Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “20-Hydroxysteroid Dehydrogenases”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1979

Enzymes of steroid hormone metabolism in ovarian tissue of teleosts.

1. Substrate-velocity kinetics and some other characteristics of three enzymes involved in steroid hormone metabolism in the ovary of the common carp, Cyprinus carpio and of the grey mullet, Mugil cephalus were determined. 2. Labeled steroid products of the enzyme reactions were identified by thin-layer and gas-liquid chromatographies, as well as by formation of derivatives. 3. 5 alpha-Steroid reductase of carp ovary was found to have a Michaelis-Menten constant undistinguishable from that of rat ovarian tissue, while the Km of the enzyme in mullet ovarian tissue was found to be different. 4. The Km of 20 alpha-hydroxysteroid dehydrogenase of mullet ovarian tissue was similar to the value reported for mammalian gonadal tissue, but the constant for 17 beta-hydroxy-steroid dehydrogenase in the carp ovary was different. 5. It is for the first time that these enzymes of steroid hormone metabolism have been quantitatively determined in teleost ovarian tissue.

17-Hydroxysteroid Dehydrogenases↗
PubMed1979

"Affinity" chromatography of steroid-transforming enzymes with a non-steroidal ligand.

The chromatographic behaviour of an avian oestradiol-17 beta dehydrogenase, the 3(17) beta-hydroxy steroid dehydrogenase from Pseudomonas testosteroni and cortisone reductase from Streptomyces dehydrogenans was studied on columns of p-(phenoxypropoxy)aniline attached to CNBr-activated Sepharose. The ligand was effective in adsorbing the oestradiol dehydrogenase from a partially purified extract of chicken liver, and the cortisone reductase was perferentially retained when mixtures of the three dehydrogenases were applied to columns in 10mM-buffer. Under these conditions the 3(17)beta-hydroxy steroid dehydrogenase was eluted in the front, but was adsorbed in the presence of 3 M-KCl. beta-N-Acetylglucosaminidase present in the liver preparation was not retained by the ligand, whereas lactate dehydrogenase from rabbit muscle was adsorbed in a manner similar to the retention pattern found on affinity chromatography with 2',5'-ADP--Sepharose. The mean overall purification of the oestradiol dehydrogenase was 13-fold, with a mean recovery of 53%. p-(Phenoxypropoxy)aniline offers promise for the purification of steroid-transforming enzymes where elution with substrate or cofactor is not wanted. It is also suggested that the ligand may be of service in the purification of receptors of hormonal steroids.

17-Hydroxysteroid Dehydrogenases↗
PubMed1977

Enzyme histochemistry of cultured ovarian cells. III. Histochemical characteristics of bovine granulosa and theca interna cells grown separately in cell culture.

Granulosa and theca interna cells were isolated from bovine preovulatory ovarian follicles. They were cultured separately but in the same conditions of cell culture. Both cell types, grown as monolayers, were investigated histochemically with special regard to the activity of several hydroxysteroid dehydrogenases: delta53betaOH-SDH, 17betaOH-SDH, 20alphaOH-SDH and G6P-DH. Bovine granulosa and theca interna cells during in vitro culture showed high activity of delta53betaOH-SDH and G6P-DH, the enzymes essential to progesterone biosynthesis. Enzyme pattern of cultured cells indicated continuation in vitro of luteinization, which in the normal preovulatory follicle of the bovine ovary begins prior to ovulation. There was investigated as well the influence of single doses of gonadotrophic hormones and estradiol on growth, lipid contents and enzymic activity of cultured in vitro bovine granulosa and theca interna cells.

17-Hydroxysteroid Dehydrogenases↗
PubMed1976

Enzyme histochemistry of cultured ovarian cells. II. Histochemistry of porcine theca interna cells in tissue culture.

