Comprehensive sex steroid profiling in multiple tissues reveals novel insights in sex steroid distribution in male mice

A comprehensive atlas of sex steroid distribution in multiple tissues is currently lacking and how circulating and tissue sex steroid levels correlate remains unknown. Here, we adapted and validated a gas chromatography-tandem mass spectrometry method for simultaneous measurement of testosterone (T), dihydrotestosterone (DHT), androstenedione, progesterone (Prog), estradiol, and estrone in mouse tissues. We then mapped the sex steroid pattern in 10 different endocrine, reproductive, and major body compartment tissues and serum of gonadal intact and orchiectomized (ORX) male mice. In gonadal intact males, high levels of DHT were observed in reproductive tissues, but also in white adipose tissue (WAT). A major part of the total body reservoir of androgens (T and DHT) and Prog was found in WAT. Serum levels of androgens and Prog were strongly correlated with corresponding levels in the brain while only modestly correlated with corresponding levels in WAT. After ORX, the levels of active androgens T and DHT decreased markedly while Prog levels in male reproductive tissues increased slightly. In ORX mice, Prog was by far the most abundant sex steroid, and again, WAT constituted the major reservoir of Prog in the body. In conclusion, we present a comprehensive atlas of tissue and serum concentrations of sex hormones in male mice, revealing novel insights in sex steroid distribution. Brain sex steroid levels are well reflected by serum levels and WAT constitutes a large reservoir of sex steroids in male mice. In addition, Prog is the most abundant sex hormone in ORX mice.

The broad phenotypic spectrum of 17α-hydroxylase/17,20-lyase (CYP17A1) deficiency: a case series

Context 17α-Hydroxylase/17,20-lyase deficiency (17OHD) caused by mutations in the CYP17A1 gene is a rare form of congenital adrenal hyperplasia typically characterised by cortisol deficiency, mineralocorticoid excess and sex steroid deficiency. Objective To examine the phenotypic spectrum of 17OHD by clinical and biochemical assessment and corresponding in silico and in vitro functional analysis. Design Case series. Patients and results We assessed eight patients with 17OHD, including four with extreme 17OHD phenotypes: two siblings presented with failure to thrive in early infancy and two with isolated sex steroid deficiency and normal cortisol reserve. Diagnosis was established by mass spectrometry-based urinary steroid profiling and confirmed by genetic CYP17A1 analysis, revealing homozygous and compound heterozygous sequence variants. We found novel (p.Gly111Val, p.Ala398Glu, p.Ile371Thr) and previously described sequence variants (p.Pro409Leu, p.Arg347His, p.Gly436Arg, p.Phe53/54del, p.Tyr60IlefsLys88X). In vitro functional studies employing an overexpression system in HEK293 cells showed that 17,20-lyase activity was invariably decreased while mutant 17α-hydroxylase activity retained up to 14% of WT activity in the two patients with intact cortisol reserve. A ratio of urinary corticosterone over cortisol metabolites reflective of 17α-hydroxylase activity correlated well with clinical phenotype severity. Conclusion Our findings illustrate the broad phenotypic spectrum of 17OHD. Isolated sex steroid deficiency with normal stimulated cortisol has not been reported before. Attenuation of 17α-hydroxylase activity is readily detected by urinary steroid profiling and predicts phenotype severity. Significance statement Here we report, supported by careful phenotyping, genotyping and functional analysis, a prismatic case series of patients with congenital adrenal hyperplasia due to 17α-hydroxylase (CYP17A1) deficiency (17OHD). These range in severity from the abolition of function, presenting in early infancy, and unusually mild with isolated sex steroid deficiency but normal ACTH-stimulated cortisol in adult patients. These findings will guide improved diagnostic detection of CYP17A1 deficiency.

Impact of Clomiphene Citrate on the Steroid Profile in Dysmetabolic Men with Low Testosterone Levels

Clomiphene citrate (CC) in male hypogonadism increases testosterone (T) and estrogen levels by stimulating pituitary gonadotropin release. Our group confirmed these hormonal changes in a randomized, cross-over, double-blind trial of CC versus placebo in addition to metformin, conducted in 21 obese dysmetabolic men with low T levels. However, we hypothesize that based on its mechanism of action, CC may directly or indirectly affect adrenal steroidogenesis. The aim of this sub-study was to better understand the changes in steroid levels and metabolism induced by CC treatment. We assessed 17α-hydroxypregnelone (17αOH-P5), dehydroepiandrosterone (DHEA), progesterone (P4), 17α-hydroxyprogesterone (17αOH-P4), androstenedione (A), T, dihydrotestosterone (DHT), estrone (E1), 17β-estradiol (E2), 11-deoxycortisol (11 S), cortisol (F), and cortisone (E) by LC-MS/MS, and corticosteroid binding globulin (CBG) by ELISA, before and after each treatment. In addition, free-F and steroid product/precursor ratios were calculated. We observed a significant change in serum levels induced by CC compared with placebo for 17αOH-P4, DHT, T, E2, E1, F, E, and CBG, but not free-F. In addition, compared to placebo, CC induced higher 17αOH-P4/P4, E2/E1, 17αOH-P4/17αOH-P5, A/17αOH-P4, T/A, E1/A, F/11 S, and F/E ratios. Therefore, besides the CC stimulating effect on testis steroidogenesis, our study showed increased F, E, but not free-F, levels, indicating changes in steroid metabolism rather than adrenal secretion stimulation. The steroid profiling also revealed the CC stimulation of the Δ5 rather than the Δ4 pathway, thus indicating considerable testicular involvement in the increased androgen secretion.

ACTH Stimulation Maximizes the Accuracy of Peripheral Steroid Profiling in Primary Aldosteronism Subtyping

Background ACTH can contribute to aldosterone excess in primary aldosteronism (PA) via increased melanocortin type 2 receptor expression. Dynamic manipulation of the hypothalamic-pituitary-adrenal axis could assist PA subtyping, but a direct comparison of dynamic tests is lacking. Methods We conducted comprehensive dynamic testing in 80 patients: 40 with aldosterone-producing adenoma (APA) and 40 bilateral PA (BPA). Peripheral plasma was collected from each patient at 6 time-points: morning; midnight; after 1 mg dexamethasone suppression; and 15, 30, and 60 minutes after ACTH stimulation. We quantified 17 steroids by mass spectrometry in response to ACTH variations in all patients, and compared their discriminative power between the two PA subtypes. Results Patients with APA had higher morning and midnight concentrations of 18-hydroxycortisol, 18-oxocortisol, aldosterone, and 18-hydroxycorticosterone than those with BPA (p<0.001 for all). In response to cosyntropin stimulation, the APA group had larger increments of aldosterone, 18-oxocortisol, 11-deoxycorticosterone, corticosterone, and 11-deoxycortisol (p<0.05 for all). Following dexamethasone suppression, the APA group had larger decrements of aldosterone, 18-hydroxycortisol, and 18-oxocortisol (p<0.05 for all), but their concentrations remained higher than in the BPA group (p<0.01 for all). The highest discriminatory performance between the PA subtypes was achieved using steroids measured 15 minutes post-ACTH stimulation (area under receiver operating characteristic curve 0.957). Conclusion Steroid differences between APA and BPA are enhanced by dynamic hypothalamic-pituitary-adrenal testing; such non-invasive tests could circumvent the need for adrenal vein sampling in a subset of patients with PA.