Use of novel picolinoyl derivatization for simultaneous quantification of six corticosteroids by liquid chromatography-electrospray ionization tandem mass spectrometry

Wide-Targeted Semi-Quantitative Analysis of Acidic Glycosphingolipids in Cell Lines and Urine to Develop Potential Screening Biomarkers for Renal Cell Carcinoma

Glycosphingolipids (GSLs), mainly located in the cell membrane, play various roles in cancer cell function. GSLs have potential as renal cell carcinoma (RCC) biomarkers; however, their analysis in body fluids is challenging because of the complexity of numerous glycans and ceramides. Therefore, we applied wide-targeted lipidomics using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with selected reaction monitoring (SRM) based on theoretical mass to perform a comprehensive measurement of GSLs and evaluate their potency as urinary biomarkers. In semi-quantitative lipidomics, 240 SRM transitions were set based on the reported/speculated structures. We verified the feasibility of measuring GSLs in cells and medium and found that disialosyl globopentaosylceramide (DSGb5 (d18:1/16:0)) increased GSL in the ACHN medium. LC-MS/MS analysis of urine samples from clear cell RCC (ccRCC) patients and healthy controls showed a significant increase in the peak intensity of urinary DSGb5 (d18:1/16:0) in the ccRCC group compared with that in the control group. Receiver operating characteristic analysis indicated that urinary DSGb5 could serve as a sensitive and specific marker for RCC screening, with an AUC of 0.89. This study demonstrated the possibility of urinary screening using DSGb5 (d18:1/16:0). In conclusion, urinary DSGb5 (d18:1/16:0) was a potential biomarker for cancer screening, which could contribute to the treatment of RCC patients.

Analysis of Metabolic Changes in Endogenous Metabolites and Diagnostic Biomarkers for Various Diseases Using Liquid Chromatography and Mass Spectrometry

Analysis of endogenous metabolites in various diseases is useful for searching diagnostic biomarkers and elucidating the molecular mechanisms of pathophysiology. The author and collaborators have developed some LC/tandem mass spectrometry (LC/MS/MS) methods for metabolites and applied them to disease-related samples. First, we identified urinary conjugated cholesterol metabolites and serum N-palmitoyl-O-phosphocholine serine as useful biomarkers for Niemann-Pick disease type C (NPC). For the purpose of intraoperative diagnosis of glioma patients, we developed the LC/MS/MS analysis methods for 2-hydroxyglutaric acid or cystine and found that they could be good differential biomarkers. For renal cell carcinoma, we searched for various biomarkers for early diagnosis, malignancy evaluation and recurrence prediction by global metabolome analysis and targeted LC/MS/MS analysis. In pathological analysis, we developed a simultaneous LC/MS/MS analysis method for 13 steroid hormones and applied it to NPC cells, we found 6 types of reductions in NPC model cells. For non-alcoholic steatohepatitis (NASH), model mice were prepared with special diet and plasma bile acids were measured, and as a result, hydrophilic bile acids were significantly increased. In addition, we developed an LC/MS/MS method for 17 sterols and analyzed liver cholesterol metabolites and found a decrease in phytosterols and cholesterol synthetic markers and an increase in non-enzymatic oxidative sterols in the pre-onset stage of NASH. We will continue to challenge themselves to add value to clinical practice based on cutting-edge analytical chemistry methodology.

Differentiation of human adipose tissue-derived mesenchymal stromal cells into steroidogenic cells by adenovirus-mediated overexpression of NR5A1 and implantation into adrenal insufficient mice

BACKGROUND AIMS

Cell therapy for adrenal insufficiency is a potential method for physiological glucocorticoid and mineralocorticoid replacement. We have previously shown that mouse mesenchymal stromal cells (MSCs) differentiated into steroidogenic cells by the viral vector-mediated overexpression of nuclear receptor subfamily 5 group A member 1 (NR5A1), an essential regulator of steroidogenesis, and their implantation extended the survival of bilateral adrenalectomized (bADX) mice.

METHODS

In this study, we examined the capability of NR5A1-induced steroidogenic cells prepared from human adipose tissue-derived MSCs (MSC [AT]) and the therapeutic effect of the implantation of human NR5A1-induced steroidogenic cells into immunodeficient bADX mice.

RESULTS

Human NR5A1-induced steroidogenic cells secreted adrenal and gonadal steroids and exhibited responsiveness to adrenocorticotropic hormone and angiotensin II in vitro. In vivo, the survival time of bADX mice implanted with NR5A1-induced steroidogenic cells was significantly prolonged compared with that of bADX mice implanted with control MSC (AT). Serum cortisol levels, which indicate hormone secretion from the graft, were detected in bADX mice implanted with steroidogenic cells.

CONCLUSIONS

This is the first report to demonstrate steroid replacement by the implantation of steroid-producing cells derived from human MSC (AT). These results indicate the potential of human MSC (AT) to be a source of steroid hormone-producing cells.

Derivatization, an Applicable Asset for Conventional HPLC Systems without MS Detection in Food and Miscellaneous Analysis

One of the most valuable practices for analyzing not-so-analytical-friendly analytes in complex, heterogenous matrices is derivatization. Availability of numerous derivatizing reagents (DRs) makes the modification of analyte more exploitable in terms of an analytical perspective. A wide array of derivatization techniques like pre or post-column, in-situ, enzymatic, ultrasound-assisted, microwave-assisted, photochemical derivatization has added much-needed methodological strength in analyzing intricate analytical matrices (food, water, and soil). In recent years, analytical chemistry has achieved greater heights through the development of new sensitive methods with simple conventional instruments like High-Performance Liquid Chromatography (HPLC) devoid of Mass detectors. The prompt availability of these straightforward instruments also makes it a favorable option for routine analysis in food, environmental, bioanalytical chemistry. Analyzing food, environmental or bioanalytical specimen has some of the most problematic aspects, like the low concentration of the analytes accompanied by not too suitable analytical properties. Even though conventional HPLC lacks the required sensitivity but merger with derivatization can lead to a remarkable increase in sensitivity. In recent years there has been a lot of application of diverse derivatizations to increase the sensitivity and selectivity of the analyte for available instruments, resulting in notable findings. Therefore, this review describes the application of derivatization principles in the analysis of analytes in food and additional matrices using conventional HPLC instruments such as HPLC-UV, HPLC-DAD, and HPLC-FD. In this article, we will briefly review the different modes and multiple types of derivatizing reagents with their mechanisms and importance for encouraging the use of established HPLC instruments.

