Liquid chromatography-tandem mass spectrometry assay for androstenedione, dehydroepiandrosterone, and testosterone with pediatric and adult reference intervals

Advances and challenges in liquid chromatography-spectrometry (LC-MS) methodology for quantifying androgens and estrogens in human serum and plasma

Accurate quantification of androgens and estrogens is critical for elucidating their roles in endocrine disorders and advancing research on their functions in human biology and pathophysiology. This review highlights recent advances and ongoing challenges in liquid chromatography- mass spectrometry (LC- MS) methodology for quantifying androgens and estrogens in human serum and plasma. We summarized current approaches for analyzing the different forms of androgens and estrogens, along with their reported levels in publications from 2010 to the present. These published levels pointed out the inconsistencies in reference intervals across studies. To address these issues, advances in derivatization methods and chromatographic separation techniques are reviewed. Future perspectives for improving the accuracy and consistency of hormone quantification in clinical and research settings were also proposed.

Toward a Robust Definition of Sport Sex

Elite individual sports in which success depends on power, speed, or endurance are conventionally divided into male and female events using traditional binary definitions of sex. Male puberty creates durable physical advantages due to the 20- to 30-fold increase in circulating testosterone producing a sustained uplift in men's muscle, bone, hemoglobin, and cardiorespiratory function resulting from male puberty and sustained during men's lives. These male physical advantages provide strong justification for a separate protected category of female events allowing women to achieve the fame and fortune from success they would be denied if competing against men. Recent wider social acceptance of transgender individuals, together with the less recognized involvement of intersex individuals, challenge and threaten to defeat the sex classifications for elite individual female events. This can create unfair advantages if seeking inclusion into elite female events of unmodified male-bodied athletes with female gender identity who have gained the physical advantages of male puberty. Based on reproductive physiology, this paper proposes a working definition of sport sex based primarily on an individual's experience of male puberty and can be applied to transgender and various XY intersex conditions. Consistent with the multidimensionality of biological sex (chromosomal, genetic, hormonal, anatomical sex), this definition may be viewed as a multistrand cable whose overall strength survives when any single strand weakens or fails, rather than as a unidimensional chain whose strength is only as good as its weakest link.

Steroid profiling in human primary teeth via liquid chromatography-tandem mass spectrometry for long-term retrospective steroid measurement

Steroid hormones are important modulators of many physiological processes, and measurements of steroids in blood, saliva, and urine matrices are widely used to assess endocrine pathologies and stress. However, these matrices cannot be used to retrospectively assess early-life stress and developmental endocrine pathologies, because they do not integrate steroid levels over the long term. A novel biological matrix in which to measure steroids is primary teeth (or "baby teeth"). Primary teeth develop early in life and accumulate various endogenous molecules during their gradual formation. Here, we developed and validated the first assay to measure steroids in human primary teeth using liquid chromatography-tandem spectrometry (LC-MS/MS). Our assay is highly sensitive, specific, accurate, and precise. It allows for the simultaneous quantification of 17 steroids in primary teeth (16 of which have not been examined previously in primary teeth). Overall, steroid levels in primary teeth were relatively low, and 8 steroids were quantifiable. Levels of dehydroepiandrosterone, cortisol, and progesterone were the highest of the 17 steroids examined. Next, we used this assay to perform steroid profiling in primary teeth from males and females. The same 8 steroids were quantifiable, and no sex differences were found. Levels of androgens (androstenedione and testosterone) were positively correlated, and levels of glucocorticoids (cortisol, cortisone, corticosterone, 11-dehydrocorticosterone) were also positively correlated. These data demonstrate that multiple steroids can be quantified by LC-MS/MS in human primary teeth, and this method potentially provides a powerful new way to retrospectively assess early-life stress and developmental endocrine pathologies.

Effectiveness of blood steroidal passport markers for detecting testosterone abuse in Asians

The World Anti-Doping Agency (WADA) has introduced an Athlete Biological Passport (ABP) with a steroidal module, which is intended for the monitoring of longitudinal profiles of an athlete's steroid variables in urine to identify endogenous anabolic androgenic steroids that are administered exogenously. It has been in use since 2014. The prevalence of UGT2B17 gene deletion with relatively low levels of testosterone (T) glucuronide in urine is high in the Asian region. There are cases in which urinary T is below the detection limit in specific urine samples, for example, diluted urine, urine collected from females, or urine collected from UGT2B17 deletion individuals. Additional steroid markers T, 4-androstenedione (A4), and the T/A4 ratio in serum were newly added to the ABP steroidal module by WADA in 2023 to compensate for the urine steroid profile. In this study, populations of blood steroid markers in Asians (n = 510) were investigated and classified according to UGT2B17 polymorphism to confirm the effectiveness of blood steroid markers in monitoring Asian athletes. No significant difference in the T/A4 ratio was observed between the genotypes. Furthermore, an administration study of T enanthate in females (n = 10) who were classified according to UGT2B17 genotypes was performed. The concentration of T and the T/A4 ratio were found to be significantly increased in all post-administration samples until 15 days after administration (p < 0.01). The overall results supported the high effectiveness of subject-based monitoring for serum T and T/A4 ratio for recently identified shortcomings in the detection of T abuse in Asians.

In situ fabrication of covalent organic frameworks on solid-phase microextraction probes coupled with electrospray ionization mass spectrometry for enrichment and determination of androgens in biosamples

Solid-phase microextraction (SPME) coupled with electrospray ionization mass spectrometry (ESI-MS) was developed for rapid and sensitive determination of endogenous androgens. The SPME probe is coated with covalent organic frameworks (COFs) synthesized by reacting 1,3,5-tri(4-aminophenyl)benzene (TPB) with 2,5-dioctyloxybenzaldehyde (C8PDA). This COFs-SPME probe offers several advantages, including enhanced extraction efficiency and stability. The analytical method exhibited wide linearity (0.1-100.0 µg L-1), low limits of detection (0.03-0.07 µg L-1), high enrichment factors (37-154), and satisfactory relative standard deviations (RSDs) for both within one probe (4.0-14.8%) and between different probes (3.4-12.7%). These remarkable performance characteristics highlight the reliability and precision of the COFs-SPME-ESI-MS method. The developed method was successfully applied to detect five kinds of endogenous androgens in female serum samples, indicating that the developed analytical method has great potential for application in preliminary clinical diagnosis.

Hair cortisol and dehydroepiandrosterone and their associations with optimism and pessimism in older people

The cumulative negative effects of prolonged Hypothalamic-Pituitary-Adrenal axis (HPA axis) activation are associated with several age-related diseases. Some psychological traits such as optimism and pessimism have been shown to be related to both health and the stress response, although their relationship with the HPA axis is inconclusive. More stable HPA axis biomarkers, such as hair samples of cortisol (HC) and dehydroepiandrosterone (HDHEA), would help to clarify the association between these psychological traits and HPA axis functioning. The main aim of this study was to test the relationships between optimism and pessimism and chronic stress biomarkers measured in hair (HC and HDHEA). Additionally, a secondary objective was to explore sex differences in HC and HDHEA levels and their relationship with these psychological traits. We measured optimism, pessimism, and their combination (dispositional optimism) using the Life Orientation Test Revised (LOT-R) and chronic stress biomarkers (HC and HDHEA) in 119 healthy participants (46 men and 73 women) between 56 and 81 years old who belonged to a university program. Regression analyses controlling for perceived stress and BMI indicated that higher dispositional optimism was related to lower HC and HC:HDHEAratio (β = -0.256, p = .008 and β = -0.300, p = .002, respectively). More specifically, higher pessimism was related to higher HC (β = 0.235; p = .012) and HC:HDHEAratio (β = 0.240; p = .011), whereas higher optimism was associated with a lower HC:HDHEAratio(β = -0.205; p = .031). Moderation analyses showed no sex differences. To date, this is the first study to investigate the link between these traits and HC and HDHEA in older people. Our results confirm that positive and negative expectations about the future (i.e. optimism and pessimism) may play an important role in health due to their relationship with the HPA axis. They also strengthen the idea that the negative effects of pessimism have a greater weight than the protective effects of optimism in their relationship with HPA axis regulation.

