Interaction between accumulated 21-deoxysteroids and mineralocorticoid signaling in 21-hydroxylase deficiency

Abstract

21-Hydroxylase deficiency (21OHD) is a rare genetic disorder in which salt-wasting syndrome occurs in 75% of cases, due to inability to synthesize cortisol and aldosterone. Recent mass spectrometry progress allowed identification of 21-deoxysteroids, i.e., 17-hydroxyprogesterone (17OHP), 21-deoxycortisol (21DF), and 21-deoxycorticosterone (21DB). We hypothesized that they may interfere with mineralocorticoid signaling and fludrocortisone therapy in patients with congenital adrenal hyperplasia (CAH) without effective glucocorticoid replacement and ACTH suppression. Our goal was to quantify circulating 21-deoxysteroids in a pediatric cohort with CAH related to 21OHD and to examine their impact on mineralocorticoid receptor (MR) activation. Twenty-nine patients with salt-wasting phenotype were classified in two groups according to their therapeutic control. During routine follow-up, 17OHP, 21DF, 21DB, and cortisol levels were quantified by liquid chromatography with tandem mass spectrometry before hydrocortisone intake and 1 and 2.5 h following treatment administration. Luciferase reporter gene assays were performed on transfected HEK293T cells while in silico modeling examined structural interactions between these steroids within ligand-binding domain of MR. Plasma 17OHP, 21DF, and 21DB accumulate in uncontrolled patients reaching micromolar concentrations even after hydrocortisone intake. 21DF and 21DB act as partial MR agonists with antagonist features similar to 17OHP, consistent with altered anchoring to Asn770 and unfavorable contact with Ala773 in ligand-binding pocket of MR. Our results demonstrate a complex interaction between all accumulating 21-deoxysteroids in uncontrolled 21OHD patients and mineralocorticoid signaling and suggest that appropriate steroid profiling should optimize management and follow-up of such patients, as keeping those steroids to low plasma levels should attest therapeutic efficacy and prevent interference with MR signaling.

Congenital adrenal Hyperplasia and psychosocial repercussions

“…Different studies correlate prenatal exposure to androgens with these changes in the identity of affected individuals, determining a higher incidence of GD, in addition to direct disturbances on neurodevelopment or psychosocial development 6,7,14,15,16 . Mechanism that facilitates the determination of gender has not yet been fully elucidated.…”

“…It is believed that, added to intrauterine fetal brain masculinization, a similar change occurs due to lack of adherence to glucocorticoid replacement therapy, during childhood and adolescence. In these patients, GD usually manifests itself in early adolescence 6,7 .…”

“…Early diagnostic methods, such as 17-OHP dosage or molecular analysis of the CYP21A2 gene (in amniocytes or chorionic villi), during the eighth week of gestation 3 , can be useful to avoid genital ambiguity in females and, also, precocious pseudopuberty in males. It is useful in preventing deaths resulting from the PS form 6,7 Less common variations of CAH (10% of cases) can present other disorders ,depending on the affected enzyme, such as Systemic Arterial Hypertension (SAH), no development of secondary sexual characters, low levels of androgens, signs of little or absent virilization in boys, hypergonadotrophic hypogonadism, history of maternal virilization during pregnancy and skeletal malformations. Definitive differential diagnosis of these forms, in relation to 21-OH deficiency, are made through specific genetic tests 3 .…”

“…Furthermore, insufficient glucocorticoid therapy can lead to excessive androgens, infertility and the development of adrenal crest tumors, making it a challenge for clinical practice to control the balance in treating these factors 7 .…”

“…As for the aesthetic aspects, in situations where the external genitalia are altered, surgical intervention is necessary, usually in the first 12 to 18 months of life, in order to reduce psychosocial disturbances and allow a normal sexual life 7 . In some cases, more than one surgical interventions are necessary.…”