Inter-individual variation of the urinary steroid profiles in Swedish and Norwegian athletes.

The steroidal module of the Athlete Biological Passport (ABP) aims to detect doping with endogenous steroids, e.g. testosterone (T), by longitudinally monitoring several biomarkers. These biomarkers are ratios combined into urinary concentrations of testosterone and metabolically related steroids. However, it is evident after 5 years of monitoring steroid passports that there are large variations in the steroid ratios complicating its interpretation. In this study, we used over 11000 urinary steroid profiles from Swedish and Norwegian athletes to determine both the inter- and intra-individual variations of all steroids and ratios in the steroidal passport. Furthermore, we investigated if the inter-individual variations could be associated with factors such as gender, type of sport, age, time of day, time of year, and if the urine was collected in or out of competition. We show that there are factors reported in today's doping tests that significantly affect the steroid profiles. The factors with the largest influence on the steroid profile were the type of sport classification that the athlete belonged to as well as whether the urine was collected in or out of competition. There were also significant differences based on what time of day and time of year the urine sample was collected. Whether these significant changes are relevant when longitudinally monitoring athletes in the steroidal module of the ABP should be evaluated further.

Sensitivity of doping biomarkers after administration of a single dose testosterone gel.

Micro-doping with testosterone (T) is challenging to detect with the current doping tests. Today, the methods available to detect T are longitudinally monitoring of urine biomarkers in the Athlete Biological Passport (ABP) and measuring the isotopic composition of excreted biomarkers to distinguish the origin of the molecule. In this study, we investigated the detectability of a single dose of 100 mg T gel in 8 healthy male subjects. We also studied which biomarkers were most sensitive to T gel administration, including blood biomarkers. The ABP successfully detected T gel administration in all 8 subjects. The most sensitive ratio was 5αAdiol/E, however, all ratios showed atypical findings. Isotope ratio mass spectrometry (IRMS) was performed on 5 subjects and only 2 met all the criteria for a positive test according to the rules set by the World Anti-Doping Agency (WADA). The other 3 showed inconclusive results. Other markers that were affected by T gel administration, not used for this detection today, were serum dihydrotestosterone (DHT) and T as well as reticulocyte count and percentage in whole blood. miRNA-122 was not significantly affected by the single T dose. A single dose of 100 mg T gel is possible to detect with today's doping tests. Since a single dose of T gel has an impact on some hematological biomarkers, access to both modules of the ABP when evaluating the athletes' profiles will increase the possibility to detect micro-doses of T. In addition, serum DHT and T may be a useful addition to the future endocrine module of the ABP.

Discordant genotyping results using DNA isolated from anti-doping control urine samples.

The UGT2B17 gene deletion polymorphism is known to correlate to urinary concentration of testosterone-glucuronide and hence this genotype exerts a large impact on the testosterone/epitestosterone (T/E) ratio, a biomarker for testosterone doping. The objective of this study was to assess if DNA isolated from athletes' urine samples (n = 713) obtained in routine doping controls could be targeted for genotyping analysis for future integration in the athlete's passport. A control population (n = 21) including both urine and blood DNA was used for genotyping concordance test. Another aim was to study a large group (n = 596) of authentic elite athletes in respect of urinary steroid profile in relation to genetic variation. First we found that the genotype results when using urine-derived DNA did not correlate sufficiently with the genotype obtained from whole blood DNA. Secondly we found males with one or two UGT2B17 alleles had higher T/E (mean 1.63 ± 0.93) than females (mean 1.28 ± 1.08), p˂0.001. Unexpectedly, we found that several male del/del athletes in power sports had a T/E ˃1. If men in power sport exert a different urinary steroid profile needs to be further investigated. The other polymorphisms investigated in the CYP17A1, UGT2B7 and UGT2B15 genes did not show any associations with testosterone and epitestosterone concentrations. Our results show that genotyping using urine samples according to our method is not useful in an anti-doping setting. Instead, it is of importance for the anti-doping test programs to include baseline values in the ABP to minimize any putative impact of genotype. Copyright © 2016 John Wiley & Sons, Ltd.

Urinary steroid profile in females - the impact of menstrual cycle and emergency contraceptives.