Methodological considerations in determining sex steroids in children: comparison of conventional immunoassays with liquid chromatography-tandem mass spectrometry

OBJECTIVES

In laboratory medicine, external quality assessment (EQA) schemes have become versatile tools for detecting analytical flaws. However, EQA schemes are lacking for pediatric sex steroid levels. We aimed to investigate the suitability of different estradiol and testosterone immunoassays in a pediatric setting in comparison with clinical liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays.

METHODS

The study was conducted by staff and the advisory group on endocrinology at Equalis, the Swedish provider of EQA schemes for laboratory medicine. The test material consisted of five pooled serum samples from children who were either prepubertal or in puberty. Clinical laboratories enrolled in Equalis EQA schemes for estradiol and testosterone were invited to participate, as were clinical laboratories using LC-MS/MS-assays. Samples were analyzed by either routine immunoassays (n=18) or in-house LC-MS/MS assays (n=3).

RESULTS

For estradiol, LC-MS/MS assays showed a high degree of conformity with interlaboratory coefficients of variation (CV) below 24.2 %. Reported levels were between 4.9 ± 1.2 and 33.9 ± 1.6 pmol/L (group mean ± standard deviation). The direct immunoassays had lower precision; their CVs were up to 81.4 %. Reported concentrations were between 25.3 ± 18.1 and 45.7 ± 19.4 pmol/L, an overestimation compared to LC-MS/MS. Testosterone LC-MS/MS also showed a high degree of conformity, CVs were below 13.4 %, and reported concentrations were from 0.06 ± 0.00 to 1.00 ± 0.11 nmol/L. The direct immunoassays had a larger discrepancy between results; CVs were up to 95.8 %. Concentrations were between 0.12 ± 0.11 and 0.85 ± 0.23 nmol/L.

CONCLUSIONS

For the safe diagnosis and determination of sex steroids in children, analysis with mass spectrometry-based methods is recommended.

The Biological Basis of Sex Differences in Athletic Performance: Consensus Statement for the American College of Sports Medicine

ABSTRACT

Biological sex is a primary determinant of athletic performance because of fundamental sex differences in anatomy and physiology dictated by sex chromosomes and sex hormones. Adult men are typically stronger, more powerful, and faster than women of similar age and training status. Thus, for athletic events and sports relying on endurance, muscle strength, speed, and power, males typically outperform females by 10%-30% depending on the requirements of the event. These sex differences in performance emerge with the onset of puberty and coincide with the increase in endogenous sex steroid hormones, in particular testosterone in males, which increases 30-fold by adulthood, but remains low in females. The primary goal of this consensus statement is to provide the latest scientific knowledge and mechanisms for the sex differences in athletic performance. This review highlights the differences in anatomy and physiology between males and females that are primary determinants of the sex differences in athletic performance and in response to exercise training, and the role of sex steroid hormones (particularly testosterone and estradiol). We also identify historical and nonphysiological factors that influence the sex differences in performance. Finally, we identify gaps in the knowledge of sex differences in athletic performance and the underlying mechanisms, providing substantial opportunities for high-impact studies. A major step toward closing the knowledge gap is to include more and equitable numbers of women to that of men in mechanistic studies that determine any of the sex differences in response to an acute bout of exercise, exercise training, and athletic performance.

Low serum dehydroepiandrosterone is associated with diabetic dyslipidemia risk in males with type 2 diabetes

Objective

Sex steroid hormones are associated with the advancement of metabolic diseases such as dyslipidemia. This cross-sectional study aimed to investigate the relationship between dehydroepiandrosterone, dehydroepiandrosterone sulfate, androstenedione, and testosterone levels and the risk of dyslipidemia in people with type 2 diabetes mellitus.

Materials and Methods

The analysis included 1,927 patients with type 2 diabetes mellitus. Serum dehydroepiandrosterone, dehydroepiandrosterone sulfate, androstenedione, and testosterone levels were determined using lipid chromatography-tandem mass spectrometry. Multivariable analyses were performed to investigate the association between the variables and dyslipidemia.

Results

The multivariable-adjusted odds ratio (OR) and 95% confidence interval (CI) of dyslipidemia across DHEA tertiles were 0.39 and 0.24-0.64, respectively (p trend = 0.001). This relationship was still maintained when analyzed as a continuous variable (odds ratio, 0.96; 95% confidence interval, 0.92-0.99; P < 0.01). However, in males with type 2 diabetes mellitus, no significant correlations were found between rising levels of dehydroepiandrosterone sulfate, androstenedione, and total testosterone and the risk of dyslipidemia (all P > 0.05). Furthermore, there was no significant association between androgen precursors and total testosterone with regard to the risk of developing dyslipidemia (all P > 0.05).

Conclusions

Serum dehydroepiandrosterone levels were substantially and adversely correlated with dyslipidemia in adult men with T2DM. These results indicated that dehydroepiandrosterone may have an essential role in the development of dyslipidemia. More prospective research is required to validate this link.

Adrenal gland responses surgical castration and immunocastration by different compensatory manners to increase DHEA secretion

Androgen from the testis and weak androgens from the adrenal cortex may interact with each other and affect their synthesis and secretion due to their similar functions. The purpose of this study was to investigate the compensatory effect of adrenal in rats after immunocastration and surgical castration, and the interaction between the hypothalamic-pituitary-testis (HPT) axis and the hypothalamic-pituitary-adrenal (HPA) axis. 24 male SD rats aged 8 weeks were randomly divided into three groups and accepted treatments: surgical castration group, immunocastration group and control group. In both surgical castration and immunocastration groups, the secretion of adrenocorticotropic hormone (ACTH) and dehydroepiandrosterone (DHEA) hormones was significantly increased compared with the control group (p < 0.05). In the HPT axis of the immunocastration group, the KISS1 expression was up-regulated, whereas GPR54, LH and LHR expression were down-regulated (p < 0.05). The expression levels of CRH, POMC and MC2R genes were also significantly up-regulated (p < 0.05). In addition, in the immunocastration group, the expression of adrenal LHR mRNA expression was decreased (p < 0.05). The expression of HPT axis genes and adrenal LHR were up-regulated in the surgical castration group (p < 0.05). These results show that in both immunocastration and surgical castration, adrenal androgen is increased, suggesting that the adrenal gland plays a compensatory role. Moreover, it also shows that different castration treatments have effects on adrenal steroid secretion through different mechanisms.

Effect of complete suppression of androstenedione on auxological development in prepubertal patients with classical congenital adrenal hyperplasia

OBJECTIVES

Children with classical congenital adrenal hyperplasia (CAH) require glucocorticoid (GC) substitution due to impaired cortisol synthesis. To avoid over- or undertreatment, one has to consider auxology as well as biochemical parameters for adrenal derived steroids like androstenedione (A4) and 17-hydroxyprogesterone (17-OHP). There are no established reference values for A4 and 17-OHP in CAH.

METHODS

We performed a retrospective study in 53 prepubertal patients with CAH. Datasets of patients were included if the plasma A4 values of the respective clinical visit were under the limit of quantification. Related 17-OHP values were extracted as well as height/length, weight, dose of hydrocortisone, HC regimen, bone age and stages of pubertal development.

RESULTS

Median hydrocortisone doses were in most observations within the recommended reference ranges. Hydrocortisone has a significant negative influence on 17-OHP values and HSDS. Age has a positive significant influence on 17-OHP, BMI-SDS, and HSDS. Median height standard-deviation-score (HSDS) was beneath 0 at all times, but showed an increasing trend in both sexes. Median body mass index standard-deviation-score (BMI-SDS) was above 0 at all times and showed an increasing trend as well.

CONCLUSIONS

With guideline-compliant doses of hydrocortisone, suppression of A4 at the respective time of day is possible in prepubertal children. Although HC has a significant negative influence on HSDS, increasing values for HSDS and HC are observed with increasing age. Thus, A4 suppression at the respective time point does not hinder regular growth. An increase in body mass index can already be observed as early as in prepuberty.

