Profiling steroid hormones and urinary steroids

Analysis of conjugated steroid androgens: deconjugation, derivatisation and associated issues

Gas chromatography/mass spectrometry (GC/MS) is the preferred technique for the detection of urinary steroid androgens for drug testing in athletics. Excreted in either the glucuronide or sulfated conjugated form, steroids must first undergo deconjugation followed by derivatisation to render them suitable for GC analysis. Discussed herein are the deconjugation and the derivatisation preparative options. The analytical challenges surrounding these preparatory approaches, in particular the inability to cleave the sulfate moiety have led to a focus on testing protocols that reply on glucuronide conjugates. Other approaches which alleviate the need for deconjugation and derivatisation are also highlighted.

Excretion of norsteroids' phase II metabolites of different origin in human

The urinary phase II metabolites of norsteroids, 19-norandrosterone, 19-noretiocholanolone and 19-norepiandrosterone glucuronide and sulphate, were analyzed in samples collected during the pregnancy, following the administration of norsteroids or the consumption of edible parts of non-castrated pig and in athletes' samples in which they were found during routine controls. The level of the sulfo- and glucuroconjugated metabolites was precisely determined by GC/HRMS, after selective hydrolysis. The goal was to evaluate whether the fine analysis of the norsteroid conjugates produced and excreted in different conditions would show a pattern that could be linked to their origin. The delta (13)C values of the metabolites formed following the ingestion of edible parts of non-castrated pig were measured by isotope ratio mass spectrometry. Our results indicated that it is not possible to determine the origin of the urinary metabolites based upon the sole evaluation of the different metabolites and conjugates. The GC/C/IRMS is the only method permitting to distinguish between the exogenous and endogenous origin of the metabolites.

The corticosteroid metabolic profile of the mouse

Data are presented on the urinary corticosteroid metabolic profile of the mouse strain 129/svJ. Through the use of GC/MS we have characterized, or tentatively identified corticosterone (Kendall's compound B) metabolites of both the 11beta-hydroxy and 11-carbonyl (compound A) series in urine. Full mass spectra of the methyloxime-trimethylether derivatives of 15 metabolites are included in the paper as an aid to other researchers in the field. Metabolites ranged in polarity from tetrahydrocorticosterone (THB) to dihydroxy-corticosterone with dominance of highly polar steroids. We found that prior to excretion corticosterone can undergo oxidation at position 11beta, reduction at position 20 and A-ring reduction. Metabolites retaining the 3-oxo-4-ene structure can be hydroxylated at position 6beta- as well as at an unidentified position, probably 16alpha-. Saturated steroids can be hydroxylated at positions 1beta-, 6alpha-, 15alpha- and 16alpha. A pair of hydroxy-20-dihydro-corticosterone metabolites (OH-DHB) were the most important excretory products accounting for about 40% of the total. One metabolite of this type was identified as 6beta-hydroxy-DHB; the other, of similar quantitative importance was probably 16alpha-hydroxy-DHB. The ratio of metabolites of corticosterone (B) to those of 11-dehydro-corticosterone (A) was greater than 9:1, considerably higher than that for the equivalent "human" ratio of 1:1 for cortisol to cortisone metabolites. Results from this study allowed the evaluation of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) activity in mice with deleted glucose-6-phosphate transporter (G6PT). These mice had attenuated back-conversion of A to B resulting in an increased ratio of A-metabolites to B-metabolites [Walker EA, Ahmed A, Lavery GG, Tomlinson JW, Kim SY, Cooper MS, Stewart PM, 11beta-Hydroxysteroid dehydrogenase type 1 regulation by intracellular glucose-6-phosphate, provides evidence for a novel link between glucose metabolism and HPA axis function. J Biol Chem 2007;282:27030-6]. We believe this study is currently the most comprehensive on the urinary steroid metabolic profile of the mouse. Quantitatively less steroid is excreted in urine than in feces by this species but urine analysis is more straightforward and the hepatic metabolites are less subject to microbial degradation than if feces was analyzed.

Simultaneous determination of tetrahydrocortisol, allotetrahydrocortisol and tetrahydrocortisone in human urine by liquid chromatography-electrospray ionization tandem mass spectrometry

Simultaneous quantification method of three major metabolites of cortisone and cortisol, tetrahydrocortisol, allotetrahydrocortisol and tetrahydrocortisone by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was investigated in a positive mode using a recently developed picolinyl derivatization. Conversion of each steroid into the corresponding picolinyl derivatives (1b, 2b or 3b) was performed by mixed anhydride method using picolinic acids and 2-methyl-6-nitrobenzoic anhydride. Derivatization proceeded smoothly to afford the corresponding 3, 21-dipicolinyl derivatives. Positive ion-ESI mass spectra of the picolinyl derivatives were dominated by an appearance of [M+H](+) as base peaks in all cases. The picolinyl derivatives provided 15 to 80-fold higher ESI response in the LC-ESI-MS/MS (selected reaction monitoring: SRM) when compared to those of underivatized molecules in a positive LC-ESI mode. The use of the picolinyl ester, solid-phase extraction, and deuterium labeled internal standards enabled the concentrations of these metabolites in human urine to be determined simultaneously by LC-ESI-MS/MS (SRM) with a small sample volume of less than 1microl urine.

Measuring urinary testosterone levels of the great apes--problems with enzymatic hydrolysis using Helix pomatia juice

Helix pomatia (Hp) juice is a common enzymatic preparation for deconjugation of urinary steroids. It has been used in many published studies on urinary testosterone (T) in chimpanzees and bonobos, although the ability of Hp juice to convert other urinary steroids into T has been reported for human urine. We developed a protocol for determination of reliable T levels in primate urine using liquid chromatography-mass spectrometry. T levels were determined in a set of human, bonobo and chimpanzee urine samples (A) by measurement of intact testosterone glucuronide (TG) and testosterone sulfate (TS), (B) after hydrolysis/solvolysis with beta-glucuronidase from Hp and (C) from Escherichia coli. When samples were hydrolyzed with Hp juice, results were not correlated with the direct assay of TG and TS, and determined T concentrations were considerably higher. By contrast, hydrolysis with E. coli beta-glucuronidase yielded a good agreement of T concentrations. We demonstrated the ability of Hp juice to convert androst-5-ene-3beta, 17beta-diol (A(5)diol) into T using commercial standards and within the urine of all three species. As A(5)diol usually is present at higher levels in urine than T, this artifact leads to erroneous results for T concentrations in primate urine. The proportion of T excreted as sulfate (TS) is often neglected as TS can only be cleaved by additional solvolysis. In all three species, we found substantial amounts of TS in the urine of some subjects and a high variance of TS proportion between and within subjects. Therefore the inclusion of solvolysis into the sample preparation seems necessary.

