Elimination profiles of prednisone and prednisolone after different administration routes: Evaluation of the reporting level and washout periods to ensure safe therapeutic administrations.

Prednisolone (PRED) and prednisone (PSONE) are prohibited in sports competitions when administered by systemic routes, and they are allowed by other routes for therapeutic purposes. There is no restriction of use in out-of-competition periods. The present study aimed to evaluate the urinary excretion of PRED, PSONE, and their most important metabolites after systemic and nonsystemic treatments in order to verify the suitability of the current reporting level of 30 ng/ml used to distinguish allowed and prohibited administrations and to establish washout periods for oral treatments performed in out-of-competition periods. PRED was studied after dermatological administration (5 mg/day for 5 days, n = 6 males) and oral administration (5 mg, n = 6 males; 10 mg, n = 2 males). PSONE was studied after oral administration (10 mg, n = 2 males; 30 mg, n = 1 male and 1 female). Concentrations in urine were measured using an LC-MS/MS method. Concentrations after dermatological treatment were low for all metabolites. After oral administration, concentrations were very high during the first 24 h after administration ranging from 1.6 to 2261 ng/ml and from 4.6 to 908 ng/ml for PRED and PSONE, respectively. Concentrations of most of the metabolites measured were lower than 30 ng/ml from 24 h after all oral administrations. New reporting levels are proposed for PRED and PSONE considering data of our study and other information published after nonsystemic administrations of the compounds. Washout periods of at least 24 h are recommended to ensure no false positives when oral treatments need to be performed in out-of-competition periods.

Elimination profiles of betamethasone after different administration routes: Evaluation of the reporting level and washout periods to ensure safe therapeutic administrations.

Betamethasone (BET) is prohibited in sports competitions when administered by systemic routes, and it is allowed by other routes for therapeutic purposes. In out-of-competition periods, there is no restriction of use. The present work aimed to assess the urinary excretion of BET and its metabolites after allowed and prohibited administrations to verify the suitability of the current reporting level of 30 ng/ml used to distinguish allowed and prohibited administrations and to establish washout periods for oral and intramuscular (IM) administrations when out-of-competition treatments are needed. BET was administered to healthy volunteers by different routes: topical (10 mg/day for 5 days, n = 6 males), intranasal (320 µg/day for 3 days, n = 4 males and 4 females), oral (0.5 mg, n = 8 males) or IM (6 mg, n = 6 males, or 12 mg, n = 4 males and 4 females). Urine and plasma samples collected before and after administration were analysed using liquid chromatography-tandem mass spectrometry. Among all studied metabolites, the parent drug was selected as the best discriminatory marker. After topical administration, BET concentrations were lower than 6.6 ng/ml. However, after intranasal treatment, some samples at concentrations close to or higher than 30 ng/ml were detected, suggesting the need to revise the current reporting level. Urinary concentrations after oral and intranasal administrations were similar, and after IM administration, concentrations were much higher. Taking into account all information, a urinary reporting level of 60 ng/ml is proposed. Washout periods of at least 48 and 96 h are recommended after oral and IM administrations, respectively.

Budesonide use and misuse in sports: Elimination profiles of budesonide and metabolites after intranasal, high-dose inhaled and oral administrations.

