Steroid Fraction Research Articles

Intracranial meningiomas: factors that influence the development of cerebral edema after stereotactic radiosurgery and radiation therapy.

To evaluate causative factors of cerebral edema after stereotactic radiosurgery or stereotactic radiation therapy in intracranial meningiomas. Of 43 adult patients with intracranial meningiomas, three received 13.5-18-Gy single-fraction stereotactic radiosurgery; one received 19.8 Gy in three fractions, one received 42 Gy in six fractions, and 31 received 32-36 Gy in six to eight fractions of stereotactic radiation therapy; and seven received 45-54-Gy external-beam radiation with 20-28 Gy in five to seven fractions as concomitant stereotactic boosts. Brain edema was estimated by calculating the edema index. After irradiation, all 11 patients with parasagittal and four patients with nonparasagittal tumors developed worsening cerebral edema that necessitated the administration of steroids (P < .001). The statistically significant factors for the development of edema were parasagittal location, presence of pretreatment edema, sagittal sinus occlusion, and the use of more than 6 Gy per fraction. Five patients with parasagittal tumors developed life-threatening panhemispheric edema, which was fatal in one. The causative factors of panhemispheric edema were a large tumor, single-fraction stereotactic radiosurgery, or use of more than 6 Gy per fraction. A smaller dose per fraction and aggressive use of steroids may help prevent life-threatening complications due to worsening edema.

Isolation and purification method of 6-oxoestradiol using Girard's reagent P.

An efficient synthetic method of 6-oxoestradiol was established by modifying the previous method by Garza and Rao. The present method is characterized by the quantitative extraction of 6-oxoestradiol produced during an oxidation reaction using Girard's reagent P (GP). The procedure is as follows: (1) reaction of estradiol-3, 17-diacetate with 5-dimethylpyrazole/chromium trioxide complex in dichloromethane; (2) column chromatography (SiO2) of the reaction mixture to obtain steroidal fraction by dichloromethane as an eluent, followed by saponification of the eluate; (3) reaction of the product with GP in methanol; (4) removal of the nonketonic steroid from an aq. layer, where the hydrazone of 6-oxoestradiol is remained; (5) formation of 6-oxoestradiol by acidification of the aq. layer. The overall yield of the 6-oxoestradiol from estradiol was greater than 45 percent.

