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Publication
Journal: Endocrinology
May/5/1975
Abstract
A continuous flow incubation (perifusion) system was used to examine the effect of testosterone (T) and three of its 5alpha-reduced metabolites, dihydrotestosterone (DHT), 5alpha-androstane-3alpha, 17beta-diol (3alpha-Adiol) and its 3beta-epimer (3beta-Adiol) on LH and FSH release, induced by hypothalamic extract (HE). In the absence of steroids, successive identical pulses of HE, of 10 min duration each, administered at hourly intervals over a 8-hr period, caused highly reproducible release of LH and FSH. In experimental perifusions, the amounts of LH and FSH released in response to standard 10-min pulses of HE administered at hourly intervals during the continuous infusion of steroid for 4-6 hr were compared with the responses of the same pituitaries to the standard test pulses of HE given before the start of the steroid infusion and after its cessation. All the androgens tested altered pituitary responsiveness. At the 0.1 and 1.0 mug/ml dose level there were differences between the steroids in the way they influenced the responsiveness of the pituitary overtime. Their effects at these two doses fell into three categories depending on whether there was initially: 1) an augmentation of HE induced LH release (T and 3beta-Adiol), 2) augmentation of both FSH and LH release (DHT), OR 3) NO AUGMENTATION IN THE RELEASE OF EITHer gonadotrophin (3alpha-Adiol). All the androgens ultimately suppressed pituitary responsiveness to HE and all were associated with changes in the ratios of LH and FSH released. When the dose of T and 3 beta-Adiol was raised to 10 mug/ml or that of DHT lowered to 0.01 mug/ml the initial stimulatory phase was not seen. Epitestosterone, the biologically inactive epimer of T, did not alter the responsiveness of the pituitary of HE.
Publication
Journal: Journal of Physiology and Biochemistry
November/15/2010
Abstract
Previous studies with different results have suggested that total and bioavailable testosterone levels are modified by physical exercise. Such changes may be related to modifications in cortisol levels and could be reflected in some urine androgens. To determine how weight lifting training may affect serum and urinary androgens, we measured total serum testosterone (T), cortisol, sex hormone binding globulin (SHBG) and urinary testosterone, epitestosterone, androsterone, and etiocholanolone, in a group of 19 elite weight lifters after 20 weeks of training. SHBG increased (from 27.5 +/- 9.5 to 34.7 +/- 8.1 nM, p < 0.05) whereas T/SHBG decreased significantly (from 1.10 +/- 0.4 to 0.85 +/- 0.3, p < 0.05). Serum total testosterone and cortisol did not change significantly. In urine, androsterone and etiocholanolone decreased significantly, whereas testosterone and epitestosterone remained unchanged. Changes in T/SHBG were related positively with changes in urinary androgens (r = 0.680, p < 0.01), and changes in SHBG were negatively related with changes in urinary androgens (r = -0.578, p < 0.01). These results suggest that intense physical activity may have an influence on the elimination of androgenic hormones due mainly to changes in their transporting protein SHBG.
Publication
Journal: Steroids
June/8/2009
Abstract
Testosterone abuse is conventionally assessed by the urinary testosterone/epitestosterone (T/E) ratio, levels above 4.0 being considered suspicious. A deletion polymorphism in the gene coding for UGT2B17 is strongly associated with reduced testosterone glucuronide (TG) levels in urine. Many of the individuals devoid of the gene would not reach a T/E ratio of 4.0 after testosterone intake. Future test programs will most likely shift from population based- to individual-based T/E cut-off ratios using Bayesian inference. A longitudinal analysis is dependent on an individual's true negative baseline T/E ratio. The aim was to investigate whether it is possible to increase the sensitivity and specificity of the T/E test by addition of UGT2B17 genotype information in a Bayesian framework. A single intramuscular dose of 500mg testosterone enanthate was given to 55 healthy male volunteers with either two, one or no allele (ins/ins, ins/del or del/del) of the UGT2B17 gene. Urinary excretion of TG and the T/E ratio was measured during 15 days. The Bayesian analysis was conducted to calculate the individual T/E cut-off ratio. When adding the genotype information, the program returned lower individual cut-off ratios in all del/del subjects increasing the sensitivity of the test considerably. It will be difficult, if not impossible, to discriminate between a true negative baseline T/E value and a false negative one without knowledge of the UGT2B17 genotype. UGT2B17 genotype information is crucial, both to decide which initial cut-off ratio to use for an individual, and for increasing the sensitivity of the Bayesian analysis.
