Discriminatory Value of Steroid Hormones on Polycystic Ovary Syndrome and Clustering of Hyperandrogenism and Metabolic Factors.

OBJECTIVE: We determined (1) if 11-oxygenated androgens better identify polycystic ovary syndrome (PCOS) diagnosis in women with obesity compared to total or free testosterone (T) and free androgen index; (2) how biochemical hyperandrogenism and metabolic factors cluster in a cohort of women with infertility and obesity. METHODS: Women with obesity and PCOS comprised the study group (N = 132). Ovulatory women with obesity and idiopathic, tubal or male factor infertility were the control group (N = 83). Steroid hormones were measured by means of liquid chromatography tandem mass spectrometry. Receiver operating characteristic curves and principal component analysis were used. RESULTS: Women with obesity and PCOS had higher 11-ketotestosterone (11 KT) (1.22 nmol/L [0.84; 1.65] vs 1.05 [0.78; 1.35], P = .04) compared to controls, but not 11ß-hydroxyandrostenedione 4.30 [2.87; 5.92] vs 4.06 [3.22; 5.73], P = .44). 11-ketotestosterone (area under the curve: 0.59) did not better discriminate PCOS in women with obesity compared to: total T (0.84), free T (0.91), and free androgen index (0.85). We identified 4 principal components (PCs) in the PCOS group (72.1% explained variance): (1) insulin resistance status; (2) blood pressure; (3) obesity; (4) androgen status and 4 PCs in the control group (68.7% explained variance) with variables representing metabolism being dispersed in component 2, 3, and 4. CONCLUSIONS: Eleven-oxygenated androgens do not aid in the diagnosis of PCOS in women with obesity. Insulin resistance is the strongest PC in the PCOS group. There is no major dominant characteristic that defines obese non-PCOS women.

Report from the HarmoSter study: different LC-MS/MS androstenedione, DHEAS and testosterone methods compare well; however, unifying calibration is a double-edged sword.

OBJECTIVES: Current liquid chromatography-tandem mass spectrometry (LC-MS/MS) applications for circulating androgen measurements are technically diverse. Previously, variable results have been reported for testosterone. Data are scarce for androstenedione and absent for dehydroepiandrosterone sulfate (DHEAS). We assessed the agreement of androstenedione, DHEAS and testosterone LC-MS/MS measurements among nine European centers and explored benefits of calibration system unification. METHODS: Androgens were measured twice by laboratory-specific procedures in 78 patient samples and in EQA materials. Results were obtained by in-house and external calibration. Intra- and inter-laboratory performances were valued. RESULTS: Intra-laboratory CVs ranged between 4.2-13.2 % for androstenedione, 1.6-10.8 % for DHEAS, and 4.3-8.7 % and 2.6-7.1 % for female and male testosterone, respectively. Bias and trueness in EQA materials were within ±20 %. Median inter-laboratory CV with in-house vs. external calibration were 12.0 vs. 9.6 % for androstenedione (p<0.001), 7.2 vs. 4.9 % for DHEAS (p<0.001), 6.4 vs. 7.6 % for female testosterone (p<0.001) and 6.8 and 7.4 % for male testosterone (p=0.111). Median bias vs. all laboratory median with in-house and external calibration were -13.3 to 20.5 % and -4.9 to 18.7 % for androstenedione, -10.9 to 4.8 % and -3.4 to 3.5 % for DHEAS, -2.7 to 6.5 % and -11.3 to 6.6 % for testosterone in females, and -7.0 to 8.5 % and -7.5 to 11.8 % for testosterone in males, respectively. CONCLUSIONS: Methods showed high intra-laboratory precision but variable bias and trueness. Inter-laboratory agreement was remarkably good. Calibration system unification improved agreement in androstenedione and DHEAS, but not in testosterone measurements. Multiple components, such as commutability of calibrators and EQA materials and internal standard choices, likely contribute to inter-laboratory variability.

Salivary androgens in adolescence and their value as a marker of puberty: results from the SCAMP cohort.

