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PubMedDate not supplied

Persistence of estrogenic hormones in agricultural soils: I. 17Beta-estradiol and estrone.

The persistence and pathways of dissipation of 17beta-estradiol and estrone in soil were established in laboratory microcosm incubations. [4-14C]-17beta-Estradiol dissipation and mineralization rates were determined over a range of temperatures and moistures, and this compound was rapidly removed in soil conditions typical of a temperate growing season. 17beta-Estradiol was oxidized to estrone in both autoclaved and nonsterile loam, silt loam, and sandy loam soils, suggesting an abiological transformation. In contrast, estrone was stable in autoclaved soil, suggesting that its removal was microbially mediated. Both [4-14C]-17beta-estradiol and [4-14C]-estrone formed non-extractable residues, and soil-bound residues were only slowly mineralized, suggesting that their bioavailability was low. Determination of total estrogenicity in soil extracts by means of a recombinant yeast assay indicated that there were no other estrogenic compounds produced during 17beta-estradiol dissipation, and that total estrogenicity was rapidly dissipated below the detection limit. We suggest that environmental studies evaluating the movement and persistence of estrogenic hormones from animal wastes should include estrone in their analyses.

Agriculture↗
PubMed1986

Estrone treatment dissociates primary versus secondary consequences of "diabetes" (db) gene expression in mice.

Feeding 0.001% estrone in a diet to C57BL/KsJ mice homozygous for the recessive obesity gene "diabetes" (db) permitted dissociation of the primary consequences of obesity gene expression from the secondary consequences of diabetes effected through interaction between the db gene and other diabetogenic genes in the inbred background. Estrone-treated db/db mice were similar to untreated mutants in exhibiting hyperphagia and marked obesity. However, estrone-treated mutants did not develop the hyperinsulinemia, hyperglycemia, and islet atrophy characteristic of untreated db/db mice. Thus, expression of the primary defect could be studied in the absence of the myriad secondary sequelae elicited by chronic hyperinsulinemia and hyperglycemia. Reduced numbers of hepatocyte plasma membrane insulin receptors (50% of normal) persisted in the estrone-treated mice in the absence of hyperinsulinemia, indicating that this deficiency was a consequence of the primary genetic defect and not merely a downregulation phenomenon secondary to hyperinsulinemia. Comparison of insulin secretion from comparably sized +/+ islets versus islets from estrone-treated db/db mice showed no intrinsic defects in beta-cell sensitivity to glucose. In conclusion, db-induced obesity can be dissociated from hyperinsulinemia, hyperglycemia, beta-cell dysfunction, and hyperphagia but is associated with a generalized membrane defect reflected in part by the persistent deficiency of plasma membrane insulin receptors.

Animals↗
PubMed1981

Treatment with oral estrone sulphate in the female climacteric. II. Hormonal aspects.

Of forty-three perimenopausal women aged 40.1-56.5 years with climacteric complaints 25 were treated with sodium piperazine estrone sulphate 2.5 mg daily and 18 were given methyl scopolamine. All subject had initial serum FSH levels in the postmenopausal range (20 U/l). The serum levels of FSH, LH, unconjugated immunoreactive estrogens, total estrone, total dehydroepiandrosterone (DHAS), and the urinary low polar estrogens were followed during 18 months of treatment. In the estrogen treated group serum unconjugated immunoreactive estrogens and total estrone as well as urinary low polar estrogens increased significantly during treatment. The serum levels of FSH decreased significantly during the whole test period; LH only at three months. No effects could be seen on serum DHAS. In the group given methyl scopolamine the only changes found were a decrease in FSH at three months and a positive trend for LH (during the whole treatment period). In the total material, positive correlations were found between pretreatment values of unconjugated immunoreactive estrogens and total estrone and between total estrone and DHAS. A negative correlation was found between unconjugated immunoreactive estrogens and FSH. It is concluded that the effects of estrogens on the endocrine system in peri- and postmenopausal women are influenced by chemical structure, dosage and mode of administration of the estrogen as well as by the endogenous hormone profile.

Adult↗
PubMed1999

[Use of estrone sulfate determination in goat blood for the detection of pregnancy and prediction of fetal number].

