Profiling of urinary steroids aided by lithium ion adduction-based ultrahigh-performance liquid chromatography-tandem mass spectrometry.

RATIONALE: As 3-OH-containing steroids are prone to dehydration by conventional electrospray ionization, reducing detection sensitivity, Li ion adduction-based ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC/MS/MS), developed to prevent dehydration and effectively detect 3-OH steroids, was applied for profiling total and free steroids in urine. METHODS: Free urinary steroids were isolated directly from urine by solid-phase extraction (SPE) with 80% acetonitrile. The total steroids were prepared by enzymatic treatment of urine with a cocktail of sulfatase and glucronidase, protein precipitation, and separation with the above SPE. In order to detect as many steroid types as possible, UHPLC/MS/MS (Li method) with Li+ solution added after the column was used for analysis in addition to the conventional method of detecting protonated ions (H method). The 13 3-OH steroids and the remaining 16 steroids were quantified by standard curves prepared using product ion transitions derived from [M + Li]+ and MH+ , respectively. RESULTS: Two groups of human urine, male and female urine, were analyzed. 3-OH steroids could be detected with greater sensitivity using the Li method than the conventional method. The absolute amounts of each steroid were normalized based on creatinine levels. The difference between the male and female groups are clearly attributable to sex steroids. CONCLUSIONS: Twenty-nine total steroids and 19 free steroids were identified in a limited volume (240 mL) of urine. Of these, 13 3-OH steroids were better detected by Li+ adduction-based UHPLC/MS/MS.

Influence of multiple human chorionic gonadotropin administrations on serum and urinary steroid Athlete Biological Passport profiles in males.

The Athlete Biological Passport (ABP) is a longitudinal tool used in anti-doping to monitor biological parameters known to change with performance-enhancing drug use. The ABP consists of multiple modules, including two aimed at detecting the use of endogenous anabolic androgenic steroids: the urinary and serum steroid modules. Human chorionic gonadotropin (hCG) is a protein hormone potentially abused by male athletes to increase the production of endogenous testosterone. To date, no studies have investigated the impact of extended hCG administration on the urinary and serum steroid modules of the ABP. The goal of this study was to identify the impact of multiple hCG administrations on the parameters tracked as part of the urinary and serum steroid modules of the ABP. Ten recreationally active, healthy male individuals self-administered seven 250 µg hCG injections over 3 weeks. Serum and urine samples were collected before, during, and 2 weeks following the final injection. All ABP parameters were quantified in the respective matrix, and steroid profiles were created with Anti-Doping Administration and Management System adaptive model upper and lower limits for both matrices. In both serum and urine profiles, testosterone increased; however, the testosterone/epitestosterone ratio in urine and the testosterone/androstenedione ratio in serum showed minimal changes. Additionally, serum luteinizing hormone (LH) was quantified using an immunoassay, and a serum testosterone/LH ratio was generated. Serum LH values decreased during administration causing large increases in the serum T/LH ratio, indicating this ratio may be a more sensitive parameter for detecting hCG abuse than urinary testosterone/epitestosterone or serum testosterone/androstenedione.

Effect of thyroid hormones administration on urinary endogenous steroid profile of the athlete biological passport.

This work focused on the possible alterations of the markers of the steroidal module of the athlete biological passport, considering samples of athletes declaring and not-declaring the supplementation of thyroid hormones (TH) in the Doping Control Form (DCF). Concentrations of 5α-androstane-3α,17ß-diol (5α-Adiol), 5ß-androstane-3α,17ß-diol (5ß-Adiol), testosterone (T), androsterone (A), etiocholanolone (Etio), epitestosterone (E), pregnanediol (PD), dehydroepiandrosterone (DHEA), and 11ß-hydroxy-androsterone (OHA) were calculated using internal standards and external calibration by gas chromatography-tandem mass spectrometry. Also, ratios between the above biomarkers were also estimated. The data set was composed of samples from females and males declaring and not-declaring TH supplementation in the DCF. To corroborate these observations, a controlled urinary excretion study was carried out with multiple doses of sodium liothyronine (T3). Female data showed significant differences for the concentrations of 5α-Adiol, A, DHEA, E, OHA, and T and the ratio A/Etio between FD and FND groups, whereas the male groups only showed significant differences in OHA concentration. In both cases, males and females declaring the consumption of levothyroxine showed narrower data distribution and diminished percentiles from 17% to 67% with respect to the not-declaring corresponding groups (p < 0.05). Concentrations of 5α-metabolites showed a higher depression for the FND, and both FD and MD groups showed a peculiar behavior for the PD concentrations. The controlled study agreed with the observations, mainly for the female group with significant differences for concentrations of E, Etio, 5α-Adiol, and 5ß-Adiol after TH administration. The interpretation of the steroid markers of the ABP should consider TH administrations.