Searching, Structural Determination, and Diagnostic Performance Evaluation of Biomarker Molecules for Niemann-Pick Disease Type C Using Liquid Chromatography/Tandem Mass Spectrometry

Niemann-Pick disease type C (NPC) is an autosomal recessive disorder that is characterized by progressive neuronal degeneration. Patients with NPC have a wide age of onset and various clinical symptoms. Therefore, the discovery and diagnosis of NPC are very difficult. Conventional laboratory tests are complicated and time consuming. In this context, biomarker searches have recently been performed. Our research group has previously also investigated NPC biomarkers based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) and related techniques. To identify biomarker candidates, nontargeted analysis with high-resolution MS and MS/MS scanning is commonly used. Structural speculation has been performed using LC/MS/MS fragmentation and chemical derivatization, while identification is performed by matching authentic standards and sample specimens. Diagnostic performance evaluation was performed using the validated LC/MS/MS method and analysis of samples from patients and control subjects. NPC biomarkers, which have been identified and evaluated in terms of performance, are various classes of lipid molecules. Oxysterols, cholenoic acids, and conjugates are cholesterol-derived molecules detected in the blood or urine. Plasma lyso-sphingolipids are biomarkers for both NPC and other lysosomal diseases. N-palmitoyl-O-phosphocholine-serine is a novel class of lipid biomarkers for NPC. This article reviews biomarkers for NPC and the analysis methods employed to that end.

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

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

Determination of Intraprostatic and Intratesticular Androgens

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

Biomarker analysis of Niemann-Pick disease type C using chromatography and mass spectrometry

Niemann-Pick disease type C (NPC) is an autosomal recessive disorder with progressive degradation of central nervous system. The age of the onset varies from perinatal to adulthood. Patients with NPC are affected in the central nervous system, peripheral nerves, and systemic organs. From these background, it is extremely difficult to discover NPC clinically and diagnose it correctly. The procedure of the conventional laboratory methods are complicated and it takes long time to obtain the result. Because of the importance of early treatments and the shortcomings of conventional diagnostic methods for NPC, remarkable attention has been paid to biomarkers and chemical diagnoses. In the last decade, many NPC biomarkers have been reported. They are classified as cholesterol-related metabolites, sphingolipid metabolites, and novel phospholipid metabolites, respectively. Therefore, these are all lipid metabolites. Various chemical analysis methods have been used for their identification. In addition, chromatography and mass spectrometry are mainly used for their quantification. This review article outlines NPC biomarkers reported in the last decade and their analytical methods.

HIGH STEROL ESTER 1 is a key factor in plant sterol homeostasis

Plants strictly regulate the levels of sterol in their cells, as high sterol levels are toxic. However, how plants achieve sterol homeostasis is not fully understood. We isolated an Arabidopsis thaliana mutant that abundantly accumulated sterol esters in structures of about 1 µm in diameter in leaf cells. We designated the mutant high sterol ester 1 (hise1) and called the structures sterol ester bodies. Here, we show that HISE1, the gene product that is altered in this mutant, functions as a key factor in plant sterol homeostasis on the endoplasmic reticulum (ER) and participates in a fail-safe regulatory system comprising two processes. First, HISE1 downregulates the protein levels of the β-hydroxy β-methylglutaryl-CoA reductases HMGR1 and HMGR2, which are rate-limiting enzymes in the sterol synthesis pathway, resulting in suppression of sterol overproduction. Second, if the first process is not successful, excess sterols are converted to sterol esters by phospholipid sterol acyltransferase1 (PSAT1) on ER microdomains and then segregated in SE bodies.

Carnosic Acid, Tangeretin, and Ginkgolide-B Anti-neoplastic Cytotoxicity in Dual Combination with Dexamethasone-[anti-EGFR] in Pulmonary Adenocarcinoma (A549)

Background:

Traditional chemotherapeutics of low-molecular weight diffuse passively across intact membrane structures of normal healthy cells found in tissues and organ systems in a non-specific unrestricted manner which largely accounts for the induction of most sequelae which restrict dosage, administration frequency, and duration of therapeutic intervention. Molecular strategies that offer enhanced levels of potency, greater efficacy and broader margins-of-safety include the discovery of alternative candidate therapeutics and development of methodologies capable of mediating properties of selective “targeted” delivery.

Materials and Methods:

The covalent immunopharmaceutical, dexamethasone-(C21-phosphoramidate)-[anti- EGFR] was synthesized utilizing organic chemistry reactions that comprised a multi-stage synthesis regimen. Multiple forms of analysis were implemented to vadliate the successful synthesis (UV spectrophotometric absorbance), purity and molar-incorporation-index (UV spectrophotometric absorbance, chemical-based protein determination), absence of fragmentation/polymerization (SDS-PAGE/chemiluminescent autoradiography), retained selective binding-avidity of IgG-immunoglobulin (cell-ELISA); and selectively “targeted” antineoplastic cytotoxicity (biochemistry-based cell vitality/viability assay).

Results:

The botanicals carnosic acid, ginkgolide-B and tangeretin, each individually exerted maximum antineoplastic cytotoxicity levels of 58.1%, 5.3%, and 41.1% respectively against pulmonary adenocarcinoma (A549) populations. Dexamethasone-(C21-phosphoramidate)-[anti-EGFR] formulated at corticosteroid/ glucocorticoid equivalent concentrations produced anti-neoplastic cytotoxicity at levels of 7.7% (10-9 M), 26.9% (10-8 M), 64.9% (10-7 M), 69.9% (10-6 M) and 73.0% (10-5 M). Ccarnosic acid, ginkgolide-B and tangeretin in simultaneous dual-combination with dexamethasone-(C21-phosphoramidate)-[anti-EGFR] exerted maximum anti-neoplastic cytotoxicity levels of 70.5%, 58.6%, and 69.7% respectively.

Discussion:

Carnosic acid, ginkgolide-B and tangeretin botanicals exerted anti-neoplastic cytotoxicity against pulmonary adenocarcinoma (A549) which additively contributed to the anti-neoplastic cytotoxic potency of the covalent immunopharmaceutical, dexamethasone-(C21-phosphoramidate)-[anti-EGFR]. Carnosic acid and tangeretin were most potent in this regard both individually and in dual-combination with dexamethasone-(C21- phosphoramidate)-[anti-EGFR]. Advantages and attributes of carnosic acid and tangeretin as potential monotherapeutics are a wider margin-of-safety of conventional chemotherapeutics which would readily complement the selective “targeted” delivery properties of dexamethasone-(C21-phosphoramidate)-[anti-EGFR] and possibly other covalent immunopharmaceuticals in addition to providing opportunities for the discovery of combination therapies that provide heightened levels of anti-neoplastic efficacy.

