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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The intraovarian axis between granulosa cells and thecal cells is regulated by locally produced autocrine and paracrine factors. Until now, microvascular endothelial cells (MVEC) have not been included in such studies. Bovine granulosa cells from medium-sized antral follicles were plated at low density into the lower compartment of 24-well-culture plates on day 0. MVEC derived from bovine corpus luteum were seeded on appropriate inserts and placed as the upper compartment on day 1. Control granulosa cell cultures and MVEC co-cultures were maintained in serum-containing medium. On day 21, control cultures displayed an epithelioid monolayer and the coculture displayed a multilayer. Histochemical staining for 3 beta-HSD activity and for the lipid droplet stain with the fluorescent dye Nile Red were strong, suggesting augmented steroidogenesis in the multilayer. Yet the progesterone levels of supernants corrected for 10,000 cells were similar in monolayers and in multilayers. Co-cultures contained approximately three times more granulosa cells than control cultures as evaluated with a Coulter counter. Additionally, the occurrence of dead cells was quantified with the fluorescent DNA stain, ethidium homodimer, in 11-day-old control cultures and MVEC co-cultures which were deprived of serum, MVEC, or both for an additional 40 h. Serum and MVEC suppressed the occurrence of granulosa cell death. It is concluded that MVEC produce survival factors for the growth and maintenance of granulosa cells.
Mol Cell Endocrinol 1994 Aug
PMID:Long-term co-culture of bovine granulosa cells with microvascular endothelial cells: effect on cell growth and cell death. 782 2

In many studies it has been documented that the induction of multiple follicular growth in humans results in an asynchrony between the degree of cumulus mucification, oocyte meiotic maturation, fertilizability, and follicular cell progesterone (P4) secretion. The present study was carried out on oocytes enclosed in fully mucified cumulus. Thus, oocyte fertilizability was correlated to human cumulus cell (hCC) and human granulosa-lutein (G-L) cell competence for P4 secretion in culture. In the G-L cells, P4 secretion and percentage of cells manifesting 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity increased concurrently with the period of culture. In the hCC, however, P4 secretion decreased concurrently with elongation of the culture period, whereas the percentage of 3 beta-HSD-positive cells increased. In hCC corresponding to the fertilized oocytes, P4 accumulation in culture medium was 1.9-fold (P < 0.001) and 1.6-fold (P < 0.02) higher on days 0-3 and 3-5 of culture, respectively, as compared to P4 accumulation in hCC of unfertilized oocytes. Also, in hCC corresponding to the fertilized oocytes, the degree of 3 beta-HSD activity was found to be significantly higher shortly after aspiration and after either 3 or 5 days, compared to hCC of unfertilized oocytes. In the G-L cells pooled from all follicles yielding mature cumulus-oocyte complexes, P4 accumulation and percentage of 3 beta-HSD-positive cells increased concurrently with the increase in percentage of fertilized eggs of each individual woman. These results indicate that in stimulated cycles, follicles yielding mature cumulus-oocyte complex, oocyte fertilizability, and G-L cell or hCC competence for P4 secretion are correlated and synchronous.
J Steroid Biochem Mol Biol 1994 Dec
PMID:Increasing progesterone secretion and 3 beta-hydroxysteroid dehydrogenase activity of human cumulus cells and granulosa-lutein cells concurrent with successful fertilization of the corresponding oocyte. 782 92

Two isoenzymes are responsible for 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4-isomerase (3 beta-HSD) activity in humans. We analyzed the structure of types I and II 3 beta-HSD genes in a male pseudohermaphrodite suffering from a severe salt-losing form of congenital adrenal hyperplasia. We did not detect any mutation in the type I 3 beta-HSD gene, but we found two different missense mutations in exon IV of the type II 3 beta-HSD gene of the patient; a conversion of codon Leu108 into a Trp (L108W) inherited from his mother and a conversion of codon Pro186 into a Leu (P186L) inherited from his father. We assessed the effect of the L108W and P186L mutations on 3 beta-HSD activity by in vitro analysis of mutant enzymes expressed in heterologous COS-1 cells. Using homogenates from transfected cells, the Km values for PREG were 7 +/- 2 and 8 +/- 2 microM for the recombinant L108W and P186L enzymes, respectively, compared with 2.2 +/- 0.2 microM for the normal type II 3 beta-HSD enzyme. Moreover, Km values for NAD+ were much higher for the L108W and P186L proteins, being 678 +/- 166 and 920 +/- 351 microM, respectively, compared with 24 +/- 3 microM for the normal type II 3 beta-HSD enzyme. Vmax values for PREG and NAD+ were lower for both mutant enzymes; thus, the in vitro overall efficiency, relative to the normal enzyme, is approximate as 0.3% and 0.2% for the L108W and P186L enzymes, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Hum Mol Genet 1994 Sep
PMID:Functional characterization of the novel L108W and P186L mutations detected in the type II 3 beta-hydroxysteroid dehydrogenase gene of a male pseudohermaphrodite with congenital adrenal hyperplasia. 783 23