Mass Spectrometry Based on Chemical Derivatization Has Brought Novel Discoveries to Lipidomics: A Comprehensive Review

Lipids, as one of the most important organic compounds in organisms, are important components of cells and participate in energy storage and signal transduction of living organisms. As a rapidly rising field, lipidomics research involves the identification and quantification of multiple classes of lipid molecules, as well as the structure, function, dynamics, and interactions of lipids in living organisms. Due to its inherent high selectivity and high sensitivity, mass spectrometry (MS) is the "gold standard" analysis technique for small molecules in biological samples. The combination chemical derivatization with MS detection is a unique strategy that could improve MS ionization efficiency, facilitate structure identification and quantitative analysis. Herein, this review discusses derivatization-based MS strategies for lipidomic analysis over the past decade and focuses on all the reported lipid categories, including fatty acids and modified fatty acids, glycerolipids, glycerophospholipids, sterols and saccharolipids. The functional groups of lipids mainly involved in chemical derivatization include the C=C group, carboxyl group, hydroxyl group, amino group, carbonyl group. Furthermore, representative applications of these derivatization-based lipid profiling methods were summarized. Finally, challenges and countermeasures of lipid derivatization are mentioned and highlighted to guide future studies of derivatization-based MS strategy in lipidomics.

Pediatric reference intervals for endocrine markers in healthy children and adolescents on the Liaison XL (DiaSorin) immunoassay system

OBJECTIVES

Prominent physiological changes occurring throughout childhood and adolescence necessitate the consideration of age and sex in biomarker interpretation. Critical gaps exist in pediatric reference intervals (RIs) for specialized endocrine markers, despite expected influence of growth and development. The current study aimed to establish and/or verify RIs for six specialized endocrine markers on a specialized immunoassay system.

METHODS

Samples were collected from healthy children and adolescents (5 to <19 years) and apparently healthy outpatients (0 to <5 years) as part of the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER). Serum samples were analysed for aldosterone, renin (plasma), thyroglobulin, anti-thyroglobulin, growth hormone, and insulin-like growth factor-1 (IGF-1) on the Liaison XL (DiaSorin) immunoassay platform. RIs (2.5th and 97.5th percentiles) were established for aldosterone, renin, thyroglobulin, anti-thyroglobulin, and growth hormone. Manufacturer-recommended pediatric RIs for IGF-1 were verified.

RESULTS

Age-specific RIs were established for aldosterone, renin, and thyroglobulin, while no age-specific differences were observed for anti-thyroglobulin or growth hormone. IGF-1 was the only endocrine marker studied that demonstrated significant sex-specific differences. Manufacturer-recommended IGF-1 RIs were verified for children aged 6 to <19 years, while those for children aged 0 to <6 years did not verify.

CONCLUSIONS

This study marks the first time that pediatric RIs for aldosterone and renin were established in the CALIPER cohort and highlights the dynamic changes that occur in water and sodium homeostasis during the first years of life. Overall, these data will assist pediatric clinical laboratories in test result interpretation and improve clinical decision-making for patients tested using Liaison immunoassays.

Impact of growth, gonadal hormones, adiposity and the sodium-to-potassium ratio on longitudinal adolescent measures of blood pressure at puberty

Blood pressure (BP) rises rapidly at puberty. While this is partly due to normal development, factors like excess adiposity and a high intake of dietary sodium relative to potassium may contribute to a true increase in hypertension risk. This study aimed to assess the relative impact of growth, gonadal hormones, adiposity and the sodium-to-potassium ratio (Na:K) on longitudinal BP measures at puberty. This study analysed data from a three-year longitudinal cohort study of pubertal adolescents. Anthropometry, body composition (bio-electrical impedance), serum testosterone and oestradiol (mass spectrometry) were measured annually. Na:K was measured from three-monthly urine samples. These variables were used to predict annual BP measures using mixed modelling and ordinal regression. Data from 325 adolescents (11.7 ± 1.0 y; 55% male) were analysed, showing typical growth patterns at puberty. Systolic BP increased over time in both sexes (p < 0.01), with boys exhibiting a significantly steeper rise compared to girls. Adiposity variables (BMI z-score, percent body fat, fat mass, waist-to-height ratio) strongly and consistently predicted systolic and diastolic BP in both sexes (all p < 0.05). Systolic BP was also significantly and positively related to height (p < 0.05). No associations with BP were identified in either sex for gonadal hormones or Na:K. Similar results were obtained when BP was classified into hypertension categories. Relative to other developmental and diet-related variables tested, adiposity was found to be the strongest most consistent predictor of BP in pubertal adolescents. Findings highlight the importance of dedicated youth obesity management interventions and policy measures for reducing long-term hypertension and cardiovascular disease risks.Australian New Zealand Clinical Trials Registry ACTRN12617000964314.

Biomarkers in congenital adrenal hyperplasia

Monitoring of hormone replacement therapy represents a major challenge in the management of congenital adrenal hyperplasia (CAH). In the absence of clear guidance and standardised monitoring strategies, there is no consensus among clinicians regarding the relevance of various biochemical markers used in practice, leading to wide variability in their application and interpretation. In this review, we summarise the published evidence on biochemical monitoring of CAH. We discuss temporal variations of the most commonly measured biomarkers throughout the day, the interrelationship between different biomarkers, as well as their relationship with different glucocorticoid and mineralocorticoid treatment regimens and clinical outcomes. Our review highlights significant heterogeneity across studies in both aims and methodology. However, we identified key messages for the management of patients with CAH. The approach to hormone replacement therapy should be individualised, based on the individual hormonal profile throughout the day in relation to medication. There are limitations to using 17-hydroxyprogesterone, androstenedione and testosterone, and the role of additional biomarkers such 11-oxygenated androgens which are more disease specific should be further established. Noninvasive monitoring via salivary and urinary steroid measurements is becoming increasingly available and should be considered, especially in the management of children with CAH. Additionally, this review indicates the need for large scale longitudinal studies analysing the interrelation between different monitoring strategies used in clinical practice and health outcomes in children and adults with CAH.

Androgens in women: Establishing reference intervals for dehydroepiandrostenedione sulphate and androstenedione on the Roche Cobas

Introduction

Immunoassays are the most common method in routine practice for measuring androgens in women. Study's aim was to establish new population specific indirect reference intervals (RI) for dehydroepiandrostenedione sulphate (DHEAS) and for new androstenedione test available on automated Roche Cobas electrochemiluminescent immunoassay method.

Materials and methods

From extracted laboratory records, testosterone, sex hormone binding globulin and follicle-stimulating hormone were used as reference tests to exclude possibly diseased women. After the data selection steps, the study included 3500 subjects for DHEAS and 520 for androstenedione aged 20-45 years. To evaluate the need for age partitioning, we calculated standard deviation ratio and bias ratio. For each hormone, 90% and 95% RIs were calculated with appropriate statistical method.

Results

Total age group (20-45 years) 95% RIs were: 2.77-11.50 µmol/L for DHEAS and 2.48-8.89 nmol/L for androstenedione. Age-stratified 95% RIs for DHEAS were: 3.65-12.76 µmol/L (20-25 years); 2.97-11.50 µmol/L (25-35 years) and 2.30-9.83 µmol/L (35-45 years). Age-stratified 95% RIs for androstenedione were: 3.02-9.43 nmol/L (20-30 years) and 2.23-7.75 nmol/L (30-45 years).

Conclusion

New RIs for DHEAS were slightly wider for age group 20-25 and 35-45, while the differences in the age group 25-35 years were more pronounced. Androstenedione RI showed significantly higher concentrations than the manufacturer's. Age-related decrease of androgens should be considered when calculating RIs. We propose population specific, age-stratified RIs for DHEAS and androstenedione on electrochemiluminescent method, which should improve test interpretation in women of reproductive age.