Effects of prenatal sex hormones on behavioral sexual dimorphism

BACKGROUND

We investigated the association between the hormone environment during the prenatal period using cord blood, and gender-role play behavior in school-aged children.

METHODS

A total of 879 school-aged children (433 boys and 446 girls) in a prospective birth cohort study in Hokkaido were enrolled to analyze the relationship between cord blood level of the sex hormones estradiol (E), testosterone (T), progesterone (P), and dehydroepiandrosterone (DHEA), and the Pre-School Activities Inventory (PSAI) score. The PSAI evaluated sex-typical characteristics, the type of preferred toys and play activities. The PSAI consists of 12 masculine and 12 feminine items, and the composite scores were calculated by subtracting the feminine score from the masculine score. Higher scores indicated male-typical behavior.

RESULTS

Composite and masculine PSAI scores were significantly higher in boys. Meanwhile, the feminine score was significantly lower in boys. Although T and P were significantly higher in boys, E/T was significantly higher in girls. In a multivariate regression model, including covariates of social factors, there was no correlation between any of the hormones and PSAI score in boys. In girls, only P and E/T were positively correlated with the feminine score.

CONCLUSIONS

Prenatal sex hormone exposure may influence the dimorphic brain development and behavior in school-aged girls. Furthermore, the cord blood hormone levels may not fully reflect the hormone environment during the prenatal period.

Sensitive and simultaneous quantitation of 6β-hydroxycortisol and cortisol in human plasma by LC-MS/MS coupled with stable isotope dilution method

CYP3A phenotyping provides a means for personalized drug therapy. We focused our attention on the plasma 6β-hydroxycortisol (6β-OHF) to cortisol ratio as an index for CYP3A phenotyping. In the present study, we developed a sensitive and reliable method for the simultaneous determination of 6β-OHF and cortisol in human plasma using high-performance liquid chromatography/tandem mass spectrometry together with picolinylester derivatization or nonderivatization methods and 6β-[9,11,12,12-² H₄ ]hydroxycortisol and [1,2,4,19-¹³ C₄ ]cortisol as internal standards for in vivo CYP3A phenotyping in humans. The lower limits of quantification were 38.513 pg/mL for 6β-OHF and 38.100 pg/mL for cortisol. The relative error and relative standard deviation of the lower limits of quantification were <5% for both methods. The intra-day and inter-day assay reproducibilities of the determined 6β-OHF and cortisol concentrations were consistent with the actual amounts added as relative errors and relative standard deviations for both methods, which were <5.4% and <3.9%, respectively. Both methods were applied for the quantification of plasma 6β-OHF and cortisol concentrations in healthy subjects taking oral contraceptives. The absolute concentrations and time course of 6β-OHF and cortisol were found to be consistent when measured using the 2 methods. The ratio as an index for in vivo CYP3A activity decreased after 21 days of taking oral contraceptives for both methods. To the best of our knowledge, this is the first study reporting the detailed investigation of accuracy and precision in the simultaneous measurement of 6β-OHF and cortisol in human plasma using liquid chromatography/tandem mass spectrometry coupled with stable isotope dilution method, which can be applied to CYP3A phenotyping.

Sex-related differences in the associations between maternal dioxin-like compounds and reproductive and steroid hormones in cord blood: The Hokkaido study

BACKGROUND

Prenatal exposure to dioxin-like compounds (DLCs) irreversibly affects fetal reproductive and steroid hormone synthesis.

OBJECTIVE

This study aimed to assess the relationships between maternal DLCs and cord blood reproductive and steroid hormones.

METHODS

Participants in this study were pregnant women who enrolled in the Sapporo Cohort of the Hokkaido Study between 2002 and 2005. We quantified 29 DLCs during the 2nd and 3rd trimesters in maternal blood. Additionally, we measured the concentrations of progesterone, estradiol (E2), testosterone (T), androstenedione, dehydroepiandrosterone (DHEA), cortisol, cortisone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, inhibin B, and insulin-like factor-3 (INSL3) in cord blood samples.

RESULTS

Data from 183 mother-child pairs were analyzed. We observed sex-dependent associations of DLCs on T/E2 ratios, DHEA, cortisol, cortisone, adrenal androgen/glucocorticoid (AA/GC: sum of DHEA and androstenedione)/(sum of cortisol and cortisone) ratios and SHBG. An increase in maternal DLCs related to decreased T/E2 ratios and SHBG and inhibin B levels, and increased AA/GC ratios and FSH and DHEA levels in male cord blood samples. However, an increase in maternal mono-ortho polychlorinated biphenyls related to increased cortisol, cortisone, and SHBG levels, and decreased DHEA levels and AA/GC ratios in female cord blood samples.

CONCLUSIONS

Prenatal exposure to DLCs alters steroidogenesis and suppresses the secretion of inhibin B in male cord blood. Relationships between maternal DLCs and cord blood hormones differ between boys and girls. Further studies are required to clarify whether the effects of in utero exposure to DLCs on adrenal hormones extend into infancy and puberty.

Relationship between adrenal steroid hormones in cord blood and birth weight: The Sapporo Cohort, Hokkaido Study on Environment and Children's Health

OBJECTIVES

We investigated the relationship between steroid hormone levels in cord blood and birth weight.

METHODS

Among 514 participants in a prospective birth cohort study in Sapporo, the following hormone levels were measured in 294 stored cord blood samples from 135 males and 159 females: androstenedione, dehydroepiandrosterone (DHEA), cortisol, and cortisone. Birth weight information was obtained from medical records.

RESULTS

Androstenedione/DHEA was significantly higher in males than in females, while DHEA was significantly higher in females. Birth weight was significantly higher in males than in females. Regarding cortisone, androstenedione/DHEA, and cortisone/cortisol, a correlation was observed with birth weight in males but not in females.

CONCLUSIONS

Prenatal adrenal steroids as well as converting enzymes such as 11ß-hydrosteroid dehydrogenase type 2 and 3ß-hydrosteroid dehydrogenase may have an impact on prenatal physical development.

