Liquid chromatography quadrupole linear ion trap mass spectrometry for quantitative steroid hormone analysis in plasma, urine, saliva and hair

Determination of cortisol in hair using UHPLC-MS/MS: application to patients admitted for ethanol dependence treatment

Aim: Cortisol hair levels can be used to evaluate chronic stress status. In this context, an improved UHPLC-MS/MS assay for the determination of cortisol in hair was developed and validated. Materials & methods: Hair was extracted with methanol for 4 h at 25°C. Chromatographic run time was 5.5 min. The assay was linear in the range of 1-250 pg mg-1. Precision was 3.6-12.2% and accuracy 97.1-103.8%. The method was applied in hair from 19 volunteers admitted at a rehabilitation clinic, with ethanol consumption classified using ethyl glucuronide hair levels. Conclusion: Abstinent/chronic moderate ethanol consumers had significantly lower cortisol hair levels than chronic excessive consumers. This is the first study evaluating cortisol hair levels in ethanol abuse patients using an objective marker for ethanol consumption.

Comparative analysis of the effects of collection methods on salivary steroids

BACKGROUND

Steroid hormone test for saliva was a promising area of research, however the impact of different collection methods on salivary steroids was underexplored so far. This study was designed to compare the effects of different collection methods (unstimulated or stimulated by chewing paraffin, forepart or midstream) on salivary flow rate, concentrations and secretion rates of steroids in saliva.

METHODS

Whole-saliva samples were collected from 10 systemically and orally healthy participants, whose forepart and midstream segments of saliva were collected under unstimulated and stimulated conditions, with the salivary flow rate of each sample recorded. The concentrations and secretion rates of salivary steroids including testosterone, dehydroepiandrosterone (DHEA) and progesterone were measured by ELISA, with the multiple of change calculated.

RESULTS

The results indicated mechanical stimulation used in collection of saliva samples could affect concentrations and secretion rates of steroids, whereas forepart and midstream segments had little differences in levels of salivary steroids, which effects could be partly influenced by individual specificity. The asynchronism in change of secretion rate of steroids with that of salivary flow rate might play an important role during this course.

CONCLUSION

Based on these findings, we suggested to use the same collection method throughout one analytical study on salivary steroids or in longitudinal observations to ensure the comparability of the saliva samples collected.

Determination of cortisol in hair using liquid chromatography-tandem mass spectrometry: a short review

Cortisol is considered a particularly relevant biomarker in the context of stress evaluation. This study aims to review of the available literature on the determination of cortisol in hair using LC-MS/MS. Currently, there is no standardized procedure for the measurement of cortisol concentrations in hair, and different sample preparation, chromatographic separation and mass spectrometric detection conditions were described. Simple methanolic extraction, reversed-phase separation and MRM detection in negative ion mode are the most common employed analytical approaches. Reported assays presented acceptable sensitivity for clinical purposes. The increasing use of mass spectrometry in clinical laboratories may contribute to the establishment of LC-MS/MS as the method of choice for the determination of cortisol concentrations in hair.

Sample Preparation and Analytical Methods for Steroid Hormones in Environmental and Food Samples: An Update Since 2012

Steroid hormones (SHs) have been widely used over the past few decades as both human and veterinary drugs to prevent or treat infectious diseases and anti-inflammatory benefits in clinical. Unfortunately, their residues in foodstuffs and environmental samples can produce adverse effects on human and animal life such as disrupting the endocrine system. For these reasons, sensitive, simple and efficient methods have been developed for the determination of these compounds in various matrices. This critical review summarized the articles published in the period from 2012 to 2019 and can be used to help researchers to understand development of the sample pretreatment protocols and analytical methods used to detect SHs. The developed extraction and purification techniques used for steroids in different samples, such as cloud point extraction, solid phase extraction based on different novel materials, microextraction methods, QuEChERS and other methods are summarized and discussed. Analytical methods used to quantify these compounds, such as different chromatography methods, electrochemical methods, as well as other methods, are illustrated and compared. We focused on the latest advances in SHs pretreatment, and the application of new technologies in SHs analysis.

Internalized weight bias and cortisol reactivity to social stress

Weight-associated stigmatization and discrimination may induce chronic stress in individuals with obesity. As a consequence, this stressor may cause an imbalance of HPA stress axis leading to increased eating behavior, and ultimately, weight gain. However, the direct link between internalized weight bias and stress response to acute stressors via cortisol secretion has not been investigated so far. Therefore, the purpose of this study was to investigate the interaction between internalized weight stigma as a stressor and cortisol reactivity in an acute psychosocial stress situation induced by the Trier Socials Stress Test for groups (TSST-G). Participants with BMI >30 kg/m² (n = 79) were included in the study. Results reveal that while individuals with low internalized stigma reacted as predicted with an increase in cortisol secretion to acute psychosocial stress, individuals with medium or high internalized stigma did not show a typical cortisol response. However, these findings depend on the several factors, for instance on gender. In sum, acute stress in individuals with internalized weight bias seems to blunt HPA axis reactions to acute psychosocial stress. The study contributes to the understanding of the psychological and endocrinological consequences of internalized weight bias and underlines the importance of interventions to reduce stigmatization.

Breast Cancer: Targeting of Steroid Hormones in Cancerogenesis and Diagnostics

Breast cancer is the most common malignancy in women with high mortality. Sensitive and specific methods for the detection, characterization and quantification of endogenous steroids in body fluids or tissues are needed for the diagnosis, treatment and prognosis of breast cancer and many other diseases. At present, non-invasive diagnostic methods are gaining more and more prominence, which enable a relatively fast and painless way of detecting many diseases. Metabolomics is a promising analytical method, the principle of which is the study and analysis of metabolites in biological material. It represents a comprehensive non-invasive diagnosis, which has a high potential for use in the diagnosis and prognosis of cancers, including breast cancer. This short review focuses on the targeted metabolomics of steroid hormones, which play an important role in the development and classification of breast cancer. The most commonly used diagnostic tool is the chromatographic method with mass spectrometry detection, which can simultaneously determine several steroid hormones and metabolites in one sample. This analytical procedure has a high potential in effective diagnosis of steroidogenesis disorders. Due to the association between steroidogenesis and breast cancer progression, steroid profiling is an important tool, as well as in monitoring disease progression, improving prognosis, and minimizing recurrence.

Liquid chromatography-tandem mass spectrometry measurement of 26 steroid hormones in human serum and plasma samples

The measurement of steroid hormones provided critical information in the clinical evaluation of endocrine disorders. In this study, we developed a high-throughput solid-phase extraction method for the analysis of 26 steroids in human serum and plasma samples by liquid chromatography-tandem mass spectrometry. Chromatographic conditions and sample preparation were optimized to achieve good separation and maximum sensitivity for these analytes. Under the optimum conditions, good linearities were achieved in the quantitative range for each steroid hormone with the correlation coefficients (r) larger than 0.99. The limits of quantitation of the method were in the range from 0.0005 to 0.7901 ng/mL. The recoveries were in the range of 87.2-114.2% with intra- and interday precision lower than 9.94%. This method has already been applied to series of samples from clinical trials, and there was no significant difference between serum and ethylenediaminetetraacetic acid plasma samples.