The application of carbon isotope ratio mass spectrometry to doping control

The administration of synthetic steroid copies is one of the most important issues facing sports. Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require methods of analysis that allow endogenous steroids to be distinguished from their synthetic analogs in urine. The ability to measure isotope distribution at natural abundance with high accuracy and precision has increased the application of Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS) to doping control in recent years. GC-C-IRMS is capable of measuring the carbon isotope ratio (delta(13)C) of urinary steroids and confirm their synthetic origin based on the abnormal (13)C content. This tutorial describes some of the complexities encountered by obtaining valid delta(13)C measurements from GC-C-IRMS and the need for careful interpretation of all relevant information concerning an individual's metabolism in order to make an informed decision with respect to a doping violation.

Factors influencing the steroid profile in doping control analysis

Steroid profiling is one of the most versatile and informative screening tools for the detection of steroid abuse in sports drug testing. Concentrations and ratios of various endogenously produced steroidal hormones, their precursors and metabolites including testosterone (T), epitestosterone (E), dihydrotestosterone (DHT), androsterone (And), etiocholanolone (Etio), dehydroepiandrosterone (DHEA), 5alpha-androstane-3alpha,17beta-diol (Adiol), and 5beta-androstane-3alpha,17beta-diol (Bdiol) as well as androstenedione, 6alpha-OH-androstenedione, 5beta-androstane-3alpha,17alpha-diol (17-epi-Bdiol), 5alpha-androstane-3alpha,17alpha-diol (17-epi-Adiol), 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo), 5alpha-androstanedione (Adion), and 5beta-androstanedione (Bdion) add up to a steroid profile that is highly sensitive to applications of endogenous as well as synthetic anabolic steroids, masking agents, and bacterial activity. Hence, the knowledge of factors that do influence the steroid profile pattern is a central aspect, and pharmaceutical (application of endogenous steroids and various pharmaceutical preparations), technical (hydrolysis, derivatization, matrix), and biological (bacterial activities, enzyme side activities) issues are reviewed.

Sodium ascorbate improves yield of urinary steroids during hydrolysis with Helix pomatia juice

Urinary steroid profile analysis requires enzymatic hydrolysis of glucuronide and sulfate conjugates and this is achieved simultaneously using Helix pomatia juice (HPJ), but steroids with 3beta-hydroxy-5-ene structure undergo transformation and yield of 5alpha-reduced corticosteroid glucuronides is poor. We describe the use of sodium ascorbate to solve these problems and provide a basis for its mode of action. Steroid conjugates were extracted from urine, hydrolyzed in acetate buffer with HPJ and sodium ascorbate and analyzed as methyloxime-trimethylsilylether derivatives by gas chromatography-mass spectrometry. Ranges of temperature, pH and ascorbate, substrate and HPJ concentrations were compared for urine and pure standards. Activity of other antioxidants and that of bacterial cholesterol oxidase were examined. Helix pomatia enzyme preparations from different commercial sources were compared. Loss of 3beta-hydroxy-5-ene steroids was enzyme-dependant, since it required HPJ, was saturable, subject to substrate competition and heat-inactivated. Products were 3-oxo-4-ene steroids and 4,6-diene and 6-oxy derivatives of these but the latter were not formed from 3-oxo-4-ene precursors. Ascorbate, other antioxidants or oxygen exclusion diminished activity. These characteristics were shared by cholesterol oxidase. Yield of 5alpha-reduced steroids was diminished by pre-incubation of HPJ before ascorbate addition and this was reversed if ascorbate was added to the pre-incubation mixture. We conclude that transformation of 3beta-hydroxy-5-ene steroids by HPJ is due to cholesterol oxidase and is diminished by antioxidants or oxygen denial. Yield of 5alpha-reduced steroids is low due to oxidative damage of beta-glucuronidase during hydrolysis, prevented by ascorbate. These features are shared by most commercial Helix pomatia enzyme preparations tested.

Assessment of three-dimensional sonographic features of polycystic ovaries after laparoscopic ovarian electrocautery

BACKGROUND

Treatment of polycystic ovary syndrome-related infertility includes laparoscopic ovarian electrocautery. Three-dimensional (3-D) sonographic characterization of polycystic ovaries has been performed recently, including the study of the effect of laparoscopic ovarian drilling on ovarian volume. The impact of laparoscopic treatment on ovarian volume and vascular flow-patterns assessed by 3-D color power angiography (CPA), however, has not yet been elucidated.

OBJECTIVE

To measure ovarian volume, to evaluate and quantify intraovarian blood flow with 3-D CPA histogram analysis before and after laparoscopic ovarian electrocautery, and to compare the hormonal effects of surgery with 3-D sonographic findings.

SETTING

University hospital.

PATIENT(S)

Ten patients, aged 18-34 years, with polycystic ovary syndrome.

INTERVENTION(S)

Evaluation of serum and urinary hormone profiles as well as transvaginal 3-D ultrasonography were performed before and after laparoscopic ovarian surgery.

RESULT(S)

Ovarian volume decreased, and 3-D CPA showed increased intraovarian flow intensity after laparoscopic electrocautery. Serum LH and T levels, ratios of urinary steroids reflecting 5 alpha-reductase enzyme activity, and androgen to cortisol metabolites decreased; serum FSH levels increased 1 week after laparoscopy and correlated well with changes of 3-D sonographic features. Seven patients ovulated regularly after surgery, and five pregnancies were conceived within 1 year.

CONCLUSION(S)

Three-dimensional ultrasonography may be a useful adjunct and noninvasive method for correlating clinical parameters with the blood flow alterations in polycystic ovary syndrome patients.

The analysis of estrone and 17β-estradiol by stir bar sorptive extraction–thermal desorption–gas chromatography/mass spectrometry: Application to urine samples after oral administration of conjugated equine estrogens

The development of a sensitive and solvent-free method for the measurement of estrone (E(1)) and 17beta-estradiol (17beta-E(2)) in human urine samples is described. The deconjugated estrogens were derivatized in situ with acetic acid anhydride and the derivatives were extracted directly from the aqueous samples using stir bar sorptive extraction (SBSE). The compounds containing a secondary alcohol function are further derivatized by headspace acylation prior to thermal desorption and gas chromatography/mass spectrometry (GC/MS). A number of experimental parameters, including salt addition, temperature and time, were optimized to increase the recovery of E(1) and 17beta-E(2) by SBSE. The derivatization reactions were also optimized to obtain the highest yields of the acylated estrogens. Detection limits of 0.02 and 0.03 ng mL(-1) were obtained for E(1) and 17beta-E(2), respectively. The method was applied to determine the effect of conjugated equine estrogen intake on the excretion of E(1) and 17beta-E(2) in human urine samples. Increased levels of the endogenous estrogens were detected after administering a standard dose of Premarin to a female volunteer. Routine monitoring of estrogen levels is recommended to avoid a high urinary excretion of E(1) and 17beta-E(2), nowadays enlisted as endocrine disrupting chemicals (EDCs), during hormone replacement therapy.

Synthesis and analytics of 2,2,3,4,4-d5-19-nor-5alpha-androsterone--an internal standard in doping analysis

A short and efficient synthesis of pentadeuterated 2,2,3,4,4-d5-19-nor-5alpha-androsterone 7 starting from 19-norandrost-4-ene-3,17-dione 1 by a d1-L-Selectride mediated stereo- and regioselective reduction of the 3-keto group is presented. The use of compound 7 as internal standard for the detection of anabolic steroids via mass spectrometric techniques such as gas chromatography-mass spectrometry (GC-MS) is discussed.

