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Isolated rat islets or RINm5F insulinoma cells treated with interleukin-1 beta (IL-1 beta) for 18 h show reduced glucose-sensitive insulin release and increased nitrite formation as a result of nitric oxide synthase induction. Although a phosphodiesterase inhibitor, isobutylmethylxanthine, potentiated insulin release in response to glucose stimulation, the secretory response was not restored to normal in IL-1 beta-treated islets. Islets that were cultured for 18 h in the presence of IL-1 beta and epiandrosterone (EA) or dehydroepiandrosterone (DHEA) and then washed responded with a concentration-dependent reversal of the effects of IL-1 beta on insulin release in the presence of a glucose or glucose plus isobutylmethylxanthine stimulus. In contrast, when EA and DHEA were not washed from the islets before determination of insulin release, the presence of EA or DHEA inhibited insulin release in both freshly isolated and cultured islets. Nitrite formation in islets and RINm5F cells in response to IL-1 beta was also significantly reduced during culture with EA or DHEA, although nitrite levels were still elevated above control values. Neither steroid affected cell growth or DNA or protein content. Pyrrolidine dithiocarbamate also reduced IL-1 beta-induced nitrite formation. EA and DHEA inhibited [U-14C]glucose oxidation in islets and RINm5F cells. Comparison of [1-14C]glucose and [6-14C]glucose oxidation in islets and RINm5F cells when EA was present during culture and metabolic determination indicated that EA inhibited glycolysis and the pentose shunt contribution to glucose utilization. Neither IL-1 beta in islets nor DHEA in RINm5F cells inhibited pentose shunt activity, although total glucose oxidation and utilization were inhibited. The effects of DHEA and EA on glucose oxidation were rapidly reversible. EA and DHEA reduced glucose-6-phosphate dehydrogenase activity only when added directly to tissue homogenates. Thus, EA and DHEA antagonize the effects of IL-1 beta on beta-cells. Inhibition of glucose metabolism and pentose shunt activity may protect the cells from nitric oxide synthase activation and related toxicities.

Testosterone-4-14C was incubated with minced preputial tissue from adult male rats and the following metabolites were identified: 5α-dihydrotestosterone, 5α-andostane-3β, 17β-diol, 5α-andostane-3α,17β-diol, 3-epiandrosterone, 5α-androsterone, 5α-androstane-3,17-dione and androstenedione. The following metabolites were sought but not found: 5β-dihydrotestosterone, 5β-androsterone, 5β-androstane-3α, 17β-diol and 5β-androstane-3,17-dione. The addition of ATP and pyridine nucleotide cofactors did not significantly affect the amounts of metabolites formed, of which approximately 60% were 5α-dihydro-,20% 17-oxo-,15 % 3β-hydroxyand 5% 3α-hydroxy-C19 steroids. Testosterone- 7α->3H incubated in the presence of TPNH with preputial gland nuclei was metabolized to 5 adihydrotestosterone, 5α-androstane-3β,17β-diol and epiandrosterone: removal of most of the cytoplasm did not reduce the amount of 3β-hydroxysteroids formed relative to 5α-dihydrotestosterone. (Endocrinology 88: 890, 1971)

Explants of ventral prostate glands from intact rats were incubated for 24 hr in culture medium with 3H—androsterone, 3H—epiandrosterone and 3H—dehydroepiandrosterone. Androsterone was partially converted to 5α–androstane–3,17–dione (androstanedione), 17α–hydroxyα5α–androstane–3–one (androstanolone), 5α–androstane–3α,17β–diol (androstanediol) and 5α–androstane–3β,17β–diol (3β–androstanediol). Epiandrosterone was partially converted to 3β–androstanediol. Dehydroepiandrosterone was partially converted to androst–5–ene–3P,17β–diol and epiandrosterone. The latter conversion was likely “direct” (by reduction of the double bond), since neither androstenedione nor androstanedione were found. These results confirm previous findings, showing that in prostate explants in culture, the 3α–hydroxy–steroids are transformed into the corresponding 3–ketones, whereas the 3β–hydroxy—steroids are not, and therefore extend the correlation between the hormonal activities and the metabolic characteristics of androgens. (Endocr...