By means of histochemical technique the activities of delta53beta-, 17beta-, 20alpha-hydroxysteroid dehydrogenases and glucose-6-phosphate dehydrogenase, as well as alkaline and acid phosphatase were investigated in monolayer cultures of theca interna cells, isolated from preovulatory porcine ovarian follicles. It was found that theca interna cells exhibited high and constant activity of delta53beta-hydroxysteroid dehydrogenase and G6P-DH, whereas activities of both 17beta- and 20alpha-hydroxysteroid dehydrogenase were lower and showed some fluctuations during in vitro culture. Addition of LH to the medium brought about the increase of all studied dehydrogenases. FSH was less effective. Estradiol showed quite and inhibiting effect. All the hormones mentioned above caused the increase of alkaline and acid phosphatase activity in cultured porcine theca interna cells.

17-Hydroxysteroid Dehydrogenases↗
PubMed1979

Purine nucleoside triphosphates in Streptomyces hydrogenans. Influence of steroids on the relative nucleotide level.

Various steroids in the culture medium of Streptomyces hydrogenans cause a rapid decrease of the relative GTP content of the cells. The relative ATP level is significantly diminished in the presence of progesterone and testosterone acetate. The initial decrease of the relative GTP content is proportional to the growth inhibitory effect of the steroids tested. There is no relationship between steroid-dependent induction of the synthesis of 20 beta- and 17 beta-hydroxysteroid dehydrogenase and the ability of the steroids to decrease the relative GTP content of the cells.

17-Hydroxysteroid Dehydrogenases↗
PubMed1978

Steroid metabolism in normal mammary gland and in the dimethylbenzanthracene-induced mammary tumor of rats.

After incubation of [4-14C]progesterone with cell-free homogenates of 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced mammary tumor of rats, 20 alpha-hydroxy-4-pregnen-3-one, 5 alpha-pregnane-3,20-dione, 20 alpha-hydroxy-5 alpha-pregnan-3-one, 3 alpha-hydroxy-5 alpha-pregnan-20-one, and 5 alpha-pregnane-3 alpha, 20 alpha-diol were identified as the metabolites. In normal mammary tissue, however, 4-pregnene-3 alpha-diol was isolated in addition to 5 alpha-reduced, and 3 alpha- and 20 alpha-hydroxy metabolites. When radioactive testosterone was employed as a substrate, 5 alpha-dihydrotestosterone and 5 alpha-androstane-3 alpha, 17 beta-diol were obtained as the metabolites of the mammary tumor. In the normal mammary gland, only 4-andorstene 3 alpha, 17 beta-diol was formed as its metabolite. Although the enzyme activities relevant to the metabolism varied among the tumor examined, the activity of 20 alpha-hydroxysteroid dehydrogenase in the mammary tumor was significantly lower than that in the normal mammary gland, whereas the activity of 5 alpha-reductase was higher in some of the mammary tumors than in the normal gland. The 5 alpha-reductase activity in the normal mammary gland was mostly localized in the crude microsomal fraction, whereas the same enzyme activity in the tumor was detected in all the organelle fractions. The activities of 20 alpha-hydroxysteroid dehydrogenase and NADPH-linked 3 alpha-hydroxysteroid dehydrogenase were found mainly in the cytosol fractions of the tumor and the normal tissue. The NADH-linked 3 alpha-hydroxysteroid dehydrogenase activity was detected only in the cytosol fraction of the normal mammary gland, but in the tumor studied, the activity of this enzyme was detected in all the subcellular fractions examined.

20-Hydroxysteroid Dehydrogenases↗
PubMed1979

20 alpha-Hydroxysteroid oxidoreductase activity and 20 alpha-dihydroprogesterone concentration in human placenta before and after parturition.

The objective of this investigation was to determine if decreased biosynthesis or increased catabolism of progesterone (P) during labor was responsible for the decreased concentration of hormone observed in the human placenta after labor and vaginal delivery. No significant difference was found in P biosynthesis by placental tissues examined before and after labor as evidenced by a similar activity of 3 beta-hydroxysteroid dehydrogenase: delta 5-isomerase. In contrast, there was a marked increase in P catabolism during labor, as shown by a significant (p less than 0.05) change in placental 20 alpha-hydroxysteroid oxidoreductase activity which increased from 835.5 +/- 103 (mean +/- SEM) pmoles of 20 alpha-dihydroprogesterone (20 alpha-DHP) generated per milligram of protein per hour before labor to 1,160.4 +/- 101 pmoles/mg/hr after labor. A similar significant (p less than 0.02) increase in enzyme activity was noticed in parallel assays of the reverse (20 alpha-DHP leads to P) reaction. As a consequence of increased P catabolism, placentas after labor had a 20 alpha-DHP concentration of 63.7 +/- 9.5 (mean +/- SEM) ng/mg protein, a value which was significantly (p less than 0.05) larger than that found before labor (37.8 +/- 8.3 ng/mg protein). These changes resulted in a modification of the placental tissue P/20 alpha-DHP ratio which decreased from 2/1 before to 1/1 after labor. The results indicate that the catabolism of P to 20 alpha-DHP increases significantly during human parturition. This phenomenon may be of importance in the mechanism of initiation and continuation of labor.