VALIDATION OF ENZYME-LINKED IMMUNOSORBENT ASSAY TECHNIQUES TO MEASURE SERUM DEHYDROEPIANDROSTERONE (DHEA) AND DHEA-S IN NARWHALS (MONODON MONOCEROS)

Narwhals (Monodon monoceros) are increasingly exposed to anthropogenic disturbances that may increase their stress levels with unknown consequences for the overall population dynamics. The validation and measurement of chronic stress biomarkers could contribute toward improved understanding and conservation efforts for this species. Dehydroepiandrosterone (DHEA) and its sulfated metabolite DHEA-S are collectively referred to as DHEA(S). Serum DHEA(S) concentrations combined in ratios with cortisol [cortisol/DHEA(S)] have been shown to be promising indicators of chronic stress in humans, domestic animals, and wildlife. During field tagging in 2017 and 2018 in Baffin Bay, Nunavut, Canada, 14 wild narwhals were sampled at the beginning and end of the capture-tagging procedures. Serum DHEA(S) were measured with commercially available competitive enzyme-linked immunosorbent assays (ELISA) developed for humans. A partial validation of the ELISA assays was performed by the determination of the intra-assay coefficient of variation, confirmation of the DHEA(S) dilutional linearity, and the calculation of the percentage of recovery. Mean values (nanograms per milliliter ± standard error of the mean) of narwhal serum cortisol, DHEA(S), and cortisol/DHEA(S) ratios, at the beginning and at the end of handling, respectively, are reported (cortisol = 30.74 ± 4.87 and 41.83 ± 4.83; DHEA = 1.01 ± 0.52 and 0.99 ± 0.50; DHEA-S = 8.72 ± 1.68 and 7.70 ± 1.02; cortisol/DHEA = 75.43 ± 24.35 and 84.41 ± 11.76, and cortisol/DHEA-S = 4.16 ± 1.07 and 6.14 ± 1.00). Serum cortisol and cortisol/DHEA-S were statistically higher at the end of the capture (P= 0.024 and P= 0.035, respectively). Moreover, serum cortisol at the end of handling was positively correlated to total body length (P = 0.042) and tended to be higher in males (P = 0.086). These assays proved easy to perform, rapid, and suitable for measuring serum DHEA(S) of narwhals and that calculated cortisol/DHEA(S) are potential biomarkers for chronic stress in narwhals and possibly other cetaceans.

A novel fully-automated method to measure steroids in serum by liquid chromatography-tandem mass spectrometry

Background

Steroids play a key role in numerous physiological processes. Steroid determination is a useful tool to explore various endocrine diseases. Because of its specificity, mass spectrometry is considered to be a reference method for the determination of steroids in serum compared to radioimmunoassay. This technology could progress towards more automation for the optimal organization of clinical laboratories and ultimately for the benefit of patients.

Methods

A fully automated ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed and fully validated to determine five steroids in serum. Sample preparation was based on protein precipitation with filtration followed by online solid phase extraction. Chromatographic separation was performed using a biphenyl stationary phase.

Results

The method was successfully validated according to European Medicine Agency guidelines. Coefficients of variation did not exceed, respectively, 8.4% and 8.1% for intra- and inter-assay precision. Method comparison with radioimmunoassay showed a proportional bias for all compounds, except for testosterone in men. Comparison with another LC-MS/MS method demonstrated acceptable concordance for all steroids, although a small bias was observed for androstenedione.

Conclusion

The novelty of this method is that it has been fully automated. Automation provides benefits in traceability and allows significant savings in cost and time.

Establishing and Verifying a Robust Liquid Chromatography–Tandem Mass Spectrometry Method to Simultaneously Measure Seven Androgens Present in Plasma Samples

Objectives: To develop a robust liquid chromatography–tandem mass spectrometry (LC–MS/MS) method to simultaneously measure seven human plasma androgens, namely testosterone (T), dihydrotestosterone (DHT), androstenedione (A4), dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), 11-ketotestosterone (11-KetoT), and 11β-hydroxytestosterone (11β-OHT). Design and Methods: Plasma was extracted via a solid phase extraction method, and the analytical performance of the assay was validated according to the Clinical & Laboratory Standards Institute guidelines. Overall, 73 apparently healthy volunteers were recruited to evaluate the distribution of these seven androgens; their levels in 25 females with acne and 33 obese females were also evaluated. Results: The developed method exhibited a good precision, with the total coefficient variations (CV) and the intra-assay CVs being within 10%. Furthermore, the recoveries of T, DHT, A4, DHEA, DHEAS, 11-KetoT, and 11β-OHT were 90.3–105.8, 88.7–98.1, 92.4–102.5, 90.5–106.7, 87.6–99.9, 93.3–105.3, and 90.2–104.4%, respectively, and no significant matrix effect was observed after internal standard correction (<20%). Moreover, the limits of quantification were 0.01, 0.01, 0.01, 0.10, 5.00, 0.02, and 0.02 ng/mL for T, DHT, A4, DHEA, DHEAS, 11-KetoT, and 11β-OHT, respectively, which are adequate for their accurate measurement in human plasma samples. It was also determined that patients diagnosed with acne had significantly higher levels of DHT, A4, and DHEAS, while those suffering from obesity had significantly higher levels of T and A4 but lower levels of DHT. Conclusions: A robust LC-MS/MS method for the simultaneous determination of seven androgens in plasma samples was successfully established and validated, which plays important roles in clinical application.

Pediatric reference intervals for Free Testosterone, 17-OH Progesterone, Androstenedione, and IGF-1 with chemiluminescence immunoassay

BACKGROUND

The aim of the study was to produce age and sex specific pediatric reference intervals (RIs) on a fully automated chemiluminescent immunoassay (CLIA) system.

MATERIAL AND METHOD

A total of 1586 patients' remnant sera were included in the study and free testosterone (FT), 17-OH progesterone (17OHP), androstenodione (A4) and insulin-like growth factor-1 (IGF-1) parameters were measured on MAGLUMI 2000 (Shenzhen New Industries Biomedical Engineering Co., Ltd. (Snibe), Shenzhen, China) CLIA analyser. After appropriate age and gender partitioning, specific intervals were calculated according to Clinical Laboratory Standart Institute's (CLSI) C28-A3 protocol.

RESULTS

All analytes showed sex and age dependent concentrations requiring several subgroups with specific reference intervals. 17OHP and A4 were found high with birth, declined thereafter: 17OHP by the end of 12 months and A4 by 6 months. So this period was also partitioned for these two hormones. All showed gradual increases by the end of 18 years. 17OHP, A4 and IGF-1 of girls were higher than boys around puberty as the result of earlier sexual development and maturation. FT values of boys and girls didn't differ from each other upto 10 years of age but boys had significantly higher values than girls afterwards. IGF-1 values gradually increase in both sexes upto the ages of 13, girls with significantly higher values than boys. In 13-18 years no significant gender difference was found.

CONCLUSIONS

We present method specific pediatric RIs, which are comparable with medical literature, necessary for interpretation of patient results.

Quantitation of Estradiol and Testosterone in Serum Using LC-MS/MS

Adult and pediatric endocrinology and oncology often requires measuring serum estrogens and testosterone at very low concentrations. Conventional immunoassay methods often lack the required performance to meet this analytical need, and mass spectrometry techniques must be employed. Our aim was to develop a sensitive HPLC-MS/MS assay for both estradiol (E2) and testosterone (Te) in serum, utilizing commercially available calibrators and without the need for chemical derivatization. Serum samples, after the addition of an internal standard, are combined with a hexane:ethyl acetate extraction solution. The samples are vortexed, and the organic layer is decanted into a clean sample tube and evaporated to dryness under a stream of nitrogen. The samples are reconstituted in a water:methanol solution and separated chromatographically using a reversed-phase HPLC column. Subsequent mass spectrometry is performed using both positive ion mode for Te and negative ion mode for E2.

Endogenous sex hormones, aromatase activity and lung cancer risk in postmenopausal never-smoking women

Although reproductive factors have been repeatedly associated with lung cancer risk, no study to date has directly evaluated the relationship with endogenous sex hormones nor with aromatase activity in postmenopausal never-smoking women. A case-control study of 397 incident lung cancer cases and their individually matched controls, nested within the Shanghai Women's Health Study, was conducted among postmenopausal women who were lifetime never smokers. Prediagnostic concentrations of sex hormones was quantitated using LC-MS/MS assays in plasma. The product-substrate molar ratio of estrone to androstenedione was used as an index of aromatase activity (IAA). Multivariable conditional logistic regression models were used to calculate odds ratios (ORs) for lung cancer. Baseline concentrations of estradiol, free testosterone and IAA were inversely associated with subsequent risk of lung cancer in multivariable-adjusted models. When further adjusted for body mass index, the inverse association with estradiol was attenuated and no longer statistically significant, but the association with free testosterone and IAA remained. In analyses confined to participants having never used menopausal hormone therapy in 376 case-control pairs, the inverse association with free testosterone and IAA was slightly strengthened. OR for the highest vs the lowest quartile of free testosterone was 0.55 (95% CI = 0.34-0.90; Ptrend  = .03), and the corresponding OR for IAA was 0.57 (95% CI = 0.34-0.96; Ptrend  = .04). Our study, for the first time, suggests that higher levels of circulating free testosterone and estimated aromatase activity may be associated with lower lung cancer risk in postmenopausal never-smoking women.