Context: Salivary androgens represent non-invasive biomarkers of puberty that may have utility in clinical and population studies. Objective: To understand normal age-related variation in salivary sex steroids and demonstrate their correlation to pubertal development in young adolescents. Design, setting and participants: School-based cohort study of 1495 adolescents at two time points for collecting saliva samples approximately 2 years apart. Outcome measures: The saliva samples were analyzed for five androgens (testosterone, androstenedione (A4), 17-hydroxyprogesterone, 11-ketotestosterone and 11ß-hydroxyandrostenedione) using liquid chromatography-mass spectrometry; in addition, salivary dehydroepiandrosterone (DHEA) and oestradiol (OE2) were analysed by ELISA. The pubertal staging was self-reported using the Pubertal Development Scale (PDS). Results: In 1236 saliva samples from 903 boys aged between 11 and 16 years, salivary androgens except DHEA exhibited an increasing trend with an advancing age (ANOVA, P < 0.001), with salivary testosterone and A4 concentration showing the strongest correlation (r = 0.55, P < 0.001 and r = 0.48, P < 0.001, respectively). In a subgroup analysis of 155 and 63 saliva samples in boys and girls, respectively, morning salivary testosterone concentrations showed the highest correlation with composite PDS scores and voice-breaking category from PDS self-report in boys (r = 0.75, r = 0.67, respectively). In girls, salivary DHEA and OE2 had negligible correlations with age or composite PDS scores. Conclusion: In boys aged 11-16 years, an increase in salivary testosterone and A4 is associated with self-reported pubertal progress and represents valid non-invasive biomarkers of puberty in boys.

Tissue Glucocorticoid Metabolism in Adrenal Insufficiency: A Prospective Study of Dual-release Hydrocortisone Therapy.

BACKGROUND: Patients with adrenal insufficiency (AI) require life-long glucocorticoid (GC) replacement therapy. Within tissues, cortisol (F) availability is under the control of the isozymes of 11ß-hydroxysteroid dehydrogenase (11ß-HSD). We hypothesize that corticosteroid metabolism is altered in patients with AI because of the nonphysiological pattern of current immediate release hydrocortisone (IR-HC) replacement therapy. The use of a once-daily dual-release hydrocortisone (DR-HC) preparation, (Plenadren®), offers a more physiological cortisol profile and may alter corticosteroid metabolism in vivo. STUDY DESIGN AND METHODS: Prospective crossover study assessing the impact of 12 weeks of DR-HC on systemic GC metabolism (urinary steroid metabolome profiling), cortisol activation in the liver (cortisone acetate challenge test), and subcutaneous adipose tissue (microdialysis, biopsy for gene expression analysis) in 51 patients with AI (primary and secondary) in comparison to IR-HC treatment and age- and BMI-matched controls. RESULTS: Patients with AI receiving IR-HC had a higher median 24-hour urinary excretion of cortisol compared with healthy controls (72.1 µg/24 hours [IQR 43.6-124.2] vs 51.9 µg/24 hours [35.5-72.3], P = .02), with lower global activity of 11ß-HSD2 and higher 5-alpha reductase activity. Following the switch from IR-HC to DR-HC therapy, there was a significant reduction in urinary cortisol and total GC metabolite excretion, which was most significant in the evening. There was an increase in 11ß-HSD2 activity. Hepatic 11ß-HSD1 activity was not significantly altered after switching to DR-HC, but there was a significant reduction in the expression and activity of 11ß-HSD1 in subcutaneous adipose tissue. CONCLUSION: Using comprehensive in vivo techniques, we have demonstrated abnormalities in corticosteroid metabolism in patients with primary and secondary AI receiving IR-HC. This dysregulation of pre-receptor glucocorticoid metabolism results in enhanced glucocorticoid activation in adipose tissue, which was ameliorated by treatment with DR-HC.

Serum cortisol assay performance following the 1 mg overnight dexamethasone suppression test.