20-Hydroxysteroid Dehydrogenases↗
PubMed2024

The AKR1C1-CYP1B1-cAMP signaling axis controls tumorigenicity and ferroptosis susceptibility of extrahepatic cholangiocarcinoma.

Extrahepatic cholangiocarcinoma (ECC), a highly malignant type of cancer with increasing incidence, has a poor prognosis due to limited treatment options. Based on genomic analysis of ECC patient samples, here we report that aldo-keto reductase family 1 member C1 (AKR1C1) is highly expressed in human ECC tissues and closely associated with ECC progression and poor prognosis. Intriguingly, we show that inducible AKR1C1 knockdown triggers ECC cells to undergo ferroptosis. Mechanistically, AKR1C1 degrades the protein stability of the cytochrome P450 family member CYP1B1, a newly discovered mediator of ferroptosis, via ubiquitin-proteasomal degradation. Additionally, AKR1C1 decreases CYP1B1 mRNA level through the transcriptional factor aryl-hydrocarbon receptor (AHR). Furthermore, the AKR1C1-CYP1B1 axis modulates ferroptosis in ECC cells via the cAMP-PKA signaling pathway. Finally, in a xenograft mouse model of ECC, AKR1C1 depletion sensitizes cancer cells to ferroptosis and synergizes with ferroptosis inducers to suppress tumor growth. Therefore, the AKR1C1-CYP1B1-cAMP signaling axis is a promising therapeutic target for ECC treatment, especially in combination with ferroptosis inducers.

Humans↗
PubMed1979

Effect of human chorionic gonadotropin and prolactin on 20 alpha-hydroxysteroid dehydrogenase activity in granulosa cells of immature rat ovary.

The effects of FSH, hCG, and PRL on the activity of 20 alpha-hydroxysteroid dehydrogenase (20 alpha-SDH) of separate ovarian components of hypophysectomized, diethylstilbestrol-treated rats were studied. Enzyme activity was found to reside mainly in granulosa cells. FSH induced an increase in enzyme activity. A preparation of FSH was purified by adsorbing its LH contamination on rat corpora lutea membranes and by further neutralizing LH traces with an antiserum to the beta-subunit of LH. This purified FSH retained the ability to induce a 6-fold increase in specific enzyme activity in granulosa cells of hypophysectomized, diethylstilbestrol-treated rats. Administration of hCG to rats treated with purified FSH, further enhanced 20 alpha-SDH activity in granulosa cells up to 11.5-fold above control. PRL, which is known to inhibit 20 alpha-SDH activity in regressing rat corpora lutea, suppressed the FSH-induced increase in enzyme activity in the granulosa cells.

20-Hydroxysteroid Dehydrogenases↗
PubMed1978

Initiation of human parturition. IX. Progesterone metabolism by placentas of early and late human gestation.

In in vitro studies it was found that, in the presence of added NADPH, the human placenta metabolizes progesterone to 20alpha-hydroxy-4-pregnen-3-one at increasing rates as pregnancy advances. A fivefold increase in 20alpha-hydroxysteroid oxidoreductase activity is observed in term placentas compared with the enzymic activity of placentas of 12 to 20 weeks' gestation (368 +/- 53 pmoles/mg protein/hr vs 71 +/- 8 pmoles/mg protein/hr). The 5alpha-reductase and 3beta-hydroxysteroid oxidoreductase activities were similar in placentas obtained from early and late human pregnancies.

20-Hydroxysteroid Dehydrogenases↗