The study was carried out on 50 goats of Polish White breed. Blood samples were taken on day 60 after mating from V. jugularis. Pregnancy diagnosis was made using transcutan ultrasound scanning (Pie Medical Scanner 2000 with a 5 MHz curved array probe). The estrone sulphate level was determined by RIA method after extraction and hydrolysis with arylsulphatase/glucuronidase from Helix pomatia. As a threshold value for differentiation of pregnant from nonpregnant goats 1 ng/ml was assumed. In eight nonpregnant goats the estrone sulphate level was 0.61 +/- 0.21 ng/ml. In 42 pregnant goats the level was 6.1 +/- 3.5 ng/ml. The diagnosis was correct in all cases. The number of single, twin and triplet pregnancies was six, 34 and two, respectively. Estrone values in goats with twin pregnancies were significantly higher compared to those with single pregnancies (7.2 +/- 4.1 ng/ml vs. 4.5 +/- 1.8 ng/ml; p < or = 0.01). The results of this study indicate, that the determination of estrone sulphate in blood of goats may be useful for pregnancy diagnosis. The estrone sulphate level in goats with twins is higher, but due to high variation between animals the number of fetuses cannot be exactly predicted.

Animals↗
PubMed2005

Hormone replacement with estradiol: conventional oral doses result in excessive exposure to estrone.

BACKGROUND: There is a lack of consensus about the safety of estrogen replacement therapy, especially with regard to its impact on a woman's risk for breast cancer. Elevated urinary or serum estrone and estradiol concentrations in postmenopausal women are associated with a moderately elevated risk of breast cancer. METHODS: Twenty-four-hour urinary steroid hormone profiles, including the measurement of estrone, estradiol, and estriol, were conducted for 35 postmenopausal women receiving oral estradiol at doses from 0.025-2.0 mg/day. RESULTS: Urinary excretion of estradiol exceeded premenopausal reference range values in women taking estradiol at doses greater than 0.5 mg/day. Urinary estrone excretion exceeded premenopausal reference range values in women taking estradiol doses of 0.25 mg/day or higher. Literature data indicate serum estrone concentrations also markedly exceed premenopausal reference ranges when estradiol is administered orally at a dose of 1 mg/day. CONCLUSIONS: The previously recommended oral dose of estradiol (1-2 mg/day) results in urinary excretion of estrone at values 5-10 times the upper limit of the reference range for premenopausal women. Retrospective studies associating oral estradiol with increased risk of breast cancer may reflect overdose conditions. Based on current knowledge, a prudent dose ceiling for oral estradiol replacement therapy of 0.25 mg/day is proposed.

Administration, Oral↗
PubMed1989

[Tissue culture and estrogen, to clarify the roles of estrone sulfate].

Estrone sulfate (E1-S) has been shown to be quantitatively the most important estrogen in peripheral blood. But, the physiological and/or pathological role of E1-S is not yet clarified. At present, we tried to clarify it using tissue cultures. In tissue cultures of human endometrium, secretory endometrium showed higher activity of estrone sulfatase (E1----E1-S) than proliferative endometrium. Progesterone added in the medium induced an increase of estrone sulfotransferase in the proliferative endometrium. The results suggest a reducing effect of estrogen by progesterone in secretory endometrium in physiological conditions. Estrogen dependent malignant tumors (breast cancer, endometrial cancer) have high estrone sulfatase. It converts E1-S to E1 (----E2) which are abundant in these tumors. Ishikawa cell line increased estrone sulfotransferase activity with progesterone, somewhat like the physiological conditions. From out study in vivo, there is a possibility of some ameliorative effects of E1-S on the central nervous system of patients with senile dementia (Alzheimer's type). Effects of E1-S on central nerves were investigated using tissue cultures.

Alzheimer Disease↗
PubMed1989

Solid-phase enzymoimmunoassay of estrone in saliva.

In this solid-phase enzymoimmunoassay for estrone in saliva, microtiter plates are used after extraction of the sample with diethyl ether. No chromatographic step is involved. The detection limit of the assay is 450 fg per well (33 pmol/L). Intra- and interassay coefficients of variation for the assay of low, medium, and high concentrations of estrone in saliva were respectively 4.2, 12.7; 5.2, 8.7; and 2.7, 5.8%. Using this assay, we found a highly significant correlation (P less than 0.001) between estrone concentrations in time-matched serum and saliva samples. The analytical procedure is rapid and relatively simple. One person can assay 50-60 saliva samples during a normal working day. We conclude that the assay is very suitable, even in small laboratories, for saliva estrone measurements, which, in facilitating serial sampling, enables dynamic observations of estrone concentrations and ovarian activity to be more easily made.

Adult↗
PubMed1986

Effects of estrone infusion on secretion of F series prostaglandins and on function of the corpus luteum during late gestation in cattle.