Budesonide (BUD) is a glucocorticoid (GC) widely used in therapeutics. In sports, the World Anti-doping Agency (WADA) controls the use of GCs, and WADA-accredited laboratories use a reporting level of 30 ng/mL for 6ß-hydroxy-budesonide (6ßOHBUD) to detect the systemic administration of BUD. In the present work, we examined the urinary excretion profile of 6ßOHBUD, BUD, and 16α-hydroxy-prednisolone (16αOHPRED) after intranasal (INT), inhaled (INH) (at high doses) and oral administrations in male and female volunteers. BUD was administered to healthy volunteers using INT route (256 µg/day for three days, n = 4 males and 4 females), INH route (800 µg/day for three days, n = 4 males and 4 females, and 1600 µg/day for three days, n = 4 males) or oral route (3 mg, n = 8 females). Urine samples were collected before and after administration at different time periods, and were analyzed by liquid chromatography-tandem mass spectrometry. 6ßOHBUD and BUD concentrations were very low after INT treatment (0.0-7.1 and 0.0-8.1 ng/mL, respectively), and higher after INH treatments (0.0-35.4 and 0.0-48.3 ng/mL, respectively). For 16αOHPRED, elevated concentrations were detected after INT and INH treatments (2.6-66.4 and 3.4-426.5 ng/mL, respectively). Concentrations obtained following oral administration were higher than after therapeutic administrations (2.8-80.6, 1.5-36.1, and 10.4-532.2 ng/mL for 6ßOHBUD, BUD, and 16αOHPRED, respectively). After all administrations, concentrations were higher in males than in females. Results demonstrated that 6ßOHBUD is the best discriminatory marker and a reporting level of 40 ng/mL was found to be the best criterion to distinguish allowed from forbidden administrations of BUD.

Additional studies on triamcinolone acetonide use and misuse in sports: Elimination profile after intranasal and high-dose intramuscular administrations.

Triamcinolone acetonide (TA) is a glucocorticoid (GC) widely used in sports medicine. GCs are prohibited in sports competitions by oral, intramuscular (IM), intravenous and rectal administrations, and they are allowed by other routes considered of local action such as intranasal administration (INT). We examined the urinary profiles of TA and its metabolites after INT and high-dose IM administrations. We also measured concentrations of TA and cortisol (CORT) in plasma following IM administration. TA was administered to healthy volunteers using INT route (220 µg/day for 3 days, n = 4 males and 4 females) or IM route (single dose of 40 mg, n = 4 males and 4 females and single dose 80 mg, n = 4 males). Urine and plasma samples were collected before and after administration at different time periods, and were analysed by liquid chromatography-tandem mass spectrometry. TA concentrations in urine were constant during 23 days after IM injection (range 1.4-129.0 ng/mL), and were very low after INT administration (range 0.0-3.5 ng/mL). For 6ß-hydroxy-triamcinolone, the main TA metabolite, higher concentrations were detected (0.0-93.7 ng/mL and 15.7-973.9 ng/mL after INT and IM administrations, respectively). On the other hand, TA was detected in all plasma samples collected during 23 days after IM administration (range 0.2-5.7 ng/mL). CORT levels were largely suppressed after IM injection, and were recovered in a dose-dependent manner. In view of the results obtained, we propose a reporting level of 5 ng/mL for TA to distinguish forbidden from allowed TA administrations in sports. We also suggest that other GCs with faster urinary elimination from the body should be considered for IM therapies in out-of-competition rather than TA, in order to reduce the possibility of reporting false adverse analytical findings.

Elimination profile of triamcinolone hexacetonide and its metabolites in human urine and plasma after a single intra-articular administration.

Triamcinolone hexacetonide (THA) is a synthetic glucocorticoid (GC) used by intra-articular (IA) administration. GCs are prohibited in sports competitions by systemic routes, and they are allowed by other routes considered of local action (IA administration, among others). The aim of the present work was to study the metabolic profile of THA in urine and plasma following IA administration. Eight patients (4 males and 4 females) with knee osteoarthritis received an IA dose of THA (40 mg) in the knee joint. Spot urine and plasma samples were collected before injection and at different time periods up to day 23 and 10 post-administration, respectively. The samples were analysed by liquid chromatography-tandem mass spectrometry. Neither THA nor specific THA metabolites were detected in urine. Triamcinolone acetonide (TA) and 6ß-hydroxy-triamcinolone acetonide were the main urinary metabolites. Maximum concentrations wereobtained between 24 and 48 h after administration. Using the reporting level of 30 ng/mL to distinguish allowed from forbidden administrations of GCs, a large number of false adverse analytical findings would be reported up to day 4. On the other hand, TA was detected in all plasma samples collected up to day 10 after administration. THA was also detected in plasma but at lower concentrations. The detection of plasma THA would be an unequivocal proof to demonstrate IA use of THA. A reversible decrease was observed in plasma concentrations of cortisol in some of the patients, indicating a systemic effect of the drug.