Publication
Journal: Clinical Endocrinology
July/22/2007
Abstract
OBJECTIVE
A diurnal variation in serum testosterone in adult men is well recognized, but whether this occurs during exogenous testosterone administration and the degree to which it is endogenous to the testis is unclear.
METHODS
A clinical research centre investigation of testicular function in normal men.
METHODS
Twenty normal men were recruited, 10 of whom were investigated during administration of testosterone with etonogestrel to suppress gonadotrophin secretion.
METHODS
Hourly blood samples were taken over 24 h for measurement of testosterone, inhibin B, LH, FSH and cortisol. Urinary excretion of testosterone and the testicular steroid epitestosterone was also measured.
RESULTS
In the controls, a diurnal variation in serum testosterone and LH but not FSH was detected. The treated group had similar testosterone concentrations but showed no diurnal variation. Periodicity was also detected in inhibin B concentrations in 5 of the controls and in 9 of the treated group, who also showed synchrony not seen in the controls. Both groups showed diurnal variation in cortisol. Urinary testosterone excretion did not show a diurnal variation in either group, but this was apparent for epitestosterone with a morning peak in both groups despite the markedly lower excretion in the treated men.
CONCLUSIONS
The diurnal variation of testosterone in normal men is due to a change in secretion rather than in clearance and is largely LH driven. An endogenous rhythm in both testicular steroidogenesis (epitestosterone) and Sertoli cell function (inhibin B) is also present.
Publication
Journal: Electrophoresis
February/5/2008
Abstract
ACE is a popular technique for evaluating association constants between drugs and proteins. However, ACE has not previously been applied to study the association between electrically neutral biomolecules and plasma proteins. We studied the affinity between human and bovine serum albumins (HSA and BSA, respectively) and three neutral endogenous steroid hormones (testosterone, epitestosterone and androstenedione) and two synthetic analogues (methyltestosterone and fluoxymesterone) by applying the partial-filling technique in ACE (PF-ACE). From the endocrinological point of view, the distribution of endogenous steroids among plasma components is of great interest. Strong interactions with albumins suppress the biological activity of steroids. Notable differences in the association constants were observed. In the case of the endogenous steroids, the interactions between testosterone and the albumins were strongest, and those between androstenedione and the albumins were substantially weaker. The association constants, K(b), for testosterone, epitestosterone and androstenedione and HSA at 37 degrees C were 32 100 +/- 3600, 21 600 +/- 1500 and 13 300 +/- 1300 M(-1), respectively, while the corresponding values for the steroids and BSA were 18 800 +/- 1500, 14 000 +/- 400 and 7800 +/- 900 M(-1). Methyltestosterone was bound even more strongly than testosterone, while fluoxymesterone was only weakly bound by the albumins. Finally, the steroids were separated by PF-ACE with HSA and BSA used as resolving components.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
May/18/1994
Abstract
The ratio of urinary testosterone (u-T) to epitestosterone (T/EpiT) is used to disclose testosterone (T) administration in the doping control of sports, and a ratio greater than 6 constitutes an offence. Nevertheless, the possibility of biological outliers must not be discounted, and the use of ketoconazole has been suggested for a dynamic test to distinguish between such athletes and those using T. In this investigation, ketoconazole was administrated to three groups of T-pretreated and two groups of untreated healthy male subjects. The subjects in one of the pretreated groups were patients with mild hypogonadism. One untreated group consisted of athletes that had been tested three times with high urinary T/EpiT levels. The effects of ketoconazole administration on serum T (s-T) level and urinary T/EpiT ratio were monitored every 2 h for an 8-h period and clearly separated T-pretreated and untreated subjects into two clusters (P < 0.0001). The T/EpiT ratio increased and the s-T level remained unchanged in pretreated individuals during the ketoconazole test, whereas T/EpiT decreased by 60% and s-T by almost 90% in untreated subjects. The statistical power of the test increased by using several time points and combining the urinary T/EpiT with the s-T data. In conclusion, the ketoconazole test is suitable as a supportive dynamic test for the urinary T/EpiT ratio measurements in the doping control of athletes.
