza Suprarrenal/metabolismo , Corteza Suprarrenal/citología , Hipertensión/metabolismo , Hipertensión/patología , Zona Glomerular/metabolismo , Diferenciación Celular , HomeostasisRESUMEN
Rationale: Sarcoidosis is a granulomatous disorder of unclear cause notable for abnormal elevation of blood and tissue ACE1 (angiotensin converting enzyme 1) levels and activity. ACE1 regulates the renin-angiotensin-aldosterone system (RAAS), the terminal product of which is aldosterone, which selectively engages mineralocorticoid receptors to promote inflammation. Objectives: We sought to determine whether the RAAS promotes sarcoidosis granuloma formation and related inflammatory responses. Methods: Using an established ex vivo model, we first determined whether aldosterone was produced by sarcoidosis granulomas and verified the presence of CYP11B2, the enzyme required for its production. We then evaluated the effects of selective inhibitors of ACE1 (captopril), angiotensin type 1 receptor (losartan), and mineralocorticoid receptors (spironolactone, eplerenone) on granuloma formation, reflected by computer image analysis-generated granuloma area, and selected cytokines incriminated in sarcoidosis pathogenesis. Measurements and Main Results: Aldosterone was spontaneously produced by sarcoidosis peripheral blood mononuclear cells, and both intra- and extracellular levels steadily increased during granuloma formation. In parallel, peripheral blood mononuclear cells were shown to express more CYP11B2 during granuloma formation. Significant inhibition of sarcoidosis granulomas and related cytokines (TNFα, IL-1ß, IFNγ, IL-10) was observed in response to pretreatments with captopril, losartan, spironolactone, or eplerenone, comparable to that of prednisone. Conclusions: The RAAS is intact in sarcoidosis granulomas and contributes significantly to early granuloma formation and to related inflammatory mediator responses, with important implications for clinical management.
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Aldosterona , Citocromo P-450 CYP11B2 , Granuloma , Sistema Renina-Angiotensina , Sarcoidosis , Humanos , Sistema Renina-Angiotensina/efectos de los fármacos , Sistema Renina-Angiotensina/fisiología , Granuloma/tratamiento farmacológico , Aldosterona/metabolismo , Sarcoidosis/tratamiento farmacológico , Sarcoidosis/fisiopatología , Masculino , Femenino , Losartán/farmacología , Losartán/uso terapéutico , Eplerenona/farmacología , Eplerenona/uso terapéutico , Inflamación , Espironolactona/uso terapéutico , Espironolactona/farmacología , Persona de Mediana Edad , Captopril/farmacología , Captopril/uso terapéutico , Citocinas/metabolismo , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Peptidil-Dipeptidasa A/metabolismo , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Antagonistas de Receptores de Mineralocorticoides/farmacologíaRESUMEN
CONTEXT: The search for somatic mutations in adrenals resected from patients with primary aldosteronism (PA) is performed by Sanger sequencing, often implemented with immunohistochemistry (IHC)-guidance focused on aldosterone-producing (CYP11B2-positive) areas. OBJECTIVE: To investigate the impact of double IHC for CYP11B1 and CYP11B2 on Sanger and next-generation sequencing (NGS). METHODS: We investigated 127 consecutive adrenal aldosterone-producing adenomas from consenting surgically cured PA patients using double IHC for CYP11B1 and CYP11B2, by Sanger sequencing and NGS. RESULTS: Double IHC for CYP11B2 and CYP11B1 revealed 3 distinct patterns: CYP11B2-positive adenoma (pattern 1), mixed CYP11B1/CYP11B2-positive adenoma (pattern 2), and adrenals with multiple small CYP11B2-positive nodules (pattern 3). Sanger sequencing allowed detection of KCNJ5 mutations in 44% of the adrenals; NGS revealed such mutations in 10% of those negative at Sanger and additional mutations in 61% of the cases. Importantly the rate of KCNJ5 mutations differed across patterns: 17.8% in pattern 1, 71.4% in pattern 2, and 10.7% in pattern 3 (χ2 = 22.492, P < .001). CONCLUSION: NGS allowed detection of mutations in many adrenals that tested negative at Sanger sequencing. Moreover, the different distribution of KCNJ5 mutations across IHC patterns indicates that IHC-guided sequencing protocols selecting CYP11B2-positive areas could furnish results that might not be representative of the entire mutational status of the excised adrenal, which is important at a time when KCNJ5 mutations are suggested to drive management of patients with aldosterone-producing adenomas.
