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PubMed1976

[Comparative studies on oral glucose tolerance and serum lipids under the influence of a new oral contraceptive (SH B 209 AB: 2 mg cyproterone acetate + 0.05 mg ethinyl estradiol), the combination D-norgestrel/ethinyl estradiol and in a control group (author's transl)].

24 healthy women given the combination of cyproterone acetate (2 mg) + ethynyl estradiol (0.05 mg) [SH B 209 AB] and D-norgestrel (0.25 mg) + ethinyl estradiol (0.05 mg) [Neogynon] were compared with a control group in oral glucose tolerance tests. The volunteers were divided into three groups. Two received alternately both preparations with each treatment cycle preceded by one cycle without medication. The third group served as an independent control. On the 25th day of each cycle blood was withdrawn before and 15, 30, 45, 60, 90 and 120 min after the carbohydrate load. Blood glucose and insulin and free fatty acids in serum were determined. Fasting values of triglycerides and cholesterol in serum were determined. The following results were obtained: 1. The mean fasting levels of blood glucose, serum insulin and free fatty acids were unchanged. 2. The total area under the blood glucose curve over the initial value was not altered 2 h after treatment with SH B 209 AB or Neogynon. The total area under the insulin and free fatty acids curves were also unchanged after the oral glucose load. 3. There was no change in serum cholesterol. 4. Serum triglycerides were significantly increased after SH B 209 AB. 5. The implications of the structural differences between both gestagens are discussed.

Blood Glucose↗
PubMed2005

The estrogen antagonist ICI-182-780 does not inhibit the transformation phenotypes induced by 17-beta-estradiol and 4-OH estradiol in human breast epithelial cells.

Prolonged unopposed estrogen exposure is a widely accepted risk factor in breast cancer development. However, the mechanisms through which estrogens induce breast carcinogenesis have not been definitively unraveled. For testing whether estrogens exert their transforming effects through a non-receptor-mediated mechanism, we have treated the spontaneously immortalized human breast epithelial cells MCF-10F, which are estrogen receptor alpha negative, with 17-beta estradiol (E(2)) or its metabolite 4-OH-estradiol (4-OH-E(2)), each one either alone or in combination with the antiestrogen ICI-182-780. Treated cells were maintained for several passages in culture and evaluated for colony formation in agar-methocel (CE), tri-dimensional growth in collagen matrix, invasiveness in matrigel, and cell cycle analysis by flow cytometry. Both E(2) and 4-HO-E(2), at all the doses tested, in the presence or absence of ICI-182-780, increased CE and decreased the cells' ductulogenic capacity. They also increased the invasiveness and the number of cells in the S phase of the cell cycle. Our data clearly demonstrate that E(2) and 4-OH-E(2) increase cell proliferation and induce transformation in MCF-10F cells, phenomena that are not abrogated by ICI-182-780. The failure of the antiestrogen to abrogate the transformation phenotypes led us to hypothesize that estrogen-induced transformation is occurring by a non-estrogen receptor alpha-mediated process, more probably through the genotoxic effect of the estrogen metabolite 4-HO-E(2).

Agar↗
PubMed2006

Randomized comparison of lower and standard dosages of transdermal estradiol on serum estradiol levels and vaginal maturation index.

OBJECTIVE: To evaluate serum estradiol (E2) in postmenopausal women who received 0.025 mg/d or 0.05 mg/d transdermal estradiol, in an equivalent trial. MATERIAL AND METHOD: One hundred and eight postmenopausal women were randomized into 0.025 mg/d and 0.05 mg/d of transdermal E2 matrix patch. After 12 weeks, serum E2 and vaginal maturation index (VMI) were checked in both groups. Adverse effects, such as breast tenderness, application site reaction, weight gain, and headache, were also assessed. RESULTS: Serum E2 in 0.025 mg/d and 0.05 mg/d groups were 42.43 +/- 35.11 and 48.41 +/- 22.36 pg/mL, respectively. There was no statistically significant difference between the groups. Equivalence was found under CI of +/- 14 pg/mL. Mean value of superficial cells and vaginal maturation index (VMI) were comparable between both groups. Adverse effects seem to be less in the lower dosage group compared to the standard dosage group. CONCLUSION: The lower dosage (0.025 mg/d) of the transdermal E2 matrix system is probably an appropriate treatment option for postmenopausal women who need minimal effective and minimal adverse effects.