BACKGROUND: The 1 mg overnight dexamethasone suppression test (ONDST) is recommended for the differential diagnosis of Cushing's syndrome and the investigation of adrenal incidentalomas. Despite documented variation in serum cortisol immunoassay performance, little has been published regarding its effect on the ONDST. AIMS: Assess the performance of three immunoassay platforms (Roche Elecsys II, Abbott Alinity & Siemens Centaur) when compared to a liquid chromatography tandem mass spectrometry (LC-MS/MS) method. METHODS: Samples (n = 77) sent to the laboratory as part of an ONDST were retrieved prior to disposal, anonymized, and analysed on all platforms. Samples with factors impacting immunoassay analysis quality were excluded. Results were statistically compared to an LC-MS/MS method that previously demonstrated excellent comparability to a candidate reference method. RESULTS: The Roche gen II showed a mean bias of -2.4 nmol/L and a Passing-Bablok fit of y = -0.9 + 0.97x. This was not affected by sex. The Abbott showed a mean bias -18.8 nmol/L, and a fit of y = -11.3 + 0.88x. This bias was -20.7 nmol/L in females versus -17.2 nmol/L in males. The Siemens had a mean bias of 2.3 nmol/L and a fit of y = 1.4 + 1.07x. This bias was 5.7 nmol/L in males versus -1.0 nmol/L in females. CONCLUSIONS: Clinicians should be aware of the method-dependent variation that exists within serum cortisol analysis during the ONDSTs. Roche and Siemens aligned more closely with LC-MS/MS while the Abbot may cause a reduction in ONDST sensitivity. This data supports assay-specific cut-offs for the ONDST.

Classic and 11-oxygenated androgens in serum and saliva across adulthood: a cross-sectional study analyzing the impact of age, body mass index, and diurnal and menstrual cycle variation.

OBJECTIVE: 11-oxygenated androgens significantly contribute to the circulating androgen pool. Understanding the physiological variation of 11-oxygenated androgens and their determinants is essential for clinical interpretation, for example, in androgen excess conditions. We quantified classic and 11-oxygenated androgens in serum and saliva across the adult age and body mass index (BMI) range, also analyzing diurnal and menstrual cycle-dependent variation. DESIGN: Cross-sectional. Morning serum samples were collected from 290 healthy volunteers (125 men, 22-95 years; 165 women, 21-91 years). Morning saliva samples were collected by a sub-group (51 women and 32 men). Diurnal saliva profiles were collected by 13 men. Twelve women collected diurnal saliva profiles and morning saliva samples on 7 consecutive days during both follicular and luteal menstrual cycle phases. METHODS: Serum and salivary steroids were quantified by liquid chromatography-tandem mass spectrometry profiling assays. RESULTS: Serum classic androgens decreased with age-adjusted BMI, for example, %change kg/m2 for 5α-dihydrotestosterone: men -5.54% (95% confidence interval (CI) -8.10 to -2.98) and women -1.62% (95%CI -3.16 to -0.08). By contrast, 11-oxygenated androgens increased with BMI, for example, %change kg/m2 for 11-ketotestosterone: men 3.05% (95%CI 0.08-6.03) and women 1.68% (95%CI -0.44 to 3.79). Conversely, classic androgens decreased with age in both men and women, while 11-oxygenated androgens did not. Salivary androgens showed a diurnal pattern in men and in the follicular phase in women; in the luteal phase, only 11-oxygenated androgens showed diurnal variation. CONCLUSIONS: Classic androgens decrease while active 11-oxygenated androgens increase with increasing BMI, pointing toward the importance of adipose tissue mass for the activation of 11-oxygenated androgens. Classic but not 11-oxygenated androgens decline with age.

11-Oxygenated androgens are not secreted by the human ovary: in-vivo data from four different cases of hyperandrogenism.

