Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.1.1.3 (HSD)
 3,464 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

NADPH-dependent 5 alpha-dihydrotestosterone 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) was purified to apparent homogeneity from mature pig testicular cytosol. The purified enzyme catalyzed the conversion of 5 alpha-dihydrotestosterone (5 alpha-DHT) to 5 alpha-androstane-3 beta, 17 beta-diol. The molecular weight was estimated to be 31 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 28 kDa by gel filtration chromatography, indicating that the native 3 beta-HSD is a monomer. The isoelectric point of the purified enzyme was 5.8 as determined by chromatofocusing. The purified enzyme reduced not only 5 alpha-DHT but also 5 beta-DHT, 5 alpha(or 5 beta)-androstanedione, 5 alpha(or 5 beta)-dihydroprogesterone, prostaglandin E1, 13,14-dihydro-15-keto-prostaglandin F2 alpha, glyceladehyde, xylose and glucuronic acid. Moreover, the enzyme reduced other carbonyl compounds including aromatic aldehydes, aromatic ketones and quinones such as 4-nitrobenzaldehyde, 4-benzoylpyridine, phenylglyoxal, cyclohexanone and 9,10-phenanthrenequinone at high rates when compared with steroids, prostaglandins and sugars. The purified enzyme was inhibited by AgNO3, SH-reagent, disulfiram, hexesterol, stilbestrol, disulfiram and divalent cations such as Cu2+, Hg2+, Cd2+ and Co2+. Furthermore, the enzymatic properties of the purified enzyme, including catalytic activity, inhibitory effects by various agents and immunological properties, were compared with those of 3 alpha/beta-HSD enzymes from pig testicular cytosol.
Biol Pharm Bull 1994 Sep
PMID:Purification and characterization of 5 alpha-dihydrotestosterone 3 beta-hydroxysteroid dehydrogenase from mature pig testicular cytosol. 784 33

The synthesis of a 16 alpha-(bromoalkylamide) derivative of estradiol (N-butyl, N-methyl, 11-[3',17' beta-(dihydroxy)-1',3',5' (10')-estratrien-16' alpha-yl]-9(R/S)-bromo undecanamide) was performed by two different approaches starting from estrone. Each approach has the same key intermediate, containing an aldehyde group, but differs by the bromination step and the timing of formation of the amide group. This compound was found to cause, at 100 microM, a complete inhibition of 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) responsible for the interconversion of estrone and estradiol. The corresponding IC50 value was 10.6 microM. In the estrogen-sensitive ZR-75-1 human breast cancer cell line, this estradiol derivative has no estrogenic activity at 30 nM and only a minimal estrogenic activity (10% above the basal level) at 1 microM. At this latter concentration, this compound causes a 28% inhibition of 0.1 nM E2-induced cell proliferation (antiestrogenic activity). Thus, the introduction of a side-chain with a secondary bromide and a butyl methyl amide group at the 16 alpha-position of estradiol has two interesting effects; namely an inhibition of cytosolic 17 beta-HSD and a blockade of the estrogenic effect of estradiol.
Steroids 1994 Sep
PMID:N-butyl, N-methyl, 11-[3',17' beta-(dihydroxy)-1',3',5'(10')-estratrien-16' alpha-yl]-9(R/S)-bromo undecanamide: synthesis and 17 beta-HSD inhibiting, estrogenic and antiestrogenic activities. 784 36