Methodology of the thyroid gland disease decision-making using profiling in steroid hormone pathway

To find out the genetic factors of outbreak of thyroid gland disease, we developed the thyroid gland decision-making system, which processes the metabolic profile in steroid hormone map using a statistical method. Metabolic profile is a measured data of lots of mixed materials that includes not only known metabolites, but also unknown ones, which is estimated to have an influence on the thyroid gland disease. Therefore, to develop thyroid gland disease decision-making system, analyzing metabolic profile containing multi-materials would be useful for diagnosing thyroid gland disease. Because experimental values used for system construction are area values for the retention time, the observations are preprocessed through variable transition and t-test to use the area values concurrently and the highly correlated materials are estimated by principal component analysis. The thyroid gland decision-making system developed through the logistic regression is an excellent system demonstrating 98.7% accuracy in the classification table.

Quantification of testosterone and epitestosterone in human urine samples by stir bar sorptive extraction – thermal desorption – gas chromatography/mass spectrometry: Application to HIV-positive urine samples

A simple method is described for the measurement of testosterone (T) and epitestosterone (ET) in human urine samples. The deconjugated steroids were extracted directly from the samples by stir bar sorptive extraction (SBSE) and derivatized in situ on the stir bar by headspace acylation prior to thermal desorption and GC/MS. Extraction and derivatization parameters, namely salt addition, temperature, and time, were optimized to improve the recovery of T and ET by SBSE. The limits of quantification (S/N 10) were 0.9 ng/mL for T and 2.8 ng/mL for ET. Quantification of the steroids in urine samples was performed using standard addition to avoid the influence of matrix effects. The method was applied for the measurement of urinary T and ET in a group of healthy volunteers and HIV+ patients. Decreased levels of T were detected in the HIV+ group, whereas the excretion of ET was comparable for the two groups. Further clinical research is required to elucidate the biomarker significance of the T/ET ratio in HIV infection.

High-throughput urine screening for Smith-Lemli-Opitz syndrome and cerebrotendinous xanthomatosis using negative electrospray tandem mass spectrometry

BACKGROUND

Smith-Lemli-Opitz syndrome (SLOS) and cerebrotendinous xanthomatosis (CTX) are disorders affecting cholesterol metabolism. Currently, diagnosis relies on clinical recognition and specific and complex biochemical testing.

METHODS

A rapid, high-throughput urine test, suitable for mass screening for these two disorders, was developed using flow injection negative electrospray tandem mass spectrometry with multiple reaction monitoring. Cholestane-pentol glucuronide, a known marker for CTX, was measured and a steroid sulfate with a proposed keto-pregnadien-diol structure was identified and measured for SLOS. Measurement of the two markers was readily incorporated into an existing tandem mass spectrometry method for diagnosing inborn errors of amino and organic acid metabolism.

RESULTS

Levels in affected patients were well separated from 1738 controls, ranging from 6.7 to 100 times the 99.7th percentile of controls in SLOS patients (n=3) and 7.3 to 24 times the 99.7th percentile of controls in CTX patients (n=4).

CONCLUSIONS

The addition of testing for SLOS and CTX to a routine tandem mass spectrometry urine screening program simplifies the diagnosis of these two disorders and further extends the range of inborn errors of metabolism detected by this technique.

Monitoring testicular activity of male Eurasian (Lynx lynx) and Iberian (Lynx pardinus) lynx by fecal testosterone metabolite measurement

The aim of the present study was to identify relevant fecal testosterone metabolites in the Eurasian lynx (Lynx lynx) using HPLC analysis and to evaluate the specificity of two testosterone immunoassays against these fecal metabolites. Finally, fecal hormone analysis was used to characterize seasonal reproductive activity of captive male Eurasian and Iberian (Lynx pardinus) lynx. Fecal samples from a male Eurasian lynx who received an i.v. injection of [3H]testosterone were subjected to HPLC analysis. All HPLC fractions were analyzed for radioactivity and androgen content by two testosterone immune assays (EIA and Testosterone-Immulite kits, DPC Biermann, Germany). Furthermore, fecal samples from four Eurasian lynx males (n=174) and three Iberian lynx (n=52) were collected throughout the year and fecal testosterone metabolites were determined with Testosterone-Immulite assay. HPLC separation of radiolabeled Eurasian lynx fecal extract indicated that the majority of testosterone metabolites are substances with a higher polarity than testosterone. Only minor proportion of radioactivity co-eluted with authentic testosterone and dihydrotestosterone. Enzymatic hydrolysis and solvolysis of the fecal extract were insufficient to liberate testosterone. After solvolysis relatively more activity was eluated the position of DHT, but the majority of metabolites remained unaffected. The EIA measured substantial amount of immunoreactivity, which corresponded with two radioactive peaks. Additionally, both immunoassays recognized two metabolites, which were only minor components according to their radioactivity. The Immulite assay was able to recognize a metabolite at the position of dihydrotestosterone. HPLC separation of Iberian lynx feces extracts revealed a similar metabolite pattern determined by EIA that were typical for Eurasian lynx fecal extracts. Simultaneous analyses of fecal samples with both testosterone assays provided comparative results for both lynx species (Eurasian lynx, r2=0.488; p<0.001; Iberian lynx, r2=0.85, p<0.0001). Thus, seasonal reproductive activity of male Eurasian lynx was demonstrated also by Immulite -assay, confirming high testosterone levels during breeding season in March/April as previously documented with EIA. Preliminary results on testosterone measurements in Iberian lynx feces confirmed the suitability of the applied Immulite test in this highly endangered species.

Comparison of vitellogenin induction, sex ratio, and gonad morphology between zebrafish and Japanese medaka after exposure to 17alpha-ethinylestradiol and 17beta-trenbolone

The pharmaceutical estrogen 17alpha-ethinylestradiol (EE2) and the anabolic androgen 17beta-trenbolone (Tb) can interfere with the endocrine and reproductive systems of fish. The potency of these chemicals in zebrafish (Danio rerio) and Japanese medaka (Oryzias latipes) was assessed using the core end points vitellogenin (Vtg) concentration at 38 days post-hatch and sex ratio and gonad morphology at 60 days post-hatch. Vtg concentrations were measured in fish whole-body homogenate samples using enzyme-linked immunosorbent assay. Increased Vtg concentration and feminization of fish after exposure to 10 ng/L EE2, as well as masculinization after exposure to 50 ng/L of Tb, were observed in zebrafish. Intersex was observed in medaka exposed to EE2. A decrease in Vtg production after Tb exposure (50 ng/L) was measured in both zebrafish and medaka. Analyses of gonad morphology revealed increased testicular area and sperm percentage in Tb-exposed zebrafish, whereas increased sperm percentage was measured in Tb-exposed medaka. The higher sensitivity of zebrafish compared with medaka to both EE2 and Tb was revealed in the study.