Cataractogenesis after total body irradiation

Purpose : To evaluate the prognostic factors and the ophthalmologic follow-up on cataract formation following total body irradiation (TBI) prior to bone marrow transplantation (BMT). Methods and Materials : Between 1980 and 1992, 494 patients were referred to our department for TBI prior to BMT. The mean age was 32 ± 11 (median: 32, range: 2–63) years and the male to female ratio was 1.6 (304:190). The majority of patients were treated for acute leukemia (lymphoblastic, n = 177, 36%; or nonlymphoblastic, n = 139, 28%); 80 (16%) for chronic myeloid leukemia, 60 (12%) for non-Hodgkin's lymphoma, 23 (5%) for multiple myeloma, and 15 (3%) for other malignancies. Two hundred and fifty-four (51%) patients were grafted in the first complete remission (CR), 118 (24%) in second CR. Allogeneic BMT was performed in 210 (43%) patients, and autologous BMT in 284 (57%). Methotrexate combined to steroids ( n = 47, 22%) or to cyclosporine ( n = 163, 78%) was administered for graft-versus-host disease (GvHD) prophylaxis. In 188 patients (38%), heparin was used in the prevention of veno-occlusive disease (VOD) of the liver. Furthermore, steroid administration was registered in 223 patients (45%). The conditioning chemotherapy consisted of cyclophosphamide (Cy) alone in 332 (67%) patients. Total-body irradiation was administered either in single dose (STBI; 10 Gy in 1 day, n = 291) or in six fractions (FTBI; 12 Gy over 3 consecutive days, n = 203) before BMT. The mean instantaneous dose rate was 0.0574 ± 0.0289 Gy/min (0.024–0.1783). It was < 0.048 Gy/min in 157 patients (LOW group), ≥ 0.048 Gy/min and < 0.09 Gy/min in 301 patients (MEDIUM group), and ≥ 0.09 Gy/min in 36 patients (HIGH group). Results : When considering all patients, 42 (8.5%) patients developed cataracts after 13 to 72 months (median: 42 months) with a 5-year estimated cataract incidence (ECI) of 23%. Thirty-three (11.3%) out of 291 patients in the STBI group, and 9 (4.4%) out of 203 patients in the FTBI group developed cataracts with 5-year estimated incidences of 34 and 11%, respectively ( p = 0.0004). Seven (19.4%) out of 36 patients in the HIGH group, 33 (10.9%) out of 301 in the MEDIUM group, and 2 (1.2%) out of 157 in the LOW group developed cataracts with respective 5-year cataract incidences of 54%, 30%, and 3.5% (HIGH vs. MEDIUM, p = 0.07; MEDIUM vs. LOW, p = 0.0001; HIGH vs. LOW, p < 0.0001). On the other hand, patients who received heparin as prophylactic treatment against VOD of the liver had less cataracts than those who did not receive (5-year ECI of 16% vs. 28%, respectively; p = 0.01). There was no statistically significant difference in terms of 5-year ECI according to age, sex, administration of steroids, GvHD prophylaxis, type of BMT, or previous cranial radiotherapy in children. Multivariate analysis revealed that the instantaneous dose rate ( p = 0.001), and the administration of heparin against VOD ( p = 0.05) were the two independent factors influencing the cataract incidence, while age, fractionation, and use of steroids were not. Among the 42 patients who developed cataracts, 38 had bilateral extracapsular cataract extraction and intraocular lens implantation, and only 4 (10%) developed secondary cataracts in a median follow-up period of 39 months. Conclusion : Among the abovementioned TBI parameters, high instantaneous dose rate seems to be the main risk factor of cataract formation, and the administration of heparin appears to have a protective role in cataractogenesis. On the other hand, ionizing radiation seems to have a protective effect on posterior capsule opacification following extracapsular cataract extraction and intraocular lens implantation.

Molecular interactions between lipids and some steroids in a monolayer and a bilayer. 2

Molecular interactions between L-α-dipalmitoylphosphatidylcholine (DPPC) and some steroids having different hydrophilic groups in a monolayer and in a bilayer are investigated in terms of surface pressure, permeability, and microviscosity. The steroids used in this study are stigmasterol, 4,22-stigmastadien-3-one (stadiene), and stigmasterol acetate (acetate). The collapse pressures for the mixed monolayer of DPPC with various steroids depend upon the molar ratio (X) and types of hydrophilic groups in steroids. A one-stage collapse is observed for X ≤ 0.5 of stigmasterol, X ≤ 0.3 of stadiene and acetate, whereas a two-stage collapse is seen in other molar ratios of the steroids. The mole fraction within which liposomes are formed is dependent upon the types of hydrophilic group within the steroids. In comparing monolayer and bilayer membranes (liposomes), liposomes are formed at the mole fraction of steroids which have a one-stage collapse in DPPC/steroid mixed monolayer. The permeability ofthe bilayer membrane decreases with increasing cohesive force between DPPC and steroids, but increases with a decrease in microviscosity near the hydrophilic portions, in the following order : stigmasterol < stadiene < acetate. This study demonstrates that the permeability of liposomes is dependent upon the hydrophilic group of the steroids, and the stability of the liposomes increases with an increase in the cohesive forces between DPPC and the steroids.

Studies on steroids in fetuses and neonates: identification of 16-dehydropregnenolone in the circulation of pre-term neonates.

Unconjugated steroids were extracted with dichloromethane from the serum of pre-term neonates. Conjugated steroid fraction in the residue was separated and purified by high performance liquid chromatography. The purified steroid fraction was subjected to enzyme (arylsulfatase from Helix pomatia) or acid hydrolysis. Liberated steroid was analyzed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography-Fourier transformation infrared spectroscopy (GC/FT-IR). All of the results obtained from GC/MS and GC/FT-IR analysis were identical with those of authentic 16-dehydropregnenolone (3 beta-hydroxy-5,16-pregnadien-20-one, 16-DHP). This is the first report to demonstrate the presence of 16-DHP in human blood.