Catheters were surgically implanted in the carotid artery, jugular vein, and middle uterine vein of 8 cows at 245 days of gestation. Four cows were given 4 mg of estrone/hour via continuous jugular infusion from 0800 hours on day 246 of gestation through 0800 hours on day 250 of gestation; the remaining 4 cows (controls) were given the vehicle for estrone at 10 ml/hour for the same period. Blood samples were collected from the carotid artery every 3 hours during the infusion. Samples were collected hourly from the middle uterine vein from 0 through 8, 54 through 66, and 112 through 120 hours of the infusion periods. After completion of the infusion, corpora lutea were enucleated and blood samples were collected from the carotid artery and uterine vein at hourly intervals for an additional 8 hours. Dispersed cell preparations of the corpora lutea were incubated with and without luteinizing hormone (LH) or dibutyryl cyclic adenosine monophosphate (dbcAMP). Circulating concentrations of unconjugated and conjugated estrone and estradiol-17 beta were higher (P less than 0.05) in the group infused with estrone than in the vehicle-infused group. Mean and base-line concentrations of F series prostaglandins (PGF) for each blood collection period tended to increase (P less than 0.10) during infusion with estrone, but not during infusion with vehicle. After luteectomy, mean and base-line concentrations of PGF also tended (P less than 0.10) to be greater in the estrone-infused cows than in the control cows, but a surge in PGF concentrations due to removal of the ovarian source of progesterone did not develop.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1982

[Enzymatic determination of urinary estrone and estradiol: correlations with plasma estradiol in the menstrual cycle in women].

Enzymatic determination of urine estrone and estradiol concentrations were done daily during a menstrual cycle in six female volunteers. The results were compared with plasma estradiol determined by radioimmunoassay in the same patients. The pattern of estrone and estradiol excretion in morning urine sample fairly reproduced plasma estradiol variations and a good correlation was observed (r = 0.78). The urine pattern of estrone and estradiol variation determined by the enzyme assay can be considered as a good index of oestrogen secretion. The preovulatory peak of estrone and estradiol was observed in urine the day before or the same day as the LH peak. Estrone and estradiol concentration in urine doubled the mean value of the concentration of the follicular phase several days before the LH peak giving a useful indication for prediction of ovulation.

Estradiol↗
PubMed1975

Action of luteinizing hormone-releasing factor (lrf) in the initiation of lordosis behavior in the estrone-primed ovariectomized female rat.

In order to evaluate the precise role of luteinizing hormone-releasing factor (LRF) in mediating the onset of sexual behavior, the specificity, time-course, and dose-response relationship of LRF-facilitated lordosis behavior were determined. Ovariectomized female rats, pretreated with estrone and LRF, displayed a pattern of lordosis behavior which differed little from that produced by estrone-progesterone. Little if any lordosis behavior was observed in response to LRF alone, estrone alone, or estrone in combination with luteinizing hormone (LH), follicle-stimulating hormone (FSH), or thyrotropin-releasing factor (TRF). Furthermore, LRF-induced lordosis behavior occurred in the absence of the adrenals, thus eliminating adrenal progesterone as a factor in facilitating the appearnce of lordosis behavior. The LRF-facilitated lordosis behavior was seen 2 h after the injection of LRF and was maintained for a total of 8 h. A minimal dose of 150 ng LRF was required to initiate the first consistent appearance of lordosis behavior; the maximum response was obtained with 500 ng. It is thus suggested that LRF is not only responsible for the ovulatory discharge of LH and subsequent ovulation, but may also play a role in the initiation of the onset of mating behavior in the female rat.

Adrenal Glands↗
PubMed1991

In vitro effect of synthetic progestogens on estrone sulfatase activity in human breast carcinoma.

The effect of progesterone and nine synthetic progestogens on the activity rate of microsome estrone sulfatase obtained from human breast carcinoma tissues was studied. The progestogens were classified into three groups: group I with a strict inhibitor effect: demegestone and chlormadinone acetate; group II with a strict activator effect: medroxyprogesterone acetate, quingestanol acetate, lynestrenol and progesterone and group III with a nonsignificant effect: dydrogesterone, promegestone, norgestrel and danazol. Demegestone was the most potent inhibitor and medroxyprogesterone acetate and quingestanol acetate had the highest activator effect. The effect of Triton X-100, a nonionic detergent, was also tested. This detergent consistently increased the microsome estrone sulfatase activity. A comparison was made between the effects of demegestone, medroxyprogesterone acetate and danazol on estrone sulfatase activity measured with or without Triton X-100 in the incubation medium. The presence of the detergent modified the progestogen action. Our results suggest that synthetic progestogens can influence the estrone sulfatase activity measured in human breast carcinoma tissues. However, the effect of progestogens was dependent on experimental conditions. Progestogens such as demegestone and chlormadinone acetate which inhibited estrone sulfatase activity in intact preparations, can reduce the intracellular production of biological active estrogen via the sulfatase pathway.

