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Smuc T, Pucelj MR, Sinkovec J, Husen B, Thole H, Lanisnik Rizner T. Expression analysis of the genes involved in estradiol and progesterone action in human ovarian endometriosis. Gynecol Endocrinol 2007; 23:105-11. [PMID: 17454161 DOI: 10.1080/09513590601152219] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Endometriosis is defined as the presence of endometrial glands and stroma within extrauterine sites, and it is well known that endometriosis is an estrogen-dependent disease. The defective formation and metabolism of steroid hormones is responsible for the promotion and development of endometriosis. In the present study we examined the mRNA levels of six enzymes that are involved in the metabolism of estrogen and progesterone--aromatase, 17beta-hydroxysteroid dehydrogenase (17beta-HSD) types 1, 2 and 7, sulfatase and sulfotransferase--and of the steroid receptors--estrogen receptors alpha and beta (ERalpha, ERbeta) and progesterone receptors A and B (PRAB)--implicated in human ovarian endometriosis. We analyzed 16 samples of ovarian endometriosis and 9 of normal endometrium. The real-time polymerase chain reaction analyses revealed that six of the nine genes investigated are differentially regulated. Aromatase, 17beta-HSD types 1 and 7, sulfatase and ERbeta were statistically significantly upregulated, while ERalpha was significantly downregulated, in the endometriosis group compared with the control group. There were no significant differences in 17beta-HSD type 2, sulfotransferase and PRAB gene expression. Our results indicate that, in addition to the previously reported upregulation of aromatase, upregulation of 17beta-HSD types 1 and 7 and sulfatase can also increase the local estradiol concentration. This could thus be responsible for the estrogen-dependent growth of endometriotic tissue. Surprisingly ERalpha was downregulated.
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Affiliation(s)
- Tina Smuc
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Vrasov trg. 2, 1000 Ljubljana, Slovenia
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Poirier D, Boivin RP, Tremblay MR, Bérubé M, Qiu W, Lin SX. Estradiol−Adenosine Hybrid Compounds Designed to Inhibit Type 1 17β-Hydroxysteroid Dehydrogenase. J Med Chem 2005; 48:8134-47. [PMID: 16366595 DOI: 10.1021/jm058235e] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The steroidogenic enzyme type 1 17beta-hydroxysteroid dehydrogenase (17beta-HSD) is involved in the synthesis of estradiol (E(2)), a hormone well-known to stimulate the growth of estrogen-sensitive tumors. To obtain compounds able to control E(2) formation, two moieties were linked with a methylene side chain: an adenosine moiety for interacting with the cofactor-binding site and an E(2) moiety for interacting with the substrate-binding site. When tested as inhibitors of type 1 17beta-HSD, the hybrid compounds inhibited the reductive activity (E(1) into E(2)) with IC(50) values ranging from 52 to 1,000 nM. The optimal side-chain length was determined to be eight methylene groups for a 16 beta-orientation. The presence of two components (E(2) and adenosine) is essential for good inhibition, since 16 beta-nonyl-E(2) and 5-nonanoyl-O-adenosine, two compounds having only one of the components, did not inhibit the enzyme. Moreover, the 3D-structure analysis of EM-1,745 complexed with type 1 17beta-HSD showed key interactions with both substrate- and cofactor-binding sites.
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Affiliation(s)
- Donald Poirier
- Oncology and Molecular Endocrinology Research Center, CHUQ-Pavillon CHUL and Université Laval, Québec G1V 4G2, Canada
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Qiu W, Campbell RL, Gangloff A, Dupuis P, Boivin RP, Tremblay MR, Poirier D, Lin SX. A concerted, rational design of type 1 17beta-hydroxysteroid dehydrogenase inhibitors: estradiol-adenosine hybrids with high affinity. FASEB J 2002; 16:1829-31. [PMID: 12223444 DOI: 10.1096/fj.02-0026fje] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Human estrogenic 17beta-hydroxysteroid dehydrogenase (17beta-HSD type 1) catalyzes the final step in the synthesis of active estrogens that stimulate the proliferation of breast cancer cells. Based on the initial premise to make use of the binding energies of both the substrate and cofactor sites, and molecular modeling starting from the enzyme structure, several estradiol-adenosine hybrids were designed and synthesized. Among these hybrids, EM-1745 with a linker of 8-CH2 groups is proved to be the best competitive inhibitor with a Ki of 3.0 +/- 0.8 nM. The crystal structure of the EM-1745 enzyme complex at 1.6 A provides evidence at atomic resolution of strong interactions between both the steroid and cofactor moieties and the enzyme molecule, as illustrated by a deltaA-weighted 2Fo-Fc electron density map contoured at 3.0 delta. The substrate entry loop is further stabilized in this complex compared with previous complexes of the enzyme. These results confirm our initial strategy of combining studies of structural biology and enzyme mechanism in the inhibitor design, which may be applied to other steroidogenic enzymes involved in human diseases.
