Gas Chromatography-Mass Spectrometry Analysis of Urinary Steroid Metabolomics for Detection of Early Signs of Adrenal Neoplasm Malignancy in Patients with Cushing's Syndrome.

The metabolomics of urinary steroids was studied by gas chromatography-mass spectrometry in 25 patients with Cushing's syndrome without malignant potential and in 12 patients with malignant potential of adrenal neoplasms (Weiss score 1-3). Patients with adrenocortical adenoma (N=24) constituted the control group. In patients with Cushing's syndrome and malignant potential, increased urinary excretion of 16-oxo-androstendiol, tetrahydro-11-deoxycortisol, and 16-hydroxypregnendiol, which had 100% specificity and sensitivity >90% for the diagnosis of malignant potential. Additionally, non-classical 5-ene-pregnenes (16-OHpregnenolone, 21-OH-pregnenolone, 3ß,16,20-pregnentriol, and 3ß,17,20-pregnentriol) were identified. The revealed changes in the metabolomics of steroids can be early signs of malignant potential in patients with Cushing's syndrome. In patients with malignant potential, three signs of reduced activity of 11ß-hydroxysteroid dehydrogenase type 2 were detected and in patients without malignant potential, one sign was found. In patients with and without malignant potential, three signs increased activity of 5ß-reductase were found.

Different Types of Urinary Steroid Profiling Obtained by High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectrometry in Patients with Adrenocortical Carcinoma.

Urinary steroid profiling (USP) was studied using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) methods in 108 patients with adrenocortical adenoma (ACA) and in 31 patients with adrenocortical carcinoma (ACC). Thirteen ACC and Cushing's syndrome (ACC-CS) patients had two types of USP as well as 18 ACC patients without hypercortisolism. These four types differed by androgen and glucocorticoid secretion of the adrenal cortex. Fifteen main ACC features were observed by GC-MS. Urinary excretion of dehydroepiandrosterone (DHEA) was increased in 67.7 % of ACC patients and tetrahydro-11-deoxycortisol (THS) in 74.2 %. By combination of the following parameters: THS >900 µg/24 h and/or DHEA >1500 µg/24 h with ratios of 3α,16,20-pregnentriol/3ß,16,20-pregnentriol (3α,16,20dP3/3ß,16,20dP3) less than 6.0 and 3α,17,20dP3/3ß,17,20dP3 less than 9.0 and the detection of "non-classical" 5-en-pregnens, not found in ACA and healthy persons, 100 % sensitivity and specificity of ACC and ACA differential diagnosis were achieved. Features of 21-hydroxylase and 11ß-hydroxylase deficiency were observed by GC-MS in 32.2 and 61.3 % of the ACC patients, respectively. Additional features for ACC-CS diagnostic were increased urinary excretion of 6ß-hydroxycortisol, 18-hydroxycorticosterone, the sum (UFF + UFE) obtained by HPLC, tetrahydrocorticosterone, and the sum (THF + THE + allo-THF) obtained by GC-MS.

The use of hormonal agents in the treatment of acne.

Hormones and androgens play an important role in the pathogenesis of acne. Multiple hormonal modulators are now available for the treatment of acne. The efficacies and side effects of currently available hormonal agents are reviewed here including the use of oral contraceptives, spironolactone, flutamide, cyproterone acetate, finasteride, and cortexolone 17α-propionate. Hormonal therapies are an efficacious treatment option for acne among females. With the growing need to reduce antibiotic exposures, hormonal therapies should be more widely studied and incorporated into acne treatment strategies.

Involvement of epidermal growth factor receptors and mitogen-activated protein kinase in progestin-induction of sperm hypermotility in Atlantic croaker through membrane progestin receptor-alpha.