Publication
Journal: Human Reproduction
November/19/1997
Abstract
Administration of supraphysiological doses of testosterone to normal men causes inhibition of spermatogenesis, but while most become azoospermic, 30-55% maintain a low rate of spermatogenesis. We have investigated whether there are differences in endogenous androgen production, of testicular and adrenal origin, which may be related to the degree of suppression of spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m. injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic, while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a specific testicular product, was reduced to <10% of pretreatment values, with no differences between the groups. Similar results were obtained for other markers of testicular steroidogenesis. Urinary and plasma adrenal androgens were also reduced during TE treatment: a statistically significant decrease in both (P < 0.001 and P < 0.05 respectively) was seen in the azoospermic but not oligozoospermic responders. These results suggest that testicular steroidogenesis is decreased to <10% by the administration of supraphysiological doses of exogenous testosterone. Differences in the degree of ongoing steroidogenesis in the testis do not appear to account for incomplete suppression of spermatogenesis, thus differences in androgen metabolism may underlie this heterogeneous response. A small but significant reduction in secretion of adrenal androgens was also detectable, the relevance of which is unclear.
Publication
Journal: Journal of chromatography
August/17/1989
Abstract
The analytical and methodological imperatives for large-scale and routine gas chromatographic-mass spectrometric screening of anabolic steroid urinary metabolites are described. Several aspects of their isolation, enzymatic hydrolysis, derivatization and metabolism in humans are discussed. Gas chromatographic-mass spectrometric data illustrating artifacts arising from enzymatic hydrolysis of 3 beta-ol-5-en steroids, and describing new metabolites of boldenone, methanedienone and stanozolol, as well as the conversion of norethisterone into 19-nortestosterone metabolites through de-ethylation at C-17, are presented. The analytical approach developed for gas chromatographic-mass spectrometric screening of anabolic steroids is based on the sequential selection-ion monitoring of specific and discrete ion groups characteristic to the steroids of interest under high-resolution chromatographic conditions. The major analytical and methodological requirements necessary to provide irrefutable evidence, in the case where the presence of a synthetic anabolic steroid or a testosterone to epitestosterone ratio higher than 6:1 is suspected in a given urine specimen, are also discussed.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/1/1966
Publication
Journal: Journal of chromatography. B, Biomedical sciences and applications
July/19/1999
Abstract
We propose a new screening method for testosterone (T) doping in sport. The current method for detecting T administration is based on finding a T to epitestosterone ratio (T/E) in urine that exceeds six. The difficulties with T/E are that T administration does not always result in a T/E>6 and that a rare individual will have T/E>6 in the absence of T administration. Our previous studies reveal that carbon isotope ratio helps to determine the origin of the urinary T because the values for T and its metabolites decrease after the administration of exogenous T. In this study, we present a rapid and efficient screening sample preparation method based on three successive liquid-solid extractions, deconjugation with E. coli beta-glucuronidase after the first extraction, acetylation after the second extraction, and a final extraction of the acetates. The 13C/12C of two T metabolites (5beta-androstane-3alpha,17beta-diol and 5alpha-androstane-3alpha,17beta-diol) and one pregnanediol as endogenous reference (5beta-pregnane-3alpha,20alpha-diol) was measured by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) on 10 ml of urine collected from 10 healthy men before and after T administration. Following T administration, the 13 C/12C of 5beta-androstane-3alpha,17beta-diol diacetate and 5alpha-androstane-3alpha,17beta-diol diacetate declined significantly from -26.2 per thousand to -30.8 per thousand and from -25.2 per thousand to -29.9 per thousand, respectively and the 13C/12C of 5beta-pregnane-3alpha,20alpha-diol diacetate was unchanged. In addition, the ratio of androstanediols to pregnanediol increased in the post-T urines.