The effect of tea consumption on the steroid profile.

Green tea (GT), along with its flavonol epigallocatechin-3-gallate (EGCG), has shown to inhibit the UGT2B17 isoenzyme, which is highly involved in the glucuronidation of testosterone (T) and its metabolites. Since the steroid profile (SP) is composed of urinary concentrations of T and related metabolites excreted in both the free and the glucuronide fractions, GT consumption could alter the SP, leading to misunderstanding in doping controls. The aim of the present work was to study the effect of GT consumption on the SP. This study was performed with 29 male volunteers, which could be classified in 2 arms depending on their T/E values (0.12 ± 0.02, n = 12; 1.64 ± 0.90, n = 17). The clinical protocol was designed to evaluate the effect of GT administration on the SP biomarkers. Participants were asked to consume GT with a high content of EGCG for 7 days (5 GT beverages along the whole day for days 1-6 and 9 GT beverages on day 7, corresponding to 520 and 936 mg/day of EGCG, respectively). Urine samples were collected before and during GT consumption at different time periods. The SP was measured using gas chromatography-mass spectrometry. The excretion rates of the SP metabolites did not change after GT consumption. Moreover, the individual evaluation of the subject's steroidal biological passport resulted in normal sequences. The results obtained show that GT consumption does not distort the establishment of normal ranges of SP parameters. Therefore, GT consumption does not need to be considered a confounding factor in the SP evaluation.

Effect of glucocorticoid administration on the steroid profile.

The steroid profile (SP) is a powerful tool to detect the misuse of endogenous anabolic androgenic steroids in sports, and it is included in the Athlete Biological Passport (ABP). Glucocorticoids (GCs), which are widely prescribed in sports and only prohibited in competition by systemic routes, inhibit the hypothalamic-pituitary-adrenal axis. Since the metabolites monitored in the SP have a partial adrenal origin, their excretion in urine might be altered by GCs consumption. The aim of the present work was to investigate if GCs administered by either systemic or local routes could influence the SP parameters. Three of the most frequently detected GCs in sports (prednisolone, betamethasone, and triamcinolone acetonide) were administered to healthy male and female volunteers (n=40) using different administration routes (topical, oral, and intramuscular administration at different doses). In total, 66 administrations of GCs were performed. Urine samples were collected before and after GCs administration. The SP was measured using gas chromatography-mass spectrometry. The excretion rates of the SP metabolites decreased after systemic GCs administration. This excretion decrease showed to be associated with the dose and the administration route. However, the individual evaluation of the SP ratios (T/E, A/T, A/Etio, 5αAdiol/5ßAdiol, and 5αAdiol/E) led to normal sequences for all the conditions tested. Therefore, GCs administration did not produce misinterpretations on the ABP evaluation. According to these results, GCs administration should not distort the establishment of normal ranges of the SP ratios, and does not need to be considered a confounding factor in the SP evaluation.

Ionization and collision induced dissociation of steroid bisglucuronides.

Studies on steroid metabolism are of utmost importance to improve the detection capabilities of anabolic androgenic steroids (AASs) misuse in sports drug testing. In humans, glucuronoconjugates are the most abundant phase II metabolites of AAS. Bisglucuronidation is a reaction where two separated functional groups on the same molecule are conjugated with glucuronic acid. These metabolites have not been studied in depth for steroids and could be interesting markers for doping control. The aim of the present work was to study the ionization and collision-induced dissociation of steroid bisglucuronides to be able to develop mass spectrometric analytical strategies for their detection in urine samples after AAS administration. Because steroid bisglucuronides are not commercially available, 19 of them were qualitatively synthesized to study their mass spectrometric behavior. Bisglucuronides ionized as [M+NH4 ]+ in positive mode, and as [M-H]- and [M-2H]2- in negative mode. The most specific product ions of steroid bisglucuronides in positive mode resulted from the neutral losses of 387 and 405 Da (corresponding to [M+NH4 -NH3 -2gluc-H2 O]+ and [M+NH4 -NH3 -2gluc-2H2 O]+ , respectively, being "gluc" a dehydrated glucuronide moiety), and in negative mode, the fragmentation of [M-2H]2- showed ion losses of m/z 175 and 75 (gluc- and HOCH2 CO2- , respectively). On the basis of the common behavior, a selected reaction monitoring method was developed to detect bisglucuronide metabolites in urine samples. As a proof of concept, urines obtained after administration of norandrostenediol were studied, and a bisglucuronide metabolite was detected in those urines. The results demonstrate the usefulness of the analytical strategy to detect bisglucuronide metabolites in urine samples, and the formation of these metabolites after administration of AAS.

