An LC/MS/MS method for analyzing the steroid metabolome with high accuracy and from small serum samples

Simultaneous Determination of Selected Steroids with Neuroactive Effects in Human Serum by Ultrahigh-Performance Liquid Chromatography-Tandem Mass Spectrometry

Neuroactive steroids are a group of steroid molecules that are involved in the regulation of functions of the nervous system. The nervous system is not only the site of their action, but their biosynthesis can also occur there. Neuroactive steroid levels depend not only on the physiological state of an individual (person's sex, age, diurnal variation, etc.), but they are also affected by various pathological processes in the nervous system (some neurological and psychiatric diseases or injuries), and new knowledge can be gained by monitoring these processes. The aim of our research was to develop and validate a comprehensive method for the simultaneous determination of selected steroids with neuroactive effects in human serum. The developed method enables high throughput and a sensitive quantitative analysis of nine neuroactive steroid substances (pregnenolone, progesterone, 5α-dihydroprogesterone, allopregnanolone, testosterone, 5α-dihydrotestosterone, androstenedione, dehydroepiandrosterone, and epiandrosterone) in 150 μL of human serum by ultrahigh-performance liquid chromatography with tandem mass spectrometry. The correlation coefficients above 0.999 indicated that the developed analytical procedure was linear in the range of 0.90 nmol/L to 28.46 μmol/L in human serum. The accuracy and precision of the method for all analytes ranged from 83 to 118% and from 0.9 to 14.1%, respectively. This described method could contribute to a deeper understanding of the pathophysiology of various diseases. Similarly, it can also be helpful in the search for new biomarkers and diagnostic options or therapeutic approaches.

High throughput LC-MS/MS method for steroid hormone analysis in rat liver and plasma - unraveling methodological challenges

Comprehensive reference data for steroid hormones are lacking in rat models, particularly for early developmental stages and unconventional matrices as the liver. Therefore, we developed and validated an enzymatic, solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantify a panel of 23 steroid hormones in liver and plasma from adult and neonatal rats. Our approach tackles methodological challenges, focusing on undesired byproducts associated with specific enzymatic treatment, and enables a thorough assessment of potential interferences in complex matrices by utilizing unstripped plasma and liver. We propose an optimized enzymatic hydrolysis protocol using a recombinant β-glucuronidase/sulfatase mix (BGS mix) to efficiently deconjugate steroid phase II conjugates. The streamlined sample preparation and high-throughput solid phase extraction in a 96-well plate significantly accelerate sample processing for complex matrices and alarge number of samples. We were able to achieve the necessary sensitivity for accurately measuring the target analytes, particularly estrogens, in small sample sizes of 5-20 mg of liver tissue and 100 μL of plasma. Through the analysis of liver and plasma samples from adult and neonatal rats, including both sexes, our study showed a novel set of steroid hormone reference intervals. This study provides a reliable diagnostic tool for the quantification of steroids in rat models and gives insight in liver and plasma-related steroid hormone dynamics at early developmental stages. In addition, the method covers several pathway intermediates and extend the list of steroid hormones to be investigated.

Proximity hybridization regulated dual-mode ratiometric biosensor for estriol detection in pregnancy serum

Sensitive and accurate determination of estriol level is vastly significant for the fetal growth and development. Herein, we constructed a dual-mode ratiometric biosensor for estriol assay combining the competitive immunoreaction, proximity hybridization with a two-step resonance energy transfer (RET) strategy. Estriol antibody and goat anti-rabbit antibody labeled DNA probes (Ab1-DNA1-Pt NPs and Ab2-DNA2) both hybridized with silver nanoclusters labeled DNA strands (H1-Ag NCs). Thus, the formed proximity hybridization enabled the occurrence of fluorescence RET (FL-RET, as the primary RET) between Ag NCs (donor) and Pt NPs (acceptor), quenching FL intensity of Ag NCs (FL off). When target estriol existed, the competitive reaction of Ab1-DNA1-Pt NPs with estriol and Ab2-DNA2 avoided the proximity hybridization. Then, the estriol-dependent H1-Ag NCs quenched electrochemiluminescence (ECL) emission of CdS quantum dots (CdS QDs, ECL off), generating ECL-RET (as the second RET). Consequently, according to the reverse changes of FL and ECL responses, this sensor realized the quantification of estriol from 1 to 100 ng/mL. Moreover, satisfactory results were achieved while testing estriol in pregnancy serum specimens, suggesting that the system is promising for potential application in samples analysis.