Publication
Journal: Journal of chromatography. B, Biomedical applications
April/10/1997
Abstract
In connection with a national anti-doping control program, including analysis of 8946 urine samples, 28 athletes were found to have delivered samples free from xenobiotic anabolic steroids but with an increased testosterone/epitestosterone (T/E) ratio >> 6). Unannounced testing of the above athletes produced 2-4 additional urine samples during the next 2-3 months. A low degree of variation of the T/E ratio, with a C.V. below 30% was found in 17 of the subjects whereas 10 had a C.V. varying from 31% to 43%. One subject with a high urinary T/E ratio (10.5) had a C.V. of this ratio of 126% and also an extremely high ratio between testosterone and LH in urine. It has been reported that non-users of testosterone have T/E ratios fluctuating around a mean with a C.V. that will not exceed 30%. We found that administration of testosterone to seven healthy volunteers resulted in urinary T/E ratios that varied with a C.V. ranging from 67% to 130% during the following 4 weeks. It is concluded that among the above 28 cases, only one can be regarded as a clear case of testosterone doping. Although the vast majority of Swedish athletes have urinary T/E ratios below six, there is a subfraction with a constant higher ratio, possibly due to genetic factors.
Publication
Journal: Drug Testing and Analysis
August/26/2013
Abstract
Ethnicity has been found to influence urinary testosterone glucuronide to epitestosterone glucuronide (T/E) ratios among athletes. Uridine diphospho-glucuronosyltransferase 2B17 (UGT2B17) is the most active enzyme in testosterone glucuronidation. UGT2B17 polymorphism analysis is rarely performed in Japanese athletes, and the influence of testosterone administration on steroid profiles and carbon isotope ratios, according to gene polymorphisms, in Asians remains unknown. The prevalence of UGT2B17 genotypes and urinary androgenic steroid profiles, classified according to UGT2B17 genotypes, was investigated in Japanese athletes (255 male and 256 female). Testosterone enanthate (100 mg) was administered intramuscularly to Japanese female volunteers (del/del: n = 6, del/ins: n = 3, ins/ins: n = 1). The distribution rates of the UGT2B17 del/del genotype in Japanese male and female athletes were 74.5% and 60.2%, respectively. The ins/ins genotype was detected in only three male (1.2%) and seven female (2.7%) athletes. The prevalence of the UGT2B17 deletion genotype was extremely high in Japanese athletes. The T/E ratio in the del/del group was significantly lower than that in the other groups. After testosterone was administered to female volunteers, the T/E ratios for the del/del individuals failed to reach the positivity criterion of 4. By contrast, in all of the del/del subjects, the gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS) analysis successfully fulfilled the positivity criterion. The overall result has demonstrated the limited effectiveness of population-based T/E ratios in screening tests for testosterone use. Subject-based steroid profiling with UGT2B17 genotyping will be an effective strategy for detecting testosterone misuse.