11 beta-Hydroxysteroid dehydrogenase (11 beta-HSD) catalyses the metabolism of corticosterone to inert 11-dehydrocorticosterone, thus preventing glucocorticoid access to otherwise non-selective renal mineralocorticoid receptors (MRs), producing aldosterone selectivity in vivo. At least two isoforms of 11 beta-HSD exist. One isoform (11 beta-HSD1) has been purified from rat liver and an encoding cDNA cloned from a rat liver library. Transfection of rat 11 beta-HSD1 cDNA into amphibian cells with a mineralocorticoid phenotype encodes 11 beta-reductase activity (activation of inert 11-dehydrocorticosterone) suggesting that 11 beta-HSD1 does not have the necessary properties to protect renal MRs from exposure to glucocorticoids. This function is likely to reside in a second 11 beta-HSD isoform. 11 beta-HSD1 is co-localized with glucocorticoid receptors (GRs) and may modulate glucocorticoid access to this receptor type. To examine the predominant direction of 11 beta-HSD1 activity in intact mammalian cells, and the possible role of 11 beta-HSD in regulating glucocorticoid access to GRs, we transfected rat 11 beta-HSD1 cDNA into a mammalian kidney-derived cell system (COS-7) which has little endogenous 11 beta-HSD activity or mRNA expression. Homogenates of COS-7 cells transfected with increasing amounts of 11 beta-HSD cDNA exhibited a dose-related increase in 11 beta-dehydrogenase activity. In contrast, intact cells did not convert corticosterone to 11-dehydrocorticosterone over 24 h, but showed a clear dose-related 11 beta-reductase activity, apparent within 4 h of addition of 11-dehydrocorticosterone to the medium.(ABSTRACT TRUNCATED AT 250 WORDS)
J Mol Endocrinol 1994 Oct
PMID:'Liver-type' 11 beta-hydroxysteroid dehydrogenase cDNA encodes reductase but not dehydrogenase activity in intact mammalian COS-7 cells. 784 28

We had previously reported that juvenile hormone III (JH III) and the JH analogue 2-(4-phenoxy phenoxy)-ethoxytetrahydropyran exert inhibitory effects on progesterone synthesis by blocking cAMP production in hCG-stimulated MA-10 Leydig tumor cells. In the present study, the effects of JH analogue upon the biosynthetic pathway of progesterone synthesis have been examined. Our results demonstrated that JH analogue inhibited progesterone production even in the presence of 20-hydroxycholesterol or 25-hydroxycholesterol. Furthermore, although JH analogue inhibited pregnenolone production in hCG-stimulated MA-10 cells the activity of the 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) was unaffected. These data suggest that JH analogue might inhibit the steroidogenic pathway in Leydig tumor cells by inhibiting the activity of the cholesterol side chain cleavage (CSCC) enzymatic complex. The JH analogue was also evaluated for inhibitory actions on cholesterol availability. An important effect of this compound was the interference with the cellular process of plasma membrane cholesterol internalization. Moreover, JH analogue inhibited not only the use of cholesterol ester for steroid biosynthesis under Bt2cAMP stimulation, but also the cholesterol ester hydrolase (CEH) activity in MA-10 Leydig tumor cells.
J Steroid Biochem Mol Biol 1995 Jan
PMID:Regulation of the cholesterol ester cycle and progesterone synthesis by juvenile hormone in MA-10 Leydig tumor cells. 785 77

