Development of highly sensitive quantification method for testosterone and dihydrotestosterone in human serum and prostate tissue by liquid chromatography-electrospray ionization tandem mass spectrometry

Multiple exposures to heavy metals and changes in steroid hormones production in 4-year-old children

BACKGROUND

Prenatal exposure to multiple heavy metals can interfere with early neurodevelopment, lead to changes in sex hormone concentrations in children, and affect female reproductive health. To date, the influence of prenatal exposure to heavy metals on the endocrine system of children in Chinese electronic waste (e-waste) recycling areas has not been elucidated.

METHODS

Four weeks after delivery, 10 mL of human milk was collected for analysis of three heavy metals (lead (Pb), cadmium (Cd), and mercury (Hg)) via inductively coupled plasma mass spectrometry (ICP-MS). Four serum steroid hormones, including progesterone, testosterone, androstenedione (A-dione), and dehydroepiandrosterone (DHEA), were analyzed in 4-year-old children (25 boys and 17 girls). A multiple linear regression (MLR) model was implemented to investigate the association between each individual metal and serum steroid hormone. The exposure-response relationships were explored by generalized additive models (GAMs). Additionally, a Bayesian kernel machine regression (BKMR) model was used to assess the effects of multiple heavy metal exposures on each steroid hormone.

RESULTS

The MLR results show a significant positive association between a natural log unit increase in Hg and DHEA levels after adjusting for confounders (β = 65.50, 95% confidence interval (CI) = 4.37, 126.62). According to the GAM, the univariate exposure-response relationship of Hg on DHEA was almost linear. However, this association was attenuated based on the multiple metal MLR and BKMR results after accounting for multiple heavy metal exposures.

SIGNIFICANCE

Prenatal Hg exposure may affect sex hormones in children by affecting DHEA levels.

IMPACT STATEMENT

Prenatal maternal exposure to Hg may have long-term effects on the next generation. Hence, regulatory measures to reduce Hg exposure and long-term monitoring of children's health in e-waste areas are needed.

AAV-mediated gene therapy for patients' fibroblasts, iPS cells, and a mouse model of congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder caused by steroidogenic enzymes containing monogenetic defects. Most steroidogenic enzymes are cytochrome P450 groups that can be categorized as microsomal P450s, including 21-hydroxylase and 17α-hydroxylase/17,20 lyase, and mitochondrial P450s, including 11β-hydroxylase. It has been shown that ectopic administration of Cyp21a1 ameliorates steroid metabolism in 21-hydroxylase-deficient mice. However, the effectiveness of this approach for mitochondrial P450 has not yet been evaluated. In this study, primary fibroblasts from patients with 21-hydroxylase deficiency (CYP21A2D) (n=4), 17α-hydroxylase/17,20 lyase deficiency (CYP17A1D) (n=1), and 11β-hydroxylase deficiency (CYP11B1D) (n=1) were infected with adeno-associated virus type 2 (AAV2) vectors. Steroidogenic enzymatic activity was not detected in the AAV2-infected CYP11B1D fibroblasts. Induced pluripotent stem cells (iPSCs) of CYP11B1D were established and differentiated into adrenocortical cells by induction of the NR5A1 gene. Adrenocortical cells established from iPSCs of CYP11B1D (CYP11B1D-iPSCs) were infected with an adeno-associated virus type 9 (AAV9) vector containing CYP11B1 and exhibited 11β-hydroxylase activity. For an in vivo evaluation, we knocked out Cyp11b1 in mice by using the CRISPR/Cas9 method. Direct injection of Cyp11b1-containing AAV9 vectors into the adrenal gland of Cyp11b1-deficient mice significantly reduced serum 11-deoxycorticosterone/corticosterone ratios at 4 weeks after injection and the effect was prolonged for up to 12 months. This study indicated that CYP11B1D could be ameliorated by gene induction in the adrenal glands, which suggests that a defective-enzyme-dependent therapeutic strategy for CAH would be required. Defects in microsomal P450, including CYP21A2D and CYP17A1D, can be treated with extra-adrenal gene induction. However, defects in mitochondrial P450, as represented by CYP11B1D, may require adrenal gene induction.

Relationship between dioxins and steroid hormone in 6-year-olds: A follow-up study in an e-waste region of China

We conducted a follow-up observational study on the effects of dioxin exposure on the synthesis of steroid hormones in infants during the perinatal period. The participants included 42 pairs of mothers and infants that were previously studied in 2015. We analyzed four types of steroid hormones including progesterone, testosterone, androstenedione (A-dione), and dehydroepiandrosterone (DHEA) in the serum samples of 6-year-olds and the concentration of dioxins in breast milk. A multivariate linear regression was performed to associate steroid hormones (dependent variables) and dioxins with the body mass index (BMI), sex, age, and residence of participants (independent variables). The results were reported as β (standardized coefficient) and p-values. We found that dioxins have a significant negative correlation with DHEA and A-dione but no significant relationship with progesterone and testosterone. However, in previous studies, we found that testosterone and progesterone levels were significantly related to dioxins in 4-year-olds. We concluded that dioxins can affect the level of steroid hormones, but their effects fluctuate, and the harm caused by dioxins in children requires further long-term monitoring.

Decreased serum testosterone levels associated with 17β-hydroxysteroid dehydrogenase activity in 7-year-old children from a dioxin-exposed area of Vietnam

Since 2008, we have conducted epidemiological cohort studies on the relationship between dioxin exposure and disruption with children in the area sprayed with defoliants during the Vietnam War. In a long-term survey of children through the age of five, we observed androgen disruption due to decreased dehydroepiandrosterone (DHEA) and testosterone levels. In this study of 7-year-old, we separately elucidated androgen disruption for boys and girls, and discussed with respect to hormone disruption with sex differences on the steroid hormone biosynthesis process. This follow-up was conducted with 96 mother-child pairs in Vietnam (hotspot area: 45, non-sprayed area: 51). We took a questionnaire, the physical measurement and assayed 7 steroid hormones in their serum by LC-MS/MS. We examined the relationship between the hormone levels in the serum and dioxin levels in the maternal breast milk. The results showed that the serum DHEA level in the 7-year-old children in the hotspot recovered to levels in the non-sprayed area. The testosterone level of 66.5 pg/mL for boys in the non-sprayed area was 1.5 times the girls level of 44.6 pg/mL, a male-dominant effect. The testosterone level in boys and girls from the hotspot were significantly lower than in the non-sprayed area with no sex difference. The 17β-hydroxysteroid dehydrogenase (17β-HSD) activity was significantly higher in boys than in the girls from the non-sprayed area, but was significantly lower in the hotspot boys than in the non-sprayed area boys. Both the testosterone level and 17β-HSD activity in the boys were inversely correlated with the TEQ total PCDD/Fs in the maternal breast milk. These results indicated that dioxin delayed the expression of the testosterone level and 17β-HSD activity with growth in the 7-year-old boys. The serum DHEA in the 7-year-old children recovered to the levels of the children in the non-sprayed area.

Differential Effects of Focused Attention and Open Monitoring Meditation on Autonomic Cardiac Modulation and Cortisol Secretion

Mindfulness-based interventions (MBIs) have been used widely as a useful tool for the alleviation of various stress-related symptoms. However, the effects of MBIs on stress-related physiological activity have not yet been ascertained. MBIs primarily consist of focused-attention (FA) and open-monitoring (OM) meditation. Since differing effects of FA and OM meditation on brain activities and cognitive tasks have been mentioned, we hypothesized that FA and OM meditation have also differing effects on stress-related physiological activity. In this study, we examined the effects of FA and OM meditation on autonomic cardiac modulation and cortisol secretion. Forty-one healthy adults (aged 20-46 years) who were meditation novices experienced 30-min FA and OM meditation tasks by listening to instructions. During resting- and meditation-states, electrocardiogram transducers were attached to participants to measure the R-R interval, which were used to evaluate heart rate (HR) and perform heart rate variability (HRV) analyses. Saliva samples were obtained from participants pre- and post-meditation to measure salivary cortisol levels. Results showed that FA meditation induced a decrease in HR and an increase in the root mean square of successive differences (rMSDD). In contrast, OM meditation induced an increase in the standard deviation of the normal-to-normal interval (SDNN) to rMSSD ratio (SDNN/rMSSD) and a decrease in salivary cortisol levels. These results suggest that FA meditation elevates physiological relaxation, whereas OM meditation elevates physiological arousal and reduces stress.