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Affiliation(s)
- Wei Qiu
- Oncology and Molecular Endocrinology Research Center, Laval University Medical Center (CHUL) and Laval University, Quebec, G1V 4G2, Canada
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5
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Huang YW, Pineau I, Chang HJ, Azzi A, Bellemare V, Laberge S, Lin SX. Critical residues for the specificity of cofactors and substrates in human estrogenic 17beta-hydroxysteroid dehydrogenase 1: variants designed from the three-dimensional structure of the enzyme. Mol Endocrinol 2001; 15:2010-20. [PMID: 11682630 DOI: 10.1210/mend.15.11.0730] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Human estrogenic 17beta-hydroxysteroid dehydrogenase is an NADP(H)-preferring enzyme. It possesses 11- and 4-fold higher specificity toward NADP(H) over NAD(H) for oxidation and reduction, respectively, as demonstrated by kinetic studies. To elucidate the roles of the amino acids involved in cofactor specificity, we generated variants by site-directed mutagenesis. The results showed that introducing a positively charged residue, lysine, at the Ser12 position increased the enzyme's preference for NADP(H) more than 20-fold. Substitution of the negatively charged residue, aspartic acid, into the Leu36 position switched the enzyme's cofactor preference from NADPH to NAD with a 220-fold change in the ratio of the specificity toward the two cofactors in the case of oxidation. This variant dramatically abolished the enzyme's reductase function and stimulated its dehydrogenase activity, as shown by enzyme activity in intact cells. The substrate-binding pocket was also studied with four variants: Ser142Gly, Ser142Cys, His221Ala, and Glu282Ala. The Ser142Gly variant abolished most of the enzyme's oxidation and reduction activities. The residual reductase activity in vitro is less than 2% that of the wild-type enzyme. However, the Ser142Cys variant was fully inactive, both as a partially purified protein and in intact cells. This suggests that the bulky sulfhydryl group of cysteine entirely disrupted the catalytic triad and that the Ser142 side chain is important for maintaining the integrity of this triad. His221 variation weakened the apparent affinity for estrone, as demonstrated by a 30-fold increase in Michaelis-Menten constant, supporting its important role in substrate binding. This residue may play an important role in substrate inhibition via the formation of a dead-end complex. The formerly suggested importance of Glu282 could not be confirmed.
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Affiliation(s)
- Y W Huang
- Medical Research Council Group in Molecular Endocrinology, Oncology, and Molecular Endocrinology Research Center, Laval University Medical Center, Québec, Québec G1V 4G2, Canada
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6
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Poirier D, Dionne P, Auger S. A 6beta-(thiaheptanamide) derivative of estradiol as inhibitor of 17beta-hydroxysteroid dehydrogenase type 1. J Steroid Biochem Mol Biol 1998; 64:83-90. [PMID: 9569013 DOI: 10.1016/s0960-0760(97)00136-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In an effort to develop potent agents for reducing the levels of the active estrogen, estradiol, we developed a new category of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) type 1 inhibitors. The compounds described possess a butyl methyl alkylamide side chain linked to the C6 position of estradiol by a thioether. With a series of epimeric mixtures, an optimal side-chain length of five methylene groups (between the amide group and steroid part) was first determined. Thereafter, both C6 epimers of optimized mixture were obtained after high-pressure liquid chromatography separation. 1H and 13C NMR experiments were performed to confirm the stereochemistry of each epimer. The 6beta-orientation of the side-chain was found to be crucial for enzymatic inhibition. Indeed, for the optimized side-chain length, the compound with a beta-orientation (5: N-butyl,N-methyl 7-(3',17'beta-dihydroxy-1',3',5'( 10')-estratriene-6'beta-yl)-7-thiaheptanamide) was 70-fold more potent than the 6alpha-analog. Compound 5 did not inactivate 17beta-HSD type 1, suggesting a reversible inhibitor. In addition, it was found to be a more potent inhibitor than the substrate estrone itself or a panel of three known inhibitors.