Clinical study on 26 cases of incidental adrenal tumors: a consideration on surgical indication

At our medical center we have seen 151 patients who have undergone adrenalectomy from 1971 up until June 1992. There has been a recent increase in the number of cases since 99 patients have been seen in the last eight years from 1985. This increase is related to the increase in the number of incidental tumors. Of those 99, 26 have been incidental tumors. Twenty-four of those have been endocrine inactive tumors, and the remaining 2, both active endocrinologically, were pheochromocytoma. We propose that our tentative indications for surgical treatment of incidental tumors are 1) tumors of diameter 3.5 cm or greater, 2) tumors undeniably malignant by imaging diagnosis, 3) tumors that tend to increase in size with every six-month re-examination, even though the original size is less than 3.5 cm in diameter, and 4) tumors endocrinologically active. The main purpose of this study was to make a differential diagnosis of malignant tumors among incidental tumors. Diagnostic modalities included 1) imaging diagnosis such as echography, CT, MRI, and angiography, 2) analysis of DNA ploidy and BrdU uptake utilizing flow cytometry of excised adrenal tumor tissues, and 3) analysis of urinary steroid fraction. It is generally thought that there are currently no methods by which malignant tumors can be differentiated with certainty, even with modern diagnostic technology, and review of the literature, finds approval or disapproval with regard to the methods we selected to evaluate tumors. What has aroused interest in our results is urinary 17KS fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma dehydroepiandrosterone sulfate serves as a prehormone for 48% of follicular fluid testosterone during treatment with menotropins.

Evidence has suggested that dehydroepiandrosterone sulfate (DS) is a prehormone for ovarian steroidogenesis. To study this hypothesis, combined 6-h infusions of [3H]dehydroepiandrosterone sulfate and [14C]testosterone ([14C]T) were performed in four normal women treated with menotropins who were undergoing medically indicated surgery, and the data were compared to those from nine normal women. The concentrations of tracer and nonisotopic DS, androst-5-ene-3 beta,17 beta-diol sulfate (delta 5diolS), androst-5-ene-3 beta,17 beta-diol (delta 5diol), dehydroepiandrosterone (D), androstenedione (delta 4A), and T were determined in arterial and venous blood and in follicular fluid. From these data, the concentrations and fractions of steroids in the follicular fluid that were derived from DS were calculated from the specific activity of intravascular DS and the concentrations of follicular fluid tracer steroids and their specific activities. The fractions of T (0.48), delta 5diol (0.31), delta 5diolS (0.42), and D (0.25) in follicular fluid arising from circulating DS were similar and were not significantly different from that of follicular DS arising from circulating DS (0.32). However, the fraction of follicular fluid delta 4A (0.041) was significantly less (P < 0.01), and the fractions of intrafollicular estrone and estradiol arising from DS were both less than 0.04. The mean MCR of DS in the women treated with menotropins of 22.0 +/- 3.5 L/day (mean +/- SE) was significantly higher than the normal control value. These findings elucidate an important mechanism of adrenal/ovarian interaction at the level of steroidogenesis; circulating DS serves as a prehormone for the production of intrafollicular delta 5diolS, delta 5 diol, D, and T.

Efficacy of the steroidal fraction of fenugreek seed extract on fertility of male albino rats

AbstractT. foenum‐graecum seed extract (100 mg/day/rat) was fed orally to male albino rats for 60 days. The sperm count and motility of cauda spermatozoa declined significantly leading to negative fertility tests. The organ weights as well as androgen dependent parameters (protein, sialic acid and fructose) were lower, revealing the reduction in circulating androgen. Cholesterol is a precursor of androgen. The increase in testicular and serum cholesterol may be co‐related with its nonutilization by the system, leading to a fall in circulating androgen and hence the altered histoarchitecture observed. Therefore T. foenum‐graecum extract exerts both antifertility and antiandrogenic activities.

Treatment of endometrial adenomatosis with tamoxifen

1. Treatment with tamoxifen of persistent endometrial hyperplasia with adenomatous phenomena resistant to traditional hormone therapy caused disappearance of adenomatosis in 90.5% cases after 3 months. 2. The character of the menstrual cycle during therapy may serve as a clinical prognostic criterion of its effectiveness. 3. The antiproliferative effect of tamoxifen may be manifest not only at the target cell level but also by increasing the synthesis of SSBG and reducing the free fractions of sex steroids.