Determination of free tetrahydrocortisol and tetrahydrocortisone ratio in urine by liquid chromatography-tandem mass spectrometry

OBJECTIVE

Measurement of urinary free tetrahydrocortisol and tetrahydrocortisone ratio (allo-THF+THF)/THE is clinically important in the diagnosis of hypertension caused by congenital absence of 11beta-hydroxysteroid dehydrogenase type 2 (apparent mineralocorticoid excess, AME) or inhibition of the enzyme after licorice ingestion. Although gas chromatography-mass spectrometry (GC-MS) provides reliable results, it requires derivatization and is lengthy and time-consuming. The purpose of this study was to demonstrate that detection by liquid chromatography-mass spectrometry (LC-MS) is a potentially superior method.

MATERIAL AND METHODS

The analysis utilizes 1 mL urine. The samples were extracted with solid-phase extraction (SPE) using ethyl acetate as eluent. The extract was evaporated to dryness, and allo-tetrahydrocortisol (allo-THF), THF and THE concentrations were analyzed by LC-MS/MS operating in the negative mode after separation on a reversed-phase column. The calibration curves exhibited consistent linearity and reproducibility in the range of 7.5-120 nmol/L. Interassay CVs were 7.0-10 % at mean ratios of (allo-THF+THF)/THE of 0.54-1.9. The detection limit of the analytes was 0.4-0.8 nmol/L (signal-to-noise ratio = 3). The mean recovery of the three analytes ranged from 88 to 95 %. The regression equation for the free ratio using the LC-MS/MS (x) method and the total ratio using the GC-MS (y) method was: y = 0.30x+0.91 (r = 0.61; n = 25).

CONCLUSIONS

The sensitivity and specificity of the LC-MS/MS method offer an advantage over GC-MS by eliminating derivatization. The high costs of equipment are balanced by higher through-put, owing also to shorter chromatographic run times.

Urinary sex steroid excretion levels during a soy intervention among young girls: a pilot study

Soy intake early in life may protect against breast cancer later in life, possibly by altering sex hormone metabolism. We evaluated the feasibility of assessing urinary sex steroid excretion among 20 young girls aged 8-14 yr in an 8-wk trial. The girls consumed one daily soy serving, collected weekly overnight urine samples, and reported Tanner stages for breast and pubic hair development. Sex steroid excretion was measured in duplicate by gas chromatography-mass spectrometry and adjusted for urinary creatinine. The respective coefficients of variation for estrone, estradiol, estriol, testosterone, pregnanediol were 11.4%, 10.4%, 8.4%, 12.8%, and 4.6%. The statistical analysis included t-tests, Spearman's correlations, and analysis of variance. Seventeen girls completed the study and showed good compliance with the intervention strategy. We observed nonsignificant increases in total androgens (0.11 microg/mg creatinine) and total estrogens (0.001 microg/mg creatinine) and a nonsignificant decrease in pregnanediol (-0.03 microg/mg creatinine) during the study period. Higher Tanner stages for pubic hair development were associated with ninefold higher estrogen, fourfold higher androgen, and twofold higher pregnanediol excretions (P=0.01, P<0.001, and P=0.047, respectively). Similar differences were observed after stratification by breast development and menarcheal status. The association of sex steroid levels with pubertal development supports the validity of the sex steroid measurements.

The expanding role of mass spectrometry in metabolite profiling and characterization

Mass spectrometry has a strong history in drug-metabolite analysis and has recently emerged as the foremost technology in endogenous metabolite research. The advantages of mass spectrometry include a wide dynamic range, the ability to observe a diverse number of molecular species, and reproducible quantitative analysis. These attributes are important in addressing the issue of metabolite profiling, as the dynamic range easily exceeds nine orders of magnitude in biofluids, and the diversity of species ranges from simple amino acids to lipids to complex carbohydrates. The goals of the application of mass spectrometry range from basic biochemistry to clinical biomarker discovery with challenges in generating a comprehensive profile, data analysis, and structurally characterizing physiologically important metabolites. The precedent for this work has already been set in neonatal screening, as blood samples from millions of neonates are tested routinely by mass spectrometry as a diagnostic tool for inborn errors of metabolism. In this review, we will discuss the background from which contemporary metabolite research emerged, the techniques involved in this exciting area, and the current and future applications of this field.

Noninvasive Measures of Reproductive Function and Disturbance in the Barred Owl, Great Horned Owl, and Northern Spotted Owl

There is an urgent need for noninvasive methods to study reproduction and environmental stress in at-risk species such as the northern spotted owl (Strix occidentalis caurina). Two related owl species (barred owl and great horned owl) were used as surrogates to validate hormone assays for fecal metabolites of progesterone, 17beta-estradiol, testosterone, and corticosterone. Infusions of radiolabeled hormones showed that the owls excreted most hormone within 6 h. Feces and urine contained roughly equal amounts of hormone, and most fecal hormone metabolites were quite polar. The testosterone and corticosterone assays in this study bound to the major excreted metabolites of these hormones, but two progesterone assays did not appreciably bind to the major progesterone metabolites. All assays showed excellent parallelism with hydrolyzed and unhydrolyzed samples and with previously dried or undried fecal samples. Thus, samples do not require hydrolysis or prior drying. Samples from a female barred owl had significantly higher fecal estrogen, lower fecal testosterone, and higher fecal estrogen/testosterone ratio than samples from two male barred owls. The fecal estrogen/testosterone ratio was the most accurate predictor of owl gender, particularly if two or more samples are available from the same individual. Fecal corticosterone metabolites also demonstrated considerable utility for wild northern spotted owls. Fecal glucocorticoid levels varied by gender and breeding stage, being highest in male northern spotted owls early in the breeding season and highest in females when nestlings were fledging. Collectively, these studies show that noninvasive fecal hormone measurements show great promise for noninvasive assessment of reproduction and stress in wild owls.

Direct determination of the ratio of tetrahydrocortisol+allo-tetrahydrocortisol to tetrahydrocortisone in urine by LC–MS–MS

The 11beta-hydroxysteroid dehydrogenase (11beta-HSD) is responsible for the interconversion of both the hormonally inactive cortisone and the active cortisol. This enzyme activity, which has implications in the pathogenesis of numerous diseases, is reflected in the ratio of tetrahydrometabolites of cortisol (allo-tetrahydrocortisol and tetrahydrocortisol) to those of cortisone (tetrahydrocortisone). Several methods have been proposed in the literature to determine such a ratio in urine. Most of them require tedious and extensive extraction and derivatization steps and make use of gas-chromatographic techniques, including gas chromatography coupled to mass spectrometry (GC-MS). We present here an alternative approach for the direct determination of such a ratio in urine by using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS), based on a minimal sample treatment. Actually, the limit of detections (LODs) for pure standards in water permitted a simple dilution of the urine samples prior to the analysis, hence, an accurate optimization of the high performance liquid chromatography (HPLC) separation was needed in order to get rid of the severe influence of the urine matrix on the ionization efficiency. Besides, the nature of some interfering species was deeply investigated, as well as the suitability of some commercial deuterated steroids as internal standards. All these led to the final method, which was based on a HPLC separation on a C8 column and a ternary gradient water/methanol/acetonitrile. In parallel, an appropriate sample preparation was set up, which consisted of an enzymatic hydrolysis of the conjugated species and a followed 1:20 dilution. Preliminary measurements on real urine samples were performed as well.