Today's doping tests involving longitudinal monitoring of steroid profiles are difficult in women. Women have more complex hormonal fluctuations than men and commonly take drugs such as hormonal contraceptives that are shown to affect biomarkers used in these doping tests. In this study, we followed six women's urinary steroid profile during one menstrual cycle, including both glucuronides and sulfate conjugated fractions. Additionally, we studied what happens to the steroidal module of the Athlete Biological Passport (ABP) after administration of an emergency contraceptive (levonorgestrel, NorLevo®). The study shows that there are large individual variations in all metabolites included in the ABP and that the administration of emergency contraceptives may lead to suspicious steroid profile findings in the ABP. Urinary epitestosterone concentration increased during the menstrual cycle, leading to a decrease in the testosterone/epitestosterone ratio. The ratios followed in the ABP varied widely throughout the menstrual cycle, the coefficient of variation (CV) ranging from 4 to 99%. There was a 3-fold decrease in epitestosterone 24 h post administration of the emergency contraceptive pill and androsterone, etiocholanolone, and 5ß- androstan-3α,17ß-diol concentrations decreased about 2-fold. When analyzed with the ABP software, one of the six women had an atypical profile after taking the emergency contraceptive. Furthermore, we could not find any alterations in excretion routes (i.e., if the metabolites are excreted as glucuronide or sulfate conjugates) during the menstrual cycle or after administration of emergency contraceptive, indicating no direct effect on phase II enzymes. Copyright © 2016 John Wiley & Sons, Ltd.

Dose-dependent testosterone sensitivity of the steroidal passport and GC-C-IRMS analysis in relation to the UGT2B17 deletion polymorphism.

The newly implemented Steroid Module of the Athlete Biological Passport has improved doping tests for steroids. A biomarker included in this passport is the urinary testosterone glucuronide to epitestosterone glucuronide (T/E) ratio, a ratio greatly affected by a deletion polymorphism in UGT2B17. Suspect urine doping tests are further analyzed with gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) to determine the origin of the androgen. In this study, we investigated the sensitivity of the steroidal module and the IRMS analysis, in subjects administered with three doses of testosterone enanthate (500, 250, and 125 mg), in relation to the UGT2B17 polymorphism. All subjects carrying the UGT2B17 enzyme reached the traditionally used threshold, a T/E ratio of 4, after all three administered doses, whereas none of the subjects devoid of this enzyme reached a T/E of 4. On the other hand, using the athlete biological passport and IRMS analysis, all three doses could be detected to a high degree of sensitivity. The concentrations of all steroids included in the steroidal module were dose dependently increased, except for epitestosterone which decreased independent of dose. The decrease in epitestosterone was significantly associated with circulatory levels of testosterone post dose (rs =0.60 and p=0.007). In conclusion, these results demonstrate that administration of a single dose of 125-500 mg testosterone enanthate could be detected using the athlete biological passport, together with IRMS. Since IRMS is sensitive to testosterone doping independent of UGT2B17 genotype, also very small changes in the steroidal passport should be investigated with IRMS.

The impact of genetics and hormonal contraceptives on the steroid profile in female athletes.

The steroid module of the Athlete Biological Passport, the newest innovation in doping testing, is currently being finalized for implementation. Several factors, other than doping, can affect the longitudinal steroid profile. In this study, we investigated the effect of hormonal contraceptives (HC) as well as the effect of three polymorphisms on female steroid profiles in relation to doping controls. The study population consisted of 79 female elite athletes between the ages of 18 and 45. HC were used by 32% of the subjects. A full urinary steroid profile was obtained using World Anti-Doping Agency accredited methods. In addition all subjects were genotyped for copy number variation of UGT2B17 and SNPs in UGT2B7 and CYP17. Subjects using HC excreted 40% less epitestosterone as compared to non-users (p = 0.005) but showed no difference in testosterone excretion. When removing individuals homozygous for the deletion in UGT2B17, the testosterone to epitestosterone (T/E) ratio was 29% higher in the HC group (p = 0.016). In agreement with previous findings in men, copy number variation of UGT2B17 had significant effect on female urinary testosterone excretion and therefore also the T/E ratio. Subjects homozygous for the T allele of CYP17 showed a lower urinary epitestosterone concentration than the other CYP17 genotypes. It is of great importance that the athlete's steroidal passport can compensate for all possible normal variability in steroid profiles from women. Therefore, considering the large impact of HC on female steroid profiles, we suggest that the use of HC should be a mandatory question on the doping control form.