Publication
Journal: Steroids
March/31/2002
Abstract
Orally administered testosterone undecanoate (TU), an anabolic, androgenic steroid, can potentially be abused by athletes. Indirect evidence for detecting oral TU intake could be deduced from the changes in steroid profile post-administration. Direct evidence could be obtained by detection of unchanged TU in plasma. To this end, both urinary and plasma steroid profiles of six healthy male subjects given a single oral dose of 120 mg of TU were studied by gas chromatography/mass spectrometry (GC/MS) and gas chromatography/tandem mass spectrometry (GC/MS/MS). The increased concentration of glucuronidated testosterone in plasma appears to be the most characteristic sign of oral TU intake. The testosterone glucuronide (TG)/nonconjugated testosterone (T) ratio, TG/17-hydroxyprogesterone (17OHP) ratio, and TG/luteinizing hormone (LH) ratio were observed to be significantly elevated above their basal levels for 10 h, 10 h, and 6 h, respectively. Urinary ratios of TG/epitestosterone glucuronide (EG) were found to be higher than the cut-off value of 6 for the period 4 approximately 8 h post-administration, but only in three subjects. One subject failed to respond with respect to all of the above-mentioned indirect markers, as TG was not significantly increased in either plasma or urine. Unchanged TU was directly detected in plasma of all six subjects from 1 approximately 1.5 h to 4 approximately 6 h after oral TU intake by GC/MS/MS, providing unequivocal proof of exogenous testosterone intake. Distinct and complementary markers for detecting oral TU intake could be obtained from plasma and urine, respectively.
Publication
Journal: International Journal of Sports Medicine
January/12/1997
Abstract
There is a potential need for the official criterion of testosterone abuse in sport (the urinary concentration ratio of testosterone glucuronide/epitestosterone glucuronide, TG/EG>> 6) to be backed-up by some complementary markers, more particularly in cases of physiologically high TG/EG and when there is suspicion of joint administration of testosterone and epitestosterone. Testosterone, epitestosterone, their glucuro- and sulfoconjugates, 5-androstene-3 beta, 17 alpha-diol glucuronide and 17-hydroxyprogesterone have been analysed by isotope dilution-gas chromatography-mass spectrometry in plasma and urine of seven subjects supplemented with a single oral dose of undecanoates of testosterone and epitestosterone (respectively 40 mg and 1.5 mg). Adequate plasma criteria for testosterone abuse were the ratios of testosterone glucuronide/17-hydroxyprogesterone and testosterone glucuronide/testosterone which increased significantly above basal values for up to 10 h. The same trend was observed for the ratio of urinary glucuronides of testosterone/5-androstene-3 beta, 17 alpha-diol, while TG/EG was not affected by simultaneous administration of epitestosterone. One subject with low basal TG/EG failed to respond to testosterone administration by any significant increase of analysed parameters.
Publication
Journal: Journal of Endocrinology
January/9/1992
Abstract
Abnormal ratios of testosterone to epitestosterone (T/E) and testosterone to LH (T/LH) in the urine of male athletes are indicative of testosterone administration. The T/E ratio has been adopted by the International Olympic Committee as the sole criterion used in the detection of testosterone administration. An athlete is usually considered to have failed a drug test if the urinary T/E ratio is greater than 6. Human chorionic gonadotrophin (hCG) has been used by some male athletes to stimulate testicular secretion of testosterone. The purpose of this investigation was to examine whether the urinary T/E ratio can remain unaffected by administration of hCG to normal adult males. Administration of hCG resulted in large increases in serum testosterone concentrations and urinary T/LH ratios but small changes in urinary T/E ratios of two subjects (maximum T/E values observed were 0.8 and 1.2 respectively). These observations suggest that the urinary T/LH ratio is a valuable indicator of hCG as well as of testosterone administration. This study is the first to measure urinary T/LH ratios using the technique of gas chromatography-mass spectrometry for quantification of testosterone, and highly specific monoclonal antibodies for the measurement of LH. An ultrafiltration method is proposed as part of a confirmatory procedure to be adopted in the measurement of urinary gonadotrophins for drug control in sport.
