A UHPLC-MS/MS method for profiling multifunctional steroids in human hair

The determination of endogenous steroids in hair and fur: A systematic review of methodologies

BACKGROUND

Endogenous steroid hormone assessment is essential for clinical practice. These hormones are typically measured in blood. More recently, measurement of steroids in hair samples has been gaining in popularity, so we have reviewed the methodologies used for this to-date.

METHODS

Ovid Medline, CINAHL, Psychinfo, and EMBASE were searched to identify manuscripts that analysed cortisol, testosterone, androstenedione, 17-hydroxyprogesterone (17OHP), dehydroepiandrosterone sulphate (DHEAS), and/or 25-hydroxyvitamin D (25(OH)D), in hair or fur. Data related to sampling and measurement procedures were extracted and analysed.

RESULTS

The systematic review included a total of 180 papers, with 82 % published in the past 8 years; 67 % were human and 33 % animal studies. Cortisol was by far the most common analyte. Incomplete reporting on sample harvest, preparation, and measurement procedures was common. Typically, samples were collected from posterior vertex of humans or back/neck of animals, weighing between 11 and 50 mg (with a range of 1.25-1000 mg). Samples were usually stored at room temperature, often using aluminium foil. Isopropanol was the most common cleaning solution. Hair was normally powdered or segmented prior to extraction. Extraction was typically carried out over 18-24 hours using methanol. Validation and precision information was provided in 47 % of studies.

CONCLUSIONS

This systematic review highlights the lack of standardisation in the analysis of endogenous steroids in hair. Reporting was typically incomplete, and assay validations were partial or absent. Together, these limit the value of these exciting new methods and hold back transition to clinical use.

Glucocorticoids and mineralocorticoids in hair: facilitating accurate diagnosis of adrenal-related endocrine disorders

Background

Glucocorticoids and androgens in the hair follicle have been of interest for many years, particularly cortisol and cortisone in retrospective studies associated with chronic stress and Cushing's syndrome. No studies have reported aldosterone or 18-hydroxycorticosterone in the adrenal mineralocorticoid panel in the hair follicle. This study aimed to identify potential biomarkers in endocrine conditions associated with steroid excess or deficiency using a novel extraction protocol in the analysis of mineralocorticoids and glucocorticoids in the hair follicle.

Methods and findings

Hair was collected from 15 healthy male and female volunteers. Segments that were cut along the length of long, medium, and short hair and segments shaved on the scalp and the cheek were prepared for analysis. Hair samples were extracted using an automated accelerated solvent extraction (ASE) system. Steroids were analyzed using high-throughput ultra-performance convergence chromatography-tandem mass spectrometry. All mineralocorticoids and glucocorticoids were detected above the lower limit of quantification and none of the steroids differed statistically comparing male and female concentrations. Deoxycortisol, deoxycorticosterone, and aldosterone were detected for the first time in men. In both genders, 18-hydroxycortisosterone was detected for the first time. The median concentrations for women and men, respectively, were as follows: deoxycortisol, 14.2 and 19.2 pg/mg; cortisol, 34.7 and 33.9 pg/mg; cortisone, 22.4 and 22.0 pg/mg; deoxycorticosterone, 83.0 and 50.2 pg/mg; corticosterone, 10.9 and 11.5 pg/mg; 18-hydroxycorticosterone, 24.8 and 24.8 pg/mg; and aldosterone, 23.4 and 22.7 pg/mg. Deoxycortisol and deoxycorticosterone showed marked fluctuation along the hair follicle in both genders and showed inter-individual variance. Conversely, cortisol, cortisone, corticosterone, 18-hydroxycortisosterone, and aldosterone did not fluctuate, with no inter-individual variance. Cortisol was 1.5-fold higher than cortisone in accordance with the circulatory cortisol/cortisone relationship.