The monosulfates of testosterone, androsterone, epiandrosterone, dehydroepiandrosterone, androst-5-ene-3β,17β-diol, pregnenolone, pregn-5-ene-3β,20α-diol, and pregn-5-ene-3β,17α,20α-triol and the disulfates of androst-5-ene-3β,17β-diol and pregn-5-ene-3β,20α-diol in the spermatic vein and peripheral blood plasma were quantified. The results show that, in normal subjects, testosterone sulfate, pregnenolone sulfate and possibly androst-5-ene-3β,17β-diol monosulfate are secreted by testis tissue.

The metabolism of testosterone-4-14C by the skin of Wistar rats was followed in three consecutive hair cycles. The major metabolites were Δ4-androstenedione and 5α-dihydrotestosterone; minor products were 5α-androstanedione, 3α-androstanediol, androsterone, epiandrosterone, and 3β-androstanediol. It was observed that the metabolism of testosterone fluctuated during the hair cycles in the hairy skin, but was without significant variations in glabrous skin. The 5α-reductase activity was examined by summing the 14C in the 5α-metabolites. When this activity was expressed in mg of DNA content of skin, an increase was observed in the resting phase of the hair cycle (telogen). The 17β-hydroxysteroid dehydrogenase activity was examined by summing the 14C in the 17-ketometabolites, and the maximal activity was found in the middle of the growing phase (anagen). (Endocrinology 89: 1506, 1971)

Conditions have been established for quantitative assay of rat liver 3²-hydroxysteroid dehydrogenase activity in order to investigate further the difference previously demonstrated (1) in the ratio obtained of epiandrosterone/androsterone, depending on the sex of the animal from which the liver was taken. Livers of male rats have been shown to demonstrate more activity than livers of female rats, whether assays were made using crude homogenates, fractions obtained by differential centrifugation, or acetone-dried preparations. Data were also obtained indicating that rat liver contains separable 3²-hydroxysteroid dehydrogenase activities associated with particulate and soluble material, and the sex difference lies in a greater activity of the 3²-hydroxystcroid dehydrogenase associated with the particulate matter. The activity of the enzj’me associated with the particulate matter can be increased in livers of female rats by administration of testosterone propionate.

The metabolism of testosterone by cultured human fibroblasts derived from the skin of the prepuce, labia majora, abdomen, and the deltoid region of the arm have been studied. Monolayer cultures were incubated with 4-14C-testosterone for 12, 24, 48, 72, and 96 hours in the absence of a NADPH-generating system and the conversion products were recovered from the medium. These studies revealed that testosterone was metabolized very rapidly by cell cultures derived from sex-skins, namely, the foreskin and the labial skin; whereas, cell cultures derived from non-sex skins, the abdominal and the deltoid skin, metabolized testosterone slowly, thus providing proof that the rate of metabolism of testosterone by a serially subcultured cell strain was a function of the anatomical site of the primary explant. The sequence of appearance of conversion products of testosterone deduced from these studies was: androstenedione, androstanedione, androsterone, epiandrosterone and dihydrotestosterone and finally the 3α- and th...

ANDROSTERONE and 3α-hydroxyetiocholan-17-one have been demonstrated to be the principal urinary metabolites of administered testosterone in man (Callow, 1939; Dorfman et al., 1939; Fukushima et al., 1952; and West et al., 1951). Epiandrosterone has been isolated from the urine of a male guinea pig (Dorfman and Fish, 1940) and of a hypogonadal man (Dorfman, 1941) following the administration of testosterone. Since the guinea pig is being used for steroid hormone studies, it would be of interest to know the principal urinary metabolites of testosterone in this species. To this end, testosterone-3-C14 was administered intraperitoneally to a male guinea pig and by the addition of suitable carrier steroids to the urinary extracts, several metabolities of testosterone have been demonstrated. experimental 6 mg. (1.2×106 cts./min./mg.)2 of testosterone -3-C14 prepared by the method of Turner (1950) were administered in corn oil to an 800 gm. male guinea pig.