Development and validation of a sensitive LC-MS/MS method for simultaneous quantification of thirteen steroid hormones in human serum and its application to the study of type 2 diabetes mellitus

Endogenous steroid hormones with similar structure, poor content and high efficacy are difficult and vital to be quantitatively detected. In this study, a validated method was established for the simultaneous quantification of thirteen steroids in human serum, and applied to the study of type 2 diabetes mellitus (T2DM). An ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of thirteen steroid hormones in human serum, including androstenedione, corticosterone (B), cortisol (F), cortisone, 18-hydroxycortisol (18OHF), 11-deoxycorticosterone, 11-deoxycortisol, pregnenolone, progesterone, 17-hydroxyprogesterone, testosterone, androstanolone and estradiol. Under the optimum conditions, method was achieved with a BEH Shield RP18 column within 18 min. The lower limits of quantitation for steroids were 0.08-7.81 ng/mL. The intra- and inter-day precision for all the analytes were less than 15 %, and the accuracy ranged from -14.19 % to 12.89 % at three quality control levels. The proposed method, indicating high steady and sensitivity, was successfully applied to the quantification of thirteen steroids levels in serum from patients with T2DM and healthy individuals. The serum concentrations of 18OHF and F were significantly increased in the patients compared with the healthy individuals, while B was significantly decreased. The fold change was 1.98, 1.25 and 0.79 respectively. The ratio of 18OHF to B (18OHF/B) exhibited a 2.51-fold increase in T2DM patients and presented a more significant change. 18OHF/B was identified as a prospective serum marker, which deserves further attention.

Magnetic Micro-Solid-Phase Extraction Using a Novel Carbon-Based Composite Coupled with HPLC-MS/MS for Steroid Multiclass Determination in Human Plasma

A micron-sized sorbent, Magn-Humic, has been prepared by humic acids pyrolysis onto silica-coated magnetite. The material was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and Brunauer, Emmett, and Teller (BET) surface area measurements and applied for simultaneous magnetic solid-phase extraction (MSPE) of glucocorticoids, estrogens, progestogens, and androgens at ng mL⁻¹ levels from human plasma followed by high-performance liquid chromatography coupled with mass spectrometry (HPLC–MS/MS). Due to the low affinity for proteins, steroids extraction was done with no need for proteins precipitation/centrifugation. As highlighted by a design of experiments, MSPE was performed on 250 µL plasma (after 1:4 dilution) by 50 mg Magn-Humic (reusable for eight extractions) achieving quantitative recovery and satisfying clean-up. This was improved by washing (2 mL 2% v/v formic acid) prior to analytes elution by 0.5 mL 1:1 v/v methanol-acetonitrile followed by 0.5 mL methanol; eluate reduction to 0.25 mL compensated the initial sample dilution. The accuracy was assessed in certified blank fetal bovine serum and in human plasma, gaining satisfactory recovery in the range 65–122%, detection limits in the range 0.02–0.3 ng mL⁻¹ (0.8 ng mL⁻¹ for 17-β-estradiol) and suitable inter-day precision (relative standard deviation (RSD) <14%, n = 3). The method was evaluated in terms of selectivity, sensitivity, matrix-effect, instrumental carry-over, and it was applied to human plasma samples.

From a single steroid to the steroidome: Trends and analytical challenges

For several decades now, the analysis of steroids has been a key tool in the diagnosis and monitoring of numerous endocrine pathologies. Thus, the available methods used to analyze steroids in biological samples have dramatically evolved over time following the rapid pace of technology and scientific knowledge. This review aims to synthetize the advances in steroids' analysis, from classical approaches considering only a few steroids or a limited number of steroid ratios, up to the new steroid profiling strategies (steroidomics) monitoring large sets of steroids in biological matrices. In this context, the use of liquid chromatography coupled to mass spectrometry has emerged as the technique of choice for the simultaneous determination of a high number of steroids, including phase II metabolites, due to its sensitivity and robustness. However, the large dynamic range to be covered, the low natural abundance of some key steroids, the selectivity of the analytical methods, the extraction protocols, and the steroid ionization remain some of the current challenges in steroid analysis. This review provides an overview of the different analytical workflows available depending on the number of steroids under study. Special emphasis is given to sample treatment, acquisition strategy, data processing, steroid identification and quantification using LC-MS approaches. This work also outlines how the availability of steroid standards, the need for complementary analytical strategies and the improvement of calibration approaches are crucial for achieving complete steroidome quantification.

Determination of testosterone in serum and saliva by liquid chromatography-tandem mass spectrometry: An accurate and sensitive method applied on clinical and forensic samples

A highly sensitive and accurate electrospray liquid chromatography tandem-mass spectrometry (ESI-LC-MS/MS) method for determination of testosterone in human serum and saliva was developed and validated. Accurate quantification of testosterone in human matrices is essential in diagnosis and management of androgen status in men, women and children, and in forensic investigations of suspected abuse of anabolic androgenic steroids. Chromatography was performed on an HSS-T3 C18 column with a total run-time of 5.5 min. The tandem mass spectrometry was operated in positive electrospray ionization mode with multiple reaction monitoring. Serum and saliva samples of 200 μL, were prepared by solid-phase extraction using a 96-well plate following precipitation with 200 μL methanol. ¹³C labeled testosterone was used as internal standard for quantification. The standard curve was linear within the range of 4-1000 pg/mL and the limit of quantification of both serum and salivary testosterone was 4 pg/mL. Accuracy were 99-101 % and 93-95 % with between-run imprecision in serum and saliva, respectively, and inter- and intra-assay coefficients of variation were less than 9.2 %. The method proved to be applicable for determination of testosterone over a wide range of concentrations in serum and saliva samples from clinical patients with various androgen disorders, healthy male and female adults as well as from forensic cases.

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.

Quantification of steroid hormones in human urine by DLLME and UHPLC-HRMS detection

A procedure for the quantification of steroid hormones of various classes in human urine (androgens, estrogens, progestins, corticosteroids) has been described consisting of sample preparation by means of dispersive liquid-liquid extraction after enzymatic hydrolysis with β-glucuronidase from E. Coli followed by ultra-high performance liquid chromatography-high resolution mass spectrometry (quadrupole time-of-flight) detection. Both one-variable-at-a-time and multivariate approaches (full factorial and Box-Behnken designs) were applied to optimize sample preparation conditions. The procedure was validated using synthetic urine in the concentration range of 0.25-500 ng/mL. Then, it was applied to the analysis of real urine samples and the results were compared with those of a common liquid-liquid extraction procedure. The results obtained proved its applicability to the quantification of steroid hormones in human urine with high sensitivity and accuracy.

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.

Current methods for stress marker detection in saliva

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Introduction of relevant biomarkers in stress conditions.

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Reference ranges of biomarkers in normal conditions.

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Saliva as easy-accessible specimen.

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Review of analytical methods for biomarker determination in saliva.

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Possibilities for design of point-of-care devices.

Stress and stress-related diseases are leading to drastic consequences in private and professional life. Therefore, the need for stress prevention strategies is of personal and economic interest. Especially during the recent period related to covid-19 outbreak and lock-down, an ongoing discussion of increasing stress etiology is reported. Biomarker analysis may help to assist diagnosis and classification of stress-related diseases and therefore support therapeutical decisions. Due to its non-invasive sampling, the analysis of saliva has become highly attractive compared to the detection methods in other specimen. This review article summarizes the status of research, innovative approaches, and trends. Scientific literature published since 2011 was excerpted with concentration on the detection of up to seven promising marker substances. Most often reported cortisol represents the currently best evaluated stress marker, while norepinephrine (noradrenaline) or its metabolite 3-methoxy-4-hydroxyphenylglycol is also a quite commonly considered stress marker. Other complementary stress marker candidates are testosterone, dehydroepiandrosterone (DHEA) and its sulfonated analogue DHEA-S, alpha-amylase, secretory immunoglobulin A, and chromogranin A. Several working groups are researching in the field of stress marker detection to develop reliable, fast, and affordable methods. Analytical methods reported mainly focused on immunological and electrochemical as well as chromatographic methods hyphenated to mass spectrometric detection to yield the required detection limits.