Application of stable carbon isotope analysis to the detection of 17β-estradiol administration to cattle

The use of anabolic agents in food producing animals is prohibited within the EU since 1988 (96/22/EC directive). The control of the illegal use of natural steroid hormones in cattle is still an exciting analytical challenge as far as no definitive method and non-ambiguous analytical criteria are available. The ability of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to demonstrate the administration of 17beta-estradiol to bovine has been investigated in this paper. By comparison of 13C/12C isotopic ratio of main urinary estradiol metabolite, i.e. 17alpha-estradiol, with two endogenous reference compounds (ERCs), i.e. dehydroepiandrosterone (DHEA) and 5-androstene-3beta,17alpha-diol, the differentiation of estradiol metabolite origin, either endogenous or exogenous, has been proved to be achievable. After treatment, the delta(13)C(VPDB)-values of 17alpha-estradiol reached -27 per thousand to -29 per thousand, whereas delta13CVPDB-values of DHEA remained between -13 per thousand and -20 per thousand depending on the diet, maize and grass, respectively. A significant difference of delta13CVPDB between ERCs and 17alpha-estradiol was measurable over a period of 2 weeks after estradiol ester administration to the animal.

Determination of urinary steroid sulfate metabolites using ion paired extraction

The need for laboratories accredited by the World Anti-Doping Agency (WADA) to develop methods of analysis for steroids excreted primarily as their sulfate conjugates has faced significant analytical challenges. One of the issues relates to the extraction of these metabolites from urine in a relatively pure state. The use of (-)-N,N-dimethylephedrinium bromide as an ion pairing reagent was optimised to produce a method that is selective for the extraction of steroid sulfates prior to GC-MS or LC-MS analysis, with minimal contributions from the urine matrix. The recovery of androsterone from its sulfate conjugate was determined to be 67% with a relative quantitative uncertainty of +/-14% (k = 2).

Delayed diagnosis of congenital adrenal hyperplasia with salt wasting due to type II 3beta-hydroxysteroid dehydrogenase deficiency

Classical 3beta-hydroxysteroid dehydrogenase (3beta-HSD) deficiency is a rare cause of congenital adrenal hyperplasia. We report two sisters presenting with delayed diagnoses of classical 3beta-HSD, despite salt wasting (SW) episodes in infancy. Sibling 1 was referred for premature pubarche, slight growth acceleration, and advanced bone age, whereas sibling 2 had no signs of virilization. At referral, increased 17alpha-hydroxyprogesterone associated with premature pubarche at first suggested a nonclassical 21-hydroxylase deficiency. Sequencing of the CYP21 gene showed both girls only heterozygotes (V281L mutation). This result, combined with SW in infancy, suggested a 3beta-HSD deficiency because of increased dehydroepiandrosterone sulfate levels. Further hormonal studies showed markedly elevated Delta5-steroids, in particular 17alpha-hydroxypregnenolone greater than 100 nmol/liter (the clue to the diagnosis) and elevated Delta5-/Delta4-steroid ratios. Sequencing of the type II 3beta-HSD gene documented that both girls were compound heterozygotes for T181I and 1105delA mutations. Retrospectively, elevated levels of 17alpha-hydroxyprogesterone were found on blood spots from Guthrie's test. There is no previous report of the combination of SW and premature pubarche due to mutations in the type II 3beta-HSD gene. Because neonatal diagnosis could have prevented life-threatening crises in these girls, this report further supports the benefits for neonatal screening for congenital adrenal hyperplasia whatever the etiology.

Pitfalls in trimethylsilylation of anabolic steroids

Mixtures such as N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA), ammonium iodide and dithioerythreitol (DTE) or MSTFA, trimethyliodosilane and DTE were used for derivatisation of anabolic steroids extracted from 2 g kidney fat and present at ng kg(-1) level. They are leading to unexpected products. Their identity and mechanism of formation have been discussed. A new silylation mixture was developed to overcome these pitfalls: N,O-bis-trimethylsilyl-acetamide was used in combination of 2.5% of MSTFA/I(2) (1000:10 (v/w)). A single product consisting in ether-TMS and/or enol-TMS derivative was observed for all tested steroids with a stability demonstrated for at least 48 h. Quantitative application was proved even at the low ng kg(-1) level in a complex biological matrices, i.e. kidney fat.

Searching for new markers of endogenous steroid administration in athletes: “looking outside the metabolic box”

A simple means of detecting the abuse of steroids that also occur naturally is a problem facing doping control laboratories. Specific markers are required to allow the detection of the administration of these steroids. These markers are commonly measured using a set of data obtained from the screening of samples by gas chromatography-mass spectrometry (GC-MS). Doping control laboratories further need to confirm identified abuse using techniques such as gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). An interesting urinary species was found while following the pharmacokinetics and changes to the steroid profile from single and multiple oral doses of the International Olympic Committee/World Anti Doping Agency (IOC/WADA) prohibited substance, dehydroepiandrosterone (DHEA). The urine samples collected from the administration studies were subject to GC-MS and GC-C-IRMS steroid analysis following cleanup by solid phase extraction techniques. A useful urinary product of DHEA administration was detected in the urine samples from each of the administration studies and was identified by GC-MS experiments to be 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo). This compound occurs naturally but the concentrations of 3alpha,5-cyclo were elevated following both the single DHEA administration (up to 385 ng/mL) and multiple DHEA administrations (up to 1240 ng/mL), in relation to those observed prior to these administrations (70 and 80 ng/mL, respectively). A reference distribution of urine samples collected from elite athletes (n = 632) enabled the natural concentration range of 3alpha,5-cyclo to be established (0-280 ng/mL), with a mean concentration of 22 ng/mL. Based on this an upper 3alpha,5-cyclo concentration limit of 140 ng/mL is proposed as a GC-MS screening marker of DHEA abuse in athletes. GC-C-IRMS analysis revealed significant 13C depletion of 3alpha,5-cyclo following DHEA administration. In the single administration study, the delta13C value of 3alpha,5-cyclo changed from -24.3 per thousand to a minimum value of -31.1 per thousand at 9 h post-administration, before returning to its original value after 48 h. The multiple administration study had a minimum delta13C 3alpha,5-cyclo of -33.9 per thousand during the administration phase in contrast to the initial value of -24.2 per thousand. Preliminary studies have shown 3alpha,5-cyclo to most likely be produced from DHEA sulfate found at high levels in urine. The complementary use of GC-MS and GC-C-IRMS to identify new markers of steroid abuse and the application of screening criteria incorporating such markers could also be adapted by doping control laboratories to detect metabolites of androstenedione, testosterone and dihydrotestosterone abuse.

Glucocorticoids contribute to the heritability of leptin in Scottish adult female twins

OBJECTIVE

The precise interactions between glucocorticoids and leptin are complex and poorly understood. The aim of the study was to investigate whether the glucocorticoid/leptin interaction is influenced by shared environmental or genetic factors.