Breast Neoplasms↗
PubMedDate not supplied

Inhibition of estrone sulfatase in human liver microsomes by quercetin and other flavonoids.

Inhibition of estrone sulfatase activity offers the potential for breast cancer prevention therapy by blocking a route to estrogen synthesis. We have investigated the inhibition of this activity by natural flavonoids in a human hepatic microsomal preparation in vitro. The majority of studies were performed with a male liver, but male and female livers exhibited comparable estrone sulfatase activities. The natural flavonoids, quercetin, kaempferol, and naringenin, significantly inhibited estrone sulfatase activity with I50 < 10 microM for the most potent, quercetin. Estrone sulfatase activity in the liver microsomes was biphasic, with a high affinity, low capacity, low concentration activity (Km 14.3 microM, Vmax 0.5 nmol/min/mg protein), probably steroid sulfatase-catalysed, and a low affinity, high capacity, high concentration activity (Km 1.5 mM, Vmax 21.5 nmol/min/mg protein), probably arylsulfatase C or E-catalysed. The former activity was inhibited uncompetitively by quercetin, the latter competitively. Quercetin, a natural dietary constituent, is a potent inhibitor of estrone sulfatase in vitro, and thus has the potential to express antiestrogenic activity in vivo.

Aged↗
PubMed1989

Estrone sulfatase activity in normal and neoplastic endometrial tissues of human uterus.

Estrone sulfatase activity was measured in normal and neoplastic endometrial tissues of human uterus. The tissue homogenates were incubated in air with [3H] estrone sulfate (E1-S, 20 microM) at 37 degrees C for 30 min. After the enzyme reaction was terminated with ethyl ether, the ethyl ether extract was purified by thin-layer chromatography. The apparent Km of sulfatase was 3.0 microM, and the maximum velocity was 14.7 nmol/h/mg protein. Estrone sulfatase activity in endometrial tissues was detected throughout the menstrual cycle with no significant change. Moreover, estrone sulfatase activity in endometrial cells was not stimulated by the addition of progestogen. The enzyme activity in cancer tissue was significantly higher than in normal tissue. Thus we concluded that this enzyme may play a role in regulating the estrogen action by sifting the intracellular equilibrium between free estrogens and estrogen sulfates. We also concluded that in the endometrial cancer tissue, sulfatase appears to act on local production of estrone.

Endometrium↗
PubMed1982

Arylsulphatase C and estrone sulphatase of sheep hypothalamus, preoptic area, and midbrain: separation by hydrophobic interaction chromatography and evidence for differences in their lipid environment.

Arylsulphatase C and estrone sulphatase activities of sheep hypothalamus-preoptic area-midbrain were examined for their susceptibility to phospholipase action. Russel's viper phospholipase A could completely inactivate estrone sulphatase without affecting arylsulphatase C. The latter was partially inactivated by S. aureus phospholipase C but not by C. welchi phospholipase C. Both arylsulphatase C and estrone sulphatase were inactivated to different extents by sodium deoxycholate, which is known to activate the intrinsic phospholipases of brain. Hydrophobic interaction chromatography on phenyl-Sepharose resulted in the differential elution of arylsulphatase C and estrone sulphatase. The results suggest that one enzyme is not responsible for arylsulphatase C and estrone sulphatase activities.

Animals↗
PubMed1981

[The determination of unconjugated estrone, estradiol, estriol and estetrol in serum or amniotic fluid by high performance liquid chromatography with an amperometric detector (author's transl)].

A simultaneous microdetermination of unconjugated estrone, estradiol, estriol and estetrol in serum or amniotic fluid by High Performance Liquid Chromatography with an Amperometric Detector is described. Steroids in serum or amniotic fluid were extracted with 10 volumes of ethyl ether, and then ether extract was evaporated to dryness under N2 gas. After defatting with a mixture of 50% methanol/n-hexane, the methanol phase was evaporated to dryness under N2 gas. The residue was applied to microcolumn packed with 2 ml volume of Sephadex LH-20 in the eluting solvent benzene/methanol (85:15). Fractions contained estrone and estradiol; estriol and estetrol were collected and then evaporated to dryness under N2 gas. The sample solution was applied to HPLC using a reverse phase ODS column and acetonitrile: 0.1M KH2 PO4 47:53 for estrone and estradiol fraction, and 30:70 for estriol and estetrol fraction as a mobile phase, respectively. The fraction of each estrogen was separated completely within a 20 minute period. The limit of detection of estrone, estradiol, estriol and estetrol was 50 pg, respectively.