LC-HRMS-based metabolomics workflow: An alternative strategy for metabolite identification in the antidoping field.

RATIONALE: The proposed metabolomic workflow, based on coupling high-resolution mass spectrometry with computational tools, can be an alternative strategy for metabolite detection and identification. This approach allows the extension of the investigation field to chemically different compounds, maximizing the information obtainable from the data and minimizing the time and resources required. METHODS: Urine samples were collected from five healthy volunteers before and after oral administration of 3ß-hydroxyandrost-5-ene-7,17-dione as a model compound and defining three excretion time intervals. Raw data were acquired in both positive and negative ionization modes using an Agilent Technologies 1290 Infinity II series HPLC coupled to a 6545 Accurate-Mass Quadrupole Time-of-Flight. They were then processed to align peak retention times with the same accurate mass, and the resulting data matrix was subjected to multivariate analysis. RESULTS: Multivariate analysis (PCA and PLS-DA models) demonstrated high similarity between samples belonging to the same collection time interval and clear discrimination between different excretion intervals. The blank and long excretion groups were distinguished, suggesting the presence of long excretion markers, which are of remarkable interest in anti-doping analyses. The correspondence of some significant features with metabolites reported in the literature confirmed the rationale and usefulness of the proposed metabolomic approach. CONCLUSIONS: The presented study proposes a metabolomics workflow for the early detection and characterization of drug metabolites by untargeted urinary analysis to reduce the range of substances still excluded from routine screening. Its application has detected minor steroid metabolites, as well as unexpected endogenous alterations, proving to be an alternative strategy that can allow gathering a more complete range of information in the antidoping field.

A new multimodal paradigm for biomarkers longitudinal monitoring: a clinical application to women steroid profiles in urine and blood.

BACKGROUND: Most current state-of-the-art strategies to generate individual adaptive reference ranges are designed to monitor one clinical parameter at a time. An innovative methodology is proposed for the simultaneous longitudinal monitoring of multiple biomarkers. The estimation of individual thresholds is performed by applying a Bayesian modeling strategy to a multivariate score integrating several biomarkers (compound concentration and/or ratio). This multimodal monitoring was applied to data from a clinical study involving 14 female volunteers with normal menstrual cycles receiving testosterone via transdermal route, as to test its ability to detect testosterone administration. The study samples consisted of urine and blood collected during 4 weeks of a control phase and 4 weeks with a daily testosterone gel application. RESULTS: Integrating multiple biomarkers improved the detection of testosterone gel administration with substantially higher sensitivity compared with the distinct follow-up of each biomarker, when applied to selected urine and serum steroid biomarkers, as well as the combination of both. Among the 175 known positive samples, 38% were identified by the multimodal approach using urine biomarkers, 79% using serum biomarkers and 83% by combining biomarkers from both biological matrices, whereas 10%, 67% and 64% were respectively detected using standard unimodal monitoring. SIGNIFICANCE AND NOVELTY: The detection of abnormal patterns can be improved using multimodal approaches. The combination of urine and serum biomarkers reduced the overall number of false-negatives, thus evidencing promising complementarity between urine and blood sampling for doping control, as highlighted in the case of the use of transdermal testosterone preparations. The generation in a multimodal setting of adaptive and personalized reference ranges opens up new opportunities in clinical and anti-doping profiling. The integration of multiple parameters in a longitudinal monitoring is expected to provide a more complete evaluation of individual profiles generating actionable intelligence to further guide sample collection, analysis protocols and decision-making in clinics and anti-doping.

Intra-individual stability of longitudinal urinary steroid profiles in Swedish athletes.