LC-MS/MS based quantification of steroidal biomarkers in polycystic ovary syndrome induced rats

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that causes reproductive hormones imbalance, missed periods, infertility and distributed steroidogenesis. Reportedly, during PCOS, the endogenous levels of P4 (Progesterone), 17OHP4 (17-α hydroxy progesterone), and T4 (Testosterone) were significantly altered. Thus, quantification of steroid biomarkers involved in the steroidogenesis pathway of PCOS, such as P4, 17OHP4, and T4, holds significant importance. One important drawback of current methods is steroid metabolome traceability. Without adequate traceability, the findings of these techniques will be less reliable for identifying P4, 17OHP4, and T4. These methods also need a high sample size, especially for the most important biomarker that initiates steroidogenesis. To address these challenges, we require a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for steroid biomarker analysis. Herein the present work, using validated LC-MS/MS, PCOS biomarkers were measured and compared between normal control rats and PCOS-induced rats before and after analyte administration. The experiment utilized an isocratic separation method employing an analytical C18 column. The mobile phase consisted of acetonitrile (ACN) and aqueous 0.1% formic acid (FA) in a ratio of 90:10 (v/v). The plasma samples were processed with protein precipitation (PPT) followed by the liquid-liquid extraction (LLE) method. The lower limit of quantification (LLOQ) was 0.5 ng/mL in plasma. According to USFDA criteria, the method's systematic validation took into account linearity (r2 > 0.99), accuracy and precision of intra- and inter-batch measurements, stability, biomarker recovery (60-85%) and matrix effect (<± 15%), all of which were determined to be within range ( ± 15%). The pharmacokinetic data showed that, as compared to normal rats, PCOS-induced animals had significantly higher Cmax values for 17OHP4 and T4 (∼2 fold), while lower Cmax values for P4 (∼2 fold). The present work is novel and provides scientific information to explore systematic processes involved in steroidogenesis and boost clinical applicability for PCOS therapy.

Sterol and lipid metabolism in bees

BACKGROUND

Bees provide essential pollination services for many food crops and are critical in supporting wild plant diversity. However, the dietary landscape of pollen food sources for social and solitary bees has changed because of agricultural intensification and habitat loss. For this reason, understanding the basic nutrient metabolism and meeting the nutritional needs of bees is becoming an urgent requirement for agriculture and conservation. We know that pollen is the principal source of dietary fat and sterols for pollinators, but a precise understanding of what the essential nutrients are and how much is needed is not yet clear. Sterols are key for producing the hormones that control development and may be present in cell membranes, where fatty-acid-containing species are important structural and signalling molecules (phospholipids) or to supply, store and distribute energy (glycerides).

AIM OF THE REVIEW

In this critical review, we examine the current general understanding of sterol and lipid metabolism of social and solitary bees from a variety of literature sources and discuss implications for bee health.

KEY SCIENTIFIC CONCEPTS OF REVIEW

We found that while eusocial bees are resilient to some dietary variation in sterol supply the scope for this is limited. The evidence of both de novo lipogenesis and a dietary need for particular fatty acids (FAs) shows that FA metabolism in insects is analogous to mammals but with distinct features. Bees rely on their dietary intake for essential sterols and lipids in a way that is dependent upon pollen availability.

Elevated follicular cortisone level is a negative predictor of clinical pregnancy in women undergoing fresh embryo transfer

Background

Although numerous studies have investigated the potential correlation between follicular fluid (FF) steroid concentrations and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes, few have accounted for the effect of controlled ovarian hyperstimulation regimes on FF steroid concentrations.

Objective

To comprehensively compare follicular steroid concentrations between women stimulated with gonadotropin-releasing hormone agonist (GnRHa) and antagonist (GnRHant) protocols and to explore the associations between FF steroid concentrations and IVF/ICSI outcomes.

Methods

A total of 295 infertile women undergoing IVF/ICSI from January 2018 to May 2020 were enrolled. Eighty-four and 211 women received GnRHa and GnRHant protocols, respectively. Seventeen steroids in FF were quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS), and the correlation of follicular steroids with clinical pregnancy was explored.