Objective: Differentiation of an adrenal from an ovarian source of hyperandrogenemia can be challenging. Recent studies have highlighted the importance of 11-oxygenated C19 steroids to the androgen pool in humans. The aim of this study was to confirm the origin of 11-oxygenated androgens in females and to explore their potential use in the diagnostics of hyperandrogenic disorders. Methods: We measured testosterone and its precursors (dehydroepiandrosterone-sulfate and androstenedione) and 11-oxygenated androgens (11ß-hydroxyandrostenedione (11-OHA4) and 11-ketotestosterone (11-KT)) in the periphery, adrenal and ovarian veins in four different cases of hyperandrogenism in females (polycystic ovary syndrome (PCOS), primary bilateral macronodular adrenal hyperplasia, Sertoli-Leydig cell tumor and ovarian steroid cell tumor). Results: Two patients demonstrate excessive testosterone secretion in neoplastic ovarian tumors which was not paralleled by a significant secretion of 11-oxygenated androgens as determined by adrenal and ovarian vein sampling. In androgen-secreting bilateral adrenal macronodular hyperplasia, steroid profiles were characterized by elevated 11-KT and 11-OHA4 concentrations in adrenal veins and the periphery. In the patient with PCOS, peripheral 11-KT concentrations were slightly elevated in comparison to the other patients, but the 11-KT and 11-OHA4 concentrations were comparable in ovarian veins and in the periphery. Conclusion: This study confirms that 11-OHA4 and 11-KT are not biosynthesized by the ovary. We propose that the testosterone/11-KT ratio as well as 11-OHA4 could help identify predominant adrenal androgen excess and distinguish neoplastic and non-neoplastic ovarian androgen source. Significance statement: This study confirms that 11ß-hydroxyandrostenedione (11-OHA4) and 11-ketotestosterone (11-KT) are not biosynthesized by the human ovary. We propose that the testosterone/11-KT ratio as well as 11-OHA4 could help to identify predominant adrenal androgen excess and distinguish neoplastic and non-neoplastic ovarian androgen source.

Multi-steroid profiling by UHPLC-MS/MS with post-column infusion of ammonium fluoride.

BACKGROUND: Multi-steroid profiling is a powerful analytical tool that simultaneously quantifies steroids from different biosynthetic pathways. Here we present an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) assay for the profiling of 23 steroids using post-column infusion of ammonium fluoride. METHODS: Following liquid-liquid extraction, steroids were chromatographically separated over 5 min using a Phenomenex Luna Omega C18 column and a water (0.1 % formic acid) methanol gradient. Quantification was performed on a Waters Acquity UHPLC and Xevo® TQ-XS mass spectrometer. Ammonium fluoride (6 mmol/L, post-column infusion) and formic acid (0.1 % (vol/vol), mobile phase additive) were compared as additives to aid ionisation. RESULTS: Post-column infusion of ammonium fluoride enhanced ionisation in a steroid structure-dependent fashion compared to formic acid (122-140 % for 3ßOH-Δ5 steroids and 477-1274 % for 3-keto-Δ4 steroids). Therefore, we analytically validated post-column infusion of ammonium fluoride. Lower limits of quantification ranged from 0.3 to 3 nmol/L; All analytes were quantifiable with acceptable accuracy (bias range -14 % to 11.9 % for 21/23, -21 % to 11.9 % for all analytes). Average recovery ranged from 91.6 % to 113.6 % and average matrix effects from -29.9 % to 19.9 %. Imprecision ranged from 2.3 % to 23 % for all analytes and was < 15 % for 18/23 analytes. The serum multi-steroid profile of 10 healthy men and 10 healthy women was measured. CONCLUSIONS: UHPLC-MS/MS with post-column infusion of ammonium fluoride enables comprehensive multi-steroid profiling through enhanced ionisation particularly benefiting the detection of 3-keto-Δ4 steroids.

Salivary Steroid Collection in Children Under Conditions Replicating Home Sampling.

CONTEXT: Measurement of salivary glucocorticoids is an accepted method for testing adrenal function but there are few data on stability during home collection. Current salivary collection techniques require active participation or present a choking hazard and are unsuitable for young children. OBJECTIVE: We sought to compare different salivary collection methods; assess the stability of salivary glucocorticoids under conditions replicating home collection; and assess patient tolerability and caregiver acceptability of a salivary collection device for young children, a swab encased in an infant pacifier (SaliPac). METHODS: Six healthy adults collected salivary samples using a Salivette Cortisol, passive drool, and SalivaBio at night, waking, and 3 Pm for five days. Time to collect 1-mL saliva using the SalivaBio and SaliPac and caregiver acceptability were assessed in 30 children younger than 6 years. Saliva was stored at 4 °C, room temperature (RT), and 50 °C for 24, 48, 72 hours and 1 week to replicate potential postage conditions. Salivary cortisol and cortisone concentrations were measured by mass spectrometry. RESULTS: There was no difference in salivary glucocorticoid concentrations using the 3 collection methods. Salivary cortisol and cortisone were stable for 72 hours at RT and 4 °C, and repeated freeze-thaw cycles did not cause significant degradation. In children younger than 6 years the SalivaBio and SaliPac were well tolerated and collected sufficient saliva for salivary steroid analysis in less than 4 minutes. CONCLUSION: Salivette, passive drool, and SalivaBio collect samples with comparable salivary cortisol and cortisone concentrations, which are stable under conditions replicating home collection. SaliPac is an acceptable device for salivary sampling in young children.