The steroid module of the athlete biological passport (ABP) aims to detect doping with endogenous steroids by longitudinally monitoring epitestosterone (E), testosterone (T), and four metabolically related steroids and their ratios. There are large variations in the urinary levels of the androgen metabolites due to genetic polymorphisms, drug use, menstrual cycle, and other factors. In this study, we aimed to increase our understanding of the natural, within-individual variations of the established ABP markers in males and females over time, looking at samples collected both in and out-of-competition (IC/OOC). Urinary steroid profiles from 323 Swedish athletes, with at least five samples per athlete, were extracted from ADAMS together with information on type of sport, IC/OOC, and time of day. Data were analyzed using coefficient of variation (CV%) to examine within-subject variability and linear mixed effects models to estimate within-subject change in the metabolites over time. The metabolites and ratios expressed higher individual CV% in females (23-56) than in males (18-39). Samples taken OOC showed larger intra-individual variations than samples collected IC for most of the ABP metabolites in both sexes. The median concentrations were higher IC for some metabolites, particularly testosterone being 52% higher among females. Time of day influenced the intra-individual variation of the urinary steroid profile with decreases in androgen metabolites over time, if measured in evening versus daytime. These findings can aid in the testing strategies and interpretation of the steroidal module of ABP.

Metabotypes of congenital adrenal hyperplasia in infants determined by gas chromatography-mass spectrometry in spot urine.

Biochemical monitoring of treatment in infants with classic congenital adrenal hyperplasia (CAH) is not yet well defined. The aim of this study was to perform a cluster analysis of the urinary steroid metabolome for treatment monitoring of infants with classic salt-wasting CAH. We analyzed spot urine samples obtained from 60 young children ≤ 4 years of age (29 females) with classic CAH due to 21-hydroxylase deficiency treated with hydrocortisone and fludrocortisone by targeted gas chromatography-mass spectrometry (GC-MS). Patients were classified into different groups according to their metabolic patterns (metabotypes) using unsupervised k-means clustering algorithms. Three metabotypes could be discovered. Metabotype #1 (N = 15 (25%)) showed high concentrations of androgen and 17-hydroxyprogesterone (17OHP) precursor steroids, metabotype #2 (N = 28 (47%)) revealed balanced metabolic control, and metabotype #3 (N = 17; 28%) demonstrated severe adrenal suppression with low concentrations of androgen and 17OHP precursor steroids. Daily hydrocortisone doses and urinary concentrations of cortisol and cortisone metabolites did not differ between all three metabotypes. Metabotype #2 had highest daily dose of fludrocortisone (p = 0.006). Receiver operating characteristic curve analysis showed that 11-ketopregnanetriol (area under the curve [AUC] 0.967) and pregnanetriol (AUC 0.936) were most suitable of separating metabotype #1 from #2. For separation between metabotypes #2 vs. #3, the 11-oxygenated androgen metabolite 11-hydroxyandrosterone (AUC 0.983) and the ratio of 11-hydroxyandrosterone to tetrahydrocortisone (AUC 0.970) were most suitable. In conclusion, GC-MS-based urinary steroid metabotyping is a new method to help monitor the treatment of infants with CAH. This method allows classification of under-, over- and adequately treated young children.

Disposition of serum steroids in response to combined oral contraceptives and menstrual cycle phases: A double-blind, randomized, placebo-controlled study.

To analyze doping control samples from female athletes demands understanding of non-doping factors that affect the steroid profile. These could be physiological factors such as exercise, alcohol consumption, hormonal changes during the menstrual cycle, or the effect of commonly used approved drugs like combined oral contraceptives. Urine samples have been the main way of doping testing, but serum samples are proposed as a complement. Testosterone, dihydrotestosterone, or the ratio of testosterone and androstenedione has been proposed as a biomarker for testosterone doping because it increases after transdermal testosterone administration. In this double-blind, randomized, placebo-controlled study of 340 healthy females, we analyzed the serum steroid levels, including glucuronide metabolites, before and after 3 months of combined oral contraceptives or placebo. At follow up, sample collection in the placebo group was randomly distributed between different menstrual cycle phases. This enabled to analyze changes in concentrations between the follicular, ovulation, and luteal phases. Combined oral contraceptives decreased all serum steroids including the glucuronide metabolites. As expected, serum testosterone levels increased during the ovulation phase, and also androstenedione and androstenediol, whereas the glucuronide metabolites remained unaffected. Neither combined oral contraceptives nor menstrual cycle phases did affect the ratio of testosterone and androstenedione in serum, and consequently this ratio seems promising as a marker of doping with endogenous anabolic androgenic steroids in women.