Detection of stanozolol O- and N-sulfate metabolites and their evaluation as additional markers in doping control.

Stanozolol (STAN) is one of the most frequently detected anabolic androgenic steroids in sports drug testing. STAN misuse is commonly detected by monitoring metabolites excreted conjugated with glucuronic acid after enzymatic hydrolysis or using direct detection by liquid chromatography-tandem mass spectrometry (LC-MS/MS). It is well known that some of the previously described metabolites are the result of the formation of sulfate conjugates in C17, which are converted to their 17-epimers in urine. Therefore, sulfation is an important phase II metabolic pathway of STAN that has not been comprehensively studied. The aim of this work was to evaluate the sulfate fraction of STAN metabolism by LC-MS/MS to establish potential long-term metabolites valuable for doping control purposes. STAN was administered to six healthy male volunteers involving oral or intramuscular administration and urine samples were collected up to 31 days after administration. Sulfation of the phase I metabolites commercially available as standards was performed in order to obtain MS data useful to develop analytical strategies (neutral loss scan, precursor ion scan and selected reaction monitoring acquisitions modes) to detect potential sulfate metabolites. Eleven sulfate metabolites (M-I to M-XI) were detected and characterized by LC-MS/MS. This paper provides valuable data on the ionization and fragmentation of O-sulfates and N-sulfates. For STAN, results showed that sulfates do not improve the retrospectivity of the detection compared to the previously described long-term metabolite (epistanozolol-N-glucuronide). However, sulfate metabolites could be additional markers for the detection of STAN misuse. Copyright © 2016 John Wiley & Sons, Ltd.

Detection and characterization of clostebol sulfate metabolites in Caucasian population.

Anabolic androgenic steroids (AAS) are synthetic testosterone derivatives which undergo extensive metabolism in man. Differences in the excretion of phase II metabolites are strongly associated with inter-individual and inter-ethnic variations. Sulfate metabolites have been described as long-term metabolites for some AAS. Clostebol is the 4-chloro derivative of testosterone and the aim of the present study was the evaluation of clostebol sulfate metabolites in Caucasian population by LC-MS/MS technology. Clostebol was orally administered to four healthy Caucasian male volunteers, and excretion study urines were collected up to 31 days. Several analytical strategies (neutral loss scan, precursor ion scan and selected reaction monitoring acquisitions modes) were applied to detect sulfate metabolites in post-administration samples. Sixteen sulfate metabolites were detected, five of them having detectability times above 10 days (S1a, S2a, S3b, S3g and S4b). Interestingly, metabolite S1a could be detected up to the last collected sample of all excretion studies and it was characterized by LC-MS/MS and GC-MS as 4ξ-chloro-5α-androst-3ß-ol-17-one 3ß-sulfate. Thus, monitoring of S1a improves the detection time of clostebol misuse with respect to the commonly monitored metabolites, excreted in the glucuronide fraction. Importantly, this new metabolite can be incorporated into recently developed LC-MS/MS screening methods base on the direct detection of phase II metabolites.

Bioanalytical techniques in discrimination between therapeutic and abusive use of drugs in sport.

