Steroidogenesis by the immature rhesus monkey ovary in vitro

Primates are believed to have a low level of ovarian steroidogenic activity during prepubertal development. In order to study the rate limiting factors associated with the low level of steroidogenesis, ovaries from prepubertal rhesus monkeys were quartered and incubated for 48 h at 37 C in minimum essential medium. These ovaries secreted 687 +/- 347 pg estradiol/mg ovary and 299 +/- 35 pg progesterone/mg ovary during 48 h of incubation. The addition of 100 ng luteinizing hormone (LH) or 1 mM dibutyryl (Bu)2 cAMP failed to increase significantly estradiol or progesterone secretion. Furthermore, the addition of either progesterone or androstenedione failed to augment estradiol secretion. The presence of either LH or (Bu)2 cAMP with the steroidal substrates also failed to augment estradiol secretion. In contrast, the addition of (Bu)2 cAMP with lipoprotein-derived cholesterol significantly stimulated a two-fold increase in progesterone secretion. The presence of LH in the lipoprotein-supplemented medium failed to augment progesterone secretion. These results suggest that prepubertal monkey ovaries lack the ability to respond to LH, probably due to a lack of gonadotropin receptors or failure of the receptor to stimulate cAMP synthesis. Furthermore, the failure of progesterone and androstenedione to augment estradiol secretion suggests that some cellular components needed to induce aromatase activity are not functional in the prepubertal primate ovary.     

Steroidogenesis in rabbit preimplantation embryos.

Rabbit preimplantation embryos were flushed from the reproductive tract at 24 hr (1- to 2-cell stage), 48 hr (morula), 72 hr (morula), 96 hr (blastocyst), 120 hr (blastocyst), and 144 hr (blastocyst) post coitum. At 168 hr (early postimplantation period), gestation sacs were excised, frozen, and sectioned in a cryostat. Delta5-3beta-Hydroxysteroid dehydrogenase [3(or 17)beta-hydroxysteroid:NAD(P) oxidoreductase, EC 1.1.1.51] activity was determined histochemically in whole preimplantation embryos and in sectioned postimplantation embryos. 3beta-Hydroxysteroid dehydrogenase activity began at 48 hr and was sustained through the late blastocyst stage (144 hr), with the exception of a brief drop, possibly cessation, of activity at 72 hr. There was no activity at 168 hr. Since 3 beta-hydroxysteroid dehydrogenase is a key enzyme in the metabolism of steroid hormones, its presence is strong evidence for steroidogenesis. Only 144-hr preimplantation embryos were used to determine 17 beta-hydroxysteroid dehydrogenase (estradiol-17beta:NAD 17-oxidoreductase, EC 1.1.1.62) activity, which was present, suggesting synthesis of estrogen. By means of radioimmunoassay, 144-hr preimplantation embryos were found to contain estradiol-17beta. Other authors have shown that rabbit blastocysts contain progesterone and other steroids, and these embryos can synthesize steroids from non-steroid and steroid precursors. Therefore, our results plus those of others prove that rabbit preimplantation embryos synthesize steroid hormones. Our present and previous results (with rats, hamsters, and mice) suggest that the steroid hormones synthesized by the embryo are critical for preimplantation embryogenesis and for implantation of the lbastocyst.     