Prenatal organochlorine pesticide exposure and the disruption of steroids and reproductive hormones in cord blood: The Hokkaido study

Certain organochlorine pesticides (OCPs) are designated as persistent organic pollutants and are regulated in many countries. The effects of OCPs on pediatric endocrinology are a concern; however, only limited data exist from human studies on maternal OCP exposure and its effects on infants' hormone levels. This study was conducted as part of the Hokkaido Study Sapporo Cohort, a prospective birth cohort study in Japan. Participants included 514 women who enrolled at 23-35weeks of gestation between 2002 and 2005; maternal blood samples were collected in late pregnancy, and 29 OCPs were measured. Reproductive and steroid hormone levels in cord blood were also determined. Characteristics of mothers and their infants were obtained from self-administered questionnaires and medical records. Ultimately, 232 samples with both OCP and hormone data were analyzed. Fifteen of 29 investigated OCPs were detected in over 80% of the samples, with p,p'-dichlorodiphenyldichloroethylene showing the highest concentration (median value: 619pg/g-wet). The association between OCPs and sex hormone levels varied by sex. Linear regression models after sex stratification showed that chlordanes, cis-hexachlorobenzene, heptachlor epoxide, Mirex, and toxaphenes in maternal blood were inversely associated with testosterone, cortisol, cortisone, sex hormone-binding globin, prolactin, and androstenedione-dehydroepiandrosterone (DHEA) and testosterone-androstenediones ratios among boys. Furthermore, these OCPs were positively correlated with DHEA, follicle stimulating hormone (FSH), and adrenal androgen-glucocorticoid and FSH-inhibin B ratios among boys. In categorical quartile models, testosterone and DHEA were inversely and positively associated with OCPs, respectively. Estradiol-testosterone and adrenal androgen-glucocorticoid ratios tended to increase with increasing OCP concentrations in the higher quartile, while the testosterone-androstenedione ratio tended to decrease. Sex hormone-binding globulin and prolactin showed an inverse association with OCPs. Among girls, the linear regression model showed that only p,p'-dichlorodiphenyltrichloroethane was inversely associated with the level of DHEA and the adrenal androgen-glucocorticoid ratio, but was positively associated with cortisone levels. However, no associations were observed using the quartile categorical model. These results suggest that prenatal exposure to OCPs disrupt reproductive hormones of fetuses in utero among boys, even at relatively low levels.

Simultaneous determination of paeonilactone A and paeonilactone B in rat plasma after oral administration of albiflorin by UPLC/TOF/MS following picolinoyl derivatization

A new highly sensitive analytical method was developed to investigate the in vivo metabolism of albiflorin, one of the most principal components in traditional Chinese medicine. After hydrolyzation with sulfatase, the main metabolites paeonilactone A and paeonilactone B of paeoniflorin in rat plasma were successfully detected for the first time by liquid chromatography mass spectrometry following picolinoyl derivatization. Borneol was used as the internal standard compound to quantify paeonilactone A and paeonilactone B in rat plasma. Paeonilactone A and paeonilactone B show different pharmacokinetic behaviors. The maximum plasma concentration of paeonilactone A reached 36.4±5.6ng/mL at about 8h after oral administration of albiflorin at a dose of 5mg/kg, while the maximum plasma concentration of paeonilactone B reached 12.4±3.4ng/mL at about 2h. The total metabolic pathway of albiflorin in rats was proposed. Albiflorin was found to be metabolized to the sulfate of paeonilactone A and paeonilactone B which may be responsible for the biological effect of albiflorin. The new analytical method may help to elucidate the clinical efficacy of traditional Chinese formula containing albiflorin.

Prenatal di(2-ethylhexyl) phthalate exposure and disruption of adrenal androgens and glucocorticoids levels in cord blood: The Hokkaido Study

Di(2-ethylhexyl) phthalate (DEHP) is known for its endocrine disrupting properties. We previously demonstrated that prenatal DEHP exposure is associated with decreased progesterone levels and testosterone/estradiol ratio in the cord blood. However, evidence of the effects of prenatal DEHP exposure on adrenal androgen and glucocorticoids in infants is scarce. Thus, the objectives of this study were to investigate the association between prenatal DEHP exposure and adrenal androgen and glucocorticoids, and to discuss its effects on steroid hormone profiles in infants. This is part of a birth cohort study: The Hokkaido Study on Environment and Children's Health, Sapporo Cohort. Among the 514 participants, 202 mother-infant pairs with available data on maternal mono(2-ethylhexyl) phthalate (MEHP), adrenal androgen (dehydroepiandrostenedione [DHEA] and androstenedione) and glucocorticoid (cortisol and cortisone) cord blood levels were included in this study. After adjusting for potential confounders, a linear regression analysis showed that maternal MEHP levels were associated with reduced cortisol and cortisone levels and glucocorticoid/adrenal androgen ratio, whereas increased DHEA levels and DHEA/androstenedione ratio. In a quartile model, when comparing the adjusted least square means in the 4th quartile of MEHP with those in the 1st quartile, cortisol and cortisone levels and glucocorticoid/adrenal androgen ratio decreased, whereas DHEA/androstenedione and cortisol/cortisone ratios increased. Significant p-value trends for cortisol and cortisone levels, cortisol/cortisone ratio, and glucocorticoid/adrenal androgen ratio were observed. In combination with the previous results of reduced progesterone levels and testosterone/estradiol ratio, prenatal exposure to DEHP altered the steroid hormone profiles of infants. Further studies investigating the long-term effects of DEHP exposure on growth, neurodevelopment, and gonad and reproductive function are required.

The Association of Prenatal Exposure to Perfluorinated Chemicals with Glucocorticoid and Androgenic Hormones in Cord Blood Samples: The Hokkaido Study

BACKGROUND

Perfluorinated chemicals (PFCs) disrupt cholesterol homeostasis. All steroid hormones are derived from cholesterol, and steroid hormones such as glucocorticoids and androgenic hormones mediate several vital physiologic functions. However, the in utero effects of PFCs exposure on the homeostasis of these steroid hormones are not well understood in humans.

OBJECTIVES

We examined the relationship between prenatal exposure to perfluorooctane sulfonate (PFOS)/perfluorooctanoate (PFOA) and cord blood levels of glucocorticoid and androgenic hormones.