Administration, Cutaneous↗
PubMed1989

[The effect of estradiol on the activity of cAMP-dependent protein kinase in cells of estradiol-dependent tumors of the rat mammary gland. The role of a thermally stable protein inhibitor of cAMP-dependent protein kinase].

Stimulation of rat mammary tumour growth by estradiol is due to the activation of the adenylate cyclase system and cAMP-dependent protein kinases. A single administration of estradiol to ovariectomized rats causes a rise in the cAMP-dependent protein kinase activity in cell nuclei within the first 4-6 hours after injection. This effect is probably due to the translocation of enzymes into nuclei and an increase of their synthesis. The high level of the cAMP-dependent protein kinase activity in cell nuclei was observed in actively growing intact mammary tumours, in contrast to regressing ones in ovariectomized animals. This phenomenon can be accounted for by the decrease in the content of a thermostable protein inhibitor of cAMP-dependent protein kinases rather than by the high level of cAMP.

Adenylyl Cyclases↗
PubMed1984

Estradiol-17 beta and estradiol-17-glucosiduronate before and at delivery.

The maternal peripheral serum level of estradiol-17 beta (E2), which reaches a peak a few weeks before delivery, may play a role in initiating delivery. In this study, the steroidal activity regulated by both the production and conjugation was estimated by measuring estradiol-17-glucosiduronate (E2-17-G), E2, estriol-16-glucosiduronate (E3-16-G), and estriol (E3) before and at delivery. At delivery, levels of E2 and E2-17-G were higher in the maternal peripheral vein (MP) than in the umbilical vein (UV) and umbilical artery (UA), but those of E3 and E3-16-G were higher in UV and UA than in MP. These results suggested that the production and conjugation of E2 were mainly regulated on the maternal side, but those of E3 were regulated mainly in the feto-placental unit. The ratios of E2/E2-17-G in MP were or became high a few weeks before delivery but decreased remarkably as pregnancy progressed to delivery. The activity of E2 seems to be regulated at least in part by conjugation in late pregnancy and at delivery.

Cross Reactions↗
PubMed2000

Comparative estrogenicity of estradiol, ethynyl estradiol and diethylstilbestrol in an in vivo, male sheepshead minnow (Cyprinodon variegatus), vitellogenin bioassay.

An in vivo bioasssay for vitellogenin (VTG) synthesis was developed to screen individual chemicals or mixtures of chemicals for potentially estrogenic effects in a marine teleost model. An enzyme-linked immunosorbent assay (ELISA) was used to quantitate VTG synthesis in male sheepshead minnows (Cyprinodon variegatus) exposed to five concentrations of the natural estrogen (17beta-estradiol), a synthetic, steroidal pharmaceutical estrogen (17alpha-ethynyl estradiol), or a synthetic, non-steroidal, pharmaceutical estrogen (diethystilbestrol) for 16 days. At an exposure concentration of 20 ng/l, only diethystilbestrol elicited a vitellogenic response. At all test concentrations greater than 100 ng/l, VTG appeared in the plasma in a dose-dependent manner for the three estrogen treatments. Liver VTG mRNA measurements were also made, exhibiting no clear correlations between quantities, nor temporal appearance of the message and mature protein were apparent. This assay is short-term, relatively inexpensive, shows a direct response, and easily quantitated.

Journal Article↗
PubMed1994

Clinical comparison of monophasic oral contraceptive preparations of gestodene/ethinyl estradiol and desogestrel/ethinyl estradiol. Latin American Oral Contraceptive Study Group.