Results

Follicular steroid concentrations were similar between the GnRHa and GnRHant groups. Follicular cortisone levels were adversely associated with clinical pregnancy in fresh embryo transfers. Receiver operating characteristic (ROC) analysis revealed an area under the ROC curve (AUC) of 0.639 (95% confidence interval = 0.527-0.751, p = 0.025) for predicting non-pregnancy, with an optimal cutoff value of 15.81 ng/mL (sensitivity = 33.3%, specificity = 94.1%). Women with FF cortisone concentrations ≥15.81 ng/mL were fifty times less likely to achieve clinical pregnancy in fresh embryo transfers than those with FF cortisone levels below this threshold (adjusted OR = 0.019, 95% confidence interval = 0.002-0.207, p = 0.001) after adjusting for age, body mass index, baseline serum progesterone levels, serum levels of luteinizing hormone, estradiol and progesterone on human chorionic gonadotropin day, ovarian stimulation protocols, and the number of transferred embryos.

Conclusions

There was no significant difference in intrafollicular steroid levels between GnRHa and GnRHant protocols, and intrafollicular cortisone level ≥15.81 ng/mL was found to be a strong negative predictor of clinical pregnancy in fresh embryo transfers with high specificity.

Supercritical Fluid Chromatography Coupled to High-Resolution Mass Spectrometry Reveals Persistent Mobile Organic Compounds with Unknown Toxicity in Wastewater Effluents

Broad screening approaches for monitoring wastewater are normally based on reversed-phase liquid chromatography (LC) coupled to high-resolution mass spectrometry (HRMS). This method is not sufficient for the very polar micropollutants, neglected in the past due to a lack of suitable analytical methods. In this study, we used supercritical fluid chromatography (SFC) to detect very polar and yet-undetected micropollutants in wastewater effluents. We tentatively identified 85 compounds, whereas 18 have only rarely been detected and 11 have not previously been detected in wastewater effluents such as 17α-hydroxypregnenolone, a likely transformation product (TP) of steroids, and 1H-indole-3-carboxamide, a likely TP from new synthetic cannabinoids. Suspect screening of 25 effluent wastewater samples from 8 wastewater treatment plants revealed several distinct potential pollution sources such as a pharmaceutical company and a golf court. The analysis of the same samples with LC-HRMS showed clearly how SFC increases the ionization efficiency for low-molecular-weight micropollutants (m/z < 300 Da) by a factor 2 to 87 times, which significantly improved the mass spectra for identifying very polar compounds. In order to assess which micropollutants might be of environmental concern, literature and toxicological databases were screened. There was a lack of available hazard and bio-activity data for regulatory-relevant in vitro and in vivo assays for >50% of the micropollutants. Especially, 70% of the data were lacking for the whole organism (in vivo) tests.

Development of Fe3O4/reduced graphene oxide nanocomposite-based dispersive solid-phase extraction for the quantification of five steroid hormones

Aim: An accurate and sensitive analytical method was proposed to detect some steroid hormones in biological samples. Materials & methods: An Fe₃O₄/reduced graphene oxide nanocomposite-based dispersive solid-phase extraction was developed for the effective and simple preconcentration of steroid hormones from human serum samples. Results & conclusion: The nanocomposite was firstly used as adsorbent to simultaneously extract the selected hormones. Limit of detection values for the selected hormones were calculated between 5.5 and 39.2 ng/kg (mass based). An artificial serum sample was used to test the applicability and accuracy of the developed method; percentage recovery results obtained from two different spiked concentrations were found to be in the range of 80.5-99.9%.

A novel UPLC-ESI-MS assay for fifteen portal estrogens and metabolites detection and application in hepatic fibrosis

Estrogens and their metabolites (EMs) are involved in chronic liver disease and gut microbiota regulates estrogen metabolism, whereas the role of enterogenous EMs in liver disease is still elusive. Because of the extremely low level of EMs in portal serum and the EMs contain multiple pairs of isomers, an accurate determination of portal serum EMs is urgently needed. This study established a quantitative detection method for portal serum EMs and applied to non-alcoholic fatty liver disease (NAFLD) related hepatic fibrosis mice model. The serum was derived with a novel derivatization reagent 4-acetyl aminobenzene sulfonyl chloride, and a UPLC-ESI-MS system was used for quantification of 15 EMs in 120 min. Compared with normal group, the concentrations of E1, E2 in model group were significantly decreased by 4-8 times, all the C2 and C4 substitution products (2-OHE1, 2-OHE2, 2-MeOE1, 4-OHE1, 4-MeOE1, 4-OHE2, 4-MeOE2, 2-MeOE2) were significantly decreased by 2-22 times. However, the C16 and C17 substitution products (E3, 16-epiE3, 17-epiE3, 16-ketoE2) levels were increased by 3-5 times (P < 0.01). This study elucidated the changes of enterogenous EMs which entered the liver via portal vein in NAFLD - related hepatic fibrosis and provided methodological platform for other related studies on estrogen metabolism.