METHODS

We conducted a hospital-based birth cohort study between July 2002 and October 2005 in Sapporo, Japan (n = 514). In total, 185 mother-infant pairs were included in the present study. Prenatal PFOS and PFOA levels in maternal serum samples were measured using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Cord blood levels of glucocorticoid (cortisol and cortisone) and androgenic hormones [dehydroepiandrosterone (DHEA) and androstenedione] were also measured in the same way.

RESULTS

We found a dose-response relationship of prenatal PFOS, but not PFOA, exposure with glucocorticoid levels after adjusting for potential confounders. Cortisol and cortisone concentrations were -23.98-ng/mL (95% CI: -0.47.12, -11.99; p for trend = 0.006) and -63.21-ng/mL (95% CI: -132.56, -26.72; p for trend < 0.001) lower, respectively, in infants with prenatal PFOS exposure in the fourth quartile compared with those in the first quartile. The highest quartile of prenatal PFOS exposure was positively associated with a 1.33-ng/mL higher DHEA level compared with the lowest quartile (95% CI: 0.17, 1.82; p for trend = 0.017), whereas PFOA showed a negative association with DHEA levels (quartile 4 vs. quartile 1: -1.23 ng/mL, 95% CI: -1.72, -0.25; p for trend = 0.004). We observed no significant association between PFCs and androstenedione levels.

CONCLUSIONS

Our results indicate that prenatal exposure to PFCs is significantly associated with glucocorticoid and DHEA levels in cord blood. Citation: Goudarzi H, Araki A, Itoh S, Sasaki S, Miyashita C, Mitsui T, Nakazawa H, Nonomura K, Kishi R. 2017. The association of prenatal exposure to perfluorinated chemicals with glucocorticoid and androgenic hormones in cord blood samples: the Hokkaido Study. Environ Health Perspect 125:111-118; http://dx.doi.org/10.1289/EHP142.

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

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

Effects of adrenal androgens during the prenatal period on the second to fourth digit ratio in school-aged children

OBJECTIVES

We investigated the relationship between the levels of adrenal steroid hormones in cord blood and the second to fourth digit ratio (2D/4D), which is regarded as an indirect method to investigate the putative effects of prenatal exposure to androgens, in school-aged children.

MATERIALS AND METHODS

Of the 514 mother-child pairs who participated in the prospective cohort study of birth in Sapporo between 2002 and 2005, the following adrenal steroid hormone levels in 294 stored cord blood samples (135 males and 159 females) were measured; cortisol, cortisone, androstenedione and dehydroepiandrosterone (DHEA). A total of 190 out of 350 children who were currently school-aged and contactable for this survey sent back photocopies of their palms for 2D/4D measurements.

RESULTS

2D/4D in all right hands, left hands, and mean values was significantly lower in males than in females (p<0.01). DHEA levels were significantly higher in females. A multivariate regression model showed that 2D/4D negatively correlated with DHEA in males only (p<0.01). No correlations were observed in the other adrenal steroid hormones tested in males or in any adrenal steroid hormones in females.

CONCLUSION

DHEA is mainly secreted in large amounts by the adrenal gland and is transformed into active sex-steroid hormones in peripheral tissues. The present study demonstrated that sex differences in digits were influenced by adrenal androgens during the prenatal period, possibly through intracrinological processes for androgen receptors located in fetal cartilaginous tissues.

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

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

Dexamethasone-(C21-phosphoramide)-[anti-EGFR]: molecular design, synthetic organic chemistry reactions, and antineoplastic cytotoxic potency against pulmonary adenocarcinoma (A549)

PURPOSE

Corticosteroids are effective in the management of a variety of disease states, such as several forms of neoplasia (leukemia and lymphoma), autoimmune conditions, and severe inflammatory responses. Molecular strategies that selectively "target" delivery of corticosteroids minimize or prevents large amounts of the pharmaceutical moiety from passively diffusing into normal healthy cell populations residing within tissues and organ systems.

MATERIALS AND METHODS

The covalent immunopharmaceutical, dexamethasone-(C21-phosphoramide)-[anti-EGFR] was synthesized by reacting dexamethasone-21-monophosphate with a carbodiimide reagent to form a dexamethasone phosphate carbodiimide ester that was subsequently reacted with imidazole to create an amine-reactive dexamethasone-(C21-phosphorylimidazolide) intermediate. Monoclonal anti-EGFR immunoglobulin was combined with the amine-reactive dexamethasone-(C21-phosphorylimidazolide) intermediate, resulting in the synthesis of the covalent immunopharmaceutical, dexamethasone-(C21-phosphoramide)-[anti-EGFR]. Following spectrophotometric analysis and validation of retained epidermal growth factor receptor type 1 (EGFR)-binding avidity by cell-ELISA, the selective anti-neoplasic cytotoxic potency of dexamethasone-(C21-phosphoramide)-[anti-EGFR] was established by MTT-based vitality stain methodology using adherent monolayer populations of human pulmonary adenocarcinoma (A549) known to overexpress the tropic membrane receptors EGFR and insulin-like growth factor receptor type 1.

RESULTS

The dexamethasone:IgG molar-incorporation-index for dexamethasone-(C21-phosphoramide)-[anti-EGFR] was 6.95:1 following exhaustive serial microfiltration. Cytotoxicity analysis: covalent bonding of dexamethasone to monoclonal anti-EGFR immunoglobulin did not significantly modify the ex vivo antineoplastic cytotoxicity of dexamethasone against pulmonary adenocarcinoma at and between the standardized dexamethasone equivalent concentrations of 10(-9) M and 10(-5) M. Rapid increases in antineoplastic cytotoxicity were observed at and between the dexamethasone equivalent concentrations of 10(-9) M and 10(-7) M where cancer cell death increased from 7.7% to a maximum of 64.9% (92.3%-35.1% residual survival), respectively, which closely paralleled values for "free" noncovalently bound dexamethasone.

DISCUSSION

Organic chemistry reaction regimens were optimized to develop a multiphase synthesis regimen for dexamethasone-(C21-phosphoramide)-[anti-EGFR]. Attributes of dexamethasone-(C21-phosphoramide)-[anti-EGFR] include a high dexamethasone molar incorporation-index, lack of extraneous chemical group introduction, retained EGFR-binding avidity ("targeted" delivery properties), and potential to enhance long-term pharmaceutical moiety effectiveness.