Estrogen receptor 2b is the major determinant of sex-typical mating behavior and sexual preference in medaka

Male and female animals typically display innate sex-specific mating behaviors, which, in vertebrates, are highly dependent on sex steroid signaling. While estradiol-17β (E2) signaling through estrogen receptor 2 (ESR2) serves to defeminize male mating behavior in rodents, the available evidence suggests that E2 signaling is not required in teleosts for either male or female mating behavior. Here, we report that female medaka deficient for Esr2b, a teleost ortholog of ESR2, are not receptive to males but rather court females, despite retaining normal ovarian function with an unaltered sex steroid milieu. Thus, contrary to both prevailing views in rodents and teleosts, E2/Esr2b signaling in the brain plays a decisive role in feminization and demasculinization of female mating behavior and sexual preference in medaka. Further behavioral testing showed that mutual antagonism between E2/Esr2b signaling and androgen receptor-mediated androgen signaling in adulthood induces and actively maintains sex-typical mating behaviors and preference. Our results also revealed that the female-biased sexual dimorphism in esr2b expression in the telencephalic and preoptic nuclei implicated in mating behavior can be reversed between males and females by altering the sex steroid milieu in adulthood, likely via mechanisms involving direct E2-induced transcriptional activation. In addition, Npba, a neuropeptide mediating female sexual receptivity, was found to act downstream of E2/Esr2b signaling in these brain nuclei. Collectively, these functional and regulatory mechanisms of E2/Esr2b signaling presumably underpin the neural mechanism for induction, maintenance, and reversal of sex-typical mating behaviors and sexual preference in teleosts, at least in medaka.

Development of a Liquid Chromatography/Mass Spectrometry-Based Inhibition Assay for the Screening of Steroid 5-α Reductase in Human and Fish Cell Lines

Steroid 5-α reductase (5AR) is responsible for the reduction of steroids to 5-α reduced metabolites, such as the reduction of testosterone to 5-α dihydrotestosterone (DHT). A new adverse outcome pathway (AOP) for 5AR inhibition to reduce female reproduction in fish (AOP 289) is under development to clarify the antiestrogenic effects of 5AR inhibitors in female fish. A sensitive method for the DHT analysis using chemical derivatization and liquid chromatography–tandem mass spectrometry was developed. A cell-based 5AR inhibition assay that utilizes human cell lines, a transient overexpression system, and fish cell lines was developed. The measured IC₅₀ values of two well-known 5AR inhibitors, finasteride and dutasteride, were comparable in the different systems. However, the IC₅₀ of dutasteride in the fish cell lines was lower than that in the human cell lines. Finasteride showed a higher IC₅₀ against the RTG-2 cell line. These results demonstrated that 5ARs inhibition could differ in terms of structural characteristics among species. The assay has high sensitivity and reproducibility and is suitable for the application in 5AR inhibition screening for various endocrine disruption chemicals (EDCs). Future studies will continue to evaluate the quantitative inhibition of 5AR by EDCs to compare the endocrine-disrupting pathway in different species.

Derivatization with 2-hydrazino-1-methylpyridine enhances sensitivity of analysis of 5α-dihydrotestosterone in human plasma by liquid chromatography tandem mass spectrometry

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Quantitative analysis of low abundance androgens in human plasma.

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Quantitation of androgens over physiological range in men and post-menopausal women.

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Use of hydrazine derivatives improves analytical sensitivity.

Liquid Chromatography tandem mass spectrometry (LC-MS/MS) is the gold-standard approach for androgen analysis in biological fluids, superseding immunoassays in selectivity, particularly at low concentrations. While LC-MS/MS is established for analysis of testosterone and androstenedione, 5α-dihydrotestosterone (DHT) presents greater analytical challenges. DHT circulates at low nanomolar concentrations in men and lower in women, ionizing inefficiently and suffering from isobaric interference from other androgens. Even using current LC-MS/MS technology, large plasma volumes (>0.5 mL) are required for detection, undesirable clinically and unsuitable for animals. This study investigated derivatization approaches using hydrazine-based reagents to enhance ionization efficiency and sensitivity of analysis of DHT by LC-MS/MS. Derivatization of DHT using 2-hydrazino-1-methylpyridine (HMP) and 2-hydrazino-4-(trifluoromethyl)-pyrimidine (HTP) were compared. A method was validated using an UHPLC interfaced by electrospray with a triple quadruple mass spectrometer , analyzing human plasma (male and post-menopausal women) following solid-phase extraction. HMP derivatives were selected for validation affording greater sensitivity than those formed with HTP. HMP derivatives were detected by selected reaction monitoring (DHT-HMP m/z 396→108; testosterone-HMP m/z 394→108; androstenedione-HMP m/z 392→108). Chromatographic separation of androgen derivatives was optimized, carefully separating isobaric interferents and acceptable outputs for precision and trueness achieved following injection of 0.4 pg on column (approximately 34 pmol/L). HMP derivatives of all androgens tested could be detected in low plasma volumes: male (100 µL) and post-menopausal female (200 µL), and derivatives were stable over 30 days at -20°C. In conclusion, HMP derivatization, in conjunction with LC-MS/MS, is suitable for quantitative analysis of DHT, testosterone and androstenedione in low plasma volumes, offering advantages in sensitivity over current methodologies.

Determination of Intraprostatic and Intratesticular Androgens

Androgens represent the main hormones responsible for maintaining hormonal balance and function in the prostate and testis. As they are involved in prostate and testicular carcinogenesis, more detailed information of their active concentration at the site of action is required. Since the introduction of the term intracrinology as the local formation of active steroid hormones from inactive precursors of the adrenal gland, mainly dehydroepiandrosterone (DHEA) and DHEA-S, it is evident that blood circulating levels of sex steroid hormones need not reflect their actual concentrations in the tissue. Here, we review and critically evaluate available methods for the analysis of human intraprostatic and intratesticular steroid concentrations. Since analytical approaches have much in common in both tissues, we discuss them together. Preanalytical steps, including various techniques for separation of the analytes, are compared, followed by the end-point measurement. Advantages and disadvantages of chromatography-mass spectrometry (LC-MS, GC-MS), immunoanalytical methods (IA), and hybrid (LC-IA) are discussed. Finally, the clinical information value of the determined steroid hormones is evaluated concerning differentiating between patients with cancer or benign hyperplasia and between patients with different degrees of infertility. Adrenal-derived 11-oxygenated androgens are mentioned as perspective prognostic markers for these purposes.

Measurement of steroid hormones by liquid chromatography-tandem mass spectrometry with small amounts of hair

Steroid hormone levels in hair reflect the integrated values (average values) of hormone secretion over the past few months. We have used a method to evaluate diseases and chronic stress, discrimination of banned drug use, and so on. In contrast, the hair analysis methods reported so far required at least 10 mg (about 50 to 100 hair strands) of hair to analyze multiple steroid hormones from the same sample. Here, we developed a new method for measuring steroid hormones in hair by liquid chromatography-tandem mass spectrometry, which identifies multiple steroid hormones from 5 to 10 (about 1 mg) hair strands. Ten steroid hormones (cortisol, cortisone, testosterone, dihydrotestosterone, dehydroepiandrosterone, androstenedione, progesterone, pregnenolone, androstenediol and estradiol) covering from sex hormones to stress hormones were derivatized and measured by four different measuring systems. The method showed good linearity for all steroids with correlation coefficients of 0.999 or more. The accuracy and precision of intra- and inter-assay ranged from 96.0 to 106.4% and 4.8 to 8.1% for intra-assay, and from 96.9 to 104.9% and 6.9 and 10.6% for inter-assay, respectively. A mixed solution containing 0.1 M trifluoroacetic acid and 50% acetonitrile was used to extract hair and to enhance the cortisol extraction efficiency approximately twice compared to the previously reported extraction with methanol. This method has the potential to clarify the relationship between steroid hormone levels and diseases that show alopecia such as chronic stress and androgenetic alopecia.