Metabolism of progesterone and testosterone in human parotid and submandibular salivary glands in vitro

Twenty-three parotid and twelve submandibular human salivary glands were used for analyzing in vitro metabolism of progesterone (P) and/or testosterone (T), in order to find out their possible contribution to the concentrations of salivary P or T. Glands were excised from 21 women and 14 men because of a stone, tumor or sialoadenitis, and the healthy tissue was used for incubation. The tissues were homogenized and incubated with 5 to 7 nmol/l of [ 14C]P or [ 14C]T for 2 h, extracted with methylacetate and subjected to two dimensional thin-layer chromatography. The thin-layer plates were autoradiographed, and the radioactivity of the different metabolites were counted to assess the amounts of metabolites formed. No lipoidal or conjugated steroids were formed. All of the radioactivity was associated with the free fraction of steroids. Both P and T were metabolized significantly more actively in male submandibular gland compared to male parotid gland ( P < 0.05–0.01). No significant differences were found between female and male parotid glands, nor between the parotid glands of hormonally medicated (oral contraceptives or postmenopausal estrogen treatment) and non-medicated women. The submandibular glands more actively metabolized the steroids studied than the parotids ( P < 0.01). The main metabolites were 20α-hydroxy-4 pregnen-3-one for P, and androstenedione for T. In conclusion, the present results bring further evidence that the P or T levels in saliva may not be identical with the unbound steroid fraction in circulation, but a part of the steroids are metabolized in salivary glands. However, due to the rapid passage of steroids from blood to saliva, the metabolism demonstrated probably does not form an important source of error in salivary P and T measurements.

Studies on anabolic steroids—12. Epimerization and degradation of anabolic 17β-sulfate-17α-methyl steroids in human: Qualitative and quantitative GC/MS analysis

The epimerization and dehydration reactions of the 17β-hydroxy group of anabolic 17β-hydroxy-17α-methyl steroids have been investigated using the pyridinium salts of 17β-sulfate derivatives of methandienone 1, methyltestosterone 4, oxandrolone 7, mestanolone 10 and stanozolol 11 as model compounds. Rearrangement of the sulfate conjugates in buffered urine (pH 5.2) afforded the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes in a ratio of 0.8:1. These data indicated that both epimerization and dehydration of the 17β-sulfate derivatives were not dependent upon the respective chemical features of the steroids studied, but were instead inherent to the chemistry of the tertiary 17β-hydroxy group of these steroids. Interestingly, in vivo studies carried out with human male volunteers showed that only methandienone 1, methyltestosterone 4 and oxandrolone 7 yielded the corresponding 17-epimers 2, 5 and 8 and the 18-nor-17,17-dimethyl-13(14)-enes 3, 6 and 9 in ratios of 0.5:1, 2:1 and 2.7:1, respectively. No trace of the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of mestanolone 10 and stanozolol 11 was detected in urine samples collected after administration of these steroids. These data suggested that the in vivo formation of the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of 17β-hydroxy-17α-methyl steroids is also dependent upon phase I and phase II metabolic reactions other than sulfation of the tertiary 17β-hydroxyl group, which are probably modulated by the respective chemical features of the steroidal substrates. The data reported in this study demonstrate that the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes are not artifacts resulting from the acidic or microbial degradation of the parent steroids in the gut as previously suggested by other authors, but arise from the rearrangement of their 17β-sulfate derivatives. Unchanged oxandrolone 7 was solely detected in the unconjugates steroid fraction whereas unchanged steroids 1, 4 and 11 were recovered from the glucuronide fraction. These data are indirect evidences suggesting that the glucuronide conjugates of compounds 1 and 4 are probably enol glucuronides and that of compound 11 is excreted in urine as a N-glucuronide involving its pyrazole moiety. The urinary excretion profiles of the epimeric and 18-nor-17,17-dimethyl-13(14)-ene steroids are presented and discussed on the basis of their structural features.

