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Publication
Journal: General and Comparative Endocrinology
December/12/1989
Abstract
The metabolism of androgens in the testis of the lizard Tiliqua rugosa has been studied in vitro by incubating cellular homogenates with radiolabeled C19-steroid substrates. The identification 17 beta-oxidoreductase and 3 beta-hydroxysteroid dehydrogenase/isomerase activities. Aromatase, 5 alpha-reductase, and 17 alpha/beta-epimerase activities were not detected. The 17 alpha-oxidoreductase activity was temperature dependent (maximal at 32 degrees), while the 17 beta-oxidoreductase activity was temperature independent. Time yield and dual-label studies indicated that testosterone biosynthesis mainly involves the 4-ene pathway (via androstenedione), whereas the formation of epitestosterone uses both the 4-ene and 5-ene (via 5-androstene-3 beta, 17 alpha-diol) pathways. The function of alternative pathways in androgen biosynthesis is discussed, as is the role of temperature in the intratesticular regulation of androgen production.
Publication
Journal: Journal of Immunoassay and Immunochemistry
October/31/2013
Abstract
Polyamidoamine dendrimer (PAMAM) is one of a number of dendritic polymers with precise molecular structure, highly geometric symmetry, and a large number of terminal groups. The polyamidoamine modified silica was synthesized with microwave assisted protocol. Anti-epitestosterone monoclonal antibodies were immobilized onto the PAMAM grafted silica and prepared an off-line immunoextraction column that applied in the extraction of testosterone and epitestosterone. The results showed that the affinity activity of the anti-epitestosterone monoclonal antibodies was remained at high level after immobilization. It was satisfactory to apply this new type of immunoextraction column to analyze testosterone and epitestosterone in spiked urine sample.
Publication
Journal: Steroids
February/2/1968
Authors
Publication
Journal: Steroids
November/4/1969
Publication
Journal: Rivista di ostetricia e ginecologia
January/7/1969
Publication
Journal: American Journal of Obstetrics and Gynecology
July/20/1972
Publication
Journal: Analytical Biochemistry
April/17/1969
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/8/1966
Publication
Journal: Biology of Reproduction
September/29/1972
Publication
Journal: Environmental mutagenesis
April/11/1982
Abstract
Hormonal regulation of dimethylnitrosamine (DMN) metabolism by mouse kidney microsomes was investigated using an in vitro mutagenesis system that detects bioactive metabolites of this procarcinogen by measuring reverse mutation in Salmonella typhimurium his- auxotrophs. Induction of microsomal DMN metabolizing enzymes was androgen-specific. Testosterone and medroxyprogesterone acetate were active inducers, d/1 norgestrel was less active, while epitestosterone, estradiol, and progesterone were ineffective. THe response to testosterone and medroxyprogesterone acetate was time-and dose-dependent. Eleven strains of inbred mice were screened for their response to exogenous testosterone. DMN metabolism was stimulated in all mouse strains except for RF/J mice. Other androgenic end points were responsive in the latter strain, however. These observations suggest that induction of renal microsomal DMN metabolising enzymes is androgen-specific and probably mediated via the androgen receptor. The insensitivity of RF/J mice may be due to a mutation affecting a key step in the enzymatic activation of DMN.
Publication
Journal: Journal of steroid biochemistry
October/7/1986
Abstract
Male and female (WB-C57BL/6)F1 hybrid mice were used. Two testes from neonatal mice were grafted into the spleen of adult male and female mice, and the grafted testes were removed 30 and 60 days after grafting. Normal testes from 30- and 60-day old mice were also used. Testicular homogenates were incubated with [14C]4-androstene-3,17-dione or [3H]progesterone, and enzyme activities per g wet tissue and progesterone metabolism were examined. Activity of 17 alpha-oxidoreductase in the grafted testes in females (20 nmol/g/h) was approx. 10 times the activity in the grafted testes in males or in the normal testes, whereas 17 beta-oxidoreductase activity in the grafted testes in females was the lowest among these testes. The bilateral ovariectomy performed 1 month before the grafting of neonatal testes, artificial cryptorchidism performed at 20 days of age, and estrogen treatment for 10 days by diethylstilbestrol pellets resulted in no significant changes in 17 alpha-oxidoreductase activities in 30- and 60-day old grafted, cryptorchid or normal testes. The major 17-hydroxy-C19-steroids formed in vitro from progesterone by the grafted testes in female mice were testosterone and 17 alpha-hydroxy-4-androsten-3-one (epitestosterone), but the formation of epitestosterone was insignificant in the normal testes. The present results demonstrate for the first time that epitestosterone is formed as one of major C19-steroids in neonatally grafted mouse testes in females but not in those in males or in normal mouse testes. However, the mechanisms remain unexplained.