Fully automated method for quantitative determination of steroids in serum: An approach to evaluate steroidogenesis

Steroidogenesis is a set of metabolic reactions where the enzymes play a key role to control the physiological levels of steroids. A deficiency in steroidogenesis induces an accumulation and/or insufficiency of steroids in human blood and can lead to different pathologies. This issue added to the low levels of steroids (pg mL^-1 to ng mL^-1) in this biofluid make of their determination an analytical challenge. In this research, we present a high-throughtput and fully automated method based on solid-phase extraction on-line coupled to liquid chromatography with tandem mass spectrometry detection (SPE-LC-MS/MS) to quantify estrogens (estrone and estradiol), androgens (testosterone, androstenedione, dihydrotestosterone and dehydroepiandrosterone), progestogens (progesterone, pregnenolone, 17-hydroxyprogesterone and 17-hydroxypregnenolone), glucocorticoids (21-hydroxyprogesterone, 11-deoxycortisol, cortisone, corticosterone and cortisol) and one mineralocorticoid (aldosterone) in human serum. The performance of the SPE step and the multiple reaction monitoring (MRM) mode allowed reaching a high sensitivity and selectivity levels without any derivatization reaction. The fragmentation mechanisms of the steroids were complementary studied by LC-MS/MS in high-resolution mode to confirm the MRM transitions. The method was characterized with two SPE sorbents with similar physico-chemical properties. Thus, limits of quantification were at pg mL^-1 levels, the variability was below 25% (except for pregnenolone and cortisone), and the accuracy, expressed as bias, was always within ±25%. The proposed method was tested in human serum from ten volunteers, who reported levels for the sixteen target steroids that were satisfactorily in agreement with the physiological ranges reported in the literature.

The association between dioxins and steroid hormones in general adult males: a cross-sectional study in an e-waste region of China

As observed among residents in electronic waste (e-waste) recycling areas, dioxins can disrupt the homeostasis of endocrine hormones and the balance of thyroid hormones. Few studies, however, have examined whether e-waste recycling activities influence steroid hormone equilibrium in the general adult male population. This study evaluated the association between steroid hormones and the physical burdens of dioxins in the general adult male population residing in an e-waste region. In September 2017, 74 adult males residing in an e-waste dismantling region were enrolled in the current study. Approximately 10 mL of blood was collected from each adult male, and the serum samples were separated through centrifugation. Then, the levels of dioxin and steroid hormones in the serum of the participants were measured. We treated dioxin levels as categorical variables in the general linear model according to quartiles (25, 50, and 75 percentile). Comparing the findings with a reference group (< 25th percentile), we noted significantly higher dehydroepiandrosterone (DHEA) level in men with low serum polychlorinated dibenzofuran-toxic equivalent (PCDFs-TEQ) level between 3.80 and 6.31 pg/g lipid (1933 vs. 1447 pg/ml) and low polychlorinated dibenzo-p-dioxins and dibenzofurans-TEQ (PCDD/PCDFs-TEQ) between 8.57 and 15.11 pg/g lipid (1996 vs. 1360 pg/ml). Moreover, a significantly higher androstenedione (A-dione) level was found in men whose serum PCDFs-TEQ ≥ 11.34 pg/g lipd (2404 vs. 1848). What's more, there were significantly higher 3β-hydroxysteroid dehydrogenase (3β-HSD) concentrations in low- and high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) groups (1.30-1.67 and ≥ 2.64 pg-TEQ/g lipid, respectively with 719 and 807 vs. 496, respectively). Our findings suggest that specific dioxin exposure may disturb normal DHEA, A-dione levels, and enzyme activity in the general adult male population in an e-waste region of China.

Association of dioxin in maternal breast milk and salivary steroid hormone levels in preschool children: A five-year follow-up study of a Vietnam cohort

Recent studies have found elevated dioxin levels inside some former US military air bases in Vietnam, known as hotspots. The aim of the present study was to evaluate the association of dioxin exposure and steroid hormone in preschool children in Vietnam. In 2010, 2011, 52 primiparae mother-infant pairs in the hotspot and 52 pairs in a non-exposure region were enrolled. For the final analysis, 26 vs 26 pairs were selected, who participated at all three surveys. Univariable and multivariable linear regressions were used to evaluate associations between hormone and dioxin congeners. Geometric mean total TEQ of PCDD/DFs in the hotspot were significantly higher than in the non-exposure region, 8.7 and 3.4 pg TEQ/g lipid, respectively. In the hotspot, salivary dehydroepiandrosterone (DHEA) was significantly higher in 1-year-old children (Boys = 123 pg/mL, Girls = 120 pg/mL) than in the non-exposure region (Boys = 28 pg/mL, Girls = 27 pg/mL). In contrast, DHEA was significantly lower in 5-year-old children (Boys = 70 pg/mL, Girls = 106 pg/mL) in the hotspot than in the non-exposure region (Boys = 496 pg/mL, Girls = 654 pg/mL). Salivary testosterone was significantly lower in the hotspot (Boys = 1.9 pg/mL, Girls = 1.9 pg/m; Boys = 1.0 pg/mL, Girls = 1.1 pg/mL, respectively) than in the non-exposure region (Boys = 3.7 pg/mL, Girls = 3.8 pg/m; Boys = 5.7 pg/mL, Girls = 7.0 pg/mL, respectively) at 3 years and 5 years of age. Higher levels of highly chlorinated dioxins in breast milk were associated with higher DHEA in 1-year-old and lower DHEA and testosterone levels in 5-year-old children. Our findings indicated that dioxins were associated with changes of DHEA and testosterone levels in preschool Vietnamese children.

UPLC-MS/MS determination of steroid hormones via a novel reaction based on derivatisation by a cyclic-organophosphate

A cyclic-organophosphate, specifically 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide, was used to derivatise the hydroxyl group at the C3 position of selected steroid hormones to analyse the derivatives using UPLC-MS/MS (ultra-performance liquid chromatography-tandem mass spectrometry). Reactions were performed in an anhydrous pyridine environment in the presence of AlCl₃ at 50 °C. The developed reaction is suitable for analytical chemistry applications and was validated by analysis of selected contraceptive drugs. The sensitivity of the method depends on hormone tested and the limit of detection ranges from 130 pg/mL for β-estradiol to 240 pg/mL for estriol. The estimated efficiency of derivatisation reactions varies in the range from 77.5 to 95.7%, and depends upon the hormone undergoing derivatisation. The method's recovery rate for the lowest concentration tested (800 pg/mL) is 88.1-96.3%. The method exhibits linearity in the 390 pg/mL to 2.5 μg/mL range, with R² = 0.997. The developed steroid hormone derivatisation reaction was validated experimentally using UHPLC-QTOF-MS (ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry) and NMR (nuclear magnetic resonance) spectroscopy. These studies show that the developed derivatisation reaction provides a precise and repeatable determination of selected steroid hormones in contraceptive drugs. At n = 10, CV (Coefficient of Variation) did not exceed 7%, which is a very good result compared with other analytical methods.

Quantitative-Profiling Method of Serum Steroid Hormones by Hydroxylamine-Derivatization HPLC-MS

A sensitive and rapid high performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed and validated for simultaneous quantification of ten steroid hormones, including estrogens, androgens, progesterones, and corticosteroids four classes of steroids. The following ten steroid hormones were analyzed: progesterone, 21-deoxycortisol, estrone, 4-androstenedione, testosterone, dihydro-testosterone, androstenone, dehydroepiandrosterone, corticosterone and cortisone. Stable deuterated isotopes were used as internal standards for quantification. Sample preparation with and without derivatization were performed after liquid-liquid extraction, and the corresponding results were compared according to sensitivity and selectivity. Hydroxylamine derivatization was found to improve the ionization efficiency of the analytes for electrospray ionization MS analysis. The gradient of mobile phase and experimental parameters for HPLC separation were optimized. The lower limits of quantification were in the range of 0.05-5 ng mL^-1 with wide linear range for the ten steroid hormones. The intra-day precision < 11.1% and recovery of 84.5-120% with negligible matrix effect were achieved, where within the acceptance limits of the FDA guideline. Total HPLC-MS analysis time was 6 min. This method enables simultaneous quantification of steroids in human serum. It will be helpful for the serum steroid profiling in order to understand various endocrinology diseases.

Sex steroids in serum and prostatic tissue of human cancerous prostate (STERKPROSER trial)

BACKGROUND

Currently, there is no consensus regarding the expected concentration levels of intra-prostatic sex steroids in patients with Prostate Cancer (PCa). Our objective was to assess the concentration levels of sex steroids in prostatic tissue and serum, in two cohorts of patients with localized PCa or benign prostatic hyperplasia (BPH).