Salivary progesterone for the assessment of the ovarian function in the capuchin monkey (Cebus apella)

Salivary and plasma progesterone were measured in normally cycling (n=10) and castrated (n=4) femaleCebus monkeys (Cebus apella). During the follicular phase, progesterone levels in saliva ranged between 0.05 and 1.40 ng/ml and in the luteal phase they increased to between 0.22 and 4.70 ng/ml. These values represented on average 6.5 and 3.2% of those values measured in plasma, for the follicular and luteal phases, respectively. The regression analysis of the steroid concentrations in both fluids showed a highly significant correlation (r=0.8985,n=180,P<0.0001). Ovariectomized monkeys had consistently low salivary (0.37±0.02 ng/ml) and plasma (4.70±0.25 ng/ml) progesterone, showing a low, but significnat, correlation coefficient (r=0.2592,n=58,P=0.047). The ratio of plasma/salivary progesterone was significantly higher in the luteal phase (31.09±1.65) than in the follicular phase (23.06±2.26) and in castrated monkeys (16.00±1.38). The free fraction of progesterone constituted 5.3±0.2% of the total plasma progesterone during the follicular phase and 3.3±0.1% during the luteal phase. Ovariectomized monkeys showed a significantly higher percentage of free progesterone in plasma (7.7±0.1%). In contrast, free progesterone made up 64.4 and 70.9% of the total salivary progesterone for the follicular and luteal phases, respectively. The proportion of free progesterone in castrated animals was within the range observed in cycling animals. We suggest that the levels of progesterone in the saliva of capuchin monkey follow a pattern similar to that for plasma progesterone, reflecting the free steroid fraction. Thus, the measurement of such steroid in saliva may offer a valuable alternative to plasma determinations for the assessment of the ovarian function inCebus and probably other New World monkey species.

Sex hormone-binding globulin. Binding to cell membranes and generation of a second messenger.

I n plasma, most steroid hormones are largely bound and transported by two specific steroid-hormone-binding proteins, corticosteroid-binding globulin (CBG) and sex hormone-binding globulin (SHBG) (Siiteri et al, 1982; Englebienne, 1984; Westphal, 1986; Rosner, 1986; Brien, 1981; Mercier-Bodard et al, 1981). Although it is an oversimplification (see Mendel, 1989), it is fair to state that the prevailing view of the function of these proteins is to bind steroids and thus trap them in the plasma compartment. Only a small fraction of free steroids are available to diffuse passively out of the capillary bed and across cell membranes to initiate hormonal effects. The best evidence supports this notion of how steroid hormones exit the vascular space and enter cells. In the past few years, however, there is undeniable evidence of additional functions for the steroidbinding proteins. The major lines of evidence that led to this conclusion are reviewed here.

A method for characterization of endogenous ligands to orphan receptors belonging to the steroid hormone receptor superfamily—Isolation of progesterone from pregnancy plasma using progesterone receptor ligand-binding domain

An analytical method is described whereby progesterone is isolated from pregnancy plasma on the basis of the high affinity and specificity of the progesterone receptor for its ligand. Partially purified progesterone receptor ligand-binding domain, expressed as a protein A fusion protein in Escherichia coli, is incubated with a neutral steroid fraction obtained by extraction and ion-exchange chromatography of human late-pregnancy plasma. The incubated sample is passed through two Lipidex 1000 (lipophilic gel) beds. The first, at 4°C, separates the specific ligand-fusion protein complex from nonspecifically bound and unbound compounds, and the second, at 40°C, separates the specific ligand from the protein. Elution of the second bed with methanol yields a fraction containing specific ligand that can be characterized by gas chromatography-mass spectrometry. This methodology may be valuable for identification of endogenous ligands to orphan receptors of the steroid hormone receptor superfamily.

The detection of danazol and its significance in doping analysis.

The use of anabolic steroids and related compounds in sport is forbidden by the International Olympic Committee (IOC). Because danazol (17 alpha-pregna-2,4-dien-20-yno[2,3-D] isoxazol-17 beta-ol) is structurally related to the anabolic steroid stanozolol, its use should be questioned. Therefore, the detection and the significance of danazol in doping analysis are discussed. A urine specimen suspected of containing danazol metabolites was analyzed in order to characterize the metabolites. After isolation and conversion into three different derivatives, the metabolites were subjected to gas chromatography/mass spectrometry (GC/MS) in the electron impact (EI) mode. The structure assignment was based on the molecular ions, fragmentation patterns observed for the three different derivatives, and the possible metabolite structures given in the literature. Ethisterone was identified as a nonconjugated metabolite. 2-Hydroxymethylethisterone was observed in two stereoisomeric forms. One stereoisomer was found mainly in the nonconjugated steroid fraction and the other in the conjugated fraction. The results were confirmed by analyzing urine specimens of a volunteer who was known to have taken danazol. Derivatization methods and GC/MS data are given to implement danazol detection in routine screening and confirmation procedures.