Beyond classical derivatization: analyte ‘derivatives’ in the bioanalysis of endogenous and exogenous compounds

The analysis of endogenous and exogenous analytes in biological matrices presents several challenges to the bioanalyst. These analytes are often present at low concentrations, typically in complex matrices, and may have physicochemical properties that are not amenable to LC–MS analysis. The bioanalyst thus relies heavily on the formation of analyte derivatives for the efficient quantification of these compounds. These derivatives are also critically employed to derive information on the biology of living systems, potential drug or disease targets, and biomarkers of drug efficacy, safety, or disease progression. In this perspective, we demonstrate how analyte derivatives are applied in modern bioanalytical workflows and we discuss the potential use of these derivatives in the future.

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

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

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

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

Improved profiling of estrogen metabolites by orbitrap LC/MS

Estrogen metabolites are important biomarkers to evaluate cancer risks and metabolic diseases. Due to their low physiological levels, a sensitive and accurate method is required, especially for the quantitation of unconjugated forms of endogenous steroids and their metabolites in humans. Here, we evaluated various derivatives of estrogens for improved analysis by orbitrap LC/MS in human serum samples. A new chemical derivatization reagent was applied modifying phenolic steroids to form 1-methylimidazole-2-sulfonyl adducts. The method significantly improves the sensitivity 2-100 fold by full scan MS and targeted selected ion monitoring MS over other derivatization methods including, dansyl, picolinoyl, and pyridine-3-sulfonyl products.

Effects of prenatal Leydig cell function on the ratio of the second to fourth digit lengths in school-aged children

Prenatal sex hormones can induce abnormalities in the reproductive system and adversely impact on genital development. We investigated whether sex hormones in cord blood influenced the ratio of the second to fourth digit lengths (2D/4D) in school-aged children. Of the 514 children who participated in a prospective cohort study on birth in Sapporo between 2002 and 2005, the following sex hormone levels were measured in 294 stored cord blood samples (135 boys and 159 girls); testosterone (T), estradiol (E), progesterone, LH, FSH, inhibin B, and insulin-like factor 3 (INSL3). A total of 350 children, who were of school age and could be contacted for this survey, were then requested via mail to send black-and-white photocopies of the palms of both the left and right hands. 2D/4D was calculated in 190 children (88 boys and 102 girls) using photocopies and derived from participants with the characteristics of older mothers, a higher annual household income, higher educational level, and fewer smokers among family members. 2D/4D was significantly lower in males than in females (p<0.01). In the 294 stored cord blood samples, T, T/E, LH, FSH, Inhibin B, and INSL3 levels were significantly higher in samples collected from males than those from females. A multivariate regression model revealed that 2D/4D negatively correlated with INSL3 in males and was significantly higher in males with <0.32 ng/mL of INSL3 (p<0.01). No correlations were observed between other hormones and 2D/4D. In conclusion, 2D/4D in school-aged children, which was significantly lower in males than in females, was affected by prenatal Leydig cell function.

Association between maternal exposure to di(2-ethylhexyl) phthalate and reproductive hormone levels in fetal blood: the Hokkaido study on environment and children's health

Prenatal di(2-ethylhexyl) phthalate (DEHP) exposure can produce reproductive toxicity in animal models. Only limited data exist from human studies on maternal DEHP exposure and its effects on infants. We aimed to examine the associations between DEHP exposure in utero and reproductive hormone levels in cord blood. Between 2002 and 2005, 514 pregnant women agreed to participate in the Hokkaido Study Sapporo Cohort. Maternal blood samples were taken from 23-35 weeks of gestation and the concentration of the primary metabolite of DEHP, mono(2-ethylhexyl) phthalate (MEHP), was measured. Concentrations of infant reproductive hormones including estradiol (E2), total testosterone (T), and progesterone (P4), inhibin B, insulin-like factor 3 (INSL3), steroid hormone binding globulin, follicle-stimulating hormone, and luteinizing hormone were measured from cord blood. Two hundred and two samples with both MEHP and hormones' data were included in statistical analysis. The participants completed a self-administered questionnaire regarding information on maternal characteristics. Gestational age, birth weight and infant sex were obtained from birth records. In an adjusted linear regression analysis fit to all study participants, maternal MEHP levels were found to be associated with reduced levels of T/E2, P4, and inhibin B. For the stratified analyses for sex, inverse associations between maternal MEHP levels T/E2, P4, inhibin B, and INSL3 were statistically significant for males only. In addition, the MEHP quartile model showed a significant p-value trend for P4, inhibin B, and INSL3 decrease in males. Since inhibin B and INSL3 are major secretory products of Sertoli and Leydig cell, respectively, the results of this study suggest that DEHP exposure in utero may have adverse effects on both Sertoli and Leydig cell development in males, which agrees with the results obtained from animal studies. Comprehensive studies investigating phthalates' exposure in humans, as well as their long-term effects on reproductive development are needed.

Two novel HSD3B2 missense mutations with diverse residual enzymatic activities for Δ5-steroids

CONTEXT

Classical 3β-hydroxysteroid dehydrogenase (3β-HSD) deficiency (3β-HSDD) is caused by loss-of-function mutations in the HSD3B2 gene encoding type II 3β-HSD, which has a key role in steroid biosynthesis, converting Δ5-steroids to Δ4-steroids in adrenal glands and gonads.

PATIENT

A patient (46, XX) was found to have elevated 17-hydroxyprogesterone (17-OHP) [203 nmol/l (normal range: 2·94 ± 0·9 nmol/l)] by newborn screening. Endocrinological examination revealed dramatically increased Δ5-steroids [e.g. 17-OH pregnenolone: 910 nmol/l (normal range: 12·6 ± 10·5 nmol/l)]. The patient had virilization of external genitalia with labial fusion, suggesting classical 3β-HSDD.

METHODS AND RESULTS

Consistent with the endocrinological data, the patient was a compound heterozygote for two novel missense mutations (p.Y190C and p.S218P) that were identified in HSD3B2. Both Y190 and S218 are conserved among mammals. The mutant proteins had severely impaired residual enzymatic activity in vitro, although both mutants retained higher activity for 17-OH pregnenolone than for the other Δ5-steroids. In a three-dimensional model of the enzyme based on the known structures of similar proteins, both mutations were located extremely close to the predicted substrate-binding pocket. This suggests that the mutations can cause a local conformational change in the substrate-binding pocket, leading to alterations of the binding affinities for Δ5-steroids.