Conclusions

The novel extraction method optimized steroid measurement, showing the consistency of measurement for glucocorticoids, cortisol and cortisone, and mineralocorticoids, corticosterone, 18-hydroxycorticosterone, and aldosterone. Data suggest these steroids in the hair follicle to be ideal biomarkers in improving diagnostic testing, investigating conditions of steroid excess or deficiency in hypoaldosteronism, primary hyperaldosteronism, Cushing's syndrome, and the congenital adrenal hyperplasia subtypes.

A validated LC-MS/MS method for simultaneous determination of key glucocorticoids in animal hair for applications in conservation biology

A new method for the determination of main glucocorticoids (cortisol, cortisone, and corticosterone) in hair by liquid chromatography-tandem mass spectrometry was developed. Glucocorticoids were extracted from hair shafts using methanol followed by solid-phase extraction. A validation test was performed using hair from three species of wild mammals with different body size (0.2-800 kg), lifestyle (terrestrial, burrowing and arboreal species), social organization (living in herds or solitary), and different predicted type of hair glucocorticoids: European bison (Bison bonasus), European hamster (Cricetus cricetus), and Eurasian red squirrel (Sciurus vulgaris). Regardless of the species evaluated, the method shows good linearity for all analytes accompanied by satisfactory accuracy (91-114%) and precision (RSD < 13%). Depending on the analyte and hair origin, the calculated limits of quantification were between 0.05 and 1.19 ng/mL, which corresponds to 1.28-31.51 pg/mg. Using cortisol and cortisone as examples, we have demonstrated that measuring multiple glucocorticoids simultaneously provides more comprehensive information than solely concentrating on one, thereby contributing to a more balanced and reliable interpretation of the acquired results. However, the utility of cortisol metabolites as markers of stress response in keratinized tissues should be substantiated by additional experimental studies on targeted animals. We posit that this paper could serve as a crucial catalyst to prompt such experiments.

Towards a microfluidic H295R steroidogenesis assay-biocompatibility study and steroid detection on a thiol-ene-based chip

The development of cell-based microfluidic assays offers exciting new opportunities in toxicity testing, allowing for integration of new functionalities, automation, and high throughput in comparison to traditional well-plate assays. As endocrine disruption caused by environmental chemicals and pharmaceuticals represents a growing global health burden, the purpose of the current study was to contribute towards the miniaturization of the H295R steroidogenesis assay, from the well-plate to the microfluidic format. Microfluidic chip fabrication with the established well-plate material polystyrene (PS) is expensive and complicated; PDMS and thiol-ene were therefore tested as potential chip materials for microfluidic H295R cell culture, and evaluated in terms of cell attachment, cell viability, and steroid synthesis in the absence and presence of collagen surface modification. Additionally, spike-recovery experiments were performed, to investigate potential steroid adsorption to chip materials. Cell aggregation with poor steroid recoveries was observed for PDMS, while cells formed monolayer cultures on the thiol-ene chip material, with cell viability and steroid synthesis comparable to cells grown on a PS surface. As thiol-ene overall displayed more favorable properties for H295R cell culture, a microfluidic chip design and corresponding cell seeding procedure were successfully developed, achieving repeatable and uniform cell distribution in microfluidic channels. Finally, H295R perfusion culture on thiol-ene chips was investigated at different flow rates (20, 10, and 2.5 µL/min), and 13 steroids were detected in eluting cell medium over 48 h at the lowest flow rate. The presented work and results pave the way for a time-resolved microfluidic H295R steroidogenesis assay.