The discrimination between therapeutic and abusive use of drugs in sports is performed using threshold concentrations or reporting levels, and the detection of the substances in a sample is only reported as an adverse analytical finding when the concentration exceeds the threshold or the reporting level. In this paper, the strategies of discrimination and the analytical methods used for the main groups of substances where the distinction is needed (ß-2 agonists, ephedrines, glucocorticoids and morphine) will be reviewed. Nowadays, LC-MS is the method of choice for the analysis of these substances and, in most of the cases, a simple dilution of the urine sample is performed before the chromatographic analysis.

Detection and characterization of prednisolone metabolites in human urine by LC-MS/MS.

Glucocorticosteroids are prohibited in sports when used by systemic administrations (e.g. oral), whereas they are allowed using other administration ways. Strategies to discriminate between administrations routes have to be developed by doping control laboratories. For this reason, the metabolism of prednisolone (PRED) was studied using liquid chromatography coupled to tandem mass spectrometry. A single oral (10 mg) dose of PRED was administered to two healthy male volunteers. Urine samples were collected up to 6 days after administration. Samples were hydrolyzed with ß-glucuronidase and subjected to liquid-liquid extraction with ethyl acetate in alkaline conditions. The extracts were analyzed by liquid chromatography coupled to tandem mass spectrometry. Precursor ion scan methods (m/z 77, 91, 105, 121, 147 and 171) in positive ionization and neutral loss scan methods (76 and 94 Da) in negative ionization modes were applied for the open detection of PRED metabolites. Using these methods, PRED parent compound plus 20 metabolites were detected. PRED and 11 metabolites were characterized by comparison with standards of the compounds (PRED, prednisone, 20ß-dihydro-PRED and 20α-dihydro-PRED, 20ß-dihydro-prednisone and 20α-dihydro-prednisone, 6ß-hydroxy-PRED and 6α-hydroxy-PRED, 20ß isomers and 20α isomers of 6ß,11ß,17α,20,21-pentahydroxypregnan-1,4-diene-3-one, 6α,11ß,17α,20ß,21-pentahydroxypregnan-1,4-diene-3-one and Δ(6) -PRED). Using mass spectrometric data, feasible structures were proposed for seven of the remaining nine detected metabolites, including several 6-hydroxy-metabolites. Eleven of the characterized metabolites have not been previously described. Maximum excretion rates for PRED metabolites were achieved in first 24 h; however, most of the metabolites were still detectable in the last collected samples (day 6).

Detection and characterization of betamethasone metabolites in human urine by LC-MS/MS.

Glucocorticosteroids are prohibited in sports when administered by systemic routes and allowed using other administrations for therapeutic reasons. Therefore, markers to distinguish between routes of administration through the analysis of urine samples are needed in anti-doping control. As a first step to achieve that goal, the metabolism of betamethasone (BET) was investigated in the present work. Urine samples obtained after BET intramuscular injection were hydrolyzed with ß-glucuronidase and subjected to liquid-liquid extraction with ethyl acetate in alkaline conditions. The extracts were analyzed by liquid chromatography coupled to tandem mass spectrometry. Common open screening methods for fluorine containing corticosteroids (precursor ion scan method of m/z 121, 147, 171, and neutral loss (NL) scan methods of 20 and 38 Da in positive ionization, and 46 and 76 Da in negative ionization) were applied to detect BET metabolites. Moreover, an NL method was applied to detect A-ring reduced metabolites of BET, which are ionized as [M+NH4 ](+) (NL of 55, 73, and 91 Da, corresponding to the consecutive losses of NH3 , HF and one, two and three water molecules, respectively). BET and 24 metabolites were detected. Six metabolites were identified by comparison with standards, and for ten, feasible structures were proposed based on mass spectrometric data. Eleven of the characterized metabolites had not been previously reported. Metabolites resulting from 11-oxidation, 6-hydroxylation, C20 or 4-ene-3-one reduction and combination of some of them were detected. Moreover one metabolite resulting from cleavage of the side chain with subsequent oxidation of carbon at C17 was also detected.

Evaluation of the reporting level to detect triamcinolone acetonide misuse in sports.