METHODS

Between September 2014 and January 2017, men selected for radical cystectomy (for bladder cancer) or open prostatectomy (for BPH), and men selected for radical prostatectomy for localized PCa were included. Blood samples were collected at baseline before surgery, and steroid concentrations were assessed following the recommendations of the Endocrine Society. Intra-prostatic samples were collected from fresh surgical samples, and assessed by gas chromatography and mass spectrometry (GC/MS). Permanova analysis was performed. Analyses were adjusted for age, prostate weight, and prostate-specific antigen (PSA) level.

RESULTS

A total of 73 patients (41 patients with PCa and 32 patients with BPH) were included in this study. Patients with PCa were younger, and had smaller prostate volumes with higher levels of PSA. The levels of Total Testosterone (TT), Di-Hydro-Testosterone (DHT), and Estradiol (E2) in the serum were not significantly different between PCa and BPH. In PCa tissue, TT concentrations were significantly lower (0.11 ng/g vs 0.47 ng/g, P = 0.0002), however its derivative E2 had significantly higher concentrations (31.0 ng/g vs 22.3 ng/g, P = 0.01). DHT tissue concentrations were not significantly different between the two groups (5.55 ng/g vs 5.42 ng/g, P = 0.70). Intra-prostatic TT concentrations were significantly lower in the peripheral zone than in the central zone for the CaP group (0.07 ng/g vs 0.15 ng/g, P = 0.004).

CONCLUSIONS

Patients with PCa had lower intra-prostatic TT and higher E2 concentrations levels compared to the patients with BPH. PCa seem to consume more TT and produce more E2, especially in the peripheral zone.

Simultaneous measurement of 18 steroids in human and mouse serum by liquid chromatography-mass spectrometry without derivatization to profile the classical and alternate pathways of androgen synthesis and metabolism

BACKGROUND

The recently identified alternate, or backdoor, pathway of DHT synthesis provides important novel information on androgen biosynthesis beyond the classical pathway. We report a rapid and versatile liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to simultaneously and accurately quantify key steroids in human or mouse serum involved in either the classical or backdoor androgen synthesis pathways.

METHODS

Serum (200 µL) fortified with isotopically labelled internal standards underwent liquid-liquid extraction (LLE) with MTBE and extracts were analysed on a LC-MS/MS. The targeted steroids for quantification were testosterone (T), dihydrotestosterone (DHT), 5α-androstane-3α,17β-diol (3α diol), 5α-androstane-3β,17β-diol (3β diol), dehydroepiandrosterone (DHEA), androstenedione (A4), androsterone (AD), estradiol (E2), estrone (E1), progesterone (P4), pregnenolone (P5), androstenediol (Adiol), 17-hydroxyprogesterone (17-OHP4) and 17-hydroxypregnenolone (17-OHP5), corticosterone (B), cortisol (F), allopregnanolone (Allo-P5) and dihydroprogesterone (DHP).

RESULTS

The limits of quantification (LOQ) were 5 pg/mL for E2 and E1, 25 pg/mL for T, 50 pg/mL for A4 and 0.10 ng/mL for DHT, 17OHP5, P4, P5, AD, Adiol, DHEA, AlloP5 and 0.20 ng/mL for 17OHP4, 3α diol, 3β diol, DHP, 0.25 ng/mL for B and 1 ng/mL for F. Accuracy, precision, reproducibility and recovery were within acceptable limits for bioanalytical method validation. The method is illustrated in human and mouse, male and female serum.

CONCLUSIONS

The presented method is sufficiently sensitive, specific and reproducible to meet the quality criteria for routine laboratory application for accurate quantitation of 18 steroid concentrations in male and female serum from humans or mice for the purpose of profiling androgen synthesis and metabolism pathways.

Androgen disruption by dioxin exposure in 5-year-old Vietnamese children: Decrease in serum testosterone level

Dioxins have been suspected to be potential substances causing endocrine disruptions in humans. We are conducting the research in one of three dioxin exposure areas (hotspots) in Vietnam. We previously reported that the salivary dehydroepiandrosterone (DHEA) level decreased in 3-year-old Vietnamese children and that it was significantly inversely correlated with polychlorinated dibenzodioxin/dibenzofuran levels in their mother's breast milk. In this study, we investigated the influence of exposure to dioxin on steroid hormone biosynthesis in the same children when they reached 5 years of age, focusing on androgens. Thirty-five and 50 mother-child pairs from dioxin hotspot and non-sprayed areas, respectively, participated in this study. Maternal breast milk was donated at 4 to 16 weeks postpartum in 2008 to measure dioxin levels by gas chromatography/high-resolution mass spectrometry. Serum was collected from 5-year-old children in 2013. Seven steroid hormones were measured by liquid chromatography/mass spectrometry. Most dioxin congeners in breast milk were 2- to 10-fold higher in the hotspot than in the non-sprayed area. DHEA and testosterone (T) were significantly lower in the hotspot and showed negative correlations with most dioxin congeners. Similar results were observed for the activities of cytochrome P450-17, 20 lyase (CYP17 lyase), and 17β-hydroxysteroid dehydrogenase (HSD). Conversely, the elevated androstenedione (A-dione) level and 3β-HSD activity in children from the hotspot were positively correlated with dioxin levels. Moreover, a positive correlation was shown between T and 17β-HSD. It is possible that dioxin inhibits 17β-HSD activity, leading to a decrease in the T level. Multiple regression analysis indicated that dioxin had a strong association with the DHEA, A-dione, and T levels. In conclusion, the present study suggests that dioxin is associated with low levels of DHEA and T and inhibition of the activity of steroidogenic enzymes such as CYP17 lyase and 17β-HSD in 5-year-old children.

Simultaneous determination of dihydrotestosterone and its metabolites in mouse sera by LC-MS/MS with chemical derivatization

Androgens play a vital role in prostate cancer development, and their elimination and blockade are essential in the disease management. DHT is the key ligand for androgen receptor (AR) in the prostate. It is locally synthesized from testosterone. In the prostate, DHT is predominantly metabolized to α-diol and β-diol. Recent studies indicate that impaired DHT catabolism is associated with prostate cancer, signifying the necessity of a sensitive quantitative method for the determination of DHT and its metabolites. In this work, an LC-MS/MS method for the simultaneous quantification of DHT and its metabolites was developed and validated. Steroid-free sera were prepared and used for the preparation of sera calibrators and quality controls (QCs). DHT and its metabolites along with their respective stable heavy isotope labeled analytes representing internal standards were first extracted with methyl tertiary-butyl ether (MTBE) and derivatized with picolinic acid (PA). The derivatized analytes were then extracted again with MTBE, dried under nitrogen and reconstituted in the mobile phase (80% methanol and 0.2% formic acid in water). Baseline chromatographic separation of the derivatized analytes was achieved isocratically on XTerra C18 column (2.1 × 100 mm) using the mobile phase at a flow rate of 0.25 mL/min. Quantitation was performed using multiple-reaction-monitoring mode with positive electrospray ionization. The method has calibration ranges from 0.0500 ng/mL to 50.0 ng/mL for DHT and its two metabolites with acceptable assay precision, accuracy, recovery, and matrix factor. It was applied to the determination of DHT and its metabolites in an animal study.

Correlation Between Resting Testosterone/Cortisol Ratio and Sound-Induced Vasoconstriction at Fingertip in Men

A sound-induced sympathetic tone has been used as an index for orienting responses to auditory stimuli. The resting testosterone/cortisol ratio is a biomarker of social aggression that drives an approaching behavior in response to environmental stimuli, and a higher testosterone level and a lower cortisol level can facilitate the sympathetic response to environmental stimuli. Therefore, it is possible that the testosterone/cortisol ratio is correlated with the sound-induced sympathetic tone. The current study investigated the relationship between the resting testosterone/cortisol ratio and vasoconstriction induced by listening to sound stimuli. Twenty healthy males aged 29.0 ± 0.53 years (mean ± S.E.M) participated in the study. They came to the laboratory for 3 days and listened to one of three types of sound stimuli for 1 min on each day. Saliva samples were collected for an analysis of salivary testosterone and cortisol levels on the day of each experiment. After the collecting the saliva sample, we measured the blood volume pulse (BVP) amplitude at a fingertip. Since vasoconstriction is mediated by the activation of the sympathetic nerves, the strength of the reduction in BVP amplitude at a fingertip was called the BVP response (finger BVPR). No difference was observed between the sound-induced finger BVPR for the three types of sound stimuli (p = 0.779). The correlation coefficient between the sound-induced finger BVPR and the salivary testosterone/cortisol ratio within participants was significantly different from no correlation (p = 0.011) and there was a trend toward a significance in the correlation between the sound-induced finger BVPR and the salivary testosterone/cortisol ratio between participants (r = 0.39, p = 0.088). These results suggest that the testosterone/cortisol ratio affects the difference in the sound-evoked sympathetic response.

