Fluoxymesterone (9α-fluoro-11β,17β-dihydroxy-17α-methyl-androst-4-en-3-one) is a prohibited anabolic androgenic steroid (AAS) under the regulations of the World Anti-Doping Agency (WADA). Comprehensive elucidation of its metabolic pathways and the identification of novel metabolites are essential for improving doping control. In this study, two healthy male volunteers were orally administered a single 10 mg dose of fluoxymesterone, and urine samples were systematically collected over a 30-day period. An optimized three-step pretreatment procedure combined with gas chromatography-Orbitrap high-resolution mass spectrometry (GC-Orbitrap-HRMS) enabled the comprehensive detection of free, glucuronide-conjugated, and sulfate-conjugated metabolites. In total, the parent compound and ten metabolites were identified, including five novel structures reported for the first time. The primary metabolic transformations involved 4-ene reduction, 3-keto reduction, 6β-hydroxylation, 11β-hydroxy oxidation, and skeletal rearrangement. Excretion profiling demonstrated substantial interindividual variability in metabolite concentrations and clearance kinetics. Notably, the newly identified metabolite F-M7 (9α-fluoro-17α-methyl-3ξ,11β,17β-triol-5ξ-androstane) was detectable as a glucuronide conjugate for up to 5 days post-administration, highlighting its potential as a reliable biomarker. These findings expand the understanding of fluoxymesterone metabolism in vivo and propose promising analytical targets for enhancing the sensitivity and reliability of anti-doping strategies.

Steroid hormones (SHs) have posed a serious threat to ecosystems and human health. The development of rapid assays for the detection of different SHs is urgent for the ecological and human health. However, the rapid detection of SHs residues in the environment is still a challenge due to the wide variety of SHs and their poor electroactivity. Herein, we introduced a novel nonbiological sensing system utilizing sulfobutyl β-cyclodextrin as a recognition unit for the simultaneous and sensitive detection of multiple SHs in water. The mechanism study showed that the sulphonate group in the prepared SBE-β-CD@CdTe/P(L-Arg)/GCE has a high affinity for the Δ[4]-3-ketone group in SHs, while the hydrophobic cavity could interact with the unsaturated bond of the C-17 side chain of SHs, resulting in a dual recognition system. Further, the analytical performance of this method was evaluated using 30 different substances, including 24 SHs and 6 steroidal analogues. The results showed that this sensor could simultaneously detect a wide range of SHs containing the Δ[4]-3-ketone group. The sensor was then applied to simultaneously monitor dexamethasone, fluoxymesterone, and chlormadinon in environmental water samples, and the results were satisfactory with detection limits of 4.1 nmol L[-1], 3.4 nmol L[-1], and 7.7 nmol L[-1], respectively. Meanwhile, the SBE-β-CD@CdTe/P(L-Arg) sensing system exhibited a strong specificity for the target substances. Thus, this sensing system enables the rapidly identifying multiple SHs in the aquatic environment and has great potential applications in environmental studies, illicit addition and drug analysis. In addition, this study provides a new idea and theoretical basis for the construction of on-line monitoring method for strong physiologically active components.

MYRF-related cardiac urogenital syndrome (MYRF-CUGS) is primarily characterized by anomalies of the internal and external genitalia, congenital heart defects, and eye anomalies. 46,XY individuals can have a range of anomalies of the genitalia, from isolated unilateral cryptorchidism to ambiguous genitalia to typical-appearing female genitalia. 46,XX individuals can have atypical internal genitalia including absent uterus, absent fallopian tubes, small or absent ovaries, absent vagina, or blind-ending vagina. A number of congenital heart defects have been described, with scimitar syndrome being the most common. Eye issues, present in a vast majority of affected individuals, include high hyperopia and nanophthalmos (an ocular malformation featuring short axial length due to small anterior and posterior segments with thickened choroid and sclera and normal lens volume). Because of the common nature of the eye anomalies, it has been suggested that this condition may be more accurately referred to as "MYRF-related ocular cardiac urogenital syndrome." Other features of the condition include a broad range of developmental delay /intellectual disability (DD/ID), from typical development and cognition to severe DD/ID; pulmonary abnormalities and diaphragmatic issues (congenital diaphragmatic hernia / diaphragmatic eventration); intestinal malrotation; and mild growth and feeding problems.

Nonsyndromic 46,XX testicular disorders/differences of sex development (DSD) are characterized by: the presence of a 46,XX karyotype; external genitalia ranging from typical male to ambiguous; two testicles; azoospermia; absence of müllerian structures; and absence of other syndromic features, such as congenital anomalies outside of the genitourinary system, learning disorders / cognitive impairment, or behavioral issues. Approximately 85% of individuals with nonsyndromic 46,XX testicular DSD present after puberty with normal pubic hair and normal penile size but small testes, gynecomastia, and sterility resulting from azoospermia. Approximately 15% of individuals with nonsyndromic 46,XX testicular DSD present at birth with ambiguous genitalia. Gender role and gender identity are reported as male. If untreated, males with 46,XX testicular DSD experience the consequences of testosterone deficiency.