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Affiliation(s)
- D Poirier
- Medicinal Chemistry Division, CHUL Research Center and Laval University, Quebec, Canada.
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Affiliation(s)
- T M Penning
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia 19104-6084, USA
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8
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Azzi A, Rehse PH, Zhu DW, Campbell RL, Labrie F, Lin SX. Crystal structure of human estrogenic 17 beta-hydroxysteroid dehydrogenase complexed with 17 beta-estradiol. NATURE STRUCTURAL BIOLOGY 1996; 3:665-8. [PMID: 8756321 DOI: 10.1038/nsb0896-665] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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9
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Deyashiki Y, Ohshima K, Nakanishi M, Sato K, Matsuura K, Hara A. Molecular cloning and characterization of mouse estradiol 17 beta-dehydrogenase (A-specific), a member of the aldoketoreductase family. J Biol Chem 1995; 270:10461-7. [PMID: 7737980 DOI: 10.1074/jbc.270.18.10461] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Several mammalian livers contain monomeric 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) with A-stereospecificity in hydrogen transfer, which differs from the B-specific dimeric enzyme of human placenta in its ability to catalyze the oxidoreduction of xenobiotic trans-dihydrodiols of aromatic hydrocarbons and carbonyl compounds. Here, we report the isolation and characterization of a mouse cDNA clone encoding monomeric 17 beta-HSD of the liver. This clone had an entire coding region for a protein of 323 amino acid residues with a molecular weight of 37,055. The deduced sequence of the protein aligned with a high degree of identity with rat and rabbit 20 alpha-HSDs, rat and human 3 alpha-HSD/dihydrodiol dehydrogenases, and bovine prostaglandin F synthase, which are members of the aldoketoreductase family, but was distinct from human 17 beta-HSD and carbonyl reductase, members of the short chain dehydrogenases. The expression of the cDNA in Escherichia coli resulted in synthesis of a protein that was active toward androgens, estrogens, and xenobiotic substrates. The recombinant and mouse liver 17 beta-HSDs also exhibited low 20 alpha-HSD activity toward progestins, which is similar to bifunctional activity of human placental 17 beta-HSD. Therefore, the mouse enzyme was given the designation of estradiol 17 beta-dehydrogenase (A-specific). Northern analysis of mouse tissues revealed the existence of a single 1.7-kilobase 17 beta-HSD mRNA species in the liver, kidney, testis, and stomach. The liver mRNA content was considerably more abundant than those found in the other tissues, as 17 beta-HSD protein was mainly detected in the liver by Western analysis.
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Affiliation(s)
- Y Deyashiki
- Biochemistry Laboratory, Gifu Pharmaceutical University, Japan
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10
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Breton R, Yang F, Jin JZ, Li B, Labrie F, Lin SX. Human 17 beta-hydroxysteroid dehydrogenase: overproduction using a baculovirus expression system and characterization. J Steroid Biochem Mol Biol 1994; 50:275-82. [PMID: 7918113 DOI: 10.1016/0960-0760(94)90132-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
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.