A sensitive approach for simultaneous quantification of carbonyl and hydroxyl steroids using 96-well SPE plates based on stable isotope coded-derivatization-UPLC-MRM: method development and application

Steroid hormones are crucial substances that mediate a wide range of vital physiological functions. Because of the important biological significance of steroids, this paper presents a new targeted metabolic method based on adding stable isotope tags to hydroxyl containing and carbonyl containing steroid hormones with two pairs of synthesized derivatization reagents: deuterium 4-(dimethylamino)-benzoic acid (D₄-DMBA), and D₅-Girard P (D₅-GP) using of ultra performance liquid chromatography-multiple reaction monitoring (UPLC-MRM). Firstly, an Oasis PRiME hydrophilic-lipophilic balance (HLB) 96-well solid phase extraction plate was used to pretreat a number of biological samples simultaneously. Secondly, hydroxyl and carbonyl steroids were labeled using two pairs of synthetic reagents, namely DMBA and D₄-DMBA, and GP and D₅-GP, respectively. Thirdly, the mixed products were detected using UPLC-MRM and the mass spectroscopy conditions were optimized. Methodology development showed that the sensitivity was enhanced 1 to >500-fold. Finally, the new method was applied to analysis of urine samples of healthy males, females and rats. The results revealed that the method can be sensitive and reliable for simultaneous quantification of steroid hormones containing hydroxyl and carbonyl groups in 12 min in a single run. This method provided a powerful tool for studying the metabolic mechanism of steroids and contributed to the development of targeted metabolomics.

Steroid hormones are crucial substances that mediate a wide range of vital physiological functions.

A relationship in adrenal androgen levels between mothers and their children from a dioxin-exposed region in Vietnam

Over the past decades, southern Vietnam has been burdened by dioxins from contaminated herbicides sprayed during the Vietnam War. In a previous study, we found that dioxin exposure decreased levels of salivary dehydroepiandrosterone (DHEA), an adrenal androgen, in 3-year-old children. In present study, to assess the relationship between adrenal hormones disruption in lactating mothers and in children, we compared mother-child pairs from dioxin- and nondioxin-contaminated regions. In 2010 and 2011, mother-child pairs from a dioxin hotspot region (n=37) and a non-contaminated region (n=47) were recruited and donated breast milk and serum samples for dioxin and steroid hormones determination. Mothers were 20-30years old and had given birth to their first child between 4 and 16weeks previously. One year later, saliva samples were collected from the children. Dioxin levels in breast milk were determined by gas chromatography/high-resolution mass spectrometry. Salivary DHEA, cortisol in children and androstenedione (A-dione), estradiol, cortisol, and DHEA in maternal serum were analyzed by liquid chromatography/tandem mass spectrometry. Concentrations of dioxin congeners in the hotspot region were 2- to 5-fold higher than in samples from the non-contaminated region. Salivary DHEA levels in children and serum A-dione levels in mothers were significantly higher in the hotspot region; no difference was found in the levels of other hormones. Moreover, there was a significant positive correlation between the elevated hormone levels in mothers and children (r=0.62, p<0.001). Several dioxin congeners exhibited strong significant dose-response relationships with salivary DHEA and serum A-dione levels. Our findings suggest that dioxin disrupts adrenal androgens in mothers and breastfeeding children through the same mechanism.

Increase in salivary oxytocin and decrease in salivary cortisol after listening to relaxing slow-tempo and exciting fast-tempo music

Relaxation and excitation are components of the effects of music listening. The tempo of music is often considered a critical factor when determining these effects: listening to slow-tempo and fast-tempo music elicits relaxation and excitation, respectively. However, the chemical bases that underlie these relaxation and excitation effects remain unclear. Since parasympathetic and sympathetic nerve activities are facilitated by oxytocin and glucocorticoid, respectively, we hypothesized that listening to relaxing slow-tempo and exciting fast-tempo music is accompanied by increases in the oxytocin and cortisol levels, respectively. We evaluated the change in the salivary oxytocin and cortisol levels of participants listening to slow-tempo and fast-tempo music sequences. We measured the heart rate (HR) and calculated the heart rate variability (HRV) to evaluate the strength of autonomic nerve activity. After listening to a music sequence, the participants rated their arousal and valence levels. We found that both the salivary oxytocin concentration and the high frequency component of the HRV (HF) increased and the HR decreased when a slow-tempo music sequence was presented. The salivary cortisol level decreased and the low frequency of the HRV (LF) to HF ratio (LF/HF) increased when a fast-tempo music sequence was presented. The ratio of the change in the oxytocin level was correlated with the change in HF, LF/HF and HR, whereas that in the cortisol level did not show any correlation with indices of autonomic nerve activity. There was no correlation between the change in oxytocin level and self-reported emotions, while the change in cortisol level correlated with the arousal level. These findings suggest that listening to slow-tempo and fast-tempo music is accompanied by an increase in the oxytocin level and a decrease in the cortisol level, respectively, and imply that such music listening-related changes in oxytocin and cortisol are involved in physiological relaxation and emotional excitation, respectively.

The Simultaneous measurement of serum testosterone and 5α-dihydrotestosterone by gas chromatography-mass spectrometry (GC-MS)

BACKGROUND

Simultaneous measurement of testosterone (T) and 5α-dihydrotestosterone (DHT) is important for diagnosing androgen deficiency states and hyperandrogenism in males and females, respectively. However, immunoassays used for T and DHT determination suffer from inadequate specificity and sensitivity, while tandem mass spectrometry is expensive and demanding in use.

METHODS AND RESULTS

We developed a selective gas chromatography-mass spectrometry (GC-MS) method for parallel T and DHT measurement. The assay showed a linear response up to 46.5nmol/L, intra- and interassay imprecision and inaccuracy <15% and recoveries in spiked samples >90% for both analytes. The limit of quantitation was 0.117nmol/L for T and 0.168nmol/L for DHT. Comparison with immunoassays revealed good agreement for T in males, but a bias in favour of immunoassays at low concentrations for T in females and DHT in both sexes. We established reference ranges for T and DHT and suggest interval partitioning for T according to age in men and menstrual cycle in women. Assay validation in a clinical setting suggests that measuring DHT or T/DHT ratio may help identify patients with polycystic ovary syndrome.

CONCLUSION

We developed a selective, simple and inexpensive GC-MS method for parallel measurement of T and DHT with potential use in the clinical laboratory.

Circulating steroid hormone variations throughout different stages of prostate cancer

Steroid hormones play a central role in the maintenance and progression of prostate cancer. The androgen receptor is the primary driver of tumor cell proliferation and is activated by the androgens testosterone and 5α-dihydrotestosterone. Inhibition of this pathway through medical or surgical castration improves survival in the majority of advanced prostate cancer patients. However, conversion of adrenal androgen precursors and alternative steroidogenic pathways have been found to contribute to tumor progression and resistance to treatment. The emergence of highly accurate detection methods allows us to study steroidogenic mechanisms in more detail, even after treatment with potent steroidogenic inhibitors such as the CYP17A1 inhibitor abiraterone. A clear overview of steroid hormone levels in patients throughout the local, metastatic and castration-resistant stages of prostate cancer and treatment modalities is key toward a better understanding of their role in tumor progression and treatment resistance. In this review, we summarize the currently available data on steroid hormones that have been implicated in the various stages of prostate cancer. Additionally, this review addresses the implications of these findings, highlights important studies in this field and identifies current gaps in literature.