Gastrointestinal metabolism of contraceptive steroids

A number of oral contraceptive steroids undergo first-pass metabolism in the gastrointestinal mucosa. Ethinyl estradiol (mean systemic bioavailability 40% to 50%) is extensively metabolized, principally to a sulfate conjugate. In vivo studies that use portal vein catheterization and the administration of radiolabeled ethinyl estradiol have shown that the fraction of steroid metabolized in the gut wall is 0.44. In vitro studies with jejunal biopsy samples or larger pieces of jejunum or terminal ileum mounted in Ussing chambers have indicated that more than 30% of added ethinyl estradiol is sulfated. The progestogen desogestrel is a prodrug that is converted to the active metabolite 3-ketodesogestrel. Substantial first-pass metabolism of desogestrel occurs in the gut mucosa, with evidence from Ussing chamber studies for the formation of the active metabolite. Another progestogen, norgestimate, is also metabolized by the gut wall in vitro of which the principal metabolite is the deacetylated product, norgestrel oxime. It seems very likely that this will also occur in vivo. Drug interactions occurring in the gut wall have been reported with ascorbic acid (vitamin C) and paracetamol.

Studies on anabolic steroids. VII Analysis of urinary metabolites of formebolone in man by gas chromatography—mass spectrometry

The metabolism of formebolone in man is described. After Sep-Pak C 18 extraction, the free, conjugated and acidic steroids were separated. After enzymatic hydrolysis of the conjugates, the neutral steroids were identified by GC—MS. Two metabolites identified as 2-hydroxymethyl-11α-17β-dihydroxy-17α-methylandrost-1,4-diene-3-one and 11α-hydroxymethyltestosterone were isolated from both the free and conjugated steroid fractions. Ah acidic metabolite identified as 11α,17β-dihydroxy-17α-methyl-3-oxo-androsta-1,4,-diene-2-carboxylic acid was isolated from the free steroid fraction. This acidic steroid was stable when derivatized as the methyl ester—TMS ether derivative but its TMS ester—TMS ether derivative progressively degraded to yield the 17-mono and 11,17-di-O-TMS ether derivatives of 11α-hydroxymethandienone. The GC—MS features of formebolone metabolites are presented and its routes of biotransformation are discussed.

Studies on anabolic steroids—6. Identification of urinary metabolites of stenbolone acetate (17β-acetoxy-2-methyl-5α-androst-1-en-3-one) in human by gas chromatography/mass spectrometry

The metabolism of stenbolone acetate (17β-acetoxy-2-methyl-5α-androst-1-en-3-one), a synthetic anabolic steroid, has been investigated in man. Nine metabolites were detected in urine either as glucuronic or sulfuric acid aglycones after oral administration of a single 50 mg dose to a male volunteer. Stenbolone, the parent compound, was detected for more than 120h after administration and its cumulative excretion accounted for 6.6% of the ingested dose. Most of the stenbolone acetate metabolites were isolated from the glucuronic acid fraction, namely: stenbolone,3α-hydroxy-2-methy-5α-androst-1-en-17-one, 3α-hydroxy-2ξ-methyl-5α-androstan-17-one; 3 isomers of 3ξ,16ξ-dihydroxy-2-methyl-5α-androst-1-en-17-one; 16α and 16β-hydroxy-2-methyl-5α-androst-1-ene-3,17-dione; and 16ξ,17β-dihydroxy-2-methyl-5α-androst-1-en-3-one. Only isomeric metabolites bearing a 16α or a 16β-hydroxyl group were detected in the sulfate fraction. Interestingly, no metabolite was detected in the unconjugated steroid fraction. The steroids identities were assigned on the basis of their TMS ether, TMS enol-TMS ether, MO-TMS and d 9-TMS ether derivatives and by comparison with reference and structurally related steroids. Data indicated that stenbolone acetate was metabolized into several compounds resulting from oxidation of the 17β-hydroxyl group and/or reduction of A-ring δ-1 and/or 3-keto functions with or without hydroxylation at the C 16 position. Finally, comparison of stenbolone acetate urinary metabolites with that of methenolone acetate shows similar biotransformation pathways for both δ-1-3-keto anabolic steroids. This indicates that the position of the methyl group at the C 1 or C 2 position in these steroids has little effect on their major biotransformation routes in human, to the exception that stenbolone cannot give rise to metabolites bearing a 2-methylene group since its 2-methyl group cannot isomerize into a 2-methylene function through enolization of the 3-keto group as previously observed for methenolone.