Publication
Journal: Clinica Chimica Acta
July/7/2013
Abstract
A 19 year old male attended his GP with a history of "fluid retention", lack of libido and erectile dysfunction. He was found to have a high serum testosterone, and a raised luteinising hormone. After further investigations, the patient admitted to taking a supplement called ActivaTe Xtreme, obtained from an internet source, to address his low libido. ActivaTe Xtreme contains active ingredients which increase serum testosterone levels by several independent mechanisms that are not associated with luteinising hormone suppression. Urine analyses for synthetic anabolic steroids were negative, and urinary testosterone, epitestosterone and other androgens were normal. This biochemical pattern is not the same as that seen with anabolic steroids (i.e. raised testosterone, suppressed luteinising hormone and abnormal urine steroid profile). The issue of self medication with performance enhancing compounds needs to be carefully considered in order to avoid expensive and invasive investigations, missing an underlying pathology or misdiagnosing a patient. This case also raises the spectre of yet another "performance enhancing" product that may cause difficulty for those trying to ensure that sport remains on a "hormonally" equal basis.
Publication
Journal: Drug Testing and Analysis
November/13/2017
Abstract
Today's doping tests involve longitudinal monitoring of urinary steroids including the testosterone glucuronide and epitestosterone glucuronide ratio (T/E) in an Athlete Biological Passport (ABP). The aim of this study was to investigate the possible influence of short-term use of codeine on the urinary excretion of androgen metabolites included in the steroidal module of the passport prior to and after the co-administration with testosterone. The study was designed as an open study with the subjects being their own control. Fifteen healthy male volunteers received therapeutic doses of codeine (Kodein Meda) for 6 days. On Day 3, 500 mg or 125 mg of testosterone enanthate (Testoviron®-Depot) was administered. Spot urine samples were collected for 17 days, and blood samples were collected at baseline, 3, 6, and 14 days after codeine intake. The circulatory concentration of total testosterone decreased significantly by 20% after 3 days' use of codeine (p = 0.0002) and an atypical ABP result was noted in one of the subjects. On the other hand, the concomitant use of codeine and testosterone did not affect the elevated urinary T/E ratio. In 75% of the individuals, the concentration of urinary morphine (a metabolite of codeine) was above the decision limit for morphine. One of the participants displayed a morphine/codeine ratio of 1.7 after codeine treatment, indicative of morphine abuse. In conclusion, our study shows that codeine interferes with the endogenous testosterone concentration. As a result, the urinary steroid profile may lead to atypical findings in the doping test.
Publication
Journal: Steroids
September/9/2019
Abstract
Testosterone is one of the most abused pseudo-endogenous anabolic steroids in sport doping. The current method adopted to detect the abuse of testosterone and other pseudo-endogenous steroids (endogenous steroids when administered exogenously) is first based on the longitudinal monitoring of several urinary biomarkers, which constitute the so called "steroidal module" of the Athlete Biological Passport (ABP): atypical samples undergo a confirmation analysis based on the measurement of the 13C/12C isotopic ratio of selected target compounds, to distinguish their endogenous or exogenous origin. At the same time, testosterone administration can be allowed in athletes diagnosed with hypogonadism, provided they are granted a therapeutic use exemption by the relevant medical authority. In this pilot study we have investigated whether the approach based on the preliminary determination of the urinary steroid profile, in the format considered in the steroidal module of the ABP, also integrated with the inclusion of the sulfo-conjugates and of additional target steroids, can retain its validity also in the case of hypogonadal athletes. We have studied the effects of a single low dose (40 mg) of testosterone gel (T-gel) on the urinary concentration of the markers of steroidal module of the ABP, as well as on some additional steroid markers. The study was based on the analysis of urinary samples from 19 non-hospitalized hypogonadal men, 10 of them with late-onset hypogonadism (LOH), collected before, after 4 h and after 24 h the transdermal self-administration of 40 mg of T-gel. None of the patient had any co-morbidities possibly affecting the urinary excretion of the steroidal markers. The steroidal markers were quantified by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) after the enzymatic hydrolysis of the respective glucuro-conjugates and the chemical hydrolysis of the respective sulfo-conjugates. Targeted GC-MS/MS analysis was carried out operating in electron impact (EI) ionization mode, with acquisition in multiple reaction monitoring (MRM) mode. Our preliminary results show that, as expected, the treatment with T-gel leads, in all hypogonadal men, to an increase of the urinary concentration of the glucuro-conjugate metabolites of testosterone and its main metabolites, with special relevance to those with 5α-reduction. Furthermore, samples collected from non-LOH hypogonadal men showed an increase also in the levels of epitestosterone glucuronide, testosterone sulfate and epitestosterone sulfate. Apart from their biochemical and pharmacological relevance, these outcomes could be leveraged to refine the analytical strategy currently followed in the antidoping field for the analysis of the urinary steroidal markers, with potential implications also in other forensic and/or clinical investigations.