CONCLUSIONS

We identified two novel missense mutations of HSD3B2 that resulted in unbalanced residual enzymatic activities for Δ5-steroids. As a potential novel mechanism, we propose that the mutations, which differently affect the activity towards different substrates, the effects of these mutations provide novel insights into the pathophysiology of 3β-HSDD.

New analytical method for the study of the metabolism of gentiopicroside in rats after oral administration by LC-TOF-MS following picolinoyl derivatization

The metabolism of gentiopicroside (GPS) in vivo was studied for the first time by LC-MS following picolinoyl derivatization. Incubation of erythrocentaurin, one of the main in vitro metabolites of GPS by intestinal bacteria, with liver microsome indicated that GPS might be metabolized to a final metabolite 3,4-dihydro-5-(hydroxymethyl)isochroman-1-one (HMIO) in vivo. After hydrolysis with sulfatase, HMIO was successfully detected in rat plasma after oral administration of GPS by LC-MS following picolinoyl derivatization. 4-Methoxyphenyl methanol was used as an internal standard to quantify HMIO in rat plasma. A metabolic pathway of GPS in rats is proposed. The monoterpene compound GPS was found to be metabolized to dihydroisocoumarin, which may be responsible for the pharmacological effect of GPS.

Utility of noninvasive biomatrices in pharmacokinetic studies

Blood and plasma are the biomatrices traditionally used for drug monitoring and their pharmacokinetic profiling. Blood is the circulating fluid in contact with all organs and tissues of body and thus is the most representative fluid for measuring systemic drug levels. However, venipuncture suffers from the caveat of being an invasive technique which often makes people reluctant to participate in clinical studies. Thus, there is a need for noninvasive bio-fluids that are ethically appropriate, cost-efficient and toxicologically relevant. These alternate bio-fluids may prove clinically useful as alternatives to plasma/serum in therapeutic drug monitoring, pharmacokinetic and toxicokinetic studies, doping control in sports medicine and to monitor local adverse effects. These may be of particular interest in the case of special population groups such as neonates, children, the elderly, terminally ill patients and pregnant or lactating women, and offer the advantage of circumvention of the demand for specialized personnel for sample collection. This review describes such noninvasive bio-fluids (saliva, sweat, tears and milk) that have been considered for pharmacokinetic drug analysis, emphasizing their sample preparation, its associated difficulties and their correlation with plasma.

Derivatization methods for quantitative bioanalysis by LC–MS/MS

LC with atmospheric pressure ionization MS is essential to a large number of quantitative bioanalyses for a variety of compounds, especially nonvolatile or highly polar compounds. However, in many instances, weak ionization, poor LC retention and instability of certain analytes hinder the development of the LC–MS/MS method. Chemical derivatization has been used for different classes of analytes to improve their ionization efficiency, chromatographic separation and chemical stability. This work presents an overview of chemical derivatization methods that have been applied to the quantitative LC–MS/MS analyses of nine classes of molecules, including aldehydes, amino acids, bisphosphonate drugs, carbohydrates, carboxylic acids, nucleosides and their associated analogs, steroids, thiol-containing compounds and vitamin D metabolites, in biological matrices.

Simultaneous quantification of steroids in rat intratesticular fluid by HPLC-isotope dilution tandem mass spectrometry

An isotope dilution mass spectrometry method has been developed for the simultaneous measurement of picolinoyl derivatives of testosterone (T), dihydrotestosterone (DHT), 17β-estradiol (E(2)), and 5α-androstan-3α,17β-diol (3α-diol) in rat intratesticular fluid. The method uses reversed-phase high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. Following derivatization of 10-μL samples of testicular fluid with picolinoyl chloride hydrochloride, the samples were purified by solid phase extraction before analysis. The accuracy of the method was satisfactory for the 4 analytes at 3 concentrations, and both inter- and intraday reproducibility were satisfactory for T, DHT, and E(2). Measurements of intratesticular T concentrations in a group of 8 untreated adult rats by this method correlated well with measurements of the same samples by radioimmunoassay. As in men, there was considerable rat-to-rat variability in T concentration, despite the fact that the rats were inbred. Although its levels were more than an order of magnitude lower than those of T, DHT was measured reliably in all 8 intratesticular fluid samples. DHT concentration also varied from rat to rat and was highly correlated with T levels. The levels of E(2) and 3α-diol also were measurable. The availability of a sensitive method by which to measure steroids accurately and rapidly in the small volumes of intratesticular fluid obtainable from individual rats will make it possible to examine the effects, over time, of such perturbations as hormone and drug administration and environmental toxicant exposures on the intratesticular hormonal environment of exposed individual males and thereby to begin to understand differences in response between individuals.

18-oxocortisol measurement in adrenal vein sampling as a biomarker for subclassifying primary aldosteronism

CONTEXT

18-Oxocortisol (18-oxoF) is a derivative of cortisol (F) that is produced by aldosterone synthase (CYP11B2). The potential for this steroid as a biomarker for differentiating patients with aldosterone-producing adenoma (APA) from those with idiopathic hyperaldosteronism (IHA) has not been examined.

OBJECTIVES

We measured 18-oxoF, aldosterone, and F in plasma from adrenal vein sampling (AVS) of patients with primary aldosteronism. We compared 18-oxoF levels and 18-oxoF/F ratios for their potential to differentiate APA from IHA.

DESIGN, SETTING, AND SUBJECTS

This study measured 18-oxoF, F, and aldosterone in AVS obtained from patients with unilateral APA (14 cases) or bilateral IHA (seven cases, 14 samples total) using liquid chromatography-tandem mass spectrometry and RIA analyses.

RESULTS

The levels of 18-oxoF and the ratios of 18-oxoF/F, before and after ACTH stimulation, were significantly higher in blood-draining APA than in those from the contralateral adrenal glands and from adrenal glands with IHA.

CONCLUSIONS

The 18-oxoF levels and ratios of 18-oxoF/F in AVS samples can be a clinically useful biomarker for differentiating APA from IHA and for determining the localization or lateralization of APA in patients with primary aldosteronism.

Highly sensitive and specific analysis of sterol profiles in biological samples by HPLC-ESI-MS/MS

High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) is a powerful method for the microanalysis of compounds in biological samples. Compared with gas chromatography-mass spectrometry (GC-MS), this method is more broadly applicable to various compounds and usually does not require a derivatization step before analysis. However, when neutral sterols are analyzed, the sensitivities of usual HPLC-MS/MS method are not superior to those of GC-MS because the sterols are relatively resistant to ionization. In this review, we introduce the recent development of HPLC-MS/MS analysis for the quantification of non-cholesterol sterols. By adding an effective derivatization step to the conventional procedure, sterol analysis by HPLC-MS/MS surpassed that obtained by GC-MS in sensitivity. In addition, sufficient specificity of this method was achieved by selected reaction monitoring (SRM) and thorough chromatographic separation of each sterol.