HA-C@silica sorbent for simultaneous extraction and clean-up of steroids in human plasma followed by HPLC-MS/MS multiclass determination

Aim and novelty of this work are the development of a simple and straightforward analytical procedure for multiclass determination of steroid hormones in human plasma. The method entails a single pre-treatment step based on solid-phase extraction using a recently proposed sorbent phase (HA-C@silica). This is easily prepared with good reproducibility via pyrolysis of humic acids onto silica, and not yet tested in biological fluids. It proved to be advantageous as it showed poor affinity for the protein matrix constituents while quantitatively extracting and pre-concentrating the target analytes. Indeed, as demonstrated in bovine serum albumin solution, up to ca. 90% protein is not retained by the sorbent, similarly to the behaviour of restricted access carbon nanotubes, tested for comparison. The high albumin exclusion allowed a satisfactory clean-up avoiding protein precipitation and centrifugation before extraction. The extraction procedure, optimized by a chemometric approach (2³ experimental design) in BSA solution, provided quantitative recovery (76-119%, n = 3) for all steroids working with 1:8-diluted plasma (2 mL) and 100 mg HA-C@silica. Before analytes elution by 1 mL methanol-acetonitrile (1:1, v/v), selective washings (2% v/v formic acid and 30% v/v methanol) were applied to remove the small fraction of retained proteins, thus obtaining very clean SPE extracts to be analyzed by HPLC-ESI-MS/MS. This allowed identification/quantification (MRM mode) at few ng mL^-1 by a single chromatographic run. The procedure was verified in blank-certified foetal bovine serum (spikes 10-100 ng mL^-1), obtaining good recovery and suitable inter-day precision (RSDs < 15%, n = 3). The analytical method, applied to real plasma samples analysis, is appealing in terms of sample throughput, extraction efficiency and clean-up.

Hair Cortisol Concentration in Healthy Children and Adolescents Is Related to Puberty, Age, Gender, and Body Mass Index

INTRODUCTION

Hair cortisol concentrations (HCC) have been found to be related to various common childhood diseases, like otitis media, conjunctivitis, respiratory viral infections, and asthma. However, the confounding effects of age, gender, body mass index (BMI), pubertal stage (Tanner stages), socioeconomic status (SES) as well as of some hair maintenance procedures on HCC are still not well examined.

METHODS

A population-based cohort of 434 children aged between 5 and 18 years was examined for HCC between January 2012 and February 2015 in the context of the Leipzig Research Centre for Civilization Diseases (LIFE) Child study. Thereby, anthropometric data, gender, BMI, SES and pubertal status were assessed. HCC was measured by liquid chromatography mass spectrometry.

RESULTS

In the total cohort, HCC levels ranged between 0.95 and 29.86 pg/mg. In prepuberty, boys showed significantly higher HCC than girls (6.54 vs. 3.73 pg/mg, p < 0.05). During puberty HCC values in both genders converged. Higher BMI was significantly associated with higher HCC in both genders. In girls, HCC did not differ depending on Tanner stages. In boys, HCC was significantly higher in Tanner stage 1 than in stages 2-5.

CONCLUSION

Measuring cortisol concentration in hair gives information about long-term release of cortisol. We have found that puberty, gender, and BMI had a profound effect on HCC. As a result, further research should take into account the potentially confounding role of puberty, gender and BMI and may use the results of our study as a reference at determining values of HCC in healthy children.

Determination of steroid profile in hair by liquid chromatography tandem mass spectrometry

The simultaneous determination of a large number of steroids (a.k.a. steroid profile) is a powerful tool that provides useful information about the status of steroid hormones. Steroid profile evaluated in matrices such as urine, saliva and plasma provide one-off moment information about the hormonal status and is highly affected by different factors such as circadian rhythm or apprehension to needles. In contrast, the determination of the steroid profile in hair would provide information about the chronic status of the steroid hormones. The objective of the current research was to develop and validate a liquid chromatography-tandem mass spectrometry (LC-MS/MS) methodology for the determination of 11 steroids in hair, including 6 hormones and 5 metabolites. We have optimized different parts of the analytical procedure such as (i) hair shredding, (ii) hair amount, (iii) extraction from hair, (iv) extraction time, (v) required extractions and (vi) analytes preconcentration. MS parameters such as the inclusion of ESI- transitions were also evaluated. The optimization of these parameters was found to be critical to achieve the required sensitivity for the determination of steroids in hair. The method was validated with appropriate linearity in the endogenous range, intra- and inter-assay accuracies and matrix effect between 80% and 120% and intra- and inter-assay precisions below 20% for all analytes. Most of the analytes showed to be stable up to 10 months at room temperature. The suitability of the method was evaluated by obtaining the endogenous concentration range of steroids in 30 healthy volunteers. Results agreed with the scarce data previously reported for some steroids. For others, endogenous concentration ranges in hair were reported for the first time. Additionally, the method was used to compare intraindividual levels of steroids in beard and hair. Results revealed that with the exception of testosterone, beard is a suitable alternative to the hair determination of the steroid profile. In summary, the present strategy to evaluate the steroid profile in hair may be a useful tool with a high potential for a wide range of clinical purposes.

An isotope dilution LC–MS/MS-based candidate reference method for the quantification of androstenedione in human serum and plasma

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LC-MS/MS-based candidate reference method for the quantification of androstenedione.

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Certified reference material from NMIA with additional qNMR characterization.

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Uncertainty evaluation according to the GUM 1995.

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Inter laboratory comparison study and comparison to a routine LC-MS/MS assay.

The accurate measurement of androstenedione in human serum and plasma is required for steroid profiling to assure the appropriate diagnosis and differential diagnosis of hyperandrogenism. In this work, we introduce an isotope dilution liquid chromatography–tandem mass spectrometry (LC–MS/MS) candidate reference measurement procedure for the quantification of androstenedione in human serum and plasma. The performance of the procedure enables its use in the evaluation and standardization of routine assays and for the evaluation of patient samples to ensure the traceability of individual patient results. As the primary standard, a certified reference material from NMIA (National Measurement Institute, Australia) was used. Additionally, a quantitative nuclear magnetic resonance (qNMR) method was developed for the value assignment of the primary reference material, which ensures the direct traceability to SI units, as well as the independence from the availability of reference materials. ¹³C₃-labeled androstenedione was used as the internal standard. The introduced method allows the measurement of androstenedione in the range of 0.05–12 ng/mL, and the assay imprecision was found to be <2% between 5 and 12 ng/mL, 3.5% at 1.5 ng/mL, and 5.2% at 0.05 ng/mL, with an accuracy of 95–105% for the serum and 91–103% for the plasma matrix. The transferability to a second laboratory was validated by method comparison based on 112 patient samples. The comparison of the results obtained from the presented method and an LC–MS/MS routine assay, using 150 native patient samples, showed a good correlation with a bias of the routine method of ≤4.0%.

Female and male serum reference intervals for challenging sex and precursor steroids by liquid chromatography - tandem mass spectrometry

Measuring some sex and precursor steroids is still challenging even by liquid chromatography - tandem mass spectrometry (LC-MS/MS), and few normal values are available. We developed a LC-MS/MS method for estradiol, estrone, dihydrotestosterone and 17-hydroxypregnenolone measurement, compared it with direct immunoassays, and generated sex, age, menopausal and menstrual status specific reference intervals. Liquid-liquid extraction was optimized on 300 μL serum spiked with isotopic internal standards. A 2D-LC system allowed on-line purification and separation in 11 min run. Electrospray ionization was enhanced by ammonium fluoride. MS-detection was obtained by multiple reaction monitoring. Direct ECLIA for estradiol (n = 80) and RIA for estrone (n = 41) were compared with LC-MS/MS. Reference values were estimated in healthy, lean women in reproductive age (n = 118), menopausal women (n = 33) and men (n = 159). The assay showed satisfying imprecision, trueness, recovery and selectivity. Adequate functional sensitivity was achieved for measuring estrone (18.1 pmol/L) and 17-hydroxypregnenolone (117 pmol/L) in all subjects, and estradiol (35.9 pmol/L) and dihydrotestosterone (134 pmol/L) in women in reproductive age and men, but not in menopausal women. Compared with LC-MS/MS, immunoassays showed good agreement for estradiol but severe disagreement for estrone. Estrogens exhibited sex, menopausal and menstrual variations. Dihydrotestosterone and 17-hydroxypregnenolone depended on sex and menopause, the latter also declining with age in men. Strictly defined reference intervals in the adult female and male population were generated for challenging steroids such as estrogens, dihydrotestosterone and 17-hydroxypregnenolone by a novel LC-MS/MS method. Our achievement can be used to deepen the comprehension of several endocrine diseases.

