Identification of 17-hydroxyprogesterone and other steroid hormones in saliva from a normal child and patients with congenital adrenal hyperplasia by plasmaspray liquid chromatography/mass spectrometry

[A promising approach for therapy control in congenital adrenal hyperplasia. Problems of Endocrinology]

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders requiring lifelong glucocorticoid replacement (GC) therapy. Lack of GC therapy leads to precocious puberty in boys, heterosexual development in girls, accelerated bone maturation and short final height in both sexes. In adolescence, the lack of GC therapy is the cause of menstrual disorders in girls and the development of TART in boys, as a result reducing the reproductive potential in both sexes. On the other hand, an overdose of GC leads to drug-induced Itsenko-Cushing's syndrome. In order to select adequate doses of GC in childhood and adolescence, multiple determinations of 17-hydroxyprogesterone, androstenedione, and testosterone in blood plasma, and thus multiple venous blood sampling are required. The blood sampling requires specially trained medical staff and can effect on the results due to stress reaction especially in young patients. Hence, the development and implementation of a non-invasive method for determining the steroid profile is extremely important in monitoring GC therapy in children. In addition, the currently used immunofluorescence assay cannot determine other adrenal steroids, has a high variation due to the «cross-reaction» of steroids that are similar in structure, which inflates the results. Unlike immunofluorescence assay, liquid chromatography and tandem mass spectrometry is more preferable method, since it is more specific and accurate. In this literature review, saliva presented as an alternative substrate and the non-invasive method for determining the steroid profile. This method can solve the above disadvantages, simplify and make more accurate the selection of GC therapy in patients with CAH, which is especially important in childhood.

LC–MS/MS in endocrinology: what is the profit of the last 5 years?

Currently, chromatography (GC but more commonly HPLC) is the analytical method of choice for several hormones, either because the immunoassays suffer from extensive crossreactivity or because chromatography permits simultaneous measurements of hormones. However, sometimes the conventional detection systems with HPLC methods do not meet desired specificity. With the increase of robust and affordable LC–MS/MS systems, the next step forward in specificity was taken. LC–MS/MS is rapidly being incorporated in the endocrine laboratories. To be useful in the clinical diagnostic practice, it is of utmost importance that methods are both analytically and clinically vaidated, as until now, the majority of applications of LC–MS/MS in the clinical laboratories are ‘home-made’ methods, therefore special case must be taken. This review aims to focus on Clinical and Laboratory Standards Institute or comparable validated LC–MS/MS methods for targeted hormone analysis used for diagnostic purposes in human samples, published in the last 5 years.

Development and performance evaluation of a tandem mass spectrometry assay for 4 adrenal steroids

BACKGROUND

Congenital adrenal hyperplasia is a group of autosomal recessive disorders caused by a deficiency of 1 of 4 enzymes required for the synthesis of glucocorticoids, mineralocorticoids, and sex hormones. Analysis of 11-deoxycortisol (11DC), 17-hydroxyprogesterone (17OHP), 17-hydroxypregnenolone (17OHPr), and pregnenolone (Pr) in blood allows detection of these enzyme defects.

METHODS

The steroids were extracted from 200 microL of serum or plasma by solid-phase extraction, derivatized to form oximes, and extracted again with methyl t-butyl ether. Instrumental analysis was performed on an API 4000 tandem mass spectrometer with electrospray ionization in positive mode and multiple reaction-monitoring acquisition.

RESULTS

The limits of detection were 0.025 microg/L for 11DC, 17OHP, and Pr and 0.10 microg/L for 17OHPr. The method was linear to 100 microg/L for 11DC, 17OHP, and Pr, respectively, and to 40 microg/L for 17OHPr. Within- and between-run (total) imprecision (CVs) were <7.1% and 11%, respectively. Reference intervals for children in Tanner stages 1 through 5 and adult males and females for 17OHP, 11DC, Pr, and 17OHPr were established. Prepared samples were stable for >72 h.

CONCLUSIONS

The detection limit and selectivity of this method and its small sample volume requirement allow analysis of endogenous concentrations of adrenal steroids in serum or plasma from children and adults. The method thus has an important potential role in the evaluation of the status of 4 of the enzymes involved in adrenal steroid biosynthesis.

Seasonal gonad progesterone pattern in the soft-shell clam Mya arenaria

Steroidogenesis, which plays a major role in the reproductive cycle of vertebrates, is still for the most part, unknown in invertebrates. The aim of this study was to examine the link between progesterone and the reproductive cycle in Mya arenaria. The soft-shell clams, Mya arenaria were collected in Anse à l'Orignal (Parc Provincial du Bic, Québec, Canada) from July to November 1998. Histological data have shown that female gonads of M. arenaria were in the spawning stage in August and September, while the male gonads were in the ripe stage. This period of active gametogenesis was associated with a depletion of lipid reserves. These lipids could be used as a source of energy and as a substrate for steroidogenesis. Liquid Chromatography coupled to Mass Spectroscopy (LC-MS) and quantified by Enzyme Linked ImmunoSorbent Assay (ELISA) determined progesterone. Progesterone levels in the gonad were increased during the ripe stage in the male and during the spawning stage in the female. These results indicate, for the first time, that progesterone, as in vertebrates, may play a role in the reproductive cycle of M. arenaria.