The efficacy, cycle control, subjective complaints, and safety of monophasic preparations of the oral contraceptives containing gestodene 75 mcg plus ethinyl estradiol 30 mcg versus desogestrel 150 mcg plus ethinyl estradiol 30 mcg were compared in a 6-cycle, open-label, parallel, randomized, multicenter phase IV clinical study in Latin America. Of a total of 176 women in each group, 163 in the gestodene group and 160 in the desogestrel group completed 6 cycles, providing data for 1,015 and 1,006 cycles, respectively. Subject compliance was excellent; pills were missed during only 6.9% of the cycles in each group. No woman became pregnant during the study. Gestodene group exhibited significantly better cycle control as evidenced by the lower incidence of breakthrough bleeding and spotting. Spotting in some cycles was reported by 11.9% of women taking the gestodene-combination compared with 21% of women taking the desogestrel-combination. Based on number of women, 86.4% of the gestodene group reported all cycles were normal (no BTB) compared with 76.7% of the desogestrel group. Also, the women in the gestodene group reported a significantly lower incidence of nuisance side effects during treatment cycles. No amenorrhea was observed for either group. There were no clinically significant differences between groups with respect to body weight, blood pressure, or laboratory evaluations. Seven women withdrew from the gestodene group and 8 women withdrew from the desogestrel group because of adverse reactions. The results of this study indicate that, although both OCs provided effective contraception, in comparison to the desogestrel-combination, the gestodene-containing OC is associated with better cycle control, less bleeding, and fewer subjective complaints.

Adolescent↗
PubMed1985

Progesterone-mediated suppression of estradiol receptors in cynomolgus macaque cervix, endometrium and oviduct during sequential estradiol-progesterone treatment.

We used sequential treatment with implants of estradiol (E2) and progesterone (P) to create varied hormonal states in a group of spayed cynomolgus macaques. The reproductive tracts were removed, and nuclear and cytosolic estrogen receptors were analyzed in the cervical mucosa, endometrium, and oviducts. Nuclear receptor quantities were greater in tissues of E2-treated monkeys than in tissues of spayed animals. Sequential P treatment, even in the presence of continuous E2, decreased the amounts of nuclear and cytosolic E2 receptors. In the oviduct and endometrium, the P-mediated suppression of receptors occurred within 1 or 2 days. In the cervix, suppression occurred only if the serum P:E2 ratio was elevated to twice the amount (approximately 100:1) usually found during the luteal phase of the menstrual cycle (approximately 50:1) in this species. Of these three reproductive tract tissues, the cervix had the highest threshold for suppression by P of E2 receptors in the presence of E2.

Animals↗
PubMed2002

The effect of extending the pill-free interval on follicular activity: triphasic norgestimate/35 micro g ethinyl estradiol versus monophasic levonorgestrel/20 micro g ethinyl estradiol.

This study was designed to evaluate follicular activity in women taking oral contraceptives with imposed imperfect compliance. After completing a 28-day cycle of either triphasic norgestimate/EE (NGM/EE) (Ortho Tri-Cyclen, Ortho-McNeil Pharmaceutical, Raritan, NJ) or monophasic levonorgestrel/EE (LNG/EE) (Alesse, Wyeth-Ayerst Laboratories, Philadelphia, PA), women were instructed to intentionally "miss" the first two active pills of the next pack. The first two tablets in the second treatment cycle were deliberately omitted, thereby extending the pill-free interval from 7 days to 9 days. Subjects were randomized to take NGM/EE (n = 40) or LNG/EE (n = 39) for two consecutive cycles. The mean maximum follicular diameter was significantly greater in women taking LNG/EE than in those taking NGM/EE (16.4 +/- 7.1 mm vs. 12.6 +/- 8.3 mm, p = 0.047). The LNG/EE group had significantly higher median serum estradiol concentrations compared to women taking NGM/EE on pill Days 10 [29.5 pg/mL (range: 10.0-540.0 pg/mL) vs. 2.5 pg/mL (range: 2.0-6.0 pg/mL), p < 0.001] and 14 [11.0 pg/mL (range: 2.0-416.0 pg/mL) vs. 2.0 pg/mL (range: 2.0-3.0 pg/mL), p = 0.001]. Two women in the NGM/EE group and three women in the LNG/EE group had at least one progesterone level > or =3 ng/mL; none of these women demonstrated a maximum follicular diameter >13 mm. Significantly greater follicular activity was observed after an extended pill-free interval in women taking LNG/EE compared to those taking triphasic NGM/EE. The clinical implications of these findings require further study.