Estrogenic 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) plays a pivotal role in the synthesis of estrogens. We overproduced human placental estrogenic 17 beta-HSD using a baculovirus expression system for the study of the enzyme mechanism. A cDNA encoding the entire open reading frame of human 17 beta-HSD was inserted into the genome of Autographa californica nuclear polyhedrosis virus and expressed in Spodoptera frugiperda (Sf9) insect cells. Metabolic labeling and Western blot analysis using polyclonal antibodies raised against native human 17 beta-HSD indicated that a molecule with an apparent mass of 35 kDa was maximally expressed 60 h after infection. At that time interval, intracellular 17 beta-HSD activity reached 0.26 U/mg of protein in crude homogenate, about 70 times the level measured in human placenta. Purification of recombinant 17 beta-HSD was achieved by a single affinity fast liquid protein chromatography step yielding 24 mg of purified 17 beta-HSD protein per liter of suspension culture, with a specific activity of about 8 mumol/min/mg of protein for conversion of estradiol into estrone, at pH 9.2. In addition, the recombinant protein purified from infected Sf9 cells was assembled as a dimer with molecular mass and specific activity identical to those of the enzyme purified directly from placenta. The present data show that the baculovirus expression system can provide active 17 beta-HSD that is functionally identical to its natural counter-part and easy to purify in quantities suitable for its physico-chemical studies.
J Steroid Biochem Mol Biol 1994 Sep
PMID:Human 17 beta-hydroxysteroid dehydrogenase: overproduction using a baculovirus expression system and characterization. 791 13

Seminiferous tubules prepared from adult rats cultured for 48 h in serum-free conditions produce multiple biological factors that modulate Leydig cell steroidogenic function in vitro. Using gel filtration chromatography, it was shown that seminiferous tubular culture medium (STCM) contained at least three inhibitory activities designated AI, AII, and AIII that inhibited testosterone production by purified Leydig cells. The factor that induced AIII activity, designated Leydig cell inhibitor (LCI), was further purified to apparent homogeneity by sequential HPLC using gel permeation, C8-, C18-, C2/C18-reversed-phase, and microbore anion exchange columns. When this batch of purified factor was resolved by SDS-PAGE under reducing conditions, only a single silver stained band with an apparent M(r) of 21,000 was detected. Protein sequence analysis using about 100 pmol of purified LCI revealed that its N-terminus was blocked. Incubation of this highly purified factor with Percoll gradient purified Leydig cells induced a dose-dependent inhibition of hCG-stimulated testosterone production. LCI inhibited the basal testosterone production and hCG-stimulated cAMP production by Leydig cell dose-dependently. It also inhibited the forskolin- and cholera toxin-stimulated testosterone and cAMP production but had no apparent effect on the binding of 125I-labeled hCG to LH receptors. These data suggest that this LCI exerts its inhibitory action at steps beyond the LH receptors but prior to the cAMP formation by affecting the adenylate cyclase activity directly or indirectly through inhibition of the stimulatory G-protein (Gs-protein); however, it is also possible that it decreases the coupling of the receptors to the Gs-protein. LCI also inhibited the conversion of exogenously added 22R-hydroxycholesterol, pregnenolone, progesterone, and 17 alpha-hydroxyprogesterone to testosterone. However, it had no effect on the conversion of dehydroepiandrostenedione and androstenedione to testosterone. These data strongly suggest that LCI affects the steroidogenic enzymes metabolizing cholesterol to testosterone, the cytochrome P-450 side-chain cleavage (P-450SCC), and cytochrome P-450 17 alpha-hydroxylase/17,20-lyase (P-450C17). However, it has no effect on the 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) enzyme activities. Based on the results of the present study, it is apparent that this LCI is distinct from other known potent Leydig cells inhibitors such as interleukin-1 (IL-1) and transforming growth factor-beta (TGF-beta). The LCI appears to involve in the paracrine regulation of Leydig cell function.
Mol Cell Endocrinol 1994 Sep
PMID:Rat seminiferous tubular culture medium contains a biological factor that inhibits Leydig cell steroidogenesis: its purification and mechanism of action. 798 48