Publication
Journal: Journal of steroid biochemistry
July/1/1987
Abstract
Follicular fluid was aspirated from preovulatory follicles of women under ovarian stimulation for in vitro fertilization and analyzed by a highly specific technique based on gas chromatography-mass spectrometry associated with stable isotope dilution. 19-Nortestosterone and 19-norandrostenedione were identified and quantified for the first time in human follicular fluid. There was a strong positive correlation between 19-nortestosterone and estradiol-17 beta and between 19-norandrostenedione and estrone concentrations, thus indicating a common cellular origin. The accumulation of 19-norsteroids in follicular fluid confirms that they are weakly active intermediates in the multistep enzymatic conversion of androgen to estrogen. Testosterone concentrations were significantly lower than those obtained by radioimmunoassay; cross-reaction with substantially higher levels of 19-nortestosterone seems to be at the origin of this discrepancy. Androstenedione concentrations were similar to those reported in the literature and it was therefore confirmed that an estradiol/androstenedione concentration ratio above 20 is favourable for oocyte cleavage. Other and some newly estimated androgens are: testosterone sulfate, 5-androstene-3 beta, 17 beta-diol 3-sulfate and disulfate, dihydrotestosterone sulfate, epitestosterone, 19-hydroxyandrostenedione, 5 alpha-androstane-3 alpha, 17 beta-diol, 5 alpha-androstane-3 beta, 17 beta-diol, 5 alpha-androstane-3,17-dione and androsterone. Dehydroepiandrosterone sulfate was by far the most abundant androgen in this type of follicles.
Publication
Journal: British Journal of Sports Medicine
July/30/2006
Abstract
OBJECTIVE
The long term effects (>20 years) of anabolic-androgenic steroid (AAS) use on plasma concentrations of homocysteine (HCY), folate, testosterone, sex hormone binding globulin (SHBG), free androgen index, urea, creatinine, haematocrit (HCT), vitamin B12, and urinary testosterone/epitestosterone (T/E) ratio, were examined in a cohort of self-prescribing bodybuilders.
METHODS
Subjects (n = 40) were divided into four distinct groups: (1) AAS users still using AAS (SU; n = 10); (2) AAS users abstinent from AAS administration for 3 months (SA; n = 10); (3) non-drug using bodybuilding controls (BC; n = 10); and (4) sedentary male controls (SC; n = 10).
RESULTS
HCY levels were significantly higher in SU compared with BC and SC (p<0.01), and with SA (p<0.05). Fat free mass was significantly higher in both groups of AAS users (p<0.01). Daily energy intake (kJ) and daily protein intake (g/day) were significantly higher in SU and SA (p<0.05) compared with BC and SC, but were unlikely to be responsible for the observed HCY increases. HCT concentrations were significantly higher in the SU group (p<0.01). A significant linear inverse relationship was observed in the SU group between SHBG and HCY (r = -0.828, p<0.01), indicating a possible influence of the sex hormones in determining HCY levels.
CONCLUSIONS
With mounting evidence linking AAS to adverse effects on some clotting factors, the significantly higher levels of HCY and HCT observed in the SU group suggest long term AAS users have increased risk of future thromboembolic events.