Steroid Profiling for the Diagnosis of Congenital Adrenal Hyperplasia by Microbore Ultra-performance Liquid Chromatography-Tandem Mass Spectrometry

BACKGROUND

A rapid and accurate measurement approach for 17α-hydroxyprogesterone (17-OHP) and related steroids in amount/volume-limited clinic samples is of importance for precise newborn diagnosis of congenital adrenal hyperplasia (CAH) and its subtypes in clinic.

METHODS

Sixteen steroids (17-OHP, androstenedione, cortisol, tetrahydro-11-deoxycortisol, pregnenolone, progesterone, 11-deoxycorticosterone, corticosterone, 21-deoxycortisol, 11-deoxycortisol, dehydroepiandrosterone, testosterone, aldosterone, 17α-hydroxypregnenolone, dihydrotestosterone and 18-hydroxycorticosterone) were included in the panel of high-throughput microbore ultra-performance liquid chromatography-tandem mass spectrometry. Samples were collected from 126 normal subjects and 65 patients including different subtypes of CAH.

RESULTS

The method was validated with satisfactory analytical performance in linearity, repeatability, recovery and limit of detection. Reference intervals for 16 steroids were established by quantifying the level of steroids detected in normal infants. The applicability of the method was tested by differentiating steroid metabolic characteristics between normal infants and infants with CAH, as well as between infants with different CAH subtypes. The relevance of 17-OHP, 21-deoxycortisol, and 17-OHP/11-deoxycortisol for 21-hydroxylase deficiency screening was demonstrated. The level of 11-deoxycorticosterone, 11-deoxycortisol, progesterone and androstenedione can be used for the diagnosis of different rare subtypes of CAH.

CONCLUSION

This study provides a strategy for highly efficient steroid analysis of amount/volume-limited clinic samples and holds great potential for clinical diagnosis of CAH.

Sample multiplexing for increasing throughput for quantification of estrogens in serum by LC-MS/MS

Estrogens are involved in many physiological processes in vivo. The accurate and rapid quantification of estrogens is required for the diagnosis and prognosis of estrogen-related diseases. To achieve high-volume assays, we developed and validated a sample-multiplexing liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of serum estrogens including estrone (E1), estradiol (E2), and estriol (E3). A total of 100 μL serum samples were extracted using ethyl acetate. After derivatization with either dansyl chloride or pyridine-3-sulfonyl chloride, derivatized samples were combined. Then we performed the second liquid-liquid extraction using hexane to purify the mixture. Finally, the reconstitution solutions were injected into LC-MS/MS. In addition, the proposed LC-MS/MS method was validated according to FDA and CLSI guidelines. Within a single run (7 min), this sample-multiplexing LC-MS/MS method could simultaneously analyze E1, E2, and E3 in 2 serum samples. Meanwhile, the method demonstrated satisfactory analytical characteristics including accuracy (87.7-110.3%), linearity (2-1000 pg/mL, R² > 0.99), precision (intra-assay CV, 1.7-8.7%; inter-assay CV, 1.9-9.4%), and negligible interference and carry-over effect as well as acceptable matrix effect. In conclusion, this sample-multiplexing LC-MS/MS method has achieved a doubled-throughput assay for simultaneous quantification of E1, E2, and E3 without compromising analytical characteristics.

Rapid Derivatization of Phenolic and Oxime Hydroxyl with Isonicotinoyl Chloride under Aqueous Conditions and Its Application in LC-MS/MS Profiling Multiclass Steroids

