Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.6.1 (sulfatase)
3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The conversion of estrone sulfate (E1S) to estrone (E1) was measured during the in vitro incubation of the labeled sulfoconjugate with implantation sites (IS) and nonimplanted regions (NIS) of uterine horns from 6-day pregnant rats. Extensive metabolism of E1S occurred in both tissues, being noticeably less (29.31%) in IS than in NIS. Estrogen sulfatase activity present in the uterus of ovariectomized virgin rats was found to be higher than in both uterine regions of the pregnant rats. We suggest that E1S present in uterine fluids may be accessible to be metabolized into unconjugated estrogens by both intrauterine tissues of 6-day pregnant rats. This metabolism could be locally modulated in IS through the participation of the estrogen sulfatase, the activity of which is in turn controlled by the presence of free estrogens, possibly synthesized and/or secreted by the embryo, which has been shown to inhibit the sulfohydrolase activity.
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PMID:Uterine estrogen sulfatase activity at the time of blastocyst implantation in the rat. 206 64

The possible role of intrauterine estrogen sulfatase and steroid sulfatase around the time of parturition in the guinea pig was investigated. [3H]Estrone sulfate or [3H]pregnenolone sulfate was incubated with intrauterine tissues. Estrogen sulfatase was found in placenta, endometrium, decidua basalis, amnion and chorion. The presence of steroid sulfatase was established in endometrium and decidua basalis but not in placenta or the fetal membranes. Examination of activities in early (days 32-35), mid (days 44-46) and late (within 5 days of parturition) gestation revealed no significant change in estrogen sulfatase specific activity in decidua basalis. However, in chorion and endometrium this activity was seen to increase approx. 12-fold (P less than 0.001) and 2.8-fold (P less than 0.001), respectively, from early to late gestation. In placenta, estrogen sulfatase activity appeared to increase 2.4-fold (P less than 0.001) and in amnion it decreased 2.8-fold (P less than 0.002). Steroid sulfatase activity in decidua basalis did not change during gestation, while activity in endometrium was found to increase by a factor of 5.3 (P less than 0.001), from early to late gestation. The increases, both in estrogen sulfatase activity in chorion, endometrium and placenta and in steroid sulfatase activity in endometrium, occurred primarily within the final 3 weeks of gestation. In contrast, the decrease in estrogen sulfatase activity in amnion occurred principally between the fifth and sixth weeks of gestation. Analysis of radiolabelled metabolites indicated that estradiol and progesterone could be produced via estrogen sulfatase and steroid sulfatase activities in certain tissues. Subcellular fractionation of tissues revealed that the greatest specific activity and total activity, in all cases, was associated with the 105,000 g pellet. Significant activity was also detected in the 750 and 10,000 g pellets but not in the 105,000 g supernatant. Radioimmunoassay of endogenous estradiol-17 beta (estradiol) in chorion extracts revealed a 6.3-fold increase in the hormone from mid to late gestation. Estradiol levels in endometrium and myometrium did not appear to change during this time. It was concluded that increased estrogen sulfatase activity in guinea pig chorion in late gestation occurs along with elevated levels of the hormone estradiol which may be important for parturition in this species.
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PMID:Estrogen sulfatase and steroid sulfatase activities in intrauterine tissues of the pregnant guinea pig. 227 54

Estrogen sulfates are quantitatively the most important form of circulating estrogens during the menstrual cycle and in the post-menopausal period. Huge quantities of estrone sulfate and estradiol sulfate are found in the breast tissues of patients with mammary carcinoma. It has been demonstrated that different estrogen-3-sulfates (estrone-3-sulfate, estradiol-3-sulfate, estriol-3-sulfate) can provoke important biological responses in different mammary cancer cell lines: there is a significant increase in progesterone receptor. On the other hand, no significant effect was observed with estrogen-17-sulfates. The reason for the biological response of estrogen-3-sulfates is that these sulfates are hydrolyzed, and no sulfatase activity for C17-sulfates is present in these cell lines. [3H]Estrone sulfate is converted in a very high percentage to estradiol (E2) in different hormone-dependent mammary cancer cell lines (MCF-7, R-27, T-47D), but very little or no conversion was found in the hormone-independent mammary cancer cell lines (MDA-MB-231, MDA-MB-436). Different anti-estrogens (tamoxifen and derivatives) and another potent anti-estrogen: ICI 164,384, decrease the concentration of estradiol very significantly after incubation of estrone sulfate with the different hormone-dependent mammary cancer cell lines. No significant effect was observed for the uptake and conversion of estrone sulfate in the hormone-independent mammary cancer cell lines. Progesterone provokes an important decrease in the uptake and in estradiol levels after incubation of [3H]estrone sulfate with the MCF-7 cells. It is concluded that in breast cancer: (1) Estrogen sulfates can play an important role in the biological response of estrogens; (2) Anti-estrogens and progesterone significantly decrease the uptake and estradiol levels in hormone-dependent mammary cancer cell lines; (3) The control of the sulfatase and 17 beta-hydroxysteroid dehydrogenase activities, which are key steps in the formation of estradiol in the breast, can open new possibilities in the treatment of hormone-dependent mammary cancer.
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PMID:Importance of estrogen sulfates in breast cancer. 256 May 11