Amniotic Fluid↗
PubMed2006

Focused libraries of 16-substituted estrone derivatives and modified e-ring steroids: inhibitors of 17beta-hydroxysteroid dehydrogenase type 1.

17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1), an oxidoreductase which has a preferential reductive activity using NADPH as cofactor, converts estrone to estradiol and is expressed in many steroidogenic tissues including breast and in malignant breast cells. As estradiol stimulates the growth and development of hormone-dependent breast cancer, inhibition of the final step of its synthesis is an attractive target for the treatment of this disease. The parallel synthesis of novel focused libraries of 16-substituted estrone derivatives and modified E-ring pyrazole steroids as new potent 17beta-HSD1 inhibitors is described. Substituted 3-O-sulfamoylated estrone derivatives were used as templates and were immobilised on 2-chlorotrityl chloride resin to give resin-bound scaffolds with a multi-detachable linker. Novel focused libraries of 16-substituted estrone derivatives and new modified E-ring steroids were assembled from these immobilised templates using solid-phase organic synthesis and solution-phase methodologies. Among the derivatives synthesised, the most potent 17beta-HSD1 inhibitors were 25 and 26 with IC50 values in T-47D human breast cancer cells of 27 and 165 nm, respectively. Parallel synthesis resulting in a library of C5'-linked amides from the pyrazole E-ring led to the identification of 62 with an IC50 value of 700 nM. These potent inhibitors of 17beta-HSD1 have a 2-ethyl substituent which will decrease their estrogenic potential. Several novel 17beta-HSD1 inhibitors emerged from these libraries and these provide direction for further template exploration in this area. A new efficient diastereoselective synthesis of 25 has also been developed to facilitate supply for in vivo evaluation, and an X-ray crystal structure of this inhibitor is presented.

17-Hydroxysteroid Dehydrogenases↗
PubMedDate not supplied

Serum estrone, estradiol and estriol concentrations during oral hormone therapy after oophorectomy.

Serum estrone, estradiol and estriol concentrations during estradiolvalerate-norgestrel therapy for women who have undergone oophorectomy were studied. The patients in one group received 1 mg of estradiolvalerate in the morning and 2 mg of estriolsuccinate in the evening. The estrone and estradiol concentrations of the first and fifth day were at roughly the same level and the treatment caused no estrogen cumulation. The estriol concentrations on the fifth day were distinctly higher than on the first, owing to the conversion of estrone and estradiol into estriol. The other group of women were placed on a regimen of 2 mg of estradiolvalerate plus 0.5 mg of norgestrel in the morning and 2 mg of estriolsuccinate in the evening. Here again, the estrone and estradiol concentrations on the first and fifth days were similar.

Castration↗
PubMed1999

Human estrogenic 17beta-hydroxysteroid dehydrogenase: predominance of estrone reduction and its induction by NADPH.

Human estrogenic 17beta-hydroxysteroid dehydrogenase (17beta-HSD1) plays a crucial role in the last step of the synthesis of estrogens. A detailed kinetic study demonstrated that the enzyme shows about 240 fold higher specificity towards estrone reduction than estradiol oxidation at physiological pH using tri-phosphate cofactors. The kcat/Km values are 96 +/- 10 and 0.4 +/- 0.1 s-1 (microM)-1 respectively for the above two reactions. However, it has been shown that this difference is closely linked to the use of NADPH and NADP cofactors. A binding study using equilibrium dialysis indicated similar KD (equilibrium dissociation constant) of 11 +/- 1 and 4.7 +/- 0.9 microM for estrone and estradiol, respectively. The binding affinity of 17beta-HSD1 to estrone was significantly increased with a KD of 1.6 +/- 0.2 microM in the presence of NADP, the latter used as an analogue of the NADPH. The results of binding studies agree with the steady-state kinetics, which showed that the Km of estrone is 12-fold lower when using NADPH as a cofactor than when using NADH. These results strongly suggest that the cofactor plays a crucial role in the stimulation of the specificity for estrogen reduction.

17-Hydroxysteroid Dehydrogenases↗