The intracellular pathways mediating rapid, nongenomic progestin stimulation of sperm motility remain unclear. The role of epidermal growth factor receptors (Egfr and ErbB2) and mitogen-activated protein kinase (Mapk) in membrane progestin receptor-alpha (mPRα)-mediated progestin stimulation of sperm hypermotility was examined in a teleost, Atlantic croaker. Inhibition of upstream regulators of Egfr, intracellular tyrosine kinase (Src) with PP2, and matrix metalloproteinase (MMP) with Ilomastat, abolished progestin-initiated sperm hypermotility by 17,20ß,21-trihydroxy-4-pregnen-3-one (20ß-S; 20 nM) and a specific mPRα agonist, Org OD 02-0 (20 nM). Pretreatment of croaker sperm with EGFR inhibitors, AG1478 (5 µM) and RG13022 (50 µM), the ErbB2 inhibitor, AG879 (5 nM), or the MEK1/2 inhibitor, U0126 (500 nM) blocked progestin stimulation of sperm motility. Levels of phosphorylated extracellular-related kinase 1 and 2 (P-Erk1/2) were increased after 20ß-S treatment. These results demonstrate that progestin-mediated hypermotility via mPRα in croaker sperm involves activation of the Egfr, ErbB2 and Mapk pathways.

Diagnostic Value of Urinary Steroid Profiling in the Evaluation of Adrenal Tumors.

Radiological examination may unexpectedly reveal an adrenal mass. Current algorithms for differentiating between benign and malignant lesions mainly rely on size and densitometry on unenhanced CT, which have limited specificity. We examined the diagnostic value of urinary steroid profiling by gas chromatography/mass-spectrometry (GC/MS) in differentiating between benign and malignant adrenal tumors. A retrospective study in two referral centers for patients with adrenal disease was performed. All urinary steroid profiles ordered for evaluation of an adrenal tumor between January 2000 and November 2011 were examined. Patients were diagnosed with adrenal cortical carcinoma (ACC), adrenal cortical adenoma (ACA), or other adrenal mass. Results of hormonal measurements, imaging studies, pathology reports, and clinical outcome were retrieved from medical records. The diagnostic value of individual urinary steroid metabolites was determined by receiver operating characteristics analysis. Cut-off values were compared to reference values from an age and gender-standardized population of healthy controls. Eighteen steroid metabolites were excreted in significantly higher concentrations in patients with ACC (n = 27) compared to patients with ACA (n = 107) or other adrenal conditions (n = 18). Tetrahydro-11-deoxycortisol (THS) at a cut-off value of 2.35 µmol/24 h differentiated ACC from other adrenal disorders with 100% sensitivity and 99% specificity. Elevated urinary excretion of THS was associated with a very high sensitivity and specificity to differentiate between an ACC and a benign adrenal mass. Urinary steroid profiling might be a useful diagnostic test for the evaluation of patients with an adrenal incidentaloma.

Membrane progestin receptor alpha mediates progestin-induced sperm hypermotility and increased fertilization success in southern flounder (Paralichthys lethostigma).

Progestin hormones stimulate sperm motility in teleosts but their mechanisms of action remain unclear. Preliminary results suggest that progestin upregulation of sperm motility in southern flounder and several other marine species is mediated through a sperm membrane progestin receptor with the characteristics of membrane progestin receptor alpha (mPRα, also known as Paqr7b). The hypothesis that mPRα has an important role in progestin regulation of southern flounder sperm motility and fertility was tested in the present study. The specific mPRα agonist, 10-ethenyl-19-norprogesterone (Org OD 02-0, 100nM), mimicked the stimulatory actions of the endogenous progestin, 17,20ß, 21-trihydroxy-4-pregnen-3-one (20ß-S, 100nM) on flounder sperm motility. The concentration of the mPRα protein on sperm plasma membranes was positively correlated to sperm motility as well as the responsiveness of sperm to progestin stimulation. Acute in vitro progestin treatment of sperm with high mPRα protein levels increased both sperm motility and fertilization success in strip spawning experiments. However, in vitro progestin treatments were ineffective on sperm with low receptor abundance. A single injection of the superactive gonadotropin-releasing hormone analog (LHRHa, 100µg/kg) increased sperm motility and fertilization success in strip spawning experiments 72h post-injection which was accompanied by an increase in mPRα protein concentrations on sperm plasma membranes. These results provide clear evidence that southern flounder sperm hypermotility is mediated through mPRα. Stimulatory G proteins, but not inhibitory G proteins, were identified in flounder sperm plasma membrane fractions. The finding that treatment of flounder sperm plasma membrane fractions with either 20ß-S or Org OD 02-0 increases cAMP levels suggests progestins stimulate flounder sperm motility by activating an mPRα/stimulatory G protein/membrane adenylyl cyclase pathway. A similar mechanism has been identified in Atlantic croaker, suggesting that the signaling pathway mediated by mPRα in sperm is highly conserved in advanced teleosts. Collectively, our results indicate that progestin-stimulation of flounder sperm hypermotility and fertility is dependent on a sufficient concentration of mPRα which can be upregulated by in vivo LHRHa treatments. These findings potentially have practical applications for enhancing the fertility of male flounder broodstock.