Several studies have highlighted that nutritional supplements may contain undeclared anabolic steroids that are banned by the International Olympic Committee/World Anti-Doping Agency. Any kind of abuse with these drugs is extremely dangerous because of their side effects. Thus, the control of food additives in order to protect the best consumer health and to limit fraudulent practices in the field of sports is essential. This paper describes a simple and effective qualitative gas chromatography-mass spectrometry (GC-MS) method to detect anabolic androgenic steroids (AAS): androsterone, nandrolene, dehydroepiandrosterone, 5ɑ-androstane-3β, 17β-diol, dihydrotestosterone, testosterone, methenolone acetate, methandienone, boldenone and fluoxymesterone, in food supplements. Methyltestosterone was used as internal standard. Target compounds were extracted with a mixture of N-pentane and di-ethylether (7.5:2.5, v/v). A good extraction recovery was obtained by our method for all the AAS (R > 88%). Crude extract was derivatized with N-methyl-N-trimethylsilyl-trifluoracetamide. Separation was performed on a GC connected to quadrupole MS detector using a 5% phenylmethylsiloxane fused silica capillary column (30 m × 0.25 mm i.d.; film thickness, 0.25 µm). Helium was used as carrier gas with a flow rate of 0.3 µl min-1 (measured at 6.1 psi 190 °C). The MS was operated in electron ionization mode (70 eV) and in selected ion monitoring (SIM). The mass spectra of the standard compounds were acquired in full SCAN mode (50-700 m/z) by infusion of a reference solution at 50 µg/ml. Three higher diagnostic ions were monitored for each compound of interest. All AAS get separated with good peak shapes and resolution factor. The total analysis time by our optimised method was only 20 min. The developed method was validated according to Laboratories International Standard regulations for specificity, precision in both liquid and solid matrixes, and memory effect. The Tolerance Interval was judged true. The limit of detection was about 10 ng/g for solid samples and 10 ng/ml for liquid samples. The developed method was then applied to the research of steroids in nine Tunisian commercially dietary supplements using for each compound of interest SIM mode for screening then SCAN mode for confirmation. One of the monitoring samples was positive to methandienone not declared on the label. Our analytical method can be beneficial for AAS screening in dietary supplements.

Nonpolar anabolic steroids are doping agents that typically do not provide strong signals by electrospray ionization-mass spectrometry (ESI-MS) owing especially to the low polarity of the functional groups present. We have investigated the addition of anions, in ammonium salt form, to anabolic steroid samples as ionization enhancers and have confirmed that lower instrumental limits of detection (as low as 10 ng/mL for fluoxymesterone-M) are obtained by fluoride anion attachment mass spectrometry, as compared to ESI(+)/(-) or atmospheric pressure photoionization (APPI)(+). Moreover, collision-induced decomposition (CID) spectra of precursor fluoride adducts of the bifunctional steroid "reduced pregnenolone" (containing two hydroxyl groups) and its d4-analogue provide evidence of regiospecific decompositions after attachment of fluoride anion to a specific hydroxyl group of the steroid. This type of charting of specific CID reaction pathways can offer value to selected reaction monitoring experiments (SRM) as it may result in a gain in selectivity in detection as well as in improvements in quantification.

Gynaecomastia is a benign condition characterised by enlargement of the male breast. Drug-induced gynaecomastia merits deep consideration as it may account for as many as 25% of all cases of gynaecomastia in adults. Although the mechanism is not fully clear, some mechanisms include oestrogen-like activities, stimulation of testicular production of oestrogens, inhibition of testosterone synthesis or blockade of androgen action. Anabolic steroids, in particular when used during the pubertal stage, may cause significant irreversible gynaecomastia. We report a case of 28-year-old Filipino man with persistent gynaecomastia from fluoxymesterone used for aplastic anaemia during his prepubertal stage. Hormonal work ups for gynaecomastia all turned out normal, thus isolating the drug as the cause. The patient was unable to undergo breast reconstruction surgery due to haematological contraindications, but eventually referred to psychiatry for counselling. This case will highlight the paradoxical effect of androgenic steroid used during childhood on male breast proliferation during puberty.

A method was developed for the determination of 11 anabolic hormones (boldenone, androstenedione, nandrolone, methandrostenolone, methyltestosterone, testosterone, testosterone acetate, trenbolone, testosterone propionate, stanozolol, fluoxymesterone) in fish by multi-function impurity adsorption solid-phase extraction-ultrafast liquid chromatography-tandem mass spectrometry. After the sample was extracted by methanol, the extract was cleaned-up quickly by C18 adsorbent, neutral alumina adsorbent and amino-functionalized nano-adsorbent. The separation was performed on a Shim-Pack XR-ODS II column (100 mm x 2.0 mm, 2.2 microm) using the mobile phases of 0.1% (v/v) formic acid in acetonitrile and 0.1% (v/v) formic acid solution in a gradient elution mode. The identification and quantification were achieved by using electrospray ionization in positive ion mode (ESI+) in multiple reaction monitoring (MRM) mode. The matrix-matched external standard calibration curves were used for quantitative determination. The results showed that the calibration curves were in good linearity for the eleven analytes with the correlation coefficients (r) more than 0.999. The limits of detection (LODs, S/N > 3) for the 11 anabolic hormones were from 0.03 microg/kg to 0.4 microg/kg and the limits of quantification (LOQs, S/N > 10) were from 0.1 microg/kg to 1.5 microg/kg. The average recoveries ranged from 80.9% to 98.1% with the relative standard deviations between 5.2% and 11.5%. The method is simple, rapid, sensitive, accurate and suitable for the quantitative determination and confirmation of the 11 anabolic hormones in fish.