Adolescent↗
PubMed1992

Aromatase activity and estradiol in human breast cancer: its relationship to estradiol and epidermal growth factor receptors and to tumor-node-metastasis staging.

PURPOSE: The present report attempts to clarify whether there is a relationship between aromatase activity (ARAC) and estradiol (E2), hormonal receptors, E2 receptor (ER), and epidermal growth factor receptor (EGFR), as well as with tumor stage and histopathology in human breast cancers. MATERIALS AND METHODS: We studied 225 breast carcinomas, 67 of which were premenopausal and 158 postmenopausal. In each sample, ARAC, EGFR, ER, and E2 were quantified. ARAC was quantified by Thompson and Siiterii's method, EGFR was quantified with a two-point assay method using radioactive iodine (125I)-EGF as ligand, and ER was measured by the Scatchard method using 3H-E2. E2 was quantified by radioimmunoassay in the diethylether tumor extract. RESULTS: ARAC was found in 64% of the cancers studied. There is a strong direct association between ARAC and tumor size in postmenopausal patients (P = .001). In the postmenopausal group, the proportion of ARAC-positive (ARAC+) tumors is significantly higher among ER-positive (ER+) than ER-negative (ER-) ones (P less than .001). ER+ tumors also have significantly higher levels of E2 than do ER- ones (P less than .0001); similarly, ARAC+ tumors have significantly higher levels of E2 than do ARAC- ones (P less than .0001). There is a significant multiple linear correlation between the log of the levels of ARAC, ER, and EGFR and the log of tumor E2 (P less than .0001). The correlation coefficients obtained show that ARAC and ER have a positive effect on tumor E2. CONCLUSION: The results obtained suggest the importance of tumor ARAC in the tumoral levels of E2 and reinforce the possible biologic significance of tumor ARAC, especially in postmenopausal breast carcinoma patients.

Adult↗
PubMed1984

Nuclear estradiol and cytosol progestin receptor concentrations in the brain and the pituitary gland and sexual behavior in ovariectomized estradiol-treated middle-aged rats.

We wished to determine whether the altered nuclear estradiol (E2) receptor concentrations in middle-aged rats can explain the diminished responsiveness to E2 observed in aging rats. Therefore, we measured receptor concentrations in various brain areas and the pituitary gland of young and middle-aged ovariectomized rats 2 and 4 days after implantation of Silastic capsules containing E2. To determine whether any observable changes had physiological consequences, we correlated age-dependent changes in E2 nuclear receptor concentrations with two E2-dependent parameters: cytosol progestin receptor levels in equivalent brain areas and pituitary gland and progesterone-facilitated reproductive behaviors. Young (3-4 months old) and middle-aged (10-12 months old) Sprague-Dawley rats were ovariectomized and received Silastic capsules containing E2 dissolved in oil 1 week later (day 0). Groups of rats were killed at 1200 h on either day 2 or day 4. Nuclear E2 and cytosol progestin receptor concentrations were assessed in a nuclear and cytoplasmic extract from the medial basal hypothalamus, preoptic area, amygdala, and pituitary gland. To test steroid-induced mating behavior, ovariectomized young and middle-aged rats were treated with E2-containing capsules for 2 or 4 days. At 0900 h progesterone (0.2 mg/kg BW) was injected sc and receptive and proceptive behaviors were observed when experienced males were introduced 4-6 h later. Two days after implantation of E2 capsules, middle-aged rats exhibited lower nuclear E2 receptor concentrations in the medial basal hypothalamus and preoptic area than young rats. By day 4, there were no significant age-related differences in any brain area or in the pituitary gland. Parallel age-related differences were observed in cytosol progestin receptor concentrations on day 2 but they were not evident by day 4. Similarly, middle-aged rats exhibited deficits in proceptive behavior, lordosis quotient, and lordosis quality score on day 2, but there were no differences compared to young rats on day 4. These data demonstrate that E2-induced nuclear E2 receptor concentrations are lower in selected areas of the brain of middle-aged rats. Such changes appear to be physiologically important because they are correlated with changes in E2-induced cytosol progestin receptor concentrations and steroid-induced behaviors. Furthermore, they may partially account for age-related differences in E2-induced LH surges on day 2.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMed2006

Stimulation of estradiol glucuronidation: a protective mechanism against estradiol-mediated carcinogenesis?