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Affiliation(s)
- R Breton
- MRC Group in Molecular Endocrinology, CHUL Research Center, Quebec, Canada
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11
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De La Llosa-Hermier MP, Nocart M, Paly J, Hermier C. 20-alpha-Hydroxysteroid dehydrogenase from pseudopregnant rat ovary: obtention and characterization of a monoclonal antibody against the enzyme activity. Biochimie 1992; 74:1117-20. [PMID: 1292619 DOI: 10.1016/0300-9084(92)90010-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The enzyme 20-alpha-hydroxysteroid dehydrogenase (20-alpha-HSD) was purified from pseudopregnant rat ovaries and used as antigen for the development of a monoclonal antibody by the hybridoma technique. Spleen cells of BALB/c mice immunized with purified 20-alpha-HSD were fused with SP2/0 mouse myeloma cells. Among the colonies of hybrid cells, one (designated mAb-HSD 11) was found to be secreting antibodies (IgM) able to inhibit 20-alpha-HSD activity. The antibody-secreting hybridome was amplified by ascitic fluid production and the monoclonal antibody purified by Bakerbond ABx procedure. Purified mAb-HSD 11 was able to inhibit 20-alpha-HSD activity in a dose-dependent manner. Studies of Michaelis constants of 20-alpha-HSD indicate that this monoclonal antibody increases the Km for 20-alpha-dihydroprogesterone and decreases the Vmax.
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12
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Lin S, Yang F, Jin J, Breton R, Zhu D, Luu-The V, Labrie F. Subunit identity of the dimeric 17 beta-hydroxysteroid dehydrogenase from human placenta. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)41984-9] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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13
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Penning TM, Thronton R, Ricigliano JW. Clues to the development of mechanism-based inactivators of 3 alpha-hydroxysteroid dehydrogenase: comparison of steroidal and nonsteroidal Michael acceptors and epoxides. Steroids 1991; 56:420-7. [PMID: 1788860 DOI: 10.1016/0039-128x(91)90030-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A series of steroidal and nonsteroidal Michael acceptors that represent reaction products for 3 alpha-hydroxysteroid dehydrogenase were synthesized and evaluated as potential enzyme-generated inactivators. Introduction of exocyclic olefins either at C-2 or C-6 produced inhibitors with high affinity for the enzyme (0.05 to 5.0 microM). However, despite this affinity, none of these compounds produced time-dependent inactivation of the enzyme. By contrast, analogs based on 1-phenyl-2-propen-1-one were stoichiometric inactivators of the enzyme and ease of turnover of the parent latent Michael acceptor depended on the presence of an electron-withdrawing substituent at the para position. A series of steroidal and nonsteroidal epoxides in which the oxiranyl oxygen could be substituted for the 3-ketone (the acceptor carbonyl of a steroid substrate) were also synthesized and evaluated as potential mechanism-based inactivators. Steroidal 2 alpha,3 alpha-, and 3 alpha,4 alpha-epoxides as well as 3 alpha- and 3 beta-spiroepoxides did not bind to the enzyme and were unable to cause enzyme inactivation in either the presence or absence of pyridine nucleotide. In contrast, nitrostyrene oxides produced time-dependent inactivation, the rate of which was governed by the presence of an electron withdrawing group at the para position. These data indicate that the design of mechanism-based inactivators for 3 alpha-hydroxysteroid dehydrogenase requires the incorporation of electron-withdrawing groups adjacent to the latent enzyme-activated group and, as a result, the turnover and/or reactivity of these compounds is increased. Moreover, these compounds can be modeled on nonsteroids.
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Affiliation(s)
- T M Penning
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia 19104-6084
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Penning TM, Ricigliano JW. Mechanism based inhibition of hydroxysteroid dehydrogenases. JOURNAL OF ENZYME INHIBITION 1991; 5:165-98. [PMID: 1669446 DOI: 10.3109/14756369109080057] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Steroid hormone action can be regulated not only at the receptor level but also by the enzymes that are responsible for the synthesis and degradation of biologically active steroids. Traditionally the pharmacological intervention of steroid hormone action has focused on the development of steroidal and nonsteroidal hormone receptor agonists and antagonists with appropriate pharmacokinetics. Recently, the development of selective inhibitors/inactivators of steroid metabolizing enzymes has gained momentum. This review will concentrate on the development of mechanism-based inhibitors for one class of steroid hormone transforming enzymes, the hydroxysteroid dehydrogenases.