Simultaneous Quantification of Steroid Hormones Using hrLC-MS in Endocrine Tissues of Male Rats and Human Samples

Steroid hormones play a vital role in the regulation of cellular processes, and dysregulation of these metabolites can provoke or aggravate pathological issues, such as autoimmune diseases and cancer. Regulation of steroid hormones involves different organs and biological compartments. Therefore, it is important to accurately determine their levels in tissues and biofluids to monitor changes after challenge or during disease. In this work, we have developed and optimized the extraction and quantification of 11 key members of the different steroid classes, including androgens, estrogens, progestogens and corticoids. The assay consists of a liquid/liquid extraction step and subsequent quantification by high-resolution liquid chromatography coupled time-of-flight mass spectrometry. The recoveries range between 74.2 to 126.9% and 54.9 to 110.7%, using a cell culture or urine as matrix, respectively. In general, the signal intensity loss due to matrix effect is no more than 30%. The method has been tested in relevant steroidogenic tissues in rat models and it has also been tested in human urine samples. Overall, this assay measures 11 analytes simultaneously in 6 min runtime and it has been applied in adrenal gland, testis, prostate, brain and serum from rats, and urine and extracellular vesicles from humans.

Measurement of 7-dehydrocholesterol and cholesterol in hair can be used in the diagnosis of Smith-Lemli-Opitz syndrome

7-dehydrocholesterol (7-DHC) and cholesterol (CHOL) are biomarkers of Smith-Lemli-Opitz Syndrome (SLOS), a congenital autosomal recessive disorder characterized by elevated 7-DHC level in patients. Hair samples have been shown to have great diagnostic and research value, which has long been neglected in the SLOS field. In this study, we sought to investigate the feasibility of using hair for SLOS diagnosis. In the presence of antioxidants (2,6-ditert-butyl-4-methylphenol and triphenylphosphine), hair samples were completely pulverized and extracted by micro-pulverized extraction in alkaline solution or in n-hexane. After microwave-assisted derivatization with N,O-Bis(trimethylsilyl)trifluoroacetamide, the analytes were measured by GC-MS. We found that the limits of determination for 7-DHC and CHOL were 10 ng/mg and 8 ng/mg, respectively. In addition, good linearity was obtained in the range of 50-4000 ng/mg and 30-6000 ng/mg for 7-DHC and CHOL, respectively, which fully meets the requirement for SLOS diagnosis and related research. Finally, by applying the proposed method to real hair samples collected from 14 healthy infants and two suspected SLOS patients, we confirmed the feasibility of hair analysis as a diagnostic tool for SLOS. In conclusion, we present an optimized and validated analytical method for the simultaneous determination of two SLOS biomarkers using human hair.

Binding the gap between experiments, statistics, and method comparison: A tutorial for computing limits of detection and quantification in univariate calibration for complex samples

The present tutorial aims to review the most frequently reported criteria for the calculation of the limits of detection (LOD) and quantification (LOQ) in univariate calibration, summarizing their fundamentals, advantages, and limitations. The current criteria for estimating LOD and LOQ are based on diverse theoretical and/or empirical assumptions and require different amounts of experimental data, making the calculation rather complex in some cases. Moreover, alternative forms for calculating LOD/LOQ frequently lead to dissimilar results. This scenario might worsen in the case of complex analytical systems. Throughout this tutorial, different forms of calculating LOD/LOQ are illustrated using previously reported experimental datasets in the environmental chemistry field as examples. The influence of the sample matrix during the estimation of LOD/LOQ parameters is investigated through one calibration approache. The discrepancies in the obtained results with different criteria for the calculation of LOD/LOQ are highlighted. Finally, general guidelines and recommendations regarding experimental and data processing issues are proposed, aiming to promote fair criteria for the comparison of different analytical methodologies in terms of prediction ability and detection capability.

Profiling steroid and thyroid hormones with hair analysis in a cohort of women aged 25 to 45 years old

OBJECTIVE

Endogenous hormones regulate numerous physiological processes in humans. Some of them are routinely measured in blood, saliva and/or urine for the diagnosis of disorders. The analysis of fluids may, however, require multiple samples collected at different time points to avoid the high variability in the concentration of some hormones. In contrast, hair analysis has been proposed as an interesting alternative to reveal average hormone levels over a longer period. In this work, we developed and validated an analytical method for analyzing 36 endogenous steroid and thyroid hormones and one pineal hormone in human hair using ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS).