Publication
Journal: Kardiologiya
September/24/1979
Abstract
The results of studying the excretion of testosterone and other androgens with the urine after a chorionic gonadotropin load in patients with ischemic heart disease and in persons who had suffered from acute myocardial infarction are discussed. In choriogonin load stimulating the gonads, there is noticeable variability in the excretion of testosterone and epitestosterone, androstenedione, and 7-keto-dehydroepiandrosterone in the urine. The data obtained are evidence of reduced functional reserves of the sex glands in some of the patients.
Publication
Journal: Aging Male
November/29/2006
Abstract
The male aging process is accompanied by changes in the levels of several types of hormones. Falling levels of androgenic-anabolic steroids (total testosterone, free testosterone, biologically accessible testosterone, dehydroepiandrosterone) correspond to a group of symptoms referred to as PADAM syndrome (Partial Androgen Deficiency in the Aging Male). In the case of those carefully examined patients with symptoms of PADAM and proven hypogonadism, administering androgen supplements can alleviate some of the undesirable manifestations. In its literature, the University of St Louis repeatedly refers to its questionnaire as a verbal tool for the detection of possible hypogonadism. The aim of this study was to ascertain to what extent the aging process is evident in hormonal homeostasis detected in laboratory testing, and the extent to which this data is in accord with the evaluation of responses to questions in the University of St Louis questionnaire.
METHODS
216 men aged over 50 years were examined. Measurements were taken of: testosterone; the index of free testosterone; androstenedione; dihydrotestosterone; dehydroepiandrosterone and its sulfate; isomers 7alpha- and 7beta-hydroxydehydroepiandrosterone; epitestosterone; luteinizing hormone (LH); follicle-stimulating hormone (FSH); prolactin; and sexual hormone-binding globulin (SHBG). Evaluations of the patients' responses to the University of St Louis questionnaire were compared with the results of the laboratory tests.
RESULTS
The study confirms that the most prominent phenomenon is that of an age-related decrease in the index of free testosterone, which is indicated in particular by an increase in the level of SHBG, and by a decrease in dehydroepiandrosterone and its derivatives. No significant correlation was found between levels of hormones and single items on the questionnaire, nor with the overall score arrived at by studying the patients' data.
Publication
Journal: Hormone and Metabolic Research
March/10/1997
Abstract
The concentrations of the antiandrogenic endogenous steroid epitestosterone (epiT) and of testosterone, dihydrotestosterone (DHT) and androstenedione in the prostate were determined in tissue samples obtained from 21 patients who underwent suprapubic prostatectomy for benign prostatic hyperplasia. Fifteen patients received no hormonal treatment before surgery and the other 6 patients were pretreated for 8 weeks before surgery with an oral dose of 5 mg/day finasteride. The steroids were extracted and separated by high pressure liquid chromatography and determined by specific radioimmunoassays. The concentration of epiT (mean 58.4 +/- 40.4 S.D., range 14.0-144.0 fmol/mg protein) exceeded that of testosterone and was nearly as high as that of DHT. The prostatic tissue from the patients treated with finasteride for 8 weeks showed a significant decrease not only in DHT but also in androstenedione and epiT, whereas the concentration of testosterone increased significantly.
Publication
Journal: Physiological Research
June/30/2013
Abstract
In order to assess whether intratesticular hormone content may be helpful for prediction of successful conception in men with fertility problems, five sex steroids, testosterone, dihydrotestosterone, androstenedione, estradiol and, for the first time epitestosterone, were measured in testicular tissue obtained by surgical retrieval from total 84 men. The group consisted of non-obstructive azoospermic men, aged 21-67 years who attended the centre for in vitro fertilization. Steroids after ether extraction and solvent partition were separated by high performance liquid chromatography and then measured by specific radioimmunoassays. The values varied considerably with means ± S.D. 2.43±2.47, 0.27±0.24, 0.080±0.13, 0.071±0.089 and 0.31±0.27 for testosterone, dihydrotestosterone, androstenedione, estradiol and epitestosterone, respectively.