Steroidogenesis in human polycystic ovary

Polycystic ovarian disease (PCOD) is a heterogenous condition with a broad clinical and pathologic spectrum that may reflect the effects of diverse etiologic factors. Depending on the diagnostic data available from patients, various steroidogenic enzyme blocks have been postulated, mostly implicating higher-than-normal production of circulating delta 4-androstenedione, testosterone, and, in some cases, dehydroisoandrosterone. These high levels of androgens, because of their peripheral conversion to estrogens, lead to inappropriate secretion of gonadotropins in PCOD. Whatever may be the etiologic factors, the common entity is a polycystic ovary. Such an ovary contains preantral follicles, few antral follicles, many atretic follicles, and follicular and degenerative cysts. The follicles lack a sufficient number of mature granulosa cells to produce enough estrogens. On the other hand, there is a hypertrophy of stromal and thecal tissue continuously producing androgens. The steroid analysis of the follicular fluid obtained from the cystic follicles of the polycystic ovary revealed high concentration of delta 4-androstenedione and absence of, or only minute amounts of, estrogens. Early studies of biosynthesis of steroids in the polycystic ovary demonstrated conversion of progesterone mainly to androgens. Arising from these observations was the suggestion that an aromatase enzyme block existed. That suggestion was corroborated in the findings of higher-than-normal circulating androgens in PCOD. Later, other partial enzymatic blocks of beta-hydroxydehydrogenase and 17-hydroxylase were also suggested. However, it is known that the therapies such as wedge resection, administration of FSH, or FSH/LH (Pergonal) and LHRH leads to ovulation and, in most cases, normal cyclicity in the polycystic ovary. The knowledge gained from these therapies clearly indicates that the enzymatic blocks or abnormal steroidogenesis in the polycystic ovary may be due to the absence of proper gonadotropin response, and the main defect may be at the hypothalamic-pituitary axis. In PCOD with hyperinsulinemia, insulin and IGF-I have been implicated in the production of androgens by the polycystic ovary. The mechanism of the action of insulin or IGF-I is not yet known, however.     

Steroidogenesis in isolated adrenal cells: excitation by calcium.

Calcium salts were found to replace ACTH in inducing steroidogenesis in isolated adrenocortical cells from rats. This Ca-specific stimulation occurred when the cation was presented to the cells in the presence of phosphate and carbonate as a counter-ions under conditions which favoured the formation of colloidal calcium. Colloid generation and stabilization was facilitated by the use of calcium buffers and gelatin. Stable soluble or sparingly soluble calcium complexes were inactive. The preparation of cells and metastable calcium solutions is described in detail. The Ca trigger was sensitive to Ca deprivation or inhibitors of Ca transport and could be replced by Sr. The relative role of Ca and cyclic AMP as second messengers is discussed.     

Nodular cerebral sarcoidosis simulating metastatic carcinoma

A 51-year-old woman with known sarcoidosis was admitted to the hospital with grand mal seizures. The enhanced cranial computed tomographic (CT) scan showed bilateral, discrete, nodular lesions simulating metastatic carcinoma. Results of a workup for malignant neoplasm and inflammatory disorders were normal. Diagnosis of nodular cerebral sarcoidosis was made, and the patient received prednisone therapy. After four months of therapy, the CT scan showed resolution of the nodules.     

Steroidogenesis in zebrafish and mouse models

Steroid hormones regulate physiological homeostasis for salt, sugar, and sex differentiation. All steroids are synthesized from a common precursor, cholesterol, in a step that converts cholesterol to pregnenolone. The enzyme carrying out this first conversion step is CYP11A1. To further investigate the importance of steroid biosynthesis, animal models with defects in the Cyp11a1 gene are used. Mice with targeted disruption of the Cyp11a1 gene produce no steroids with severe adrenal defects. These mice survive during embryogenesis, but die after birth. Zebrafish with a block in cyp11a1 gene function has an earlier defect, presumably because it lacks adequate maternal steroid supply. When cyp11a1 activity was compensated by the injection of antisense morpholino oligos, the embryos have shortened axis and a defect of epibolic cell movement during early embryogenesis. The discovery of steroid function in cell movement is novel, and should provide new insights into our understanding of diverse functions of steroids.     

Connective tissue formation by lung fibroblasts in vitro.

Guinea pig lung fibroblasts were grown in monolayer culture after enzymatic disaggregation of lung parenchyma. Light and electron microscopy indicated that the cultures were relatively homogeneous with respect to cell type. Synthesis of matrix glycosaminoglycans and collagen was demonstrated throughout the life of the culture. The properties of the guinea pig cell strains make these a suitable in vitro model system for studying the regulation of connective tissue metabolism of pulmonary tissue.     

Steroidogenesis and extracellular cAMP accumulation in adrenal tumor cell cultures.