Report from the HarmoSter study: impact of calibration on comparability of LC-MS/MS measurement of circulating cortisol, 17OH-progesterone and aldosterone.

OBJECTIVES: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is recommended for measuring circulating steroids. However, assays display technical heterogeneity. So far, reproducibility of corticosteroid LC-MS/MS measurements has received scant attention. The aim of the study was to compare LC-MS/MS measurements of cortisol, 17OH-progesterone and aldosterone from nine European centers and assess performance according to external quality assessment (EQA) materials and calibration. METHODS: Seventy-eight patient samples, EQA materials and two commercial calibration sets were measured twice by laboratory-specific procedures. Results were obtained by in-house (CAL1) and external calibrations (CAL2 and CAL3). We evaluated intra and inter-laboratory imprecision, correlation and agreement in patient samples, and trueness, bias and commutability in EQA materials. RESULTS: Using CAL1, intra-laboratory CVs ranged between 2.8-7.4%, 4.4-18.0% and 5.2-22.2%, for cortisol, 17OH-progesterone and aldosterone, respectively. Trueness and bias in EQA materials were mostly acceptable, however, inappropriate commutability and target value assignment were highlighted in some cases. CAL2 showed suboptimal accuracy. Median inter-laboratory CVs for cortisol, 17OH-progesterone and aldosterone were 4.9, 11.8 and 13.8% with CAL1 and 3.6, 10.3 and 8.6% with CAL3 (all p<0.001), respectively. Using CAL1, median bias vs. all laboratory-medians ranged from -6.6 to 6.9%, -17.2 to 7.8% and -12.0 to 16.8% for cortisol, 17OH-progesterone and aldosterone, respectively. Regression lines significantly deviated from the best fit for most laboratories. Using CAL3 improved cortisol and 17OH-progesterone between-method bias and correlation. CONCLUSIONS: Intra-laboratory imprecision and performance with EQA materials were variable. Inter-laboratory performance was mostly within specifications. Although residual variability persists, adopting common traceable calibrators and RMP-determined EQA materials is beneficial for standardization of LC-MS/MS steroid measurements.

Low competitive status elicits aggression in healthy young men: behavioural and neural evidence.

Winners are commonly assumed to compete more aggressively than losers. Here, we find overwhelming evidence for the opposite. We first demonstrate that low-ranking teams commit more fouls than they receive in top-tier soccer, ice hockey and basketball men's leagues. We replicate this effect in the laboratory, showing that male participants deliver louder sound blasts to a rival when placed in a low-status position. Using neuroimaging, we characterize brain activity patterns that encode competitive status as well as those that facilitate status-dependent aggression in healthy young men. These analyses reveal three key findings. First, anterior hippocampus and striatum contain multivariate representations of competitive status. Second, interindividual differences in status-dependent aggression are linked with a sharper status differentiation in the striatum and with greater reactivity to status-enhancing victories in the dorsal anterior cingulate cortex. Third, activity in ventromedial, ventrolateral and dorsolateral prefrontal cortex is associated with trial-wise increases in status-dependent aggressive behaviour. Taken together, our results run counter to narratives glorifying aggression in competitive situations. Rather, we show that those in the lower ranks of skill-based hierarchies are more likely to behave aggressively and identify the potential neural basis of this phenomenon.

An LC-MS/MS assay for analysis of equilibrium angiotensin II in human serum.