The induction of Na,K-ATPase plays a vital role in mediating epithelial sodium transport. Although its activity is regulated by corticosteroids, it is uncertain whether this is predominantly by mineralo- or glucocorticoid mechanisms. 11 beta-Hydroxysteroid dehydrogenase (11 beta HSD) catalyzes the interconversion of active corticosterone (B) to inactive 11-dehydrocorticosterone and protects the nonselective mineralocorticoid receptor (MR) from glucocorticoid excess. We have studied the regulation of the alpha 1- and beta 1-subunits of Na,K-ATPase by mineralo- and glucocorticoids in vitro and in vivo, and how this is modulated by 11 beta HSD activity. Cultured rat kidney epithelial cells (NRK 52-E) expressed 11 beta HSD activity, which was inhibited by the licorice derivative glycyrrhetinic acid (GE). Dexamethasone, aldosterone, and high concentrations of B (1-10 microM) increased Na,K-ATPase alpha 1 and beta 1 messenger RNA (mRNA) levels, an effect that was inhibited by coincubation with the MR antagonist RU 26752, but not by the glucocorticoid receptor antagonist RU 38486. GE, which itself reduced Na,K-ATPase alpha 1/beta 1 mRNA levels, potentiated the action of B, so that low concentrations of B (10 nM) increased Na,K-ATPase alpha 1/beta 1 mRNA levels. In contrast, in vivo, RU 26752 and RU 38486 given ip for 4 days (n = 6/group) reduced renal Na,K-ATPase alpha 1 and beta 1 levels. Glycyrrhizic acid also inhibited both renal 11 beta HSD mRNA and activity and levels of Na,K-ATPase alpha 1/beta 1 mRNA. In vivo renal Na,K-ATPase subunit mRNA levels are regulated by both mineralo- and glucocorticoid mechanisms. In vitro, however, although NRK 52-E cells expressed the glucocorticoid receptor, corticosteroid regulation of Na,K-ATPase, even by dexamethasone, occurred exclusively via the MR, suggesting that accessory transcription factors required for glucocorticoid hormone action are absent in this cell line. Finally, although the licorice derivatives GE and glycyrrhizic acid reduced Na,K-ATPase alpha 1/beta 1 mRNA levels, they also potentiated the stimulatory effect of B by inhibiting its metabolism via 11 beta HSD, establishing 11 beta HSD as an important prereceptor modulator of mineralocorticoid hormone action.
Endocrinology 1994 Sep
PMID:Regulation of sodium-potassium adenosine triphosphate subunit gene expression by corticosteroids and 11 beta-hydroxysteroid dehydrogenase activity. 807 Mar 85

Cortisol is converted to the inactive glucocorticoid, cortisone, in several tissues by 11 beta-hydroxysteroid dehydrogenase (11 beta HSD). We have recently measured 11 beta HSD activity in cultured human granulosa-lutein cells recovered from patients undergoing in-vitro fertilisation and embryo transfer (IVF-ET). We now report an association between the outcome of IVF-ET and 11 beta HSD activity in these cells. Of the 64 patients studied, 32 had detectable 11 beta HSD activity and none became pregnant; whereas 76% of the remaining "11 beta HSD-negative" patients achieved pregnancies. Hence 11 beta HSD activity may predict the outcome of IVF-ET.
Lancet 1993 Sep 18
PMID:Ovarian 11 beta-hydroxysteroid dehydrogenase: potential predictor of conception by in-vitro fertilisation and embryo transfer. 810 24