Progestin signaling through mPRα in Atlantic croaker granulosa/theca cell cocultures and its involvement in progestin inhibition of apoptosis.

Although there is substantial evidence that membrane progestin receptors (mPRs) perform a critical physiological role in meiotic maturation of fish oocytes, it is unknown whether they are also intermediaries in progestin signaling in the surrounding follicular cells. Here, we show that mPRα protein is located on the plasma membranes of both granulosa and theca cells (G/T cells) isolated from Atlantic croaker ovaries and is associated with the presence of a single high affinity, limited capacity, pertussis toxin-sensitive, specific progestin [17,20ß,21-trihydroxy-4-pregnen-3-one (20ß-S)] membrane binding site with the characteristics of mPRα. Treatment of G/T cells with 20ß-S caused rapid G protein activation and a transient, pertussis toxin-sensitive, decrease in cAMP levels, whereas the selective nuclear progesterone receptor agonist, R5020, did not cause G protein activation, consistent with previous reports on mPRα signaling. 20ß-S treatment decreased serum starvation-induced cell death in both G/T cells and in seatrout mPRα-transfected MDA-MB-231 cells, whereas R5020 was ineffective. Moreover, a selective mPRα agonist, 10-ethenyl-19-norprogesterone, mimicked the protective action of 20ß-S against cell death, which was lost upon knockdown of mPRα protein but not after progesterone receptor knockdown, further demonstrating an involvement of mPRα. Signaling molecules involved in inhibition of apoptosis, Erk and serine-threonine kinase, were activated in G/T cells by 20ß-S, which suggests a potential mechanism for mPRα inhibition of apoptosis. This is the first study to demonstrate endogenous mPR signaling in the ovarian follicle and to suggest a novel physiological role for mPRα in mediating the antiapoptotic actions of progestins in ovarian follicle cells.

In the ventral tegmental area, progestins' membrane-mediated actions for lordosis of hamsters and rats involve protein kinase A.

Progestin-facilitated lordosis of hamsters and rats is enhanced by activation of dopamine type 1 (D1) or GABAA/benzodiazepine receptor complexes (GBRs) in the ventral tegmental area (VTA) and these effects involve G-proteins and second messengers, such as adenosine 3',5'-monophosphate (cAMP). We examined whether D1- and/or GBR-mediated increases in progestin-facilitated lordosis of female hamsters and rats involve the cAMP-dependent protein kinase, protein kinase A (PKA), in the VTA. In experiment 1, ovariectomized hamsters, primed with estradiol (E2; 10 microg at h 0) + progesterone (P; 100 microg at h 45), were first pre-tested for lordosis and motor behavior (h 48) and then infused with the PKA inhibitor, Rp-cAMP (100 ng/side), or vehicle. Thirty minutes later, hamsters were retested and then received infusions of the D1 agonist, SKF38393 (100 ng/side), the GBR agonist, muscimol (100 ng/side), or vehicle to the VTA. Hamsters were post-tested for lordosis and motor behavior 30 min later. In Experiment 2, ovariectomized rats, primed with E2 (10 microg at h 0), were first pre-tested for lordosis and then infused with Rp-cAMP (100 ng/side) or vehicle to the VTA at h 44. Immediately after testing, rats received infusions of SKF38393 (100 ng/side), muscimol (100 ng/side), or vehicle and were retested for lordosis. Rats were then infused with the neurosteroid, 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP; 100 or 200 ng/side), or beta-cyclodextrin vehicle and were post-tested for lordosis and motor behavior 10 and 60 min later. The enhancing effects of progestins or progestins plus D1 or GBR activation on lordosis of E2-primed hamsters and rats were blocked by the PKA inhibitor, Rp-cAMP. Thus, in the VTA, progestins' membrane actions involving D1 or GBRs are mediated, in part, by PKA.