Proposed definitive methods for measurement of plasma testosterone and 17 alpha-hydroxyprogesterone

OBJECTIVES

This report provides the results of the development and evaluation of definitive isotope dilution/mass spectrometry (ID/MS) methods for the determination of testosterone and 17 alpha-hydroxyprogesterone in human plasma at concentrations ranging from 1.4 to 37.9 nmol/L and 1.5 to 45.4 nmol/L, respectively. The internal standards were 16, 16, 17-2H-testosterone and 21,21,21, -2H-17 alpha-hydroxyprogesterone. The development of optimum extraction and derivatization procedures, and studies of storage time, temperature effects, accuracy, and precision are presented.

RESULTS

The results indicate that the methods employing the TBDMS derivative of testosterone and MO-TMS derivative of 17 alpha-hydroxyprogesterone are capable of generating accurate and precise data at the inherently low concentrations given, with recovery greater than 95%. Accuracy of testosterone in the fortified steroid-free and pooled plasma by ID/MS measurement was good because the relative error ranged from +3.1% to -0.7, with a mean of 0.9% over the concentration levels of 1.4 to 37.9 nmol/L testosterone, and the imprecision ranged from 4.2% to 0.7% CV, with a mean of 1.9%. Accuracy of 17 alpha-hydroxyprogesterone in the fortified steroid-free and pooled plasma was also good, considering the inherently low concentrations. The relative error ranged from -2.1% to +1.5%, with a mean of 1.1%, and the imprecision ranged from 3.8% to 0.8% CV with a mean of 1.3% over concentration levels of 1.5 to 15.1 nmol/L. The high precision and accuracy and absence of statistically significant bias qualifies these methods as candidate definitive methods for plasma testosterone and 17 alpha-hydroxyprogesterone.

The metabolism of piperidine-type phenothiazine antipsychotic agents. II. Sulforidazine in dog and human

1. The metabolism of sulforidazine was studied in female dogs and adult male humans after oral administration of 37.5 mg and 25.0 mg, respectively. 2. Metabolites in organic extracts of dog urine were separated by h.p.l.c. and individually collected prior to mass spectrometric analysis, while organic extracts of human urine were directly subjected to plasmaspray h.p.l.c.-mass spectrometric determination. In the case of phenolic metabolites, the urinary extracts from both species were derivatized with a silylating reagent (with or without prior enzymic hydrolysis) and subsequently analysed by h.p.l.c.-mass spectrometry. The structures of metabolites with the exception of phenols were confirmed by comparison of their mass spectra and chromatographic behaviours with those of authentic standards. 3. The compounds identified in urine of both species were sulforidazine, two diastereomers of sulforidazine ring sulphoxide, the lactam of sulforidazine ring sulphoxide and a phenolic derivative of sulforidazine, whereas sulforidazine N-oxide and the lactam of sulforidazine were identified only in human urine. Moreover the phenolic metabolite was present in human urine in both unconjugated and conjugated forms, whereas dog urine had only the conjugated form. 4. Sulforidazine and some of its major metabolites were quantified by an h.p.l.c. method. The mean urinary excretions (0-48 h) of sulforidazine were similar in human (n = 3) and dog (n = 3) (5.9 +/- 0.7% and 7.2 +/- 1.9%), as were the excretions of sulforidazine ring sulphoxide (13.2 +/- 4.6% and 13.3 +/- 4.4%), while the lactam of sulforidazine ring sulphoxide was a major metabolite only in human (7.5 +/- 2.8% and < 0.1%). The lactam of sulforidazine was a minor metabolite in human. 5. The metabolites observed in human urine were similar to those previously reported in rat, except that sulforidazine N-oxide was found only in human, whereas the two diastereomers of N-desmethylsulforidazine ring sulphoxide were observed only in rat. These data suggest that rat may be a more suitable animal than dog for further study of the metabolism of the piperidine ring of sulforidazine.

Comparison of cortisol concentrations in saliva and plasma of dogs

It is increasingly important to have simple, non-invasive indicators of stress in animals. Studies in various species have shown that concentrations of cortisol in saliva relate closely to plasma levels of the free hormone; the aim of the present procedure was to show a similar correlation in the dog. Baseline blood and saliva samples were collected concurrently from six male beagles. Synthetic adrenocorticotrophic hormone was given and further samples were collected at 0.25, 0.5, one, two and 2.5 hours later. The results indicated a statistically significant correlation between the levels of cortisol in blood and saliva. Concentrations in saliva were between 5 and 10 per cent of those in plasma at each collection time. To demonstrate a response to a more natural stimulus, saliva samples were taken from a dog during exposure to a known stressor for that individual. The results showed a marked, delayed increase from baseline which was maintained for at least 0.5 hours after stressing.

Liquid chromatographic purification and detection of anabolic compounds

The role of liquid chromatography within methods of analysis for steroids, related compounds and beta-agonists in biological samples is discussed. Special attention is given to the application of liquid chromatography in sample preparation and extract clean-up. Different forms of liquid chromatography, including immunoaffinity chromatography, are compared and evaluated. Methods for confirmation based on gas chromatography-mass spectrometry and cryotrapping Fourier transform infrared spectrometry are discussed.