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Citocromo P-450 CYP11B2 , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Hiperaldosteronismo , Inmunohistoquímica , Mutación , Esteroide 11-beta-Hidroxilasa , Humanos , Hiperaldosteronismo/genética , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/metabolismo , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/genética , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/metabolismo , Esteroide 11-beta-Hidroxilasa/genética , Esteroide 11-beta-Hidroxilasa/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Femenino , Masculino , Persona de Mediana Edad , Adulto , Secuenciación de Nucleótidos de Alto Rendimiento , Adenoma Corticosuprarrenal/genética , Adenoma Corticosuprarrenal/metabolismo , Adenoma Corticosuprarrenal/patología , Adenoma Corticosuprarrenal/diagnóstico , Anciano , Neoplasias de la Corteza Suprarrenal/genética , Neoplasias de la Corteza Suprarrenal/metabolismo , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/patologíaRESUMEN
4-[(5-[2-Methyl-5-(methylsulfonyl)pentan-2-yl]sulfonylpyrimidin-4-yl)amino]benzonitrile 2 was identified as a novel potent aldosterone synthase inhibitor. Compound 2 was found to inhibit human CYP11B2 in the nanomolar range, and showed an aldosterone-lowering effect in a furosemide-treated cynomolgus monkey model. Although human CYP11B2 has the high homology sequence with human CYP11B1, compound 2 showed more than 80 times higher selectivity over human CYP11B1 in vitro.
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Citocromo P-450 CYP11B2 , Inhibidores Enzimáticos , Macaca fascicularis , Pirimidinas , Citocromo P-450 CYP11B2/antagonistas & inhibidores , Citocromo P-450 CYP11B2/metabolismo , Humanos , Animales , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Relación Estructura-Actividad , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Aldosterona/metabolismo , Aldosterona/química , Estructura MolecularRESUMEN
We have previously described local aldosterone synthesis in mouse colon. In the renin-angiotensin-aldosterone system (RAAS), angiotensin II (Ang II) peptide is the physiological factor which stimulates aldosterone synthesis in the adrenal glands. We have recently demonstrated that Ang II stimulates aldosterone synthesis also in mouse colon. Here, we conducted a 75-min ex vivo incubation of murine colonic tissue and evaluated the effects of three other Ang peptides, Ang I (1 µM), Ang III (0.1 µM) and Ang (1-7) (0.1 µM) on aldosterone synthesis. As a possible mechanism, their effects on tissue levels of the rate-limiting enzyme, aldosterone synthase (CYP11B2) were measured by ELISA and Western blot. Ang III significantly elevated the amount of tissue CYP11B2 protein in colon. The values of released aldosterone in colon tissue incubation were increased over the control in the presence of Ang I, II or III, however, being statistically non-significant. In Western blot analysis, the values of tissue CYP11B2 protein content were elevated by Ang I and II. Ang (1-7) alone in colon did not influence CYP11B2 protein levels in the incubation experiment but showed higher aldosterone release without statistical significance. Ang (1-7) showed an antagonistic effect towards Ang II in release of aldosterone in adrenal gland. An overall estimation of a single peptide (three measured variables), the results were always in an increasing direction. The responses of aldosterone synthesis to high levels of glucose (44 mM) and potassium (18.8 mM) as physiological stimulators in vivo were investigated in the colon incubation. Glucose, equal to four times the concentration of the control buffer in the incubation, showed higher values of aldosterone release in colon than control without statistical significance similarly to the effect seen in adrenal glands. Increasing the concentration of potassium in the incubation buffer exerted no effect on colonic aldosterone production. Intriguingly, no correlation was found between aldosterone release and the tissue CYP11B2 protein content in colon. In summary, the response of colonic aldosterone synthesis to different Ang peptides resembles, but is not identical to, the situation in the adrenal glands.
