Journal of steroid biochemistry最新文献

{"title":"Uterine estrogen sulfatase activity. Influence of steroid hormones and adenine nucleotides","authors":"MariáCristina Loza ,&nbsp;Antonio Valencia ,&nbsp;Juan José Hicks","doi":"10.1016/0022-4731(90)90221-D","DOIUrl":"10.1016/0022-4731(90)90221-D","url":null,"abstract":"<div><p>Steroid sulfatase enzymes participate greatly in reproductive events. To date, estrogen sulfatase seems to have a regulatory role in the control of free estrogen levels in target tissues.</p><p>The present study evaluates the participation of some adenine nucleotides in estrogen sulfatase kinetics. Using ADP, ATP, NAD and the combination of ADP + NAD or ATP + NAD it was found that adding either of the combined cofactors, the enzymatic activity increased more than 2.0 times.</p><p>In ovariectomized rats, the corresponding mean enzyme activity was found to be higher than in intact rats. It was also found, in ovariectomi/ed rats treated with ovarian hormones, an inhibition that was higher with estradiol-17β than with progesterone treatment.</p><p>This data suggests that the estrogen sulfatase, being a hormone-dependent enzyme, participates in a new control mechanism of estrogen levels in presence of some cofactors and free steroids.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Pages 301-303"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90221-D","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13540123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of new steroid haptens for radioimmunoassay—VIII. Development and validation of a specific radioimmunoassay for serum 5α-androstane-3α,17β-diol 17-glucuronide","authors":"David L. Thompson ,&nbsp;Roger S. Rittmaster ,&nbsp;Angela M. Rodriguez ,&nbsp;Perry H. Moore Jr ,&nbsp;Pemmaraju N. Rao","doi":"10.1016/0022-4731(90)90227-J","DOIUrl":"10.1016/0022-4731(90)90227-J","url":null,"abstract":"<div><p>5α-Androstane-3α,17β-diol glucuronide (androstanediol-G) is a dihydrotestosterone metabolite whose serum levels are elevated in hirsute women. Current assay methods do not distinguish between the two androstanediol-G isomers, androstanediol 3-G and androstanediol 17-G. Since the production of these isomers may be influenced by different factors, we have developed a specific radioimmunoassay for androstanediol 17G. The antibody was raised against 5α-androstane-3α,17β-diol 17-G conjugated to bovine serum albumin (BSA). [9,11-³H]5α-Androstane-3α,17β-diol 17-G was used for determination of procedural losses and as the labeled ligand in the assay. Unlabeled androstanediol 17-G was used as assay standard.</p><p>Serum levels of total androstanediol-G, androstanediol 3-G and androstanediol 17-G were measured in 8 normal men. Total androstanediol-G levels were 16.5 ± 5.2 nmol/l, androstanediol 17-G levels were 12.9 ± 5 nmol/l, and androstanediol 3-G levels were 30.3 ± 1.8 nmol/l. 77 ± 13% of total androstanediol-G was androstanediol 17-G.</p><p>These results confirm our previous findings that androstanediol 17-G is the predominant androstanediol-G isomer in human serum and suggests that 5α-dihydrotestosterone (DHT) is preferentially metabolized to androstanediol 17-G.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Pages 345-349"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90227-J","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13538534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Testosterone micromilieu in staged rat seminiferous tubules","authors":"Martti Parvinen,&nbsp;Ilpo Huhtaniemi","doi":"10.1016/0022-4731(90)90232-H","DOIUrl":"10.1016/0022-4731(90)90232-H","url":null,"abstract":"<div><p>Endogenous testosterone concentrations in rat seminiferous tubules were measured in relation to different stages of the cycle of the seminiferous epithelium. For this purpose, the seminiferous tubules were mechanically separated from the interstitial tissue on a cooled (1°C) petri dish under a stereomicroscope without added medium. After recognition of the stages of the cycle by transillumination, the specimens were rapidly transferred by dry forceps into test tubes for testosterone radioimmunoassay. The results of the dry dissection method were compared with measurements on tubules that were kept after separation in phosphate buffered saline (PBS, pH 7.4), in order to reveal the possible leakage of testosterone from the tubules. The maximal concentration of testosterone per unit length of seminiferous tubule was found in stages VII and VIII of the cycle (288 ± 60 fmol/cm, mean ± SEM, <em>n</em> = 12), and the minimal in stages IX–XII (219 ± 57 fmol/cm, <em>P</em> &lt; 0.01). If the levels were correlated with unit volumes of the seminiferous tubules, identical concentrations of testosterone (521–542 fmol/mm³, approx. 