Pharmacological profile of 9,11-dehydrocortexolone 17alpha-butyrate (CB-03-04), a new androgen antagonist with antigonadotropic activity.

A series of new cortexolone-related derivatives has been synthesized and investigated for potential anti-androgenic activity. Among the steroids evaluated, 9,11-dehydrocortexolone 17alpha-butyrate (CB-03-04) was the most promising one. The compound displayed a strong local antiandrogenic activity in hamster's flank organ test, and it was also found to be effective in the rat after subcutaneous injection. When compared to other well known androgen antagonists, the rank order of topical anti-androgenic activity in that test was: cyproterone acetate (CAS 427-51-0) > or = CB-03-04 > finasteride (CAS 98319-26-7) > flutamide (CAS 13311-84-7). In addition, the steroid had selective antigonadotropic activity, when injected into parabiotic rats, and was about as active as progesterone. The activity of CB-03-04 was ascribed mainly to its ability to compete with the stimulating effects of testosterone and dihydrotestosterone and, concurrently, to inhibit the gonadotropins hypersecretion. This bimodal mechanism of action could be predictive for the clinical usefulness of the steroid in the treatment of prostate cancer and benign prostate hypertrophy.

Steroid-induced oocyte maturation in Atlantic croaker (Micropogonias undulatus) is dependent on activation of the phosphatidylinositol 3-kinase/Akt signal transduction pathway.

Exposure of fully grown fish and amphibian oocytes to a maturation-inducing steroid (MIS) activates numerous signal transduction pathways to initiate the final stage of oocyte maturation. These events culminate in the activation of maturation-promoting factor and germinal vesicle breakdown (GVBD). In most species, exposure to MIS causes a transient decrease in oocyte cAMP levels. Whether this reduction in oocyte cAMP concentration is sufficient to induce GVBD is unclear. The current study tested the hypothesis that activation of cAMP-independent signal transduction pathways by the naturally occurring MIS, 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S), is necessary for GVBD in Atlantic croaker (Micropogonias undulatus) oocytes. Results indicate that although 20beta-S treatment of oocyte membranes significantly reduced cAMP production, incubation of follicles with the cell-permeable cAMP-dependent protein kinase (Prka) inhibitors Rp-cAMP or KT5720 did not promote GVBD in the absence of 20beta-S. Additionally, treatment of follicles with the phosphodiesterase (Pde) inhibitors Cilostamide (Pde3) or Rolipram (Pde4) significantly reduced GVBD, but they were not able to completely block it. In contrast, pharmacologic inhibition of the cAMP-independent phosphatidylinositol 3-kinase (Pik3)/Akt signal transduction pathway using the Pik3 inhibitors Wortmannin or LY294002, or the Akt inhibitor ML-9, blocked 20beta-S-induced GVBD. Finally, mitogen-activated protein kinase (Mapk1/3) activity increased after treatment with 20beta-S; however, inhibition of Mapk1/3 activity using PD98059 or U0126 had no effect on GVBD. These results demonstrate that activation of cAMP-independent signaling pathways, especially the Pik3/Akt pathway, is necessary for 20beta-S-induced GVBD in Atlantic croaker oocytes.