Publication
Journal: European Journal of Applied Physiology
May/28/2007
Abstract
Performing strength exercise, whether acutely or in a training programme, leads to alterations at the hypothalamic-pituitary-testicular and hypothalamic-pituitary-adrenal axes. One way to evaluate these changes is by analysis of the excretion of steroid hormones in the urine. The present study determined the variations in the urine profile of glucuroconjugated steroids after a single session of strength exercise and after a 4-week programme of strength training. The subjects were a group (n = 20) of non-sportsman male university students who worked out 3 days a week [Monday (M), Wednesday (W) and Friday (F)], performing the exercises at 70-75% of one repetition maximum strength (1-RM). Four urine samples were collected per subject: (A) before and (B) after a standard session prior to initiating the training programme, and (C) before and (D) after the same standard session at the end of the study, and they were assayed by gas chromatography coupled to mass spectrometry. The concentrations of the different hormones were determined relatively to the urine creatinine level (ng steroid/mg creatinine) to correct for diuresis. After the exercise sessions, both before and after the training programme, there was a fall in the urine excretion of androgens and estrogens, but no statistically significant changes in the excretion of tetrahydrocortisol (THF) and tetrahydrocortisone (THE). The anabolic/catabolic hormones ratio also decreased after the acute session, although only androstenodione + dehydroepiandrosterone (DHEA)/THE + THF ratio had a significant decrease (P < 0.05). After the training programme, there was a significant (P < 0.01) improvement in the strength of the muscle groups studied, and an increased urinary excretion of all the androgens with respect to the initial state of repose, with the difference being significant in the case of epitestosterone (Epit) (P < 0.05). The androsterone (A) + etiocholanolone (E)/THE + THF ratio increased significantly (P < 0.05) concerning the initial state. We therefore conclude that subjects suffer variations of the urine profile with regard to the steroid hormones before and after the acute strength sessions and after the training period. The alteration after the training programme seems to be due to the subjects' hypothalamic-hypophysis-testicular and hypothalamic-pituitary-adrenal axes adaptations, which enable them to increase physical strength.
Publication
Journal: Bone
July/17/1997
Abstract
Nonsteroidal antiandrogen casodex and steroidal antiandrogen epitestosterone were administered to intact male mice, and their effect on femoral bones and circulating calcium, phosphate, testosterone, and LH were compared with controls and castrated animals. Pure antiandrogen casodex in a dose used in humans for treatment of prostate cancer decreased the weight of seminal vesicles, organ which is highly sensitive to the androgenic effect, increased insignificantly the concentration of LH and of testosterone, but did not have any effect on bone density or mineral content of bone. Epitestosterone, which not only inhibits the binding of androgens to their receptors but also inhibits the formation of dihydrotestosterone from testosterone, and is reported to interfere with aromatization of testosterone to estrogens, decreased the bone density, ash weight, and calcium and phosphate content of femoral bone tissue significantly, although not to values as low as those seen in castrated animals.
Publication
Journal: Forensic Science International
June/15/2009
Abstract
Doping with endogenous anabolic steroids is one of the most serious issues in sports today. The measurement of anabolic steroid levels in human hair is necessary in order to distinguish between pharmaceutical steroids and natural steroids. This is the first investigation into the physiological concentrations of anabolic steroids in human hair in Chinese subjects. A gas chromatography-tandem mass spectrometry (GC/MS/MS) method was developed for the simultaneous identification and quantitation of five endogenous anabolic steroids (testosterone, epitestosterone, androsterone, etiocholanolone and dehydroepiandrosterone) in hair. After basic hydrolysis, hair samples were extracted with diethyl ether, derivatized and then detected using GC/MS/MS in the multiple-reaction monitoring mode (MRM). The one precursor/two product ion transitions for each anabolic steroid were monitored. The limits of detection for the five endogenous anabolic steroids were in the 0.1-0.2 pg/mg range. All analytes showed good linearity and the extraction recoveries were 74.6-104.5%. Within-day and between-day precisions were less than 20%. This method was applied to the analysis of testosterone, epitestosterone, androsterone, etiocholanolone, and dehydroepiandrosterone in human hair. Full-length hair samples were taken at the skin surface from the vertex of 39 males, 30 females and 11 children from China. None of the subjects were professional athletes. Testosterone and dehydroepiandrosterone were detected in all the hair segments. The physiological concentrations of testosterone were in the range 0.8-24.2 pg/mg, 0.1-16.8 pg/mg and 0.2-11.5 pg/mg in males, females and children, respectively, however, the mean values of dehydroepiandrosterone were much higher than the concentrations of testosterone. These data are suitable reference values and are the basis for the interpretation of results from investigations into the abuse of endogenous anabolic steroids.