Selective stimulation by cinnamaldehyde of progesterone secretion in human adrenal cells

AIMS

Cinnamon bark has been used to treat menstrual pain and infertility. While several pharmacological studies have suggested anti-inflammatory properties, the mechanisms by which the herb exerts its various activities have not been well understood. Recent reports suggest menstrual distress is related to higher estradiol levels, higher estradiol/progesterone ratios. Cinnamaldehyde, a major active constituent of Cinnamomum cassia has been shown to stimulate cathecholamine release from adrenal glands. The objective of the present study is to examine whether cinnamaldehyde stimulates secretion of progesterone and other steroid hormones in human adrenal cells.

MAIN METHODS

Human adrenal cells, H295R were exposed for 24h in a serum-free medium to various concentrations of cinnamaldehyde. Steroid hormones in the cultured medium were measured by a highly sensitive LC-electrospray ionization-tandem mass spectrometry.

KEY FINDINGS

Exposure to cinnamaldehyde increased progesterone release in a dose-dependent manner. Testosterone and dehydroepiandrosterone concentrations decreased in the presence of cinnamaldehyde. The release of cortisol or estradiol was not affected by treatment with cinnamaldehyde. cAMP in the cultured medium was increased from 0.06+/-0.0007pmol/ml to 0.12+/-0.0028pmol/ml by exposure to cinnamaldehyde. The addition of isobutylmehtylxanthine, a phosphodiesterase inhibitor, caused a doubling of the amount of cAMP up to 0.397+/-0.036pmol/ml in the presence of cinnamaldehyde.

SIGNIFICANCE

These data suggest that cinnamaldehyde selectively induced progesterone production and inhibited production of testosterone and dehydroepiandrosterone in human adrenal cells.

Fusaric acid as a novel proton-affinitive derivatizing reagent for highly sensitive quantification of hydroxysteroids by LC-ESI-MS/MS

A highly sensitive derivatization method for liquid chromatography (LC)-electrospray ionization (ESI) tandem mass spectrometry of dehydroepiandrosterone (DHEA), testosterone (T), pregnenolone (P5), and 17alpha-OH-pregnenolone (17-OHP5) was developed based on the use of fusaric acid as a reagent. DHEA, P5, and 17-OHP5 were rapidly and quantitatively converted to the 3-fusarate esters by treatment with fusaric acid and 2-methyl-6-nitrobenzoic anhydride. The positive ESI-mass spectra of the fusarate esters of each steroid were dominated by the appearance of [M + H](+) as base peaks. The fusarate derivatization of these steroids showed 17.6-fold (DHEA), 11.9-fold (P5), 3.3-fold (17-OHP5), and 1.8-fold (T) higher sensitivity to those of the corresponding picolinate derivatives in LC-selected reaction monitoring.

Possible contribution of 2-aminoethoxydiphenyl-borate-sensitive Ca2+ mobilization to adrenocorticotropin-induced glucocorticoid synthesis in rat adrenocortical cells

Cytoplasmic calcium ([Ca(2+)](i)) provided through voltage-dependent Ca(2+) channels (VDCC) plays an important role in adrenocorticotropin (ACTH)-induced steroidogenesis in adrenocortical cells. To identify alternative mechanisms for [Ca(2+)](i) supply, we investigated the 2-aminoethoxydiphenyl borate (2APB)-sensitive pathway as one of the possible signaling pathways involved in [Ca(2+)](i) supply for ACTH-induced steroidogenesis. In monolayers of cultured rat adrenal fasciculate and reticularis cells, ACTH at 10(-11) M stimulated corticosterone synthesis without increasing intracellular cAMP, and corticosterone synthesis was decreased by 10 microM 2APB by 51.8% (6.71 +/- 0.97 vs. 3.23 +/- 0.05 ng/mL/4 hours; p<0.05). Furthermore, 2APB significantly decreased the 10(-11) M ACTH-stimulated [Ca(2+)](i). ACTH increased the intracellular inositol-1,4,5-trisphosphate (IP3) content with a peak at 10(-13) M ACTH, which illustrates the possibility that ACTH activates IP3/diacylglycerol- dependent protein kinase C signal transduction. However, the difference in ACTH concentrations between that responsible for the IP3 increase and steroidogenesis without elevated cAMP, suggest a hypothesis that IP3 is not required for steroidogenesis, but does involve an unknown messenger, which stimulates the release of Ca(2+) from the ER or the subsequent store-operated Ca(2+) entry (SOCE). The pregnenolone concentration in the culture medium was increased by ACTH, which was significantly suppressed by 2APB, showing that the 2APB-sensitive Ca(2+) supply affects cholesterol transport into the mitochondrial membrane via steroidogenic acute regulatory protein. Therefore, the SOCE may contribute to ACTH-induced steroidogenesis in the mitochondrial region. In conclusion, the [Ca(2+)](i) used for steroidogenesis may be derived from a 2APB-sensitive pathway and via VDCCs, particularly at physiological concentrations of ACTH. We suggest that ACTH receptors activate steroidogenesis via inositol triphosphate, or an unknown downstream messenger, which could be inhibited by 2APB.

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

We developed highly sensitive detection of testosterone (T) and 5alpha-dihydrotestosterone (DHT) by liquid chromatography-electrospray ionization tandem mass spectrometry using high proton affinitive derivatization of 17beta-hydroxyl group of T and DHT with picolinic acid, mobile phase consisting of MeCN-MeOH-H(2)O-formic acid and conventional octadecylsilica (ODS) column. Purification of the derivatives was carried out using solid-phase extraction with ODS cartridge. By this method, T and DHT were determined simultaneously with limits of quantification (LOQs) of 1 pg/0.2 ml in serum, and T and DHT with LOQs of 0.5 pg and 1 pg/3mg in prostate tissue, respectively, under acceptable assay performance (intra-assay and inter-assay accuracy and precision). The present method provides reliable and reproducible results for quantification of T and DHT in small volumes of serum and prostate samples for diagnosis in prostatic disorders and male climacteric.