METHODS

Sample preparation involved hair decontamination, pulverization, methanol extraction, and purification with C18-solid phase extraction. Extracts were then divided into two portions, respectively injected into an UPLC-MS/MS system, and analyzed using two different instrumental methods. The method was applied to a healthy female population aged 25-45 years.

RESULTS

The method was validated on supplemented hair samples for the 37 targeted hormones, and its application to the population under study allowed to detect 32 compounds in 2-100% of the samples. Complete reference intervals (2.5-97.5th percentiles) were established for estrone, 17β-estradiol, androstenedione, dehydroepiandrosterone, progesterone, 17α-hydroxyprogesterone, cortisone, cortisol and 3,3',5-triiodo-L-thyronine. Hair cortisone, cortisol, tetrahydrocortisone and tetrahydrocortisol concentrations were highly correlated with each other, with Kendall's τ correlation coefficients ranging from 0.52 to 0.68.

CONCLUSION

Allowing the detection of 32 hormones from different chemical classes, the present method will allow to broaden hormonal profiling for better identifying endocrine disorders.

Nail Melatonin Content: A Suitable Non-Invasive Marker of Melatonin Production

Melatonin plays multiple physiological roles in the human body. Evaluation of melatonin production by the determination of urinary 6-sulfatoxymelatonin in 24-h samples has important drawbacks which hinder the successful evaluation of melatonin production in large cohorts. Here, we evaluated the potential of nail analysis for estimating melatonin production. Firstly, mass spectrometry methodology for the determination of melatonin in nails was optimized and successfully validated. The method was found to be linear in the range 6.5-830 fg/mg with intraday and interday accuracy in the range 100-104 %, precision below 15 % and a LOD of 3.5 fg/mg. Secondly, nail melatonin concentrations from 84 volunteers (age 5-96) were determined. The expected correlation between melatonin and age was obtained (correlation coefficient -0.615; p < 0.001). Additionally, we showed that fingernails are preferable to toenails to determine nail melatonin content. Finally, fingernails collected for 180 days after melatonin administration (two volunteers, 1.9 mg/night during 5 days) were analyzed. Nail melatonin concentrations immediately rose after administration and went back to pre-administration values after ≈100 days in both volunteers. Our results suggest that melatonin determination in nails is a suitable non-invasive tool for the estimation of global melatonin production. Due to the easy collection and storage of nails, the long-term information obtained and the multiple functions of melatonin, nail melatonin content might complement dim light melatonin onset, which is commonly measured from plasma/saliva samples, paving the way for melatonin research.

[Determination of sex steroids in shed skin of the beaded lizard Heloderma suspectum ("Gila Monster")]

OBJECTIVE

Measurement of steroid hormones in skin appendages such as mammalian hair or claws and in avian feathers represents a recognized non-invasive method for the determination of these parameters. The aim of this pilot study in the Gila Monster was to investigate whether the measurement of sex steroids in shed skin may be employed for the monitoring of endocrine gonadal function or sex determination in reptiles.

MATERIAL AND METHODS

Shed skins were available from 11 female and 7 male adult and sexually mature animals. Large pieces of skin were initially cut into smaller pieces with scissors. The resultant dermal fragments were finely ground under liquid nitrogen and finally extracted with organic solvents. The following parameters were determined radioimmunologically in the dried and re-dissolved extracts: progesterone (P4), estradiol-17β (E2), testosterone (T), free total estrogens (fGÖ) and free plus conjugated total estrogens (fkGÖ).

RESULTS

For P4 (p = 0.0052) and E2 (p = 0.0079) significant sex differences were found with higher concentrations in females compared to males. Unexpectedly, the measured values for T were also significantly higher in females (p = 0.0232) than in males, with the concentrations overall only slightly above the detection limit. Compared to fGÖ, the concentrations of fkGÖ were only slightly higher, with no significant differences between both sexes.

CONCLUSION AND CLINICAL RELEVANCE

In this pilot study, the methods employed did not allow for reliable sex determination in individual animals, neither alone nor in combination, due to an overlap between the sexes. In principle, however, the measurement of sex steroids in shed skins could represent a useful method for non-invasive sex determination or endocrine gonadal function assessment in certain reptile species.