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Aldosterona , Colon , Citocromo P-450 CYP11B2 , Glucosa , Potasio , Animales , Masculino , Ratones , Aldosterona/metabolismo , Angiotensina I/fisiología , Angiotensina II/fisiología , Angiotensina III/fisiología , Colon/metabolismo , Colon/efectos de los fármacos , Citocromo P-450 CYP11B2/metabolismo , Glucosa/metabolismo , Fragmentos de Péptidos/fisiología , Potasio/metabolismoRESUMEN
Despite being the world's top risk factor for death and disability, hypertension awareness and control within the chronic kidney disease (CKD) population have decreased. This is particularly important considering the heightened severity and management challenges of hypertension in CKD patients, whose outcomes are often worse compared with persons with normal kidney function. Therefore, finding novel therapeutics to improve blood pressure control within this vulnerable group is paramount. Although medications that target the renin-angiotensin-aldosterone system remain a mainstay for blood pressure control in most stages of CKD, we discuss novel approaches that may expand their use in advanced CKD. We also review newer tools for blood pressure management that have emerged in recent years, including aldosterone synthase inhibitors, endothelin receptor antagonists, and renal denervation. Overall, the future of hypertension management in CKD appears brighter, with a growing arsenal of tools and a deeper understanding of this complex disease.
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Antihipertensivos , Hipertensión , Insuficiencia Renal Crónica , Humanos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/fisiopatología , Hipertensión/tratamiento farmacológico , Hipertensión/complicaciones , Antihipertensivos/uso terapéutico , Sistema Renina-Angiotensina/efectos de los fármacos , Antagonistas de los Receptores de Endotelina/uso terapéutico , Simpatectomía , Citocromo P-450 CYP11B2/antagonistas & inhibidoresRESUMEN
Aldosterone synthase (CYP11B2) is the rate-limiting enzyme in aldosterone production. In recent years, CYP11B2 has become an appealing target for treating conditions associated with excess aldosterone, such as hypertension, heart failure, and cardiometabolic diseases. Several small-molecule inhibitors of CYP11B2 have demonstrated efficacy in both preclinical studies and clinical trials. Among them, the tetrahydroisoquinoline derivative Baxdrostat has entered clinical trial phases and demonstrated efficacy in treating patients with hypertension. However, the high homology (>93 %) between CYP11B2 and steroid-11ß-hydroxylase (CYP11B1), which catalyzes cortisol production, implies that insufficient drug specificity can lead to severe side effects. Developing selective inhibitors for CYP11B2 remains a considerable challenge that requires ongoing attention. This review summarizes recent research progress on small-molecule inhibitors targeting CYP11B2, focusing on structure-activity relationships (SAR) and structural optimization. It discusses strategies for enhancing the specificity and inhibitory activity of inhibitors, while also exploring potential applications and future prospects for CYP11B2 inhibitors, providing a theoretical foundation for developing the new generation of CYP11B2-targeted medications.
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Enfermedades Cardiovasculares , Citocromo P-450 CYP11B2 , Bibliotecas de Moléculas Pequeñas , Humanos , Citocromo P-450 CYP11B2/antagonistas & inhibidores , Citocromo P-450 CYP11B2/metabolismo , Relación Estructura-Actividad , Enfermedades Cardiovasculares/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Animales , Estructura MolecularRESUMEN
Klotho plays a critical role in the regulation of ion and fluid homeostasis. A previous study reported that haplo-insufficiency of Klotho in mice results in increased aldosterone synthase (CYP11B2) expression, elevated plasma aldosterone, and high blood pressure. This phenotype was presumed to be the result of diminished Klotho expression in zona glomerulosa (zG) cells of the adrenal cortex; however, systemic effects on adrenal aldosterone production could not be ruled out. To examine whether Klotho expressed in the zG is indeed a critical regulator of aldosterone synthesis, we generated a tamoxifen-inducible, zG-specific mouse model of Klotho deficiency by crossing Klotho-flox mice with Cyp11b2-CreERT mice (zG-Kl-KO). Tamoxifen-treated Cyp11b2-CreERT animals (zG-Cre) served as controls. Rosa26-mTmG reporter mice were used for Cre-dependent lineage-marking. Two weeks after tamoxifen induction, the specificity of the zG-Cre line was verified using immunofluorescence analysis to show that GFP expression was restricted to the zG. RNA in situ hybridization revealed a 65% downregulation of Klotho messenger RNA expression in the zG of zG-Kl-KO female mice at age 12 weeks compared to control mice. Despite this significant decrease, zG-Kl-KO mice exhibited no difference in plasma aldosterone levels. However, adrenal CYP11B2 expression and the CYP11B2 promotor regulatory transcription factors, NGFIB and Nurr1, were enhanced. Together with in vitro experiments, these results suggest that zG-derived Klotho modulates Cyp11b2 but does not evoke a systemic phenotype in young adult mice on a normal diet. Further studies are required to investigate the role of adrenal Klotho on aldosterone synthesis in aged animals.