The cases of 2 girls with precocious sexual hair are described. The urinary C19 steroids were fractionated on an alumina column and by paper chromatography. The results were compared with values from normal children of the same age group determined by the same technique and in the same laboratory. Both patients showed marked quantitative differences for 2 major urinary 11-deoxy-17-ketosteroids. Androsterone (ANDRO) in the 2 affected girls was 6 and 4 times, respectively, the average 24-hr excretion in the urine of the control girls. The urinary etiocholanolone (ETIO) was 3 and 2.5 times, respectively, the value of the controls. Dehydroepiandrosterone (DEA) and epiandrosterone (EPI) were demonstrated in the urine of one of the 2 cases but not in the controls. The values found for urinary 11-ketoandrosterone (11–O-ANDRO), 11-hydroxyandrosterone (11–OH-ANDRO), 11-keto-etiocholanolone (11–O-ETIO) and 11-hydroxyetiocholanolone (11–OH-ETIO) were not appreciably different from the control values.

Mouse kidney homogenate and its subcellular fractions were incubated with [4–14C]— androstenedione (or [4–14C]—testosterone) at pH 6.7 with and without DPNH or TPNH. Epitestosterone was the major metabolite. 5α-Androstane- 3α,17β-diol and testosterone (or androstenedione) were produced in lesser quantities. 17β-Hydroxy- 5α-androstan-3-one, androsterone, epiandrosterone, 5α-androstane-3,17-dione and 5α-androstane-3α, 17β-diol were produced in trace amounts. Trace quantities of 5α-androstane-3α,l7α-diol and 5aandrostane- 3β,17α-diol were indicated as metabolites of androstenedione, but were not conclusively identified. Liver homogenate did not produce epitestosterone from either of the substrates. The reductase activities were localized in the cytosol except that the conversion of androstenedione to testosterone in the DPNH (but not the TPNH) system was localized in the microsomal fraction suggesting separate DPNH- and TPNHspecific 17β-reductase activities. Furthermore, substrate specific DPNH—linked 17β-re...

Two virilized women with gonadal stromal tumors, one histologically an arrhenoblastoma and the other a gynandroblastoma, were investigated. Routine urine steroid analyses showed normal excretion of 17-ketosteroids and 17-ketogenic steroids and a normal response to ACTH administration. Dexamethasone dministration was without major effect on the excretion of 17-ketosteroids. Analyses of plasma neutral steroid sulfates revealed a pattern which was quite similar in these two patients but very different from that seen in normal subjects. Dehydroepiandrosterone sulfate was present in normal concentrations, whereas the levels of androsterone and epiandrosterone sulfates were clearly elevated. Androsterone sulfate was the main plasma neutral steroid sulfate. The oncentrations of androsterone and epiandrosterone sulfates were unaffected by dexamethasone but increased greatly in response to treatment with human chorionic gonadotropin. Testosterone was the main unconjugated steroid secreted by both tumorous ovaries....

THE technique of bovine adrenal perfusion has been utilized in the study of the metabolism of steroids (cf. Hechter et al., 1951). Detailed reports of perfusions with various compounds such as desoxycorticosterone and 17-hydroxy-desoxycorticosterone (Levy et al, 1953) and cortisone (Meyer, 1953a) have been published. In addition several 17-ketosteroids have been perfused under similar conditions. These include androsterone (Hechter et ah, 1950), Δ4-androstene-3,17-dione (Jeanloz et al., 1953), and dehydroepiandrosterone (Meyer et al., 1953). Epiandrosterone (androstane-3β-ol-17-one) was selected for study as the next steroid in this series. This communication is a report of this perfusion and the products isolated from it. Approximately 33% unchanged epiandrosterone (II) was recovered. In addition about 10% androstane-3,17-dione (I) was obtained. 11β-Hydroxylation was also noted, but occurred in a rather limited degree; androstane-11β-ol-3,17-dione (III) and androstane-3β,11β-diol-17-one (IV) were isolate...

The monosulfates of androsterone, dehydroepiandrosterone, epiandrosterone, 5-androstene- 3β,17β-diol, pregnenolone, 5-pregnene-3β,20α-diol and 5-pregnene-3β,17α,20α-triol, as well as the disulfates of 5-androstene-3β,17β-diol and 5-pregnene-3β,20α-diol, were quantified in blood plasma from normal human ovaries and in peripheral blood plasma of 6 patients. In a few instances, the progesterone concentration was determined, too. The results show that the ovaries did not secrete detectable amounts of the steroid sulfates determined. Further, the conjugates circulating in the peripheral blood did not seem to be trapped by the ovaries.