Sex-specific Estrogen Levels and Reference Intervals from Infancy to Late Adulthood Determined by LC-MS/MS

CONTEXT

The lack of sensitive and robust analytical methods has hindered the reliable quantification of estrogen metabolites in subjects with low concentrations.

OBJECTIVE

To establish sex-specific reference ranges for estrone (E1) and estradiol (E2) throughout life and to evaluate sex-differences using the state-of-the-art liquid chromatography tandem mass spectrometry (LC-MS/MS) method for quantification of E1, E2, and estriol (E3).

DESIGN

LC-MS/MS method development and construction of estrogen reference ranges.

SETTINGS

Population-based cross-sectional cohorts from the greater Copenhagen and Aarhus areas.

PARTICIPANTS

Healthy participants aged 3 months to 61 years (n = 1838).

RESULTS

An isotope diluted LC-MS/MS method was developed and validated for measurements of serum E1, E2, and E3. Limits of detections (LODs) were 3 pmol/L (E1), 4 pmol/L (E2), and 12 pmol/L (E3), respectively. This sensitive method made it possible to differentiate between male and female concentration levels of E1 and E2 in children. In girls, E2 levels ranged from

CONCLUSION

Reference ranges of simultaneous quantification of E1 and E2 by this novel specific and highly sensitive LC-MS/MS method provide an invaluable tool in clinical practice and in future research studies.

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Key Words

• LC-MS/MS
• childhood
• estradiol
• estrone
• menopause
• menstrual cycle
• mini-puberty
• pubertal development
• reference range

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MESH Headings

• Adolescent
• Adult
• Child
• Child, Preschool
• Chromatography, Liquid/methods
• Chromatography, Liquid/statistics & numerical data
• Estradiol/blood
• Estrone/blood
• Female
• Healthy Volunteers
• Humans
• Infant
• Male
• Middle Aged
• Reference Values
• Sensitivity and Specificity
• Sex Factors
• Tandem Mass Spectrometry/methods
• Tandem Mass Spectrometry/statistics & numerical data
• Young Adult

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Grants

• Innovation Fund Denmark
• ReproUnion collaboration

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Affiliation(s)

Hanne Frederiksen Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark
Trine Holm Johannsen Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark
Stine Ehlern Andersen Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
Jakob Albrethsen Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark
Selma Kløve Landersoe The Fertility Clinic, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
Jørgen Holm Petersen Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark Department of Biostatistics, University of Copenhagen, Copenhagen, Denmark
Anders Nyboe Andersen The Fertility Clinic, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
Esben Thyssen Vestergaard Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aahus, Denmark
Mia Elbek Schorring Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aahus, Denmark
Allan Linneberg Center for Clinical Research and Disease Prevention, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
Katharina M Main Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark
Anna-Maria Andersson Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark
Anders Juul Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), University of Copenhagen, Copenhagen, Denmark

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A liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based assay to profile 20 plasma steroids in endocrine disorders

Background

Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based assays are employed in more and more clinical laboratories to quantify steroids. The steroid quantification by LC-MS/MS shows great value in screening or diagnosing endocrine disorders; however, the number of functional steroids included in the LC-MS/MS methods is still limited.

Methods

Here, we describe the performance and validation of a 20-steroid plasma panel by LC-MS/MS. The panel included progestogens (including mineralocorticoids and glucocorticoids), androgens and estrogens biosynthesized in steroid metabolic pathways. The LC-MS/MS method was validated according to guidance documents, and subsequently employed to profile steroid changes in endocrine disorders.

Results

Using LC-MS/MS, 20 steroids were separated and quantified in 8 min. Coefficients of variation (CVs) of the 20 analytes at the lower limit of quantification (LLoQ) were all less than 15% (ranging from 1.84% to 14.96%). The linearity of the assay was demonstrated by all the R2 values greater than 0.995. Individual plasma steroids changed significantly in patients with subclinical Cushing's syndrome (SCS) and polycystic ovary syndrome (PCOS) - 17-hydroxypregnenolone (17-OH-PR), testosterone (T) and dihydrotestosterone (DHT) were significantly decreased in SCS patients, while in PCOS patients, pregnenolone, corticosterone (CORT), androstenedione (A4) and T were significantly increased and DHT was decreased.

Conclusions

The LC-MS/MS method we developed for the quantification of 20 plasma steroids is clinical practicable. The steroid profiling data using this assay indicate its screening value for endocrine disorders. To further explore the value of the assay, more investigations are however needed.

Unraveling the steroid hormone response in male marathon runners: Correlation of running time with aldosterone and progesterone

Marathon running is a physical and psychological stressor. We aimed to characterize the response of nine steroid hormones, which include estradiol, progesterone, testosterone, cortisol, aldosterone, 17-hydroxyprogesterone, cortisone, androstenedione, and dehydroepiandrosterone sulfate, to marathon running and their association with performance. Blood samples of sixty men (age: 49.3 ± 5.9 years) who participated in the Berlin marathon were collected within 3 days before, within 30 min and within 58 h after the end of the marathon. The nine steroid hormones in serum were quantified using liquid chromatography-tandem mass spectrometry. The responses of nine steroid hormones to marathon running were characterized. Aldosterone (fold change: 8.5), progesterone (fold change: 6.6), and cortisol (fold change: 3.7) showed significant increases within 30 min after the marathon (all p < 0.0001). Estradiol but not testosterone increased in the male runners. Marathon running time was significantly related to aldosterone increase (beta=-0.238, p = 0.008) and progesterone increase (beta=-0.192, p = 0.036) in addition to body mass index, self-reported training distance, and age. Serum progesterone correlated with aldosterone and cortisol (r = 0.81 and r = 0.92, respectively, p < 0.001). Progesterone, as a precursor hormone, is increased after the completion of marathon running in association with the increase of aldosterone and cortisol. These findings reveal a contribution of progesterone during the response to the psycho-physical stress of marathon running in males.

Genetic Association Study of Eight Steroid Hormones and Implications for Sexual Dimorphism of Coronary Artery Disease

CONTEXT

Steroid hormones are important regulators of physiological processes in humans and are under genetic control. A link to coronary artery disease (CAD) is supposed.

OBJECTIVE

Our main objective was to identify genetic loci influencing steroid hormone levels. As a secondary aim, we searched for causal effects of steroid hormones on CAD.

DESIGN

We conducted genome-wide meta-association studies for eight steroid hormones: cortisol, dehydroepiandrosterone sulfate (DHEAS), estradiol, and testosterone in two independent cohorts (LIFE-Adult, LIFE-Heart, maximum n = 7667), and progesterone, 17-hydroxyprogesterone, androstenedione, and aldosterone in LIFE-Heart only (maximum n = 2070). All genome-wide significant loci were tested for sex interactions. Furthermore, we tested whether previously reported CAD single-nucleotide polymorphisms were associated with our steroid hormone panel and investigated causal links between hormone levels and CAD status using Mendelian randomization (MR) approaches.

RESULTS

We discovered 15 novel associated loci for 17-hydroxyprogesterone, progesterone, DHEAS, cortisol, androstenedione, and estradiol. Five of these loci relate to genes directly involved in steroid metabolism, that is, CYP21A1, CYP11B1, CYP17A1, STS, and HSD17B12, almost completing the set of steroidogenic enzymes with genetic associations. Sexual dimorphisms were found for seven of the novel loci. Other loci correspond, for example, to the WNT4/β-catenin pathway. MR revealed that cortisol, androstenedione, 17-hydroxyprogesterone, and DHEA-S had causal effects on CAD. We also observed enrichment of cortisol and testosterone associations among known CAD hits.