Lithium ion adduction enables UPLC-MS/MS-based analysis of multi-class 3-hydroxyl group-containing keto-steroids

Steroids that contain a 3-hydroxyl group (3-OH steroids) are widely distributed in nature. During analysis with ESI-MS, they easily become dehydrated while in the protonated form, resulting in the production of several precursor ions and leading to low sensitivity of detection. To address this analytical challenge, here, we developed a method for the quantitation of 3-OH steroids by LC-MS/MS coupled with post-column addition of lithium (Li) ions to the mobile phase. The Li ion has a high affinity for the keto group of steroids, stabilizing their structures during ionization and permitting detection of analytes exclusively as the lithiated form. This not only improved the intensities of the precursor ions, but also promoted the formation of typical lithiated fragment ions. This improvement made the quantitation by multiple reaction monitoring more sensitive and reliable, as evidenced by 1.53-188 times enhanced detection sensitivity of 13 steroids that contained at least one keto and two hydroxyl groups or one keto and one 5-olefinic double bond, among 16 different 3-OH steroids. We deployed our newly developed method for profiling steroids in mouse brain tissue and identified six steroids in one tissue sample. Among these, 16-hydroxyestrone, tetrahydrocorticosterone, and 17α-hydroxypregnenolone were detected for the first time in the mouse brain. In summary, the method described here enables the detection of lithiated steroids by LC-MS/MS, including three 3-OH steroids not previously reported in the mouse brain. We anticipate that this new method may allow the determination of 3-OH steroids in different brain regions.

Endogenous steroid hormones in hair: Investigations on different hair types, pigmentation effects and correlation to nails

Steroid hormone analysis is widely used in health- and stress-related research to get insights into various diseases and the adaption to stress. Hair analysis has been used as a tool for the long-term monitoring of these steroid hormones. In this study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous identification and quantification of seven steroid hormones (cortisone, cortisol, 11-deoxycortisol, androstenedione, 11-deoxycorticosterone, testosterone, progesterone) in hair. Cortisol, cortisone, androstenedione, testosterone and progesterone were detected and quantified in authentic hair samples of different individuals. Significantly higher concentrations for body hair were found for cortisone and testosterone compared to scalp hair. Furthermore, weak correlations for the majority of steroids between scalp and body hair indicate that body hair is not really suitable as alternative when scalp hair is not available. The influence of hair pigmentation was analyzed by comparing pigmented to non-pigmented hair of grey-haired individuals. The results showed no differences for cortisol, cortisone, androstenedione, testosterone and progesterone concentrations (p > 0.05) implying that hair pigmentation has not a strong effect on steroid hormone concentrations. Correlations between hair and nail steroid levels were also studied. Higher concentrations of cortisol and cortisone in hair were found compared to nails (p < 0.0001). No significant correlation for cortisone, cortisol, androstenedione, testosterone and progesterone concentrations were found between hair and nails. These results demonstrate that matrix-dependent value ranges for hair and nail steroid levels should be established and applied for interpretation.

Detection of biogenic amines in pet food ingredients by RP-HPLC with automated dansyl chloride derivatization

The detection of biogenic amines is of significant interest to the food industry, as they can be used as indicators of food spoilage and they are potentially toxic. Because of their importance, there is a need for automated methods suitable for industry use that can detect a wide range of biogenic amines at sufficient levels for food analysis. In this work, optimized conditions for the automated determination of biogenic amines (histamine, putrescine, cadaverine, spermine, spermidine, tyramine, and tryptamine) derivatized with dansyl chloride are presented. Limits of detection below 0.2 ppm were achieved for seven biogenic amines and percentage recoveries were between 80 and 109% for the seven analytes spiked into meat meal samples. The method is simple and compared well to an existing method for the detection of biogenic amines in pet food ingredients.