Identification of 17,20beta,21-trihydroxy-4-pregnen-3-one as an oocyte maturation-inducing steroid in black porgy, Acanthopagrus schlegeli.

The identity of the maturation-inducing steroid (MIS) in black porgy, Acanthopagrus schlegeli, a marine protandrous teleost, is unknown. Previous studies demonstrated that two teleost MISs, the progestins 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S) and 17,20beta-dihydroxy-4-pregnen-3-one (DHP) can induce maturation of black porgy oocytes in vitro. The purpose of the present study was to identify the major progestin produced during oocyte maturation (OM) in black porgy and investigate whether its secretion increases during this process. Females were injected twice with a LHRH analog to induce OM. Ovarian follicles undergoing OM were incubated in vitro with tritiated [3H]pregnenolone precursor and the tritiated products were extracted, purified, and identified by HPLC, TLC, acetylation, and recrystallization. Significant amounts of tritiated products were biosynthesized from [3H]pregnenolone that co-migrated with 20beta-S but not with DHP on HPLC and TLC. Similar TLC profiles were obtained with the tritiated products isolated from the HPLC/TLC 20beta-S fraction and standard 20beta-S after the acetylation reaction. The identity of the tritiated products as 20beta-S was confirmed by recrystallization. 20beta-S had a slightly higher potency than DHP in the inducing in vitro final oocyte maturation. Plasma 20beta-S concentrations increased significantly during the oocyte maturation after injection with a LHRH analog. The present data suggest that 20beta-S is the MIS in black porgy.

Endogenous urinary steroids in premenopausal women with uterine leiomyomas.

OBJECTIVES: To study the effect of endogenous steroids on the presence of uterine leiomyomas. METHODS: Urine samples of 27 premenopausal women with leiomyomas and 25 age-matched healthy premenopausal women were collected. The concentration of estrogens and androgens in the urine samples of the two groups were determined using a gas chromatography mass spectrometer and the two groups were compared. To study metabolic changes in patients indirectly, the concentration ratios of precursor metabolite to product metabolite of the two groups were also compared. RESULTS: Urinary concentrations of 17beta-estradiol, 5-androstene-3beta, 16beta, 17beta, triol, 11-keto-ethiocholanolone, 11beta-hydroxy-androsterone, 11beta-hydroxy-etiocholanolone, THS, THA, THE, alpha-cortol and beta-cortol were significantly higher in patients than in controls. The concentration ratios of 17beta-estradiol/estrone and 11/beta-hydroxy-ethiocholanolone/11beta-hydroxy-androsterone increased in patients. CONCLUSIONS: The presence of uterine leiomyomas correlates with an increase in urinary concentrations of estrogens and androgens, and it appears to be caused by a decrease in patients' metabolism of steroids.

Biological profile of cortexolone 17alpha-propionate (CB-03-01), a new topical and peripherally selective androgen antagonist.

The aim of this study was to investigate the antiandrogenic activity of a new monoester of cortexolone, cortexolone 17alpha-propionate (CAS 19608-29-8, CB-03-01). Although the compound displayed a strong local antiandrogenic activity in hamster's flank organ test, it did not exhibit antiandrogenic activity in rats after subcutaneous injection, nor did it affect gonadotropins hypersecretion when injected to parabiotic rats. As topical antiandrogen, the steroid resulted about 4 times more active than progesterone (CAS 57-83-0) and, when compared to known antiandrogen standards, it was about 3 times more potent than flutamide (CAS 13311-84-7), about 2 times more effective than finasteride (CAS 98319-26-7) and approximately as active as cyproterone acetate (CAS 427-51-0). Its pharmacological activity seemed to be primarily related to its ability to antagonistically compete at androgen receptor level; nevertheless its primary pharmacological target needs to be further investigated. Its topical activity, along with the apparent absence of systemic effects, anticipates this compound to have the potential of representing a novel and safe therapeutic approach for androgen-dependent skin disorders.