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Corteza Suprarrenal , Hiperaldosteronismo , Femenino , Ratones , Animales , Zona Glomerular/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Aldosterona/metabolismo , Corteza Suprarrenal/metabolismo , Hiperaldosteronismo/genética , Tamoxifeno/farmacologíaRESUMEN
The mitochondrial enzyme cytochrome P450 11B2 (aldosterone synthase) catalyzes the 3 terminal transformations in the biosynthesis of aldosterone from 11-deoxycorticosterone (DOC): 11ß-hydroxylation to corticosterone, 18-hydroxylation, and 18-oxidation. Prior studies have shown that P450 11B2 produces more aldosterone from DOC than from the intermediate corticosterone and that the reaction sequence is processive, with intermediates remaining bound to the active site between oxygenation reactions. In contrast, P450 11B1 (11ß-hydroxylase), which catalyzes the terminal step in cortisol biosynthesis, shares a 93% amino acid sequence identity with P450 11B2, converts DOC to corticosterone, but cannot synthesize aldosterone from DOC. The biochemical and biophysical properties of P450 11B2, which enable its unique 18-oxygenation activity and processivity, yet are not also represented in P450 11B1, remain unknown. To understand the mechanism of aldosterone biosynthesis, we introduced point mutations at residue 320, which partially exchange the activities of P450 11B1 and P450 11B2 (V320A and A320V, respectively). We then investigated NADPH coupling efficiencies, binding kinetics and affinities, and product formation of purified P450 11B1 and P450 11B2, wild-type, and residue 320 mutations in phospholipid vesicles and nanodiscs. Coupling efficiencies for the 18-hydroxylase reaction with corticosterone as the substrate failed to correlate with aldosterone synthesis, ruling out uncoupling as a relevant mechanism. Conversely, corticosterone dissociation rates correlated inversely with aldosterone production. We conclude that intermediate dissociation kinetics, not coupling efficiency, enable P450 11B2 to synthesize aldosterone via a processive mechanism. Our kinetic data also suggest that the binding of DOC to P450 11B enzymes occurs in at least two distinct steps, favoring an induced-fit mechanism.
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Aldosterona , Esteroide 11-beta-Hidroxilasa , Esteroide 11-beta-Hidroxilasa/química , Esteroide 11-beta-Hidroxilasa/genética , Esteroide 11-beta-Hidroxilasa/metabolismo , Corticosterona/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/química , Citocromo P-450 CYP11B2/metabolismo , Catálisis , CinéticaRESUMEN
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.
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Citocromo P-450 CYP11B2 , Diabetes Mellitus Tipo 2 , Polimorfismo de Nucleótido Simple , Humanos , Diabetes Mellitus Tipo 2/genética , Citocromo P-450 CYP11B2/genética , Marruecos , Masculino , Femenino , Persona de Mediana Edad , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Genotipo , Adulto , AncianoRESUMEN
AIM: This Phase I study evaluated the safety and early efficacy of an aldosterone synthase inhibitor (BI 690517) in people with diabetes and albuminuric chronic kidney disease. METHODS: Double-blind, placebo-controlled study (NCT03165240) at 40 sites across Europe. Eligible participants [estimated glomerular filtration rate ≥20 and <75 ml/min/1.73 m2; urine albumin/creatinine ratio (UACR) ≥200 and <3500 mg/g] were randomized 6:1 to receive once-daily oral BI 690517 3, 10 or 40 mg, or eplerenone 25-50 mg, or placebo, for 28 days. The primary endpoint was the proportion of participants with drug-related adverse events (AEs). Secondary endpoints included changes from baseline in the UACR. RESULTS: Fifty-eight participants were randomized and treated from 27 November 2017 to 16 April 2020 (BI 690517: 3 mg, n = 18; 10 mg, n = 13; 40 mg, n = 14; eplerenone, n = 4; placebo, n = 9) for 28 days. Eight (13.8%) participants experienced drug-related AEs [BI 690517: 3 mg (two of 18); 10 mg (four of 13); 40 mg (two of 14)], most frequently constipation [10 mg (one of 13); 40 mg (one of 14)] and hyperkalaemia [3 mg (one of 18); 10 mg (one of 13)]. Most AEs were mild to moderate; one participant experienced severe hyperkalaemia (serum potassium 6.9 mmol/L; BI 690517 10 mg). UACR responses [≥20% decrease from baseline (first morning void urine) after 28 days] were observed for 80.0% receiving BI 690517 40 mg (eight of 10) versus 37.5% receiving placebo (three of eight). Aldosterone levels were suppressed by BI 690517, but not eplerenone or placebo. CONCLUSIONS: BI 690517 was generally well tolerated, reduced plasma aldosterone and may decrease albuminuria in participants with diabetes and albuminuric chronic kidney disease.