Variability of the urinary and blood steroid profiles in healthy and physically active women with and without oral contraception.

The steroidal module of the athlete biological passport (ABP) targets the use of pseudo-endogenous androgenous anabolic steroids in elite sport by monitoring urinary steroid profiles. Urine and blood samples were collected weekly during two consecutive oral contraceptive pill (OCP) cycles in 15 physically active women to investigate the low urinary steroid concentrations and putative confounding effect of OCP. In urine, testosterone (T) and epitestosterone (E) were below the limit of quantification of 1 ng/ml in 62% of the samples. Biomarkers' variability ranged between 31% and 41%, with a significantly lesser variability for ratios (except for T/E [41%]): 20% for androsterone/etiocholanolone (p < 0.001) and 25% for 5α-androstane-3α,17ß-diol/5ß-androstane-3α,17ß-diol (p < 0.001). In serum, markers' variability (testosterone: 24%, androstenedione: 23%, dihydrotestosterone: 19%, and T/A4: 16%) was significantly lower than in urine (p < 0.001). Urinary A/Etio increased by >18% after the first 2 weeks (p < 0.05) following withdrawal blood loss. In contrast, serum T (0.98 nmol/l during the first week) and T/A4 (0.34 the first week) decreased significantly by more than 25% and 17% (p < 0.05), respectively, in the following weeks. Our results outline steroidal variations during the OCP cycle, highlighting exogenous hormonal preparations as confounder for steroid concentrations in blood. Low steroid levels in urine samples have a clear negative impact on the subsequent interpretation of steroid profile of the ABP. With a greater analytical sensitivity and lesser variability for steroids in healthy active women, serum represents a complementary matrix to urine in the ABP steroidal module.

Comparison of three different blood matrices for the quantification of endogenous steroids using UHPLC-MS/MS.

Urine is currently the matrix of choice for the detection of exogenous substances but also for the application of the steroidal module of the Athlete Biological Passport (ABP) consisting in a longitudinal monitoring of steroid biomarkers. To fill the limitations related to urine, the longitudinal monitoring of serum steroids concentration in the so-called 'blood steroid profile' has recently been proposed. Although serum samples are collected much less than urine samples, plasma derived from ABP whole blood samples used for the full blood count could be exploited for the quantification of endogenous steroids. Alternatively, dried blood spots (DBS) that are much easier to collect could also serve as matrix for the steroid profile. In this study, we compared the concentration levels of several endogenous steroids measured in three different blood matrices (serum, plasma and DBS) collected from 100 elite athletes participating in the 2019 Doha World Athletics Championships using UHPLC-MS/MS. Plasma and serum samples were collected by venipuncture, whereas DBS were generated from whole blood samples. Although steroids demonstrated a good agreement between the three matrices, a slight but acceptable underestimation (10%-20%) was observed in plasma compared with serum. The difference between DBS and the two other matrices was dependent of the bias between serum and plasma. We also showed that a generic HCT correction for DBS could be a valuable approach for quantitative measurements. This study demonstrates the possibility to use three different matrices for the quantification of endogenous steroids although the slight discrepancies should be considered for longitudinal evaluation.

Addressing recent challenges in isotope ratio mass spectrometry: Development of a method applicable to 1-androstene-steroids, 6α-hydroxy-androstenedione, and androstatrienedione.