17beta-Estradiol (E2) and its catechol and methoxy metabolites are believed to play important roles in the mechanism of E2-mediated tumor formation. Because conjugation with glucuronic acid lowers tissue levels by facilitating excretion, we have determined the kinetic parameters of the glucuronidation of E2, estrone (E1), and seven phase I metabolites using human liver microsomes. The catechol estrogens 2- and 4-hydroxy-E2/E1 exhibited the highest clearance, exceeding that of E2, E1, and the methoxy metabolites by factors of 6-44. Homotropic activation kinetics were observed for the 3-glucuronidation of E2 but not for any of the metabolites. None of the metabolites affected the kinetics of the 3-glucuronidation of E2. In contrast, the isoflavone daidzein stimulated the formation of E2-3-glucuronide, as has been reported previously. This heterotropic activation by daidzein appears to be specific for the glucuronidation of E2 because daidzein did not affect the glucuronidation of the 2- and 4-hydroxy metabolites of E2. However, daidzein may lower the glucuronidation of 2-methoxy-E2 in vivo due to its preferential glucuronidation. The decreased tissue levels of E2 and increased concentrations of 2-methoxy-E2, as implied by this study and the previous one, may contribute to the protective effect of daidzein against breast and endometrial cancer.

Breast Neoplasms↗
PubMed2005

Area under the curve for estradiol levels do not consistently reflect estradiol levels on the day of hCG administration in patients undergoing controlled ovarian hyperstimulation for IVF-ET.

PURPOSE: Most studies reported estradiol (E2) levels attained on day of hCG administration when investigating effect of E2 on IVF outcome. We studied whether a relationship exists between the area under the curve for E2 levels (AUC-E2) and E2 levels on hCG day during IVF-ET. METHODS: Retrospectively, we analyzed data for 313 patients who completed one IVF-ET cycle each. Patients were sorted according to AUC-E2 levels. Then we compared between each patient's own AUC-E2 and the corresponding E2 level on hCG day for the same patient. RESULTS: Although overall AUC-E2 correlated positively with E2 levels on hCG day, there was no consistent correlation between individual patients. CONCLUSIONS: AUC-E2 reflects more accurately the amount of E2 produced by the follicles during controlled ovarian hyperstimulation. The absence of a uniform correlation between AUC-E2 and E2 on hCG day may result in different conclusions when studying outcomes of IVF treatment.

Area Under Curve↗
PubMed2006

Apoptotic and anti-proliferative effects of 17beta-estradiol and 17beta-estradiol-like compounds in the Hep3B cell line.

Since there is evidence for estrogen and estrogen-like compounds to have beneficial effect on the pathogenesis of hepatocellular carcinoma (HCC), this study was designed to investigative the apoptotic and anti-proliferative effects of these compounds on the human hepatoma Hep3B cell line. The Hep3B cells were treated with 17beta-estradiol (E2), diethylstilbestrol (DES), tamoxifen, and genistein. After treatments of these compounds at the concentration of 10(-6) or 10(-8) M, the Hep3B cells were demonstrated to have significant DNA fragmentation, nucleus condensation, cytochrome-c leaking from the mitochondria and caspase-3 activation by DAPI and Western blotting. The cells were also observed to have declined proliferative potential by MTT assay, arrested cell cycle by flow-cytometry measurements. However, the cytochrome-c leaking from the mitochondria induced by E2 and E2-like compounds was blocked totally by ICI 182,780 treatment. These finding suggest that estrogen and the estrogen-like compounds may induce anti-proliferative and apoptotic effects in Hep3B cells, and the E2 and the E2-like compounds mediated apoptotic effect was estrogen receptor dependent. Among the drugs tested, E2, E2 agonists (DES and genistein) and partial antagonist (tamoxifen), all showed the stronger anti-tumor potential.