Publication
Journal: Journal of Chromatography A
February/18/2009
Abstract
The applicability of comprehensive two-dimensional gas chromatography (GCxGC) for sterol analysis was investigated by separation and identification of endogenous sterols in standards, and spiked in human urine. The modulation temperature was optimized to achieve the best separation and signal enhancement. The separation pattern of trimethylsilyl (TMS) derivatives of sterols was compared on two complementary column sets. Whilst the BPX5/BPX50 column set offers better overall separation, BPX50/BPX5 provides better peak shape and sensitivity. Comparison of the identification power of GCxGC-TOFMS against both the NIST05 MS library and a laboratory created (in-house) TOFMS library was carried out on a free sterols extract of urine, derivatised and spiked at the World Anti-Doping Agency (WADA) limit of 2 ng mL(-1). The average match quality for 19 analysed sterols on the BPX50/BPX5 column set was 950/1000 when searched against the in-house library; only four were identified against the NIST05 library, at a match threshold of 800. The match quality of GCxGC-TOFMS spectra was superior to that for analysis using 1D GC-TOFMS for sterols spiked in urine at 10 ng mL(-1). An r(2)>0.997 was obtained for the concentration range between 0.25 ng mL(-1) and 10 ng mL(-1) for three selected sterols. The lowest limit of detection (LOD) was obtained for estrone (0.1 ng mL(-1)) and the highest LOD was for 5alpha-androstan-3alpha,11beta-diol-17-one, epitestosterone and cholesteryl butyrate (1 ng mL(-1)), using a match threshold of at least 800 and signal-to-noise ratio of at least 10. TOFMS coupled to GCxGC enabled satisfactory identification of sterols in urine at their LOD. A minimum acceptable match (MAM) criterion for urinary sterols using 2D retention times and TOF mass spectra is introduced. This study shows that GCxGC-TOFMS yields high specificity for steroids derived from urine, with detection limits appropriate for use in doping control.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
October/8/2017
Abstract
The sodium-dependent organic anion transporter SOAT/Soat shows highly specific transport activity for sulfated steroids. SOAT substrates identified so far include dehydroepiandrosterone sulfate, 16α-hydroxydehydroepiandrosterone sulfate, estrone-3-sulfate, pregnenolone sulfate, 17β-estradiol-3-sulfate, and androstenediol sulfate. Apart from these compounds, many other sulfated steroids occur in mammals. Therefore, we aimed to expand the substrate spectrum of SOAT and analyzed the SOAT-mediated transport of eight different sulfated steroids by combining in vitro transport experiments in SOAT-transfected HEK293 cells with LC-MS/MS analytics of cell lysates. In addition, we aimed to better understand the structural requirements for SOAT substrates and so selected structural pairs varying only at specific positions: 3α/3β-sulfate, 17α/17β-sulfate, mono-sulfate/di-sulfate, and 17α-hydroxylation. We found significant and sodium-dependent SOAT-mediated transport of 17α-hydroxypregnenolone sulfate, 17β-estradiol-17-sulfate, androsterone sulfate, epiandrosterone sulfate, testosterone sulfate, epitestosterone sulfate, and 5α-dihydrotestosterone sulfate. However, 17β-estradiol-3,17-disulfate was not transported by SOAT.
CONCLUSIONS
SOAT substrates from the group of sulfated steroids are characterized by a planar and lipophilic steroid backbone in trans-trans-trans conformation of the rings and a negatively charged mono-sulfate group at positions 3' or 17' with flexibility for α- or β- orientation. Furthermore, 5α-reduction, 16α-hydroxylation, and 17α-hydroxylation are acceptable for SOAT substrate recognition, whereas addition of a second negatively charged sulfate group seems to abolish substrate binding to SOAT, and so 17β-estradiol-3,17-disulfate is not transported by SOAT.
Publication
Journal: Drug Testing and Analysis
July/18/2017
Abstract
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 5β- androstan-3α,17β-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.
Publication
Journal: Frontiers in Endocrinology
April/29/2014
Abstract
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.
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