Quantification of steroids possesses a crucial clinical value in early diagnosis and prognosis evaluation of various endocrine diseases. However, it is still challenging to realize feasible analysis of estrogens, androgens, progestogens, and corticoids within one single workflow. In this study, two derivatization reactions were newly designed for improvement: (1) acylation of phenolic hydroxyl on estrogens with isonicotinoyl chloride (INC) under the catalysis of 4-dimethylaminopyridine and (2) post-modification of oxime hydroxyl on hydroxylamine-pretreated ketosteroids with INC. Both reactions could conduct instantaneously at room temperature under aqueous conditions. Moreover, the resulting phenolic-INC and oxime-INC esters exhibited favorable MS responses. Through integrating these derivatization strategies with cold-induced phase separation technology, a feasible LC-MS/MS method was developed for simultaneous quantification of 15 multiclass steroids with proper sample consumption (50 μL serum), satisfying sensitivity (lower limit of quantitation at 0.01-5.00 ng/mL) and high throughput (40 min for sample-preparation). The practical applicability was tested by detecting 30 real samples from pregnant and non-pregnant women. The obtained results showed a good agreement with a previous validated methodology.

Validity of the association between five steroid hormones quantification and female infertility conditions: A new perspective for clinical diagnosis

Quantification of endogenous steroids and their precursors is essential for diagnosis of a wide range of causes for female infertility. However, immunoassays often overestimate concentrations due to assay interference by other endogenous steroids, especially at low concentrations. In addition, it still lacks of diagnostic reference intervals for five sex steroid hormones, including estradiol (E₂), 11-deoxycorticosterone (DOC), 17-hydroxyprogesterone (17-OHP₄), pregnenolone (P₅) and progesterone (P₄), which are crucial for distinguishing between normal individuals and female infertility. Therefore, we developed and validated a reliable and rapid ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneous determination and quantification of five sex hormones, giving the reference intervals to accurately evaluate and diagnose female infertility. Our results showed that the developed UPLC-MS/MS assay was fast, high throughput, reproducible, specific, accurate, highly sensitive, and fully validated for simultaneous determination of P₅, P₄, 17-OHP₄, DOC and E₂ in human follicular fluid. The simple sample preparation procedure in the current study gave reproducible and consistent recoveries. The validation results show that the UPLC-MS/MS assay has acceptable accuracy and precision at low concentrations, which permits their use in clinical study. In addition, our data gave the concentration range of five steroid hormones quantification in patients with female infertility and normal individuals. Our data can be used to accurately evaluate and diagnose female infertility.

GC-MS/MS Determination of Steroid Hormones in Urine Using Solid-Phase Derivatization as an Alternative to Conventional Methods

Solid-phase analytical derivatization (SPAD) is a promising hybrid sample preparation technique combining the clean-up and preconcentration of the sample in a single step. In this work, a novel SPAD method based on the preparation of trimethylsilyl (TMS) derivatives of steroid hormones (testosterone, estrone, DHT, estriol, estradiol, and progesterone) in Phenomenex Strata C18-E (100 mg, 1 mL) cartridges has been developed and applied for their GC-MS/MS determination in human urine samples. The proposed procedure allows the detection and quantification of steroids with limits of 1.0–2.5 and 2.5–5 ng/mL, respectively. These characteristics are comparable with those obtained with a conventional liquid–liquid extraction, while the recovery of analytes in the proposed SPAD procedure is higher. The major advantages of SPAD are a short derivatization time, high efficiency, and the possibility to automatize the procedure. However, its cost-effectiveness in routine practice is still questionable.

Multi-steroid profiling by UHPLC-MS/MS with post-column infusion of ammonium fluoride

BACKGROUND

Multi-steroid profiling is a powerful analytical tool that simultaneously quantifies steroids from different biosynthetic pathways. Here we present an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) assay for the profiling of 23 steroids using post-column infusion of ammonium fluoride.

METHODS

Following liquid-liquid extraction, steroids were chromatographically separated over 5 min using a Phenomenex Luna Omega C₁₈ column and a water (0.1 % formic acid) methanol gradient. Quantification was performed on a Waters Acquity UHPLC and Xevo® TQ-XS mass spectrometer. Ammonium fluoride (6 mmol/L, post-column infusion) and formic acid (0.1 % (vol/vol), mobile phase additive) were compared as additives to aid ionisation.

RESULTS

Post-column infusion of ammonium fluoride enhanced ionisation in a steroid structure-dependent fashion compared to formic acid (122-140 % for 3βOH-Δ5 steroids and 477-1274 % for 3-keto-Δ4 steroids). Therefore, we analytically validated post-column infusion of ammonium fluoride. Lower limits of quantification ranged from 0.3 to 3 nmol/L; All analytes were quantifiable with acceptable accuracy (bias range -14 % to 11.9 % for 21/23, -21 % to 11.9 % for all analytes). Average recovery ranged from 91.6 % to 113.6 % and average matrix effects from -29.9 % to 19.9 %. Imprecision ranged from 2.3 % to 23 % for all analytes and was < 15 % for 18/23 analytes. The serum multi-steroid profile of 10 healthy men and 10 healthy women was measured.