Relationships between Circulating and Intraprostatic Sex Steroid Hormone Concentrations

Background: Sex hormones have been implicated in prostate carcinogenesis, yet epidemiologic studies have not provided substantiating evidence. We tested the hypothesis that circulating concentrations of sex steroid hormones reflect intraprostatic concentrations using serum and adjacent microscopically verified benign prostate tissue from prostate cancer cases.Methods: Incident localized prostate cancer cases scheduled for surgery were invited to participate. Consented participants completed surveys, and provided resected tissues and blood. Histologic assessment of the ends of fresh frozen tissue confirmed adjacent microscopically verified benign pathology. Sex steroid hormones in sera and tissues were extracted, chromatographically separated, and then quantitated by radioimmunoassays. Linear regression was used to account for variations in intraprostatic hormone concentrations by age, body mass index, race, and study site, and subsequently to assess relationships with serum hormone concentrations. Gleason score (from adjacent tumor tissue), race, and age were assessed as potential effect modifiers.Results: Circulating sex steroid hormone concentrations had low-to-moderate correlations with, and explained small proportions of variations in, intraprostatic sex steroid hormone concentrations. Androstane-3α,17β-diol glucuronide (3α-diol G) explained the highest variance of tissue concentrations of 3α-diol G (linear regression r2 = 0.21), followed by serum testosterone and tissue dihydrotestosterone (r2 = 0.10), and then serum estrone and tissue estrone (r2 = 0.09). There was no effect modification by Gleason score, race, or age.Conclusions: Circulating concentrations of sex steroid hormones are poor surrogate measures of the intraprostatic hormonal milieu.Impact: The high exposure misclassification provided by circulating sex steroid hormone concentrations for intraprostatic levels may partly explain the lack of any consistent association of circulating hormones with prostate cancer risk. Cancer Epidemiol Biomarkers Prev; 26(11); 1660-6. ©2017 AACR.

The relationship between dioxins exposure and risk of prostate cancer with steroid hormone and age in Vietnamese men

Although Vietnam's massive herbicide exposure in 1960s and 1970s was clearly injurious to health, not all causal relationships have been clarified. We therefore explored associations among dioxins, steroid hormones, age and prostate cancer risk in men. We compared serum levels of dioxin, steroid hormones and prostate specific antigen (PSA) in men aged 56-81years from herbicide-exposed hotspots (n=50) with those from non-sprayed regions (n=48). Mean serum levels of dioxin congeners in the hotspot group were 1.5-11.3 times higher than the non-sprayed group depending on specific compound. Levels of testosterone, estradiol and 3β-hydroxysteroid dehydrogenase (3β-HSD) activity in the hotspot group were also significantly higher than in non-sprayed group. Estradiol levels were significantly related to levels of several specific dioxin derivatives in both group. Significant positive correlations were also found between DHT and 1234678-HpCDD or 1234678-HpCDF; and between 3β-HSD activity and 123678-HxCDD, 123478-HxCDF, 123678-HxCDF, or HxCB#169. After adjusting for age, body mass index, and tobacco use, multiple linear regressions showed levels of dihydrotestosterone (DHT), estradiol, testosterone and 3β-HSD activity were not associated with dioxins in the two groups; however, levels of DHT, testosterone and 3β-HSD activity increased significantly with age in the hotspot group. The hotspot and non-sprayed groups did not significantly differ in PSA levels. But six of the hotspot subjects had PSA levels >3ng/mL, 3 of whom were suspected to have prostate cancer (PC) after digital rectal examination. Our findings suggest that dioxin exposure can lead to increased levels of several sex steroid hormones with age. The correlation of dioxin with steroid hormone levels and prostate cancer risk should be studied further.

ACSL3 promotes intratumoral steroidogenesis in prostate cancer cells

Long‐chain acyl‐coenzyme A (CoA) synthetase 3 (ACSL3) is an androgen‐responsive gene involved in the generation of fatty acyl‐CoA esters. ACSL3 is expressed in both androgen‐sensitive and castration‐resistant prostate cancer (CRPC). However, its role in prostate cancer remains elusive. We overexpressed ACSL3 in androgen‐dependent LNCaP cells and examined the downstream effectors of ACSL3. Furthermore, we examined the role of ACSL3 in the androgen metabolism of prostate cancer. ACSL3 overexpression led to upregulation of several genes such as aldo‐keto reductase 1C3 (AKR1C3) involved in steroidogenesis, which utilizes adrenal androgen dehydroepiandrosterone sulfate (DHEAS) as substrate, and downregulated androgen‐inactivating enzyme UDP‐glucuronosyltransferase 2 (UGT2B). Exposure to DHEAS significantly increased testosterone levels and cell proliferative response in ACSL3‐overexpressing cells when compared to that in control cells. A public database showed that ACSL3 level was higher in CRPC than in hormone‐sensitive prostate cancer. CRPC cells showed an increased expression of ACSL3 and an expression pattern of AKR1C3 and UGT2B similar to ACSL3‐overexpressing cells. DHEAS stimulation significantly promoted the proliferation of CRPC cells when compared to that of LNCaP cells. These findings suggest that ACSL3 contributes to the growth of CRPC through intratumoral steroidogenesis (i.e. promoting androgen synthesis from DHEAS and preventing the catabolism of active androgens).

Testosterone and dihydrotestosterone levels in the transition zone correlate with prostate volume

BACKGROUND

There is still no consensus regarding intraprostatic androgen levels and the accumulation of androgens in the hyperplastic prostatic tissue. The current opinion is that intraprostatic dihydrotestosterone (DHT) concentrations are maintained but not elevated in benign prostatic hyperplasia (BPH), while there is no similar data concerning intraprostatic testosterone (T).

METHODS

Tissue T (tT) and tissue DHT (tDHT) concentration were determined in 93 patients scheduled for initial prostate biopsy. The criteria for biopsy were abnormal DRE and/or PSA > 4 ng/mL. Total prostate volume (TPV) was determined by transrectal ultrasound (TRUS). During TRUS- guided prostate biopsy, 10-12 samples were collected from the peripheral zone (PZ) and two additional samples were collected from the transition zone (TZ). The samples from the TZ were immediately frozen in liquid nitrogen at -70°C, and transported for tissue androgen determination, using liquid chromatography mass spectrometry (LC-MS).

RESULTS

Pathological analysis revealed that prostate cancer (PCa) was present in 45 and absent in 48 patients. In the whole group, there were 42 men with small prostate (TPV < 30 mL) and 51 with enlarged prostate (TPV ≥ 31 mL). The overall average tT level was 0.79 ± 0.66 ng/g, while the average tDHT level was 10.27 ± 7.15 ng/g. There were no differences in tT and tDHT level in prostates with and without PCa. However, tT and tDHT levels were significantly higher in larger, than in smaller prostates (tT: 1.05 ± 0.75 and 0.46 ± 0.29 ng/g, and tDHT: 15.0 ± 6.09 and 4.51 ± 2.75 ng/g, respectively). There were strong correlations between tT and TPV (r = 0.71), and tDHT and TPV (r = 0.74).

CONCLUSIONS

The present study confirmed that both T and DHT accumulated in the stroma of enlarged prostates; the degree of accumulation correlated with prostate volume.

Development of LC-MS/MS Confirmatory Method for the Determination of Testosterone in Bovine Serum

Introduction

In the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level.

Material and Methods

17β-testosterone and internal standards of 17%-testosterone-d2 were extracted from serum samples with a mixture of tert-butyl methyl ether/petroleum ether and were directly analysed by an LC/MS/MS on QTRAP 5500 instrument with a TurboIon-Spray source operating in a positive ionisation mode. Chromatographic separation was achieved on the analytical column Inertsil® ODS-3 with an isocratic elution using mobile phase consisting of acetonitrile, methanol, and water. Method validation has been carried out in accordance with the Commission Decision 2002/657/EC.

Results

The method was characterised by good recovery (82%) and precision (R.S.D 17 %). Decision limit (CCα) and detection capability (CCβ) was 0.05 μg L⁻¹ and 0.09 μg L⁻¹ respectively. The method met the criteria set out in Commission Decision 2002/657/EC for the purpose of confirmation in terms of retention time and ion ratio in the whole range of its application.

Conclusions

The developed method is specific and sensitive, suitable for measuring the natural level of testosterone in blood of cattle and for use in routine control programme for the detection of this hormone in bovine serum.