Apoptosis↗
PubMed1987

Validity of the calculation of non-sex hormone-binding globulin-bound estradiol from total testosterone, total estradiol and sex hormone-binding globulin concentrations in human serum.

Recent evidences indicate that biologically available serum testosterone (T) and estradiol (E2) include not only the free fractions but also most of the albumin-bound fractions. These two serum T or E2 fractions constitute most of non-sex hormone-binding globulin (SHBG)-bound T or E2, respectively. It has been reported that the estimation of serum non-SHBG-bound T gives identical results when it is assayed experimentally or when it is calculated by a formula derived from the law of mass action assuming two binding systems (T-SHBG and T-albumin). In the present work, we have compared the results of the experimental measurement of non-SHBG-bound E2 with the calculated value derived by an equation based on the law of mass action considering four binding systems (E2-SHBG, T-SHBG, E2-albumin, T-albumin). It was found that the two estimations of non-SHBG-bound E2 correlated closely in normal men (r = 0.80), normal women (r = 0.90) and hirsute women (r = 0.98). When compared with a more complex calculation which includes 21 steroids and 3 binding proteins results also agreed closely. Values for the different T and E2 fractions in these groups of subjects are given. These calculations could be used, not only for clinical research, but also in clinical practice as an useful tool for evaluation of the sex hormone status of patients.

Estradiol↗
PubMed1976

Preparturient changes in plasma concentrations of estrone, estradiol-17beta and estradiol-17alpha in the fetal calf: effects of dexamethasone infusion.

The concentrations of total estrogens in fetal calf plasma were determined during a 6-10 day period immediately before delivery. Comparison was made between levels found in untreated calves and calves infused with dexamethasone at the rate of 0.1, 1.0 and 10 mg/24 hours. In untreated calves the plasma estrone, estradiol-17beta and estradio-17alpha levels remained relatively constant at 38 +/- 7 ng ml-1 (mean +/- SEM n = 3), 46 +/- 6 ng ml-1 and 29 +/- 5 ng ml-1 respectively. Infusion with dexamethasone at 0.1 mg/24 hr (3 calves) and 1.0 mg/24 hr (3 calves) was without dramatic effect on plasma estrogen levels. However, in one fetus infused with 10.0 mg/24 hr the dexamethasone treatment may have caused a transitory rise in the levels of all estrogens examined.

Animals↗
PubMed1993

Transformation of estrone, estradiol, and estrone sulfate in uterine and vaginal isolated cells of fetal guinea pig. Effect of various antiestrogens in the conversion of estrone sulfate to estradiol.

The metabolism of physiological concentrations (5 x 10(-9) M) of [3H]estrone (E1), [3H]estradiol (E2), and [3H]estrone sulfate (E1S) was studied in isolated fetal uterine and vaginal cells of guinea pigs in culture. After 24 hours of incubation in both cells, a large percentage (40-60%) of E1 is converted to E2; however, after incubation of E2, most of the radioactive material (45-65%) corresponds to unchanged E2. Similarly, in the incubation medium the concentration of E2 is significantly higher related to E1 after incubation with E1 or E2. An intense sulfotransferase activity is found for both estrogens, whereas in the culture medium the respective sulfates represent 27-45% of the total radioactive material after incubation with the uterine cells and 15-24% for the vaginal cells. Using E1S, significant hydrolysis is observed in both cells and the analysis of the freed radioactive material indicated a high percentage in E2 (66% in the uterine cells and 71% in the vaginal cells). The conversion of E1S to E2 was strongly decreased by the antiestrogens: tamoxifen, 4-hydroxy-tamoxifen, and ICI 164,384. The inhibitory effect in relation to the incubation with E1S only was 43-66% in the uterine cells and 50-85% in the vaginal cells. The present data suggest that estrogen sulfates can play an important biological role in the target tissues of the fetus, and that the enzymatic mechanisms of the bioavailability of E2 for the biological responses of the hormone can be operated in the target tissue itself.

Animals↗