DESIGN

We investigated the heritability of body mass index (BMI), circulating leptin and urinary glucocorticoid metabolites [tetrahydrocortisol (THF), alloTHF and tetrahydrocortisone (THE)] in 54 monozygotic (MZ) and 39 dizygotic (DZ) female twins. Analysis was performed using a structural equation modelling package Mx, developed by Neale.

RESULTS

Leptin and BMI showed substantial heritability (68.3% and 71.3%, respectively). Bivariate analysis indicated that the genetic determinants of BMI and leptin are partly shared. Total cortisol metabolites (THF + alloTHF + THE), the (THE + alloTHF)/THE ratio [a marker of 11beta-hydroxysteroid dehydrogenase (11HSD) activity] and the alloTHF/THF ratio (marker for 5alpha-reductase activity) followed an environmental pattern. The heritability of leptin was significantly lowered to 63.8% (P = 0.012) when values were corrected for the influence of total cortisol metabolites but unaffected by markers of 11HSD and 5alpha-reductase activity.

CONCLUSIONS

We confirm that the genetic influence on both BMI and the circulating leptin concentration is substantial and show that these genetic determinants are highly correlated. These genetic factors, which are more likely to be dominant than additive, can be modestly but significantly modified by urinary total cortisol metabolites implying an adrenal influence.

Complex glycerol kinase deficiency leads to psychomotor and body-growth failure

Complex glycerol kinase deficiency usually presents with Duchenne muscular dystrophy, glycerol kinase deficiency and adrenal hypoplasia congenital. We describe a follow-up patient with complex glycerol kinase deficiency who had appropriate intrauterine development, but who at 1 month of age manifested severe growth delay and psychomotor retardation. Targeted therapy did not bring about the regression of symptoms: both bodyweight and height were below the 3rd centile until 8 years of age, and his Griffith's Mental Development scale score was 71 at age 5 years.

Mutation analysis of CYP11B1 and CYP11B2 in patients with increased 18-hydroxycortisol production

BACKGROUND

In patients with glucocorticoid remediable aldosteronism (GRA), a rare hypertensive disorder caused by the presence of a chimeric aldosterone synthase (CYP11B2) and 11beta-hydroxylase (CYP11B1) gene, high level of urinary 18-hydroxycortisol (18OHF) excretion are observed. In some patients with hypertension, increased urinary 18OHF secretion is also found in the absence of the hybrid CYP11B1/CYP11B2 gene. We hypothesised that gene variants of CYP11B1 or CYP11B2 may be linked to this abnormal glucocorticoid production.

METHODS

The urinary steroid profile was analysed by gas chromatography/mass spectrometry in 429 hypertensive patients and 98 (23%) thereof tested positive for increased 18OHF excretion. After correction for total cortisol excretion, 12 subjects showed an abnormally high 18OHF excretion. For genotyping DNA was obtained from six of these patients. All were tested negative for the hybrid CYP11B1/CYP11B2 gene and were further analysed for mutations in all exons and promoter regions of both CYP11B1 and CYP11B2 by single strand conformation polymorphism (SSCP) and sequencing when appropriate.

RESULTS

The genetic analysis of the two genes revealed the presence of nine molecular variants in CYP11B2 and three in CYP11B1. In addition to published polymorphic sites, we identified two new variants in CYP11B2 but no new variants in CYP11B1. The newly identified CYP11B2 mutations are a C/T single nucleotide exchange located in the first intron and a double nucleotide exchange at the 3'-splice site of exon 8. The mutated sequence corresponds to the sequence of CYP11B1 indicating a gene conversion. This suggests that the mutant is not likely to affect splicing. Thus, none of the genetic variants identified explains the high urinary excretion of 18OHF.

CONCLUSIONS

We present here a complete method for the genetic analysis of the CYP11B1 and CYP11B2 genes. By this method we could not identify genetic variants responsible for a GRA-like phenotype. The presence of high levels of 18OHF should not be used alone as a diagnosis tool for GRA.

Epitestosterone

Epitestosterone has been identified as a natural component of biological fluids of several mammals including man. For a long time it was believed that it is a metabolite without any hormonal activity and without any marked relationship to the hormonal state in health and disease. Neither the biosynthetic pathway nor the site of its formation in man have been unequivocally confirmed to date. It apparently parallels the formation of testosterone (T), but on the other hand its concentration is not influenced by exogenous administration of testosterone. This fact creates the basis of the present doping control of testosterone abuse. In 1989 an observation was presented in a dermatological study that epitestosterone exerts an effect counteracting the action of testosterone on flank organ of Syrian hamster. Further studies showed that a complex action consisting of competitive binding of epitestosterone to androgen receptor, of inhibition of testosterone biosynthesis and its reduction to dihydrotestosterone and of antigonadotropic activity could be demonstrated in rat, mice and human tissues. It can be presumed that epitestosterone as a natural hormone can contribute to the regulation of such androgen dependent events as, e.g. the control of prostate growth or body hair distribution.

Controle de dopagem de anabolizantes: o perfil esteroidal e suas regulações

O conceito de perfil esteroidal é discutido neste artigo. As principais vias biossintéticas são apresentadas. A importância do monitoramento do perfil esteroidal é demonstrada dentro da clínica médica e da medicina esportiva. Parâmetros da literatura para a identificação de dopagem por esteróides endógenos são apresentados, assim como os fatores que acarretam alterações no perfil esteroidal normal. É dada atenção especial a essa última abordagem.

A facile and high yielding synthesis of 2,2,3,4,4-d5-androsterone-beta-D-glucuronide--an internal standard in dope

A facile six-step synthesis of 2,2,3,4,4-d5-androsterone-beta-D-glucuronide (1) starting from epiandrosterone (2) in 63% yield is described and compared with several alternative synthetic pathways. Compound 1 can be used as an internal standard in screening procedures for anabolic steroids to monitor the hydrolysis step of the steroid glucuronides prior to gas chromatography-mass spectrometry (GC-MS) analysis. Thus, a time consuming solid-phase extraction step to remove possible hydrolysis inhibitors can be omitted.

Identification of 7(8) and 8(9) unsaturated adrenal steroid metabolites produced by patients with 7-dehydrosterol-delta7-reductase deficiency (Smith-Lemli-Opitz syndrome)

Patients with Smith-Lemli-Opitz syndrome have impaired ability to synthesize cholesterol due to attenuated activity of 7-dehydrosterol-delta(7)-reductase which catalyses the final step in cholesterol synthesis. Accumulation of 7- and 8-dehydrocholesterol is a result of the disorder and potentially these sterols could be used as precursors of a novel class of delta(7) and delta(8) unsaturated adrenal steroids and their metabolites. In this study, we have analyzed urine from SLOS patients in the anticipation of characterizing such metabolites. Gas chromatography/mass spectrometry (GC/MS) was used in the identification of two major metabolites as 7- and 8-dehydroversions of the well-known steroid pregnanetriol. Other steroids, such as 8-dehydro dehydroepiandrosterone (8-dehydro DHEA) and 7- or 8-dehydroandrostenediol were also identified, and several more steroids are present in urine but remain uncharacterized. As yet, the study provides no evidence for the production of ring-B unsaturated metabolites of complex steroids, such as cortisol. We believe that the following transformations can utilize ring-B dehydroprecursors: StAR transport of cholesterol, p450 side chain cleavage, 17-hydroxylase/17,20-lyase, 3beta-hydroxysteroid dehydrogenase, 3alpha-hydroxysteroid dehydrogenase, 17beta-hydroxysteroid dehydrogenase, 20alpha-hydroxysteroid dehydrogenase and 5beta-reductase. We have yet to prove the activity of adrenal 21-hydroxylase, 11beta-hydroxylase or 5alpha-reductase towards 7- or 8-dehydroprecursors.