Quantitative analysis of specific androgens in serum and urine samples from male, pre, and postmenopausal subjects using LC-MRM-MS

Androgens are endogenous hormones that play a crucial role in the paracrine and intracrine hormone system to perform and maintain vital physiological functions. Altered levels of androgens are implicated in many diseases such as sexual dysregulation, breast cancer, prostate cancer, and heart diseases etc. In this manuscript we describe a liquid chromatography-mass spectrometry (LC-MS) method using multiple reaction monitoring (MRM) for quantitatively measuring specific androgens such as dehydroepiandrosterone, testosterone, androsterone sulphate, androstenedione, and dihydrotestosterone in serum and urine samples. Serum acquired from nine different subjects (three pre-menopausal women, three postmenopausal women, and three healthy males) were used to evaluate the developed methods. In the sample preparation methods for serum either protein precipitation or liquid-liquid extraction (LLE) was used while the analysis of urinary androgens used LLE. The extracted androgens were quantitatively measured using LC-MRM-MS to which known amounts of stable isotope labeled standards were added. This manuscript also presents a LC-MRM-MS method mode for the analysis of oxime derivatized androgens potentially to enhance the sensitivity of the assay if required, from urine and venous-drawn serum samples.

Plasma Testosterone and Androstenedione Levels Follow the Same Sex-Specific Patterns in the Two Pan Species

Simple Summary

Generally male mammals are more aggressive than their female peers. In these males, aggressive behavior is linked to levels of androgens; higher levels of testosterone are predictive of higher aggression rates or more severe aggression. There are some species where the pattern of sex-specific aggression is reversed, and it was hypothesized that high levels of androgens may be responsible for social dominance and aggressiveness in these females. Studies so far found that females of species with sex-reversed aggression patterns (e.g., spotted hyenas and ring-tailed lemurs) had lower plasma testosterone levels than their male peers, but a precursor of testosterone, androstenedione, was comparable or even higher in females than in males. This supported the idea that selection for female aggressiveness may be facilitated through augmented androgen secretion. Here we show that in two sister species, bonobos and chimpanzees, that differ in terms of sex-specific aggression patterns, females have lower plasma testosterone levels and higher plasma androstenedione levels than their male peers. Thus, our data do not support a theory of a role of female androgen levels on the expression of sex-specific patterns of aggression.

Abstract

In most animals, males are considered more aggressive, in terms of frequency and intensity of aggressive behaviors, than their female peers. However, in several species this widespread male-biased aggression pattern is either extenuated, absent, or even sex-reversed. Studies investigating potential neuro-physiological mechanisms driving the selection for female aggression in these species have revealed an important, but not exclusive role of androgens in the expression of the observed sex-specific behavioral patterns. Two very closely related mammalian species that markedly differ in the expression and degree of sex-specific aggression are the two Pan species, where the chimpanzee societies are male-dominated while in bonobos sex-biased aggression patterns are alleviated. Using liquid chromatography–mass spectrometry (LC-MS) methods, we measured levels of plasma testosterone and androstenedione levels in male and female zoo-housed bonobos (N = 21; 12 females, 9 males) and chimpanzees (N = 41; 27 females, 14 males). Our results show comparable absolute and relative intersexual patterns of blood androgen levels in both species of Pan. Plasma testosterone levels were higher in males (bonobos: females: average 0.53 ± 0.30 ng/mL; males 6.70 ± 2.93 ng/mL; chimpanzees: females: average 0.40 ± 0.23 ng/mL; males 5.84 ± 3.63 ng/mL) and plasma androstenedione levels were higher in females of either species (bonobos: females: average 1.83 ± 0.87 ng/mL; males 1.13 ± 0.44 ng/mL; chimpanzees: females: average 1.84 ± 0.92 ng/mL; males 1.22 ± 0.55 ng/mL). The latter result speaks against a role of androstenedione in the mediation of heightened female aggression, as had been suggested based on studies in other mammal species where females are dominant and show high levels of female aggressiveness.

Sex Differences in Pulmonary Hypertension

Pulmonary hypertension (PH) includes multiple diseases that share as common characteristic an elevated pulmonary artery pressure and right ventricular involvement. Sex differences are observed in practically all causes of PH. The most studied type is pulmonary arterial hypertension (PAH) which presents a gender bias regarding its prevalence, prognosis, and response to treatment. Although this disease is more frequent in women, once affected they present a better prognosis compared to men. Even if estrogens seem to be the key to understand these differences, animal models have shown contradictory results leading to the birth of the estrogen paradox. In this review we will summarize the evidence regarding sex differences in experimental animal models and, very specially, in patients suffering from PAH or PH from other etiologies.

Adrenal steroids reference ranges in infancy determined by LC-MS/MS

BACKGROUND

Interpretation of the results of steroid hormone measurements is challenging at early infancy. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) method provides a powerful tool for diagnosing steroidogenesis disorders. We aimed to develop normative data for a 14-steroid panel and four adrenal enzyme activity indices, determined by LC-MS/MS from 3 days to 6 months of age.

METHODS

Age- and sex-specific plasma steroid concentrations were calculated in 324 healthy full-term neonates and infants (151 females). Percentile curves were devised. Steroid ratios were evaluated as biomarkers of adrenal enzyme activities. The steroid profiles of four patients with adrenal enzyme deficiencies were included to test the diagnostic efficiency.

RESULTS

Nine steroids showed age, but none showed sex specificity. The concentrations of progestins and androgens were higher at 7-14 days than at 3-7 days. After the first month, adrenal androgen concentrations decreased significantly. Adrenal enzyme activities changed towards increasing cortisol over the first 6 months. There were several-fold differences in diagnostic steroids and related adrenal enzyme activity indices between the patients and the healthy group.

CONCLUSIONS

The majority of adrenal steroids show age-related variations in the neonatal period and early infancy. Our data will enable accurate interpretation of steroid measurements for etiologic diagnosis of disorders of steroidogenesis.

IMPACT

LC-MS/MS method is capable of quantitating numerous analytes simultaneously, which provides an integrated picture of adrenal steroidogenesis in a small amount of sample. The development of LC-MS/MS-based normative data of steroid hormones in healthy infants is crucial to differentiate physiologic alterations from steroidogenic defects during the first 3-6 months of infancy. Previous studies had limitations due to the small numbers of samples available by sex and by age groups. Our detailed normative data and percentile curves will enable accurate interpretation of steroid measurements for etiologic diagnosis of disorders of steroidogenesis without the need for further invasive testing.

Diurnal salivary androstenedione and 17-hydroxyprogesterone levels in healthy volunteers for monitoring treatment efficacy of patients with congenital adrenal hyperplasia

OBJECTIVE

Treatment of congenital adrenal hyperplasia (CAH) patients with glucocorticoids is often challenging since there is a delicate balance between over- and undertreatment. Treatment can be monitored noninvasively by measuring salivary androstenedione (A4) and 17-hydroxyprogesterone (17-OHP). Optimal treatment monitoring requires the establishment of reference values in saliva.

DESIGN

A descriptive study.

PATIENTS

For this study saliva of 255 healthy paediatric and adult volunteers with an age range of 4-75 years old was used.

MEASUREMENTS

We developed a sensitive liquid chromatography-tandem mass spectrometry method, assessed salivary A4 and 17-OHP stability, and measured A4 and 17-OHP concentrations in saliva collected in the morning, afternoon, and evening.

RESULTS

We quantified A4 and 17-OHP concentrations in the morning, afternoon, and evening and demonstrated that there is a significant rhythm with the highest levels in the morning and decreasing levels over the day. A4 and 17-OHP concentrations display an age-dependent pattern. These steroids remain stable in saliva at ambient temperature for up to 5 days.

CONCLUSIONS

Good stability of the steroids in saliva enables saliva collection by the patient at home. Since salivary A4 and 17-OHP display a diurnal rhythm and age-dependent pattern, we established reference values for both children and adults at three time points during the day. These reference values support treatment monitoring of children and adults with CAH.

Genotype, Mortality, Morbidity, and Outcomes of 3β-Hydroxysteroid Dehydrogenase Deficiency in Algeria

Background

3β-hydroxysteroid dehydrogenase 2 (3βHSD2) deficiency is a rare form of congenital adrenal hyperplasia (CAH), with fewer than 200 cases reported in the world literature and few data on outcomes.