BACKGROUND: The current first-line screening test for primary hyperaldosteronism is the plasma aldosterone:renin ratio; however, renin assays have several disadvantages and the ARR is affected by medications and physiological factors. Angiotensin II is a key biologically active hormone in the renin-angiotensin-aldosterone system. It has been suggested that measurement of equilibrium levels of this peptide, involving an in vitro incubation of serum prior to analysis, may provide a better marker of renin-angiotensin-aldosterone system activity than renin. METHODS: An eqAng II LC-MS/MS assay was developed, optimized and validated. Serum samples were incubated at 37°C for 45 min prior to stabilization with cold EDTA solution, solid phase extraction and LC-MS/MS analysis. Stability in whole blood and the effect of cryoactivation were assessed. For comparison to the current screening test, 150 anonymized patients' samples were analysed for eqAng II, renin activity and aldosterone (all by LC-MS/MS). RESULTS: The assay had good precision, minimal bias and acceptable recovery. EqAng II did not change significantly when whole blood samples were stored for up to 72 h, and cryoactivation was only observed for pregnant patients. EqAng II was significantly correlated with renin, and the aldosterone:eqAng II ratio had a strong positive correlation with the aldosterone:renin ratio. CONCLUSIONS: An LC-MS/MS assay for eqAng II has been developed which shows promise as an alternative screening test for primary hyperaldosteronism. Compared to renin assays, it is quicker, simpler and less likely to be affected by anti-hypertensive medications. Further clinical validation in hypertensive patients would be required prior to implementation.

Modifying dietary patterns in cardiothoracic transplant patients to reduce cardiovascular risk: The AMEND-IT Trial.

BACKGROUND: Cardiovascular disease (CVD) is common after cardiothoracic transplantation and causes substantial morbidity. AIMS: To assess feasibility and potential effectiveness of dietary interventions to reduce CVD risk. MATERIALS AND METHODS: In a pilot intervention, we recruited patients from a tertiary hospital and randomly allocated them to a Mediterranean or low-fat diet for 12 months. Feasibility was measured by patient participation, retention, and adherence. Changes in weight, body mass index (BMI), heart rate, blood pressure, glucose markers, and blood lipids were assessed using longitudinal generalized estimating equation regression models with 95% confidence intervals. RESULTS: Of 56 heart and 60 lung transplant recipients, 52 (45%) consented, 41 were randomized, and 39 (95%) completed the study with good adherence to randomized diets. After 12 months, changes in many risk factors were seen in the Mediterranean and low-fat-diet groups, respectively, including mean BMI (-0.5 vs. 0.0 kg/m2 ), systolic/diastolic blood pressure +0.5/+0.1 vs -4.4/-3.5 mmHg; fasting glucose -0.26 vs -0.27 mmol/L; total cholesterol -0.56 vs -0.40 mmol/L. Changes in BMI and systolic/diastolic blood pressure in 49 eligible patients who did not take part were +0.7 kg/m2 and +2.5/+1.8 mmHg. DISCUSSION: Dietary interventions in cardiothoracic transplant patients are feasible and potentially beneficial. CONCLUSION: A definitive nutritional intervention study in these high-risk patients is warranted.

The contribution of serum cortisone and glucocorticoid metabolites to detrimental bone health in patients receiving hydrocortisone therapy.