Measurement of corticoids in the patients with clinical features indicative of mineralocorticoid excess

BACKGROUND

A method for the measurement of five important serum and urinary corticoids on the syndrome of mineralcorticoid excess is reported. The methodology was combined gas chromatography-mass spectrometry (GC-MS) with selected ion-monitoring mode.

METHODS

After extraction with a solid-phase cartridge using an Oasis HLB copolymer, the residues were derivatized with a mixture of N-methyl-N-trimethylsilyltrifluoroacetamide/ammonium iodide/dithioerythritol (1000:4:5, v/w/w), and analyzed.

RESULTS

The linearity as the regression coefficients were >0.979 over a range of 1-500 ng/ml, and limit of detection ranged from 1 to 3 ng/ml while their analytical recoveries varied in the range of 75.7-94.9%. The overall precision (% CV) of the method were 3.2-7.2% and 3.6-6.3% for serum and urine, respectively. The accuracy expresses as % bias ranged from -4.1 to 6.4%. This assay was used on two patients with hypokalemic hypertension, and may be useful in ruling out mineralcorticoid excess (AME) type 1 or 2.

CONCLUSIONS

The present GC-MS technique may be useful to differentiate between the syndrome of AME and other hypertensive diseases with clinical features suggestive of mineralcorticoid excess because of the assay's reliablity and precision.

Separation and detection of neuroactive steroids from biological matrices

This review is based on a selection of research papers published mainly in the last decade and it describes various analytical aspects of separation and detection of neuroactive steroids in biological matrices.

Increased cortisol metabolites and reduced activity of 11beta-hydroxysteroid dehydrogenase in patients on hemodialysis

BACKGROUND

Patients with renal failure have symptoms assumed to be attributable to the accumulation of toxic endo- or xenobiotics. Most of these molecules, especially those with a molecular weight>300 D, have not been identified. In addition to excretion, the kidney is involved in some defined metabolic processes. In the cortical collecting duct, the enzyme 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) interconverts cortisol (F) and cortisone (E), and the metabolites of these glucocorticoids, tetrahydrocortisol (THF), 5alpha-tetrahydrocortisol (5alpha-THF) and tetrahydrocortisone (THE), are excreted in urine. We hypothesized that first, these metabolites accumulate and second, their concentration pattern changes in patients on hemodialysis.

METHODS

THF, 5alpha-THF, THE, F and E were measured in plasma of 63 patients on dialysis and in 34 healthy controls by gas-chromatography-mass spectrometry (GC/MS). In 11 patients, the metabolite clearance was determined during high flux hemodialysis by using a population pharmacokinetic approach.

RESULTS

Mean plasma concentrations of THF, 5alpha-THF and THE were more than five times higher and those of E lower in patients than in controls. The ratios of (THF + 5alpha-THF)/THE and F/E were increased in patients, indicating a reduced activity of 11beta-HSD2. Intradialytic clearances were between 120 and 300 mL/min and not sufficient to normalize the steroid concentrations.

CONCLUSION

Patients on hemodialysis exhibit pronounced increases in THF, 5alpha-THF and THE concentrations in plasma with insufficient removal during dialysis. Due to a reduced 11beta-HSD2 activity, an abnormal pattern of the concentrations of these cortisol and cortisone metabolites is observed. Since many signs and symptoms in uremic patients resemble those observed in subjects with glucocorticoid excess, the clinical relevance of the high concentrations of these glucocorticoid metabolites deserves further investigation.

In vivo 11beta-HSD-2 activity: variability, salt-sensitivity, and effect of licorice

Loss-of-function mutations or inhibition of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD-2) results in overstimulation of the mineralocorticoid receptor by cortisol and causes salt-sensitive hypertension. Traditionally, 11beta-HSD-2 activity has been assessed by measurement of the urinary cortisol metabolite ratio (tetrahydrocortisol [THF]+5alpha-THF)/tetrahydrocortisone (THE). Recently, the ratio of urinary free glucocorticoids, UFF/UFE, has been suggested to be a more reliable parameter, an aspect that has not been investigated systematically. Steroid metabolites were measured repeatedly by gas chromatography-mass spectrometry in 20 healthy subjects at baseline and after 1 week each of a 30- or 180-mmol/d of sodium diet or 500 mg/d of glycyrrhetinic acid. Intraindividual coefficients of variation from 3 random urine collections for (THF+5alpha-THF)/THE and UFF/UFE ratios were 11+/-9% and 25+/-14% (P<0.001). (THF+5alpha-THF)/THE was more sensitive than UFF/UFE for detection of glycyrrhetinic acid-induced increases higher than the upper 95% confidence interval of the coefficient of variation of the corresponding ratio. Low- or high-salt diet did not alter either ratio. Mean (THF+5alpha-THF)/THE but not UFF/UFE was higher in salt-sensitive than salt-resistant subjects. Absolute glycyrrhetinic acid-related increase in (THF+5alpha-THF)/THE but not UFF/UFE was higher in salt-sensitive than salt-resistant subjects and correlated with changes in mean BP. Intraindividual variability of (THF+5alpha-THF)/THE is lower than that of UFF/UFE. The UFF/UFE ratio does not appear to be more sensitive than (THF+5alpha-THF)/THE for detection of decreased 11beta-HSD-2 activity. The (THF+5alpha-THF)/THE ratio better discriminates between salt-sensitive and salt-resistant subjects. Together with BP responses to glycyrrhetinic acid, these findings support a pivotal role of 11beta-HSD-2 in salt sensitivity.

High-performance liquid chromatographic analysis of dehydroepiandrosterone

Qualitative and quantitative analysis of dehydroepiandrosterone and its conjugates in biological matrices and establishment of their relationships with physiological functions is a very active field. This review article discusses methods of separation and quantification of dehydroepiandrosterone and its conjugates using high-performance liquid chromatographic techniques.