In 2020, the confirmation of the non-endogenous origin of several pseudo-endogenous steroids by means of isotope ratio mass spectrometry (IRMS) was recommended by the World Anti-Doping Agency (WADA), in addition to previously established target analytes for IRMS in sports drug testing. To date, however, IRMS-based methods validated in accordance with current WADA regulations have not been available. Therefore, the aim of this research project was the development and validation of a method to determine the carbon isotope ratios (CIR) of all newly considered pseudo-endogenous steroids, encompassing the anabolic androgenic steroids comprising a 1-ene-core structure (5α-androst-1-ene-3ß,17ß-diol, 5α-androst-1-ene-3,17-dione [1AD], 17ß-hydroxy-5α-androst-1-en-3-one, 3α-hydroxy-5α-androst-1-ene-17-one [1AND], and 3ß-hydroxy-5α-androst-1-ene-17-one [1EpiAND]), as well as steroids referred to as hormone and metabolic modulators (androsta-1,4,6-triene-3,17-dione [TRD] and its main metabolite 17ß-hydroxy-androsta-1,4,6-triene-3-one) and 6α- and 6ß-hydroxy-androst-4-ene-3,17-dione. With peak purity of target analytes being critical for IRMS analyses, a twofold high-performance liquid chromatography (HPLC)-based sample purification was employed, with all analytes being acetylated between the first and second HPLC fractionation. Using established gas chromatography/combustion/IRMS instrumentation, limits of quantification were estimated at 10 ng/ml for a 20 ml urine aliquot for all analytes, except for 1AND (20 ng/ml), and combined measurement uncertainties were estimated between 0.4‰ and 0.9‰. For proof-of-concept, samples collected after the single oral administration of a nutritional supplement containing 1AD and 1EpiAND were analyzed as well as existing excretion study urine samples obtained after the administration of 4-androstenedione and TRD. Based on the obtained results, the developed method was considered to be fit-for-purpose.

Excretion of oxidated cortisol metabolites is markedly lower than previously assumed: An analysis of urinary cortoic acids in healthy children by GC-MS.

Discovered about 50 years ago, the four C21 steroidal acids (α-)cortolic acid, ß-cortolic acid, (α­)cortolonic acid and ß-cortolonic acid present the oxidative end products of cortisol metabolism. Undergoing renal elimination, these cortoic acids have been assumed to constitute up to 25 % of total urinary cortisol metabolites. However, their analysis has been difficult, only few data has been published in adults, and this class of steroids has become practically forgotten. Since data in children are lacking and nothing is known about their metabolism during human development, we aimed at establishing a more practical analytical method and determined their urinary concentrations in a high number of healthy subjects. In our method, 5-mL-aliquots of 24-hour urine samples were subjected to solid phase extraction (C18 cartridges), followed by strong anion exchange chromatography, and formation of 2-propylester-trimethylsilylether derivatives (2-PR/TMS). The cortoic acids were quantified by targeted gas chromatography-mass spectrometry (GC-MS) using a nonpolar GC column and selected ion monitoring (SIM). Baseline separation of all cortoic acids was achieved. Calibration graphs were linear (R2 > 0.98). Variations in precision and accuracy were less than 15 %, respectively. The detection limit was 100 pg (injected) with a signal-to-noise ratio of 3. 240 specimens from 24-hour urine collections from healthy children (120 boys, 120 girls, aged 3-18 years; DONALD study) were analyzed for cortoic acids and neutral cortisol metabolites to create first reference ranges. The profile of cortoic acids was dominated by α-cortolonic acid with excretion rates up to 70 µg/d. Absolute excretion rates of cortoic acids increased with age, their total excretion rates ranged between 11.0 and 127.3 µg/d (median 45.7 µg/d), but did not show any sexual dimorphism. Since cortoic acids make up only about 1 % of total urinary cortisol metabolites, determination of neutral urinary steroids reliably allows assessment of cortisol production. However, cortoic acids might present potential biomarkers of the body's redox state.

Investigations on the in vivo metabolism of 5α-androst-2-en-17-one.