Triamcinolone acetonide (TA) is prohibited in sport competitions using systemic administrations (e.g., intramuscular, IM), and it is allowed by other routes (e.g., intranasal, IN, or topical, TOP). A reporting level of 30 ng/mL is used to discriminate between forbidden and allowed administrations. We examined urinary profiles of TA metabolites after TOP, IN and IM administrations to evaluate the suitability of the current reporting level and to define the best criteria to discriminate between these administrations. TA was administered to healthy volunteers by different routes: a single IM dose (n=2), IN doses for three days (n=6), and TOP doses for five days followed by a single IM dose (n=8). Urine samples were collected at different time intervals and they were analyzed by liquid chromatography-tandem mass spectrometry to measure TA and eight metabolites. After TOP and IN administrations, concentrations of the metabolites were significantly lower (p<0.05) than after IM administrations. Concentrations of TA after IM administration were lower than 30 ng/mL for all volunteers (range 0.7-29.7 ng/mL), and they were lower than 5 ng/mL after multiple IN or TOP doses (0.1-3.6 ng/mL and 0-1.7 ng/mL, respectively). For 6ß-hydroxy-TA, the main TA metabolite, greater concentrations were obtained: 10.7-469.1 ng/mL, 2.2-90.6 ng/mL and 0-57.2 ng/mL after IM, IN and TOP administrations, respectively. These results suggest that the current reporting level is not suitable to detect forbidden IM administration of TA. A lower concentration of the parent drug or the use of specific metabolites could discriminate IM from TOP or IN administrations.

Biochemical and Physiological Improvement in a Mouse Model of Smith-Lemli-Opitz Syndrome (SLOS) Following Gene Transfer with AAV Vectors.

Smith-Lemli-Opitz syndrome (SLOS) is an inborn error of cholesterol synthesis resulting from a defect in 7-dehydrocholesterol reductase (DHCR7), the enzyme that produces cholesterol from its immediate precursor 7-dehydrocholesterol. Current therapy employing dietary cholesterol is inadequate. As SLOS is caused by a defect in a single gene, restoring enzyme functionality through gene therapy may be a direct approach for treating this debilitating disorder. In the present study, we first packaged a human DHCR7 construct into adeno-associated virus (AAV) vectors having either type-2 (AAV2) or type-8 (AAV2/8) capsid, and administered treatment to juvenile mice. While a positive response (assessed by increases in serum and liver cholesterol) was seen in both groups, the improvement was greater in the AAV2/8-DHCR7 treated mice. Newborn mice were then treated with AAV2/8-DHCR7 and these mice, compared to mice treated as juveniles, showed higher DHCR7 mRNA expression in liver and a greater improvement in serum and liver cholesterol levels. Systemic treatment did not affect brain cholesterol in any of the experimental groups. Both juvenile and newborn treatments with AAV2/8-DHCR7 resulted in increased rates of weight gain indicating that gene transfer had a positive physiological effect.

Detection and characterization of triamcinolone acetonide metabolites in human urine by liquid chromatography/tandem mass spectrometry after intramuscular administration.

RATIONALE: Glucocorticosteroids are prohibited in sports when used by systemic administrations (e.g. intramuscular, IM), whereas they are allowed using other ways of administration. Strategies to discriminate between administrations routes have to be developed by doping control laboratories. For this reason, the metabolism of triamcinolone acetonide (TA), one of the most used glucocorticosteroids, was studied using liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS). METHODS: Urine samples obtained after IM administration of TA were analyzed using two sample treatments: (a) hydrolysis with ß-glucuronidase enzymes and liquid-liquid extraction under alkaline conditions, and (b) liquid-liquid extraction under acidic conditions. The extracts were analyzed by LC/MS/MS. RESULTS: TA, commercially available metabolites (6ß-hydroxytriamcinolone acetonide, 6ß-OH-TA, and triamcinolone), and their C20-reduced derivatives showed characteristic fragmentation behavior. Besides common product ions and neutral losses for corticosteroids containing fluorine, additional characteristic neutral losses (58 Da, loss of acetone; 44 Da, loss of acetaldehyde) were observed in positive electrospray ionization. Based on that behavior, two complementary approaches were applied to detect TA metabolites: (a) open detection by precursor ion and neutral loss scan methods and (b) targeted detection by selected reaction monitoring methods (SRM) containing theoretical ion transitions of the potential metabolites. Two main compounds, TA and 6ß-OH-TA, and nine minor potential metabolites, were detected by open screening methods. Using SRM, two additional metabolites were detected. Some of the metabolites were characterized using reference standards and, for the rest of metabolites, feasible structures were proposed based on mass spectrometric data. CONCLUSIONS: Metabolites resulting from hydroxylation in C-6, oxidation of the 11-hydroxyl group, reduction of the Δ(4) double bond and oxidation of the side chain were detected. Some of them have not been previously described. Excretion profiles of the detected metabolites after IM administration are presented.