In this study fluoxymesterone urinary profiles were investigated by liquid chromatography quadrupole time-of-flight tandem mass spectrometry (LC-QTOFMS) with accurate mass measurement. Twelve metabolites including the parent drug were detected in two fluoxymesterone positive control urine samples. Three parameters were employed for evaluation of the accuracy of the chemical formulae in positive full scan experiment, which contained error between actual and calculated mass weights of prontonated and isotopic molecules together with abundance match between prontonated and isotopic molecules. The 13 analytes were determined with mass accuracy less than 1.1 ppm and isotopic abundance match more than 94 marks. Based on the ionization, CID fragmentation, the accurate mass of the product ion and comparison of the accurate mass weight and retention time with reference standard, fluoxymesterone and its 12 metabolites containing three unreported ones were detected. The chemical structures of three unreported metabolites were identified as: 9-fluro-17β-ol-17-methyl-11-en-5α-androstan-3-one (F13), 9-fluro-17β-ol-17-methyl-11-en-5β-androstan-3-one (F8) and 9-fluro-17β-ol-17-methyl-5-androstan-3,6,11-trione, and meanwhile a dihydroxylated metabolite (F12), 6,16-dihydroxylated fluoxymesterone, was also detected in human urine, which was previously reported to be available only in equine urine.

Anabolic androgenic steroids (AAS) are testosterone derivatives used either clinically, in elite sports, or for body shaping with the goal to increase muscle size and strength. Clinically developed compounds and nonclinically tested designer steroids often marketed as food supplements are widely used. Despite the considerable evidence for various adverse effects of AAS use, the underlying molecular mechanisms are insufficiently understood. Here, we investigated whether some AAS, as a result of a lack of target selectivity, might inhibit 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2)-dependent inactivation of glucocorticoids. Using recombinant human 11β-HSD2, we observed inhibitory effects for several AAS. Whereas oxymetholone, oxymesterone, danazol, and testosterone showed medium inhibitory potential, fluoxymesterone was a potent inhibitor of human 11β-HSD2 (half-maximal inhibitory concentration [IC(50)] of 60-100nM in cell lysates; IC(50) of 160nM in intact SW-620, and 530nM in MCF-7 cells). Measurements with rat kidney microsomes and lysates of cells expressing recombinant mouse 11β-HSD2 revealed much weaker inhibition by the AAS tested, indicating that the adverse effects of AAS-dependent 11β-HSD2 inhibition cannot be investigated in rats and mice. Furthermore, we provide evidence that fluoxymesterone is metabolized to 11-oxofluoxymesterone by human 11β-HSD2. Structural modeling revealed similar binding modes for fluoxymesterone and cortisol, supporting a competitive mode of inhibition of 11β-HSD2-dependent cortisol oxidation by this AAS. No direct modulation of mineralocorticoid receptor (MR) function was observed. Thus, 11β-HSD2 inhibition by fluoxymesterone may cause cortisol-induced MR activation, thereby leading to electrolyte disturbances and contributing to the development of hypertension and cardiovascular disease.

This study was designed to examine the interaction of two anti-breast cancer drugs, i.e., fluoxymesterone (FLU) and cyclophosphamide (CYC), with human serum albumin (HSA) using different kinds of spectroscopic, zeta potential and molecular modeling techniques under imitated physiological conditions. The RLS technique was utilized to investigate the effect of the two anticancer drugs on changes of the protein conformation, both separately and simultaneously. Our study suggested that the enhancement in RLS intensity was attributed to the formation of a new complex between the two drugs and the protein. Both drugs demonstrated a powerful ability to quench the fluorescence of HSA, and the fluorescence quenching action was much stronger when the two drugs coexisted. The quenching mechanism was suggested to be static as confirmed by time-resolved fluorescence spectroscopy results. The effect of both drugs on the conformation of HSA was analyzed using synchronous fluorescence spectroscopy. Our results revealed that the fluorescence quenching of HSA originated from the Trp and Tyr residues, and demonstrated a conformational change of HSA with the addition of both drugs. The binding distances between HSA and the drugs were estimated by the Förster theory, and it was revealed that nonradiative energy transfer from HSA to both drugs occurred with a high probability. According to CD measurements, the influence of both drugs on the secondary structure of HSA in aqueous solutions was also investigated and illustrated that the α-helix content of HSA decreased with increasing drug concentration in both systems. Moreover, the zeta-potential experiments revealed that both drugs induced conformational changes on HSA. Docking studies were also performed and demonstrated that a reduction of the binding affinity between the drugs and HSA occurred in the presence of both drugs.