Steroids of the Marine Sponge Cinachyra tarentina: Isolation of Cholest-4-ene-3,6-dione and (24R)-24-Ethylcholest-4-ene-3,6-dione

Assmcr.-The MeOH extract of the demospongia Cinacbyra tamtina was shown to contain, in addition to three common 3~-hydroxysterols and three cholest-4-en-3-ones, two steroids: cholest-4-ene-3,6-dione Ell and (24R)-24-ethylcholest-4-ene-3,6dione 121, which have not been previously found as naturally occurring compounds. The structures of 1 and 2 have been elucidated by spectroscopic analyses ('H and 13C-nmr, uv, ir) and confirmed via synthesis. Marine sponges are a rich source of unusual sterols, including the cholest-4en-3-ones that were first encountered in the sponge Stelleta ckzrella (1). These sterols have been isolated from sponges occurring in several parts of the world; sometimes the enone function is further conjugated with additional carbon-carbon and carbon-oxygen double bonds as in cholesta-4,7,22-triene-3,6-dione, 24methylcholesta-4,7,22-triene-3 ,6dione, and 24-ethylcholesta-4,7,22-triene-3,6dione, which are present in the sponge Rapbidostila incisa (2); 24-methylcholesta4,24(28)-diene-3,6-dione and cholesta4,22-diene-3,6-dione, present in the sponge Antboarcuata g~acea (3); and (22E>cholesta-4,6,8( 14), 22- tetraen- 3one recently isolated from the sponge Dirtyonella incisa (4). As part of our continuing research on the metabolites from Mediterranean organisms, we examined the steroid fraction of the demospongia Ciwbyra tarentitza (Pulitzer-Finali) (Porifera). This sponge has a hemispherical shape more or less flattened with a wide base of attachment; the color in life is light yellowish brown, and the consistency, in spite of the strong radiating bundles of oxeas, is weak (5). This study led to the identification of three common 3P-hydroxysterols [cholesterol, 24-methylcholesta-5-22-dien3p-01, and 24-methylcholesta-5-24(28> dien-3P-011, three cholest-4-en-3-ones Echolest-4-en- 3 -one, 24-methylcholesta4,24(28)-dien-3-one, and 24-methylcholesta-4,22-dien-3-o1ie], and two cholest-4-ene-3,6-diones, 1 and 2. Compounds 1 and 2 until now have not been reported as naturally occurring compounds.

Gastrointestinal metabolism of contraceptive steroids

A number of oral contraceptive steroids undergo first-pass metabolism in the gastrointestinal mucosa. Ethinyl estradiol (mean systemic bioavailability 40% to 50%) is extensively metabolized, principally to a sulfate conjugate. In vivo studies that use portal vein catheterization and the administration of radiolabeled ethinyl estradiol have shown that the fraction of steroid metabolized in the gut wall is 0.44. In vitro studies with jejunal biopsy samples or larger pieces of jejunum or terminal ileum mounted in Ussing chambers have indicated that more than 30% of added ethinyl estradiol is sulfated. The progestogen desogestrel is a prodrug that is converted to the active metabolite 3-ketodesogestrel. Substantial first-pass metabolism of desogestrel occurs in the gut mucosa, with evidence from Ussing chamber studies for the formation of the active metabolite. Another progestogen, norgestimate, is also metabolized by the gut wall in vitro of which the principal metabolite is the deacetylated product, norgestrel oxime. It seems very likely that this will also occur in vivo. Drug interactions occurring in the gut wall have been reported with ascorbic acid (vitamin C) and paracetamol.