Reduced activity of 11 beta-hydroxysteroid dehydrogenase in patients with cholestasis

Enhanced renal sodium retention and potassium loss in patients with cirrhosis is due to activation of mineralocorticoid receptors (MRs). Increased aldosterone concentrations, however, do not entirely explain the activation of MR in cirrhosis. Here, we hypothesize that cortisol activates MRs in patients with cholestasis. We present evidence that access of cortisol to MRs is a result of bile acid-mediated inhibition of 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta-HSD2), an MR-protecting enzyme that converts cortisol to cortisone. Twelve patients with biliary obstruction and high plasma bile acid levels were studied before and after removal of the obstruction. The urinary ratio of (tetrahydrocortisol + 5 alpha-tetrahydrocortisol)/tetrahydrocortisone, a measure of 11 beta-HSD2 activity, decreased from a median of 1.91 during biliary obstruction to 0.78 at 4 and 8 weeks after removal of the obstruction and normalization of plasma bile acid concentrations. In order to demonstrate that bile acids facilitate access of cortisol to the MR by inhibiting 11 beta-HSD2, an MR translocation assay was performed in HEK-293 cells transfected with human 11 beta-HSD2 and tagged MR. Increasing concentrations of chenodeoxycholic acid led to cortisol-induced nuclear translocation of MR. In conclusion, 11 beta-HSD2 activity is reduced in cholestasis, which results in MR activation by cortisol.

Hydrolysis of conjugated steroids by the combined use of beta-glucuronidase preparations from helix pomatia and ampullaria: determination of urinary cortisol and its metabolites

This study describes the enzymatic hydrolysis of urinary conjugates of cortisol, cortisone, tetrahydrocortisol, allotetrahydrocortisol, and tetrahydrocortisone with beta-glucuronidase preparations from Helix pomatia and Ampullaria. The objective of the present studies was to find optimal hydrolysis conditions for these conjugated steroids. Assay of the isolated steroids was carried out by GC-MS using deuterium-labeled compounds as internal standards. The allotetrahydrocortisol conjugate was clearly the hardest to hydrolyze with enzyme from Helix pomatia and required increased enzyme concentration and prolonged incubation. Hydrolysis of a urine sample for 2.0 h with the simultaneous use of 3400 units/ml Ampullaria and 5400 units/ml Helix pomatia enzymes in 0.5 M acetate buffer at 55 degrees C achieved more complete cleavage of the urinary conjugates of the five steroids examined. It is thus advantageous to use the Ampullaria and Helix pomatia enzymes in combination to obtain the highest yield in the urinary corticosteroid assay.

Sampling and analysis of airborne particulate matter and aerosols using in-needle trap and SPME fiber devices

A needle trap device (NTD) and commercial poly(dimethylsiloxane) (PDMS) 7-microm film thickness solid-phase microextraction (SPME) fibers were used for the sampling and analysis of aerosols and airborne particulate matter (PM) from an inhaler-administered drug, spray insect repellant, and tailpipe diesel exhaust. The NTD consisted of a 0.53-mm o.d. stainless steel needle having 5 mm of quartz wool packing section near the needle tip. Samples were collected by drawing air across the NTD with a Luertip syringe or via direct exposure of the SPME fiber. The mass loading of PM was varied by adjusting the volume of air pulled through the NTD or by varying the sampling time for the SPME fiber. The air volumes ranged from 0.1 to 50 mL, and sampling times varied from 10 s to 16 min. Particulates were either trapped on the needle packing or sorbed onto the SPME fiber. The devices were introduced to a chromatograph/mass spectrometer (GC/MS) injector for 5 min desorption. In the case of the NTD, 10 microL of clean air was delivered by a gas-tight syringe to aid the introduction of desorbed analytes. The compounds sorbed onto particles extracted by the SPME fiber or trapped in the needle device were desorbed in the injector and no carry-over was observed. Both devices performed well in extracting airborne polycyclic aromatic hydrocarbons (PAHs) in diesel exhaust, triamcinolone acetonide in a dose of asthma drug and DEET in a dose of insect repellant spray. Results suggest that the NTDs and PDMS 7-microm fibers can be used for airborne particulate sampling and analysis, providing a simple, fast, reusable, and cost-effective screening tool. The advantage of the SPME fiber is the open-bed geometry allowing spectroscopic investigations of particulates; for example, with Raman microspectroscopy.

A generalized fecal glucocorticoid assay for use in a diverse array of nondomestic mammalian and avian species

Noninvasive fecal glucocorticoid analysis has tremendous potential as a means of assessing stress associated with environmental disturbance in wildlife. However, interspecific variation in excreted glucocorticoid metabolites requires careful selection of the antibody used in their quantification. We compared four antibodies for detecting the major fecal cortisol metabolites in yellow baboons following (3)H cortisol administration, ACTH challenge, and HPLC separation of fecal glucocorticoid metabolites. The most effective antibody (ICN corticosterone RIA; Cat. No. 07-120102) demonstrated relatively high cross-reactivities to the major cortisol metabolites present in feces during peak excretion, following both radiolabel infusion and ACTH challenge. This same antibody also detected increased fecal glucocorticoid metabolites after ACTH administration in the African elephant, black rhinoceros, Roosevelt elk, gerenuk, scimitar-horned oryx, Alaskan sea otter, Malayan sun bear, cheetah, clouded leopard, longtailed macaque, and northern spotted owl. Results suggest that (1) fecal glucocorticoid assays reliably detect endogenous changes in adrenal activity of a diverse array of species and (2) where comparisons were made, the ICN corticosterone antibody generally was superior to other antibodies for measuring glucocorticoid metabolites in feces.

Hormonal and clinical effects of chronic gonadotropin-releasing hormone agonist treatment in polycystic ovary syndrome

The aim of the study was to evaluate the hormonal (focusing on the urinary steroid profile) and clinical effects of chronic gonadotropin-releasing hormone (GnRH) agonist treatment in patients with polycystic ovary syndrome (PCOS) suffering from hirsutism. A long-acting GnRH agonist was administered for 6 months in eight PCOS patients. Hormonal effects were measured by determining serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, testosterone and estradiol concentrations, and by profiling urinary steroids using capillary gas chromatography of 24-hour urine samples. To evaluate 5 alpha-reductase enzyme activity, the ratios of androsterone to etiocholanolone and 5 alpha-tetrahydrocortisol to tetrahydrocortisol were calculated in urine samples. The ratio of androgen to cortisol metabolites was also determined before, and 3 and 6 months after therapy. LH and estradiol levels were suppressed significantly after the first injection and testosterone after the second injection of the GnRH agonist. Thus, serum testosterone was normalized. Ratios of urinary steroids reflecting 5 alpha-reductase enzyme activity (androsterone to etiocholanolone and 5 alpha-tetrahydrocortisol to tetrahydrocortisol) and the ratio of androgen to cortisol metabolites decreased significantly after 3 months of treatment. Degree of hirsutism, assessed by Ferriman-Gallwey score, diminished after 6 months, but not significantly. In conclusion, our data show that long-acting GnRH agonist treatment of PCOS patients is effective in reducing serum and urinary androgen levels, but it is not accompanied by an effective reduction in hirsutism during a 6-month treatment period. A longer or a combined treatment would be needed to achieve significant improvement in hirsutism. Gas chromatographic profiling of urinary steroids and the use of specific ratios of the excreted metabolites seems to be a sensitive tool both in the diagnosis of PCOS and in monitoring ovarian suppression.