Effects of the maturation-inducing steroid on LH secretion and the GnRH system at different stages of the gonadal cycle in Atlantic croaker.

The effects of treatment with the maturation-inducing steroid 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S) on luteinizing hormone-releasing hormone analog (LHRHa)-induced LH secretion were examined during several phases of the gonadal cycle in Atlantic croaker, Micropogonias undulatus. 20beta-S (1 and 5 microg/g of body wt) was administered by intraperitoneal (ip) injection, 24 h prior to injection with LHRHa (10-50 ng/g of body wt) and fish were bled 1 h after LHRHa injection. Treatment with both doses of 20beta-S resulted in plasma concentrations of the steroid within the normal physiological range for this species during final oocyte maturation and ovulation. The 20beta-S treatments altered the LH response to LHRHa throughout the reproductive cycle in both sexes, but the direction and magnitude of the response varied. 20beta-S treatment decreased the LH response to LHRHa in fish with recrudescing and fully recrudesced gonads and in females with regressed gonads. On the other hand, 20beta-S treatment significantly increased the LH response to LHRHa in males with regressing or regressed gonads. 20beta-S treatment also altered preoptic anterior hypothalamic (POAH) and pituitary seabream gonadotropin-releasing hormone (sbGnRH) contents, and the patterns of these changes were similar to those observed in LH secretion. The finding that moderate increases in plasma 20beta-S concentrations, similar to those occurring during final oocyte maturation, significantly inhibit the LH response to LHRHa at the end of the reproductive cycle suggests that this action of 20beta-S is of physiological importance during the periovulatory period. Moreover, the fact that concurrent changes occur in POAH and pituitary sbGnRH contents suggests that the actions of 20beta-S on LH secretion are at least partly mediated via the GnRH system.

Plasma steroids in mature common dentex (Dentex dentex) stimulated with a gonadotropin-releasing hormone agonist.

The aim of this study was to identify the major C21 steroids produced in vivo during artificially induced final oocyte maturation and spawning in female common dentex (Dentex dentex). During the spawning season, mature females were treated with a gonadotropin-releasing hormone agonist (GnRHa)-loaded delivery system, with or without pimozide (given as a single dose at the beginning of the experiment). Blood samples were collected at various intervals during the experiment and were assayed for GnRHa, 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P), and 17,20beta,21-trihydroxy-4-pregnen-3-one (17,20beta,21-P). A higher percentage of ovulated females was observed in GnRHa-implanted fish, which produced over 10 times more eggs than controls. Relative fecundity was highest in the GnRHa + pimozide group and lowest in controls. The viability of naturally released eggs was low (2 to 15%) in all groups. Plasma concentrations of 17,20beta-P in GnRHa-implanted fish did not increase, but those in control fish decreased, such that there was a significant difference between control and treated fish between 2 and 10 days after treatment. In another experiment, ovulating common dentex were injected intramuscularly with a single dose of 50 microg kg(-1) of GnRHa in saline and were sampled for blood at 0, 3, 6, 12, and 24 h postinjection. A single water sample was taken from the tanks at 9 h postinjection, the tanks having been emptied and refilled at 6 h. Measurements were made of plasma and water concentrations of free and conjugated 17,20beta-P, 17,20beta,21-P, 17beta-oestradiol (E2), and GnRHa (plasma only). The GnRHa injection increased plasma levels of all steroids, with free 17,20beta-P reaching maximal levels within 3 h. GnRHa treatment also increased the amounts of free and conjugated steroids released into the water between 6 and 9 h.

Steroid profiles in cultured female jundiá, the Siluridae Rhamdia quelen (Quoy and Gaimard, Pisces Teleostei), during the first reproductive cycle.