BACKGROUND: Glucocorticoid therapy is the most common cause of iatrogenic osteoporosis. Less is known regarding the effect of glucocorticoids when used as replacement therapy on bone remodelling in patients with adrenal insufficiency. Enhanced intracellular conversion of inactive cortisone to active cortisol, by 11 beta-hydroxysteroid dehydrogenase type 1(11ß-HSD1) and other enzymes leading to alterations in glucocorticoid metabolism, may contribute to a deleterious effect on bone health in this patient group. METHODS: Study design: An open crossover prospective study randomizing ten hypopituitary men, with severe ACTH deficiency, to three commonly used hydrocortisone dose regimens. MEASUREMENTS: Following 6 weeks of each regimen, patients underwent 24-h serum cortisol/cortisone sampling, measurement of bone turnover markers, and a 24-h urine collection for measurement of urinary steroid metabolites by gas chromatography-mass spectrometry (GC-MS). Serum cortisone and cortisol were analysed by liquid chromatography-mass spectrometry (LC-MS). RESULTS: Dose-related and circadian variations in serum cortisone were seen to parallel those for cortisol, indicating conversion of ingested hydrocortisone to cortisone. The median area under the curve (AUC) of serum cortisone was significantly higher in patients on dose A (20 mg/10 mg) [670.5 (IQR 621-809.2)] compared to those on dose C (10 mg/5 mg) [562.8 (IQR 520.1-619.6), p = 0.01]. A negative correlation was observed between serum cortisone and bone formation markers, OC [1-49] (r = - 0.42, p = 0.03), and PINP (r = - 0.49, p = 0.01). There was a negative correlation between the AUC of night-time serum cortisone levels with the bone formation marker, OC [1-49] (r = - 0.41, p = 0.03) but there were no significant correlations between day-time serum cortisone or cortisol with bone turnover markers. There was a negative correlation between total urinary cortisol metabolites and the bone formation markers, PINP (r = - 0.39, p = 0.04), and OC [1-49] (r = - 0.35, p = 0.06). CONCLUSION: Serum cortisol and cortisone and total urinary corticosteroid metabolites are negatively associated with bone turnover markers in patients receiving replacement doses of hydrocortisone, with nocturnal glucocorticoid exposure having a potentially greater influence on bone turnover. TRIAL REGISTRATION: Irish Medicines Board Clinical Trial Number - CT900/459/1 and EudraCT Number - 2007-005018-37 . Registration date: 07-09-2007.

Intracrine Testosterone Activation in Human Pancreatic ß-Cells Stimulates Insulin Secretion.

Testosterone (T) affects ß-cell function in men and women. T is a prohormone that undergoes intracrine conversion in target tissues to the potent androgen dihydrotestosterone (DHT) via the enzyme 5α-reductase (5α-R) or to the active estrogen 17ß-estradiol (E2) via the aromatase enzyme. Using male and female human pancreas sections, we show that the 5α-R type 1 isoform (SRD5A1) and aromatase are expressed in male and female ß-cells. We show that cultured male and female human islets exposed to T produce DHT and downstream metabolites. In these islets, exposure to the 5α-R inhibitors finasteride and dutasteride inhibited T conversion into DHT. We did not detect T conversion into E2 from female islets. However, we detected T conversion into E2 in islets from two out of four male donors. In these donors, exposure to the aromatase inhibitor anastrozole inhibited E2 production. Notably, in cultured male and female islets, T enhanced glucose-stimulated insulin secretion (GSIS). In these islets, exposure to 5α-R inhibitors or the aromatase inhibitor both inhibited T enhancement of GSIS. In conclusion, male and female human islets convert T into DHT and E2 via the intracrine activities of SRD5A1 and aromatase. This process is necessary for T enhancement of GSIS.

Assessment of tacrolimus and creatinine concentration collected using Mitra microsampling devices.

BACKGROUND: Current practice requires regular venous blood samples for monitoring of tacrolimus concentrations post renal transplant requiring regular hospital visits. Mitra devices use volumetric absorptive microsampling technology and absorb a fixed amount of blood (10 µL) from a capillary blood sample. They are a viable volumetric alternative to dried blood spots and are able to be posted to the laboratory for analysis. OBJECTIVE: The aim was to develop and validate liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays for tacrolimus and creatinine analysis using Mitra devices. The usefulness of this approach was assessed in renal transplant patients routinely monitored for tacrolimus and creatinine. METHOD: Routine tacrolimus samples were used to assess the utility and reliability of Mitra sampling. Shared sample preparation for both tacrolimus and creatinine was carried out in a 96-deep well plate; mass spectrometric analysis was then undertaken for tacrolimus followed by re-injection for creatinine analysis. RESULTS: Comparison of 131 Mitra samples with a routine LC-MS/MS assay for tacrolimus showed a minimal bias -5.6% (95% CI -8.5 to -2.7%). Comparison of 135 serum and Mitra samples for creatinine using a fully validated LC-MS/MS assay showed a bias -6.5% (95% CI -8.5 to -4.5%). DISCUSSION: We have developed assays for tacrolimus and creatinine on fingerprick blood using the Mitra device and believe this approach provides a viable alternative to repeated venepuncture for therapeutic drug monitoring. This method could open up the opportunity for patients to perform tacrolimus and kidney function monitoring at home.