ACTH stimulated steroidogenesis and cAMP (adenosine 3',5'-monophosphate) accumulation in an adrenocortical mouse tumor cell line (clone Y1) with Kd values which differed by more than one order of magnitude (5.2 X 10(-11) M and 7 X 10(-10) M, respectively). All of the cAMP formed in response to added ACTH appeared extracellularly in 5- or 30-min incubations. ACTH, at 5 and 10 muU/ml, stimulated steroidogenesis to 25% and 40% of maximum activity; and increased the extracellular accumulation of cAMP 1.4-fold and 2.3-fold, respectively. The effects of ACTH appeared to be via an action on intracellular ATP, specific for cAMP and dependent on an ACTH-sensitive adenylate cyclase system. These observations indicate that ACTH increases cAMP accumulation in Y1 cells at virtually all steroidogenic concentrations and suggest that cAMP is an essential component of ACTH-stimulated steroidogenesis.     

Soft tissue sarcoma metastatic to pleura

Almost all cancers can cause distant pleural metastases. However, pleural metastases of soft tissue sarcoma that constitute less than 1% of adult solid malignancy are extremely rare. It is very difficult to distinguish them form sarcomatous malignant mesothelioma on histopathological features. We report a 57 year-old man who presented to us with left chest pain and progressive dyspnea and was diagnosed to have a pleural metastases of soft tissue sarcoma by thoracoscopic biopsy.     

Steroidogenesis in Fundulus heteroclitus. I. Production of 17 alpha-hydroxy,20 beta-dihydroprogesterone, testosterone, and 17 beta-estradiol by prematurational follicles in vitro

In order to understand better the mechanism of gonadotropin action on steroidogenesis in prematurational follicles of Fundulus heteroclitus, follicle synthesis of 17 alpha-hydroxy, 20 beta-dihydroprogesterone (17 alpha-OH,20 beta-DHP), testosterone (T), and 17 beta-estradiol (E2) from a variety of precursors and the maturational response of oocytes were simultaneously followed in vitro. The addition of 25-hydroxycholesterol, pregnenolone, or progesterone to unstimulated follicles increased media 17 alpha-OH,20 beta-DHP, T, and E2, as well as oocyte germinal vesicle breakdown (GVBD) in a dose-dependent manner. Inhibition of cholesterol side-chain cleavage by aminoglutethimide blocked 25-hydroxycholesterol-promoted steroid accumulation and GVBD, indicating that 25-hydroxycholesterol does not directly induce GVBD, but rather is metabolized in the follicle to an active steroid (presumably 17 alpha-OH,20 beta-DHP). Likewise, trilostane, an inhibitor of delta 5-3 beta-hydroxysteroid dehydrogenase, blocked pregnenolone action. Both inhibitors also completely abolished steroid accumulation and GVBD promoted by a F. heteroclitus pituitary extract (FPE), but not GVBD induced by exogenous 17 alpha-OH,20 beta-DHP. FPE also significantly depressed T but enhanced E2 production from exogenous precursors. We have concluded from these observations that (1) cholesterol side-chain cleavage and pregnenolone conversion to progesterone are essential for gonadotropin-promoted follicle steroid production and the resulting reinitiation of meiosis by the oocyte, (2) the enzymes necessary for the conversion of cholesterol to 17 alpha-OH,20 beta-DHP, T, and E2 are present in the unstimulated, prematurational follicle, and (3) gonadotropin initiates steroidogenesis by acting at a step prior to the conversion of cholesterol to pregnenolone; it also appears to enhance aromatase activity.     

Gynecomastia--an indication of a malignant chorionepithelioma in the male

The course of the disease in a 26-year-old patient showed that also an endocrinological clinical picture may be the basis of a gynaecomastia. Here the symptom gynaecomastia was bilaterally conditioned by a malignant chorion epithelioma. By this tumour a feminisation with gynaecomastia, atrophy of the testicles and positive HCG-test developes. The ascertainment of the diagnosis is possible with the help of the HCG-test. In the early diagnosis of a malignant chorion epithelioma new therapeutic consequences arise by cytostatic drugs.