Urinary profile of methylprednisolone and its metabolites after oral and topical administrations.

Methylprednisolone (MP) is prohibited in sports competitions when administered by systemic routes; however its use by topical administration is allowed. Therefore, analytical approaches to distinguish between these different administration pathways are required. A reporting level of 30ng/mL was established for this purpose. However, the suitability of that reporting level for MP is not known. In the present work, excretion profiles of MP and different metabolites after oral and topical administrations have been compared. A method for the quantification of MP and the qualitative detection of fifteen previously reported metabolites has been validated. The method involved an enzymatic hydrolysis, liquid-liquid extraction and analysis by liquid chromatography coupled to tandem mass spectrometry. The method was found to be linear, selective, precise and accurate. The high sensitivity (limit of detection 0.1ng/mL) and linear range (0.1-250ng/mL) achieved allowed for the quantification of MP at both the low concentrations present after topical administration and the high concentrations detected after oral intake. The method was applied to samples collected after oral (4 or 40mg) and topical administration (10mg of MP aceponate/day for 5 consecutive days) to healthy volunteers. After oral administration, MP and all metabolites were detected in urines collected up to at least 36h. Only MP and five metabolites were detected in samples obtained after topical treatment. As expected, concentrations of MP after topical administration were well below current reporting level (30ng/mL), however 3 out of 4 samples in range 8-24h after the low oral dose (4mg) were also below that concentration. Taking into account metabolites detected after both administration routes, metabolites 16ß,17α,21-trihydroxy-6α-methylpregna-1,4-diene-3,11,20-trione (M8) and 17α,20α,21-trihydroxy-6α-methylpregna-1,4-diene-3,11-dione (M11) are best markers to differentiate between topical and oral administrations. Their signals after topical administration were lower than those obtained in the first 48h after all oral doses.

Discrimination of prohibited oral use from authorized inhaled treatment of budesonide in sports.

BACKGROUND: Budesonide (22(R,S)-16α,17α-butylidenedioxy-11ß,21-dihydroxypregna-1,4-diene-3,20-dione) (BUD) is a glucocorticoid widely used for the treatment of asthma and rhinitis. Its use in sport competitions is prohibited when administered by oral, intravenous, intramuscular, or rectal routes, but its use by other routes (eg, inhalation) is allowed. The objective of this study was to evaluate the urinary profiles of different metabolites of BUD after oral and inhaled administrations in order to define a criterion to discriminate between forbidden and authorized administrations of the drug. METHODS: A liquid chromatography-tandem mass spectrometry method was validated to quantify BUD, 16α-hydroxy-prednisolone, 6ß-hydroxy-budesonide, and 6α-hydroxy-budesonide and to qualitatively determine 13 additional BUD metabolites. The method was applied to urine samples collected in clinical studies where BUD was administered to healthy volunteers by the oral route (n = 2) and by inhalation for 3 consecutive days followed by a single oral dose (n = 8). RESULTS: Reporting levels of the different metabolites were evaluated in terms of specificity (no false-positive results after inhalation) and sensitivity (no false-negative results after oral intake). CONCLUSION: Taking into consideration the administered doses, the best compromise to discriminate between authorized inhaled administration and forbidden oral intake of BUD was found using a reporting level of 20 ng/mL of metabolite 6ß-hydroxy-budesonide.