Simultaneous quantitation of nine hydroxy-androgens and their conjugates in human serum by stable isotope dilution liquid chromatography electrospray ionization tandem mass spectrometry

Castration resistant prostate cancer (CRPC), the fatal form of prostate cancer, remains androgen dependent despite castrate levels of circulating testosterone (T) and 5α-dihydrotestosterone (DHT). To investigate mechanisms by which the tumor can synthesize its own androgens and develop resistance to abiraterone acetate and enzalutamide, methods to measure a complete androgen profile are imperative. Here, we report the development and validation of a stable isotope dilution liquid chromatography electrospray ionization tandem mass spectrometric (SID-LC-ESI-MS/MS) method to quantify nine human hydroxy-androgens as picolinates, simultaneously with requisite specificity and sensitivity. In the established method, the fragmentation patterns of all nine hydroxy-androgen picolinates were identified, and [13C3]-5α-androstane-3α, 17β-diol and [13C3]-5α-androstane-3β, 17β-diol used as internal standards were synthesized enzymatically. Intra-day and inter-day precision and accuracy corresponds to the U.S. Food and Drug Administration Criteria for Bioanalytical Method Validation. The lower limit of quantitation (LLOQ) of nine hydroxy-androgens is 1.0pg to 2.5pg on column. Diols which have been infrequently measured: 5-androstene-3β, 17β-diol and 5α-androstane-3α, 17β-diol can be determined in serum at values as low as 1.0pg on column. The method also permits the quantitation of conjugated hydroxy-androgens following enzymatic digestion. While direct detection of steroid conjugates by electrospray-ionization tandem mass spectrometry has advantages the detection of unconjugated and conjugated steroids would require separate methods for each set of analytes. Our method was applied to pooled serum from male and female donors to provide reference values for both unconjugated and conjugated hydroxy-androgens. This method will allow us to interrogate the involvement of the conversion of 5-androstene-3β, 17β-diol to T, the backdoor pathway involving the conversion of 5α-androstane-3α, 17β-diol to DHT and the inactivation of DHT to 5α-androstane-3β, 17β-diol in advanced prostate cancer.

High serum dihydrotestosterone examined by ultrasensitive LC-MS/MS as a predictor of benign prostatic hyperplasia or Gleason score 6 cancer in men with prostate-specific antigen levels of 3-10 ng/mL

There has been no consensus on the role of serum androgen concentrations in prostate cancer detection in men with prostate-specific antigen levels of 3-10 ng/mL. In this study, testosterone and dihydrotestosterone concentrations in blood were examined by a newly developed method using ultrasensitive liquid chromatography with two serially linked mass spectrometers (LC-MS/MS). We investigated the correlation between serum androgen levels and Gleason scores at biopsy. We analyzed data of 157 men with a total prostate-specific antigen range of 3-10 ng/mL who underwent initial systematic prostate needle biopsy for suspected prostate cancer between April 2000 and July 2003. Peripheral blood testosterone and dihydrotestosterone concentrations were determined by LC-MS/MS. Blood levels of testosterone and dihydrotestosterone were compared with pathological findings by multivariate analyses. Median values of prostate-specific antigen and prostate volume measured by ultrasound were 5.7 ng/mL and 31.4 cm³ , respectively. Benign prostatic hyperplasia was diagnosed in 97 patients (61.8%), and prostate cancer was diagnosed in 60 (38.2%) patients, including 31 (19.7%) patients with a Gleason score of 6 and 29 (18.5%) patients with a Gleason score of 7-10. Median values of testosterone and dihydrotestosterone in blood were 3798.7 and 371.7 pg/mL, respectively. There was a strong correlation between serum testosterone and dihydrotestosterone. In multivariate analysis, age, prostate volume, and serum dihydrotestosterone were significant predictors of benign prostatic hyperplasia or prostate cancer with a Gleason score of 6. The area under the receiver operating characteristics curve for age, prostate volume, and serum dihydrotestosterone were 0.67, 0.67, and 0.67, respectively . We confirmed that high dihydrotestosterone blood levels can predict benign prostatic hyperplasia or prostate cancer with a Gleason score of 6 in men with prostate-specific antigen levels of 3-10 ng/mL.

Extra-adrenal induction of Cyp21a1 ameliorates systemic steroid metabolism in a mouse model of congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) due to steroid 21-hydroxylase (21-OH) deficiency (21-OHD) is an autosomal recessive disorder, in which CYP21A2 mutations or deletions result in underproduction of glucocorticoid and mineralocorticoid, and overproduction of androgens. Patients with CAH are treated with oral steroid supplementation, but optimal control of blood steroid levels remains difficult. Thus, new therapeutic approaches are still needed. Previously, adenovirus-mediated administration of human CYP21A2 to adrenal glands rescued the phenotype of a mouse model of 21-OHD. In this study, we examined whether transduction of murine Cyp21a1 in extra-adrenal tissues could rescue steroid metabolism in 21-OHD mice. We transduced primary fibroblasts obtained from 21-OHD mice with a retroviral vector containing Cyp21a1. In vitro assays demonstrated that Cyp21a1-expressing fibroblasts can uptake progesterone from the culture media, convert it to deoxycorticosterone (DOC), and subsequently release DOC back into the media. Autotransplantation of Cyp21a1-expressing fibroblasts into the subcutaneous tissues of the back resulted in a significant reduction in the serum progesterone/DOC ratio in four of six 21-OHD mice at 4 weeks after injection. We also directly injected an adeno-associated viral vector containing Cyp21a1 into the thigh muscles of 21-OHD mice. Serum progesterone/DOC ratios were markedly reduced in all four animals at 4 weeks after injection. These results indicate that extra-adrenal induction of Cyp21a1 ameliorates steroid metabolism in 21-OHD mice. This study suggests a novel therapeutic strategy for congenital adrenal hyperplasia, which warrants further investigations.

Chemical derivatization for enhancing sensitivity during LC/ESI-MS/MS quantification of steroids in biological samples: a review

Sensitive and specific methods for the detection, characterization and quantification of endogenous steroids in body fluids or tissues are necessary for the diagnosis, pathological analysis and treatment of many diseases. Recently, liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) has been widely used for these purposes due to its specificity and versatility. However, the ESI efficiency and fragmentation behavior of some steroids are poor, which lead to a low sensitivity. Chemical derivatization is one of the most effective methods to improve the detection characteristics of steroids in ESI-MS/MS. Based on this background, this article reviews the recent advances in chemical derivatization for the trace quantification of steroids in biological samples by LC/ESI-MS/MS. The derivatization in ESI-MS/MS is based on tagging a proton-affinitive or permanently charged moiety on the target steroid. Introduction/formation of a fragmentable moiety suitable for the selected reaction monitoring by the derivatization also enhances the sensitivity. The stable isotope-coded derivatization procedures for the steroid analysis are also described.

Sensitive determination of cholesterol and its metabolic steroid hormones by UHPLC-MS/MS via derivatization coupled with dual ultrasonic-assisted dispersive liquid-liquid microextraction

RATIONALE

Quantitative analysis of cholesterol and its metabolic steroid hormones plays a vital role in diagnosing endocrine disorders and understanding disease progression, as well as in clinical medicine studies. Because of their extremely low abundance in body fluids, it remains a challenging task to develop a sensitive detection method.

METHODS

A hyphenated technique of dual ultrasonic-assisted dispersive liquid-liquid microextraction (dual-UADLLME) coupled with microwave-assisted derivatization (MAD) was proposed for cleansing, enrichment and sensitivity enhancement. 4'-Carboxy-substituted rosamine (CSR) was synthesized and used as derivatization reagent. An ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed for determination of cholesterol and its metabolic steroid hormones in the multiple reaction monitoring mode.

RESULTS

Parameters of dual-UADLLME, MAD and UHPLC-MS/MS were all optimized. Satisfactory linearity, recovery, repeatability, accuracy and precision, absence of matrix effect and extremely low limits of detection (LODs, 0.08-0.15 pg mL(-1) ) were achieved.

CONCLUSIONS

Through the combination of dual-UADLLME and MAD, a determination method for cholesterol and its metabolic steroid hormones in human plasma, serum and urine samples was developed and validated with high sensitivity, selectivity, accuracy and perfect matrix effect results. Copyright © 2016 John Wiley & Sons, Ltd.