Publication
Journal: Problemy Endokrinologii
March/12/1982
Abstract
Biochemical and radioimmunoassay of testosterone content in the blood and urine, epitestosterone and 17-CS level in the urine of 80 boys has shown, that the ovarian androgenic function is reduced in all the forms of cryptorchidism. The potential testis reserves are progressively lowered with the age in patients with bilateral and false retention and remain unchanged in unilateral cryptorchidism. In the absolute majority of patients the change in gonadotropic hormone production is noted, manifesting in the decreased and/or increased LH and FSH content in the blood of different patients, that is seemed to reflect heterogeneity of cryptorchidism pathogenetic forms. The ovarian testosterone production rise after chorionic gonadotropin injection did not inhibit the hypophyseal FSH activity.
Publication
Journal: Rapid Communications in Mass Spectrometry
September/28/2011
Abstract
A simple and accurate liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been developed and validated for the quantitative determination of ephedrine, pseudoephedrine, methylephedrine, cathine, salbutamol, morphine and epitestosterone in human urine. Urine samples were spiked with internal standard and diluted with acetonitrile. After centrifugation, the supernatants were directly analyzed by LC/MS/MS using the selected reaction monitoring (SRM) mode. The linearity, intra- and inter-day precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ) were evaluated and the method was found to be accurate and reproducible for the quantitation of threshold substances. When the method was applied to the analysis of blind urine samples for the proficiency test, the results were close to the nominal concentrations, within 87.7-106.6% of nominal values, suggesting that the developed methods can be successfully applied to routine doping analyses.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
September/7/1995
Abstract
Ten endogenous steroid hormones and metabolites were determined according to the screening procedure for anabolic steroids in spot urine samples from 105 healthy young male athletes (control samples) and 23 males that tested positive for anabolic steroids in the doping control (positive samples). The GC-MS peak areas for each sample were normalized to total area. Multivariate data analysis by Partial Least Square Regression (PLSR) and using a coded Y-variable (positive samples: +1 and control samples -1) allows projection of the most systematic profile structures into a 2D plot revealing a clear distinction between the control and misuser groups. The most important determinants of the location in the loading plot were the ratios of testosterone to epitestosterone and androsterone to etiocholanolone. The ratio between 11-beta-hydroxyandrosterone and 11-beta-hydroxy-etiocholanolone was less important, in accordance with the fact that anabolic-androgenic steroid intake primarily affects the excretion of testosterone from the testis and to a much lesser degree adrenal steroid genesis. We present a preliminary validation of this model (PLS1-DISCRIM) for analysing steroid profiles in doping control samples from several categories of athletes, some of which are suspected for drug misuse, and results from a one dose excretion study in healthy volunteers. Our findings suggest that use of multivariate PLS-regression may give valuable information about anabolic androgenic steroid misuse in sport. When appropriately calibrated, this methodology may delineate drug misusers directly from the screening procedure for anabolic steroids in spot urine tests.
Publication
Journal: Analyst, The
January/23/2000
Abstract
A highly specific method is described for measuring the testosterone:epitestosterone ratio in equine urine by gas chromatography-mass spectrometry (GC-MS) with stable isotope internal standards. The procedure was based on Serdolit Pad-1 resin extraction, enzymatic hydrolysis, and chemical derivatisation prior to instrumental analysis. The mixed derivatives, 3-trimethylsilyl-17-pentafluorophenyldimethylsilyl ether (3-TMS-17-flophemesyl) testosterone and epitestosterone, were found to have excellent analytical properties. The specificity of the derivatisation method exploits a unique feature of steroids: the selective exchange of the alcoholic flophemesyl ether for the trimethylsilyl ether. The sensitivity and specificity of the mixed 3-TMS-17-flophemesyl derivatives allow adequate determinations of testosterone and epitestosterone, even in urine from mares, in 5 ml samples. The repeatability of testosterone and epitestosterone was 6.2 and 5.7%, respectively, and their reproducibility was in the range of 6.4-8.7%.
Publication
Journal: Problemy Endokrinologii
July/12/1972
Publication
Journal: Yao xue xue bao = Acta pharmaceutica Sinica
April/1/1993
Abstract
The trimethylsilylation of testosterone and epitestosterone was discussed in detail in this report. Both derivative conditions under which testosterone and epi-testosterone were prepared into TMS-derivatives in the presence of mercaptoethanol as an antioxidizing agent and method for the analysis of the ratio of testosterone to epi-testosterone in urine, based on GC-MS, had been established. The conditions of detection were: carrier gas was helium, derivatives were separated with SE-54 fused silica capillary column, using temperature program and detected by using multiple ion detection mode in which the ion of m/z 432 was the monitoring ion. The method is rapid, sensitive and specific. For the ratio of testosterone to epi-testosterone (testosterone: 20 ng/microliters), there is a linearity between ratio 1:1 and 10:1 (r = 0.998), the limit of detection for testosterone and epi-testosterone is 1 ng, and the minimum concentration of detection in urine is 8 ng/ml.
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