11 beta-Hydroxysteroid dehydrogenase (11 beta-HSD) reversibly converts physiological glucocorticoids (cortisol, corticosterone) to inactive 11-dehydro forms, and thus controls glucocorticoid access to receptors in a variety of tissues. We have cloned a cDNA encoding 'liver-type' 11 beta-HSD (11 beta-HSD1) from the mouse using PCR, and have determined its nucleotide sequence. Mouse 11 beta-HSD1 cDNA showed 91% identity to rat 11 beta-HSD1 cDNA. There was 87% amino acid identity with rat 11 beta-HSD1 with conservation of the putative cofactor and substrate binding domains. Northern blot analysis of mouse tissues demonstrated abundant 11 beta-HSD1 message in the liver, kidney and lung, with lower expression in brain subregions and gonads. 11 beta-HSD1 mRNA was below the level of detection in the murine colon. 11 beta-HSD1 mRNA levels in kidney was higher in males than in females, but in contrast to the rat, there was no sexual dimorphism in the mouse liver. Although males and females showed different mRNA levels in the kidney, there was no sex difference in 11 beta-HSD enzyme activity. Thus, despite the high inter-species conservation of 11 beta-HSD1, there are clear species and tissue-specific differences in its expression.
J Steroid Biochem Mol Biol 1995 Feb
PMID:Cloning, sequencing and tissue-distribution of mouse 11 beta-hydroxysteroid dehydrogenase-1 cDNA. 787 49

The metabolism of dehydroepiandrosterone (DHA) and androstenedione (A-dione) was studied in cultured human adipose stromal cells obtained from breast tissue of six premenopausal patients undergoing reduction mammoplasty. Cells were maintained in culture in the presence of 10% fetal bovine serum. Studies were carried out during the proliferative and confluent phases of culture with radiolabelled substrates (2 microCi, 10 nM). During the early phases of replication 7 alpha-hydroxydehydroepiandrosterone (7 alpha-OHDHA) was formed from DHA. As the cells reached confluence, the major metabolite of DHA in cells from all patients was A-dione indicating the presence of 3 beta-hydroxysteroid dehydrogenase/isomerase (3 beta-HSD). The conversion of DHA to A-dione was variable among patients when cells were confluent with 30-80% of substrate being metabolized to this product. Adipose stromal cells synthesized estrone (E1) from DHA once A-dione formation was established. Under basal conditions E1 was obtained in cells from three of the six patients examined with up to 36% substrate converted to this product. Dexamethasone (Dex 10(-7) M) stimulated E1 formation in cells from all subjects with up to 50% of substrate being converted. Parallel studies comparing the conversion of DHA with A-dione to E1 revealed that as the cells became confluent, E1 formation from both substrates was similar. The pattern of steroid metabolism was also examined in primary culture and in subculture. Passage 1 cells continued to form A-dione as a major metabolite of DHA, and did not revert to the pattern of metabolism found in primary cells during the early stages of replication, when 7 alpha-hydroxylation predominated. Human adipose stromal cells actively metabolize DHA, producing 7 alpha-OHDHA, A-dione and E1 as principal metabolites. Changes in the circulating levels of DHA may directly influence the formation of E1 in peripheral tissues. This source of E1 will be modulated by factors controlling 3 beta-HSD and aromatase activities.
J Steroid Biochem Mol Biol 1995 Feb
PMID:Estrone formation from dehydroepiandrosterone in cultured human breast adipose stromal cells. 787 53