CONCLUSIONS

UHPLC-MS/MS with post-column infusion of ammonium fluoride enables comprehensive multi-steroid profiling through enhanced ionisation particularly benefiting the detection of 3-keto-Δ4 steroids.

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.

An LC-MS/MS Methodological Framework for Steroid Hormone Measurement from Human Serum

Estrogens and androgens are important regulators of sexual development and physiological processes in men and women, acting on numerous organs throughout the body. Moreover, they can contribute to a variety of pathologies, including osteoporosis, cancer, and cardiovascular and neurologic diseases. Analysis of estrogens and androgens in biological samples has been commonly performed using immunoassays for many years. However, these assays are suboptimal, as there is cross-reactivity with similar analytes, and they have moderate specificity and sensitivity. Thus, there is a clinical need to develop highly sensitive and specific methods for the accurate measurement of estrogen and androgen concentrations. Herein, we describe the development of three liquid chromatography coupled tandem mass spectrometry-based methods that incorporate the use of a Triple Quadrupole Mass Spectrometer for quantitative measurement of endogenous concentrations of various steroid hormones in human serum samples: (1) the simultaneous measurement of testosterone, androstenedione, and cortisol, (2) dehydroepiandrosterone (DHEA), and (3) 17β-estradiol (E₂). The use of derivatizing reagents, Girard's reagent P and dansyl chloride, allowed for significant gains in sensitivity in the analysis of DHEA and E2, respectively, relative to the underivatized analyte. These procedures proved efficient and adequately sensitive for steroid hormone analysis in extracted patient sera samples from older men and postmenopausal women, providing reliable data down to low nanogram/ml and sub-nanogram/ml levels. Moreover, utilizing the combination of highly specific mass transitions associated with these analytes and their respective internal deuterated standards provided a high degree of specificity to the identity of these hormones.

Metabolic Alteration Analysis of Steroid Hormones in Niemann-Pick Disease Type C Model Cell Using Liquid Chromatography/Tandem Mass Spectrometry

Niemann–Pick disease type C (NPC) is an autosomal recessive disease caused by a functional deficiency of cholesterol-transporting proteins in lysosomes, and exhibits various clinical symptoms. Since mitochondrial dysfunction in NPC has recently been reported, cholesterol catabolism to steroid hormones may consequently be impaired. In this study, we developed a comprehensive steroid hormone analysis method using liquid chromatography/tandem mass spectrometry (LC–MS/MS) and applied it to analyze changes in steroid hormone concentrations in NPC model cells. We investigated the analytical conditions for simultaneous LC–MS/MS analysis, which could be readily separated from each other and showed good reproducibility. The NPC phenotype was verified as an NPC model with mitochondrial abnormalities using filipin staining and organelle morphology observations. Steroid hormones in the cell suspension and cell culture medium were also analyzed. Steroid hormone analysis indicated that the levels of six steroid hormones were significantly decreased in the NPC model cell and culture medium compared to those in the wild-type cell and culture medium. These results indicate that some steroid hormones change during NPC pathophysiology and this change is accompanied by mitochondrial abnormalities.

Cold-induced phase separation for the simple and reliable extraction of sex hormones for subsequent LC-MS/MS analysis

Sex hormones, including androgens, estrogens, and progestogens, are important biomarkers for various diseases. Quantification of sex hormones is typically conducted by LC-MS/MS. At present, most methods require liquid-liquid extraction or solid phase extraction for sample preparation. However, these pretreatments are prone to compromise LC-MS/MS throughput. To improve on the current standard practices, we investigated cold-induced phase separation for sex hormone extraction. After protein precipitation with acetonitrile and adjusting the solution constitution with water, samples were stored at -30°C for 10 min to generate two distinct phases: an acetonitrile-rich layer on top of a water-rich layer. During this process, the hydrophobic sex hormones spontaneously separate into the upper layer. This simple and reliable cold-induced phase separation-based LC-MS/MS methodology was used here to simultaneously detect estrone, estradiol, estriol, testosterone, androstenedione, dehydroepiandrosterone, progesterone, and 17-hydroxyprogesterone in serum. Validation of this method indicated satisfactory performance, including acceptable linearity, accuracy, precision, and tractability. Compared with the mainstream liquid-liquid extraction-based method, this new method exhibits significant progress in throughput, which shortens the time cost of sample preparation from 90 to 40 min. We propose that this method can be an excellent alternative for sex hormone analysis in routine clinical laboratories.