500 nmol/l) were found in the different stages of the cycle. Despite the similarity of testosterone concentrations in the different parts of the seminiferous tubules the local concentrations of biologically active (i.e. free) testosterone may be modulated by extracellular and intracellular androgen binding components.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Pages 377-381"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90232-H","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13538539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modified acetylenic steroids as potent mechanism-based inhibitors of cytochrome P-450SCC","authors":"O. Olakanmi,&nbsp;D.W. Seybert","doi":"10.1016/0022-4731(90)90217-G","DOIUrl":"10.1016/0022-4731(90)90217-G","url":null,"abstract":"<div><p>Synthesized 20-(4-tetrahydropyranyl-1-butynyloxy)-5-pregnen-3α,20β-diol [steroid I] and 20-(3-tetrahydropyranyl-1-propargyloxy)-5-pregnen-3α,20β-diol [steroid III] have been found to inactivate purified adrenocortical cytochrome <em>P</em>-450_SCC. When incubated with the enzyme under turnover conditions, steroid I inactivated cytochrome <em>P</em>-450_SCC by about 85% in 40 min. This is in contrast to the free triol analog, steroid II which inactivated the enzyme by only 45% within the same incubation period. A comparison of steroid III with its free triol analog, steroid IV, also showed that the diol is a more effective inactivator of the enzyme than the triol. The partition ratio was calculated by two different methods. Each of the steroids I–IV bound to the enzyme with spectrophotometric dissociation constant (<em>K</em>_<em>s</em>) in the micromolar range, producing Type II low spin spectra changes during titration of the enzyme. In addition, it was found that the binding of each of the compounds to the enzyme occurred without inactivation of the enzyme and that the inactivation under turnover condition, is not as a result of conversion to the denatured <em>P</em>-420 species. This demonstrated that steroids I and III could correctly be designated as mechanism-based (suicide) inhibitors. The kinetic studies demonstrated that steroids with the tetrahydropyranyl substituent are more potent inhibitors of cytochrome <em>P</em>-450_SCC as shown by an initial turnover rate of 0.06 min⁻¹, an inactivation rate constant of 0.05 min⁻¹, and a partition ratio of about 1.0 for steroid I. Based on our finding, possible mechanisms of inactivation of cytochrome <em>P</em>-450_SCC by these acetylenic steroids are propsoed.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Pages 273-280"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90217-G","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13540120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fourth international congress on hormones and cancer","authors":"","doi":"10.1016/0022-4731(90)90240-S","DOIUrl":"https://doi.org/10.1016/0022-4731(90)90240-S","url":null,"abstract":"","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Page III"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90240-S","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136498336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estrogen-binding properties of rat serum α1-fetoprotein and its isoforms. Investigation of the apparent non-integrality of sites on the unfractionated protein","authors":"Françoise Hérve ,&nbsp;Myriam Gentin ,&nbsp;Krzysztof M. Rajkowski ,&nbsp;Lawrence T. Wong ,&nbsp;Carleton J.C. Hsia ,&nbsp;Nicole Cittanova","doi":"10.1016/0022-4731(90)90224-G","DOIUrl":"10.1016/0022-4731(90)90224-G","url":null,"abstract":"<div><p>Rat fetal serum α₁-fetoprotein (AFP), a heterogeneous glycoprotein, binds estrogens with high affinity but at a fractional number of sites even after treatment with charcoal (<em>n</em> = 0.6), which may mean 60% of the protein has 1 site and the remainder none. To investigate the origin of this fractional number of sites the “native” protein (purified by negative affinity chromatography) was further purified (step 1) and fractionated (step 2) into its two main charge variants (electrophoretically “slow” and “fast”) by a two-step fast-protein liquid chromatography method. The binding parameters for estrone and estradiol-17β of the “native” and “repurified” proteins and of each charge variant were determined by equilibrium microdialysis. The molar extinction coefficient at 278 nm of each sample was also determined. <span>(1) The “repurified” AFP and each charge variant had a number of binding sites for estrogens close to unity. This increase in the number of sites could neither be explained by the loss of a non-binding isoform (corresponding to 40% of the protein) during chromatography, nor by the existence of complex negative modulatory interactions between isoforms.