Using cultured human fetal adrenal cells, we have investigated the basal secretion of cortisol and dehydroepiandrosterone sulfate (DHAS) and the effect of corticotropin (ACTH), angiotensin-II (A-II) and transforming growth factor beta 1 (TGF beta 1) on the secretion of these steroids and on the mRNA levels of ACTH receptor (ACTHR), cytochrome P-450scc (cholesterol side-chain cleavage), P450 17 alpha (17 alpha-hydroxylase/17-20 lyase) and 3 beta-HSD (3 beta-hydroxysteroid dehydrogenase). The basal DHAS/cortisol ratio declined progressively between 12.5 and 21 weeks. ACTH treatment enhanced the secretion of cortisol and to a lesser extent that of DHAS, and increased the steroidogenic response to an acute stimulation with ACTH. These changes were associated with increased mRNA levels of ACTHR and of the steroidogenic enzymes. A-II treatment also increased the secretion of both DHAS and cortisol, but less than ACTH, enhanced the responsiveness to ACTH and increased ACTHR, P450scc and P450 17 alpha mRNA levels. In contrast, TGF beta 1 alone or together with ACTH decreased DHAS secretion, but not cortisol secretion. Moreover, TGF beta 1 had no effect on ACTHR and P450scc mRNA levels, decreased by about 50% the mRNA levels of P450 17 alpha both in the absence or presence of ACTH, but enhanced the stimulatory effects of ACTH on 3 beta-HSD mRNA. These results, along with those previously reported, suggest that both A-II and TGF beta may play a role in fetal adrenal function. In addition, they show that the effects of both peptides are qualitatively different from, even sometimes opposite to, those previously reported in bovine and ovine adrenal cells.
Mol Cell Endocrinol 1994 Dec
PMID:Regulation of corticotropin and steroidogenic enzyme mRNAs in human fetal adrenal cells by corticotropin, angiotensin-II and transforming growth factor beta 1. 789 1

We have previously identified and purified a splenocyte-derived factor (PSF) that stimulates the accumulation of progesterone and 20 alpha-dihydroprogesterone (20 alpha-OH-P) in rat ovarian granulosa cells independently of FSH. In the present study, time course experiments comparing the response to PSF with that to FSH revealed that PSF-stimulated progesterone accumulation was slower than that of FSH, but PSF-stimulated 20 alpha-OH-P accumulation had a time course similar to that of FSH. To determine the basis for the slower progesterone response to PSF, the effect of these two agents on each step of the steroidogenic pathway was assessed. First, to examine whether PSF-stimulated cholesterol mobilization was limiting, cultured granulosa cells were treated with 22(R)-hydroxycholesterol. While both FSH- and PSF-stimulated progesterone and 20 alpha-OH-P accumulation approximately doubled, the overall time courses did not change indicating that cholesterol availability was not the factor limiting the response to PSF. Next, PSF and FSH induction of steroidogenic enzyme activities and messenger RNAs were compared. While FSH-stimulated cytochrome P450 side chain cleavage enzyme (SCC) activity rapidly increased (peaking at 2 days) and then slowly declined, PSF-stimulated SCC activity gradually increased over 5 days to approximately 35% of the maximal activity stimulated by FSH. PSF also induced slower increases in P450scc mRNA levels than did FSH. In addition, PSF stimulated 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity more slowly than did FSH, but after 3 days of culture, PSF-stimulated activity was significantly higher than that induced by FSH.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Cell Endocrinol 1994 Dec
PMID:Induction of rat granulosa cell steroidogenic enzyme activities and their messenger ribonucleic acids by a splenocyte-derived factor. 789 3

Among the large number of immediate early genes, nuclear proto-oncogenes of the Fos and Jun families, have been postulated to be involved in the long-term effects of several growth factors on cell differentiation and/or multiplication. Since adrenal cell differentiated functions appear to be regulated by specific hormones and growth factors, the effects of these factors on proto-oncogene mRNA levels were analysed in bovine adrenal fasciculata cells (BAC) in culture. Corticotropin (ACTH) and insulin-like growth factor I increased c-fos and jun-B mRNA, but had no effect on c-jun mRNA and these early changes were associated with a later increase in BAC specific function [ACTH receptors, cytochrome P450 17 alpha) and 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD)] and an enhanced steroidogenic responsiveness to both ACTH and angiotensin-II (A-II). On the other hand, A-II increased the three proto-oncogene (c-fos, c-jun and jun-B) mRNAs, induced a decrease of P450 17 alpha and 3 beta-HSD and caused a marked homologous and heterologous (ACTH) densitization. Transforming growth factor beta 1 which only increased jun-B mRNA, markedly reduced BAC differentiated functions and the steroidogenic responsiveness to both ACTH and A-II. Thus, it is postulated that the proto-oncoproteins encoded by the immediate early genes may play a role in the long-term effects of peptide hormones and growth factors on BAC differentiated functions.
J Steroid Biochem Mol Biol 1994 Sep
PMID:Peptide hormone and growth factor regulation of nuclear proto-oncogenes and specific functions in adrenal cells. 791 7


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