The sexually dimorphic pattern of GH secretion regulates the expression of several steroidogenic enzymes in rat liver, including a male-specific 3 beta-hydroxysteroid dehydrogenase/delta 5-->4-isomerase (3 beta HSD). Recently, we identified male-specific isoforms of immunoreactive 3 beta HSD in mouse liver [42 kilodaltons (kDa)] and gonads (47 kDa). To test whether GH can regulate the expression of these murine 3 beta HSDs, endogenous forms of 3 beta HSD were studied in transgenic mice expressing heterologous GH transgene products. Mice from five transgenic lines were used; two expressed GH transgenes encoding the phosphoenolpyruvate carboxykinase (PEPCK) promoter fused to either the human (h) GH (somatogenic and lactogenic) or bovine (b) GH (somatogenic) structural genes, and three expressed GH transgenes encoding the mouse metallothionein-1 (MT1) promoter fused to the hGH, hGH variant (hGHv), or bGH structural genes. Control mice were normal nontransgenic littermates. Expression of a male-specific (42 kDa) isoform of hepatic 3 beta HSD is dramatically suppressed in all transgenic mouse lines, as detected on Western immunoblots, without affecting a 47-kDa isoform expressed in livers of both male and female mice. This negative regulation was not observed in mouse kidney, which normally expresses two 3 beta HSD isoforms (in both sexes) with molecular masses similar to those in liver. Considering that PEPCK and MT1 promoters direct expression of GH fusion genes in both tissues, the inhibition of hepatic, but not renal, 3 beta HSD immunoreactivity suggests that GH affects sex-specific, rather than tissue-specific, expression of 3 beta HSD. As in the liver, sex-specific expression of 3 beta HSD in the testis is also suppressed by heterologous GH, but with one notable difference. Only human-derived GH (MT1-hGH and MT1-hGHv) effectively inhibits expression of the 47-kDa sex-specific isoform of testicular 3 beta HSD, without affecting the 44-kDa isoform expressed in gonads of both male and female mice. These results suggest that the negative effects of heterologous GH on sex-specific 3 beta HSDs may be mediated by PRL receptors in the testis and GH receptors in the liver. PEPCK-GH transgenes had little effect on testicular 3 beta HSD, possibly because this promoter (unlike MT1) is relatively inactive in this tissue. In the liver of male transgenics (PEPCK-hGH), loss of the sex-specific (42-kDa) 3 beta HSD has little effect on the Km for dehydroepiandrosterone (DHEA; 11 microM) compared with that in normal controls (16 microM).(ABSTRACT TRUNCATED AT 400 WORDS)
Endocrinology 1993 Sep
PMID:Growth hormone transgenes regulate the expression of sex-specific isoforms of 3 beta-hydroxysteroid dehydrogenase/delta 5-->4-isomerase in mouse liver and gonads. 836 57

We examined the regulation of steroid production in fetal zone cells from midgestation (16-21 weeks) human fetal adrenal glands to elucidate the mechanism by which these cells secrete large quantities of dehydroepiandrosterone sulfate (DHAS) and little cortisol in response to ACTH. Our underlying hypothesis is that estrogen and insulin-like to ACTH. Our underlying hypothesis is that estrogen and insulin-like growth factor-II (IGF-II) modulate the steroidogenic response of fetal zone cells to ACTH, driving steroid production toward DHAS rather than cortisol. We also hypothesize that the effects of IGF-II and estrogen on steroidogenesis are achieved by modulating the expression of key enzymes in the steroidogenic pathway. Basal cortisol secretion by cultured fetal zone cells was below the limit of assay sensitivity (< 0.54 pmol/10(5) cells.24 h), whereas basal DHAS secretion was 210.8 +/- 41.0 pmol/10(5) cells.24 h (mean +/- SE). ACTH-(1-24) increased the secretion of cortisol to 228.96 +/- 6.75 pmol/10(5) cells.24 h and that of DHAS to 2039.8 +/- 121.7 pmol/10(5) cells.24 h. Neither IGF-II nor estradiol (E2) affected basal (no added ACTH) steroid secretion by fetal zone cells. IGF-II increased ACTH-stimulated cortisol and DHAS secretion by fetal zone cells in a dose-dependent fashion. In contrast, E2 at high concentrations (1-10 mumol/L) decreased ACTH-stimulated cortisol production to basal levels, but increased ACTH-stimulated DHAS production 1.5- to 2-fold. Combinations of IGF-II (100 ng/mL) and E2 (1 mumol/L) increased ACTH-stimulated cortisol and DHAS secretion by 1.5- to 2-fold compared with control values. However, compared with cultures exposed to IGF-II alone, inclusion of E2 decreased ACTH-stimulated cortisol secretion by about 60% and increased ACTH-stimulated DHAS secretion by about 50%. IGF-II increased the abundance of ACTH-stimulated mRNAs encoding cholesterol side-chain cleavage cytochrome P450 (P450scc), 17 alpha hydroxylase/17,20 lyase P450 (P450c17), and 3 beta-hydroxysteroid dehydrogenase (3 beta HSD). In addition, IGF-II increased the abundance of mRNA encoding P450c17 under basal conditions, but did not affect the basal expression of P450scc or 3 beta HSD. E2 had no effect on basal expression of these steroidogenic enzymes, but increased the abundance of ACTH-stimulated mRNA encoding P450scc and P450c17. The abundance of mRNA encoding 3 beta HSD was not affected by E2. The effect of IGF-II and E2 in combination on steroidogenic enzyme mRNA abundance was not different from that of IGF-II alone. These data indicate that IGF-II increases ACTH-stimulated steroid production in fetal zone cells by increasing the expression of key steroidogenic enzymes.(ABSTRACT TRUNCATED AT 400 WORDS)
J Clin Endocrinol Metab 1993 Sep
PMID:Interaction of insulin-like growth factor-II and estradiol directs steroidogenesis in the human fetal adrenal toward dehydroepiandrosterone sulfate production. 839 78