CONCLUSION

Our study greatly improves insight into genetic regulation of steroid hormones and their dependency on sex. These results could serve as a basis for analyzing sexual dimorphism in other complex diseases.

Reference intervals of nine steroid hormones over the life-span analyzed by LC-MS/MS: Effect of age, gender, puberty, and oral contraceptives

New reference intervals need to be established for a new analytical method with improved sensitivity and specificity. We aimed to establish the new reference intervals from infancy to senescence of nine steroid hormones (cortisol, cortisone, progesterone, 17-hydroxyprogesterone (17-OHP), androstenedione, testosterone, estradiol, DHEAS, and aldosterone) for LC-MS/MS method. Serum samples from 4678 reference individuals (age range: 0.3-79 years) were measured with LC-MS/MS. Samples were collected between 7 a.m. and 10 a.m. Exclusion criteria were concomitant endocrine diseases and body mass index ≥ 33. Generalized additive model for location, scale and shape, the nonparametric or robust method was applied. We established the reference intervals of the nine steroid hormones by sex, age, and pubertal stage. Below the age of one, we observed the surge of androgen and estrogen which implied mini-puberty. At the same period of life, aldosterone and cortisone levels were very high reflecting physiological hyperaldosteronism. An increase of steroid hormones during the pubertal development and slow decrease towards senescence after the peak at early adulthood were observed. Due to the increase of CBG synthesis, cortisol levels were increased under oral contraceptives (OC) significantly (p < 0.0001), while OC suppressed progesterone, 17-OHP, androstenedione, and estradiol (p < 0.0001). Our results will facilitate the interpretation of patient data in routine diagnostics with the use of LC-MS/MS method. Since LC-MS/MS methods have shown good comparability among the different laboratories, our reference intervals can be further adopted in other laboratories equipped with LC-MS/MS, once the validation with a small number of reference samples is performed.

Advancement in steroid hormone analysis by LC-MS/MS in clinical routine diagnostics - A three year recap from serum cortisol to dried blood 17α-hydroxyprogesterone

Steroid analysis by LC-MS/MS in daily clinical routine diagnostics requires high-throughput conditions including fast chromatographic separation. Hereby, signal interferences may occur due to limited specificity in complex biologic matrices. During the last three years of routine steroid analysis in our laboratory and roughly 50,000 measurements, about 1% was affected by interferences, mainly serum cortisol (>90%) and dried blood 17α-hydroxyprogesterone (17-OHP). To overcome specificity problems, enhanced chromatography, ionization polarity switching, and detection via two-stage fragmentation (MS³) using a quadrupole linear ion trap were investigated in our study. Signal interferences of serum cortisol were eliminated by applying a protocol for automated method switching without changing the basic high-throughput LC-MS/MS setup. This approach includes negative ionization and extended chromatography from 4 to 6.6 min using the fourfold column length. From 9 samples affected by cortisol interference using the high-throughput method, 8 could be reliably analyzed applying the method switching protocol. Moreover, the applicability of the high-throughput method as second tier analysis in congenital adrenal hyperplasia (CAH) diagnostics from dried blood was verified with 100% diagnostic specificity. In addition, the combination of fast LC and MS³ detection enables specific quantitation of 17-OHP from dried blood spots on a screening time scale. This approach may be an alternative to the newborn screening for CAH by immunoassay due to its higher specificity, reducing the number of false positive results by 90%. In this work we recap experiences from three years of clinical routine steroid analysis via LC-MS/MS and present a unique analytical setup that enables both high-throughput and enhanced resolution analysis of steroid hormones in serum and dried blood.

Acute psychosocial stress alters thalamic network centrality

Acute stress triggers a broad psychophysiological response that is adaptive if rapidly activated and terminated. While the brain controls the stress response, it is strongly affected by it. Previous research of stress effects on brain activation and connectivity has mainly focused on pre-defined brain regions or networks, potentially missing changes in the rest of the brain. We here investigated how both stress reactivity and stress recovery are reflected in whole-brain network topology and how changes in functional connectivity relate to other stress measures. Healthy young males (n = 67) completed the Trier Social Stress Test or a control task. From 60 min before until 105 min after stress onset, blocks of resting-state fMRI were acquired. Subjective, autonomic, and endocrine measures of the stress response were assessed throughout the experiment. Whole-brain network topology was quantified using Eigenvector centrality (EC) mapping, which detects central hubs of a network. Stress influenced subjective affect, autonomic activity, and endocrine measures. EC differences between groups as well as before and after stress exposure were found in the thalamus, due to widespread connectivity changes in the brain. Stress-driven EC increases in the thalamus were significantly correlated with subjective stress ratings and showed non-significant trends for a correlation with heart rate variability and saliva cortisol. Furthermore, increases in thalamic EC and in saliva cortisol persisted until 105 min after stress onset. We conclude that thalamic areas are central for information processing after stress exposure and may provide an interface for the stress response in the rest of the body and in the mind.

Stress biomarkers in minimally invasive and conventional colorectal resections

INTRODUCTION

Any surgical procedure develops a stress situation for the patient, which can modulate the individual outcome. At present, there is only limited information about stress response in colorectal resections by laparoscopic compared to conventional surgery. Therefore, our objectives were the feasibility and the investigation of stress biomarkers including copeptin and steroid hormones before, during and after colorectal surgery.

METHODS

Eleven patients underwent minimally invasive and ten patients conventionally open colorectal surgery. Blood samples were collected before, during and 24 h after surgery and copeptin, NT-proBNP, cortisol, cortisone, interleukin-6 and glucose were analyzed.

RESULTS

Both, minimally invasive and conventional-open colorectal surgery caused a fast but heterogeneous response of stress biomarkers. However, the postoperative decrease of cortisol, cortisone and glucose differed between both groups. The stress biomarkers decreased faster down to baseline after minimally invasive surgery, while in open surgery cortisol, cortisone and glucose did not return to baseline within 24 h after operation.

CONCLUSIONS

We show in this feasibility study for the first time an increase of copeptin in combination with glucocorticoids as stress biomarkers by open surgery compared to minimally invasive procedures in patients undergoing colorectal surgery. Exceeding an individual threshold of 'stress burden' may have unfavorable effects on the long-time clinical outcome.

Salivary cortisone, as a biomarker for psychosocial stress, is associated with state anxiety and heart rate

BACKGROUND

Stress activates the central nervous, the autonomic nervous, and the endocrine system. This study aimed to (1) test the usability of salivary cortisone in a standardized psychosocial stressor, (2) create a comprehensive profile of hormonal responses to determine laboratory parameters with high discriminatory power, and (3) analyze their association with psychometric and autonomic stress measures.

METHODS

Healthy young men (18-35 years) completed either the Trier Social Stress Test (TSST) (n = 33) or a Placebo-TSST (n = 34). Blood and saliva were collected at 14 time points along with state-anxiety (STAI) and heart rate. Serum steroids (cortisol*, cortisone*, dehydroepiandrosterone-sulfate, androstenedione*, progesterone*, 17-hydroxyprogesterone*, testosterone, estradiol*, aldosterone*), salivary cortisol* and cortisone*, copeptin*, adrenocorticoptropic hormone*, corticosteroid-binding globulin, and salivary alpha-amylase* were analyzed. We used mixed-design ANOVAs to test group differences, receiver operator characteristic (ROC) curve analyses to assess the discriminatory power of each measure, and Spearman correlation analyses to probe the association between measures.

RESULTS

The largest area under the ROC curve was observed in salivary cortisone at 20 min after the end of the TSST (AUC = 0.909 ± 0.044, p < 0.0001). Significant time-by-group interactions were found in the parameters marked with * above, indicating stress-induced increases. The peak response of salivary cortisone was significantly associated with those of STAI (rho = 0.477, p = 0.016) and heart rate (rho = 0.699, p < 0.0001) in the TSST group.