Identification of budesonide metabolites in human urine after oral administration.

Budesonide (BUD) is a glucocorticoid widely used for the treatment of asthma, rhinitis, and inflammatory bowel disease. Its use in sport competitions is prohibited when administered by oral, intravenous, intramuscular, or rectal routes. However, topical preparations are not prohibited. Strategies to discriminate between legal and forbidden administrations have to be developed by doping control laboratories. For this reason, metabolism of BUD has been re-evaluated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with different scan methods. Urine samples obtained after oral administration of 3 mg of BUD to two healthy volunteers have been analyzed for metabolite detection in free and glucuronide metabolic fractions. Structures of the metabolites have been studied by LC-MS/MS using collision induced dissociation and gas chromatography-mass spectrometry (GC/MS) in full scan mode with electron ionization. Combination of all structural information allowed the proposition of the most comprehensive picture for BUD metabolism in humans to this date. Overall, 16 metabolites including ten previously unreported compounds have been detected. The main metabolite is 16α-hydroxy-prednisolone resulting from the cleavage of the acetal group. Other metabolites without the acetal group have been identified such as those resulting from reduction of C20 carbonyl group, oxidation of the C11 hydroxyl group and reduction of the A ring. Metabolites maintaining the acetal group have also been identified, resulting from 6-hydroxylation (6α and 6ß-hydroxy-budesonide), 23-hydroxylation, reduction of C6-C7, oxidation of the C11 hydroxyl group, and reduction of the C20 carbonyl group. Metabolites were mainly excreted in the free fraction. All of them were excreted in urine during the first 24 h after administration, and seven of them were still detected up to 48 h after administration for both volunteers.

Using complementary mass spectrometric approaches for the determination of methylprednisolone metabolites in human urine.

RATIONALE: The metabolism of methylprednisolone is revisited in order to find new metabolites that could be important for distinguishing between different routes of administration. Recently developed liquid chromatography/tandem mass spectrometry (LC/MS/MS) strategies for the detection of corticosteroid metabolites have been applied to the study of methylprednisolone metabolism. METHODS: The structures of these metabolites were studied using two complementary mass spectrometric techniques: LC/MS/MS in product ion scan mode with electrospray ionization and gas chromatography/mass spectrometry (GC/MS) in full scan mode with electron ionization. Metabolites were also isolated by semipreparative liquid chromatography fractionation. Each fraction was divided into two aliquots; one was studied by LC/MS/MS and the other by GC/MS after methoxyamine-trimethylsilyl derivatization. RESULTS: The combination of all the structural information allowed us to propose a comprehensive picture of methylprednisolone metabolism in humans. Overall, 15 metabolites including five previously unreported compounds have been detected. Specifically, 16ß,17α,21-trihydroxy-6α-methylpregna-1,4-diene-3,11,20-trione, 17α,20ß,21-trihydroxy-6α-methylpregna-1,4-diene-3, 11-dione, 11ß,17α,21-trihydroxy-6α-hydroxymethylpregna-1,4-diene-3,20-dione, 11ß,17α,20ξ,21-tetrahydroxy-6α-hydroxymethylpregna-1,4-diene-3-one, and 17α,21-dihydroxy-6α-hydroxymethylpregna-1,4-diene-3,11,20-trione are proposed as feasible structures for the novel metabolites. In addition to the expected biotransformations: reduction of the C20 carbonyl, oxidation of the C11 hydroxy group, and further 6ß-hydroxylation, we propose that hydroxylation of the 6α-methyl group can also take place. CONCLUSIONS: New metabolites have been identified in urine samples collected after oral administration of 40 mg of methylprednisolone. All identified metabolites were found in all samples collected up to 36 h after oral administration. However, after topical administration of 5 g of methylprednisolone aceponate, neither the parent compound nor any of the metabolites were detected.