Effect of maternal body mass index on the steroid profile in women with gestational diabetes mellitus

OBJECTIVE

To explore the effect of maternal body mass index (BMI) on steroid hormone profiles in women with gestational diabetes mellitus (GDM) and those with normal glucose tolerance (NGT).

METHODS

We enrolled 79 women with NGT and 80 women with GDM who had a gestational age of 24-28 weeks. The participants were grouped according to their BMI. We quantified 11 steroid hormones profiles by liquid chromatography-tandem mass spectrometry and calculated the product-to-precursor ratios in the steroidogenic pathway.

RESULTS

Women with GDM and BMI<25kg/m² showed higher concentrations of dehydroepiandrosterone (DHEA) (p<0.001), testosterone (T) (p=0.020), estrone (E1) (p=0.010) and estradiol (E2) (p=0.040) and lower Matsuda index and HOMA-β than women with NGT and BMI<25kg/m². In women with GDM, concentrations of E1 (p=0.006) and E2 (p=0.009) declined, accompanied by reduced E2/T (p=0.008) and E1/androstenedione (A4) (p=0.010) in the BMI>25 kg/m² group, when compared to that in the BMI<25 kg/m² group. The values of E2/T and E1/A4 were used to evaluate the cytochrome P450 aromatase enzyme activity in the steroidogenic pathway. Both aromatase activities negatively correlated with the maternal BMI and positively correlated with the Matsuda index in women with GDM.

CONCLUSIONS

NGT women and GDM women with normal weight presented with different steroid hormone profiles. Steroidogenic pathway profiling of sex hormones synthesis showed a significant increase in the production of DHEA, T, E1, and E2 in GDM women with normal weight. Additionally, the alteration of steroid hormone metabolism was related to maternal BMI in women with GDM, and GDM women with overweight showed reduced estrogen production and decreased insulin sensitivity compared with GDM women with normal weight.

A developed HPLC-MS/MS method to quantitate 5 steriod hormones in clinical human serum by using PBS as the surrogate matrix

Steroid hormones play an essential role in regulating physiological and reproductive development throughout the lifetime of an individual. One of the difficulties in determining endogenous substances is the lack of a blank matrix. Especially when the level of analytes is lower than the level in the so-called blank matrix. In the present study, an optimized HPLC-MS/MS method was developed and validated to quantify androstenedione (ASD), testosterone (Ts), dehydroepiandrosterone (DHEA), 5α-dihydrotestosterone (DHT), and progesterone (P) in serum samples from healthy people using PBS (pH = 7.4) as the blank surrogate matrix. Simultaneously, the method investigated the characteristics of NaCl, bull serum albumin, pure water as surrogate matrices for the analysis of steroid hormones. The data showed that the matrix effects of ASD, Ts, DHEA, DHT, and P in the same groups were not significantly different between PBS and twice charcoal-stripped serum (CS₂S) as a blank surrogate matrix. Furthermore, the LLOQ using PBS as the blank matrix was up to 0.005 ng/mL for ASD, Ts, and P and 0.05 ng/mL for DHEA and DHT. The reference ranges of concentration (C_PBS) of 5 steroid hormones were provided. Compared to the concentration with CS₂S (C_CSS) as the blank surrogate matrix, the relative biases (RBs) of Ts, DHT, P, and DHEA were finally stabilized at approximately -0.7%, -15%, -1.2%, and 9.2%, respectively. The results suggest that, in the cases of special required, the developed HPLC-MS/MS method can be used to determine the absolute concentration of 5 hormones in biological samples with PBS as the blank surrogate matrix.