The jundiá Rhamdia quelen (Quoy and Gaimard) is a teleost species from the Siluridae family and is an important species for aquaculture in temperate and subtropical climates. Gonad and blood tissue samples were taken from cultured jundiá females between 1998 and 1999. Plasma concentrations of 17beta-estradiol (E(2)), testosterone (T), 11-ketotestosterone (11-KT), 17-hydroxy-4-pregnene-3,20-dione (17-P), 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P), and 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S) were measured by radioimmunoassay and potential correlations with the stage of oogenesis and sexual maturation examined. During the experimental period two spawning episodes were observed. Plasma concentrations of E(2) increased progressively during oocyte development, simultaneously with the appearance of yolk vesicles and increasing amounts of deposited yolk. In female jundiá, the T peak occurred in October and was coincident with the peak in gonadosomatic index. Two distinct peaks of progestogens were detected, corresponding to the two spawning episodes, suggesting that one or more of these steroids might act as the "maturational-inducing steroid" in jundiá. Unusually large amounts of 11-KT were also measured in the plasma of mature jundiá females. The identity of 11-KT was confirmed by thin-layer chromatography. Although the profiles of the other steroids are compatible with the roles proposed for the action of these hormones in other teleosts, the role of 11-KT, normally found only in males, is unknown.

Sex steroids relative to alternative mating behaviors in the simultaneous hermaphrodite Serranus subligarius (Perciformes: Serranidae).

This study is the first investigation of reproductive endocrinology in a simultaneously hermaphroditic teleost, the belted sandfish (Serranus subligarius). We address two questions: (1) Do steroid hormone levels vary during the spawning season or during the daily spawning cycle of sandfish? (2) Do hormone levels vary relative to an individual's phenotype-size, frequency of spawning and aggressive behaviors, and proportion of testis in the gonad? We analyzed circulating estradiol-17beta (E2), testosterone (T), 11-ketotestosterone (11KT), 17alpha,20beta,21-trihydroxy-4-pregnen-3-one (20betaS), and 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP) concentrations in a field population. Only E2 levels were significantly higher at the new and full moon, suggesting peak periods of vitellogenesis at these times. Naturally spawning sandfish were sampled every 2 h during the photophase of a 25-h period (12 pm to 1 pm the following day) and gonadosomatic index, degree of oocyte hydration and ovulation, and plasma levels of E2, T, DHP, and 20betaS were analyzed. E2 and T levels did not vary during photophase, suggesting continuous recruitment of oocytes into vitellogenesis. The 20betaS levels peaked around the time of final oocyte maturation. Since frequency of spawning behaviors changes with body size, we captured individuals of various sizes throughout the spawning season and analyzed circulating levels of hormones. 11KT and 20betaS levels increased significantly with body size. In 1992, we quantified frequency of spawning and aggressive behaviors, circulating T and 11KT levels and testicular mass relative to ovotestis mass in focal animals. 11KT levels tended to be positively correlated with frequency of courting male behavior, but were unrelated to the frequency of aggressive behavior or testis mass. Because hormone levels increased with size and frequency of each spawning behavior changes with size, we propose that sex steroids influence growth-related changes in spawning tactics of individuals.

Correlation between plasma steroid hormones and vitellogenin profiles and lunar periodicity in the female golden rabbitfish, Siganus guttatus (Bloch).

Characteristics of the lunar reproductive cycle in the golden rabbitfish, Siganus guttatus, were determined by histological observations of ovarian development, and immunological measurements of plasma steroid hormones, estradiol-17beta (E2), testosterone (T), 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP) and 17alpha,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S), and vitellogenin (VTG). Ovarian and plasma samples were collected every week according to the lunar phases from May to July. Weekly change of gonadosomatic index (GSI) showed two peaks at the first lunar quarter in June and July. Yolky oocytes were also observed around this time. Histological observations revealed that the vitellogenic oocytes appeared again 1 week after spawning and developed synchronously. These results suggest that this species is a multiple spawner and the oocyte development is in a group-synchronous manner. Plasma steroid hormones (E2, T, DHP and 20beta-S) and VTG levels changed in parallel with changes in GSI. The peak of plasma VTG level occurred prior to spawning. These cyclic changes of plasma steroid hormones and VTG support the hypothesis that lunar periodicity is the major factor in stimulating reproductive activity of S. guttatus.