CONCLUSION

Our study found salivary cortisone to be a stress biomarker with high discriminatory power and significant correlations with subjective and autonomic stress measures. Our results can inform future stress studies of sampling time for different laboratory parameters.

Correlation of hair risperidone concentration and serum level among patients with schizophrenia

BACKGROUND

Risperidone (RSP) has a rapid onset in vivo, low dosage and high plasma protein binding rate, therefore therapeutic drug monitoring (TDM) is needed to ensure safety in clinical treatment. However, compared with blood, hair is non-invasive, safe, non-infectious and easy to transport and store.

AIMS

This study aims to investigate the correlations among the drug concentrations of RSP in hair and serum, which provides an experimental basis to explore hair as a novel biomaterial to meet the needs of clinical detection.

METHODS

34 patients with schizophrenia treated with RSP for more than 3 months were enrolled in this study. About 1 cm section of hair near the scalp was taken from the subjects, pretreated and detected by liquid chromatography-mass spectrometry. A correlation analysis was conducted among the drug concentrations in hair, the serum concentrations and the daily dosage. The data were analysed using SPSS 20.0 software.

RESULTS

There was significant correlation between the hair concentration of RSP (two-tailed test, r=0.440, p=0.009) with the serum concentration of RSP, and the hair concentration of 9-hydroxyrisperidone (9-HR) with the serum concentration of 9-HR had no significant correlation (two-tailed test, r=-0.217, p=0.217); the total concentration of the RSP and 9-HR had no significant correlation between hair and serum (r=0.227, p=0.196). The dosage had no statistically significant correlation with the concentration of RSP in hair (r=0.207, p=0.241), 9-HR in hair (r=-0.194, p=0.271) and the total concentration of RSP and 9-HR in hair (r=0.188, p=0.288). There was no statistical correlation between the dosage and the concentration of RSP in serum (r=-0.059, p=0.741), but significant correlation between the dosage and 9-HR in serum (r=0.581 p<0.001) was found, and the correlation between the dosage and the total concentration of the two drugs RSP and 9-HR in serum was also significant (r=0.437, p=0.01).

CONCLUSION

The correlation analysis showed that the concentration of RSP in hair was statistically significant with the serum RSP concentration. In this study, we provided some experimental basis for hair as a new biomaterial to monitor the therapeutic drug concentration.

25-Hydroxyvitamin D Measurement in Human Hair: Results from a Proof-of-Concept study

Vitamin D deficiency has been implicated in numerous human diseases leading to an increased interest in assessing vitamin D status. Consequentially, the number of requests for vitamin D measurement keeps dramatically increasing year-on-year. Currently, the recognised best marker of vitamin D status is the concentration of the 25-hydroxyvitamin D (25(OH)D₃) in the blood circulation. While providing an accurate estimate of vitamin D status at the point in time of sampling, it cannot account for the high variability of 25(OH)D₃ concentration. In this proof of concept study we set out to provide evidence that 25(OH)D₃ can be extracted from hair samples in a similar fashion to steroid hormones. Two of the authors (L.Z. and M.H.) provided hair samples harvested from the crown area of the scalp and the third author (E.L.) provided beard samples. These samples, cut into 1 cm lengths, were weighed, washed and dried. 25(OH)D was extracted using a previously published steroid hormones extraction procedure. Blood samples were taken from the subjects at the same time all tissue samples were analysed using liquid-chromatography mass spectrometry. Hair samples showed presence of quantifiable 25(OH)D₃ with concentrations ranging from 11.9–911 pg/mg. The beard sample had a concentration of 231 pg/mg. Serum levels of 25(OH)D₃ ranged from 72–78 nmol/L. The results presented here confirm the feasibility of measuring 25(OH)D₃ in hair samples. The findings warrant further validation and development and have the potential to yield valuable information relating to temporal trends in vitamin D physiology.

Adaptation and Validation of the Korean Version of the Urticaria Control Test and Its Correlation With Salivary Cortisone

Purpose

Frequent changes in chronic urticaria (CU) activity over time can cause psychological stress, which also serves as a trigger of CU. To measure the control status of CU, the Urticaria Control Test (UCT) was developed in Germany. This study aimed to investigate the validity, reliability and responsiveness to changes in CU for the Korean version of the UCT (K-UCT) and its relation with salivary cortisol and cortisone levels.

Methods

Linguistic adaptation of the UCT into Korean was conducted. A total of 96 CU patients were enrolled, and 80 of them completed the study. The K-UCT and other outcome scores for CU were measured and repeated after 4 weeks of treatment. Control status was classified by physicians into well-controlled, partly-controlled, and uncontrolled CU. Salivary cortisol and cortisone were measured by liquid chromatography-tandem mass spectrometry.

Results

Excellent internal consistency and intra-class reliability were obtained. Strong correlations between the K-UCT and disease severity, reflected in the Urticaria Activity Score (UAS)/global assessment of urticaria control by physicians/patient assessment of symptom severity/CU-specific quality of life were noted. K-UCT scores ≥12 were found to be optimal for determining well-controlled CU (sensitivity, 75.0%; specificity, 758%; area under the curve, 0.824). Perceived stress scale scores were significantly correlated with the UAS and the K-UCT. Salivary cortisone levels were significantly correlated with K-UCT (r = 0.308, P = 0.009) and differed significantly according to control status determined by a K-UCT ≥12.

Conclusions

This study demonstrated that the K-UCT can be a valid instrument with which to gauge CU control status in Korean patients. Further studies are needed to validate salivary cortisone as a biomarker for CU control.

The evolution of methods for urinary steroid metabolomics in clinical investigations particularly in childhood

The metabolites of cortisol, and the intermediates in the pathways from cholesterol to cortisol and the adrenal sex steroids can be analysed in a single separation of steroids by gas chromatography (GC) coupled to MS to give a urinary steroid profile (USP). Steroids individually and in profile are now commonly measured in plasma by liquid chromatography (LC) coupled with MS/MS. The steroid conjugates in urine can be determined after hydrolysis and derivative formation and for the first time without hydrolysis using GC-MS, GC-MS/MS and liquid chromatography with mass spectrometry (LC-MS/MS). The evolution of the technology, practicalities and clinical applications are examined in this review. The patterns and quantities of steroids changes through childhood. Information can be obtained on production rates, from which children with steroid excess and deficiency states can be recognised when presenting with obesity, adrenarche, adrenal suppression, hypertension, adrenal tumours, intersex condition and early puberty, as examples. Genetic defects in steroid production and action can be detected by abnormalities from the GC-MS of steroids in urine. New mechanisms of steroid synthesis and metabolism have been recognised through steroid profiling. GC with tandem mass spectrometry (GC-MS/MS) has been used for the tentative identification of unknown steroids in urine from newborn infants with congenital adrenal hyperplasia. Suggestions are made as to areas for future research and for future applications of steroid profiling. As routine hospital laboratories become more familiar with the problems of chromatographic and MS analysis they can consider steroid profiling in their test repertoire although with LC-MS/MS of urinary steroids this is unlikely to become a routine test because of the availability, cost and purity of the internal standards and the complexity of data interpretation. Steroid profiling with quantitative analysis by mass spectrometry (MS) after chromatography now provides the most versatile of tests of adrenal function in childhood.