Two estrogen sulfatases, arylsulfatase C-estrone sulfatase (ASC-ES) and d-equilenin sulfatase (EqS) were demonstrated histochemically in the normal human female breast, in benign breast diseases and in infiltrating mammary ductal carcinomas to study their significance in the pathogenesis of epithelial proliferations. By hydrolyzing estrone sulfate, the amount of which in female blood is about ten times greater than that of estradiol or estrone, estrogen sulfatases can produce a high local concentration of estrogens. A simultaneous azo-coupling method for histochemical demonstration of ASC-ES is described in the present study; EqS was demonstrated by a previously described method. Estrogen sulfatases were not found in the normal female breast. Both estrogen sulfatases were found in epithelial cells in some examples of mastopathic disease and in fibroadenomas, while ASC-ES was found in periductal fibroblasts. In some cases of infiltrating ductal carcinomas, estrogen sulfatases were present in carcinoma cells. In most of these tumors ASC-ES activity was observed in fibroblasts around infiltrative cell cords. There was no correlation between the presence of estrogen sulfatases and of hormone receptors in carcinomas. It is concluded that estrogen sulfatases play no role in the early stages of benign or malignant epithelial proliferations. However, the induction of estrogen sulfatases may promote epithelial proliferation in some cases if estrogen receptors are present in epithelial cells.
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PMID:Histochemistry of estrogen sulfatases in human breast diseases. 286 35

The availability of the oral contraceptive steroids ethinyl estradiol (EE) and levonorgestrel in plasma after a single dose of 1 g paracetamol (acetaminophen) was quantitated. 6 women aged 21-24 who had been taking combined oral contraceptives for at least 3 months took a single dose of 1 g paracetamol, followed 1 hour later by a single dose of Ovran (50 mcg EE and 250 mch levonorgestrel) after an overnight fast. EE and levonorgestrel were radioimmunoassayed, and EE sulfate was determined by radioimmunoassay after incubation with sulfatase. In blood sampled over a 24 hour period, the area under the concentration curve for EE during the 1st 3 hours rose significantly after paracetamol (22%, p0.05). EE sulfate concentration was significantly lower (p0.05). There was no change in plasma concentration of levonorgestrel. The results suggest that paracetamol increases circulating EE by limiting available sulfation of the steroid.
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PMID:Paracetamol interaction with oral contraceptive steroids: increased plasma concentrations of ethinyloestradiol. 311 13

Aromatase has been identified in the telostean, avian, and mammalian pituitaries, although its cellular location(s) is not yet certain. To address this question, experiments were performed in tilapia (Oreochromis mossambicus), a species which has been well characterized with respect to the intraglandular distribution of the different pituitary cell types. To estimate aromatase, glands were microdissected into rostral pars distalis (RPD), proximal pars distalis (PPD), and neurointermediate lobe (NIL) and organs were cultured in the presence of [3H]androstenedione for 16-24 hr. [3H]Estrogen products were isolated and quantified after ether extraction, hydrolysis with glucuronidase-sulfatase, thin-layer chromatography, and phenolic partition. Authentic estrone or estradiol-17 beta were produced by all pituitary regions and also by the urophyseal region of the spinal cord. Aromatase was two to five times higher in PPD than in RPD or NIL and similar to activity in adjacent hypothalamus-preoptic area (HPOA). Much lower estrogen yields were obtained in cultures of cerebellum, urophysis, and other cord regions. Since the PPD contains most of the somatotropes, these data are consistent with earlier studies implicating GH3/GH4 cell strains as an enriched enzyme source, although its presence in other cell types cannot be ruled out. The unusually high and localized aromatase in tilapia pituitary renders this species a useful model for studying the targets and functional importance of estrogen as a parahormone in the pituitary.
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PMID:Aromatase is concentrated in the proximal pars distalis of tilapia pituitary. 341 Feb 99

Estrogen sulfatase (ES) and estrogen sulfotransferase (ESFT) activities were measured in a group of primary breast tumors. The mean value of ES activities, measured in 66 breast tumor specimens, was 0.9 nmol of estrone formed from estrone sulfate/mg tissue protein per hr regardless of the hormone receptor status of the specimen. However, the average value of the ESFT activity, expressed in nmol of estradiol-3-sulfate (E2S) formed from estradiol (E2)/mg of cytosol protein per hr, was found to be significantly higher in ER +/PGR + tumors (n = 26, 0.18 +/- 0.15, means +/- SD) than in ER -/PGR - tumors (n = 31, 0.08 +/- 0.06, P less than 0.005). Normal breast tissues also contain ES and ESFT but the activities were lower than those in tumors. When fresh breast tumor tissue fragments were incubated with radioactive E2 (0.4 nM) and E2S (3 nM) separately, E2 was not sulfurylated appreciably while E2S was extensively hydrolyzed to free estrogens indicating that the combined effect of ES and ESFT in breast tumor is favored towards the hydrolysis of estrogen sulfate. These results imply that the circulating estrogen sulfate could be utilized as the precursor of active estrogen to promote the cell growth in hormone sensitive tumors.
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PMID:Estrogen sulfatase and estrogen sulfotransferase in human primary mammary carcinoma. 658 May 11

