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.

Urinary excretion profile of prednisolone and prednisone after rectal administration: Significance in antidoping analysis.

The rectal administration of glucocorticoids, as well as any injectable, and oral ones, is currently prohibited by the World Anti-Doping Agency when occurs "in competition." A reporting level of 100 ng/ml for prednisolone and 300 ng/ml for prednisone was established to discriminate the allowed and the prohibited administration. Here, the urinary excretion profiles of prednisone and prednisolone were evaluated in five volunteers in therapy with glucocorticoid-based rectal formulations containing prednisone or prednisolone caproate.

5α-reductase inhibitors: Evaluation of their potential confounding effect on GC-C-IRMS doping analysis.

5α-reductase inhibitors (5-ARIs) are considered by the World Anti-doping Agency as potential confounding factors in evaluating the athlete steroid profile, since they may interfere with the urinary excretion of several diagnostic compounds. We herein investigated 5α-reductase inhibitors from a different perspective, by verifying their influence on the carbon isotopic composition of 5α- and 5β-reduced testosterone and nandrolone metabolites. The GC-C-IRMS analysis was performed on a set of urine samples collected from three male Caucasian volunteers after the acute and chronic administration of finasteride in combination with the intake of 19-norandrostenedione, a nandrolone precursor.

Detecting the abuse of 19-norsteroids in doping controls: A new gas chromatography coupled to isotope ratio mass spectrometry method for the analysis of 19-norandrosterone and 19-noretiocholanolone.

The detection of 19-norsteroids abuse in doping controls currently relies on the determination of 19-norandrosterone (19-NA) by gas chromatography-tandem mass spectrometry (GC-MS/MS). An additional confirmatory analysis by gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS) is performed on samples showing 19-NA concentrations between 2.5 and 15 ng/ml and not originated from pregnant female athletes or female treated with 19-norethisterone.

Carbon isotopic characterization of prednisolone and prednisone pharmaceutical formulations: Implications in antidoping analysis.

Twenty-two pharmaceutical formulations containing prednisolone or prednisone commercially available in Italy, Belgium, Spain, Brazil, and India were analyzed through a specific gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) method. All of them showed typical non-endogenous δ C values, except for the Belgian nasal spray, Sofrasolone®, with a less depleted C content (-17.84 ± 0.

Development and validation of a method to confirm the exogenous origin of prednisone and prednisolone by GC-C-IRMS.

Prednisone and prednisolone are two anti-inflammatory steroidal drugs listed by the World Anti-Doping Agency (WADA) within the class of glucocorticoids, which are prohibited "in competition" and when administered systemically. Their presence in collected urine samples may be attributed, if no exogenous administration has occurred, to an in situ microbial formation from endogenous steroids. In this work, a gas chromatography coupled to carbon isotope ratio mass spectrometry (GC-C-IRMS) method was developed and validated to distinguish an exogenous origin from an endogenous one.