RATIONALE: The anabolic steroid 5α-androst-2-en-17-one (2EN) is sold as a prohormone and has been investigated regarding its potential as a steroidal aromatase inhibitor. The administration of 2EN was detected in a doping control sample in 2015, and investigations into its metabolism allowed for the identification and characterization of three urinary metabolites. Unfortunately, the utility of the main metabolite 2ß,3α-dihydroxy-5α-androstan-17-one for doping control purposes was hampered under routine doping control conditions due to chromatographic issues, thus warranting further studies on the metabolism of the prohibited substance. METHODS: The metabolism of 2EN was reinvestigated after oral administration of twofold-deuterated 2EN employing hydrogen isotope ratio mass spectrometry (IRMS) in combination with high-accuracy/high-resolution mass spectrometry. After a single dose of 50 mg of doubly labeled 2EN, urine samples were collected for 9 days. All samples were processed using routine doping control methods for IRMS analysis, and all detected metabolites were further characterized by mass spectrometry-based investigations. RESULTS: More than 15 different metabolites still containing the deuterium label were detected after administration. The presence of steroids exhibiting a 5ß-configuration was unexpected as the administered 2EN features a 5α-configured pharmacophore. Further investigations corroborated a significant impact of the administered 2EN on etiocholanolone and 5ß-androstanediol. Seven metabolites of 2EN not present as endogenous compounds were identified as potential candidates for routine doping controls and could be detected for up to 9 days after administration. CONCLUSIONS: The new metabolites identified in this study enable the detection of the misuse of 2EN for up to 9 days. The conversion of a 5α-steroid to urinary metabolites with 5ß-configuration has not been reported so far and should be further investigated.

Validation of steroid ratios for random urine by mass spectrometry to detect 5α-reductase deficiency in Vietnamese children.

OBJECTIVES: The 5α-reductase-type-2 deficiency (5ARD2) is a rare autosomal recessive 46,XY disorder of sex development caused by the mutated 5α-reductase type 2 (SRD5A2) gene. In this disease, defective conversion of testosterone to dihydrotestosterone leads to variable presentations of male ambiguous genitalia during fetal development. We aimed to examine characteristics of patients presenting with 5ARD2 over a 4 year period. METHODS: Random urine samples of control and patients with suspected 5ARD2 were collected and urine steroidomic metabolites were measured by Gas chromatography-mass spectrometry (GC-MS) in the period from 2017 to 2021 at National Children's Hospital, Hanoi Vietnam. 5α- to 5ß-reduced steroid metabolite ratio, 5a-tetrahydrocortisol to tetrahydrocortisol (5α-THF/THF), was reviewed by receive operator characteristics (ROC) curve analysis. Molecular testing was offered to 25 patients who were diagnosed with 5ARD2 by GC-MS urinary steroid analysis. RESULTS: Urine steroidomic profiling was conducted for 104 male controls and 25 patients between the ages of 6 months and 13 years old. Twelve of the twenty-five 5ARD2 patients agreed to undertake genetic analysis, and two mutations of the SRD5A2 gene were detected in each patient, confirming the diagnosis. All patients showed a characteristically low ratio of 5α-THF/THF. There was no overlap of 5α-THF/THF ratio values between control and 5ARD2 groups. The ROC of 5α-THF/THF ratio at 0.19 showed 100% sensitivity and 100% specificity for boys between 6 months and 13 years of age. CONCLUSIONS: Analysis of the urine steroid metabolome by GC-MS can be used to assist in the diagnosis of 5ARD2. We recommend consideration of random urine steroid analysis as a first-line test in the diagnosis of 5ARD2.

Implementation of a marker substance for monitoring in situ 17-keto modifications in endogenous steroids caused by microbiological contamination.

The urinary steroid profile established for the monitoring of eventual testosterone or testosterone precursor application by athletes includes concentrations and ratios of various endogenously produced steroidal hormones and metabolites. Due to enzymatic activities in urine specimens, the concentrations of these endogenous steroids and consequently their ratios may alter, leading to potential misinterpretation of analytical results. Microbiological contamination in athletes' urine samples can occur due to urinary tract infections or due to contamination by the non-sterile sample collection conditions. Depending on the duration of transportation of urine samples, the transport and storage conditions may favour microorganisms' growth, and therefore, the enzymatic activity can be accelerated. Degradation effects on endogenous steroids caused by microorganisms have been observed, such as hydrolysis of steroid conjugates, increase of testosterone in the free fraction or modification of the steroid structure by oxidoreductive reactions. The World Anti-Doping Agency (WADA) implemented criteria to check for signs of microbial degradation in a technical document dealing with the detection, analysis and reporting of endogenous androgenic anabolic steroids (TD EAAS) in urine samples. During the endogenous steroid profile confirmation procedures (CPs) of the WADA accredited Seibersdorf Laboratory, significant differences in the concentrations of markers of the steroid profile were observed compared to the initial testing procedures (ITPs). The changes in concentrations of the urinary steroid profile were attributed to the reduction of the 17-keto group to a 17ß-hydroxy group caused by increased enzymatic activity during the hydrolysis step. In order to monitor the 17-keto reduction activity in athletes' urine specimens, possible marker substances containing a 17-keto group were synthesised and added in the internal standards mixture (ISTD) of the ITP. The presence of the reduced 17ß-hydroxy form of the marker substance indicated enzymatic activity leading to 17-keto reduction reactions. The substance 3ß-ethoxy-5α-androstane-17-one was defined to be suitable to indicate 17-keto reduction reactions occurring during hydrolysis carried out at moderate temperatures.