<ol><li><span>1.</span><span><p>(2) The affinities for estrogens of the “repurified” protein and the two charge variants were slightly decreased compared to that of “native” AFP, except that the “fast” form had the “native” protein's high affinity for estrone—but not for estradiol-17β.</p></span></li><li><span>2.</span><span><p>(3) The molar extinction coefficients at 278 nm of the “repurified” AFP and the isoforms were much lower than that of the “native” protein.</p></span></li></ol></span></p><p>These results suggest that the presence of (an) inhibitor(s) of estrogen binding on the “native” protein which is/are removed by the ion-exchange fast protein liquid chromatography (FPLC) column. A ligand absorbing at 278 nm, which may or may not be the inhibitor, is also removed. The isoform heterogeneity with respect to estrone binding is discussed.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Pages 319-324"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90224-G","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12861786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New nucleic acid techniques","authors":"","doi":"10.1016/0022-4731(90)90235-K","DOIUrl":"https://doi.org/10.1016/0022-4731(90)90235-K","url":null,"abstract":"","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Page 383"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90235-K","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136498333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-resolved fluoroimmunoassay of progesterone in milk","authors":"Maria A. Bacigalupo,&nbsp;Luigi Ferrara,&nbsp;Giacomo Meroni,&nbsp;Adriano Ius","doi":"10.1016/0022-4731(90)90229-L","DOIUrl":"10.1016/0022-4731(90)90229-L","url":null,"abstract":"<div><p>A direct, solid-phase, time-resolved fluoroimmunoassay for progesterone in cow's and goat's milk, using europium-chelate-protein A as a label, is described. The coefficients of correlation with the results by RIA were 0.987 and 0.989.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Pages 357-359"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90229-L","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13538536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The use of HPLC in receptor biochemistry","authors":"","doi":"10.1016/0022-4731(90)90233-I","DOIUrl":"10.1016/0022-4731(90)90233-I","url":null,"abstract":"","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 4","pages":"Page 383"},"PeriodicalIF":0.0,"publicationDate":"1990-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90233-I","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"96048702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Additive and synergistic antitumor effects with toremifene and interferons","authors":"Lauri Kangas,&nbsp;Kari Cantell ,&nbsp;Huub Schellekens","doi":"10.1016/0022-4731(90)90021-J","DOIUrl":"10.1016/0022-4731(90)90021-J","url":null,"abstract":"<div><p>MFC-7 cells were exposed to toremifene, human alpha and gamma interferons and combinations of them <em>in vitro</em>. Growth of the cells was followed by ATP bioluminescence method. Rats bearing DMBA-induced tumors were treated with toremifene, rat gamma Interferon and their combination daily for five weeks. The growth of the tumors was followed by palpation weekly.</p><p>Toremifene and interferons inhibited the growth of MCF-7 cells. Interferons alpha and gamma were additive; toremifene and interferons were additive or at the best synergistic.</p><p>Toremifene inhibited the growth of DMBA-induced tumors. Rat gamma interferon alone had no clear effect on the tumor growth. Combination of toremifene and gamma interferone was the most effective treatment and did not show any detectable toxicity.</p><p>Toremifene and interferons have interesting interactions. Clinical studies using the combination might be warranted.</p></div>","PeriodicalId":17138,"journal":{"name":"Journal of steroid biochemistry","volume":"36 3","pages":"Pages 259-262"},"PeriodicalIF":0.0,"publicationDate":"1990-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-4731(90)90021-J","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13296332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}