Patients and Methods

We report a mixed longitudinal and cross-sectional study from a single Algerian center between 2007 and 2021. Virilization and under-masculinization were assessed using Prader staging and the external masculinization score (EMS), pubertal development staged according to the system of Tanner. Adrenal steroids were measured using mass spectrophotometry (LC-MS/MS). A genetic analysis of HSD3B2 was performed using Sanger sequencing.

Results

A 3βHSD2 defect was confirmed in 6 males and 8 females from 10 families (8 consanguineous), with p.Pro222Gln mutation in all but two siblings with a novel deletion: c.453_464del or p.(Thr152_Pro155del). Probable 3βHSD2 deficiency was diagnosed retrospectively in a further 6 siblings who died, and in two patients from two other centers. In the genetically confirmed patients, the median (range) age at presentation was 20 (0-390) days, with salt-wasting (n = 14) and genital anomaly (n = 10). The Prader stage for female patients was 2 (1-2) with no posterior fusion of the labia. The EMS for males was 6 (3-9). Median (range) values at diagnosis for 17-hydroxyprogesterone (17-OHP), dehydroepiandrosterone sulfate (DHEA-S), and 17-hydroxypregnenolone (17OHPreg) were elevated: 73.7 (0.37-164.3) nmol/L; 501.2(9.4-5441.3) nmol/L, and 139.7 (10.9-1500) nmol/l (NB >90 nmol/L diagnostic of 3βHSD2 defect). Premature pubarche was observed in four patients (3F:1M). Six patients (5F:1M) entered puberty spontaneously, aged 11 (5-13) years in 5 girls and 11.5 years in one boy. Testicular adrenal rest tumors were found in three boys. Four girls reached menarche at 14.3 (11-14.5) years, with three developing adrenal masses (surgically excised in two) and polycystic ovary syndrome (PCOS), with radiological evidence of ovarian adrenal rest tumor in one. The median IQ was 90 (43-105), >100 in only two patients and <70 in three.

Conclusions

The prevalence of 3βHSD2 deficiency in Algeria appears high, with p.Pro222Gln being the most frequent mutation. Mortality is also high, with significant morbidity from adrenal tumors and PCOS in adolescence and an increased risk of learning disability. The finding of adrenal tumors in older patients with 3βHSD2 indicates under-replacement, requiring effective hydrocortisone and fludrocortisone treatment rather than surgical removal.

The Androstenedione Roche Elecsys immunoassay has superior comparability to the LC-MS/MS assay than the Siemens Immulite immunoassay

Androstenedione (ASD) is a biomarker used in the diagnostic workup of hyperandrogenism, congenital adrenal hyperplasia, premature adrenarche, and polycystic ovary syndrome (PCOS). The Elecsys ASD competitive electrochemiluminescence immunoassay (Roche Diagnostics, Indianapolis, IN) is a new assay recently available in the US.

Objective

This study evaluated the analytical and clinical performance of the Elecsys ASD assay.

Design & Methods

We evaluated the linearity/analytical measuring range (AMR), precision, and accuracy of the Elecsys ASD assay on the cobas e601 analyzer. ASD was measured in serum/plasma in the Elecsys ASD, Immulite (Siemens Medical Solutions USA, Inc. Malvern, PA), and LC-MS/MS assays. Reference intervals (RI) were evaluated across genders, menopausal status, and in children. Statistical analysis was performed using EP evaluator and R program.

Results

The Elecsys ASD assay had a linear response across the AMR. The intra- and inter-assay coefficients of variation at various concentrations were ≤4.5%. The Elecsys ASD assay had a mean difference of −0.04 ng/mL (−1.7%) with the LC-MS/MS assay, whereas the Immulite assay had a mean difference of 1.17 ng/mL (66%) and −1.22 ng/mL (−38%) compared to the LC-MS/MS and Elecsys ASD assays, respectively. The Roche recommended RIs for healthy men (0.280–1.52 ng/mL) and postmenopausal women (0.187–1.07 ng/mL) were successfully verified. The RIs for children were adopted from published data. For pre-menopausal women, a RI of <1.60 ng/mL was established. The ASD concentrations in women with and without PCOS overlapped.

Conclusions

The Elecsys ASD assay has superior comparability to the LC-MS/MS assay than the Immulite assay.

•

This study evaluated the analytical and clinical performance of the Roche Elecsys androstenedione assay, and compared to the Siemens Immulite assay and an LC-MS/MS assay.

•

The Roche Elecsys androstenedione assay has superior comparability to the LC-MS/MS assay than the Siemens Immulite assay.

•

We were unable to verify all the reference intervals provided by the manufacturer, highlighting the need of laboratories to assess and verify manufacturer-provided intervals.

Review of the Use of Liquid Chromatography-Tandem Mass Spectrometry in Clinical Laboratories: Part I-Development

The process of method development for a diagnostic assay based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) involves several disparate technologies and specialties. Additionally, method development details are typically not disclosed in journal publications. Method developers may need to search widely for pertinent information on their assay(s). This review summarizes the current practices and procedures in method development. Additionally, it probes aspects of method development that are generally not discussed, such as how exactly to calibrate an assay or where to place quality controls, using examples from the literature. This review intends to provide a comprehensive resource and induce critical thinking around the experiments for and execution of developing a clinically meaningful LC-MS/MS assay.

Rapid quantitative analysis of hormones in serum by multilayer paper spray MS: Free MS from HPLC

Developing rapid and reliable method for simultaneous hormones quantitation is of great significant because of important roles of hormones in metabolism. However, current methods are faced with problems of low throughput or complicated operation procedure to remove matrices from serum samples in routine clinical diagnosis. In the present work, a multilayer PS-MS method was developed for rapid and simple detection of hormones. In the strategy, multilayer filter paper acted as the Liquid Chromatography in LC-MS/MS for separation of hormones and biological matrices. Qualitative and quantitative analysis of three hormones, testosterone (T), androsterone (ADT) and androstenedione (4-AD) were realized through MS/MS spectra. The method exhibited linearity in the range of 0.02-2 μg/L and the results of recovery and repeatability were satisfactory for standard samples and spiked serum. The time-cost of a whole detection process was less than 3 min. The established multilayer PS-MS realized rapid, simple and reliable quantitative analysis of various hormones and provided broad prospect for clinical analysis of small molecules in different biological samples. Moreover, it provides a novel MS approach with high through-put and free HPLC, meeting the requirements of point-of-care testing (POCT).

The simultaneous quantitative detection of multiple hormones based on PS-MS: affinity capture by a single antibody

Here, we utilized single antibody to capture and separate multiple hormones from samples to avoid LC procedures and MS/MS detection to realize simultaneously qualitative and quantitative analysis of multiple molecules in a single run.

Distribution of androgen receptor mRNA in the prepubertal male and female mouse brain

Androgens are steroid hormones that play a critical role in brain development and sexual maturation by acting upon both androgen receptors (AR) and estrogen receptors (ERα/β) after aromatization. The contribution of estrogens from aromatized androgens in brain development and the central regulation of metabolism, reproduction, and behavior is well defined, but the role of androgens acting on AR has been unappreciated. Here, we map the sex specific expression of Ar in the adult and developing mouse brain. Postnatal days (PND) 12 and 21 were used to target a critical window of prepubertal development. Consistent with previous literature in adults, sex-specific differences in Ar expression were most profound in the bed nucleus of the stria terminalis (BST), medial amygdala (MEA) and medial preoptic area (MPO). Ar expression was also high in these areas at PND 12 and 21 in both sexes. In addition, we describe extra-hypothalamic and extra-limbic areas that show moderate, consistent and similar Ar expression in both sexes at both prepubertal time points. Briefly, Ar expression was observed in olfactory areas of the cerebral cortex, the hippocampus, several thalamic nuclei, and cranial nerve nuclei involved in autonomic sensory and motor function. To further characterize forebrain populations of Ar expressing neurons and determine whether they also coexpress estrogen receptors, we examined expression of Ar, Esr1 and Esr2 in prepubertal mice in selected nuclei. We found populations of neurons in the BST, MEA and MPO that coexpress Ar, but not Esr1 or Esr2, whereas others express a combination of the three receptors. Our findings indicate that various brain areas express Ar during prepubertal development and may play an important role in female neuronal development and physiology.