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Affiliation(s)
- T M Penning
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia 19104-6084
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Auchus RJ, Palmer JO, Carrell HL, Covey DF. Preparation of 14,15-secoestra-1,3,5(10)-trien-15-ynes, inhibitors of estradiol dehydrogenase. Steroids 1989; 53:77-96. [PMID: 2772972 DOI: 10.1016/0039-128x(89)90147-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The conversion of estrone to 14,15-secoestratrien-15-ynes, inactivators of estradiol dehydrogenase from human term placenta, is described. The optically pure precursor 7-acetoxy-octahydro-2-phenanthrenecarboxylic acid methyl ester is prepared from estrone in five steps and 40% yield. The unsubstituted propargylic secoestratriene diol, a mechanism-based inactivator of estradiol dehydrogenase, and the corresponding acetylenic ketone, an affinity label inactivator of the same enzyme, arise from the phenanthrene ester in three and four steps. The propargylic secoestratriene diol also competes with [3H]estradiol for binding to calf uterus estrogen receptor and possesses weak uterotrophic activity.
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Affiliation(s)
- R J Auchus
- Department of Pharmacology, Washington University School of Medicine, St. Louis, MO 63110
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Thomas JL, Asibey-Berko E, Strickler RC. The affinity alkylators, 11 alpha-bromoacetoxyprogesterone and estrone 3-bromoacetate, modify a common histidyl residue in the active site of human placental 17 beta,20 alpha-hydroxysteroid dehydrogenase. JOURNAL OF STEROID BIOCHEMISTRY 1986; 25:103-8. [PMID: 3462434 DOI: 10.1016/0022-4731(86)90287-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Purified human placental 17 beta,20 alpha-hydroxysteroid dehydrogenase (native enzyme) was completely inactivated by the affinity alkylator, estrone 3-bromoacetate, in the presence of cofactor (NADPH). The inactivated enzyme was reactivated to 100% activity by base-catalyzed hydrolysis of the steroidal ester-enzyme conjugate and then repurified by dialysis. Control enzyme in mixtures which contained estrone in place of alkylator was treated the same as the reactivated enzyme. 11 alpha-Bromo[2'-14C]acetoxyprogesterone, an active site-directed affinity alkylator of the enzyme, produced 5.0-fold less radiolabeled 3-(carboxymethyl)histidine and S-(carboxymethyl)cysteine plus 1.4-fold more 1,3-bis(carboxymethyl)-histidine in the reactivated enzyme than in the control enzyme. The lesser amount of S-(carboxymethyl)cysteine and greater amount of 1,3-bis(carboxymethyl)histidine resulted from nonspecific interactions between the reactivated enzyme and the progestin radioalkylator. The nonradiolabeled 3-(carboxymethyl)histidine originally produced by estrone 3-bromoacetate in the enzyme active site hindered radioalkylation of this amino acid by 11 alpha-bromo[2'-14C]acetoxyprogesterone to yield 5-fold less radiolabeled 3-(carboxymethyl)histidine in the reactivated enzyme relative to control enzyme. Thus, the estrogen and progestin affinity alkylators modified a common histidyl residue in the active site. These studies are direct evidence that the estradiol 17 beta-dehydrogenase and 20 alpha-hydroxysteroid dehydrogenase activities reside at a common locus on a single protein.
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17
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Thomas JL, LaRochelle MC, Asibey-Berko E, Strickler RC. Reactivation of human placental 17 beta,20 alpha-hydroxysteroid dehydrogenase affinity alkylated by estrone 3-(bromoacetate): topographic studies with 16 alpha-(bromoacetoxy)estradiol 3-(methyl ether). Biochemistry 1985; 24:5361-7. [PMID: 3865689 DOI: 10.1021/bi00341a014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Estradiol 17 beta-dehydrogenase and 20 alpha-hydroxysteroid dehydrogenase, oxidoreductase activities copurified from the cytosol of human-term placenta as a homogeneous protein (native enzyme), were reactivated at equal rates to 100% activity following complete inactivation in the presence of cofactor (NADPH) with the affinity alkylator estrone 3-(bromoacetate). Reactivation was accomplished by base-catalyzed hydrolysis of steroidal ester-amino acid linkages in the enzyme active site. The rate of enzyme reactivation was pH dependent. In identical studies without NADPH, only 12% of the original enzyme activity was restored. Completely reactivated enzyme was repurified by dialysis. Enzyme in control mixtures (control enzyme) that contained estrone in place of alkylator was treated the same as the reactivated enzyme. Reactivated enzyme exhibited a 6.0-fold lower