Non-steroidal anti-inflammatory drugs do not influence the urinary testosterone/epitestosterone glucuronide ratio.

The UDP Glucuronosyl Transferase (UGT) enzymes are important in the pharmacokinetics, and conjugation, of a variety of drugs including non-steroidal anti-inflammatory drugs (NSAIDs) as well as anabolic androgenic steroids (AAS). Testosterone glucuronidation capacity is strongly associated with a deletion polymorphism in the UGT2B17 gene. As the use of high doses of NSAIDs has been observed in athletes there is a risk for a drug-drug interaction that may influence the doping tests for AAS. In vitro studies show inhibitory potential on UGT2B7, 2B15, and 2B17 enzymes by NSAIDs. The aim of this study was to investigate if concomitant use of NSAIDs and a single dose of testosterone enanthate would affect the excretion rate of testosterone and epitestosterone glucuronide (TG and EG) as well as the T/E ratio, thereby affecting the outcome of the testosterone doping test. The study was designed as an open, randomized, cross-over study with subjects being their own control. The 23 male healthy volunteers, with either two, one or no allele (ins/ins, ins/del, or del/del) of the UGT2B17 gene, received the maximum recommended dose of NSAID (Ibuprofen or Diclofenac) for 6 days. On day three, 500 mg of testosterone enanthate was administered. Spot urine samples were collected for 17 days. After a wash-out period of 4 months the volunteers received 500 mg testosterone enanthate only, with subsequent spot urine collection for 14 days. The glucuronides of testosterone and epitestosterone were quantified. NSAIDs did not affect the excretion of TG or EG before the administration of testosterone. The concomitant use of NSAIDs and testosterone slightly increased the TG excretion while the EG excretion was less suppressed compared to testosterone use only. The effects of the NSAIDs on the TG and EG excretion did not differ between the UGT2B17 genotype groups. In conclusion, the outcome of testosterone doping tests does not seem to be affected by the use of NSAIDs.

Basal and Regulatory Promoter Studies of the AKR1C3 Gene in Relation to Prostate Cancer.

BACKGROUND: Human 17ß-hydroxysteroid dehydrogenase type 5 (17ß-HSD5) formally known as aldo-keto reductase 1C3 (AKR1C3) play a major role in the formation and metabolism of androgens. The enzyme is highly expressed in the prostate gland and previous studies indicate that genetic variation in the AKR1C3 gene may influence the prostate volume and risk of prostate cancer. AIM: Here we aimed to further study the genetic regulation of AKR1C3 and its putative role in prostate cancer. EXPERIMENTS: A previously identified promoter polymorphism (A>G, rs3763676) localized at -138 from the translational start site were studied in relation to prostate cancer in a Swedish population based case-control study including 176 patients diagnosed with prostate cancer and 161 controls. Moreover, we have studied the basal and androgen induced promoter activity of the AKR1C3 gene. Expression studies with AKR1C3 promoter reporter constructs were performed in HepG2 and DSL2 cells. RESULTS: We found that carriers of the promoter A-allele had a borderline significant decreased risk of prostate cancer (OR = 0.59; 95% CI = 0.32-1.08). We also show that dihydrotestosterone (DHT) induced the promoter activity of the A-allele 2.2-fold (p = 0.048). Sp3 seem to play an important role in regulating the transcription activity of AKR1C3 and site-directed mutagenesis of a GC-box 78 base-pair upstream the ATG-site significantly inhibited the basal AKR1C3 promoter activity by 70%. CONCLUSION: These results further supports previous findings that the A>G promoter polymorphism may be functional and that AKR1C3 plays a critical role in prostate carcinogenesis. Our findings also show that the members of Sp family of transcription factors are important for the constitutive expression of AKR1C3 gene.

Androgen sulfation in healthy UDP-glucuronosyl transferase 2B17 enzyme-deficient men.