Two simple cleanup methods combined with LC-MS/MS for quantification of steroid hormones in in vivo and in vitro assays

Measuring both progestagens, androgens, corticosteroids as well as estrogens with a single method makes it possible to investigate the effects of endocrine-disrupting chemicals (EDCs) on the main pathways in the mammalian steroidogenesis. This paper presents two simple methods for the determination of the major steroid hormones in biological matrixes using liquid chromatography tandem mass spectrometry (LC-MS(2)). A novel method was developed for the determination of 14 steroids in the H295R in vitro assay without the need for solid phase extraction (SPE) purification prior to LC-MS(2) analysis. The in vitro assay was validated by exposing H295R cells to prochloraz for inhibiting steroid hormone secretion and by exposing cells to forskolin for inducing steroid hormone secretion. The developed method fulfills the recommendations for the H295R assay suggested by the OECD. Furthermore, a simple off-line SPE methodology was developed for the necessary clean-up of in vivo assays. Samples, such as gonad tissue, plasma and serum, are complex biological matrixes, and the SPE methodology was optimized to remove salts and proteins prior to elution of target analytes. At the same time, lipophilic compounds were retained on the SPE cartridge during elution. This, combined with the multi-steroid LC-MS(2) method, made it possible to determine 10 steroids in male Sprague-Dawley rat gonad tissue. Furthermore, it was possible to quantify 6 steroids in the plasma. In general, the observed concentration of steroid hormones in plasma, testes, and H295R cell medium corresponded well with previous studies. The off-line SPE method was validated using spiked charcoal-stripped serum. Method recovery, accuracy, precision and robustness were all good. Instrument sensitivity was in the range of 55-530 pg/mL (LLOQ).

Inverse association of highly chlorinated dioxin congeners in maternal breast milk with dehydroepiandrosterone levels in three-year-old Vietnamese children

This study aims to evaluate the endocrine-disrupting effect of dioxin congeners on adrenal steroid hormones in mother-child pairs. In our previous study, we found that cortisol and cortisone levels were higher in the blood and the saliva of mothers living in a dioxin hotspot area than in mothers from a non-exposed region in Vietnam. In this follow-up study, we determined the salivary steroid hormone levels in 49 and 55 three-year-old children of these mothers in the hotspot and non-exposed region, respectively. Steroid hormones were determined by liquid chromatography-tandem mass spectrometry, and dioxin in the maternal breast milk was determined by gas chromatography-mass spectrometry. Dioxin levels in the breast milk of mothers from the hotspot (median total toxic equivalents polychlorinated dibenzodioxins/polychlorinated dibenzofurans; (TEQ PCDD/Fs) of 11pg/g lipid) were three to four times higher than those of mothers in the non-exposed region (median TEQ PCDD/Fs of 3.07pg/g lipid). Salivary dehydroepiandrosterone (DHEA) levels in children were found to be significantly lower in the hotspot than in the non-exposed region, while cortisol and cortisone levels were not different between the two regions. Highly chlorinated dioxin congeners, such as octacholorodibenzodioxin (OCDD), 1,2,3,4,6,7,8-heptacholorodibenzodioxin (HpCDD) and 1,2,3,4 (or 6), 7,8-hexachlorodibenzodioxin Hx(CDD), showed stronger inverse associations with the children's salivary DHEA than other lowly chlorinated dioxin congeners. Glucocorticoid levels in the mothers exhibited a significantly positive correlation with OCDD and HpCDD/F (polychlorinated dibenzofurans). In conclusion, highly chlorinated dioxin congeners are more strongly correlated with endocrine-disrupting effects on adrenal hormones, resulting in high cortisol levels in the mothers and low DHEA levels in their three-year-old children.

Derivatization of steroids in biological samples for GC–MS and LC–MS analyses

The determination of steroids in biological samples is essential in different areas of knowledge. MS combined with either GC or LC is considered the best analytical technique for specific and sensitive determinations. However, due to the physicochemical properties of some steroids, and the low concentrations found in biological samples, the formation of a derivative prior to their analysis is required. In GC–MS determinations, derivatization is needed for generating volatile and thermally stable compounds. The improvement in terms of stability and chromatographic retention are the main reasons for selecting the derivatization agent. On the other hand, derivatization is not compulsory in LC–MS analyses and the derivatization is typically used for improving the ionization and therefore the overall sensitivity achieved.

Current status and recent advantages in derivatization procedures in human doping control

Derivatization is one of the most important steps during sample preparation in doping control analysis. Its main purpose is the enhancement of chromatographic separation and mass spectrometric detection of analytes in the full range of laboratory doping control activities. Its application is shown to broaden the detectable range of compounds, even in LC–MS analysis, where derivatization is not a prerequisite. The impact of derivatization initiates from the stage of the metabolic studies of doping agents up to the discovery of doping markers, by inclusion of the screening and confirmation procedures of prohibited substances in athlete's urine samples. Derivatization renders an unlimited number of opportunities to advanced analyte detection.

Surrogate matrix: opportunities and challenges for tissue sample analysis

Often there is limited availability of matching tissue matrix and/or the analyte may occur endogenously in the target tissue. Surrogate matrix provides an option for quantitation of drug, metabolite(s) and biomarker(s) in these circumstances. However, the use of a surrogate matrix also presents challenges. This paper summarizes and discusses the challenges of selecting a proper surrogate, validating the suitability of the surrogate and establishing a surrogate tissue method using the fit-for-purpose approach. This paper also systematically reviews the current practices for evaluating key parameters of a surrogate tissue assay, including sensitivity, specificity, selectivity, interference, precision, accuracy, recovery, matrix effects and stability. Considerations and suggestions are provided for dealing with such challenges during method establishment and tissue sample analysis.

Accurate and sensitive liquid chromatography/tandem mass spectrometry simultaneous assay of seven steroids in monkey brain

BACKGROUND

Following its secretion mainly by the adrenal glands, dehydroepiandrosterone (DHEA) acts primarily in the cells/tissues which express the enzymes catalyzing its intracellular conversion into sex steroids by the mechanisms of intracrinology. Although reliable assays of endogenous serum steroids are now available using mass spectrometry (MS)-based technology, sample preparation from tissue matrices remains a challenge. This is especially the case with high lipid-containing tissues such as the brain. With the combination of a UPLC system with a sensitive tandem MS, it is now possible to measure endogenous unconjugated steroids in monkey brain tissue.

METHODS

A Shimadzu UPLC LC-30AD system coupled to a tandem MS AB Sciex Qtrap 6500 system was used.

RESULTS

The lower limits of quantifications are achieved at 250 pg/mL for DHEA, 200 pg/mL for 5-androstenediol (5-diol), 12 pg/mL for androstenedione (4-dione), 50 pg/mL for testosterone (Testo), 10 pg/mL for dihydrotestosterone (DHT), 4 pg/mL for estrone (E1) and 1 pg/mL for estradiol (E2). The linearity and accuracy of quality controls (QCs) and endogenous quality controls (EndoQCs) are according to the guidelines of the regulatory agencies for all seven compounds.

CONCLUSION

We describe a highly sensitive, specific and robust LC-MS/MS method for the simultaneous measurement of seven unconjugated steroids in monkey brain tissue. The single and small amount of sample required using a relatively simple preparation method should be useful for steroid assays in various peripheral tissues and thus help analysis of the role of locally-made sex steroids in the regulation of specific physiological functions.

Effects of the 5α-reductase inhibitor dutasteride on rat prostate α1A-adrenergic receptor and its mediated contractility

OBJECTIVE

To clarify the possible interference of the 5α-reductase inhibitor dutasteride with α-adrenergic blockers, whose action is mainly mediated by α1A-adrenergic receptor.

METHODS

Male rats were divided into dutasteride and vehicle-treated groups. The drug treatment group was treated with oral dutasteride 0.5 mg/kg/d, and the control group received vehicle only for 2 months. After the 2-month treatment, the rats' ventral prostate weight changes and the testosterone and dihydrotestosterone levels in the serum were measured. In vitro organ-bath studies, real-time polymerase chain reaction, and tissue-segment binding were performed to determine the expression of α1A-adrenergic receptors and its mediated contractility.

RESULTS

Dutasteride treatment significantly decreased the rats' ventral prostate weight, increased their testosterone levels, and decreased the dihydrotestosterone levels in their serum. There were no marked changes in the α1A-adrenergic receptor messenger ribonucleic acid expression, relative phenylephrine-induced contractility, or nerve-mediated contractility between the groups. Dutasteride treatment caused no marked changes in the relative binding capacity of α1A-adrenergic receptor, whereas it greatly decreased the total protein expression of this subtype and its mediated maximal contraction in the whole ventral prostate.

CONCLUSION

These results suggest that dutasteride does not interfere with α-adrenergic blockers but otherwise has beneficial effects on their actions. Therefore, the long-term administration of the combination of dutasteride with an α-adrenergic blocker might be a better choice for the treatment of lower urinary tract symptoms due to benign prostatic hyperplasia.