affinity for common substrates, a 1.8-fold lesser affinity for NAD+ and NADH, and the same affinity for NADP+ and NADPH compared to control enzyme. In incubations that included NADPH, the reactivated enzyme maintained full activity during a 20-h second exposure to estrone 3-(bromoacetate), but in identical incubations without NADPH, the reactivated enzyme was rapidly inactivated at the same rate as the control and native enzymes. The control and reactivated enzymes were inactivated at equal rates by 16 alpha-(bromoacetoxy)estradiol 3-(methyl ether) in the presence or absence of cofactor (NADP+) and exhibited similar Kitz and Wilson inhibition constants for this affinity alkylator. Estrone 3-(bromo[2'-14C]acetate) incubated with native enzyme and NADPH produced radiolabeled 3-(carboxymethyl)histidine and S-(carboxymethyl)cysteine.(ABSTRACT TRUNCATED AT 250 WORDS)
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18
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Mendoza-Hernández G, Calcagno M, Sánchez-Nuncio HR, Díaz-Zagoya JC. Dehydroepiandrosterone is a substrate for estradiol 17 beta-dehydrogenase from human placenta. Biochem Biophys Res Commun 1984; 119:83-7. [PMID: 6231029 DOI: 10.1016/0006-291x(84)91621-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The enzyme estradiol 17 beta-dehydrogenase (17 beta-ED) [E.C.1.1.1.62] from human placenta was purified to homogeneity by the initial steps of a published procedure, followed by an affinity chromatography step in Reactive Blue 2-Sepharose, eluting with NADP. The pure enzyme is not specific for estrogenic substrates, it also catalyzes the oxidation-reduction of several androgens and progesterone (i.e. dehydroepiandrosterone, androstenedione, 5 alpha-dihydrotestosterone, and 20 alpha-dihydroprogesterone). The comparison of the kinetic parameters for these substrates, shows that dehydroepiandrosterone could be a physiological ligand of the enzyme, and consequently involved in the control of its function in estrogen metabolism.
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19
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LaRochelle MC, Thomas JL, Strickler RC. Reactivation of human placental 17 beta, 20 alpha-hydroxysteroid dehydrogenase: affirmation of affinity labeling principles. Steroids 1984; 43:209-17. [PMID: 6596780 DOI: 10.1016/0039-128x(84)90039-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Human placental 17 beta, 20 alpha-hydroxysteroid dehydrogenase was completely inactivated by the affinity alkylator, 3-bromoacetoxy-1,3,5(10)-estratrien-17-one (estrone 3-bromoacetate). The inactivated enzyme was then reactivated to 100% of the enzyme activity by base-catalyzed hydrolysis of the steroidalester-enzyme conjugate. After the reactivated enzyme was repurified by dialysis, re-inactivation studies were performed on it. The reactivated enzyme could not be re-inactivated by the original alkylator, estrone 3-bromoacetate. However, 16 alpha-bromoacetoxyestradiol-17 beta 3-methyl ether caused a loss of reactivated enzyme activity at a rate comparable to that for the native enzyme. These observations demonstrate that a specific amino acid modification within the enzyme active site was produced by estrone 3-bromoacetate alkylation and suggest that the conformation of the active center was essentially unaltered. Thus, these successful reactivation studies of 17 beta, 20 alpha-hydroxysteroid dehydrogenase affirm the specificity of affinity labeling. This methodology also offers a new tool to investigate the steroid binding regions of macromolecular proteins.
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20
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Katzenellenbogen JA, Katzenellenbogen BS. Affinity labeling of receptors for steroid and thyroid hormones. VITAMINS AND HORMONES 1984; 41:213-74. [PMID: 6099632 DOI: 10.1016/s0083-6729(08)60091-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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21
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Thomas JL, LaRochelle MC, Covey DF, Strickler RC. Inactivation of human placental 17 beta,20 alpha-hydroxysteroid dehydrogenase by 16-methylene estrone, an affinity alkylator enzymatically generated from 16-methylene estradiol-17 beta. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(17)44255-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Thomas JL, Strickler RC. Human placental 17 beta-estradiol dehydrogenase and 20 alpha-hydroxysteroid dehydrogenase. Studies with 6 beta-bromoacetoxyprogesterone. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(18)33024-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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