The art of measuring steroids: Principles and practice of current hormonal steroid analysis

Steroids are small and highly important structural or signalling molecules in living organisms and their metabolism is complex. Due to the multiplicity of enzymes involved there are many different steroid related disorders. E.g., an individual enzyme defect is rather rare but can share various clinical symptoms and can thus be hardly diagnosed clinically. Therefore, reliable hormonal determination still presents the most reasonable initial diagnostic approach and helps to avoid uncritical and expensive attempts at molecular diagnostic testing. It also presents a backbone of monitoring these complex patients. In science, reliable hormone measurement is indispensable for the elucidation of new mechanisms of steroid hormone actions. Steroid analytics is highly challenging and should never be considered trivial. Most common methods for steroid determination comprise traditionally immunoassay, or more recently, mass spectrometry based methods. It is absolutely necessary that clinicians and scientists know the methods they are applying by heart. With the introduction of automated direct assays, a loss of quality could be observed over the last two decades in the field of steroid immunoassays. This review wants to meet the need for profound information and orientation in the field of steroid analysis. The pros and cons of the most important methods, such as immunoassays and mass spectrometry based methods will be discussed. The focus of the latter will lie on gas chromatography-mass spectrometry (GC-MS) as well as liquid chromatography-mass spectrometry (LC-MS). Selected analytical applications from our Deutsche Forschungsgemeinschaft Research Group FOR 1369 "Sulfated Steroids in Reproduction" will illustrate the contents. In brief, immunoassays have for long presented the traditional technique for steroid analysis. They are easy to set up. Only one analyte can be measured per immunoassay. Specificity problems can arise and caution has to be exerted especially regarding direct assays lacking purification steps. Mass spectrometry based methods provide structural information on the analyte and thus higher specificity. In combination with chromatographic techniques, they permit the simultaneous determination of a multitude of analytes. Highest specificity can be obtained using GC-MS, a sophisticated but most powerful tool for characterizing steroid metabolomes. LC-MS is a true high throughput technique and highly suited for detecting complex steroids. GC-MS and LC-MS are not competing but complementary techniques. Since reliable steroid determination requires extremely high expertise in the field of analytics as well as steroid biochemistry, it is recommended that collaborations and networking with highly specialized centers of expertise are developed.

Free oxysterols and bile acids including conjugates - Simultaneous quantification in human plasma and cerebrospinal fluid by liquid chromatography-tandem mass spectrometry

A liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI(+)-MS/MS) assay was developed and qualified for analyzing 35 analytes of the cholesterol metabolism, including free cholesterol, 17 free, non-esterified oxysterols and 17 free and conjugated bile acids in plasma and cerebrospinal fluid. As internal standards, 25 commercially available stable deuterium-labeled analogs of the analytes were used. Pre-analytical investigations included stability tests of analyte concentrations affected by different anticoagulation additives: lithium heparin-, citrate-, EDTA-K₃-stabilized plasma and serum, and the stability in EDTA whole blood at RT. This LC-ESI(+)-MS/MS method was successfully applied for the analysis of paired serum/cerebrospinal fluid samples of patients with and without blood-brain barrier disturbance, as well as of 100 plasma samples of a LIFE-Adult study sub-cohort. A fast and simple sample preparation including protein precipitation and on-line solid-phase extraction was developed. As little as 55 μL of human plasma/serum or cerebrospinal fluid were needed for the analysis. It was possible to separate isomeric oxysterols and bile acids within 23 min using a C18 core-shell column. The assay is capable of quantifying in a linear range of 0.8-250 ng mL^-1 for free hydroxycholesterols, 0.2-10 ng mL^-1 for dihydroxycholesterols, 0.2-500 ng mL^-1 for bile acids and 16-2000 μg mL^-1 for cholesterol with acceptable accuracy and precision. In cerebrospinal fluid one free oxysterols, five free and five conjugated bile acids could be quantified. No significant differences between patients with and without blood-brain barrier disturbance were obtained. In the LIFE-Adult sub-cohort two free oxysterols, four free and seven conjugated bile acids could be quantified in EDTA plasma. Men showed significantly higher concentrations of 26-OHC than women (p = 0.035). Furthermore, in women lower levels of cholic acid, glycocholic acid, glycodeoxycholic acid, chenodeoxycholic acid, glycochenodeoxycholic acid, glycoursodeoxycholic acid, glycolithocholic acid and higher levels of taurocholic acid, taurochenodeoxycholic acid, ursodeoxycholic acid/hyodeoxycholic acid were quantified.

Current state and recommendations for harmonization of serum/plasma 17-hydroxyprogesterone mass spectrometry methods

Background:

Mass spectrometry (MS)-based 17-hydroxyprogesterone (17OHP) methods show considerable variation in results in external quality assurance (EQA) programs. An understanding of the current status of MS-based serum/plasma 17OHP quantification is important to facilitate harmonization.

Methods:

A 50-item e-survey related to (1) laboratory characteristics, (2) pre-analytical considerations and (3) analysis of 17OHP was developed and circulated to clinical MS laboratories via professional associations in Asia Pacific, Europe and North America.

Results:

Forty-four laboratories from 17 countries completed the survey. Sample preparation varied between laboratories with protein precipitation and liquid-liquid extraction being the most common processes. Analyte separation was most commonly achieved by liquid chromatography (LC) using a C18 column and mobile phases of water, methanol and formic acid. The ions selected for quantification were 331>97 m/z or 331>109 m/z. Alternative transition ions were used as qualifiers. Twenty-seven of 44 respondents reported preparing their calibrators in-house and variations in material purity and matrix were evident. Nine of 44 laboratories did not participate in an EQA program, and half did not know if their method separated out isobars. The reference intervals, and also their partitioning, reported by the laboratories were highly discrepant, in some cases, by multiple folds.

Conclusions:

Although MS-based methods are similar in many facets, they are highly disparate. Five recommendations have been developed as an outcome of this survey to support the continued improvement of analysis of serum/plasma 17OHP by MS.

Evaluation of hair cortisol and cortisone change during pregnancy and the association with self-reported depression, somatization, and stress symptoms

Hair cortisol levels are used to measure long-term stress, while its inactive metabolite cortisone is often not assessed. We measured hair cortisol concentrations (HCC) and hair cortisone concentrations (HCNC) via liquid chromatography quadrupole linear ion trap mass spectrometry (LC-MS³) in 62 pregnant women who participated in the LIFE CHILD STUDY in their 2nd and 3rd trimester between 12/2011 and 11/2014. Sociodemographic factors, pregnancy-related factors, and hair characteristics were assessed. Degree of severity of depression, somatization, and stress were evaluated in both trimesters with a self-reported Patient Health Questionnaire (PHQ). Multivariate regression analyses were conducted between HCC and potential influencing factors, as well as with subscales of the PHQ, with HCNC and with the ratio of HCNC to HCC. Spearman correlation coefficients were calculated between steroid concentrations and subscale scores of the PHQ, as well as between the log₂-fold change in HCC and HCNC and the change in PHQ subscale scores. HCC increased 1.3-fold and HCNC increased 1.5-fold by the 3rd trimester. HCNC was more than three times higher than HCC in both trimesters. We found significant associations of PHQ subscores with HCNC. The PHQ depression score was negatively correlated with HCNC in the 2nd trimester (p < .05). The PHQ stress score change was negatively correlated with the fold change of HCNC (p < .05) and with the change in the ratio of HCNC to HCC (p < .001). Our study suggests an association of cortisol/cortisone metabolism with self-reported stress in the 2nd and 3rd trimester of pregnancy. Since associations with PHQ subscores were only found with cortisone or the ratio of cortisone to cortisol, but not with cortisol alone, both cortisone and cortisol should be used as a marker for stress in pregnant woman.

Testosterone-like immunoreactivity in hair measured in minute sample amounts - a competitive radioimmunoassay with an adequate limit of detection

The concentrations of testosterone deposited in hair during hair growth may provide a retrospective reflection of the concentrations of bioactive testosterone in plasma. The objective of this study was to develop a radioimmunoassay with a sufficiently low limit of detection to measure the testosterone-like immunoreactivity in smaller hair samples (5 mg) than used in earlier studies, and to compare three different extraction procedures. The competitive radioimmunoassay consisted of a polyclonal antiserum (immunogen testosterone-7α-BSA) and a radioligand synthesised from testosterone-3-CMO-histamine. The within-assay and total coefficients of variation in the working range was 3% and 4.5%, respectively. The limit of detection was 0.87 pg/mL, which is equivalent to 0.12 pg/mg testosterone in 5 mg of hair. The concentration of testosterone-like immunoreactivity in hair samples was 1.23 (SD 0.47) pg/mg in women and 2.67 (SD 0.58) pg/mg in men (pulverised hair). Significantly improved precision was found when pulverised hair was used compared to non-pulverised hair. Our data indicate that pulverisation of the hair prior to hormone extraction is crucial. Detection limits fit for the intended purpose are achievable with 5 mg samples of hair.