Steroid profiling and genetic variants in Chinese women with gestational diabetes mellitus

Previous studies have demonstrated that steroids were associated with gestational diabetes mellitus (GDM). However, results from different studies remained inconsistent, and only a limited range of steroids were investigated in these studies. Therefore, we aimed to analyze comprehensive steroid profiling in Chinese women with GDM during third-trimester pregnancy. In 97 Chinese pregnant women, we measured steroid profile using a LC-MS/MS method, and calculated product-to-precursor ratios in metabolic pathways of steroids. Then sixteen genetic variants of genes encoding steroidogenic enzymes were genotyped by MassARRAY system. There were significant differences (P < 0.05) and obvious changes (fold change <0.67 or>1.5) in steroids (testosterone, estriol, pregnenolone and dehydroepiandrosterone) and product-to-precursor ratios (E2/T and T/AD) between GDM and control groups. After adjusting for maternal age, the TT genotype and T allele of CYP19A1 rs10046 were associated with an increased risk of GDM. And the CC genotype and C allele of HSD17B3 rs2257157 were also associated with an increased risk of GDM. Besides, pregnant women carrying TT genotype of CYP19A1 rs10046 and CC genotype of HSD17B3 rs2257157 had a lower E2/T ratio and higher T/AD ratio respectively comparing with those carrying other genotypes. In conclusion, our study suggested that testosterone, estriol, pregnenolone and dehydroepiandrosterone might be differential metabolites for gestational diabetes mellitus. The genetic variants rs10046 of CYP19A1 and rs2257157 of HSD17B3 could predispose to GDM in Chinese women.

Steroid profile analysis by liquid chromatography-tandem mass spectrometry in second-trimester pregnant women for trisomy 21 screening

BACKGROUND

Trisomy 21 is a serious chromosome abnormality. The conventional Down's screening test is the most widely used for trisomy 21 screening. However, this method could lead to a higher false positive rate. Therefore, we aim to analyze steroid profile in second-trimester pregnant women and identify novel serum biomarkers of trisomy 21.

METHODS

We employed an LC-MS/MS method to measure the steroid profile. The concentrations and product-to-substrate ratios in 71 second-trimester pregnant women were determined and statistically analyzed to identify novel biomarkers for trisomy 21 screening.

RESULTS

We found that there were significant differences in levels of E3, 11-deoxycortisol, and 11-deoxycortisol /17-hydroxyprogesterone between two groups. The OPLS-DA plots revealed obvious separation between two groups. Combining VIP analysis (VIP > 1.0) with volcano plot (P < 0.05 and fold change >1.2 or < 0.83), 11-deoxycortisol was identified as a novel biomarker for trisomy 21. After controlling for confounders, we found 11-deoxycortisol was associated with trisomy 21 (adjusted P = 0.009), and the fully adjusted OR (95 % CI) was 0.098 (0.016-0.593) in highest quartile versus lowest quartile of 11-deoxycortisol (P = 0.011).

CONCLUSIONS

Steroid profile analysis for the first time showed that steroid hormones perturbations occurred in pregnant women carrying a fetus affected by trisomy 21 and decreased 11-deoxycortisol levels were associated with trisomy 21.

Plasma and serum oxylipin, endocannabinoid, bile acid, steroid, fatty acid and nonsteroidal anti-inflammatory drug quantification in a 96-well plate format

The goal of this research was to develop a high-throughput, cost-effective method for metabolic profiling of lipid mediators and hormones involved in the regulation of inflammation and energy metabolism, along with polyunsaturated fatty acids and common over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs). We describe a 96-well plate protein precipitation and filtration procedure for 50 μL of plasma or serum in the presence of 37 deuterated analogs and 2 instrument internal standards. Data is acquired in two back-to-back UPLC-MS/MS analyses using electrospray ionization with positive/negative switching and scheduled multiple reaction monitoring for the determination of 145 compounds, including oxylipins, endocannabinoids and like compounds, bile acids, glucocorticoids, sex steroids, polyunsaturated fatty acids, and 3 NSAIDs. Intra- and inter-batch variability was <25% for >70% of metabolites above the LOQ in both matrices, but higher inter-batch variability was observed for serum oxylipins and some bile acids. Results for NIST Standard Reference Material 1950, compared favorably with the 20 certified metabolite values covered by this assay, and we provide new data for oxylipins, N-acylethanolamides, glucocorticoids, and 17-hydroxy-progesterone in this material. Application to two independent cohorts of elderly men and women showed the routine detection of 86 metabolites, identified fasting state influences on essential fatty acid-derived oxylipins, N-acylethanolamides and conjugated bile acids, identified rare presence of high and low testosterone levels and the presence of NSAIDs in ∼10% of these populations. The described method appears valuable for investigations in large cohort studies to provide insight into metabolic cross-talk between the array of mediators assessed here.