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Albuminuria , Insuficiencia Renal Crónica , Humanos , Método Doble Ciego , Masculino , Femenino , Persona de Mediana Edad , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/complicaciones , Albuminuria/tratamiento farmacológico , Anciano , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Antagonistas de Receptores de Mineralocorticoides/efectos adversos , Adulto , Resultado del Tratamiento , Citocromo P-450 CYP11B2/antagonistas & inhibidores , Eplerenona/uso terapéutico , Eplerenona/efectos adversos , Nefropatías Diabéticas/tratamiento farmacológico , Tasa de Filtración Glomerular/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicacionesRESUMEN
Double somatic mutations in CTNNB1 and GNA11/Q have recently been identified in a small subset of aldosterone-producing adenomas (APAs). As a possible pathogenesis of APA due to these mutations, an association with pregnancy, menopause, or puberty has been proposed. However, because of its rarity, characteristics of APA with these mutations have not been well characterized. A 46-year-old Japanese woman presented with hypertension and hypokalemia. She had two pregnancies in the past but had no history of pregnancy-induced hypertension. She had regular menstrual cycle at presentation and was diagnosed as having primary aldosteronism after endocrinologic examinations. Computed tomography revealed a 2 cm right adrenal mass. Adrenal venous sampling demonstrated excess aldosterone production from the right adrenal gland. She underwent right laparoscopic adrenalectomy. The resected right adrenal tumor was histologically diagnosed as adrenocortical adenoma and subsequent immunohistochemistry (IHC) revealed diffuse immunoreactivity of aldosterone synthase (CYP11B2) and visinin like 1, a marker of the zona glomerulosa (ZG), whereas 11ß-hydroxylase, a steroidogenic enzyme for cortisol biosynthesis, was mostly negative. CYP11B2 IHC-guided targeted next-generation sequencing identified somatic CTNNB1 (p.D32Y) and GNA11 (p.Q209H) mutations. Immunofluorescence staining of the tumor also revealed the presence of activated ß-catenin, consistent with features of the normal ZG. The expression patterns of steroidogenic enzymes and related proteins indicated ZG features of the tumor cells. PA was clinically and biochemically cured after surgery. In conclusion, our study indicated that CTNNB1 and GNA11-mutated APA has characteristics of the ZG. The disease could occur in adults with no clear association with pregnancy or menopause.