Simultaneous determination of thirteen different steroid hormones using micro UHPLC-MS/MS with on-line SPE system

Ultratrace analysis of sample components requires excellent analytical performance in terms of limits of quantitation (LOQ). Micro UHPLC coupled to sensitive tandem mass spectrometry provides state of the art solution for such analytical problems. Using on-line SPE with column switching on a micro UHPLC-MS/MS system allowed to decrease LOQ without any complex sample preparation protocol. The presented method is capable of reaching satisfactory low LOQ values for analysis of thirteen different steroid molecules from human plasma without the most commonly used off-line SPE or compound derivatization. Steroids were determined by using two simple sample preparation methods, based on lower and higher plasma steroid concentrations. In the first method, higher analyte concentrations were directly determined after protein precipitation with methanol. The organic phase obtained from the precipitation was diluted with water and directly injected into the LC-MS system. In the second method, low steroid levels were determined by concentrating the organic phase after steroid extraction. In this case, analytes were extracted with ethyl acetate and reconstituted in 90/10 water/acetonitrile following evaporation to dryness. This step provided much lower LOQs, outperforming previously published values. The method has been validated and subsequently applied to clinical laboratory measurement.

Twenty-four hour urinary cortisol excretion and the metabolic syndrome in prednisolone-treated renal transplant recipients

Chronic prednisolone treatment in renal transplant recipients (RTR) causes metabolic abnormalities, which cluster in the metabolic syndrome (MS). It also suppresses the hypothalamic-pituitaryadrenal (HPA)-axis. We investigated whether HPA-axis suppression, as measured by 24h urinary cortisol excretion, is associated with presence of the MS and its individual components, in outpatient RTR with a functioning graft for >1year. Urinary cortisol was measured in 24h urine, using LC-MS/MS (LOQ 0.30nmol/L). We included 563 RTR (age 51±12years; 54% male) at median 6.0 [IQR, 2.6-11.5] years post-transplantation. MS was present in 439/563 RTR (78%). Median 24h urinary cortisol excretion was 2.0 [IQR, 0.9-5.1]nmol/24h. Twenty-four hour urinary cortisol excretion was independently associated with MS presence (OR=0.80 [95% CI, 0.66-0.98], P=0.02). It was also independently associated with bodyweight (st.β=-0.11, P=0.007), waist circumference (st.β=-0.10, P=0.01), BMI (st.β=-0.14, P=0.001), fasting triglycerides (st.β=-0.15, P=0.001), diabetes (st.β=-0.12, P=0.005), and number of antihypertensives used (st.β=-0.13, P=0.003). Suppressed HPA-axis activity, as reflected by decreased 24h urinary cortisol excretion, is associated with higher prevalence of MS and its individual components (i.e. central obesity, dyslipidemia, diabetes, hypertension) in prednisolone-treated RTR. Assessment of 24h urinary cortisol excretion by LC-MS/MS may be a tool to monitor metabolic side-effects of prednisolone in RTR.

Online extraction of antihypertensive drugs and their metabolites from untreated human serum samples using restricted access carbon nanotubes in a column switching liquid chromatography system

A novel analytical method was developed to determine 5 antihypertensive drugs of different pharmacological classes (angiotensin-converting enzyme inhibitors, calcium channel blockers, α-2 adrenergic receptor agonists, angiotensin II receptor blockers, and aldosterone receptor antagonists) and some of their metabolites in human serum. The untreated samples were directly analyzed in a column switching system using an extraction column packed with restricted access carbon nanotubes (RACNTs) in an ultra-high performance liquid chromatography coupled to a mass spectrometer (UHPLC-MS/MS). The RACNTs column was able to exclude approximately 100% of proteins from the samples in 2.0min, maintaining the same performance for about 300 analytical cycles. The method was validated in accordance with Food and Drug Administration (FDA) guidelines, being linear for all the determined analytes in their respective analytical ranges (coefficients of determination higher than 0.99) with limits of detection (LODs) and quantification (LOQs) ranging from 0.09 to 10.85μgL^-1 and from 0.30 to 36.17μgL^-1, respectively. High recovery values (88-112%) were obtained as well as suitable results for inter and intra-assay accuracy and precision. The method provided an analytical frequency of 5 samples per hour, including the sample preparation and separation/detection steps. The validated method was successfully used to analyze human serum samples of patients undergoing treatment with antihypertensive drugs, being useful for pharmacometabolomic, pharmacogenomic, and pharmacokinetic studies.

Ultra-performance liquid chromatography-tandem mass spectrometry assay for determination of plasma nomegestrol acetate and estradiol in healthy postmenopausal women

A highly sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry method is described for the simultaneous determination of nomegestrol acetate (NOMAC), a highly selective progestogen, and estradiol (E2), a natural estrogen in human plasma. NOMAC was obtained from plasma by solid-phase extraction, while E2 was first separated by liquid-liquid extraction with methyl tert-butyl ether followed by derivatization with dansyl chloride. Deuterated internal standards, NOMAC-d5 and E2-d4 were used for better control of extraction conditions and ionization efficiency. The assay recovery of the analytes was within 90-99%. The analytes were separated on UPLC BEH C₁₈ (50 × 2.1 mm, 1.7 μm) column using a mobile phase comprising of acetonitrile and 3.0 mm ammonium trifluoroacetate in water (80:20, v/v) with a resolution factor (R_s ) of 3.21. The calibration curves were linear from 0.01 to 10.0 ng/mL for NOMAC and from 1.00 to 1000 pg/mL for E2, respectively. The intra- and inter-batch precision was ≤5.8% and the accuracy of quality control samples ranged from 96.7 to 103.4% for both analytes. The practical applicability of the method is demonstrated by analyzing samples from 18 healthy postmenopausal women after oral administration of 2.5 mg nomegestrol acetate and 1.5 mg estradiol film-coated tablets under fasting.

Multicenter performance evaluation of a second generation cortisol assay

Background:

Untreated disorders of the adrenocortical system, such as Cushing’s or Addison’s disease, can be fatal, and accurate quantification of a patient’s cortisol levels is vital for diagnosis. The objective of this study was to assess the analytical performance of a new fully-automated Elecsys® Cortisol II assay (second generation) to measure cortisol levels in serum and saliva.

Methods:

Four European investigational sites assessed the intermediate precision and reproducibility of the Cortisol II assay (Roche Diagnostics) under routine conditions. Method comparisons of the Cortisol II assay vs. liquid chromatography-tandem mass spectrometry (LC-MS/MS), the gold standard for cortisol measurement, were performed. Cortisol reference ranges from three US sites were determined using samples from self-reported healthy individuals.

Results:

The coefficients of variation (CVs) for repeatability, intermediate precision, and reproducibility for serum samples were ≤2.6%, ≤5.8%, and ≤9.5%, respectively, and for saliva were ≤4.4% and ≤10.9%, and ≤11.4%, respectively. Agreement between the Cortisol II assay and LC-MS/MS in serum samples was close, with a slope of 1.02 and an intercept of 4.473 nmol/L. Reference range samples were collected from healthy individuals (n=300) and serum morning cortisol concentrations (5–95th percentile) were 166.1–507 nmol/L and afternoon concentrations were 73.8–291 nmol/L. Morning, afternoon, and midnight saliva concentrations (95th percentile) were 20.3, 6.94, and 7.56 nmol/L, respectively.

Conclusions:

The Cortisol II assay had good precision over the entire measuring range and had excellent agreement with LC-MS/MS. This test was found suitable for routine diagnostic application and will be valuable for the diagnosis of adrenocortical diseases.