Non-invasive metabolomics biomarkers of production efficiency and beef carcass quality traits.

The inter-cattle growth variations stem from the interaction of many metabolic processes making animal selection difficult. We hypothesized that growth could be predicted using metabolomics. Urinary biomarkers of cattle feed efficiency were explored using mass spectrometry-based untargeted and targeted metabolomics. Feed intake and weight-gain was measured in steers (n = 75) on forage-based growing rations (stage-1, 84 days) followed by high-concentrate finishing rations (stage-2, 84 days). Urine from days 0, 21, 42, 63, and 83 in each stage were analyzed from steers with the greater (n = 14) and least (n = 14) average-daily-gain (ADG) and comparable dry-matter-intake (DMI; within 0.32 SD of the mean). Steers were slaughtered after stage-2. Adjusted fat-thickness and carcass-yield-grade increased in greater-ADG-cattle selected in stage-1, but carcass traits did not differ between ADG-selected in stage-2. Overall 85 untargeted metabolites segregated greater- and least-ADG animals, with overlap across diets (both stages) and breed type, despite sampling time effects. Total 18-bile acids (BAs) and 5-steroids were quantified and associated with performance and carcass quality across ADG-classification depending on the stage. Stepwise logistic regression of urinary BA and steroids had > 90% accuracy identifying efficient-ADG-steers. Urine metabolomics provides new insight into the physiological mechanisms and potential biomarkers for feed efficiency.

Detection of testosterone microdosing in healthy females.

The ready detectability of synthetic androgens by mass spectrometry (MS)-based antidoping tests has reoriented androgen doping to using testosterone (T), which must be distinguished from its endogenous counterpart making detection of exogenous T harder. We investigated urine and serum steroid and hematological profiling individually and combined to determine the optimal detection model for T administration in women. Twelve healthy females provided six paired blood and urine samples over 2 weeks prior to treatment consisting of 12.5-mg T in a topical transdermal gel applied daily for 7 days. Paired blood and urine samples were then obtained at the end of treatment and Days 1, 2, 4, 7, and 14 days later. Compliance with treatment and sampling was high, and no adverse effects were reported. T treatment significantly increased serum and urine T, serum dihydrotestosterone (DHT), urine 5α-androstane-3α,17ß-diol (5α-diol) epitestosterone (E), and urine T/E ratio with a brief window of detection (2-4 days) as well as total and immature (medium and high fluorescence) reticulocytes that remained elevated over the full 14 posttreatment days. Carbon isotope ratio MS and the OFF score and Abnormal Blood Profile score (ABPS) were not discriminatory. The optimal multivariate model to identify T exposure combined serum T, urine T/E ratio with three hematological variables (% high fluorescence reticulocytes, mean corpuscular hemoglobin, and volume) with the five variables providing 93% correct classification (4% false positive, 10% false negatives). Hence, combining select serum and urine steroid MS variables with reticulocyte measures can achieve a high but imperfect detection of T administration to healthy females.

Longitudinal evaluation of multiple biomarkers for the detection of testosterone gel administration in women with normal menstrual cycle.