Estrogen metabolism was studied in a newly established cell line (RL95-2) derived from a human endometrial carcinoma. Estradiol and estrone were metabolized to water-soluble derivatives by cells under in vitro culture conditions. Between 80-90% of the added steroids were metabolized, with nearly quantitative recovery of the products from the incubation medium. Arylsulfatase treatment converted the metabolites to ether-soluble forms, whereas beta-glucuronidase had no effect on the aqueous solubility of these compounds. Butanol extracts of the water-soluble estradiol metabolites cochromatographed on high performance liquid chromatography with 17 beta-estradiol-3-sulfate (93.6%) or estrone-3-sulfate (3.5%). No more than 6% of the estradiol added to the incubation medium was recovered in the form of estrone, either as estrone or estrone sulfate. After arylsulfatase treatment of the estradiol conjugates, 92% of the ether-soluble radioactivity cochromatographed with estradiol, and 3.8% cochromatographed with estrone. Estrogen-sulfurylating activity was localized in the cytosol of subcellular fractions of RL95-2 cells. The sulfoconjugation of estrogens by RL95-2 cells may prove useful as a model for the investigation of estrogen metabolism in endometrial carcinoma cells.
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PMID:Estrogen sulfoconjugation by human endometrial cancer cells (RL95-2) in culture. 669 41

Estrone and estradiol concentrations in breast tumor tissue are an order of magnitude higher than circulating plasma levels in postmenopausal women with breast cancer. Local production of estrogen in the neoplastic tissue is one of several possible explanations for this plasma/tissue gradient. This study evaluated breast tumor estrogen production via the estrone sulfate to estrone (sulfatase) pathway and compared this with the androstenedione to estrone (aromatase) system in human and rodent mammary tumors. Estrogen production from estrone sulfate was related linearly with time and tissue concentrations, exhibited an apparent Km of 20 microM, and produced a linear Eadie-Hofstee kinetic plot consistent with a single class of enzymatic sites. Measurement of sulfatase in 35 human breast tumors using enzyme saturating conditions revealed estrone production ranging from 0.8-125 mumol/g protein . h. The corresponding range in host mammary tumors was 3.5-7.1 mumol/g protein . h. In human breast tumors, sulfatase activity did not correlate with the levels of estrogen receptor or progesterone receptor. Comparison of sulfatase with aromatase activity in human tumors at physiological levels of substrate revealed estrone formation via sulfatase of 2.8 pmol estrone produced/g protein . h, while aromatase produced only 0.27 pmol/g protein . h. In rat mammary tumors, sulfatase activity was similar to that in human tumors, whereas aromatase activity could not be detected, even with a highly sensitive assay. Thus, estrone sulfatase appears to be the enzyme primarily responsible for intratissue estrone production in hormone-dependent breast carcinomas.
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PMID:In situ estrogen production via the estrone sulfatase pathway in breast tumors: relative importance versus the aromatase pathway. 672 22

Although considerable information is available concerning steroidogenesis in the human fetus, the function of the different steroids formed during pregnancy and the factors regulating this delicate hormones balance are poorly understood. During human pregnancy, the placenta synthesizes large quantities of progesterone, estradiol, estrone and estriol and secretes these hormones into both the maternal and fetal circulations; progesterone from maternal lipoprotein-cholesterol, estradiol and estrone from maternal and fetal dehydroepiandrosterone sulfate (DHAS), and estriol largely from fetal 16 alpha-OH-DHAS. It has been demonstrated that preimplantation blastocysts of several animal species have the capacity to accumulate steroids to pregnenolone to progesterone, and to interconvert estrone and estradiol. Estetrol (E4), 15 alpha-hydroxy derivative of estriol is an interesting compound, since its formation is relatively unique to fetal liver function. Of special interest is that placental sulfatase deficiencies result in an extension of the gestation, and Cesarean section has to be done. This raises the question of the role of estrogens in determining the onset of labor, much as in the case of anencephaly. In general, progesterone may decline prior to an abortion, but there has not been a direct application to clinical practice. Estrogen levels during pregnancy are influenced by factors other than fetal well-being and include fetal weight, placental enzyme function, fetal adrenal function, maternal intestinal flora, maternal renal excretion and maternal liver function. Although not yet extensively utilized, such a dynamic test as the infusion of DHAS may yield useful information within a short period in otherwise complicated cases related to fetal and placental function.
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PMID:[Endocrino-pharmacological study of reproduction: Role and biosynthesis of steroid hormones in the feto-placental unit]. 676 83


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