Normal and Premature Adrenarche

Adrenarche is the maturational increase in adrenal androgen production that normally begins in early childhood. It results from changes in the secretory response to adrenocorticotropin (ACTH) that are best indexed by dehydroepiandrosterone sulfate (DHEAS) rise. These changes are related to the development of the zona reticularis (ZR) and its unique gene/enzyme expression pattern of low 3ß-hydroxysteroid dehydrogenase type 2 with high cytochrome b5A, sulfotransferase 2A1, and 17ß-hydroxysteroid dehydrogenase type 5. Recently 11-ketotestosterone was identified as an important bioactive adrenarchal androgen. Birth weight, body growth, obesity, and prolactin are related to ZR development. Adrenarchal androgens normally contribute to the onset of sexual pubic hair (pubarche) and sebaceous and apocrine gland development. Premature adrenarche causes ≥90% of premature pubarche (PP). Its cause is unknown. Affected children have a significantly increased growth rate with proportionate bone age advancement that typically does not compromise growth potential. Serum DHEAS and testosterone levels increase to levels normal for early female puberty. It is associated with mildly increased risks for obesity, insulin resistance, and possibly mood disorder and polycystic ovary syndrome. Between 5% and 10% of PP is due to virilizing disorders, which are usually characterized by more rapid advancement of pubarche and compromise of adult height potential than premature adrenarche. Most cases are due to nonclassic congenital adrenal hyperplasia. Algorithms are presented for the differential diagnosis of PP. This review highlights recent advances in molecular genetic and developmental biologic understanding of ZR development and insights into adrenarche emanating from mass spectrometric steroid assays.

Multicenter Evaluation of a New, Fully Automated Androstenedione Electrochemiluminescence Immunoassay: Precision Analysis, Method Comparison, and Determination of Reference Ranges

BACKGROUND

Androstenedione (ASD) levels can aid diagnosis of hyperandrogenism together with other clinical/laboratory findings. We evaluated performance of the new, automated Elecsys® ASD assay vs an ASD isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) reference measurement procedure and determined reference ranges.

METHODS

Repeatability/intermediate precision were assessed using 3 control levels and 5 human serum pools (n = 75 each; Clinical and Laboratory Standards Institute EP05-A3). Method comparisons vs commercially available immunoassays [IMMULITE ASD (Siemens) and LIAISON ASD (DiaSorin)] and an ID-LC-MS/MS measurement procedure method were conducted using 421 serum samples; Passing-Bablok regression and Pearson's correlation coefficients were calculated. Reference ranges and distribution of values associated with polycystic ovary syndrome (PCOS) were determined in five clinical cohorts using samples from several sites/vendors.

RESULTS

Repeatability/intermediate precision coefficients of variation across all sites were 2.01% to 3.91% and 2.43% to 4.30%, respectively (mean ASD: 7.80-34.7 nmol/L). The Elecsys ASD assay showed poor agreement with IMMULITE ASD (slope = 0.459; r = 0.856; n = 320), fair agreement with LIAISON ASD (slope = 0.625; r = 0.984; n = 327), and very good agreement with ID-LC-MS/MS (slope = 1.040; r = 0.996; n = 332). Reference ranges (2.5th-97.5th percentiles) were: children (≤8 years; n = 140), <0.525 to 1.81 nmol/L; males (≥18 years; n = 138), 0.979 to 5.32 nmol/L; and postmenopausal females (n = 140), 0.654 to 3.74 nmol/L. Reference range (5th-95th percentiles) for females with fertile cycle (≥18 years; n = 84) was 1.71 to 4.58 nmol/L. The distribution of values (2.5th-97.5th percentiles) in females with PCOS (n = 125) was 2.26 to 12.1 nmol/L.

CONCLUSIONS

Elecsys ASD assay demonstrated excellent precision and very good agreement with ID-LC-MS/MS. Reference ranges were established to support results interpretation in routine practice.

Using mass spectrometry to overcome the longstanding inaccuracy of a commercially-available clinical testosterone immunoassay

Accurate measurement of testosterone is important for the diagnosis of gonadal disorders in men, women, and children. Testosterone measurement has limited accuracy at low concentrations by most commercially available immunoassays. We aimed to develop an LC-MS/MS assay to address the inaccuracy of the in-house immunoassay observed over the past decade and to replace it with the new assay. Testosterone in serum/plasma was extracted with commercial supported liquid extraction plates. Method validation was performed following the CLSI C62-A guideline. A total of 126 samples were used for method comparison between the Beckman UniCel DxI immunoassay and LC-MS/MS. Results by immunoassay were 20% lower compared with LC-MS/MS and had minimal correlation (R² = 0.403) with LC-MS/MS below 100 ng/dL. When comparing specimens from the Accuracy-Based Survey from the College of American Pathologists, the newly developed assay agreed well with the CDC reference measurement procedure. In summary, immunoassay measurement of testosterone can be significantly inaccurate, especially at low concentrations. The newly developed LC-MS/MS assay provides accurate results across the entire measurable range.

Progress and Challenges in Quantifying Carbonyl-Metabolomic Phenomes with LC-MS/MS

Carbonyl-containing metabolites widely exist in biological samples and have important physiological functions. Thus, accurate and sensitive quantitative analysis of carbonyl-containing metabolites is crucial to provide insight into metabolic pathways as well as disease mechanisms. Although reversed phase liquid chromatography electrospray ionization mass spectrometry (RPLC-ESI-MS) is widely used due to the powerful separation capability of RPLC and high specificity and sensitivity of MS, but it is often challenging to directly analyze carbonyl-containing metabolites using RPLC-ESI-MS due to the poor ionization efficiency of neutral carbonyl groups in ESI. Modification of carbonyl-containing metabolites by a chemical derivatization strategy can overcome the obstacle of sensitivity; however, it is insufficient to achieve accurate quantification due to instrument drift and matrix effects. The emergence of stable isotope-coded derivatization (ICD) provides a good solution to the problems encountered above. Thus, LC-MS methods that utilize ICD have been applied in metabolomics including quantitative targeted analysis and untargeted profiling analysis. In addition, ICD makes multiplex or multichannel submetabolome analysis possible, which not only reduces instrument running time but also avoids the variation of MS response. In this review, representative derivatization reagents and typical applications in absolute quantification and submetabolome profiling are discussed to highlight the superiority of the ICD strategy for detection of carbonyl-containing metabolites.

Female-dominant estrogen production in healthy children before adrenarche

OBJECTIVE

Ultra-sensitive hormone assays have detected slight sex differences in blood estradiol (E2) levels in young children before adrenarche. However, the origin of circulating E2 in these individuals remains unknown. This study aimed to clarify how E2 is produced in young girls before adrenarche.

DESIGN

This is a satellite project of the Japan Environment and Children's Study organized by the National Institute for Environmental Studies.

METHODS

We collected blood samples from healthy 6-year-old Japanese children (79 boys and 71 girls). Hormone measurements and data analysis were performed in the National Institute for Environmental Studies and the Medical Support Center of the Japan Environment and Children's Study, respectively.

RESULTS

E2 and follicle stimulating hormone (FSH) levels were significantly higher in girls than in boys, while dehydroepiandrosterone sulfate (DHEA-S) and testosterone levels were comparable between the two groups. Girls showed significantly higher E2/testosterone ratios than boys. In children of both sexes, a correlation was observed between E2 and testosterone levels and between testosterone and DHEA-S levels. Moreover, E2 levels were correlated with FSH levels only in girls.

CONCLUSIONS

The results indicate that in 6-year-old girls, circulating E2 is produced primarily in the ovary from adrenal steroids through FSH-induced aromatase upregulation. This study provides evidence that female-dominant E2 production starts several months or years before adrenarche. The biological significance of E2 biosynthesis in these young children needs to be clarified in future studies.

Challenging the binary: Gender/sex and the bio-logics of normalcy

BACKGROUND

We are witnessing renewed debates regarding definitions and boundaries of human gender/sex, where lines of genetics, gonadal hormones, and secondary sex characteristics are drawn to defend strict binary categorizations, with attendant implications for the acceptability and limits of gender identity and diversity.