In women, hormonal fluctuations related to the menstrual cycle may impose a great source of variability for some biomarkers of testosterone (T) administration, which can ultimately disrupt the sensitivity of their longitudinal monitoring. In this study, the sensitivity of the current urinary and haematological markers of the Athlete Biological Passport (ABP), as well as serum steroid biomarkers, was investigated for the monitoring of a 28-day T gel treatment combined with endogenous fluctuation of the menstrual cycle in 14 healthy female subjects. Additionally, the analysis of urinary target compounds was performed on a subset of samples for endogenous/exogenous origin via isotope ratio mass spectrometry (IRMS). In serum, concentrations of T and dihydrotestosterone (DHT) increased significantly during the treatment, whereas in urine matrix the most affected biomarkers were found to be the ratios of testosterone/epitestosterone (T/E) and 5α-androstane-3α,17ß-diol/epitestosterone (5αAdiol/E). The detection capability of both urinary biomarkers was heavily influenced by [E], which fluctuated depending on the menstrual cycle, and resulted in low sensitivity of the urinary steroidal ABP module. On the contrary, an alternative approach by the longitudinal monitoring of serum T and DHT concentrations with the newly proposed T/androstenedione ratio showed higher sensitivity. The confirmatory IRMS results demonstrated that less than one third of the tested urine samples fulfilled the criteria for positivity. Results from this study demonstrated that the 'blood steroid profile' represents a powerful complementary approach to the 'urinary module' and underlines the importance of gathering bundle of evidence to support the scenario of an endogenous prohibited substance administration.

Nandrolone and estradiol biomarkers identification in bovine urine applying a liquid chromatography high-resolution mass spectrometry metabolomics approach.

With the aim of specifically investigating patterns associated with three steroid treatments (17ß-nandrolone, 17ß-estradiol, and 17ß-nandrolone + 17ß-estradiol) in bovine, an reversed phase liquid chromatography (RPLC)-electrospray ionization (ESI)(+/-)-high-resolution mass spectrometry (HRMS) study was conducted to characterize the urinary profiles of involved animals. Although specific fingerprints with strong differences could be highlighted between urinary metabolite profiles within urine samples collected on control and treated animals, it appeared further that significant discriminations could also be observed between steroid treatments, evidencing thus specific patterns and candidate biomarkers associated to each treatment. An MS-2 structural elucidation step enabled level-1 identification of two biomarkers mainly involved in energy pathways, in relation to skeletal muscle functioning. These results make it possible to envisage a global strategy for the detection of anabolic practices involving steroids, while at the same time providing clues as to the compounds used, which would facilitate the confirmation stage to follow.

Steroid Metabolism in Children and Adolescents With Obesity and Insulin Resistance: Altered SRD5A and 20α/20ßHSD Activity.

Alterations in glucocorticoid metabolism may contribute to the development of obesity and insulin resistance (IR). Obesity in turn affects the androgen balance. The peripheral metabolism of steroids is equally an important determinant of their bioavailability and activity. The aim of this study was to evaluate steroid metabolism in obese children and to define which enzyme alterations are associated with IR. Clinical characteristics and anthropometric measurements were determined in 122 obese children and adolescents (72 girls, 50 boys) aged 8 - 18 years. 26 of them (21.3%) were diagnosed with IR (13 boys, 13 girls). Routine laboratory tests were performed and 24h urinary steroid excretion profiles were analyzed by gas chromatography/mass spectrometry. Positive relationship between 5α-reductase (SRD5A) activity and IR was found. According to the androsterone to etiocholanolone (An/Et) ratio the activity of SRD5A was significantly increased in obese children with IR, but the difference remained insignificant once the 5α-dihydrotestosterone to testosterone (5αDHT/T) ratio was considered. Furthermore, this relationship persisted in boys but was not observed in girls. The activity of 20α-hydroxysteroid dehydrogenase (20αHSD) and 20ß-hydroxysteroid dehydrogenase (20ßHSD) was reduced only in obese girls with IR. Conclude, in the context of obese children and adolescents with IR, we surmise that increased SRD5A represents a compensatory mechanism to reduce local glucocorticoid availability. This phenomenon is probably different in the liver (restriction) and in the adipose tissue (expected increase in activity). We show significant changes in 20αHSD and 20ßHSD activity in obese girls with IR, but it is difficult to clearly determine whether the activity of these enzymes is an indicator of the function in their ovaries or adrenal glands.