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Adenoma , Adenoma Corticosuprarrenal , Hiperaldosteronismo , Hipertensión , Adulto , Femenino , Embarazo , Humanos , Persona de Mediana Edad , Adenoma Corticosuprarrenal/complicaciones , Adenoma Corticosuprarrenal/genética , Adenoma Corticosuprarrenal/cirugía , Aldosterona/metabolismo , Citocromo P-450 CYP11B2/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Hiperaldosteronismo/genética , Hiperaldosteronismo/cirugía , Adenoma/genética , Adenoma/cirugía , Adenoma/metabolismo , Hipertensión/complicaciones , Mutación , Subunidades alfa de la Proteína de Unión al GTP/genética , Subunidades alfa de la Proteína de Unión al GTP/metabolismoRESUMEN
Deficiency of 11ß-hydroxylase (11ß-OHD) is the second most common cause of congenital adrenal hyperplasia (CAH), accounting for 0.2-8% of all cases. The disease is transmitted as an autosomal recessive trait and the underlying genetic causes of 11ß-OHD are primarily small pathogenic variants affecting the CYP11B1 gene coding the 11ß-hydroxylase enzyme. However, special events complicate the molecular diagnosis of 11ß-OHD such as an unequal crossing over between the CYP11B2 (coding aldosterone synthase enzyme) and CYP11B1 genes. The resulting allele contains a hybrid gene, with a CYP11B2 5'-end and a CYP11B1 3'-end, where the CYP11B1 gene is under the control of the CYP11B2 promoter and thus not responding to the adrenocorticotropin (ACTH) but to angiotensin II and K+. This leads a reduction of cortisol production in 11ß-OHD. In particular, CYP11B2/CYP11B1 chimeric genes can be distinguished into two groups depending on the breakpoint site: chimeras with breakpoint after the exon 5 of CYP11B2 preserve the aldosterone synthase activity, the others with breakpoint before exon 5 lose this function. In the last case, a more severe phenotype is expected. The aim of this review was to explore the setting of CYP11B2/CYP11B1 chimeras in 11ß-OHD, performing a careful review of clinical literature cases.
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Hiperplasia Suprarrenal Congénita , Esteroide 11-beta-Hidroxilasa , Humanos , Esteroide 11-beta-Hidroxilasa/genética , Citocromo P-450 CYP11B2/genética , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/genética , Hidrocortisona , Oxigenasas de Función MixtaRESUMEN
Baxdrostat is a selective small-molecule aldosterone synthase inhibitor in development for treatment of hypertension and chronic kidney disease. This phase 1, open-label, parallel-group study assessed the safety and pharmacokinetics (PK) of baxdrostat in participants with varying degrees of renal function. Participants were enrolled into control (estimated glomerular filtration rate [eGFR] ≥60 mL/min), moderate to severe renal impairment (eGFR 15-59 mL/min), or kidney failure (eGFR <15 mL/min) groups and received a single 10-mg baxdrostat dose followed by 7 days of inpatient PK blood and urine sampling. Safety was assessed by adverse events, clinical laboratory evaluations, vital signs, physical examinations, and electrocardiograms (ECGs). Thirty-2 participants completed the study. There were no deaths and only 1 mild drug-related adverse event (diarrhea). No clinically meaningful changes in laboratory values, vital signs, physical examinations, or ECGs occurred. Plasma concentration-time curves of baxdrostat were similar among all groups. Urine PK parameters were similar (approximately 12% excreted) in the moderate to severe renal impairment and control groups. Inadequate urine production in the kidney failure group resulted in minimal urinary baxdrostat excretion. Renal impairment had no significant impact on systemic exposure or clearance of baxdrostat, suggesting that dose adjustment due to PK differences in patients with kidney disease is unnecessary.
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Insuficiencia Renal Crónica , Insuficiencia Renal , Humanos , Citocromo P-450 CYP11B2 , Tasa de Filtración Glomerular , RiñónRESUMEN
Hyperaldosteronism is often associated with inappropriate aldosterone production and aldosterone synthase (Cyp11b2) expression. Normally, Cyp11b2 expression is limited to the adrenal zona glomerulosa (ZG) and regulated by angiotensin II which signals through Gq protein-coupled receptors. As cells migrate inwards, they differentiate into 11ß-hydroxylase-expressing zona fasciculata (ZF) cells lacking Cyp11b2. The mechanism causing ZG-specific aldosterone biosynthesis is still unclear. We investigated the effect of chronic Gq signaling using transgenic mice with a clozapine N-oxide (CNO)-activated human M3 muscarinic receptor (DREADD) coupled to Gq (hM3Dq) that was expressed throughout the adrenal cortex. CNO raised circulating aldosterone in the presence of a high sodium diet with greater response seen in females compared to males. Immunohistochemistry and transcriptomics indicated disrupted zonal Cyp11b2 expression while Wnt signaling remained unchanged. Chronic Gq-DREADD signaling also induced an intra-adrenal RAAS in CNO-treated mice. Chronic Gq signaling disrupted adrenal cortex zonal aldosterone production associated with ZF expression of Cyp11b2.