AIMS

Many argue for the need to recognize the entanglement of gender/sex in humans and the myriad ways that gender experience becomes biology; translating this theory into practice in human biology research is essential. Biological anthropology is well poised to contribute to these societal conversations and debates. To do this effectively, a reconsideration of our own conceptions of gender/sex, gender identity, and sexuality is necessary.

METHODS

In this article, we discuss biological variation associated with gender/sex and propose ways forward to ensure we are engaging with gender/sex diversity. We base our analysis in the concept of "biological normalcy," which allows consideration of the relationships between statistical distributions and normative views. We address the problematic reliance on binary categories, the utilization of group means to represent typical biologies, and document ways in which binary norms reinforce stigma and inequality regarding gender/sex, gender identity, and sexuality.

DISCUSSION AND CONCLUSIONS

We conclude with guidelines and methodological suggestions for how to engage gender/sex and gender identity in research. Our goal is to contribute a framework that all human biologists can use, not just those who work with gender or sexually diverse populations. We hope that in bringing this perspective to bear in human biology, that novel ideas and applications will emerge from within our own discipline.

Exposure to Organophosphate and Neonicotinoid Insecticides and Its Association with Steroid Hormones among Male Reproductive-Age Farmworkers in Northern Thailand

Several studies indicated organophosphate (OP) and neonicotinoid (NEO) insecticides are endocrine disruptors; however, data are scarce. This cross-sectional study recruited 143 male farmworkers aged 18-40 years in Fang district, Chiang Mai province, northern Thailand. OP exposure was assessed by measuring urinary dialkylphosphate (DAPs) using a gas-chromatography flame photometric detector. Urinary NEOs, their metabolites (NEO/m) and serum steroid hormones were measured using liquid chromatography-tandem mass spectrometry. Characteristics of participants were determined by face-to-face interviews. DAPs and five NEO/m were detected in more than 60% of samples. The concentration of diethylphosphate was highest among DAP metabolites (geometric mean concentration (GM: 23.9 ng/mL) and the concentration of imidacloprid (IMI) was highest among NEO/m (GM: 17.4 ng/mL). Linear regression models showed that the IMI level was positively associated with testosterone, dehydrocorticosterone (DHC) and dehydroepiandrosterone (DHEA) levels. Imidacloprid-olefin and DHEA levels were positively associated. Thiamethoxam (THX) were inversely associated with DHC and deoxycorticosterone levels. Clothianidin (CLO), THX and N-desmethyl-acetamiprid levels were positively associated with the androstenedione level. CLO and THX levels were inversely associated with the cortisone level. In conclusion, the association between NEO insecticides exposure and adrenal androgens, glucocorticoids and mineralocorticoids, suggest potential steroidogenesis activities. Our findings warrant further investigation.

Concentrations of nine endogenous steroid hormones in 70-year-old men and women

OBJECTIVES

Circulating concentrations of endogenous steroids have systemic implications on health in elderly. However, population-based age- and ethnicity-specific data are scarce. The aim was to report sex-specific plasma concentrations of endogenous sex and adrenal steroids in elderly Swedish Caucasians, to examine the impact of BMI and to present concentrations in apparently healthy subjects.

METHODS

A population-based observational study of 70-year olds, including 684 community-dwelling men and women enrolled in the PIVUS study, Sweden. Median plasma concentrations were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for pregnenolone, 17-hydroxypregnenolone, 17-hydroxy-progesterone, 11-deoxycortisol, DHEA, androstenedione, testosterone, estrone and estradiol.

RESULTS

Plasma concentrations were significantly higher in men (n = 452) than in women (n = 232) for estradiol: median 61.3 pmol/L (95% CI, 11.4, 142.7) vs 18.4 (4.0, 127.3), for estrone: 92.8 (33.3, 206) vs 71.6 (17.8, 209) pmol/L, and for testosterone 13.8 (5.7, 28.0) vs 0.7 (0.2, 2.0) nmol/L. Higher concentrations of estrone and estradiol were observed in obese than non-obese women. Compared to non-obese men, obese men had lower concentrations of testosterone and its precursors: 17-hydroxypregnenolone, 17-hydroxyprogesterone, androstenedione and DHEA. The subgroup of apparently healthy individuals had median values > 20% lower for estrone and estradiol in women but slightly higher for testosterone in both sexes.

CONCLUSIONS

Concentrations of estradiol, estrone and testosterone were higher in 70-year-old men than in women. BMI associated positively to estradiol and estrone in women and negatively to testosterone in men. Apparently healthy women had lower median concentrations of estradiol and estrone and men had higher median testosterone compared to all individuals.

Biomarkers of Senescence during Aging as Possible Warnings to Use Preventive Measures

Human life expectancy is increasing significantly over time thanks to the improved possibility for people to take care of themselves and the higher availability of food, drugs, hygiene, services, and assistance. The increase in the average age of the population worldwide is, however, becoming a real concern, since aging is associated with the rapid increase in chronic inflammatory pathologies and degenerative diseases, very frequently dependent on senescent phenomena that occur alongside with senescence. Therefore, the search for reliable biomarkers that can diagnose the possible onset or predict the risk of developing a disease associated with aging is a crucial target of current medicine. In this review, we construct a synopsis of the main addressable biomarkers to study the development of aging and the associated ailments.

Quantification of BNN27, a novel neuroprotective 17-spiroepoxy dehydroepiandrosterone derivative in the blood and retina of rodents, after single intraperitoneal administration

BNN27 is a novel 17‐spiroepoxy derivative of the neurosteroid Dehydroepiandrosterone with neuroprotective properties. The purpose of this study was the detection and quantification of BNN27 after single intraperitoneal administration, in the serum and retina of normal rodents. Forty‐two C57BL/6 mice and 48 Sprague–Dawley rats were used for the quantification of BNN27 in the blood serum and retina, respectively. BNN27 was injected intraperitoneally (i.p.) at concentrations of 100 and 30 mg/kg of body weight (b.w.), respectively. The blood was collected with retro‐orbital bleeding and the retina was isolated after enucleation at various time points. The molecule concentrations were measured with Liquid chromatography‐mass spectrometry (LC‐MS). Non‐compartmental analysis was used to determine pharmacokinetic parameters. BNN27 was found to have an elimination constant k_el = 0.465 h⁻¹ and mean residence time (MRT) 2.154 h in the mouse serum. The maximum concentration (C_max) in the retina was detected at 2 h (tCmax) after intraperitoneal administration and was equal to 1100 ng/g. BNN27 is rapidly eliminated from both blood and retina. In the retina specifically, it is undetectable 6 h after injection. BNN27 shows a rapid systemic elimination as anticipated by its small size and lipophilicity. It is measurable in small peripheral tissues such as the rat retina, after one single i.p. injection, using a simple method such as LC‐MS. Its detection in the retina corroborates the existing biological data that the molecule crosses the blood–retinal barrier, highlighting it as a potential neuroprotective agent for retinal disease.

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 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.

Contrasting impact of androgens on male and female adiposity, fat distribution and insulin resistance in childhood and adolescence (EarlyBird 75)

OBJECTIVES

To investigate associations between androgens (testosterone, dehydroepiandrosterone sulphate [DHEAS] and androstenedione), adiposity, fat distribution and insulin resistance (IR) during childhood and adolescence.

METHODS

Three hundred and seven children (170 [55.4%] boys; 137 [44.6%] girls) recruited at age 5 and studied annually until age 16: androgens (liquid chromatography tandem-mass spectrometry), anthropometry, body composition (dual-energy x-ray absorptiometry) and IR (homeostasis model assessment).

RESULTS

Early adiposity was associated with earlier detection of androstenedione in both sexes, and DHEAS in boys. At puberty, higher androgen levels were associated with favourable metabolic changes in boys, but adverse metabolic effects in girls. In boys, higher free testosterone (FT) was associated with lower body fat and android/gynoid fat ratio (AGR) (both P < .001), but in girls higher total testosterone was associated with higher AGR. In girls only, higher androstenedione (P = .02) and FT (P = .01) was associated with higher IR during puberty.

CONCLUSIONS

In pre-pubertal children, adiposity is associated with higher secretion of androgen precursors. After pubertal onset, higher testosterone is associated with lower adiposity and AGR in boys, but higher AGR and IR in girls. Therefore, androgens have modest sex-specific associations with children's total body fat, fat distribution and IR.

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.