Cortisol metabolism in the postoperative period after cardiac surgery.

Relative 11beta-hydroxysteroid dehydrogenase deficiency has been shown previously to arise from endogenous hypercortisolism in diseases of the hypothalamic/pituitary/adrenocortical system; whether stress induced hypercortisolism may also result in substrate overload of 11beta-hydroxysteroid dehydrogenase has not yet been studied. We therefore studied the characteristics of cortisol metabolisation during the postoperative period of cardiac surgery, representing a well standardized surgical procedure. In a prospective, observational, consecutive case study, 14 patients undergoing cardiac surgery were investigated. During the first two days after cardiac surgery urine was collected from the patients during two 10 hour overnight periods (8 p.m. (day of surgery) until 6 a.m., and during the following night). Using capillary gas-chromatography, main urinary cortisol metabolites were quantified (tetrahydrocortisone, tetrahydrocortisol, allo-tetrahydrocortisol, cortolones, cortols as sum of cortisol metabolites (CM)). Free urinary cortisol (FUC) was determined by an automated immunoassay after extraction. The ratio of cortisol metabolites (tetrahydrocortisol, allo-tetrahydrocortisol, cortols) to cortisone metabolites (tetrahydrocortisone, cortolones) was calculated to characterize the overall activity of 11beta-hydroxysteroid dehydrogenase, an enzyme system catalyzing the conversion of cortisol to inactive cortisone (CMR, cortisol metabolisation ratio). Total cortisol metabolisation (including hepatic ring A-reduction and conjugation) was estimated by a cortisol turnover quotient (CM/FUC). In all urinary samples the ratio of cortisol to cortisone metabolites was markedly elevated compared to controls (patients: median 1.9, interquartile range 1.5-2.4, absolute range 1.0-3.2; controls: median 0.45, interquartile range 0.36-0.52); this ratio was positively correlated to FUC (r2 = 0.30; p = 0.003). The cortisol turnover quotient was markedly reduced (patients: median 38.0, interquartile range 20.0-103.9, absolute range 8.3-211.9; controls: median 259, interquartile range 176-415) and inversely correlated to FUC (r2 = 0.64, p < 0.001). It is concluded that major surgical trauma results in a marked relative reduction of cortisol inactivation probably consequent to substrate overload of the metabolizing enzymes; as the activity of these enzymes (mainly 11beta-hydroxysteroid dehydrogenase) is crucial for the modulation of cortisol receptor access, tissue corticoid sensitivity in the postoperative period may vary substantially from physiological conditions.

Pesticides interfere with the nongenomic action of a progestogen on meiotic maturation by binding to its plasma membrane receptor on fish oocytes.

Although many environmental contaminants disrupt endocrine function by binding to nuclear steroid receptors, it is not known whether they are capable of binding to steroid membrane receptors and interfering with nongenomic actions of steroids. The binding of several organochlorine pesticides to the plasma membrane receptor for the maturation-inducing steroid, 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S), in the ovaries of spotted seatrout (Cynoscion nebulosus) was investigated in in vitro competition assays. Kepone and o,p'-DDD were competitive inhibitors of 20beta-S binding and caused concentration-dependent displacement of [3H]-20beta-S from its receptor site over the range of 10(-4) to 10(-6) or 10(-7) M, whereas several other pesticides had lower affinities for the receptor. Interference with the nongenomic actions of 20beta-S on final meiotic maturation of spotted seatrout oocytes (final oocyte maturation, FOM) was examined in an in vitro bioassay. A concentration-dependent inhibition of FOM in response to 20beta-S was observed after 5 min and 12 h exposure to the same range of Kepone and o,p'-DDD concentrations (10(-4) to 10(-6) or 10(-7) M). The close correspondence between competitive binding of the two pesticides to the 20beta-S membrane receptor and their inhibition of 20beta-S induced FOM suggests a mechanism of endocrine disruption mediated by binding to a steroid membrane receptor and antagonism of a nongenomic steroid action.