CONTEXT: The conspicuous interindividual differences in metabolism and urinary excretion of testosterone and its metabolites make it challenging to reveal testosterone doping. The variation in testosterone glucuronide excretion is strongly associated with a deletion polymorphism in the uridine diphosphate-glucuronosyltranferase (UGT) 2B17 gene. OBJECTIVE: The objective of the study was to identify additional biomarkers to detect testosterone abuse and to elucidate alternative pathways for testosterone elimination in individuals devoid of the UGT2B17 enzyme. For this purpose a new ultraperformance liquid chromatographic tandem mass spectrometric method for simultaneous determination of 10 different sulfo- and glucuronide-conjugated steroids was developed. PARTICIPANTS: Fifty-four healthy male volunteers with two, one, or no allele (ins/ins, ins/del, or del/del) of the UGT2B17 gene participated in the study. INTERVENTION: Intervention included a single im dose of 500 mg testosterone enanthate. MAIN OUTCOME MEASURES: Urinary sulfo- and glucuronide-conjugated steroids were measured. RESULTS: Testosterone sulfate levels decreased in all individuals after the dose. The individual differences in the excretion of all sulfated metabolites were large. Thus, these metabolites will not serve as appropriate biomarkers for testosterone abuse. However, androsterone glucuronide excretion increased in all of our study subjects after the testosterone dose. Etiocholanolone sulfate was excreted at significantly higher levels in UGT2B17 del/del individuals. CONCLUSION: We propose that the androsterone glucuronide to epitestosterone glucuronide ratio may serve as a complementary biomarker to reveal testosterone abuse.

Bioavailability of testosterone enanthate dependent on genetic variation in the phosphodiesterase 7B but not on the uridine 5'-diphospho-glucuronosyltransferase (UGT2B17) gene.

OBJECTIVE: To study the disposition of serum testosterone and seven of its metabolites before and after 2 days of an intramuscular dose (500 mg) of testosterone enanthate in relation to the phosphodiesterase (PDE7B) and the uridine 5'-diphospho-glucuronosyltransferase (UGT2B17) genotypes. METHODS: Patients were genotyped for UGT2B17 deletion polymorphism and single nucleotide polymorphisms in the PDE7B gene. The involvement of PDE7B in hydrolysis of enanthate was assessed in human liver homogenates. RESULTS: Genetic variation in the PDE7B gene was found to be associated with the serum level of testosterone. Individuals homozygous for PDE7B rs7774640 G allele had a smaller increase (2.5-fold) in the serum testosterone levels compared with carriers of the A allele (3.9-fold, P=0.0006). In addition, genetic variation in the PDE7B gene significantly influences the testosterone/epitestosterone ratio, a biomarker of testosterone doping. Our in-vitro incubation studies confirmed that PDE7B serves as a catalyst of the hydrolysis of testosterone enanthate. The UGT2B17 deletion polymorphism did not show any significant association with serum testosterone levels or the other androgen metabolites investigated. CONCLUSION: We have shown that PDE7B is involved in the hydrolysis of testosterone enanthate and that genetic variation in the PDE7B gene is a determinant of the systemic levels of testosterone after administration of testosterone enanthate. It is reasonable to believe that the genetic variation in testosterone bioavailability may be correlated to varying effects of this androgen, whether it is used for replacement therapy or abused in doping. Thus our results may be important to consider in doping test programmes and in therapeutics with androgens and other esterified drugs.

Genetic variation in androgen disposition: implications in clinical medicine including testosterone abuse.

BACKGROUND: Testosterone replacement therapy in hypogonadal men has been used for > 60 years. The use of testosterone substitution is continuously growing and is given to aging men to improve the quality of life. Because testosterone use is associated with muscle strength enhancing effects, it has become a popular drug to abuse. Doping with anabolic steroids, such as testosterone, is a severe challenge to the vision, moral and ethics in sports and has also become a significant and increasing problem in society. OBJECTIVE: The primary aim of this review is to summarize and discuss the contribution of genetic components to inter-individual variation in androgen disposition. CONCLUSION: Genetic variation has a large impact on androgen disposition. This variation is of the utmost importance for the interpretation of doping test results and may modulate the effects of testosterone replacement therapy and testosterone doping.