11 beta-Hydroxysteroid dehydrogenase (11 beta HSD) converts glucocorticoids to inactive products and is thus thought to confer specificity for aldosterone on the type I mineralocorticoid receptor in the kidney. Recent studies indicate the presence of at least two isozymes of 11 beta HSD. In vitro, the NAD(+)-dependent kidney (type 2) isozyme catalyzes 11 beta-dehydrogenase but not reductase reactions, whereas the NADP(+)-dependent liver (type 1) isozyme catalyzes both reactions. We have now characterized the human gene encoding kidney 11 beta HSD (HSD11K). A bacteriophage P1 clone was isolated after screening a human genomic library by hybridization with sheep HSD11K cDNA. The gene consists of 5 exons spread over 6 kb. The nucleotide binding domain lies in the first and the second exon, and the catalytic domain in the fourth exon. The 5' flanking sequences and first exon are GC-rich (80%), suggesting that the gene may be transcriptionally regulated by factors that recognize GC-rich sequences. Fluorescence in situ hybridization of metaphase chromosomes with a positive P1 clone localized the gene to chromosome 16q22. In contrast, the HSD11L (liver isozyme) gene is located on chromosome 1 and contains 6 exons; the coding sequences of these genes are only 21% identical. HSD11K is expressed at high levels in the placenta and kidney of midgestation human fetuses and at lower levels in lung and testes. Different transcriptional start sites are utilized in kidney and placenta. These data should be applicable to genetic analysis of the syndrome of apparent mineralocorticoid excess, which may represent a deficiency of 11 beta HSD.
Genomics 1995 Sep 01
PMID:Gene structure and chromosomal localization of the human HSD11K gene encoding the kidney (type 2) isozyme of 11 beta-hydroxysteroid dehydrogenase. 853 71

11 beta-Hydroxysteroid dehydrogenase (11 beta-HSD) modulates the access of corticosteroids to their receptors and is important in blood pressure control. The excretion of renal 11 beta-HSD (ie, NAD(+)-dependent isoform) is thought to protect renal mineralocorticoid receptors from cortisol. To examine whether endogenous renal 11 beta-HSD inhibitory factor(s) may be involved in the pathophysiology of hypertension, we studied the urinary excretion of such inhibitors in 30 patients with low-renin essential hypertension and 20 normotensive control subjects. The effect of sodium restriction on the urinary excretion of the inhibitors wa also evaluated in six normotensive control subjects. Urine was extracted with Sep-Pak cartridges and high-performance liquid chromatography. Endogenous renal 11 beta-HSD inhibitors were measured by the inhibition of 11 beta-HSD bioactivity in microsomes from the human kidney. The urinary excretion of the inhibitors was significantly increased in patients with low-renin essential hypertension (1280 +/- 88 nmol/d, mean +/- SEM) compared with normotensive control subjects (704 +/- 56 nmol/d) (P < .05). Ratios of urinary tetrahydrocortisol+allo-tetrahydrocortisol to tetrahydrocortisone did not differ significantly. Sodium restriction reduced the urinary excretion of the endogenous renal 11 beta-HSD inhibitors but did not affect the ratio of urinary tetrahydrocortisol+allo-tetrahydrocortisol to tetrahydrocortisone. Endogenous renal 11 beta-HSD inhibitory factors may contribute to the pathogenesis of low-renin essential hypertension by modulating the activity of 11 beta-HSD. Sodium intake may directly or indirectly regulate the inhibitory factors.
 ...
PMID:Endogenous renal 11 beta-hydroxysteroid dehydrogenase inhibitory factors in patients with low-renin essential hypertension. 856 41


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